JP3346803B2 - Printed circuit board support method and apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for supporting a flexible printed circuit board from the back side and an apparatus suitable for carrying out the method. The present invention relates to a method and an apparatus for supporting a printed circuit board having irregularities on the back surface.

[0002]

2. Description of the Related Art Most printed circuit boards are formed by forming a circuit pattern made of a conductive material on a relatively thin flat plate made of an electrically insulating material such as a synthetic resin, and have flexibility. Therefore, when mounting electronic components on such a printed circuit board, or when applying an adhesive or creamy solder for mounting electronic components, the printed circuit board must be supported at a considerable number of points on the back side. It cannot support while maintaining a desired shape such as a flat surface.

When the back surface of the printed circuit board is a flat surface having no unevenness, there is no problem since the printed circuit board can be supported by a support plate having a flat support surface. However, electronic components are already mounted on the back side. When the back surface has irregularities, it becomes difficult to support the back surface. In such a case, conventionally, the printed circuit board is supported by a large number of protrusions and support pins. For example, in the case where the back surface is uneven because an electronic component is already mounted, a portion where the electronic component is not mounted is selected and supported by a projection or a support pin. However, different types of printed circuit boards have different positions where electronic components are mounted.Therefore, prepare a dedicated support having a large number of protrusions formed in accordance with each printed circuit board, and prepare the type of printed circuit board. It is necessary to replace the support tool each time is changed or to correct the position of the support pin according to each printed circuit board.

[0004] When a dedicated support is prepared for each printed circuit board, it takes a certain period of time to manufacture the support, and the equipment cost increases. Also, when correcting the position of the support pins according to each printed circuit board,
A great deal of time is required for the setup change, and when the type of the printed circuit board changes frequently, it cannot be dealt with at all.

[0005]

SUMMARY OF THE INVENTION Under the above circumstances, the present invention provides a printed circuit board supporting method and apparatus which can support various kinds of printed circuit boards and can perform setup change in a very short time. This was done as an issue.

[0006]

A feature of the printed circuit board supporting method according to the present invention is that
Is deformed along the shape of the supported surface if pressed
And retains its shape even after the pressing force is released
Use flexible materials to support flexible printed circuit boards
That a method, the supported surface of the printed circuit board, a shape that the surface of the semi-fluid material against the surface of the semi-fluid substance complementary to the shape of the <br/> supported surface molding And a step of supporting the supported surface of the printed circuit board on the surface of the semi-fluid substance formed by the molding step. Causing the semi-fluid substance to undergo plastic deformation
Film that can follow the complementary shape
And cover the surface of the semi-fluid material through the film.
By supporting the support surface, semi-fluid substances can be
Method to support the printed circuit board without direct contact
You. Further, the feature of the printed circuit board supporting device according to the present invention is that if pressed against the supported surface of the printed circuit board, it is deformed along the shape of the supported surface, and the pressing force is released.
A semi-fluid substance that retains its shape afterwards, a support member that can be regarded as substantially rigid and supports the semi-fluid substance, a pressing member that faces the semi-fluid substance supported by the support member, approximate the pressing member and the support member to each other, seen including a moving device for separating, pressing member, to the mobile device
The holding member and the support member are brought close to each other,
When the quality is pressed against the supported surface of the printed circuit board.
The printed circuit board from the side opposite to the semi-fluid material and
It is to suppress only . The support member has a container which has an opening facing the holding member and stores a semi-fluid substance therein, and the semi-fluid substance in the container is added to the container. If a pressurizing device for pressing is provided, a more excellent printed circuit board supporting device can be obtained. The above semi-fluidity
Transforms a material into a semi-fluid material without plastic deformation
To be covered by a film that can conform to the surface shape of the quality
The surface of the semi-fluid material makes direct contact with the printed circuit board
A supporting device is obtained without having to do this.

