JPH0715340U - Screen printing machine - Google Patents

Abstract

(57) [Summary] [Purpose] To prevent ink dripping from the squeegee on the screen plate surface during ink leveling, to ensure printing without bleeding, and to improve product yield. [Structure] A squeegee 10 arranged in the front and rear in the running direction and a scoop-shaped doctor 20 are turned upside down with each other as the squeegee 10 moves forward and backward in the running direction, and a screen printing on which ink K is applied is lowered by the squeegee 10. Printing is performed by pressing the plate S against the surface of the printing material and rubbing it, and the ink is leveled by the lowered doctor 20. At the time of ink leveling, the ink receiving portion 20C of the doctor 20 is arranged immediately below the rising squeegee 10 so as to receive the ink K dropped from the squeegee 10.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention performs printing by pressing a screen printing plate coated with ink with a squeegee on the surface of the printing material and rubbing it to print, and in order to make the light and shade of the ink generated thereby uniform, so-called ink leveling is performed. In order to prevent the occurrence of bleeding at the time of printing due to the drop of ink adhering to the squeegee during the ink leveling work in the doctor in a screen printing machine that runs a doctor to perform It relates to a screen printing machine in which a scoop-shaped doctor receives the falling ink.

[0002]

[Prior art]

 2. Description of the Related Art Conventionally, various screen printing machines have been provided in which a squeegee and a doctor (scraper) that are reciprocally run print on a screen printing plate by a vertical reciprocal operation, and ink is leveled. That is, a squeegee and a doctor are arranged on the screen printing plate forward and backward with respect to the running direction, and when printing with a squeegee, the squeegee is lowered and the doctor located behind it is raised to run. In order to make the density of the ink generated during printing uniform, the so-called squeegee is raised during so-called ink leveling, and the doctor is lowered to make the ink uniform on the screen printing plate. is there. In addition, by tilting the rising squeegee toward the doctor at the time of ink leveling by lowering the doctor, it is possible to prevent ink from dripping from the squeegee during ink leveling and perform printing without smearing. There is also such a method (see Japanese Patent Publication No. 3-63952).

[0003]

[Problems to be solved by the device]

 However, at the time of leveling the ink, the squeegee is located in front of the doctor in the running direction, so if the viscosity of the ink is low, the ink attached to the squeegee will be in front of the doctor while running. As a result, the amount of ink is largely deviated at the dropped portion. That is, even if a doctor is used to average the entire ink surface, partial deviation on the screen printing plate surface, and further ink sneak on the printing surface side of the screen printing plate, resulting in printing Occasionally, bleeding occurs, resulting in an unclear printed surface. In addition, if the viscosity of the ink is high, even if the rising squeegee is tilted to the doctor side, it should be scraped by the doctor and dropped exactly into the ink reservoir formed to make it uniform. Is difficult. In any case, it is not possible to guarantee printing without bleeding, and if such bleeding occurs when printing the resist and circuit pattern on the printed circuit board, the printed circuit board itself becomes a defective product and the product yield deteriorates. It has certain drawbacks.

Therefore, the present invention has been devised in view of various existing circumstances as described above, and it is mainly a partial arrangement of a squeegee in a rising state during ink leveling to a screen printing plate surface. It is an object of the present invention to provide an improved screen printing machine that can prevent ink dripping, guarantee printing without blurring, and eventually improve product yield.

[0005]

[Means for Solving the Problems]

 In order to achieve the above-mentioned object, in the present invention, the squeegee 10 and the doctor 20 arranged in the front and rear in the running direction are turned upside down as they advance and retreat in the running direction, and are lowered by the squeegee vertical movement mechanism 12. The squeegee 10 is used to press the screen printing plate S coated with the ink K onto the surface of the material to be printed and rub it to perform printing, and the doctor 20 which is lowered by the doctor vertical movement mechanism 22 is used. In the case where the ink is leveled, the doctor 20 is made into a scoop shape, and when the doctor 20 is moved down by the doctor vertical movement mechanism 22, the doctor is moved up and down by the doctor forward / backward movement mechanism 29. The doctor 20 is arranged to move forward just below the existing squeegee 10, and the ink K from the squeegee 10 is dropped onto the doctor 20 during ink leveling. And it said that there was Unishi.

