JP2005159374A - Method for manufacturing holder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a holder which easily handle an object when holding the object such as a circuit board by an adhesiveness. <P>SOLUTION: The method for manufacturing a holder, which holds the circuit board in which an adhesive material for bonding electronic components is printed through a screen mask by a squeegee, has a stage for mounting the adhesive material on the main body of the holder, a stage for heating a metal mold having a plurality of hole parts each bottom face of which is flat or convex shaped, and pressing the metal mold against the adhesive material, and guiding the adhesive material to the bottom face, and a stage for separating the metal mold from the adhesive material after cooling the metal mold. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a technique for holding an object by adhesion, and is applied to, for example, a technique for holding a circuit board when an electronic component is mounted on the circuit board.

  In recent years, sheet-like flexible printed circuit boards (hereinafter referred to as “FPC”) have been used in small electronic devices such as mobile phones, PDAs (Personal Data Assistants), and notebook computers. ing. The FPC is obtained by forming various wiring patterns on a sheet-like resin, and various electronic components such as an IC, a capacitor, a resistor, a coil, and a connector are mounted on the wiring pattern. By using the FPC for an electronic device, a circuit board can be flexibly arranged in the electronic device and the electronic device can be downsized.

  By the way, since FPC has flexibility, it has a disadvantage that it is difficult to handle by itself. In particular, when various electronic components are mounted on the FPC, various processes are performed on the surface of the FPC, and thus it is essential to securely hold the FPC. Therefore, in order to handle an FPC in the same way as an ordinary plate-like circuit board (for example, a circuit board formed of glass epoxy resin), the FPC is fixed on a rigid board using a metal fitting. Is done.

Patent Document 1 discloses a technique in which an adhesive layer is provided on a base plate (base material plate), FPC is adhered to the adhesive layer, and the FPC is handled together with the base plate in the same manner as a normal circuit board.
JP 2002-232197 A

  When an electronic component is mounted on the FPC by adhering the FPC to the base plate, the shape of the adhesive region between the FPC and the base plate and the design of the adhesive force are important. For example, when an electronic component is mounted on an FPC using a solder paste, screen printing of the solder paste on the FPC, mounting of the electronic component, and reflow (heating and cooling) are usually performed. When an adhesive material having a large adhesive force is also present in an area other than the area holding the FPC, the screen mask adheres to the adhesive material during screen printing. Further, when the adhesive force is small, the FPC cannot be adhered and held by the wind pressure due to hot air circulation during reflow. On the contrary, when the adhesive force is large, particularly when the contact area between the adhesive material and the FPC is large, a large force is applied to the FPC at the time of peeling, and it becomes difficult to peel off normally.

  This invention is made | formed in view of the said subject, and it aims at providing the technique which handles a target object easily when holding target objects, such as a circuit board, by adhesion.

The present invention is a method for manufacturing a holder for holding a circuit board on which a viscous material for electronic component bonding is printed through a screen mask by a squeegee,
The holder includes a main body having a base surface formed in a plate shape,
A first holding surface that protrudes on the base surface and holds the screen mask by a plurality of first holding elements whose tip is formed in either a flat shape or a concave shape;
A second holding surface that protrudes on the base surface and holds the circuit board by a plurality of second holding elements whose tip is formed in either a flat shape or a concave shape,
A squeegee that abuts on the circuit board held on the second holding surface and abuts on the screen mask held on the first holding surface is at least one of the first holding surface and the second holding surface. Supported,
The first holding surface, the second holding surface, and the base surface are integrally formed of an adhesive material,
Placing an adhesive material on the main body,
Pressing the pressure-sensitive adhesive material while heating a mold formed with a plurality of holes each having a flat or convex bottom surface, and guiding the pressure-sensitive adhesive material to the bottom surface;
Separating the mold from the adhesive material after cooling the mold.

  In the present invention, it is possible to easily manufacture a holder having a plurality of holding elements for easily handling a flexible object or circuit board by a plurality of holding elements.

  FIG. 1 is a plan view showing a pallet 1 that is a holder when an FPC according to an embodiment of the present invention is conveyed, and FIG. 2 is a cross-sectional view of the pallet 1 at reference numeral 10A in FIG. As shown in FIG. 2, the pallet 1 is a main body member made of a metal such as aluminum or magnesium having high thermal conductivity (may be another material having high rigidity), or a resin such as glass epoxy resin. It has a structure in which an adhesive part 12 formed of an adhesive material is bonded to a plate-like base plate 11 to be. As the adhesive material, silicon rubber is preferably used when heat resistance is required, and polyurethane rubber can also be used when heat resistance is not required. Other adhesive materials may be used if available.

