JPH0121530Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a variable resistor used in small consumer appliances and the like, and particularly to the structure of a slider piece that rotates and slides on a resistor and a current collector.

Recently, there has been a growing trend towards ultra-compact and ultra-thin consumer equipment such as radios and tape recorders. There is also a growing demand for resistors that are extremely small and of a multiple type.

The present invention meets the above requirements.

Next, embodiments of the present invention will be described in detail with reference to the drawings.

The drawings are all related to the present invention, and FIG. 1 is a perspective view showing a small rotary variable resistor, FIG. 2 is an exploded perspective view of the same, and FIG. 3 is a sectional side view of the same. In the figure, 1
1 is a mounting plate made of a single metal material, and the mounting plate 1 is formed with a plate body 1a, a shaft hole 1b, and bent pieces 1c and 1d. 2 and 7 are insulating substrates on which resistors 9, current collectors 11, etc., which will be described later, are formed by printing, and the insulating substrates 2 and 7 have shaft holes 2b and 7b and recesses 2c and 7c. Terminals 3, 8 are attached to each end by eyelets 3a, 8a. Note that the terminals 3 and 8 are shaft holes 2b, into which shaft portions 4a, 4d of a slider receiver 4, which will be described later, are inserted.
7b, the terminal 3 is located at the surface of the first insulating substrate 2 on which the resistor and the current collector (both not shown) are formed, and the terminal 8 is located at the second The resistors 9 and the current collectors 11 are respectively led out to the outside (downward in FIG. 2) from a surface of the insulating substrate 7 that is different from the surface on which the resistor 9 and the current collector 11 are formed. Reference numeral 4 denotes a slider receiver made of molded resin, and the slider receiver 4 includes shaft portions 4a, 4d, a receiving portion 4c, and a slider piece 5.
The receiving portion 4c includes a projection 4e for holding the lock and a projection 4f serving as a stopper for regulating rotation.
are formed at each end of the Note that a cutting portion 4b is formed at the end of the shaft portion 4a.
5 is a slider piece made of a metal plate, and the slider piece 5 has a plate portion 5a, a mounting hole 5b for engaging with the projection 4e, and outer and inner sliders 5c. ,5e
is formed. Note that the slider 5e is connected to the plate portion 5a by a bent connection portion 5d. Reference numeral 6 denotes an annular case made of molded resin, and the case 6 includes a wall portion 6a, pillars 6b and 6d,
A convex portion 6c for a stopper is formed. Note that the convex portion 6c is not arranged parallel to the wall portion 6a but slightly inclined. Also, the pillar 6b
is formed longer than the support column 6d.

To explain the assembly and operation of the variable resistor configured as described above, first, the resistor 9 is placed on the surface.
An annular case 6 is placed on a second insulating substrate 7 on which a current collector 11, terminal connection electrodes 10, 10, 12, etc. are formed. At this time, the elongated support column 6b of the case 6 is locked by the recess 7c of the insulating substrate 7, and positioning is performed. and slider piece 5
One shaft portion 4d of the slider receiver 4 to which is fixed is inserted into the shaft hole 7b, and the other shaft portion 4a is inserted into the shaft hole 2b of the first insulating substrate 2. At this time, the insulating substrate 2
The support column 6b of the case 6 is locked in the recess 2c in the same manner as described above. After this, insert the shaft hole 1b of the mounting plate 1 into the shaft part 4.
A bent piece 1c inserted through a and extending to the side of the case 6
is bent below the second insulating substrate 7, and the first and second insulating substrates 2, 7, the case 6, and the slider receiver 4 are locked and integrated. Incidentally, the bent piece 1c is arranged and positioned so as to be sandwiched between the pillars 6b of the case 6, as shown in FIG.

