JPH0441653B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application: The present invention relates primarily to an improvement in a screen printing machine suitable for printing wiring boards.

Conventional technology: When printing using the conventional screen printing method,
The relationship between the printed object and the screen mold is such that after the printing operation, the screen mold is raised or the printed object is lowered to move the printed object from the bottom of the screen mold. Since the dimensions of the items handled by printing machines such as wiring boards are relatively small,
The operation of attaching and detaching the printed material is inconvenient, and automating this operation would complicate the equipment and make it expensive. Batch operation simplifies the mounting structure and reduces equipment costs, but it is difficult to handle. It is cumbersome to attach and detach the printing object onto the upper printing table, and the work efficiency is low because of the necessity of accurate positioning, and there is a desire to improve this efficiency.

Purpose of the Invention: The present invention has been made in view of the current situation, and it is possible to easily attach or remove a printing material at a fixed position on a support plate of a screen type that is fixedly supported in a fixed position. To provide a screen printing machine for small articles such as wiring boards, which can effectively utilize a narrow space and perform accurate printing operations.

Structure of the invention: In order to achieve such an object, the present invention has the following features:
The screen formwork is supported horizontally at the upper part between a pair of support frames and is kept in a fixed position, and the support surface plate that holds the printing material in a fixed position on the upper surface has its base end moved from the attached end of the screen formwork as appropriate. The free end side is pivotably supported on the support frame side at a remote position so as to be movable up and down, and the lower part of the free end side is connected with a pin to the rod end of a crank mechanism that moves intermittently, so that the crank mechanism and the above A squeegee device that is installed above the screen formwork and operates intermittently is such that both drive devices have a control mechanism so that the squeegee operates only when the supporting surface plate is horizontally supported below the screen form. The upper surface of the support surface plate has an adsorption means for temporarily holding the printing material in a fixed position and a contact plate made of a magnetic metal plate that is positioned by a magnet, and This screen printing machine is characterized by being equipped with a push-out pin for taking out the printing material and a fine adjustment mechanism for positioning the printing material on the front end side of the surface plate.

Embodiment: Hereinafter, one embodiment of the apparatus of the present invention will be described in detail with reference to the drawings.

Figures 1 to 4 show a screen printing machine for printed circuit boards used for electrical equipment, etc., in which a pair of box-shaped main frames 1, 1 are erected at appropriate intervals, and both main frames are Printing mechanism support frames 2, 2 are arranged symmetrically on the upper parts of 1, 1, and screen formwork support fittings 3 are attached symmetrically along the inner surfaces of these support frames 2, 2, respectively. Two (but not limited to) supporting metal fittings 3 are fixed to the frame in the longitudinal direction of the device at appropriate intervals within brackets 3'.
A support member 3b having a required length and a U-shaped cross section is attached to the lower side of the movable element 3'' which can be slid up and down by adjusting screws 3a. A plurality of formwork fixing push screws 3c with knobs are attached from the top surface and from the outside surface. By means of the left-right symmetrical formwork support fittings 3, 3, the screen formwork 4 of the required dimensions is supported and fixed on both sides by the support members 3b, 3b, and the screen surface is kept horizontal during installation. It will be done.

A squeegee 20 and its operating device 10 having the configuration disclosed in the prior invention (Japanese Unexamined Patent Publication No. 58-53442) are disposed at the upper part of the screen formwork 4, and this squeegee operating device 10 is , a squeegee operating device mounting frame 5, 5 provided along each inner surface of the printing mechanism support frames 2, 2 connects to the drive main shaft 2, which is installed between the support frames 2, 2.
The mounting frames 5, 5 are integrally connected at both front and rear ends by stays 6, 6' having a rectangular cross section.

The squeegee operating device 10 includes a pair of sliding support pieces 12 that are movable by being fitted onto two guide shafts 11 which are arranged parallel to each other at appropriate intervals between the stays 6 and 6'. A main connecting shaft 13 that is installed between 12 pairs of sliding support pieces and is rotatably supported, a sub connecting shaft 13' located below the main connecting shaft 13, and both connecting shafts 13,
A squeegee attachment piece 14 is positioned and supported at the center of the squeegee attachment piece 13', and a central part is attached to the connecting shafts 13, 13' so that the squeegee attachment piece 14 can slide vertically using grooves provided on both the front and rear sides of the squeegee attachment piece 14. Two sets of rocking pieces 15, 1 each supported and arranged in upper and lower stages
Slider 16, 1 connected with pins on both sides
6' and along each inner surface of the mounting frames 5, 5, the effective printing length of the screen is exactly equal to the chain wheel 1.
A pair of squeegee drive chains 17 are wound endlessly in a manner corresponding to the wheelbase between 7' and 17'' and the pitch circle diameter of both chain wheels, and one end is attached to each of the pair of chains 17 with a pin 18'. It consists of a pair of squeegee operating links 18 that are connected and whose other end is fixed to the end of the main connecting shaft 13.The drive mechanism of the chain 17 receives power from a motor M disposed within the box-shaped frame 1. The gears 27 fixed on the main drive shaft 25 and the gear 27' on the support shaft 26 of the chain wheel 17' on which the chain 17 is wound are meshed with each other. The chains 17 are designed to be driven in synchronization.The chains 17 are all kept in tension by a chain guide 19 installed along the inner surface of the mounting frame 5, and are moved. The side chain wheel 17'' is operated by the take-up to adjust the tension of the chain 17.

