JPS6035205Y2 - Sliding contact mounting structure for small electronic components - Google Patents

Description

[Detailed description of the invention] The present invention is based on the structure of a sliding contact (hereinafter referred to as a slider) of a small variable resistor, a small switch, etc., and the combination of this slider and a slider mounting body made of an insulator. This relates to the mounting structure.

When fixing a slider made of an elastic metal plate to an operating body made of a thermoplastic mold in a variable resistor or the like, it is desired that the positioning be accurate, that there will be no backlash, and that the work be easy.

Conventionally, the first method of attaching the slider to the rotating shaft is to provide a hole for positioning in the slider 3' as shown in Fig. 7A, and to attach and penetrate the hole with thermoplastic material. Protrusions 42' are provided on the plastic mold rotating shirt 4a,
There is a method to fix the slider by crushing the protrusion after penetration, and a second method is to fix the slider by crushing the protrusion, as shown in the opening in FIG.
There is a method of fixing the movable shaft by bending the claw into the engagement notch of the movable shaft.

Although the first method is relatively easy to work with, it requires jigs and tools for crushing, has problems with the reliability of caulking the plastic protrusions 42, and has the disadvantage of low heat resistance.

The second method requires the steps of creating and bending the pawl 30' during parts creation and assembly for the slider, which is poor workability, and if the bending is incomplete, the contact piece is pressurized. When pressing, the slider floats, causing the contact pressure to deviate from the design value.Also, since the relatively expensive elastic slider plate has a pair of pawls 30', the material yield during the press operation is low. It had the disadvantage of increasing material costs.

Here, as a method of attaching the slider to a slider attachment part (slider receiver) made of synthetic resin fixed to the shaft in the first method, and improvements thereto, ■U.S. Patent Specification No. 28
There are inventions, ideas, etc. described in No. 29224 (B) and No. 359771 (C) Utility Model Application Publication No. 5O-7994K.

Here, an explanation will be given with reference to FIG. 8, which shows an embodiment of this conventional slider mounting structure, focusing on (C).

That is, when the slider 3' is attached to the slider mounting part (slider receiver) 1' made of synthetic resin, the free end 5' which is the sliding contact of the slider 3' is subjected to a load. ), so in order to receive this, the slider and the engagement protrusion for the mounting fulcrum of the slider mounting part (
Here, a protrusion 5'' is provided at the free end of the slider strangling part 4', 4'' on the opposite side to the contact free end 5',
The slider mounting part (slider receiver) 1' that engages with this is a square-shaped or protruding receiver protruding from the upper surface 2' of the hole 7' of the part 7'.
It has a structure in which it is inserted in the horizontal direction.

In this way, the contact load of the free end 5' is applied to the holding force because the strong receiver, which is located quite far away from the engagement protrusions 4' and 4'' for the mounting fulcrum of the slider, receives the contact load at the part 7'. was made strong.

In (4) above, it is almost the same as (C), but the mounting fulcrum of the slider and the slider attachment part (slider receiver) is a knob which is the slider attachment part and is rotatably fixed. This is a groove in the shaft that is fixed to the board that is attached to the shaft, and is supported by the groove rather than by a stranglehold.

In addition, in (B), the bent portion of the slider that is engaged and supported by the T-shaped protrusion serves as a fulcrum.

However, (in C1, the engagement between the engagement hole of the slider 3' and the engagement protrusions 4' and 4'' of the slider attachment part 1' has some play in the horizontal direction due to a fitting error, and this causes the sliding Accurate positioning of mover 3' is problematic.

This is almost the same for (4) and (B), and it is difficult to reduce the wobble in the horizontal direction.

In addition, the vertical fixation of the slider 3' and the slider mounting part 1' is due to the strangling of the protrusions 4' and 4'' of the slider mounting part, which are made of synthetic resin. There was a problem that the adhesion became weak over time and looseness occurred both horizontally and vertically.

Further, (4) has a complicated structure, and (B) has a simple structure but has the same problem as (C).

The present invention aims to improve the above-mentioned conventional drawbacks.

Furthermore, when the slider of the variable resistor is attached to the slider holder made of insulating plastic and the operating shaft, a locking claw on the slider base in the direction of the operating shaft is locked to the side surface of the operating shaft. be.

for example, Actual Publication No. 40-24274 Jitsukō 50-1050 Utility Model No. 50-113837 This is the idea described in et al.

