JP3181492B2 - Switch device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an extremely small switch device which is mainly used for switching according to the operation of a movable member in a system and is also called a mechanical drive type.

[0002]

2. Description of the Related Art As a conventional switch device of this kind, the one shown in FIGS. In the conventional switch device shown in these figures, a first fixed contact terminal 1 and a clip-shaped second fixed contact terminal 2 are exposed inside a casing 3 molded into a box with a bottom. A torsion coil spring 5 having a wafer 4, a movable contact portion 5a capable of coming in contact with and separating from the second fixed contact terminal 2, and constantly contacting the first fixed contact terminal 1, and a driving portion of the torsion coil spring 5 A columnar slider 6 capable of pressing the wafer 5b toward the inner bottom surface of the wafer 4, and a guide hole 7 through which the slider 6 is inserted.
a and a case 7 for providing a guide wall 7b surrounding the guide hole 7a and closing the upper opening of the wafer 4. The wafer 4 is provided with a first
And external connection terminals 8 and 9 respectively derived from the second fixed contact terminals 1 and 2 are projected.

When manufacturing such a switch device, a hoop material 10 made of a highly conductive metal plate is subjected to press working or the like to thereby form a bridge having the first fixed contact terminal 1 and the external connection terminal 8. The second fixed contact terminal 2 is erected to form a bridged portion having an external connection terminal 9, and then the hoop material 10 is sent to a mold and molded to form a hoop material 10. A casing 3 having a predetermined shape supported and fixed is formed, and a wafer 4 which is an integrated product of the casing 3 and various terminals 1, 2, 8, 9 is obtained.
Here, the second fixed contact terminal 2 is formed by performing a predetermined press working on a tip band-shaped portion of a portion of the hoop material 10 expanded in a substantially T-shape. After folding both ends of the band-like portion into a substantially U-shape, a punch die is arranged at the center of the band-like portion and both sides are erected to obtain a clip-like fixed contact terminal 2 as shown in FIG. ing.

After the wafer 4 is formed,
A torsion coil spring 5 is incorporated in the wafer 4 at a predetermined position that is always in contact with the first fixed contact terminal 1. The torsion coil spring 5 has a substantially U-shaped portion extending from one end side of a winding portion 5c and the movable contact portion 5a which comes into contact with and separates from the driving portion 5b which contacts the slider 6 and the second fixed contact terminal 2. In addition, a fixed end portion 5d that is fixed on the first fixed contact terminal 1 in a press-contact state is protruded from the other end side of the winding portion 5c. Then, after the torsion coil spring 5 is housed in the wafer 4, the case 7 is arranged on the wafer 4 with the slider 6 inserted into the guide hole 7a, and the engagement of the wafer 4 with the locking hole 7c of the case 7 is performed. By snapping the projection 4a, the case 7 is mounted on the wafer 4 from above and the assembly is completed.

[0005] In the wafer 4 of the switch device thus assembled, the winding portion 5 of the torsion coil spring 5 is provided.
c is pressed down from above by a pressing projection 7d of the case 7, and the resilient force generated by the winding portion 5c causes the driving portion 5c to move.
b always urges the pressing portion 6a of the slider 6 upward. A guide groove 7e is formed in the case 7 near the holding protrusion 7d.
e, the movable contact portion 5a of the torsion coil spring 5 is loosely inserted in the vicinity of the movable contact portion 5a so that the movable contact portion 5a moving following the drive portion 5b does not fluctuate, ie, the drive portion 5b reaches a predetermined position. It is designed such that the movable contact portion 5a sometimes comes into contact with the clip-shaped fixed contact terminal 2 reliably.
Furthermore, a mounting hole 7f is formed in the case 7, and the switch device can be mounted on a panel or the like using the mounting hole 7f.

Next, the operation of the above-described conventional switch device will be briefly described. Now, assuming that no pushing operation force acts on the slider 6, as shown in FIG.
The slider 6 is pushed up to the uppermost point (initial position) by receiving the elastic force of the torsion coil spring 5, so that the movable contact portion 5 a of the torsion coil spring 5 moves upward from the clip-like fixed contact terminal 2. In the position, the fixed contact terminal 2 and the first fixed contact terminal 1 are not electrically connected, and the circuit is kept off.

