JPH0538809U - Slide type variable resistor - Google Patents

Abstract

(57) [Abstract] [Purpose] In the slide type variable resistor used for various consumer electronic devices, the shape and processing of some terminals for mounting and holding on the printed circuit board, which has been a problem, are complicated. Higher cost, deformation, and entanglement due to the use of the same, and prevention of tilt before soldering and fixing to the printed circuit board, to provide a slide-type variable resistor that is easy to process, has good dimensional accuracy, and good mounting stability. To aim. [Structure] Conductor layer 33 of resistor layer 32 and conductor layer 33
The end portions of the terminals are bent downward so that the heights of the terminal binding portions are substantially the same, all terminals 34 to 37 are formed into a short flat plate, and the terminals are covered with molding resin layers 39, 40, 39 ', 40', and molded. By resin,
By providing the auxiliary legs 42 and 42 'having the protrusions 45 and 45', it is possible to provide a slide type variable resistor which can be easily processed into terminals and has good mounting stability.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention mainly relates to a slide type variable resistor for mounting a printed circuit board which is used in consumer electronic devices such as a cassette tape recorder with a radio, a stereo television receiver and the like.

[0002]

[Prior Art]

 A conventional technique will be described with reference to FIGS.

As shown in FIG. 9, a conventional slide type variable resistor can be roughly classified into a fixed block (I) and a variable block (II), and by combining both blocks prepared in advance at the end, Completed as a slide type variable resistor.

First, as shown in FIG. 10 (A), the fixed block (I) is a resistance substrate in which a linear resistor layer 2 and a conductor layer 3 are formed by printing along the longitudinal direction of the surface of a rectangular insulating substrate. Externally connecting terminals 4, 5 and 6, 7 respectively connected to both ends of the resistor layer 2 and the conductor layer 3 are attached to the plate 1, and the legs of the plate 1 are linearly printed. After forming a leg 4 ', 5'and 6', 7'for soldering to the printed circuit board 8 of the equipment to be used, as shown in FIG. Except for the resistor layer 2 and the conductor layer 3 of the substrate 1, the terminal attachment portions at the upper and lower parallel ends and both ends of the substrate are covered with molding resin layers 9, 9'and 10, 10 'having a constant thickness. At the same time, below the terminal binding parts at both ends, the prints spread in the direction perpendicular to the resistance substrate surface. The board contact portions 11 and 11 'are formed by integral molding resin and completed.

Here, the terminals 6 and 7 attached to both ends of the conductor layer 3 separated from the printed circuit board 8 have portions 6 A and 7 A extending in the extension direction of the linear conductor layer 3. After being bent at a right angle, the extension parts 6B and 7B extending to the lower printed circuit board side are elongated L-shaped, and the soldering leg parts 6'and 7'at the tips thereof face each other. After being inserted into the terminal hole 8'of the printed circuit board 8, the V-shaped taper portion comes into contact with the printed circuit board 8 by the elasticity of the terminal extending portions 6A and 7B. Consideration is given to increase the attachment holding force.

In the movable block (II), as shown in FIG. 9, a sliding contact 13 made of an elastic metal plate is attached to a U-shaped slider 12 made of elastic molding resin. is there.

The slider 12 has a structure in which the upper and lower opposed holding portions 14 and 14 ′ which sandwich the upper and lower parallel resin layers 9 and 9 ′ of the resistance substrate 1 and the holding portions are connected to each other. It comprises a wall surface portion 15 for holding the sliding contactor 13, and a lever portion 16 for moving the slider 12.

The arm portions 17 and 17 ′ and the elastic legs 18 and 18 ′ protruding from the upper and lower opposed holding portions 14 and 14 ′ are resistant to resistance due to stabilization when sliding the slider and constant operating force. It is intended to repress the parallel resin layers 9 and 9'of the substrate 1.

