JP2011003452A - Key switch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a key switch attaining longer lifetime by suppressing the performance deterioration of a structural member due to repeated use.SOLUTION: In a key switch is provided for switching on a plurality of switch parts 2, 3 stepwise in sequence with the pressing operation of a key 1 in one direction, the plurality of switch parts 2, 3 include the switch part 3 at a final stage and the switch part 2 at the other stage; and a switch mechanism 4 (a first operating body 5 and a second operating body 6) is provided for switching on the plurality of switch parts 2, 3, while applying depressing loads onto the switch parts 2, 3 in the mutually intersecting direction of the switch part 3 at the final stage and the switch part 2 at the other stage. This suppresses the performance deterioration of the switch part 2 at the other stage of the switch mechanism 4 due to repetitive use, in particular, the structural member such as a contact thereof and a contact depressing part 10 at the front end of an arm part of the first operating body 5 for switching on the switch part 2.

Description

  The present invention relates to a key switch for sequentially turning on a plurality of switch sections step by step by a single pressing operation.

Conventionally, as this type of key switch, there has been a multi-stage pushbutton switch described in Patent Document 1.
As shown in FIG. 5, when the key 125 is pressed, the side wall 126 of the first-stage switch 121 is first bent, the movable contact 128 and the fixed contact 129 come into contact, and the first-stage switch 121 is turned on. When the key 125 is further depressed, the side wall 127 of the switch 122 at the second stage is bent and the movable contact 131 and the fixed contact 130 come into contact (actually, the fixed contact 130 on the movable substrate 123 is lowered). That is, the eye switch 122 is turned on (see Patent Document 1).

JP-A-6-60773 (FIG. 1, [0013])

However, in the key switch described in Patent Document 1, a load is continuously applied to the first-stage switch (switch section other than the last stage) even when the second-stage switch (last-stage switch section) is pressed down, and increases. .
For this reason, in repeated use, performance deterioration of the first-stage switch, specifically, deformation such as deformation or the like in the rubber or contact portion constituting the first-stage switch easily occurs, and it is difficult to extend the life.

  The present invention has been made in view of the above circumstances, and in a pressing operation to reach the final stage switch section (second stage switch section in the case of a two-stage key switch), switch sections other than the final stage switch section. An object is to provide a key switch that eliminates an increase in load on the (first-stage switch portion in the case of a two-stage key switch) and can extend the service life.

In order to achieve the above object, according to the first aspect of the present invention, there is provided a key switch for sequentially turning on a plurality of switch sections stepwise by a one-way pressing operation of the key, wherein the plurality of switch sections are the last stage switches. And a switch unit other than the final stage, and the direction of the pressing load applied to the switch part when turning on the plurality of switch units is different between the switch part of the final stage and the switch part other than the final stage. And a switch mechanism.
According to a second aspect of the present invention, in the first aspect of the present invention, the switch mechanism is operated in a direction crossing the pressing direction of the key by a pressing operation in one direction of the key, and other than the final stage. A first action body that turns on the switch part, and a second action body that operates in the same direction as the pressing direction of the key by further pressing operation in one direction of the key to turn on the last-stage switch part, It is characterized by comprising.
According to a third aspect of the present invention, in the second aspect of the invention, the first action body includes a plurality of first action bodies, and each first action body is sequentially operated stepwise by a one-way pressing operation of the key. The switch units other than the final stage provided corresponding to the first acting bodies are sequentially turned on step by step.

In the invention according to claim 1, in the key switch that sequentially turns on the plurality of switch units stepwise by pressing the key in one direction, the direction of pressing load on the switch unit when turning on the plurality of switch units is finally determined. The switch part of the stage is different from the switch part other than the final stage. Therefore, according to the first aspect of the present invention, while the key pressing operation direction is common, the switch of the final stage is further operated by pressing the key after the switch parts other than the final stage are turned on by the key pressing operation. Even when the part is turned on, the pressing load on the switch parts other than the final stage is not increased. Thereby, it is possible to suppress the deterioration of the performance of the constituent members of the switch part, particularly the switch part other than the final stage in repeated use, and the key switch can have a long life.
According to the invention of claim 2, the key switch of claim 1 can be provided easily and at low cost.
According to the invention of claim 3, a multi-stage (three or more stages) key switch can be provided simply and at low cost.

