JP4843566B2 - Image forming system - Google Patents

Description

  The present invention relates to an image forming system including a sheet storage device having a sheet correction mechanism and a switching gate and having a sheet stacking function, and an image forming apparatus.

  A conventional technique will be described with reference to FIGS. In these drawings, 1 is an image forming apparatus, 2 is a paper storage device, 3 is a paper correction mechanism, 4 is a paper storage unit, 5 is a switching gate, and 6 is a paper stacking table (hereinafter referred to as a stack table).

  On the stack table 6 while lowering the stack table 6 in accordance with the increase in the amount of sheets loaded on the stack table 6 on which the sheets fed from the image forming apparatus 1 typified by a printer or a copying machine are stacked and stored. An image forming system has been put into practical use in which a paper storage device 2 configured to store paper in a stacked manner is connected to improve handling and work efficiency of paper after printing.

  The image forming apparatus 1 used in this system has a double-sided printing mode in which toner images are recorded and formed on both front and back sides of paper, a sheet having a toner image facing upward, and a sheet having a toner image. It is configured such that the operator can freely select a paper discharge mode for discharging the paper downward.

  The image forming apparatus 1 generally employs a heat fixing roller system. The paper discharged through this type of heat fixing roller system is fed into the paper storage device 2 due to heat shrinkage due to heating, the direction of the constituent fibers of the paper itself, and the transport path system of the image forming apparatus 1. Tend to curl. When the tendency of the paper to curl is strong, the total number of sheets stacked on the paper storage device 2 is smaller than when the tendency to curl is weak, or a paper jam occurs when the paper storage device 2 is stacked. Sometimes. For this reason, the paper storage device 2 in which the paper correction mechanism 3 and the switching gate 5 for correcting the curl of the paper sent from the image forming apparatus 1 are mounted is put into practical use.

JP 2004-10242 A

  As described above, the curl of the paper sent from the image forming apparatus 1 to the paper storage device 2 is caused by the heat shrinkage due to the heating action, the constituent fiber direction of the paper itself, and the conveyance path system of the image forming apparatus 1. When there is a strong tendency to curl paper, if the paper correction mechanism 3 is always turned off (invalid) or on (valid) by the switching gate 5, the paper is loaded in the same direction (downward curl or upward curl). As a result, the total number of sheets to be stacked is reduced compared to the case where the curling tendency is weak, and paper alignment may be inferior.

  An object of the present invention is to provide a paper storage device that eliminates the disadvantages of the prior art and has good paper alignment.

In order to achieve the above object, the present invention provides an image forming apparatus having a sheet storage unit, sheet correcting means provided downstream of the image forming apparatus, and switching for switching sheet conveyance to the sheet correcting means based on post-processing information. In an image forming system including a gate, a control unit that controls the switching gate, and a paper storage device having a paper stacking unit, the image forming device is configured to output the paper every time one sheet is sent from the paper storage unit. When the post-processing information for the paper is transmitted to the paper storage device, and the post-processing information is not changed, the control unit controls the paper correction unit for each paper transported to the paper storage device. intended to the path which the paper passes, characterized in that to control the switching gate to transport to the path that does not pass the intersection each other, to stack a plurality of sheets in the sheet storing device That.

  According to the present invention, it is possible to achieve good sheet alignment for any sheet sent from the image forming apparatus.

  As described above, the present invention relates to an image forming system including a sheet storage device having a sheet correction mechanism and a switching gate and having a sheet stacking function and an image forming apparatus, after being sent from the image forming apparatus to the sheet storage apparatus. Based on the processing information, the sheet storage device is configured to stack the curled sheets in different directions by alternately controlling the sheet correction mechanism switching gates OFF / ON for each sheet.

  The operation of this embodiment relating to the control of the switching gate 5 of the sheet correction mechanism 3 when a sheet is fed into the sheet storage device 2 will be described with reference to FIGS. FIG. 1 is a front view showing a section of a paper storage device 2 and an image forming apparatus 1 according to an embodiment of the present invention, FIG. 2 is a cross-sectional view of the paper storage device 2, and FIG. 4 is a cross-sectional view of the paper storage device 2 of FIG. 2 when the paper correction mechanism is OFF, FIG. 5 is a cross-sectional view of the paper storage device 2 of FIG. 2 when the paper correction mechanism is ON, and FIG. FIG. 7 is a configuration diagram of control units of the sheet storage device 2 and the image forming apparatus 1 when the sheet passes through the sheet correction mechanism 3.

  The image forming apparatus 1 is configured to record and form a toner image on both front and back sides of a sheet of paper, to discharge a sheet having a toner image facing upward, or to discharge a sheet having a toner image facing downward. It is configured so that the operator can freely select a paper discharge mode for paper. Further, the image forming apparatus 1 of the present embodiment employs a heat fixing roller system.

  The sheet storage device 2 is connected immediately after the image forming apparatus 1, and descends the stack table 6 as the amount of sheets loaded on the stack table 6 that stacks and stores sheets fed from the image forming apparatus 1 increases. However, the stacker 6 has a sample tray 7 that does not have a mechanism for stacking and storing sheets on the stack table 6 and a table mechanism. The paper storage device 2 is provided with a paper correction mechanism 3 for correcting the curl of the paper fed from the image forming apparatus 1. The paper correction mechanism 3 is switched before or after the path of the paper correction mechanism 3. For this purpose, a switching gate 5 is mounted. The switching gate 5 has a mechanism that is switched by a driving means (not shown). In this embodiment, a solenoid is used as the driving means.

