JP2004338139A - Screen printer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a screen printer which can prevent productivity from decreasing in a change in an interval between regulating members, while suppressing an influence of inertia in movement of a squeegee and responding to the request of a reduction in costs, though the interval between the regulating members can be changed by a simple constitution. <P>SOLUTION: This screen printer is equipped with the squeegee 9 which comprises a slender squeegee body 9a, a squeegee holder 9b for holding the squeegee body 9a, and the paired regulating members 9c for regulating a flow of solder paste to the longitudinal outside of the squeegee body 9a; and each of the regulating members 9c is constituted in such a manner as to be displaceable in the longitudinal direction of the squeegee body 9a with respect to the squeegee body 9a, and constituted in such a manner as to be held in an arbitrary position on the squeegee body 9a or the squeegee holder 9b by a magnetic force. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a screen printer for applying a solder paste to a substrate.
[0002]
[Prior art]
Conventionally, a mask sheet for screen printing is superimposed on a substrate set on a stage, and a solder paste supplied on the mask sheet is spread and spread by a squeegee, so that a predetermined portion of the substrate is formed through an opening formed in the mask sheet. Screen printing machines that apply a solder paste (hereinafter abbreviated as paste) to positions are generally known.
[0003]
In this type of printing press, a paste storage portion having a wedge-shaped cross section is formed by a mask sheet and a squeegee sliding on the mask sheet, and the paste is applied to the substrate while the paste is stored in the storage portion as the squeegee moves. However, at this time, if the paste in the pool portion escapes to both outer sides in the width direction of the squeegee along with the movement of the squeegee (hereinafter referred to as lateral leakage), the rolling height, that is, the paste height stored in the pool portion changes greatly in the moving direction. Adversely affects the finish and wastes the paste. Therefore, conventionally, paste regulating plates are provided on both sides in the width direction of the squeegee, thereby preventing lateral leakage of the paste during movement of the squeegee.
[0004]
By the way, since the size and location of the substrate on which the paste is to be applied vary depending on the type of the substrate, it is convenient if the spacing between the regulation plates can be changed accordingly. As such a device, there is known a device in which a regulating plate is supported so as to be movable in the width direction, and the regulating plate is driven by a driving mechanism using a motor as a driving source (for example, see Patent Document 1). Further, there is a device in which a regulating plate is bolted to a rail and the bolt can be loosened to be movable in the longitudinal direction of the rail (for example, see Patent Document 2).
[0005]
[Patent Document 1]
JP-A-5-293947 [Patent Document 2]
JP-A-6-42168 [0006]
[Problems to be solved by the invention]
However, in the device disclosed in Patent Literature 1, since the drive mechanism of the regulating plate needs to be constantly moved together with the squeegee, the weight of the movable part including the vigorous squeegee increases, and as a result, the squeegee is easily affected by inertia. In addition, there is an adverse effect on quick work and finish accuracy. In addition, there is a disadvantage that the cost is increased. In the case of the apparatus disclosed in Patent Document 2, such a problem does not exist, but each time the distance between the regulating plates is changed, four positions (two squeegees for forward printing and return printing, respectively, near both ends in the longitudinal direction) It is necessary to loosen and retighten the bolts one by one.) For this reason, it is inevitable that the operation takes time and the productivity decreases when the interval between the regulating plates is changed.
[0007]
The present invention has been made in view of the above problems, and has a squeegee provided with a regulating plate (regulating member) to prevent lateral leakage of paste, and can change the interval between the regulating members with a simple configuration. However, it is an object of the present invention to provide a screen printing machine capable of suppressing the influence of inertia when moving a squeegee, responding to a demand for cost reduction, and preventing a decrease in productivity when changing the interval between regulating members.
[0008]
[Means for Solving the Problems]
In order to solve the above problem, the invention according to claim 1 includes an elongated squeegee main body, a squeegee holder for holding the squeegee main body, and a pair of squeegee main bodies that regulate the flow of the solder paste outward on both longitudinal sides of the squeegee main body. In a screen printing machine provided with a squeegee having a regulating member, each of the regulating members is configured to be capable of changing its position in the longitudinal direction with respect to the squeegee body, and the squeegee body or the squeegee holder is provided with an arbitrary magnetic force. It is configured to be held in position.
