JP3064629B2 - Screen printing machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a screen printing machine, and more particularly, to the recovery of a printing agent placed on a screen.

[0002]

2. Description of the Related Art A screen printing machine is an apparatus for printing a printing agent at a predetermined position on a plate to be printed, such as a case where an adhesive or cream solder is applied to an electronic component bonding position or a lead connection position on a printed circuit board. Which is known from Japanese Utility Model Laid-Open No. 1-63169. This screen printing machine
And the printing plate support, and the screen support table, and a squeegee device, skiing squeegee longitudinally extending squeegee device
Moving in the direction perpendicular to the longitudinal direction
As a result, the printing agent is printed on the printing plate supported by the printing plate support base.

[0003]

In such a screen printing machine, the printing agent supplied on the screen may remain after printing, which may cause inconvenience. For example, when printing cream-like solder on a printed circuit board, the screen is replaced when necessary, such as when the type of printed circuit board changes, but the creamy solder solidifies when left in the air Therefore, if the screen is replaced while the cream-like solder remains, the cream-like solder solidifies on the screen, requiring much time for cleaning, and the remaining cream-like solder cannot be reused, resulting in waste. Other than when replacing the screen, the same problem occurs if the creamy solder is left on the screen due to interruption of printing, etc.In addition to printing creamy solder on the printed circuit board, If the printing agent remains, various problems occur, such as a possibility that the printing agent may adhere to the conveying member during the conveyance of the screen and become dirty. Therefore, it is necessary to manually remove the printing agent remaining on the screen, which is troublesome.
Each respective inventions of claims 1 to 3, which was made as object to provide a screen printing machine which can automatically recover the remaining printing agent on the screen.

[0004]

Means for Solving the Problems of claims 1 invention, in order to solve the above problems, the object to be printed plate support, the screen support table, in a screen printing machine having a scan Chigi apparatus and the squeegee moving device , The squeegee device,
Two squeegees facing each other in the moving direction;
Each of these two squeegees touches the screen
The screen to a position that is separated from the screen
Includes a squeegee lifting device and can print in both directions
And before being placed on the screen
A printing agent collecting device for collecting the printing agent is provided, and the printing agent is collected.
The collection device consists of (1) the collection device body and (2) the collection device
The body has a rotation axis parallel to the longitudinal direction of the squeegee.
(3) a scooping member rotatably mounted on the
Rotate the scooping member in the forward and reverse directions.
Including a scraping member rotating device and (4) a control device
And the control device is provided with (4) -1 the scooping member rotating device.
By controlling the position and the squeegee elevating device,
Touch one of the two squeegees to the screen
And one of the squeegees faces the other squeegee
On the side surface to prevent the movement of the printing agent on the screen.
In the state, the scooping member is moved to the tip of the scooping member.
While contacting the edge to the screen,
Is rotated in the forward direction, which is the heading direction, to prevent the movement.
A scooping control unit that scoops the stopped printing agent
And (4) -2 connecting the other squeegee to the scooping member.
Touch the scooping surface, and
Printing agent on the scoop surface on the side facing the other squeegee
With the rake member in the reverse direction
To remove the printing agent from the scooping member.
And a return control unit for returning to the clean top.
It is characterized by the following. The invention of claim 2 is a claim
Item 1. The screen printer according to Item 1, wherein the two
Squeegee, the squeegee lifting device, the scooping section
Material and the scooping member rotating device, the collecting device
The collection device main body is supported by the main body, and the collection device main body is
It can be moved by a moving device
It is assumed that. The invention of claim 3 is claim 1 or
In the screen printing machine according to the second aspect, the rake
The take-up member is raised and lowered with respect to the main body of the collecting device, and the
Equipped with a scooping member lifting device
It is characterized in that

[0005]

[Action] Printing agent on the screen in a screen printing machine according to a first aspect of the invention, when a screen replacement, the automatically recovered by the printing agent recovery device optionally
In both cases, the recovered printing agent is automatically displayed on the screen.
Is returned to. When collecting printing agent on the screen
Is controlled by the scooping member rotating device and the squeegee elevating device.
Control by the scooping control unit of the
And take a scoop with one of the two squeegees.
Cooperates with the cutting member to remove the printing agent
It is taken and collected. One squeegee to screen
With the transfer of the printing agent on the
The squeegee on one side while the material is in contact with the screen
Is swung in the positive direction toward
It is. Also, place the collected printing agent back on the screen.
In this case, the rotation of the
The two squeegees are controlled by the
Cooperation between the other squeegee and the scooping member
Print agent from the scooping member onto the screen
Will be returned. The squeegee that has been brought into contact with the
The printing agent on the rake face is standing on the rake face
In order to prevent movement,
The printing agent on the rake face
It's squeezed by the key and put it on the screen
It is. In the screen printing machine according to the second aspect of the present invention, the main body of the collecting device is moved by the squeegee moving device.
Squeegee, squeegee lift
The scooping member and the scooping member rotating device
They are simultaneously moved in a direction parallel to the screen. In the screen printing machine according to the invention of claim 3, preparative salvation
Rake member is rotated by the rake member rotation device
At the same time, the scooping member elevating device
It is raised and lowered.

