Tube pump and liquid ejection apparatus

Patent metadata

Field	Value
Publication number	US-10744784-B2
Application number	US-201816056861-A
Country	US
Kind code	B2
Filing date	Aug 7, 2018
Priority date	Aug 10, 2017
Publication date	Aug 18, 2020
Grant date	Aug 18, 2020

Abstract

The present invention is intended to provide a tube pump which can suppress occurrence of a back flow of liquid in a tube at the time of reverse rotation of a second rotating body, with a simple configuration. The tube pump includes a tube; a case; a roller making a specific movement; a first rotating body having a guiding part which guides the roller in an arc radial direction of the arc-shaped wall surface of the case; and a second rotating body having a roller position regulating part acting on a position in an arc radial direction of the arc-shaped wall surface of the case of the roller.

First claim

What is claimed is:

1. A tube pump comprising:
a tube having elastic restoring force;
a case supporting a part of the tube along a wall surface;
a roller capable of moving between a first position in which the roller presses the tube to the wall surface and a second position in which the roller does not press the tube to the wall surface;
a first rotating body having a guiding part for transmitting a rotational driving force to the roller, the roller being guided by the guiding part as the roller moves between the first position and the second position;
a second rotating body having (i) a regulating part for regulating a position of the roller and configured to move the roller to the first position and (ii) a drive transmitting part for transmitting a rotational driving force to the first rotating body;
wherein, when the second rotating body is rotated in a first direction, the drive transmitting part is configured to rotate the first rotating body and the regulating part is configured to move the roller to the first position as the roller is guided by the guiding part, and
wherein, when the second rotating body is rotated in a second direction opposite to the first direction from a state in which the regulating part regulates the roller to the first position, the regulating part is configured to release regulating the roller to the first position while the drive transmitting part changes from a state in which the drive transmitting part does not transmit a drive to the first rotating body to a state in which the drive transmitting part transmits a drive to the first rotating body.

2. The tube pump according to claim 1 , wherein the wall surface is arc-shaped,
wherein the roller has a cylindrical part acting on the tube, the cylindrical part having a first end, a second end and a shaft, the shaft provided on each of the first end and the second end of the cylindrical part,
wherein the first rotating body has two plane members sandwiching the cylindrical part of the roller in a direction of the shaft, and
wherein the guiding part of the first rotating body includes an elongated hole on each of the two plane members, the elongated hole being elongated in a radial direction of the arc-shaped wall surface, each elongated hole guiding the shaft of the roller.

3. The tube pump according to claim 2 , wherein each elongated hole includes a first end and a second end, the first end of the respective elongated hole being an end proximate to the arc-shaped wall surface,
wherein, when the roller is in the first position, the shaft of the roller is positioned at the first end of each elongated hole, and
wherein, when the roller is in the second position, the shaft of the roller is positioned at the second end of each elongated hole.

4. The tube pump according to claim 2 , wherein each of the two plane members includes an arc-shaped elongated hole centered on a rotation center of the first rotating body,
wherein the drive transmitting part includes a plurality of protrusions, each of the protrusions engaging the arc-shaped elongated hole provided on the two plane members and being configured to move in elongated hole as the second rotating body rotates, and wherein, when each protrusion is positioned at an end portion of the elongated hole, the protrusion presses end portion of the elongated hole, thereby rotating the first rotating body by rotational driving force of the second rotating body.

5. The tube pump according to claim 2 , wherein the regulating part acts on the shaft.

6. The tube pump according to claim 2 , wherein the regulating part acts on the cylindrical part.

7. The tube pump according to claim 1 , wherein the regulating part includes a regulating surface defining a position of the roller in the guiding part from the second position to the first position, the regulating surface having (i) a portion in which the radial distance of the regulating surface from a rotation center of the second rotating body is gradually changed over a predetermined rotation angle in a circumferential direction of the second rotating body, and (ii) a portion in which the regulating surface has a constant radial distance from the rotation center of the second rotating body over another predetermined rotation angle in the circumferential direction of the second rotating body.

8. The tube pump according to claim 7 , wherein the radial distance of the regulating surface is changed by a total radial distance and each elongated hole has a length, the total radial distance being less than the length of the elongated hole.

9. The tube pump according to claim 1 , wherein the regulating part is formed integrally with the second rotating body.

10. The tube pump according to claim 1 , wherein the regulating part is maintained so that the side of the second rotating body close to a rotation center of the second rotating body is pivotally supported on the second rotating body, and
wherein the side of the second rotating body distant from the rotation center of the second rotating body is maintained swingably and is urged in a direction of away from the rotation center of the second rotating body by an urging member provided between the regulating part and another portion of the second rotating body.

11. The tube pump according to claim 1 , wherein the roller has a cylindrical part acting on the tube, the cylindrical part having a first end, a second end and a shaft, the shaft provided on each of the first end and the second end of the cylindrical part,
wherein the roller is held by a roller holding lever including as roller holding part engaged with the shaft of the roller, (ii) an action part receiving an action of the regulating part of the second rotating body, and (iii) a swing shaft configured to swinging the roller when the action part receives an action of the regulating part, and
wherein the first rotating body has two plane members sandwiching the roller holding lever in a direction of the shaft, each of the plane members including a swing bearing for holding the swing shaft of the roller holding lever, a portion of the guiding part being provided on each of the plane members.

12. The tube pump according to claim 11 , wherein the wall surface is arc-shaped,
wherein the guiding part includes an elongated hole on each of the two plane members, the elongated hole (i) having the shape of an arc centered on the swing shaft of the roller holding lever, and being elongated in a radial direction of the arc-shaped wall surface of the case, and
wherein the shaft of the roller is engaged with the roller holding part of the roller holding lever and each of the elongated holes.

13. The tube pump according to claim 12 , wherein each elongated hole includes a first end and a second end, the first end of the respective elongated hole being an end proximate to the arc-shaped wall surface,
wherein, when the roller is in the first position, the shaft of the roller is positioned at the first end of each elongated hole, and
wherein, when the roller is in the second position, the shaft of the roller is positioned at the second end of each elongated hole.

14. The tube pump according to claim 13 , wherein each of the two plane members includes an arc-shaped elongated hole centered on a rotation center of the first rotating body,
wherein the drive transmitting part includes a plurality of protrusions, each of the protrusions engaging the arc-shaped elongated hole provided on the two plane members and being configured to move in elongated hole as the second rotating body rotates, and
wherein, when each protrusion is positioned at an end portion of the elongated hole,

Assignees

• Canon Kk

Inventors

• Yokoi Katsuyuki

Classifications

• B41J2/16508

  connected with the printer frame · CPC title

• F04B43/1253

  by using two or more rollers as squeezing elements, the rollers moving on an arc of a circle during squeezing · CPC title

• B41J2/16523

  Waste ink transport from caps or spittoons, e.g. by suction (Collecting or collectors of waste ink B41J2/1721) · CPC title

• B41J2/17596 Primary

  Ink pumps, ink valves · CPC title

• F04B43/1276

  Means for pushing the rollers against the tubular flexible member · CPC title