The squeegee 20 is attached to the squeegee mounting piece 14 described above.
A holder 22 is attached to a slider 16 attached to one surface of the slider 16 via an auxiliary piece 21, so that vertical and horizontal adjustment is possible. Further, at a position opposite to the squeegee 20, an ink scraping plate 23 is attached by a holder 23' and is adjustable via a slider 16' attached to the mounting piece 14.

The squeegee operating device mounting frames 5, 5 equipped with such a squeegee operating device 10 are integrally connected by the stays 6, 6' as described above.
The main drive shaft 25 can be rotated upward with reference to the bearing part, and locking shaft pins 7 are made to protrude sideways from the outside of the stay 6 mounting part at the front position, and the ends of the locking shaft pins 7 are A locking handle 7' is screwed together, and the shaft pin 7 is received in a notch 2' provided at the upper front end of the printing mechanism support frame 2, and is fixed by the locking handle 7' to keep it steady. When the lock handle 7' is operated to release the fixation, the main frame 1 side and the tension spring 8 are stretched at the rear end so that the mounting frame 5 and the squeegee operating device 10 can be lifted. It's summery.

In the supporting surface plate 30 for supporting the printing material for the printing mechanism 9 thus constructed, a bracket 31 bent backward from the lower surface of the base end in an inverted L shape is provided facing downward between the upper ends of the main frame 1. The tip of the projecting piece 32 is supported by a pin 33 so that it can be moved up and down between the lower surface of the screen 4' of the screen formwork 4 and its lower position. A hole 34 is bored, and a suction jacket 35 is attached to the lower surface, and one end of a hose 57 is attached to a connection port 35' provided at the end of this jacket 35 to connect it to a blower 56.
The printing material A is held by suction on the upper surface of the surface plate 30. Further, on the upper surface of the surface plate 30, a plurality of permanent magnet pieces 36 are embedded at required intervals around the printing material attachment part in which the small suction holes 34 are bored, and a fixing magnetic body ( A positioning piece 37 (mainly made of a steel plate) is attracted by a buried magnet piece 36 to hold the printing material in a fixed position, and the positioning piece 37' on the proximal side is attached to the lower end on the free end side of the surface plate 30. It is attached so that it can be finely adjusted via an adjusting screw 38 with a knob that is screwed into a protruding female adjusting piece 38'.

A length is provided between the tip of the inverted L-shaped bracket 39 attached to the lower surface of the free end side of the support surface plate 30 and an appropriate position on one side of the crank disk 41 disposed at the lower part between the main frames 1, 1. The pins 41' and 4 are connected to each other through a crank rod 42 which allows the height to be adjusted.
2' is connected to a timing pulley 44 fixed on a rotating shaft 43, the crank disk 41 is supported by a bearing, and a clutch brake 45 of a known structure is connected to a driving timing pulley 4 on an output shaft 45'.
A timing belt 46 is wound around the clutch brake 4', and power applied from the motor M to the input shaft side of the clutch brake 45 is transmitted. And the pulley 4 installed on the output shaft M' of the motor M
A clutch brake 49 separate from the clutch brake 45 is connected to a drive chain wheel 28 attached to the drive main shaft 25 of the squeegee operating device 10 and a chain wheel 51 attached to the intermediate shaft 50 by a belt 48 wrapped around the clutch brake 45 . Operation chain 17 of squeegee 20 via
The pulley 51' of the intermediate shaft 50 is used to drive the
A timing belt 52 is wound around the belt, and an electric control mechanism controls a clutch brake 49 for operating the squeegee and opening/closing operations of the substrate support surface plate 30. In order to operate the squeegee 20 only when the squeegee 20 is in the original position, the drive mechanism is operated so that the brake of the clutch brake 49 is released and the clutch is engaged, and the operation of the squeegee 20 is completed. The structure is such that the crank brakes 45 for crank operation are controlled in the order in which they are operated so that the support surface plate 30 is later moved away from the screen surface and tilted downward.

