JP2009146763A - Switch device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a switch device having a switch operation shaft that causes less hitting sound (noise) and shock in the operation of restoring the switch to its initial state, and that has high mechanical reliability. <P>SOLUTION: One end of a body 10 made of a thermoplastic hard resin is formed in an undercut shape having a neck 10a and a head 10b that is connected to the neck 10a and larger than the outer diameter of the neck 10a. The end of the body including the undercut-shaped part is formed of an elastomer as an elastic part 11 by insert molding or two color molding. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a switch device, and more particularly to a switch device having an improved switch operation shaft constituting an ON / OFF operation mechanism of a switch.

  Conventionally, switch devices having various mechanisms and operations have been put to practical use in connection / disconnection of electrical conduction paths, and the seesaw switch shown in FIG. 3 is one of them.

  The seesaw switch 50 has switch operation shafts 52a and 52b slidably disposed on a pair of push-down switches (for example, tact switches) 51a and 51b arranged side by side, and is swingably supported by a peristaltic shaft 53. And a pair of protrusions 55a and 55b provided on the operation knob 54 are in contact with the upper end surfaces of the respective switch operation shafts 52a and 52b.

  Then, by swinging the operation knob 54 toward one of the tact switches 51a with the peristaltic shaft 53 as a fulcrum, the switch operation shaft 52a is pressed down via the protrusion 55a on the swing side of the operation knob 54. The key top 56a of the tact switch 51a that is in contact with the lower end surface of the switch operating shaft 52a that has been pressed is pressed, and the internal contacts of the tact switch 51a come into contact with each other by the pressed key top 56a so that the switch state is turned on. Switch operation.

  However, specifically, there are those having various operation modes. When the swing operation force of the operation knob 54 is released from the switch ON state, the switch operation shaft 52a is pushed up by the restoring force of the tact switch 51a, and any tact In some cases, the switches 51a and 51b also hold the non-operation state (initial state) in which they are turned off.

  In this case, in the switch ON state, the switch operation shaft 52b located on the opposite side to the pressed switch operation shaft 52a is in a state of being separated from the protrusion 55b of the operation knob 54, and the switch operation accompanying the release of the swing operation force is performed. The operating knob 54 performs a swinging motion about the swinging shaft 53 by the pushing force of the shaft 52a, and the protrusion 55b of the operating knob 54 contacts the upper end surface of the switch operating shaft 52b.

  Then, there is a concern that a hitting sound or an impact is generated when the projection 55b of the operation knob 54 and the upper end surface of the switch operation shaft 52b are in contact with each other, and the switch operator is uncomfortable.

Therefore, in order to solve such a problem, as shown in FIG. 4, a contact force (impact force) absorbing member 57 such as a soft resin is provided on the side of the switch operation shaft 52 where the projection 55 of the operation knob 54 contacts. A method is proposed in which the impact at the time of contact of the projection 55 of the operation knob 54 with the upper end surface of the switch operation shaft 52 is absorbed by the soft resin portion to suppress the occurrence of hitting sound and impact. (For example, refer to Patent Document 1).
JP 2004-146128 A

  However, the switch operating shaft 52 configured as described above is buckled and deformed when the absorbing member 57 receives a compressive load due to an impact at the time of contact of the projection 55 of the operation knob 54, thereby forming the switch operating shaft 52. Separation occurs at the boundary surface 59 between the absorbing member 57 and the portion 58 other than the absorbing member, and in the worst case, the absorbing member 57 may fall off the switch operation shaft 52.

  Therefore, it is possible to form the entire switch operating shaft with an impact absorbing member. In this case, however, the switch operating shaft needs to have a large diameter to prevent buckling because the strength of the switch operating shaft is weakened. Yes, it is difficult to handle when a long switch operating shaft is required.

  The present invention was devised in view of the above problems, and the object of the present invention is to perform switch operation with low mechanical noise (noise) and impact during restoration operation of the switch to the initial state and high mechanical reliability. A switch device having a shaft is provided.