However, although each of these ideas has a configuration that is convenient for assembly, the load bearing capacity of the contact portion of the slider is inherently weak, and the slider tends to float or fall due to pressure on the contact portion. In that case, the slider will completely fail.

For this reason, the above-mentioned drawbacks have been prevented by increasing the diameter of the shaft and increasing the number of pawls, or by increasing the thickness of the slider.

However, as the variable resistor becomes smaller, the diameter of the shaft becomes smaller, and the thickness of the slider must be thinner for the same contact pressure, but the contact pressure cannot be made much smaller due to performance reasons. The drawbacks of the above structure were even more severe.

In addition to the above-mentioned purpose, the present invention aims to improve the above-mentioned drawbacks of the conventional slider mounting structure by using a method in which a locking pawl provided in the shaft direction is locked to the side surface of the shaft. be.

Therefore, in the present invention, a locking pawl is also provided on the opposite side of the shaft, and this is inserted and locked into the side engagement hole of the slider holder of the shaft, and the positioning hole of the slider base and the shaft By force-fitting the engaging protrusion of the slider holder in both vertical and horizontal directions, the positioning of the sliding contact is accurate, and there is no play between the slider and the slider holder of the shaft. This is what I did.

Embodiments of the present invention will be described below with reference to the drawings.

Figures 1 to 6 show embodiments of the present invention. Figure 1 is a perspective view of the main part of the rotating shaft equipped with a slider, Figure 2 is a sectional view of the main part, and Figure 3 is the invention of the invention. FIG. 4A and FIG. 4B are a plan view of the slider, a perspective view with a part of the contact piece removed for convenience of explanation, FIG. 5A and FIG. 5B is a plan view, a side sectional view, and a perspective view of the rotating shaft, and FIG. 6 is a sectional view when it is installed.

FIGS. 7 and 8 show examples of conventional slider mounting structures.

FIG. 9 shows a resistor board related to the present invention, and FIG. 10 shows a switch board related to the present invention.

In FIGS. 1 to 6 showing an embodiment of the present invention, the slider 3 made of a metal spring plate is attached to a movable body (in this embodiment, a variable resistor) that is attached and held as shown in FIGS. 4A and 4B. In order to prevent the slider from floating when attached to the disc-shaped slider attachment part 48) on the upper part of the rotating shaft 4, the half-moon-shaped slider base 3A has a rear part in the left direction as shown in FIG. 4A. A protrusion 31 is provided in the center of the shaft in a direction opposite to the shaft center direction, and
A pair of alignment holes 32, 32 are provided in the base 3A.

In addition, in order to press-fit and lock the slider, a locking pawl 33 is projected forward in the right direction toward the center of the shaft on the center line of the slider base on the opposite side of the protruding portion 31, and on both sides thereof, as will be described later. A pair of sliding contact pieces 34, 34 that slide into contact with the ring-shaped current collecting electrode 24 of the resistance substrate 2 are protruded.

A resistor sliding contact piece 35 having a plurality of contact pieces on the outside of one of the sliding contact pieces 34 and slidingly contacting the resistor of the resistor board 2 is similarly projected forward.

The locking pawl 33 and sliding contact pieces 34 and 35 are each bent diagonally upward near the slider base 3A.

Here, the locking pawl 33 has a length such that it slightly contacts the side surface of a cylindrical shaft 44 protruding from the center of the end surface of the slider attachment portion 48 of the rotating shaft 4, which will be described later. It bites into the side surface of the cylindrical shaft 44 and is fixed.

Here, the position of the contact portion at the right tip of the resistor sliding contact piece 35 and the position of the contact portion at the tip of the pair of sliding contact pieces 34 that slide into contact with the current collecting electrode 24 of the resistor board 2 are different from those of the conventional variable resistor. It is provided on a line passing through the center hole of the resistor board 2 facing the resistor board 2 in the same way as the resistor.

Therefore, as shown in FIG. 4A, the outer shape of the slider 3 is in a semicircular shape S, and the upper end of the slider base 3A is unnecessary on the side opposite to the resistor sliding contact piece 35, so it is cut off. Therefore, the external shape of the slider 3 is small, the material yield in the press operation is good, and the material cost of the relatively expensive elastic slider plate is extremely low.