4a, b and 5a, b are diagrams for explaining the process of forming electrodes on an insulating substrate. First, the terminals are connected to the current collector 11 by printing or the like on the second insulating substrate 7. Electrodes 10, 10, 12 are formed from silver paste. This silver paste is made of a material with good anti-sliding properties. Next, the resistor 9 is formed by printing the carbon resistor so that a portion of both ends thereof overlap the terminal connection electrodes 10, 10. Next, the terminal connecting electrodes 10, 10, 12 are covered with a flexible silver paste, such as a silver paste containing fine conductive rubber powder, on the part where the eyelet 8a of the terminal 8 is located. ', 10', 12' are formed.
The flexible silver paste may also be formed by applying a temperature lower than the curing temperature to a silver paste based on a thermosetting resin so as to be in a semi-cured state.

As described above, the electrode of the portion of the terminal 8 that fits into the eyelet 8a has a two-layer structure of a silver paste having sliding resistance (wear resistance) and a flexible silver paste. As a result, when the terminal 8 is attached to the second insulating substrate 7 as shown in FIG. 6, the eyelet 8a's eyelet 8a' is embedded into the flexible silver paste 12', increasing the bonding strength. You can get enough. This is particularly effective for use in parts where a sufficient area cannot be taken up, such as in the case of an ultra-small variable resistor with an outer diameter of 8 mm, as in the present case. Furthermore, when the terminal 8 is soldered, the two-layer structure also has the effect of improving heat resistance.

FIG. 7 is a perspective view showing the slider piece 5. As is clear from the figure, the slider piece 5 includes a plate portion 5a having a mounting hole 5b, and a plate portion 5a that is continuous with the plate portion 5a and has a central portion. An annular connecting portion 5g having an axial hole 5f at one end, an outer slider 5c bent at an acute angle at one end of the plate portion 5a, and an outer peripheral edge of the connecting portion 5g. It has an inner slider 5e which is folded back via a bent connection part 5d, and these are made of a single elastic metal plate such as nickel silver or the like. The shaft hole 5f is inserted through the shaft portion 4a or 4d of the slider receiver 4, and the mounting hole 5b is inserted through the projection 4e, and by thermally melting the projection 4e, The slider piece 5 is fixed to the slider receiver 4.

When the slider receiver 4 is rotated, the outer slider 5c is connected to the terminal connection electrode 1 of the insulating substrate 2 or 7.
0 and the resistor 9, while the inner slider 5e is located on the connecting portion 5g at a predetermined interval and rotates and slides on the conductor 11. The resistance value changes depending on the displacement of the elements 5c and 5e.
In this case, the reaction force generated by the outer slider 5c coming into elastic contact with the insulating substrate acts on the fixed part of the slider piece 5 (the caulked portion of the protrusion 4e and the mounting hole 5b), but The reaction force generated when the slider 5e comes into elastic contact with the insulating substrate is the bending connection portion 5d.
(the folded part) and not the fixed part, and furthermore, these two points of action (the mounting hole 5b and the bending connection part 5d) are distributed at approximately 180 degrees opposite positions via the shaft hole 5f. , the slider piece 5 is the slider receiver 4
is fixed with high strength.

FIGS. 8a and 8b are a plan view and a front view of the slider receiver. The slider receiver 4 is made of molded resin such as polyacetal, and has shaft portions 4a and 4d and an end portion of the shaft portion 4a. A pair of flat portions 4b formed in
and a receiving portion 4c on which the slider piece 5 is placed.
A protrusion 4e for attaching the slider piece 5, and a pair of protrusions 4f, 4f for a stopper for restricting the rotation of the slider receiver 4 by coming into contact with a convex portion 6c formed on the case 6. and an engaging portion 4g into which the shaft hole 5f of the slider piece 5 is inserted and locked.
Note that the protrusion 4e has a conical portion 4h at the tip and a receiving portion 4.
c and two continuous protrusions 4i, 4i.

FIG. 9 is a side view showing how the slider piece is attached to the slider receiver.

