Image forming apparatus and control method for image forming apparatus

• US 20030231914A1
• Filed: 06/17/2003
• Published: 12/18/2003
• Est. Priority Date: 06/18/2002
• Status: Active Grant

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation), Toshiba Tec Corporation (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation), Toshiba Tec Corporation (Toshiba Corporation)
• Inventors: Yasui, Kazumasa
• Granted Patent: US 6,931,230 B2
• Time in Patent Office: Days
• US Class Current: 399/396
• CPC Class Codes: G03G 15/231 Arrangements for copying on both sides of a recording or image-receiving material
• CPC Class Codes: G03G 2215/00599 Timing, synchronisation

Abstract

A main CPU effects a control to decrease a reverse convey speed of reverse conveyance by a reverse roller pair when a low-noise mode is set, a control to decrease, where necessary, a reverse convey speed of reverse conveyance by an ADU reverse roller pair, and a control to set a sheet at an optimal reverse position when a convey speed for a fixing device, the reverse roller pair or the ADU reverse roller pair is varied.

Claims

1. An image forming apparatus which forms an image on a paper sheet that is fed, comprising:

a setting section that sets a low-speed mode, relative to a normal mode in the forming of the image;

a first control section that effects, when the low-speed mode is set by the setting section, a control to make a sheet feed interval for successively feeding paper sheets longer than in the normal mode by a predetermined time; and

a second control section that lowers a sheet convey speed at a time of reverse conveyance of the paper sheet in accordance with the sheet feed interval controlled by the first control section.

2. The image forming apparatus according to claim 1, wherein the setting section sets a low-speed mode with less noise than in the image formation in the normal mode set through an operation panel of the image forming apparatus.

3. The image forming apparatus according to claim 1, wherein the first control section delays a sheet feed timing for successively feeding paper sheets by a predetermined time, compared to a sheet feed timing in the normal mode.

4. The image forming apparatus according to claim 1, wherein the second control section controls, at the time of the reverse conveyance of the paper sheet, a reverse convey speed with a less acceleration amount than an acceleration amount of a reverse convey speed in the normal mode.

5. A method of controlling an image forming apparatus which forms an image on a paper sheet that is fed, comprising:

setting a low-speed mode, relative to a normal mode in the forming of the image;

effecting, when the low-speed mode is set, a control to make a sheet feed interval for successively feeding paper sheets longer than in the normal mode by a predetermined time; and

lowering a sheet convey speed at a time of reverse conveyance of the paper sheet in accordance with the sheet feed interval made longer by the predetermined time.

6. An image forming apparatus having an image forming section which forms an image on a paper sheet that is fed, comprising:

a setting section that sets one of an image formation condition relating to double-side image formation and an image formation condition relating to reverse sheet output with single-side image formation;

a reversing section that reverses the paper sheet, on one side of which an image is formed by the image forming section, when the setting section sets one of the image formation condition relating to double-side image formation and the image formation condition relating to reverse sheet output with single-side image formation;

a first control section that controls reverse conveyance by the reversing section with a first reverse convey speed, when the setting section sets the image formation condition relating to double-side image formation and the paper sheet, on one side of which the image is formed by the image forming section, is reversed; and

a second control section that controls the reversing section with a second reverse convey speed different from the first reverse convey speed, when the setting section sets the image formation condition relating to reverse sheet output with single-side image formation and the paper sheet, on one side of which the image is formed by the image forming section, is reversed.

7. The image forming apparatus according to claim 6, wherein the first control section controls the reverse conveyance with a less acceleration amount than an acceleration amount of a predetermined reverse convey speed for reverse conveyance.

8. A method of controlling an image forming apparatus having an image forming section which forms an image on a paper sheet that is fed, comprising:

controlling reverse conveyance with a first reverse convey speed, when formation of images on both sides of the paper sheet is set and the paper sheet, on one side of which an image is formed by the image forming section, is reversed; and

controlling reverse conveyance with a second reverse convey speed different from the first reverse convey speed, when reverse sheet output with formation of an image on one side of the paper sheet is set and the paper sheet, on one side of which an image is formed by the image forming section, is reversed.

9. An image forming apparatus having an image forming section which forms an image on a paper sheet that is fed, comprising:

a first control section that controls a convey speed of the paper sheet on which the image is formed by the image forming section;

a first sensing section that senses the sheet controlled and conveyed by the first control section;

a reversing section that reverses the sheet which comes out of the first sensing section;

a second control section that controls the reversing section at a reverse convey speed corresponding to the convey speed controlled by the first control section;

a second sensing section that senses the sheet which is passing through the reversing section; and

a third control section that controls, when the sheet is sensed by the second sensing section, a sheet reversing operation by the reversing section in accordance with sensing by the first sensing section and the second sensing section.

10. The image forming apparatus according to claim 9, wherein the second control section controls the reversing section at a reverse convey speed that is obtained by accelerating the convey speed controlled by the first control section.

11. The image forming apparatus according to claim 9, wherein the first and second sensing sections are actuator-type sensors.

12. The image forming apparatus according to claim 9, wherein the reversing section reverses the paper sheet with the image formed, when the paper sheet is to be output.

13. The image forming apparatus according to claim 9, wherein the reversing section reverses the paper sheet, on one side of which an image is formed, when images are to be formed on both sides of the paper sheet.

14. The image forming apparatus according to claim 9, wherein when the second sensing section senses the paper sheet, the third control section computes an operation time with which the paper sheet is reversed at an optimal reverse position, on the basis of a time period between the sensing by the first sensing section and the sensing by the second sensing section, the convey speed controlled by the first control section, and the reverse convey speed controlled by the second control section, thereby controlling the sheet reverse operation by the reversing section.

15. A method of controlling an image forming apparatus having an image forming section which forms an image on a paper sheet that is fed, comprising:

setting a convey speed of the paper sheet on which the image is to be formed by the image forming section in accordance with an image forming condition for forming the image on the paper sheet;

setting a reverse convey speed of a reversing section that reverses the paper sheet in accordance with the set convey speed;

sensing, by a first sensing section, the paper sheet which is conveyed at the set convey speed and on which the image is formed by the image forming section; and

computing, when a second sensing section senses that the paper sheet sensed by the first sensing section is conveyed to the reversing section, an operation time with which the paper sheet is reversed at an optimal reverse position, on the basis of the convey speed and the reverse convey speed in accordance with the sensing by the second sensing section and the sensing by the first sensing section, thereby controlling a sheet reverse operation by the reversing section.