JP2002050505A - Variable resistor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inexpensive variable resistor, the insulating substrate of which will not crack and which has a small size and a low height, and to provide a method of manufacturing the resistor. SOLUTION: This variable resistor comprises the insulating substrate 1, which has a hollow hole 1a in its central part for housing a sliding body 4, has a resistor film 2 on its surface, and is provided with metallic terminals 3a and 3b electrically connected to both ends of the film 2; the sliding body 4 having a through-hole 4b at its center and a slider 4a which slides on the film 2 in a contacting state; and a sliding body holding plate 5, having a plate section 5c on which the sliding body 4 is placed in the rear-side opening of the hollow hole 1a of the substrate 1; a cylindrical section 5a which is caulked on the upper surface side of the sliding body 4 after passing through the through-hole 4b, a plurality of fixing sections 5d, 5e, and 5f which are extended from the plate section 5c to the surface of the substrate 1 via the side face of the substrate 1; and lead terminals 5b.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a variable resistor.

[0002]

2. Description of the Related Art A variable resistor is disclosed in, for example,
No. 4805 or JP-A-7-22215,
Widely known.

The schematic structure is as shown in FIGS. 5 to 7, reference numeral 101 denotes an insulating substrate.
a has a hollow hole 101a through which only a can pass. The planar shape of the insulating substrate 101 is such that protrusions 101b and 101c are formed on one end surface of the insulating substrate 101.
The insulating substrate 101 is formed of ceramic or the like.

On the surface of the insulating substrate 101, a resistor film 10 having a substantially horseshoe shape centered on the hollow hole 101a is provided.
2 are formed. Both ends of the resistor film 102 extend to the protrusions 101b and 101c, and the surface of the substrate,
Terminal electrode 103 formed over the side surface and the back surface
a, 103b.

On the resistor film 102 of the insulating substrate 101, a substantially dish-shaped sliding body is rotatably arranged. The sliding body is provided with a main body 104a and a slider 104c that makes sliding contact on the resistor film 102, and a through-hole 104b through which a caulking pin 105a is inserted is formed in the center portion. The sliding body 104 is formed of stainless steel or the like. Further, the sliding body 104 has a driver flat plate portion 111 having an adjustment groove 104d into which an adjustment driver that is folded back from the substantially dish-shaped main body portion 104a can be inserted.

On the back surface of the insulating substrate 101, a lead terminal 105 having a caulking pin 105a is arranged. The lead terminal 105 extends to the other end surface of the insulating substrate 101, and the cylindrical portion 105a
The front end portion extends upward to form a hollow hole 1 in the insulating substrate 101.
01a, caulking is performed in the main body 104a of the sliding body 104 so as to sandwich the flat plate portion 105c and the insulating substrate 101 through the through hole 104b of the sliding body 104.
Note that the lead portion 105b of the lead terminal 105 extending from the back surface of the insulating substrate 101 to the side surface on the other end surface side is subjected to a plating process such as solderable solder plating.

Thus, the sliding member 104 and the lead terminal 1
05 is electrically connected to the resistor film 102.
Between the resistor film 102 and the sliding body 10 between the terminal electrode 103a (103b) connected to both ends of the
Thus, a predetermined resistance component is obtained corresponding to the connection point with the fourth slider 104c.

In another variable resistor disclosed in Japanese Patent Application Laid-Open No. 7-22215, a variable resistor having a structure in which lead terminals are integrally formed with an insulating substrate is disclosed.

[0009]

However, in the above-mentioned conventional configuration, it is necessary to caulk the insulating substrate 101 between the flat plate portion 105c of the lead terminal 105 and the main body portion 104a of the sliding member 104. There was a problem that a crack and a crack of 101 were generated.

[0010] Further, since the insulating substrate 101 is interposed therebetween, the height of the variable resistor is limited to the insulating substrate 101 and the sliding member 1.
However, there is a problem that the height is increased and the height is increased.

Also, in the variable resistor disclosed in Japanese Patent Application Laid-Open No. 7-22215, since the lead terminals need to be formed integrally with the insulating substrate, there is a problem that the material of the insulating substrate is limited to resin or the like. Was. The present invention solves the above-mentioned conventional problems, and provides a small, low-profile, and inexpensive variable resistor that does not cause cracks or cracks in an insulating substrate, and a method of manufacturing the same.

[0012]

According to the present invention, a hollow hole for accommodating a sliding body is formed in a center portion, a substantially horseshoe-shaped resistor film is formed on the surface, and both ends of the resistor film are electrically connected to each other. An insulating substrate provided with a metal terminal connected to the substrate, a sliding body having a substantially dish-like shape having a through hole formed at the center thereof, and having a slider slidably in contact with the resistor film, and a hollow hole of the insulating substrate. A flat plate portion on which the sliding body is placed at the back surface opening, a lead terminal extending from the flat plate portion to the side surface of the insulating substrate, and a cylindrical portion that is inserted into the through hole and is caulked on the upper surface side of the sliding body. A sliding body holding plate having a plurality of fixing portions extending from the flat plate portion to the surface of the insulating substrate via the side surface of the insulating substrate.

