JP2001180097A - Printing machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect in-machine retaining error even when a conveyance of a printing sheet is stopped between a feed paper sensor and a paper discharge sensor and a power source is turned off in this state or the like. SOLUTION: The printing machine comprises a sheet supplying mechanism for conveying a printing sheet to a printing mechanism, the printing mechanism for printing the sheet supplied by the supplying mechanism, a sheet delivering mechanism for conveying the sheet printed by the printing mechanism to a sheet delivering position, the feed paper sensor provided at the detecting position of the sheet supply conveying route by the supplying mechanism, and the sheet discharge sensor provided at the detecting position of the sheet discharge conveying route by the delivering mechanism. In this case, in the printing step, the number of the supply printing sheets is calculated according to the detected result of the paper sensor, and the number of the discharge printing sheets is calculated according to the detected result of the discharge sensor. The number of the supply sheets and the number of the discharge sheets are stored in a memory means when the printing operation is completed. At the next printing starting time point, the number of the supply sheets stored in the memory means is compared with the number of the discharge sheets stored in the memory means to detect the retaining error in the machine.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printing apparatus for transporting printing paper at a paper feeding position to a printing mechanism and transporting the printed printing paper to a paper discharging position for stocking. The present invention relates to an error detection technique.

[0002]

2. Description of the Related Art FIG. 13 shows a schematic diagram of a main part of a conventional printing apparatus of this kind. In FIG. 13, a paper feed mechanism A that transports a plurality of print papers 1 stacked at a paper feed position one by one to a print mechanism B, and performs print processing on the print paper 1 fed by the paper feed mechanism A. It has a printing mechanism B and a paper discharge mechanism C that conveys the printing paper 1 printed by the printing mechanism B to a paper discharge position. The paper feed mechanism A has a paper feed table 2 above which is a paper feed position, and a plurality of print sheets 1 are stacked on the paper feed table 2. The paper feed table 2 is provided with a paper presence / absence sensor S1 for detecting whether or not the print paper 1 is present at the paper feed position. Then, a scraper 3 is pressed against the uppermost position of the printing paper 1 loaded on the paper feeding table 2, and a downstream roller 4 with which the lower surface of the printing paper 1 conveyed comes in contact downstream with the rotation of the scraper 3. Is arranged. A guide roller 5 and a timing roller 6 are disposed further downstream of the sub roller 4. The guide roller 5 can move between the pressure contact position and the separation position with respect to the timing roller 6. That is, a substantially straight line connecting between the scraper 3 and the blow roller 4 and between the guide roller 5 and the timing roller 6 on the downstream side is defined as a sheet feeding path, and the sheet feeding path is set as a detection position. A paper sensor S2 is provided.

[0003] The printing mechanism B has a plate cylinder 7 rotatably provided and a paper cylinder 8 disposed below and also rotatably provided. A part of the surface is substantially close. A screen (not shown) is stretched on the outer peripheral surface of the plate cylinder 7, and an ink supply means (not shown) for supplying ink to the screen (not shown) is provided inside the plate cylinder 7. Have been. Further, an intermediate pressing roller 9 is provided rotatably inside the plate cylinder 7,
This middle pressing roller 9 is a screen (not shown) from the inside.
And a home position separated from a screen (not shown). A stencil sheet (not shown) is provided on a screen on the outer peripheral surface of the plate cylinder 7 so as to be freely wound. Also, the paper cylinder 8
Is provided with a paper clamp unit 10, and the printing paper 1 is provided so as to be freely wrapped with the leading end clamped by the paper clamp unit 10.

The paper discharge mechanism C has an upper guide section 11 and a lower guide section 12 which are arranged close to the plate cylinder 7 and the paper cylinder 8, and the printing paper printed by the upper and lower guide sections 11, 12. 1 is guided to the space inside the upper and lower guide portions 11 and 12. Downstream of the vertical guides 11 and 12, a pair of upper and lower paper discharge rollers 13 and 14 are provided at two locations. That is, the space inside the upper and lower guides 11 and 12 and the space between the pair of upper and lower paper discharge rollers 13 and 14 are used as a paper discharge conveyance path, and a paper discharge sensor S3 that uses the paper discharge conveyance path as a detection position is provided. At the downstream of the paper discharge rollers 13 and 14, the paper discharge table 1 is provided.
5 is provided, and the upper position of the paper discharge table 15 is a paper discharge position.