In order to solve the above problems, the invention described in claim 1 of the present invention includes a pair of push-down switches arranged in parallel,
A substantially columnar switch operating shaft slidably housed inside a substantially cylindrical operating shaft guide portion formed in the housing on the push-down switch;
The operation knob is located above the switch operation shaft and is supported on the slide shaft so as to be swingable in a seesaw shape with the slide shaft as a fulcrum.
By applying a pressing force directed to the push-down switch on either side of the operation knob across the sliding shaft, the displacement due to the sliding of the operation knob is positioned downward via the switch operation shaft. Depressing the push-type switch to turn it on,
When the pressing force is removed, the repulsive force of the push-down switch raises the switch operation shaft located above the push-down switch and returns to the initial state in which any push-down switch is turned off. A switch device to perform,
The switch operating shaft is characterized in that the push-down switch side is formed with a hard portion and the operation knob side is formed with an elastic portion, and the elastic portion is supported by an undercut shape portion of the hard portion.

  The invention described in claim 2 of the present invention is characterized in that, in claim 1, the elastic portion is formed by insert molding or two-color molding in an undercut shape portion of the hard portion. It is.

  The invention described in claim 3 of the present invention is characterized in that, in any one of claims 1 and 2, the hard portion is made of a thermoplastic hard resin, and the elastic portion is made of an elastomer. Is.

  According to a fourth aspect of the present invention, in any one of the first to third aspects, the push-down switch is a tact switch.

  It is interposed between a pair of push-type switches arranged side by side and an operation knob supported so as to be swingable in the form of a seesaw. The switch operating shaft has the function of transmitting the repulsive force when the push-type switch shifts to the OFF state by removing the pressing force to the knob and returning the operation knob to the initial state. The side was formed with an elastic part, and the elastic part was supported by the undercut shape part of the hard part by insert molding or two-color molding.

  As a result, it has become possible to realize a switch device having a switch operation shaft that has less mechanical noise and impact during the operation of restoring the switch to the initial state and has high mechanical reliability. There is an effect.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to FIG. 1 and FIG. 2 (the same parts are given the same reference numerals). The embodiments described below are preferable specific examples of the present invention, and thus various technically preferable limitations are given. However, the scope of the present invention particularly limits the present invention in the following description. Unless stated to the effect, the present invention is not limited to these embodiments.

  1A to 1C are explanatory views showing the structure and operation of the switch device of the present invention. Among these, (a) and (c) show the non-operating state (initial state) of the switch device.

  A pair of push-down switches (for example, tact switches) 2a, 2b are arranged side by side on the substrate 1, switch operation shafts 3a, 3b are disposed on the key tops 2aa, 2ba of the respective tact switches 2a, 2b, and keys The upper surfaces 2ab and 2bb of the tops 2aa and 2ba are in contact with the lower end surfaces 3ac and 3bc of the switch operation shafts 3a and 3b.

  The respective switch operation shafts 3 a and 3 b are slidably accommodated in cylindrical operation shaft guide portions 4 a and 4 b provided in the housing 4, and their upper end surfaces 3 ab and 3 bb swing on the swing shaft 12. It is in a state of being in contact with the lower end surfaces 5ac and 5bc of the pair of protrusions 5a and 5b provided on the operation knob 5 that is movably supported.

  In this state, both the tact switch 2a and the tact switch 2b are in the OFF state.

  As shown in the cross-sectional view of FIG. 2, the switch operation shafts 3a and 3b have a main body 10 made of a thermoplastic hard resin such as polycarbonate resin, and a rubber or polymer resin at one end of the main body 10. The elastic portion 11 is formed by insert molding or two-color molding using an elastomer such as. At this time, the end portion of the body portion 10 where insert molding or two-color molding is performed has a neck portion 10a and a head portion 10b that is connected to the neck portion 10a and is larger than the outer diameter of the neck portion 10a, and the neck portion of the head portion 10b. The surface 10c on the 10a side has an undercut shape that converges toward the neck 10a.

