JPH0117053Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a grounding structure for an ultra-small switch that can remove charges that accumulate on the surface of the switch.

FIG. 1 shows the grounding structure of a conventional ultra-compact switch. A plurality of terminals 12 are provided on mutually parallel side surfaces of the switch case 11 and connected to a fixed contact piece and a common contact piece (not shown) disposed inside the switch case 11. In this switch, a movable contact piece (not shown) is driven in response to the operation of the push button 13, and the movable contact piece brings the fixed contact piece and the common contact piece into contact and separation, thereby changing the switch state. . Further, the switch case 11 is provided with a metal cover 14, and the cover 14 has a ground terminal 14 ₁ corresponding to a side surface perpendicular to the side surface of the switch case 11 on which the terminal 12 is disposed. It is provided. Therefore, the charge that is naturally charged on the push button 13, etc.
Charges transferred by the operator when the push button 13 is operated can be grounded via the ground terminal ₁₄₁ .

By the way, this type of ultra-compact switch is often mounted on a printed wiring board. Therefore, it is desirable that the terminal arrangement be of the dual in-line package type, similar to the integrated circuit elements to be mounted together. However, as mentioned above, cover 14
Therefore, the method of forming the ground terminal ₁₄₁ makes it difficult to form a dual in-line package type.

This invention was made based on the above circumstances, and its purpose is to provide a grounding structure for an ultra-compact switch that allows for a dual in-line package type terminal arrangement.

An embodiment of this invention will be described below with reference to the drawings.

In FIGS. 2 to 6, the case 31 is provided with a recess 31 ₁ . Terminals 32, 33, 34, 35 are provided on both parallel sides of this case 31.
And ground terminals 36 and 37 are formed as inserts with a predetermined spacing between them. The terminals 33, 35 are integrally formed as shown in FIG. 6, and the conductors constituting these terminals 33, 35 are exposed inside the recess ₃₁₁ at a predetermined distance, and the fixed contact pieces 38,
89 is formed. Further, the terminals 32, 34
The conductors constituting these terminals 32 and 34 are exposed inside the recess 31 ₁ and between the fixed contact pieces 38 and 39, forming a common contact piece 40. Further, the ground terminals 3 each have a base end buried in the side surface of the case 31.
6 and 37 are exposed in recesses 31 ₂ and 31 ₃ provided on the side surfaces perpendicular to this side surface, and
Mounting holes 31 ₄ provided on the surface of the case 31,
31 ₅ exposed.

On the other hand, both ends of a dome-shaped movable contact piece 41 are placed on the fixed contact pieces 38 and 39, and this movable contact piece 4
1 includes a projection 42 ₁ provided on the back side of the push button 42
is in contact. The push button 42 is made of an elastic member such as nitrile rubber, and the flange 42 ₂ of the push button 42 is pressed and held by the case 31 and the cover 43. As shown in FIG. 5, a through hole 43 ₁ is provided in the center of the cover 43, through which the operating portion 42 ₃ of the push button 42 is inserted. A recess 43 ₂ is provided around the through hole 43 1 and on the back surface of the cover 43 in which a protrusion 42 ₄ provided at the peripheral edge of the flange 42 ₂ of the push button ₄₂ is accommodated. The depth of this recess 43 ₂ is the protrusion 42 ₄
It is shallower than the thickness of. Moreover, the recess 43
₂ , there is a protrusion 43 called an energy director that fits into a groove 31 ₆ (shown in FIG. 4) provided around the recess 31 ₁ in the case 31.
₃ and the mounting holes 31 ₄ , 3 in the case 31
1 ₅ are provided with protrusions 43 ₄ , 43 ₅ that can be fitted into each other. Further, the side surface of the cover 43 is provided with recesses 43 ₆ and 43 ₇ that can communicate with the recesses 31 ₂ and 31 ₃ provided on the side surface of the case 31. Thus, with the protrusion 42 ₂ of the push button 42 accommodated in the recess 43 ₂ of the cover 43, the protrusion 4 of the cover 43
3 ₄ , 43 ₅ and the mounting holes 31 ₄ , 31 ₅ of the case 31 are fitted, and the protrusion 43 ₃ of the cover 43 and the groove 31 ₆ of the case 31 are fitted, and then ultrasonic welding is performed. When this is done, the vicinity of the protrusion 43 ₃ is melted, and the case 31 and cover 43 are fixed together.