Next, a printing operation in the above configuration will be described. While the plate cylinder 7 and the paper cylinder 8 rotate in the direction of the arrow in FIG. 13, the scraper 3 rotates, so that a conveying force is applied to the loaded printing paper 1, and the printing paper 1 is moved from the paper feed table 2 by the sabaki action of the sabaki roller 4. Only the uppermost printing paper 1 is conveyed. The leading end of the conveyed printing paper 1 stops moving while being sandwiched between the guide roller 5 and the timing roller 6, and then the rotation of the scraper 3 causes the printing paper 1 to be deflected. Stop at

Next, the timing roller 6 and the guide roller 5 rotate, and the leading end of the printing paper 1 is conveyed toward the outer peripheral surface of the paper cylinder 8. In this operation process, the scraper 3 is idled so that the back tension is not applied to the printing paper 1. When the leading edge of the printing paper 1 reaches the outer peripheral surface of the paper cylinder 8, the paper clamp unit 10 of the paper cylinder 8 clamps the leading edge of the printing paper 1. The clamped printing paper 1 is a paper cylinder 8
The ink is transferred by receiving printing pressure from the intermediate pressing roller 9 when passing through the substantially outer peripheral portion of the plate cylinder 7 and the paper cylinder 8, and an image is printed. In this operation process, the back tension is not applied to the printing paper 1 so that
The guide roller 5 is located at the separated position.

When the leading edge of the printing paper 1 passes through a portion of the outer peripheral surface substantially close to the plate cylinder 7 and the paper cylinder 8, the paper clamp unit 10 releases the clamp, and the leading edge of the printing paper 1 is caused by its own elastic return deformation or the like. Move away from the torso 8. The printing paper 1 separated from the paper cylinder 8 is guided by upper and lower guide portions 11 and 12 and guided between a pair of upper and lower discharge rollers 13 and between a pair of upper and lower discharge rollers 14 downstream thereof. , 14 continue to move and are discharged to the paper discharge table 15.

In the above-described printing operation process, whether or not the printing paper 1 is normally fed is monitored by the paper feeding paper sensor S2, and whether or not the paper is normally discharged is checked. Monitoring is performed by the sensor S3. When the conveyance of the printing paper 1 is stopped along the paper feeding conveyance path as shown in FIG. 14A for some reason during the printing operation, the paper feeding paper sensor S2 detects this and the paper feeding sensor S2 shown in FIG. When the conveyance of the printing paper 1 is stopped in the paper discharge conveyance path as in (3), the paper discharge sensor S3 detects this. Even if the power is turned off despite the above-described transport error, the next time the power is turned on, the detection outputs of the paper feed paper sensor S2 and the paper discharge sensor S3 are checked to determine the residual paper feed error and the paper discharge. Residual errors can be detected.

[0009]

However, FIG.
(2) As shown in (2), the conveyance is stopped between the paper feed paper sensor S2 and the paper discharge sensor S3 and at both non-detection positions,
In this state, the power may be turned off, or the printing operation may be terminated while the power is on. In this case, at the time of the next power-on or the start of the next printing operation, it is recognized that there is no residual error even if the detection outputs of the paper feed paper sensor S2 and the paper ejection sensor S3 are checked, so the next printing operation is executed. However, there is a problem that a jam occurs due to the remaining paper. In particular, when the printing paper 1 is a small size such as a postcard or a business card, or when the printing paper 1 has the plate cylinder 7 and the paper cylinder 8, the distance between the paper feeding paper sensor S2 and the paper discharging sensor S3 has to be set large. In the case of a device that cannot be obtained, the probability of occurrence of the above-mentioned situation increases.

In view of the above, the present invention has been made to solve the above-mentioned problem, and the present invention has been made to stop conveyance between a paper feed sensor and a paper discharge sensor and to both non-detection positions,
An object of the present invention is to provide a printing apparatus capable of detecting an in-machine residual error even when the power is turned off or the printing operation is terminated when the power is turned on in this state.

