JP2003220684A - Screen printing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a screen printing apparatus capable of certainly detecting the clamp detachment of a substrate plate. <P>SOLUTION: In the screen printing apparatus for bringing a mask plate 11 into contact with the substrate plate 10 and printing cream solder on the substrate plate 10 by a squeegee unit 12, in such a state that the side ends of the substrate plate 10 are held from both sides by the clamp surface in a substrate plate positioning part 1, the detached state of the side ends of the substrate plate 10 from a clamp surface is detected by detecting a dog member 22 moving along with a clamper 9 by a sensor 23. By this constitution, operation abnormality due to the continuation of printing operation in such a state that the substrate plate 10 is detached from a clamped state can be prevented. <P>COPYRIGHT: (C)2003,JPO

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a screen printing apparatus for printing paste such as cream solder or conductive paste on a substrate. In an electronic component mounting process, screen printing is used as a method for printing paste such as cream solder or conductive paste on a substrate. In this method, a mask plate provided with a pattern hole in accordance with a printing target portion is brought into contact with the substrate, a paste is supplied onto the mask plate, and a squeegee is slid on the substrate through the pattern hole. The paste is printed. In screen printing, it is necessary to keep the substrate in close contact with the mask plate and to maintain the position correctly so as not to cause a horizontal displacement. For this reason, the substrate positioning part for positioning and holding the substrate is provided with a clamping mechanism for holding the position by sandwiching the side edge of the substrate from both sides together with a lower receiving part that contacts and supports the lower surface of the substrate. Yes. The plate separation for separating the mask plate from the substrate during or after the printing operation is performed with the substrate clamped. However, since the clamping is performed by sandwiching the side end surface of the substrate with the clamping surface, the substrate is likely to be out of the clamped state. Then, the substrate out of the clamped state remains in close contact with the lower surface of the mask plate, and if the next substrate is carried in this state, it causes a problem such as substrate cracking. As described above, the conventional screen printing apparatus has a problem in that it cannot detect that the substrate is out of the clamped state, and abnormal operation occurs due to the release of the clamp. SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a screen printing apparatus that can reliably detect the unclamping of a substrate. According to a first aspect of the present invention, there is provided a screen printing apparatus in which a mask plate provided with a pattern hole is brought into contact with a substrate and paste is supplied onto the mask plate to slide a squeegee. A screen printing apparatus that prints a paste on a substrate through the pattern hole, and includes a substrate transport unit that transports the substrate, a substrate positioning unit that holds and positions the transported substrate, and the substrate The positioning unit includes clamping means for sandwiching and holding the side end portion of the substrate from both sides by the clamping surface, and clamping disengagement detection means for detecting a state in which the side end portion of the substrate is detached from the clamping surface. According to the present invention, the clamping means for holding the side edge portion of the substrate sandwiched from both sides by the clamping surface in the substrate positioning portion, and the detection of clamping disengagement for detecting the state where the side edge portion of the substrate is detached from the clamping surface Means for reliably detecting the unclamping of the substrate,
It is possible to prevent an abnormal operation caused by continuing the printing operation while the substrate is out of the clamped state. DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a side view of a screen printing apparatus according to an embodiment of the present invention, FIG. 2 is an explanatory view of a clamp driving mechanism of the screen printing apparatus according to an embodiment of the present invention, and FIGS. It is a side view of the screen printing apparatus of an embodiment. First, the structure of the screen printing apparatus will be described with reference to FIG. In FIG. 1, a substrate positioning unit 1
Is configured by stacking a Z-axis table 4 on a moving table composed of a Y-axis table 2 and an X-axis table 3. The upper surface on the Z-axis table 4 serves as a receiving portion that holds and receives the substrate 10 on which electronic components are mounted. By driving the substrate positioning unit 1, the position of the substrate 10 at the time of screen printing can be adjusted by moving the substrate 10 held by the lower receiving unit in the X direction (direction perpendicular to the paper surface) and the Y direction. A pair of transfer rails 8 are horizontally disposed above the substrate positioning unit 1, and the transfer rails 8 receive the substrate 10 received from the upstream substrate transfer apparatus to the substrate positioning unit 1 in the X direction. Transport in the direction perpendicular to the page. The transport rail 8 serves as a substrate transport means. The transport rail 8 includes a clamper 9, and the clamper 9 is driven in the horizontal direction by a clamp drive mechanism 20, so that the substrate positioning unit 1
The side end portion of the substrate 10 positioned on the side is sandwiched and held. Next, referring to FIG. 2, the clamp drive mechanism 2
0 will be described. In FIG. 2A, each pair of transport rails 8 includes a clamper 9, and one clamper 9 is coupled to a rod 21a of a cylinder 21 and is movable in the horizontal direction. In a state where the rod 21a protrudes, the clamper 9 is at a position away from the side end portion of the substrate 10 and is in a clamp release state. Further, as shown in FIG.
