JP2000299211A - Motor drive type sliding variable resistor and assembling method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a small-sized motor drive type sliding variable resistor of low height, having a short control lever with a toothed belt and a toothed pulley, etc., exposed to the outside, and to reduce assembling man-hours. SOLUTION: A metal case 15 is extended in the longitudinal direction and integrally provided with the mouthing part of a motor 3 and the mounting part of a follower pulley 6. A ring-like toothed belt 7 is stretchingly provided in the metal case 15, and the slidingly moving body 16 which retains an elastic contact part 11, is moved rectilinearly. As a result, the height of the entire body can be made low, and moving parts are not exposed to the outside.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motor and a manually driven slide type variable resistor mainly used for an adjusting section of a mixer for audio equipment and the like and a method of assembling the same.

[0002]

2. Description of the Related Art The technique of a conventional motor-driven slide type variable resistor will be described with reference to FIGS. 9 and 10. FIG.

FIG. 9 is an external perspective view of a conventional motor-driven slide type variable resistor. In FIG. 9, reference numeral 1 denotes an elongated box-shaped frame with an open top formed by processing a metal plate.
A slide-type variable resistor section 2 is attached to the lower surface of the central portion along the longitudinal direction by a screw 1A, a motor 3 is vertically attached to one end, and a toothed pulley 5 is Is mounted, and the frame 1
A driven pulley 6 is rotatably mounted opposite to the toothed pulley 5 at the other end thereof, and the toothed pulley 5 and the driven pulley 6
Between them, a ring-shaped toothed belt 7 is stretched,
The intermediate portion is fixed to the operation lever 8 of the variable resistor section 2.

The variable resistor section 2 is a general manual slide type variable resistor. As shown in a partial cross-sectional front view of FIG. 10, an upper operation lever 8 has an elongated box-shaped metal case 9 with an upper bottom surface. While projecting from the linear slit 9A,
A sliding body 12 holding an elastic contact 11 on a lower surface is provided in an elongated box-like portion composed of a metal case 9 and a resistance substrate 10,
It is configured to be accommodated so as to be linearly movable in the longitudinal direction in the box-shaped portion.
Is such that the resistance value is changed by linearly sliding on the resistance layer of the resistance substrate 10.

[0005] Reference numeral 13 denotes a shield plate for electrically shielding the resistance substrate 10 of the variable resistor section 2 from peripheral circuits of used electronic equipment.

There are two methods for moving the sliding body 12, a method for moving the motor 3 via the toothed belt 7, and a method for manually moving the same via the knob 14 attached to the operation lever 8. It could be operated.

[0007]

However, the conventional motor driven slide type variable resistor is provided with a general manual slide type variable resistor on the lower surface of an elongated metal plate box-shaped frame 1 having an open upper surface. The height dimension of the motor-driven slide-type variable resistor as a whole is larger than the height of the slide-type variable resistor portion 2 by the height of the frame 1 because the metal case 9 and the screw 1A are attached to the container. The operating lever 8 is also long, and the operating lever 8 is long, so that rattling of the operating lever at the time of manual operation is conspicuous, and the toothed belt 7 and the toothed pulley 5, which are movable parts, are external. Because it is exposed to, care must be taken to avoid damage when incorporating it into the electronic device used,
Further, there is a problem that the number of assembling steps for the motor-driven slide variable resistor as a whole also increases.

The present invention solves such a conventional problem. The entire height is small, the occupied portion in the used set is small, and the operation lever is short.
It is another object of the present invention to provide a motor-driven slide type variable resistor in which a movable portion, such as a toothed belt or a toothed pulley, is not exposed to the outside, and further reduces the number of assembly steps.

[0009]

In order to achieve the above object, a motor driven slide type variable resistor according to the present invention is provided by extending a metal case of a slide type variable resistor portion in a longitudinal direction, and installing a motor mounting portion and a motor. The sliding pulley holding the elastic contact is moved linearly while a ring-shaped toothed belt is stretched in the metal case while the mounting portion of the driven pulley is integrally provided.

[0010] Accordingly, the overall height is small, the occupied portion in the used set is small, rattling of the operation lever during manual operation is less noticeable, and the toothed belt and toothed pulley, etc., which are movable parts, are not included. Since it is housed in the metal case, it is hardly damaged during handling, and a motor-driven slide type variable resistor with a small number of assembling steps can be obtained.