[0006]

According EFFECTS OF THE INVENTION Thus the invention of claim 1, automatically collected the printed material on the screen The screen
Can be returned to the top , and can be recovered easily and quickly compared to when the operator recovers or returns , and
Requires no human intervention. Also, the printing agent is a scooping member and two
Collected in cooperation with a squeegee and returned to the screen
Therefore , the printing agent can be reliably collected and returned . In addition, since collection and return are performed using a squeegee, the number of parts of the printing agent collection device can be reduced,
A simple and inexpensive printing agent collecting device can be obtained. Further, a screen printing machine equipped with two squeegees has the advantage of being able to perform reciprocating printing, but the printing agent can be collected and returned using each of the two squeegees, and Since the collection and return of the printing agent are performed by the surfaces (front surfaces) of the two squeegees facing each other, the printing agent does not adhere to the back surface of the squeegee. Since the surface of the squeegee always comes into contact with the printing agent during printing, it is inevitable that the printing agent adheres, and the squeegee may adhere. On the other hand, if the printing agent adheres to the back surface, the printing agent is not used for printing and is wasted, and the squeegee is contaminated by alteration and solidification, but this can be avoided. Besides, scoop
The take-off member is moved from the screen of the printing agent by a rotational movement.
To scoop and return to the screen,
Move the chamfer linearly in a direction parallel to the screen.
Printing agent recovery compared to when collecting and returning
The configuration of the collecting device can be simplified.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a printed circuit board screen printer will be described in detail with reference to the drawings. The screen printing machine shown in FIGS. 6, 7 and 8 includes a substrate conveyor 12, a substrate positioning and supporting device 14, a screen positioning and supporting device 16, a squeegee device 18, and a solder collecting device 20 for transporting a printed circuit board 10 as a plate to be printed. (See FIG. 6), the screen transport device 2 shown in FIG.
2, screen storage device 24, screen cleaning device 26
It has.

[0008] As shown in FIG.
A pair of rails 32 and 34 provided on the base 30 are provided. A rope (not shown) is annularly disposed on each of the rails 32 and 34, and the printed circuit board 10 is transported by circulating the rope. The distance between these rails 32 and 34 is
It can be adjusted according to the size of 0. Further, the substrate positioning and supporting device 14 includes a substrate supporting table 38 as a substrate to be printed. The substrate supporting table 38 is moved up and down by an elevating device (not shown). The printed board 10 transported by the substrate conveyer 12 and stopped by a stopper (not shown) and positioned by a positioning pin (not shown) is vacuumed. At the same time, it is lifted from the substrate conveyor 12 and brought into contact with the screen.

The screen positioning support device 16, squeegee device 18, and solder recovery device 20 are supported by a pair of frames 40 and 42 which are mounted on the base 30 so as to be able to move up and down. As shown in FIGS. 6 and 8, four columns 44 are erected on the base 30, and levers 46 and 47 are respectively mounted on the columns 44 so as to be rotatable around a horizontal axis by a shaft 48. As shown in FIG. 8, one frame 40 is attached to a pair of levers 46 which are separated from each other in a printed board conveying direction (left and right directions in the figure) so as to be rotatable around a horizontal axis, and The frame 42 is attached to the remaining pair of levers 47 so as to be rotatable around a horizontal axis.

A pair of levers 46 for supporting the frame 40
As shown in FIGS. 6 and 8, an arm 54 extends at a right angle from a portion where the frame 40 is connected to the shaft 48, and each end of the arm 54 is Are linked. The other end of one lever 46 of the pair of levers 46 is connected to a rotating plate 6 by a rod 58 disposed in a vertical direction.
0 so as to be rotatable. The rotating plate 60 is provided with a gear 6 rotated by a lifting motor 62 (see FIG. 8).
4 is fixed to the shaft 68 of the gear 66 meshed with the gear 4. Similarly, as shown in FIG. 8, arms 70 are fixed to the other pair of levers 47 supporting the frame 42, and are connected by rods 72. One lever 47 has a rod 74 extending vertically. And a rotating plate 75 rotatably connected to the lower end of the rod is fixed to a shaft 68. Therefore, if the shaft 68 is rotated by the lifting motor 62, the rotating plates 60 and 75 are rotated, and the four levers 46 and 47 are simultaneously rotated by 90 degrees as shown by a two-dot chain line in FIG. Rotated, the screen positioning support device 1
6, the squeegee device 18 and the solder recovery device 20 are located directly above the substrate support base 38 as shown by solid lines in FIGS. 6 and 7, and the lower end position where screen printing is performed; Is moved higher than the lower end position and to the upper end position that has moved downstream in the printed board transport direction. The above-mentioned devices 16, 18, 20 are two sets of parallelogram link devices constituted by a base 30, on which four columns 44 are erected, levers 46, 47 and frames 40, 42, and one lever 46, 47. 54, 70, rods 56, 72, and motor 62, gears 64, 6
It is moved up and down by an elevating device consisting of a drive device constituted by the rod 6 and the rods 58, 74 and the like.

The screen positioning support device 16 is provided below the frames 40, 42. As shown in FIGS. 6 and 7, a total of four brackets 76 are fixed to the lower surfaces of the frames 40 and 42, and a screen support 78 is attached to the brackets 76, and is fixed to the screen 80 and its periphery. The screen frame 82 is supported. Screen 80
As shown in FIG. 5, through-holes 83 are formed on the front and back surfaces of the printed circuit board 10 at positions corresponding to the printing positions.
And printed on the printed circuit board 10. The screen support 78 is a rectangular frame, on which the screen frame 8 is mounted.
2 is placed, and the position in the X-axis direction parallel to the printed board transport direction and the position in the Y-axis direction orthogonal to the X-axis direction in the horizontal plane are respectively positioned by the X-axis direction positioning device and the Y-axis direction positioning device. The screen is fixed to the screen support base 78 by a fixing device.

Next, the squeegee device 18 will be described with reference to FIGS. The squeegee device 18 has a slide 84 as shown in FIG. Guide blocks 86 and 87 are fixed to both sides of the slide 84, respectively.
Guide rails 88 and 90 fixed to the frames 40 and 42, respectively, are movably fitted. Slide 84
, A nut 92 is fixed, and both ends are screwed to a screw shaft 94 supported by one frame 42, and the screw shaft 94 is connected to a squeegee moving servomotor 96.
(See FIG. 11), the slide 84 is moved in the X-axis direction.

