JPS644323B2 - - Google Patents

Description

[Detailed description of the invention]

INDUSTRIAL APPLICATION FIELD The present invention relates to a method of manufacturing a slider used in a variable resistor. Prior Art As a slider for a variable resistor, a slider in which a brush part that slides on a resistor and a slider body that supports both ends of the brush part are integrally formed by an elastic direction plate is widely used. It is being FIG. 1 shows an example of a conventional slider 1 of this type, in which 2 is a semicircular brush portion having a sliding contact portion 2a in the center that slides on a resistor, and 3 is a semicircular brush portion. From the current collecting part 3a formed in a substantially dish shape to the plate-shaped brush support parts 3b, 3b
The brush portion 2 is supported by the slider main body 3 with both ends thereof being continuous with the brush support portions 3b, 3b. An arc-shaped slit 4 extending along the circumferential direction is formed in the center of the width direction of the brush part 2, and the slit 4 allows the brush part 2 to move between the two sliding pieces 2A and 2B.
It is divided into Dish-shaped current collector part 3 of slider body 3
A hole 3c is formed in the center of a, and the slider 1 is rotatably supported on the substrate of the variable resistor using this hole. The slider 1 is formed by pressing a metal plate having elasticity and good conductivity, such as a phosphor bronze plate, a nickel silver plate, a beryllium plate, a copper plate, or a stainless thin steel plate. It is formed into a shape curved toward the substrate so as to have the necessary springiness to press the sliding contact portion 2a into contact with the resistor while the current collecting portion 3a is supported on the substrate of the variable resistor. In a variable resistor using this type of slider, the greater the number of sliding contacts, the lower the contact resistance and sliding noise, and the more stable the quality against changes in the surrounding environment. can be achieved. However, in the conventional slider, a slit 4 is formed in the brush part 2, and the brush part 2 is connected to a plurality of sliding pieces 2.
Since it was divided into A and 2B, the number of sliding pieces could not be increased, and therefore the number of sliding contacts could not be increased. In this conventional slider, if the number of slits is increased, it is possible to have multiple contacts, but if the number of slits is increased, the width of the brush portion 2 becomes wider, and accordingly, the width of the resistor must also be made wider. It is too harsh and impractical. Especially recently, there is a trend toward smaller variable resistors.
It is necessary to avoid increasing the size of the slider. OBJECTS OF THE INVENTION An object of the present invention is to provide a method for manufacturing a slider for a variable resistor that allows multiple contacts to be made without increasing the width of the brush portion. Structure of the Invention The present invention includes a brush part having a sliding contact part that slides on a resistor, and a slider main body that supports both ends of the brush part, which are formed by molding a conductive metal plate having spring properties. The present invention is a method for manufacturing a slider for a variable resistor that is integrally provided, and the present invention provides a method for manufacturing a slider for a variable resistor that is provided integrally with the metal plate by hitting one surface of the portion forming the brush portion of the metal plate on the resistor side with a press die. A surface punching step of forming a plurality of grooves having a V-shaped cross section extending parallel to each other in the length direction of the brush portion, and cutting a portion along each of the grooves on one surface of the portion where the brush portion is to be formed in the thickness direction. a cutting step of forming a linear cut portion and dividing the portion forming the brush portion into a plurality of sliding pieces extending close to each other in parallel; and a cutting step of forming a portion forming the brush portion. A deburring step is performed in which burrs generated in the cutting step are removed by polishing. According to each of the above methods, since a plurality of sliding pieces are formed by cutting without forming slits,
A large number of sliding pieces can be formed without increasing the width of the brush part. Further, since a burr removal process is performed to remove burrs generated in the cutting process, the displacement of each sliding piece is not hindered by burrs. Therefore, each sliding piece can be made to slide following the fine irregularities on the surface of the resistor, and the characteristics of the variable resistor can be improved. In particular, as in the method of the present invention, when a groove is formed on one surface of the portion where the brush portion is to be formed by performing a surface punching step and then a linear cut portion is formed, the contact point that contacts the resistor of each sliding piece Since chamfered portions are formed at both ends in the width direction, the influence of cutting burrs can be completely eliminated. Embodiments Examples of the present invention will be described below with reference to the accompanying drawings. FIG. 2 shows a slider 11 manufactured by the method of the present invention, which includes a substantially semicircular brush portion 12 and a slider body that supports both ends of the brush portion 12. It consists of 13. The slider main body 13 includes a current collecting portion 13a formed into a substantially dish shape and a current collecting portion 13a.
