JP4891181B2 - Method for manufacturing contact for variable resistor - Google Patents

Description

  The present invention relates to a method for manufacturing a contact for a variable resistor using a carbon fiber plate having conductivity formed in a plate shape using carbon fiber and synthetic resin as main raw materials.

  In FIG. 2 of Japanese Patent Laid-Open No. 2003-51361 (Patent Document 1), one or more prepreg thermosetting resins made into a plate shape by impregnating a plurality of carbon fibers with a thermosetting insulating resin are heated. There is disclosed a contact for a variable resistor in which a slit is formed in a cured carbon fiber sheet.

In this contact for a variable resistor, the contact piece has a structure in which a large number of carbon fibers are hardened in a plate shape with a thermosetting resin. For this reason, even when the contact is repeatedly driven, there is an advantage that the contact and the resistor are less worn and the life of the variable resistor is extended.
Japanese Patent Laying-Open No. 2003-51361 (FIG. 2)

  Patent Document 1 does not show a specific manufacturing method for forming a slit. Considering from common technical knowledge at the time, it can be inferred that the slits are formed by press working. However, when slits are formed by press working, burrs are generated around the slits by punching out the press, and a process of removing the burrs and finishing the surface is necessary. There are various methods for forming slits other than pressing. For example, end mill processing, wire electric discharge processing, laser processing, water processing and the like can be considered. However, end mill processing is not suitable for mass production because the frequency of tool replacement is high. Further, in wire electric discharge machining and laser machining, since the cooling of the machined portion is difficult, the resin near the slit is altered by machining heat. Furthermore, water processing is expensive in equipment, and the final manufacturing cost is high.

  An object of the present invention is to provide a method for manufacturing a contact for a variable resistor that can easily form slits in a large number of contact forming plates in a short time without generating burrs.

  Another object of the present invention is to provide a method for manufacturing a contact for a variable resistor, which can reduce the frequency of tool replacement, suppress deterioration of the resin in the vicinity of the slit, and form the slit with inexpensive equipment.

  The manufacturing method of the variable resistor contact according to the present invention includes first to fourth steps. In the first step, a plurality of contact-forming plate materials having the same shape formed from conductive carbon fiber plates formed in a plate shape using carbon fibers and synthetic resin as main raw materials are prepared. In the second step, a plurality of contactor forming plate members are stacked in the thickness direction of the contactor forming plate member to form a laminate. In the third step, one or more slits are formed by dicing that open on one stack surface of the stack and extend in the stacking direction of the stack and open on both side surfaces of the stack in the stacking direction. In the fourth step, the contact forming plate is separated from the laminated body after dicing to obtain a variable resistor contact. Here, the dicing process is a cutting process performed by rotating a disk-shaped blade in which diamond abrasive grains are embedded in a binding material made of a resin bond, a metal bond, or the like. The dicing process is employed for cutting a wafer and the like, and the cutting process can be performed accurately without generating burrs.

  If slits are formed by dicing on a laminate of a plurality of contactor forming plate members as in the present invention, slits are formed in a lump without generating burrs in a laminate of a large number of contactor forming plate members. can do. Therefore, there is no need for a step of removing burrs and finishing the surface as in the prior art, and slits can be easily formed in a large number of contact forming plates in a short time. Further, since the frequency of tool exchange is not high as in end milling, mass production of contacts can be performed. Further, in the wire electric discharge machining and the laser machining, it is difficult to cool the processed portion, whereas in the dicing machining, the cooling with the machining liquid is possible, and the deterioration of the resin due to the processing heat can be suppressed. In addition, the equipment cost is low compared to water processing. Furthermore, in these other methods, even if a slit is formed in a laminate of a plurality of contactor forming plate members, the number of contactor forming plate members to be stacked is limited. If the slits are formed by dicing as in the present invention, the slits can be formed in a lump even if a laminated body is formed by laminating a large number of contact forming plate materials. Slit formation of the contactor forming plate can be performed.

  When the number of slits is plural, in the third step, a plurality of dicing blades may be used and a plurality of slits arranged in parallel at the same time may be formed in the laminate. In this way, even if there are a plurality of slits, slits can be formed in a large number of contact forming plate materials in a short time.

  The contact forming plate prepared in the first step has a rectangular shape in outline, and the laminate formed in the second step preferably has a cubic shape or a rectangular parallelepiped shape. If the contact forming plate material has a rectangular outline, a plurality of contact forming plate materials can be easily formed from the carbon fiber plate. Further, if the laminate has a cubic shape or a rectangular parallelepiped shape, the laminate can be easily held when the slit is formed.

