JPH0545038Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] This invention relates to a dip switch.

[Conventional technology and its issues]

Date switches are commonly used as switches for programming or selection in cordless telephones, multi-function telephones, computers, printers, copiers, fax machines, digital computers, vending machines, game machines, etc. It is mounted directly on the printed circuit board along with other components such as diodes.

However, in the past, this type of deep switch had a plurality of sets of lead terminals arranged on a molded insulating base, and a contact spring for the lead terminals was moved by a knob made of an insulating material. Therefore, the inside of the switch is easily charged, and when the operator operates the switch while his/her body is charged in dry conditions,
A large current momentarily flows through the printed circuit board circuit,
There was a problem in that it destroyed expensive circuit components such as ICs.

Conventionally, countermeasures against this problem include installing capacitors and resistors on printed circuit boards to prevent electrostatic damage.
Methods such as covering the entire printed circuit board with conductive foil were used.

However, this method cannot avoid a significant increase in cost due to the use of special electrical components and complicated processes, and also has problems such as a reduction in the mounting area of the printed circuit board due to the use of capacitors, etc. Ta.

Therefore, Japanese Utility Model Application No. 61-14437 proposes using a conductive cover with a bent ground terminal, but in this prior art, the conductive cover is a face plate that contacts the top surface of the casing; Since a long hole corresponding to the outline of the operating piece was formed, firstly, a large amount of material was used, and a complicated work was required to fix the face plate to the top surface of the casing by gluing or the like, and furthermore, the switch number etc. had to be printed. Because of this necessity, the cost is high, and secondly, there is a problem that the operation tends to shift due to misalignment between the operation piece and the elongated hole, making it difficult to use.

Note that Japanese Utility Model Application Publication No. 57-2303 proposes a means for preventing electrostatic damage in operation panels of microwave ovens, etc., but this prior art requires three members for grounding and does not fix the conductive cover. In order to do this, it is necessary to separately perform bonding, etc., which inevitably increases the cost.

The present invention was devised to solve the above problems, and its purpose is to provide a deep switch that can prevent electrostatic damage with a simple and inexpensive structure.

[Means for solving the problems]

In order to achieve the above object, the present invention includes a case made of synthetic resin in which multiple sets of lead terminals are arranged so as to extend outside, a plurality of contact springs that contact the lead terminals, and an opening of the case. It consists of a fitted lid made of a conductive material, a slidable knob made of an insulating material that is attached to the conductive lid and moves the contact spring, and an earth cover made of a conductive material, and the earth cover is made of a conductive material. , has a window that substantially matches the planar contour of the lid, and a frame with a conductive protrusion in contact with the surface of the lid on the inside of the window, and one set of outer edges of the frame has a frame that is attached to the side wall of the case. A side flange is formed that is bent at right angles, and the remaining outer edge part has a leg part with a ground terminal part extending therethrough, and the leg part has a latching part to the bottom surface of the case. It has a structure that has a claw piece for use.

〔Example〕

The present invention will be explained below by taking as an example a case where the present invention is applied to a sliding type deep switch.

Figures 1 to 3 show an embodiment of the deep switch of the present invention, in which 1 is a case (base) made of synthetic resin, and inside is a contact/separation space 11 formed by partition walls (not shown). A plurality of slits 12, 12' are formed at the bottom.

A horizontal stepped portion 2 for supporting the lid body is formed surrounding the upper opening portion, and a projecting edge portion that slopes in an inversely tapered shape from the horizontal stepped portion 2 is formed in the portion other than the four corners of the opening. 3 is formed.

Lead terminals 4 and 4' are inserted into each of the slits 12 and 12', the upper half of which is bent at right angles along the bottom side of the case and fixed at predetermined intervals. Reference numeral 5 denotes a contact spring that moves toward and away from the lead terminals 4, 4', and is comprised of two left and right tongue-shaped contact portions 50, 50 and a connecting portion 51 connecting the tops of the contact portions 50, 50.

Reference numeral 6 denotes a lid body, which is a plate made of a conductive material such as aluminum or aluminum alloy. This lid body 6 has elongated holes 7 for sliding knobs formed at positions corresponding to the lead terminals 4, 4, and are press-fitted so as to open the inversely tapered projecting edge 3 of the case 1. and is supported and fixed to the horizontal stepped portion 2 by the repulsive force of the projecting edge portion 3.

8 is a knob made of an insulating material, and the lid body 6
a sliding plate portion 81 in contact with the back surface of the slide plate portion 81; and an operating portion 82 projecting outward from the top surface of the sliding plate portion 81 through the elongated hole 7.
The lower surface of the sliding plate part 81 is provided with a recessed part 83 for enclosing the upper half of the contact spring 5.

Reference numeral 9 denotes a ground cover 9 assembled to the outside of the case 1.

The earth cover 9 is made of a conductive material such as phosphor bronze, copper alloy such as brass, or iron-based metal. This earth cover 9 has a structure as shown in FIG. That is, in this embodiment, the earth cover 9 consists of a frame body 90 equipped with a large window 91 that approximately matches the planar contour of the lid body 6.
As shown in FIG. 2a, a protrusion 92 for conduction to the surface 60 of the lid 6 is integrally formed inside the window 91. Although the number of the protrusions 92 shown in the drawing is one, there may be a plurality of protrusions 92.

In addition, a side flange 93 bent at right angles and in contact with the side wall of the case 1 is provided at the outer edge of the frame 90.
93 is formed, and legs 94, 94 are bent and formed on the remaining edge of the frame 90.
4 and 94 are extended with ground terminal portions 95 and 95 for connection to a printed circuit board. Claw pieces 96, 96 are bent and formed on the leg portions 94, 94,
By entering the claw pieces 96 into the lower surface of the case 1, the frame 90 is integrally assembled to the deep switch.