Brush holding parts 13b, 13 symmetrically projecting from the
A hole 13c is provided at the center of the bottom of the current collecting portion 13a, into which a support member or shaft is fitted when the slider is attached to the substrate of the variable resistor. Note that the hole 13c is not necessarily limited to a circular shape, and can be formed in any appropriate shape depending on the shape of the support member to be fitted into the hole. On the rear end side of the brush holding parts 13b, 13b,
When this slider is connected to an adjustment knob, a notch 13d into which a protrusion provided on the knob is fitted
is formed. The brush portion 12 is provided so that both ends thereof are continuous with the brush holding portions 13b, 13b, and the brush portion 12 and the current collecting portion 13a are separated by an arcuate slit 14. In the present invention, the brush portion 12 extends parallel to each other in close proximity to each other by a large number of linear cut portions 15, 15, . It is divided into a large number of arcuate sliding pieces 12A, 12B, 12C... Here, the linear cut section means a cut section obtained by cutting the brush section in the thickness direction with a cutter having a thin blade, and it is a cut section obtained by cutting the brush section in the thickness direction with a cutter having a thin blade. means a notch that does not have a line and can be substantially considered as a line. That is, in the present invention, the sliding pieces 12A, 12B, . In this manner, by dividing the brush portion into sliding pieces by the linear cut portions without providing slits, the number of sliding pieces can be increased without increasing the width of the brush portion. When the brush part is divided into sliding pieces by slits as in the past, it is difficult to increase the number of sliding pieces to three or more, but according to the present invention, the width of the brush part can be kept the same as before. It is possible to form five or more sliding pieces. Sliding pieces 12A, 12 constituting the brush portion 12
As shown in FIG. 3, a contact portion 12a that contacts the resistor 17 provided on the substrate 16 of the variable resistor is formed at the center of B, .
The contact 12a is formed into a shape curved toward the resistor 17 so as to have spring properties to press the contact 12a against the resistor 17. As described above, in the present invention, the brush portion is divided into a large number of sliding pieces by the linear cut portions, and each sliding piece is provided with a contact portion, so that the slider can have multiple contact points. , the characteristics of the variable resistor can be improved. Referring to FIGS. 4 and 5, an example of a variable resistor constructed using the slider 10 of the above embodiment is shown. In these figures, 16 is an insulating substrate, 17 is a resistor formed on the surface of the substrate 16,
18, 18 are terminal electrode parts connected to both ends of the resistor 17, and the resistor 17 and the terminal electrode parts 18,
18 is formed by printing or the like. A hole 16a is formed approximately in the center of the substrate 16, and a tubular portion 19a integrally formed with the terminal plate 19 that is in contact with the back surface of the substrate 16 is fitted into the hole 16a. A terminal portion 19b bent at right angles on the side opposite to the board 16 is formed at one end of the terminal plate 19, and a terminal portion 19b bent at a right angle on the opposite side to the board 16 is formed at the other end.
A bent locking protrusion 19c is formed on the 6 side. The locking protrusion 19c is connected to the hole 1 provided in the substrate 16.
6b, and the rotation of the terminal plate 19 is prevented by the engagement between the locking protrusion 19c and the hole 16b. The slider 10 connects its dish-shaped current collector 13a to the substrate 1.
6 and is placed on the surface side of the substrate 16 with the contact portions 12a, 12a, . ing. Then, the tip of the tubular portion 19a is caulked to the bottom side of the dish-shaped current collecting portion 13a over the entire circumference, and thereby the slider 10 is attached to the tubular portion 19.
The slider 1 is rotatably supported by a.
