JP2003086048A - Key switch device, keyboard equipped with key switch device, and electronic apparatus equipped with keyboard - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a key switch device whereby a key can be operated with an excellent feeling of clicking when operating a key top, the feeling of clicking can be freely designed, and accordingly the cost of the entire key switch device can be reduced while keeping depressing characteristics of the key top constant for a long time, without requiring a rubber spring and a complicated key top energizing mechanism widely used for a key switch device, a keyboard equipped with the key switch device, and an electronic apparatus equipped with the keyboard. SOLUTION: A cam face 25A is formed on a second cam part 24B, and another cam face 25A abutting on a linear and point-like abutting part to the cam face 25A of the second cam part 24B at an acute angle in a plan view and having a slant face 60 is formed on a first cam part 24A. In addition, a gap 63 opened toward the fixed point 64 side of a torsion spring 33 from the abutting part is provided between the cam face 25A of the second cam part 24B and the slant face 60.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a key switch device for performing a switching operation while guiding a vertical movement of a key top through a pair of link members, a keyboard equipped with the key switch device, and an electronic device equipped with the keyboard. With regard to the key switch device, in particular, it is possible to perform a key operation with a good click feeling at the time of operating the key top without requiring a rubber spring or a complicated key top urging mechanism that is commonly used in a key switch device. At the same time, it is possible to freely design the click feeling, so that it is possible to reduce the cost of the entire key switch device while keeping the key top pressing characteristics constant for a long period of time. The present invention relates to a keyboard including a switch device and an electronic device including the keyboard.

[0002]

2. Description of the Related Art Heretofore, various devices have been proposed as a key switch device for a keyboard attached to a notebook personal computer, which is a kind of electronic equipment, in accordance with the downsizing and thinning of the personal computer. In this type of key switch device, the key top is biased upward to hold the key top in the non-pressed position, and when the key top is pressed, the key top buckles while performing a switching operation with a click feeling, and A rubber spring is commonly used to return the key top to the non-pressed position after switching.

The rubber spring is made of silicon rubber, EPDM rubber, or the like, but it is generally expensive, and the work of properly assembling it while positioning it at a predetermined position in the key switch device is not possible. It is complicated. Furthermore, when a rubber spring is used, the switching characteristics of the key switch device largely depend on the characteristics of the rubber spring, so that it is difficult to freely change the switching characteristics of the key switch device.

Under these circumstances, various proposals have recently been made to realize a key switch device without using a rubber spring. For example, Japanese Patent Laid-Open No. 10-172
In Japanese Patent No. 380, a pair of a first link and a second link are movably arranged between a hook of a key top and a hook of a base mold to guide vertical movement of the key top by each link, A key switch device in which a rubber sheet is stretched between the connecting portions of the links is described.

In such a key switch device, the circular projection formed on the back surface of the key top is in close contact with the rubber sheet when the key top is not pressed, and the key top is held in the non-pressed state. By pressing downward while increasing the tension of the rubber sheet via the circular protrusion, the circular protrusion and the rubber sheet are projected downward from the through hole, so that the switch area of the membrane sheet supported by the bottom plate with a click feeling To switch.
When the depression of the key top is released, the key top is moved upward by the elastic force of the rubber sheet and returns to the original non-depression position.

In the key switch device described in Japanese Patent Laid-Open No. 10-172380, since the rubber spring is not used, the degree of freedom in designing the key switch device is increased without being affected by the size of the rubber spring. It is possible to

[0007]

However, in the above-mentioned key switch device, although a generally used rubber spring is not used, only the rubber spring is replaced with a rubber sheet, which is a key switch device. Since a rubber sheet is required,
It is still insufficient to reduce the cost of the entire key switch device, and the work of tensioning the rubber sheet between the connecting portions of the pair of links complicates the work of assembling the key switch device. . Further, although it is possible to perform a switching operation with a click feeling when the key top is pressed, it is extremely difficult to freely design such a click feeling.

Although a key switch device has been proposed in the past, which is configured to urge the key top upward through an elastic member made of resin instead of the rubber spring or the rubber sheet, the key switch device is made of such resin. The elastic member is advantageous in terms of cost because it can be integrally formed with the resin member that constitutes the key switch device, but when it is used for a long period of time, the elastic member is worn or repeatedly loaded. There is a possibility that a creep phenomenon may occur due to the stress that occurs and plastic deformation occurs. When the elastic member is worn or plastically deforms as described above, the pressing characteristic of the key top is changed, and the key operability is deteriorated. Further, if wear or plastic deformation of the elastic member further progresses, it is no longer possible to elastically support the vertical movement of the key top, and in some cases, the key switch device may not function due to breakage or the like.

The present invention has been made in order to solve the above-mentioned problems in the prior art, and does not require a rubber spring or a complicated key top urging mechanism which is generally used in a key switch device, and the key top It is possible to perform key operation with a good click feeling at the time of operation, and it is possible to design the click feeling freely, so that it is possible to keep the key top pressing characteristics constant for a long period of time. An object of the present invention is to provide a key switch device capable of reducing the cost of the entire switch device, a keyboard including the key switch device, and an electronic device including the keyboard.

[0010]

To achieve the above object, a key switch device according to a first aspect of the present invention comprises a key top and a pair of first and second link members movably arranged below the key top. And a first cam portion formed on the first link member in the key switch device for performing the switching operation of the switch portion while guiding the vertical movement of the key top through the first and second link members, A second cam portion that is formed on the second link member and faces the first cam portion, and supports at least one of the first cam portion and the second cam portion, and the first link member or the second link member A cantilever member in which the one cam portion is supported in a direction in which the cantilever member extended in a cantilever shape from the link member and the first cam portion and the second cam portion are in contact with each other. And an urging member for elastically urging The first cam portion and the second cam portion are in contact with each other at the contact portion, and the first cam portion and the second cam portion are in contact with each other via the biasing member as the switching operation is repeated. It has a shape such that the point of application of the urging force acting on the urging member shifts toward the predetermined fixed point side of the urging member.