It is sectional drawing of the key switch which concerns on one Embodiment of this invention. It is an exploded perspective view similarly. It is operation | movement explanatory drawing similarly. FIG. 4 is an enlarged view of a portion surrounded by a chain line in FIG. 3. It is sectional drawing of the conventional key switch.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, the same code | symbol shows the same or an equivalent part between each figure.
FIG. 1 is a cross-sectional view of a key switch according to an embodiment of the present invention, and FIG. 2 is an exploded perspective view of the key switch. In the present embodiment, a case where the present invention is applied to a two-stage key switch will be described.

As shown in FIGS. 1 and 2, the two-stage key switch according to the present embodiment has a first key 1 by a pressing operation in one direction of the key 1, in the illustrated example, a downward vertical direction (hereinafter simply referred to as a downward direction). This is a key switch for sequentially turning on the stage switch section (switch section other than the last stage) 2 and the second stage switch section (final stage switch section) 3 step by step.
This two-stage key switch determines the direction in which a pressing load is applied to the switch sections 2 and 3 (the pressing load direction) when the first-stage switch section 2 and the second-stage switch section 3 are turned on. The switch mechanism 4 is made different between the part 2 and the second stage switch part 3.

The switch mechanism 4 includes a first action body 5 and a second action body 6.
The first actuating member 5 is driven (actuated) in a direction intersecting the pressing direction of the key 1 by the pressing operation of the key 1 in the downward direction, in the illustrated example, in the right direction substantially orthogonal to the first actuating member 2. It is an action body to be turned on.
The first working body 5 includes a base portion 7 and an arm portion 8. The arm portion 8 extends a predetermined length downward from the base portion 7, the tip end portion is folded upward, and the contact pressing portion 10 is formed to protrude rightward. The arm portion 8 has flexibility in at least the extending direction (left and right direction in the figure). Usually, the entire first working body 5 including the base portion 7 and the arm portion 8 is formed of a synthetic resin having flexibility.
The second acting body 6 is an acting body that is deformed (actuated) in the same downward direction as the pressing direction of the key 1 by further pressing operation of the key 1 in the downward direction to turn on the second-stage switch portion 3. Yes, it is made of a rubber body that is almost inverted and has elasticity. A contact pressing portion 11 protrudes downward from substantially the center of the lower surface of a second working body (hereinafter also referred to as a rubber body) 6 corresponding to the reverse saddle-shaped saddle bottom.

In the present embodiment, the first stage switch unit 2 and the second stage switch unit 3 are each formed of a membrane switch. In this membrane switch, two synthetic resin thin plates having flexibility are opposed to each other with a small gap, and a contact is provided on the opposite surface of each synthetic resin thin plate, and the pressing force from the contact direction is received. In other words, a known sheet-like or film-like switch is configured so that the opposite contacts come into contact (ON).
In the illustrated example, the first-stage switch unit 2 and the second-stage switch unit 3 are electrically insulated from each other inside the single membrane switch body 12 and are configured separately.

The first-stage switch unit 2, the second-stage switch unit 3, and the switch mechanism 4 (first action body 5 and second action body 6) are as follows in the space formed by the upper case 13 and the lower case 14. Is housed in.
That is, a back plate 15 is disposed on the lower case 14 at an appropriate interval, and the rubber body 6 is fixed substantially at the center on the back plate 15, and a stem 16 is attached to the upper end surface of the rubber body 6. It is placed.
The stem 16 is formed of a rectangular lid-like lower step portion 17 and a substantially rectangular tube-like upper step portion 18 whose outer shape in plan view is slightly smaller than the lower step portion 17 and whose upper end surface extends slightly inwardly in a bowl shape. Then, it is placed on the upper end surface of the rubber body 6 at substantially the center of the lid surface of the lower step portion 17.
In addition, a polydome 19 is arranged and fixed almost at the center on the upper surface side of the lid surface of the lower stem portion 17 and is pressed against the lower surface of the base portion 7 when the first step switch portion 2 of the key 1 is operated (short stroke operation). In this way, the operator is given a click feeling.

