Clutch device and image forming apparatus

Patent metadata

Field	Value
Publication number	US-10747166-B2
Application number	US-201816112839-A
Country	US
Kind code	B2
Filing date	Aug 27, 2018
Priority date	Sep 6, 2017
Publication date	Aug 18, 2020
Grant date	Aug 18, 2020

Abstract

A clutch device includes a sector gear, a cam, an electromagnetic solenoid, a first lever, a second lever, a first spring, and a second spring. The cam includes a slide portion. The first lever engages with the electromagnetic solenoid and includes a first restricting portion. The second lever includes a hook and a second restricting portion. The first spring is configured to urge the second lever in a direction in which the first restricting portion and the second restricting portion contact each other. The second spring is configured to, when the electromagnetic solenoid is in a de-energized state, move the first lever. The slide portion of the cam has a surface configured to, when the electromagnetic solenoid is in an energized state, press the hook in a direction opposite to an urging direction of the first spring such that the second restricting portion is separated from the first restricting portion.

First claim

What is claimed is:

1. A clutch device configured to intermittently transmit a rotational force from a drive gear to a rotating member, the clutch device comprising:
a sector gear including a toothless portion, the sector gear being configured to engage with the drive gear;
a cam including an engagement portion and a slide portion, the cam being rotatable integrally with the sector gear;
an electromagnetic solenoid having an energized state and a de-energized state;
a first lever engaging with the electromagnetic solenoid and including a first restricting portion, the first lever being pivotable about a first axis, the first lever being configured to, when the electromagnetic solenoid is in the energized state, move to a first position, the first lever being configured to, when the electromagnetic solenoid is in the de-energized state, move to a second position different from the first position;
a second lever pivotable about a second axis parallel to the first axis, the second lever including:
a hook configured to, when the electromagnetic solenoid is in the de-energized state, engage with the engagement portion of the cam, the hook being configured to, when the electromagnetic solenoid is in the energized state, separate from the engagement portion and slide on the slide portion of the cam; and
a second restricting portion configured to contact or move away from the first restricting portion of the first lever, the second restricting portion being configured to, when the second restricting portion contacts the first restricting portion, restrict movement of the first lever;

a first spring configured to urge the second lever in a direction in which the first restricting portion of the first lever and the second restricting portion of the second lever contact each other; and
a second spring configured to, when the electromagnetic solenoid is in the de-energized state, move the first lever to the second position,
wherein the slide portion of the cam has a surface configured to, when the electromagnetic solenoid is in the energized state, press the hook of the second lever in a direction opposite to an urging direction of the first spring such that the second restricting portion of the second lever is separated from the first restricting portion of the first lever.

2. The clutch device according to claim 1 , wherein an urging force of the first spring is smaller than an urging force of the second spring.

3. The clutch device according to claim 1 , wherein the first axis and the second axis are coaxial with each other.

4. The clutch device according to claim 1 ,
wherein the slide portion of the cam includes:
a first surface configured to, when the electromagnetic solenoid is in the energized state, contact the hook of the second lever; and
a second surface located downstream from the first surface in a direction opposite to a direction of rotation of the cam, and

wherein the second surface is located in a position such that a distance from an axis of the cam to the second surface is greater than a distance from the axis of the cam to the first surface.

5. The clutch device according to claim 4 , further comprising a controller configured to control switching of the electromagnetic solenoid between the energized state and the de-energized state,
wherein the controller is configured to, when the hook of the second lever is in contact with the second surface of the cam, switch the electromagnetic solenoid from the energized state to the de-energized state.

6. The clutch device according to claim 4 ,
wherein the cam includes a third surface located downstream from the second surface in the direction opposite to the direction of rotation of the cam, and
wherein the third surface is shaped such that a distance from the axis of the cam to the third surface gradually decreases the farther the third surface becomes from the second surface in the direction opposite to the direction of rotation of the cam.

7. The clutch device according to claim 1 , wherein, when the hook of the second lever engages with the engagement portion of the cam and the electromagnetic solenoid is switched from the de-energized state to the energized state, the first lever moves from the second position to the first position, the first restricting portion and the second restricting portion contact each other, and the hook of the second lever moves away from the hook of the second lever.

8. The clutch device according to claim 1 ,
wherein the first lever has a first length from the first axis of the first lever to a position in which the first lever engages with the electromagnetic solenoid, and
wherein the second lever has a second length from the second axis of the second lever to the hook, the second length being greater than the first length.

9. An image forming apparatus comprising:
the clutch device according to claim 1 .

Assignees

• Brother Ind Ltd

Inventors

• Tokoro Yuji

Classifications

• G03G21/1647 Primary

  Mechanical connection means · CPC title

• F16H29/12

  between rotary driving and driven members (F16H29/20, F16H29/22 take precedence) · CPC title

• B65H3/0669

  Driving devices therefor · CPC title

• B65H2403/421

  involving at least a gear with toothless portion · CPC title

• B65H2403/724

  electromagnetic clutches · CPC title