According to another aspect of the key switch device of the present invention, one of the first cam portion of the first link member and the second cam portion of the second link member is separated from the first link member or the second link member. Since the cantilever member extended in a cantilever shape is supported, and the cantilever member is urged by the urging member in the direction in which the first cam portion and the second cam portion contact each other, While maintaining the contact state between the first cam portion of the first link member and the second cam portion of the second link member, the key top is moved upward by the cooperation of the biasing members that bias the cantilever member. It is possible to urge and hold the key top in the non-depressed position, and to return the key top to the non-depressed position when the depression is released. Therefore, it is possible to reduce the cost by configuring the key switch device without using a rubber spring or a complicated biasing mechanism. Further, the first cam portion and the second cam portion are
By biasing the cantilever beam member via the biasing member, the cantilever member is always in contact, and the contact position changes according to the vertical movement of the key top, so the first cam portion and the second cam portion. By changing the shape of the part as necessary, it is possible to freely design the click feeling generated when the key is operated.

Further, by elastically biasing the cantilever member via the biasing member, one cam portion of the first cam portion or the second cam portion supported by the cantilever member is made to move to the other. Although it is made to contact with the cam portion, the elastic force for contacting the first cam portion and the second cam portion with each other is expressed based on the elastic force of the cantilever member and the elastic force of the biasing member. To be done. At this time, the switching operation is repeatedly performed by the switch section based on the pressing operation of the key top, so that the contact portion between the first cam section and the second cam section is worn and the cantilever member is urged through the biasing member. Even when the initial urging force exerted on the first cam portion and the second cam portion is repeatedly performed by the switch portion, the first cam portion and the second cam portion are connected to the first cam portion and the second cam portion through the urging member. The point of action of the biasing force acting on the contact portion of the cam portion has a shape that shifts toward the predetermined fixed point side of the biasing member, and the point of action of the biasing force is the fixing point of the biasing member. Since it approaches the side, the biasing force exerted on the cantilever member via the biasing member becomes large. As a result, the decrease in the initial urging force of the urging member caused by the abrasion of the contact portion between the first cam portion and the second cam portion is due to the point of action of the urging force at the contact portion of the urging member. As they approach the fixed point side, they will be offset by the increase in the biasing force. Therefore, even when the switching operation is repeated over a long period of time, it is possible to reliably prevent and significantly stabilize the key top pressing characteristics, and ensure a stable switching operation for a long period of time. It becomes possible to do. Further, even when the elastic force of the cantilever member is reduced by repeatedly performing the switching operation, as described above, the action of the urging force by the urging member is exerted at the contact portion between the first cam portion and the second cam portion. As the point approaches the fixed point side of the biasing member, the biasing force exerted on the cantilever member via the biasing member increases, so the elastic force of the cantilever member is increased by the increased biasing force. It is possible to compensate for the decrease in the key top, and this also makes it possible to stabilize the pressing characteristic of the key top.

A key switch device according to a second aspect is the key switch device according to the first aspect, wherein the urging member is arranged on the first or second link member on which the cantilever member is formed. It is characterized in that an arrangement portion is provided. As described above, in the key switch device according to the second aspect, since the first link member or the second link member is provided with the disposing portion for disposing the urging member, the urging member may be the first link member or the first link member. The two link members can be integrally incorporated, and as a result, the entire key switch device can be made compact.

Further, in the key switch device according to a third aspect of the present invention, in the key switch device according to the second aspect, the biasing member faces the first arm portion and the first arm portion abutting the cantilever member. It is composed of a torsion spring having a second arm portion, and the arrangement portion has a first holding portion for holding the first arm portion and a second holding portion for holding the second arm portion. In the key switch device according to claim 3, a torsion spring having a first arm portion and a second arm portion is used as the urging member, and the first arm portion is connected to the second holding portion of the disposing portion. Is held via the second holding portion, and the first arm portion and the second arm portion that exert mutually biasing forces in the torsion spring are held by a simple configuration, so that the biasing force generated between the arm portions can be efficiently It becomes possible to transmit to the cantilever member.

A key switch device according to a fourth aspect is the key switch device according to the third aspect, wherein the first holding portion movably holds the first arm portion, and the second holding portion is the second.
It is characterized in that the arms are fixedly held. In the key switch device according to claim 4, the first holding portion movably holds the first arm portion, the second holding portion fixedly holds the second arm portion, and the second spring portion is generated by the torsion spring. The force is transmitted from the first arm portion that abuts the cantilever member to the cantilever member. At this time, since the first arm portion is movably held by the first holding portion, the key When the top is pressed down, the first arm portion flexibly moves in the first holding portion in response to the reaction force caused by the contact force generated between the first cam portion and the second cam portion, The cam portion and the second cam portion can be constantly brought into contact with each other.

Further, the key switch device according to a fifth aspect is the key switch device according to the fourth aspect, wherein the one cam portion supported by the cantilever member has a first cam portion parallel to the first arm portion. One cam surface is formed, and the other cam portion of the first cam portion and the second cam portion abuts the first cam surface at an abutting portion at an acute angle in plan view and has a sloped surface. A second cam surface is formed, and a gap opened from the contact portion toward the fixed point side of the biasing member is provided between the first cam surface and the slope. Characterize.

According to another aspect of the key switch device of the present invention, the first cam surface is formed on one of the cam portions, and the other cam portion abuts against the first cam surface at an acute angle in a plan view. A second cam surface having an inclined surface is also formed, and a gap opened from the contact portion toward the fixing point side of the biasing member is provided between the first cam surface and the inclined surface. Therefore, when the acute-angled second cam surface is worn by repeatedly performing the switching operation in the switch portion based on the pressing operation of the key top, the second cam surface is located between the first cam surface and the sloped surface. The existing gap wears in the direction in which it gradually closes from the contact portion toward the fixed point side of the biasing member.
As a result, the point of application of the biasing force of the biasing member comes closer to the fixed point side of the biasing member, so that the biasing force exerted on the cantilever member via the biasing member becomes large. As a result, even when the initial biasing force of the biasing member is reduced due to the wear of the second cam surface, the reduction of the initial biasing force is caused at the contact portion between the first cam surface and the second cam surface. As the action point of the biasing force approaches the fixed point side of the biasing member, the increase in the biasing force offsets each other.
Therefore, even when the switching operation is repeated over a long period of time, it is possible to reliably prevent and significantly stabilize the key top pressing characteristics, and ensure a stable switching operation for a long period of time. It becomes possible to do.