[0011]

According to a first aspect of the present invention, there is provided a paper feed mechanism for transporting a plurality of print sheets stacked at a paper feed position one by one to a print mechanism, and paper fed by the paper feed mechanism. A printing mechanism for performing a printing process on the printing paper, and a paper discharging mechanism for transporting the printing paper printed by the printing mechanism to a paper discharging position, wherein a paper feeding path by the paper feeding mechanism is set as a detection position; In a printing apparatus provided with a paper feed sensor for detecting conveyance of print paper, a discharge conveyance path by the paper discharge mechanism as a detection position, and a discharge sensor for detecting conveyance of the print paper, The number of paper feeds of the printing paper is calculated based on the detection result of the paper supply paper sensor, and the number of paper discharges of the print paper is calculated based on the detection result of the paper discharge sensor. Remember the number Stored in, the next printing operation start time, wherein the detection of the cabin residual error by comparing the paper feed quantity and ejected sheets stored in the storage means.

In this printing apparatus, the number of sheets fed and the number of sheets discharged at the time of completion of the printing operation are stored in the storage means, and the number of sheets fed and discharged at the time of starting the next printing operation are stored in the storage means. Since the number of sheets is compared with the number of sheets, it is possible to detect whether or not there is a print sheet that has been conveyed and stopped without being detected by the paper supply paper sensor or the paper ejection sensor, that is, an in-machine residual error.

According to a second aspect of the present invention, in the printing apparatus according to the first aspect, at the start of the printing operation, the paper feed paper sensor detects that there is no print paper, and the paper discharge sensor has no print paper. Is detected, the presence or absence of an in-machine residual error by the storage means is checked.

In this printing apparatus, in addition to the operation of the first aspect of the present invention, the residual error in the apparatus is detected when there is no residual paper feed error by the paper feed sensor and no residual paper discharge error by the paper discharge sensor. Can recognize the position of.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings.

1 to 12 show an embodiment of the present invention. FIG. 1 is a schematic configuration diagram of a main part of a stencil printing apparatus, FIG. 2 is a schematic circuit block diagram of the printing apparatus, FIG. 4 is a flowchart of a print continuation determination, FIG. 5 is a flowchart of a paper supply / discharge error check, FIG. 6 is a flowchart of a primary paper jam determination, FIG. 7 is a flowchart of a printing pressure motor return determination, and FIG. FIG. 9 is a flowchart for determining a paper ejection jam, FIG. 10A is a schematic operation flowchart when the power of the printing apparatus is turned on, FIG. 10B is a flowchart when the power of the printing apparatus is turned off, and FIG. FIG. 12 is a time chart from the start of printing.

In FIG. 1, the stencil printing apparatus mainly comprises a plate making mechanism D (shown in FIG. 2), a paper feeding mechanism A, a printing mechanism B, a paper discharging mechanism C, and a plate discharging mechanism E (shown in FIG. 2). Have been.

The stencil making mechanism D reads the information of the original as an electric signal, and pierces a stencil sheet (printing stencil) based on the read information to create a desired stencil sheet. This stencil sheet is mounted on the outer peripheral surface of the plate cylinder 7 of the printing mechanism B.

The paper feed mechanism A has a paper feed table 2 above which is a paper feed position, and a plurality of print sheets 1 are stacked on the paper feed table 2. The paper feed table 2 is provided with a paper presence / absence sensor S1 for detecting whether or not the print paper 1 is present at the paper feed position. A scraper 3 is pressed against the uppermost position of the printing paper 1 loaded on the paper feed table 2, and the lower surface of the printing paper 1 which is conveyed a little downstream by rotation of the scraper 3 abuts against the scraper 3. 4 are arranged. The scraper 3 is rotated by the driving force of the primary paper feed motor M1. A guide roller 5 and a timing roller 6 are disposed further downstream of the sub roller 4. The guide roller 5 can move between the pressure contact position and the separation position with respect to the timing roller 6. The timing roller 6 is configured to be rotated at a predetermined timing by a driving force of a main motor M2 described below. That is, the scraper 3
A substantially straight line that connects between the guide roller 5 and the timing roller 6 and the downstream between the guide roller 5 and the timing roller 6 is a paper feed path, and the paper feed sensor S2 having the paper feed path as a detection position. Is provided. The output of the paper feed sensor S2 is ON when the printing paper 1 is detected,
It is off when the printing paper 1 is not detected.

