Sheet supplying apparatus

• US 5,571,265 A
• Filed: 01/13/1995
• Issued: 11/05/1996
• Est. Priority Date: 06/19/1992
• Status: Expired due to Term

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Yagi, Tadashi, Tomura, Hisayuki, Morinaga, Kazuyuki, Sootome, Sumitoshi, Kikuchi, Yutaka
• Primary Examiner(s): SKAGGS JR, H GRANT
• Application Number:
  US08/372,830
• Time in Patent Office: 662 Days
• Field of Search: 271/119, 271/122, 271/126, 271/127, 271/10, 271/116, 271/114, 271/170
• US Class Current: 271/119
• CPC Class Codes: B65H 3/0669 Driving devices therefor
• CPC Class Codes: B65H 3/5261 Retainers of the roller type, e.g. rollers

Abstract

The present invention provides a sheet supplying apparatus having a sheet stacking device for stacking and supporting sheets, a sheet supply roller having different radial dimensions along a periphery thereof to feed out the sheets from the sheet stacking device, and a separation unit having a feed rotary member rotated in a sheet feeding direction and a reverse rotary member rotated in a direction opposite to the sheet feeding direction to separate the sheets fed out by the sheet supply roller one by one.

Claims

1. A sheet supplying apparatus, comprising

sheet stacking means for supporting sheets;

a sheet supply roller having different radial dimensions along a periphery thereof for feeding out the sheets from said sheet stacking means;

separation means comprising a feed rotary member rotatable in a sheet feeding direction and a reverse rotary member rotatable in a direction opposite to the sheet feeding direction, for separating the sheets fed out by said sheet supply roller one by one;

driving means for generating a rotation drive force to rotate said sheet supply roller and the rotary members of said separation means;

first rotation transmitting means for transmitting the rotation force of said driving means to the reverse rotary member;

second rotation transmitting means for transmitting the rotation force of said driving means to said sheet supply roller and to the feed rotary member; and

rotation controlling means provided in said second rotation transmitting means for interrupting transmission of the rotation drive force from said driving means to said sheet supply roller, after a predetermined amount of rotation of said sheet supply roller, to thereby stop rotation of said sheet supply roller and the feed rotary member.

2. A sheet supplying apparatus according to claim 1, wherein said sheet supply roller is urged against an uppermost sheet among the sheets stacked in said sheet stacking means to feed out the sheets.

3. A sheet supplying apparatus according to claim 2, wherein said sheet stacking means includes a spring for biasing the sheets stacked in said sheet stacking means toward said sheet supply roller, and a regulating member for maintaining the uppermost sheet in a given position in opposition to a biasing force of said spring.

4. A sheet supplying apparatus according to claim 1, wherein said sheet supply roller having different radial dimensions along the periphery thereof is a semi-circular roller.

5. A sheet supplying apparatus according to claim 1, further comprising convey means for conveying the sheet separated by said separation means, said convey means being driven by rotation force transmitted through said first rotation transmitting means.

6. A sheet supplying apparatus according to claim 5, wherein rotation said feed rotary member is stopped after a tip end of the separated sheet reaches to said convey means.

7. A sheet supplying apparatus according to claim 1, wherein said feed rotary member is connected to said second rotation transmitting means via a one-way clutch.

8. A sheet supplying apparatus according to claim 1, wherein each of said first and second rotation transmitting means has a gear train.

9. A sheet supplying apparatus according to claim 1, wherein said rotation controlling means is a spring clutch.

10. An image forming apparatus, comprising:

sheet stacking means for supporting sheets;

a sheet supply roller having different radial dimensions along a periphery thereof for feeding out the sheets from said sheet stacking means;

separation means comprising a feed rotary member rotatable in a sheet feeding direction and a reverse rotary member rotatable in a direction opposite to the sheet feeding direction for separating the sheets fed out by said sheet supply roller one by one;

image forming means for forming an image on the sheet separated by said separation means;

driving means for generating a drive force to rotate said sheet supply roller and the rotary members of said separation means;

first rotation transmitting means for transmitting rotation force of said driving means to the reverse rotary member;

second rotation transmitting means for transmitting the rotation force of said driving means to said sheet-supply roller and to the feed rotary member; and

rotation controlling means provided in said second rotation transmitting means for interrupting transmission of the rotation drive force from said driving means to said sheet supply roller, after a predetermined amount of rotation of said sheet supply roller, to-thereby stop-rotation of said sheet supply roller and the feed rotary member.

11. A sheet supplying apparatus, comprising:

sheet supporting means for supporting sheets;

a sheet supply roller having different radial dimensions along a periphery thereof for feeding out the sheets from said sheet supporting means;

separation means, comprising a feed rotary member in a sheet feeding direction and a friction member, for separating the sheets fed out by said sheet supply roller;

driving means for generating a rotation drive force;

rotation transmitting means for transmitting the rotation drive force from said driving means to said sheet supply means and said feed rotary member, said sheet supply means and said feed rotary member being rotated by the rotation drive force transmitted by said rotation transmitting means; and

rotation controlling means for stopping the rotation of said sheet supply means and said feed rotary member, after predetermined amount of rotation of said sheet supply roller.

12. A sheet supplying apparatus according to claim 11, wherein said sheet supply roller having different radial dimensions along the periphery thereof is a semi-circular roller, and said rotation controlling means stops said sheet supply roller after one rotation thereof.

13. A sheet supply apparatus according to claim 11, further comprising convey means for conveying the sheet separated by said separation means, and said feed rotary member is stopped after a tip end of the separated sheet reaches to said convey means.

14. A sheet supplying apparatus according to claim 11, wherein said feed rotary member is connected to said second rotation transmitting means via a one-way clutch.

15. A sheet supplying apparatus according to claim 11, wherein said rotation controlling means is a spring clutch.

16. An image forming apparatus, comprising:

sheet supporting means for supporting sheets;

a sheet supply roller having different radial dimensions along a periphery thereof for feeding out the sheets from said sheet supporting means;

separation means, comprising a feed rotary member in a sheet feeding direction and a friction member, for separating the sheets fed out by said sheet supply roller;

image forming means for forming an image on the sheet separated by said separation means;

driving means for generating a rotation drive force;

rotation transmitting means for transmitting the rotation drive force from said driving means to said sheet supply means and said feed rotary member, said sheet supply means and said feed rotary member being rotated by said rotation drive force transmitted by said rotation transmitting means; and

rotation controlling means for stopping the rotation of said sheet supply means and said feed rotary member, after predetermined amount of rotation of said sheet supply roller.