JPH0658991B2 - High viscosity cream solder printing device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a printing apparatus for performing pattern printing on a printed electronic board by using high-viscosity cream solder.

[Conventional technology]

As shown in FIG. 8, the conventional cream solder printing device is
Above the table 1 on which the printed electronic substrate P and the print mask m are installed, a movable table 3 which is reciprocally moved along a guide rail 2 parallel to the table surface is provided, and an air cylinder 4 is provided below the movable table 3 by an air cylinder 4. By providing a squeegee 5 with a tilt stop that is moved up and down, and moving the squeegee 5 in the direction A while being pressed against the print mask surface with a constant pressure,
The cream solder C is poured into the pattern holes h of the print mask m to print a pattern on the printed electronic substrate P.

This conventional printing device is used for printing low-viscosity cream solder, and when it is applied to high-viscosity cream solder printing, the following problems occur (note that high-viscosity cream solder is used). The reason is to reduce the fluidity of the cream solder and prevent the solder flow at the time of mask removal when printing as a thick solder layer,
It is necessary to print thick cream solder and increase the welding strength of electronic components).

That is, when the cream solder C has a high viscosity, the high-viscosity cream solder does not flow like the low-viscosity cream solder, and therefore, even if the squeegee 5 is pressed,
There is a problem that the upper surface of the print mask m simply slides sideways, and the mask pattern hole h does not enter well (the pattern is not printed). Further, the high-viscosity cream solder C firmly adheres to the squeegee 5, and There is also the problem of non-printing that does not come down to.

By the way, instead of the squeegee 5 of the conventional device, a printing device using a printing roller 6 and a scraper 7 as shown in FIG. 9 can be considered. (Not known). This printing apparatus has a table 1 on which a printed electronic substrate P and a printing mask m are placed in a state as shown in the figure, and a movable table 3 provided above the table 1 so as to be capable of reciprocating along a guide rail 2 parallel to the table surface. , The air cylinders 8 and 9 arranged below the movable table 3 so as to approach the movable table moving direction.
When the high-viscosity cream solder C is printed by using the roller-scraper type printing device, the printing roller 6 and the scraper 7 are individually moved up and down by a predetermined stroke by the operation of Causes the following problems.

[Problems to be Solved by the Invention] In the state where the printing roller 6 is lowered by the operation of the air cylinder 8 and is pressed onto the printing mask m (at this time, the scraper 7 is in a standby state for raising), the movable base is 9 is moved by the forward movement of FIG. 3 in the direction of FIG. 9A to perform printing, the contact frictional force of the printing roller 6 on the mask surface is reduced by the effect of the cream solder C, and the rotation of the roller 6 is stopped. Therefore, solder flow does not occur,
The cream solder C slips on the print mask m. In this state, the cream solder C does not flow into the mask pattern hole h and is not printed on the printed electronic board P.

The scraper 7 descends as shown in FIG. 10 by the operation of the air cylinder 9 when the printing roller 6 rises at the printing end position, and the movable base 3 moves backward to return the scraper 7 to the solder mask on the printing mask m. It has the function of evenly scraping a continuous surface (uneven surface) so as to have a uniform thickness. When the solder is smoothed by the scraper 7, the printing roller 6 stops rotating in a state of being raised to the scraper approaching position. Therefore, the pile of cream solder C scraped up by the scraper 7 is enlarged between the scraper 7 and the roller 6 as shown in FIG. State), so that when the printing roller 6 and the scraper 7 return to the state shown in FIG. 9 and perform the next printing, the cream solder C is placed on the printing mask m. It doesn't come down to, and the problem of printing failure occurs.

[Means for solving problems]

In order to solve the above-mentioned problems, the present invention has a roller scraper type printing apparatus shown in FIGS. 9 and 10 in which a pinion gear for rotating the printing roller is engaged with the pinion gear when the printing roller descends. A lower rack and an upper rack, which is opposed to and spaced apart from the lower rack with a pinion gear disengagement interval, meshes with the pinion gear when the printing roller rises, and the movable table moves forward with the scraper rising and the printing roller lowered. During the printing operation, the print roller is forcibly rotated in the moving direction in synchronization with the moving speed of the movable table, and the movable table is moved backward while the printing roller is raised and the scraper is lowered. At this time, the printing roller is forced to rotate in the same direction as the rotation direction during printing in synchronization with the moving speed of the movable table. It is characterized in that the the.