According to the present invention, the sliding body is rotatably held by the sliding body holding plate disposed on the back side of the insulating substrate. That is, since the insulating substrate is not interposed in holding the sliding body, excessive stress concentration does not occur on the insulating substrate, and cracking of the insulating substrate can be prevented.
Further, the height of the variable resistor is substantially only the thickness of the sliding body, and the height of the variable resistor can be reduced.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a variable resistor according to the present invention will be described with reference to the drawings.

FIG. 1 is a plan view of a surface of a variable resistor according to the present invention.
FIG. 2 is a sectional view of the variable resistor of the present invention, and FIG. 3 is a rear plan view of the variable resistor of the present invention.

In FIG. 1, 1 is an insulating substrate, 2 is a resistor film, 3 is a metal terminal, 4 is a sliding body, and 5 is a sliding body holding plate.

The insulating substrate 1 is made of a ceramic or the like, and a hollow 1a is formed near the center of the insulating substrate 1 and extends through the insulating substrate 1 in the thickness direction.

A horseshoe-shaped resistor film 2 made of a metal oxide such as ruthenium oxide is formed on one main surface of the insulating substrate 1. At both ends of the resistor film 2, substantially U-shaped metal terminals 3 a and 3 b connected to the resistor film 2 and mounted on the outer peripheral portion of the insulating substrate 1 are formed. The metal terminals 3 a and 3 b are respectively formed so as to be electrically connected to at least the resistor film 2 and extend to the front surface, the side surface, and the rear surface of the insulating substrate 1.

A protrusion 1b is formed on an end surface of the insulating substrate 1 facing the metal terminals 3a and 3b. Further, the insulating substrate 1 extended at both ends of the resistor film 2
Is formed with a slip 1C through which some of the metal terminals 3a and 3b are inserted.

In the hollow hole 1 a of the insulating substrate 1, a substantially dish-shaped sliding member 4 that slides on the resistor film 2 is disposed. The sliding member 4 is made of a metal material such as stainless steel to which solder does not easily adhere. In addition, the sliding body 4
Can be inserted with a substantially dish-shaped main body 4a, a through hole 4b formed in the center of the main body 4a, a slider 4c that slides on the resistor film 2, and an adjustment driver. The driver flat plate portion 11 in which the adjustment groove 4d is formed is composed of:

On the back side of the insulating substrate 1, a sliding body holding plate 5 is arranged so as to close the back opening of the hollow hole 1a of the insulating substrate 1. The sliding member holding plate 5 has a flat plate portion 5c on which the sliding member 4 is placed, and a cylindrical portion 5a which is inserted into the through hole 4b of the sliding member 4 and is caulked on the upper surface side of the sliding member 4.
Lead terminals 5b extending from the flat plate portion 5c to the side surface of the insulating substrate 1, and a plurality of fixing portions 5d, 5d extending from the flat plate portion 5c to the surface of the insulating substrate 1 via the side surface of the insulating substrate 1.
e, 5f.

The lead terminals 5b extending from the back surface of the insulating substrate 1 to the side surface on the other end surface side are plated with solderable solder plating or the like.

The fixed portion 5 extending from the flat plate portion 5c
Reference numerals d, 5e, and 5f are bent at the front surface of the insulating substrate 1 from the back surface to the side surfaces.

The hollow portion of the cylindrical portion 5a is filled with a hollow closing member 19 such as a resin. This hollow part closing member 19 performs vacuum suction of the variable resistor from the upper surface side,
When the sheet is conveyed to a predetermined position, leakage of suction is prevented.

With the above-described structure, the sliding member 4 and the lead terminal 5b are electrically connected to each other, and between the metal terminals 3a and 3b connected to both ends of the resistor film 2 and the lead terminal 5b. A predetermined resistance component is obtained corresponding to the connection point between the resistor film 2 and the slider 4c of the sliding body 4.

According to such a structure, the sliding member 4 is directly mounted on the flat plate portion 5c of the sliding member holding plate 5 at the opening on the back surface side of the one hollow hole 1a of the insulating substrate, and is crimped. Therefore, the crimping process can be performed without imposing a load of the crimping process on the insulating substrate 1.

The fixing portions 5d, 5e, and 5f hold the sliding body holding plate 5 from different directions of the insulating substrate 1. The positioning of the substrate 1 is performed, and the rear caulking is formed. It is possible to suppress the occurrence of problems such as displacement when the moving body 4 is mounted or due to the influence of the slider 4c.

Further, the height of the variable resistor is substantially equal to the height of the sliding member 4, so that the height can be reduced.