In addition, a push-out pin 55 for removing the printing material, which is operated by a solenoid, is provided at a position on the proximal side of the printing material mounting portion of the support surface plate 30.

Next, to explain the operation of the device of the present invention, first, in order to install the screen formwork 4 (screen type),
If the lock handle 7' is loosened and the locking shaft pin 7 fitted in the notch 2' of the printing mechanism support frame 2 is disengaged from the notch 2',
The front part of the squeegee operation device mounting frames 5, 5 is pulled upward based on the bearing part of the drive main shaft 25 by the force of the tension spring 8 attached to the rear end, and the screen formwork 4 is attached to the front part thereof. A space will be formed. Therefore, the support frame 2,
2. Insert the screen formwork 4 along each U-shaped support member 3b of the support fitting 3 provided on the inside, support it on both sides, and fix it with the fixing push screws 3c. 3a, operate the mover 3' so that the screen surface 4'' of the attached screen formwork 4 is level. (no adjustment required).
After the screen formwork 4 has been installed, the squeegee operating device installation frame 5 is lowered, the shaft pin 7 is fitted into the notch 2' of the support frame 2, and the lock handle 7' is tightened to secure it. ,
A squeegee 20 will be positioned on the screen formwork 4.

Next, in order to mount the substrate to be printed, for example, a board to be printed, on the support surface plate 30, the support surface plate 30 must be mounted on the bracket 31 attached to the base end in the state before starting work during operation of the apparatus. It is supported by a pin 33 and opened in a diagonally downwardly inclined state, and the inside of a jacket 35 attached to the lower surface of this surface plate 30 is connected to a blower 56 and is in a suction negative pressure state, and this jacket 35 and a large number of The target printing material A is placed on the suction surface formed through the small hole 34 and held there by suction (see FIG. 5). At this time, the printing material A is fixed on the surface plate 3 in order to fix it at the target position.
The magnet 36 embedded in the upper surface of the magnet 36 is fitted into the inner side surrounded by positioning pieces 37, 37' with a predetermined dimension.

When preparations are completed in this way, a control mechanism (not shown) gives an electric signal to start printing, and the clutch brake 45 on the supporting surface plate operating side of the drive device is activated, the brake is released, and the print starts instead. When the clutch is engaged, the crank disk 41 for operating the support surface plate rotates approximately 1/2 turn, and the support surface plate 30 is lifted up via the crank rod 42, so that the printing material is placed horizontally on the screen surface of the screen formwork 4. come into contact with Then, the clutch brakes 45 come to a halt in a preset order in the electric control device, and when the clutch brake 49 on the squeegee drive side operates instead, the power from the motor M is transferred from the chain wheel 51 on the intermediate shaft 50. It is transmitted to the drive main shaft 25 via the drive chain wheel 28, and the drive main shaft 25
With this rotation, the squeegee drive chain 17 is driven by the chain wheel 17' on the squeegee drive support shaft 26 via the gear 27 on the drive main shaft 25, the gear 27' that meshes with the gear 27, and the squeegee drive chain 17 is driven as shown in FIG. When starting to drive this chain 17, attach the end of the chain to the pin 18'.
The connected operation link 18 starts moving downward along the guide in the direction of arrow A (the starting position may be set in advance), and the squeegee 20 removes the ink placed on the top surface of the screen 4'. By scraping and moving to the reversal position along the chain wheel 17'' on the driven side, the desired screen printing is applied to the printing material A that is in contact with the lower surface of the screen 4'.Then, the operation link 18 is driven by the squeegee. When the chain 17 moves, it reverses along the driven side chain wheel 17'' and moves upward along the guide, the displacement of the operating link 18 causes the rotation of the main connecting shaft 13 to which the base end is attached. The rocking piece 15 fixed to the connecting shaft 13 is also inclined in the same way as the operation link 18, and the rockers 16, 16' connected to the rocking piece 15 are moved along the squeegee attachment piece 14 in opposite directions. After sliding displacement, the tip of the ink scraping plate 23 on the opposite side lightly contacts the screen instead of the squeegee 20 to scrape back the ink to the original position, and the drive of the chain 17 is stopped at the time of returning to the original position. During one reciprocating movement of the squeegee operating device 10, the pair of sliding support pieces 12 smoothly move along the guide shaft 11, allowing the printing operation to be performed without difficulty.

When the printing operation is completed in this manner, the operation of the clutch brake 49 on the squeegee drive side is stopped by the operation of the electric control mechanism, and instead the clutch brake 45 on the surface plate operation side is operated again. By rotating the crank disk 41 approximately 1/2 turn and stopping the crank rod 42 which is stopped in the pushed-up state, the support surface plate 30 is moved to the pivot pin 3.
Since the front part (free end) will descend diagonally downward from point 3, even when the printed material A separates from the screen surface 4'', it will gradually peel off from the front side, making it impossible to Can be released from the mold without any problems.

