Printing media feeding apparatus, printing apparatus provided with the feeding apparatus, printing media feeding speed control method and computer program

• US 8,376,640 B2
• Filed: 08/12/2005
• Issued: 02/19/2013
• Est. Priority Date: 08/23/2004
• Status: Expired due to Fees

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Ogawa, Kaoru
• Primary Examiner(s): Colilla, Daniel J
• Assistant Examiner(s): FERGUSON SAMRETH, MARISSA LIANA
• Application Number:
  US11/203,395
• Publication Number:
  US 20060039736A1
• Time in Patent Office: 2,748 Days
• Field of Search: 400/582, 400/615.2, 400/279, 400/229, 400/61, 400/578, 358/1.9, 347/172, 347/16, 347/211, 347/14
• US Class Current: 400/582
• CPC Class Codes: B41J 11/42 Controlling printing material conveyance for accurate alignment of the printing material with the printhead; Print registering
• CPC Class Codes: B41J 13/103 for the sheet feeding section
• CPC Class Codes: G03G 15/6529 Transporting G03G15/6555 takes precedence
• CPC Class Codes: G03G 2215/00645 Speedometer
• CPC Class Codes: G03G 2215/00746 of sheet velocity

Abstract

The present invention prevents density irregularity from appearing in a print result and to thereby improve image quality by controlling a motor so that the rotational speed of a drive shaft that feeds printing media is constant. The present invention provides a printing media feeding apparatus including a feeding section that includes a motor, a drive transmission mechanism which transmits a driving force of the motor, and a drive shaft to which the driving force is transmitted by the drive transmission mechanism. The drive shaft is rotated to feed the printing medium. A detection section is provided having at least a portion secured to the drive shaft and the detection section determines the rotational speed of the drive shaft and a controller controls the motor based on an input from the detection section so that the rotational speed the of the drive shaft is constant.

Claims

1. A printing media feeding apparatus comprising:

feeding means that includes a motor, a drive transmission mechanism which transmits a driving force of the motor, and a drive shaft to which the driving force is transmitted by the drive transmission mechanism, the drive shaft being rotated to feed or transport a printing media;

detection means that has a portion which is mechanically connected to the drive shaft and detects the rotational speed of the drive shaft, wherein the detection means generates a plurality of pulse signals while the drive shaft is rotated in a feed direction and at least two of the pulse signals corresponding to rotation of the drive shaft in the feed direction while one line of image information is being printed, the pulse signals providing an indication of rotational speed; and

control means for controlling the motor, the control means controlling the motor based on an input from the detection means so that the rotational speed of the drive shaft becomes substantially constant, and as a result, the speed of the printing media being fed by the feeding means also becomes substantially constant, wherein the control means further includes a moving-average circuit that directly receives an output of a Kalman filter and a comparing control circuit receives an output from the moving-average circuit, the comparing control circuit compares the output from the moving-average circuit with reference data stored in a memory and provides a control output for controlling the motor based on a comparison result, and further wherein the comparing control circuit determines a rotational speed fluctuation component and controls the stepping motor to substantially eliminate or reduce the rotational speed fluctuation component.

2. The printing media feeding apparatus according to claim 1, wherein the drive shaft is a capstan.

3. A printing apparatus comprising:

a print head that prints visual data on the printing media;

feeding means that includes a motor, a drive transmission mechanism which transmits a driving force of the motor, and a drive shaft to which the driving force is transmitted by the drive transmission mechanism, the drive shaft being rotated to feed or transport a printing media;

detection means that has a portion which is mechanically connected to the drive shaft and detects the rotational speed of the drive shaft, wherein the detection means generates a plurality of pulse signals while the drive shaft is rotated in a feed direction and at least two of the pulse signals corresponding to rotation of the drive shaft in the feed direction while one line of image information is being printed, the pulse signals providing an indication of rotational speed; and

control means for controlling the motor, the control means controlling the motor based on an input from the detection means so that the rotational speed of the drive shaft becomes substantially constant, and as a result, the speed of the printing media being fed by the feeding means also because substantially constant, wherein the control means further includes a moving-average circuit that directly receives an output of a Kalman filter and a comparing control circuit receives an output from the moving-average circuit, the comparing control circuit compares the output from the moving-average circuit with reference data stored in a memory and provides a control output for controlling the motor based on a comparison result, and further wherein the comparing control circuit determines a rotational speed fluctuation component and controls the stepping motor to substantially eliminate or reduce the rotational speed fluctuation component.

4. A printing media feeding speed control method that rotates a drive shaft through a drive transmission mechanism transmitting a driving force of a motor to feed printing media, comprising:

detecting the rotational speed of the drive shaft via a detection mechanism having at least a portion of which attached to the drive shaft, wherein the detection mechanism generates a plurality of pulse signals while the drive shaft is rotated in a feed direction and at least two of the pulse signals corresponding to rotation of the drive shaft in the feed direction while one line of image information is being printed, the pulse signals providing an indication of rotational speed; and

controlling the rotation number of the motor based on the detected rotational speed so that the rotational speed of the drive shaft becomes substantially constant, and as a result, the speed of the printing media being driven by the drive shaft also becomes substantially constant, wherein the control means further includes a moving-average circuit that directly receives an output of a Kalman filter and a comparing control circuit receives an output from the moving-average circuit, the comparing control circuit compares the output from the moving-average circuit with reference data stored in a memory and provides a control output for controlling the motor based on a comparison result, and further wherein the comparing control circuit determines a rotational speed fluctuation component and controls the stepping motor to substantially eliminate or reduce the rotational speed fluctuation component.