[0007]

The semi-fluid substance deforms according to the shape of the object having the unevenness when the object is pressed, and the shape of the surface becomes a shape complementary to the surface of the object, even after the pressing force is released. Maintain shape. Therefore, in the method for supporting a printed board according to the present invention, the printed board having irregularities on the back surface is pressed against the semi-fluid substance to form a supporting surface complementary to the back surface which is the supported surface of the printed board. It was done. Of course, the support surface thus formed is deformed when a large force is applied,
Mounting of electronic components on printed circuit boards, application of adhesive and creamy solder (these are collectively referred to as processing of printed circuit boards)
Since the applied force is usually not so large, the support surface sufficiently withstands the force and maintains a predetermined shape. Further, when deformation occurs, it may be re-formed. Since molding is easy, it can even be performed each time processing of one printed circuit board is completed. Semi-fluid
Quality is in the above complementary relationship without plastic deformation
Print base in a form covered by a film that can conform to the shape
According to the board support method, the supported surface of the printed circuit board is semi-fluid
Formed on the supported surface of the printed circuit board
When the projected protrusion is forced into the semi-fluid substance
The film deforms with the surface of the semi-fluid material,
Deformation of the surface into a shape complementary to the supported surface
Allow the surface of the semi-fluid material to
Indirectly supporting the supported surface through a film
Become. Since the film does not undergo plastic deformation, the supported surface
It deforms according to its shape, and the semi-fluid substance passes through the film.
Support various types of printed circuit boards with different supported surfaces.
You can have.

Further, the printed circuit board supporting device according to the present invention includes the holding member and the moving device in addition to the semi-fluid substance and the supporting member, so that the semi-fluid substance supported by the supporting member can be used. With the holding member separated,
The printed circuit board is placed between the two with the back surface facing the semi-fluid material, and if the supporting member and the pressing member are brought close to each other by the moving device, the back surface of the printed circuit board is moved to the front surface of the semi-fluid material by the pressing member. And the surface of the semi-fluid material is formed into a shape complementary to the back surface of the printed circuit board. After that, even if the supporting member and the pressing member are separated by the moving device, the surface of the semi-fluid substance maintains the formed shape and continues to support the printed circuit board from the back side.

The distance between the holding member and the supporting member is sufficiently large, and an electronic component mounting head or an application head such as an adhesive is applied between the holding member and the printed circuit board supported by the semi-fluid material (these are used as substrate processing heads). And a device equipped with these processing heads is generally referred to as a substrate processing device), the printed circuit board can be processed as it is. When the separation distance is small, the support member and the semi-fluid substance may be moved to a position off the holding member, or the holding member may be moved to a position off the holding member.

The holding member and the moving device can be provided in the substrate processing apparatus, or can be provided separately from the substrate processing apparatus. In the latter case, the processing is performed by moving the printed board supported by the support member and the semi-fluid material to the substrate processing apparatus. In this case, a plurality of support members and semi-fluid substances are provided for one substrate processing apparatus,
It is also possible to use these sets of support members and semi-fluid material cyclically to perform the function of one component of the printed circuit board transport device.

The supporting member has an opening facing the holding member, and is a container for storing the semi-fluid substance therein, and a pressurizing device for pressurizing the internal semi-fluid substance is provided in the container. According to the printed circuit board supporting device of the aspect, the semi-fluid material can be more accurately made to conform to the shape of the printed circuit board back surface as compared with the case where the back surface of the printed circuit board is simply pressed against the semi-fluid material, The support surface can be formed at an accurate position. The protrusions (for example, already mounted electronic components) formed on the back surface of the printed circuit board rush into the semi-fluid substance when the printed circuit board and the semi-fluid substance are pressed, and the semi-fluid of that part The surface of the other part of the semi-fluid material is correspondingly higher in order to exclude the volatile material. Since the sum of the volumes of the protrusions formed on the back surface of the printed board usually changes when the type of the printed board changes, the height of the support surface after the molding of the semi-fluid substance is determined by the type of the printed board. In the case where the backside of the printed circuit board is simply pressed against the semi-fluid substance, it must be allowed, but if a pressurizing device is provided in the container, Since the amount of the semifluid substance can be adjusted, the change in the total volume of the protrusions can be absorbed by the pressurizing device, and the height of the support surface can be kept constant. In addition, semi-fluid
The quality of semi-fluid material after deformation without plastic deformation
Of a form covered by a film that can conform to the shape of the surface of the quality
According to the printed circuit board support device, the surface of the semi-fluid substance
Printed circuit board supporting method of embodiment covered with film
As in the case of semi-fluid, many types of
The lint substrate can be supported indirectly.

