JP2000113764A - Switch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a switch excellent in waterproofing, capable of securing a sufficient height corresponding to the thickness of a potting layer, excellent in assembling, and manufacturable at a relatively low cost. SOLUTION: This switch comprises a base 1a, housing a switching mechanism 8 as well as a plunger 9 for operating this in its recessed part and having lead terminals (3), 4 projectingly provided on its outer surface, and a cover case 1b connected to an opening end part of the base 1a and equipped with a push button 2 acting on the plunger 9. An elastically deformable sheet-like seal body 21 is sandwiched between a seal surface (19) formed on the opening end part of the base 1a and a seal surface (20) formed on an end part of the cover case 1b, and the whole of the opening end part of the base 1a is closed by the seal body while the displacement of the push button 2 is transmitted to the plunger 9 via the seal body 21.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a small-sized switch mounted on a board of an electric appliance, such as a washing machine or a dishwasher, which is often splashed with water.

[0002]

2. Description of the Related Art A board mounted on such an electric device is potted with a moisture-proof material for waterproofing, and a switch used for such a board is connected to a base and the base. A switching mechanism and operation members such as push buttons for operating the switching mechanism are incorporated inside the main body case consisting of the cover case, and a seal ring and a bellows for sealing are provided at the projecting part of the cover case to make it waterproof. Was used.

[0003]

However, in the conventional switch, since the height of the entire body case is set corresponding to a potting layer having a certain thickness, the substrate on which the potting layer is formed to be thick is required. In order to cope with potting layers having different thicknesses, it was necessary to prepare many types of switches having different specifications, which resulted in a problem that the cost was increased.

Further, in order to increase the waterproofness at the projecting portion of the operating member, it is desirable to set the contact pressure of the seal ring to be high. However, the higher the contact pressure of the seal ring, the more the operating member is operated. However, the operation resistance of the above-mentioned device tends to increase, and a large difference tends to occur in the operation resistance due to a manufacturing error, which makes it difficult to stabilize the quality. The use of the bellows for sealing does not cause the above-mentioned problems relating to the operation resistance, but on the other hand, it increases the cost of the sealing member itself and requires a lot of trouble in assembling to lower the productivity. Was.

The present invention has been made in view of such a situation, and is excellent in waterproofness, and can sufficiently secure a height corresponding to the thickness of the potting layer. An object of the present invention is to provide a switch which is excellent in workability and can be manufactured at relatively low cost.

[0006]

In order to achieve the above object, the present invention has the following configuration.

That is, the switch according to the first aspect of the present invention accommodates a switching mechanism and a plunger for operating the switching mechanism in a recess, and has a base having lead terminals protruding from an outer surface thereof, and is connected to an opening end of the base. Along with
A cover case provided with an operating member acting on the plunger, wherein an elastically deformable seal body is sandwiched between a seal surface formed at an open end of the base and a seal surface formed at an end of the cover case. Then, the entire opening end of the base is closed by the seal body, and the displacement of the operation member is transmitted to the plunger via the seal body.

According to a second aspect of the present invention, in the switch according to the first aspect, the seal body includes a resin film adhered to the seal surface of the base and a rubber sheet polymerized thereon. .

According to a third aspect of the present invention, in the switch according to the second aspect, an annular projection is formed on the sealing surface of the cover case so as to bite into the rubber sheet of the seal body. The film is bonded to the sealing surface of the base with an adhesive.

A switch according to a fourth aspect of the present invention is the switch according to the second or third aspect, wherein the resin film and the rubber sheet are integrated by laminating and bonding.

The invention according to claim 5 is the invention according to claims 1 to 4
The switch according to any one of the above, wherein the switches are arranged in parallel at a constant pitch along the longitudinal direction of the long transport tape, and the lead terminals projecting from the transport tape and a pressing tape adhered thereto are provided. Held in between.