However, when the slider 6 is pushed downward by a predetermined amount, the driving portion 5b of the torsion coil spring 5 is pushed downward by the pressing portion 6a of the slider 6, and the movable contact portion 5a is connected to the clip-like fixed contact terminal. 2 contacts the second contact portion 2a. That is, the movable contact portion 5a of the torsion coil spring 5 is press-fitted between the pair of contact portions 2a which are located at the center of the fixed contact terminal 2 and are in elastic contact with each other.
The first and second fixed contact terminals 1 and 2 are conducted through the torsion coil spring 5, and the circuit is turned on. Thereafter, when the pushing operation force on the slider 6 is removed, the slider 6 is again pushed up to the uppermost point by the resilient force of the torsion coil spring 5, and the movable contact portion 5
a moves upward away from the fixed contact terminal 2 in the form of a clip, and the circuit returns to the off state.

Therefore, if the above-described switch device is arranged near the movable member of the system and the slider 6 is set up and down with the movement of the movable member, the position of the movable member can be detected. Alternatively, a switch switching operation interlocked with the movable member can be performed. However, this type of switch device, which is also referred to as a mechanical drive type, is designed so that a target movable member in the system can reliably push the slider 6 in operation, and that the switch device does not adversely affect the arrangement of other members. Therefore, it is said that it is preferable to design the device very small.

[0009]

In recent years, there has been an increasing demand for a thinner switch device of this type, and attempts have been made to reduce the height of the wafer 4 as much as possible. As shown in FIGS.
Is formed by forming a bottom plate portion of the housing portion 3 on the back side (the lower side in the figure) of the metal plate using the hoop material 10 as a base material, and the bottom plate portion is formed of molten resin in a mold. Since a thickness that does not impede the flow is required, if a dimension equal to or more than the operation stroke is secured between the metal plate and the slider 6, there is naturally a limit to the reduction in thickness. That is, in order to avoid a decrease in reliability due to a variation in the relative position with respect to the movable member or the like, it is necessary to secure an appropriate operation stroke for the slider 6. It was structurally difficult to achieve the desired thickness reduction without sacrificing stroke.

[0010] The present invention has been made in view of such problems of the prior art, and an object of the present invention is to provide a switch device capable of achieving a desired thickness without sacrificing an operation stroke.

[0011]

An object of the present invention is to provide a wafer having a first fixed contact terminal and a clip-shaped second fixed contact terminal exposed inside, and a second fixed contact terminal. A torsion coil spring having a movable contact portion that can be brought into contact with and separated from the first fixed contact terminal, and a slider capable of pressing and driving a part of the torsion coil spring; In the switch device for moving the movable contact portion to and away from the second fixed contact terminal in accordance with the above, in a metal plate integrated with the bottom portion of the wafer, a portion facing the bottom surface of the slider is drawn. This is achieved by providing a recess formed as described above and exposing the bottom surface of the recess to the outside.

[0012]

If the wafer has the above-described structure, the portion of the bottom of the wafer facing the bottom of the slider has an inner bottom surface lower than the other portions and has a thickness corresponding to the thickness of the metal plate. In addition, since a bottom plate made of synthetic resin having a thickness that does not hinder the flow of the molten resin can be formed around the recess, the wafer can be thinned while securing a sufficient operating stroke for the slider. can do. In addition, since the strength of the concave portion of the metal plate is higher than that of the portion that is not subjected to the drawing process, the mechanical strength of the bottom portion of the wafer is improved.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a switch device according to the present invention will be described below with reference to FIGS. Here, FIG. 1 is an exploded perspective view of this embodiment, FIG. 2 is a perspective view showing a shape of a metal plate constituting a wafer of the embodiment before molding, and FIG.
FIG. 4 is an explanatory view showing a manufacturing process of the clip-shaped fixed contact terminal in the embodiment, and FIG. 4 is an explanatory view showing an ascending and descending operation of the slider in the embodiment.

The switch device shown in these figures has a first fixed contact terminal 11 and a clip-shaped second fixed contact terminal 1 inside a casing 13 molded into a box with a bottom.
And a torsion coil spring 15 having a movable contact portion 15a which can be brought into contact with and separated from the second fixed contact terminal 12 and which is always in contact with the first fixed contact terminal 11.
And the drive unit 15b of the torsion coil spring 15
4, a columnar slider 16 that can be pressed toward the inner bottom surface,
A guide hole 17a through which the slider 16 is inserted is provided, and a case 17 that closes an upper opening of the wafer 14 is provided. The first and second wafers 14 are placed outside the casing 13 thereof. External connection terminals 18 and 19 respectively derived from the fixed contact terminals 11 and 12 are projected.