A frame 100 is fixed on the slide 84. The frame 100 includes a pair of side walls 102, a top wall 104, and a back wall 106, as shown in FIGS.
The slide 84 and the frame 100
Are provided with a first squeegee unit 108 and a second squeegee unit 110. These units 108,
The configuration of the first squeegee unit 10 is the same.
8 will be described in detail.

The first squeegee unit 108 has a first squeegee 112 and is provided with a first squeegee elevating portion 117 which is raised and lowered by a pair of first squeegee elevating air cylinders 114 and 116 (see FIG. 2). These air cylinders 114 and 116 are fixed downward on the top wall 104 and spaced apart in the Y-axis direction, and their piston rods 118 and 120 (see FIG. 2) are inserted through the top wall 104 and the lower ends thereof. Rods 12 respectively fixed to the parts
2 and 124 (see FIG. 3) are slidably fitted in a pair of guide cylinders 126 and 128 erected on a slide 84, and a squeegee holder 130 is rotatable at the lower end thereof. Are linked.

As shown in FIG. 3, the squeegee holder 130 has a square member 132, brackets 134 and 136 fixed to both ends of the square member 132 in the longitudinal direction, and a support member having both ends fixed to the brackets 134 and 136. Member 1
38 has a fixed mounting plate 140. As shown in FIG. 3, elongated holes 142 and 144 are respectively formed at two places in the longitudinal direction of the square member 132 which are separated from each other by a distance.
The lower ends of 22, 22 are fitted respectively,
It is rotatably connected to the square member 132 by pins 146 and 148 parallel to the moving direction of the slide 84. Rod 1
The inner diameters of the pin holes 150 and 152 in which the pins 146 and 148 of the pins 22 and 124 are fitted are slightly larger, and the squeegee holder 130 can rotate a small angle in a vertical plane including the rods 122 and 124. .

The first squeegee 112 is mounted on the mounting plate 140 as shown in FIG. The first squeegee 112 has a long plate shape, and includes a first squeegee member 154 made of rubber and held by a squeegee holder 156. The lower end of the first squeegee member 154 is inclined and held in a direction away from the second squeegee unit 110. The first squeegee 112 includes the squeegee holder 15.
At 6, it is fixed to the mounting plate 140 and rotates together with the squeegee holder 130 in a vertical plane. In FIG.
Numerals 58 are shielding plates attached to both ends in the longitudinal direction of the squeegee holder 156 to prevent the creamy solder from protruding during printing. When the size of the printed circuit board 10 changes, the first squeegee 112 is attached to and detached from the squeegee holder 130, and the first squeegee member 154 is formed.
Is exchanged for one having a length corresponding to the dimensions of the printed circuit board 10.

As shown in FIG. 3, an elongated hole 160 is formed in the center of the square member 132 in the longitudinal direction, and a lower end of a lifting rod 162 is fitted thereinto.
Is rotatably connected to the square member 132. The lifting rod 162 has a through hole 165 formed in the slide 84.
, And is urged upward by a spring 170 disposed between a spring receiver 166 attached to the projecting end and a spring receiver 168 fixed to the lower surface of the slide 84. Accordingly, the first squeegee 112, the squeegee holder 130, the piston rods 118 and 120, the rod 1
22, 124, lifting rod 162 and spring receiver 166
And the like, and lift air cylinders 114, 116.
Therefore, the weight of the first squeegee elevating unit 117 which is raised and lowered by the above is reduced. In this embodiment, the spring 17
When the first squeegee 112 is lowered until the first squeegee 112 comes into contact with the screen 80, the weight of the spring load is reduced to zero, and the spring load is set so that no weight is applied to the screen 80. Therefore, the first squeegee member 154
When the pressure of the air supplied to the upper air chambers of the air cylinders 114 and 116 is zero, the screen 80 contacts the screen 80 with zero force, and the contact force increases as the air pressure increases.
During non-printing, the upper chambers of the air cylinders 114 and 116 are released to the atmosphere, while air is supplied to the lower chamber, and the first squeegee 112 is raised to the raised end position and separated from the screen 80. . A dog 172 is mounted on the spring receiver 166, and the lower end of the first squeegee member 112 is detected by a squeegee lower end sensor 174.

The second squeegee unit 110 has the same configuration, and the second squeegee elevating unit 178 is moved up and down by a pair of second squeegee elevating air cylinders 180 (only one is shown in FIG. 1). A rod 184 is connected to the lower end of the piston rod 182 of the second squeegee elevating and lowering air cylinder 180.
Squeegee holder 1 rotatably attached to the lower end of the squeegee
A second squeegee 188 is attached to 86. The second squeegee 188 is formed by holding a long plate-shaped rubber second squeegee member 190 by a squeegee holder 192, and the lower end of the second squeegee member 190 is inclined in a direction away from the first squeegee member 154. And are held. Further, the lifting rod connected to the square member of the squeegee holder 186 is urged upward by a spring, and the second squeegee 188 and the squeegee holder 18 are urged upward.
6, the piston rod 182, the rod 184, and an elevating rod (not shown) constitute a second squeegee elevating unit 178, and the weight of the second squeegee elevating unit 178 is reduced by a spring. The spring load of the spring is sized so that the weight applied to the screen 80 when the second squeegee 188 just contacts the screen 80 becomes zero. The contact pressure of the squeegee member 190 to the screen 80 can be adjusted. Further, the falling end of the second squeegee member 188 is detected by the dog 194 and the second squeegee falling end sensor 196.

The first squeegee 112 and the second squeegee 188 are used alternatively. Screen printing is performed by moving the squeegee from one side of the printed circuit board 10 to the other side, and the squeegee located upstream in the moving direction is used for printing. When two sets of squeegees are provided as described above, reciprocal printing can be performed by selectively using them according to the printing direction.