The printing mechanism B has a plate cylinder 7 rotatably provided and a paper cylinder 8 disposed below and also rotatably provided. A part of the surface is substantially close. The plate cylinder 7 and the paper cylinder 8 are configured to rotate synchronously in the arrow direction of FIG. The rotational positions of the plate cylinder 7 and the paper cylinder 8 are detected by an encoder 16 (shown in FIG. 2). A screen (not shown) through which ink can pass under pressure is stretched on the outer peripheral surface of the plate cylinder 7, and ink is supplied to the screen (not shown) inside the plate cylinder 7. An ink supply unit (not shown) is provided. An intermediate press roller 9 is rotatably provided inside the plate cylinder 7, and the intermediate press roller 9 is provided with a printing pressure motor M3.
The printing device is movably provided between a printing pressure position for pressing a screen (not shown) by the driving force of the above and a home position separated from the screen (not shown).
Further, the paper cylinder 8 is provided with a paper clamp unit 10, and the printing paper 1 is provided so as to be freely wrapped with the leading end clamped by the paper clamp unit 10.

The paper discharge mechanism C has an upper guide portion 11 and a lower guide portion 12 which are arranged close to the plate cylinder 7 and the paper cylinder 8, and the printing paper printed by the upper and lower guide portions 11, 12. 1 is guided to the space inside the upper and lower guide portions 11 and 12. Downstream of the vertical guides 11 and 12, a pair of upper and lower paper discharge rollers 13 and 14 are provided at two locations. The lower discharge rollers 13 and 14 are configured to rotate by the driving force of the discharge motor M4. Discharge roller 13,
A discharge tray 15 is provided downstream of the discharge tray 15.
The upper position is the paper discharge position. That is, the space inside the upper and lower guides 11 and 12 and the space between the pair of upper and lower paper discharge rollers 13 and 14 are used as a paper discharge conveyance path, and a paper discharge sensor S3 that uses the paper discharge conveyance path as a detection position is provided. The output of the paper ejection sensor S3 is on when the printing paper 1 is detected, and is off when the printing paper 1 is not detected.

A stencil discharging mechanism E (shown in FIG. 2) strips the stencil sheet mounted on the outer peripheral surface of the plate cylinder 7, conveys the stripped stencil sheet to a stencil box (not shown), and discharges the stencil sheet. .

In FIG. 2, the operation panel 20 has an input means and a display means. The input means selects various modes (for example, a printing operation mode) and inputs the number of prints. Output to the control means (CPU) 21. The control means 21 controls display information on the operation panel 20 and controls the above-described plate making mechanism D, sheet feeding mechanism A, printing mechanism B, sheet discharging mechanism C, and plate discharging mechanism E. The driving of each of the motors M1 to M4 is controlled by the control means 21. The detection output of each of the sensors S1 to S3 is
Is output to Further, the control means 21 includes a ROM 22 and an R
It is connected not only to the AM 23 but also to the storage means 24 so that reading and writing of these data can be controlled. The storage means 24 is constituted by, for example, a non-volatile memory, and is configured to retain the stored contents even when the power is off. Then, when the printing operation mode is selected, or when the power is turned on / off, the control unit 21 controls the mechanisms A to E to execute the flow operations as shown in FIGS. Next, the contents will be described with reference to the time chart of FIG. 12 and FIGS.

When desired data such as the number of prints is input and the printing operation mode is selected, first, after confirming that the paper presence sensor S1 is on, the paper supply paper sensor S2 is off, and the paper ejection sensor S3 is off, , The main motor M2 is driven to rotate the plate cylinder 7 and the paper cylinder 8, and the discharge motor M
4 drives the paper discharge rollers 13 and 14 to rotate. Then, as shown in FIG. 3, the storage of the number of fed sheets and the storage of the number of discharged sheets in the RAM 23 are reset to “0” (step S1,
S2) When the angle of the paper cylinder 8 becomes 0 degree, the printing continuation is determined (steps S3 and S4).

