JP3287902B2 - Stencil master detection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stencil printing master detecting device for detecting the presence or absence of a stencil printing master.

[0002]

2. Description of the Related Art A stencil printing paper used in a stencil printing machine is composed of a very thin thermoplastic synthetic resin film such as polyester and a synthetic fiber, Japanese paper or Japanese paper as a porous flexible support. And a laminate structure in which synthetic fibers are mixed together. The stencil printing machine performs perforation and stencil making on the heat-sensitive film portion of the base paper by a heating element such as a thermal head, automatically conveys the base paper, and automatically wraps the outer peripheral surface of a porous cylindrical plate cylinder, Pressing means such as a press roller continuously presses the printing paper against the base paper to perform printing by bleeding ink from the opening of the plate cylinder and the perforated part of the base paper.

In such a conventional type of base paper, as a means for confirming the remaining amount at the time of plate making, for example, Japanese Utility Model Publication
As shown in Japanese Patent Publication No. 10055, perforations or cutouts are formed in the base paper wound in a roll at intervals of gradually expanding or reducing, and these indices are determined by using a transmission type photosensor. There is known a technique of detecting a small piece of paper or a printed mark attached to a base paper using a reflective photosensor. Also,
A technology in which a filler-movable sensor connected to and linked with a microswitch is provided on the base paper transport path, and the presence or absence of the base paper is detected by the microswitch being turned on or off when the base paper being transported and moving presses the filler. It has been known.

[0004]

The base paper used for the above-mentioned applications uses Japanese paper or the like as a support. Therefore, when the fibers are present in a portion where Japanese paper fibers are entangled or in a perforated portion, the base paper is used for ink. Passage is hindered, and the ink does not transfer to the printing paper, so that a fiber pattern appears on a solid portion, a fine line portion is cut or faded, and a problem called a so-called fiber mesh occurs. Therefore, an attempt has been made to prevent the generation of fibrous grains by printing with a master (hereinafter, simply referred to as "master") made of only a thermoplastic synthetic resin film without using Japanese paper or the like as a support. ing.

However, when detecting the presence or absence of the above-mentioned master, the former technique uses a transparent film and is very thin, about 2 μm, so that the transmission or reflection type photosensor detects the presence or absence of the master. There is a problem that cannot be done. Also, in the latter technique, even if the master comes into contact with the filler connected / linked with the microswitch, the master itself is deformed because the master itself has no rigidity, so that the desired operation cannot be obtained. There is a problem that cannot be done. Therefore, it is sufficient to increase the apparent strength by increasing the thickness of the film of the master.However, this makes it impossible to perforate the thermal head, or it is necessary to greatly increase the calorific value of the thermal head. There is a problem that the durability is significantly reduced. Actually, even with the film thickness of the conventional base paper, the heat generating element of the thermal head may be punctured due to an excessive amount of heat generated, and it is not preferable to further increase the film thickness. In addition, it is possible to detect the presence or absence of the mark by printing or coloring a transparent master as an object to be detected by conventional detection means, but such processing greatly increases the cost. Problems arise.

SUMMARY OF THE INVENTION Accordingly, the present invention has been made to solve the above-mentioned problems. Accordingly, the present invention provides a stencil printing master detecting apparatus capable of reliably detecting even a transparent and very thin master made of only a thermoplastic synthetic resin film. The purpose is to provide.

[0007]

According to the present invention, in order to achieve the above-mentioned object, an invention according to claim 1 detects the presence or absence of a continuous sheet-shaped stencil master at a predetermined position of a stencil printing apparatus. What is claimed is: 1. A stencil printing master detecting device, comprising: a vent provided at the predetermined position;
With bellows arranged to form an air chamber
Pressure sensor and the pressure sensor are moved toward the vent.
And moving means for moving .

According to a second aspect of the present invention, the presence or absence of a continuous sheet stencil master is provided on a plate cylinder of a stencil printing apparatus.
The stencil printing master tip with the clamper base.
A stencil printing master detecting apparatus for detecting a stencil printing master by a clamper clamped between the clamper base and
At least one pair of electrical contacts provided on the clamper
And an electric circuit formed by being connected to each of the electric contacts.
And a detector provided on the road .