According to the structure of the first aspect of the present invention, the cover having an arbitrary height is connected to the base in which the switching mechanism is installed, so that the entire height of the switch is arbitrarily set. Can be obtained. here,
Since the inside of the base is completely insulated from the outside by the seal body, even if water or the like enters the cover case, it does not reach the switching mechanism and exhibits extremely high waterproof performance. It is not necessary to equip the projecting portion with a sealing material such as a seal ring or a seal bellows. Nevertheless, the displacement of the operating member is reliably transmitted to the plunger inside the base by the deformation of the seal,
Contact switching of the switching mechanism can be performed.

According to the construction of the second aspect of the invention, since the sealing body is composed of the resin film and the rubber sheet superposed on the resin film, the resin film is formed on the sealing surface of the base over the entire circumference by the elastic force of the rubber sheet. It is possible to perform pressure bonding uniformly and stably. Here, a resin material such as polyimide is used for the resin film, and NBR is used for the rubber sheet.
When the seal body is made to have high chemical resistance by using, the durability of the substrate on which the switch is mounted to the ambient atmosphere becomes high.

According to the third aspect of the present invention, the annular projection formed on the end surface of the cover case bites into the rubber sheet, and the sealing surface of the cover case and the rubber sheet are pressed in an annular shape, and are formed all around the sealing surface. High sealing performance is exhibited throughout. In addition, since the resin film is bonded with the adhesive, the resin film can be more securely and firmly adhered to the entire sealing surface of the base.

According to the structure of the invention, when the cover case is connected to the base, a single sealing body is formed by laminating and bonding a resin film and a rubber sheet between the sealing surfaces of the two cases. Should be assembled.

According to the configuration of the fifth aspect of the invention, it is possible to supply in a taping package and perform automatic mounting.

[0017]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a side view of a switch according to the present invention in a longitudinal section, FIG. 2 is an external perspective view thereof, and FIG. 3 is an exploded perspective view thereof. The switch A has a front and rear and left and right width dimension of about 8 mm and a height of about 9 mm. A pair of lead terminals 3 and 4 are provided on the bottom surface of the main body.

The case 1 comprises a resin base 1a having lead terminals 3 and 4, and a resin cover case 1b connected to the upper end of the base 1a. The base 1a and the cover case 1b are integrated by inserting the pins 5 into the connection holes 6 formed at the four lower corners of the cover case 1b and thermally caulking them.

A circular recess 7 opened upward is formed in the base 1a, and houses a switching mechanism 8 and a plunger 9 for operating the switching mechanism. As shown in FIG. 4, the switching mechanism 8 includes the recess 7.
A circular contact 10 located at the center of the bottom surface of the pair, a pair of rectangular contacts 11 located on both left and right sides thereof, and a disk-shaped movable contact plate 12 disposed on these, One lead terminal 3 extends from the center contact 10, and the other lead terminal 4 extends from a pair of contacts 11.

The movable contact plate 12 is curved so as to protrude slightly upward. In a normal state, as shown in FIG. And the central contact 10
, And a switch-off state in which the conduction between the two lead terminals 3 and 4 is cut off is brought about. When the central portion of the movable contact plate 12 is pressed downward, the central portion of the movable contact plate 12 is reversely deformed and brought into contact and conduction with the central contact, so that a switch-on state in which both lead terminals are conducted is provided, and the switch is pressed down. Is released, the movable contact plate 12 is restored to its original shape and returned to the switch-off state.

The lead terminals 3 and 4 and the contact 1
Numerals 0 and 11 are inserted into the base 1a, and as shown in FIG. 6, a pair of lead frames 1 formed by punching a long hoop material 13 at regular intervals.
Contact points 10 and 11 are respectively connected to 4, 15 and 15,
The bases 1a are formed by subjecting the lead frames 14 and 15 to injection molding, and then cut along cut lines C1 and C2 so that the lead terminals 3 and 3 extend laterally from the base 1a.
A primary product from which 4 has been extended is manufactured. Thereafter, by bending the lead terminals 3 and 4 extending laterally, the base 1a having the lead terminals 3 and 4 protruding from the bottom surface is formed.

The plunger 9 is inserted into the recess so as to be able to move up and down along a pair of guide grooves 16 formed on the inner wall surface of the recess 7. The movable contact plate 12 comes into contact with the upper surface of the center.