[0011]

DETAILED DESCRIPTION OF THE INVENTION The invention according to claim 1 of the present invention is a box-shaped metal plate having an open lower surface and a flat slit formed on a flat upper surface and having a predetermined length along a longitudinal direction. A driven pulley having an opening of a predetermined size sandwiching a locking claw projecting downward from one end of the slit toward the distal end side, and a lower surface at a position distal to the other end. A metal case having an elongated resistance substrate held by a lower end of a side wall of the metal case facing the slit of the metal case and having a linear resistance layer on an upper surface thereof; and a metal case and a resistance substrate. And an operation lever protruding outward from a slit of the metal case on an upper surface, and an elastic contact that resiliently contacts a resistance layer of the resistance substrate on a lower surface. Sliding body with teeth attached to the tip of the rotating shaft The metal case is attached to the metal holding plate held at the lower end of the side wall of the metal case so that the coil is located in the opening on the tip side of one end of the slit in the metal case. A motor located
A motor drive comprising a ring-shaped toothed belt which is stretched between a toothed pulley and a driven pulley at the end of a rotating shaft of the motor in the metal case, and an intermediate portion is fixed to an upper surface side of the sliding body. It is a slide type variable resistor,
The overall height is small and the occupied part in the used set is small, the rattling of the operation lever during manual operation is not noticeable, and the movable part such as a toothed belt and toothed pulley is housed in a metal case. Therefore, there is an effect that a motor-driven slide type variable resistor that is hardly damaged during handling and that requires a small number of assembly steps can be obtained.

According to a second aspect of the present invention, in the first aspect, the metal holding plate for mounting and fixing the motor below the opening of the metal case is extended to the back surface of the resistance substrate, and In addition to the operation according to the first aspect of the present invention, the shield substrate of the motor-driven slide type variable resistor is electrically shielded from peripheral circuits of the electronic device used. Shield plate,
This has the effect that it can be provided at low cost without increasing the number of components.

According to a third aspect of the present invention, in the first or second aspect, the screw holes of the metal holding plate for mounting and fixing the motor with screws are elongated in a predetermined range in the longitudinal direction of the metal case. In the process of assembling the motor-driven slide type variable resistor, the position where the motor is mounted and fixed to the metal holding plate is adjusted, and the toothed pulley at the tip of the rotating shaft of the motor and the other end of the metal case are adjusted. This has the effect that the tension of the toothed belt stretched between the driven pulleys can be set to an optimum value.

According to a fourth aspect of the present invention, in the invention according to any one of the first to third aspects, the locking claw projecting downward from the upper bottom surface of the metal case is provided on the slit side of the opening. When the motor-driven slide type variable resistor is assembled, the locking state of the toothed belt temporarily fixed to the locking claw portion can be visually checked from above, and this portion can be checked. This has the effect that the work of detaching from the device can be easily performed.

According to a fifth aspect of the present invention, a sliding body having a toothed belt fixed to an upper surface side portion is accommodated in a metal case so that an operation lever protrudes from a slit and is engaged with a driven pulley in the metal case. With the toothed belt temporarily fixed to the claw part, the metal holding plate and the resistance board to which the motor is mounted and temporarily fixed are mounted on the metal case, and then the toothed belt is removed from the locking claw part and the motor rotates. 4. A method for assembling a motor-driven slide type variable resistor according to claim 3, wherein a screw is engaged and fixed at a predetermined position in an elongated screw hole by engaging with a toothed pulley at a shaft tip. This has the effect that the slide-type variable resistor can be assembled efficiently and in an optimal state.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

The same components as those described in the section of the related art are denoted by the same reference numerals, and detailed description thereof will be omitted.

(Embodiment) FIG. 1 is a front view of a partial section of a motor-driven slide type variable resistor according to an embodiment of the present invention, and FIG. 2 is an exploded perspective view of the same.
Reference numeral 15 denotes an elongated box-shaped metal case formed by processing a metal plate and having an open bottom surface, and having a linear slit 15A of a predetermined length along the longitudinal direction at the center of the flat upper bottom surface. At the distal end side of one end of 15A, there is provided an opening 15C having a large width and a locking claw 15B protruding downward from the slit-side end thereof.
A driven pulley 6 similar to that of the prior art is attached to the lower surface of the tip of the 5A from the other end by a stud 6A.