According to the third aspect of the present invention, a substantially transparent heat
Continuous sheet-shaped holes consisting only of a plastic synthetic resin film
A stencil printing master detection device for detecting the presence of a stencil printing master at a predetermined position of a stencil printing device,
Light emission arranged at a predetermined angle across a predetermined position
Element and a light receiving element, the stencil printing at the predetermined position
When there is a master for
The light is refracted by the stencil printing master, and the refracted light is received as described above.
The light emitting element and the light receiving element are received by an optical element.
In this configuration, each child is arranged .

[0010]

[0011]

[0012]

Here, a continuous sheet-shaped stencil master consisting essentially of a thermoplastic synthetic resin film is defined as:
In addition to the one made of the thermoplastic synthetic resin film alone, one or more thin film layers such as an overcoat layer for preventing charging and sticking on at least one of both main surfaces of the thermoplastic synthetic resin film, that is, at least one of the front and back surfaces. A stencil printing master in the form of a continuous sheet, including ones that are adhered. In addition, a continuous sheet-shaped stencil master made of only a substantially transparent thermoplastic synthetic resin film, in addition to the above-described items, is in a transparent state in which the light emitted from the light emitting element can be detected by the light receiving element. That is, a stencil master including a translucent state.

[0014]

According to the first aspect of the present invention, the air chamber is formed.
Pressure sensor with a bellows for
The stencil printing machine
The air trapped in the bellows air chamber is compressed.
This generates air pressure. This air pressure is blocked by the master
A pressure difference is detected by the pressure sensor between a case where the air flow is lost and a case where the air escapes to the air hole without being blocked by the master .

According to the second aspect of the present invention, the clamper
Clamping the master between the clamper base and
That is, when there is a master, the electrical circuit is
Is not clamping the master to the clamper base.
That is, when there is no master, the electrical contacts
The electrical circuit is electrically connected to the
Detected by the detector provided in .

According to the third aspect of the invention , a stencil printing apparatus is provided .
Are arranged at a predetermined angle across the predetermined position of the
There is a master at a predetermined position by light emitting element and light receiving element
Sometimes, the projection light from the light emitting element is refracted by the master and
Is received by the light receiving element. Also, place the marker
When there is no star, the projected light from the light emitting element is not refracted
, And is not detected by the light receiving element .

[0017]

[0018]

[0019]

[0020]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. Note that the thickness of the stencil master 1 shown in the accompanying drawings is exaggerated and enlarged to clarify the configuration of the detection device.

FIG. 1 shows an embodiment of the present invention. In FIG. 1, reference numeral 1 denotes a stencil printing master (hereinafter simply referred to as “master”). The master 1 is formed in a continuous sheet shape consisting essentially of a substantially transparent thermoplastic synthetic resin film, and is wound and rotated as a master roll (not shown). The thermoplastic synthetic resin film of the master 1 is formed with a very thin thickness of about 2 μm, and is made of, for example, polyester and has electrical insulation.

A pair of upper and lower forward rollers for transporting the master 1 is provided in a master transport path P for transporting the master 1 from a master roll (not shown) via a platen roller and a thermal head (both not shown). The pairs 2a and 2b are provided so as to be pressed against each other and rotatable in the direction of the arrow. In addition, the master 1 transported from the forward feed roller pair 2a, 2b is provided in the master transport path P downstream of the forward feed roller pair 2a, 2b.
Roller pair 3a, 3
b are provided so as to be pressed against each other and rotatable in the direction of the arrow. Forward feed roller pair 2a, 2b and backward feed roller pair 3
a and 3b are driven to rotate by a step motor (not shown). Above the forward feed roller 2a, a blower pump 4 for forming a blower a as a blower is attached to a stationary member (not shown) of the stencil printing apparatus. One end of a blower pipe 5 constituting a blower is connected to the blower pump 4, and a blower outlet 6 for discharging blower a is formed at the other end of the blower pipe 5. The blower pipe 5 is bent in an inverted L-shape, and its blower port 6 is piped facing the master transport path P. Below the air outlet 6 of the air blow pipe 5, a pressure sensor 7 is attached to a stationary member (not shown) opposite to the air outlet 6 with the master transport path P interposed therebetween. The pressure sensor 7 is, for example, a sensor having a strain gauge or a known sensor having a piezoelectric element.
Reference numeral 8 denotes a lead wire of the pressure sensor 7.

