JPH0632037A - Contamination preventive device of press roller of stencil printing machine - Google Patents

Abstract

PURPOSE:To eliminate back contamination of a blank form ascribable to contamination of a press roller, by providing a device wherein detected information and top and bottom movement information are applied to the same, operated and existence of projection of an image in a top and bottom direction to a printing form is discriminated. CONSTITUTION:The size of a printing form is detected by a printing form size detecting sensor 25 provided on a paper feeding rest 21, data of which is applied to a control device and kept as a memory. Then the same is compared with image positional data and operated, through which a relation between the printing form 11 and an image position is discriminated. The data of the size of the printing form 11 is converted into the pulse-frequency within the control device so that the data becomes comparable with the other image positional data and recorded as the size of the form. Then a movement direction and movement quantity are applied to the control device by operation of a top and botton movement key, converted into the pulse- frequency and recorded as a top and botton movement quantity. Then in accordance with a pre-established program, compared with the other image information, operated and existence of projection of the image is decided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a press roller for a stencil printing machine, which prevents stains on the press roller due to an image protruding from the printing paper when the printing paper of the stencil printing apparatus integrated with plate making and printing is moved in the vertical direction. A stain prevention device.

[0002]

2. Description of the Related Art A conventional stencil printing machine 1 for plate making and printing
For the most part is the same as the embodiment of the present invention,
This will be described with reference to FIG. It has a document feeder 27,
An operation unit (not shown), a document image reading unit 4, a plate making apparatus 6 for punching and making a plate, a stencil sheet storage unit 7, and a printing drum adapted to clamp and wind the tip of the stencil sheet 7 around the outer periphery. 9, a press roller 10 in pressure contact with the printing drum 9, a vertical movement device (not shown) for the printing paper 11, a paper feeding device 18, a paper ejection device 19, a plate ejection device 20, an original paper 2, a stencil paper 7, The operation unit is provided with a display device, a vertical movement key, a ten-key pad, a print start key, and the like. Document feeder 27
Conveys the original sheet 2 to the image reading section 4 of the original by a pair of upstream original conveying rollers 12 and 13 provided on the upstream side in the conveying direction of the original sheet 2. The original image is mirror 29 and lens 30
The image is optically made incident on the image sensor 5 such as CCD via the, and read, and the electric signal photoelectrically converted by the image sensor 5 is mounted on a circuit board (not shown) provided in the main body cabinet 3. It is input to the A / D conversion circuit and output as a digital image signal. In synchronism with the image reading operation, while carrying the stencil sheet 7 drawn out from the stencil sheet storage section 7 for storing the roll stencil sheet 7, the thermal head 17 punches the stencil sheet 7 in response to the image signal, A stencil sheet 7 is cut to a predetermined size with a cutter device for cutting, the stencil sheet 7 is mounted on the print drum 9 on the outer periphery, the print drum 9 is rotated, and the print sheet 11 is fed from the sheet feed table 21 at a predetermined timing. The press roller 10 presses the stencil sheet 7 on the outer peripheral surface of the printing drum 9 so that the printing ink supplied from the inside of the printing drum 9 is transferred from the perforations of the stencil sheet 7 to the surface of the printing paper 11, so-called trial. Perform printing, check the print status, set the number of prints with the numeric keypad, and turn on the print start key.The paper feed, print, and discharge processes are repeated for the number of prints set. It is for printing.

When it is necessary to correct the image position in the vertical direction in the trial printing process or the like, the operator inputs the moving direction and the moving amount with the vertical moving key, and the sheet feeding cam of a sheet feeding device (not shown). Alternatively, the paper feed control device that controls the drive of the paper feed motor adjusts the timing of starting the paper feed and moves the printing paper 11 relative to the stencil sheet 7 to move the image position. ing.
Reference numerals 14 and 15 denote pairs of downstream document transport rollers, 16 denotes a separation roller, 28 denotes a light source, and 31 denotes a contact glass.

