Image forming apparatus, method of evaluating noise, and methods of manufacturing and modifying image forming apparatus
A method of manufacturing an image forming apparatus includes evaluating, based on a pair comparison method, sounds generated when forming an image, carrying out a multiple linear regression analysis using a difference between scores of the evaluation as a target variable and a difference between psycho-acoustic parameter values as an explanatory variable, deriving formula concerning the difference in scores of sound quality from a result of the analysis, substituting an average of the psycho-acoustic parameter values used to derive the formula into the formula, defining discomfort of the sound when all the parameter values are average values as zero, and deriving a sound quality evaluation formula, and designing each unit of the apparatus based on the sound quality evaluation formula.
1. An image forming apparatus that forms an image onto a recording medium, wherein
a discomfort index S calculated from an equation
S=A ×(loudness value)+ B ×(sharpness value)+ C ×(tonality value)+ D ×(impulsiveness value)+ E
where 0.213845≦A≦0.255694, 0.325852≦B≦0.443631, 2.049496≦C≦3.207187, 1.427895≦D≦1.708411, and −4.224266≦E≦−3.356324, using loudness, sharpness, tonality, and impulsiveness of a psycho-acoustic parameter obtained from a sound generated from the image forming apparatus when forming an image onto the recording medium satisfies an inequality
S≦0.5664Ln(ppm)-2.1364
where 14≦ppm≦38 Ln indicates natural log, and ppm is an output number of the recording medium per minute with A4 size in horizontal direction, wherein the sound is collected at a listening position approximately one meter from an edge of the image forming apparatus.
2. The image forming apparatus according to claim 1 , comprising:
a control unit that controls the image forming apparatus, wherein
the image forming apparatus has a plurality of operation modes,
the control unit selects one from the operation modes, and controls each unit of the image forming apparatus to form an image onto the recording medium, and
the index S satisfies the inequality in any one of the operation modes.
3. The image forming apparatus according to claim 1 , wherein
the listening position is based on the International Organization for Standardization 7779, and
the index S obtained from a sound collected from at least front direction of the image forming apparatus satisfies the inequality.
4. The image forming apparatus according to claim 1 , wherein
the listening position is based on the International Organization for Standardization 7779, and
an average of the index S's obtained from sounds collected from front, rear, left, and right directions of the apparatus satisfies the condition.
5. The image forming apparatus according to claim 1 , wherein
the listening position is based on the International Organization for Standardization 7779, and
the index S obtained from a sound collected from at least one direction among front, rear, left, and right directions of the image forming apparatus satisfies the inequality.
6. The image forming apparatus according to claim 1 , wherein
the listening position is based on the International Organization for Standardization 7779, and
the index S obtained from a sound collected from each of front, rear, left, and right directions of the image forming apparatus satisfies the inequality.
7. The image forming apparatus according to claim 1 , comprising:
a decreasing unit that decreases the sound generated from the image forming apparatus when forming an image onto the recording medium.
8. The image forming apparatus according to claim 7 , further comprising:
a stepping motor that drives predetermined parts of the image forming apparatus when forming an image onto the recording medium; and
a bracket member that holds the stepping motor, wherein
the decreasing unit includes an elastic material disposed between the stepping motor and the bracket member.
9. The image forming apparatus according to claim 7 , further comprising:
a stepping motor that drives predetermined parts of the image forming apparatus when forming an image onto the recording medium, wherein
the decreasing unit includes a drive control unit that drives the stepping motor in micro-step.
10. The image forming apparatus according to claim 7 , further comprising:
a motor that drives predetermined parts of the image forming apparatus when forming an image onto the recording medium, wherein
the decreasing unit includes a Helmholtz resonator that is disposed near the motor.
11. The image forming apparatus according to claim 7 , further comprising:
an image carrier of a cylindrical shape having a hollow portion; and
a charging unit that charges a surface of the image carrier, wherein
the decreasing unit is disposed in the hollow portion of the image carrier, and includes a damping material that suppresses vibration of the image carrier.
12. The image forming apparatus according to claim 1 , comprising:
a guide member including a flexible sheet that guides the recording medium along a predetermined feeding path, wherein an edge of the guide member is a bent portion of the flexible sheet, wherein the edge is in contact with the recording medium fed.
13. The image forming apparatus according to claim 1 , wherein a toner used to form an image onto the recording medium contains wax.
14. An image forming apparatus that forms an image onto a recording medium, wherein
a discomfort index S calculated from an equation
S=A ×(loudness value)+ B ×(sharpness value)+ C ×(tonality value)+ D ×(impulsiveness value)+ E
where A=0.2347697, B=0.3847411, C=2.6283418, D=1.5681529, and E=−3.790295483, using loudness, sharpness, tonality, and impulsiveness of a psycho-acoustic parameter obtained from a sound generated from the image forming apparatus when forming an image onto the recording medium satisfies an inequality
S≦ 0.5664Ln(ppm)−2.1364
where 14≦ppm≦38 Ln indicates natural log, and ppm is an output number of the recording medium per minute with A4 size in horizontal direction, wherein the sound is collected at a listening position approximately one meter from an edge of the image forming apparatus.
15. The image forming apparatus according to claim 14 , comprising:
a control unit that controls the image forming apparatus, wherein
the image forming apparatus has a plurality of operation modes,
the control unit selects one from the operation modes, and controls each unit of the image forming apparatus to form an image onto the recording medium, and
the index S satisfies the inequality in any one of the operation modes.
16. The image forming apparatus according to claim 14 , wherein the listening position is based on the International Organization for Standardization 7779, and
the index S obtained from a sound collected from at least front direction of the image forming apparatus satisfies the inequality.
17. The image forming apparatus according to claim 14 , wherein
the listening position is based on the International Organization for Standardization 7779, and
an average of the index S's obtained from sounds collected from front, rear, left, and right directions of the apparatus satisfies the condition.
18. The image forming apparatus according to claim 14 , wherein
the listening position is based on the International Organization for Standardization 7779, and
the index S obtained from a sound collected from at least one direction among front, rear, left, and right directions of the image forming apparatus satisfies the inequality.
19. The image forming apparatus according to claim 14 , wherein
the listening position is based on the International Organization for Standardization 7779, and
the index S obtained from a sound collected from each of front, rear, left, and right directions of the image forming apparatus satisfies the inequality.
20. The image forming apparatus according to claim 14 , comprising:
a decreasing unit that decreases the sound generated from the image forming apparatus when forming an image onto the recording medium.
21. The image forming apparatus according to claim 20 , further comprising:
a stepping motor that drives predetermined parts of the image forming apparatus when forming an image onto the recording medium; and
a bracket member that holds the stepping motor, wherein
the decreasing unit includes an elastic material disposed between the stepping motor and the bracket member.
22. The image forming apparatus according to claim 20 , further comprising:
a stepping motor that drives predetermined parts of the image forming apparatus when forming an image onto the recording medium, wherein
the decreasing unit includes a drive control unit that drives the stepping motor in micro-step.
23. The image forming apparatus according to claim 20 , further comprising:
a motor that drives predetermined parts of the image forming apparatus when forming an image onto the recording medium, wherein
the decreasing unit includes a Helmholtz resonator that is disposed near the motor.
24. The image forming apparatus according to claim 20 , further comprising:
an image carrier of a cylindrical shape having a hollow portion; and
a charging unit that charges a surface of the image carrier, wherein
the decreasing unit is disposed in the hollow portion of the image carrier, and includes a damping material that suppresses vibration of the image carrier.
25. The image forming apparatus according to claim 14 , comprising:
a guide member including a flexible sheet that guides the recording medium along a predetermined feeding path, wherein
an edge of the guide member is a bent portion of the flexible sheet, wherein the edge is in contact with the recording medium fed.
26. The image forming apparatus according to claim 14 , wherein a toner used to form an image onto the recording medium contains wax.