As described above, the detection device 10 for the master 1 shown in FIG. 1 includes the air supply pump 4 and the air supply pipe 5 serving as air supply means, which are disposed opposite to each other on the master transport path P. Pressure sensor 7 for detecting the wind pressure of the means
It is composed of

Next, the operation of the detecting device 10 of the master 1 will be described. The master 1 conveyed in the direction of the arrow from the upstream side of the master conveying path P is moved downstream by the forward feed roller pair 2a, 2b and the rear feed roller pair 3a, 3b rotating in the direction of the arrow. Transported to At this time, the blower pump 4 is driven by a control signal from a control device (not shown), and the blower a discharged from the blower pump 4 is discharged from the blower port 6 of the blower pipe 5, but the blower a is blocked by the master 1. Therefore, the air pressure is not detected by the pressure sensor 7, and the detection signal is input to a control device (not shown). A control device (not shown) detects a detection signal that is blocked by the master 1 and a detection signal that is not blocked by the master 1, that is, a pressure difference between an air pressure when blocked by the master 1 and an air pressure when not blocked by the master 1. And the presence of the master 1 is detected.

FIG. 2 shows another embodiment of the present invention. In FIG. 2, reference numeral 21 denotes a plate cylinder. The plate cylinder 21 has a well-known porous cylindrical configuration, and is rotatably disposed at a predetermined portion of the stencil printing apparatus. At a predetermined position on the outer peripheral surface of the plate cylinder 21, a ventilation hole 22 larger than a porous hole (not shown) is formed so as to penetrate through the inside of the plate cylinder 21. It is wound. A pressure sensor 7 having a bellows 23 for forming an air chamber is provided near the outside of the ventilation hole 22 of the plate cylinder 21 with its bellows opening 24 facing the ventilation hole 22. The pressure sensor 7 and the bellows 23 are fixedly supported by moving means (not shown), and are arranged so as to be able to move up and down in the direction of the arrow by a moving means (not shown). The moving means (not shown) includes, for example, a combination mechanism of a drive source of a motor or a solenoid and a cam or a link mechanism.

As described above, the detecting device 20 of the master 1 shown in FIG.
2 and the air holes 22, respectively.
Pressure sensor 7 having bellows 23 for forming air chamber
And a moving means (not shown) for moving the pressure sensor 7 toward the ventilation hole 22.

Next, the operation of the detecting device 20 of the master 1 will be described. The pressure sensor 7 having the bellows 23 is moved down by the moving means (not shown) to the ventilation hole 22 provided at a predetermined position of the plate cylinder 21 of the stencil printing apparatus, and the bellows opening 24 of the bellows 23 is indicated by a virtual line in the figure. When the bellows 23 is in close contact with the surface of the master 1 as described above, the air trapped in the air chamber is compressed by the compression of the bellows 23 to generate air pressure.
As shown in FIG.
The pressure sensor 7 detects a pressure difference between each air pressure and a case where the air escapes to the vent hole 22 without being interrupted by the air pressure (not shown).

FIG. 3 shows a modified embodiment of the detecting device 20. The detection device 20A of the master 1 compresses the bellows 23 with the bellows opening 24 of the bellows 23 close to the ventilation hole 22 inside the plate cylinder 21 with respect to the detection device 20, and then not shown. By the moving means, the ventilation holes 22
Only when the pressure sensor 7 detects the pressure difference of each air pressure between the case where it is separated by the master 1 on the suction side and the case where the vent hole 22 is open to the atmosphere without being blocked by the master 1. Different.

According to the detectors 20 and 20A, there is no need to provide a blower for the blower pump 4 and the blower pipe 5 so as to face the pressure sensor 7, so that the apparatus can be simplified and inexpensive.