A keyboard according to a sixth aspect comprises at least two key switch devices according to the first aspect. Since the keyboard according to the sixth aspect includes the key switch device according to the first aspect, it is possible to obtain the same effect as the case of the first aspect.

Further, an electronic apparatus according to a seventh aspect has a key top and a pair of first and second link members movably arranged below the key top. The first and second link members are provided. A key switch device for performing a switching operation of a switch portion while guiding the vertical movement of a key top via a first cam portion formed on the first link member and the second link member, A second cam portion facing the first cam portion and at least one cam portion of the first cam portion and the second cam portion are supported, and cantilevered from the first link member or the second link member. With the cantilever member that was taken out,
The first cam portion and the second cam portion, the biasing member elastically biasing the cantilever member supported by the one cam portion in a direction in which the first cam portion and the second cam portion contact each other; Division and second
The first cam portion and the second cam portion contact each other at the contact portion with the cam portion, and the first cam portion and the second cam portion act on the contact portion via the biasing member as the switching operation is repeatedly performed. Is equipped with a key switch device having a shape that shifts to a predetermined fixed point side of the biasing member, a keyboard for inputting characters and symbols, a display means for displaying characters and symbols, and a keyboard from the keyboard. It is characterized in that the display means is provided with control means for displaying characters, symbols and the like on the basis of input data.

In the electronic device according to the seventh aspect, when a character, a symbol or the like is input through a key switch device attached to the keyboard, the character, the symbol or the like is controlled by the control means based on the input data from the keyboard. Is displayed on the display means.

At this time, the electronic device according to claim 7 is provided with the keyboard provided with the key switch device according to claim 1, and therefore, as in the case of claim 1, the first cam portion of the first link member is provided. And one cam portion of the second cam portion of the second link member is supported by a cantilever beam member extending in a cantilever shape from the first link member or the second link member, and Since the cantilever member is biased by the biasing member in the direction in which the second cam portion abuts each other,
The key top is urged upward by the contact state between the first cam portion of the link member and the second cam portion of the second link member and the cooperation of the urging member that urges the cantilever member. The key top can be held at the non-pressed position, and the key top can be returned to the non-pressed position when the key is released. Therefore, it is possible to reduce the cost by configuring the key switch device without using a rubber spring or a complicated biasing mechanism.

Further, the first cam portion and the second cam portion are always in contact with each other by urging the cantilever member via the urging member, which corresponds to the vertical movement of the key top. Since the contact position changes, it is possible to freely design the click feeling generated during key operation by changing the shapes of the first cam portion and the second cam portion as needed.

Further, by elastically biasing the cantilever member via the biasing member, one cam portion of the first cam portion or the second cam portion supported by the cantilever member is made to move to the other. Although it is made to contact with the cam portion, the elastic force for contacting the first cam portion and the second cam portion with each other is expressed based on the elastic force of the cantilever member and the elastic force of the biasing member. To be done.

At this time, the switching operation is repeatedly performed by the switch section based on the pressing operation of the key top, so that the abutting section between the first cam section and the second cam section is worn away and the contact is made via the biasing member. Even when the initial biasing force exerted on the cantilever member becomes small, the first cam portion and the second cam portion perform the switching operation repeatedly by the switch portion, and accordingly, the first cam portion via the biasing member. The action point of the urging force acting on the contact portion of the second cam portion and the second cam portion has a shape that shifts toward the predetermined fixed point side of the urging member, and the action point of the urging force is the urging member. Therefore, the urging force exerted on the cantilever member via the urging member becomes large.

Therefore, the decrease in the initial urging force by the urging member caused by the wear in the contact portion between the first cam portion and the second cam portion is caused by the point of action of the urging force in the contact portion. As the biasing members come closer to the fixed point side, the increased biasing forces offset each other. Therefore, even when the switching operation is repeated over a long period of time, it is possible to reliably prevent and significantly stabilize the key top pressing characteristics, and ensure a stable switching operation for a long period of time. It becomes possible to do.

Further, even when the elastic force of the cantilever member is reduced by repeatedly performing the switching operation, as described above, the biasing member urges the contact portion between the first cam portion and the second cam portion. The biasing force exerted on the cantilever member via the biasing member becomes large based on the point of action of the biasing force approaching the fixed point side of the biasing member, so the cantilever member is increased by the increased biasing force. It is possible to compensate for the decrease in the elastic force of the key top, which also makes it possible to stabilize the pressing characteristic of the key top.

[0027]

BEST MODE FOR CARRYING OUT THE INVENTION A key switch device, a keyboard and an electronic device according to the present invention will be described below in detail with reference to the drawings based on a first embodiment embodying the present invention. First, FIG. 1A shows a notebook personal computer which is a kind of electronic device according to the present embodiment.
A description will be given based on (B). FIG. 1 shows a laptop personal computer, FIG. 1A is a perspective view of the laptop personal computer, and FIG. 1B is a block diagram showing an electrical configuration of the laptop personal computer.

In FIG. 1A, a notebook personal computer 100 basically includes a main body 102 having a CPU 101 for performing various arithmetic processes, and a main body 1.
Display 103 supported to be openable and closable with respect to 02
It consists of Here, the display 103 is
It is rotatably supported by the connecting portion 104 of the main body 102 and can be opened and closed with respect to the main body 102. The main body 102 includes a plurality of key switch devices 1
A keyboard 105 in which is provided is provided.

Further, in FIG. 1B, the CPU 101
A ROM 106 in which a program for controlling each unit of the personal computer 100 is stored and a RAM 107 for storing various data are connected to the computer via a bus 108. In addition, the CPU 101 has a bus 108
An input / output interface 109 is connected via the input / output interface 109. The display 103, the keyboard 105, and a hard disk device 110 in which programs such as documents and spreadsheets are stored are connected to the input / output interface 109. The CPU 101 has a keyboard 105
Based on the input data from, the program such as document creation and spreadsheet is read from the hard disk device 110 and executed, and characters and symbols are displayed on the display 103.