[Action]

By forcibly rotating the printing roller in the moving direction in synchronization with the moving speed of the movable table, a solder flow of roller winding toward the mask surface direction is generated in the high-viscosity cream solder, which causes the high-viscosity cream solder to print. It is pushed into the pattern hole of the mask and flowed in, and solder printing of a predetermined pattern is performed.

Further, when the solder is leveled by the scraper, the printing roller raised to the scraper approaching position is forcibly rotated in the same direction as the roller rotation direction at the time of printing in synchronization with the return movement speed of the movable table, so that the scraper is scraped up. A solder flow of roller winding toward the mask surface is generated in the pile of cream solder, which prevents strong adhesion of high viscosity cream solder to the scraper and jamming of solder in the scraper / roller gap, It is possible to ensure a smooth solder flow during the printing operation.

〔Example〕

Hereinafter, an embodiment of the device of the present invention will be described with reference to the drawings of FIGS. 1 to 7. In the figure, 11 is a table for setting a printed electronic substrate P and a print mask m in a superposed state as shown in FIG. Above the table 11, there is provided a movable table 13 which is reciprocally moved by the operation of the fluid pressure cylinder 10 along a guide rail 12 parallel to the table surface. This movable table
A printing roller 16 and a scraper 17, which are individually moved up and down with a constant stroke in the vertical direction by the operation of the fluid pressure cylinders 18 and 19, are arranged below the 13 in a state of approaching the movable table moving direction. There is.

20 is a second member on the outer side of the one-sided shaft support 21 of the printing roller
This is a pinion gear for rotation drive of the printing roller, which is rotatably supported as shown in the figure. The toothed pulley attached to this pinion gear shaft 22.
23 and toothed pulley mounted on the shaft end of the printing roller 16
Toothed belt 25 is hung on 24 as shown in FIG. 26
Is a lower rack which is arranged at one side position with respect to the moving direction of the movable table of the table 11 and in which the pinion gear 20 meshes as shown in FIG. 6 when the printing roller 16 descends as shown in FIG.
Reference numeral 27 denotes an upper rack which is opposed to and spaced from the lower rack 26 while keeping a pinion gear disengagement distance b, and the pinion gear 20 meshes as shown in FIG. 7 when the printing roller 16 rises as shown in FIG.
The upper rack 27 and the lower rack 26 have rack teeth 27a, 26a having a length corresponding to the moving stroke of the movable body, and the pin-on gear 2
In order to prevent a meshing failure of 0, the link type rack operating mechanism 28 is moved in the front-rear direction by a small range. The rack operating mechanism 28 is a vertical rack.
Link connection members 31 and 3 fixed to both end connectors 29 and 30 of 27 and 26
2 ・ 31a, 32a, and one end is attached to the table side plate 11a by the rotation fulcrum shafts 33, 3
4, 33a, 34a is pivotally supported and the other end is a link connecting member 31, 32, 31a, 3
It is composed of a pair of front and rear parallel link members 35, 36, 35a, 36a which are rotatably pin-connected to 2a, and an operating cylinder 37 whose rod end is connected to this one link member 36a.
(See FIG. 1 and FIG. 6) Next, using the printing device, a high-viscosity cream solder C is obtained.
A method of pattern-printing on the printed electronic substrate P will be described in order of steps.

First step: A printed electronic substrate P and a print mask m having a pattern hole h are superposed on the table 11 as shown in FIG. 4, and a highly viscous cream solder C is placed on the print mask descending position on the print mask m. Put up in a draft.

Second step ... The printing roller 16 is lowered by the operation of the cylinder 18, and the printing roller 16 is pressed against the upper surface of the printing mask m with a constant pressure. At this time, the pinion gear 20 for rotating the roller engages with the lower rack 26 as shown in FIG.

Third step: In the state shown in FIG. 4 in which the roller 16 is lowered and the scraper 17 is raised, the movable table 13 is moved forward in the direction of FIG.
The print roller 16 can be moved by the engagement of the lower rack 26 and the lower rack 26.
In synchronism with the moving speed of 13, forcibly rotate clockwise in Fig. 4. The forced rotation of the printing roller 16 causes the high-viscosity cream solder C to have a solder flow of roller entrainment as shown by the arrow (a) in FIG. 4 directed toward the mask surface, whereby the high-viscosity cream solder C is produced. Is pushed into the pattern hole h of the print mask m and flows in, and solder printing of a predetermined pattern is performed.

Fourth step: At the movement limit position of the printing roller 16, the roller 16 is moved up by the operation of the cylinder 18, and the scraper 17 is moved down by the operation of the cylinder 19 so as to hit the mask surface. At this time, the pinion gear 20 for rotating the roller engages with the upper rack 27 as shown in FIG.

