Image forming apparatus

• US 20050078973A1
• Filed: 08/26/2004
• Published: 04/14/2005
• Est. Priority Date: 08/26/2003
• Status: Active Grant

• Current Assignee: Ricoh Company Limited
• Original Assignee: Ricoh Company Limited
• Inventors: Suzuki, Nobutaka
• Granted Patent: US 7,274,886 B2
• Time in Patent Office: Days
• US Class Current: 399/45
• 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 2511/13 Thickness
• CPC Class Codes: B65H 2511/51 Presence
• CPC Class Codes: B65H 2515/60 Optical characteristics, e.g. colour, light
• CPC Class Codes: B65H 2553/412 in barrier arrangements, i.e. emitter facing a receptor element
• CPC Class Codes: B65H 2553/414 involving receptor receiving light reflected by a reflecting surface and emitted by a separate emitter
• CPC Class Codes: B65H 2553/44 Involving light guide, e.g. optical fibres
• CPC Class Codes: B65H 2557/61 for calibrating
• CPC Class Codes: B65H 7/14 by photoelectric feelers or detectors
• CPC Class Codes: G03G 15/5029 by measuring the copy material characteristics, e.g. weight, thickness
• CPC Class Codes: G03G 2215/00738 of sheet thickness or rigidity

Abstract

An image forming apparatus has a printer engine which forms an image on a medium; a unit which supplies the medium to the engine through a path; an element which emits light onto the medium at a position on the path; a receiving element which receives transmitted light of the light emitted which is transmitted through the medium; another receiving element which receives reflected light of the light emitted which is reflected by the medium; a unit which executes a detection through the emission and reception; a unit which determines a characteristic of the medium based on detection signals output by the receiving elements as a result of the detection; and a control unit which executes a control in the apparatus based on the characteristic.

Claims

1. An image forming apparatus comprising:

a printer engine configured to form an image on a medium;

a supply unit configured to supply the medium to the printer engine through a feed path;

a light emitting element configured to emit light onto the medium at a predetermined position on the feed path;

a transmitted light receiving element configured to receive transmitted light of the light emitted by the light emitting element which is transmitted through the medium;

a reflected light receiving element configured to receive reflected light of the light emitted by the light emitting element which is reflected by the medium;

a detecting unit which executes a detection through the emission of light and the reception of transmitted light and reflected light;

a first determining unit which determines a characteristic of the medium based on detection signals output by the transmitted light receiving element and the reflected light receiving element as a result of the detection; and

a control unit which executes a predetermined control in the image forming apparatus based on the characteristic determined by the first determining unit.

2. The image forming apparatus according to claim 1, wherein the first determining unit determines a thickness of the medium as the characteristic.

3. The image forming apparatus according to claim 1, further comprising:

a second determining unit configured to determine whether the medium is present based on one of the detection signals output by the transmitted light receiving element and the reflected light receiving element.

4. The image forming apparatus according to claim 1, wherein

the first determining unit is configured to determine a color of the medium as the characteristic based on the detection signal output by the reflected light receiving element.

5. The image forming apparatus according to claim 1, wherein

the detecting unit is configured to switch a quantity of the light emitted by the light emitting element between a plurality of quantities.

6. The image forming apparatus according to claim 5, wherein

the detecting unit is configured to execute the detection a plurality of times on the same medium by switching the quantity of the light.

7. The image forming apparatus according to claim 1, further comprising:

a correcting unit configured to correct an output of at least one of the light emitting element and the reflected light receiving element output as a result of the detection, based on an output of the transmitted light receiving element output when the light is emitted by the light emitting element while the medium is not present.

8. The image forming apparatus according to claim 1, further comprising:

a correcting unit configured to correct an output of at least one of the light emitting element and the transmitted light receiving element output as a result of the detection, based on an output of the reflected light receiving element output when the light is emitted by the light emitting element while the medium is not present.

9. The image forming apparatus according to claim 1, further comprising:

a light guide member configured to guide the light emitted by the light emitting element when the medium is not present to the reflected light receiving element.

10. The image forming apparatus according to claim 3, wherein

the control unit is configured to control an image forming operation of the image forming apparatus as the predetermined control.

11. The image forming apparatus according to claim 1, wherein

the control unit is configured to notify a user of information related to the characteristic as the predetermined control.

12. The image forming apparatus according to claim 1, further comprising:

a scanner configured to read the image from an original, wherein

the printer engine is configured to form the image based on the image read by the scanner.