[0012]

As is apparent from the above description, the method for supporting a printed circuit board according to the present invention forms a support surface corresponding to the irregularities on the back surface of the printed circuit board on the surface of the semi-fluid substance and prints the support surface. Since the substrate is supported and the supporting surface is easily formed, various printed boards can be supported with little change in setup. Further, according to the printed board supporting device of the present invention, the above supporting method can be satisfactorily carried out. In particular, according to the printed board supporting device having the container and the pressurizing device, various printed boards are provided. Can be accurately defined. In addition, the semi-fluid substance is
Method for supporting printed circuit board in covered mode and printing
According to the substrate supporting device, the printed circuit board is supported on its supporting surface.
Can be supported without fear of soiling.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described with reference to the drawings, taking as an example the case where the present invention is applied to the support of a printed circuit board in a screen printing machine for applying creamy solder (hereinafter abbreviated as solder) to a wiring pattern of the printed circuit board. This will be described in detail. The screen printing machine itself has been already known in Japanese Patent Publication No. Hei 2-13475 and the like except for the printed circuit board supporting device, and the known parts will be briefly described.

As shown in FIGS. 1 and 2, the screen printing machine of the present embodiment is movable on a substrate conveyor 12, a substrate holding device 14, and a bed 10 provided on a fixed bed 10. The apparatus includes a substrate positioning and supporting device 18, a screen positioning and supporting device 20, and a squeegee device 22 provided on the table 16.

The board conveyor 12 is made up of ropes 28 wound around a fixed rail 24 and a movable rail 26 endlessly, and the ropes 28 are moved so that the printed circuit board 30 is moved in the X-axis direction (in the horizontal direction in FIG. 1). Transport to The width of the board conveyor 12 is adjusted according to the dimensions of the printed circuit board 30 by moving the movable rail 26 with the rail feed screw 34, the nut 36, the sprocket 38, the chain 40, and the like.

A screen receiver 44 is fixed to the fixed rail 24 by a support member 42, and the movable rail 26
, A screen receiver 48 is fixed by a support member 46. These support members 42 and 46 are also provided with pressing plate guides 50 and 52, respectively, so as to guide the substrate pressing plate 54 of the substrate pressing device 14 so as to be movable only in a direction parallel to the transport direction of the printed circuit board 30. Have been. The board holding plate 54 is engaged with an engaging member provided on a chain (not shown), and is moved in a direction parallel to the transport direction of the printed board 30.

The substrate positioning and supporting device 18 includes a movable table 16
It is provided so that the height can be adjusted. The support plate 60 of the substrate positioning and supporting device 18 is connected to a pair of two cam followers 62 fixed to the support plate 60 by a feed screw 68 via a connecting rod 66 connecting the cam rods 64. By being moved, the height can be changed. A substrate support 70 is provided on the support plate 60 so as to be able to move up and down. The substrate support 70 is supported by a support plate 60 on a guide rod 72 fixed via an attachment member 71.
The printed board 30 is moved to the four height positions by the multi-stage cylinder 74 to contact and separate the screen from the screen. Note that the four height positions of the substrate support 70 are determined by the proximity switch 76 provided on the mounting member 71 and the four detection objects 78 provided on the support plate 60.

As shown in the enlarged view of FIG. 3, the upward opening of the container 79 of the shallow box-shaped
It is closed at 0 and contains a semi-fluid substance 81 inside. The film 80 is formed by forming a large number of fine wrinkles crossing each other on a film made of silicone rubber imparted with conductivity by mixing an electrostatic antistatic agent, does not charge static electricity, and is rich in deformability. And it does not generate plastic deformation. The semi-fluid 81 is
RTV rubber also containing an antistatic agent (room
Temparecha vulcanizing rubber) with antistatic properties and thixotropic properties (the property that a gel changes into a fluid sol simply by stirring or shaking, and returns to a gel when left alone) It is excellent.

