JP2008213187A - Printer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To shorten a waiting time of first printing while preventing increase of conveyance sound and disorder of papers. <P>SOLUTION: A plurality of optional feeders 12a-12d are set to a printer body 11. When printing is performed, conveyance of the paper is carried out by using a high-speed conveyance speed in printing of the first sheet, and the papers are conveyed by only a synchronizing conveyance speed in printing of the second sheet and after that. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a printing apparatus.

  A tandem type printing apparatus has a plurality of OPC (Organic Photo Conductor) drums corresponding to each color arranged side by side, forms a single color toner image on each drum, and transfers these single color toner images to an intermediate transfer belt. To a printing apparatus for secondary transfer onto a sheet. The tandem type printing apparatus has an advantage that the image forming time is shortened because the toner images of the respective colors are simultaneously formed using a plurality of OPC drums corresponding to the respective colors.

  In such a tandem type printing apparatus, the timing at which an image is formed on the intermediate transfer belt and the timing at which the paper is conveyed to the position of the intermediate transfer belt are synchronized, and the image formed on the intermediate transfer belt is It is necessary to control so that it is transferred to a predetermined position. Regarding the control of the sheet conveyance timing, for example, in Patent Document 1, the time when the sheet passes through a predetermined position is detected, and the deviation from the target time generated at the time of sheet feeding is calculated from the detection result. There has been proposed one that is controlled so as to adjust the conveyance speed.

  In addition, in a printing apparatus typified by a printer apparatus, a copier apparatus, a facsimile apparatus, etc. that are already widely used, a plurality of option feeders are arranged in multiple stages in the vertical direction as an optional apparatus for feeding paper to the main body apparatus. There is something.

In the case of an optional feeder arranged in multiple stages in the vertical direction, the sheet transport time varies depending on the position of the optional feeder with respect to the main unit. That is, as the option feeder mounted away from the main body apparatus, the sheet conveyance distance becomes longer, and the sheet conveyance time becomes longer. For this reason, conventionally, in addition to the synchronous conveyance speed for supplying paper to the intermediate transfer belt at a predetermined timing, a high-speed conveyance speed for conveying the paper at a conveyance speed faster than the synchronous conveyance speed can be set. Yes. By combining the synchronous conveyance speed and the high-speed conveyance speed, the sheet is supplied to the intermediate transfer belt at a predetermined timing and the sheet conveyance time is shortened.
JP-A-5-85644

  However, when combining the synchronous transport speed and the high speed transport speed, it is necessary to switch the paper transport speed. In particular, when a plurality of sheets are continuously conveyed, the control of switching the conveyance speed is complicated, and it is necessary to set the timing for changing the speed with high accuracy.

  In order to set the timing of speed change with high accuracy, it is necessary to increase the communication speed between the main unit and the option feeder and shorten the communication delay time. For this reason, it is necessary to provide expensive communication processing, which in turn increases the cost of the printing device itself. In addition, if the speed change timing is disturbed, problems such as noise caused by “pulling” between a certain page and the previous page, and so-called “Z-folding” due to the pushing of the paper occur.

  SUMMARY OF THE INVENTION In view of the above-described problems, an object of the present invention is to suppress problems and cost increases caused by changing the paper conveyance speed in a printing apparatus and to improve the printing speed.

  In order to solve the above-described problems, a printing apparatus according to the present invention is a printing apparatus including a main body device that prints on paper based on an image signal and an optional device that supplies the paper to the main body device. And a transport means for transporting the paper in the optional device, and a control means capable of setting the transport speed of the paper in the transport means to a synchronous transport speed and a high speed transport speed, the control means from the optional device When printing with the paper transported to the main unit, it is determined whether it is the first print, and the paper transport speed is set to the high transport speed only when it is determined that it is the first print. Characterized by enabling

  Further, in the printing apparatus of the present invention, when a plurality of the optional devices are installed, the control means determines the first sheet according to the positional relationship between the main device and the selected optional device. A configuration is adopted in which the paper conveyance speed in printing is set.

  In the printing apparatus of the present invention, the control unit adopts a configuration in which the sheet is conveyed by combining the high-speed conveyance speed and the synchronous conveyance speed when it is determined that the printing is the first sheet. To do.