FIG. 4 shows another embodiment of the present invention. In FIG. 4, reference numeral 30 denotes a detection device of the master 1. The detecting device 30 includes a pair of conductive rollers 31a and 31b, which are pressed against each other with the master transport path P interposed therebetween and are rotatably disposed in the direction of the arrow, and these conductive rollers 31a and 3b.
1b connected to the respective electric circuits 32, 3
3 and a detector 34 for detecting the presence or absence of conduction between the electric circuit 32 and the electric circuit 33. Reference numeral 35 denotes a resistor, reference numeral 36 denotes a power supply, and reference numeral 37 denotes a power supply.
Indicates grounding of the electric circuits 32 and 33, respectively.

The conductive roller of the detecting device 30 is not limited to the above embodiment. For example, in the case where a plurality of rollers which are pressed against each other vertically are arranged in a skewered shape, the upper and lower
It is only necessary that the pair of rollers be made of a conductor. Further, the conductor does not need to be made entirely of a conductor, and for example, only a specific portion around the rollers that are in pressure contact with each other may be made of a stripe-shaped conductor.

According to the detecting device 30, the presence or absence of the master 1 can be detected and the conductive rollers 31a, 31a can be detected.
The master 1 can be transported by b.

FIG. 5 shows still another embodiment of the present invention.
In FIG. 5, reference numeral 41 denotes a clamper pedestal. The clamper pedestal 41 extends in a part of the outer peripheral surface of the plate cylinder (not shown) in the direction of the axis (not shown) of the plate cylinder, and is provided in a non-print image area of the plate cylinder (not shown). The clamper 42
A fulcrum shaft 43, which extends in the direction of the plate cylinder axis (not shown) and is supported on the clamper pedestal 41, is provided on a part of the outer peripheral surface of the plate cylinder (not shown) so as to be openable and closable as a pivot point. ing. The clamper 42 includes a clamper plate 49 and a clamper plate 4.
9 and a rubber magnet 44 attached to the lower part. A rubber magnet base 45 as a clamper base is mounted on the clamper pedestal 41 so as to face the rubber magnet 44, and a conductive base formed by printing or plating at a substantially central portion of the rubber magnet base 45. An electrically insulating flexible printed board 46 having a contact 47 and a clamper contact 48 (shown by hatching obliquely upward to the right in the figure) is arranged. With the above configuration, the tip of the master 1 is clamped between the rubber magnet base 45 as the clamper base and the rubber magnet 44 of the clamper 42. The base contact 47 and the clamper contact 48 as electric contacts are separated from each other on the clamper pedestal 41 with a substantially central portion of the flexible printed board 46 as a boundary, and the base contact 47 is a rubber magnet base 45 in the drawing. An inverted L-shape is formed on the left side, and the clamper contact 48 is disposed on the rubber magnet base 45 from the right side in the drawing of the rubber magnet base 45.
4 are provided to extend to the vicinity of the lower left end. The base contact 47 is connected to an electric circuit 33 similar to that shown in FIG. 4 and the clamper contact 48 is connected to an electric circuit 32 having a detector 34 similar to that shown in FIG. The clamper contacts 48 are arranged at positions where they contact each other when the clamper 42 is closed without the master 1.

As described above, the detection device 40 of the master 1 shown in FIG. 5 uses the rubber magnet base 4 as a clamper base.
5 and at least one pair of electrical contacts provided on the rubber magnet 44 of the clamper 42, a base contact 47 and a clamper contact 48, and an electric circuit 32 formed by being connected to the base contact 47 and the clamper contact 48, respectively. , 33 (shown in FIG. 4 and not shown in FIG. 4) and a detector 34 (shown in FIG. 4 and not shown in FIG. 4).

Next, the operation of the detecting device 40 of the master 1 will be described. The clamper 42 clamps the master 1 between itself and the rubber magnet base 45 as a clamper base. That is, when the master 1 is present, the base contact 47 and the clamper contact 48 do not come into contact with each other, and an electric circuit (not shown) is not provided. The electric circuit (not shown) is formed by the fact that the clamper 42 does not clamp the master 1 between the rubber magnet bases 45 serving as the clamper base, that is, the base contact 47 and the clamper contact 48 contact each other when the master 1 is not present. It is conducted and detected by detectors provided in an electric circuit (not shown). According to the detecting device 40, the presence or absence of the master 1 can be detected, and the fact that the leading end of the master 1 has been conveyed to the clamping portion of the clamper 42 can also be reliably detected. Further, when the leading end of the master 1 is not conveyed to the holding portion of the clamper 42, for example, rotation of a plate cylinder (not shown) may not be performed.