Next, the schematic configuration of the key switch device according to the present embodiment, which is attached to the keyboard 105 of the notebook personal computer 100, will be described with reference to FIG. FIG. 2 is an exploded perspective view of the key switch device.

First, referring to FIG. 2, the key switch device 1
Is basically the key top 2 and the pair of first link members 3.
And a second link member 4 for guiding the vertical movement of the key top 2, and a membrane switch sheet 7 disposed on the support plate 6 below the guide member 5.
(See FIG. 5).

Here, the key top 2 is molded from ABS resin or the like, and characters such as letters and numbers are formed on the surface by printing or the like. On the back surface of the key top 2, two rotation locking portions 8 corresponding to the first link member 3 are integrally formed, and two rotation locking portions corresponding to the second link member 4 are rotated. The locking portions 9, 9 are integrally formed. The rotation locking portions 8 and 9 have locking grooves 8 respectively.
A and 9A are provided. Locking groove 8 of each rotation locking portion 8
A locks an upper shaft portion 21 (described later) of the first link member 3 rotatably, and locks grooves 9A of each rotation lock portion 9.
Rotatably locks the upper shaft portion 21 (described later) of the second link member 4. Furthermore, on the back side of the key top 2,
As shown in FIG. 5, a recess 50 is provided. The recess 50 is a portion where the upper ends of the first link member 3 and the second link member 4, which will be described later, come into contact, and the key top 2
The first link member 3 and the second link member 4 are stably positioned corresponding to the non-depressed state. It suffices that they are integrated at the time of assembly, and the rotation locking portions 8 and 8 may be formed separately from the key top 2.

The guide member 5 is formed by combining the first link member 3 and the second link member 4 with each other, and the first link member 3 and the second link member 4 have similar structures to each other. There is. The detailed configurations of the first link member 3 and the second link member 4 will be described later.

Further, below the guide member 5, as shown in FIG. 5, a membrane switch sheet 7 mounted on a support plate 6 made of a thin metal plate made of aluminum, iron or the like is provided. . The membrane switch sheet 7 is composed of a lower film sheet on which a switch circuit pattern including a fixed electrode pattern is formed from a so-called copper foil, a conductive paint or the like, and an upper film sheet on which a movable electrode pattern is similarly formed on the lower surface. It has a three-layer structure in which a film spacer provided with switching holes corresponding to the fixed electrode pattern and the movable electrode pattern is interposed. The structure of such a membrane switch sheet is well known and has the same structure as the structure described in the specification and the drawing of Japanese Patent Application No. 2000-99148, and therefore its detailed description is omitted here.

Here, on the upper switch sheet, two chip-shaped locking members 1 made of metal, resin or the like are provided.
0 is bonded and fixed by an adhesive on both sides of the movable electrode pattern. Each locking member 10 has the same structure,
Long-hole shaped locking grooves 10A are formed on both sides of the central adhesive fixing portion 10B. Further, an adhesive fixing portion 10C is provided outside each locking groove 10A. Each locking member 10 is arranged below the side edge of the key top 2 which is off the center of the key top 2.

In each locking groove 10A, the lower shaft portion 22 of the first link member 3 and the lower shaft portion 22 of the second link member 4 are provided.
Is slidably locked. Here, the wall portion 10D includes the lower shaft portion 22 of the first link member 3 and the lower shaft portion 22 of the second link member 4 when the key top 2 is not pressed, as described later.
Contact with each other, and act to restrict the key top 2 to the non-pressed position.

Further, in each locking member 10, a wall member 31 is integrally formed on the inner side edge near each locking groove 10A. As shown in FIG. 2, each wall member 31 has a curved shaft restricting surface 31A, and the shaft restricting surface 31A of the wall member 31 has a first link member 3 and a second link member 4 which will be described later. Regulating projection 30 formed on the plate-shaped body 18 of
Are always in contact. The locking member 10 and the wall member 31 can be integrally formed with the support plate 6 by punching and pressing the support plate 6 made of a thin metal plate.

The structure for adhering and fixing each locking member 10 to the upper surface of the upper film sheet of the membrane switch sheet 7 is the same as the structure described in the specification and drawings of Japanese Patent Application No. 11-32608. For the detailed description, reference is made to the specification and drawings of Japanese Patent Application No. 11-32608, and the description thereof is omitted here.

Next, detailed structures of the two first link members 3 and the second link members 4 constituting the guide member 5 will be described with reference to FIGS. 2 and 3. Here, the first link member 3 and the second link member 4 have slightly different configurations. FIG. 3 shows the first link member 3 and the second link member 4, FIG. 3 (A) is a plan view thereof, and FIG. 3 (B) is a side view thereof.

2 and 3, the first link member 3
Is a pair of plate-like bodies 18, 18, a first connecting portion 19 for connecting the central portion of each plate-like body 18, and a second connecting portion 20 for connecting between the outer end portions of each plate-like body 18 is a polyacetal. It is configured by being integrally formed from resin or the like. Each plate 1
An upper shaft portion 21 extends outward at a position near one end side (upper end in FIG. 2, right end in FIG. 3) of 8 and the other end of each plate-like body 18. On the side (the lower end in FIG. 2, the left end in FIG. 3), the lower shaft portion 22 extends outward. Each upper shaft portion 21 is rotatably locked in the locking groove 8A of the rotation locking portion 8 of the key top 2 described above,
In addition, each of the lower shaft portions 22 is provided with the membrane switch sheet 7
Is slidably locked in the locking groove 10A of the locking member 10 that is adhesively fixed to the surface of the upper film sheet.