0 is electrically connected to the terminal board 19. Further, holes 16c, 16c are formed through the terminal electrode parts 18, 18 and the substrate 16, and eyelet parts 20a,
20a are fitted into these holes from the front side of the substrate 16. Then, the tips of the eyelet portions 20a, 20a protruding from the back side of the board 16 are caulked around the opening end of the hole 16c, whereby the terminal fitting 2
0 and 20 are attached to the substrate 16 and electrically connected to the terminal electrode section 18. As is clear from FIG. 5, the slider 10 of this embodiment has a large number of contacts 12a sliding on the resistor 17, so that it is possible to reduce contact resistance and sliding noise. It is possible to improve the characteristics of the variable resistor. The variable resistor shown in FIG. 5 can be attached with an operating knob 21 as shown by the chain line in the same figure, for example. This operation knob 21 is connected to the terminal board 19.
A shaft portion 21a that rotatably and removably fits into the inner periphery of the tubular portion 19a, a cover portion 21b that covers the slider 10 and the resistor 17, and a cover portion 21b.
The cover part 21b has an integral knob part 21c projecting from the upper surface thereof, and a protrusion 21d which fits into the notch part 13d of the slider 10 is provided on the lower surface of the cover part 21b. Further, a driver slot 21e is formed at the upper end of the knob portion 21c. In this example, it is of course possible to prevent the shaft portion 21a from coming off by caulking the lower end of the shaft portion 21a. In the above embodiment, a single resistor 17 is formed on the substrate 16, but a large number of variable resistor resistors may be formed on the printed circuit board, and a sliding resistor that slides over each resistor may be formed on the printed circuit board. By supporting the slider directly on a printed circuit board, the slider can also be manufactured by the method of the invention when a large number of variable resistors are constructed on a common substrate. In this case, it is particularly required to downsize the slider, so the width of the brush portion of the slider is approximately 1.0 mm. When dividing the brush part into sliding pieces using slits as in the past, the limit was to form two sliding pieces with a width of 0.35 mm by providing a slit with a width of 0.3 mm, but with the present invention. In this case, five or more sliding pieces can be easily formed. In the above embodiment, a rotary type slider was taken as an example, but the present invention can be similarly applied to a linear displacement type slider. 6 to 8 show an example of a variable resistor using a linear displacement type slider, and in these figures, 22 is an insulating substrate;
Reference numerals 3 and 24 denote a strip-shaped resistor and a conductive portion, respectively, which are formed in parallel by printing on the surface of the substrate 22. Terminal electrodes 25 and 26 made of conductive films are overlaid and connected to both ends of the resistor 23, and terminal portions 27 and 27' are formed at both ends of the conductive portion 24. The slider 31 used in this variable resistor has a slider main body 3
2 and the resistor 23 and the conductive part 24, first and second brush parts 33 and 34 are provided in parallel at the same interval and are supported at both ends by the slider body 32. The sliding body 32 consists of a substantially rectangular plate-shaped base 32a, and bent portions 3 bent from both ends of the base 32a in a direction perpendicular to the plate surface of the base.
2b, 32b and these bent parts 32b, 32
The locking arms 32a, 32c, . It is bent into. The brush parts 33 and 34 are formed by making cuts in the base 32a of the slider main body 32.
3 and 34, a large number (6 in this example) of sliding pieces 33A to 3 are formed by linear cut portions 35 parallel to each other.
It is divided into 3F and 34A to 34F. Brush part 3
3 and 34 are formed into a substantially doglegged shape convex to the substrate 22 side, and a sliding contact portion 33a is provided at approximately the center of each of the sliding pieces 33A to 33F and 34A to 34F that constitute both brush portions. and 34a are formed. As shown in Fig. 8, this slider 3
1 holds the substrate 22 between the brush parts 33 and 34 and the tip of each locking arm 32c.
2, and the sliding contact portions 33a and 34a of the brush portions 33 and 34 are respectively fitted to the resistor 2.
3 and the conductive part 24 while sliding. Next, a method for manufacturing a slider according to the present invention will be explained. FIG. 9 shows an example of the manufacturing process of the slider of the present invention, and this example shows the case of manufacturing a rotary type slider as shown in FIG. In manufacturing the slider of the present invention, first, as shown in FIG. 9A, a metal plate 40 made of an elastic and highly conductive material is prepared.
