JPS6340301A - Rotary operation type variable resistor - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a rotary variable resistor used primarily in small consumer audio equipment such as small radios and radio-cassette players.

2. Description of the Related Art Examples of conventional general variable resistors are shown in FIGS. 5 and 6. FIG. 5 is a side sectional view, and FIG. 6 is an exploded perspective view showing the components.

In the figure, reference numeral 1 denotes a resistance board made of an insulating resin material, on the surface of which are arranged a horseshoe-shaped resistor printed layer 2, its starting and ending lead-out parts 3.4, and a circular conductor layer 5 and its lead-out parts 6.
A small circular hole 7 is provided in the center. 8 is an external connection terminal to be attached to the lead-out parts 3, 4.6, and the chain part 8a is connected to the mounting hole 3 of each lead-out part 3, 4.6 of the resistance board 1.
a.

4a and 61L, conduction is fixed.

Reference numeral 9 denotes a sliding contact made of an elastic thin metal plate, which is connected to the resistor substrate 1.
It has an elastic contact portion 10.11 that rotates and slides on the upper resistive printed layer 2 and the circular conductor layer 6 while short-circuiting them,
The dowel (
(not shown) is attached to the lower surface of the knob 13. This knob 13 is made of insulating resin, has a larger outer diameter than the resistor board 1, and has a circular hole 14 in the center. Reference numeral 15 denotes a fixing fitting made of a metal plate, which also has a hole 16 in its center, which holds the knob 13, the resistance board 1, and the fixing fitting 1.
5, and pass the stepped silver 17 through the center holes 14, 7 and 16 from the knob 13 side, and align the tips protruding from the back side of the fixing fitting 15, thereby assembling it as a variable resistor. There is.

At this time, so that the knob 13 can freely rotate around the stepped silver 17, the diameter and thickness of the hole 14 are provided with an allowance, and the protrusion 18 of the fixing metal fitting 15 is provided with an allowance.
A part of a stopper (not shown) is provided near the outer periphery of the stopper for abutting against the rotation angle range of the rotation angle.

When installing this type of variable resistor into a set, insert the mounting foot 19 of the fixing bracket 15 and the three external connection terminals 8 into the holes of the printed circuit board 2o and solder them on the back side. It is attached.

Then, by pressing the outer circumference of the knob 13 with a finger and rotating it, the sliding contact 10.11 rotates and slides on the resistive printed layer 2 and the circular conductor layer 5, and is taken out between the external connection terminals 8. The resistance value changes.

Problems to be Solved by the Invention By the way, variable resistor manufacturers produce variable resistors according to the requests of set manufacturers, and the contents of the requests vary depending on the design of the set.

In this type of variable resistor, the resistance value and resistance change characteristics of the resistance element (printed resistor element 2) are most often changed, followed by the color, shape, etc. of the knob 13. However, in the conventional configuration as described above, these parts that change the most are the basic components for assembly. Therefore, the variable resistor manufacturer cannot prepare for assembly until an order is placed by the set manufacturer, and it is also very inconvenient to automatically assemble many types of products at once.

The present invention aims to provide a variable resistor that can eliminate the above-mentioned problems and further stabilize the positional relationship between the knob and the base portion.

Means for Solving the Problems Therefore, the present invention includes an operating knob made of resin, and a resistor printed layer and a conductive printed layer attached to the operating knob and substantially concentrically formed on one surface of the operating knob. It is equipped with a resistance board, and a base made of insulating resin on which elastic contact bodies having tip contact parts are fixed at positions corresponding to the resistance printed layer and the conductive printed layer on the resistance board. At the same time, this support is passed through the resistance board and the hole in the knob to make the knob rotatable, a step is provided on the support at the part that passes through this knob, a spacer is placed on this step, and the spacer A rotary-operable variable resistor with a locking structure on the upper column.

If the configuration is more than functional, it will be based on the base part, and can easily meet various requests by simply replacing the knob and the resistance board.Furthermore, since a retaining structure is provided on the spacer, it is possible to prevent the knob from being held down too much.

Embodiment An embodiment of the variable resistor of the present invention is shown in FIGS. 1 to 4.

In the figure, reference numeral 21 denotes a circular knob made of molded resin, which has a circular hole 22 in its center and a thin annular portion 23 near the outer periphery of its lower surface.

