Scraper device

Abstract

A squeegee device provided with a paste squeegee blade for preventing side leakage of solder paste, the squeegee device comprising: a traveling mechanism for reciprocating a traveling table; the two elevators are assembled on the walking platform; and a pair of squeegee heads assembled at the lower ends of the two elevators and provided with squeegee blades for rolling the solder paste on the mask, the squeegee heads having squeegee blades attached thereto, the squeegee blades being plate members for preventing side leakage of the solder paste from the squeegee blades, the squeegee blades being attached to both ends of a base rod supporting the squeegee blades, and the squeegee blades being attached to both ends of the base rod for supporting the squeegee blades. The spring member can move up and down in a state of being pressed from above by the spring member.

Description

Technical Field

[0001] The present invention relates to a scraper device having a scraper blade for preventing solder paste from leaking sideways. Background Art

[0002] In a screen printer, after a substrate is carried in by a conveying device and is held and arranged at a printing position under a mask, a scraper is used to print solder paste onto the substrate from the upper side of the mask through a printed pattern (through hole). At this time, the solder paste is pressed into the printed pattern while rolling on the mask by the scraper. On such a scraper head, scraper blades are provided at both ends to prevent the solder paste from being exposed laterally. The following patent document 1 discloses a method having Figure 7 The scraper device of the scraper knife shown. Figure 7 It is a perspective view showing the end of a scraper head of a conventional scraper.

[0003] The conventional scraper blade 100 is installed in a state where the position can be adjusted relative to the guide rail 102 in the direction perpendicular to the direction F of the movement of the scraper blade 101. The scraper blade 100 is formed of a thin metal plate, and the mounting portion 111 of the guide rail 102 is formed to be wide, and a strip-shaped side leakage prevention portion 112 with a narrower width extends from the mounting portion 111. The side leakage prevention portion 112 is composed of a rear portion 121 extending in the width direction behind the scraper blade 101, a lateral receiving portion 122 bent in the movement direction, and a side adjustment portion for receiving a larger amount of solder paste on the front side of the direction of movement. 123 composition. Prior art literature Patent Literature

[0004] Patent Document 1: Japanese Patent Application Publication No. 2001-121195. Summary of the invention Problems to be solved by the invention

[0005] However, the conventional scraper device is formed such that the scraper blade 100 extends from the mounting portion 111 to the side leakage prevention portion 112 and surrounds the end of the scraper blade 101. Therefore, the end of the scraper device becomes larger, and a space that does not interfere with the scraper blade 100 is required on the mask side. In addition, although the conventional scraper blade 100 can be adjusted in the width direction along the guide rail 102, it cannot be adjusted in the up and down direction for applying printing pressure, and therefore cannot follow the deflection of the scraper blade 101. Therefore, there is a possibility that a gap is generated between the scraper blade 100 and the mask, etc., causing leakage of solder paste.

[0006] Therefore, in order to solve the above-mentioned problems, an object of the present invention is to provide a squeegee device including a squeegee blade for preventing the side leakage of solder paste. Means for solving problems

[0007] The scraper device in one embodiment of the present invention comprises: a traveling mechanism that causes a traveling platform to reciprocate; two elevators assembled on the traveling platform; and a pair of scraper heads assembled on the lower ends of the two elevators, and having scraper blades for rolling the solder paste on the mask, the scraper heads being equipped with scraper knives, which are plate components that prevent the solder paste from leaking sideways from the scraper blades, being installed on the two ends of a base rod that supports the scraper blades, and being able to move up and down while being pressed from above by a spring component. Effects of the Invention

[0008] According to the above structure, the traveling platform is moved by the traveling mechanism, and the scraper blade of the scraper head assembled at the lower end thereof rolls the solder paste on the mask by descending one of the two elevators. The scraper head contacts and moves with the mask through the scraper blade that can move up and down while being pressed from above by the spring member, so that the solder paste can be prevented from leaking sideways from the scraper blade. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 The invention is a three-dimensional diagram showing a scraper device in a screen printing machine in a partial cross-section. Figure 2 It is a perspective view showing one embodiment of the scraper device. Figure 3 It is a side view showing the end of the scraper head in the X-axis direction, and in particular shows the scraper blade from the outside and the inside. Figure 4 It is shown by Figure 1 An enlarged view of the end of the scraper head surrounded by the circular frame B. Figure 5 1 is a three-view diagram showing an embodiment of a scraper. Figure 6 It is shown by Figure 1 An enlarged view of the end of the scraper head on the recovery plate enclosed by the circular frame B. Figure 7 It is a perspective view showing the end of a scraper head of a conventional scraper. DETAILED DESCRIPTION