As shown in FIG. 4, the continuation of printing is determined by checking the output of the paper sensor S1 (step S20).
If it is off (no paper), the stop flag is turned on (step S20). Next, it is checked whether the remaining number of printed sheets is 0 (zero) (step S22). If the remaining number of printed sheets is not 0 (zero), the stop flag is on and the error flag is not on. It is determined that printing is to be continued (steps S23 and S24). If the remaining number of printed sheets is 0 (zero), the stop flag is on, or the error flag is on, the process proceeds to the print end process (step S6 in FIG. 3). If the print end processing is performed (step S6),
The driving of the main motor M2 and the driving of the paper discharge motor M4 are stopped, and the number of stored papers and the number of discharged papers are written and stored in the storage means 24 as shown in FIG. 3 (steps S7 and S8). .

If it is determined that printing is to be continued, as shown in FIG. 3, when the angle of the paper cylinder 8 becomes 30 degrees, the driving of the primary paper feed motor M1 is started (steps S9 and S1).
0). Then, the scraper 3 rotates to apply a conveying force to the stacked printing papers 1 and to convey only the uppermost printing paper 1 from the paper feed table 2 by the sabaki action of the sabaki rollers 4. Then, the leading edge of the printing paper 1 is detected by the paper feeding paper sensor S2, and the driving of the primary paper feeding motor M1 is stopped based on the detection timing. As a result, the leading end of the printing paper 1 is stopped while being sandwiched between the guide roller 5 and the timing roller 6 and the printing paper 1 is bent.

When the angle of the paper cylinder 8 reaches 60 degrees, a paper supply / discharge error check is performed as shown in FIG. 3 (steps S11 and S12). The paper supply / discharge error check is performed from the second print onward as shown in FIG. 5 (step S3).
0), RAM if the paper discharge sensor S3 is ON (paper is present)
In step S31, S32 is incremented by "+1". That is, at the position where the angle of the paper cylinder 8 is 60 degrees, the immediately preceding printing paper 1 is
, It is checked whether or not the sheet has been normally ejected, and if the sheet is normally ejected, the number of ejected sheets is counted. If the paper ejection sensor S3 is off (there is no paper), a paper jam error has occurred when the paper sensor S2 is on, so the error flag is turned on (steps S33 and S34), and the paper is fed. When the paper sensor S2 is off, a paper ejection error has occurred, so the error flag is turned on (step S3).
3, S35). In this case, the primary feed motor M1 is stopped, and the return flag of the printing pressure motor M3 is turned on (steps S36 and S37). Then, the process proceeds to the above-described printing end process (step S6 in FIG. 3).

When the angle of the paper cylinder 8 becomes 115 degrees, as shown in FIG. 3, a primary paper jam determination process and a printing pressure motor return determination process are performed (steps S13, S14, S1).
5). As shown in FIG. 6, the primary paper jam determination is performed by checking whether or not the output of the paper paper sensor S2 is ON (paper is present) after the operation of the primary paper motor M1 is stopped.
If it is on, the number of stored sheets in the RAM 23 is incremented by "+1" (steps S41 and S42). That is, if the primary paper feed of the printing paper 1 is normally performed,
Since the leading end of the printing paper 1 passes the detection position of the paper supply paper sensor S2 just before the angle of the paper cylinder 8 is less than 115 degrees,
When the paper is normally fed, the number of fed sheets is counted. or,
If the paper supply paper sensor S2 is off (no paper), an error in paper supply empty conveyance has occurred, and the error flag is turned on (steps S41 and S43). In this case, the return flag of the printing pressure motor M3 is turned on (step S4).
4). Then, the processing shifts to the above-described printing end processing (FIG. 3).
Step S6).