27. An image forming apparatus that forms an image onto a recording medium, wherein
a discomfort index S calculated from an equation
S=A ×(loudness value)+ B ×(sharpness value) C ×(tonality value) D ×(impulsiveness value) E
where 0.213845≦A≦0.255694, 0.325852≦B≦0.443631, 2.049496≦C≦3.207187, 1.427895≦D≦1.708411, and −4.224266≦E≦−3.356324, using loudness, sharpness, tonality, and impulsiveness of a psycho-acoustic parameter obtained from a sound generated from the image forming apparatus when forming an image onto the recording medium satisfies an inequality
S ≦0.532ln( v )−2.8381
where 62.5≦v≦185, ln indicates natural log, and v is a speed of forming an image onto the recording medium in millimeters per second, wherein the sound is collected at a listening position approximately one meter from an edge of the image forming apparatus.
28. The image forming apparatus according to claim 27 , comprising:
a control unit that controls the image forming apparatus, wherein
the image forming apparatus has a plurality of operation modes,
the control unit selects one from the operation modes, and controls each unit of the image forming apparatus to form an image onto the recording medium, and
the index S satisfies the inequality in any one of the operation modes.
29. The image forming apparatus according to claim 27 , wherein the listening position is based on the International Organization for Standardization 7779, and
the index S obtained from a sound collected from at least front direction of the image forming apparatus satisfies the inequality.
30. The image forming apparatus according to claim 27 , wherein the listening position is based on the International Organization for Standardization 7779, and
an average of the index S's obtained from sounds collected from front, rear, left, and right directions of the apparatus satisfies the condition.
31. The image forming apparatus according to claim 27 , wherein
the listening position is based on the International Organization for Standardization 7779, and
the index S obtained from a sound collected from at least one direction among front, rear, left, and right directions of the image forming apparatus satisfies the inequality.
32. The image forming apparatus according to claim 27 , wherein the listening position is based on the International Organization for Standardization 7779, and
the index S obtained from a sound collected from each of front, rear, left, and right directions of the image forming apparatus satisfies the inequality.
33. The image forming apparatus according to claim 27 , comprising:
a decreasing unit that decreases the sound generated from the image forming apparatus when forming an image onto the recording medium.
34. The image forming apparatus according to claim 33 , further comprising:
a stepping motor that drives predetermined parts of the image forming apparatus when forming an image onto the recording medium; and
a bracket member that holds the stepping motor, wherein
the decreasing unit includes an elastic material disposed between the stepping motor and the bracket member.
35. The image forming apparatus according to claim 33 , further comprising:
a stepping motor that drives predetermined parts of the image forming apparatus when forming an image onto the recording medium, wherein the decreasing unit includes a drive control unit that drives the stepping motor in micro-step.
36. The image forming apparatus according to claim 33 , further comprising:
a motor that drives predetermined parts of the image forming apparatus when forming an image onto the recording medium, wherein
the decreasing unit includes a Helmholtz resonator that is disposed near the motor.
37. The image forming apparatus according to claim 33 , further comprising:
an image carrier of a cylindrical shape having a hollow portion; and
a charging unit that charges a surface of the image carrier, wherein
the decreasing unit is disposed in the hollow portion of the image carrier, and includes a damping material that suppresses vibration of the image carrier.
38. The image forming apparatus according to claim 27 , comprising:
a guide member including a flexible sheet that guides the recording medium along a predetermined feeding path, wherein
an edge of the guide member is a bent portion of the flexible sheet, wherein the edge is in contact with the recording medium fed.
39. The image forming apparatus according to claim 27 , wherein a toner used to form an image onto the recording medium contains wax.
40. An image forming apparatus that forms an image onto a recording medium, wherein p 1 a discomfort index S calculated from an equation
S=A ×(loudness value)+ B ×(sharpness value)+ C ×(tonality value)+ D ×(impulsiveness value)+ E
where A=0.2347697, B=0.3847411, C=2.6283418, D1.5681529, and E=−3.790295483, using loudness, sharpness, tonality, and impulsiveness of a psycho-acoustic parameter obtained from a sound generated from the image forming apparatus when forming an image onto the recording medium satisfies an inequality
S ≦0.532ln( v )−2.8381
where 62.5≦v≦185, ln indicates natural log, and v is a speed of forming an image onto the recording medium in millimeters per second, wherein the sound is collected at a listening position approximately one meter from an edge of the image forming apparatus.
41. The image forming apparatus according to any one of claims 1 to 4 , comprising:
a control unit that controls the image forming apparatus, wherein
the image forming apparatus has a plurality of operation modes,
the control unit selects one from the operation modes, and controls each unit of the image forming apparatus to form an image onto the recording medium, and
the index S satisfies the inequality in any one of the operation modes.
42. The image forming apparatus according to any one of claims 1 to 4 , wherein
the listening position is based on the International Organization for Standardization 7779, and
the index S obtained from a sound collected from at least front direction of the image forming apparatus satisfies the inequality.
43. The image forming apparatus according to any one of claims 1 to 4 , wherein the listening position is based on the International Organization for Standardization 7779, and
an average of the index S's obtained from sounds collected from front, rear, left, and right directions of the apparatus satisfies the condition.
44. The image forming apparatus according to any one of claims 1 to 4 , wherein
the listening position is based on the International Organization for Standardization 7779, and
the index S obtained from a sound collected from at least one direction among front, rear, left, and right directions of the image forming apparatus satisfies the inequality.
45. The image forming apparatus according to any one of claims 1 to 4 , wherein
the listening position is based on the International Organization for Standardization 7779, and
the index S obtained from a sound collected from each of front, rear, left, and right directions of the image forming apparatus satisfies the inequality.
46. The image forming apparatus according to any one of claims 1 to 4 , comprising:
a decreasing unit that decreases the sound generated from the image forming apparatus when forming an image onto the recording medium.
47. The image forming apparatus according to claim 10 , further comprising:
a stepping motor that drives predetermined parts of the image forming apparatus when forming an image onto the recording medium; and
a bracket member that holds the stepping motor, wherein
the decreasing unit includes an elastic material disposed between the stepping motor and the bracket member.
48. The image forming apparatus according to claim 10 , further comprising:
a stepping motor that drives predetermined parts of the image forming apparatus when forming an image onto the recording medium, wherein the decreasing unit includes a drive control unit that drives the stepping motor in micro-step.
49. The image forming apparatus according to claim 10 , further comprising:
a motor that drives predetermined parts of the image forming apparatus when forming an image onto the recording medium, wherein
the decreasing unit includes a Helmholtz resonator that is disposed near the motor.
50. The image forming apparatus according to claim 10 , further comprising:
an image carrier of a cylindrical shape having a hollow portion; and
a charging unit that charges a surface of the image carrier, wherein
the decreasing unit is disposed in the hollow portion of the image carrier, and includes a damping material that suppresses vibration of the image carrier.
51. The image forming apparatus according to any one of claims 1 to 4 , comprising:
a guide member including a flexible sheet that guides the recording medium along a predetermined feeding path, wherein
an edge of the guide member is a bent portion of the flexible sheet, wherein the edge is in contact with the recording medium fed.
52. The image forming apparatus according to any one of claims 1 to 4 , wherein a toner used to form an image onto the recording medium contains wax.
53. A method of manufacturing an image forming apparatus that forms an image onto a recording medium, the method comprising:
designing the image forming apparatus so that a discomfort index S calculated from an equation
S=A ×(loudness value)+ B ×(sharpness value)+ C ×(tonality value)+ D ×(impulsiveness value)+ E
where 0.213845≦A≦0.255694, 0.325852≦B≦0.443631, 2.049496≦C≦3.207187, 1.427895≦D≦1.708411, and −4.224266≦E≦−3.356324, using loudness, sharpness, tonality, and impulsiveness of a psycho-acoustic parameter obtained from a sound generated from the image forming apparatus when forming an image onto the recording medium satisfies an inequality
S ≦0.5664Ln(ppm)−2.1364
where 14≦ppm≦38, Ln indicates natural log, and ppm is an output number of the recording medium per minute with A4 size in horizontal direction, wherein the sound is collected at a listening position approximately one meter from an edge of the image forming apparatus to be fabricated; and
manufacturing the image forming apparatus based on a result of the designing.
