JPS638038Y2 - - Google Patents

Description

[Detailed description of the invention] This invention is designed to maintain stable contact between the switch contacts even when a light force or vibration is applied to the operating shaft when the switch is closed. When combined, it is intended to provide a pull-push type switch in which the contact of the switch contacts is stable even if the shaft is rotated during operation of the variable resistor.

Figures 1 to 4 show the structure of this type of pull-pull switch combined with a rotary variable resistor operated on the same axis as previously proposed by the present inventors. This is a movable elastic contact piece made by bending an elastic leaf spring into a substantially U-shape, and the elastic contact piece 1 has a fixed contact 4 held between both legs 2 and 3 having a dogleg-shaped cross section. On the other hand, by vertically operating the operating shaft 9 equipped with a driving piece 8 made of an insulating material and having a large diameter part 6 and a small diameter part 7 arranged on the same central axis via an intermediate large diameter protrusion 5, the operating shaft When 9 is pressed (lowered), the first
As shown in the drawings and FIG. 2, the large diameter portion 6 of the drive piece 8 pushes open both leg portions 2, 3 of the movable elastic contact piece 1, and the switch terminals 10, 11 are connected to the movable elastic contact piece 1 and the fixed contact 4. (11 is not shown) is open,
When the operating shaft 9 is pulled (raised), the small diameter portion 7 of the drive piece 8 is located between the legs 2 and 3 of the movable elastic contact piece 1, as shown in FIG. 2 and 3 are in a state where the fixed contact 4 is sandwiched between them, and the switch terminals 10 and 11 are closed.

In this case, both legs 2 and 3 of the movable elastic contact piece 1 are in contact with the fixed contact 4 at almost the same position with respect to the vertical movement direction of the operating shaft 9 (drive piece 8), so when the switch is closed, the operating shaft When light vibrations, shocks, etc. are applied to the switch 9, the legs 2 and 3 are pushed apart by the large-diameter protrusion 5 of the drive piece 8, which tends to make the contact of the switch unstable, especially as shown in FIGS. 1 and 3. As shown in Figure 2, when combined with a rotary variable resistor, a slight vertical force is often applied when the variable resistor is rotated, which is a drawback of this type of switch.

In addition, as shown in FIG. 5, the tapered portions 2' and 3' of both leg portions 2 and 3 of the movable elastic contact piece 1 of the switch having a dogleg-shaped cross section, and the tapered portion of the intermediate large diameter protrusion 5 of the drive piece 8. In some cases, a small gap g may be provided between the
In this case, there is a drawback that the operating shaft 9 has play in the vertical direction, which is a factor that deteriorates the quality of the switch.

Further, in FIGS. 1 to 5, 12 is a bearing, 13 is a mounting board on which a resistor 14 is mounted, and 15 is a brush mounting body mounted on the operating shaft 1 so as to rotate together with the operating shaft 1. A brush 16 whose tip slides on the resistor 14 by rotating the operating shaft 9 is fixed to the brush mounting body 15, and the brush 16 is in constant contact with the mounting board 13. A contactor 17 is attached by a middle terminal 18. 19
is the variable resistor cover, 20 is the switch cover, 2
1 is an insulating cover provided inside the switch cover 20, and 22 is a mounting board on which the switch terminals 10 and 11 are attached.

This invention was devised to solve the above problems, and its specific configuration is described in the sixth section below.
The description will be given with the same numbers assigned to the same parts as above in conjunction with FIGS.

6 and 7 show an embodiment of the present invention,
FIG. 6 shows the switch in a closed state, and FIG. 7 shows the switch in an open state. In the present invention, both legs 2 and 3 of the movable elastic contact piece 1 are located such that the apex position of one leg 2 is shifted from the apex position of the other leg 3 by an amount a toward the variable resistor. The apex positions of parts 2 and 3 are slightly shifted vertically. The apex portion of the leg portion 2 is in contact with the small diameter portion 7 of the drive piece 8 in the closed state, and in this state, the apex portion of the leg portion 3 is in contact with the fixed contact 4 with appropriate pressure. The shift amount a of the apex positions of both legs 2 and 3 is such that when the switch is closed (operating shaft 9 is pulled) as shown in FIG. When the switch is in the open state shown in the figure (the operating shaft 9 is pressed), the leg 3 is in contact with the large diameter portion 6 of the drive piece 8 in the same way as the leg 2, and the switch is connected to the operating shaft 9 in either the closed or open state. Set the value to a value that does not cause wobbling even under these conditions.

Next, regarding other embodiments of the present invention, only the relationships among the three parts of the movable elastic contact piece 1, the fixed contact 4, and the drive piece 8 are shown in FIGS. 8 to 11, and FIGS.
The figure shows the switch in the closed state, and FIGS. 9 and 11 show the switch in the open state.