Next, the solder collecting device 20 will be described. As shown in FIG. 1, a pair of guide rails 200 (only one is shown in the figure) extending vertically are provided on the back wall 106 of the frame 100 at a distance in the Y-axis direction. 202 is a guide block 204, 20
At 6, it is fitted so as to be able to move up and down. This lifting plate 20
2, a plate 207 is fixed in a direction in which the plate 207 extends upward, and a piston rod 210 of a scooping member elevating / lowering air cylinder 208 provided on the top wall 104 is connected by a bracket 211. The elevating plate 202 is moved up and down by the expansion and contraction of.

The lower end of the lift plate 202 is defined by a bolt 212 screwed to the lower surface thereof abutting a stopper bolt 214 fixed to the slide 84. A mechanical valve 216 is attached to the side wall 102 of the frame 100 as shown in FIG.
02 can be switched between high and low speeds. As shown in FIG. 4, a switching plate 218 is fixed to the elevating plate 202. At the time of elevating and lowering, the first switching surface 220 protruding toward the mechanical valve 216 and the second switching surface 222 retracted therefrom are sequentially provided with the mechanical valve. 216, the switching lever 224 is brought into contact with the switching lever 224.
24, the switching lever 224 is moved to the first
20, the amount of air supplied to the air cylinder 208 is reduced and the vertical speed is reduced. On the other hand, in the state of contact with the second switching surface 222, the amount of air supplied is increased and the vertical speed is increased.

As shown in FIGS. 1 and 3, a support plate 232 is provided at each of the lower ends of the lifting plate 202 from both ends in the width direction.
Are extended forward. Each of these support plates 232 has a substantially L-shape, and is inserted into a notch 236 formed in the slide 84, and an arm 234 extending in the vertical direction faces a side surface of the squeegee holder 130 of the first squeegee unit 108. Have been allowed. A scooping device 237 is rotatably attached to these support plates 232. The scooping device 237 includes a pair of L-shaped brackets 238, a mounting plate 242 attached to each of the L-shaped arm portions 240 of the brackets 238, and a scooping device fixed to the tips of the mounting plates 242. The other arm 246 of the bracket 238 is fitted in a long hole 248 (see FIG. 3) formed in the support plate 232 and is rotatably attached by a pin 250.

A notch 252 is formed in the lower surface and the distal end surface of the arm portion 240. The mounting plate 242 is fitted into the notch 252 at one end thereof.
It is supported by a pin 253 so as to be rotatable around an axis parallel to the Y-axis direction. This mounting plate 242 is used for the arm 2
The other end is urged toward the screen 80 by a spring 256 disposed between the lower surface of the plate 40 and a fixed plate 254. Reference numeral 258 denotes a bolt that regulates the urging force of the spring 256. The scooping member 244 is longer than the first squeegee member 154 and
The pair of side walls 262 at both ends are respectively located on both sides in the longitudinal direction of the first squeegee member 154 as shown by a two-dot chain line in FIG. Rake member 244
Are exchanged according to the size of the first squeegee member 154, and have a length such that the side wall 262 can always sandwich the first squeegee member 154 from both sides in the longitudinal direction. The bottom wall of the scooping member 244 is curved along an arc centered on the axis of the pin 250, and the upper surface thereof is a partially cylindrical scooping surface 266. A knife edge 268 is formed at the tip of the scooping member 244.

The pair of brackets 238 are connected by a horizontally disposed rod 270, and a piston rod 274 of a scooping member rotating air cylinder 272 is connected to a joint member 276 at the longitudinal center of the rod 270. Are connected so as to be rotatable. The air cylinder 272 is rotatably connected to a plate 207 attached to the elevating plate 202 by a pin 280.
38 is rotated, scooping member 244 supported on the lifting plate 202 is moved along the screen 80, creamed solder collection, intends row back.

As shown in FIG. 3, a pin 284 is fitted to the lower end of the arm portion 234 of the support plate 232 so as to be movable in the Y-axis direction, and can be moved by a pin driving cylinder 286. ing. In the upper ends of the brackets 134 and 136 of the squeegee holder 130, fitting holes which are almost concentric with the pins 284 when the first squeegee 112 is lowered to the lower end and the lifting plate 202 is lowered to the lower end. The elevating plate 202 and the first squeegee 112 are connected by fitting the pin 284 into the fitting hole 288.

Screen 8 used for screen printing
A value of 0 is replaced with another screen 80 when necessary, such as when printing is performed for a predetermined number of times or when the type of the printed circuit board 10 is changed. The screen transport device 22 includes:
The screen 80 is conveyed between the screen positioning support device 16 and the screen accommodating device 24, and the screen is automatically exchanged.
This is the same as the device described in JP-A-317768, and will be briefly described.

As shown in FIGS. 6 and 7, the screen transport device 22 includes an X-axis slide 29 which moves in the X-axis direction.
0, and a Y-axis slide 292 provided on the X-axis slide 290 and moving in the Y-axis direction. Each of the X-axis slide 290 and the Y-axis slide 292 is provided with an engagement member that engages with the screen frame 82, and pulls out the screen frame 82 from the screen support base 78 and conveys the screen frame to the screen storage device 24. The screen accommodating device 24 has upper and lower two-stage screen accommodating portions which are moved up and down by the elevating device. The screen accommodating portions are selectively positioned at the screen transfer position, and are removed from the screen support base 78. 80 is accommodated and provides a new screen 80, which is
Is transferred to the screen support base 78, and is positioned and fixed. In the screen storage device 24, a stocker capable of storing ten screens 80 vertically may be moved up and down by an elevator to transfer the screens 80.