First, as shown in FIG. 9B, the current collector 13a of the slider body is molded, and then, as shown in FIG. 9C, holes 13c are formed in the bottom of the current collector 13a. Next, the 9th
As shown in Figure D and Figure 11A, the brush section 1
By striking one surface of the resistor side of the portion 12', which will become 2, with a press die, grooves 41, 4 with a V-shaped cross section extending parallel to each other in the length direction of the brush portion 12 are formed.
A surface punching process is performed to form 1, . . . . These grooves 41, 41, . Set it approximately equal to the length of . Note that the intervals between the grooves 41, 41, ... are very narrow, so due to the structure of the mold of the press processing machine, these grooves are
It is difficult to form with multiple presses. Therefore, the grooves 41, 41, .
For example, the grooves are formed one by one starting from the inner groove 41. After forming the grooves 41, 41, . . . by the above-mentioned surface punching process, as shown in FIG. Each groove 4 except groove 41
A cutting process is performed in which the portion corresponding to 1 is cut in the plate thickness direction from the surface opposite to the groove 41 with a cutting blade,
As shown in FIG. 10E, linear cut portions 15, 1
5, form... These linear cut portions 15,1
5, . . . are also formed one by one, starting from the inner linear cut portion 15, because the distance between them is very narrow. After this cutting process is completed, FIG.
As shown in FIGS. 10 and 11B, the outer contour of the slider is cut out to form a blank slider 11'. In this case, a frame part 42 is formed by leaving the end of the metal plate 40 in a band shape, and the blank part 11' is connected to the frame part 42 via a connecting part 43.
are connected. In the cutting step, a cutting burr 44 is generated, and this cutting burr 44 is located within the V-shaped groove 41. If this cut burr is left, it will not only damage the surface of the resistor, but also damage the sliding pieces 12A, 1.
2B, because it will prevent the free displacement of...
This may cause deterioration of the characteristics of the variable resistor. Therefore, in the method of the present invention, this cutting burr 4
A deburring process is performed to remove 4. This deburring step is performed, for example, by polishing the cut burr portion of the brush portion 12 with a rotating wire brush. As described above, if the V-shaped groove 41 is formed in advance by performing the surface punching process, the cross section of each sliding piece finished through the deburring process will be as shown in FIG. 11C. It becomes easy to form a shape that does not have sharp corners. Furthermore, even if a portion of the cut burr remains in the deburring process, since the cut burr remains within the groove 41, it is possible to prevent the cut burr from having an adverse effect on the surface of the resistor. After performing the deburring process as described above, the ninth
As shown in FIG. G, the brush portion 12 is formed into a curved shape, and a contact portion 12a is formed in the center thereof. The above-mentioned series of steps are performed sequentially by intermittently feeding the metal plate to a processing position where processing tools for performing each step are arranged, and sequentially with a large number of sliders connected to the frame section 42 by the connecting section 43. Manufacture.
Each slider 11 manufactured in this manner is separated from the frame portion 42 and attached to the substrate of the variable resistor when assembling the variable resistor. Furthermore, in the above embodiment, the brush part is curved and the contact part is formed after the deburring process, but the burr is removed after the brush part is first bent and the contact part is formed. The process may also be performed. In the above explanation, we have taken as an example the case where a rotary type slider as shown in FIG. 2 is manufactured, but the slider 31 used in the variable resistor shown in FIGS. It can be manufactured by the same method as . In order to confirm the effect of the present invention, the width of the brush part was
1.0 mm, and by forming four linear notches at intervals of 0.2 mm to form five sliding pieces, a slider with the structure shown in Fig. 2 was manufactured using a nickel silver plate.
By forming a carbon film resistor on a 96% alumina insulating substrate and attaching a slider to the substrate, the fifth
A variable resistor with the structure shown in the figure was assembled. In addition, as a conventional example, there is a first plate in which two sliding pieces with a width of 0.35 mm are formed through a slit of 0.3 mm in a brush portion with a width of 1.0 mm.