The respective shaft holes 5f of the pair of slider pieces 5 are inserted into the shaft portions 4a and 4d of the slider receiver 4, and the receiving portion 4c is inserted so that the mounting hole 5b is inserted into the protrusion 4e.
Place the slider piece 5 on top. As a result, each slider piece 5 is positioned relative to the slider receiver 4. Further, by thermally melting the conical portion 4h of the protrusion 4e, the slider piece 5 is formed into the slider receiver 4.
It stays firmly in place without wobbling. At this time, since the tip of the protrusion 4e is formed into a conical shape, smooth insertion into the attachment hole 5b having a small diameter is achieved, and workability is improved. Further, by forming a plurality of protrusions 4i, the mounting hole 5b is reliably engaged with and held by the protrusion 4e, and the slider piece 5 is accurately positioned on the slider receiver 4.

By this fixing, the slider 5c of the slider piece 5
protrudes from one end of the receiving portion 4c, and the slider 5e is arranged with the shaft portions 4a and 4d therebetween, so that the sliders 5c and 5e can be elastically deformed without any problem.

FIG. 10 is a diagram for explaining the stopper mechanism, in which the stopper projection 4f formed on the slider receiver 4 and the convex portion 6c of the case 6 come into contact with each other, so that the slider Rotation of the receiver 4 is restricted. At this time, the projections 4f, 4f formed on the upper and lower opposing surfaces of the respective ends of the receiving part 4c.
The left and right rotations are respectively regulated by these. Note that, since the protrusion 6c of the case 6 is arranged at an angle with respect to the wall surface 6a, the protrusion 6c and the protrusion 4f do not come into contact with each other even though the variable resistor is miniaturized. A sufficient area can be obtained, and a sufficiently strong stopper mechanism can therefore be constructed.

As described above, according to the present invention, the outer slider is bent on the plate part that becomes the fixing part to the slider receiver, and the inner slider is bent on the annular connecting part continuous with the plate part. Since it is formed by folding back the slider, the reaction force when the outer and inner sliders come into elastic contact with the insulating substrate is not concentrated on the fixed part of the slider piece.
It can be dispersed using the folded part,
Therefore, even in the case of a small variable resistor with limited space for fixing, it is possible to prevent the slider piece from lifting up and improve reliability.

[Brief explanation of the drawing]

The drawings all relate to embodiments of the present invention and are
The figure is a perspective view of a small rotary variable resistor, Figure 2 is an exploded perspective view of the same, Figure 3 is a cross-sectional view of the same essential parts, Figures 4a, b and 5a, b are of an insulating substrate. A diagram for explaining the process of forming an electrode, FIG. 6 is a cross-sectional view of the main part showing a state in which a terminal is mounted on an insulating substrate, FIG. 7 is a perspective view showing a slider piece, and FIGS. 8 a and b 9 is a plan view and a front view showing the slider receiver, FIG. 9 is a side view showing the state in which the slider piece is attached to the slider receiver, and FIG.
The figure is a diagram for explaining the stopper mechanism. 1... Mounting plate, 2... First insulating board, 3, 8
...Terminal, 4...Slider receiver, 4e...Protrusion (fixed part), 4a, 4d...Shaft part, 5...Slider piece,
5c... Outer slider, 5d... Bent connection part, 5
e...inner slider, 6...case.

Claims (1)

[Scope of utility model registration request] The slider includes a slider receiver made of molded resin, a slider piece made of a metal plate fixed to the slider receiver, and an insulating substrate having a resistor and a conductor formed concentrically. In a variable resistor in which outer and inner sliders integrally formed on the mover piece rotate and slide on the resistor and conductor, respectively,
The slider piece is provided with a plate portion having a mounting hole and an annular connecting portion continuous with the plate portion, the outer slider is bent into the plate portion, and the inner slider is bent into the plate portion. A variable resistor characterized in that one slider is formed by folding back the outer peripheral edge of the connecting portion facing the mounting hole, and the mounting hole is inserted and fixed to a protrusion provided on the slider receiver. vessel.