In the printing pressure motor return determination, as shown in FIG. 7, it is checked whether or not the return flag of the printing pressure motor M3 is ON, and if it is ON, the printing pressure motor M3 is returned to the home position (step S45, step S45). S46). If the return flag of the printing pressure motor M3 is off, such an operation is not performed.

When the angle of the paper cylinder 8 becomes 125 degrees, as shown in FIG. 3, a pressing operation process of the printing pressure motor M3 is performed (steps S16 and S17). As shown in FIG. 8, the pressing operation of the printing pressure motor M3 is performed from the second print onward (step S50), and the designated value of the printing pressure motor M3 is calculated and moved to the calculated designated value. There are (steps S51, S52). By the movement of the printing pressure motor M3, the intermediate pressing roller 9 is positioned at a pressing position for pressing a screen (not shown) from the inside.

On the other hand, when the printing paper 1 is normally conveyed, when the angle of the paper cylinder 8 is about 125 degrees,
The driving force of the main motor M2 can be transmitted to the timing roller 6, and the timing roller 6 and the guide roller 5 rotate. Due to this rotation, the leading end of the printing paper 1 is
Is conveyed toward the outer peripheral surface. In this operation process, the scraper 3 is idled so that the back tension is not applied to the printing paper 1. The leading end of the printing paper 1 is the paper cylinder 8
, The paper clamp unit 10 of the paper cylinder 8 clamps the leading end of the printing paper 1. The clamped printing paper 1 is moved together with the rotation of the printing drum 8, and receives printing pressure from the intermediate pressing roller 9 when passing through a substantially adjacent outer peripheral portion between the printing drum 7 and the printing drum 8, and the ink is transferred to print the image. Is done. In this operation process, the guide roller 5 is located at the separated position so that the back tension is not applied to the printing paper 1.

When the leading end of the printing paper 1 passes through a portion of the outer peripheral surface substantially close to the plate cylinder 7 and the paper cylinder 8, the paper clamp unit 10 releases the clamp, and the leading end of the printing paper 1 is resiliently deformed by itself. Move away from the torso 8. The printing paper 1 separated from the paper cylinder 8 is guided by upper and lower guide portions 11 and 12 and guided between a pair of upper and lower discharge rollers 13 and between a pair of upper and lower discharge rollers 14 downstream thereof. , 14 continue to move and are discharged to the paper discharge table 15.

When the angle of the paper cylinder 8 reaches 300 degrees, a paper discharge jam determination process is performed as shown in FIG. 3 (steps S18 and S19). In the paper discharge jam determination, as shown in FIG. 9, it is checked whether or not the paper discharge sensor S3 is ON (paper is present). If the paper discharge sensor S3 is ON, the paper discharge, that is, an error is set as an error flag (step S60, S61). Then, the process proceeds to the above-described printing end process (step S6 in FIG. 3). If the paper discharge sensor S3 is off (there is no paper), the number of prints in the RAM 23 is decremented by "-1" on condition that it is not the first print (steps S62 and S62).
63). In other words, at the position where the angle of the paper cylinder 8 is 300 degrees, it is the timing at which the printing paper 1 has finished passing the position of the paper ejection sensor S3. The number of prints is counted when the paper is discharged to the printer.

In this way, the printing operation for the predetermined number of prints is normally executed, and when the remaining number of prints becomes 0 (zero) (step S22 in FIG. 4), the processing shifts to the above-described print end processing. When the stop flag is turned on or the error flag is turned on for various reasons described above, the printing operation is shifted to the printing end process in the middle without performing the printing operation for the predetermined number of prints. Regardless of the cause of the printing end, when the process is shifted to the printing end processing, as shown in FIG. 3, the number of stored sheets and the number of discharged sheets are written and stored in the storage unit 24 (steps S7 and S8). .

When the power is turned off, FIG.
As shown in (B), the number of stored sheets and the number of stored sheets at that time are written and stored in the storage unit 24 by the interrupt processing (steps S70 and S71). That is,
Even when the power is turned off during the printing operation mode without shifting to the printing end process (step S6 in FIG. 3), the number of stored sheets and the number of stored sheets at that point are stored in the storage unit 24. Is done.