A variable resistor as a conventional example was assembled by using a slider having the structure shown in the figure and attaching it to the same substrate as above. When the sliding noise, humidity resistance load life, load life characteristics, and rotation life characteristics of these variable resistors were measured according to the JIS measurement method, the results shown in the table below were obtained.

[Table] From the above results, the use of the slider of the present invention can significantly improve the characteristics of a variable resistor compared to the case of using a conventional slider, and the effect of the present invention is significant. It turns out that there is something. The reason why the characteristics are improved by increasing the number of sliding pieces as in the present invention is that the contact area between the sliding element and the resistor increases, and because there are many sliding pieces, for example, the outer one Even if the contact portion of a single sliding piece falls off from the resistor, it has little effect on the contact resistance, misalignment of the printing on the resistor does not pose much of a problem, and many sliding pieces move up and down independently. This is thought to be due to the fact that the contact resistance can be kept uniform by suppressing the influence of the surface condition of the resistor over the entire movement range of the slider because it slides by following the minute irregularities on the surface of the resistor. It will be done. Effects of the Invention As described above, according to the present invention, by forming mutually parallel linear cut portions in the brush portion of the slider, the brush portion is divided into a plurality of sliding pieces. Compared to conventional sliders, which have slits in the brush section to form sliding pieces, the number of sliding contacts can be greatly increased, contributing to improved characteristics of variable resistors. There are advantages to being able to do so. In particular, as in the method of the present invention, when a groove is formed on one surface of the portion where the brush portion is to be formed by performing a surface punching step and then a linear cut portion is formed, the contact point that contacts the resistor of each sliding piece Chamfered portions are formed at both ends in the width direction, and when a deburring process is performed thereafter, the cross section of each sliding piece easily becomes a shape without sharp corners.
Further, even if a portion of the cut burr remains in the deburring process, the cut burr is formed within the groove, so that the remaining cut burr can be prevented from having an adverse effect on the surface of the resistor.

[Brief explanation of drawings]

Fig. 1 is a plan view showing a conventional example, Fig. 2 is a plan view showing an embodiment of the slider manufactured by the method of the present invention, and Fig. 3 shows the shape of the brush portion of the embodiment shown in Fig. 2. FIG. 4 is a plan view showing an example of a variable resistor constructed using the slider shown in FIG. 2, and FIG.
The figure is an enlarged cross-sectional view taken along the line -- in FIG. 8 is a sectional view taken along the line - in FIG. 7, FIGS. 9A to G are cross sections illustrating the finishing process of the sliding piece of the slider of the present invention, and FIG. 10 is a top view of FIG. 9F. FIGS. 11A to 11C are cross-sectional views sequentially showing the steps of forming a sliding piece in the method of the present invention. 11...Slider, 12...Brush portion, 12A-1
2E...Sliding piece, 12a...Sliding contact portion, 13...
...Slider body, 13a... Current collector, 13c...
Hole, 31... Slider, 32... Slider body, 3
3, 34... Brush section, 33A~33E, 34A~
34E...Sliding piece, 33a, 34a...Sliding contact.

Claims (1)

[Scope of Claims] 1 A conductive metal plate having spring properties is formed to form a brush portion having a sliding contact portion that slides on a resistor, and a slider body that supports both ends of the brush portion. In the method of manufacturing an integrally provided slider for a variable resistor, one surface of the portion forming the brush portion of the metal plate on the resistor side is struck with a press mold, thereby forming a shape in the length direction of the brush portion on the one surface. a surface punching step of forming a plurality of grooves having a V-shaped cross section extending parallel to each other; and a linear cut portion is formed by cutting a portion along each of the grooves on one surface of the portion where the brush portion is to be formed in the thickness direction of the plate. a cutting step in which the portion forming the brush portion is divided into a plurality of sliding pieces extending close to each other in parallel using the linear cut portion; and by polishing the portion forming the brush portion. A method for manufacturing a slider for a variable resistor, comprising a deburring step for removing burrs generated in the cutting step.