  Further, before or after the third step, machining for collectively forming through holes or recesses used for attachment can be performed on the laminate. If it does in this way, the through-hole or recessed part used for attachment can be collectively formed in a short time in many board | plates for contactor formation.

  In the fourth step, after separating the contact forming plate material from the laminate, the chamfering of the contact portion that contacts the sliding resistor of the variable resistor of the contact forming plate material can be performed by dicing. In this way, chamfering can be easily performed without generating burrs.

  The variable resistor contact manufactured by the method of the present invention has no burrs and high dimensional accuracy.

  According to the manufacturing method of the present invention, slits are formed by dicing in a laminate of a plurality of contactor forming plate members, so that a plurality of contactor forming plate member laminates do not generate burrs all at once. A slit can be formed. Therefore, there is no need for a step of removing the burrs and finishing the surface, and slits can be easily formed in a large number of contact forming plate materials in a short time.

  The best mode of the production method of the present invention will be described below with reference to the drawings. First, the variable resistor contact manufactured by the method of the embodiment of the present invention will be briefly described. FIG. 1 is a plan view of a contact for a variable resistor (hereinafter simply referred to as a contact) manufactured by the method of an embodiment of the present invention, and FIG. 2 is a variable resistor to which the contact shown in FIG. 1 is attached. It is a side view of a vessel. As shown in FIG. 1, the contact 1 has a contact base 3 and four contact pieces 5 </ b> A to 5 </ b> D. The contact 1 is formed by using a carbon fiber plate made mainly of carbon fibers and a synthetic resin, which will be described later, as raw materials. The contact base 3 of the contact 1 has a rectangular shape and a circular through hole 3a at the center. The contact pieces 5 </ b> A to 5 </ b> D have an elongated rectangular shape and extend in parallel from the contact base 3. Of the four contact pieces 5A to 5D, a central slit portion 7A is formed between two adjacent contact pieces 5B located at the center and the contact piece 5C. Of the four contact pieces 5A to 5D, a side slit portion 7B is formed between two adjacent contact pieces 5A located on one side and the contact piece 5B, and the other side. A side slit portion 7 </ b> C is formed between two adjacent contact piece 5 </ b> C and the contact piece 5 </ b> D that are located on the sides of the contact piece 5 </ b> D. The side slit portion 7B and the side slit portion 7C have substantially the same shape and size, and have a width dimension shorter than that of the central slit portion 7A. Each of the contact pieces 5A to 5D of the contact 1 has a contact portion 5a that comes into contact with a sliding resistor 11 described later (see FIG. 2). The contact portion 5a is configured by a corner portion between the front end surface 5b and the side surface 5c. It is also possible to chamfer the corners and use the processed tip as a contact part.

  As shown in FIG. 2, the contact 1 is attached to the holder 9 as a component of the variable resistor. In this example, after the fixing member 9a of the holder 9 is fitted into the through hole 3a of the contact 1, the tip of the fixing member 9a is deformed so as to be crushed by welding, so that the contact 1 is attached to the holder 9. Yes. In a state where the contact 1 is held by the holder 9, the contact portions 5 a of the contact pieces 5 </ b> A to 5 </ b> D of the contact 1 are in contact with the sliding resistor 11. Thereby, the contact pieces 5A to 5D slide on the sliding resistor 11 by the operation of the holder 9, and the resistance value of the variable resistor changes.

  Next, the manufacturing method according to the embodiment of the present invention will be described. First, as shown in FIG. 3, a rectangular carbon fiber plate 21 is prepared. The carbon fiber plate 21 is formed into a plate shape using carbon fibers and synthetic resin as main raw materials, and has conductivity. In this example, the carbon fiber plate 21 has a cross-sectional shape shown in FIG. 4, and is configured by laminating a plurality of (three in this example) prepregs 23. The prepreg 23 is formed in a plate shape by impregnating a plurality of carbon fibers 23a arranged in the same direction with a thermosetting insulating resin 23b. The carbon fiber plate 21 is formed by laminating three prepregs 23 such that a plurality of carbon fibers 23a are alternately arranged in different directions, and then curing the insulating resin 23b by pressure heating. That is, this carbon fiber plate 21 has a prepreg 23 in which the carbon fiber 23a is oriented in the other direction orthogonal to the aforementioned one direction between two prepregs 23 in which the carbon fiber 23a is oriented in one direction. It has an integrated structure with a sheet.