In the second connecting portion 20, a first cam portion 24A is integrally formed at an outer position slightly deviated from the central position thereof. The first cam portion 24A is provided with a cam surface 25A (see FIG. 5) which is formed in an acute angle shape in plan view and has a slope 60. Such cam surface 2
5A and the surface which is continuous with the cam surface 25A, the boundary portion of FIG.
As shown in, the cam apex 27A is present. Here, as is apparent from FIG. 5, the cam surface 25A cooperates with the cam surface 25A of the second link member 4 to hold the key top 2 in the non-depressed position, as will be described later. Also, the first
A cam synchronizing portion 61 is formed adjacent to the cam portion 24A (see FIG. 3). The cam synchronizing part 61 is provided with the pressing part 6.
1A and the recess 61B are integrally formed, and the cam synchronizing portion 6 formed on the cantilever member 32 of the second link member 4 is formed.
Synchronize in cooperation with 2. The synchronization operation will be described later.

In each plate member 18, the upper shaft portion 2
A gear tooth portion 28 is provided on the end portion side (the right end side in FIGS. 2 and 3) with respect to 1. The gear tooth portion 28 is
It has one gear tooth 28A and two gear teeth 28B. Incidentally, in FIG. 3B, one side (FIG.
Two gear teeth 28B are formed in the gear tooth portion 28 of the plate-shaped body 18 on the lower side of (A), and the other side (FIG. 3A).
One gear tooth 28 </ b> A is formed on the gear tooth portion 28 of the plate-shaped body 18 (on the upper side). The gear tooth portions 28 of the first link member 3 and the second link member 4 are in mesh with each other, and when the key top 2 is moved up and down, the first link member 3 is moved.
And the second link member 4 are operated in synchronization with each other.

Further, a resin elastic piece 23 extending from the inner wall of one plate-like body 18 (lower plate-like body 18 in FIG. 3 (A)) to approximately the center of the distance between the plate-like bodies 18 is integrated. The switch pressing portion 26 is provided at the lower end of the resin elastic piece 23. As will be described later, the switch pressing portion 26 of the resin elastic piece 23 elastically presses the movable electrode pattern on the upper switch sheet of the membrane switch sheet 7 from above when the key top 2 is pressed,
The switching operation is performed with the fixed electrode pattern of the lower film sheet.

A restricting projection 30 is formed so as to extend outward from the side surface of each plate-like member 18 of the first link member 3. As described above, the restriction protrusion 30 has
Axial regulating surface 31A of the wall member 31 formed on the locking member 10
Is always in contact with.

Next, the structure of the second link member 4 will be described with reference to FIGS. FIG. 4 is a plan view of the torsion spring. The same members as those of the first link member 3 will be described with the same reference numerals.

In each of these drawings, the second link member 4
Is a pair of plate-like bodies 18, 18, a connecting portion 19 for connecting each plate-like body 18, and one end of one plate-like body 18 (the left end of the lower plate-like body 18 in FIG. 3) It is configured by integrally forming a cantilever member 32 extending in a cantilever shape toward one side from polyacetal resin or the like. An upper shaft portion 21 extends outward at a position near one end side (upper end in FIG. 2, left end in FIG. 3) of each plate-shaped body 18. The other end side of 18 (Fig. 2
At the lower end (the right end in FIG. 3), the lower shaft portion 22 extends outward. Each upper shaft portion 21 is rotatably locked in the locking groove 9A of the rotation locking portion 9 of the key top 2 described above, and each lower shaft portion 22 is an upper film of the membrane switch sheet 7. It is slidably locked in the locking groove 10A of the locking member 10 that is adhesively fixed to the surface of the sheet.

A second cam portion 24B is integrally formed on the outer end of the cantilever member 32. 2nd cam part 2
4B, like the first cam portion 24A, there is a cam surface 25 downwardly.
A is formed, and at the boundary between the cam surface 25A and a surface continuous with the cam surface 25A, the cam apex 27A is formed.
Are formed. Here, as apparent from FIG. 5, the cam surface 25A cooperates with the cam surface 25A of the first link member 3 to hold the key top 2 in the non-pressed position.
The cam surface 25A of the second cam portion 24B is parallel to the first arm portion 33A of the torsion spring 33 described later (see FIG. 6). Here, since the cam surface 25A of the first cam portion 24A is formed in an acute angle shape in plan view and has the slope 60 as described above, the cam surface 25A of the second cam portion 24B is formed. The first cam portion 24A and the first cam portion 24A are not surface contact with each other when the key top 2 is not pressed, but are linear contact portions along the ridge line of the acute-angled protrusion on the cam surface 25A of the first cam portion 24A. They are brought into contact with each other (see FIG. 5 (A) and FIG. 6). As the key top 2 is pushed down, as will be described later, the first cam portion 24A
And, the cam vertices 27A of the second cam portion 24B come into contact with each other at a point-shaped contact portion (see FIGS. 5B and 5C). These contact portions serve as an action point S (see FIG. 6) where the biasing force of the torsion spring 33 acts. In such a configuration, a gap 63 is provided between the cam surface 25A of the second cam portion 24B and the slope 60 of the first cam portion 24A as shown in FIG. 6, and the gap 63 will be described later. Is open toward the fixed point 64 (center point of the coil portion 33C) side of the torsion spring 33. Also,
A cam synchronizing portion 62 is formed adjacent to the second cam portion 24B (see FIG. 3 (B)). The cam synchronization unit 62 is
The pressing portion 62A and the recessed portion 62B are integrally formed, and cooperate with the cam synchronizing portion 61 formed on the first link member 3 to perform a synchronizing action. Specifically, the pressing portion 61A of the cam synchronizing portion 61 of the first link member 3 is placed on the recess 62B of the cam synchronizing portion 62 of the second link member 4, and the pressing portion 62A of the cam synchronizing portion 62 is ,
It is placed in the concave portion 61B of the cam synchronizing portion 61.
Each of the synchronizing portions 61 and 62 configured as described above has the cam surface 2 of the first cam portion 24A when the key top 2 is not pressed.
5A and the cam surface 25A of the second cam portion 24B are brought into contact with each other at a linear contact portion, but when the key top 2 is pushed down, the cam tops of the first cam portion 24A and the second cam portion 24B. Two
The key tops 2A may come into contact with each other at a point-shaped contact portion, and if the cam vertices 27A are displaced from each other in the vertical direction, the key top 2 may be impaired in operation. The cam vertices 27A are synchronized with each other so that the cam vertices 27A are not displaced from each other in the vertical direction during the pressing operation of 2.