54. A method of manufacturing an image forming apparatus that forms an image onto a recording medium, the method comprising:
designing the image forming apparatus so that an a discomfort index S calculated from an equation
S=A ×(loudness value)+ B ×(sharpness value)+ C ×(tonality value)+ D ×(impulsiveness value)+ E
where A=0.2347697, B=0.3847411, C=2.6283418, D=1.5681529, and E=−3.790295483, using loudness, sharpness, tonality, and impulsiveness of a psycho-acoustic parameter obtained from a sound generated from the image forming apparatus when forming an image onto the recording medium satisfies an inequality
S ≦0.5664Ln(ppm)−2. 1364
where 14≦ppm≦38, Ln indicates natural log, and ppm is an output number of the recording medium per minute with A4 size in horizontal direction, wherein the sound is collected at a listening position approximately one meter from an edge of the image forming apparatus to be fabricated; and
manufacturing the image forming apparatus based on a result of the designing.
55. A method of manufacturing an image forming apparatus that forms an image onto a recording medium, the method comprising:
designing the image forming apparatus so that a discomfort index S calculated from an equation
S=A ×(loudness value)+ B ×(sharpness value)+ C ×(tonality value)+ D ×(impulsiveness value)+ E
where 0.213845≦A≦0.255694, 0.325852≦B≦0.443631, 2.049496≦C≦3.207187, 1.427895≦D≦1.708411, and −4.224266≦E≦−3.356324, using loudness, sharpness, tonality, and impulsiveness of a psycho-acoustic parameter obtained from a sound generated from the image forming apparatus when forming an image onto the recording medium satisfies an inequality
S ≦0.532ln( v )−2.8381
where 62.5≦v≦185, ln indicates natural log, and v is a speed of forming an image onto the recording medium in millimeters per second, wherein the sound is collected at a listening position approximately one meter from an edge of the image forming apparatus to be fabricated; and
fabricating the image forming apparatus based on a result of the designing.
56. A method of manufacturing an image forming apparatus that forms an image onto a recording medium, the method comprising:
designing the image forming apparatus so that a discomfort index S calculated from an equation
S=A ×(loudness value)+ B ×(sharpness value)+ C ×(tonality value)+ D ×(impulsiveness value)+ E
where A=0.2347697, B=0.3847411, C=2.6283418, D=1.5681529, and E=−3.790295483, using loudness, sharpness, tonality, and impulsiveness of a psycho-acoustic parameter obtained from a sound generated from the image forming apparatus when forming an image onto the recording medium satisfies an inequality
S ≦0.532ln( v )−2.8381
where 62.5≦v≦185, ln indicates natural log, and v is a speed of forming an image onto the recording medium in millimeters per second, wherein the sound is collected at a listening position approximately one meter from an edge of the image forming apparatus to be fabricated; and
manufacturing the image forming apparatus based on a result of the designing.
57. A method of modifying an image forming apparatus that forms an image onto a recording medium, the method comprising:
modifying the image forming apparatus so that a discomfort index S calculated from an equation
S=A ×(loudness value)+ B ×(sharpness value)+ C ×(tonality value)+ D ×(impulsiveness value)+ E
where 0.213845≦A≦0.255694, 0.325852≦B≦0.443631, 2.049496≦C≦3.207187, 1.427895≦D≦1.708411, and −4.224266≦E≦−3.356324, using loudness, sharpness, tonality, and impulsiveness of a psycho-acoustic parameter obtained from a sound generated from the image forming apparatus when forming an image onto the recording medium satisfies an inequality
S 0.5664Ln(ppm)−2.1364
where 14≦ppm≦38, Ln indicates natural log, and ppm is an output number of the recording medium per minute with A4 size in horizontal direction, wherein the sound is collected at a listening position approximately one meter from an edge of the image forming apparatus to be modified.
58. A method of modifying an image forming apparatus that fonns an image onto a recording medium, the method comprising:
modifying the image forming apparatus so that a discomfort index S calculated from an equation
S=A ×(loudness value)+ B ×(sharpness value)+ C ×(tonality value)+ D ×(impulsiveness value)+ E
where A=0.2347697, B=0.3847411, C=2.6283418, D=1.5681529, and E=−3.790295483, using loudness, sharpness, tonality, and impulsiveness of a psycho-acoustic parameter obtained from a sound generated from the image forming apparatus when forming an image onto the recording medium satisfies an inequality
S 0.5664Ln(ppm)−2.1364
where 14≦ppm≦38, Ln indicates natural log, and ppm is an output number of the recording medium per minute with A4 size in horizontal direction, wherein the sound is collected at a listening position approximately one meter from an edge of the image forming apparatus to be modified.
59. A method of modifying an image forming apparatus that forms an image onto a recording medium, the method comprising:
modifying the image forming apparatus so that an a discomfort index S calculated from an equation
S=A ×(loudness value)+ B ×(sharpness value)+ C ×(tonality value)+ D ×(impulsiveness value)+ E
where 0.213845≦A≦0.255694, 0.325852≦B≦0.443631, 2.049496≦C≦3.207187, 1.427895≦D≦1.708411, and −4.224266≦E≦−3.356324, using loudness, sharpness, tonality, and impulsiveness of a psycho-acoustic parameter obtained from a sound generated from the image forming apparatus when forming an image onto the recording medium satisfies an inequality
S 0.532ln( v )−2.8381
where 62.5v185, In indicates natural log, and v is a speed of forming an image onto the recording medium in millimeters per second, wherein the sound is collected at a listening position approximately one meter from an edge of the image forming apparatus to be modified.
60. A method of modifying an image forming apparatus that forms an image onto a recording medium, the method comprising:
modifying the image forming apparatus so that a discomfort index S calculated from an equation
S=A (loudness value)+ B ×(sharpness value)+ C ×(tonality value)+ D ×(impulsiveness value)+ E
where A=0.2347697, B=0.3847411, C2.6283418, D=1.5681529, and E=−3.790295483, using loudness, sharpness, tonality, and impulsiveness of a psycho-acoustic parameter obtained from a sound generated from the image forming apparatus when forming an image onto the recording medium satisfies an inequality
S ≦0.532ln( v )−2.8381
where 62.5≦v≦185, In indicates natural log, and v is a speed of forming an image onto the recording medium in millimeters per second, wherein the sound is collected at a listening position approximately one meter from an edge of the image forming apparatus to be modified.
61. A method of evaluating sound generated from an image forming apparatus when forming an image onto a recording medium, the method comprising:
evaluating a plurality of kinds of the sound based on a pair comparison method;
performing a multiple linear regression analysis using a difference between scores of the evaluation as a target variable and a difference between psycho-acoustic parameter values as an explanatory variable;
deriving an equation concerning the difference between scores of sound quality from a result of the analysis, as follows
α
i
-
α
j
=
∑
l
=
1
L
b
l
(
x
l
i
-
x
l
j
)
where αn is subjective value with respect to discomfort of the sound where n=1,2, . . . i, . . . j, . . .,n, b i is a regression coefficient, x 1i and x 1j are Psycho-acoustic parameter values of two sounds to be compared where i=1,2,3 . . ., n and l=1,2,3 . . ., L;
substituting an average of the psycho-acoustic parameter values used to derive the equation, into the equation;
defining the discomfort of the sound when all the parameter values are average values as zero;
deriving a sound quality evaluation equation to estimate a score of the discomfort of the sound; and
evaluating the sound quality using the sound quality evaluation equation derived.
