Sheet transport with one-way clutch to disengage separation shaft

Patent metadata

Field	Value
Publication number	US-10081507-B2
Application number	US-201715407959-A
Country	US
Kind code	B2
Filing date	Jan 17, 2017
Priority date	Jan 17, 2017
Publication date	Sep 25, 2018
Grant date	Sep 25, 2018

Abstract

In one example in accordance with the present disclosure, a sheet transport device is described. The sheet transport device includes a pickup roller to insert a sheet into a sheet path. A pair of separation rollers of the sheet transportation device form a nip that advances the sheet along the sheet path. A first separation shaft on which a first separation roller is disposed rotates in a first direction as the sheet is advanced and a second separation shaft on which a second separation roller is disposed also rotates in the first direction as the sheet is advanced. The second separation roller is driven in a second direction via a torque limiter. A motor rotates the shafts. A one-way clutch is disposed on the second separation shaft to disengage the second separation shaft from the motor when the motor is operating in a reverse mode.

First claim

What is claimed is:

1. A sheet transport device comprising:
a pickup roller to insert a sheet of media into a sheet path;
a pair of separation rollers including a first separation roller and a second separation roller and forming a nip to advance the sheet along the sheet path, wherein:
a first separation shaft, driven by a motor, on which the first separation roller is disposed rotates in a first direction as the sheet is advanced along the sheet path;
a second separation shaft, engaged with the motor via a one-way clutch disposed on the second separation shaft, on which the second separation roller is disposed, rotates in the first direction as the sheet is advanced along the sheet path; and
the second separation roller is driven by the second separation shaft in a second direction as the sheet is advanced along the sheet path in response to a torque limiter coupling the second separation shaft to the second separation roller, such that the second separation shaft rotates in the first direction and the second separation roller is driven in the second direction,

wherein the one-way clutch disengages the second separation shaft from the motor when the motor is operating in a reverse mode.

2. The device of claim 1 , wherein, responsive to a presence of more than one sheet in the nip and the torque limiter reaches a predetermined breakaway torque, the torque limiter disengages the second separation shaft from the second separation roller, such that the second separation roller rotates in the first direction as a first sheet is advanced along the sheet path.

3. The device of claim 1 , wherein:
the first separation shaft is on top of the sheet as the sheet advances along the sheet path; and
the second separation shaft is on bottom of the sheet as the sheet advances along the sheet path.

4. The device of claim 1 , wherein responsive to the motor being operated in the reverse mode, the torque limiter is disengaged.

5. The device of claim 1 , wherein the motor:
when operating in a forward mode:
drives the pickup roller and the first separation roller in the first direction; and
drives the second separation roller in the second direction; and

when operating in the reverse mode:
drives the first separation roller in the second direction; and
is disengaged from the second separation roller and the pickup roller.

6. The device of claim 5 , wherein the motor:
when operating in the forward mode is disengaged from a transport path shaft; and
when operating in the reverse mode drives the transport path shaft to advance a second sheet along the sheet path.

7. The device of claim 1 , wherein the first separation shaft is clutchlessly coupled to the motor.

8. A sheet transport system comprising:
a sheet transport device comprising:
a pickup roller to insert a sheet from a sheet tray into a sheet path;
a pair of separation rollers including a first separation roller and a second separation roller and forming a nip to advance the sheet along the sheet path;
a torque limiter disposed on a second separation shaft; and
a one-way clutch disposed on the second separation shaft; and
a motor; and

a transport path roller to advance a sheet not originating from the sheet tray along the sheet path;
wherein the motor is to:
rotate in a forward direction to drive the pickup roller, the first separation roller and the second separation roller; and
rotate in a reverse direction to drive the first separation roller and the transport path roller.

9. The system of claim 8 , wherein a first separation shaft is directly coupled to the motor.

10. The system of claim 8 , wherein a first separation shaft is fixedly coupled to the motor to be driven in a forward direction and a reverse direction.

11. A method for transporting a sheet, comprising:
driving a motor in a forward mode to rotate a pickup roller, a first separation shaft, and a second separation shaft in a first direction while a transport path shaft is inactive;
driving a second separation roller disposed on the second separation shaft in a second direction in response to a torque limiter coupling the second separation shaft to the second separation roller; and
driving the motor in a reverse mode to rotate the first separation shaft in a second direction and to activate the transport path shaft while the pickup roller and second separation shaft are disengaged.

12. The method of claim 11 , wherein the motor is driven in the reverse mode responsive to a termination of a print job.

13. The method of claim 11 , wherein the motor is driven in the reverse mode after being idle for a predetermined period of time.

14. The method of claim 11 , wherein driving the second separation roller in the second direction comprises disengaging the torque limiter with just an electrical stimulus to reverse the motor.

15. The method of claim 11 , further comprising driving a transport path shaft by driving the motor in the reverse mode.

Assignees

• Hewlett Packard Development Co

Inventors

• Nameroff Alexander M
• Uehling Devin Scott

Classifications

• B65H3/5246

  Driven retainers, i.e. the motion thereof being provided by a dedicated drive · CPC title

• B65H3/5253

  the retainers positioned under articles separated from the top of the pile · CPC title

• B65H3/5215

  the retainers positioned under articles separated from the top of the pile · CPC title

• B65H3/5207

  Non-driven retainers, e.g. movable retainers being moved by the motion of the article · CPC title

• B65H3/52 Primary

  Friction retainers acting on under or rear side of article being separated · CPC title