  In FIG. 1, for the convenience of illustration, the region of the adhesive portion 12 is shaded in parallel. 3 is an enlarged view of the area indicated by reference numeral 10B in FIG. 1, and FIG. 4 is a cross-sectional view at reference numeral 10C in FIG. As shown in FIGS. 3 and 4, the adhesive portion 12 includes a base portion 121 bonded to the entire upper surface of the base plate 11 and a number of columnar holding elements 122 protruding from the base surface 1211 which is the upper surface of the base portion 121. The base portion 121 and the plurality of holding elements 122 that are portions including the base surface 1211 are integrally formed of an adhesive material. That is, the plurality of holding elements 122 are provided so as to protrude from the main body 110 constituted by the base plate 11 and the base part 121. Each holding element 122 has a flat holding surface 1221 at the tip for adhering FPC, which is a flexible circuit board.

  3 and 4, the holding element 122 has a diameter of 1.2 mm and a height of 1.5 mm, and the holding element 122 has a pitch of 2 mm with respect to the X direction in FIG. The case where the distance of the Y direction between the centers of the arrangement | sequence is 2 mm is illustrated.

  As shown in FIG. 1, the pallet 1 is formed with a positioning through hole 30a, and is also formed with a through hole 30b for positioning the FPC to be held. Furthermore, as shown in FIG. 1 and FIG. 2, a large number of through-holes 31 into which a protruding pin for peeling the held FPC is inserted are also formed.

  FIG. 5 is a plan view showing a state in which the FPC 9 is held on the pallet 1. The back surface (the surface to be held) of the FPC 9 is flat, and the FPC 9 is reliably held by the holding surfaces 1221 of the plurality of holding elements 122 having the same height from the base surface 1211 that is a flat surface. Note that the FPC 9 is formed with a plurality of FPC piece 91 wirings, and each FPC piece 91 has an IC package (the mounting target is various electronic devices such as an IC bare chip, a capacitor, a resistor, a coil, and a connector). It may be a component and is hereinafter collectively referred to as “electronic component”). Positioning holes 90 are formed at the four corners of the FPC 9 so as to overlap the FPC through holes 30 b shown in FIG. 1, and the through holes 31 for the protruding pins are located between the FPC pieces 91.

  6 and 7 are front views showing the mounting system 5 that mounts electronic components on the mounting area 91a of the FPC piece 91 in a state in which the FPC 9 is held on the pallet 1. FIG. The mounting system 5 includes, from upstream, a loader 51 for mounting the FPC 9 on the pallet 1, a printing device 52 for printing solder paste on the FPC 9, a mounting device 53 for mounting electronic components on the FPC 9, and melting and solidifying the solder paste. A reflow device 54 for fixing electronic components to the FPC 9, an unloader 55 for peeling the FPC 9 from the pallet 1, and a cleaning device 56 for cleaning the pallet 1 are provided. A conveyor 61 for the outward path of the pallet 1 is arranged at the center of each apparatus, and a conveyor 62 for the return path is arranged at the lower part of each apparatus.

  In the loader 51, a plurality of trays 951 are stacked in the vertical direction and stored in the storage device 95, and the FPC 9 is placed on each tray 951. The loader 51 includes an elevating mechanism 511 that moves the storage device 95 up and down, a protruding mechanism 512 that takes in and out one tray 951 from the storage device 95, a transfer mechanism 513 that extracts the FPC 9 from the protruding tray 951 by suction, and a pallet. 1 is provided with a pallet moving mechanism 514 for moving 1 from the end point of the return path conveyor 62 to the start point of the forward path conveyor 61.

  The holding surface 5131 for holding the FPC 9 of the transfer mechanism 513 is a flat surface on which many suction ports are formed. The transfer mechanism 513 takes out the FPC 9 from the tray 951 by suction suction, and then puts it on the pallet 1 on the conveyor 61. The FPC 9 is placed. At this time, positioning is performed with reference to the through hole 30b of the pallet 1 and the hole 90 of the FPC 9, and the holding surface 5131 is lowered to press the entire FPC 9 toward the pallet 1 with a predetermined pressure. Thereby, the entire FPC 9 is held by the adhesive on the adhesive portion 12 of the pallet 1 (more precisely, the holding surface 1221 of the holding element 122). The pallet 1 holding the FPC 9 is conveyed to the printing device 52 by the conveyor 61.