In each plate member 18, the upper shaft portion 2
1 to the end side (left end side in FIGS. 2 and 3) than
Gear teeth 28 are provided. The gear tooth portion 28 has one gear tooth 28A and two gear teeth 28B.
Incidentally, in FIG. 3B, one gear tooth 2 is provided in the gear tooth portion 28 of the plate-shaped body 18 on one side (the lower side of FIG. 3A).
8A is formed and the other side (upper side of FIG. 3A)
Two gear teeth 28B are formed on the gear tooth portion 28 of the plate-shaped body 18.

Further, from the side surface of each plate-like body 18 of the second link member 4, a regulating projection 30 is formed so as to extend outward. As described above, the restriction protrusion 30 has
Axial regulating surface 31A of the wall member 31 formed on the locking member 10
Is always in contact with.

Further, a region surrounded by the connecting portion 19, each plate-like member 18 and the cantilever member 32 has a spring arranging portion 34 for arranging the torsion spring 33 shown in FIG.
Make up. As shown in FIG. 4, the torsion spring 33 has a coil portion 33C between the first arm portion 33A and the second arm portion 33B, and the cantilever member 32 is moved toward the left side in FIG. Energize elastically. Then, in the spring arrangement portion 34, the first holding portion 3 having the U-shaped wall portion 35 formed on the inner wall surface of the one plate-shaped body 18.
6, a second holding portion 38 having three fixing pieces 37 formed to face the cantilever member 32 at the connecting portion 19, and
A third holding portion 40 having two fixing pieces 39 formed on the inner surface of the cantilever member 32 so as to face each fixing piece 37,
It is provided.

Here, the wall portion 35 of the first holding portion 36 has the first arm portion 33 of the torsion spring 33 within the U-shaped groove thereof.
Hold the end of A movably. Each fixing piece 37 of the second holding portion 38 fixedly holds the second arm portion 33B. Third
Each fixing piece 39 in the holding portion 40 fixedly holds the first arm portion 33A.

In such a structure, as will be described later, when the key top 2 is pushed, the pushing force based on the pushing is applied to the first cam portion 24A of the first link member 3 and the second cam portion 24A which are in contact with each other. It acts on the second cam portion 24B of the link member 4. At this time, in the first link member 3, the second connecting portion 2
0 does not elastically deform, and the first cam portion 24A remains held at that position, but the cantilever member 32 deforms, so the second cam portion 24B resists the biasing force of the torsion spring 33. Move to the right side in FIG. In this state, the first arm portion 33A of the torsion spring 33
Is held via each fixing piece 39 of the third holding portion 40, and the second arm portion 33B is fixedly held via each fixing piece 37 of the second holding portion 38. Since the end portion of 33A is movable in the U-shaped groove of the wall portion 35 of the first holding portion 36 in response to the deformation of the cantilever member 32, the second cam based on the deformation of the cantilever member 32. The movement of the portion 24B to the right side in FIG. 3 corresponds to the movement of the end portion of the first arm portion 33A in the U-shaped groove of the wall portion 35.
In this way, the torsion spring 33 constantly biases the cantilever member 32 in the direction in which the first cam portion 24A and the second cam portion 24B come into contact with each other. Therefore, the first cam portion 24
The elastic force that brings A and the second cam portion 24B into contact with each other is
Elastic force of cantilever member 32 and torsion spring 33
It is expressed based on the elastic force of. During the pressing operation of the key top 2, the torsion spring 33, as described above,
Although the second cam portion 24B is urged toward the first cam portion 24A, the coil portion 33C of the torsion spring 33 does not move during this period, so that the center point of the coil portion 33C is fixed at a fixed point 64 for convenience. And

Next, the operation of the key switch device 1 according to the first embodiment will be described with reference to FIGS. FIG. 5 shows the key top 2 when the key top 2 is not pressed.
FIG. 6 is an explanatory view schematically showing a series of operations from pressing to perform a switching operation, focusing on the movement of the first link member 3 and the second link member 4, and FIG. It is explanatory drawing which expands the contact state of 1 A cam part 24A and the 2nd cam part 24B by planar view, and is shown typically.

In FIG. 5, first, in the non-depressed state in which the key top 2 is not depressed, the key top 2 is shown in FIG.
As shown in (A), it is held in the non-depressed position. In this state, the cam surface 25A of the first cam portion 24A of the first link member 3 and the second cam portion 2 of the second link member 4
The cam surfaces 25A in 4B are in contact with each other, and in this contact state, the biasing force of the torsion spring 33 acts in a direction in which the cam surfaces 25A contact each other. As a result, as shown in FIG.
The lower shaft portion 22 of the first link member 3 contacts the inner wall surface of the wall portion 10D of the locking groove 10A of the locking member 10, and
Similarly, the lower shaft portion 22 of the second link member 4 is in contact with the inner wall surface of the wall portion 10D of the locking groove 10A in the locking member 10, so that the key top 2 is stably placed in the non-depressed position. Is held. Further, in the contact state in which the cam surfaces 25A are in contact with each other, the biasing force of the torsion spring 33 acts in the direction in which the cam surfaces 25A are in contact with each other, and therefore, the key top held in the non-depressed position. It is possible to prevent the key top 2 from rattling because the 2 does not move in the horizontal direction. At this time, the first
The regulation projection 30 formed on each plate-shaped body 18 of the link member 3 and the second link member 4 is in contact with the upper side of the shaft regulation surface 31A of the wall member 31. Further, in plan view, as shown in FIG. 6, the cam surface 25A of the first cam portion 24A, which is formed in an acute angle shape in plan view and has the slope 60, and the first arm portion 33A of the torsion spring 33. The cam surface 25A of the second cam portion 24B which is made parallel to the key top 2
The cam surface 25 of the first cam portion 24A in the non-pressed state of
They are in contact with each other at a linear contact portion (point of action S) along the ridgeline of the acute-angled projection in A.