In order to combine the two blocks (I) and (II), the fixed block (I) is placed in the grooves 19 and 19 'of the vertical facing holding portions 14 and 14' of the slider 12 of the movable block (II). Using the elasticity of the resin of the slider 12, so as to fit the parallel resin layers 9 and 9'of the resistance substrate 1 of FIG. Are combined as shown in FIGS. 7 and 8.

At this time, the elastic legs 21 and 22 of the sliding contact 13 are in elastic contact with the linear antibody layer 2 and the conductor layer 3 of the resistance substrate 1, respectively.

In the thus completed slide type variable resistor, the soldering leg portions 4 ′, 5 ′, 6 ′ and 7 ′ of each terminal are inserted into the terminal hole 8 ′ of the printed board 8 of the equipment used. , It is attached by soldering the tip of each leg.

Then, by applying a pressing force to the lever portion 16 of the slider 12, the slider 12 slides linearly using the parallel resin layers 9 and 9 ′ of the resistance substrate 1 as guides, and accordingly, the slider 12 moves. The elastic legs 21 and 22 of the held sliding contact 13 slide while short-circuiting between the resistor layer 2 and the conductor layer 3 on the resistor substrate 1, respectively, and the external connection terminals of the antibody layer 2 are connected. It is possible to change the resistance value between the terminals 4, 5 and the connecting terminals 6, 7 of the conductor layer 3.

[0013]

[Problems to be solved by the device]

 However, in the above-mentioned conventional slide type variable resistor, of the external connection terminals attached to the end portion of the linear print layer on the resistance substrate 1, the end portion of the print layer on the side remote from the print substrate 8 is caulked. The terminals 6 and 7 are long and slender, and can be bent at a right angle in the middle, and the tip is bent into a dogleg shape. (1) The cost is high because it is long and the number of processing steps is large. At the same time, variations in dimensions are likely to occur.

(2) Since the slender variable resistor has the elongated terminals at both outer ends, it is easy to be hit during handling or to be deformed by being entangled with the terminals of another volume.

(3) The tip of this terminal is bent into a dogleg shape to enhance the holding power when it is attached to the printed circuit board. Since the bending part is bent at a right angle in the middle of the lead-out part, the point where the holding force acts shifts from the center line of the variable resistor, so after inserting the tips of the terminals 6 and 6'into the printed circuit board 8, solder it. If a shock or the like is applied before fixing, it tends to tilt in the direction of arrow f in FIG. There was a problem.

The present invention solves such a conventional problem. All external connection terminals attached to the resistance substrate are short flat plates and have a holding force for the printed circuit board. It is an object of the present invention to provide a slide-type variable resistor for mounting on a printed circuit board, which is aligned with the center line of the variable resistor.

[0017]

[Means for Solving the Problems]

 In order to solve the above-mentioned problems, the present invention draws all the printed layer edges of the resistive substrate to the lower part of the resistive substrate, and arranges all external connection terminals attached to the printed layer edges in a linear plate shape. In addition to being short, the resin that covers the periphery of the resistance board and forms the printed circuit board contact part has high heat resistance, and auxiliary legs are integrally provided on this printed circuit board contact part.

[0018]

[Action]

 Therefore, according to the present invention, since all the terminals attached to the resistance substrate are linear and short, the processing cost is low and the deformation is difficult.

Further, the holding force with respect to the printed circuit board can be secured by the auxiliary legs made of molding resin.

[0020]

【Example】

 An embodiment of the slide type variable resistor of the present invention will be described with reference to FIGS.

As shown in FIGS. 1 and 2, the slide type variable resistor of the present invention is completed by combining a fixed block and a movable block as in the prior art, and the structure of the movable block is also the same as in the conventional technology. ..

Therefore, the fixed block will be mainly described, but the same parts as those in the conventional technique will be denoted by the same reference numerals, and the description will be omitted below.