A pressurizing device 82 is provided at the bottom of the container 79. A cylinder tube 83 as a main body of the pressurizing device 82 is fixed to a bottom wall of the container 79, and a piston 84 is fitted in the cylinder tube 83 in an airtight and slidable manner. volumes of space
It is divided into a product adjustment chamber 85 and a pressure chamber 86. The volume adjusting chamber 85 is always in communication with the space in the container 79, and the amount of the semi-fluid substance 81 stored in the volume adjusting chamber 85 can be changed by adjusting the volume of the volume adjusting chamber 85. . On the other hand, pressurized air is supplied from a pressurized air supply device (not shown) to the pressurizing chamber 86, and pressurizes the semi-fluid substance 81 in the volume adjusting chamber 85 and the container 79 via the piston 84.

In this embodiment, the container 79 constitutes a support member for the semifluid substance 81, and the substrate holding plate 54 constitutes a holding member.
Constitute a moving device for moving the container 79 and the substrate holder 54 toward and away from each other.

The screen positioning support device 20 and the squeegee device 22 are provided on a frame 88 mounted on the movable base 16 so as to be rotatable around a horizontal axis 87. A part of the frame 88 constitutes a screen support base 89 of the screen positioning support device 20.
On the screen support 89, a screen 92 attached to a screen frame 90 is fixed. Screen 9
2 is a printed circuit board 30 as shown in FIGS.
A through hole 94 for applying solder to the wiring pattern provided in the wiring pattern is provided corresponding to the wiring pattern. The screen 92 is moved along the X axis by a positioning device (not shown).
The fixed cylinder 10 is positioned in both directions of the Y axis.
6 secures to the screen support 89.

The squeegee device 22 includes two squeegees 11.
0,112. These squeegees 110 and 11
2 is an X provided on the frame 88 so as to be movable in the X-axis direction.
It is mounted on a shaft slide 114 so as to be able to move up and down, and is moved up and down by elevating cylinders 116 and 118. Also,
The X-axis slide 114 can be moved in the X-axis direction by a feed screw 120, a guide rod 122, and an X-axis drive motor 123.
When the slide 114 is moved in the X-axis direction in a state in which 12 is selectively lowered to the application position by the lifting cylinders 116 and 118, solder is applied to the wiring pattern of the printed circuit board 30.

The movable table 16 is provided on the board conveyor 1.
When the width of the movable rail 2 is changed, the movable rail 26 is moved in the same direction by half the distance, and the substrate positioning support device 18 and the screen positioning support device 2 provided on the movable base 16 are provided.
0, the squeegee device 22 is located at the center in the width direction regardless of the width of the board conveyor 12. When the carriage lead screw 130 connected to the chain 40 by the sprockets 124 and 128 and the chain 126 is rotated by the handle 132, the carriage 1
2 is moved by the guide rod 134 in the left-right direction in FIG. 2, the rotation of the handle 132 is transmitted to the rail feed screw 34 at twice the speed, and the movable rail 26 is moved twice the distance of the movable base 16. They can be moved.

When the width of the printed board 30 changes, the board support 70 is also replaced with a board that fits the width of the next printed board 30. The substrate support 70 is detachably fixed to the mounting member 71 by a fixing means such as a bolt (not shown).

At the time of screen printing in the screen printer configured as described above, a screen 92 corresponding to the type of the printed board is fixed to the screen support 89, and the printed board 3 on which the electronic components C are mounted on the back side.
0 is conveyed and brought into contact with the screen 92 from below. Printed circuit board 3 conveyed by board conveyor 12
The movement of 0 is stopped by a stopper device (not shown) and stopped just above the substrate support 70. The substrate support 70 is at the lower end position when the printed circuit board is carried in, and the substrate holding plate 54 is located above the substrate support 70.

