Fuser and image forming device including the same
View Patent ↗A fuser includes a first roller that includes a first elastic layer, a belt member provided on, and rotates around, the first roller, a second roller that includes a second elastic layer and that forms a nip part by pressing, through the belt member, the first roller, and a heating member that heats the belt member. A thickness of the second elastic layer of the second roller is less than a thickness of the first elastic layer of the first roller.
1. A fuser, comprising:
a first roller that includes a first core formed in a pipe shape in a cross-section and a first elastic layer formed on an outer periphery side of the first core;
an endless belt member that is provided on and rotates around the first roller;
a second roller that includes a second core formed in a pipe shape in a cross-section and a second elastic layer formed on an outer periphery side of the second core and that forms a nip part by pressing, through the belt member, the first roller; and
a heating member that is positioned on an inner periphery side of the belt member and that heats the belt member, wherein
the first core and the second core are made of substantially the same material,
the first elastic layer and the second elastic layer are made of substantially the same material,
a thickness of the second elastic layer of the second roller is less than a thickness of the first elastic layer of the first roller,
a heat capacity of the second roller is less than a heat capacity of the first roller by 59 or more [J/K ], and
the second roller is heated by the belt member that has been heated by the heating member.
2. The fuser according to claim 1 , wherein
diameters of the first and second elastic layers are substantially identical.
3. The fuser according to claim 1 , wherein
the material of the first and second elastic layers is silicone rubber.
4. The fuser according to claim 1 , wherein
an outer diameter of the second roller is identical to an outer diameter of the first roller.
5. The fuser according to claim 1 , wherein
the first elastic layer of the first roller has a thickness of at least 2 mm.
6. The fuser according to claim 1 , wherein
the first roller is a fusion roller, and
the second roller is a pressure application roller.
7. The fuser according to claim 6 , further comprising:
a pressure member that is provided adjacent to the fusion roller and that presses, through the belt member, the second roller.
8. The fuser according to claim 1 , wherein
the heating member is a sheet heater in a slender shape.
9. The fuser according to claim 8 , wherein
the sheet heater is disposed such that a longitudinal direction of the sheet heater is substantially in an axis of the belt member.
10. The fuser according to claim 1 , wherein
the heating member is a halogen heater.
11. The fuser according to claim 1 , wherein
the silicone rubber of the first elastic layer is foamed.
12. The fuser according to claim 11 , wherein
the silicone rubber of the second elastic layer is not foamed but solid.
13. An image forming device, comprising:
the fuser according to claim 1 .
14. The fuser according to claim 1 , wherein
the thickness of the first elastic layer of the first roller is in a range between 8% and 25% (inclusive) with respect to an outer diameter of the first roller.
15. The fuser according to claim 1 , wherein
the second roller is configured to be driven by the first roller to rotate in a medium carrying direction.
16. The fuser according to claim 1 , wherein
the material of the first core and the second core is aluminum.
17. The fuser according to claim 1 , wherein
the second roller is heated only by the belt member that has been heated by the heating member, and
the heat capacity of the second roller is less than the heat capacity of the first roller thereby an increase in temperature of the second roller is faster than an increase in temperature of the first roller during a warm up period.
18. The fuser according to claim 1 , wherein
the thickness of the second elastic layer of the second roller is 0.25 to 0.8 times of the thickness of the first elastic layer of the first roller.
19. The fuser according to claim 1 , further comprising:
a pad member that is positioned on an upstream side of the nip part in a direction that the belt member rotates, wherein
the pad member includes:
a support base formed of metal,
an elastic material formed to the support base, and
a sliding layer provided on the elastic material.
20. The fuser according to claim 19 , wherein
the support base is made of aluminum.
21. The fuser according to claim 19 , wherein
the first elastic layer of the first roller, the second elastic layer of the second roller, and the elastic material of the pad members are formed by silicone rubber,
the first core of the first roller and the second core of the second roller are formed by an iron material, and
the support base of the pad member is formed by aluminum.
22. A fuser, comprising:
a first roller that includes a first core formed in a pipe shape in a cross-section and a first elastic layer formed on an outer periphery side of the first core;
an endless belt member that is provided on and rotates around the first roller;
a second roller that includes a second core formed in a pipe shape in a cross-section and a second elastic layer formed on an outer periphery side of the second core and that forms a nip part by pressing, through the belt member, the first roller;
a heating member that is positioned on an inner periphery side of the belt member and that heats the belt member;
a pad member that is positioned on an upstream side of the nip part in a direction that the belt member rotates, wherein
the first core and the second core are made of substantially the same material,
the first elastic layer and the second elastic layer are made of substantially the same material,
a thickness of the second elastic layer of the second roller is less than a thickness of the first elastic layer of the first roller,
a thickness of the second core is equal to or less than a thickness of the first core,
the second roller is heated by the belt member that has been heated by the heating member, and
the pad member includes:
a support base formed of metal,
an elastic material formed to the support base, and
a sliding layer provided on the elastic material.
23. The fuser according to claim 22 , wherein
diameters of the first and second elastic layers are substantially identical.
24. The fuser according to claim 22 , wherein
the materials of the first and second elastic layers are silicone rubber.
25. The fuser according to claim 22 , wherein
a heat capacity of the second roller is less than a heat capacity of the first roller.
26. The fuser according to claim 22 , wherein
the first elastic layer of the first roller has a thickness of at least 2 mm.
27. The fuser according to claim 22 , wherein
the first roller is a fusion roller, and the second roller is a pressure application roller.
28. The fuser according to claim 22 , wherein
the heating member is a sheet heater in a slender shape.
29. The fuser according to claim 28 , wherein
the sheet heater is disposed such that a longitudinal direction of the sheet heater is substantially in an axis of the belt member.
30. The fuser according to claim 22 , wherein
the heating member is a halogen heater.
31. The fuser according to claim 22 , wherein
the silicone rubber of the first elastic layer is foamed.
32. The fuser according to claim 31 , wherein
the silicone rubber of the second elastic layer is not foamed but solid.
33. An image forming device, comprising:
the fuser according to claim 22 .
34. The fuser according to claim 22 , wherein
the thickness of the first elastic layer of the first roller is in a range between 8% and 25% (inclusive) with respect to an outer diameter of the first roller.
35. The fuser according to claim 22 , wherein
the second roller is configured to be driven by the first roller to rotate in a medium carrying direction.
36. The fuser according to claim 22 , wherein
the thickness of the first core and the thickness of the second core are substantially identical.
37. The fuser according to claim 22 , wherein
the material of the first core and the second core is aluminum.
38. The fuser according to claim 22 , wherein
the second roller is heated only by the belt member that has been heated by the heating member, and
a heat capacity of the second roller is less than a heat capacity of the first roller by 59 or more [J/K], and thereby an increase in temperature of the second roller is faster than an increase in temperature of the first roller during a warm up period.
39. The fuser according to claim 22 , wherein
the thickness of the second elastic layer of the second roller is 0.25 to 0.8 times of the thickness of the first elastic layer of the first roller.
40. The fuser according to claim 22 , wherein
the support base is made of aluminum.
41. The fuser according to claim 22 , wherein
the first elastic layer of the first roller, the second elastic layer of the second roller, and the elastic material of the pad members are formed by silicone rubber,
the first core of the first roller and the second core of the second roller are formed by an iron material, and
the support base of the pad member is formed by aluminum.