JPH0338744Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a push-on switch that can maintain good conductivity even when dirt, dust, etc. enter or are generated.

[Prior Art] Conventionally, a push-on switch having a configuration as schematically shown in FIG. 5 has been proposed. In the figure, reference numeral 1 denotes an insulating case body made of an insulating material;
has a cylindrical recess 1a, and a center contact 2a and an end contact 2b are provided at the center and end portions of the bottom surface of the recess 1a, respectively, with their contact end surfaces exposed. . In the recess 1a of the case body 1, a dish-shaped movable contact 3 made of a conductive metal plate and capable of reversible operation with an upwardly protruding central portion is housed.The movable contact 3
The edge of is in constant contact with the end contact 2b.

Further, as shown in FIG. 6, a hole 4 having at least one protrusion 4a is formed in the center of the movable contact 3. An operating member 5 is provided above the movable contact 3. When the movable contact 3 is operated and pushed down, the operating member 5 deforms the movable contact 3 and moves so that the center portion of the movable contact contacts the center contact 2a. 6 is provided with a through hole 6a in the center into which the operating portion 5a of the operating member 5 is loosely fitted, and is fixed to the opening end surface of the case body 1 by an appropriate method so as to confine the operating member 5 within the case body 1. This is a fixing plate. In this push-on switch,
A protrusion 4 is inserted into the hole 4 provided in the center of the movable contact 3.
a is provided, it is possible to increase the contact pressure when the operating member 5 is moved downward to bring the peripheral edge of the hole 4 of the movable contact 3 into contact with the center contact 2a.

[Problems to be solved by the invention] However, in the conventional push-on type switch, not only does the processing step for forming the deformed hole 4 increase, but also a special mold is required, and it takes a long time to form the deformed hole 4. There is a problem in that when the protrusion 4a is used in a stretched state, the protrusion 4a deforms and good contact cannot be obtained. In addition, in the conventional switch, the center contact 2a
Since the exposed end face is formed into a shape that is either a flat surface as shown in the figure or a simple curved surface such as a hemispherical surface, dirt, dust 7, etc. that entered through the through hole 6a of the fixing plate 6 will be trapped in the central part. If it gets between the contact 2a and the movable contact 3, there is a problem that poor contact will occur.

The object of the present invention is to provide a push-on switch that solves the above problems.

[Means for Solving the Problems] In order to solve the above-mentioned problems, the push-on type switch of the present invention is shown in FIGS. 1 to 4 showing embodiments.
As seen in the figure, an insulating case body 10 having a recess 10a, and a recess 10 of the case body 10.
Central contact 12a and end contact 1 fixed to a
2b ₁ , 12b ₂ and a hole 14 in the central portion thereof, and are accommodated in the recess 10a such that the end edges are in contact with the end contacts 12b ₁ , 12b ₂ , and the central portion faces toward the opening side of the recess 10a. A dish-shaped movable contact 13 that is curved so as to protrude and can be reversed, and when operated, moves within the recess 10a so that the peripheral edge of the hole 14 of the movable contact 13 contacts the central contact 12a. The operating member 15 is provided with an operating member 15.

The shape of the peripheral edge of the hole 14 of the movable contact 13 is approximately circular, and the central contact 12a protrudes toward the hole 14 of the movable contact 13, and its outer surface converges toward the tip. It has a polyhedral shape with at least two ridge lines 12a ₂₂ .

In this specification, the term "edge line" refers to a continuous line formed by the intersection of one surface and another surface.

[Operation of the invention] In the invention, the shape of the peripheral edge of the hole of the movable contact is formed into a substantially circular shape, the central contact is made to protrude toward the hole of the movable contact, and the outer surface thereof is made to face toward the tip. Since it is formed into a multifaceted shape having at least two converging ridge lines, contact failure due to local deformation of the hole of the movable contact can be prevented, and at least the ridge lines formed on the outer surface of the center contact and the hole of the movable contact can be prevented. Two or more contact parts can be formed between the peripheral edge of the part and the peripheral part of the part. Therefore, even if dust is present in one contact part, electrical contact can be maintained by the other contact parts, so that poor contact due to the intrusion of dust and dirt can be prevented. In addition, since the contact part is formed on the ridgeline of the center contact, even if dirt or dust gets on the ridgeline,
This has the advantage that dirt and dust fall off naturally.

[Examples] Examples of the present invention will be described in detail below with reference to the drawings.

