JPH069941U - Screen printing machine - Google Patents

Abstract

(57) [Abstract] [Purpose] The present invention detects the presence of foreign matter on the upper surface of a printed circuit board before screen printing,
An object of the present invention is to prevent printing failure and damage to the screen plate by not performing screen printing in a state where foreign matter is attached. [Structure] Printed circuit board (1
0) is sucked and placed on the XY-θ table (11), the substrate (10) is held from the upper surface so that the substrate (10) is not lifted by the pressing plate (24). Press 11). When the substrate (10) is pressed against the XY-θ table (11) by the pressing plate (24), it is determined whether or not the pressing plate (24) is at a predetermined position by the foreign matter detecting device (22). Detect with. Based on the detection result, it is detected that the foreign matter (23) is attached to the upper surface of the substrate (10).

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a screen printing machine for applying a coating material on a screen plate to a printed circuit board by a squeegee which is driven by a drive source to move through the screen plate.

[0002]

[Prior art]

 In this type of screen printing machine, if foreign matter such as chip parts adheres to the upper surface of the printed circuit board conveyed from the upstream side, if the printing operation is performed as it is, it may cause printing failure or the screen board Will be damaged.

[0003]

[Problems to be solved by the device]

 Therefore, before performing screen printing, it is detected whether or not foreign matter is attached to the upper surface of the printed circuit board, and screen printing is not performed when foreign matter is attached to prevent defective printing or damage to the screen plate. The purpose is to do.

[0004]

[Means for Solving the Problems]

 Therefore, the present invention is a screen printing machine that applies a coating material on a screen plate to a printed circuit board by a squeegee that is driven by a drive source through the screen plate and sucks the printed circuit board conveyed from the upstream side. A table to be placed, a pressing member that is lowered onto the upper surface of the substrate when the substrate is sucked and placed on the table to prevent the substrate from floating, and the pressing member pushes the substrate onto the table. It is provided with a detection device for detecting the presence of foreign matter on the upper surface of the substrate based on whether or not it is in a predetermined position when it is applied.

[0005]

[Action]

 With the above configuration, when the printed circuit board conveyed from the upstream side is suction-mounted on the table, the board is pressed against the table from above so that the board is not lifted by the pressing member. When the pressing member presses the substrate against the table, the detection device detects whether or not the pressing member is at a predetermined position. Based on this detection result, it is detected that foreign matter is attached to the upper surface of the substrate.

[0006]

【Example】

 An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 2, (1) is a screen printing machine, (2) is a supply conveyor section for supplying a print substrate (10) described later from an upstream device, and (3) is a board positioning section. is there.

(4) is a printing unit for printing paste solder, which will be described later, on the substrate (10), and (5) is a discharge conveyor unit for discharging the substrate (10) from the printing unit (4).

(7) is a recognition camera drive unit for driving the recognition camera (8).

Reference numeral (11) is an XY-θ table on which the printed circuit board (10) is mounted by suction. The X motor (12), the Y motor (13) and the θ motor (14) are used for X, Y and θ tables. It can be moved in any direction.

The table (11) is driven by the X motor (12) along a pair of X guide rails (16) provided on the base (15) to rotate the X screw shaft (17) to move the X nut. Move in the X direction through the body (18). Therefore, the X guide rail (16) is provided so that the table (11) can move within the range from the base plate positioning section (3) to the printing section (4).

In addition, as shown in FIG. 1 and the like, a concave portion (21) is provided on the upper surface of the table (11) for the pre-installed component (20) to enter when the pre-assembled component (20) is present on the lower surface of the substrate (10). ) Is provided.

Reference numeral (22) is a foreign matter detection device for detecting a foreign matter (23) attached to the substrate (10), which will be described below.

