JPH0337842B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a method for manufacturing a sliding member in a rotating electrical component such as a rotating variable resistor or a rotary switch.

[Background of the Invention] As a rotating electric component, for example, a rotating variable resistor is provided with a slider slidably in contact with a resistor formed in an annular shape, and the circumference of the resistor of the slider is By displacing the contact position in the direction, the resistance value can be adjusted. In order to slide the slider, the slider is fixed to an adjustment knob, and by rotating the adjustment knob, the sliding position of the slider relative to the resistor is adjusted. ing.

Here, as a method of manufacturing a sliding member consisting of this slider and an adjustment knob, a hoop material made of a conductive metal material constituting the slider is pressed into a loop-shaped member with contact portions. A slider structure consisting of a slider part and a connecting part that holds the slider part in a state connected to the hoop material is formed, and the slider structure is connected to the hoop material while being connected to the hoop material. The resin that forms the adjustment knob is outsert molded,
It has been known in the past that the connecting portion is then separated from the hoop material.

Therefore, it is necessary to securely fix the slider to the adjustment knob, and also to maintain the slider in a state in which it is firmly pressed against the resistor regardless of its sliding position. The slider portion is formed such that only its contacts and a portion that imparts spring properties to the contacts are exposed from the adjustment knob. Here, the sliding torque of this slider with respect to the resistor is:
It is determined based on the exposed part of the slider from the adjustment knob. If this sliding torque is too large, it will damage the resistor, but in order to reduce this sliding torque, If the exposed portion of the slider is made larger, there is a drawback that the fixation of the slider to the adjustment knob becomes poor. Particularly when miniaturizing this type of electrical component, it has been extremely difficult to ensure that the slider has good fixation to the adjustment knob while also obtaining a desired sliding torque.

[Object of the Invention] The present invention has been made in view of the above-mentioned points, and its purpose is to control the sliding torque of the contact to the resistor in the slider portion of the slider structure to a desired level. It is an object of the present invention to provide a method for manufacturing a sliding member of a variable resistor, which enables continuous and automatic manufacturing of sliding members that can be set to different values.

[Summary of the Invention] In order to achieve the above-mentioned object, the method of the present invention includes a loop-shaped slider portion having contact points and a loop-shaped slider portion that is connected to the slider portion by pressing a hoop material. A slider structure is formed of a loop-shaped embedded part and a connecting part that maintains a connected state between the slider part and the hoop material, and the slider part of this slider structure is An adjustment knob is formed by exposing the part to the outside and performing outsert molding with only the buried part buried, and a leg part is extended to the adjustment knob and connected to the hoop material, and the connecting part is By separating it from the hoop material, folding the slider part toward the tip side of the adjustment knob while keeping it connected to the hoop material by the leg part, and separating the corresponding rear leg part from the hoop material. The present invention is characterized in that it provides a method for manufacturing a rotating electric component having a wide exposed portion and a desired sliding torque.

[Embodiments of the Invention] Hereinafter, embodiments of the present invention will be described in detail based on the drawings. In this embodiment, a sliding member in a rotary variable resistor will be described as an example of a rotary electric component.

The rotary variable resistor has a structure as shown in FIG. That is, in the figure, 1 is a cylindrical insulating case with a bottom, and a substrate 2 made of an insulating material such as synthetic resin film or ceramic is installed on the bottom wall of the insulating case 1. A resistor 3 is formed by printing or other means, and terminals 4 and 5 are connected to both ends of the resistor 3.
The tip portion of the insulating case 1 projects outward from the insulating case 1.

On the resistor 3, a loop-shaped slider portion 6a of a slider structure 6 made of a conductive spring material and a contact portion 6b are slidably abutted. This slider structure 6 has its buried portion 6c fixed to a first adjustment knob 7 rotatably attached to the insulating case 1, and the slider structure 6 has a buried portion 6c fixed to the first adjustment knob 7 rotatably attached to the insulating case 1, and has a buried portion 6c fixed to the insulating case 1 on the side opposite to the mounting side of the first adjustment knob. It is also engaged with a second adjustment knob 8 extending through the bottom of 1 . These first and second adjustment knobs 7 and 8 have operation grooves 7a and 8 that are rotatably operated by a jig such as a screwdriver.
a is formed respectively. Furthermore, a terminal 9 connected to the slider 6 protrudes from the second adjustment knob 8 side.