A rotating shaft 4 made of a molded product such as plastic is a first
As shown in Figures 49 and 5A, and Figure 5B, it consists of a small-diameter operating shaft part 49 and a large-diameter disc-shaped slider mounting part 48. , a cylindrical shaft 44 is provided which is co-centered with a concave portion 48A that engages with the half-moon-shaped base 3A of the slider 3 and an operating shaft portion 49 that projects in the center.

The tip of the cylindrical shaft 44 is provided with a small diameter portion 44A that rotationally fits into the center hole of the resistor substrate 2.

The concave portion 48A on the end surface of the slider mounting portion 48 has a protrusion 42.42 that engages with the alignment hole 32.32 of the slider 3, and a rear side surface that engages with the protrusion 31 at the rear of the slider 3. The provided receiver is provided with a hole 41 in the peripheral wall 46 of which engages a peripheral portion 36 of the slider 3 adjacent to said projection 31 .

Here, it is preferable that the protruding part 31 of the slider 3 has no play in the vertical direction with respect to the hole 41, and as shown in the opening of FIG. It is preferable that the right side, that is, the lower side, be cut out.

When the present invention is applied to a variable resistor, a resistor substrate 2 made of a phenol laminate or the like as an insulator includes a horseshoe-shaped carbon resin resistor 25 as shown in FIG.
Terminals 26 and 26 made of metal plates are fixed at both ends, and a terminal 26' is fixed at the center via a conductive current collecting electrode 24 and a conductive path.

Further, in the center of the resistor board 2, there is a cylindrical shaft 44 of the shaft 4.
A central hole 22 that engages with the small diameter portion 44A of the tip is provided.

FIG. 10 shows an embodiment of a switch board in which the present invention is applied to a switch instead of a variable resistor.A set of ring-shaped electrodes is mounted on a switch board 12' made of a phenol laminate or the like as an insulator. Terminals 26 and 26 made of metal plates are fixed to both ends of 25' and 25', and a terminal 26' is fixed to the center via a conductive current collecting electrode 24 and a conductive path.

Further, a central hole 22' is provided in the center of the switch board 12', which engages with the small diameter portion 44A of the cylindrical shaft 44 of the shaft 4.

Next, the process of attaching the slider 3 to the rotating shaft 4 will be explained with reference to FIGS. 4 to 6.

The base 3A of the slider 3 is connected to the slider mounting portion 4 of the rotating shaft 4.
8, insert the protrusion 31 of the slider into the hole 41 on the side of the recess 48A, and insert the alignment holes 32 and 32 of the slider 3 into the rotating shaft recess 48.
It is inserted into and engaged with the protrusion 42.42 of A.

Next, as shown in FIG. 2, when the locking pawl 33 protruding from the slider base 3A of the slider 3 is pushed down as shown by arrow a, the tip of the locking pawl 33 is attached to the rotating shaft 4. Cylindrical shaft 44
It digs in and locks into place.

Although the above work may be performed using a special tool, it is also easily possible to perform all the work with your fingers or tweezers.

Further, it is preferable that the locking pawl 33 has a tapered tip or a partially tapered portion near the tip.

In this case, when the locking pawl 33 of the slider 3 is pressed in the direction of arrow a in FIG. axis 44
It is easily press-fitted and locked.

Here, the slider 3 is made of a metal spring, and the locking claw 3
3 is bent upward and is locked to the cylindrical shaft 44 of the shaft 4, so that the half-moon-shaped base 3A of the slider 3 is in close contact with the upper surface of the slider mounting portion 48 of the shaft 4 in the vertical direction, and In the horizontal direction, the slider 3 is pushed towards the left side in FIG.
The holes 32, 32 at the base of the holder are pressed tightly in the right direction.

Here, after the slider 3 is temporarily fixed to the rotating shaft 4, the engagement protrusion 42 of the shaft may be bonded by thermocompression.

This further improves the adhesion of the slider. Since the present invention is constructed as described above, there is almost no need for any jigs during the installation work. After aligning the slider on the shaft with your fingers or tweezers, the slider can be installed by simply pressing the slider with your fingers or tweezers. Since the mover is attached and fixed to the movable body, the work is easy and highly practical.