Next, a method of manufacturing a variable resistor according to the present invention will be described with reference to FIGS. 6 is an exploded perspective view of the variable resistor of the present invention before assembly, FIG. 5 is a plan view of the lead frame of the present invention, and FIG. 7 is an exploded perspective view of the lead frame of the present invention before mounting the insulating substrate.

The lead frame 6 integrally formed with the flat plate portions 5c at appropriate intervals is conveyed along the pitch direction. During the conveyance, the cylindrical portion 5a is placed on the upper surface of the flat plate portion 5c. (See FIG. 6).

Next, the fixing portions 5d, 5e and 5f are bent so as to fix and hold the insulating substrate 1, respectively. (See FIG. 7).

Next, the main body 4a of the sliding body 4 is inserted into the hollow hole 1a of the insulating substrate 1, and the cylindrical portion 5a is passed through the through hole 4b.

Next, the tip of the cylindrical portion 5a is widened by caulking, and the sliding body 4 is rotatably held on the sliding body holding plate 5. Next, it is separated from the lead frame 6 and the assembly is completed.

The metal terminals 3a and 3b may be formed integrally with the lead frame, and a part of the metal terminal 3 may be inserted through the fixing slit 1c of the insulating substrate 1.

According to such a manufacturing method, the insulating substrate 1
When the sliding member 4 is mounted, the positioning of the substrate can be performed, and when the sliding member 4 is mounted later, it is possible to suppress the occurrence of troubles such as a positional shift due to the influence of the main body 4a and the slider 4c.

The fixing portions 5d, 5e and 5f are connected to the cylindrical portion 5
When the angle is set so that the upper side is opened with respect to a, the mounting of the insulating substrate 1 becomes easier. Furthermore, the convex portion 1b
However, the holding terminals 5d and 5e restrict the mounting, so that accurate mounting of the insulating substrate 1 is facilitated.

Further, since the mounting of the insulating substrate 1 and the mounting of the sliding body 4 can all be performed on the lead frame 6, the production efficiency is greatly improved.

The inventor examined the height dimension (T dimension) of the variable resistor of the present invention and the conventional variable resistor shown in FIG. As a result, the variable resistor of the present invention has a T dimension of 1.6 to 1.8 mm, whereas the variable resistor of the present invention has a T dimension of 1.0 mm.

[0038]

According to the present invention, in a variable resistor, a sliding body is placed on a sliding body holding plate disposed on the back surface of an insulating substrate,
In order to rotatably hold the sliding body, the cylindrical portion extending from the sliding body holding plate is caulked.

That is, in this caulking process, it is not necessary to perform the caulking process while sandwiching the insulating substrate, so that it is possible to manufacture a variable resistor that does not cause cracks or cracks in the insulating substrate.

In addition, the height of the variable resistor is substantially equal to the thickness of the sliding member, and the height of the variable resistor can be reduced.

[Brief description of the drawings]

FIG. 1 is a front plan view of a variable resistor according to an embodiment of the present invention.

FIG. 2 is a sectional view in one embodiment of the present invention.

FIG. 3 is a plan view of a back side according to the embodiment of the present invention.

FIG. 4 is an exploded perspective view before assembling in one embodiment of the present invention.

FIG. 5 is a plan view of a lead frame according to the embodiment of the present invention.

FIG. 6 is an exploded perspective view showing a state in which an insulating substrate is mounted on a lead frame according to one embodiment of the present invention.

FIG. 7 is a perspective view showing a positioning state in which an insulating substrate is mounted on a lead frame in one embodiment of the present invention.

FIG. 8 is a front plan view of a conventional variable resistor.

FIG. 9 is a cross-sectional view of a conventional variable resistor.

FIG. 10 is a plan view of the back side of a conventional variable resistor.

[Explanation of symbols]

 1, 101 insulating board 1a, 101a hollow hole 1b convex section 2, 102 resistor film 3, 3a, 3b metal terminal 4, 104 sliding body 4a, 104a body section 4b, 104b ··· Through-hole 4c, 104c · Slider 4d, 104 ··· Adjustment groove 5 ··· Slider holding plate 105 ··· Lead terminal 5a ··· Cylindrical portion 5b ··· Lead terminal 5c ··· Flat plate portion 5d 5e, 5f ... fixed part

Claims (1)

[Claims] 1. A hollow hole for accommodating a sliding body is formed in a central portion, a resistor film having a substantially horseshoe shape is formed on a surface thereof, and metal terminals electrically connected to both ends of the resistor film are provided. A sliding body having a substantially dish-like shape having a through hole formed in the center thereof and having a slider slidingly in contact with the resistor film, and a sliding body at the back opening of the hollow hole of the insulating substrate. A flat portion to be placed, a lead terminal extending from the flat portion to the side surface of the insulating substrate, a cylindrical portion inserted into the through hole and caulked on the upper surface side of the sliding body, and the insulating substrate from the flat portion. And a plurality of fixing portions extending to the surface of the insulating substrate through the side surfaces of the sliding member.