JPS5826484Y2 - variable resistor - Google Patents

Description

[Detailed explanation of the idea] This invention relates to improvement of a variable resistor.

As shown in FIGS. 1 and 2, a variable resistor that has been put into practical use has a resistor 1a on the top surface,
- Rotatably fit the head caulking screw 3 into the center hole 2 of the resistor board 1 with the three terminals a, l) from below through the two terminals C, and attach the slider to the tip of the caulking screw 3. 4 and the mounting bracket 5 after engaging the rising edge 4a and the groove 5a, and inserting the rising edges 5b, 5b of the case mounting bracket 5 into the insertion grooves 5a, 5a of the dust-proof case 6, and tightening the resistance. Assemble the caulking screw 3, slider 4, case mounting bracket 5, and dustproof case 6 integrally to the board 1, and rotate the slider 4 from the screwdriver groove 3a of the head screw 3 or the driver groove 6b of the dustproof case 6. I try to do that.

However, with the above configuration, the electrical continuity between the slider 4 and the head crimping screw 3 depends on the crimping strength of the case mounting bracket 5, resulting in variations in contact resistance, and the rotating torque varies depending on the strength of crimping. Not only did this result in unstable product quality, such as changes in values, but it also required a part called a case mounting bracket.

This invention was made to solve the above-mentioned conventional drawbacks, and each part can be easily and quickly attached without crimping.
Furthermore, the present invention provides a new variable resistor that can be assembled reliably without any variation in quality, and that can omit case mounting fittings.

Hereinafter, embodiments of this invention will be described in detail with reference to the accompanying drawings.

As shown in FIGS. 3 and 4, the variable resistor includes a metal headed shaft 11, two terminals 12, and a resistance board 13.
, a metal slider 14, and a synthetic resin dustproof case 15.

The headed shaft 11 has an axial knurling formed on the entire circumference of the shaft portion 16, and the knurling constitutes engagement grooves having a constant pitch with respect to the outer circumferential contour.

The two terminals 12 are connected to the shaft portion 1 of the headed shaft 11 in the center.
The terminal 1 has a hole 12a through which the terminal 6 is inserted, and has a terminal 1 hanging down on both sides.
2b and the raised locking piece 12C, 7L12
The area near a is slightly curved in advance to give it springiness and improve contact with the headed shaft 11.

The resistance board 13 has a center hole 17 in the center through which the shaft 16 of the headed shaft 11 is inserted, and a roughly semicircular resistor 18 is pasted on the upper surface, and the resistor 18 is attached downward from both ends thereof. In addition to providing extending 1-3 terminals 19a and 19b, the above 2
A groove 20 is provided in which the locking piece 12C of the terminal 12 engages,
2 terminal 12 is held in a non-rotatable manner.

The slider 14 has a retaining hole 21 in the center thereof in which the knurling of the shaft portion 16 of the headed shaft 11 engages, and the engaging hole 21 has an equal pitch with respect to the knurling constituting the engaging groove. It constitutes an engaging protrusion.

One side of the slider 14 is provided with a sliding contact piece 22 that slides on the resistor 18, and the other side is provided with a rising portion 23.

The resistance board 1 is placed around the engagement hole 21 of the slider 14.
An annular protrusion 24 protruding toward the third side is provided, and the protrusion 24
is brought into contact with the resistance board 13, and the slider 14
This is to reduce friction between the resistor board 13 and the resistor board 13, and to eliminate torque unevenness during rotation.

The dust-proof case 15 has a press-fit hole 25 in the center of the lower surface of the canopy 15 a into which the shaft portion 16 of the headed shaft 11 is press-fitted, and an insertion groove 26 on the side thereof into which the rising edge 23 of the slider 14 is inserted. It is set up.

Note that 11a is a driver groove provided in the head of the headed shaft 11, and 15b is a driver groove provided in the center of the upper surface of the canopy 15a of the dustproof case 15.

To assemble the variable resistor with the above configuration, first,
The shaft part 16 of the headed shaft 11 is inserted into the hole 12 of the two terminals 12.
a, and rotatably fit into the center hole 17 of the resistance board 13 from below, engage the locking piece 12C of the two terminals 12 with the groove 20 of the resistance board 13, and then connect the two terminals 12 to the resistance board. 13
It is held so that it cannot rotate freely.

