JPH0682566B2 - Slider and variable resistor equipped with the slider - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a slider, for example, a slider for sliding on a resistor of a variable resistor to adjust a resistance value and the slider. A variable resistor provided.

2. Description of the Related Art Conventionally, the slider shown in FIG. 19 has been used as a slider used in a variable resistor or the like. This one is
An arm portion 51 having a notch 52 is formed in the peripheral portion of a disk-shaped substrate portion 51, the arm portion 51 is bent at both end portions 51a, 51a, and the central portion is projected to form contact portions 51b, 51b. is there. The notch 52 is for dividing the contact points 51b, 51b into two to improve contact reliability.

However, in this slider, as shown in FIG. 20, the contact points 51b, 51b are in the positions shown by the solid line in the free state, but by the two-dot chain line in the state of being pressed against the resistor. It is in the position shown. That is, in this slider, the contact portion 51
The positions of b and 51b deviate in the radial direction of the slider indicated by arrow D depending on the state.

By the way, it means that the positions of the contact points 51b, 51b of the slider are displaced inward in the radial direction of the slider as compared with the state in which the contact points 51b, 51b in the free state are pressed against the resistor substrate. ,
This means that it is difficult to insert mold the slider on the rotor. Because the insert molding of the slider to the rotor is free,
51b, 51b are housed in the space of the mold,
This is because if the contact portions 51b, 51b are displaced inward in the radial direction of the slider, a portion that must be a thin portion will be formed in the die, which is unsuitable for die processing and die life. Further, in this structure, the contact parts 51b, 51b divided into two points are in contact with each other adjacent to each other, and mutual movement of the contact parts 51b, 51b causes a problem that a movement following the resistor is restricted. Have Further, there is a big problem that there is a limit to miniaturization of the slider itself due to its structure.

Therefore, as shown in FIG. 21, the central portion of the arm 51 is straight line M.
It is conceivable that the arm portion 51 is divided into two in the circumferential direction by simply cutting with, and the cut end portion is further bent to form the contact portions 51b and 51b. In this case, the cut line M is inclined with respect to the straight line A passing through the center of the substrate portion 50. However, this slider has a problem that the contact portions 51b, 51b have a small width dimension, are difficult to process, and are difficult to be miniaturized.

Further, as shown in FIG. 22, it is conceivable to cut the central portion of the arm portion 51 by a straight line N to form the contact portions 51b, 51b. In this case, the cut line N is orthogonal to the straight line A. With this slider, the contact portions 51b, 51b can have a large width, but as in the case of FIG. 19, no gap is formed between the contact portions 51b, 51b, and mutual interference occurs between the contact portions 51b, 51b. It will be.

Furthermore, the ones shown in FIGS. 21 and 22 are both arm parts.
Since 51, 51 are bent at the bent portions 51a, 51a along the straight line A'passing through the center of the substrate portion 50, the contact portions 51b, 51b are in the free state and the pressed state as in the case of FIG. As a result, it moves in the horizontal direction with respect to the substrate portion 50, and it is difficult to insert mold the rotor.

Therefore, the slider according to the present invention has a shape in which the contact portion includes at least one substantially arc shape, for example, a shape in which two arc shapes are combined, or a straight line and at least one substantially shape. It is divided into an inner peripheral part and an outer peripheral part by a combination of arc shapes, and the arm part is bent in parallel with a straight line connecting the center of the board part and the contact part, while the contact part is formed at the tip in the substantially central part of the board part. It is characterized in that the other arm portion having is projected.

The variable resistor according to the present invention includes the slider. That is, the substrate portion of the slider is insert-molded on the rotor, and the rotor is rotatably attached to the substrate portion on the surface of which the collector electrode and the resistor are provided.
The contact portion located in the central portion is in contact with the collector electrode, and the contact portion in the peripheral portion is in contact with the resistor.

In the above configuration, a gap is formed between the divided contact portions located on the peripheral portion of the substrate portion, and mutual interference between the contact portions is prevented. Also, since the arm part is bent in parallel with the straight line connecting the center of the substrate part and the contact part, the contact part only moves vertically even if it is in contact with the resistor, and the diameter of the slider There is no positional deviation in the direction, and the contact part can be housed in the space of the mold during insert molding, and stable molding can be performed.