Next, the screen cleaning device 26 will be described. As shown in FIGS. 7 and 8, the screen cleaning device 26 is located at a position adjacent to the screen accommodating device 24 of the frame 300 fixed on the base 30, above the screen transport device 22, and at the rising end position. It is provided at a height corresponding to the moved screen 80. The screen cleaning device 26, as shown in FIG.
When the ball screw 301 is rotated by the X-axis drive motor 302, the X-axis slide 306 is guided by the guide rail 304 and is moved in the X-axis direction, and the ball screw 307 is provided on the X-axis slide 306.
Has a Y-axis slide 312 (see FIG. 9) which is guided by the guide rail 310 and is moved in the Y-axis direction by being rotated by the Y-axis drive motor 308.

On the Y-axis slide 312, a long air ejector 316 and a solder suction unit 318 are provided rotatably about an axis parallel to the X-axis direction. A bracket 320 is fixed on the Y-axis slide 312,
U-shaped brackets 324 and 326 are fixed to upper and lower surfaces of a support member 323 fixed between the pair of side plates 322 of the bracket 320, respectively. The main body 328 of the air injector 316 has a tubular shape with a rectangular cross section, and is attached to a lower bracket 326 so as to be rotatable around an axis parallel to the X-axis direction by a shaft 332 on a lower bracket 326 fixed to the upper surface thereof. Have been. The main body 334 of the solder suction device 318 also has a tubular shape with a rectangular cross section. A bracket 336 fixed to the lower surface of the main body 334 is attached to an upper bracket 324 by a shaft 338 so as to be rotatable around an axis parallel to the X-axis direction. Have been.

A support plate 340 is fixed to the support member 323, and an air cylinder 342 for rotating an injector and an air cylinder 344 for rotating an aspirator are attached downward and upward, respectively.
48 is a bracket 350, 352 fixed to the rear end of the main body 328, 334 (the end opposite to the screen 80 side).
Are rotatably connected to the Therefore, the expansion and contraction of the piston rods 346 and 348 causes the air ejector 316 and the solder suction device 318 to rotate in opposite directions, and their tips (ends on the screen 80 side) approach and separate from each other. It will be. The rotation of the tip of the air ejector 316 and the tip of the solder sucker 318 approaching each other is defined by a stopper (not shown).

A cylindrical casing 358 is fixed to the upper surface of the tip of the main body 328 of the air injector 316.
An air injection nozzle 360 is disposed in the casing 358 so as to face upward. The air injection nozzle 360 is provided at a cylindrical connection portion 362 and at an upper end of the connection portion 362,
A thin box-shaped injection portion 364 having a width substantially equal to the width of the casing 358, and the injection portion 364 is formed with a large number of air injection openings formed on the upper surface thereof in a row in the X-axis direction. I have. The air injection nozzle 360 is provided in the main body 328, and has a pipe 366 having one end connected to the connection portion 362.
Tube 3 connected to tube 366 at the rear end of body 328
68 to a compressed air supply 370
The air supplied from the compressed air supply source 370 is injected from the air injection nozzle 360 directly above.

In the casing 358, a brush 374 is attached by an axis 376 adjacent to the air injection nozzle 360.
It is mounted rotatably about an axis parallel to the axial direction. The shaft 376 has a brush drive motor 378 (FIG. 10).
Of the pulleys 380 and 382 and the belt 38
4 and the brush 374 is rotated.

Further, the space inside the main body 328 is connected to a vacuum source 398 via a hose 388, a joint member 390, a hose 392, a solder collecting box 394 and a hose 396 connected to the rear end. Solder collection box 39
The space in 4 is divided into two chambers 402,
404 and a main body 328 in one chamber 402.
Is connected, and a vacuum source 398 is connected to the other chamber 404. The chambers 402 and 404 are connected at a lower portion, and the vacuum is supplied to the main body 328 through this portion.
6 is provided so that the cream solder sucked by the vacuum is not sucked into the vacuum source 398 as described later. The solder collection box 39
The lower part of 4 is a detachable receiving box 408 so that the creamy solder that has been sucked and accumulated can be discarded.

A cylindrical contact member 410 is fixed to the lower surface of the tip of the main body 334 of the solder suction device 318. A cylindrical cushioning member 412 is fitted to the contact member 410 so as to be relatively movable in the axial direction and not to come out. The space in the main body 334 also includes a hose 414, the joint member 390, a hose 392, a solder collecting box 394, and a hose 39.
6 to a vacuum source 398.

The screen printing machine is controlled by a control device 420 shown in FIG. The control device 420 is mainly composed of a computer, and includes the elevating motor 62 for raising and lowering the squeegee device 18 and the like, the squeegee device 18
Squeegee moving servomotor 96, first squeegee elevating air cylinders 114 and 116, second squeegee elevating air cylinder 180, scooping member elevating air cylinder 208, scooping member rotating air cylinder 272, screen cleaning X-axis drive motor 30 of device 26
2, the Y-axis drive motor 308, the injector rotation air cylinder 342, the suction unit rotation air cylinder 344, the compressed air supply source 370, and the vacuum source 398. 14, a screen transport device 22, and a screen storage device 24 are connected. These are controlled in accordance with a program stored in the ROM of the computer, and the transfer of the printed circuit board 10, positioning, screen printing, replacement of the screen 80, cleaning, recovery of creamy solder, and the like are performed.

Next, the operation will be described. When cream solder is printed on the printed circuit board 10 in the screen printing machine configured as described above, the screen positioning support device 16, the squeegee device 18, and the solder recovery device 20 are used.
Is at the lower end position, the screen 80 is positioned and fixed on the screen support base 78, and the creamy solder kneaded to have an appropriate viscosity is placed thereon. In the squeegee device 18, the slide 84 is located at one end in the X-axis direction in the printing area of the screen 80, and the first and second squeegees 112 and 188 and the scooping member 244 are provided.
Are at the rising end position. And the printed circuit board 1
0 is transported by the substrate conveyor 12 and the substrate support 3
8, the squeegee used for printing is lowered from the first and second squeegees 112 and 188 to contact the screen 80, and the slide 84 moves. The cream solder is printed on the printed circuit board 10.