  In the printing apparatus of the present invention, the control unit employs a configuration in which it is determined that the printing is the first sheet when a predetermined time has elapsed since the previous printing in the main body apparatus.

According to the present invention, a sheet can be conveyed at a high conveyance speed by printing the first sheet. For this reason, it is possible to improve the printing speed as compared with the case where all the paper conveyance speeds are the synchronous conveyance speed. For this reason, even when printing is performed by transporting paper from an optional device located away from the main body device, the waiting time for first printing does not increase.
Further, according to the present invention, in the second and subsequent printing, the paper is transported only at the synchronous transport speed. For this reason, the sheet conveyance speed does not change, and there is almost no occurrence of noise caused by “pulling” of the sheet and “Z folding” due to the pushing of the sheet. Further, since no switching process is required, the control is simplified.
Therefore, according to the printing apparatus of the present invention, in the printing apparatus, it is possible to suppress problems and an increase in cost due to changing the paper conveyance speed and to improve the printing speed.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The present invention is applied to a printing apparatus represented by a printer apparatus, a copier apparatus, a facsimile apparatus, and the like. Here, a printer apparatus will be described as an example.

  FIG. 1 shows a configuration of a printer apparatus 1 according to the present embodiment. In FIG. 1, 11 is a printing apparatus main body (main body apparatus), and 12a to 12d are optional feeders (optional apparatus).

The printing apparatus body 11 receives an image signal from an external personal computer or the like, and forms a color image on a sheet from the image signal. The printing apparatus main body 11 includes an image processing unit 21, an image forming unit 22, a control unit 23, a paper tray 24, and a paper feed conveyance mechanism including a plurality of rollers and sensors. A sheet feeding / conveying mechanism (conveying means) picks up a roller 25 that picks up the paper stored in the paper tray 24, and retards that are separated into one sheet when two or more sheets taken out by the pickup roller 25 are fed. It includes various rollers such as a roller 26, a transport roller 27 that transports paper in the apparatus, a registration roller 28 that performs alignment correction, and a sensor for detecting rotation of each roller and transported paper. These rollers are driven to rotate under the control of the control unit 23. In addition, detection outputs of various sensors are supplied to the control unit 23. In addition, the control unit 23 stores various programs and data used by the control unit 23 (for example, in this embodiment, a time threshold for determining whether printing to be performed is the first printing or the like). A storage unit 33, an input unit 31 for inputting from various operation keys, and a display unit 32 for displaying various states are connected.
The control unit 23 comprehensively controls the operation of the printer apparatus 1 according to the present embodiment. In the present embodiment, the control unit 23 includes a sheet feeding / conveying mechanism of the printing apparatus main body 11 and option feeders 12a to 12d described later. The paper transport speed in the paper feed transport mechanism can be set to a synchronous transport speed and a high speed transport speed.

  The option feeders 12 a to 12 d are paper feeders of a type in which a plurality of feeders are stacked in multiple stages in the vertical direction, and are detachable from the printing apparatus main body 11. Here, four option feeders 12a to 12d are shown, but the number of option feeders is not limited to this.

  Each of the option feeders 12a to 12d has a control unit 51, a paper tray 52, and a paper feeding / conveying mechanism including a plurality of rollers and sensors. The paper feed and transport mechanism includes various rollers such as a pickup roller 53, a retard roller 54, and a transport roller 55, and sensors for detecting rotation of each roller and transported paper. These rollers are driven based on the control of the control unit 51. Further, the detection output of each sensor is sent to the control unit 51.

  The control unit 23 of the printing apparatus main body 11 is provided with a communication interface 34. The control interface 51 of the option feeders 12a to 12d is provided with a communication interface 59. When the option feeders 12a to 12d are attached to the printing apparatus main body 11, the communication interface 34 and the communication interface 59 are connected, and data is transmitted between the control unit 23 of the printing apparatus main body 11 and the control unit 51 of the option feeders 12a to 12d. Communication takes place.