As shown in FIG. 3, inside the knob annular portion 23, a circular resistance substrate 24 made of an insulating material is arranged so that the circular hole 26 in the center corresponds to the circular hole 22 of the circular knob 21. There is. 'Furthermore, at this time, the notch 26 of the resistance board 24 is fitted into the protrusion 27 of the circular knob 21 without play, thereby positioning and mounting. Furthermore, on this surface, there are a resistor printed layer 28 having a circular shape with a partially cut out portion, and circular conductor printed layers 30 and 31 electrically connected to the terminal ends 29a and 29b on both sides of the resistor printed layer 28, respectively. They are arranged concentrically with respect to the center hole 25 of.

Reference numeral 32 denotes a base portion made of insulating resin, whose plan view is shown in FIG. That is, the circular hole 22 of the circular knob 21 is located at the center of the base portion 32.
The large-diameter support 33b rotatably fits into and supports the circular hole 22 of the knob 21, and the step of the oval-shaped support 33a at the tip protruding upward is made of an elastic material. The knob 21 is held in place by placing a spacer 34 on it and pushing out the upper end of the p-stepped support 33 using a construction method such as heat tightening. Further, the protrusion 32Δ of the base portion 32 comes into contact with the protrusion 27 of the knob 21 and serves as a stopper for regulating the rotation angle range of the knob 210.

Further, the flat plate portion of the base portion 32 is made of an elastic metal plate,
Three independent elastic contact bodies each having contact portions 35, 36, 37 that come into elastic contact with the resistor printed layer 28 and the circular conductor printed layer 30, 31 on the surface of the resistor substrate 24 have elastic legs 3B,
It is fixed by insert molding the root part of 39.40 inside. The elastic legs 3B, 39, 40 are further extended to the outside to form external connection terminal portions 41, 42, 43.

The operation of the variable resistor of this embodiment described above is the same as that of the conventional type.

This variable resistor is constructed as described above, and is assembled by combining the knob 21 with the resistance board 24 attached to the base portion 32 to which the elastic legs 38, 39, 40 are fixed.

Effects of the Invention This is a method of combining a resistance board and a knob, which are likely to be changed, based on a base part that is unlikely to be changed due to the cent design using a variable resistor. Therefore, it is possible for variable resistor manufacturers to prepare the base part to which the elastic contact body is fixed in advance, and also to combine the metal plates for forming the elastic contact body into a continuous hoop shape. It is also possible to introduce continuous automatic assembly based on this pace.

Further, since a spacer is placed on the step of the support that passes through the knob, and a retaining structure is applied to the support on the spacer, the retainer does not fall too low and impede the rotation of the knob.

[Brief explanation of drawings]

Fig. 1 is a partially cutaway perspective view of a rotary variable resistor according to an embodiment of the present invention, Fig. 2 is a plan view of a knob used in Fig. 1, and Fig. 3 is a plan view of a knob used in Fig. 1. 4(a) is a plan view of the base used in FIG. 1, FIG. 4(b) is a cross-sectional view of the resistor board used in FIG. 4(a), and FIG. 6 is a conventional rotating FIG. 6 is a side sectional view of the operated variable resistor and an exploded perspective view of a conventional rotary operated variable resistor. 21...Knob, 24...Resistance board,
28...Resistance printed layer, 30.31...Circular conductor printed layer, 32...Base part, 33...Stepped support, 34...Spacer, 35.36. 37...
・Elastic contact part. Name of agent: Patent attorney Toshio Nakao and 1 other person @1
Figure 3 Figure 4

Claims (1)

[Claims] An operating knob made of resin, a resistive board attached to the operating knob and having a resistive printed layer and a conductive printed layer substantially concentrically on one surface of the resistive board, a resistive printed layer on the resistive board, and a resistive printed layer on the resistive board. A base made of insulating resin is provided with elastic contact bodies having tip contact portions fixed at positions corresponding to each of the conductive printed layers, a support is erected from the base, and the support is connected to the resistor board. A rotary operation type in which a hole in the knob is passed through to make the knob freely rotatable, a step is provided on the column where the knob passes through, a spacer is placed on this step, and the column above the spacer is configured to prevent it from coming off. Variable resistor.