When manufacturing such a switch device, as shown in FIG. 2, by pressing a hoop material 20 made of a highly conductive metal plate, the first fixed contact terminal 11 and the external The protruding piece portion having the connection terminal 18 and the bridge portion having the external connection terminal 19 are formed by erecting the second fixed contact terminal 12, and then the hoop material 20 is sent to a mold (not shown) to be molded. By processing, a casing 13 having a predetermined shape supported and fixed to the hoop member 20 is formed, and the casing 13 and various terminals 11 and 1 are formed.
The wafer 14, which is an integrated product with the wafers 2, 18, and 19, is obtained. Here, the second fixed contact terminal 12 includes a pair of contact portions 12a extending from the front end side of a portion bent in a substantially U shape and elastically contacting each other, and a punch die 22 (see FIG.
Eccentric clip shape having a pair of upright portions 12c which stand on both sides of the bottom plate portion 12b and extend obliquely upward and different from the upright direction. And a pair of contact portions 1 as described later.
The movable contact portion 15a of the torsion coil spring 15 can be press-fitted between 2a.

Further, a metal plate integrated with the bottom of the wafer 14 and having the hoop material 20 as a base material is provided with a concave portion formed by drawing at a position facing the bottom surface of the slider 16 in a commercialized state. A recess 21 is provided, and the bottom surface of the recess 21 is exposed to the outside as is apparent in FIG. Further, a cylindrical guide wall 13 a for regulating the position of the outer peripheral surface of the slider 16 is projected from the housing 13 of the wafer 14 above the recess 20. The guide wall 13a has a torsion coil spring 15
A slit 13b for projecting the pressing portion 16a to the side is provided at a position corresponding to the pressing portion 16a for pressing and driving the driving portion 15b.

After the wafer 14 is formed, the torsion coil spring 15 is assembled at a predetermined position in the wafer 14 where the wafer 14 is always in contact with the first fixed contact terminal 11. The torsion coil spring 15 is, as shown in FIG.
A first winding portion 15c that generates a resilient force for urging the slider 16 in the ascending direction is provided at both ends of a substantially U-shaped connecting portion 15e having a driving portion 15a and a driving portion 15b. The first winding part 15c has an asymmetric shape in which a second winding part 15f, which has substantially the same diameter as that of the first winding part 15 and whose axial direction substantially matches, is protruded in the same direction. On the other end side of 15c, a fixed end portion 15d, which is fixed on the first fixed contact terminal 11 in a pressure contact state, protrudes. However, the number of turns of the second winding portion 15f of the torsion coil spring 15 is the first winding portion 1f.
The number of turns is set to be less than 5c.

Then, the torsion coil spring 15 is attached to the wafer 14
After being stored at a predetermined position in the inside, a case 17 mainly made of a metal plate is arranged on the wafer 14 with the slider 16 inserted through the guide hole 17a.
The case 17 is mounted on the wafer 14 from above by snapping the engaging projection 14a of the wafer 14 into the locking hole 17b of the above, and the assembly is completed.

In the switch device wafer 14 thus assembled, the first torsion coil spring 15
The winding portion 15c is pressed from above by the case 17, and the resilient force generated by the winding portion 15c
5b always urges the pressing portion 16a of the slider 16 upward.

Next, the operation of the above-described switch device will be briefly described. Now, assuming that no pushing operation force acts on the slider 16, the slider 16 is pushed up to the uppermost point (the position indicated by the solid line in FIG. 4) by receiving the elastic force of the torsion coil spring 15, so that the torsion coil spring The movable contact portion 15a of the fixed fixed contact terminal 1 has a clip shape.
2, the fixed contact terminal 12 and the first fixed contact terminal 11 are not electrically connected, and the circuit is kept off.

When the slider 16 is pushed downward by a predetermined amount, the driving portion 15b of the torsion coil spring 15 is pushed downward by the pressing portion 16a of the slider 16, so that the movable contact portion 15a is fixed in the form of a clip. Press-fitted between a pair of contact portions 12a of the contact terminal 12,
The first and second fixed contact terminals 11, 12 are conducted through the torsion coil spring 15, and the circuit is turned on. Thereafter, when the pushing operation force on the slider 16 is removed, the slider 16 is again pushed up to the uppermost point by the resilient force of the torsion coil spring 15, and the movable contact portion 15a is accordingly moved from the clip-like fixed contact terminal 12 to the movable contact portion 15a. Moving away, the circuit returns to the off state.