Embodiments Embodiments of a slider and a variable resistor according to the present invention will be described below with reference to the accompanying drawings.

As shown in FIGS. 12 and 13, the present variable resistor is a rotor in which a resistance substrate 1 with terminals having a resistor 6 is attached to a case 2 and a slider 4 is provided in the case 2. 3 is rotatably held, and from the case 2, lead terminals 9, 10
And the collector terminal 11 is drawn out.

As shown in FIG. 1, the substrate 1 has a resistor 6, electrodes 6a and 6b, a collector electrode 7 and an elastic body 8 formed on the surface thereof. The resistor 6 has a horseshoe shape, and the first end is provided with an electrode 6a at one end thereof.
The lead terminal 9 is the second lead terminal via the electrode 6b at the other end.
10 are connected by soldering. The collector electrode 7 extends from the central portion of the substrate 1 to one end portion of the substrate 1, and the collector terminal 11 is connected to the end portion.

By the way, the terminals 9, 10, 11 are made of copper alloy or the like, and the electrodes 6a, 6
For attachment to b, 7, at least the tip portions of the terminals 9, 10, 11 are preliminarily subjected to solder plating, the solder plated portions are brought into contact with the electrodes 6a, 6b, 7 and heated by Joule heat,
The plating layer is melted by heating with a heater or the like and soldered. In this case, it is preferable to use alumina for the substrate 1 and silver or silver-palladium alloy for the electrodes 6a, 6b and 7.

On the other hand, the elastic body 8 is annularly fixed to the surface of the substrate 1 at a position facing a skirt portion 3c of the rotor 3 described later. As a material of the elastic body 8, an insulating silicon elastomer or the like that withstands soldering temperature and withstands solvents such as flux cleaning is used. Further, as a method of fixing to the substrate 1, screen printing, drawing method, dipping or the like can be adopted. As a result, when slidingly contacting the rotor 3, it is possible to obtain the internal hermeticity and increase the torque to stabilize the torque. Also, the substrate 1 and the case 2
When they are integrated by insert molding, there is an advantage that a cushioning action is obtained, the problem that the substrate 1 is cracked is prevented, and the molding resin of the case 2 can be suppressed from flowing to the resistor 6 side. The elastic body 8 may be fixed to the lower surface of the skirt portion 3c of the rotor 3.

By the way, the case 2 including the substrate 1 is manufactured by being held by the hoop material 30 processed into the shape shown in FIG. That is, the board 1 is held by the terminals 9, 10, 11 and the dummy terminals 31, 31 which are soldered as described above, and in this state is insert-molded in the case 2 (see FIGS. 3 and 5). Finally, the tie bar of the hoop material 30, the dummy terminals 31, 31
Is cut. The lead terminals 9 and 10 have bifurcated branch terminals 9a, 9b, 10a, 1 by forming slits 9 ', 10' in the longitudinal direction.
It is divided into 0b. This is a standard 2.5mm described below
This is to correspond to the pitch and the mounting form of the irregular 2.5 mm pitch.

As shown in FIGS. 3 to 6, the case 2 has a cylindrical body that opens upward, and extends from the side surface to the bottom surface of the terminal.
A plurality of grooves 12a, 12b, 13a, 13b, 14 capable of holding 9, 10, 11 are formed. The cylindrical portion 2a opened upward has an inner diameter capable of rotatably accommodating the rotor 3, and a ring-shaped protrusion 2b having a width required for heating and bending is formed on the inner peripheral portion of the upper portion.

The grooves 12a, 12b, 13a, 13b, 14 are formed to match the widths of the lead terminals 9, 10 and the collector terminal 11, and the grooves 12a, 13a correspond to the branch terminals 9a, 10a of the lead terminals 9, 10, respectively. Groove 1 on branch terminals 9b, 10b
2b and 13b are supported. This groove extends from the top edge of the case 2 through the side surface to the bottom surface side so that each terminal 9, 10, 11 protruding from the side surface of the case 2 can be bent at a desired position on the side surface or the bottom surface and taken out to the outside. Has become. Further, the groove interval is set so as to match the distance between the insertion holes of the terminals formed on the printed circuit board or the like on which the variable resistor is mounted, that is, the pitch.
Both pitch and irregular 2.5mm pitch can be supported.