62. A method of manufacturing an image forming apparatus that forms an image onto a recording medium, the method comprising:
evaluating a plurality of kinds of the sound based on a pair comparison method;
performing a multiple linear regression analysis using a difference between scores of the evaluation as a target variable and a difference between psycho-acoustic parameter values as an explanatory variable;
deriving an equation concerning the difference between scores of sound quality from a result of the analysis, as follows
α
i
-
α
j
=
∑
l
=
1
L
b
i
(
x
li
-
x
lj
)
where αn is subjective value with respect to discomfort of the sound where n=1,2, . . . i, . . . j, . . ., n, b i is a regression coefficient, x 1i and x 1j are Psycho-acoustic parameter values of two sounds to be compared where i=1,2,3 . . ., n and 1=1,2,3 . . ., L;
substituting an average of the psycho-acoustic parameter values used to derive the equation, into the equation;
defining the discomfort of the sound when all the parameter values are average values as zero;
deriving a sound quality evaluation equation to estimate a score of the discomfort of the sound;
evaluating the sound quality using the sound quality evaluation equation derived;
designing each unit of the image forming apparatus so that a result of the evaluating satisfies a predetermined condition; and
manufacturing the image forming apparatus based on a result of the designing.
63. A method of modifying an image forming apparatus that forms an image onto a recording medium, the method comprising:
evaluating a plurality of kinds of the sound based on a pair comparison method;
performing a multiple linear regression analysis using a difference between scores of the evaluation as a target variable and a difference between psycho-acoustic parameter values as an explanatory variable;
deriving an equation concerning the difference between scores of sound quality from a result of the analysis, as follows
α
i
-
α
j
=
∑
l
=
1
L
b
i
(
x
li
-
x
lj
)
where αn is subjective value with respect to discomfort of the sound where n1,2, . . . i, . . . j, . . ., n, b i is a regression coefficient, x 1i , and x 1j are Psycho-acoustic parameter values of two sounds to be compared where i=1,2,3 . . ., n and 1=1,2,3 . . ., L;
substituting an average of the psycho-acoustic parameter values used to derive the equation, into the equation;
defining the discomfort of the sound when all the parameter values are average values as zero;
deriving a sound quality evaluation equation to estimate a score of the discomfort of the sound;
evaluating the sound quality of sound generated from the image forming apparatus to be modified using the sound quality evaluation equation derived; and
modifying corresponding units of the image forming apparatus to be modified based on a result of the evaluating.
64. An image forming apparatus that forms an image onto a recording medium, wherein
a discomfort probability P calculated from an equation
P =1/(1+exp(− z ))
where z=A×(loudness value)+B×(sharpness value)+C×(tonality value)+D×(impulsiveness value)+E
where 0.76545285≦A≦0.84940259, 1.27685159≦B≦1.48461447, 8.11323413≦C≦9.98398583, 5.30484579≦D≦5.87837423, −14.10339529≦E≦−12.47284396, using loudness, sharpness, tonality, and impulsiveness of a psycho-acoustic parameter obtained from a sound generated from the image forming apparatus when forming an image onto the recording medium satisfies an inequality
P 0.3383Ln(ppm)−0.8103
where 14≦ppm≦38 and ppm is an output number of the recording medium per minute with A4 size in horizontal direction, wherein the sound is collected at a listening position approximately one meter from an edge of the image forming apparatus.
65. The image forming apparatus according to claim 64 , comprising:
a control unit that controls the image forming apparatus, wherein
the image forming apparatus has a plurality of operation modes,
the control unit selects one from the operation modes, and controls each unit of the image forming apparatus to form an image onto the recording medium, and
the probability P satisfies the inequality in any one of the operation modes.
66. The image forming apparatus according to claim 64 , wherein
the listening position is based on the International Organization for Standardization 7779, and
the probability P obtained from a sound collected from at least front direction of the image forming apparatus satisfies the inequality.
67. The image forming apparatus according to claim 64 , wherein
the listening position is based on the International Organization for Standardization 7779, and
an average of the probability P's obtained from sounds collected from front, rear, left, and right directions of the apparatus satisfies the condition.
68. The image forming apparatus according to claim 64 , wherein
the listening position is based on the International Organization for Standardization 7779, and
the probability P obtained from a sound collected from at least one direction among front, rear, left, and right directions of the image forming apparatus satisfies the inequality.
69. The image forming apparatus according to claim 64 , wherein
the listening position is based on the International Organization for Standardization 7779, and
the probability P obtained from a sound collected from each of front, rear, left, and right directions of the image forming apparatus satisfies the inequality.
70. The image forming apparatus according to claim 64 ,
comprising:
a decreasing unit that decreases the sound generated from the image forming apparatus when forming an image onto the recording medium.
71. The image forming apparatus according to claim 70 , further comprising:
a stepping motor that drives predetermined parts of the image forming apparatus when forming an image onto the recording medium; and
a bracket member that holds the stepping motor, wherein
the decreasing unit includes an elastic material disposed between the stepping motor and the bracket member.
72. The image forming apparatus according to claim 70 , further comprising:
a stepping motor that drives predetermined parts of the image forming apparatus when forming an image onto the recording medium, wherein
the decreasing unit includes a drive control unit that drives the stepping motor in micro-step.
73. The image forming apparatus according to claim 70 , further comprising:
a motor that drives predetermined parts of the image forming apparatus when forming an image onto the recording medium, wherein
the decreasing unit includes a Helmholtz resonator that is disposed near the motor.
74. The image forming apparatus according to claim 70 , further comprising:
an image carrier of a cylindrical shape having a hollow portion; and
a charging unit that charges a surface of the image carrier, wherein
the decreasing unit is disposed in the hollow portion of the image carrier, and includes a damping material that suppresses vibration of the image carrier.
75. The image forming apparatus according to claim 64 , comprising:
a guide member including a flexible sheet that guides the recording medium along a predetermined feeding path, wherein
an edge of the guide member is a bent portion of the flexible sheet, wherein the edge is in contact with the recording medium fed.
76. The image forming apparatus according to claim 70 , wherein a toner used to form an image onto the recording medium contains wax.
77. An image forming apparatus that forms an image onto a recording medium, wherein
a discomfort probability P calculated from an equation
P 1/(1+exp(− z 35 2σ))
where z=A ×(loudness value)+ B ×(sharpness value)+ C ×(tonality value)+ D ×(impulsiveness value)+ E
where A=0.80742768, B=1.38073296, C=9.04860954, D5.59160971, and E−13.28811895, and a standard deviation σ is 0.721307, using loudness, sharpness, tonality, and impulsiveness of a psycho-acoustic parameter obtained from a sound generated from the image forming apparatus when forming an image onto the recording medium satisfies an inequality
P ≦0.3383Ln(ppm)−0.8103
where 14≦ppm≦38, and ppm is an output number of the recording medium per minute with A4 size in horizontal direction, wherein the sound is collected at a listening position approximately one meter from an edge of the image forming apparatus.
78. The image forming apparatus according to claim 77 , comprising:
a control unit that controls the image forming apparatus, wherein
the image forming apparatus has a plurality of operation modes,
the control unit selects one from the operation modes, and controls each unit of the image forming apparatus to form an image onto the recording medium, and
the probability P satisfies the inequality in any one of the operation modes.
79. The image forming apparatus according to claim 77 , wherein
the listening position is based on the International Organization for Standardization 7779, and
the probability P obtained from a sound collected from at least front direction of the image forming apparatus satisfies the inequality.
80. The image forming apparatus according to claim 77 , wherein
the listening position is based on the International Organization for Standardization 7779, and
an average of the probability P's obtained from sounds collected from front, rear, left, and right directions of the apparatus satisfies the condition.