If the first squeegee 112 is used for printing, air is supplied to the upper chambers of the air cylinders 114 and 116, and the lower chamber is released to the atmosphere. And brought into contact with the screen 80. At this time, since the weight of the first squeegee elevating unit 117 is exactly canceled by the spring 170 as described above, the first squeegee member 15
4 is brought into contact with the screen 80 only by the air pressure supplied to the air cylinders 114 and 116. Regardless of the weight of the first squeegee elevating unit 117, the first squeegee member 154 can be brought into contact with the screen 80 at a desired pressure, and a pressure gauge is provided between the air cylinders 114 and 116 and the air supply source. The air cylinder 1
It is possible to know the magnitude of the pressure of the air supplied to the screens 14, 116, and thus the contact pressure to the screen 80.

The first squeegee member 154 has two air cylinders 1 at positions separated in the longitudinal direction.
Since the screen 80 is brought into contact with the screens 14 and 116, the contact pressure can be adjusted arbitrarily. For example, even if the printed circuit board 10 and the screen 80 are inclined, the first squeegee member 154 rotates around the pins 164 and follows the pins 164, so that the first squeegee member 154 contacts the screen 80 with uniform pressure. In addition, the contact pressures at both ends of the first squeegee member 154 can be intentionally made different. Thereby, for example, when the diameter of the through-hole 83 formed in the screen 80 is extremely small and cream-like solder is difficult to enter, the contact pressure of the portion of the first squeegee member 154 moving on the through-hole 83 is reduced. By increasing the size, effects such as reliable printing of creamy solder can be obtained.

Note that it is not essential that the entire weight of the first squeegee elevating section 117 does not hang on the screen 80, but a part of the weight may be hung. When it is necessary to increase the contact pressure, the supply air pressure can be reduced by applying the weight of the first squeegee elevating unit 117 to the screen 80.

As described above, when the slide 84 moves and the solder paste is printed on one printed circuit board 10, the first squeegee 112 is raised, and after the printed circuit board 10 is discharged, a new one is printed. When the printed board 10 is brought into contact with the screen 80, the second squeegee member 190 is brought into contact with the screen 80 and printing is performed. At this time, the weight of the second squeegee elevating unit 1178 is not applied to the screen 80, and the second squeegee member 190 is brought into contact with the screen 80 only by the air pressure supplied to the second squeegee elevating air cylinder 180.
This is the same as the case of the first squeegee member 154.

When a predetermined number of prints have been made or when the type of the printed circuit board 10 changes, the screen 80 is replaced. If creamy solder remains on the replaced screen 80, the screen 80 is replaced. The cream solder hardens and causes dirt and clogging, and such creamy solder cannot be reused, resulting in waste. Therefore, at the time of screen replacement, first, the creamy solder remaining on the screen 80 is recovered by the solder recovery device 20.

At the end of printing, the cream solder is at one end in the squeegee moving direction in the printing area of the screen 80, and the first squeegee 112 and the scooping member 244 are above the cream solder. The first and second squeegees 112 and 188 are both at the rising end position,
The scooping member 244 is also at the raised end position. From this state, after the first squeegee 112 is lowered as shown by the solid line in FIG. 1 and the scooping member 244 is lowered as shown by the two-dot chain line, the first squeegee member 154 moves to the right by a small distance. Then, the first squeegee member 154 is brought into contact with the creamy solder. Subsequently, the pin 284 is fitted into the fitting hole 288, and the first squeegee 1
12 and the scooping member 244 are integrally connected, the scooping member 244 is rotated clockwise in FIG. 1, and moves toward the first squeegee 112 while pressing the creamy solder on the screen 80. I do.

The scooping member 244 includes a spring 256
As a result, the tip is urged downward so that the tip contacts the screen 80 before rotating until it approaches the first squeegee member 154, and the knife edge 268 is pressed against the screen 80. State. Therefore, when the scooping member 244 is further rotated, the knife edge 268 moves along the screen 80 and moves toward the first squeegee member 154 while scraping the creamy solder, as shown by the solid line. In a state where the knife edge 268 is close to the first squeegee member 154, the knife edge 268 enters between the cream-like solder stopped by the first squeegee member 154 and the screen 80 to scoop up the cream-like solder on the scooping surface 266. Considering the first squeegee member 154, the surface of the side opposite to the second squeegee member 190 rakes the creamy solder onto the scooping surface 266 and makes the scooping member 244 scoop. The scooping member 244 has a knife edge 268 formed by the first squeegee member 15.
4 and is not contacted with the first squeegee member 154, so that the rubber first squeegee member 154 is not damaged by the knife edge 268. .

After scooping, with the two chambers of the first squeegee elevating and lowering air cylinders 114 and 116 being both open to the atmosphere, the slide 84 is moved a small distance left in FIG. Moved at low speed towards. When the lifting plate 202 is lowered to the lower end, the second switching surface 222 of the switching plate 218 switches the lever 224 of the mechanical valve 216, and the lifting plate 202 moves up and down at a low speed. Therefore, the scooping member 244 and the first squeegee 11 connected by the pin 284
2 is moved slowly and obliquely upward, and the scooping member 244 rises while scraping the creamy solder on the screen 80. Rake member 2
44 and the first squeegee member 154, but the creamy solder has viscosity and
44 and the first squeegee member 154 are moved obliquely upward at a low speed, so that the creamy solder in the gap between the scooping member 268 and the first squeegee member 154 is scooped from the screen 80, and , Do not leak from between them.