  Therefore, even when a compressive load is applied to the elastic portion 11 and buckling deformation occurs, the elastic portion 11 is supported by the head portion 10b and the neck portion 10a, so that the amount of deformation is small, and the elastic portion 11 is It does not fall off easily from the end, and has a highly reliable structure with excellent mechanical strength.

  Returning to FIG. 1B, when a pressing force directed downward (in the direction of the tact switch 2 a) is applied from the swing shaft 12 to the one tact switch 2 a side of the operation knob 5, The protrusion 5a is lowered, the key top 2aa of the tact switch 2a is pushed down via the switch operation shaft 3a, the internal contacts (not shown) of the tact switch 2a come into contact with each other, and the tact switch 2a is turned on.

  At this time, the other tact switch 2b side of the operation knob 5 from the rocking shaft 12 rises in the opposite direction to the tact switch 2b side with the rocking shaft 12 as a fulcrum, and accordingly, the protrusion 5b of the operation knob 5 also moves. Similarly rises.

  Then, since the switch operation shaft 3b is positioned on the key top 2ba of the tact switch 2b, a gap 13 is formed between the upper end surface 3bb of the switch operation shaft 3b and the lower end surface 5bc of the projection 5b of the operation knob 5. The tact switch 2b is in the OFF state.

  Next, as shown in FIG. 1C, when the pressing force applied to the operation knob 5 is removed, the internal contacts are separated from each other by the repulsive force of the internal contacts of the tact switch 2a, and the tact switch 2a is turned off. Become. At the same time, the key top 2aa of the tact switch 2a is pushed upward, the switch operating shaft 3a located on the key top 2aa, and the protrusion 5a located on the switch operating shaft 3a. 12, the part on the tact switch 2a side rises.

  Then, the state returns to the same state as in FIG. 1A, that is, the switch device is not operated (initial state), and both the tact switch 2a and the tact switch 2b are turned off.

  At this time, the push-up force applied to the portion on the tact switch 2a side from the swing shaft 12 of the operation knob 5 is moved to the portion on the tact switch 2b side opposite to the tact switch 2a across the swing shaft 12. 12 acts as a moment toward the bottom (in the direction of the tact switch 2b) with the fulcrum 12 as a fulcrum, and the part of the operation knob 5 on the tact switch 2b side from the swinging shaft 12 descends, and the projection 5b also descends.

  The lowered protrusion 5b collides with the upper end surface 3bb of the switch operating shaft 3b forming a gap with the lower end surface 5bc of the protrusion 5b when the tact switch 2a is in the ON state.

  The collision speed when the projection 5b of the operation knob 5 collides with the upper end surface 3bb of the switch operation shaft 3b is determined by the repulsive force of the internal contact through the key top 2aa of the tact switch 2a. Along with this, the impact force that the switch operating shaft 3b receives from the protrusion 5b also increases.

  In any case, the upper end surface 3bb of the switch operation shaft 3b is still subjected to an impact by the projection 5b of the operation knob 5, but the switch operation shaft 3b is made of a rigid thermoplastic as described with reference to FIG. The upper end surface of the switch operating shaft 3b is composed of a main body 10 made of resin and an elastic portion 11 formed by insert molding or two-color molding with an elastomer at one end of the main body 10 and the projection 5b collides with it. 3bb is included in the elastic part 11.

  Therefore, the impact caused by the projection 5b of the operation knob 5 is absorbed by the elastic portion 11 of the switch operation shaft 3b, and the hitting sound and impact are suppressed, so that the switch operator is hardly given a sense of incongruity.