FIG. 3 shows a method of forming a fixed block. In FIG. 3A, 31 is a resistor substrate, and a linear resistor layer 32 and a conductor layer 33 are printed in parallel along the surface longitudinal direction. It is the same as the conventional resistance substrate 1 in that it is formed, but both end portions 33A and 33B of the conductor layer 33 are bent downward and extended to a position lateral to the resistor layer 32.

Then, external connection terminals 34, 35 and 36, 37 of the same size are respectively attached and connected to both ends of the resistor layer 32 and the conductor layer 33, and their legs are not connected. Extending in a direction perpendicular to the printed circuit board to be mounted, soldering legs 34 ', 35' and 36 ', 37' are formed on the printed circuit board 38 of the equipment used.

It is to be noted that all of these terminals 34 to 37 are flat and short, and the same terminals can be used, with the heights of the end portions of the resistor layer 32 and the conductor layer 33 being substantially the same. ..

Then, as shown in FIG. 3B, the terminal binding portions at the upper and lower parallel ends and the left and right ends of the resistance substrate 31 are respectively formed with molding resin layers 39, 39 having a constant thickness, as in the prior art. ′ And 40, 40 ′, and printed circuit board contact portions 41, 41 ′ that are spread out in the direction perpendicular to the surface of the resistance substrate 31 below the terminal binding portions at both ends. On the lower surface of 41, 41 ', auxiliary legs 42, 42', which are parallel to the soldering leg portions 34'-37 'of each terminal, are also formed of an integral heat-resistant resin.

Here, as shown in FIG. 1, after the soldering leg portions 34 ′ to 37 ′ and the heat-resistant resin auxiliary legs 42 and 42 ′ are inserted into the holes 43 and 44 of the printed board 38, the printed board In order to increase the holding force against the heat-resistant resin, the heat-resistant resin auxiliary legs 42, 42 'are provided with protrusions 45, 45' for preventing them from coming out from the printed circuit board holes 44, respectively. The auxiliary legs 42, 42 'are inserted into the holes of the above by utilizing the elasticity.

The sliding variable resistor is completed by combining the fixed block thus formed with the movable block in the same manner as in the conventional example.

In the embodiment shown in FIGS. 1 to 3, the case where the positions of the auxiliary legs 42 and 42 'made of heat-resistant resin and the external connection terminals 34 to 37 are arranged in a straight line are shown. However, due to the wiring of the printed circuit board, etc., as shown in the bottom view of the fixed block in FIG. 4, the positions of the auxiliary legs 42 and 42 'at both ends are shifted from the row of the external connection terminals 34' to 37 '. Of course, they may be arranged in symmetrical positions.

Further, in the above-mentioned embodiment, the case of the single-acting type slide type variable resistor in which a set of the resistor layer 32 and the conductor layer 33 is formed by printing on the resistor substrate 31 of the fixed block is shown. However, as shown in FIG. 5, the present invention is also applied to an interlocking type slide type variable resistor in which two sets of resistor layers and conductor layers 32, 33 and 46, 47 are arranged side by side on a resistor substrate 31. Of course you can.

6 (A) and 6 (B) illustrate an example of a procedure for integrally molding a molding resin layer on the resistance substrate 31 which is the fixed block of the present invention, and the terminals 34 to 37 are provided at the tips. Then, it is attached to the resistance substrate 31 in a state of being connected by the connecting device 48, and as shown in FIG. 2B, the periphery of the resistance substrate 31 is left as it is, and the molding resin layers 39, 39 ', 40, 40' are formed. After covering with, etc., the coupling machine 48 is separated to electrically separate each terminal, thereby continuously automating the processing steps.

[0032]

[Effect of the device]

 As apparent from the above-described embodiment, the present invention provides an auxiliary leg integrally with a molding resin layer that covers the periphery of the resistance board and forms the sliding motion guide portion of the movable block. After the slide type variable resistor is attached, the holding force until it is fixed by soldering is obtained by the elastic force of this auxiliary leg.

