JP5246775B2 - Screen printing machine - Google Patents

Description

  The present invention relates to a screen printing machine that applies a coating agent on a screen plate of a screen onto a printed board through a printing pattern hole formed in the screen plate by moving a squeegee.

In this type of screen printing machine, as disclosed in, for example, Patent Document 1, in order to prevent the coating agent from protruding laterally, protrusion preventing bodies are provided on both sides of the squeegee.
JP 2007-98738 A

  However, since anti-extrusion bodies are attached to both sides of the squeegee, it is easy for the coating agent to accumulate on the traveling side of the squeegee and between the squeegee and the extrude prevention body. The squeegee and the squeegee unit provided with the protrusion prevention body have to be removed from the printing press, which is a troublesome work for the operator.

  Accordingly, an object of the present invention is to enable easy cleaning of a squeegee and a protrusion prevention body.

For this reason, in the first aspect of the present invention, in the screen printing machine that applies the coating agent on the screen plate of the screen to the printed circuit board through the printing pattern hole established in the screen plate by moving the squeegee, the interval adjustment is performed. Both ends of the anti-extrusion body are provided on the opposing screen frame that supports the screen plate by a member and is provided with an anti-extrusion plate that prevents the coating agent from protruding laterally by a height adjusting member. It is characterized in that each is attached so as to be movable.

According to a second invention, in the first invention, the protrusion preventing plate is fixed to the protrusion preventing body by a plurality of the height adjusting members at different positions in the length direction .

  The present invention can easily clean the squeegee and the protrusion preventing body.

  Hereinafter, specific embodiments of the present invention will be described with reference to the drawings. The screen printing machine applies a solder paste, which is a fluid (not shown), as a coating agent to a desired pattern so that chip-shaped electronic components are mounted on the upper surface of the printed circuit board P conveyed from an upstream device (not shown). .

  The printed circuit board P is placed on a placement table (not shown) in a state of being positioned by a positioning mechanism (not shown). This mounting table is moved up and down by a vertical movement mechanism by a moving table, and this moving table is movable in the horizontal direction by the moving mechanism, and receives a printed circuit board P from the upstream device and positions it on the mounting table. Moved to the printing station.

  1 is a plan view of the screen, FIG. 2 is a sectional view taken along the line AA of FIG. 1, and FIG. 3 is a sectional view taken along the line BB of FIG. 1, wherein 1 is a screen supported by a screen support unit. The screen plate 2 is provided with a print pattern hole (opening) formed corresponding to a desired circuit pattern of the substrate P, and a screen frame 3 surrounding the screen plate 2.

  The screen frame 3 of the screen 1 is formed to have a rectangular shape in plan view from one pair of opposed screen frames 3A, 3A and the other pair of opposed screen frames 3B, 3B.

  Then, the pair of squeegees 5 are alternately lowered and moved in the front-rear direction (up and down direction on the paper surface of FIG. 1) by the reciprocating mechanism between the pair of screen frames 3A and 3A. In the screen 1, the distance between the pair of protrusion preventing bodies 8 can be adjusted by the distance adjusting member.

  In other words, a horizontally long guide 6 extending in the horizontal direction is formed on the opposing inner side surfaces of the screen frames 3A and 3A, and a pair of protrusion preventing bodies 8 provided with a protrusion preventing plate 7 for preventing the solder paste from protruding to the side. Is moved horizontally. Further, each guide 6 forms a storage space S on the inner surface of the screen frame 3A, and a horizontally elongated guide adjusting port 10 is formed on the front surface 9 forming the space S. Further, the bolt 12 is screwed to the nut 11 accommodated in the space S through the opening formed in the flat plate portion 8A at both ends of the protrusion preventing body 8 and the guide adjusting port 10 of the guide 6 so that the screen frame Each protrusion prevention body 8 is fixed at an appropriate position along 3A and 3A.