[0010] Hereinafter, an embodiment of the squeegee device of the present invention will be described with reference to the drawings. The squeegee device of this embodiment is incorporated in a screen printing machine. Figure 1 is a three-dimensional diagram showing a scraper device in a screen printing machine in partial section. Figure 2 1 is a perspective view showing the scraper device.

[0011] First, the screen printer is used as a pre-process of the component execution machine for mounting electronic components on the printed substrate 10. In the screen printer, the printed substrate 10 carried in by the substrate conveying device is arranged under the mask 20, and the solder paste on the mask 20 is rolled by the squeegee device 1. As a result, the solder paste is spread in a manner of being pressed into the pattern holes formed in the mask 20, and a predetermined pattern based on the solder paste is printed on the printed substrate 10.

[0012] Such a scraper device 1 of a screen printing machine has a rod-shaped traveling platform 2 that is long in the width direction (X-axis direction) of the machine body, and is configured with a traveling mechanism that can reciprocate in the front-to-back direction (Y-axis direction) relative to the machine body of the screen printing machine. Specifically, sliding guides 11 are fixed to both ends of the traveling platform 2, and the sliding guides 11 are assembled to slide freely relative to a guide rod erected in the machine along the Y-axis direction. In addition, in this embodiment, the description is made with the width direction of the screen printing machine as the X-axis, the front-to-back direction as the Y-axis, and the up-down direction as the Z-axis.

[0013] A nut 12 constituting a ball screw mechanism is fixed to the traveling platform 2, and the screw shaft penetrates the nut 12 in the Y-axis direction. Therefore, the scraper device 1 is connected to a servo motor on the screw shaft that can rotate freely through a bearing, and the scraper device 1 can move to a specified position in the front-rear direction of the machine body by controlling the servo motor. The scraper device 1 is assembled with two elevators equipped with actuators such as electric cylinders in the central part of the traveling platform 2 that is longer in the width direction, and is covered by a cover 6. A pair of scraper heads 3 and 4 are assembled at the lower ends of the two elevators, which can be raised and lowered independently.

[0014] The scraper heads 3 and 4 are symmetrically configured in the front-to-back direction. On one side of the Y-axis direction is the scraper head 3 for rolling the solder paste, and on the opposite side is the scraper head 4 for rolling the solder paste. The scraper head 3 (hereinafter, the scraper head 4 is also the same when not specifically distinguished) has a scraper blade 15 for rolling the solder paste placed on the mask 20 on the mask 20. The paste-like solder paste is supplied linearly along the width direction on the mask 20, and the scraper blade 15 moves the solder paste in the front-to-back direction while pressing the solder paste against the mask 20.

[0015] Here, Figure 3 is shown in the X-axis direction by Figure 2FIG. 1 is a diagram showing the end of the scraper head 3 surrounded by a circular frame A, in particular showing the scraper from the outside and the inside. The scraper head 3 is fixed with a scraper blade 15 on a rod-shaped base rod 13 corresponding to the width dimension of the mask 20. The scraper blade 15 is a strip-shaped thin metal plate, and the scraper head 3 is fixed in a manner such that its scraper blade 15 is inclined relative to the base rod 13. The scraper blade 15 abuts against the inclined surface 131 of the base rod 13 and the upper end is screwed, and a cover member 14 overlaps on its upper end. Therefore, the scraper blade 15 is installed in a manner such that the lower end side in contact with the mask 20 is inclined toward the rear side relative to the travel direction Y1.

[0016] The scraper head 3 having the scraper blade 15 can be attached and detached relative to the elevator. Mounting blocks 18 are fixed at two locations on the upper surface of the base rod 13, and fastening bolts 19 are screwed on the upper surface of the mounting blocks 18. A support portion 21 with a U groove cut out is formed on the elevator side, and the fastening bolts 19 passing through the threaded portion are fastened to the support portion 21, thereby installing the scraper head 3 in a manner that the support portion 21 is clamped from above and below by the bolt head and the mounting block 18.