[0009]
In this way, if the restricting member is held on the squeegee main body or the like at an arbitrary position in the longitudinal direction of the squeegee by magnetic force, the interval between the restricting members can be changed with a simple configuration. Therefore, the distance between the regulating members can be changed without adverse effects such as an increase in weight and cost of the movable portion including the squeegee. Also, the bolts are loosened or tightened by setting the magnitude of the magnetic force to such a level that the operator can easily attach and remove it (however, the strength of the regulating member does not shift in the longitudinal direction due to the flow pressure of the paste). The operation of changing the distance between the regulating members can be easily performed without the operation of performing the above operation.
[0010]
Specifically, in the screen printing machine according to claim 1, the squeegee main body is a magnetic material, and each of the regulating members is held by directly or indirectly abutting a magnet provided therein to the squeegee main body. It is preferred to be constituted so that (claim 2).
[0011]
According to this configuration, since the squeegee itself is a magnetic material attracted by the magnet, the regulation member can be easily held by merely providing the magnet to the regulation member.
[0012]
In addition, a magnetic intermediate plate provided integrally with the squeegee main body is provided, and each of the regulating members is held by directly or indirectly abutting a magnet provided therein with the intermediate plate. With such a configuration, even when the squeegee is a non-magnetic material such as urethane, the regulating member can be held via the intermediate plate, and the degree of freedom in selecting the squeegee material can be increased.
[0013]
It is preferable that the screen printing machine according to any one of claims 1 to 3 be configured to include a pressing unit that presses each of the regulating members toward the mask sheet (claim 4).
[0014]
According to this configuration, the restricting member and the mask sheet can be brought into close contact with each other by the pressing means, so that lateral leakage of the paste from the gap can be effectively prevented.
[0015]
Specifically, the pressing means is a spring plunger provided inside each of the restricting portions, and the spring plunger applies a pressing force to the squeegee body or the squeegee holder in a direction opposite to the mask sheet side. It is preferable to configure as (claim 5).
[0016]
According to this configuration, by using a spring plunger, which is a general mechanical element, a simple structure and inexpensive pressing means can be provided.
[0017]
The screen printing machine according to any one of claims 1 to 5, wherein a scale is provided in the vicinity of a holding position of each of the regulating portions, along a longitudinal direction of the squeegee main body, and the scale is formed from a substantially center origin. It is more preferable that both sides are attached at a scale of one half of the actual length (claim 6).
[0018]
According to this configuration, the operator can easily determine the holding position of the regulating member by the scale, and the workability is further improved. Moreover, since the scales are provided on both sides of the scale from the origin substantially in the center at a scale of one half of the actual length, if the regulating members on both sides are set at specific scale positions (for example, 100 mm), each scale is The restricting member is held at a position separated from the center origin by half its actual length (50 mm). That is, each regulating member is distributed at an equal distance from the origin, and the interval is a specific scale (100 mm). In this way, the operator can easily set the interval between the regulating members to the center in accordance with the width of the board having a certain width, so that the workability can be further improved.
[0019]
BEST MODE FOR CARRYING OUT THE INVENTION
A first embodiment of the present invention will be described with reference to the drawings.
[0020]
FIG. 1 shows an embodiment of a screen printing machine according to the present invention. The screen printing machine is provided with a printing press main body 2 having a base 1 and a substrate support unit 3 for supporting a printed circuit board W, and carries the substrate W onto and out of the substrate support unit 3. Conveyor 3A is placed and fixed.
[0021]
Although not shown in detail, the substrate support unit 3 has an elevating rotary table 4 installed on the base 1, and is provided in the elevating rotary table 4 or on the base 1. By the moving mechanism, the X-axis direction of the printing press main body 2 (the direction of loading / unloading of the substrate W by the conveyor 3A, that is, the direction orthogonal to the plane of FIG. 1), the Y-axis direction (the left-right direction in FIG. 1), and the Z-axis direction The support position of the substrate W can be moved in the vertical direction and in the θ direction (rotational direction around the Z axis).