81. The image forming apparatus according to claim 77 , wherein
the listening position is based on the International Organization for Standardization 7779, and
the probability P obtained from a sound collected from at least one direction among front, rear, left, and right directions of the image forming apparatus satisfies the inequality.
82. The image forming apparatus according to claim 77 , wherein
the listening position is based on the International Organization for Standardization 7779, and
the probability P obtained from a sound collected from each of front, rear, left, and right directions of the image forming apparatus satisfies the inequality.
83. The image forming apparatus according to claim 77 , comprising:
a decreasing unit that decreases the sound generated from the image forming apparatus when forming an image onto the recording medium.
84. The image forming apparatus according to claim 83 , further comprising:
a stepping motor that drives predetermined parts of the image forming apparatus when forming an image onto the recording medium; and
a bracket member that holds the stepping motor, wherein
the decreasing unit includes an elastic material disposed between the stepping motor and the bracket member.
85. The image forming apparatus according to claim 83 , further comprising:
a stepping motor that drives predetermined parts of the image forming apparatus when forming an image onto the recording medium, wherein
the decreasing unit includes a drive control unit that drives the stepping motor in micro-step.
86. The image forming apparatus according to claim 83 , further comprising:
a motor that drives predetermined parts of the image forming apparatus when forming an image onto the recording medium, wherein
the decreasing unit includes a Helmholtz resonator that is disposed near the motor.
87. The image forming apparatus according to claim 83 , further comprising:
an image carrier of a cylindrical shape having a hollow portion; and
a charging unit that charges a surface of the image carrier, wherein
the decreasing unit is disposed in the hollow portion of the image carrier, and includes a damping material that suppresses vibration of the image carrier.
88. The image forming apparatus according to claim 77 , comprising:
a guide member including a flexible sheet that guides the recording medium along a predetermined feeding path, wherein
an edge of the guide member is a bent portion of the flexible sheet, wherein the edge is in contact with the recording medium fed.
89. The image forming apparatus according to claim 83 , wherein a toner used to form an image onto the recording medium contains wax.
90. An image forming apparatus that forms an image onto a recording medium, wherein
a discomfort probability P calculated from an equation
P =1/(1+exp(− z ))
where z=A ×(loudness value)+ B ×(sharpness value)+ C ×(tonality value)+ D ×(impulsiveness value)+ E
where A=0.80742768, B=1.38073296, C=9.04860954, D=5.59160971, and E=−13.28811895, using loudness, sharpness, tonality, and impulsiveness of a psycho-acoustic parameter obtained from a sound generated from the image forming apparatus when forming an image onto the recording medium satisfies an inequality
P ≦0.3383Ln(ppm)−0.8103
where 14≦ppm≦38, and ppm is an output number of the recording medium per minute with A4 size in horizontal direction, wherein the sound is collected at a listening position approximately one meter from an edge of the image forming apparatus.
91. The image forming apparatus according to claim 90 , comprising:
a control unit that controls the image forming apparatus, wherein
the image forming apparatus has a plurality of operation modes,
the control unit selects one from the operation modes, and controls each unit of the image forming apparatus to form an image onto the recording medium, and
the probability P satisfies the inequality in any one of the operation modes.
92. The image forming apparatus according to claim 90 , wherein
the listening position is based on the International Organization for Standardization 7779, and
the probability P obtained from a sound collected from at least front direction of the image forming apparatus satisfies the inequality.
93. The image forming apparatus according to claim 90 , wherein
the listening position is based on the International Organization for Standardization 7779, and
an average of the probability P's obtained from sounds collected from front, rear, left, and right directions of the apparatus satisfies the condition.
94. The image forming apparatus according to claim 90 , wherein
the listening position is based on the International Organization for Standardization 7779, and
the probability P obtained from a sound collected from at least one direction among front, rear, left, and right directions of the image forming apparatus satisfies the inequality.
95. The image forming apparatus according to claim 90 , wherein
the listening position is based on the International Organization for Standardization 7779, and
the probability P obtained from a sound collected from each of front, rear, left, and right directions of the image forming apparatus satisfies the inequality.
96. The image forming apparatus according to claim 90 , comprising:
a decreasing unit that decreases the sound generated from the image forming apparatus when forming an image onto the recording medium.
97. The image forming apparatus according to claim 96 , further comprising:
a stepping motor that drives predetermined parts of the image forming apparatus when forming an image onto the recording medium; and
a bracket member that holds the stepping motor, wherein
the decreasing unit includes an elastic material disposed between the stepping motor and the bracket member.
98. The image forming apparatus according to claim 96 , further comprising:
a stepping motor that drives predetermined parts of the image forming apparatus when forming an image onto the recording medium, wherein
the decreasing unit includes a drive control unit that drives the stepping motor in micro-step.
99. The image forming apparatus according to claim 96 , further comprising:
a motor that drives predetermined parts of the image forming apparatus when forming an image onto the recording medium, wherein
the decreasing unit includes a Helmholtz resonator that is disposed near the motor.
100. The image forming apparatus according to claim 96 , further comprising:
an image carrier of a cylindrical shape having a hollow portion; and
a charging unit that charges a surface of the image carrier, wherein
the decreasing unit is disposed in the hollow portion of the image carrier, and includes a damping material that suppresses vibration of the image carrier.
101. The image forming apparatus according to claim 90 , comprising:
a guide member including a flexible sheet that guides the recording medium along a predetermined feeding path, wherein
an edge of the guide member is a bent portion of the flexible sheet, wherein the edge is in contact with the recording medium fed.
102. The image forming apparatus according to claim 96 , wherein
a toner used to form an image onto the recording medium contains wax.
103. An image forming apparatus that forms an image onto a recording medium, wherein
a discomfort probability P calculated from an equation
P =1/(1+exp(− z ))
where z=A ×(loudness value)+ B ×(sharpness value)+ C ×(tonality value)+ D ×(impulsiveness value)+ E
where 0.76545285≦A≦0.84940259, 1.27685159≦B≦1.48461447, 8.11323413≦C≦9.98398583, 5.30484579≦D≦5.87837423, −14.10339529≦E≦−12.47284396, using loudness, sharpness, tonality, and impulsiveness of a psycho-acoustic parameter obtained from a sound generated from the image forming apparatus when forming an image onto the recording medium satisfies an inequality
P ≦0.3201Ln( v )−1/2402
where 62.5≦v≦185, and v is a speed of forming an image onto the recording medium in millimeters per second, wherein the sound is collected at a listening position approximately one meter from an edge of the image forming apparatus.
104. The image forming apparatus according to claim 103 , comprising:
a control unit that controls the image forming apparatus, wherein
the image forming apparatus has a plurality of operation modes,
the control unit selects one from the operation modes, and controls each unit of the image forming apparatus to form an image onto the recording medium, and
the probability P satisfies the inequality in any one of the operation modes.
105. The image forming apparatus according to claim 103 , wherein
the listening position is based on the International Organization for Standardization 7779, and
the probability P obtained from a sound collected from at least front direction of the image forming apparatus satisfies the inequality.
106. The image forming apparatus according to claim 103 , wherein
the listening position is based on the International Organization for Standardization 7779, and
an average of the probability P's obtained from sounds collected from front, rear, left, and right directions of the apparatus satisfies the condition.
107. The image forming apparatus according to claim 103 , wherein
the listening position is based on the International Organization for Standardization 7779, and
the probability P obtained from a sound collected from at least one direction among front, rear, left, and right directions of the image forming apparatus satisfies the inequality.
108. The image forming apparatus according to claim 103 , wherein
the listening position is based on the International Organization for Standardization 7779, and
the probability P obtained from a sound collected from each of front, rear, left, and
right directions of the image forming apparatus satisfies the inequality.