  The printing device 52 positions and holds the pallet 1 with respect to the positioning through hole 30a (see FIG. 1) as a reference (that is, by inserting a pin) and pushes it up toward the upper screen mask 522, A printing mechanism 523 for reciprocating the solder paste on the screen mask 522 with a squeegee 5231 is provided. When the printing mechanism 523 reciprocates the squeegee 5231 while the FPC 9 on the pallet 1 is in contact with the screen mask 522, the solder paste adheres to the FPC 9 from the holes formed in the screen mask 522. The FPC 9 on which the solder paste is printed descends together with the pallet 1 and is conveyed to the mounting device 53 by the conveyor 61.

  The mounting device 53 includes a holding mechanism 531 that holds the pallet 1 with the through hole 30 a as a reference, and a mounting mechanism 532 that mounts an electronic component on the FPC 9 on the pallet 1. The mounting mechanism 532 has a plurality of nozzles 5321 for sucking and adsorbing electronic components, and a nozzle moving mechanism 5322 for moving the nozzle 5321 in the horizontal plane and moving up and down, and a supply mechanism (not shown) (on the tape or The electronic component is received from a mechanism for arranging and preparing the electronic component on the tray), and the electronic component is mounted on the solder paste on the FPC 9. The FPC 9 on which the electronic components are mounted is conveyed along with the pallet 1 to the reflow device 54 shown in FIG.

  The reflow device 54 includes a heating unit 541 that performs preheating and main heating on the FPC 9 that is conveyed by the conveyor 61 while being held on the pallet 1, and a cooling unit 542 that cools the FPC 9 with air. The FPC 9 is heated and cooled while being conveyed, the solder paste is melted and solidified, and the electronic component is fixed onto the FPC 9. As shown in FIG. 5, since the entire FPC 9 is in a state of being adhered to the adhesive part 12 of the pallet 1, even when heating with hot air or cooling with cold air is performed, a part of the FPC 9 is removed from the adhesive part 12. It is prevented from peeling off. After the reflow, the FPC 9 is transported to the unloader 55 together with the pallet 1.

  The unloader 55 includes a holding mechanism 551 that holds the pallet 1, a transfer mechanism 552 that receives the FPC 9 from the pallet 1, an elevating mechanism 553 that raises and lowers the storage device 96 that stores the FPC 9, and a protruding mechanism that takes in and out the tray from the storage device 96. (Not shown). The storage device 96 has a plurality of trays stacked vertically, and the protruding mechanism protrudes the tray. The transfer mechanism 552 receives the FPC 9 from the pallet 1 and places the FPC 9 on the tray, and then the protruding mechanism stores the tray. Pull into vessel 96.

  FIGS. 8 and 9 are diagrams for explaining how the transfer mechanism 552 receives the FPC 9 from the pallet 1. A protrusion pin 641 for peeling the FPC 9 is disposed inside the holding mechanism 551, and the protrusion pin 641 protrudes from the holding surface 5511 when the shaft 642 rises. The holding mechanism 551 is positioned with reference to the positioning through-hole 30a (see FIG. 1) to hold the pallet 1, and the protruding pin 641 and the through-hole 31 coincide (see FIGS. 1 and 2).

A recess 651 for avoiding the electronic component 92 mounted on the FPC 9 is formed on the holding surface 5521 (lower surface) on the transfer mechanism 552 side, and a suction port for sucking and adsorbing the FPC 9 to the holding surface 5521 is further provided. 652 is formed, and a suction channel 653 is formed inside.

  When the transfer mechanism 552 receives the FPC 9, first, as shown in FIG. 8, the holding surface 5521 of the transfer mechanism 552 descends and comes into contact with the FPC 9, and suction starts from the suction port 652 on the transfer mechanism 552 side. Is done. Next, the shaft 642 of the holding mechanism 551 rises, and the thrust pin 641 pushes up the FPC 9. At this time, the holding surface 5521 of the transfer mechanism 552 rises as shown in FIG. 9 in synchronization with the movement of the protrusion pin 641, and the FPC 9 is completely peeled off from the adhesive portion 12 of the pallet 1. The holding surface 5521 is adsorbed.

  The pallet 1 from which the FPC 9 has been peeled is conveyed to a cleaning device 56 by a conveyor 61 as shown in FIG. The cleaning device 56 includes a cleaning mechanism 561 that cleans the pallet 1 and a pallet moving mechanism 562 that moves from the end point of the forward path conveyor 61 to the start point of the return path conveyor 62. The cleaning mechanism 561 unwinds the cloth from the cloth roll 5611 wound around the cloth to which the cleaning liquid is applied, contacts the cloth against the adhesive portion 12 of the pallet 1 with the roller 5612, and then winds the cloth around the shaft 5613. to recover. Thereby, the dust adhering to the adhesion part 12 is removed. The cleaned pallet 1 is lowered by the pallet moving mechanism 562 and moved to the conveyor 62, conveyed from the cleaning device 56 to the loader 51, and moved to the conveyor 61 by the pallet moving mechanism 514 of the loader 51.