Fifth step ... In the state shown in FIG. 5 in which the roller 16 is raised and the scraper 17 is lowered, the movable table 13 is moved backward in the direction of FIG. The upper discontinuous solder surface (uneven surface) is scraped evenly with the scraper 17 to a uniform thickness. During this solder leveling operation, the pinion gear 20 and the upper rack 27 mesh with each other to synchronize the printing roller 16 with the return moving speed of the movable table 13 in the clockwise direction in FIG. Forced rotation in the same direction). The forced rotation of the printing roller 16 causes a solder flow of roller winding as shown by an arrow line (b) in FIG. 5 toward the mask surface in the pile of the cream solder C scraped up by the scraper 17, thereby It prevents the high-viscosity cream solder C from being firmly attached to the scraper 17 and being jammed in the space between the scraper and the roller.

Sixth step: When the above-described solder leveling operation is completed, both the printing roller 16 and the scraper 17 are raised, the print mask m is removed, and the pattern-printed printed electronic substrate P is removed from the table 11.

〔The invention's effect〕

Since the printing device for high-viscosity cream solder of the present invention is as described above, it is possible to obtain high-viscosity cream solder by forcibly rotating the printing roller in the traveling direction in synchronization with the moving speed of the movable table during solder printing. A roller-wrapped solder flow toward the mask surface direction can be generated, which allows the high-viscosity cream solder to be reliably pushed into the pattern hole of the printing mask and flow in, and good solder printing of a predetermined pattern can be performed. .

Further, when the solder is leveled by the scraper, the printing roller raised to the scraper approaching position is forcibly rotated in the same direction as the roller rotation direction at the time of printing in synchronization with the return movement speed of the movable table, so that the scraper is scraped up. It is possible to generate a solder flow of roller winding toward the mask surface in the pile of cream solder, which prevents the sticking of high viscosity cream solder to the scraper and the jamming of solder in the scraper-roller gap. It is possible to secure a smooth solder flow in the next printing operation.

[Brief description of drawings]

FIG. 1 is an overall perspective view showing a printing apparatus for high-viscosity cream solder according to an embodiment of the present invention, FIG. 2 is a perspective view of a main part of the apparatus, and FIG. 3 is a perspective view of a printing roller rotation driving section. FIGS. 4 and 5 are schematic explanatory views for explaining the printing method, FIG. 6 is a state diagram in which a pinion gear for rotating the printing roller is engaged with the lower rack, and FIG. 7 is a diagram in which the pinion gear is engaged with the upper rack. FIG. 8 is an explanatory view showing a conventional squeegee type printing apparatus, and FIG. 9 is an explanatory view showing a roller scraper type printing apparatus assumed by the present inventor.
FIG. 10 is a state diagram of the printing apparatus when the solder is leveled. P ... Printed electronic board, m ... Printing mask, h ... Mask pattern hole, C ... High-viscosity cream solder, 10 ... Cylinder for moving platform, 11 ... Table, 12 ... Guide rail, 13 ... Movable platform, 16 ... Printing roller , 17 ... scraper, 18 ... printing roller vertical movement cylinder, 19 ... scraper vertical movement cylinder, 20 ... printing roller rotation drive pinion gear, 21 ... printing roller shaft support, 26 ... lower rack, 27 ... upper rack, b ... Pinion gear separation distance between the upper and lower racks.

Continuation of the front page (56) Reference JP 62-57764 (JP, A) JP 61-168997 (JP, A) Actual opening 61-143760 (JP, U) Actual opening 61-72843 (JP , U) Japanese Patent Publication 3-3542 (JP, B2)

Claims (1)

[Claims] 1. A table on which a printed electronic substrate and a printing mask are placed in a superposed state, a movable table provided above the table so as to be capable of reciprocating along a guide rail parallel to the table surface, and a lower side of the movable table. The printing roller and scraper, which are arranged close to the movable table in the direction of movement of the movable table, are individually moved up and down by a constant stroke in the vertical direction by an actuating means such as a fluid pressure cylinder, and the outer portion of the printing roller shaft support. A pinion gear for driving the rotation of the printing roller and a rack having a length corresponding to a moving body moving stroke which is arranged at a position on one side of the table with respect to the moving direction of the movable table and meshes with the pinion gear when the printing roller descends. The lower rack having teeth and the lower rack and the pinion gear are opposed to each other with a disengagement distance kept therebetween and the pinion is provided when the printing roller is raised. Ya printing device with high viscosity cream solder formed by and a rack on which meshes.