[0022]
The printing press main body 2 is installed so as to connect the support frames 2a arranged at the four corners of the base 1 with the upper portions of the support frames 2a at the four corners, and is open at the front (left side in FIG. 1). And a U-shaped upper frame 2b.
[0023]
Above the substrate support unit 3, there is arranged a mask sheet 7 whose entire circumference is held by a frame member 8 fixed to the upper frame 2b, and above this mask sheet 7, a squeegee mechanism 5 is arranged. Have been.
[0024]
The squeegee mechanism 5 includes a rail member 5a provided on a pair of front and rear upper frames 2b in a direction perpendicular to the paper surface of FIG. 1, and both ends mounted on each rail member 5a, and a Y-axis direction (FIG. 1). A spar member 5b movable in the left-right direction by a single-axis robot (not shown), a pair of squeegees 9 and 9 elongated in the X-axis direction for extending the solder paste on the mask sheet 7, and the spar member 5b And lifting means 10 for driving the squeegees 9, 9 up and down.
[0025]
Each of the squeegees 9, 9 includes a squeegee body 9a, a squeegee holder 9b for holding the squeegee, and a pair of regulating members 9c for preventing the paste from leaking laterally, as will be described in detail later. The elevating unit 10 is detachably attached to a pair of mounting holders 12 of the elevating means 10 provided at a predetermined interval in the axial direction. Although not particularly shown, a tip of a piston rod of a pneumatic cylinder device of the lifting / lowering means 10 is connected to an upper central portion of the mounting holder 12, and rods are erected on both upper ends of the mounting holder 12, and these are connected to the lifting / lowering means. It is slidably supported by ten guide bushes.
[0026]
Further, a cleaning unit 16 is provided on the base 1 beside the substrate support unit 3. The cleaning unit 16 is provided so as to be movable between a central cleaning position corresponding to a printing position by the squeegee mechanism 5 and the like and a standby position (a position shown by a solid line in FIG. 1) provided on a side portion of the base 1. And it is configured to be connectable to the substrate support unit 3. That is, it is configured to move between these positions together with the substrate support unit 3 by being connected to the substrate support unit 3.
[0027]
The printing operation by the screen printing machine will be schematically described as follows.
[0028]
First, the substrate support unit 3 is moved to a predetermined substrate receiving position by the operation of the elevating rotary table 4, and the substrate W is transferred onto the substrate support unit 3 by being transported along the conveyor 3A. Will be retained. Next, after the substrate support unit 3 moves below the mask sheet 7 and the substrate W is positioned in the X, Y, and θ directions with respect to the mask sheet 7, the substrate support unit 3 is moved upward, whereby the substrate W is masked. The sheet is set at a predetermined printing position in contact with the back surface of the sheet 7.
[0029]
When the substrate W is set at the printing position, the squeegee 9 is set at a predetermined height at the work start position, that is, at a position where the tip (lower end) of the squeegee abuts on the mask sheet 7, and then the squeegee mechanism 5 is driven. As a result, the squeegee 9 moves in the Y-axis direction. As a result, the squeegee 9 slides along the surface of the mask sheet 7, and the paste on the mask sheet 7 is spread and spread and applied to the substrate W through the opening formed in the mask sheet 7. .
[0030]
When printing is completed, after the squeegee 9 is reset to the rising end position, the substrate support unit 3 is lowered, further moved to the substrate sending-out position, and the substrate W is transported along the conveyor 3A. As a result, the substrate W is sent out from the substrate support unit 3 to the next step.
[0031]
During the printing operation of the substrate W, the cleaning unit 16 and the substrate support unit 3 are connected at a certain timing, and the cleaning unit 16 is pulled out from the standby position to the cleaning position, thereby cleaning the mask sheet 7. Will be performed.
[0032]
FIG. 2 shows a specific configuration of the squeegee 9 in the screen printing machine, and FIG. 3 is a sectional view taken along the line AA in FIG. Although the printing press is provided with a pair of squeegees 9, 9, the configuration of each squeegee 9 is basically the same except that the orientation is different. Will be described only.