As a returns, the movable clamper 9 moves in the direction of the arrow a, and the side end portions of the substrate 10 are clamped by sandwiching the side end portions of the two clampers 9 (clamp surfaces). The clamper 9 and the clamp driving mechanism 20 serve as clamping means that sandwich and hold the side end portion of the substrate 10 from both sides in the substrate positioning portion 1 by the clamping surfaces. A dog member 22 having a shape extending rightward is attached to the movable clamper 9, and the cylinder 2
As the clamper 9 is moved horizontally by the operation 1, the dog member 22 is also moved horizontally. A sensor 23 is fixedly arranged at the moving height of the dog member 22, and the sensor 23 is arranged to detect the dog member 22 in a state where the clamper 9 moves inward beyond the normal substrate clamp position. . FIG. 2 (c) shows a state in which the substrate 10 is not normally clamped by the clamper 9 and is detached from the clamping surface. In this state, the movable clamper 9 on the right side is displaced inward of the substrate beyond the stroke in the state where the substrate 10 is normally clamped. This displacement is detected by the sensor 23 detecting the dog member 22, whereby the side end of the substrate 10 is moved to the clamper 9.
A state of being detached from the clamp surface is detected. That is,
The dog member 22 that moves together with the sensor 23 and the clamper 9 that are fixedly arranged serves as a clamp disengagement detecting means for detecting the above-mentioned clamp disengagement state. A mask plate 11 is disposed above the substrate positioning portion 1, and the mask plate 11 is provided with a large number of pattern holes 11a. The substrate 10 is aligned with the mask plate 11 by the substrate positioning unit 1 and comes into contact with the mask plate 11 from below.
A squeegee unit 12 is disposed on the mask plate 11. The squeegee unit 12 includes a cylinder 13
Two squeegees 14 that are driven up and down are provided, and can be reciprocated in the horizontal direction (Y direction) by a moving means (not shown). In a state where the substrate 10 is in contact with the lower surface of the mask plate 11, cream solder is supplied onto the mask plate 11, and the squeegee 14 is brought into contact with the surface of the mask plate 11 and is slid to contact the substrate 10. The cream solder is printed on the surface of the film through the pattern holes 11a. This screen printing apparatus is constructed as described above, and the operation will be described below with reference to FIGS. Before squeezing by the squeegee unit 12 is started, a substrate mounting operation for positioning the substrate 10 described below and bringing the upper surface of the substrate 10 into close contact with the lower surface of the mask plate 11 is performed. First, transport rail 8
The substrate 10 carried into the substrate positioning unit 1 by Z
The lower surface is held by a lower receiving portion provided on the upper portion of the shaft table 4. Then, after the horizontal position of the substrate 10 is adjusted by the X-axis table 3 and the Y-axis table 2 of the substrate positioning unit, the Z-axis table 4 is raised as shown in FIG. 11 is brought into contact with the lower surface. In this state, the cylinder 21 is driven to clamp the side end portion of the substrate 10 by the clamper 9 and clamp it. Thereby, the horizontal position of the board | substrate 10 is fixed in the squeegeeing by the squeegee unit 12. At the time of the clamping operation for moving the clamper 9 or during squeezing, there may be a case where the substrate 10 is detached from the clamping surface of the clamper 9 as shown in FIG. In this case, the sensor 23 detects the dog member 22 as described above, thereby detecting that the clamp is disengaged and informing that. Immediately after that, the operation of the screen printing apparatus is stopped, and the operator takes necessary measures. As a result, normal screen printing operation can be performed without causing problems such as substrate cracking due to the next substrate being carried in with the substrate 10 out of the clamped state kept in close contact with the lower surface of the mask plate 11. Can be done. According to the present invention, the clamping means for holding the side end portion of the substrate sandwiched from both sides by the clamping surface in the substrate positioning portion, and the state where the side end portion of the substrate is detached from the clamping surface are provided. Since the clamp disengagement detecting means for detecting is provided, it is possible to reliably detect the disengagement of the substrate and prevent an operation abnormality caused by continuing the printing operation while the substrate is out of the clamped state.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side view of a screen printing apparatus according to an embodiment of the present invention. FIG. 2 is an explanatory view of a clamp driving mechanism of the screen printing apparatus according to an embodiment of the present invention. FIG. 4 is a side view of a screen printing apparatus according to an embodiment of the present invention. DESCRIPTION OF SYMBOLS 1 Substrate positioning portion 8 Transport rail 9 Clamper 10 Substrate 20 Clamp drive mechanism 21 Cylinder 22 Dog member 23 Sensor

Continued front page    (72) Inventor Takahiro Fukagawa             1006 Kadoma, Kadoma, Osaka Prefecture Matsushita Electric             Within Sangyo Co., Ltd. (72) Inventor Takaaki Sakagami             1006 Kadoma, Kadoma, Osaka Prefecture Matsushita Electric             Within Sangyo Co., Ltd. F term (reference) 2C035 AA06 FA32 FB24 FC07 FD01                 5E319 AA03 AB05 AC01 BB05 CD29                       GG15                 5E343 AA02 BB72 DD03 FF02 GG11                       GG18

Claims (1)

What is claimed is: 1. A substrate having a pattern hole formed thereon is brought into contact with the substrate, a paste is supplied onto the mask plate, and a squeegee is slid to allow the substrate to pass through the pattern hole. A screen printing apparatus for printing a paste on a substrate, a substrate transport means for transporting the substrate, a substrate positioning unit for holding and positioning the transported substrate, and a clamping surface at a side edge of the substrate in the substrate positioning unit A screen printing apparatus comprising: clamping means for sandwiching and holding the sheet from both sides; and clamping disengagement detecting means for detecting a state in which the side end portion of the substrate is detached from the clamping surface.