CONVEYED OBJECT DETECTOR, CONVEYANCE DEVICE, DEVICE INCLUDING MOVABLE HEAD, CONVEYED OBJECT DETECTING METHOD, AND NON-TRANSITORY RECORDING MEDIUM STORING PROGRAM OF SAME

• US 20170355205A1
• Filed: 06/08/2017
• Published: 12/14/2017
• Est. Priority Date: 06/09/2016
• Status: Active Grant

• Current Assignee: Ricoh Company Limited
• Original Assignee: Ricoh Company Limited
• Inventors: Tobita, Katsuhiro, Kudo, Koichi
• Granted Patent: US 10,682,870 B2
• Time in Patent Office: Days
• CPC Class Codes: B41J 11/0095 Detecting means for copy material, e.g. for detecting or sensing presence of copy material or its leading or trailing end
• CPC Class Codes: G06T 2207/10016 Video; Image sequence
• CPC Class Codes: G06T 2207/10024 Color image
• CPC Class Codes: G06T 2207/30144 Printing quality
• CPC Class Codes: G06T 2207/30176 Document
• CPC Class Codes: G06T 7/0004 Industrial image inspection
• CPC Class Codes: G06T 7/246 using feature-based methods, e.g. the tracking of corners or segments
• CPC Class Codes: G06T 7/292 Multi-camera tracking

Abstract

A conveyed object detector includes first and second image obtaining units disposed at first and second positions different in a conveyance direction, to image a conveyed object to obtain first and second image data; respectively; a recognition unit to recognize an object adhering to the first and second image obtaining units based on imaging at the first and second positions to generate first and second stain data, respectively; a removal unit to remove the first and second stain data from the first and second image data, respectively; and a calculator to generate at least one of a position, a movement amount, and a moving speed of the conveyed object based on first and second corrected image data. Each of the first and second image obtaining units include a light source, an area sensor, and an optical element disposed between the area sensor and the conveyed object.

Claims

1. A conveyed object detector comprising:

a first image obtaining unit disposed at a first position to image a conveyed object to obtain first image data;

a second image obtaining unit disposed at a second position different from the first position in a conveyance direction of the conveyed object, the second image obtaining unit configured to image the conveyed object to obtain second image data,

each of the first image obtaining unit and the second image obtaining unit including;

a light source to irradiate the conveyed object with light;

an area sensor to receive reflected light reflected from the conveyed object; and

an optical element disposed between the area sensor and the conveyed object;

a recognition unit configured to;

recognize an object adhering to the first image obtaining unit based on imaging at the first position to generate first stain data; and

recognize an object adhering to the second image obtaining unit based imaging at the second position to generate second stain data;

a removal unit configured to;

remove the first stain data from the first image data, to generate first corrected image data; and

remove the second stain data from the second image data to generate second corrected image data; and

a calculator configured to generate, as a calculation result, at least one of a position, a movement amount, and a moving speed of the conveyed object based on the first corrected image data and the second corrected image data.

2. The conveyed object detector according to claim 1, wherein the first image obtaining unit and the second image obtaining unit are configured to image a pattern on the conveyed object, and

wherein the calculator is configured to generate the calculation result with reference to the pattern.

3. The conveyed object detector according to claim 2, wherein the pattern represents interference of the reflected light on a rugged shape of the conveyed object, and

the calculator is configured to generate the calculation result based on an image of the pattern.

4. The conveyed object detector according to claim 2, wherein the first image obtaining unit is configured to image the pattern at a first time point to obtain the first image data,

wherein the second image obtaining unit is configured to image the pattern at a second time point different from the first time point, to obtain the second image data, and

wherein the calculator is configured to calculate a position of the conveyed object in an orthogonal direction orthogonal to the conveyance direction, based on the first corrected image data and the second corrected image data.

5. The conveyed object detector according to claim 1, wherein the recognition unit is configured to:

superimpose a plurality of image data output by age obtaining unit to generate the first stain data; and

superimpose a plurality of image data output by the second image obtaining unit to generate the second stain data.

6. The conveyed object detector according to claim 1, wherein the removal unit is configured to remove the first stain data and the second stain data from each of the first image data and the second image data, to generate first corrected image data and the second corrected image data, respectively.

7. A conveyance device comprising:

a conveyor to convey the conveyed object; and

the conveyed object detector according to claim 1.

8. An apparatus comprising:

a head unit to move in an orthogonal direction orthogonal to the conveyance direction and perform an operation on the conveyed object;

the conveyance device according to claim 7; and

a head controller to control the head unit, based on the calculation result generated by the conveyed object detector.

9. The apparatus according to claim 8, further comprising:

a first support disposed upstream from the head unit in the conveyance direction; and

a second support disposed downstream from the head unit in the conveyance direction,

wherein one of the first image obtaining unit and the second image obtaining unit is disposed between the first support and the second support in the conveyance direction.

10. The apparatus according to claim 9, wherein the image obtaining unit is disposed between the head unit and the first support in the conveyance direction.

11. The apparatus according to claim 8, further comprising a head moving device to move the head unit in the orthogonal direction.

12. The apparatus according to claim 8, wherein the head controller is configured to determine a position of the head unit based on the calculation result generated by the conveyed object detector.

13. The apparatus according to claim 8, wherein the conveyed object is a continuous sheet.

14. The apparatus according to claim 8, wherein the head unit includes a liquid discharge head to perform, as the operation, image formation on the conveyed object.

15. A conveyed object detector comprising:

image obtaining means for imaging a conveyed object at a first position and a second position to obtain first image data and second image data, respectively, the second position different from the first position in a conveyance direction of the conveyed object;

recognition means for recognizing;

an adhering object based on imaging at the first position to generate first stain data; and

an adhering object based on imaging at the second position to generate second stain data;

removal means for removing the first stain data from the first image data to generate first corrected image data and removing the second stain data from the second image data to generate second corrected image data; and

calculating means for generating, as a calculation result, at least one of a position, a movement amount, and a moving speed of the conveyed object based on the first corrected image data and the second corrected image data.

16. A conveyed object detecting method comprising:

imaging, with a first area sensor and a second area sensor, a conveyed object at a first position and a second position to obtain first image data and second image data, respectively, the second position different from the first position in a conveyance direction of the conveyed object;

recognizing an adhering object adhering to the first area sensor based on imaging at the first position, to generate first stain data;

recognizing an adhering object adhering to the second area sensor based imaging at the second position, to generate second stain data;

removing the first stain data from the first image data, to generate first corrected image data;

removing the second stain data from the second image data, to generate second corrected image data; and

generating, as a calculation result, at least one of a position, a movement amount and a moving speed of the conveyed object based on the first corrected image data and the second corrected image data.

17. A computer-readable non-transitory recording medium storing a program for causing a computer to execute the method according to claim 16.