Furthermore, in the above state, a grounding member 44 is detachably provided on the cover 43 as shown in FIGS. 2 and 3. This grounding member 44 is made of a metal plate, for example, and has an operating section 42 of the push button 42 in its center.
A through hole 44 ₁ into which ₃ is inserted is provided. Furthermore, engaging portions 44 2 and 44 3 are bent and formed at portions corresponding to the recesses 31 ₂ , 31 ₃ , 43 ₆ , and 43 ₇ that are provided on the side surfaces of the case ₃₁ and the cover _{43 and} communicate with each other. There is. Therefore, the grounding member 44 is connected to the cover 4.
3, the engaging portions 44 ₂ , 4
4 ₃ are respectively engaged with the lower surface of the case 31 through the recesses 31 ₂ , 31 ₃ , 43 ₆ , 43 ₇ , and in this state are electrically and mechanically connected to the ground terminals 36 and 37, respectively. .

According to the above configuration, the ground terminals 36 and 37 are arranged on both sides of the case 31 where the terminals 32 to 35 are arranged, and the ground terminals 36 and 37
are exposed from the recesses 31 ₂ and 31 ₃ provided on the side surface of the case 31, and the exposed ground terminals 36 and 37
The engaging portions 44 ₂ and 44 ₃ of the grounding member 44 attached to the cover 43 are electrically and mechanically connected.
Therefore, the terminal arrangement should be dual, inline,
In addition, even in the case of a dual in-line package type, the engaging portions 44 ₂ , 44 ₃ of the grounding member 44 are provided in the recesses 31 2 , 3 on the side surfaces of the case ₃₁ and the cover 43.
1 ₃ , 43 ₆ , 43 ₇ through the ground terminals 36 and 3
7, the case 31 and cover 43
The shape of the case 31 and the cover 43 can be made to closely resemble an integrated circuit package, with almost no effect on the shape of the case 31 and the cover 43.

In addition, since the grounding member 44 is detachable, 1
One switch can be used as two types of switches. Moreover, the grounding member 44 can be attached and detached even when the switch is mounted on a printed wiring board, so it has high utility value.

Furthermore, since the ground terminals 36 and 37 are arranged at positions that are point symmetrical with respect to the center of the case 31, the positions of the ground terminals 36 and 37 do not change even when the case 31 is rotated by 180 degrees.
This has the advantage of not imposing any restrictions on circuit pattern design.

As described in detail above, according to this invention, it is possible to provide a grounding structure for an ultra-compact switch in which the terminal arrangement can be made into a dual in-line package type.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing an example of the grounding structure of a conventional ultra-small switch, and Figs. 2 to 6 show an example of the earthing structure of the ultra-small switch according to this invention. 3 is a top view, FIG. 3 is a side sectional view, FIGS. 4 to 6 show the main parts of FIGS. The figure is a bottom view of the cover, No. 6
The figure is a top view of the case showing the terminal configuration. 31...Case, 31 ₁ ...Recess, 32-35
...Terminal, 36,37...Earth terminal, 38,3
9...Fixed contact piece, 40...Common terminal, 41...
Movable contact piece, 42...Push button, 42 ₃ ...Operation unit, 4
3... Cover, 43 ₆ , 43 ₇ ... Recess, 44...
Grounding member, 44 ₂ , 44 ₃ ... engaging portion.

Claims (1)

[Scope of utility model registration request] A switch mechanism consisting of a case having a recess, a fixed contact piece, a common contact piece, a movable contact piece that can connect these pieces arranged at the inner bottom of the recess part, and an operation part that drives the movable contact piece, and a switch mechanism of the case. the fixed contact pieces provided on both side surfaces parallel to each other;
a terminal connected to a common contact piece; and a ground terminal having a base end buried in at least one of the both sides of the case, and a part of the base end being exposed on a side surface perpendicular to the side surface. a cover that is attached to cover the recessed portion of the case through which the operating portion is inserted; and an engaging portion that is connected to the exposed base end of the ground terminal; A grounding structure for an ultra-compact switch characterized by being equipped with a grounding member that can be freely attached.