FIG. 4 shows an embodiment in which the surface of the front cover body 6 including the knob is sealed with a soft thin film 10.
The soft thin film 10 is made of a coating of a material that is soft, has good adhesion, good chemical resistance, and is self-hardening, such as a liquid silicone rubber compound. The adhesion method can be carried out, for example, by dropping the above-mentioned material onto a suitable location on the surface of the lid 6 and spreading it over the entire surface of the lid with air. The thickness of the membrane is usually approximately 0.1 mm or less in order to facilitate operation of the operating portion 82.

[Effect of the embodiment]

1 to 3, the legs 94, 94 of the earth cover 9 are in a horizontal state as shown by the imaginary lines in FIG. If the legs 94, 94 are bent in a state where the legs are positioned in the position shown in FIG. 96, 96 enter the bottom surface of the case 1 and come into contact with it, so that the ground cover 9 is fixed so that it does not move vertically or horizontally, and the protrusion 92 contacts the surface of the conductive lid 6, and is held firmly in this state. and can be held. Assembly is completed with a simple bending operation without using any adhesive.
Good efficiency.

This state is shown in FIGS. 2 and 2a, and since the frame structure is equipped with a window 91 that fully exposes the lid 6, the amount of material used can be reduced, and long holes corresponding to each knob can be used. Since there is no need to make a hole, processing is easy, and there is no hesitation in operating the switch due to misalignment between the knob and the slotted hole, making it possible to achieve smooth switch operation. Furthermore, the switch numbers and the like printed on the lid 6 can be used as they are, so the overall cost can be extremely low.

In use, it is sufficient to connect the ground terminals 95, 95 to the printed circuit board together with the lead terminals 4, 4', and the protrusion 92 of the frame 90 connects to the lid 6 made of conductive material.
case 1 because both are in a conductive state.
The static electricity charged inside flows from the lid 6 to the printed circuit board through the frame 90, legs 94, 94, and ground terminals 95, 95, and is grounded by a circuit section provided therein in advance.

Further, even when an operator who is in a charged state touches the knob 8 with his or her finger, the lid body 6 and the frame body 90 are efficiently grounded through the route, so that electrostatic damage is completely prevented.

Note that when the soft thin film 10 is applied to the surface of the lid 6, the minute gap at the press-fit interface between the lid 6 and the case 1 and the minute gap between the elongated hole 7 and the knob top surface 81 are sealed. , it is possible to completely prevent the infiltration of cleaning agents and dust during washing after soldering. Therefore, high precision can be achieved. In addition, since it is a soft thin film 10, the operation of the knob 8 is not hindered in any way, and the seal at that portion is released by sliding the knob. Therefore, a preferable virgin seal function can also be exhibited.

[Effect of idea]

According to the present invention described above, there is provided a case 1 made of synthetic resin in which a plurality of sets of lead terminals 4, 4' are arranged so as to extend outside, and a plurality of contact springs that contact the lead terminals 4, 4'. 5, a lid body 6 made of a conductive material fitted into the opening of the case 1, a slidable knob 8 made of an insulating material attached to the lid body 6 made of conductive material and moving the contact spring 5, and a conductive The earth cover 9 includes a window 91 that substantially matches the planar contour of the lid 6, and a conductive protrusion 9 inside the window that contacts the surface of the lid 6.
2, one set of outer edges of the frame 90 are formed with side flanges 93, 93 bent at right angles that contact the side walls of the case 1, and the remaining one set of edges The leg portions 94, 94 are integrally provided with a ground terminal portion 95 extending therefrom, and the leg portions 94, 94 have claw pieces 96, 96 for locking onto the lower surface of the case 1.
Because of this, the amount of material used for the earth cover 9 is small, and there is no need to print switch numbers, etc. As a result, the earth cover 9 can be immovably integrated with the case 1 by a simple operation without using adhesive, and a stable conductive circuit can be formed with the lid body 6 and the conductive protrusion 92. Therefore, an excellent effect can be obtained in that a deep switch with good electrostatic damage prevention performance can be obtained at a very low cost.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing an embodiment of the deep switch according to the present invention, Fig. 2 is a sectional view taken along the line shown in Fig. 1, Fig. 2a is a partially enlarged view thereof, and Fig. 3 is an exploded perspective view of the present invention. FIG. 4 is a sectional view showing another embodiment of the present invention, and FIG. 4a is a partially enlarged view thereof. 1...Case, 4, 4'...Lead terminal, 5...
...Contact spring, 6...Lid, 8...Knob, 9...
Earth cover, 90... Frame, 91... Window, 92
... Protrusion, 93, 93 ... Side flange, 94,
94... Leg, 95, 95... Earth terminal, 9
6,96...Claw piece.

Claims (1)

[Scope of utility model registration request] a case 1 made of synthetic resin in which a plurality of sets of lead terminals 4, 4' are arranged so as to extend to the outside; a plurality of contact springs 5 in contact with the lead terminals 4, 4';
A lid body 6 made of a conductive material fitted into the opening of the case 1
and a slidable knob 8 made of an insulating material that is attached to the conductive lid 6 and moves the contact spring 5.
The window 9 is made of a ground cover 9 made of a conductive material, and the ground cover 9 substantially matches the planar contour of the lid 6.
1 and a frame 90 equipped with a conductive protrusion 92 in contact with the surface of the lid 6 on the inside of the window.
Side flanges 93, 93 bent at right angles that contact the side wall of the case 1 are formed on the outer edges of the pairs, and leg portions 94, 94 with ground terminal portions 95 extending are formed on the edges of the remaining pair. are integrated, and the legs 94, 9
4 is a claw piece 9 for locking the bottom surface of the case 1.
6.96.