Image Formation Device

• US 20110268484A1
• Filed: 03/29/2011
• Published: 11/03/2011
• Est. Priority Date: 04/28/2010
• Status: Active Grant

• Current Assignee: Brother Kogyo Kabushiki Kaisha
• Original Assignee: Brother Kogyo Kabushiki Kaisha
• Inventors: AOI, Yosuke
• Granted Patent: US 8,660,476 B2
• Time in Patent Office: Days
• US Class Current: 399/397
• CPC Class Codes: B65H 2220/01 indicating an entity as a function of which control, adjustment or change is performed, i.e. input
• CPC Class Codes: B65H 2220/02 indicating an entity which is controlled, adjusted or changed by a control process, i.e. output
• CPC Class Codes: B65H 2220/03 indicating an entity which is measured, estimated, evaluated, calculated or determined but which does not constitute an entity which is adjusted or changed by the control process per se
• CPC Class Codes: B65H 2301/33312 forward reverse rollers pairs
• CPC Class Codes: B65H 2511/20 Location in space
• CPC Class Codes: B65H 2511/518 Particular portion of element
• CPC Class Codes: B65H 2513/10 Speed
• CPC Class Codes: B65H 2513/41 Direction of movement
• CPC Class Codes: B65H 2701/1313 trailing edge
• CPC Class Codes: B65H 2801/06 Office-type machines, e.g. photocopiers
• CPC Class Codes: B65H 85/00 Recirculating articles, i.e. feeding each article to, and delivering it from, the same machine work-station more than once
• CPC Class Codes: G03G 15/234 by inverting and refeeding the image receiving material with an image on one face to the recording member to transfer a second image on its second face, e.g. by using a duplex tray; Details of duplex trays or inverters
• CPC Class Codes: G03G 2215/00438 Inverter of refeeding path
• CPC Class Codes: G03G 2215/00945 Copy material feeding speed varied over the feed path

Abstract

An image formation device is configured such that a feed roller and a discharge roller are rotated in a first direction so that the sheet is fed from the fixing unit to the discharge opening at a first speed V1, in a second direction so that the sheet is fed from the discharge opening to the diverging point at a second speed V2 if the entire sheet has reached a discharge opening side with respect to the diverging point, and the feeding speed is changed to a third speed V3 if the sheet has reached a position where it is nipped by the sheet feed rollers after the sheet was started to be fed at the second speed V2.

Claims

1. An image formation device having an image formation unit that forms an image on a sheet, comprising:

a motor configured to rotate in forward and reverse directions;

a discharge roller configured to be driven by the motor to rotate in forward and reverse directions, the discharge roller feeding the sheet with an image being formed in one surface in a direction of discharged from the image formation device and thereafter feeding the sheet in a direction of introducing the sheet inside the image formation device;

a reverse path that guides the sheet which is fed in the direction of introducing the sheet inside the image formation device to be directed to the image formation unit;

a feed roller arranged in the reverse path and configured to feed the sheet; and

a control unit configured to control the motor such that the sheet feed speed is increased after the sheet reaches the feed roller which is closest to the discharge roller, when the discharge roller is controlled to feed the sheet in the direction of introducing the sheet.

2. The image formation device according to claim 1, wherein the feeding speed after the sheet is reversed is faster than the feeding speed before the sheet is reversed.

3. The image formation device according to claim 1,

wherein a part of the reverse path is used when the sheet is fed toward the discharge roller, and

wherein the feed roller is arranged at a position through which the sheet passes through regardless whether the sheet is fed in the forward direction or in the reverse direction.

4. The image formation device according to claim 1,

wherein the feed roller includes a pair of rollers configured to nip the sheet over a width the direction.

5. The image formation device according to claim 4,

further comprising a fixing unit arranged on a downstream side of the image formation unit and configured to apply heat and pressure to the sheet using a pressure applying member and a pressure applying member, and

wherein the pair of feed rollers made of rubber material.

6. The image formation device according to claim 1, wherein the motor is a stepping motor.

7. The image formation device according to claim 6, wherein the feed rollers are driven by the stepping motor.

8. An image formation device, comprising:

a housing formed with a discharge opening trough which a sheet is discharged from the image formation device;

an image formation unit configured to form an image on the sheet;

a fixing unit configured to fix an image, which was transferred on the sheet, on the sheet;

a sheet feed path which guides the sheet from the fixing unit to the discharge opening;

a sheet feed roller arranged in the sheet feed path;

a sheet discharge roller arranged at a position in the sheet feed path and between the discharge opening and the sheet feed roller;

a motor configured to drive the sheet feed roller and the sheet discharge roller;

a reverse path which is diverged from a diverging point defined at a position in the sheet feed path and between the sheet feed roller and the fixing unit; and

a controller which is configured to;

control the motor to rotate the sheet feed roller and the sheet discharge roller in a first direction so that the sheet is fed from the fixing unit to the discharge opening at a first speed V1;

control the motor to rotate the sheet feed roller and the sheet discharge roller in a second direction so that the sheet is fed from the discharge opening to the diverging point at a second speed V2 if the entire sheet has reached a discharge opening side with respect to the diverging point; and

change the feeding speed to a third speed V3 if the sheet has reached a position where it is nipped by the sheet feed roller after the sheet was started to be fed at the second speed V2.

9. The image formation device according to claim 8, wherein the first speed V1, the second speed V2 and the third speed V3 have the following relationships,

|V1|<

|V3|, and

|V2|<

|V3|.

10. The image formation device according to claim 8, wherein the first speed V1, the second speed V2 and the third speed V3 have the following relationships,

|V1|<

|V2|<

|V3|.

11. The image formation device according to claim 8, wherein the feed roller includes a pair of rollers, longitudinal length of each of the pair of rollers is longer than the width of the sheet.

12. The image formation device according to claim 8, wherein the sheet feed roller includes a pair of rollers, which are made of rubber material.

13. The image formation device according to claim 8, wherein the motor is a stepping motor.

14. The image formation device according to claim 8,

wherein the controller controls the feeding speed of the sheet such that the feeding speed of the sheet is changed to a fourth speed V4 if the entire sheet has passed through the diverging point and entered the reverse path after the sheet was started to be fed at the third speed V3, and

wherein the third speed V3 and the fourth speed V4 have the following relationship;

|V4|<

|V3|.