The rotary variable resistor constructed as described above is used with its terminals 4, 5, 9 attached to the printed wiring board 10, and the first and second adjustment knobs 7, 8 A desired resistance value can be obtained by appropriately rotating either one of the two.

Next, a method for manufacturing a sliding member will be explained based on FIGS. 2 to 4.

First, as shown in FIG. 2, a hoop material 11 made of a conductive metal material is engaged with a feeding member (not shown) into engagement holes 12, 12, . . . formed at both ends of the hoop material 11. By pressing the hoop material 11, the slider portion 6a having the contact portion 6b and the buried portion 6c are formed into a loop shape, and the slider portion 6a and the buried portion 6c are formed into a loop shape. Buried part 6
A slider structure 6 is formed by forming a connecting portion 6d between the hoop member c and connecting portions 6e and 6e that keep the slider portion 6a connected to the hoop material 11.

After forming the slider structure 6 by press working as described above, the buried portion 6c is housed in a mold, and the slider portion 6a is exposed to the outside and outsert molded with synthetic resin. By doing,
A first adjustment knob 7 is formed as shown in FIG. At this time, the resin is bridged between the forming part of the first adjustment knob 7 and the attachment holes 13, 13, 13, .

Thereafter, as shown in FIG. Turn around. As a result, the entire loop-shaped slider portion 6a applies a pressing force to the resistor 3 of the contact portion 6b. Moreover, even if the slider portion 6a is separated from the hoop material 11 in this way, the first adjustment knob 7 and the hoop material 1
1 is connected to the hoop material 11 by the leg portion 14, so that it will not fall off from the hoop material 11.

Furthermore, by separating the leg portions 14, the sliding member formed by incorporating the slider structure 6 into the first adjustment knob 7 is separated from the hoop material 11. and,
A resistor is assembled by incorporating this sliding member into the insulating case 1.

Thus, as described above, the entire slider portion 6a is exposed, and the slider portion 6a is connected to the buried portion 6c.
It is possible to press the resistor 3 of the contact portion 6b using the bent portion of the continuous portion 6d between the slider portion 6a as a fulcrum, by appropriately setting the size, thickness, etc. of the slider portion 6a. A desired pressing force, that is, sliding torque can be obtained, there is no problem of damaging the resistor 3, and stable operation as a variable resistor can be ensured. Moreover, the buried part 6c
Since the entire slider structure 6 is embedded within the first adjustment knob 7, the slider structure 6 is fixed to the first adjustment knob 7 in an extremely stable manner.

Further, as described above, the slider structure 6 is separated from the hoop material 11 before bending the slider portion 6a, but there is a gap between the first adjustment knob 7 and the hoop material 11. Since the knobs 7 are held in a connected state by the resin legs 14, they do not fall off from the hoop material 11, and subsequent steps can be carried out continuously and automatically.

[Effects of the Invention] As detailed above, the method of the present invention involves insert-molding the buried portion of the slider portion of the slider structure together with the adjustment knob in a state where the slider portion is exposed to the outside, and at this time, the adjustment is performed. Since the leg section maintains a bridge between the knob and the hoop material, even if the slider section is separated from the hoop material in a subsequent process, it will still be connected to the hoop material by the leg section. It is now possible to perform processes such as folding back the slider part while it is connected to the hoop material. It is possible to continuously and automatically manufacture a sliding member of a rotary electric component that has good fixation to an adjustment knob and can operate smoothly.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a rotary electric component showing an embodiment of the present invention, and FIGS. 2, 3, and 4 are explanatory views of the manufacturing process of a sliding member. 3: Resistor, 6: Slider structure, 6a: Slider portion, 6b: Contact portion, 6c: Buried portion, 6d: Connecting portion, 7: First adjustment knob, 11: Hoop material.

Claims (1)

[Claims] 1. A slider part that is formed into a loop shape by pressing a hoop material and has a contact point, an embedded part connected to the slider part, and a space between the slider part and the hoop material. A slider structure consisting of a connecting part that holds the slider structure in a connected state is formed, and an adjustment knob is formed by outsert molding a synthetic resin with the buried part of the slider structure in the buried state. At the same time, a leg portion is extended to the adjustment knob and connected to the hoop material, the connecting portion is separated from the hoop material, the slider portion is folded back to the tip side of the adjustment knob, and then the leg portion is connected to the hoop material. 1. A method of manufacturing a sliding member for a rotary electrical component, characterized in that a portion of the sliding member is separated from the hoop material.