Reference numeral (24) is a cylinder mounting plate (25) fixed to the base (15) side in order to prevent the substrate (10) from floating when the substrate (10) is mounted on the table (11) by suction. ) Is a pressing plate that is lowered by a drive of a cylinder (26) attached to the upper surface of the substrate (10) through a guide (27), and the pressing plate (24) is a rod (28) of a cylinder (26). The metal fitting (30) provided on the pressing plate (24) is abutted on the pressing plate (24) by the urging force of the spring (29) located around the guide (27). The upper end of the guide (27), the lower end of which is fixed to the pressing plate (24), is loosely inserted into the insertion hole (31) formed in the cylinder mounting plate (25).

Reference numeral (32) is a detection sensor for detecting the lift of the pressing plate (24) due to the foreign matter (23) based on the lift of the guide (27). For example, the light irradiated on the upper surface of the guide (27) is reflected. If the foreign matter (23) is present on the substrate (10) when it is not returned, it is detected.

Next, the recognition camera drive unit (7) will be described.

Reference numeral (34) is an X moving body, which is rotated along the X camera guide (38) via the nut (37) by the rotation of the X camera screw shaft (36) driven by the X camera drive motor (35). Move in the X direction. Although not shown, there is also a mechanism for moving in the Y direction similarly. Thereby, the position of the substrate (10) and the position of the screen plate (40) described later are recognized.

Next, the printing unit (4) will be described.

(41) is a screen mount to which the screen plate (40) is mounted.

Reference numeral (42) denotes two opposed squeegees provided on a squeegee base (not shown), which is guided by a squeegee vertical guide (43) and is vertically movable by the operation of the squeegee vertical cylinder (44). ing. The squeegee (42) descends and is horizontally moved on the screen plate (40) by driving a printing motor (not shown) so that the paste solder passes through a pattern hole formed in the center of the screen plate (40). And printed on the printed circuit board (10) on the XY-θ table (11). The angle of the squeegee (42) can be variously changed according to the viscosity of the paste solder, the pattern hole diameter, and the like.

Next, the control system will be described.

In FIG. 4, reference numeral (47) denotes a CPU, which performs various operations related to the printing operation of the printed circuit board (10) of the screen printing machine (1) based on the information stored in the RAM (48) in the ROM (49). ) According to the program stored in.

Reference numeral (50) is an interface for connecting an operation unit (53), a CRT (51), a detection sensor (32), etc., which will be described later. (52) is a drive circuit for driving each motor and each cylinder.

Reference numeral (53) is an operation unit, such as a numeric keypad (54) for inputting data, a cursor key (55), a teaching key (56) for setting an NC data setting mode, and a start key for starting operation. (57), a stop key (58) and a SET key (59) for stopping the operation are provided.

The operation will be described below.

First, when the operator presses the start key (57), the X motor (12) rotates, the XY-θ table (11) approaches the supply conveyor section (2), and the printed circuit board (10). ) Stop at a position where you can inherit. Then, the conveyance of the print substrate (10) is started by the supply conveyor section (2), the substrate (10) is placed on the table (11), and the table (11) is rotated by rotating the X motor (12). ) Moves away from the supply conveyor section (2).

Next, as the cylinder (26) is driven, the pressing plate (24) is lowered onto the base plate (10) as shown in FIG. 6, and the substrate (10) is urged by a spring (29). Press on the table (11) via. Then, the substrate (10) is placed on the table (11) by suction. When there is a preliminarily attached component (20) on the back surface of the substrate (10), the component (20) enters the recess (21) formed in the table (11). At this time, the light emitted from the detection sensor (32) of the foreign matter detection device (22) to the guide (27) is reflected and received by the detection sensor (32) again. It can be detected that 23) is not attached.

A case where the foreign matter (23) is attached will be described with reference to FIG.

As shown in FIG. 1, the pressing plate (24) is tilted by the foreign matter (23) attached to the substrate (10) and lifted against the urging force of the spring (29) at four positions. If any one of the detection sensors (32) provided in the above can not receive light, it can be detected that there is a foreign matter (23). That is, the presence of the foreign matter (23) causes the pressing plate (24) to tilt due to the presence of the foreign matter (23), and the light emitted from the guide (27) to the tilt detection sensor (27) is not correctly reflected and cannot be received. Will be detected.