If the first squeegee member 154 and the scooping member 244 are raised and moved by a small distance, the movement is stopped and the squeegee member 244 is raised at a high speed to the rising end position. In this state, the first squeegee member 154 and the scooping member 244 are separated from the screen 80, and the recovery of the creamy solder has been completed. After the creamy solder is scooped from the screen 80, the screen 80 is cleaned by the screen cleaning device 26 as described later.
After the cleaning, the screen 80 is conveyed by the screen conveying device 22 and accommodated in the screen accommodating device 24, and a new screen 80 is conveyed and positioned and fixed on the screen support base 78.

After fixing the new screen 80, the collected creamy solder is returned to the screen 80.
In this case, first, the solder collecting device 20
0, the first squeegee 112 and the scooping member 24 are moved to one end in the squeegee moving direction.
4 is lowered and brought into contact with the screen 80.
In this case, at the beginning of the lowering of the lift plate 202, the second switching surface 222 of the switching plate 218 switches the switching lever 224 of the mechanical valve 216 and is lowered at a high speed, but after descending a predetermined distance, the first switching surface 220 is switched. Since the lever 224 is switched and lowered at a low speed, the lever 224 can be slowly brought into contact with the screen 80, and there is no danger of damaging the screen 80.

After descending, the pin 284 is disengaged from the fitting hole 288 and the first squeegee 112 and the scooping member 24 are removed.
The connection with 4 is broken. Then, after the first squeegee 112 is raised, the second squeegee 188 is lowered to be brought into contact with the scooping surface 266 as shown by a two-dot chain line in FIG. Is rotated in the counterclockwise direction, the cream-like solder on the scooping surface 266 is removed from the second squeegee member 190.
Is scraped off on the screen 80. The cream-like solder is scraped down by the surface of the second squeegee member 190 on the side facing the first squeegee member 154, and then the second squeegee 188 and the scooping member 2
44 are respectively raised to the rising end positions, and the screen printing is started.

When screen printing is first performed by the second squeegee 188, it is not necessary to raise the second squeegee 188, and the screen printing is started as it is. This can be achieved by returning the creamy solder to the side where printing is started by the second squeegee 188.

As described above, the creamy solder remaining on the screen 80 is automatically collected by the solder collecting device 20 and automatically returned to the screen 80, so that the operator performs the collecting and returning operation. Work is performed more quickly than in the case, and the recovered cream-like solder is used for the next screen printing, and the waste of the cream-like solder can be eliminated. No more staining. Further, there is almost no creamy solder that remains on the screen 80 and hardens, and an effect of facilitating the cleaning of the screen 80 can be obtained.

As described above, in the screen 80 used for printing, as the number of times of printing increases, creamy solder adheres to the inner peripheral surface of the hole and remains, or the back surface (printed substrate 10).
Adheres to the surface of the printed circuit board 10 on which
May be soiled. Therefore, when a predetermined number of prints have been performed, when it is determined that the through-hole 83 is clogged by detecting the print result, when the screen 80 is replaced, or when the operation is temporarily interrupted, The screen 80 is cleaned by the screen cleaning device 26 at appropriate times.

When the screen is not cleaned, the screen cleaning device 26 is at a retracted position separated from the screen 80 as shown in FIG. During screen cleaning, the screen 80 is moved to the rising end position. And the screen cleaning device 2
6, the distal ends of the air ejector 316 and the solder suction device 318 are separated from each other as shown in FIG.
6 is located below the screen 80 and the solder suction device 318
Are moved in the X-axis direction and the Y-axis direction in a state where they are located above, and their leading ends are moved to a position on the screen 80 to be cleaned. After moving, as shown in FIG.
The tips are brought close to each other and sandwich the screen 80 from both upper and lower sides. At this time, the rotation of the air ejector 316 and the solder suction device 318 is regulated by a stopper (not shown), and the contact member 410 and the buffer member 412 relatively move at the tip of the solder suction device 318, thereby
It is avoided that the air ejector 316 and the solder suction device 318 pinch the screen 80 with excessive pressure. In this state, compressed air is supplied to the air injection nozzle 360 and is blown at right angles to the screen 80, so that the through holes 83 are formed.
The cream-like solder attached to the inner peripheral surface of the solder is blown up and removed.
8, is stored in the solder collecting box 394, and is collected in the receiving box 408. At the same time as the compressed air is sprayed, the brush 374 is rotated to remove the creamy solder adhered to the back surface of the screen 80, and the removed creamy solder is sucked in the main body 328 of the air ejector 316 by vacuum. It collects in the receiving box 408.

When the screen 80 is to be partially cleaned, the air ejector 316 and the solder suction device 318 are moved to a narrow area including the cleaning position, and the area is moved in the X-axis direction and the Y-axis direction. Cleaning is performed. Since only necessary parts can be cleaned, the amount of air suction and the supply of compressed air can be reduced, and the apparatus can be made compact and lightweight. If there is time, etc., the entire surface of the screen 80 may be cleaned. In that case, the air ejector 316 and the solder suction device 318 are reciprocated in the Y-axis direction to be cleaned. After each movement in one direction in the Y-axis direction, the tip of each of the air ejector 316 and the solder suction device 318 is separated from the screen 80, and after moving slightly shorter than the width of the air ejection nozzle 360 in the X-axis direction. The cleaning is performed by bringing the screen 80 into contact with the screen 80. After the cleaning, the air ejector 316 and the solder suction device 318 are opened and retracted, and the screen 80 is returned to the lower end position. The cream-like solder accumulated in the solder collecting box 394 is discarded after removing the receiving box 408.

When cleaning the screen 80,
A solvent may be sprayed before the cream solder is removed by the brush 374.