After the printed circuit board 30 is loaded, the substrate support 7
0 is raised and the printed circuit board 30 is
2 and pressed against the board holding plate 54. At this time, the positioning pins provided on the fixed rails 24 are fitted into the positioning holes of the printed board 30 to accurately position the printed board 30. The upper end of the container 79 has a film 80 and a printed circuit board 30.
The electronic component C already mounted on the back side of the printed circuit board 30 protrudes into the semi-fluid substance 81 until it comes into contact with the substrate pressing plate 54 via the. At this time, the film 80 allows the electronic component C to enter the semi-fluid substance 81 while preventing the semi-fluid substance 81 from directly contacting the electronic component C and the printed circuit board 30.

As described above, the electronic component C is made of the semi-fluid substance 8
1, a semi-fluid substance 81 having a volume equal to the sum of the volumes of the electronic components C is pushed out of the container 79, but is added to the pressurizing device 82 when the printed circuit board 30 is raised. Since the compressed air is not supplied and the piston 84 can retreat freely, the volume of the volume adjustment chamber 85 increases to accommodate the semi-fluid substance 81 pushed out of the container 79.

After the substrate support 70 is raised to the rising end, pressurized air is supplied to the pressurizing device 82, and the piston 8
4 is advanced and the semi-fluid substance 8 in the volume adjustment chamber 85
1 is pressurized. Since the semi-fluid substance 81 also has a fluid property, the pressure of the semi-fluid substance 81 in the volume adjustment chamber 85 is transmitted to the semi-fluid substance 81 in the container 79, and this is printed via the film 80. It is brought into close contact with the back surface of the substrate 30. The surface of the semifluid substance 81 is formed into a support surface having a shape that is substantially complementary to the back surface of the printed circuit board 30.

After the molding, the pressurizing chamber 86 of the pressurizing device 82 is communicated with the atmosphere to release the pressurization of the semi-fluid substance 81, and the substrate support 70 is lowered a small distance so that the substrate holding plate 54 Separated. Since the semi-fluid substance 81 has the property of maintaining its shape unless a certain amount of force is applied after molding, the film 8
Then, the printed circuit board 30 descends while supporting almost the entire surface of the printed circuit board 30 via the line 0. Next, after the board holding plate 54 is retracted from above the printed board 30,
0 is raised to the rising end position, and the printed circuit board 30 is brought into contact with the lower surface of the screen 92.

Next, of the squeegees 110 and 112,
One of the squeegees 110 is lowered to the screen 92.
And is moved in the X-axis direction, and solder is applied to the printed circuit board 30 through the through holes 94 formed in the screen 92. At this time, the squeegee 110
Thus, a force is applied to the support surface of the semi-fluid substance 81 via the screen 92, the printed board 30, and the film 80, but this force does not deform the support surface, and the solder printing is performed without any trouble.

When the solder application is completed, the squeegee 1
After 10 is raised, the substrate support 70 is lowered, and the printed circuit board 30 is separated from the screen 92. Thereby, the solder applied to the printed board 30 escapes from the through hole 94 and is printed on the printed board 30 in a predetermined pattern. The substrate support 70 is
Even after the printed board 30 is supported by the board conveyor 12, the printed board 30 is lowered and returns to the lower end position.

In this embodiment, the semi-fluid substance 81 is covered with the film 80 so that the semi-fluid substance 81 does not come into direct contact with the electronic component C or the printed circuit board 30 to stain them. The semi-fluid substance 81 is an electronic component C
The film 80 can be omitted when the electronic component C or the like does not have a risk of soiling the electronic component C or the like.

Further, the semi-fluid substance is the RTV of the above embodiment.
The material is not limited to rubber, and a material having excellent or positively enhanced thixotropic properties, such as silicone putty, clay for various uses, thermal compound, silica gel, grease, and high viscosity oil, can be used. It is desirable to mix the antistatic agent to provide conductivity. The same applies to the film, and fluorine-based rubber, urethane rubber, natural rubber, nylon, vinyl chloride and the like can be used. It is desirable that all of them have excellent antistatic properties, deformability, and non-plastic deformability or positively enhance them.