109. The image forming apparatus according to claim 103 , comprising:
a decreasing unit that decreases the sound generated from the image forming apparatus when forming an image onto the recording medium.
110. The image forming apparatus according to claim 109 , further comprising:
a stepping motor that drives predetermined parts of the image forming apparatus when forming an image onto the recording medium; and
a bracket member that holds the stepping motor, wherein
the decreasing unit includes an elastic material disposed between the stepping motor and the bracket member.
111. The image forming apparatus according to claim 109 , further comprising:
a stepping motor that drives predetermined parts of the image forming apparatus when forming an image onto the recording medium, wherein
the decreasing unit includes a drive control unit that drives the stepping motor in micro-step.
112. The image forming apparatus according to claim 109 , further comprising:
a motor that drives predetermined parts of the image forming apparatus when forming an image onto the recording medium, wherein
the decreasing unit includes a Helmholtz resonator that is disposed near the motor.
113. The image forming apparatus according to claim 109 , further comprising:
a image carrier of a cylindrical shape having a hollow portion; and
a charging unit that charges a surface of the image carrier, wherein
the decreasing unit is disposed in the hollow portion of the image carrier, and includes a damping material that suppresses vibration of the image carrier.
114. The image forming apparatus according to claim 103 , comprising:
a guide member including a flexible sheet that guides the recording medium along a predetermined feeding path, wherein
an edge of the guide member is a bent portion of the flexible sheet, wherein the edge is in contact with the recording medium fed.
115. The image forming apparatus according to claim 109 , wherein
a toner used to form an image onto the recording medium contains wax.
116. An image forming apparatus that forms an image onto a recording medium, wherein
a discomfort probability P calculated from an equation
P =1/(1+exp(− z ±2σ))
where z=A ×(loudness value)+ B ×(sharpness value)+ C ×(tonality value)+ D ×(impulsiveness value)+ E
where A=0.80742768, B=1.38073296, C=9.04860954, D=5.59160971, and E=−13.28811895, and a standard deviation σ is 0.721307, using loudness, sharpness, tonality,
and impulsiveness of a psycho-acoustic parameter obtained from a sound generated from the image forming apparatus when forming an image onto the recording medium satisfies an inequality
P ≦0.3202Ln( v )−1.2402
where 62.5≦v≦185, and v is a speed of forming an image onto the recording medium in millimeters per second, wherein the sound is collected at a listening position approximately one meter from an edge of the image forming apparatus.
117. The image forming apparatus according to claim 116 , comprising:
a control unit that controls the image forming apparatus, wherein
the image forming apparatus has a plurality of operation modes,
the control unit selects one from the operation modes, and controls each unit of the image forming apparatus to form an image onto the recording medium, and
the probability P satisfies the inequality in any one of the operation modes.
118. The image forming apparatus according to claim 116 , wherein
the listening position is based on the International Organization for Standardization 7779, and
the probability P obtained from a sound collected from at least front direction of the image forming apparatus satisfies the inequality.
119. The image forming apparatus according to claim 116 , wherein
the listening position is based on the International Organization for Standardization 7779, and
an average of the probability P's obtained from sounds collected from front, rear, left, and right directions of the apparatus satisfies the condition.
120. The image forming apparatus according to claim 116 , wherein
the listening position is based on the International Organization for Standardization 7779, and
the probability P obtained from a sound collected from at least one direction among front, rear, left, and right directions of the image forming apparatus satisfies the inequality.
121. The image forming apparatus according to claim 116 , wherein
the listening position is based on the International Organization for Standardization 7779, and
the probability P obtained from a sound collected from each of front, rear, left, and
right directions of the image forming apparatus satisfies the inequality.
122. The image forming apparatus according to claim 116 , comprising:
a decreasing unit that decreases the sound generated from the image forming apparatus when forming an image onto the recording medium.
123. The image forming apparatus according to claim 122 , further comprising:
a stepping motor that drives predetermined parts of the image forming apparatus when forming an image onto the recording medium; and
a bracket member that holds the stepping motor, wherein
the decreasing unit includes an elastic material disposed between the stepping motor and the bracket member.
124. The image forming apparatus according to claim 122 , further comprising:
a stepping motor that drives predetermined parts of the image forming apparatus when forming an image onto the recording medium, wherein
the decreasing unit includes a drive control unit that drives the stepping motor in micro-step.
125. The image forming apparatus according to claim 122 , further comprising:
a motor that drives predetermined parts of the image forming apparatus when forming an image onto the recording medium, wherein
the decreasing unit includes a Helmholtz resonator that is disposed near the motor.
126. The image forming apparatus according to claim 122 , further comprising:
an image carrier of a cylindrical shape having a hollow portion; and
a charging unit that charges a surface of the image carrier, wherein
the decreasing unit is disposed in the hollow portion of the image carrier, and includes a damping material that suppresses vibration of the image carrier.
127. The image forming apparatus according to claim 116 , comprising:
a guide member including a flexible sheet that guides the recording medium along a predetermined feeding path, wherein
an edge of the guide member is a bent portion of the flexible sheet, wherein the edge is in contact with the recording medium fed.
128. The image forming apparatus according to claim 122 , wherein a toner used to form an image onto the recording medium contains wax.
129. An image forming apparatus that forms an image onto a recording medium, wherein
a discomfort probability P calculated from an equation
P =1/(1+exp(− z ))
where z=A ×(loudness value)+ B ×(sharpness value)+ C ×(tonality value)+ D ×(impulsiveness value)+ E
where A=0.80742768, B=1.38073296, C=9.04860954, D=5.59160971, and E=−13.28811895, using loudness, sharpness, tonality, and impulsiveness of a psycho-acoustic parameter obtained from a sound generated from the image forming apparatus when forming an image onto the recording medium satisfies an inequality
P ≦0.3201Ln( v )−1.2402,
where 62.5≦v≦185, and v is a speed of forming an image onto the recording medium in millimeters per second, wherein the sound is
collected at a listening position approximately one meter from an edge of the image forming apparatus.
130. The image forming apparatus according to claim 129 , comprising:
a control unit that controls the image forming apparatus, wherein
the image forming apparatus has a plurality of operation modes,
the control unit selects one from the operation modes, and controls each unit of the image forming apparatus to form an image onto the recording medium, and
the probability P satisfies the inequality in any one of the operation modes.
131. The image forming apparatus according to claim 129 , wherein
the listening position is based on the International Organization for Standardization 7779, and
the probability P obtained from a sound collected from at least front direction of the image forming apparatus satisfies the inequality.
132. The image forming apparatus according to claim 129 , wherein
the listening position is based on the International Organization for Standardization 7779, and
an average of the probability P's obtained from sounds collected from front, rear, left, and right directions of the apparatus satisfies the condition.
133. The image forming apparatus according to claim 129 , wherein
the listening position is based on the International Organization for Standardization 7779, and
the probability P obtained from a sound collected from at least one direction among front, rear, left, and right directions of the image forming apparatus satisfies the inequality.
134. The image forming apparatus according to claim 129 , wherein
the listening position is based on the International Organization for Standardization 7779, and
the probability P obtained from a sound collected from each of front, rear, left, and right directions of the image forming apparatus satisfies the inequality.
135. The image forming apparatus according to claim 129 , comprising:
a decreasing unit that decreases the sound generated from the image forming apparatus when forming an image onto the recording medium.
136. The image forming apparatus according to claim 135 , further comprising:
a stepping motor that drives predetermined parts of the image forming apparatus when forming an image onto the recording medium; and
a bracket member that holds the stepping motor, wherein
the decreasing unit includes an elastic material disposed between the stepping motor and the bracket member.
137. The image forming apparatus according to claim 135 , further comprising:
a stepping motor that drives predetermined parts of the image forming apparatus when forming an image onto the recording medium, wherein
the decreasing unit includes a drive control unit that drives the stepping motor in micro-step.