  The structure of a carbon fiber board can employ | adopt the thing of various structures. For example, it is a matter of course that the carbon fiber plate may be integrally formed with a carbon fiber mixed resin in which carbon fiber chips are randomly mixed so as to obtain conductivity. In addition, a woven fabric or nonwoven fabric is made using a large number of carbon fibers, and a prepreg is made by impregnating the woven fabric or nonwoven fabric with a thermosetting insulating resin to make thermosetting of one or more prepregs. You may make it make a carbon fiber board using the carbon fiber sheet which heat-cured resin. When using a plurality of prepregs, a plurality of prepregs using a woven fabric or a nonwoven fabric may be stacked, or a plurality of prepregs using a woven fabric and a prepreg using a nonwoven fabric may be mixed and stacked. Further, the carbon fiber plate may be formed by sandwiching one or more prepregs of woven or non-woven fabric between two prepregs made of only resin.

  Next, as shown in FIG. 5, a large carbon fiber plate 21 is cut by dicing using a dicing 25, and as shown in FIG. 6, a plurality of contact forming plates having the same shape and having a rectangular shape. 27 was manufactured (first step). The dicing 25 has a disc-shaped dicing blade 25a in which diamond abrasive grains are embedded in a binder made of resin bond, metal bond, etc., and carbon is obtained by rotating the dicing blade 25a in the direction of arrow A1. The fiberboard 21 is cut. In this example, after the carbon fiber plate 21 is brought close to the dicing 25 in the direction indicated by the arrow A2 and the carbon fiber plate 21 is cut into a strip shape, the strip-like carbon fiber plate 21 is further cut in a direction perpendicular to the longitudinal direction. A plurality of contactor-forming plate members 27 were formed.

  Next, as shown in FIG. 7, a plurality of contactor-forming plate members 27 were stacked in the thickness direction of the contactor-forming plate member 27 to form a rectangular parallelepiped laminate 29 (second step). And the laminated body 29 was arrange | positioned in the laminated body holder 31. FIG. The laminate holder 31 holds the laminate 29 so that dicing can be performed in a state where the laminate 29 is pressurized in the lamination direction. Then, as shown in FIGS. 7 and 8, dicing was performed on the laminate 29 using the dicing 33. The dicing 33 has one central slit forming dicing blade 33a and two side slit forming dicing blades 33b and 33c located on both sides of the central slit forming dicing blade 33a. The dicing 33 forms a slit by rotating the dicing blades 33a, 33b and 33c in the direction of the arrow A3. In this example, the laminated body 29 was brought close to the dicing 33 in the direction indicated by the arrow A4, and the laminated body 29 was diced. Then, as shown in FIG. 9, a central slit 35A was formed by a central slit forming dicing blade 33a. Further, the side slit forming dicing blades 33b and 33c formed the side slit portions 35B and 35C simultaneously with the central slit 35A (third step). The central slit 35A and the side slit portions 35B and 35C both open to one stacked surface of the stacked body 29, and extend in the stacking direction of the stacked body 29 and open to both side surfaces of the stacked body 29 in the stacking direction. ing.

  Next, through-holes 3a used for attachment to the holder 9 were collectively formed in the laminated body 29 by machining with a drill.

  Next, the contact forming plate material 27 was separated from the laminated body 29 after the dicing process to obtain a plurality of contacts 1 (fourth step). Accordingly, the portion where the central slit 35A is formed becomes the central slit portion 7A of the contact 1, and the portion where the side slit portions 35B and 35C are formed becomes the side slit portions 7B and 7C of the contact 1.

  Next, as shown in FIG. 10, the contact 1 was held by the contact holder 37. The contact holder 37 holds the contact 1 so that it can be chamfered. Then, chamfering was performed on a corner portion between the tip surface 5b and the side surface 5c by dicing using the dicing 37. The dicing 37 has one dicing blade 37a. The side surface 37b of the dicing blade 37a is inclined as it goes from one surface of the dicing blade 37a to the other surface. The chamfering was performed by bringing the side surface 37b of the dicing 37 into contact with the corner between the tip surface 5b and the side surface 5c. Such chamfering may be performed as necessary, and can be used as a contact without performing chamfering. Thus, the contact 1 shown in FIG. 1 was completed.

  According to the manufacturing method of this example, the slits are formed in the laminated body 29 of the plurality of contact forming plate members 27 by dicing, so that no burrs are generated in the laminated body 29 of the large number of contact forming plate members 27. , Slits can be formed collectively. Therefore, slits can be easily formed in a large number of contact forming plate materials 27 in a short time without providing a step of removing the burrs and finishing the surface.

  In the above example, an example in which a plurality of slits are formed has been described. However, the present invention can also be applied to a method of manufacturing the contact 101 having one slit 107 as shown in FIG. In this case, dicing processing may be performed using dicing having one dicing blade.