As is apparent from the above description, in this embodiment, the solder collecting device 20 corresponds to a printing agent collecting device, and the slide 84 constitutes a collecting device main body. Ma
In addition, the first squeegee elevating air cylinders 114, 116 and
And the second squeegee lifting air cylinder 180 is a squeegee.
An air cylinder for rotating a scooping member, which constitutes a lifting device
272 constitutes a scooping member rotating device,
The air cylinder 208 for elevating the member is used to lift the scooping member.
The nut 92, the screw shaft 94 and the squeegee
The movement servomotor 96 constitutes a squeegee moving device.
You. In addition, the controller 420
Making the ream-like solder scoop the scooping member 244
Lifting device and scooping member rotating device
The part that controls
From the scooping member 244 onto the screen 80
Squeegee elevating device and scooping member rotating device
Is a return control unit.

In the above embodiment, the case where the cream-like solder is collected when the screen is replaced has been described. However, even when printing is stopped for a long time, the cream-like solder is collected and returned to the solder container. The creamy solder is not left in the air for a long time, so that the creamy solder is not wasted and the yield can be improved.

In the above embodiment , when the creamy solder is collected, the first squeegee member 154 and the scooping member 2 are removed.
Although the gaps are left at the tips when the pieces 44 are brought close to each other, the pieces 44 may move until they touch each other or slightly cross each other to scoop up the cream solder.

[0057] Furthermore, a solder recovering apparatus 20,430 in the above embodiment has been provided with the squeegee device 18, but it may also be provided separately from the squeegee device 18. If so of their squeegee device 18 is lighter, it becomes possible to increase the printing speed by increasing the moving speed.

Although the screen cleaning device 26 is designed to clean the spot-shaped portion of the screen 80, the screen cleaning device 26 cleans the band-shaped portion parallel to the X-axis direction (or the Y-axis direction). Alternatively, the screen 80 may move in the Y-axis direction (or the X-axis direction), or the entire surface of the screen 80 may be cleaned at one time.

In addition, without departing from the scope of the claims, the present invention can be implemented in various modified and improved forms based on the knowledge of those skilled in the art.

[Brief description of the drawings]

FIG. 1 is a side view (partial cross section) showing a solder recovery device and a squeegee device of a screen printing machine according to one embodiment of the present invention.

FIG. 2 is a front view showing the squeegee device.

FIG. 3 is an enlarged front view (partial cross section) showing a main part of the squeegee device.

FIG. 4 is a front view showing an apparatus for switching a lifting speed of a scooping member in the solder collecting apparatus.

FIG. 5 is a front sectional view showing a part of a screen of the screen printing machine.

FIG. 6 is a front view of the screen printing machine.

FIG. 7 is a side view of the screen printing machine.

FIG. 8 is a plan view of the screen printing machine.

FIG. 9 is a front view showing a screen cleaning device provided in the screen printing machine.

FIG. 10 is a plan view of the screen cleaning device.

FIG. 11 is a diagram illustrating a control device that controls the screen printing machine, illustrating a portion that is deeply relevant to the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 Printed circuit board 18 Squeegee device 20 Solder recovery device 38 Substrate support 78 Screen support 80 Screen 84 Slide 92 Nut 94 Screw shaft 96 Squeegee moving servomotor 108 First squeegee unit 110 Second squeegee unit 112 First squeegee 114, 116 First squeegee elevating air cylinder 180 Second squeegee elevating air cylinder 188 Second squeegee 202 Elevating plate 208 Rake member elevating air cylinder 244 Rake member 266 Rake surface 272 Rake member rotating air cylinder 420 Control device

────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Takashi Iwazuki 19, Chauyama, Yamamachi, Chiryu-shi, Aichi Prefecture Inside Fuji Machinery Manufacturing Co., Ltd. 19 Fuji Machine Manufacturing Co., Ltd. (56) References JP-A-61-168997 (JP, A) JP-A-3-75147 (JP, A) JP-A-62-132643 (JP, A) JP-A-62-132643 4-358833 (JP, A) JP-A-5-24175 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B41F 15/08 B41F 15/40-15/44 H05K 3 / 12

Claims (3)

(57) [Claims] 1. A squeegee ski having a longitudinal shape of a squeegee device on a screen supported by the screen support pedestal, comprising a printing plate support, a screen support, and a squeegee device.
The squeegee moves in the direction perpendicular to the longitudinal direction by the squeegee moving device.
In a screen printing machine which prints a printing agent such as an adhesive or a creamy solder on a printing plate supported by a printing plate support base by being moved, the squeegee devices are moved together in the moving direction. Oppose
Two squeegees and these two squeegees
Separate from the screen at the point of contact with the screen
Squeegee elevating device to move to and from
It should be possible to print in both directions, and
Printing agent collecting device for collecting the printing agent placed on the printing agent
And a printing agent collecting device, the collecting device main body and the collecting device main body being parallel to the longitudinal direction of the squeegee.
Rake mount pivotally mounted about a pivot axis
Rotating the scooping member and the scooping member in the forward and reverse directions.
A skimming member rotating device, the skimming member rotating device, and the squeegee elevating device;
Controlling one of the two squeegees.
One of the squeegees
Mark the screen on the side facing the other squeegee
In a state where the movement of the printing material is prevented, the scooping member is
Touch the leading edge of the scooping member to the screen.
The square facing the one of the squeegees
To remove the printing agent that has been prevented from moving.
A scooping control unit for taking out and the other squeegee
Contact the scooping surface of the scooping member;
Of the other squeegee on the surface facing the one squeegee
With the printing agent on the scraping surface prevented from moving,
The printing material is scooped by rotating the take-off member in the opposite direction.
A return control unit for returning the take-up member onto the screen
And a control device having
Screen printing machine. 2. The two squeegees, the squeegee elevating and lowering.
Apparatus, said scooping member and said scooping member turn
A moving device is supported by the recovery device main body, and
The main body of the collecting device is moved by the squeegee moving device.
The screen printing machine according to claim 1, wherein 3. The collecting device body according to claim 1 , wherein
To move the screen up and down
2. The method according to claim 1 , further comprising a lifting member lifting device.
Or the screen printer according to 2.