138. The image forming apparatus according to claim 135 , further comprising:
a motor that drives predetermined parts of the image forming apparatus when forming an image onto the recording medium, wherein
the decreasing unit includes a Helmholtz resonator that is disposed near the motor.
139. The image forming apparatus according to claim 135 , further comprising:
a image carrier of a cylindrical shape having a hollow portion; and
a charging unit that charges a surface of the image carrier, wherein
the decreasing unit is disposed in the hollow portion of the image carrier, and includes a damping material that suppresses vibration of the image carrier.
140. The image forming apparatus according to claim 129 , comprising:
a guide member including a flexible sheet that guides the recording medium along a predetermined feeding path, wherein
an edge of the guide member is a bent portion of the flexible sheet, wherein the edge is in contact with the recording medium fed.
141. The image forming apparatus according to claim 135 , wherein a toner used to form an image onto the recording medium contains wax.
142. A method of manufacturing an image forming apparatus that forms an image onto a recording medium, the method comprising:
designing the image forming apparatus so that a discomfort probability P calculated from an equation
P =1/(1+exp(− z ))
where z=A ×(loudness value)+ B ×(sharpness value)+ C ×(tonality value)+ D ×(impulsiveness value)+ E
where 0.76545285≦A≦0.84940259, 1.27685159≦B≦1.48461447, 8.11323413≦C≦9.98398583, 5.30484579≦D≦5.87837423, −14.10339529≦E≦−12.47284396, using loudness, sharpness, tonality, and impulsiveness of a psycho-acoustic parameter obtained from a sound generated from the image forming apparatus when forming an image onto the recording medium satisfies an inequality
P ≦0.3383Ln(ppm)−0.8103,
where 14≦ppm≦38 and ppm is an output number of the recording medium per minute with A4 size in horizontal direction, wherein the sound is collected at a listening position approximately one meter from an edge of the image forming apparatus to be fabricated; and
fabricating the image forming apparatus based on a result of the designing.
143. A method of manufacturing an image forming apparatus that forms an image onto a recording medium, the method comprising:
designing the image forming apparatus so that a discomfort probability P calculated from an equation
P =1/(1+exp(− z ±2σ))
where z=A ×(loudness value)+ B ×(sharpness value)+ C ×(tonality value)+ D ×(impulsiveness value)+ E
where A=0.80742768, B=1.38073296, C=9.04860954, D=5.59160971, and E=−13.28811895, and a standard deviation σ is 0.721307, using loudness, sharpness, tonality, and impulsiveness of a psycho-acoustic parameter obtained from a sound generated from the image forming apparatus when forming an image onto the recording medium satisfies an inequality
P≦ 0.3383Ln(ppm)−0.8103,
where 14≦ppm≦38 and ppm is an output number of the recording medium per minute with A4 size in horizontal direction, wherein the sound is collected at a listening position approximately one meter from an edge of the image forming apparatus to be fabricated; and
fabricating the image forming apparatus based on a result of the designing.
144. A method of manufacturing an image forming apparatus that forms an image onto a recording medium, the method comprising:
designing the image forming apparatus so that a discomfort probability P calculated from an equation
P=1/(1=exp(− z ))
where z=A ×(loudness value)+ B ×(sharpness value)+ C ×(tonality value)+ D ×(impulsiveness value)+ E
where A=0.80742768, B=1.38073296, C=9.04860954, D=5.59160971, and E=−13.28811895, using loudness, sharpness, tonality, and impulsiveness of a psycho-acoustic parameter obtained from a sound generated from the image forming apparatus when forming an image onto the recording medium satisfies an inequality
P ≦0.3383Ln(ppm)−0.8103,
where 14≦ppm≦38, and ppm is an output number of the recording medium per minute with A4 size in horizontal direction, wherein the sound is collected at a listening position approximately one meter from an edge of the image forming apparatus to be fabricated; and
fabricating the image forming apparatus based on a result of the designing.
145. A method of manufacturing an image forming apparatus that forms an image onto a recording medium, the method comprising:
designing the image forming apparatus so that a discomfort probability P calculated from an equation
P =1/(1+exp(− z ))
where z=A =(loudness value)+ B ×(sharpness value)+ C ×(tonality value)+ D ×(impulsiveness value)+ E
where 0.76545285≦A≦0.84940259, 1.27685159≦B≦1.48461447, 8.11323413≦C≦9.98398583, 5.30484579≦D≦5.87837423, −14.10339529≦E≦−12.47284396, using loudness, sharpness, tonality, and impulsiveness of a psycho-acoustic parameter obtained from a sound generated from the image forming apparatus when forming an image onto the recording medium satisfies an inequality
P ≦0.3201Ln( v )−1.2402,
where 62.5≦v≦185, and v is a speed of forming an image onto the recording medium in millimeters per second, wherein the sound is collected at a listening position approximately one meter from an edge of the image forming apparatus to be fabricated; and
fabricating the image forming apparatus based on a result of the designing.
146. A method of manufacturing an image forming apparatus that forms an image onto a recording medium, the method comprising:
designing the image forming apparatus so that a discomfort probability P calculated from an equation
P =1/(1+exp(− z ±2σ))
where z=A ×(loudness value)+ B ×(sharpness value)+ C ×(tonality value)+ D ×(impulsiveness value)+ E
where A=0.80742768, B1.38073296, C9.04860954, D5.59160971, and E=−13.28811895, and a standard deviation σ is 0.72 1307, using loudness, sharpness, tonality, and impulsiveness of a psycho-acoustic parameter obtained from a sound generated from the image forming apparatus when forming an image onto the recording medium satisfies an inequality
P ≦0.3201Ln( v )−1.2402,
where 62.5≦v≦185, and v is a speed of forming an image onto the recording medium in millimeters per second, wherein the sound is collected at a listening position approximately one meter from an edge of the image forming apparatus to be fabricated; and
fabricating the image forming apparatus based on a result of the designing.
147. A method of manufacturing an image forming apparatus that forms an image onto a recording medium, the method comprising:
designing the image forming apparatus so that a discomfort probability P calculated from an equation
P =1/(1+exp(− z ))
where z=A ×(loudness value)+ B ×(sharpness value)+ C ×(tonality value)+ D ×(impulsiveness value)+ E
where A=0.80742768, B=1.38073296, C=9.04860954, D=5.59160971, and E=−13.28811895, using loudness, sharpness, tonality, and impulsiveness of a psycho-acoustic parameter obtained from a sound generated from the image forming apparatus when forming an image onto the recording medium satisfies an inequality
P ≦0.3201Ln( mm/s )−1.2402,
where 62.5≦v≦185, and v is a speed of forming an image onto the recording medium in millimeters per second, wherein the sound is collected at a listening position approximately one meter from an edge of the image forming apparatus to be fabricated; and
fabricating the image forming apparatus based on a result of the designing.
148. A method of modifying an image forming apparatus that forms an image onto a recording medium, the method comprising:
modifying the image forming apparatus so that a discomfort probability P calculated from an equation
P =1/(1+exp(− z ))
where z=A ×(loudness value)+ B ×(sharpness value)+ C ×(tonality value)+ D ×(impulsiveness value)+ E
where A=0.76545285≦A≦0.84940259, 1.27685159≦B≦1.48461447, 8.11323413≦C≦9.98398583, 5.30484579≦D≦5.87837423, −14.10339529≦E≦−12.47284396, using loudness, sharpness, tonality, and impulsiveness of a psycho-acoustic parameter obtained from a sound generated from the image forming apparatus when forming an image onto the recording medium satisfies an inequality
P ≦0.3383Ln(ppm)−0.8103
where 14≦ppm≦38, and ppm is an output number of the recording medium per minute with A4 size in horizontal direction, wherein the sound is collected at a listening position approximately one meter from an edge of the image forming apparatus to be modified.