In addition, the locking claw 33 for press-fitting the slider has a tapered tip, so it can be pressed with a small amount of force, and after installation, the slider is made of a metal spring material, so it will slide due to the restoring force of the spring. The child is firmly attached so that it does not come off easily.

Since the locking claw 33 of the slider 3 is bent diagonally upward and locked, the slider 3 closely contacts the upper surface of the slider mounting portion 48 of the shaft 4 in the vertical direction, and the locking claw 33 of the slider mounting portion 48A is in close contact with the upper surface of the slider mounting portion 48A of the shaft 4. Coating protrusion 4
2, the engagement hole 32 at the base of the slider 3 is tightly fixed with force without any wobbling in the horizontal direction. Automatically accurately positioned and fixed in both vertical directions.

In conventional fixing between the slider and the slider mounting part, the fixing force in the vertical direction often changes to some extent due to temperature/humidity cycles, age, etc., but in the present invention, the locking cylindrical shaft 44 has a large cross section and is strong. The locking pawl 33 of the slider is locked diagonally upward and locked with a constant elastic force S in both vertical and horizontal directions, so vertical and horizontal positioning is accurate and fixed. Excellent reliability.

The slider 3 has a small external shape, and the material cost of the elastic slider plate, which has relatively high loss, can be reduced.

Since the slider 3 receives the contact pressure of the sliding contact pieces 34 and 35 through the hole 41 of the rotary shaft 4 that engages the protrusion 31 at the rear of the slider, the withstand pressure is large and different from the normal one. In addition to the slider contact pressure, the contact pressure is increased to improve contact reliability for semi-fixed applications, and the slider can be used without failure.

[Brief explanation of drawings]

Figures 1 to 6 show embodiments of the present invention. Figure 1 is a perspective view of the main part of the rotating shaft equipped with a slider, Figure 2 is a sectional view of the main part, and Figure 3 is the invention of the invention. 4A and 4B are a plan view of the slider, a perspective view with a part of the contact piece removed for convenience of explanation, and FIG. 5A and FIG. 5B is a plan view, a side sectional view, and a perspective view of the rotating shaft, and FIG. 6 is a sectional view when it is installed. FIGS. 7 and 8 show examples of conventional slider mounting structures. FIG. 9 shows a resistor board related to the present invention, and FIG. 10 shows a switch board related to the present invention. 1: Earth plate, 2: Resistor board, 3: Slider, 4: Rotating shaft, 5: Click spring, 6: Case, 24: Current collector electrode, 25: Resistor, 31: Protrusion, 32: Position Aligning hole, 33: Locking claw, 34: Current collector electrode contact piece, 35: Resistor contact piece, 41: Projection receiver is hole, 42: Positioning projection, 44: Cylindrical shape that also serves as slider locking protrusion axis, 48:
Slider mounting portion, 48A: recessed portion, 49: operating shaft portion.

Claims (1)

[Claims for Utility Model Registration] A slider mechanism has a slider mechanism in which a slider made of an elastic metal plate is attached to a disc-shaped slider mounting part provided on the upper part of a rotary operation shaft made of insulating plastic. In electronic components, the base 3A of the slider 3 is provided with an alignment hole 32 that engages with the alignment protrusion 42 on the top surface of the slider mounting portion 48 of the operating shaft, In the direction toward the upward protruding shaft 44 concentric with the operation shaft 4 provided on the mover mounting portion 48, there are elastic contact pieces 34, 35, and a slider base 3A near the slider base 3A that engages with the side surface of the protruding shaft 44. The elastic locking claw 33 bent upward at the slider base 3A is
A protrusion 31 is provided in the opposite direction, and a lock receiving hole 41 that engages with the protrusion 31 of the slider is provided on the side surface of the peripheral portion of the slider mounting portion 48 of the operating shaft 4. While attaching the slider 3 to the upper surface of the slider mounting portion 48 of the operation shaft, the elastic locking pawl 33 of the slider base 3A
is pressed against the projection shaft 44 from above and bent diagonally upward to lock it, and the slider base 3A of the slider 3 is perpendicular to the slider mounting surface of the slider mounting portion 48 of the shaft 4. A slider mounting structure for small electronic components characterized by a horizontally biased and tightly fixed structure.