[0004]

In the conventional plate-making / printing integrated stencil printing apparatus as described above, when the printing paper is moved in the vertical direction by the up / down movement key, if the printing paper is moved too much, the printing paper There is a problem in that the leading edge or the trailing edge of the image sticks out to stain the press roller and stain the back of the printing paper.

Therefore, an object of the present invention is to control the printing paper so that the leading edge or the trailing edge of the image does not stick out when the printing paper is moved in the vertical direction by the up / down moving key.
An object of the present invention is to provide a stencil printing apparatus of integrated plate making and printing in which the press roller is prevented from becoming dirty and the backside of the printing paper is not generated.

[0006]

In order to achieve the above-mentioned object, the present invention provides a plate making apparatus for carrying out at least a document feeding device, a document image reading device, and a perforation plate making. In a stencil printer integrated with plate making and printing, which has a printing drum adapted to clamp and wind the leading end of the stencil sheet around the outer periphery, a press roller that presses against the printing drum, and an up-and-down moving device for the printing paper. A document detecting unit is provided in the vicinity of the image reading unit, a document conveying distance detecting unit is provided in the document conveying device, and a print sheet size detecting unit is provided in the paper feed table. From these, the document size, the print sheet size, and the position of the image are provided. Is provided, and the detection information and top-and-bottom movement information are input, arithmetic operations are performed, and an image protrusion detection device that determines whether or not the image in the top-bottom direction is protruded from the printing paper is provided. Than it is. According to a second aspect of the present invention, in the first aspect of the invention, when the image protrusion detecting device detects that the image position is protruding from the print sheet, it is provided with means for notifying the fact. According to a third aspect of the present invention, in the first aspect of the invention, when the image protrusion detection device detects the protrusion of the printing paper at the image position, it does not accept the up-and-down movement command signal or does not start printing. It is equipped with means for controlling. According to a fourth aspect of the present invention, in the first aspect of the present invention, a display device for displaying the position of the image with respect to the printing paper detected by the image protrusion detection device as a numerical value or a figure is provided.

[0007]

In the invention as described above, the invention of claim 1 is, in the plate making / printing integrated stencil printing machine as described above, a document detecting means in the vicinity of the image reading means and a document conveying distance to the document conveying device. A detection unit and a printing paper size detection unit are provided on the paper feed table, the document size, the printing paper size, and the position of the image are detected from them, and the detection information and the vertical movement information are input, An image protrusion detecting device for calculating whether or not the image in the top-bottom direction is projected on the printing paper is provided, and the presence or absence of the protrusion of the image in the top-bottom direction on the printing paper is detected. According to a second aspect of the present invention, in the first aspect of the invention, when the image protrusion detecting device detects that the image position is protruding with respect to the printing paper, the image protrusion detecting device is provided with a means for notifying the protrusion, Notify the operator of the image protrusion. According to a third aspect of the present invention, in the first aspect of the invention, when the image protrusion detection device detects the protrusion of the printing paper at the image position, it does not accept the up-and-down movement command signal or does not start printing. When the image in the top-bottom direction on the printing paper protrudes, the top-bottom movement command signal is not accepted or printing is not started. According to a fourth aspect of the present invention, in the first aspect of the present invention, a display device for displaying the position of the image on the printing paper detected by the image protrusion detection device in the form of a numerical value or a figure is provided. Is displayed on the display device.

[0008]

Embodiments of the present invention will be described below with reference to the accompanying drawings. In this embodiment shown in the drawings, the same parts as those of the conventional one are referred to by the same reference numerals, and the description thereof will be omitted.

A first embodiment of the present invention is shown in FIGS.
Since the first embodiment of the present invention shown in the figure and other embodiments other than the above are common in many parts, the same reference numerals as those in the first embodiment are used for these parts and the description thereof is omitted. Will be omitted and mainly different parts will be described.

