Image formation apparatus with printer engine control which judges whether recording sheets can be fed

• US 6,496,660 B2
• Filed: 05/21/2001
• Issued: 12/17/2002
• Est. Priority Date: 05/22/2000
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Takahashi, Atsuya, Sato, Kaoru, Tachibana, Tatsuto, Serizawa, Yoji
• Primary Examiner(s): Braun, Fred L
• Application Number:
  US09/860,462
• Publication Number:
  US 20020009301A1
• Time in Patent Office: 575 Days
• Field of Search: 399/16, 399/23, 399/371, 399/381, 399/388, 399/391, 358/300, 271/9.01, 271/9.13
• US Class Current: 399/16
• CPC Class Codes: G03G 15/6529 Transporting G03G15/6555 takes precedence
• CPC Class Codes: G06K 15/16 Means for paper feeding or form feeding

Abstract

An engine control unit and corresponding method of controlling the engine in which the engine control unit receives a print reservation command for plural pages prior to a print request command from a printer control unit. When the engine control unit received the print reservation command for the plural pages, it is judged whether or not a sheet feed operation of recording sheets can be performed. When it is judged that the recording sheets can be fed, the recording sheets are fed and transported to a predetermined position on a transportation path with a minimum constant interval corresponding to the sheet size by sheet feed rollers or transportation rollers, then printing operation is performed according to the print request command.

Claims

1. An image formation apparatus of an electrophotographic system, comprising:

sheet feed means for feeding recording sheets one by one;

transportation means for transporting the recording sheets fed by said sheet feed means to a position where a visualized image formed on a photosensitive drum is transferred to the recording sheet, through a transportation path;

an engine control unit for controlling drives of said sheet feed means and said transportation means; and

a printer control unit for developing image data and transmitting a print request command to said engine control unit,

wherein said engine control unit has judgment means for judging whether or not the recording sheets can be fed when a print reservation command for plural pages of the sheets was received from said printer control unit prior to the print request command, and the drives of said sheet feed means and said transportation means are controlled to transport the recording sheets to a predetermined position on the transportation path when said judgment means judges that the recording sheets can be fed.

2. An apparatus according to claim 1, wherein a serial communication is performed between said engine control unit and said printer control unit.

3. An apparatus according to claim 1, wherein when it is designated that the recording sheets are fed from plural sheet feed ports according to the print reservation command for plural pages, the drives of said sheet feed means and said transportation means are controlled to transport the recording sheets from the plural sheet feed ports to the lowest-stream position capable of performing printing in order of a print reservation for the plural pages prior to the print request command.

4. An apparatus according to claim 1, wherein when it is designated that the recording sheets fed from plural sheet feed ports according to the print reservation command for the plural pages, the drives of said sheet feed means and said transportation means are controlled to transport the recording sheets from the plural sheet feed ports to a stream position more upper than a junction of the most-upper-stream on the transportation path in case of feeding the sheets from the plural sheet feed ports prior to the print request command.

5. An apparatus according to claim 1, wherein when it is designated that the recording sheets are fed from plural sheet feed ports according to the print reservation command for the plural pages, there is set a mode for controlling the drives of said sheet feed means and said transportation means to transport the recording sheets from the plural sheet feed ports to the lowest-stream position capable of performing printing in order of the print reservation for the plural pages prior to the print request command, a mode for controlling the drives of said sheet feed means and said transportation means to transport the recording sheets from the plural feed ports to a stream position more upper than a junction of the most-upper-stream on the transportation path in a case where the sheets were fed from the plural sheet feed ports to the print request command, and selection means for selecting one of the both modes.

6. An image formation apparatus of an electrophotographic system, comprising:

sheet feed means for feeding recording sheets one by one;

transportation means for transporting the recording sheets fed by said sheet feed means to a transference means for transferring a visualized image formed on a photosensitive drum to the recording sheet, through a transportation path;

an engine control unit for controlling drives of said sheet feed means and said transportation means; and

a printer control unit for developing image data and transmitting a print command for issuing a print instruction and a print reservation command for previously instructing print information such as a sheet feed port, sheet size or the like prior to the print command, to the engine control unit through a serial communication line,

wherein said engine control unit has judgment means for judging whether or not a sheet feed operation of the recording sheets can be performed when the print reservation command for plural pages was received from said printer control unit, and when said judgment means judged that the recording sheets can be fed, drives of said sheet feed means and said transportation means are controlled to transport the recording sheets to a predetermined position on the transportation path.