The slit 15A of the metal case 15
A resistance substrate 10 having a linear resistance layer 10A on the upper surface is held at the lower end of the side wall portion at a position opposite to the above, and is constituted by the metal case 15 and the resistance substrate 10. A sliding body 16 holding an elastic contact 11 on the lower surface is accommodated in the box-shaped portion so as to be linearly movable along the longitudinal direction of the elongated box-shaped portion, and an operation lever 17 provided on the upper surface thereof is provided.
Are projected upward from the slit 15A of the metal case 15, but the operation lever 17 is shorter than in the case of the related art.

The motor 3 mounted on the metal holding plate 18 is held below the opening 15A of the metal case 15, and the toothed pulley 5 mounted on the tip of the rotating shaft 4 has
It is arranged in a position corresponding to the driven pulley 6 in the metal case 15.

The ring-shaped toothed belt 7 made of a material such as rubber and stretched between the toothed pulley 5 and the driven pulley 6 in the metal case 15 has an intermediate portion whose upper surface is the upper surface of the sliding body 16. Is fixed to the toothed connection groove 16A on the side of the operation lever 17.

The metal holding plate 18 on which the motor 3 is mounted is extended to the lower surface of the resistance board 10. The extension 18A is used to electrically shield the resistance board 10 from the surrounding area. It serves as a shield plate.

The motor-driven slide type variable resistor according to the present embodiment is configured as described above, and an assembling method will be described below with reference to the drawings.

First, as shown in the external perspective view seen from the lower surface side of FIG. 3, the slit 15A on the opposite side to the side where the opening 15C and the locking claw 15B are provided on the upper bottom surface of the metal case 15. The driven pulley 6 is attached to the inner side on the tip side from the end by the stud 6A.

Next, as shown in the external perspective view of FIG. 4, a ring-shaped toothed belt is inserted into the toothed connecting groove 16A on the side of the operation lever 17 on the upper surface of the slide 16 having the elastic contact 11 mounted on the lower surface. Insert and fix the middle part of 7.

Then, as shown in the external perspective view seen from the lower surface side of FIG.
The operation lever 17 is projected upward from the slit 15A, and the toothed belt 7 is temporarily fixed to the driven pulley 6 and the claw portion 15B on the inner bottom surface of the metal case 15.

On the other hand, as shown in the external perspective view of FIG. 6, two screw holes 18B provided in an elongated shape along the longitudinal direction of the elongated metal holding plate 18 integrally having an extension 18A as a shield plate. By temporarily tightening the passed screw 19, the motor 3 having the toothed pulley 5 attached to the tip of the rotating shaft 4 is attached and fixed to the metal holding plate 18 in advance.

As shown in the partial cross-sectional front view of FIG. 7, the resistance substrate 10 having the resistance layer 10A on the upper surface is provided at the lower end of the side wall of the metal case 15 accommodating the toothed belt 7 and the sliding body 16. And a metal holding plate 18 on which the motor 3 is mounted and fixed, such that the resistance substrate 10 faces the slit 15A of the metal case 15 and the motor 3 is positioned below the opening 15C. The fixing claw 15D is bent and held.

At this time, the extension 18A of the metal holding plate 18 is mounted so as to cover the lower surface of the resistance substrate 10,
The elastic contact 11 on the lower surface of the sliding body 16 is combined with the zero resistance layer 10A so as to be in step contact.

Thereafter, as shown in the top view of FIG. 8, a jig such as tweezers is inserted while visually confirming from the opening 15C on the upper bottom surface of the metal case 15, and the locking claw 15B on the side thereof is inserted. Remove the temporarily fixed toothed belt 7 and remove the motor 3
Screw 19 which is engaged with the toothed pulley 5 at the tip of the rotary shaft 4 and is passed through an elongated screw hole 18B of the metal holding plate 18.
The position of the motor 3 is shifted while slightly loosening, the tension of the toothed belt 7 is set to an optimum state, and the screw 19 is strongly fastened and fixed. The vessel is completed.

A method of moving the sliding body 16 of the motor-driven slide type variable resistor assembled as described above and shown in FIG. 1 by the motor 3 via the toothed belt 7, and an operation lever Knob 14 attached to 17
It can be operated in two ways, that is, a method of manually moving through the same as in the prior art.