  These devices are controlled by connecting each device with an interface signal line as shown in FIG. The interface signal line includes a post-processing information signal line and a sequence signal line. The post-processing information signal line is a signal line for serially transmitting data necessary for the paper storage device 2 to perform a post-processing operation. Specific information includes post-processing information such as paper width, paper length, paper continuous amount, discharge mode, print mode (double-sided printing or single-sided printing), and printing operation instructions such as operation start instruction, stop instruction, and reset instruction. There is. The sequence signal lines are a reset signal for resetting the paper storage device 2, a paper discharge signal for signaling that paper is discharged from the image forming apparatus 1 to the paper storage device 2, and an image indicating that the state of the paper storage device 2 has changed. There is a status read request signal to contact the forming apparatus 1.

  The image forming apparatus 1 receives a command or information related to printing from a host device (not shown) and performs a printing operation according to the command or information. The present invention relates to the control of the switching gate 5 of the paper correction mechanism 3 of the paper storage device 2, and a description of the interface processing between the host device and the image forming apparatus 1 is omitted.

  The operation of the switching gate 5 of the sheet correction mechanism 3 of the sheet storage device 2 will be described based on the above control configuration. When printing is started, a print start instruction command is transmitted from the image forming apparatus 1 to the paper storage device 2 through the post-processing information signal line. With this command, the paper storage device 2 raises the stack table 6 and prepares to receive paper. It starts and informs the image forming apparatus 1 that the preparation is completed.

When the image forming apparatus 1 receives a report of completion of preparation, the image forming apparatus 1 sends a sheet from the sheet storage unit 4 and transmits post-processing information for the sheet to the sheet storage apparatus 2 each time a sheet is sent. To do. Paper width of the post-processing information, paper length, the paper ream weight, the discharge mode, the paper storage device 2 from the post-processing information, such as single-sided printing and two-sided printing, that controls the switching gate 5 operation of the sheet correcting mechanism 3. 1 sheet of paper fed into the paper storage unit 2 switches the switching gate 5 of the sheet correcting mechanism 3 before reaching the gate 5 switching the sheet leading end in the sheet correcting mechanism OFF side (disabled side), the trailing edge of the sheet This state is maintained until the time passes (the state of FIGS. 4, 6A and 6C). Next, for the second sheet whose post-processing information is not changed, before the leading edge of the sheet reaches the switching gate 5, the switching gate 5 of the sheet correcting mechanism 3 is switched to the sheet correcting mechanism ON side (effective side), and the trailing edge of the sheet This state is maintained until the time passes (the state shown in FIGS. 5, 6B and 6D). The above is performed particularly when the paper has a strong tendency to curl.

  Thereafter, when there is no change in the post-processing information, before the leading edge of the sheet reaches the switching gate 5, the switching gate 5 of the sheet correction mechanism 3 is alternately switched for each sheet and the state is maintained until the trailing edge of the sheet passes. By holding the sheet curl, the sheet curl sent to the stack table 6 or the sample tray 7 is alternately stacked downward and upward (state shown in FIG. 3C). The height difference Hc between the paper center and the paper edge when the paper curls are alternately stacked downward and upward (state shown in FIG. 3C) is the height difference between the paper center and the paper edge when the paper curls are stacked only with the downward curl. Good sheet alignment can be achieved by lowering the height difference Hb between the center of the sheet and the edge of the sheet Hb (state of FIG. 3B) in the state of being stacked only by upward curling (state of FIG. 3A). Will be able to get.

1 is a front view of a section of a sheet storage device and an image forming apparatus according to an embodiment of the present invention. It is sectional drawing of the paper storage apparatus. FIG. 6 is a diagram illustrating a loaded state of curled paper. FIG. 6 is a cross-sectional view of the paper storage device when the paper correction mechanism is OFF. FIG. 6 is a cross-sectional view of the paper storage device when the paper correction mechanism is ON. 6 is a timing chart when a sheet passes through a sheet correction mechanism of the sheet storage device. FIG. 3 is a configuration diagram of a control unit of a sheet storage device and an image forming apparatus.

Explanation of symbols

  Reference numeral 1 denotes an image forming apparatus, 2 denotes a paper storage device, 3 denotes a paper correction mechanism, 4 denotes a paper storage unit, 5 denotes a switching gate, 6 denotes a paper stacking table (stack table), and 7 denotes a sample tray.

Claims (1)

An image forming apparatus having a sheet storage unit, a sheet correcting unit provided downstream of the image forming apparatus, a switching gate for switching sheet conveyance to the sheet correcting unit based on post-processing information, and a control unit for controlling the switching gate If, in an image forming system including a sheet accommodating apparatus having a sheet stacking means, wherein the image forming apparatus, each delivering 1 the sheets from said sheet storing section, the paper accommodating the post-processing information to said sheet When there is no change in the post-processing information transmitted to the apparatus, the control means, for each sheet conveyed to the sheet storage apparatus, the path through which the sheet passes through the sheet correction means and the path through which the sheet does not pass The image forming system , wherein the switching gate is controlled so as to be alternately conveyed, and a plurality of sheets are stacked on the sheet storage device .

Images