  As described above, since the pallet 1 substantially holds the entire FPC 9 with adhesive, it is possible to prevent the FPC 9 from being peeled off from the pallet 1 when electronic components are mounted.

  On the contrary, as shown in FIGS. 3 and 4, in the pallet 1, a large number of holding elements 122 are arranged on the main body 110 with gaps, so that peeling can be easily performed. Although the exact principle on which peeling is easily performed is not necessarily clear, when the FPC 9 is peeled from the pallet 1, the peeling boundary is in a finely cut state, and the peeling from one holding surface 1221 takes a short time. (That is, peeling is performed intermittently), the force acting on the peeling boundary on the bottom surface of the FPC 9 is dispersed both geometrically and temporally, and a large force is temporarily concentrated on the FPC 9. This is thought to be due to the suppression.

  Moreover, since the holding surface 1221 of each holding element 122 is circular, even if the peeling of the FPC 9 proceeds in any direction, the peeling is easily started from a local site on the holding surface 1221. . Accordingly, it can be said that the FPC 9 is easily peeled even when attention is paid to the individual holding surfaces 1221.

  Further, since the plurality of holding elements 122 protruding from the main body 110 have elasticity, as shown in FIG. 10, the influence of the difference in thermal expansion that occurs between the FPC 9 and the pallet 1 due to heating during reflow is illustrated. Absorption is also realized by the deformation of. As a result, the FPC 9 can be reliably held by the pallet 1 during reflow. In particular, in recent years, large FPCs including a large number of FPC pieces are often handled, and the difference in thermal expansion between the FPC and the pallet when processing involving heating such as reflow is performed is large. Prevention of peeling of the FPC due to deformation is important.

  The shape and arrangement of the holding elements 122 are appropriately changed according to the size of the FPC to be held and the type of processing to be performed on the FPC, but the width (specifically, When the width and the width of the circuit board are 10 mm or more and 350 mm or less, the diameter of the holding element 122 is preferably 1 mm or more and 30 mm or less, and the height is 0.1 mm or more and 5 mm or less. Is preferred. Furthermore, when heating is performed as in reflow processing (especially when the width of the circuit board is 100 mm or more and 350 mm or less), the influence of the difference in thermal expansion between the FPC and the pallet 1 is absorbed. Therefore, it is preferable that the holding element 122 has a diameter of 1 mm to 3 mm and a height of 0.5 mm to 5 mm. The above conditions are suitable for a rubber having an Hs hardness of 20 or more and 50 or less, and the Hs hardness of the rubber itself is most preferably about 30.

  Next, a method for manufacturing the pallet 1 will be described. FIG. 11 is a diagram showing a flow of the manufacturing process of the pallet 1, and FIGS. 12 to 15 are diagrams showing how the pallet 1 is manufactured.

  First, as shown in FIG. 12, a mold 71 for forming the holding element 122 is prepared and attached to the press device 72. The press device 72 is provided with a heater 73, and the die 71 is heated in advance by the heater 73 (step S11).

  When the preparation of the press device 72 is completed, a release agent is applied to the mold 71 (step S12), a primer (adhesive) is applied onto the base plate 11, and an adhesive material 12a (for example, a rubber sheet) is placed thereon. (Liquid adhesive material may be applied). (Step S13). Note that a release agent may be applied to the adhesive material 12a after step S13.

  FIG. 13 is an enlarged cross-sectional view of the lower surface 71a of the mold 71 and the adhesive material 12a adjacent to the lower surface 71a. A large number of cylindrical holes 701 for forming a plurality of holding elements 122 are formed on the lower surface 71a of the mold 71, and the bottom surface 702 of each hole 701 is planar.

  Next, as shown in FIG. 14, the adhesive material 12 a is heated and pressed by a mold 71 at a predetermined temperature and force for a certain period of time to a shape corresponding to the uneven pattern on the lower surface 71 a of the mold 71. The surface of the adhesive material 12a is deformed (step S14). FIG. 15 is an enlarged cross-sectional view showing the lower part of the pressed mold 71 and the adhesive material 12a. As shown in FIG. 15, the adhesive material 12 a becomes a fluid due to heat, and is sufficiently guided to the bottom surface 702 while extruding air in each hole 701 of the mold 71. The rubber sheet, which is the adhesive material 12a, is premixed with sulfur and other additives, and vulcanization (referred to as primary vulcanization) of the adhesive material 12a is performed simultaneously by heating during pressing.