7. An apparatus according to claim 6, wherein plural sheet feed means are equipped, and said transportation means can be driven or stopped in driving of said transference means,

wherein the predetermined position on the transportation path is more upstream than that of said transference means, and a leading edge of the recording sheet is on a more downstream position from where the sheet is not transported to said transference means when said transportation means is stopped,

wherein the drives of said sheet feed means and said transportation means are controlled to feed and transport the recording sheets to the predetermined position on the transportation path in order of reception of the print reservation command, when said engine control unit receives the print reservation command for plural pages to be fed from said plural sheet feed means from said print control unit.

8. An apparatus according to claim 6, wherein plural sheet feed means are equipped, and each of said sheet feed means can be driven or stopped in driving of said transportation means,

wherein the predetermined position on the transportation path is more upper than that of a junction where a transportation path of another sheet feed means is interflowed, and a leading edge of the recording sheet is on the lowest-stream position from where the sheet is not transported to the junction when said sheet feed means is stopped,

wherein the drives of said sheet feed means and said transportation means are controlled to feed and transport the recording sheets to the predetermined position on the transportation path from all of said sheet feed means reserved in the print reservation command, when said engine control unit receives the print reservation command for plural pages to be fed from said plural sheet feed means from said print control unit.

9. An apparatus according to claim 6, wherein when said engine control unit received the print reservation command for the plural pages to be fed from said sheet feed means from said print control unit, there equipped selection means which can select one of control means from first control means for controlling the drives of said sheet feed means and said transportation means to feed and transport the recording sheets to the predetermined position on the transportation path in order of reception of the print reservation command and second control means for controlling the drives of said sheet feed means and said transportation means to feed and transport the recording sheets to the predetermined position on the transportation path from all of said sheet feed means reserved in the print reservation command.

10. A control method of an image formation apparatus of an electrophotographic system, comprising:

a sheet feed step of feeding recording sheets one by one from sheet feed means;

a transportation step of transporting the recording sheets fed by said sheet feed means to a transference means for transferring a visualized image formed on a photosensitive drum to the recording sheet, through a transportation path;

an engine control step of controlling drives of said sheet feed step and said transportation step by an engine control unit; and

a printer control step of developing image data and transmitting a print command for issuing a print instruction and a print reservation command for previously instructing print information such as a sheet feed port, sheet size or the like prior to the print command, to the engine control unit through a serial communication line by a printer control unit,

wherein the engine control unit judges whether or not a sheet feed operation of the recording sheets can be performed when the print reservation command for plural pages is received from the printer control unit, and when it is judged that the recording sheets can be fed, drives of said sheet feed means and said transportation means are controlled to transport the recording sheets to a predetermined position on the transportation path.

11. An image formation apparatus comprising:

image formation means for forming images on recording sheets;

sheet feed means for feeding the recording sheets;

transportation means for transporting the recording sheets fed by said sheet feed means to said image formation means through a transportation path;

an engine control unit for controlling drives of said sheet feed means and said transportation means; and

reception means for receiving a print request command transmitted from a printer control unit and a reservation command used in reserving printing prior to the print request command,

wherein said engine control unit has judgment means for judging whether or not the recording sheets for pages corresponding to print reservation can be fed, and the plural recording sheets can be fed before receiving the print request command in accordance with a judgment of said judgment means in a case where the print reservation for plural pages is made by using the reservation command.

12. An apparatus according to claim 11, wherein plural sheet feed means are provided, and at least one of said sheet feed means and sheet size can be designated for every recording sheet of each page corresponding to the print reservation from the printer control unit.

13. An apparatus according to claim 12, wherein when the print reservation for plural pages to use said plural sheet feed means is made, printing is performed in order of the made print reservation.

14. An apparatus according to claim 13, wherein the recording sheets are fed every page corresponding to the print reservation at timing of corresponding to information related to the recording sheets of pages previously print reserved.

15. An apparatus according to claim 12, wherein when the print reservation for the plural pages to use said plural sheet feed means is made, printing can be performed in an arbitrary order for the print reserved plural pages.

16. An apparatus according to claim 15, wherein when the print reservation for the plural pages to use said plural sheet feed means is made, said engine control unit controls drives to feed and transport the recording sheets by the sheet feed means to an upstream position at a junction, where a transportation path from said sheet feed means joins a transportation path from another sheet feed means.

17. An apparatus according to claim 12, wherein when the print reservation for the plural pages to use said plural sheet feed means is made, selection means selects one of a first mode for performing printing in order of the made print reservation and a second mode for performing printing in an arbitrary order for the print reserved plural pages.

18. An apparatus according to claim 11, further comprising said printer control unit.

19. An apparatus according to claim 18, wherein said printer control unit has means for developing image code data transmitted from an external equipment to bit data necessary for an image formation.

20. An apparatus according to claim 11, wherein said image formation means has means for forming an image on an image support body using an electrophotographic method and transference means for transferring the image formed on the image support body to the recording sheet.