JPS62143403A - Rotary operation type variable resistor - Google Patents

Abstract

(57) [Summary] 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 small variable resistor with an operating knob used mainly in small consumer audio equipment such as /J\ type radio-cassette players.

Conventional technology An example of a conventional small variable resistor with a general operation knob is shown in No. 6.
7 and 7. FIG. 6 is a side sectional view, and FIG. 7 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 resistance printed layer 2, its starting and ending lead-out parts 3, 4, and a circular conductor layer 5 and its lead-out part 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 its chain part 8a is connected to the mounting hole 3a, 4a of each lead-out part of the resistance board 1.
, 6a, conduction is fixed. Reference numeral 9 denotes a sliding contact made of an elastic thin metal plate, which has an elastic contact portion 10.11 that rotates and slides on the resistor printed layer 2 and the circular conductor layer 3 on the resistor substrate 1 while short-circuiting them. 1. It is attached to the lower surface of the knob 13 by passing a dowel (not shown) of the disc-shaped knob 13 through the hole 12a of the fixing portion 12. The 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.
have. Reference numeral 15 denotes a fixing fitting made of a metal plate, which also has a hole 16 drilled in its center.The knob 13, the resistance board 1, and the fixing fitting 15 are stacked on top of each other, and these center holes 14, 7, and 16 are formed. Stepped silver 1
7 from the knob 13 side and the end portion protruding from the back side of the fixing metal fitting 15 is housed to be assembled as a variable resistor.

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 attaching this type of variable resistor to the center, 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 20' and solder them on the back side. It is attached.

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 resistor print layer 2 and the circular conductor layer 3, and the resistance value taken out between the external connection terminals 8 changes. It is something to do.

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 (resistance printed layer 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.

In addition, a resistor printed layer 2 and a circular conductor layer 5 on the resistor substrate 1 are also included.
are arranged as shown in the diagram, and the terminals are installed at position 3.
In order to align a, 6a, and 4a, it is necessary to draw out the lead-out part 6 from the circular conductor layer 5 through between both end lead-out parts 3.4 of the resistor print layer 2, so the circular shape of the resistor print layer 2 Since the cutout portion (the distance between the two end portions) becomes large, there is a drawback that the effective rotation angle as a variable resistor cannot be made very large.

Furthermore, when attaching this type of variable resistor to a printed circuit board, if a large amount of soldering heat is applied to the external connection terminal 8, the heat will cause the terminal addition hole 3a of the resistor board 1 to
, 6a, and the vicinity of 4a shrinks in the thickness direction to form the terminal chain portion 8a.
There was also a problem in that the squeezing force was weakened, and the contact between the terminal 8 and each lead-out portion 3, 4.6 became unstable.

The present invention aims to provide a rotationally operated variable resistor that can eliminate the above-mentioned drawbacks.

Means for Solving the Problems The present invention attempts to solve the above problems by integrating a sliding contact with an external connection terminal and fixing it to the base, and rotating the resistor board together with the knob. It is something to do.

Function: By taking the above-mentioned measures, the present invention has the same function as the conventional type, and can solve the problems of the conventional product.

Embodiment An embodiment of a small variable resistor with an operating knob according to the present invention is shown in FIGS. 1 to 4.

FIG. 1 is a side sectional view, and in the figure, reference numeral 21 is a circular knob made of molded resin, which has a support 22 at its inner center with a non-circular base 22a and a circular tip 22b, and near the outer periphery. has a thin annular portion 23. Furthermore, the second
The figure is a plan view of the circular knob 21.

As shown in the plan view in FIG. 3, a circular resistance board 24 made of an insulating material is attached to the inside of the knob ring part 23, and a non-circular hole 25 in the center thereof is connected to the non-circular part at the base of the knob support. It is positioned by fitting it loosely into 22a. Then, on its (one side) surface, there is a resistive printing layer 26 in the shape of a partially chipped circular shape, and both ends 27 of the cutout portion of the resistive printing layer 26 . Circular conductive printed layers 28 and 29 electrically connected to the resistor printed layers 28 and 27b are arranged concentrically with respect to the center hole 25 on the inner and outer peripheries of the resistive printed layer 26, respectively.

Reference numeral 3o denotes a base portion made of insulating resin, and FIG. 4(a) is a plan view thereof, and FIG. 4(b) is a cross-sectional view taken along line A-A.