Further, the edges 12c, 13c, 14c of each groove are projected outward to facilitate the process of fixing each terminal 9, 10, 11, that is, heat fusion, etc., and the stability when mounted on a printed circuit board. It also has a stand-off effect to improve flux and flux and to improve soldering.

As a material of the case 2, it is preferable to use a thermoplastic resin having a heat distortion temperature equal to or lower than that of the rotor 3, such as PBT resin.

As shown in FIGS. 7 to 9, the rotor 3 has a cross-shaped driver groove 3a formed on the upper surface thereof, and an annular skirt portion 3c facing the elastic body 8 on the substrate 1 formed at the lower portion thereof. Has been done. Further, the substrate portion 4a of the slider 4 is integrally fixed to the lower portion by insert molding. Protrusions 3d, 3d
Are projected on the bottom surface side, and when the rotor 3 is rotated by a driver to adjust the resistance value, the rotor 3 is damaged by the applied pressure and the slider 4 is deformed by abutting on the substrate 1. Prevent from doing. As the material of the rotor 3, a thermosetting resin or a thermoplastic resin having excellent heat resistance, such as PPS resin, is used, so that the ring-shaped protrusion 2b of the case 2 is not deformed or deteriorated in characteristics by heat during bending. It can be prevented.

As shown in FIG. 10 and FIG. 11, the slider 4 is formed by pressing a single conductive metal plate, and has a substrate portion 4a.
And a contact portion 4d located at the tip of the arm portion 4c, and contact portions 4f, 4f located at the tip of the pair of arm portions 4e, 4e located at the peripheral portion. The substrate portion 4a is bent at the end portion 4b to have a double structure. The arms 4e, 4e extend in the circumferential direction, and
As is clear from the figure, the contact points 4f, 4f are cut into two parts, that is, an inner peripheral part and an outer peripheral part by cutting the contact parts 4f, 4f with a curved line formed by combining straight lines and arc shapes. Further, the arm portions 4e, 4e are connected by the straight lines B, B parallel to the straight line A connecting the center of the board portion 4a and the contact portions 4f, 4f.
Is bent toward the substrate 1 side, and the vicinity of the tip is bent in the opposite direction to form the contact portions 4f, 4f. In this case, the contact portions 4f, 4f are arranged in parallel on the straight line A when brought into contact with the resistor 6 and brought into an operating state after all bending work is completed.

By the way, the contact parts 4f, 4f are
It is located at the position indicated by the chain double-dashed line in the figures and FIG. 11, and when it is mounted on the substrate 1, it bends in the direction of arrow D and shifts to the position of the solid line.
That is, in this embodiment, the arm portion 4 is formed by the straight lines B and B parallel to the straight line A.
Since e and 4e are bent, the contact points 4f and 4f move vertically in the arrow D direction. If the arm portions 4e, 4e are bent at an angle with respect to the straight line A, when the contact portions 4f, 4f are present in the solid line position when mounted on the substrate 1,
In the free state, the contact points 4f, 4f must be displaced in the direction of arrow E from the position of the chain double-dashed line. The rotor 3 is molded by contacting the contact parts 4f, 4 in the space of the mold (not shown).
The f and the arms 4e, 4e are accommodated, but if the contact points 4f, 4f are free, the arrow E rather than the two-dot chain line position is used.
If they are displaced in the direction, contact points 4f, 4f and arm portions 4e, 4e,
4e cannot be stored in the space of the mold. That is, in this embodiment, the arm portions 4e, 4e are bent along the straight lines B, B parallel to the straight line A so that the contact portions 4f, 4f move vertically in the direction of the arrow D. Therefore, the rotor 3 is molded. Is possible.

Further, in this embodiment, since the contact portions 4f, 4f are divided by the curved line including the arc shape, when the arm portions 4e, 4e are bent along the straight line B, as shown in FIG. 9, a gap is formed between the contact portions 4f, 4f. G
Is formed, mutual interference between the contact portions 4f, 4f is prevented, and the resistors 6 follow the resistors 6 and can operate freely and the contact reliability is improved. Further, the contact portions 4f, 4f can have a large width dimension, and the processing accuracy is also improved.