In FIGS. 1 and 2 showing the first embodiment, the document detection sensor 22 is provided between the contact glass 31 and the upstream document transport roller 12. Document detection sensor
Although the optical sensor with a filler is used for 22, the other type of optical sensor such as a reflective optical sensor may be used as long as it can reliably detect the original. A disc 23 with a slit is directly attached to the shaft of the upstream-side transport roller 12 so as to interlock with the upstream-side document transport roller 12. A rotation detection sensor 24 that detects the rotation of the circular disc 23 with slits is provided in a non-contact manner with the circular disc 23 with slits, and the circular disc 23 with slits and the rotation detection sensor 24 detect the amount of rotation of the upstream document transport roller 12. Then, the feed amount of the document sheet 2 is detected. The slitted disc 23 need not be directly attached to the shaft of the upstream-side document conveying roller 12, but an indirect interlocking mechanism may be used as long as its rotation amount can be detected.
The rotation detection sensor 24 is for detecting the slit of the slitted disc 23, and is used as a transmissive optical sensor, but when a disc containing magnetic information is used instead of the slitted disc 23. May use a magnetic sensor to detect it. A paper size detection sensor 25 is provided on the paper feed table 21. The printing paper size detection sensor 25 is for detecting the size of the printing paper, and uses a plurality of filler type detection sensors. Not limited to these, a light reflection type sensor or a line sensor may be used.

The control device 26 shown in FIG. 3 includes a CPU 33 and an R
A stencil printing machine 1 including an OM34 and a RAM35
The document detection sensor 22, the rotation detection sensor 24, the image sensor 5, the printing paper size detection sensor 25, and the up-and-down movement key 32 provided on the operation panel 36 are connected inside the document detection sensor 22, the rotation detection sensor 24, the image sensor 5, and the up-and-down movement key 32. Input the output of CPU33
Performs arithmetic processing according to a preset program, and performs display output to a display device 38 provided on the operation panel 36 and output for drive control of the upside-down movement drive device 37.

In this embodiment, the manuscript paper 2 is set on a manuscript tray (not shown) of the image reading unit 4, and a plate making start key (not shown) is turned on. The separation roller 16 of the image reading unit 4 and the upstream manuscript conveying roller 12 are turned on. , 13 and the downstream side document transport rollers 14, 15 are rotated, the document sheet 2 is transported, and the document detection sensor 22 and the rotation detection sensor 24
And the image sensor 5 generate outputs, which are input to the CPU 33 to start calculation of the image position of the document. The analog output of the image sensor 5 is digitized by the A / D conversion board.

In FIG. 4, which shows a timing chart for detecting the document image position, the controller 26 controls the slitted disc 23 from the time when the output of the document detection sensor 22 detects the leading edge of the document sheet 2 and turns on. The number of slits is counted by the output of the rotation detection sensor 24, the digital output of the image sensor 5 is monitored at the same time, and the count number of the rotation detection sensor 24 until the time when the output is first turned on is shown in FIG. , 6 are stored in the control device 26 as the front end margin b of the original paper 2. Next, the counting is started again from that point, the count number from the time when the output of the image sensor 5 is turned on to the time when it is turned off is temporarily stored in the control device 26, and the operation is detected by the output of the document detection sensor 22 at the end of the document. The control device continues to store until it is detected and the output is turned off, and the count number until the output of the image sensor 5 is turned off at the end of the image is set as the image range c.
Store in memory at 26. Further, if the count number of the rotation detection sensor 24 while the document detection sensor 22 is on is stored in the control device 26 as the document size a, the CPU
33 calculates the document image position according to a preset program.