  Thereafter, when the mold 71 is cooled in the state shown in FIG. 15 and the adhesive material 12a is cured (returns to the elastic body), the mold 71 rises and the mold 71 is separated from the adhesive material 12a. (Step S15), a large number of cylindrical holding elements 122 shown in FIG. 4 are obtained. Since the bottom surface 702 of the hole 701 is a flat surface, the front end surface of each holding element 122 is a flat surface that adheres to the FPC 9 accurately. Furthermore, various through holes of the pallet 1 are formed as necessary.

  As described above, the large number of holding elements 122 of the pallet 1 can be easily formed in a short time simply by pressing the heated mold 71 against the adhesive material 12a. The mold 71 may incorporate a mechanism for forming various through holes of the pallet 1 simultaneously with the formation of the adhesive portion 12.

  Further, when the columnar holding element 122 is formed, since the shape of the hole 701 (side surface thereof) is cylindrical, the hole 701 is easily and efficiently formed using an end mill when the mold 71 is manufactured. can do. Thereby, reduction of the manufacturing cost of the metal mold | die 71 is implement | achieved. As another example of the hole that can be easily formed by a tool, there can be mentioned one having a shape in which the four corners are chamfered circularly when the hole is viewed from the opening side.

FIG. 16 is a plan view showing another example of the pallet 1. In the pallet 1, the size and arrangement of the holding elements are different from each other in the first holding region 21 at the peripheral portion of the adhesive portion 12 and the second holding region 22 in the central portion as compared with the one shown in FIG. 1. Other configurations are the same as those of the pallet 1 of FIG. 1 and are denoted by the same reference numerals as those of FIG. In FIG. 16, differences in the size and arrangement of the holding elements are indicated by different parallel oblique lines for convenience.

  In the first holding region 21, a plurality of holding elements 122 similar to those shown in FIG. 3 are formed. On the other hand, the holding elements are arranged at a higher density in the second holding region 22. FIG. 17 is an enlarged view of the area indicated by reference numeral 10D in FIG. As shown in FIG. 17, columnar holding elements 122a having a large diameter and columnar holding elements 122b having a relatively small diameter are alternately arranged. The holding elements 122a have a diameter of 1.5 mm and are arranged with a pitch of 2 mm. The diameter of the holding element 122b is 1 mm, and each holding element 122b is arranged between the four holding elements 122a. The heights of the holding elements 122, 122a, and 122b from the base surface 1211 (see FIG. 4) are the same, and the flat FPC 9 can be reliably held.

  By arranging the holding elements in the first holding region 21 and the second holding region 22 as described above, the holding elements 122 are arranged in the first holding region 21 so that the area of the holding surface which is the tip surface of the holding element 122 is arranged. The area of the area is 28.3%, and in the second holding area 22, the area of the holding surfaces of the holding elements 122a and 122b is 63.8% of the area of the area where the holding elements 122a and 122b are arranged. As a result, the degree of adhesion can be adjusted by the ratio of the area of the holding surface per unit area, and the degree of adhesion in the second holding region 22 is higher than that of the first holding region 21. The degree of adhesion is a value corresponding to a load required for peeling after an object is adhered under predetermined conditions, and is a value indicating the degree of adhesion.

  Further, in the second holding region 22, it is easy to increase the ratio of the area of the holding surface by the holding elements having different diameters compared to the case where the holding elements having the same diameter are arranged.

  18 is a plan view showing a state in which the same FPC 9 as in FIG. 5 is held on the pallet 1 shown in FIG. 16, and the same reference numerals as those in FIG. 5 are given. The peripheral portion of the FPC 9 overlaps with the first holding region 21, and the second holding region 22 overlaps with the central portion of the FPC 9. Accordingly, the area where the FPC 9 is not held is only the first holding area 21 with a low degree of adhesion, and the screen mask 522 is weakly adhered to the first holding area 21 when the solder paste is printed in the mounting system 5 shown in FIGS. . As a result, the screen mask 522 can be easily brought into and out of contact with the pallet 1.

  On the other hand, since the center portion of the FPC 9 is strongly held by the second holding region 22 and the FPC 9 is held by the first holding region 21 up to the peripheral portion, the separation of the FPC 9 due to the airflow during reflow is prevented. Further, since the FPC 9 is held by a large number of holding elements arranged with gaps, as in the case of the pallet 1 in FIG. 1, the separation can be easily performed and the difference in thermal expansion between the FPC 9 and the pallet 1 can be reduced. Absorbing the effect is realized.