At the position where the right side wall of the stem upper step 18 is in contact with or substantially in contact, the tip of the upright side 20 of the membrane switch body 12 fixed on the back plate 15 penetrates the lid surface of the stem lower step 17, It extends upward.
The first-stage switch unit 2 is built in the distal end portion of the upright side 20 of the membrane switch body 12, and the contact pressing portion 10 at the distal end of the arm portion 8 of the first acting body 5 is provided on the left side surface of the distal end portion. Are facing each other. The contact pressing portion 10 is opposed to a position where the contact pressing portion 10 is slightly in contact with the left side surface of the leading end portion (the portion including the first-stage switch portion 2) of the rising edge 20 of the membrane switch body 12 when the key 1 is not operated. ing.
Further, the planar portion 21 of the membrane switch body 12 including the second-stage switch portion 3 is positioned at a position facing the contact pressing portion 11 of the rubber body 6 on the back plate 15.

The chassis 22 is formed in a substantially rectangular tube shape extending in a bowl shape with the upper end surface slightly inward and the lower end surface slightly outward, and is fixed on the back plate 15. The inside 22 is accommodated in a telescopic manner so as to be movable up and down.
The chassis 22 is fixed on the back plate 15 with, for example, screws 23 in a state where the stem 16 placed on the upper end surface of the rubber body 6 is accommodated as described above.

The upper case 13 is formed in a substantially square frame shape with a square hole 25 through which the operation portion 24 of the key 1 can be inserted, and a boss portion 26 extending downward is projected on the left and right sides of the lower case. ing.
The lower case 14 has a boss portion 27 projecting upward at a position corresponding to the boss portion 26 of the upper case 13 on the flat plate portion, and between the boss portions 26 and 27 of the upper and lower cases 13 and 14. The upper case 13 is integrated with a screw 28 through a screw hole that communicates therewith. At this time, the back plate 15 is sandwiched between the boss portions 26 and 27 of the upper and lower cases 13 and 14 and fixed at a fixed position between the upper and lower cases 13 and 14.
A cylindrical support portion 29 that receives a pressing force applied to the rubber body 6 when a switch is operated protrudes from a position corresponding to the rubber body 6 on the back plate 15 on the upper surface of the lower case 14. The height of the support portion 29 is the same as the height of the boss portion 27 protruding from the upper surface of the lower case 14.

The key 1 includes a square lid-like operation part 24 and a stopper part 30 that extends slightly outward from the lower end surface of the operation part 24 in a bowl shape. The operation part (key operation part) 24 is inserted into the square hole 25 of the upper case 13 from below, and the stopper part 30 prevents the key 1 from coming out of the square hole 25.
Near the center of the lower surface of the key operation unit 24, an operation connection unit 31 that transmits the pressing operation of the key 1 to the base unit 7 of the first acting body 5 is provided. The operation connecting portion 31 only has to transmit the operation movement (vertical movement) of the key 1 to the base portion 7 and is connected to the base portion 7 so as not to restrain the movement of the arm portion 8. The base portion 7 is connected to the operation connecting portion 31 with the arm portion 8 extending to the right side in the drawing.
Further, the operation connecting portion 31 is formed with a protruding portion 31a so that a force is always applied to the arm portion 8 side when the base portion 7 is pressed.

The coil spring 32 allows the downward pressing operation of the key 1 while applying an appropriate reaction force, and when the pressing is released, the return force for automatically returning the key 1 to the original non-operation position. It is an elastic member that gives The coil spring 32 is interposed between the lower surface of the key operation portion 24 and the hook-shaped extension portion 33 on the upper end surface of the chassis 22 using two boss portions 34 and 35. The boss portions 34 and 35 position the coil spring 32 and prevent the coil spring 32 from being detached from the position.
The upper limit value of the pressing operation amount (stroke amount) of the key 1 is determined by the distance setting value from when the key 1 is pressed until the lower end surface of the lower stem portion 17 contacts the upper surface of the back plate 15. This value does not exceed the height dimension of the key operation portion 24 that protrudes from the upper surface of the upper case 13 when not operated, and the key operation portion 24 does not exceed the upper case 13 even when the key 1 is pressed to the maximum. It does not come off from the square hole 25 downward.