[0017] The scraper device 1 moves in the advancing direction Y1 by the scraper blade 15 in contact with the mask 20, and rolls the solder paste located in front of it so that it is pressed into the mask 20. At this time, it is necessary to prevent the solder paste from leaking sideways from the ends of the scraper blade 15, and therefore, scraper knives 17 are installed at both ends of the base rod 13 in a manner that the scraper blade 15 is clamped.

[0018] Here, Figure 4 It is shown by Figure 1 The enlarged view of the ends of the scraper heads 3 and 4 surrounded by the circular frame B. Figure 5 1 is a three-view diagram showing the scraper 17. Figure 5 As shown in the front view of the present invention, the scraper 17 is formed with longitudinal long holes 71 at two locations and is mounted on the end of the base rod 13 by bolts 23 passing through the long holes 71. Therefore, the scraper 17 can be displaced up and down relative to the base rod 13, but the upper end surface is pressed by the leaf spring 25 screwed to the upper surface of the base rod 13.

[0019] like Figure 5 As shown in the front view of the scraper 17, the scraper 17 is a roughly quadrilateral plate member, and an inclined portion 73 extending outward in the width direction of the body is formed on the front side. For example, consider the case where the scraper head 3 rolls the solder paste rolled by the scraper head 4 in the opposite direction. When the scraper head 4 rises at the stop position, as shown in FIG. Figure 4 As shown, the viscous solder paste 80 is lifted by the scraper blade 17 leaving the mask 20, and spreads outward as shown by the arrow after leaving. The inclined portion 73 extending in the width direction is a shape for collecting the solder paste that extends to the outside of the scraper blade 15 when the scraper head 3 rolls the solder paste 80.

[0020] The scraper 17 has a front taper 75 formed at the lower surface corner of the inclined portion 73 disposed on the front side of the traveling direction Y1. This is because the recovery plate 55 is arranged at the stop position where the rolled solder paste is stopped, and the scraper 17 can be smoothly placed on the recovery plate. Figure 1 As shown, in the screen printer, a recovery device 50 is provided at two locations at the front and rear ends of the printed substrate 10, and a recovery plate 55 with a tapered plate is configured to be able to rise and fall. Therefore, the solder paste rolled on the mask 20 by the squeegee head 3 will be placed on the recovery plate 55 on the side of the travel direction Y1.

[0021] Here, Figure 6 It is shown by Figure 1 FIG. 1 is an enlarged view of the ends of the scraper heads 3 and 4 on the recovery plate 55 surrounded by the circular frame B. The scraper 17 has a rear taper 77 formed at the corner of the lower surface on the side opposite to the travel direction Y1. This is a shape for preventing the solder paste attached to the scraper 17 from falling to the rear side. That is, in order to efficiently use the solder paste on the recovery plate 55, the scraper head 3 temporarily shifts its position to the rear and then moves to the travel direction Y1. This is to prevent the rear side of the scraper 17 with the solder paste attached at this time from being exposed to the rear side from the recovery plate 55.

[0022] When the scraper head 3 is lowered for printing, the scraper blade 15 to which printing pressure is applied is bent at the lower end. As described above, the scraper blade 17 can move up and down. Therefore, the scraper blade 17 is subjected to a reaction force by contacting the recovery plate 55 and the mask 20, and moves upward. That is, the scraper head 3 is constructed so that the scraper blade 17 is always in contact with the recovery plate 55 and the mask 20 during printing due to the force of the leaf spring 25, and the solder paste does not leak. In this regard, Figure 7 The scraper 100 of the conventional example shown has no degree of freedom in the up-and-down direction.

[0023] On the other hand, since the conventional scraper 100 has the rear portion 121, the solder paste can also be received at the rear side of the scraper blade 101. However, since the scraper 100 is structured to protrude to the rear side, it is not suitable for the narrow space on the mask. Therefore, in this embodiment, the scraper 17 formed as a small plate-shaped member is installed on the end surface of the base rod 13.