That is, the base portion 30 has a stepped hole 31 in the center that supports the column 22 of the circular knob 21, and the small diameter portion 31b rotatably fits and supports the circular portion 22b at the tip of the column of the knob 21. The knob 21 is held by inflating the protruding tip 22c using a method such as heat containment. Further, the flange 32 on the outer periphery of the stepped hole large diameter portion 31a serves to prevent the resistance board 24 fitted into the non-circular portion 22a of the support base of the knob 21 from being removed, and the protrusion 30a on the outer periphery serves as a protrusion on the outer periphery of the knob. It comes into contact with the knob 21a and serves as a stopper to restrict the rotation angle range of the knob 21.

Further, the flat plate portion of the base portion 30 has three contact portions 34, 35, and 36 made of an elastic metal plate and having elastic contact portions 34, 35, and 36 that come into elastic contact with the resistor print layer 26 and the circular conductor print layer 28, 29 on the surface of the resistor substrate 24. An independent elastic contact body has its elastic legs 37.38
．． The base part of 39 is fixed by insert molding in an insulating resin, and the elastic legs 37, 38, 39 are further extended and bent to the outside to form external connection terminal parts 40, 41.
It forms ゜42.

When attaching the variable resistor of this embodiment to a set, the pedestal part 43 of the base part 30 is brought into contact with the printed circuit board surface as shown in FIG.
It can be attached by inserting it into the hole of the printed circuit board 44 and soldering it on the back side.

The resistor of this embodiment described above operates as a variable resistor in the same manner as the conventional type.

The variable resistor of the present invention is constructed as described above, and is assembled by combining the knob 21 on which the resistance board 24 is attached to the base portion 30 on which the elastic contact bodies 37, 38, 39 are fixed. That is, the system combines the resistance board 24 and the knob 21, which are likely to be changed, based on the base portion 30, which is unlikely to be changed depending on the design of a set using a variable resistor.

Therefore, in the variable resistor manufacturer, the elastic contact body 37
．． It is possible to prepare the base part 3o to which 38 and 39 are fixed in advance, and also to connect the metal plates for forming the elastic contact body in a continuous hoop shape, and to use this as a base for continuous fabrication. It is also possible to introduce automatic assembly.

In addition, unlike the conventional type, there is no need to pass a lead-out section between both ends 27a and 27b of the resistor printed layer 26 on the resistor board 24, so the effective rotation angle as a variable resistor is increased. be able to.

Furthermore, when attaching the variable resistor to the printed circuit board of the set, even if it is affected by soldering heat, the terminal parts 40, 41, 42 and the contact parts 34, 35, 36 to be soldered are formed of an integrated metal plate. Therefore, there will be no contact failure during this time.

In addition, in a rheostat type variable resistor that uses only one terminal of the resistance element (resistance printed layer), one of the circular conductor printed layers and the elastic contact body on the resistance substrate 24 are connected to one terminal as shown in FIG. Since the number of resistors can be omitted, a variable resistor with a smaller outer diameter can be realized.

As described above, the present invention has very high practical value.

[Brief explanation of drawings]

Fig. 1 is a side sectional view of a rotary-operable variable resistor with a knob according to an embodiment of the present invention, Fig. 2 is a plan view of the knob used in Fig. 1,
Figure 3 is a plan view of the resistor board used in Figure 1, and Figure 4 (
a) is a plan view of the base used in FIG. 1; FIG. 1(b) is a plan view of the base portion used in FIG.
5 is a plan view of another embodiment of the resistor board, FIG. 6 is a side sectional view of a conventional rotary-operable variable resistor with an operating knob, and FIG. 1 is an exploded perspective view of a conventional rotary-operable variable resistor with an operating knob. 21... Knob, 22... Knob post, 22
a... Prop base, 22b... Prop tip, 2
3... Knob annular portion, 24... Resistance board, 26--Resistance printed layer, 27a, 27b, end portion of resistor print image, 28.29... Circular conductor printed layer, 3o. ...
... Base part, 31 ... Stepped hole, 32 ... Hole outer periphery flange, 34, 35° 36 ... Elastic contact part, 37, 3
8.39...Elastic contact (leg), 40, 41.
42... External connection terminal section, 43... Pedestal section, 44... Printed circuit board. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
figure! Figure 32 Figure 3 Figure 4

Claims (1)

[Claims] A resistive printing layer arranged concentrically with a part of the circle missing,
A resistor board, which is continuous with both ends of this resistor printed layer and has a circular conductor printed layer on one side surface arranged on the inner and outer peripheries of this resistor printed layer, and a resistor on the resistor board consisting of an elastic metal thin plate. an elastic contact body having a tip contact portion at a position corresponding to each of the printed layer and the inner and outer conductive printed layers; an operating knob formed of molded resin or the like and fitted into the non-circular hole of the resistor board and having a support; and a base portion formed of insulating resin and connected by the pillar portion of the knob, and provided with a fixing portion for the elastic contact body.