First, in the embodiments shown in FIGS. 8 and 9, the leg 2 of the movable elastic contact piece 1 is also in contact with the fixed contact 4 in the same way as the leg 3 when the switch is closed. In addition, in the embodiments shown in FIGS. 6 and 7 above, especially when the operating shaft 9 is pressed (switch open), the leg portion 3 of the movable elastic contact piece 1 and the driving piece 8 are in contact with each other at their tapered portions. In some cases, the insulating gap between the leg portion 3 and the fixed contact 4 may vary slightly due to variations in the stroke of the operating shaft 9. However, as shown in FIGS. The cross-sectional shape of the leg 3 that contacts the fixed contact 4 on the side of the small diameter portion 7 is the portion below the dogleg-shaped apex as the drive piece 8.
By making the shape parallel to the vertical movement direction of the operating shaft (and the operating shaft 9), it is possible to maintain a large gap between the leg portion 3 of the movable elastic contact piece 1 and the fixed contact 4 when the switch is open, and also maintain a large gap between the operating shaft and the fixed contact 4. No fluctuations occur due to variations in the strokes of No. 9. In addition, in this case, the contact area in the closed state of the switch also becomes large, and the contact becomes stable.

In addition, in the above embodiment, the case was described in which the variable resistor is combined with a rotary variable resistor, but the present invention is also stable when used as a variable resistor with a dual switch, which is also combined with a rotary switch, as shown in Fig. 12. Of course, a contact pull/push type switch is obtained. In addition, in the above embodiment, the switch is opened by the push operation, and the switch is closed by the pull operation, but the pull/push type switch of the present invention reverses the positional relationship between the large diameter part and the small diameter part of the drive piece. Of course, it can also be applied to the opposite type.

The present invention is constructed as described above, and the roles of both legs of the movable elastic contact piece are shared with the electric contact and the moderation part, so even when slight vibrations or shocks are applied to the operating shaft, the switch state remains stable. Moreover, it is possible to realize a high-quality pull-push type switch with no vertical play on the operating shaft.

[Brief explanation of drawings]

Fig. 1 is a side cross-sectional view showing the closed state of the pull-push type switch proposed earlier by the present inventors in combination with a variable resistor, and Fig. 2 is a top view of the main parts of the switch in the closed state. Fig. 3 is a side sectional view showing the switch in an open state, Fig. 4 is a perspective view of a movable elastic contact piece constituting the switch, and Fig. 5 is a side sectional view showing a modification of Figs. 1 to 4. 6 is a side sectional view of a pull-push type switch according to the present invention in combination with a rotary variable resistor when the switch is in a closed state, and FIG. 7 is a side sectional view of the main part of the switch when it is in an open state. 8 and 10 are side sectional views of main parts of the switch in the closed state in other embodiments of the present invention, and FIGS. 9 and 11 are views of the switch corresponding to FIGS. 8 and 10, respectively. FIG. 12 is a side sectional view of a main part in an open state, and FIG. 12 is a side sectional view of a variable resistor with a double switch in still another embodiment of the present invention. 1...Movable elastic contact piece, 2, 3...Both legs, 4...
...Fixed contact, 5...Large diameter protrusion, 6...Large diameter part, 7
...Small diameter section, 8...Drive piece, 9...Operation shaft.

Claims (1)

[Claims for Utility Model Registration] (1) A contact in which a fixed contact is arranged between the vertices of both legs formed in a dogleg-shaped cross section of a movable elastic contact piece made by bending an elastic plate spring into a substantially U-shape. The apex positions of both of the legs are slightly shifted vertically, and the drive piece made of an insulating material having a large diameter part and a small diameter part on the same central axis is connected to the drive piece as described above through an intermediate large diameter protrusion. The movable elastic contact piece is mounted on an operating shaft so as to be located between both legs of the movable elastic contact piece, and as the operating shaft moves up and down, the large diameter part of the drive piece pushes open both legs of the movable elastic contact piece, and the contact opens. A pull-push type switch configured to be closed when the small diameter portion of the drive piece is located between both legs of the movable elastic contact piece. (2) The pull-push type switch according to claim 1, which is registered as a utility model and has a structure in which one of the legs of the movable elastic contact piece does not contact the fixed contact even when the contact is closed, but contacts the small diameter part of the drive piece. . (3) Of both legs of the movable elastic contact piece, the cross-sectional shape of the leg that contacts the fixed contact on the small diameter side of the drive piece is such that the part on the side that contacts the fixed contact from the apex of the dogleg shape is A pull-push type switch according to claim 2 of the utility model registration claim, which has a shape parallel to the vertical movement direction.