In addition, the doctor 20 has a horizontal fixed portion 20A, an inclined portion 20B inclined downward from the front end of the fixed portion 20A, and an ink receiving portion that is connected in a substantially horizontal manner via the inclined portion 20B. 20C.

Then, the doctor vertical movement mechanism 22 is guided by a slide guide 24 arranged along the upper and lower sides of the traveling base 1 by the operation of a slide cylinder 23 attached to the traveling base 1 for integrally traveling the squeegee 10 and the doctor 20. A slide block 25 that slides up and down is provided, and a doctor holder 21 that supports the doctor 20 is provided on the slide block 25. Further, the doctor forward / backward movement mechanism 29 is fixed to the lower surface of the doctor holder 21. A shaft base 31 is fixedly mounted on the base plate 30, and a front-rear movement cylinder 33 is fixed to one of a pair of shaft brackets 32 fixedly mounted on the front and rear sides of the shaft base 31, and a plunger of the front-rear movement cylinder 33 is fixed. Is installed between the shaft brackets 32. A guide block 35 slidably guided along the ride shaft 34 is fixed, and a floating stay 38 for supporting the doctor 20 can be connected.

[0008]

[Action]

 In the screen printing machine according to the present invention, the squeegee 10 that descends on the surface of the screen printing plate S at the time of printing presses the screen printing plate S against the surface of the printing material by its running to perform printing by rubbing. At the time of ink leveling, the traveling direction is reversed and the squeegee 10 rises, while the doctor 20 descends, and the scoop-shaped doctor 20 advances toward the squeegee 10 side by the operation of the doctor forward / backward movement mechanism 29 and its ink receiving portion. 20C is located directly below the squeegee 10.

When the doctor 20 located immediately below the squeegee 10 runs in this state, when the squeegee 10 running on the screen S of the screen performs ink leveling to make the ink K deviated during printing uniform. At the same time, the ink K dropped from the squeegee 10 is prevented from falling on the surface of the screen printing plate S. That is, during the ink leveling, the ink K dropped from the squeegee 10 is dropped and accumulated on the ink receiving portion 20C of the running doctor 20.

When the ink leveling is completed and printing is started again, the doctor 20 is retracted from the squeegee 10 side and raised, and at the same time, the doctor 20 is lowered in reverse interlocking with the squeegee 10. By running on the surface of the screen printing plate S in this state, the screen printing plate S is pressed and rubbed against the surface of the printing object to repeat printing.

[0011]

【Example】

 An embodiment of the present invention will be described below with reference to the drawings. In the drawings, reference numeral 1 indicates the left and right sides that can be moved by a drive mechanism on a printing table of a predetermined screen printing machine (not shown). It is a driving base that is arranged in. Between the traveling bases 1, a square pipe-shaped center pipe 2 that integrally travels the traveling bases 1 and a screen printing plate S on the printing table are pressed against the surface of the printing object and rubbed to perform printing. The squeegee holder 11 in the form of a square pipe that supports the squeegee 10 and the ink K that has accumulated in a state of being deviated due to printing are leveled while receiving the ink that is dripping from the squeegee 10, in synchronization with the return travel of the squeegee 10. A square pipe-shaped doctor holder 21 that supports a scoop-shaped doctor 20 that travels integrally is mounted.

Then, the squeegee 10 and the doctor 20 are in a state where the squeegee 10 is lowered and the doctor 20 is raised during printing in association with the traveling of the traveling base 1, and the traveling is reversed after the printing is finished during ink leveling. The doctor 20 descends at the same time as the squeegee 10 ascends before moving, moves forward to the side of the squeegee 10 and is located directly below it, and rubs the screen printing plate S while receiving ink K dripping from the squeegee 10. By doing so, the ink K is evened out. These operations control the squeegee vertical movement mechanism 12 attached to the traveling base 1 to move the squeegee 10 up and down, move the doctor 20 up and down, and move back and forth to move the doctor attached to the traveling base 1. This is performed by controlling the up / down moving mechanism 22 and the doctor forward / backward moving mechanism 29 associated with the doctor up / down moving mechanism 22.