The slider 4 configured as described above includes the rotor 3 on the case 2.
When assembled together, the contact portion 4d contacts the collector electrode 7, the contact portions 4f, 4f contact the resistor 6, and between the terminals 9, 11 and 10, 11 depending on the rotation angle of the rotor 3. The resistance value is adjusted.

Next, regarding the assembling of this variable resistor, FIG. 12 and FIG.
This will be described with reference to FIGS. First, the tie bars 40, 40 of the slider 4 are cut off and the single rotor 3 is housed in the cylindrical portion 2a of the case 2. Next, the ring-shaped protrusion 2b of the case 2 is bent by thermal crimping to prevent the rotor 3 from coming off. This bending process is performed by heat bonder, ultrasonic wave process, etc., and the rotor 3 is rotatably held in the case 2.

A part of the protrusion 2b is preliminarily formed to be high (indicated by reference numeral 2c in FIG. 5), and the protrusion 3b formed on the upper face of the rotor 3 contacts the upper face of the rotor 3 during the bending process. Thus, it functions as a stopper 2c that regulates the rotation angle of the rotor 3. A plurality of scales 15 are formed on the upper surface of the case 2 outside the ring-shaped protrusion 2b. The scale 15 is formed as a recess and is located close to the driver groove 3a of the rotor 3, and the driver groove 3a serves as an index and serves as a guide for the rotation angle of the rotor 3.

Then, when the tie bars of the terminals 9, 10 and 11 are cut off, the lead terminals 9 and 10 and the collector terminals protruding from the side surface of the case 2 are removed.
A variable resistor with 11 is obtained.

By the way, these lead terminals 9 and 10, collector terminal 11
Is a plurality of insertion holes formed in the printed circuit board, that is, a standard 2.5 mm pitch, along the groove provided in the case 2 and bent at a predetermined position to protrude outward.
It is also possible to adapt to both the irregular 2.5 mm pitch. On the printed circuit board 16, as shown in FIGS. 15 and 16,
A plurality of insertion holes 17 are formed at a pitch of X, and this X is usually set to 2.5 mm. What is the standard 2.5 mm pitch?
As shown by the chain double-dashed line in Fig. 15, the collector terminal 11 is inserted so that the base terminal 2X and the height X form an isosceles right triangle.
17a, the lead terminal 9 is inserted into the insertion hole 17b, and the lead terminal 10 is inserted into the insertion hole 17c. Anomaly 2.5
The mm pitch means that the collector terminal 11 is inserted in the insertion hole 17a and the lead terminal 9 is inserted in the insertion hole 17b so that an isosceles triangle having two sides of X is formed, as shown by a two-dot chain line in FIG. This is a mounting form in which the lead terminals 10 are inserted into the insertion holes 17c, respectively.

Then, the lead terminals 9 and 10 and the collector terminal 11 are
According to the above-mentioned two types of mounting forms, it is possible to take out not only from the side surface perpendicular to the driver groove 3a located on the upper surface of the case 2 shown in FIG. 17 but also from the bottom surface side of the case 2. .

In addition, when taking out from the side surface side, the case of adapting to the standard 2.5 mm pitch (see the two-dot chain line Y1 in FIG. 17) will be described. First, the collector terminal 11 protruding from the side surface of the case 2 is directed to the bottom surface side. Bend it along the groove 14. Then, it is bent again at a point P1, which is a predetermined position, and is projected in a direction perpendicular to the side surface. In the lead terminals 9 and 10, the branch terminals 9b and 10b are cut off, the remaining branch terminals 9a and 10a are bent toward the upper surface side, and are placed along the grooves 12a and 13a. Further, it is bent again at points P2 and P3, which are predetermined positions, and projected so as to be parallel to the collector terminal 11. By this, the take-out position of the isosceles right triangle having the collector terminal 11 as the apex can be determined.

Next, when adapting to the irregular 2.5 mm pitch (refer to the chain double-dashed line Y2 in FIG. 17), first the collector terminal 11 is bent toward the upper surface side of the case 2 and along the groove 14. Then, it is bent again at a point P4, which is a predetermined position, and is projected in a direction perpendicular to the side surface. Lead terminals 9 and 10 are branch terminals 9a and 1
0a is cut off, and the remaining branch terminals 9b and 10b are bent toward the bottom surface side and along the grooves 12b and 13b. Further, it is bent again at points P5 and P6, which are predetermined positions, and is projected in the same direction as the collector terminal 11. This makes it possible to determine the take-out position of the isosceles triangle having the collector terminal 11 as the apex.