Until the above printing operation is completed, the printing material A is attracted to the support surface plate 30 on the attachment surface of the support surface plate 30 through the jacket 35 on the back side by suction negative pressure from the blower 56, and the positioning piece 37 , 37' prevents it from slipping from the surroundings, so that it continues to be fixed in place.
Therefore, after tilting the support surface plate 30 to the lowest position, the operator presses the operation button on the control panel to energize the solenoid to eject and operate the removal push-out pin 55, and removes the printed material A. Push up one side from the surface plate 30 to release the suction force and make it easy to pick up, the operator takes it out of the machine, attaches a new substrate to the surface plate 30 again in the same manner as described above, and starts printing. If so, the above operation will be performed. Note that the push-out pin 55 for taking out the printed material from the support surface plate 30 is designed to automatically return after being pushed out for a certain period of time, so that it will not interfere with the next mounting operation. There is no. In addition, when the dimensions of the printing substrate are changed, it is only necessary to use a positioning piece that matches the object to accurately measure the dimensions of the positioning piece, and the position can be adjusted as described above at the free end of the surface plate. The setting can be made by operating the adjustment screw 38 attached to the side.

Effects of the invention: As described above, according to the present invention, the screen mold is left stationary in a constant state, and the squeegee device is positioned so that the set scraping pressure acts on the spatula. With the relationship determined, the substrate to be printed is fixed on a surface plate that tilts up and down with respect to the screen surface, and during printing, it is brought into contact with the screen surface from below, and after printing, it is tilted to touch it from the edge. If the molds are released in sequence and the surface plate is tilted down to the lowest position, the printed material can be attached and removed manually, and the printed material can be fixed with suction force and handled easily, so that it can be easily handled by manual feeding. This made it possible to create a device that could easily perform screen printing.
Therefore, although it is a batch operation, all the operator has to do is attach and detach the substrate to the surface plate, and the rest is done automatically, allowing for efficient printing, and it is easy to handle even small-sized substrates. be.

Furthermore, since the printing mechanism is configured to operate by setting the printing mechanism under certain conditions and applying the printing material to the underside of the fixed screen, it also has the advantage of stably preventing the screen from elongating.

[Brief explanation of drawings]

The drawings show one embodiment of the invention,
Figure 1 is a general longitudinal sectional view, Figure 2 is an external sectional view,
FIG. 3 is a right side view of FIG. 1, FIG. 4 is a plan view, and FIG. 5 is a schematic diagram showing the printing mode. 1...Main frame, 2'...Notch, 2...
Printing mechanism support frame, 3... Screen formwork support fitting, 4... Screen formwork, 4'... Screen, 4''... Screen surface, 6, 6'... Stay, 5... Squeegee operating device mounting frame ,
7... Locking shaft pin, 7'... Lock handle, 8
... Tension spring, 9 ... Printing mechanism, 10 ... Squeegee operating device, 11 ... Guide shaft, 14 ... Squeegee mounting piece, 17 ... Squeegee drive chain, 1
8...Squeegee operation link, 20...Squeegee,
23... Ink scraping plate, 25... Drive main shaft,
30... Support surface plate, 31... Bracket, 32...
...Protruding piece on the main frame side, 33... Pin, 34...
Small hole for suction, 35... Jacket, 37, 37'
... Positioning piece, 38 ... Adjustment screw, 39 ... Bracket, 41 ... Crank disc, 42 ... Crank rod, 45, 49 ... Clutch brake,
55... Push-out pin for removing printed material, 56...
...Blower, 57...Hose, M...Motor, A
...Print material.

Claims (1)

[Claims] 1. With respect to the screen formwork, which is horizontally supported at the upper part between a pair of support frames and kept in a fixed position, the support surface plate that holds the printing material in a fixed position on the upper surface has its base end separated from the screen formwork attachment end. It is pivotably supported on the support frame side at an appropriately distant position and is provided so that the free end side can move up and down, and the lower part of the free end side is connected with a pin to the rod end of a crank mechanism that moves intermittently. The squeegee device that is installed above the screen mold and operates intermittently is such that both drive devices are controlled so that the squeegee operates only when the supporting surface plate is horizontally supported below the screen mold. The supporting surface plate has an adsorption means for temporarily holding the printing material in a fixed position and a contact plate made of a magnetic metal plate that is positioned by a magnet, on the upper surface of the supporting surface plate; A screen printing machine further comprising a push-out pin for taking out the printing material and a fine adjustment mechanism for positioning the printing material on the front end side of the support surface plate.