5. The printing media feeding speed control method according to claim 4, further comprising a step of performing moving-average processing directly or indirectly on an output of a Kalman filter.

6. The printing media feeding speed control method according to claim 4, wherein said drive shaft is positioned so as to directly contact the printing media during feeding and to cause the printing media to move.

7. A non-transitory computer readable medium containing a computer program used for a printing media feeding speed control, the computer program when running controlling rotation of a drive shaft through a drive transmission mechanism transmitting a driving force of a motor to feed printing paper, the computer program controlling:

a memory, wherein the memory is an electronic or magnetic memory;

detecting the rotational speed of the drive shaft via a detection mechanism having at least a portion of which attached to the drive shaft, wherein the detection mechanism generates a plurality of pulse signals while the drive shaft is rotated in a feed direction and at least two of the pulse signals corresponding to rotation of the drive shaft in the feed direction while one line of image information is being printed, the pulse signals providing an indication of rotational speed; and

controlling the rotation of the motor based on the detected rotational speed so that the rotational speed of the drive shaft becomes substantially constant, and as a result, the speed of the printing media being driven by the drive shaft also becomes substantially constant, wherein the computer program further includes a control means including a moving-average circuit that directly receives an output of a Kalman filter and a comparing control circuit receives an output from the moving-average circuit, the comparing control circuit compares the output from the moving-average circuit with reference data stored in the memory and provides a control output for controlling the motor based on a comparison result and further wherein the comparing control circuit determines a rotational speed fluctuation component and controls the motor to substantially eliminate or reduce the rotational speed fluctuation component.

8. A printing media feeding apparatus comprising:

a feeding section that includes a motor, a drive transmission mechanism which transmits a driving force of the motor, and a drive shaft to which the driving force is transmitted by the drive transmission mechanism, the drive shaft being rotated to feed or transport a printing media;

a detection section that has a portion which is mechanically connected to the drive shaft and detects the rotational speed of the drive shaft, wherein the detection section generates a plurality of pulse signals while the drive shaft is rotated in a feed direction and at least two of the pulse signals corresponding to rotation of the drive shaft in the feed direction while one line of image information is being printed, the pulse signals providing an indication of rotational speed; and

a controller that controls the motor, the controller controlling the motor based on an input from the detection section so that the rotational speed of the drive shaft becomes substantially constant, and as a result, the speed of the printing media being fed by the feeding means also becomes substantially constant,

wherein said controlling step includes the step of applying a signal from the detection mechanism in said detecting step to a Kalman filter that extracts a rotational speed fluctuation component of the drive shaft, wherein the control means further includes a moving-average circuit that directly receives an output of a Kalman filter and a comparing control circuit receives an output from the moving-average circuit, the comparing control circuit compares the output from the moving-average circuit with reference data stored in a memory and provides a control output for controlling the motor based on a comparison result, and further wherein the comparing control circuit determines a rotational speed fluctuation component and controls the stepping motor to substantially eliminate or reduce the rotational speed fluctuation component.

9. The printing media feeding apparatus according to claim 8, wherein said drive shaft is positioned so as to directly contact the printing media during feeding and to cause the printing media to move.

10. The printing media feeding apparatus according to claim 8, wherein said drive shaft is a platen roller.

11. A printing apparatus comprising:

a print head that prints visual data on a printing media;

a feeding section that includes a motor, a drive transmission mechanism which transmits a driving force of the motor, and a drive shaft to which the driving force is transmitted by the drive transmission mechanism, the drive shaft being rotated to feed or transport the printing media;

a detection section has a portion which is mechanically connected to the drive shaft and detects the rotational speed of the drive shaft, wherein the detection section generates a plurality of pulse signals while the drive shaft is rotated in a feed direction and at least two of the pulse signals corresponding to rotation of the drive shaft in the feed direction while one line of image information is being printed, the pulse signals providing an indication of rotational speed; and

a controller that controls the motor, the controller controlling the motor based on an input from the detection section so that the rotational speed of the drive shaft becomes substantially constant, and as a result, the speed of the printing media being fed by the feeding means also because substantially constant, wherein the control means further includes a moving-average circuit that directly receives an output of a Kalman filter and a comparing control circuit receives an output from the moving-average circuit, the comparing control circuit compares the output from the moving-average circuit with reference data stored in a memory and provides a control output for controlling the motor based on a comparison result, and further wherein the comparing control circuit determines a rotational speed fluctuation component and controls the stepping motor to substantially eliminate or reduce the rotational speed fluctuation component.

12. The printing apparatus according to claim 11, wherein said drive shaft is positioned so as to directly contact the printing media during feeding and to cause the printing media to move.

13. The printing apparatus according to claim 11, wherein said drive shaft is a platen roller.