[0033]
As shown in these figures, the squeegee 9 comprises a squeegee body 9a, a squeegee holder 9b for holding the squeegee, and a pair of regulating members 9c for preventing lateral leakage of the paste. To be removably attached to a mounting holder 12 provided at the same position.
[0034]
The squeegee main body 9a is a thin plate-shaped member (metal squeegee) made of a magnetic material such as SK material or magnetic stainless steel, and is formed to be elongated in the X-axis direction.
[0035]
As shown in FIG. 3, the squeegee holder 9b includes a holder main body 20 having a lower surface on which a mating surface 20a for the squeegee main body 9a is provided, a fixing plate 22 for fixing the squeegee main body 9a, and a rail plate having a J-shaped cross section. 23. The squeegee holder 9b is made of, for example, iron or aluminum die cast, and has an elongated shape in the X-axis direction corresponding to the squeegee 9. Then, as shown in the figure, the squeegee main body 9a is superimposed on the mating surface 20a, and the fixed plate 22 and the rail plate 23 are further superimposed on the squeegee main body 9a. The squeegee body 9a is configured to be held between the holder body 20, the fixed plate 22, and the rail plate 23 by inserting the bolt 21 from above and screwing the bolt 21 into the screw hole 22a of the fixed plate 22. I have.
[0036]
A pair of detachable bolts 24 for attaching the squeegee 9 to the squeegee mechanism 5 are provided at predetermined intervals in the longitudinal direction (X-axis direction) above the squeegee holder 9b. These detachable bolts 24 are screwed into screw holes formed in the upper part of the holder body 20, respectively. That is, the detachment bolt 24 is inserted into a notch (not shown) of the attachment holder 12 from the horizontal direction, and the attachment holder 12 is inserted between the head of the detachment bolt 24 and the holder main body 20 as shown by a dashed line in FIG. The squeegee 9 is attached and fixed to the attachment holder 12 via the holder main body 20 by fastening the attachment / detachment bolt 24 in the interposed state.
[0037]
Each regulating member 9c includes a regulating block 26 which is a block body such as polyacetal (trade name: Duracon), and a magnet 27 and a spring plunger 28 built in the regulating block 26.
[0038]
The restricting block 26 is formed so that the bottom surface is in contact with the mask sheet 7 and one side surface in the Y-axis direction is in contact with the squeegee main body 9a. A regulating wall 26b is formed near the bottom surface of the regulating block 26. The restricting wall 26b is an upright wall parallel to the Y-axis having a widened portion in front of the squeegee 9 in the Y-axis moving direction. The regulating wall 26b has a bottom surface in contact with the mask sheet 7 without any gap, and a rear end surface in the moving direction is in contact with the squeegee body 9a. Touching without gap. That is, a corner without a gap is formed by the regulating wall 26b and the mask sheet 7, and a corner without a gap with the squeegee body 9a is further formed at the rear end of the corner. These corners and corners are the ends of the paste pool, and the paste is configured not to leak out from these corners and corners to the outside.
[0039]
A concave portion 26c having a circular cross section and an axis thereof being perpendicular to the plate surface of the squeegee main body 9a is provided on a surface of the restricting block main body 26a constituting the restricting block 26 in contact with the squeegee main body 9a. A magnet 27 having a columnar shape and having a height substantially equal to the depth of the concave portion 26c is fitted into and fixed to the concave portion 26c. That is, the magnet 27 is provided on the regulating member 9c such that the upper surface thereof is in contact with the squeegee main body 9a. The restriction block 26 is held by the squeegee main body 9a by a magnetic force acting between the magnet 27 and the magnetic squeegee main body 9a.
[0040]
The regulating member 9c is provided with a pair of spring plungers 28 (pressing means) at positions on both sides of the magnet 27 in the X-axis direction. (FIG. 3 shows one of them). The spring plunger 28 is embedded in the regulating block main body 26 a so that its axis is parallel to the plate surface of the squeegee main body 9 a, and the tip of the plunger abuts on the bottom surface of the rail portion 23 a of the rail plate 23. . Accordingly, the spring plunger 28 applies a pressing force to the squeegee holder 9b in a direction opposite to the mask sheet 7 side by an internal spring biasing force. Then, the regulating block 26 is pressed against the mask sheet 7 by the reaction, so that the regulating wall 26b comes into close contact with the mask sheet 7.