Note that FIG. 2 is a diagram in which the constituent members are shown downward in order from the constituent members shown in the upper part in FIG. 1. For this reason, the key 1 is located above the upper case 13 in FIG. 2, but if the position of the stopper portion 30 of the key 1 is used as a reference (following the procedure for assembling the key 1 into the upper case 13), In FIG. 2, the key 1 is located below the upper case 13. The first action body 5 is located below the key 1.
Further, the key 1, the base 7 (first action body 5), the upper case 13, the polydome 19, the chassis 22, the stem 16, the rubber body (second action body) 6, the back plate 15 and the lower case 14 in a plan view. It goes without saying that the central positions of the are aligned.

Next, the operation of the two-stage key switch shown in FIG. 1 will be described with reference to FIGS. 3 (a) to 3 (c).
3A shows an initial state (when not operated), FIG. 3B shows a time when the first stage switch unit 2 is turned on, and FIG. 3C shows a state when the second stage switch unit 3 is turned on.
Now, from the initial state shown in FIG. 3 (a), when the key 1 is pressed downward (short stroke operation) as shown by the arrow A in the figure, the switch mechanism 4 is configured as shown in FIG. 3 (b). The first-stage switch unit 2 is turned on by the pressing action of the first acting body 5 to the right.
That is, when the key 1 is pressed, the base portion 7 of the first action body 5 is lowered by the operation connecting portion 31, and accordingly, the distal end portion of the arm portion 8 moves in the right direction. Then, the contact pressing portion 10 at the tip of the arm portion 8 presses the opposing contact built in the tip of the upright side 20 of the membrane switch body 12 in the right direction that is the contact opposing direction, that is, the first contact switch portion 2. Turn on.
FIG. 4 shows an enlarged view of the on-operation of the first stage switch unit 2, and an arrow “a” in the figure indicates a contact pressing unit at the tip of the arm unit 8 when the first stage switch unit 2 is turned on. 10 moves are shown.

Since the pressing operation amount of the key 1 when the first-stage switch unit 2 is turned on is small, the amount of downward deformation (operation amount) of the second acting body 6 is small at this time, and the contact pressing unit 11 is lowered. Since the amount is small, the second stage switch unit 3 cannot be turned on.
The amount of pressing operation of the key 1 when the first-stage switch unit 2 is turned on is small, and the reaction force to the key 1 is also small. At this time, the polydome 19 gives a feeling of clicking operation to the operator.

When the key 1 is further pressed downward as shown by the arrow A in the figure from the ON state of the first-stage switch unit 2 shown in FIG. 3B, as shown in FIG. The second stage switch unit 3 is turned on by the downward pressing action of the second action body 6 constituting the switch mechanism 4.
That is, when the key 1 is further pressed (full stroke operation), the stem 16 is lowered via the operation connecting portion 31, the base portion 7 of the first action body 5 and the polydome 19, and accordingly, the second action body. 6 is deformed (actuated) so as to be crushed downward. And the contact pressing part 11 of this 2nd action body 6 presses the opposing contact incorporated in the plane part 21 of the membrane switch body 12 to the downward direction which is a contact opposing direction, and mutually contacts, ie, the 2nd step switch part 3 Turn it on.

The second actuating member 6 is based on the material (rubber) and shape (inverted saddle shape), and gives a feeling of clicking operation to the operator by deformation caused by the downward pressing force. Turn on. When the stroke amount of the key 1 necessary to turn on the second stage switch portion 3 is reached, the lower end surface of the stem lower step portion 17 comes into contact with the upper surface of the back plate 15, and in other words, below the stem 16, in other words, lower than that of the key 1. Movement to is regulated.
The downward movement of the stem 16 accompanying the pressing operation of the key 1 is performed while the rotation around the movement center axis is prevented in the chassis 22.

When the second-stage switch unit 3 is turned on, the key 1 moves downward until it is regulated as described above, and thus the base unit 7 of the first action body 5 is also lowered. However, as can be seen from FIGS. 3B and 3C, at this time, there is almost no movement of the tip of the arm portion 8 of the first acting body 5 in the further right direction (arrow A in FIG. 4). Therefore, the pressing load (pressing force) on the first-stage switch unit 2 by the tip of the arm unit 8 is not increased.
Such an operation can be easily executed by the switch mechanism 4 that makes the direction of the pressing load applied to the first stage switch unit 2 and the second stage switch unit 3 different, that is, 90 ° different in the illustrated example.
In the conventional key switch, as can be seen from FIG. 5, when the second-stage switch 122 is depressed (corresponding to when the second-stage switch section 3 is turned on), the first-stage switch 122 (first-stage switch section). A configuration that does not increase the load applied to 2) is difficult.