  FIG. 2 is a block diagram showing a more detailed configuration of the option feeders 12a to 12d. As shown in FIG. 2, the control unit 51 includes a command receiving unit 62 that receives a command from the control unit 23 on the printing apparatus main body 11 side, and a paper feed and conveyance mechanism (a pickup roller 53, a retard roller 54, a conveyance). A conveyance speed setting unit 63 for setting the speed of the rollers 55 and the like is provided. The control unit 51 outputs drive signals for driving the pickup roller 53, the retard roller 54, and the transport roller 55, and this drive signal is sent through the drivers 57a to 57c to the pickup roller 53, the retard roller 54, and the transport roller. 55 is supplied. The conveyance speed at this time is set by the conveyance speed setting unit 63.

When the command receiving unit 62 receives the synchronous conveyance command, the paper conveyance mechanism is set to the synchronous conveyance speed in the conveyance speed setting unit 63, and the pickup roller 53, the retard roller 54, and the conveyance roller 55 are set at the synchronous conveyance speed. Driven.
The synchronous conveyance speed in the present invention and this embodiment is a conveyance speed for supplying paper to the intermediate transfer belt at a printable timing. In other words, the sheet is conveyed at the synchronous conveyance speed, and is supplied to the intermediate transfer belt at an optimal timing for printing.

When the command receiving unit 62 receives the high-speed conveyance command, the conveyance speed setting unit 63 sets the paper feed conveyance mechanism to the high-speed conveyance speed, and the pickup roller 53, the retard roller 54, The conveyance roller 55 is driven.
In addition, the high-speed conveyance speed in this invention and this embodiment is a conveyance speed faster than the above-mentioned synchronous conveyance speed.

  In FIG. 1, when printing is performed by the printer device 1 according to the embodiment of the present invention, an image signal from an external device is input to the interface 35. This image signal is sent to the image processing unit 21 via the control unit 23. The image processing unit 21 forms Y (yellow), C (cyan), M (magenta), and B (black) color signals from the input image signal. Each color signal is supplied to the exposure devices 36a, 36b, 36c, and 36d of the image forming unit 22, respectively.

  The image forming unit 22 is a tandem image forming unit, and includes four OPC drums 37a, 37b, 37c, and 37d corresponding to colors of Y (yellow), M (magenta), C (cyan), and B (black). , Exposure devices 36a, 36b, 36c, 36d, an intermediate transfer belt 38, drive rollers 39a, 39b around which the intermediate transfer belt 38 is wound, and a fixing roller 40.

  When an image is formed by the image forming unit 22, first, the surfaces of the OPC drums 37a, 37b, 37c, and 37d are uniformly charged. Then, the exposure devices 36a, 36b, 36c, and 36d scan and irradiate the OPC drums 37a, 37b, 37c, and 37d with laser light based on the image signals based on the image signals of the respective colors. When the laser beam is irradiated, the electric charge in the portion irradiated with the laser beam is lost, and latent images are formed on the OPC drums 37a, 37b, 37c, and 37d. Then, the toner of each color is developed on the OPC drums 37a, 37b, 37c, and 37d of each color, and a toner image of each color is formed. This toner image is primarily transferred to the intermediate transfer belt 38.

  On the other hand, among the paper stored in the paper tray 24 of the printing apparatus main body 11 or the paper stored in the paper tray 52 of the option feeders 12a to 12d, the paper in the selected tray is fed as described above. The mechanism is transported to the secondary transfer position of the image forming unit 22 (for example, the position of the registration roller 28). The toner image transferred to the intermediate transfer belt 38 is secondarily transferred onto the fed paper. The toner image transferred onto the paper is fixed by the fixing roller 40 and discharged.

  FIG. 3 shows processing of the control unit 23 on the printing apparatus main body 11 side when printing is performed by the printing apparatus according to the first embodiment of the present invention.

  In FIG. 3, the control unit 23 determines whether there is a print start request based on a print instruction from the input unit 31 or a print instruction from an external device connected to the interface 35 (step S1). If it is determined that there is, it is determined whether or not it is the first print (step S2). The first printing is printing after a predetermined time has elapsed since the above printing. That is, the control unit 23 compares the time threshold stored in the storage unit 33 with the elapsed time from the printing, and the time threshold stored in the storage unit 33 in advance. If it is longer, it is determined that the printing is the first sheet.