FIG. 1 shows a schematic cross-sectional view of one embodiment of the present invention, and FIG. 2 is the same version of FIG. Figure 3 shows a plan view of the embodiment.
In these figures, reference numeral 10 denotes an insulating case body made of an insulating material and having a rectangular prism shape, and the case body 10 has a recess 1 that opens upward.
0a is formed. The inner surface of the recess 10a includes flat surface portions 10b ₁ to 10b ₄ having flat surfaces protruding in all directions at intervals of 90 degrees, and a curved surface portion 10 connecting these flat surface portions 10b ₁ to 10b ₄ .
c ₁ to 10c ₄ . Furthermore, these curved surface parts 1
0c ₁ to 10c ₄ each form a part of a cylindrical curved surface having the same radius.

At the bottom of the recess 10a of the case body 10, there is a center contact 12a and a pair of end contacts 12b ₁ and 12b _2.
are embedded and fixed in such a way that their contact end surfaces are exposed on the bottom surface of the recess 10a. These contacts are connected to output terminals 17a to 17d of the switch. In FIG. 2, the end contacts 12b ₁ and 12b ₂ are shown by dotted lines that are embedded in the case body 10.
and output terminals 17a, 17b and center contact 12a
The output terminals 17c and 17d are integrally formed from conductive metal plates 17A and 17B, respectively.

The portions of the end contacts 12b ₁ and 12b ₂ that protrude toward the bottom side of the recess 10a are the base portions 12b ₁₁ and 12b ₂₁ having a rectangular outer shape, and the semicylindrical contact portions 12b _{12 and 12b} protruding from the center of the base portions. 12b ₂₂
It is composed of. Base part 12b ₁₁ and 1
As shown in FIG. 2, 2b ₂₁ has a length approximately equal to the length of flat surface portions 10b _{2 and 10b 4 formed on the inner circumferential surface of the case 10, and has a length dimension approximately equal to that of flat surface portions 10b 2} and 10b ₄ formed on the inner circumferential surface of the case 10. The width dimension is such that the end portion is embedded in the case body 10. By embedding a portion of the flat surface portion in the case body 10 in this manner, the base portions 12b ₁₁ and 12b ₂₁ can be reliably fixed at predetermined positions. The shape of the center contact 12a will be described later.

13 is a movable contact formed of an elastic conductive metal plate and capable of reversing operation;
has a disk shape with a central portion protruding toward the opening of the recess 10a. The circular edge of the movable contact contacts the four curved surfaces 10c1 to 10c4 that constitute the inner circumferential surface of the recess 10a, and constantly contacts the contact portions 12b _{12 and} 12b ₂₂ of the end contacts 12b ₁ and 12b 2. It is housed in the recess 10a so as to. At the center of the movable contact 13 is a hole 14 whose peripheral edge is approximately circular.
is formed. In this embodiment, the recess 10a
A flat surface portion 1 that does not come into contact with the movable contact 13 on the inner peripheral surface of the
0b ₁ to 10b ₄ are provided and the end contact 1
Since the step is provided between the contact portions 12b ₁₂ and 12b ₂₂ of 2b ₁ and 12b ₂ and the base portions 12b ₁₁ and 12b ₁₂ , even if the movable contact 13 is deformed, the movable contact 13 and the recess 10a can be easily This allows the air between the base and the bottom to be removed, resulting in smooth operation.

The center contact 12a, which is disposed approximately in the center of the recess 10a of the case body 10, is formed by stamping as shown in FIG.
The first part 12a ₁ buried in the bottom of a and the recess 1
A second portion 12a ₂ exposed from the bottom surface of 0a. The first portion 12a ₁ has an approximately bead-shaped outer shape, and is bent through a neck portion 17B ₁ that is appropriately bent to ensure that the second portion 12a ₂ is exposed from the bottom surface of the recess 10a. Output terminal 1
It is connected to the connection portions 7c and 17d.

The second portion 12a ₂ of the central contact 12a has a circular bottom surface, and a central portion protrudes toward the hole 14 of the movable contact 13.
The outer surface shape of the second portion 12a ₂ is a regular polyhedron formed by combining three fan-shaped unit surfaces 12a ₂₃ of the same shape. Each unit surface 12a ₂₃ . . . three ridge lines 12a ₂₂ formed at mutually connecting portions extend so as to converge toward the tip. The intersection or convergence point formed by extending the three ridge lines 12a and ₂₂ is located on a line that extends perpendicularly to the bottom surface of the recess 10a and passes through the center point of the hole 14 of the movable contact 13. preferable.

Reference numeral 15 denotes an operating member that is disposed above the movable contact 13 and deforms the movable contact 13 when operated to move toward the bottom side of the recess 10a. This operating member 15 includes a tubular pressing part 15a having an inner diameter that can surround the hole 14 of the movable contact 13 in the center part of the lower surface side, and an annular flange facing the pressing part 15a via an annular groove. Part 15
b, and an operation section 15c that is touched by an operator's finger. The flange portion 15b has an outer diameter dimension such that it can smoothly slide within the space surrounded by the curved surface portions 10c1 to 10c4 of the inner circumferential surface of the recessed portion 10a.

