Sheet discriminator and image forming apparatus incorporating the sheet discriminator

Patent metadata

Field	Value
Publication number	US-9890003-B2
Application number	US-201514868915-A
Country	US
Kind code	B2
Filing date	Sep 29, 2015
Priority date	Sep 30, 2014
Publication date	Feb 13, 2018
Grant date	Feb 13, 2018

Abstract

A sheet discriminator, which can be included in an image forming apparatus, includes a sheet loader on which a recording medium is loaded, an information detector including a light emitter to emit light to a surface of the recording medium loaded on the sheet loader and a light receiver to receive the light emitted by the light emitter and detecting information of the recording medium, a sheet distinguisher to distinguish a type of the recording medium based on the information detected by the information detector, and a detector body encasing at least the information detector therein and having an opening formed on an opposing face facing the sheet loader. The opposing face has an opening formed thereon. The opening has at least one arc-shaped side.

First claim

What is claimed is:

1. A sheet discriminator comprising:
a sheet loader, downstream from a sheet insertion opening, on which a recording medium is loaded;
an information detector including a light emitter to emit light to a surface of the recording medium loaded on the sheet loader and a light receiver to receive the light emitted by the light emitter and detecting information of the recording medium;
a sheet distinguisher to distinguish a type of the recording medium based on the information detected by the information detector;
a detector body encasing at least the information detector therein and having an opening downstream from the sheet insertion opening in the sheet insertion direction and formed on an opposing face facing the sheet loader, the opposing face being parallel to the sheet insertion direction, the opening having at least one arc-shaped side;
a sheet thickness detector including a displacement gauge to sandwich the recording medium with an opposing member disposed facing the displacement gauge and to move from an initial position at which the displacement gauge stays when no recording medium is sandwiched with the opposing member and a displacement detector to detect an amount of displacement of the displacement gauge and detecting a thickness of the recording medium based on detection results obtained by the displacement detector; and
a pressing member to press the recording medium to a measurement datum plane mounted on the opposing member when the sheet thickness detector detects the sheet thickness of the recording medium,
wherein the displacement detector contacts the measurement datum plane at the initial position,
wherein the opposing member has an opposing part facing an end of the recording medium,
wherein the opposing part is recessed to be lower than the measurement datum plane when the recording medium is located at an information detecting position to detect information of the recording medium by the information detector.

2. The sheet discriminator according to claim 1 , further comprising a sheet thickness calibrator to calibrate a detected thickness of the recording medium detected by the sheet thickness detector with a reference calibration value.

3. The sheet discriminator according to claim 1 , wherein the light emitter emits laser light.

4. The sheet discriminator according to claim 1 ,
wherein the light receiver of the information detector includes multiple light receivers,
wherein the multiple light receivers include a transmission light receiver to receive transmitted light emitted from the light emitter and transmitted through the recording medium.

5. The sheet discriminator according to claim 1 ,
wherein the light receiver of the information detector includes multiple light receivers,
wherein the multiple light receivers include a specular reflection light receiver to receive specular reflection light emitted from the light emitter and reflected on the recording medium and a diffused reflection light receiver to receive diffused reflection light emitted from the light emitter and reflected on the recording medium.

6. The sheet discriminator according to claim 1 , further comprising a communicator to communicate the sheet discriminator and an image forming apparatus.

7. A sheet discriminator comprising:
a sheet loader, downstream from a sheet insertion opening, on which a recording medium is loaded;
an information detector including a light emitter to emit light to a surface of the recording medium loaded on the sheet loader and a light receiver to receive the light emitted by the light emitter and detecting information of the recording medium;
a sheet distinguisher to distinguish a type of the recording medium based on the information detected by the information detector;
a detector body encasing at least the information detector therein and having an opening downstream from the sheet insertion opening in the sheet insertion direction and formed on an opposing face facing the sheet loader, the opposing face being parallel to the sheet insertion direction, the opening having at least one arc-shaped side;
a sheet thickness detector including a displacement gauge to sandwich the recording medium with an opposing member disposed facing the displacement gauge and to move from an initial position at which the displacement gauge stays when no recording medium is sandwiched with the opposing member and a displacement detector to detect an amount of displacement of the displacement gauge and detecting a thickness of the recording medium based on detection results obtained by the displacement detector; and
a sheet thickness calibrator configured to calibrate a measured thickness of the recording medium detected by the sheet thickness detector with a reference calibration value.

8. The sheet discriminator according to claim 7 , further comprising a calibration value changer to change the calibration value.

9. The sheet discriminator according to claim 7 , further comprising a calibration value memory to store the calibration value.

10. The sheet discriminator according to claim 7 , wherein the sheet thickness calibrator calibrates the detected thickness of the recording medium when the detected thickness of the recording medium is 300 μm or greater.

11. The sheet discriminator according to claim 7 , wherein the calibration value is determined based on a difference between the detected thickness detected by the sheet thickness detector and an actual thickness of the recording medium.

12. A sheet discriminator comprising:
a sheet loader on which a recording medium is loaded;
an information detector including a light emitter to emit light to a surface of the recording medium loaded on the sheet loader and a light receiver to receive the light emitted by the light emitter and detecting information of the recording medium;
a sheet distinguisher to distinguish a type of the recording medium based on the information detected by the information detector; and
a detector body including the information detector therein and having an opening formed on an opposing face facing the sheet loader,
a length in a sheet conveying direction of an upper part of the opening being smaller than a length in the sheet conveying direction of a lower part of the opening, wherein the information detector detects reflection light to the recording medium by multiple sensors disposed at different angles to the recording medium, and
wherein the information detector receives diffused reflection light to the recording medium by multiple diffused reflection light receiving sensors of the multiple sensors disposed at different angles to the recording medium.

13. The sheet discriminator according to claim 12 , wherein the opening has at least one arc-shaped side.

14. The sheet discriminator according to claim 12 , wherein the opening has at least one chamfered side.

15. An image forming apparatus comprising:
an apparatus body;
the sheet discriminator according to claim 1 disposed outside the apparatus body; and
an image forming part to form an image on the recording medium discriminated by the sheet discriminator.

16. The image forming apparatus according to claim 15 , further comprising
a light emission controller to control activation and stop of the light emitter; and
an instruction device disposed on the apparatus body and transmitting an instruction to the light emission controller.

Assignees

• Nakayama Satoshi
• Takenaga Noriaki
• Makino Hideyo
• Ofuchi Tetsuya
• Nishimura Takayuki
• Sekino Yasuyuki
• Matsumoto Tohru
• Kobayashi Yukifumi
• Ricoh Co Ltd

Inventors

• Nakayama Satoshi
• Takenaga Noriaki
• Makino Hideyo
• Ofuchi Tetsuya
• Nishimura Takayuki
• Sekino Yasuyuki
• Matsumoto Tohru
• Kobayashi Yukifumi

Classifications

• B65H7/06

  responsive to presence of faulty articles or incorrect separation or feed (B65H7/14 takes precedence) · CPC title

• B65H2511/416

  of material · CPC title

• G03G15/5029

  by measuring the copy material characteristics, e.g. weight, thickness · CPC title

• B65H2553/412

  in barrier arrangements, i.e. emitter facing a receptor element · CPC title

• B65H2553/414

  involving receptor receiving light reflected by a reflecting surface and emitted by a separate emitter · CPC title