As described above, in this embodiment, the wafer 14
Of the metal plate integrated at the bottom of the slider 16
A recess 21 is provided at a location facing the bottom surface of the
Because the bottom surface of the metal plate is exposed to the outside, the location of the inner bottom surface is lower than that of the other portion, the thickness is as thin as the thickness of the metal plate, and the flow of the molten resin around the recess 21 is not hindered. The bottom plate portion is made of a synthetic resin and has a thickness that does not cause the problem. Therefore, in order to prevent a decrease in reliability due to a variation in a relative position with respect to a movable member (not shown) in a system serving as an actuator, the slider 1 is used.
If a desired long working stroke is secured in 6, the present embodiment has an advantage that the wafer 14 can be designed to be considerably thinner than the conventional product. The strength of the portion of the metal plate having the hoop material 20 as the base material where the recess 21 is formed is higher than that of the other portion not subjected to the drawing process. The mechanical strength at the bottom of 14 is also improved.

Further, the torsion coil spring 15 employed in the present embodiment is provided on the free end side of a connecting portion 15e extending in a substantially U-shape from the first winding portion 15c, with a fourth portion having substantially the same diameter as the winding portion 15c. 2
Is provided, there is no danger that the torsion coil springs 15 will be entangled even if a large number of them are mixed. Can be supplied automatically. And, this torsion coil spring 15
Since the second winding portion 15f substantially coincides with the first winding portion 15c in the axial direction, the connecting portion 15e is
During the operation of pushing the slider 16 or pushing up the slider 16, the second winding portion 15f hardly fluctuates, so that the deterioration of the ON position accuracy due to the wobbling of the movable contact portion 15a is avoided.

Further, in this embodiment, the slider 16
Since the cylindrical guide wall 13a that regulates the position of the outer peripheral surface of the slider 1 protrudes into the wafer 14, even if the slider 16 is set short to increase the operation stroke, the slider 1
There is no concern that the slider 6 will tilt or fall off during the lowering operation, and the relative positional accuracy between the slider 16 and the torsion coil spring 15 is also increased.

[0025]

As described above, the switch device according to the present invention is provided with a recess formed by drawing at a position facing the bottom surface of the slider in the metal plate integrated with the bottom of the wafer. Since the bottom surface of the recess is exposed to the outside, by moving the slider up and down above the recess, an excellent effect that a desired thickness can be achieved without sacrificing the operation stroke is achieved. Since the strength of the concave portion of the metal plate is higher than that of the portion that has not been subjected to the drawing process, an additional effect of improving the mechanical strength of the bottom portion of the wafer is obtained.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of the present embodiment.

FIG. 2 is a perspective view showing a shape of a metal plate constituting the wafer of the embodiment before molding.

FIG. 3 is an explanatory diagram showing a manufacturing process of the clip-shaped fixed contact terminal in the embodiment.

FIG. 4 is an explanatory diagram showing a lifting and lowering operation of the slider in the embodiment.

FIG. 5 is an exploded perspective view of a conventional example.

FIG. 6 is an explanatory diagram of an operation in an off state of the conventional example.

FIG. 7 is an explanatory diagram of an operation in an ON state of the conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 1st fixed contact terminal 12 2nd fixed contact terminal 12a Contact part 13 Housing part 13a Guide wall 14 Wafer 15 Torsion coil spring 15a Movable contact part 16 Slider 17 Case 18, 19 External connection terminal 20 Hoop material 21 Concave part

Claims (1)

(57) [Claims] 1. A wafer having a first fixed contact terminal and a clip-shaped second fixed contact terminal exposed inside, and a movable contact portion capable of coming into contact with and separating from the second fixed contact terminal. A torsion coil spring which is always in contact with the first fixed contact terminal; and a slider which is capable of pressing and driving a part of the torsion coil spring. A switch device for contacting / separating from a fixed contact terminal, wherein a concave portion formed by drawing is provided at a portion of a metal plate integrated with a bottom portion of the wafer facing a bottom surface of the slider. A switch device characterized in that a bottom surface of the place is exposed to the outside.