Next, the operation when the power is turned on will be described. As shown in FIG. 10A, when the power is turned on, the control device (CPU) 21 is initialized, and a remaining sheet confirmation process is performed (steps S80 and S81). After the remaining sheet confirmation processing is performed, key input processing, panel display processing, and plate making / printing operation processing (described in detail above) are performed (steps S82, S83, S84), and after the plate making / printing operation processing is performed, A paper confirmation process is performed. That is, the remaining paper confirmation process is performed when the power is once turned off and then turned on again, and when a new printing operation process is performed without turning off the power.

The remaining sheet confirmation processing is performed as shown in FIG.
If the paper supply paper sensor S2 is on, it is determined that a paper supply residual error has occurred, and an error flag is turned on (step S9).
0, S91), and when the paper discharge sensor S3 is on, it is determined that a paper discharge residual error has occurred, and an error flag is turned on (steps S92, S93). If both the paper feed sensor S2 and the paper discharge sensor S3 are off, the storage means 24 calls the stored paper number and the discharged paper number (step S9).
(4, S95), it is checked whether the number of stored sheets is smaller than the number of stored sheets (step S96). If the number of stored sheets is smaller than the number of stored sheets, it is determined that there is a residual error in the apparatus, and an error flag is turned on (step S9).
7). That is, the reason why the number of stored papers and the number of stored papers do not match even though there is neither a residual paper feed error as shown in (1) of FIG. 14 nor a remaining paper discharge error as shown in (2) of FIG. This means that the print paper 1 remains at a position that is not detected by the paper feed paper sensor S2 and the paper discharge sensor S3.

As described above, the conveyance is stopped between the paper feed paper sensor S2 and the paper discharge sensor S3 and to both of the non-detection positions. In this state, the power is turned off or the power is turned on but the printing is stopped. Even when the operation is terminated, an in-machine residual error can be detected.

As described above, according to the above-described embodiment, at the start of the printing operation, the paper feed sensor S2 detects that there is no print paper, and the paper discharge sensor S3 detects that there is no print paper. Although it is configured to check the presence or absence of an in-machine residual error by the storage means 24, at the start of the printing operation, the number of paper feeds and the number of papers stored in the storage means 24 are simply compared with each other, and if they do not match, the internal You may comprise so that it may be set as a residual error. However, if the paper feed sensor S2 detects that there is no print paper and the paper discharge sensor S3 detects that there is no print paper as in the above-described embodiment, the remaining paper error is detected. The location of the error can also be recognized.

According to the above-described embodiment, the printing mechanism B has the plate cylinder 7 and the paper cylinder 8 which are arranged at substantially close positions.
A stencil sheet (printing stencil) is wound on the outer peripheral surface of the printing paper 1, and the printing paper 1 conveyed from the paper feeding mechanism A to the printing drum 7 is pressed against the printing drum 7 while being clamped to the printing drum 8. Then, printing is performed by transferring the ink to the printing paper 1 in the process of passing the pressure contact. In the printing apparatus using such a plate cylinder 7 and a paper cylinder 8, the distance between the paper feed paper sensor S2 and the paper discharge sensor S3 has to be set to be large, and the above-mentioned probability of occurrence of the residual in the machine is reduced. Although high, it is effective because this in-machine residual error can be detected.

According to the above embodiment, the case where the present invention is applied to the stencil printing apparatus has been described, but it is needless to say that the present invention can be similarly applied to a printing apparatus other than the stencil printing apparatus.

[0042]

As described above, according to the first aspect of the present invention, a paper feeding mechanism for transporting printing paper one by one to a printing mechanism, and a printing process for printing paper fed by the paper feeding mechanism. And a paper discharge mechanism for transporting the print paper printed by the print mechanism to a paper discharge position.The paper transport path by the paper feed mechanism is set as a detection position, and the transport of the print paper is performed. In a printing apparatus provided with a paper feed sensor for detecting, a discharge conveyance path by the paper discharge mechanism as a detection position, and a paper discharge sensor for detecting conveyance of the printing paper, the paper feed sensor is used in a printing operation process. Calculating the number of paper feeds of the printing paper based on the detection result of the above and the number of paper discharges of the printing paper based on the detection result of the paper discharge sensor, and storing the number of paper supply and the number of paper discharge at the time of completion of the printing operation. And remember At the start of the printing operation, the number of fed sheets and the number of discharged sheets stored in the storage unit are compared to detect a residual error in the apparatus. At the start of the next printing operation, the number of fed sheets and the number of discharged sheets stored in the storage unit are compared at the start of the next printing operation. In order to detect whether or not there is, the conveyance is stopped between the paper feed paper sensor and the paper discharge sensor and to both the non-detection positions. In this state, the power is turned off or the power is turned on. Even when the printing operation is terminated, an in-machine residual error can be detected.

