Sheet processing apparatus and image forming system having plural roller pairs

Patent metadata

Field	Value
Publication number	US-9533853-B2
Application number	US-201514680434-A
Country	US
Kind code	B2
Filing date	Apr 7, 2015
Priority date	May 12, 2014
Publication date	Jan 3, 2017
Grant date	Jan 3, 2017

Abstract

A sheet processing apparatus includes a conveyance roller pair that rotates in a certain direction to convey a sheet, a first normal-reverse rotation roller pair that is capable of rotating in a normal direction and a reverse direction and rotates to convey the sheet, a first driver that drives the first normal-reverse rotation roller pair to rotate, and a first driving force transmitter that transmits a driving force of the first driver for rotating the first normal-reverse rotation roller pair in a first specific direction to the conveyance roller pair so as to rotate the conveyance roller pair in the certain direction, and blocks a driving force of the first driver for rotating the first normal-reverse rotation roller pair in the direction opposite to the first specific direction from being transmitted to the conveyance roller pair.

First claim

What is claimed is:

1. A sheet processing apparatus, comprising:
a conveyance roller pair that rotates in a certain direction to convey a sheet;
a first normal-reverse rotation roller pair that is capable of rotating in a normal direction and a reverse direction and rotates to convey the sheet;
a first driver that drives the first normal-reverse rotation roller pair to rotate;
a first driving force transmitter that transmits a driving force of the first driver for rotating the first normal-reverse rotation roller pair in a first specific direction to the conveyance roller pair so as to rotate the conveyance roller pair in the certain direction, and blocks a driving force of the first driver for rotating the first normal-reverse rotation roller pair in the direction opposite to the first specific direction from being transmitted to the conveyance roller pair;
a second normal-reverse rotation roller pair that is capable of rotating in a normal direction and a reverse direction and rotates to convey the sheet;
a second driver that drives the second normal-reverse rotation roller pair to rotate; and
a second driving force transmitter that transmits a driving force of the second driver for rotating the second normal-reverse rotation roller pair in a second specific direction to the conveyance roller pair so as to rotate the conveyance roller pair in the certain direction, and blocks a driving force of the second driver for rotating the second normal-reverse rotation roller pair in the direction opposite to the second specific direction from being transmitted to the conveyance roller pair.

2. The sheet processing apparatus according to claim 1 , wherein, when the first driver drives the first normal-reverse rotation roller pair to rotate in the first specific direction and the second driver drives the second normal-reverse rotation roller pair to rotate in the second specific direction, out of the first and the second drivers, the driving force of one driver that rotates the conveyance roller pair at a faster speed than the other driver rotates the conveyance roller pair is transmitted to the conveyance roller pair, and the driving force of the other driver is blocked from being transmitted to the conveyance roller pair.

3. The sheet processing apparatus according to claim 1 , further comprising a driving controller that controls driving of the first driver and the second driver, wherein,
when a transmission driver that transmits the driving force to the conveyance roller pair is switched between the first driver and the second driver, the driving controller accelerates a driving speed of a non-transmission driver that does not transmit the driving force to the conveyance roller pair up to certain acceleration until the transmission driver is switched, and when the driving speed of the non-transmission driver reaches the certain acceleration, the driving controller reduces a driving speed of the transmission driver that is transmitting the driving force to the conveyance roller pair.

4. The sheet processing apparatus according to claim 1 , further comprising a folding processing roller pair that rotates while sandwiching surfaces of the sheet being bent to form a fold on the sheet, wherein
the first normal-reverse rotation roller pair bends the sheet toward the folding processing roller pair by conveying one end side of the sheet in a conveyance direction of the sheet to the other end side of the sheet in the conveyance direction while the other end side of the sheet in the conveyance direction is held,
the folding processing roller pair forms the fold on the sheet bent by the first normal-reverse rotation roller pair, and
the second normal-reverse rotation roller pair conveys the sheet on which the fold has been formed.

5. The sheet processing apparatus according to claim 1 , wherein the first driving force transmitter transmits the driving force of the first driver to the conveyance roller pair from when the conveyance roller pair starts to convey the sheet in a forward direction until the first normal-reverse rotation roller pair conveys the sheet in the forward direction by a certain distance.

6. The sheet processing apparatus according to claim 5 , wherein the second driving force transmitter transmits the driving force of the second driver to the conveyance roller pair from when the rotation of the first normal-reverse rotation roller pair is reversed after the first normal-reverse rotation roller pair conveys the sheet in the forward direction by the certain distance until the sheet exits the first normal-reverse rotation roller pair.

7. The sheet processing apparatus according to claim 6 , wherein the first driving force transmitter transmits the driving force of the first driver to the conveyance roller pair from when the rotation of the first normal-reverse rotation roller pair is reversed and the sheet exits the first normal-reverse rotation roller pair until the first normal-reverse rotation roller pair conveys a next sheet in the forward direction by the certain distance.

8. An image forming system, comprising:
an image forming apparatus that performs image forming output on the sheet; and
the sheet processing apparatus according to claim 1 .

9. The sheet processing apparatus according to claim 1 , wherein:
the first driving force transmitter includes a one-way clutch.

10. The sheet processing apparatus according to claim 9 , wherein:
the second driving force transmitter includes a one-way clutch.

Assignees

• Nakagawa Yuuki
• Fukami Kentaroh
• Watanabe Daishi
• Ricoh Co Ltd

Inventors

• Nakagawa Yuuki
• Fukami Kentaroh
• Watanabe Daishi

Classifications

• B65H45/14 Primary

  Buckling folders · CPC title

• B65H2403/72

  Clutches, brakes, e.g. one-way clutch +F204 · CPC title

• B65H2403/942

  Bidirectional powered handling device · CPC title

• B65H2404/166

  reverse roller · CPC title

• B65H2220/09

  indicating that several of an entity are present · CPC title