[0024] The scraper head 3 has a small gap between the scraper blade 15 and the scraper blade 17, so the solder paste leaks to the rear side. However, the scraper blade 17 with the solder paste attached is formed in a shape with a rear taper 77, so as described above, when the scraper head 3 retreats on the recovery plate 55, the attached solder paste does not fall out of the recovery plate 55. In addition, a chamfered portion 79 is formed on the outer side of the lower end portion of the scraper blade 17 to reduce the plate thickness downward, so that the attached solder paste can fall off well.

[0025] In the scraper device 1 having the above-mentioned structure, for example, the scraper head 4 is lowered by the descending action of the elevator and moves toward Figure 1 The solder paste is pressed into the mask 20 by the scraper blade 15 and rolled on the mask 20. The solder paste is placed on the recovery plate 55 that exceeds the printed circuit board 10. At this time, the scraper blade 17 resting on the recovery plate 55 rises against the elastic force of the leaf spring 25 and moves smoothly through the inclined portion 73 formed on the forward direction side.

[0026] After the printing process in one direction of the squeegee head 4 is completed, the solder paste on the recovery plate 55 is printed again by the squeegee head 3 on the opposite side. That is, the squeegee head 4 rises, while the squeegee head 3 on the opposite side slightly retreats in the travel direction Y1 and descends. The squeegee blade 15 and the scraper knife 17 contact the recovery plate 55, and the solder paste at the end of the extended inclined portion 73 also gathers and moves along the travel direction Y1. In addition, the solder paste rolled on the mask 20 similarly exceeds the printed substrate 10 and is placed on the recovery plate 55 on the opposite side.

[0027] As described above, according to the scraper device 1 of this embodiment, since the scraper blade 17 is formed by a plate member mounted on the end of the base rod 13, a compact structure can be formed. The scraper blade 17 is pressed by the leaf spring 25 in a state of being able to move up and down, and therefore, by always contacting the mask 20 and the recovery plate 55, it is possible to effectively prevent the solder paste from leaking sideways.

[0028] When the scraper blade 17 moves toward the recovery plate 55 while contacting the mask 20, the front tapered portion 75 is formed so that the scraper blade 17 can smoothly rest on the recovery plate. As a result, the solder paste being transported is less likely to leak from the scraper blade 17 than in the past. Moreover, even if some of the solder paste leaks, it will be collected by the inclined portion 73 of the scraper head 3 or 4 on the opposite side. As described above, the scraper device 1 is compactly constructed, so that the width of the recovery plate 55 can also be narrowed, and the solder paste attached to the paste scraper blade 17 will not fall from the recovery plate 55 by being exposed through the rear tapered portion 77.

[0029] Although one embodiment of the present invention has been described, the present invention is not limited thereto and various modifications can be made without departing from the gist of the present invention. Description of Reference Numerals

[0030] 1…scraper device, 2…traveling platform, 3, 4…scraper head, 13…base rod, 15…scraper blade, 17…paste scraper, 10…printed substrate, 20…mask, 55…recovery plate, 71…long hole, 73…inclined portion, 75…front tapered portion, 77…rear tapered portion, 79…chamfered portion.

Claims

1. A scraper device, comprising: The walking mechanism enables the walking platform to move back and forth; Two elevators assembled on the walking platform; and A pair of scraper heads are assembled at the lower ends of the two elevators and are provided with scraper blades for rolling the solder paste on the mask. The scraper head is equipped with a scraper blade, which is a plate component that prevents solder paste from leaking sideways from the scraper blade. The scraper blade is installed at both ends of a base rod that supports the scraper blade and can move up and down while being pressed from above by a spring component.

2. The scraper device according to claim 1, wherein: The scraper is formed with a longitudinal long hole, is mounted on the end of the base rod by a bolt passing through the long hole, and the upper end surface is pressed by a leaf spring screwed to the upper surface of the base rod.

3. The scraper device according to claim 1 or 2, wherein: The scraper is provided with an inclined portion extending outwardly on a front side surface in a traveling direction, and a front tapered portion is formed at a lower surface corner of the inclined portion.

4. The scraper device according to claim 1 or 2, wherein: The scraper has a rear tapered portion formed at a lower surface corner on the rear side relative to the traveling direction.

5. The scraper device according to claim 4, wherein: The scraper has a chamfered portion formed on the outer side of the lower end portion thereof so as to reduce the thickness of the plate downward.

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