[0041]
A hanging portion 26d having an inverted J-shaped cross-sectional shape, which is engaged with the rail portion 23a of the rail plate 23, is formed at an upper portion of the restriction block main body 26a. Therefore, even when the regulating block 26 is held by the squeegee main body 9a, the regulating block 26 can slide in the X-axis direction along the rail plate 23 by the force opposing the magnetic force of the magnet 27. Further, if the magnet 27 is slightly lifted from the squeegee main body 9a in a state where the rail portion 23a and the hanging portion 26d are engaged, it is possible to slide with a lighter force.
[0042]
By the way, on the fixing plate 22, a regulation portion position scale 22b for indicating the position of the regulation member 9c in the X-axis direction is displayed (see FIG. 2). More specifically, a center mark 22c is displayed at the center in the X-axis direction, and scales are provided on both sides of the center mark 22c at the scale of 1/2 of the actual length. For example, a numerical value or a mark indicating 100 mm is attached to each side of the scale center 22c, which is 50 mm in actual length and separated from each other by 50 mm. Therefore, if the regulating member 9c is set so that the regulating wall 26b of each regulating block 26 matches the position indicating this 100 mm, the interval between the regulating walls 26b on both sides becomes 100 mm in actual length, and the middle point is the scale. It coincides with the center 22c (becomes a center distribution).
[0043]
According to the screen printing machine described above, the regulating member 9c is provided on the squeegee 9 as described above, and the regulating wall 26b of the regulating member 9c and the mask sheet 7 are configured to be in close contact with each other. During operation, it is possible to effectively prevent lateral leakage of the paste, that is, a phenomenon in which the paste escapes to the outside in the width direction of the squeegee body 9a during operation. Therefore, it is possible to effectively avoid adverse effects on the finish due to fluctuations in the rolling height and wasteful consumption of the paste.
[0044]
Moreover, since the regulating wall 26b is brought into close contact with the mask sheet 7 by the spring plunger 28, the leakage of the paste from the gap between the regulating wall 26b and the mask sheet 7 is highly prevented, and a remarkable lateral leakage preventing effect is obtained. Play.
[0045]
When changing the distance between the restriction walls 26b, the suspension of the restriction block 26 is performed in a state where the squeegee main body 9a and the magnet 27 are in contact with each other or in a state where the magnet 27 is slightly lifted from the squeegee main body 9a. The gap can be easily changed simply by sliding the hanging portion 26d in the X-axis direction along the rail portion 23a of the rail plate 23. Therefore, unlike a conventional screen printing machine in which a motor-driven regulating member is mounted on a squeegee, the squeegee is easily affected by inertia when the squeegee is actuated, which hinders quick work or increases costs. Will not be involved. Further, since the work of loosening or tightening the bolt as in the conventional device for fixing the regulating member with the bolt is not required, the work can be performed quickly and the productivity can be improved.
[0046]
Further, the regulating member position scale 22b allows the regulating member 9c to be easily and promptly set to the target interval by allocating to the center, thereby further improving the working efficiency.
[0047]
Next, a second embodiment of the present invention will be described with reference to FIG.
[0048]
In the second embodiment, the same parts as those in the first embodiment are denoted by the same reference numerals, and the description thereof will not be repeated. The squeegee 9 has the same basic configuration as that of the first embodiment. However, the material of the squeegee body 9a is a non-magnetic urethane or non-magnetic stainless steel. This is different from the first embodiment in that a magnetic intermediate plate 29 is provided between them. More specifically, the intermediate plate 29 is a thin plate made of SK material, magnetic stainless steel, or the like, and is provided along the longitudinal direction of the squeegee main body 9a. The intermediate plate 29 may be a separate member sandwiched between the squeegee main body 9a and the rail plate 23, or may be a member fixed to one side. The intermediate plate 29 is configured to contact at least the magnet 27. Therefore, the regulating member 9c is held by the squeegee main body 9a via the intermediate plate 29 by a magnetic force acting between the magnet 27 provided therein and the magnetic intermediate plate 29.