The pressurizing device is not limited to the pressurizing device 82 that pressurizes using pressurized air, and may be a machine using a pressurized liquid or a machine using a motor and a feed screw. It is also possible to employ a conventional pressing device, and when it is not necessary to define the position of the support surface of the printed circuit board so accurately, the pressing device itself can be omitted.

Further, the support surface formed on the surface of the semi-fluid substance is usually flat, but may be formed into a curved surface such as a convex cylindrical surface or a concave cylindrical surface for some purpose. The present invention can also be applied to the present invention. If the printed circuit board does not follow the curved supporting surface due to its own weight, means for bending the printed circuit board along the curved surface may be provided.

Further, the printed board supporting method and apparatus of the present invention can be applied not only for supporting a printed board in a screen printing machine but also for other purposes such as supporting a printed board in an electronic component mounting apparatus or a circuit inspection apparatus. It is possible.

In addition, without departing from the scope of the claims, the present invention can be implemented in various modified and improved forms based on the knowledge of those skilled in the art.

[Brief description of the drawings]

FIG. 1 is a front view (partially sectional view) showing a screen printing machine provided with a printed circuit board supporting device according to an embodiment of the present invention.
It is.

FIG. 2 is a side view (partial cross section) of the screen printing machine.

FIG. 3 is an enlarged front sectional view showing a main part of a printed board supporting device of the printed board supporting device.

FIG. 4 is a plan view showing a screen used in the screen printing machine.

FIG. 5 is a front sectional view showing a part of a state where a printed board is brought into contact with the screen.

[Explanation of symbols]

Reference Signs List 30 printed circuit board 70 substrate support 79 container 80 film 81 semi-fluid substance 82 pressurizing device 83 cylinder tube 84 piston 85 volume adjusting chamber 86 pressurizing chamber 92 screen 110, 112 squeegee

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-1-158800 (JP, A) JP-A 2-68500 (JP, U) JP-A 63-91334 (JP, U) (58) Investigation Field (Int. Cl. ⁷ , DB name) H05K 13/00

Claims (5)

(57) [Claims] 1. A supported surface of a printed circuit board is pressed.
If it deforms according to the shape of the supported surface, the pressing force
Using a semi-fluid substance that retains its shape after being released,
A method for supporting a printed circuit board having flexibility, said supported surface of the printed circuit board, the complementary and semifluid its semisolid shaped surface of the supported surface of the material against the surface of the material A method of supporting a printed circuit board, comprising: a forming step of forming a related shape; and a step of supporting a supported surface of the printed board on a surface of the semi-fluid material formed by the forming step. 2. The method according to claim 1, wherein said semi-fluid material undergoes plastic deformation.
Without compromising the shape of the complementary shape
Therefore, covering the semi-fluid substance through the film
The pre-press according to claim 1, wherein the supported surface is supported on a surface.
Support method for the printed circuit board. 3. When pressed against a supported surface of a printed circuit board, it deforms along the shape of the supported surface, and the pressing force is reduced.
A semi-fluid substance that retains its shape even after being released, a support member that can be regarded as substantially rigid and supports the semi-fluid substance, and a presser that faces the semi-fluid substance supported by the support member and the member, the support member and a close together and their pressing member, seen including a moving device for separating the pressing member, the moving instrumentation
The holding member and the supporting member are brought closer by the placement,
The semi-fluid substance is pressed against the supported surface of the printed circuit board.
The printed circuit board is opposite the semi-fluid material when attached
A printed circuit board supporting device that suppresses the bending of the substrate. 4. A has an opening in which the supporting member is opposed to a member holding the a container for accommodating the semifluid material inside the interior of the semi-fluid substance of the container to the container 4. The printed circuit board supporting device according to claim 3 , further comprising a pressurizing device for applying pressure. 5. The semi-fluid material causes a plastic deformation.
Without said deformation Along the surface shape of the semi-fluid material
5. A film as claimed in claim 3 or 4 covered by a film obtained.
Printed circuit board support device.