The connecting pin 5 of the base 1a is
a The projections are provided from the connection seats 17 formed at the four corners at the upper end, and the four corners of the cover case 1b are cut out for inserting a caulking tool, thereby forming a thin connection portion 18 having the connection hole 6. Then, the connecting portion 18 is directly placed on the connecting seat 17 of the base 1a, and the cover case 1b is caulked to the base 1a.

Except for the connection seats 17 at the four corners, a seal surface 19 which is annularly continuous is formed at the upper end opening of the base 1a.
Is formed one step lower, and a sealing surface 20 that fits between the connection seats 17 and faces the sealing surface 19 is also formed on the lower end surface of the cover case 1b. Here, the raised height of the sealing surface 20 on the cover case side is set smaller than the depth of depression of the sealing surface 19 on the base side, and the cover case 1b is mounted and connected to the base 1a via the connecting seat 17 and the connecting portion 18. In this state, a gap having a predetermined size is formed between the two sealing surfaces 19 and 20.

In the gap formed between the two sealing surfaces 19 and 20, a sheet-like sealing member 21 for entirely closing the upper end opening of the base 1a is interposed.

The seal body 21 is formed of a resin film 22 made of polyimide and a rubber sheet 23 made of NBR which is polymerized on the resin film 22 so that it can be positioned and mounted on the recessed sealing surface 19 of the base 1a. , And their respective external shapes are set.

As shown in FIG. 5, an annular projection 24 is formed on the seal surface 20 of the cover case 1b, and the seal body 21 is sandwiched between the upper and lower seal surfaces 19, 20. The annular projection 24 cuts into the upper surface of the rubber sheet 23, and the upper surface of the seal body 21 and the cover case 1
The sealing surface 20b is in close contact with the entire circumference.

The push button 2 is inserted from the downward opening of the cover case 1b and protrudes from the hole 26 on the upper surface of the case so as not to come out. A pin-shaped operation portion 2a is provided so as to protrude so as to act on the operation portion.

The switch A according to the present invention is configured as described above. When assembling, first, the movable contact plate 12 and the plunger 9 are inserted sequentially into the concave portion of the base 1a, and then the upper end is opened. Resin film 2 on the sealing surface 19
2 is bonded via an adhesive applied to the entire lower surface thereof,
The rubber sheet 23 is positioned and mounted thereon. afterwards,
Cover case 1b with push button 2 attached to base 1a
The cover case 1b is connected to the base 1a by heat caulking the connecting pin 5 inserted into the connecting portion 18 and the sealing body 2 is provided between the sealing surfaces 19 and 20.
1 is sandwiched to seal between the two cases.

The switches A manufactured as described above are arranged in parallel at a constant pitch on the transport tape 26 as shown in FIG. And the holding tape 27 adhered thereon. As described above, the switches A are transported and stored in a predetermined number unit (for example, in units of 1000) while being held at a constant attitude and a constant pitch on the transport tape 26, and can be supplied to an automatic mounting machine when used. Thus, the total cost for the user can be reduced.

The present invention can be embodied in the following modes.

To form the seal body 21, the material of the rubber sheet 23 is previously bonded to the material of the resin film 22 by using an adhesive and laminated integrally, and then punched into a predetermined shape. Laminated seal body 21 formed in
May be loaded on the sealing surface 19 of the base 1a and attached. Further, a resin film 22 may be stuck on the upper and lower sides of the rubber sheet 23 to form the seal body 21 having a three-layer structure.

In the above embodiment, a part of the seal body 21 is exposed on the outer surface of the case. However, the connection seat 17 provided with the connection pin 5 is continuously formed in an annular shape, and a seal face is provided inside the connection seat 17. By forming the lower part 19 into a recess and fitting the raised seal surface 20 of the cover case 1b inside the connection seat 17, a structure in which the seal body 21 is not exposed to the outer surface of the case can be obtained.

