Paper feeding device, image forming apparatus and paper feeding method

Patent metadata

Field	Value
Publication number	US-10124974-B1
Application number	US-201715592770-A
Country	US
Kind code	B1
Filing date	May 11, 2017
Priority date	May 11, 2017
Publication date	Nov 13, 2018
Grant date	Nov 13, 2018

Abstract

A paper feeding device according to an embodiment includes a paper feeding cassette that holds a plurality of sheets and has a stacking surface with an angle A relative to horizontal that changes depending on a quantity of sheets stacked thereon. A pickup roller feeds the plurality of sheets from the paper feeding cassette. A separation roller separates the plurality of sheets from each other in a case where the plurality of sheets are fed from the paper feeding cassette in an overlapped state. A guide unit has a guide surface which is inclined upwards on a downstream side thereof in the transport direction of the plurality of sheets. A drive unit changed an angle B of the guide surface relative to horizontal. A control device controls the drive unit to change the angle B based on the angle A.

First claim

What is claimed is:

1. A paper feeding device comprising:
a paper feeding cassette that holds a plurality of sheets and has a stacking surface with an angle A relative to horizontal that changes depending on a quantity of sheets stacked thereon;
a pickup roller that feeds the plurality of sheets from the paper feeding cassette;
at least one separation roller arranged downstream from the paper feeding cassette in a transport direction of the plurality of sheets and configured to separate the plurality of sheets from each other in a case where the plurality of sheets are fed from the paper feeding cassette in an overlapped state;
a guide unit arranged between the paper feeding cassette and the at least one separation roller, the guide unit having a guide surface which is inclined upwards on a downstream side thereof in the transport direction of the plurality of sheets;
a drive unit configured to set an angle B of the guide surface relative to horizontal to be one of a first predetermined inclination angle and a second predetermined inclination angle larger than the first predetermined inclination angle; and
a control device that controls the drive unit to change the angle B;
a stacking surface angle detecting sensor that detects the angle A and outputs the detected angle A to the control device, wherein
the control device controls the drive unit, based on the output from the stacking surface angle detecting sensor, such that angle B is the first predetermined inclination angle when angle A is smaller than a predetermined angle threshold, and angle B is the second predetermined inclination angle when angle A is larger than the predetermined angle threshold.

2. A paper feeding device comprising:
a paper feeding cassette that holds a plurality of sheets and has a stacking surface with an angle A relative to horizontal that changes depending on a quantity of sheets stacked thereon;
a pickup roller that feeds the plurality of sheets from the paper feeding cassette;
a pair of separation rollers arranged downstream from the paper feeding cassette in a transport direction of the plurality of sheets and configured to separate a plurality of sheets from each other in a case where the plurality of sheets are fed from the paper feeding cassette in an overlapped state;
a guide unit arranged between the paper feeding cassette and the separation rollers, the guide unit having a guide surface which is inclined upwards on a downstream side thereof in the transport direction of the plurality of sheets at an angle B relative to horizontal, wherein angle B is one of a first predetermined inclination angle and a second predetermined inclination angle larger than the first predetermined inclination angle;
a stacking surface angle detecting sensor that detects the angle A and outputs the detected angle A to the control device and
a guide surface angle adjusting mechanism that changes angle B in accordance with the detected angle A such that angle B is the first predetermined inclination angle when angle A is smaller than a predetermined angle threshold, and angle B is the second predetermined inclination angle when angle A is larger than the predetermined angle threshold.

3. The paper feeding device according to claim 2 , wherein the guide surface angle adjusting mechanism includes an arm that rotates in accordance with the change of angle A, and a rotary movement force transmitting mechanism that transmits a rotary movement force of the arm to the guide unit.

4. The paper feeding device according to claim 3 , wherein the rotary movement force transmitting mechanism includes at least one rotary body which when driven rotates the arm, and rotation of the rotary body changes the angle B.

5. A paper feeding method comprising the steps of:
feeding at least one sheet from a paper feeding cassette having a stacking surface with an angle A relative to horizontal that changes depending on a quantity of sheets stacked thereon;
guiding the at least one sheet along a guide surface positioned downstream of the paper feeding cassette and upstream of a separation unit in a transport direction of the at least one sheet;
separating a plurality of sheets from each other with the separation unit, in a case where the plurality of sheets are fed from the paper feeding cassette in an overlapped state;
detecting the angle A; and
changing an angle B of the guide surface relative to horizontal in accordance with the detected angle A such that angle B is a first predetermined inclination angle when angle A is smaller than a predetermined angle threshold, and angle B is a second predetermined inclination angle larger than the first predetermined inclination angle when angle A is larger than the predetermined angle threshold.

6. The paper feeding method according to claim 5 , wherein angle B is changed by a drive unit controlled by a control device.

7. The paper feeding method according to claim 5 , wherein angle B is mechanically changed in accordance with the change of angle A via a motion transmitting mechanism.

Assignees

• Toshiba Kk
• Toshiba Tec Kk

Inventors

• Kurita Eizo

Classifications

• B65H2511/214

  Inclination · CPC title

• B65H3/56

  Elements, e.g. scrapers, fingers, needles, brushes, acting on separated article or on edge of the pile {(B65H3/52 takes precedence)} · CPC title

• B65H2515/10

  Mass, e.g. mass flow rate; Weight; Inertia · CPC title

• B65H7/02

  by feelers or detectors · CPC title

• B65H5/36

  Article guides or smoothers, e.g. movable in operation · CPC title