FIG. 6 shows still another embodiment of the present invention.
The detection device 50 of the master 1 has a light emitting element 51 and a light receiving element 52 arranged at a predetermined angle with respect to the master transport path P, and a pair of upper and lower feed rollers 53 and 54 are provided on the master transport path P. When the master 1 is transported from the upstream side to the downstream side in the direction of the arrow, that is, when the master 1 is at a predetermined position on the master transport path P, the projection light Lp from the light emitting element 51 is substantially applied to the master 1 surface. The light-emitting element 51 and the light-receiving element 52 are arranged so that the light is totally reflected and the substantially total reflected light Lr is received by the light-receiving element 52. The light emitting element 51 and the light receiving element 52 are, for example, well-known solid state optical sensors including photodiodes. Here, substantially total reflection means
It refers to substantially total reflected light Lr that can be detected by the light receiving element 52, and there may be a little transmitted light in this range. That is, the light emitting element 51 and the light receiving element 52 may be arranged at a predetermined angle having a certain range with respect to the master transport path P. Reference numerals 51a and 51b denote the light emitting elements 51, 52a and 52, respectively.
b indicates a signal line of the light receiving element 52, respectively.

The operation of the detecting device 50 of the master 1 will be briefly described. When the master 1 is conveyed from the upstream side to the downstream side in the direction of the arrow by the pair of upper and lower feed rollers 53 and 54 in the master conveying path P, the light emission arranged at a predetermined angle with respect to the master conveying path P, respectively. The projection light Lp from the light emitting element 51 is substantially totally reflected by the surface of the master 1 by the element 51 and the light receiving element 52, and the substantially total reflected light Lr is received by the light receiving element 52 and converted into a light receiving voltage. The light receiving voltage of the light receiving element 52 is input to a control device (not shown), and is compared with the voltage of the light receiving element 52 when there is no master 1 on the master transport path P, and the presence or absence of the master 1 is detected.

FIG. 7 shows a modified embodiment of the detection device 50.
The detection device 50 of the master 1 shown in this modified embodiment
A differs from the detection device 50 in the points described below. In FIG. 7, reference numeral 21A denotes a single cylinder type plate cylinder.
The plate cylinder 21A is provided with a slit 59 for preventing irregular reflection of light, instead of the ventilation hole 22 formed at a predetermined position on the outer peripheral surface of the plate cylinder 21 shown in FIGS. The only difference. In the vicinity of the outside of the slit 59 provided in the plate cylinder 21A, the light emitting element 51 and the light receiving element 52 substantially totally reflect the projection light Lp from the light emitting element 51 on the master 1 surface located on the slit 59. The stencil printing apparatus is provided on a stationary member (not shown) so that the light receiving element 52 receives the substantially total reflected light Lr. Therefore, when the master 1 is not clamped by the clamper 42A and is not on the plate cylinder 21A, the projection light Lp projected from the light emitting element 51 passes through the slit 59 without being reflected by the outer peripheral surface of the plate cylinder 21A. 21
A will be introduced.

Inside the plate cylinder 21A, an ink roller 55 for supplying ink to the inner peripheral surface of the plate cylinder 21A is disposed in parallel with the ink roller 55 with a small gap. And a doctor roller 57 for forming a wedge-shaped ink reservoir 56, and an ink pipe 58 which also serves as a rotation center axis of the plate cylinder 21A and supplies ink to the ink reservoir 56. The inside of the plate cylinder 21A has a known structure. Make Here, the ink pipe 58, the ink roller 55, and the doctor roller 57 constitute a printing ink supply device. Reference numeral 42A denotes an openable and closable clamper that extends in the axial direction on a part of the outer peripheral surface of the plate cylinder 2 and holds the leading end of the plate-making master 1.