  The method of manufacturing the pallet 1 shown in FIG. 16 is the same as that of the pallet 1 shown in FIG. 1 except that the hole of the mold is changed according to the holding elements of the first holding region 21 and the second holding region 22. Same as the case.

FIG. 19 is a plan view showing still another example of the pallet 1. The pallet 1 holds a plurality of FPC pieces individually. The pallet 1 includes a first holding region 21 having a low adhesiveness in which the holding elements 122 shown in FIG. 3 are formed, and holding elements 122a and 122b shown in FIG. A plurality of combinations of the second holding regions 22 that are formed and have a relatively high degree of adhesion are provided. In FIG. 19, the surface of the base plate 11 is exposed in a region not provided with parallel oblique lines, and the adhesive portion is formed only in the first holding region 21 and the second holding region 22 indicated with parallel oblique lines. The first
A plurality of through holes 31 into which the protruding pins are inserted are formed in the holding region 21.

  FIG. 20 is a plan view showing the appearance of the FPC piece 91 held on the pallet 1. The FPC piece 91 has a shape in which the lead portion 912 protrudes from the mounting portion 911. The mounting portion 911 includes a mounting region 91b where an IC package is mounted and a mounting region 91c where a resistor, a capacitor, and the like are mounted. Is set.

  FIG. 21 is a plan view showing a state in which a plurality of FPC pieces 91 are adhesively held on the pallet 1. As shown in FIG. 21, the mounting portion 911 of the FPC piece 91 is held in a region where the two second holding regions 22 are included in the first holding region 21, and the leading end of the lead portion 912 is a small second holding region 22. Retained.

  The manner in which electronic components are mounted on the FPC pieces 91 using the pallet 1 shown in FIG. 19 is the same as the case of the pallet 1 shown in FIG. 1 except that a plurality of FPC pieces 91 are held on the pallet 1. It is the same. By using the pallet 1, almost the entire FPC piece 91 is held by adhesion, and it is possible to prevent the FPC piece 91 from being peeled off from the pallet 1 when electronic components are mounted. In particular, since the lead portion 912 is held in the second holding region 22 having a high degree of adhesion, peeling of the FPC piece 91 from the lead portion 912 is prevented. Further, since most of the area where the FPC pieces 91 are not held does not have adhesiveness, screen printing can be easily performed.

  By the way, in the pallet 1 shown in FIG. 19, a through hole 31 for a protruding pin is provided in the first holding region 21. Accordingly, when the FPC piece 91 is peeled from the pallet 1, an excessive force acts on the FPC piece 91 by performing mechanical peeling from the first holding region 21 having a low degree of adhesiveness with the protruding pin. Peeling can be performed smoothly without any problems. As a result, easy peeling of the FPC piece 91 is realized while the second holding region 22 has a degree of adhesion that reliably holds the FPC piece 91.

  Further, by holding the FPC 9 by a large number of holding elements arranged with gaps, as in the case of the pallet 1 in FIG. 1, the separation can be easily performed and the difference in thermal expansion between the FPC 9 and the pallet 1 can be reduced. Absorbing the effect is realized. Further, the mounting portion 911 of the FPC piece 91 is held in the first holding area 21 and the second holding area 22 existing in one area of the adhesive material, and the second holding area 22 is held in the first holding area 21. Since it is included, it is also possible to smoothly peel the FPC piece 91 from the peripheral edge (the same applies to the pallet 1 in FIG. 16).

  The method of manufacturing the pallet 1 shown in FIG. 19 is the same as that of the pallet 1 shown in FIGS. 1 and 16 except that the adhesive portion is provided on a part of the surface of the base plate 11.

  22 is a longitudinal sectional view showing a part of still another example of the pallet 1, and FIG. 23 is an enlarged view of the pallet 1 shown in FIG. The pallet 1 shown in FIG. 22 has a base plate 11 and an adhesive portion 12 as in the pallet 1 shown in FIG. 1, but as shown in FIG. 23, a cylindrical holding element 122c having a different height from the flat base surface 1211. , 122d protrudes. That is, the adhesive part 12 is substantially provided with a step. Further, as shown in FIG. 22, a through-hole 31 into which a peeling pin 641 for peeling is inserted is appropriately formed through the base plate 11 and the adhesive portion 12.