  Moreover, although the example of the contactor attached to the holder using the through-hole 3a was shown in the above example, as shown in FIGS. The present invention can also be applied to a method for manufacturing the contacts 201 and 301. In this case, the recesses 203a and 303a may be collectively formed on the laminate by various machining processes including dicing.

  In the above example, the side surface 37b orthogonal to the thickness direction of the dicing blade 37a is chamfered using the dicing blade 37a that is inclined from one surface of the dicing blade 37a toward the other surface. As shown in FIG. 13 and FIG. 14, chamfering is performed using a dicing blade 137 a having a groove 137 c that opens in the radial outer side of the dicing blade 137 a and one direction in the thickness direction at the edge of the dicing blade 137 a. You can also. The corner of the groove 137c has an R shape, and chamfering along the R shape of the groove 137c is performed on the corner 105d between the tip surface 105b and the side surface 105c of the contact 101.

  In the above example, the chamfering process is performed after the contactor forming plate 27 is separated from the laminate 29 to obtain the plurality of contacts 1 (after the fourth step), but the same shape is obtained by the dicing process. The carbon fiber plate may be cut and chamfered at the same time using a dicing blade having an R shape when manufacturing a plurality of contactor forming plate materials (in the first step).

It is a top view of the contact for variable resistors manufactured by the method of one embodiment of the present invention. It is a side view of the variable resistor which attached the contact shown in FIG. It is a top view of the carbon fiber board used with the manufacturing method of one embodiment of the present invention. It is sectional drawing of the carbon fiber board shown in FIG. It is a figure for demonstrating the form which cut | disconnects a carbon fiber board by a dicing process in the manufacturing method of one embodiment of this invention. It is a top view of the several board | plate material for contactor formation formed in the manufacturing method of one embodiment of this invention. It is a figure for demonstrating the form which forms a slit in a laminated body by a dicing process in the manufacturing method of one embodiment of this invention. It is a figure for demonstrating the form which forms a slit in a laminated body by a dicing process in the manufacturing method of one embodiment of this invention. It is a perspective view of the laminated body in which the slit was formed in the manufacturing method of one embodiment of this invention. It is a figure for demonstrating the form which chamfers to the corner | angular part between the front end surface and side surface of a contactor in the manufacturing method of one embodiment of this invention. It is a top view of the contact for variable resistors manufactured by the method of other embodiments of the present invention. (A) And (B) is a top view of the contact for variable resistors manufactured with the method of further another embodiment of this invention. It is a figure for demonstrating the form which chamfers to the corner | angular part between the front end surface and side surface of a contactor in the manufacturing method of other embodiment of this invention. It is the elements on larger scale of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Contact 3a Through-hole 7A Central slit part 7B, 7C Side slit part 21 Carbon fiber board 27 Contact formation board | plate material 29 Laminate 33 Dicing 35A Central slit 35B, 35C Side slit part 33a Central slit formation dicing blade 33b 33c Dicing blade for forming side slits

Claims (7)

A first step of preparing a plurality of contact-forming plate members having the same shape formed from a carbon fiber plate having conductivity formed in a plate shape using carbon fiber and a synthetic resin as main raw materials;
A second step of laminating the plurality of contactor-forming plate members in the thickness direction of the contactor-forming plate member to form a laminate;
A third dicing process is provided to form one or more slits that open in one stacking surface of the stack and extend in the stacking direction of the stack and open on both side surfaces of the stack in the stacking direction. Steps,
A variable resistor contact manufacturing method comprising: a fourth step of obtaining the variable resistor contact by separating the contact forming plate from the laminated body after the dicing. 2. The method for manufacturing a contact for a variable resistor according to claim 1, wherein, in the third step, a plurality of slits arranged in parallel at the same time are formed in the laminated body using a plurality of dicing blades. . 2. The variable resistor contact manufacturing method according to claim 1, wherein in the first step, the plurality of contact forming plate members are formed from the carbon fiber plate by dicing. 3. The contactor-forming plate material prepared in the first step has a rectangular outline.
The method for manufacturing a contact for a variable resistor according to claim 1, wherein the stacked body formed in the second step has a cubic shape or a rectangular parallelepiped shape. The mechanical processing for collectively forming through holes or recesses used for attachment is performed on the laminated body before or after the third step. Of manufacturing a contact for a variable resistor. In the fourth step, after the contact forming plate is separated from the laminate, the contact portion that contacts the sliding resistor of the variable resistor of the contact forming plate is chamfered by dicing. The manufacturing method of the contact for variable resistors of Claim 1 characterized by these. The contact for variable resistors manufactured by the method of any one of Claims 1 thru | or 6.

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