When the pressing of the key top 2 is started, the upper shaft portion 21 of the first link member 3 moves in the locking groove 8A of the rotation locking portion 8 in the clockwise direction in FIG. While rotating, the upper shaft portion 21 of the second link member 4 rotates in the locking groove 9A of the rotation locking portion 9 in the counterclockwise direction in FIG. At the same time, the lower shaft portion 22 of the first link member 3 slides in the locking groove 10A of the locking member 10 to the left in FIG. 5, and the lower shaft portion 22 of the second link member 4 locks. It slides in the locking groove 10A of the member 10 in the right direction in FIG. At this time, each regulation protrusion 30
Is guided while abutting along the curved surface of the axis restricting surface 31A of the wall member 31. Therefore, the restriction protrusion 30 and the wall member 3
The horizontal movement of the key top 2 can be regulated based on the cooperative action with the first shaft regulation surface 31A. In addition, the cam surface 25 of the first cam portion 24A of the first link member 3
A and the cam surface 25 of the second cam portion 24B of the second link member 4
The contact form with A is such that the respective cam vertices 27A are in contact with each other at a point-shaped contact portion (point of action S). This state is shown in FIG.

At this time, the cam synchronizing parts 61 and 62 are provided.
Has a function of synchronizing the cam vertices 27A so as not to be vertically displaced from each other when the key top 2 is pressed, so that the respective cam vertices 27A are not vertically displaced at all. Cam portion 24A and second cam portion 24
B can be perfectly synchronized.

When the key top 2 is pushed down further, as shown in FIG.
The state shown in (C) is reached. Then, the switch pressing portion 26 formed on the resin elastic piece 23 of the first link member 3 presses the upper film sheet of the membrane switch sheet 7. As a result, the movable electrode pattern formed on the lower surface of the upper film sheet comes into contact with the fixed electrode pattern of the lower film sheet through the switching holes of the film spacer, and a predetermined switching operation is performed. At this time, the lower shaft portions 22 of the first link member 3 and the second link member 4 contact the wall surface on the side opposite to the wall portion 10D in the locking groove 10A, as shown in FIG. 5 (C). Contacted.

Further, since the resin elastic piece 23 is elastically deformed when the key top 2 is further depressed from the state shown in FIG. 5C, the resin elastic piece 23 absorbs the movement amount of the key top 2. Thus, so-called overtravel of the key top 2 can be realized.

After the switching operation is performed as described above, when the depression of the key top 2 is released, the key top 2
Is reverse to the above-described operation due to the interaction between the first cam portion 24A of the first link member 3 and the second cam portion 24B of the second link member 4 and the cooperation of the biasing force of the torsion spring 33. Then, the operation returns to the non-pressed position shown in FIG.

The operation of the torsion spring 33 during the pressing operation of the key top will be described. First, in the non-pressed position of the key top 2 shown in FIG. The cantilever member 32 is constantly urged in a direction in which the portion 24A and the second cam portion 24B come into contact with each other, and each cam in the first cam portion 24A and the second cam portion 24B is based on the urging force of the torsion spring 33. The surfaces 25A abut each other to hold the key top 2 in the non-depressed position. At this time, the first arm portion 33A of the torsion spring 33 is in contact with the end portion (closed portion) of the U-shaped groove of the wall portion 35.

When the key top 2 is pressed,
The pressing force based on the pressing acts on the first cam portion 24A of the first link member 3 and the second cam portion 24B of the second link member 4, which are in contact with each other. At this time, the second connecting portion 20 does not elastically deform in the first link member 3,
The first cam portion 24A is still held at that position, but the cantilever member 32 is deformed, so the second cam portion 24A is deformed.
B moves to the right side in FIG. 3 against the biasing force of the torsion spring 33. In this state, the first arm portion 33A of the torsion spring 33 is fixedly held via each fixing piece 39 of the third holding portion 40, and the second arm portion 33B.
Are held via the respective fixing pieces 37 of the second holding portion 38, and the end portion of the first arm portion 33A is U of the wall portion 35 of the first holding portion 36 in response to the deformation of the cantilever member 32. Move to the open side of the groove.

When the depression of the key top 2 is released, the first arm portion 33A of the torsion spring 33 moves from the open side of the wall portion 35 to the end portion side of the U-shaped groove due to its elastic force,
Finally, the end of the U-shaped groove is abutted and locked.

Here, the cam surface 25A of the first cam portion 24A
And the cam surface 25A of the second cam portion 24B are the key top 2
When the key top 2 is pushed down, the cam vertices 27A of the first cam portion 24A and the second cam portion 24B come into point contact with each other. Since the key tops 2 come into contact with each other, when the pressing operation of the key top 2 is repeated a large number of times, the first cam portion 24A formed in an acute angle is worn. As the first cam portion 24A wears in this way, the force that presses the first arm portion 33A of the torsion spring 33 weakens corresponding to the amount of wear, and as a reaction force thereof, the torsion spring 33
The initial biasing force exerted on the cantilever beam member 32 via is reduced. Further, by repeating the pressing operation of the key top 2, a creep phenomenon occurs in the cantilever member 32, and its elastic force also decreases.

In order to solve such a problem, in the key switch device 1 according to the present embodiment, the cam surface 25A is formed on the second cam portion 24B, and the second cam portion 24A has the second surface.
A cam surface 25A having an inclined surface 60 is formed at the linear and point contact portions of the cam portion 24B with respect to the linear and dot-shaped contact portions, and the inclined surface 60 is formed, and the cam surface of the second cam portion 24B is formed. Since the gap 63 opened from the contact portion toward the fixed point 64 side of the torsion spring 33 is provided between the 25A and the slope 60, the pressing operation of the key top 2 is repeated to form an acute angle. When the cam surface 25A of the first cam portion 24A formed in a shape is worn, the cam surface 25A has a gap 63 existing between the cam surface 25A of the second cam portion 24B and the slope 60 from the contact portion. The torsion spring 33 wears in the direction of gradually closing toward the fixed point 64 side. As a result,
The action point S of the biasing force of the torsion spring 33 is shown in FIG.
As shown in FIG.
Since it approaches the side, the biasing force exerted on the cantilever member 32 via the torsion spring 33 becomes large. As a result, even when the initial biasing force of the torsion spring 33 is reduced due to the wear of the cam surface 25A of the first cam portion 24A, the reduction of the initial biasing force is caused by the first cam portion 24A and the second cam portion. 24
Since the action point S of the biasing force at the contact portion of each cam surface 25A in B approaches the fixed point 64 side of the torsion spring 33, the increased biasing force offsets each other. Therefore, even if the switching operation is repeated for a long period of time, the key top 2
It is possible to surely prevent the pressing characteristic of the key from largely changing and stabilize it, and it is possible to guarantee a stable switching operation for a long period of time.

