Development cartridge having a switch member to rotate developing unit to a development position

Patent metadata

Field	Value
Publication number	US-10698362-B2
Application number	US-201715614152-A
Country	US
Kind code	B2
Filing date	Jun 5, 2017
Priority date	Nov 14, 2016
Publication date	Jun 30, 2020
Grant date	Jun 30, 2020

Abstract

Provided is a development cartridge mounted on a main body of an image forming apparatus. The development cartridge includes a photoconductive unit, a developing unit coupled to the photoconductive unit so as to rotate to a development position and a release position, and an elastic member that provides an elastic force to maintain the developing unit at the development position. A switching member is mounted on a rotation shaft of the developing roller to be rotatable about a rotation shaft of a developing roller. The switching member is switched to a first state where the switching member contacts an interfering portion of the photoconductive unit and rotates the developing unit to the release position and to a second state where the switching member is separated from the interfering portion and allows the developing unit to rotate to the development position due to the elastic force of the elastic member.

First claim

What is claimed is:

1. A development cartridge detachable from a main body of an image forming apparatus, the development cartridge comprising:
a photoconductive unit including a photoconductive drum and an interfering portion;
a developing unit including a developing roller having a rotation shaft and coupled to the photoconductive unit to be rotatable
to a release position where the developing roller is separated from the photoconductive drum, and
to a development position where the developing roller contacts the photoconductive drum;

an elastic member to provide an elastic force to maintain the developing unit at the development position;
a coupler separate from the photoconductive drum and couplable to a driving motor provided in the main body when the development cartridge is detachably mounted on the main body, to be rotatable in a first coupler direction and a second coupler direction when the coupler is coupled to the driving motor; and
a switching member mounted on the rotation shaft of the developing roller to be rotatable about the rotation shaft of the developing roller by being coupled to the coupler, to be switchable to:
a first state when the coupler is rotated in the first coupler direction, the first state where the switching member is to contact the interfering portion of the photoconductive unit to rotate the developing unit to the release position, and
a second state when the coupler is rotated in the second coupler direction, the second state where the switching member is to be separated from the interfering portion of the photoconductive unit to allow the developing unit to rotate to the development position due to the elastic force of the elastic member.

2. The development cartridge of claim 1 , wherein the switching member includes:
a driving gear having a rotation axis and provided to be rotatable about the rotation shaft of the developing roller by being coupled to the coupler;
a cam member including a cam portion and a partial gear portion, the partial gear portion to be selectively interlocked with the coupler, and the cam member is provided to be coaxial with the rotation axis of the driving gear and rotatable; and
a clutch member to connect the cam member to the driving gear such that, when the driving gear rotates in at least one of two driving gear directions, the clutch member connects the cam member to the driving gear and the cam member rotates with the driving gear,
wherein, when the partial gear portion of the cam member interlocks with the coupler, the switching member switches to:
the first state by the cam member rotating to a first position where the cam portion contacts the interfering portion of the photoconductive unit to rotate the developing unit to the release position, and
the second state by the cam member rotating to a second position where the cam portion is separated from the interfering portion of the photoconductive unit to allow the developing unit to rotate from the release position to the development position due to the elastic force of the elastic member.

3. The development cartridge of claim 2 , wherein
the driving gear rotates in a first driving gear direction among the at least one of two driving gear directions during printing and rotates in a second driving gear direction among the at least one of two driving gear directions during non-printing, and
the cam member rotates to the second position and the first position when the driving gear rotates in the first driving gear direction and the second driving gear direction, respectively.

4. The development cartridge of claim 3 , further comprising a first stopper and a second stopper to contact the cam portion to stop the cam member from rotating beyond the first position and the second position, respectively, when the cam member is rotated to the first position and the second position, respectively,
wherein the clutch member includes a friction member to provide a frictional force between the cam member and the driving gear.

5. The development cartridge of claim 4 , wherein, when the cam member is at the first position and the second position, the partial gear portion is separated from the coupler.

6. The development cartridge of claim 4 , wherein
the cam member includes a first member including the partial gear portion, and a second member including the cam portion, and the second member is rotated by being pushed by the first member, and
when the cam member is at the first position and the second position, the partial gear portion is separated from the coupler.

7. The development cartridge of claim 6 , wherein
the first member includes a first end and a second end that push the second member when the first member rotates in the first driving gear direction and the second driving gear direction, respectively,
the second member includes a third end and a fourth end corresponding to the first end and the second end, respectively, and
an angle between the third end and the fourth end is greater than an angle between the first end and the second end.

8. The development cartridge of claim 3 , wherein the clutch member includes:
a latch portion and a guiding portion having a long hole shape, provided on the cam member;
a first inner gear portion provided on the driving gear; and
a latch gear interlocking with the first inner gear portion, provided on the guiding portion of the cam member, and interlocking with the latch portion such that
the cam member rotates together with the driving gear, when the driving gear rotates in the second driving gear direction, and
the cam member is separated from the latch portion, when the driving gear rotates in the first driving gear direction.

9. The development cartridge of claim 8 , further comprising
a stopper to contact the cam portion to stop the cam member from rotating beyond the second position when the cam member is rotated to the second position,
wherein
when the cam member is at the first position, the partial gear portion is in mesh with the coupler, and
when the cam member is at the second position, the partial gear portion is separated from the coupler.

10. The development cartridge of claim 3 , wherein the clutch member includes:
a latch member positioned on a same axis as the rotation axis of the driving gear between the driving gear and the cam member, and movable in an axial direction;
a first protrusion provided on the driving gear;
a concave portion provided on the latch member such that the first protrusion fits onto the concave portion, and the concave portion includes
a first opposite surface and a second opposite surface that the first protrusion respectively contacts when the driving gear rotates in the first driving gear direction and the second driving gear direction to thereby rotate the latch member in a first latch member direction and a second latch member direction, respectively, and
a connecting surface that connects the first opposite surface and the second opposite surface to each other and guides the first protrusion such that, when the driving gear rotates in the second driving gear direction, the latch member is pushed toward the cam member; and

first and second latch portions respectively provided on the latch member and the cam member, and
separated from each other when the latch member rotates in the first latch member direction and
interlocking with each other when the latch member rotates in the second latch member direction such that the cam member rotates with the latch member.

11. The development cartridge of claim 10 , wherein the connecting surface includes an inclined surface of which a depth gradually decreases starting from the first opposite sur

Assignees

• Hp Printing Korea Co Ltd
• Hewlett Packard Development Co

Inventors

• Lee Sang-Hoon
• Yang Seung-Beom
• Lee Seung-Gweon

Classifications

• G03G2221/1657

  transmitting mechanical drive power · CPC title

• G03G21/1647 Primary

  Mechanical connection means · CPC title

• F16H53/02

  Single-track cams for single-revolution cycles; Camshafts with such cams · CPC title

• F16H19/001

  for conveying reciprocating or limited rotary motion · CPC title

• F16D11/08

  actuated by moving a non-rotating part axially · CPC title