Further, as shown in FIG. 7, even when the pre-attached component (20) does not enter the recess (21), the pressing plate (24) is tilted and light is received similarly to the above-mentioned foreign matter detection. It is detected that an abnormality has occurred due to the occurrence of the non-existent detection sensor (32). Then, based on the detection result of the detection sensor (32), the CPU (47) notifies the operator of the abnormality through a notifying device (not shown) and stops the screen printing machine (1).

Next, the position of the substrate (10) is recognized by the recognition camera (8).

That is, the recognition camera (8) moves X and Y on a positioning mark (not shown) of the substrate (10) to recognize the position of the substrate (10). Based on this recognition result and the recognition result of the already recognized position of the screen plate (40), the base plate (10) becomes the position to be positioned at the center of the screen plate (40) with respect to the screen plate (40). Thus, the XY-θ table (11) moves XY by the rotation of the X motor (12) and the Y motor (13) and stops below the screen plate (40). After that, the table (11) is rotated in the θ direction by the rotation of the θ motor (14), and the substrate (10) is positioned at a position to be positioned with respect to the screen plate (40).

Next, the screen plate (40) is lowered to a position where paste solder can be applied to the substrate (10) by an elevating means (not shown).

After that, the printing operation of the paste solder on the substrate (10) by the movement of the squeegee (42) is performed. This printing operation will be described.

For example, when the squeegee (42) on the right side is lowered by the operation of the syringe up-and-down cylinder (44), the printing motor rotates and the squeegee (40) moves horizontally while imprinting the paste solder on the substrate (10).

Next, the XY-θ table (11) on which the substrate (10) is placed is set to a position where the substrate (10) can be discharged by moving in the Y direction and rotating in the θ direction, and the X motor ( The rotation of (12) moves to the discharge conveyor section (5) side, and stops at a position where the substrate (10) can be discharged to the discharge conveyor section (5).

Next, the rotation of the X motor (12) moves the XY-θ table (11) to the supply conveyor section (2) side. Then, the next substrate (10) is received from the supply conveyor section (2), and the fixing operation of the substrate (10) and the foreign matter detecting operation are performed in the same manner as described above, and the substrate (10) is positioned below the screen plate (40). Then, the screen plate (40) descends to print the paste solder by the squeegee (42).

The recognition camera (8) may detect the foreign matter (23) on the printed circuit board (10).

[0039]

[Effect of device]

 As described above, according to the present invention, the presence of foreign matter on the upper surface of the printed circuit board is detected before the screen printing, so that the screen plate may be damaged or the screen printing cannot be performed accurately. It can be prevented.

[Brief description of drawings]

FIG. 1 is a diagram showing a foreign matter detection device.

FIG. 2 is a front view of a screen printing machine.

FIG. 3 is a plan view showing a foreign matter detection device.

FIG. 4 is a control block diagram.

FIG. 5 is a side view showing a foreign matter detection device.

FIG. 6 is a side view showing a foreign matter detection device.

FIG. 7 is a side view showing another embodiment of the foreign matter detecting device.

[Explanation of symbols]

 (10) Printed circuit board (23) Foreign matter (24) Holding plate (32) Detection sensor

Claims (1)

[Scope of utility model registration request] 1. In a screen printing machine for applying a coating material on a screen plate to a printed circuit board by a squeegee which is driven by a drive source through the screen plate, a printed circuit board conveyed from the upstream side is adsorbed. A table to be placed, a pressing member that is lowered onto the upper surface of the substrate when the substrate is sucked and placed on the table to prevent the substrate from floating, and a state in which the pressing member presses the substrate against the table. A screen printing machine, characterized by further comprising: a detection device for detecting foreign matter adhering to the upper surface of the substrate based on whether or not it is at a predetermined position.