As described above, according to the present embodiment, the overall height is small, the occupied portion in the used set is small, the operation lever is short, and the toothed belt or the toothed pulley as the movable part is provided. And the like are not exposed to the outside, and a motor-driven slide-type variable resistor with less assembly steps can be obtained.

[0033]

As described above, according to the present invention, the overall height is small, the occupied portion in the set to be used is small, the rattling of the operation lever at the time of manual operation is less noticeable, and the movable portion is further provided. Since the toothed belt, the toothed pulley and the like are housed in the metal case, there is an advantage that a motor-driven slide type variable resistor and a method for assembling the same can be obtained which are less likely to be damaged during handling and which require less assembly steps. The effect is obtained.

[Brief description of the drawings]

FIG. 1 is a front view of a partial cross section of a motor-driven slide variable resistor according to an embodiment of the present invention.

FIG. 2 is an exploded perspective view of the same.

FIG. 3 is an external perspective view illustrating the assembling method.

FIG. 4 is an external perspective view illustrating the assembling method.

FIG. 5 is an external perspective view illustrating the assembling method.

FIG. 6 is an external perspective view illustrating the assembling method.

FIG. 7 is a front view of a partial section illustrating the assembling method.

FIG. 8 is a top view illustrating the assembling method.

FIG. 9 is an external perspective view of a conventional motor-driven slide variable resistor.

FIG. 10 is a front view of the same partial section.

[Explanation of symbols]

 Reference Signs List 3 motor 4 rotating shaft 5 toothed pulley 6 driven pulley 6A stud 7 toothed belt 10 resistance board 10A resistance layer 11 elastic contact 14 operation knob 15 metal case 15A slit 15B locking claw 15C opening 15D fixing claw 16 Sliding body 16A Toothed connecting groove 17 Operation lever 18 Metal holding plate 18A Extension 18B Screw hole 19 Screw

Claims (5)

[Claims] 1. An elongated metal plate box having an open bottom surface, having a flat upper surface having a linear slit of a predetermined length along a longitudinal direction, and a lower end located at a tip end side than one end of the slit. A metal case having an opening of a predetermined size with the locking claw protruding to the opposite side, a driven pulley attached to the lower surface at a position on the tip side from the other end, and a slit in this metal case An elongated resistive substrate which is opposed to the lower end of the side wall of the metal case and has a linear resistive layer on its upper surface, and is held between the metal case and the resistive substrate so as to be linearly movable along the longitudinal direction thereof. A sliding body having an operation lever projecting outward from the slit of the metal case on the upper surface, and holding an elastic contact elastically contacting the resistance layer of the resistance substrate on the lower surface;
Attached to the metal holding plate held at the lower end of the side wall of the metal case so that the toothed pulley mounted at the end of the rotating shaft is located in the opening on the tip side of the one end of the slit in the metal case. And a motor positioned below the opening, and in the metal case, stretched between a toothed pulley and a driven pulley at the end of a rotating shaft of the motor, and an intermediate portion is provided on an upper surface side of the sliding body. A motor-driven slide type variable resistor consisting of a fixed ring-shaped toothed belt. 2. The motor-driven slide according to claim 1, wherein a metal holding plate for mounting and fixing the motor below the opening of the metal case is extended to the back surface of the resistance substrate to constitute a shield plate of the resistance substrate portion. Type variable resistor. 3. The motor-driven slide type variable resistor according to claim 1, wherein a screw hole of the metal holding plate for mounting and fixing the motor with a screw is elongated in a longitudinal direction of the metal case within a predetermined range. . 4. The motor-driven type according to claim 1, wherein a locking claw projecting downward from an upper bottom surface of the metal case is provided at an end of the opening on the slit side. Slide type variable resistor. 5. A sliding body having a toothed belt fixed to an upper surface side portion is accommodated in a metal case, an operation lever is protruded from a slit, and a driven pulley and a locking claw portion in the metal case are provided with a toothed belt. After the metal holding plate and the resistance board to which the motor is mounted and temporarily fixed are mounted on the metal case, the toothed belt is removed from the locking claw and the toothed pulley at the end of the motor's rotating shaft is 5. The method for assembling a motor-driven slide type variable resistor according to claim 3, wherein the screw is engaged and a screw is fastened and fixed at a predetermined position in the elongated screw hole.