Plate making is performed in synchronization with the image reading operation,
The printing paper 11 loaded on the paper feed table 21 is fed at the same time when the plate feeding is completed on the printing drum 9, and the printing paper size detection sensor 25 is provided on the paper feed table 21. By detecting the size of the printing paper by means of this, inputting this data to the control device 26 and storing it in memory, and comparing it with the image position data, the relationship between the printing paper 11 and the image position can be known. The size data of the printing paper 11 is converted into the number of pulses in the control unit 26 so that it can be compared with other image position data, and is stored as the printing paper size d. Next, in order to move the image position to an arbitrary position, by operating the up-and-down movement key 32, the movement direction and movement amount are input to the control device 26 and converted into the pulse number like other data, and the up-and-down movement amount is changed. It is possible to determine whether or not the image has overflowed by storing it as e and performing a comparison operation with other image information by a preset program. It is, for example,
By inputting the vertical movement information from the vertical movement key 32, FIG.
As shown in FIG. 5, if the paper feed timing of the print paper 11 is delayed (-e) and moved, the leading edge margin h1 of the print paper 11
Is the image leading edge margin b + (− e), and the trailing edge margin i1 of the printing paper 11 is the sheet size d− (leading edge margin b + image range c) + (− e). If the values of both the leading edge margin h1 and the trailing edge margin i1 are positive, there is no protrusion of the image, and if either of them is negative, the image is protrusion, and whether the image is displayed on the display device 38 is displayed. Or, an acoustic warning sound is emitted to notify the operator of the abnormality, and the backside of the paper is prevented from becoming dirty due to dirt on the press roller. Next, when the second vertical movement command is issued from this state, the value of the leading edge margin b of the original sheet 2 is set to the leading edge margin h1 of the printing sheet 11.
If the memory data in the control device 26 is replaced and the paper feed timing is advanced (+ e) as shown in FIG. 6, for example, the leading edge margin h2 of the printing paper after the second movement is the first time. Print paper leading edge margin h1 + (+
e), and the trailing edge margin i2 of the second sheet is the printing sheet size d− (first sheet leading edge margin h1 + image range c).
It becomes + (+ e). Here, as in the case of the first time, if the positive and negative of the second-time printing paper leading edge margin h2 and the second-time printing paper rear edge margin i2 are determined, it is possible to know whether or not the image has overflowed. The value of the sheet leading edge margin h1 is replaced with the second sheet leading edge margin h2, and the protrusion of the image can be determined no matter how many times the top and bottom are moved.

When it is determined that the image has overflowed on the printing paper 11 and it is determined that the image has overflowed, the control unit 25 causes an error such as "the image overflows from the paper" by the signal from the control panel display device. The display output is output to 38, or the buzzer is controlled to acoustically sound a warning sound.

In the second embodiment of the present invention, not only is the sign of the leading edge margin h of the printing sheet and the trailing edge margin i of the printing sheet determined, but the numerical value is converted into a distance to determine the position of the image and the printing sheet 11. As can be seen, there is no difference from the first embodiment except that a display is displayed on the display device 38 with a picture or a numerical value so that the top and bottom can be easily moved without making a test print.

According to the third embodiment of the present invention, a signal for image protrusion is input to the up-and-down movement processing circuit to activate the up-and-down movement input elimination circuit to prevent the up-and-down movement input from being input, and the printing drive is started. There is no difference from the first embodiment except that the drive output control circuit is controlled so as not to stop the print start drive.

The present invention can be used to prevent image stains when moving upside down in a digital printing apparatus, a digital copying machine or the like other than the above.

[0019]