149. A method of modifying an image forming apparatus that forms an image onto a recording medium, the method comprising:
modifying the image forming apparatus so that a discomfort probability P calculated from an equation
P =1/(1+exp(− z ±2σ))
where z=A ×(loudness value)+ B ×(sharpness value)+ C ×(tonality value)+ D ×(impulsiveness value)+ E
where A=0.80742768, B=1.38073296, C=9.04860954, D=5.59160971, and E=−13.28811895, and a standard deviation σ is 0.72 1307, using loudness, sharpness, tonality, and impulsiveness of a psycho-acoustic parameter obtained from a sound generated from the image forming apparatus when forming an image onto the recording medium satisfies an inequality
P ≦0.3383Ln(ppm)−0.8103,
where 14≦ppm≦38 and ppm is an output number of the recording medium per minute with A4 size in horizontal direction, wherein the sound is collected at a listening position approximately one meter from an edge of the image forming apparatus to be modified.
150. A method of modifying an image forming apparatus that forms an image onto a recording medium, the method comprising:
modifying the image forming apparatus so that a discomfort probability P calculated from an equation
P =1/(1+exp(− z ))
where z=A ×(loudness value)+ B ×(sharpness value)+ C ×(tonality value)+ D ×(impulsiveness value)+ E
where A=0.80742768, B=1.38073296, C=9.04860954, D=5.59160971, and E=−13.28811895, using loudness, sharpness, tonality, and impulsiveness of a psycho-acoustic parameter obtained from a sound generated from the image forming apparatus when forming an image onto the recording medium satisfies an inequality
P ≦0.3383Ln(ppm)−0.8301
where 14≦ppm≦38, and ppm is an output number of the recording medium per minute with A=4 size in horizontal direction, wherein the sound is collected at a listening position approximately one meter from an edge of the image forming apparatus to be modified.
151. A method of modifying an image forming apparatus that forms an image onto a recording medium, the method comprising:
modifying the image forming apparatus so that a discomfort probability P calculated from an equation
P 1/(1+exp(− z ))
where z=A ×(loudness value)+ B ×(sharpness value)+ C ×(tonality value)+ D ×(impulsiveness value)+ E
where 0.76545285≦A≦0.84940259, 1.27685159≦B≦1.48461447, 8.11323413≦C≦9,98398583, 5.30484579≦D≦5.87837423−14.10339529≦E≦−12.47284396, using loudness, sharpness, tonality, and impulsiveness of a psycho-acoustic parameter obtained from a sound generated from the image forming apparatus when forming an image onto the recording medium satisfies an inequality
P≦0.3201Ln( v )−1.2402,
where 62.5≦v≦185, and v is a speed of forming an image onto the recording medium in millimeters per second, wherein the sound is collected at a listening position approximately one meter from an edge of the image forming apparatus to be modified.
152. A method of modifying an image forming apparatus that forms an image onto a recording medium, the method comprising:
modifying the image forming apparatus so that a discomfort probability P calculated from an equation
P =1/(1+exp(− z ±2σ))
where z=A ×(loudness value)+ B ×(sharpness value)+ C ×(tonality value)+ D ×(impulsiveness value)+ E
where A=0.80742768, B=1.38073296, C=9.04860954, D=5.59160971, and E=−13.28811985, and a standard deviation σ is 0.721307, using loudness, sharpness, tonality, and impulsiveness of a psycho-acoustic parameter obtained from a sound generated from the image forming apparatus when forming an image onto the recording medium satisfies an inequality
P ≦0.3201Ln( v )−1.2402,
where 62.5≦v≦185, and v is a speed of forming an image onto the recording medium in millimeters per second, wherein the sound is collected at a listening position approximately one meter from an edge of the image forming apparatus to be modified.
153. A method of modifying an image forming apparatus that forms an image onto a recording medium, the method comprising:
modifying the image forming apparatus so that a discomfort probability P calculated from an equation
P =1/(1+exp(− z ))
where z=A ×(loudness value)+ B ×(sharpness value)+ C ×(tonality value)+ D ×(impulsiveness value)+ E
where A=0.80742768, B=1.38073296, C=9.04860954, D=5.59160971, and E=−13.28811895, using loudness, sharpness, tonality, and impulsiveness of a psycho-acoustic parameter obtained from a sound generated from the image forming apparatus when forming an image onto the recording medium satisfies an inequality
P ≦0.3201Ln( v )−1.2402,
where 62.5≦v≦185, and v is a speed of forming an image onto the recording medium in millimeters per second, wherein the sound is collected at a listening position approximately one meter from an edge of the image forming apparatus to be modified.
154. A method of evaluating sound generated from an image forming apparatus when forming an image onto a recording medium, the method comprising:
evaluating a plurality of kinds of the sound based on a pair comparison method;
performing a logistic regression analysis using discomfort probabilities of two sounds based on the evaluating as a target variable and using a difference between psycho-acoustic parameter values as an explanatory variable;
deriving an equation concerning the discomfort probability of sound quality from a result of the analysis, as follows
P
⋒
ij
=
1
/
{
1
+
exp
[
-
(
∑
l
=
1
L
b
1
(
x
li
-
x
lj
)
)
]
}
where b i is a regression coefficient, x li and x lj are Psycho-acoustic parameter values of two sounds to be compared where i=1,2,3 . . ., n and 1=1,2,3 . . ., L;
substituting an average of the psycho-acoustic parameter values used to derive the equation, into the equation;
defining a probability P as 0.5;
deriving a sound quality evaluation equation to estimate the discomfort probability of the sound; and
evaluating the sound quality using the sound quality evaluation equation derived.
155. A method of manufacturing an image forming apparatus that forms an image onto a recording medium, the method comprising:
evaluating a plurality of kinds of the sound based on a pair comparison method;
performing a logistic regression analysis using discomfort probabilities of two sounds based on the evaluating as a target variable and using a difference between psycho-acoustic parameter values as an explanatory variable;
deriving an equation concerning the discomfort probability of sound quality from a result of the analysis, as follows
P
⋒
ij
=
1
/
{
1
+
exp
[
-
(
∑
l
=
1
L
b
1
(
x
li
-
x
lj
)
)
]
}
where b i is a regression coefficient, x li and x lj are Psycho-acoustic parameter values of two sounds to be compared where i=1,2,3 . . ., n and l=1,2,3 . . ., L;
substituting an average of the psycho-acoustic parameter values used to derive the equation, into the equation;
defining a probability P as 0.5;
deriving a sound quality evaluation equation to estimate the discomfort probability of the sound;
evaluating the sound quality using the sound quality evaluation equation derived;
designing each unit of the image forming apparatus so that a result of the evaluating satisfies a predetermined condition; and
manufacturing the image forming apparatus based on a result of the designing.
156. A method of modifying an image forming apparatus that forms an image onto a recording medium, the method comprising:
evaluating a plurality of kinds of the sound based on a pair comparison method;
performing a logistic regression analysis using discomfort probabilities of two sounds based on the evaluating as a target variable and using a difference between psycho-acoustic parameter values as an explanatory variable;
deriving an equation concerning the discomfort probability of sound quality from a result of the analysis, as follows
P
⋒
ij
=
1
/
{
1
+
exp
[
-
(
∑
l
=
1
L
b
1
(
x
li
-
x
lj
)
)
]
}
where b i is a regression coefficient, x li and x lj are Psycho-acoustic parameter values of two sounds to be compared where i=1,2,3 . . ., n and l=1,2,3 . . ., L;
substituting an average of the psycho-acoustic parameter values used to derive the equation, into the equation;
defining a probability P as 0.5;
deriving a sound quality evaluation equation to estimate the discomfort probability of the sound;
evaluating the sound quality using the sound quality evaluation equation derived; and
modifying corresponding units of the image forming apparatus to be modified based on a result of the evaluating.