As a structure for connecting the base 1a and the cover case 1b, a well-known connecting means such as a screw connection or a screw connection may be appropriately selected according to the size of the switch A, in addition to using a heat caulking means. I just need.

[0036]

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

According to the first aspect of the present invention, the cover case is connected to the base which is completely hermetically sealed by the seal body, so that the specifications of the cover case can be set arbitrarily and a desired waterproof property can be obtained while enhancing the waterproofness. Height switches can now be easily configured.

Since the cover case connected to the completely waterproof base does not need to be provided with a particularly waterproof function, a seal ring or a group which provides a large operation resistance is provided at the projecting portion of the cover case. There is no need to equip with sealing materials such as bellows that require time to attach,
A switch with excellent waterproofness and stable quality can be provided at low cost.

Further, since the open end of the base is waterproofed only by sandwiching the sheet-shaped seal body between the seal surface of the base and the seal surface of the cover case, it is possible to fit the seal member into a mounting groove or the like. It is easy to assemble because it does not require time and effort, and it is possible to obtain high waterproof performance even if the processing accuracy of the seal body and the sealing surface is not particularly high. Becomes

According to the second aspect of the present invention, since the seal member repeatedly deformed by the operating member has a laminated structure in which a resin film having excellent toughness and a rubber sheet having excellent elasticity are polymerized, durability is improved. High waterproofness can be exhibited while enhancing the performance.

According to the third aspect of the present invention, the adhesion between the sealing surface of the cover case and the rubber sheet is improved, which is effective in enhancing the waterproofness. Further, since the resin film of the sealing body is brought into close contact with the sealing surface of the base with an adhesive, the waterproofness can be further enhanced, and the above effect of the invention of claim 2 is promoted.

According to the fourth aspect of the present invention, the seal body in which the resin film and the rubber sheet are laminated and bonded in advance is not as flexible as the resin film alone, so that it is easy to handle. The assembling workability is improved as compared with the case of separately assembling.

According to the fifth aspect of the present invention, the completed switch group can be easily transported and managed in units of transport tapes, and can be effectively used for automatic supply of switches when performing automatic assembly. it can.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional front view of a switch according to the present invention.

FIG. 2 is a perspective view of the entire appearance.

FIG. 3 is an exploded perspective view.

FIG. 4 is a plan view of a base.

FIG. 5 is a perspective view of the cover case viewed from the lower surface side.

FIG. 6 is a perspective view showing a material of a lead terminal and a contact inserted into a base.

FIG. 7 is a perspective view showing an example of a transport storage mode of the completed switch.

[Explanation of symbols]

 1a Base 1b Cover Case 2 Operation Member (Push Button) 3 Lead Terminal 4 Lead Terminal 7 Recess 8 Switching Mechanism 9 Plunger 19 Seal Surface of Base 20 Seal Surface of Cover Case 21 Seal Body 22 Resin Film 23 Rubber Sheet 24 Annular Protrusion 26 Transport Tape 27 Holding tape

Claims (5)

[Claims] 1. A switching mechanism and a base having a plunger for operating the switching mechanism housed in a recess and having a lead terminal protruding from an outer surface, and an operating member connected to an open end of the base and acting on the plunger. An elastically deformable seal body is interposed between a seal surface formed at an open end of the base and a seal surface formed at an end of the cover case, and an open end of the base is provided. A switch, wherein the whole part is closed by the seal body, and the displacement of the operation member is transmitted to the plunger via the seal body. 2. The switch according to claim 1, wherein said seal body is composed of a resin film adhered to said seal surface of said base and a rubber sheet polymerized thereon. 3. The sealing surface of the cover case,
3. The switch according to claim 2, wherein an annular protrusion that cuts into the rubber sheet of the seal body is formed, and the resin film is adhered to the seal surface of the base with an adhesive. 4. The switch according to claim 2, wherein the resin film and the rubber sheet are laminated and bonded to be integrated. 5. The switch according to claim 1, wherein the switches are arranged in parallel at a constant pitch along a longitudinal direction of a long transport tape and transport the projecting lead terminals. A switch held between the tape and the holding tape adhered to it.