Next, insert the engagement hole 21 of the slider 14 into the resistance board 13.
The slider 14 is fitted into the shaft portion 16 of the headed shaft 11 from above to hold the slider 14 non-rotatably with respect to the headed shaft 11.

Next, insert the press-fit hole 25 of the dustproof case 15 into the head shaft 1.
At the same time, insert the insertion groove 26 into the rising edge 23 of the slider 14 and attach the dustproof case 15.
is held on the headed shaft 11 so as to be non-removable and non-rotatable.

Therefore, for the two integrated terminals 12 and the resistor board 13,
Headed shaft 11. Slider 14 and dustproof case 1
5 is integrally assembled so as to be rotatable.

The variable resistor assembled in this way has a head attached to the shaft 11.
By inserting a screwdriver into the screwdriver groove 11a or the screwdriver groove 15b of the dustproof case 15 and turning it,
When the slider 14 rotates, the sliding contact piece 2 against the resistor 18
By changing the position of 2, the resistance value can be changed.

The locking structure between the sliver 14 and the dustproof case 15 is as follows:
The rising edge 23 of the slider 14 is inserted into the insertion groove 26 of the dustproof case 15, but as shown in FIGS. It may also be a locking structure in which the projection pin 31 is fitted.

As is clear from the above description, according to the present invention, the following effects can be obtained.

■Since the thin protrusion of the engagement hole of the metal slider is press-fitted into the retaining groove of the knurl of the metal headed shaft, conduction between the slider and the two terminals can be ensured through the metal headed shaft. Ru.

■As the headed shaft is provided with equally pitched knurled engagement grooves and the slider engagement hole is provided with equally pitched thin protrusions, there is no particular positional relationship between the headed shaft and the slider, and the slider can be press-fitted. In this case, even if the headed shaft rotates, the press-fitting operation can be performed in that state, which facilitates mass production on an assembly line.

■Both the headed shaft and slider are made of metal, so
Since there is no loosening (of the press-fit part) due to heat, the conduction from the slider to the two terminals is reliable, and the slider does not wobble, making it electrically stable.

■Since the shaft of the shaft with a head is knurled, the dustproof case can be press-fitted onto the shaft at the same time as the slider, so the rotating torque can be maintained constant simply by press-fitting using caulking, etc. The whole variable resistor can be assembled well, and a variable resistor that is suitable for mass production can be obtained.

[Brief explanation of the drawing]

Figure 1 is an exploded perspective view of a conventional variable resistor, and Figure 2 is an exploded perspective view of a conventional variable resistor.
3 is an exploded perspective view of the variable resistor according to this invention, FIG. 4 is an assembled sectional view of the variable resistor shown in FIG. 3, and FIG. 5 is an assembled sectional view of the variable resistor according to this invention. FIG. 6 is an exploded perspective view of essential parts showing another example of a variable resistor, and FIG. 6 is an assembled sectional view of the variable resistor shown in FIG. 11...Shaft with head, 13...Resistance board, 14...Slider, 15...
Dustproof case, 16...shaft, 17...
Center hole, 21...Engagement hole, 24...Protrusion, 25...Press-fit hole, 26...Insertion groove, 30... ...Notch, 31...Protrusion pin.

Claims (1)

[Scope of utility model registration request] A metal headed shaft with fine axial knurling engagement grooves arranged at equal pitches around the entire circumference of the shaft, a resistance board with a resistor on the top surface, and a knurled engagement groove on the shaft. A metal slider provided with a retaining hole in which fine engaging projections are formed at an equal pitch, and a locking part, a press-fit hole into which the shaft part is press-fitted, and a locking part which locks the locking part. and a synthetic resin type dustproof case provided with a synthetic resin type dustproof case, the shaft portion of the headed shaft is rotatably fitted from below into the center hole of the resistor board, and the engagement hole of the slider is fitted into the center hole of the resistor board. The board is fitted into the shaft part from above so as not to rotate freely, and at the same time, the press-fit hole of the dustproof case is press-fitted into the tip of the shaft part, and at the same time, the locking part is locked with the locking part of the slider. , a variable resistor characterized by integrally assembling a shaft with a head, a slider, and a dustproof case on a resistor board.