A reinforcing member 93 is bonded to the FPC 9 held on the pallet 1 on the back surface (the surface facing the pallet 1) opposite to the surface on which the electronic component 92 is mounted as shown in FIG. The circuit board has flexibility. As shown in FIG. 23, the thickness of the reinforcing member 93 is equal to the difference in height between the holding element 122c and the holding element 122d, and the FPC 9 is held on the pallet 1 without being affected by the reinforcing member 93. Further, the pallet 1 holds almost the entire FPC 9 with adhesive, and the FPC 9 is prevented from being peeled off from the pallet 1 when electronic components are mounted.

  Also in the case of the pallet 1 shown in FIG. 22, by holding the FPC 9 with a large number of holding elements arranged with gaps, as in the case of the pallet 1 in FIG. Absorption of the influence of the difference in thermal expansion with the pallet 1 is realized.

  The area ratio of the holding element 122c that adheres the FPC 9 main body may be different from the area ratio of the holding element 122d that adheres the reinforcing member 93. For example, when it is necessary to completely prevent the FPC 9 from being peeled off during mounting, the degree of adhesion of a region having a high step corresponding to the peripheral portion of the FPC 9 (that is, a region where the holding element 122c is provided) is set to be relatively high. Is done. Further, when the dent of the protrusion pin 641 remains on the FPC 9 when the reinforcing member 93 is strongly adhered, the degree of adhesion of the low step region (that is, the region where the holding element 122d is provided) is set low.

  Furthermore, the height of the holding element from the base surface 1211 is not limited to two, and may be three or more. By setting the height of each holding element from a plurality of heights, accurate holding according to the shape of the circuit board is realized.

  The manufacturing method of the pallet 1 shown in FIG. 22 is the same as that of the pallet 1 shown in FIG. 1 except that holding elements having different heights are formed.

  FIG. 24 is a plan view showing a modification of the pallet 1 shown in FIG. The pallet 1 shown in FIG. 24 is obtained by reversing the relationship between the first holding area 21 and the second holding area 22 as compared with the pallet 1 shown in FIG. 1st holding | maintenance area | region 21 with low adhesiveness is included. However, the portion of the second holding region 22 that protrudes from the FPC 9 is minimized so that the screen mask is not strongly adhered to the pallet 1 when the solder paste is printed. In the pallet 1 shown in FIG. 24, it is possible to remarkably reduce the peripheral portion of the FPC 9 from being peeled from the adhesive portion 12 during reflow, and the FPC 9 can be easily handled during reflow. In this way, whether the holding area corresponding to the peripheral edge of the FPC 9 is increased or decreased (more generally, how to provide a plurality of areas having different ratios of the area of the holding surface per unit area) Is appropriately determined according to the characteristics of the FPC 9 and the type of processing.

  FIG. 25 is a plan view (corresponding to FIG. 3) showing another example of the holding element. The holding element 122e shown in FIG. 25 has a prismatic shape, and the holding surface 1221 has a rectangular shape that is long in the Y direction (the vertical direction of the paper) in FIG. Thereby, each holding element 122e has the characteristic that it is easy to bend in the X direction (left and right direction of the paper surface) and is not easily bent in the Y direction. As a result, for example, when an FPC that easily expands in the X direction is held, it is realized that the holding element 122e bends and easily absorbs the influence of the difference in thermal expansion between the pallet and the FPC.

  FIG. 26 is a cross-sectional view showing still another example of the holding element, and also shows a cross section of a mold 71 for forming the holding element. In the holding element 122f shown in FIG. 26, the holding surface 1221 at the tip is slightly concave. Thus, when the FPC 9 is pressed against the holding element 122f, the holding surface 1221 adsorbs the FPC 9 by the same action as the suction cup, and the FPC 9 is more strongly held. In addition, in order to form the holding element 122f, the bottom surface 702 of the hole 701 formed in the mold 71 is convex.

FIG. 27 is a longitudinal sectional view showing still another example of the holding element, and the holding element 122g of FIG. 27 has a truncated cone shape. Thereby, compared with the case of the holding element 122 shown in FIG. 4, the area of one holding surface 1221 can be made small, and adhesiveness can be reduced, without making a holding element excessively thin. The holding element may be arbitrarily changed as long as it can be separated from the mold after molding. For example, the holding element may have a shape in which thin cylinders are stacked on a thick cylinder.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and various modifications can be made.

  For example, the pallet 1 is suitable for holding a flexible circuit board such as a polyimide film or a very thin glass epoxy resin, but the held circuit board may be a plate-like circuit board having a certain degree of rigidity. Good. In addition, the holding of the circuit board by adhesion is not only applied to the pallet 1 for conveyance, but can also be used as a holder in various aspects of handling the circuit board. Of course, the above-described adhesive holding method can be used in fields other than mounting electronic components using solder paste, anisotropic conductive resin, or the like, for example, when holding a circuit board when processing the circuit board.