  And the protrusion prevention board 7 is attached to each protrusion prevention body 8 so that adjustment is possible by a height adjustment member to an up-down direction. That is, the outer shape of the vertical section of the intermediate portion of the protrusion prevention body 8 is a quadrangle, and the protrusion prevention plate 7 having a substantially U-shaped cross section is formed on the outer surface, upper surface, and inner surface of the intermediate portion of the protrusion prevention body 8. It is arranged so as to be partly movable and movable up and down, and is provided in the vertically long mounting elongated holes 7B and 7B provided in the outer side surface 7A of the protrusion preventing plate 7 and the attachment hole provided in the protrusion preventing body 8. Each screw 15 is inserted, and the protrusion prevention plate 7 is fixed to the protrusion prevention body 8 at an appropriate height position.

  It should be noted that the protrusion preventing piece 7C that hangs down on the inner side surface of each protrusion preventing plate 7 is inclined obliquely so as to become inward as it goes downward from the upper part of the inner side surface of the protrusion preventing body 8, that is, each protrusion preventing plate. 7C are inclined so as to approach each other, and the lower end of the protrusion preventing piece 7C hangs down below the protrusion preventing body 8 and hangs down above the screen plate 2 of the screen 3. To do.

  Further, the protrusion preventing piece 7C is made of a material having elasticity. When the squeegee 5 is not positioned between the protrusion preventing pieces 7C, 7C, the distance between the protrusion preventing pieces 7C, 7C is the longitudinal direction of the squeegee 5. Although it is disposed slightly shorter than the length, when one squeegee 5 descends so as to press-contact with the screen plate 2 during printing and is positioned between the protrusions 7C and 7C, the squeegee 5 is elastic. Against this, it is sandwiched while widening the distance between the two protruding prevention pieces 7C, 7C.

  The squeegees 5 and 5 are attached to a squeegee base (not shown) during screen printing, and can be alternately moved up and down by a vertical drive source, and the reciprocating mechanism causes the squeegee base to move up and down in the plane of FIG. Is reciprocated.

  The operation of the screen printing machine configured as described above will be described below. First, when the printing operation is started, the mounting table positioned on the positioning station side is first lower than the transfer level of the supply conveyor, and the printed circuit board P transferred from the upstream device by the supply conveyor is mounted on the mounting table. When positioned above, the supply conveyor is stopped.

  Next, the mounting table is raised from the transport level by the vertical drive source, and the printed circuit board P is mounted on the mounting table. The mounting table on which the printed board P is mounted is moved to the printing station by the moving mechanism. Then, the left squeegee 5 shown in FIG. 3 is lowered onto the screen plate 2 by the drive of the vertical drive source in a state adjusted by the angle adjusting mechanism to a desired squeegee angle.

  In this case, when the left squeegee 5 is lowered so as to come into pressure contact with the screen plate 2, it is lowered while increasing the distance between the two protrusion preventing pieces 7C, 7C against the elastic force of the protrusion preventing pieces 7C, 7C. (See FIGS. 4 and 5).

  Then, the squeegee 5 is pressed against the screen plate 2, and the solder paste supplied on the screen plate 2 by moving from the left to the right in FIG. Printing is performed on the printed circuit board P through the printing pattern holes provided in the board 2.

  As described above, when printing is performed, the squeegee 5 is lowered onto the screen plate 2 by the drive of the vertical drive source, and the squeegee 5 is grounded and pressed on the screen plate 2. And as shown in FIG. 5, it can prevent that a solder paste protrudes to the side of the squeegee 5 with the protrusion prevention piece 7C of the protrusion prevention board 7 which will be located in the both sides of the said squeegee 5. FIG.

  When printing in the forward direction is completed, the left squeegee 5 is lowered by driving the vertical drive source, and the right squeegee 5 is similarly lowered by driving the corresponding vertical drive source to print in the backward direction. To raise the squeegee 5. After the printing is completed, the positioning of the mounting table is released, the mounting table is lowered below the transport level, and the printed board P is discharged by a discharge conveyor (not shown). After the substrate P is discharged, the mounting table is returned from the printing station to the positioning station by the moving mechanism to prepare for the next supply of the printed substrate P. Thereafter, the printing operation is continued in the same manner.