If it is determined in step S2 that the printing is for the first sheet, the paper feed conveyance time Ta is calculated (step S5). Here, the paper feed conveyance time Ta is transmitted from the control unit 23 of the printing apparatus main body 11 to the control unit 51 of the selected option feeders 12a to 12d, and then the paper is transferred to the printing apparatus main body 11. This is the time during which the sheet is conveyed to the secondary transfer position (for example, the position of the registration roller 28). This paper feed conveyance time Ta is calculated on the assumption that the synchronous conveyance speed is set.
The paper feed conveyance time Ta varies depending on the option feeders 12a to 12d (positional relationship between the printing apparatus main body 11 and the option feeders 12a to 12d). For this reason, the control unit 23 calculates the paper feed conveyance time Ta corresponding to the selected option feeders 12a to 12d. In addition, when the apparatus configuration is determined, the sheet feeding conveyance time Ta is determined for each of the option feeders 12a to 12d. For this reason, this paper feed conveyance time Ta may be stored in advance in the storage unit 33 or the like.

  After calculating the paper feed conveyance time Ta, the image forming time Tb is calculated (step S6). In the image forming time Tb, after the control unit 23 instructs the image forming unit 22 to start image forming processing, the image forming unit 22 performs charging, exposure, and toner image formation. Is the time until is transferred. The image forming time Tb needs to be recalculated when the printing apparatus main body 11 has a plurality of printing speeds such as the half speed mode, but is determined when the printing apparatus main body 11 does not have a plurality of printing speeds. The image forming time Tb may be stored in advance in the storage unit 33 or the like.

  In step S5, the paper feed transport time Ta is calculated. In step S6, if the image forming time Tb is calculated, it is determined whether the paper feed transport time Ta is longer than the image forming time Tb (step S7). In step S7, when the paper feed conveyance time Ta is longer than the image forming time Tb, the control unit 23 on the printing apparatus body 11 side sends a high-speed conveyance command to the control unit 51 on the selected option feeder 12a to 12d side. Then, the control unit 23 instructs the image forming unit 22 to start image formation (step S9).

  If it is determined in step S7 that the paper feed conveyance time Ta is shorter than the image forming time Tb, the process goes to step S15 to perform synchronous conveyance processing.

  When the selected control unit 51 on the option feeders 12a to 12d side receives the high-speed transport command in step S8, the paper feed / transport mechanism (pickup roller 53, retard roller 54, transport roller 55, etc.) rotates at high speed. And transport the paper at a high transport speed.

  In step S8, the control unit 23 on the printing apparatus main body 11 side transmits a high-speed conveyance command to the selected control unit 51 on the option feeders 12a to 12d, and starts image forming processing in step S9. Is calculated (step S10). That is, the control unit 23 switches to the synchronous conveyance speed so that the timing at which the sheet is conveyed to the secondary transfer position of the printing apparatus main body 11 and the timing at which the image forming unit 22 forms an image are synchronized. Is calculated. Then, it is determined whether or not this switching timing has been reached (step S11). Since such switching timing varies depending on the option feeders 12a to 12d (positional relationship between the printing apparatus main body 11 and the option feeders 12a to 12d), the control unit 23 switches the switching timing according to the selected option feeders 12a to 12d. Is calculated. In other words, in the printer apparatus 1 of the present embodiment, the sheet conveyance speed is set according to the selected option feeders 12a to 12d. For this reason, even when any of the option feeders 12a to 12d is selected, the switching timing can be calculated appropriately.

  When determining that the switching timing has been reached in step S11, the control unit 23 on the printing apparatus body 11 side transmits a synchronous conveyance command to the control unit 51 on the option feeders 12a to 12d side (step S12).

  When the selected control unit 51 on the option feeders 12a to 12d receives the synchronous transport command, the control unit 51 rotates the paper feed transport mechanism (pickup roller 53, retard roller 54, transport roller 55, etc.) so that the synchronous transport speed is reached. Reduce the speed and transport the paper at the synchronous transport speed.