As shown in FIG. 2, the doctor vertical movement mechanism 22 is vertically moved by being guided by a slide guide 24 arranged along the upper and lower sides of the traveling base 1 by the operation of a slide cylinder 23 attached to the traveling base 1. A slide block 25 that slides on the slide holder is provided, and the doctor holder 21 and the doctor 20 are moved up and down by the operation of the slide cylinder 23. This vertical movement lowers the doctor 20 until the lower end edge reaches the screen plate S surface after the printing of the traveling base 1 is completed, and the squeegee vertical movement mechanism 12 operates like the doctor vertical movement mechanism 22. The squeegee 10 is lifted by performing the reversal operation in timing, and the slide cylinder 23 is controlled so that the lower end edge of the doctor 20 is located immediately below the squeegee 10 when the doctor forward / backward moving mechanism 29 completes the forward movement toward the squeegee 10. (See FIG. 4).

The doctor back-and-forth moving mechanism 29 has a base plate 30 fixed to the lower surface of the doctor holder 21, and an angled shaft base 31 extending along the front and rear of the traveling base 1 in the traveling direction. The front-rear moving cylinder 33 is fixed to either one of the pair of shaft brackets 32 fixed in a front-to-rear manner, and the plunger of the front-rear moving cylinder 33 is fixed to the floating 37 which is screwed and fixed to the shaft. A guide block 35 slidably guided along a slide shaft 34 mounted between the brackets 32 is connected to a fixed floating stay 38, and the doctor 20 is supported on the lower surface of the floating stay 38. (See Figure 3).

As shown in FIG. 2, the doctor 20 itself has a horizontal fixing portion 20A for fixing to the floating stay 38 and an inclined portion 20B inclined downward from the front end of the fixing portion 20A. It is formed in a stepped shape in which the ink receiving portions 20C are continuously provided in a substantially horizontal shape. The entire doctor 20 has a width that is not smaller than the width of the squeegee 10 and is integrally bent with a plate material having an appropriate thickness, and the inclination angle of the inclined portion 20B is about 40 degrees. It has been done. Although not shown, the ink receiving portion 20C continuously provided through the inclined portion 20B may be provided with an inclination angle of about 20 degrees, and further, the horizontal ink receiving portion 20C front end or 2 may be provided. A vertical printing section may be provided at the tip of the ink receiving section 20C having an inclination angle of about 0 degree.

The doctor 20 is fixed to the floating stay 38 by fixing a band-shaped joint plate 40 along the width direction of the doctor 20 to the lower surface of the floating stay 38 and connecting a lock knob 41 arranged on the joint plate 40. It is designed to be inserted through the plate 40 and screwed to the lock plate 42 arranged on the lower surface of the fixed portion 20A of the doctor 20 (see FIG. 4). That is, the fixed portion 20A is sandwiched by the joint plate 40 and the lock plate 42 by the rotation operation of the lock knob 41, and the position of the fixed portion 20A with respect to the floating stay 38 can be changed by loosening and fastening the same. For example, it is possible to increase or decrease the ink receiving area of the ink receiving portion 20C located below the squeegee 10.

The base plate 30 has an engaging step that is engaged with the lower ends of both sides of a grip 43 that holds the doctor holder 21 from above and has a recess that fits into the lower surface of the doctor holder 21. Of the grip knob 44 screwed from the upper side of the grip 43, with the base plate 30 in contact with the lower surface of the doctor holder 21 and engaged with the grip 43. The entire doctor 20 including the doctor back-and-forth moving mechanism 29 is detachably fixed to the doctor holder 21 by being pulled toward the doctor holder 21 side. By doing this, the conventional doctor holder is formed as the doctor holder 21, and the doctor forward / backward movement mechanism 29 is set and fixed via the grip 43 and the grip knob 44, and the sequence control of hydraulic pressure, pneumatic pressure, and electric system is changed. By doing so, it can be easily incorporated into conventional machines.

Next, an example of the operation of the screen printing machine of the present invention will be described. At the time of printing, the squeegee 10 moves down to the screen printing plate S surface by the squeegee vertical movement mechanism 12, and in that state, the screen printing plate S surface By traveling above, the screen printing plate S is pressed against the surface of the printing object and rubbed against it to perform printing. Next, at the time of ink leveling, the traveling direction is reversed, the squeegee 10 is raised by the squeegee vertical movement mechanism 12, and in conjunction with this, the doctor 20 is lowered by the operation of the doctor vertical movement mechanism 22, and the doctor back and forth movement is also performed. By the operation of the mechanism 29, the scoop-shaped doctor 20 advances toward the squeegee 10 side, and the ink receiving portion 20C thereof is located immediately below the squeegee 10.