  When the model of the printed circuit board P is switched, the screen 1 corresponding to the printed circuit board P to be switched is attached to the screen support unit instead of the screen 1 supported by the screen support unit. In this case, the bolts 12 and the nuts 11 are loosened, and the two protrusions 8 are moved along the screen frames 3A and 3A via the guide adjustment port 10 of the guide 6 according to the size of the printed circuit board P after the model change. . Specifically, the two protrusion preventing bodies 8 are moved so that the distance L1 between the two protrusion preventing pieces 7C and 7C as shown in FIG. 2 becomes a distance L2 as shown in FIG. 6 shorter than the distance L1. .

  After this movement, the protrusions 8 are fixed at appropriate positions along the screen frames 3A and 3A by tightening the bolts 12 and the nuts 11. As described above, according to the size of the squeegee 5 in the longitudinal direction, it is possible to easily adjust the mounting positions of the protrusions 8 to the screen frames 3A and 3A. Can be attached in position.

Further, if necessary, the screws 15 are loosened, and the protrusion prevention plate 7 is moved either up or down while the attachment elongated holes 7B and 7B and the screws 15 are along, so that the protrusion prevention bodies 8 are moved. The protrusion prevention plate 7 is adjusted in the vertical direction, and the screws 15 are tightened after the adjustment, whereby the protrusion prevention plate 7 is fixed to the protrusion prevention body 8 at an appropriate height position. In this case, FIG. 7 shows an example in which the protrusion prevention plate 7 is moved upward and adjusted with respect to the protrusion prevention body 8, and according to this embodiment, the height position adjustment is performed on the protrusion prevention plate 7. Can be done easily.

  In the past, anti-extrusion bodies were attached to both sides of the squeegee, so the coating agent tends to accumulate between the squeegee's progress side and between the squeegee and the extrude prevention body. The squeegee and the squeegee unit provided with the protrusion preventing body have to be removed from the screen printing machine, which has been a troublesome operation for the operator. According to the present invention, the opposing screen frame that supports the screen plate is used. In addition, since the protrusion preventing body for preventing the coating agent from protruding to the side is attached, the squeegee and the protrusion preventing body can be easily cleaned.

  In the above-described embodiment, the case where the present invention is applied to a screen printing machine that performs printing by moving the screen and the printed circuit board stationary and moving the squeegee is described. However, the screen and the substrate to be printed are moved stationary. The present invention can also be applied to a screen printing machine.

  Although the embodiments of the present invention have been described above, various alternatives, modifications, and variations can be made by those skilled in the art based on the above description, and the present invention is not limited to the various embodiments described above without departing from the spirit of the present invention. It encompasses alternatives, modifications or variations.

It is a top view of a screen. It is AA sectional drawing of FIG. It is BB sectional drawing of FIG. It is AA sectional drawing of the state of FIG. 1 of the state which the squeegee fell. It is BB sectional drawing of the state of FIG. 1 in the state which the squeegee fell. It is AA sectional drawing of the state of narrowing between both protrusion prevention bodies. It is BB sectional drawing of the state of FIG. 1 of the state which raised and attached the protrusion piece.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Screen 2 Screen board 3 Screen frame 5 Squeegee 6 Guide 7 Protrusion prevention board 7B Installation long hole 7C Protrusion prevention piece 8 Projection body 10 Guide adjusting port 11 Nut 12 Bolt 15 Screw S Space

Claims (2)

In a screen printing machine that applies a coating agent on a screen board of a screen to a printed circuit board through a printing pattern hole provided in the screen board by moving a squeegee, the screen board is supported by a spacing adjusting member. A protruding prevention plate for preventing the coating agent from protruding to the side is provided on the opposing screen frame so that the both ends of the protruding prevention body provided to be adjustable in the vertical direction by the height adjusting member are movably attached. A screen printer. The screen printing machine according to claim 1 , wherein the protrusion preventing plate is fixed to the protrusion preventing body by a plurality of the height adjusting members at different positions in the length direction .

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