Reference numeral 16 denotes a fixing plate provided to close the end face of the recess 10a on the opening side. At the center of this fixing plate 16, an operating portion 15 of the operating member 15 is provided.
A circular through hole 16a is formed into which the hole 16c loosely fits. The fixing plate 16 has fixing protrusions 18 provided at the four corners of the upper surface of the case body 10, as shown in FIG.
are inserted into mounting holes (not shown) provided at corresponding positions on the fixing plate 16, and then fixed by welding the protrusions 18.

In this embodiment, three ridge lines 12a ₂₂ are formed on the outer surface of the center contact 12a, which are evenly arranged and converge toward the tip. 12a, the peripheral edge of the hole 14 of the movable contact 13 comes into contact with the ridgeline 12a ₂₂ of the central contact 12a, forming three electrical contact parts. Therefore, as shown in FIG. 4, even if dirt or dust 7 is present in one of the contact portions, the remaining contact portions ensure conductivity, so there is little risk of poor contact occurring.

Note that the outer shape of the center contact 12a is not limited to the shape of the above embodiment, and assuming that there is no dirt or dust, the peripheral edge of the hole 14 will change when the movable contact 13 is deformed. It may have any shape as long as it contacts all the ridgelines. Preferably, a regular polyhedral shape such as a triangular pyramidal surface or a quadrangular pyramidal surface is used. It is sufficient that the polyhedral shape has at least two ridge lines. Further, the ridge line does not necessarily need to extend continuously from the bottom side to the convergence point, and it is sufficient that the ridge line exists at least in the portion that contacts the peripheral edge of the hole 14 of the movable contact 13. Therefore, it goes without saying that the center contact 12a may have a flat tip.

Further, the shape of the movable contact 13 and the shape of the hole 14 are not limited to the shapes of the above embodiments,
The movable contact may have any shape as long as it can be reversed. Further, the hole 14 is not limited to the through hole as in the above embodiment, but may be any hole as long as the portion that contacts the ridgeline of the center contact 12a has a substantially circular peripheral edge, for example, the recess 1
It may be a hole with a bottom that projects toward the opening of Oa.

[Effect of the invention] According to the invention, the shape of the peripheral edge of the hole of the movable contact is formed into a substantially circular shape, the central contact is made to protrude toward the hole of the movable contact, and the outer surface thereof is directed toward the tip. Since it is formed into a multifaceted shape with at least two converging ridgelines, it is possible to prevent poor contact due to local deformation of the hole of the movable contact, and at least the ridgeline formed on the outer surface of the center contact and the movable contact Two or more contact portions can be formed with the peripheral edge of the hole. Therefore, even if dust is present in one contact part, electrical contact can be maintained by the other contact parts, so that poor contact due to the intrusion of dust and dirt can be prevented. Furthermore, since the contact portion is formed on the ridgeline of the central contact point, there is an advantage that even if dirt or dust gets on the ridgeline, the dirt or dust will fall off naturally.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing one embodiment of the present invention;
The figure is a schematic plan view of the embodiment shown in Fig. 1, Fig. 3 is an explanatory diagram showing the shape of the side surface of the contact placed in the recess of the case body, and Fig. 4 is an illustration of the embodiment of the present invention in which dust is removed from the movable contact. 5 is a sectional view schematically showing the configuration of a conventional switch, and FIG. 6 is a movable contact used in a conventional switch. FIG. 10... Insulating case body, 10a... Recessed part, 12
a... Center contact, 12b ₁ and 12b ₂ ... End contact,
13... Movable contact, 14... Hole, 15... Operation member.

Claims (1)

[Claims for Utility Model Registration] (1) An insulating case body having a recess, a center contact and an end contact fixed in the recess of the case body, and a hole in the center and an end edge. a movable contact that is accommodated in the recess so as to be in contact with the end contact, and that is curved so that the central portion protrudes toward the opening of the recess, and that can be operated in reverse; and when operated, the movable contact In the push-on switch, the push-on switch includes an operating member that moves within the recess so as to bring the peripheral edge of the hole of the movable contact into contact with the central contact, wherein the peripheral edge of the hole of the movable contact has a shape It has a substantially circular shape, and the central contact protrudes toward the hole of the movable contact, and its outer surface has a polygonal shape having at least two ridge lines that converge toward the tip. A push-on switch featuring the following. (2) The convergence point of the at least two ridge lines of the polyhedral shape and the center point of the hole of the movable contact are located on the same line extending in a direction substantially perpendicular to the bottom surface of the recess. A push-on switch according to claim 1 of the utility model registration claim. (3) The push-on type switch according to claim 2, wherein the polyhedral shape is a regular polyhedral shape formed by connecting a plurality of unit faces of substantially the same shape.