The present invention is as described above, and the invention of claim 1 is, at least, a document feeding device, a document image reading means, a plate making device, a printing drum, and a press for press-contacting the printing drum. In a stencil printer integrated with plate making and printing, which has a roller and an up-and-down moving device for printing paper, a document detecting unit near the image reading unit, a document conveying distance detecting unit at the document conveying device, and a printing sheet at a paper feed table. A size detecting unit is provided, and the document size, the print paper size, and the position of the image are detected from them, and the detection information and the vertical movement information are input and calculated, and the image in the vertical direction with respect to the printing paper is calculated. It has an image protrusion detection device that determines the presence or absence of protrusion, and it detects the presence or absence of protrusion of the image in the top-bottom direction on the printing paper, so that the image does not protrude from the printing paper. Te, there is an effect that it is possible to prevent the occurrence of printing paper backside contamination due to contamination of the press roller. According to a second aspect of the invention, in the first aspect of the invention, when the image protrusion detecting device detects that the image position is protruding from the printing paper, the image protrusion detecting device is provided with a means for notifying the fact. Since the operator is notified of the protrusion of the image in the direction, the operator can easily judge the protrusion of the image and prevent the image from protruding from the printing paper, and prevent the occurrence of stains on the back of the printing paper due to stains on the press roller. There is an effect that can be. According to a third aspect of the present invention, in the first aspect of the invention, when the image protrusion detection device detects the protrusion of the printing paper at the image position, it does not accept the up-and-down movement command signal or does not start printing. Since it is equipped with a means to control, the image can only move up and down to the position where it does not stick out from the printing paper, and the press roller becomes dirty due to the image sticking out without the operator having to bother. There is an effect that it is possible to prevent the occurrence of stains on the back of the printing paper without causing the occurrence. According to a fourth aspect of the present invention, in the first aspect of the present invention, a display device for displaying the position of the image on the printing paper detected by the image protrusion detection device in the form of a numerical value or a figure is provided. Since it is displayed on the display device, the operator can easily know the image position by looking at the display part, and to confirm the image position after moving up and down, without touching the test print one by one, There is an effect that a desired printed matter can be easily obtained without causing stains on the back of the printing paper.

[Brief description of drawings]

FIG. 1 is a schematic vertical sectional view showing a first embodiment of the present invention.

FIG. 2 is a perspective view showing an attachment state of the above-mentioned slitted disk and a rotation detection sensor.

FIG. 3 is a connection diagram of the configuration block of the above control device, an operation panel, a rotation detection sensor, a document detection sensor, an image sensor, a printing paper detection sensor, and an up-and-down movement drive device.

FIG. 4 is a diagram showing a timing chart for detecting the document image position in the above.

FIG. 5 is an explanatory diagram showing a state in which the printing paper feed timing is moved with a delay.

FIG. 6 is an explanatory diagram showing a state in which the printing paper is moved earlier by advancing the paper feed timing.

[Explanation of symbols] 1 stencil printer 2 original paper 3 main body cabinet 4 image reading section 5 image sensor 6 plate making device 7 stencil base paper 8 stencil base storage section 9 printing drum 10 press roller 11 printing paper 12, 13 upstream side document conveying roller 14, 15 Downstream document transport roller 16 Separation roller 17 Thermal head 18 Paper feed device 19 Paper ejection device 20 Plate ejection device 21 Paper feed table 22 Document detection sensor 23 Disc with slit 24 Rotation detection sensor 25 Printing paper size detection sensor 26 Control Device 27 Original transport device 28 Light source 29 Mirror 30 Lens 31 Contact glass 32 Vertical movement key 33 CPU 34 ROM 35 RAM 36 Operation panel 37 Vertical movement drive device 38 Display device

Claims (4)

[Claims] 1. A document transporting device, a document image reading means, a plate-making device for punching a plate, a printing drum adapted to clamp and wind the front end of a stencil sheet around an outer periphery thereof, and a printing drum. In a stencil printer with integrated plate making and printing, which has a press roller that presses against a sheet and a vertical movement device for printing paper, a document detecting unit near the image reading unit, a document conveying distance detecting unit at the document conveying unit, and a paper feeding unit. A printing paper size detecting means is provided on the stand, and the document size, the printing paper size, and the position of the image are detected from them, and the detection information and the vertical movement information are input and calculated to calculate the printing paper size. A press roller stain prevention device for a stencil printing machine, comprising an image protrusion detection device for determining whether or not an image in the top-bottom direction is protruding. 2. The press roller stain prevention device for a stencil printing machine according to claim 1, wherein the image protrusion detection device is provided with means for notifying that the image position has protruded from the printing paper. . 3. An image protrusion detecting device is provided with a means for controlling so as not to accept a vertical movement command signal or to start printing when an image position of a print sheet is detected as a protrusion. A press roller stain prevention device for a stencil printing machine according to item 1. 4. The press roller stain prevention device for a stencil printing machine according to claim 1, further comprising a display device for displaying the position of the image on the printing paper detected by the image protrusion detection device as a numerical value or a figure.