As described above, when the conveyance speed is switched to the synchronous conveyance speed at the timing obtained in step S <b> 10, an image is formed by the timing at which the sheet is conveyed to the secondary transfer position of the printing apparatus main body 11 and the image forming unit 22. The image is secondarily transferred onto the intermediate transfer belt 38 at a suitable timing.
As described above, in the printer device 1 of the present embodiment, in the case of printing the first sheet, the sheet is transported by combining the synchronous transport speed and the high speed transport speed.

  Then, it is determined whether or not the next page is printed (step S13). If the next page is printed, the process proceeds to the next page (step S14), and the process returns.

  If it is continuous printing, it is determined in step S2 that the first page is not printed in printing the next page. In this case, the process goes to step S15 to perform synchronous conveyance processing. In the synchronous transport process, if the relationship between the paper feed transport time Ta and the image forming time Tb is (Ta> Tb), the synchronous transport command is preceded by the time difference between the paper feed transport time Ta and the image forming time Tb. If the relationship between the paper feeding and conveying time Ta and the image forming time Tb is (Tb> Ta), the process of preceding the image forming process is performed by the difference between the image forming time Tb and the paper feeding and conveying time Ta.

As described above, in the printer apparatus 1 according to the present embodiment, it is possible to convey a sheet at a high conveyance speed by printing the first sheet. For this reason, it is possible to improve the printing speed as compared with the case where all the paper conveyance speeds are the synchronous conveyance speed. Therefore, even when printing is performed by transporting paper from an option feeder (for example, option feeder 12d) located away from the printing apparatus main body 11, the waiting time for first printing does not increase.
Further, according to the printer device 1 of the present embodiment, in the second and subsequent printing, the paper is transported only at the synchronous transport speed. For this reason, the sheet conveyance speed does not change, and there is almost no occurrence of noise caused by “pulling” of the sheet and “Z folding” due to the pushing of the sheet. Further, since no switching process is required, the control is simplified.
Therefore, according to the printer device 1 of the present embodiment, it is possible to suppress problems and cost increases caused by changing the sheet conveyance speed, and to improve the printing speed.

  The embodiment of the present invention has been described above. However, the printing apparatus of the present invention is not limited to the illustrated example described above, and various modifications can be made without departing from the scope of the present invention. It is.

1 is a block diagram illustrating a configuration of a printing apparatus according to an embodiment of the present invention. FIG. 3 is a detailed functional block diagram of an option feeder provided in the printing apparatus according to the embodiment of the present invention. 3 is a flowchart used to describe a printing apparatus according to an embodiment of the present invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Printer apparatus, 11 ... Printing apparatus main body, 12a-12d ... Option feeder, 21 ... Image processing part, 22 ... Image forming part, 23 ... Control part, 24 ... Paper tray, 25 ... Pickup roller, 26 ... retard roller, 27 ... conveying roller, 28 ... registration roller, 31 ... input unit, 32 ... display unit, 34 ... communication interface, 35 ... interface, 36a to 36d ... exposure Device: 38 ... Intermediate transfer belt, 40 ... Fixing roller, 51 ... Control section, 52 ... Paper tray, 53 ... Pickup roller, 54 ... Retarding roller, 55 ... Conveying roller, 59 ... Communication interface

Claims (4)

In a printing apparatus comprising a main body device that prints on paper based on an image signal and an optional device that supplies paper to the main body device,
Conveying means for conveying the paper in the main body device and the optional device;
A control unit capable of setting the conveyance speed of the paper in the conveyance means to a synchronous conveyance speed and a high-speed conveyance speed;
The control unit determines whether or not the first sheet is printed when printing is performed by transporting the sheet from the option device to the main body apparatus, and the sheet is only performed when it is determined that the printing is the first sheet. The printing apparatus can be set to a high conveyance speed. When a plurality of the optional devices are installed,
The printing apparatus according to claim 1, wherein the control unit sets a sheet conveyance speed in the first printing in accordance with a positional relationship between the main body apparatus and the selected option apparatus.   3. The printing apparatus according to claim 1, wherein the control unit conveys the sheet by combining the high-speed conveyance speed and the synchronous conveyance speed when it is determined that the first printing is performed. 4. . The printing apparatus according to claim 1, wherein the control unit determines that the first printing is performed when a predetermined time has elapsed since the previous printing in the main body device.

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