Liquid ejecting head and liquid ejecting apparatus
A liquid ejecting head includes a nozzle. A sectional shape at a first-position in the nozzle in an ejection-direction is a first-external-shape, and a straight line extending in a second-direction orthogonal to both the ejection-direction and a first-direction being a longitudinal-direction of the first-external-shape and passing through a center of the first-external-shape in the first-direction is a first-center-line. A first-width corresponding to a maximum width in the second-direction in a portion of the first-external-shape on one side in the first-direction with respect to the first-center-line is at a third-position in the first-direction. A second-width corresponding to a maximum width in the second-direction in a portion of the first-external-shape on the other side in the first-direction with respect to the first-center-line is at a fourth-position in the first-direction. A distance between the third-position and the fourth-position is greater than the first-width and the second-width.
1 . A liquid ejecting head comprising:
a nozzle plate including a plurality of nozzles, the plurality of nozzles penetrating the nozzle plate and include a first nozzle configured to eject a liquid in an ejection direction;
a communication plate that includes a first coupling channel connected to the first nozzle and that is disposed on a surface of the nozzle plate facing a direction that is opposite to the ejection direction, the first coupling channel including a first pressure chamber; and
a first driving element located in the direction that is opposite to the ejection direction with respect to the first pressure chamber and configured to generate pressure in the first pressure chamber for ejecting the liquid from the first nozzle, wherein
a certain position in the first nozzle regarding the ejection direction is a first position,
a sectional shape of the first nozzle perpendicular to the ejection direction at the first position is a first external shape,
a longitudinal direction of the first external shape, which is orthogonal to the ejection direction, is a first direction,
a direction orthogonal to both the ejection direction and the first direction is a second direction,
a straight line extending in the second direction and passing through a center of the first external shape regarding the first direction is a first center line,
a first width corresponding to a maximum width regarding the second direction in a portion of the first external shape on one side in the first direction with respect to the first center line is at a third position serving as a certain position regarding the first direction,
a second width corresponding to a maximum width regarding the second direction in a portion of the first external shape on an other side in the first direction with respect to the first center line is at a fourth position serving as a certain position regarding the first direction,
a first distance between the third position and the fourth position regarding the first direction is greater than the first width and greater than the second width, wherein a value obtained by dividing the first width by the first distance is equal to or more than 0.775,
a third width corresponding to a width of the first external shape regarding the second direction at the center regarding the first direction is narrower than the first width and narrower than the second width,
a fifth width corresponding to a width of the first external shape regarding the second direction at a fifth position serving as a certain position between the first center line and the third position is wider than the third width,
a sixth width corresponding to a width of the first external shape regarding the second direction at a sixth position serving as a certain position between the first center line and the fourth position is wider than the third width,
the first external shape includes a connecting portion located between the third position and the fourth position, the connecting portion having a fourth width in the second direction, the fourth width being substantially constant within the entire connecting portion in the first direction, and
a seventh width that is an entire width of the connecting portion in the first direction is narrower than the first width and narrower than the second width.
2 . The liquid ejecting head according to claim 1 , wherein
a certain position between the first center line and the third position regarding the first direction is a seventh position
a certain position between the first center line and the fourth position regarding the first direction is an eighth position, and
a fourth width corresponding to a width of the first external shape regarding the second direction at a position located from the seventh position to the eighth position is substantially constant.
3 . The liquid ejecting head according to claim 1 , wherein
a certain position between the first center line and the third position regarding the first direction is a ninth position,
a certain position between the first center line and the fourth position regarding the first direction is a tenth position,
a distance between the first external shape and a first center of the first width is substantially constant on the one side of the first external shape in the first direction with respect to the ninth position, and
a distance between the first external shape and a second center of the second width is substantially constant on the other side of the first external shape in the first direction with respect to the tenth position.
4 . The liquid ejecting head according to claim 1 , wherein
a certain position between the first center line and the third position regarding the first direction is a seventh position,
a certain position between the first center line and the fourth position regarding the first direction is an eighth position,
a width of the first external shape regarding the second direction at a position located from the seventh position to the eighth position is a fourth width, and
an average value of values obtained by dividing the first width by the fourth width, from the seventh position to the eighth position, is equal to or more than 2.
5 . The liquid ejecting head according to claim 1 , wherein
a certain position upstream of the first position in the first nozzle regarding the ejection direction is a second position,
a sectional shape of the first nozzle perpendicular to the ejection direction at the second position is a second external shape different from the first external shape, and
the second external shape has a size in which the first external shape is included.
6 . The liquid ejecting head according to claim 1 , wherein
a certain position downstream of the first position in the first nozzle regarding the ejection direction is a second position,
a sectional shape of the first nozzle perpendicular to the ejection direction at the second position is a second external shape different from the first external shape, and
the second external shape has an oval shape in which a longitudinal direction is the first direction.