  When the key 1 is released only by turning on the first-stage switch unit 2 or when the first-stage switch unit 2 and the second-stage switch unit 3 are continuously turned on, the key 1 is released. In either case, the state shown in FIG. 3B or the state shown in FIG. 3C is restored to the initial state shown in FIG. Similarly to the return of the key 1, the first action body 5 and the second action body 6 also return to the initial state shown in FIG. 3A from the state shown in FIG. 3B or the state shown in FIG. To do. The returning operation to the initial state is based on the restoring force of the rubber body 6 and the coil spring 32.

As described above, according to the present embodiment, in the key switch for sequentially turning on the two-stage switch units 2 and 3 stepwise by one pressing operation, the first-stage switch unit 2 and the second-stage switch unit 3 are used. When turning on, the pressing load directions applied to these switch portions 2 and 3 were varied by approximately 90 °.
Therefore, according to the present embodiment, while the pressing operation direction of the key 1 is common to one direction, for example, the downward direction, the key 1 is further pressed after the first-stage switch portion 2 is turned on by the pressing operation of the key 1. Even when the second stage switch unit 3 is turned on by operation, the pressing load on the first stage switch unit 2 is not increased. [In the state shown in FIG. 3 (b), the pressing load applied to the first-stage switch unit 2 is fully applied, and does not change in the state shown in FIG. 3 (c). ]

  Therefore, even in repeated use, constituent members such as the membrane switch (opposing contact) constituting the first stage switch unit 2 and the contact pressing unit 10 at the tip of the arm unit 8 constituting the action body 5 of the first stage switch unit 2 Deterioration of performance, specifically, defects such as deformation are less likely to occur, and the life of the key switch can be extended.

  3 (b) and FIG. 3 (c) are the same aspects, while FIG. This is because the first action body 5 is not displaced in the state shown in FIGS. 3B and 3C, and the position of the arm portion tip (contact pressing portion 10) in the left-right direction is not changed. It shows that the pressing load on the first stage switch unit 2 by the first acting body 5 is not increased.

In the present embodiment, the two-stage key switch for sequentially turning on the two switch parts stepwise by the downward pressing operation of the key 1 has been described. However, the present invention can be applied to three or more switch parts in stages. It may be applied to a multi-stage key switch that is sequentially turned on.
In this case, for example, a multi-stage switch section is provided as a switch section other than the last stage, and the length of the arm part of each operating body that turns on each switch section, the degree of flexibility, etc. The plurality of switch sections are sequentially turned on according to (stroke amount). The configuration of the last-stage switch unit is not particularly different from the above-described embodiment.
Moreover, in this embodiment, although each switch part was comprised by the membrane switch, as long as it is the structure turned on by the action | operation (driving, deformation | transformation, etc.) of an action body, any may be sufficient. For example, a tact switch (trade name) may be used for each switch unit.

  1: key, 2: first-stage switch section (switch section other than final stage), 3: second-stage switch section (final stage switch section), 4: switch mechanism, 5: first acting body, 6: first 2 action bodies (rubber bodies), 7: base, 8: arm part, 10, 11: contact pressing part.

Claims (3)

In a key switch that turns on a plurality of switch sections step by step by pressing the key in one direction,
The plurality of switch units include a switch unit at the final stage and a switch unit other than the final stage,
A key mechanism comprising: a switch mechanism in which a direction of a pressing load applied to the switch unit when the plurality of switch units are turned on is different between the switch unit at the final stage and the switch units other than the final stage. switch. The switch mechanism is
A first acting body that operates in a direction crossing the pressing direction of the key by a pressing operation in one direction of the key to turn on a switch unit other than the final stage;
A second action body that is actuated in the same direction as the pressing direction of the key by further pressing operation in one direction of the key to turn on the last-stage switch unit;
The key switch according to claim 1, wherein the key switch is provided. A plurality of the first acting bodies;
Each first operating body is sequentially operated stepwise by a one-way pressing operation of the key so as to sequentially turn on switch units other than the last stage provided corresponding to each first operating body. The key switch according to claim 2, wherein the key switch is configured as follows.

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