The cost increase in the molding process for providing the auxiliary leg does not occur because it is performed in the same molding step, and the heat resistance of the molding resin material is improved, so that there is no problem such as melting of the auxiliary leg during soldering , To improve the function.

Further, in the case where the end portion of the resistor layer or the conductor layer is bent downward and extended to be attached to the connecting terminal, all the connecting terminals should be short straight linear plates. As a result, the processing cost of the terminals will be low, and variations in dimensions will not easily occur.

In addition, the terminals are electrically connected to each other by attaching the terminals to the resistance substrate in a state where the terminals are connected by the connecting device, covering the periphery of the resistance substrate with the molding resin layer, and then disconnecting the connecting device. It is also possible to achieve continuous automation of machining processes by making them independent.

When the positions of the auxiliary legs are arranged symmetrically with respect to the row of terminals for continuity, the holding force acts symmetrically with respect to the center line of the slide type variable resistor, and before the soldering and fixing. Even if a shock or the like is applied to it, it will not tilt in a specific direction.

[Brief description of drawings]

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

FIG. 2 is a side sectional view taken along the line AA ′ in FIG.

3A and 3B are front views for explaining a formation state of a fixed block, which is a main part of the same.

FIG. 4 is a bottom view of the fixed block of the second embodiment.

FIG. 5 is a side view of a fixed block which is a main part of the third embodiment.

FIG. 6A and FIG. 6B are front views for explaining a formation state of a fixed block which is an essential part of the fourth embodiment.

FIG. 7 is a front view of a conventional slide type variable resistor.

8 is a side sectional view taken along the line AA ′ in FIG.

FIG. 9 is an exploded perspective view of the same.

10A and 10B are front views for explaining a formation state of a fixed block, which is a main part of the same.

[Explanation of symbols]

 12 Slider 13 Sliding Contact 31 Resistance Substrate 32 Resistor Layer 33 Conductor Layer 34-37 External Connection Terminal 39, 39 ', 40, 40' Molded Resin Layer 41, 41 'Abutting Part 42, 42' Auxiliary Leg

Claims (4)

[Scope of utility model registration request] 1. A resistive substrate formed by printing and firing a resistive layer and a conductive layer parallel to the surface of a rectangular insulating substrate, and conductively attached to the end portions of each printed layer on both ends of the resistive substrate. ,
A plurality of external connection terminals that are led out in the mounting direction to the printed circuit board on the same plane parallel to the board surface and the upper and lower end surfaces of the resistance board and the terminal attachment parts on the left and right ends are covered with a uniform thickness. At the same time, the heat-resistant resin part with the printed circuit board abutting part that spreads in the direction perpendicular to the resistance board surface at both ends and the auxiliary legs parallel to the terminals on the bottom surface are also used, and the upper and lower parallel resin layers of the resistance board are used as guides. A slide-type variable resistor that is composed of a slider that slides in a straight line and a sliding contact that is attached to this slider and slides while short-circuiting between the resistor layer and the conductor layer of the resistance substrate with the linear movement. vessel. 2. An end portion of at least one of the resistor layer and the conductor layer is bent downward to make the height of the end portion of the resistor layer and the conductor layer substantially the same, and connected to this end portion. The slide-type variable resistor according to claim 1, wherein the respective terminals are attached to each other. 3. A plurality of flat plate terminals, which are attached to both ends of a resistance substrate, are formed by punching out an integrated metal plate, and the attached portions are covered with a heat resistant resin in a connected state. The slide type variable resistor according to claim 1, wherein the slide type variable resistor is individually cut and electrically isolated. 4. Auxiliary legs on the lower surface of a printed circuit board abutting portion made of a heat resistant resin at both ends of the resistance substrate are projected from symmetrical positions of the tips of the respective abutting portions, and the auxiliary legs are extended outward from the printed circuit board holes. The slide type variable resistor according to claim 1 or 2 or 3, characterized in that a protrusion for preventing slipping out is provided.