[0049]
According to the configuration of the second embodiment, even if the squeegee main body 9a is a non-magnetic material, the regulating member 9c can be held by the magnetic force, so that the same operation and effect as the first embodiment can be obtained. Can be. Although the squeegee body 9a may be made of a magnetic material, the squeegee body 9a may be configured as in the second embodiment. It is more preferable to perform this operation from the viewpoint of reducing the number of parts and cost.
[0050]
The screen printer described in the first and second embodiments is a part of the embodiment of the screen printer according to the present invention, and has a specific configuration of the squeegee and a specific configuration of the screen printer. The present invention is not limited to the above embodiment, and can be appropriately changed without departing from the gist of the present invention.
[0051]
For example, in the first embodiment, the upper surface of the magnet 27 does not need to be exposed so as to directly contact the squeegee main body 9a or the intermediate plate 29. Inclusions may be provided.
[0052]
One or three or more spring plungers 28 may be provided for each regulating member 9c. The spring plunger 28 is an embodiment of the pressing means, but the pressing means is not limited to the spring plunger 28 as long as it presses the regulating member 9c toward the mask sheet 7 side. For example, another mechanism (such as a ball plunger) mainly including a coil spring, a mechanism using another elastic member such as rubber, or a mechanism using fluid pressure may be used.
[0053]
【The invention's effect】
As described above, the present invention relates to a screen printer including a squeegee having a regulating member that regulates the flow of the solder paste, wherein each of the regulating members is positioned in a longitudinal direction with respect to the squeegee body. In addition to being configured to be changeable, the squeegee body or the squeegee holder is configured to be held at an arbitrary position by a magnetic force. It is possible to suppress the influence of inertia and meet the demand for cost reduction, while preventing a decrease in productivity at the time of changing the regulating member interval.
[Brief description of the drawings]
FIG. 1 is an overall configuration diagram showing a screen printing machine according to the present invention.
FIG. 2 is a front view showing a configuration of a squeegee (first embodiment).
FIG. 3 is a cross-sectional view of the squeegee taken along line AA in FIG.
FIG. 4 is a cross-sectional view of a portion corresponding to FIG. 3 in the second embodiment.
[Explanation of symbols]
9 squeegee 9a squeegee body 9b squeegee holder 9c regulating member 26 regulating block 26b regulating wall 27 magnet 28 spring plunger (pressing means)
29 Intermediate plate

Claims (6)

An elongated squeegee body, a squeegee holder that holds the squeegee body, and a screen printer including a squeegee having a pair of regulating members that regulate the flow of the solder paste to the outside on both sides in the longitudinal direction of the squeegee body,
Each of the restricting members is configured to be changeable in its longitudinal direction with respect to the squeegee main body, and is held at an arbitrary position by the magnetic force on the squeegee main body or the squeegee holder. Screen printing machine. The screen printing machine according to claim 1,
A screen printing machine, wherein the squeegee main body is a magnetic material, and each of the regulating members is held by directly or indirectly abutting a magnet provided therein to the squeegee main body. The screen printing machine according to claim 1,
A magnetic intermediate plate provided integrally with the squeegee body is provided, and each of the regulating members is held by directly or indirectly abutting a magnet provided therein with the intermediate plate. Screen printing machine. The screen printing machine according to any one of claims 1 to 3,
A screen printing machine comprising a pressing means for pressing each of the restricting members toward the mask sheet. The screen printing machine according to claim 4,
The pressing means is a spring plunger provided inside each of the restricting portions, and the spring plunger is configured to apply a pressing force to the squeegee body or the squeegee holder in a direction opposite to the mask sheet side. A screen printing machine. The screen printer according to any one of claims 1 to 5,
A scale is provided in the vicinity of the holding position of each of the restricting portions along a longitudinal direction of the squeegee main body. The scale is provided on both sides of the scale at a half scale of the actual length from a substantially central origin. A screen printing machine.

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