According to a second aspect of the present invention, in the printing apparatus according to the first aspect, at the start of the printing operation, the paper feed paper sensor detects that there is no print paper, and the paper discharge sensor detects that there is no print paper. When the absence of a sheet is detected, the presence or absence of a residual error in the apparatus is checked by the storage means. Since there is no residual error in the apparatus when there is no residual error, the position of the residual error can be recognized.

[Brief description of the drawings]

FIG. 1 shows an embodiment of the present invention and is a schematic configuration diagram of a main part of a stencil printing apparatus.

FIG. 2 is a schematic circuit block diagram of a printing apparatus according to an embodiment of the present invention.

FIG. 3 is a flowchart illustrating a printing operation according to an exemplary embodiment of the present invention.

FIG. 4 is a flowchart illustrating a printing continuation determination according to the embodiment of the present invention.

FIG. 5 is a flowchart illustrating a paper supply / discharge error check according to the embodiment of the present invention.

FIG. 6 is a flowchart illustrating a primary paper jam determination according to an embodiment of the present invention.

FIG. 7 is a flowchart illustrating a printing pressure motor return determination according to the embodiment of the present invention.

FIG. 8 is a flowchart illustrating an operation of pressing the printing pressure motor according to the embodiment of the present invention.

FIG. 9 is a flowchart illustrating a discharge jam determination according to an embodiment of the present invention.

10A and 10B show an embodiment of the present invention, wherein FIG. 10A is a schematic operation flowchart when the power of the printing apparatus is turned on, and FIG. 10B is a flowchart when the power of the printing apparatus is turned off.

FIG. 11 is a flowchart illustrating a remaining sheet check according to the embodiment of the present invention.

FIG. 12 shows one embodiment of the present invention and is a time chart from the start of printing.

FIG. 13 is a schematic diagram of a main part of a conventional printing apparatus.

FIG. 14 is a diagram illustrating positions of a paper feed sensor and a paper discharge sensor and various residual error states.

[Explanation of symbols]

 A paper feed mechanism B printing mechanism C paper discharge mechanism 1 print paper 7 plate cylinder 8 paper cylinder 24 storage means S2 paper feed sensor S3 paper discharge sensor

Claims (2)

[Claims] A paper feed mechanism for transporting a plurality of print papers stacked at a paper feed position one by one to a print mechanism; a print mechanism for performing print processing on the print paper fed by the paper feed mechanism; A paper discharge mechanism for transporting the print paper printed by the print mechanism to a paper discharge position, a paper feed sensor for detecting the paper transport path by the paper feed mechanism as a detection position, and detecting the transport of the print paper; A printing apparatus provided with a paper ejection sensor for detecting the conveyance of the printing paper, wherein the paper ejection conveyance path by the paper ejection mechanism is set as a detection position, and in the printing operation process, the printing is performed based on the detection result of the paper feeding paper sensor. The number of sheets fed and the number of sheets discharged of the printing paper are calculated based on the detection result of the sheet discharge sensor, and the number of sheets fed and the number of sheets discharged at the time of completion of the printing operation are stored in the storage means. Start of printing operation Printing apparatus characterized by detecting a flight residual error by comparing the paper feed quantity and ejected sheets stored in the storage means. 2. The printing apparatus according to claim 1, wherein at the start of the printing operation, the paper feed sensor detects that there is no print paper, and the paper discharge sensor detects that there is no print paper. In some cases, the printing apparatus checks the presence or absence of an in-machine residual error by the storage unit.