  In the pallet 1 in the above embodiment, an adhesive material is provided on the base plate 11, but it is also possible to manufacture a holder by processing a member having adhesiveness. For example, the holding element may be provided by forming a large number of holes in the base plate 11 of the pallet 1 and inserting a cylindrical adhesive material into these holes. Further, a plurality of holding elements may be formed by attaching a rubber sheet, which is an adhesive material, to the base plate 11 and forming a plurality of intersecting grooves in the rubber sheet.

  In the pallet 1 shown in FIG. 16 and FIG. 19, two areas of adhesiveness are provided by changing the ratio per unit area of the holding surface of the holding element, but even if three or more areas having different adhesiveness are provided. Good. In other words, by adjusting the diameter of at least one cylindrical holding element to be different from the diameter of any other holding element, adjustment of the degree of adhesion for each region is realized. In general, the degree of adhesion is adjusted by adjusting the ratio of the area of the holding surface per unit area, so that the shape or size of the holding surface of at least one holding element can be It can be said that the adhesiveness is adjusted by making the holding surface different from that of the holding element.

  Furthermore, the object to be held may be other than the circuit board. In particular, by holding a sheet-like or thin-plate-like flexible object (which may be only partially flexible), by applying the technique of holding with a number of holding elements described above, Easy handling of the object is realized.

  In the above embodiment, the holding element is formed by pressing the mold 71 perpendicularly to the adhesive material 12a. However, as shown in FIG. 28, the mold 71 has a roller shape in which a large number of holes 701 are formed. The holding element 122 may be continuously formed on the adhesive material 12a while rotating the mold 71 and the opposing roller 71b.

  In this invention, it can utilize for holding | maintenance of FPC etc. in the mounting process which attaches an electronic device to FPC etc.

Pallet top view Pallet cross section Enlarged view of part of the pallet Cross section of part of the pallet Top view showing how FPC is held on the pallet Front view of mounting system Front view of mounting system The figure for demonstrating a mode that a transfer mechanism receives FPC from a pallet. The figure for demonstrating a mode that a transfer mechanism receives FPC from a pallet. Diagram showing deformation of holding element Diagram showing the flow of pallet manufacturing process Diagram showing how pallets are manufactured Enlarged view showing mold and adhesive material Diagram showing how pallets are manufactured Enlarged view showing mold and adhesive material Top view of other pallets Enlarged view of part of the pallet Top view showing how FPC is held on the pallet Plan view of yet another pallet Plan view of FPC piece The top view which shows a mode that the FPC piece was hold | maintained on the pallet Cross section of yet another pallet Cross section of part of the pallet Plan view showing a modification of the pallet Top view of other holding elements Cross section of yet another holding element and mold Cross section of yet another holding element The figure which shows a mode that a holding element is formed continuously

Explanation of symbols

1 Palette 9 FPC
12a Adhesive material 21 First holding region 22 Second holding region 31 Through hole 71 Mold 110 Main body portion 121 Base portion 122, 122a to 122g Holding element 701 Hole portion 702 Bottom surface 1211 Base surface 1221 Holding surface S13 to S15 Steps

Claims (3)

A method of manufacturing a holder for holding a circuit board on which a viscous material for electronic component bonding is printed through a screen mask by a squeegee,
The holder includes a main body having a base surface formed in a plate shape,
A first holding surface that protrudes on the base surface and holds the screen mask by a plurality of first holding elements whose tip is formed in either a flat shape or a concave shape;
A second holding surface that protrudes on the base surface and holds the circuit board by a plurality of second holding elements whose tip is formed in either a flat shape or a concave shape,
A squeegee that abuts on the circuit board held on the second holding surface and abuts on the screen mask held on the first holding surface is at least one of the first holding surface and the second holding surface. Supported,
The first holding surface, the second holding surface, and the base surface are integrally formed of an adhesive material,
Placing an adhesive material on the main body,
Pressing the pressure-sensitive adhesive material while heating a mold formed with a plurality of holes each having a flat or convex bottom surface, and guiding the pressure-sensitive adhesive material to the bottom surface;
And a step of separating the mold from the adhesive material after the mold is cooled.   The method for manufacturing a holder according to claim 1, wherein the adhesive material is one of silicon rubber and polyurethane rubber. The method for manufacturing a holder according to claim 2, wherein vulcanization is performed in the step of guiding the viscous material to the bottom surface.

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