FIG. 8 shows a modified embodiment of the detecting device 50.
The detection device 50B of the master 1 is different from the detection device 50 in that the master 1
When the master 1 is conveyed from the upstream side in the direction of the arrow by 3, 54, that is, when the master 1 is at a predetermined position, the projection light Lp from the light emitting element 51 is refracted by the master 1 and the refracted light Ld is received by the light receiving element. The difference is that the light emitting element 51 and the light receiving element 52 are arranged at a predetermined angle with the master transport path P interposed therebetween so that the light is received by the light receiving element 52. According to the detection device 50B of the master 1, in the case of the total reflection light Lr in the detection device 50, the light emitting element 51
In order to prevent malfunction on the light receiving element 52 side, it is necessary to narrow the optical axis and to increase the distance between the two elements. The device itself can be made compact because it is not necessary to make the device as large as the former.

The detecting devices 10, 20, 20A of the master 1
30, 40, 50, 50 A, 50 B are not limited to a specific position or a specific portion of the stencil printing apparatus of the above-described embodiment, and are preferably in a predetermined position such as a master transport path or a master guide plate. It goes without saying that it can be applied.

Detection devices 10, 20, 20A, 30, 40
Can detect the presence or absence of a conventional stencil sheet.

[0043]

As described above, according to the present invention, even if the master is made of only a transparent and very thin thermoplastic synthetic resin film, the master can be reliably detected at each predetermined position. .

[Brief description of the drawings]

FIG. 1 is a side view of a main part of a stencil printing master detecting apparatus according to an embodiment of the present invention.

FIG. 2 is a side view of a main part of a stencil printing master detecting apparatus according to another embodiment of the present invention.

FIG. 3 is a side view of a main part of a stencil printing master detecting apparatus showing a modified embodiment of FIG. 2;

FIG. 4 is a side view of a main part of a stencil master detecting device showing still another embodiment of the present invention.

FIG. 5 is a cross-sectional view of a main part of a stencil printing master detecting apparatus showing a modified example of FIG. 4;

FIG. 6 is a side view of a main part of a stencil master detecting device according to still another embodiment of the present invention.

FIG. 7 is a side view of a main part of a stencil printing master detecting apparatus showing a modified embodiment of FIG. 6;

FIG. 8 is a side view of a main part of a stencil printing master detecting apparatus showing a modified embodiment of FIG. 6;

[Explanation of symbols]

Lp Projection light Ld Refraction light Lr Substantially total reflection light P Master transport path 1 Master for stencil printing substantially composed of only thermoplastic synthetic resin film 4 Ventilation pump as ventilation means 5 Ventilation pipe as ventilation means 7 Pressure sensor 10, 20, 20A, 30, 40, 50, 50A, 50
B Master detecting device 21, 21A plate cylinder 22 vent hole 23 bellows 31a, 31b conductive roller pair 32, 33 electric circuit 34 detector 42 clamper 45 rubber magnet base as clamper base 47 base contact as electric contact 48 as electric contact Clamper contact 51 light emitting element 52 light receiving element 59 slit

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B41L 13/14 B41F 27/12 B41J 13/00

Claims (3)

(57) [Claims] 1. A stencil printing master detection device for detecting the presence or absence of a continuous sheet stencil printing master at a predetermined position of a stencil printing device, comprising: a ventilation hole provided at the predetermined position; Facing
Pressure with bellows to form an air chamber
A force sensor and the pressure sensor are moved toward the vent.
A stencil printing master detecting device, comprising: 2. A stencil printing master provided on a plate cylinder of a stencil printing machine, the presence or absence of a continuous sheet stencil master.
To clamp the tip of the
A detecting apparatus of the stencil printing master which detects the damper, less provided on the clamper base and said clamper
At least one pair of electrical contacts
And a detector provided in an electric circuit formed in succession . 3. A substantially transparent thermoplastic synthetic resin film.
The presence or absence of a continuous sheet stencil master consisting of
A stencil printing master detection device for detecting a stencil printing device at a predetermined position, wherein the stencil printing master detection device is disposed at a predetermined angle across the predetermined position.
A stencil having a light emitting element and a light receiving element,
When there is a printing master, the projection light from the light emitting element
Is refracted by the stencil master, and the refracted light is
The light emitting element and the light receiving element are received by the light receiving element.
An apparatus for detecting a stencil printing master, wherein an optical element is arranged .