A doctor 20 located immediately below the squeegee 10 runs on the surface of the screen printing plate S to perform ink leveling on the surface of the screen printing plate S for uniformizing the ink K deviated during printing. The ink K dripping from the squeegee 10 is prevented from falling on the surface of the screen printing plate S.

When the ink leveling is finished and printing is started again, the doctor forward / backward moving mechanism 29 operates to retract the doctor 20 from the squeegee 10 side, and the doctor upper / lower moving mechanism 22 operates to cause the doctor 20 to move. When the squeegee 10 is lowered by the operation of the squeegee up-and-down moving mechanism 12 at the same time as the squeegee moves upside down, the squeegee 10 travels on the screen printing plate S surface in this state, and the screen printing plate S is pressure-bonded to the printing surface , Rub and repeat printing.

[0021]

[Effect of device]

 As described above, according to the present invention, when the scoop-shaped doctor 20 is lowered and the ink is leveled, the ink receiving portion 20C of the doctor 20 is disposed directly below the rising squeegee 10 to level the ink. Since the ink K dripping from the squeegee 10 is received on the ink receiving portion 20C, unnecessary dot-shaped ink K is dropped on the screen S of the screen as in the conventional case. It does not form the spots where fluttering occurs. Further, at the time of leveling the ink, when the doctor 20 rubs on the screen printing plate S so as to form the ink K in the form of a film, unnecessary dot-like ink K drops off the screen printing plate S. There is no concern that the ink K will go around to the printing surface side, which is the back side of the screen printing plate S, through the meshes of the screen. The resist and circuit pattern printing on the printed circuit board are very good, and the product yield can be greatly improved.

Further, the doctor 20 may be incorporated in place of the conventional control mechanism of the doctor (scrapper) for leveling the ink, which is incorporated in the conventional printing machine. Can be done without making a large change.

[Brief description of drawings]

FIG. 1 is a side view showing an outline of the present invention.

FIG. 2 is a side sectional view of a main part of the present invention.

FIG. 3 is a partially cutaway plan view of the present invention.

FIG. 4 is a partially cutaway front view of the present invention.

[Explanation of sign]

K ink S screen printing plate 1 traveling base 2 center pipe 10 squeegee 11 squeegee holder 12 squeegee vertical movement mechanism 20 doctor 20A fixed part 20B inclined part 20C ink receiving part 21 doctor holder 22 doctor vertical movement mechanism 23 slide cylinder 24 slide guide 25 slide block 29 Doctor longitudinal movement mechanism 30 Base plate 31 Shaft base 32 Shaft bracket 33 Longitudinal movement cylinder 34 Slide shaft 35 Guide block 37 Floating 38 Floating stay 40 Joint plate 41 Lock knob 42 Lock plate 43 Grip 44 Grip knob

Claims (3)

[Scope of utility model registration request] 1. A squeegee arranged in front and rear in the traveling direction, the doctor is turned upside down in the traveling direction, and the squeegee is lowered by a squeegee vertical movement mechanism. In a screen printing machine in which a plate is pressed against the surface of the printing material and rubbed to perform printing, and the ink is leveled by the doctor lowered by the doctor vertical movement mechanism, the doctor is formed into a scoop shape. Every time, when the ink is leveled by lowering the doctor by the doctor vertical movement mechanism, the doctor forward / backward mechanism is used to position the doctor forward just below the rising squeegee, and the ink from the squeegee is removed during the ink leveling. A screen printing machine characterized by being dropped onto a doctor. 2. The doctor comprises a horizontal fixing portion, an inclined portion inclined downward from a front end of the fixing portion, and an ink receiving portion connected in a substantially horizontal manner via the inclined portion. 1. The screen printing machine according to 1. 3. The doctor vertical movement mechanism slides up and down by being guided by a slide guide arranged along the top and bottom of the traveling base by the operation of a slide cylinder attached to the traveling base that integrally travels the squeegee and the doctor. A slide block to be installed is provided, and a doctor holder that supports the doctor is provided on this slide block.The doctor back-and-forth movement mechanism has a shaft base fixed to the base plate fixed to the lower surface of the doctor holder. The forward / backward moving cylinder is fixed to either one of a pair of fixedly mounted shaft brackets, and the guide of the forward / backward moving cylinder is slidably guided along the slide shaft mounted between the shaft brackets. The block is fixed and the doctor is supported. The screen printing machine according to claim 1, wherein the screen stays are connected to each other.