  Similarly, from the explanation based on FIG. 2, the structure of the switch operating shaft 3b is such that one end of the main body 10 formed of a thermoplastic hard resin is connected to the neck 10a and the neck 10a. It has an undercut shape having a head portion 10b larger than the diameter, and an end portion of the main body portion 10 including the undercut shape portion is formed into an elastic portion 11 by insert molding or two-color molding with an elastomer. It has become.

  Therefore, even if the elastic portion 11 is subjected to a buckling deformation due to the impact of the projection 5b of the operation knob 5, the end portion of the main body portion 10 that supports the elastic portion 11 has an undercut shape, so that the elastic portion 11 is elastic. The part 11 is not easily detached from the main body part 10, and a switch operation shaft with high mechanical reliability is realized.

  In addition, since a part of the switch operation shaft 3b is formed of an elastic member, the amount of buckling deformation is smaller than when the entire switch operation shaft is formed of an elastic member. Therefore, there is no need to particularly increase the diameter of the switch operation shaft.

  Therefore, it is possible to maintain a diameter equivalent to that of a conventional switch operation shaft in which the entire switch operation shaft is formed of a thermoplastic hard resin.

  Further, since the sliding portions (main body portions) of the switch operating shafts 3a and 3b that slide in the operating shaft guide portions 4a and 4b of the housing 4 are made of a thermoplastic hard resin having a low frictional resistance, the operating shaft guide portions It is not necessary to provide a mechanism for suppressing friction when the switch operating shafts 3a and 3b slide on the 4a and 4b, and the switch device can be downsized.

  The above description is based on the ON / OFF operation of one tact switch 2a of the pair of tact switches 2a, 2b, but the same applies to the case based on the ON / OFF operation of the other tact switch 2b. The explanation is omitted because it exists.

It is explanatory drawing which shows the structure and operation | movement of a switch apparatus of this invention. It is sectional drawing of the switch operation shaft which concerns on the switch apparatus of this invention. It is a fragmentary sectional view of the switch apparatus of a prior art example. It is sectional drawing of the switch operation shaft which concerns on the switch apparatus of a prior art example.

Explanation of symbols

1 substrate 2a tact switch 2aa key top 2ab top surface 2 tact switch 2b tact switch 2ba key top 2bb top surface 3 switch operation shaft 3a switch operation shaft 3ab upper end surface 3ac lower end surface 3b switch operation shaft 3bb upper end surface 3bc lower end surface 4 housing 4a operation shaft Guide portion 4b Operation shaft guide portion 5 Operation knob 5a Projection portion 5ac Lower end surface 5b Projection portion 5bc Lower end surface 10 Body portion 10a Neck portion 10b Head portion 10c Surface 11 Elastic portion 12 Oscillating shaft 13 Gap

Claims (4)

A pair of push-type switches arranged side by side;
A substantially columnar switch operating shaft slidably housed inside a substantially cylindrical operating shaft guide portion formed in the housing on the push-down switch;
The operation knob is located above the switch operation shaft and is supported on the slide shaft so as to be swingable in a seesaw shape with the slide shaft as a fulcrum.
By applying a pressing force directed to the push-down switch on either side of the operation knob across the sliding shaft, the displacement due to the sliding of the operation knob is positioned downward via the switch operation shaft. Depressing the push-type switch to turn it on,
When the pressing force is removed, the repulsive force of the push-down switch raises the switch operation shaft located above the push-down switch and returns to the initial state in which any push-down switch is turned off. A switch device to perform,
The switch operating shaft is characterized in that the push-down switch side is formed with a hard portion and the operation knob side is formed with an elastic portion, and the elastic portion is supported by an undercut shape portion of the hard portion.   The switch device according to claim 1, wherein the elastic portion is formed by insert molding or two-color molding in an undercut shape portion of the hard portion.   The switch device according to claim 1, wherein the hard portion is made of a thermoplastic hard resin, and the elastic portion is made of an elastomer.   The switch device according to claim 1, wherein the push-type switch is a tact switch.

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