On the other hand, when the terminals 9, 10 and 11 are taken out from the bottom side of the case 2, the terminals 9, 10 and 11 are arranged on the bottom surface of the case 2 according to the standard 2.5 mm pitch and the irregular 2.5 mm pitch as described above. 17th
It is sufficient to project the triangles Y1 and Y2 in the figure so as to form them. At the take-out position, as shown in FIG. 18, for example, in the case of the bottom side, if the edge portion of the groove 12a is heated and crushed to the side of the branch terminal 9a to form a caulked portion, the branch terminal 9a is fixed. It is prevented and the rise is prevented.

EFFECTS OF THE INVENTION As is apparent from the above description, according to the present invention, the contact portion is divided into the inner peripheral portion and the outer peripheral portion by the curve including at least one substantially arc shape, and the center of the substrate portion and the contact portion are separated. Since the arm portion is bent in parallel with the straight line connecting with, the slider itself can be downsized, and a gap is formed between the contact portions, so that mutual interference between the contact portions can be prevented and noise can be reduced. . Moreover, the contact portion only moves vertically when moving from the free state to the pressure contact state and does not move in the radial direction of the slider, and the contact portion and the arm portion are housed in the space of the mold. Since the slider can be insert-molded on the rotor, the number of assembling steps can be reduced. Also, by molding the slider with a hoop material, a continuous automatic assembly line can be constructed, and production efficiency is improved.

[Brief description of drawings]

1 to 18 show an embodiment of a variable resistor according to the present invention. FIG. 1 is a plan view of a resistance board with terminals, FIG. 2 is a plan view of terminals before assembly, and FIG. The substrate is insert-molded in a case in a half sectional plan view, FIG. 4 is a side view of FIG. 3, FIG. 5 is a sectional view taken along the line II of FIG. 3, and FIG. 6 is a bottom view of FIG. Fig. 7 is a plan view of a rotor insert-molded with a slider, Fig. 8 is a sectional view taken along the line II-II of Fig. 7, Fig. 9 is a bottom view of Fig. 7, Fig. 10, Fig. 11 Each of the figures is an explanatory view showing the bending of the contact portion of the slider, FIG. 12 is a half sectional plan view of the assembled variable resistor, FIG. 13 is a sectional view taken along the line III-III of FIG. 12, and FIG. Is a bottom view of FIG. 12, FIG. 15 is a plan view showing the standard pitch of the insertion holes formed in the printed circuit board, FIG. 16 is a plan view showing the irregular pitch of the insertion holes, and FIG.
The figure is a side view of the case showing the protruding positions of the terminals set to the standard pitch and the irregular pitch, and FIG. 18 is a perspective view showing the bent state of the terminals. FIG. 19 is a plan view of a slider used in a conventional variable resistor, and FIG. 20 is a front view thereof. 21st
FIG. 22 and FIG. 22 are plan views of the slider considered as the back surface of the present invention. 1 ... Resistor substrate, 2 ... Case, 3 ... Rotor, 4 ...
Slider, 4a ... substrate part, 4c, 4e ... arm part, 4d, 4f ... contact part, 6 ... resistor, 7 ... collector electrode.

Claims (2)

[Claims] 1. An arm portion provided on a peripheral portion of a substrate portion is divided into an inner peripheral portion and an outer peripheral portion by a curve including at least one substantially arcuate shape, and a tip of the arm portion serves as a contact portion, and a substrate is provided. A slider characterized in that while bending the arm portion in parallel with a straight line connecting the center of the contact portion and the contact portion, another arm portion having a contact portion at the tip is projected in the substantially central portion of the substrate portion. . 2. The substrate portion of the slider according to claim 1 is insert-molded on a rotor, and the rotor is rotatably attached to a substrate portion having a collector electrode and a resistor provided on the surface thereof, and A variable resistor characterized in that a contact portion is brought into contact with a collector electrode and a contact portion located at a peripheral portion is brought into contact with a resistor.