7 . The liquid ejecting head according to claim 1 , further comprising a second driving element, wherein
the first coupling channel includes
a second pressure chamber;
the second driving element is configured to generate pressure in the second pressure chamber for ejecting the liquid from the first nozzle and is located in the direction that is opposite to the ejection direction with respect to the second pressure chamber; and
a communication channel extending in the first direction, through which the first pressure chamber and the second pressure chamber communicate, wherein
the first nozzle is provided halfway in the communication channel, and
a flow direction of liquid flowing through the communication channel from the first pressure chamber to the second pressure chamber is the first direction.
8 . The liquid ejecting head according to claim 1 , wherein the liquid to be supplied to the first nozzle has a viscosity of 20 mPa·s or less at 25° C.
9 . A liquid ejecting apparatus comprising:
the liquid ejecting head according to claim 1 , and
a liquid tank in which the liquid to be supplied to the liquid ejecting head is stored.
10 . A liquid ejecting apparatus comprising:
the liquid ejecting head according to claim 1 , and
a liquid tank in which the liquid to be supplied to the liquid ejecting head is stored.
11 . A liquid ejecting head comprising:
a nozzle plate including a plurality of nozzles, the plurality of nozzles penetrating the nozzle plate and including a first nozzle configured to eject a liquid in an ejection direction;
a communication plate that includes a first coupling channel connected to the first nozzle and that is disposed on a surface of the nozzle plate facing a direction that is opposite to the ejection direction, the first coupling channel including a first pressure chamber, a second pressure chamber, and a communication channel;
a first driving element located in the direction that is opposite to the ejection direction with respect to the first pressure chamber and configured to generate pressure in the first pressure chamber for ejecting the liquid from the first nozzle; and
a second driving element located in the direction that is opposite to the ejection direction with respect to the second pressure chamber and configured to generate pressure in the second pressure chamber for ejecting the liquid from the first nozzle, wherein
the communication channel extends in a first direction, through which the first pressure chamber and the second pressure chamber communicate,
the first nozzle is provided halfway in the communication channel,
a certain position in the first nozzle regarding the ejection direction is a first position,
a sectional shape of the first nozzle perpendicular to the ejection direction at the first position is a first external shape,
a longitudinal direction of the first external shape, which is orthogonal to the ejection direction, is the first direction,
a direction orthogonal to both the ejection direction and the first direction is a second direction,
a straight line extending in the second direction and passing through a center of the first external shape regarding the first direction is a first center line,
a first width corresponding to a maximum width regarding the second direction in a portion of the first external shape on one side in the first direction with respect to the first center line is at a third position serving as a certain position regarding the first direction,
a second width corresponding to a maximum width regarding the second direction in a portion of the first external shape on an other side in the first direction with respect to the first center line is at a fourth position serving as a certain position regarding the first direction,
a first distance between the third position and the fourth position regarding the first direction is greater than the first width and greater than the second width, and
a flow direction of liquid flowing through the communication channel from the first pressure chamber to the second pressure chamber is the first direction.
12 . A liquid ejecting head comprising:
a nozzle plate including a plurality of nozzles, the plurality of nozzles penetrating the nozzle plate and including a first nozzle configured to eject a liquid in an ejection direction;
a communication plate that includes a first coupling channel connected to the first nozzle and that is disposed on a surface of the nozzle plate facing a direction that is opposite to the ejection direction, the first coupling channel including a first pressure chamber; and
a first driving element located in the direction that is opposite to the ejection direction with respect to the first pressure chamber and configured to generate pressure in the first pressure chamber for ejecting the liquid from the first nozzle, wherein
a certain position in the first nozzle regarding the ejection direction is a first position,
a sectional shape of the first nozzle perpendicular to the ejection direction at the first position is a first external shape,
a longitudinal direction of the first external shape, which is orthogonal to the ejection direction, is a first direction,
a direction orthogonal to both the ejection direction and the first direction is a second direction,
a straight line extending in the second direction and passing through a center of the first external shape regarding the first direction is a first center line,
a first width corresponding to a maximum width regarding the second direction in a portion of the first external shape on one side in the first direction with respect to the first center line is at a third position serving as a certain position regarding the first direction,
a second width corresponding to a maximum width regarding the second direction in a portion of the first external shape on an other side in the first direction with respect to the first center line is at a fourth position serving as a certain position regarding the first direction,
a certain position between the first center line and the third position regarding the first direction is a seventh position,
a certain position between the first center line and the fourth position regarding the first direction is an eighth position,
a fourth width corresponding to a width of the first external shape regarding the second direction at a position located from the seventh position to the eighth position is substantially constant,
the first external shape includes a first portion of the first external shape on the one side in the first direction with respect to the seventh position and a second portion on the other side in the first direction with respect to the eighth position, and
a first distance between the third position and the fourth position regarding the first direction is greater than the first width and greater than the second width such that a first liquid droplet ejected from the first portion and a second liquid droplet ejected from the second portion are ejected in directions that approach each other and are united before liquid landing on a medium.