Further, even when the elastic force of the cantilever member 32 is reduced by repeatedly pressing the key top 2, the contact between the first cam portion 24A and the second cam portion 24B as described above. In the portion, the action point S of the biasing force by the torsion spring 33 is the torsion spring 3
3, the biasing force exerted on the cantilever member 32 via the torsion spring 33 becomes large due to approaching to the fixed point 64 side of 3. Therefore, the elastic force of the cantilever member 32 is increased by the increased biasing force. It is possible to compensate for the decrease, and this also makes it possible to stabilize the pressing characteristic of the key top 2.

As described in detail above, in the key switch device 1 according to the first embodiment, the second cam portion 24B of the second link member 4 is a cantilevered beam-shaped piece extending from the second link member 4. While being supported by the beam member 32, the first
Since the cantilever member 32 is biased by the torsion spring 33 in the direction in which the first cam portion 24A and the second cam portion 24B of the link member 3 contact each other, the first link member 3 of the first 24 A of cam parts and the 2nd link member 4
By the state of contact with the second cam portion 24B and the cooperation of the torsion spring 33 for urging the cantilever member 32, the key top 2 is urged upward and held in the non-pressed position, and It is possible to return the key top 2 to the non-pressed position when the pressing is released.

Therefore, it is possible to reduce the cost by constructing the key switch device 1 without using a rubber spring or a complicated biasing mechanism. The first cam portion 24A and the second cam portion 24B are always in contact with each other by urging the cantilever beam member 32 via the torsion spring 33, and correspond to the vertical movement of the key top 2. As a result, the contact position changes, so that by changing the shapes of the first cam portion 24A and the second cam portion 24B as necessary, it is possible to freely design the click feeling generated during key operation. .

Further, since the second link member 4 is provided with the spring disposing portion 34 for disposing the torsion spring 33, the torsion spring 33 can be integrally incorporated in the second link member 4, resulting in Moreover, it is possible to make the entire key switch device 1 compact.

Further, the first cam portion 24A and the second cam portion 24
A torsion spring 33 having a first arm portion 33A and a second arm portion 33B is used as a biasing member for contacting B with the first arm portion 33A, and the first arm portion 33A is provided with a wall portion 35 of the first holding portion 36 of the spring arrangement portion 34. The first arm portion 33A that holds the second arm portion 33B via the fixing piece 37 of the second holding portion 38 and exerts mutual biasing force on the torsion spring 33.
With a simple configuration that holds the second arm portion 33B, the biasing force generated between the arm portions 33A and 33B can be efficiently transmitted to the cantilever member 32.

Further, the first arm portion 33A is movably held by the U-shaped groove in the wall portion 35 of the first holding portion 36, and the second arm portion 33B is held by each fixing piece 37 of the second holding portion 38. The biasing force that is fixedly held and that is generated by the torsion spring 33 is transmitted to the cantilever member 32 from the first arm portion 33A that abuts the cantilever member 32. At this time, the first arm portion Since 33A is movably held in the U-shaped groove of the wall portion 35 of the first holding portion 36, the first arm portion 33A has the first cam portion 24A and the second cam portion when the key top 2 is pressed. The first holding portion 36 flexibly moves in response to the reaction force caused by the contact force generated between the first holding portion 36B and the first holding portion 24B.
The cam portion 24A and the second cam portion 24B can be constantly brought into contact with each other.

Further, the regulating projections 30 projecting from the side surfaces of the plate-like members 18 of the first link member 3 and the second link member 4 and the locking grooves 10A of the locking member 10 are formed inwardly. Curved shaft regulating surface 3 integrally formed at the side edge
Since the wall member 31 having 1A is provided, the movement of the key top in the horizontal direction can be restricted based on the cooperative action of the restriction protrusion 30 and the shaft restriction surface 31A of the wall member 31.
Further, for restricting the horizontal movement of the key top 2 during the pressing, there is no need for a guide wall, a positioning member, or the like having a relatively large height. Therefore, by adopting a simple configuration, It is possible to reduce the cost.

The second cam portion 24B has a cam surface 25A.
And the second cam portion 24B is formed on the first cam portion 24A.
Of the cam surface 25A having a slope 60 and abutting the cam surface 25A linearly and in points at an acute angle in a plan view.
5A is formed, and between the cam surface 25A of the second cam portion 24B and the inclined surface 60, a gap 63 opened from the contact portion toward the fixed point 64 side of the torsion spring 33 is provided. Therefore, when the cam surface 25A of the first cam portion 24A formed in an acute angle is worn by repeatedly performing the pressing operation of the key top 2, the cam surface 25A is the cam surface of the second cam portion 24B. The gap 63 existing between 25A and the slope 60 is gradually worn away from the contact portion toward the fixed point 64 side of the torsion spring 33 in the direction of gradually closing. As a result, the point S of application of the biasing force of the torsion spring 33 comes closer to the fixed point 64 side of the torsion spring 33, as shown in FIG. 7, so the cantilever member via the torsion spring 33. The biasing force exerted on 32 becomes large. From this, the cam surface 25A of the first cam portion 24A
Even when the initial urging force of the torsion spring 33 is reduced due to the wear of the first cam portion 25A, the reduction of the initial urging force is caused at the contact portions of the cam surfaces 25A of the first cam portion 24A and the second cam portion 24B. As the action point S of the urging force approaches the fixed point 64 side of the torsion spring 33, the increased urging force offsets each other. Therefore, even when the switching operation is repeated over a long period of time, it is possible to reliably prevent the pressing characteristic of the key top 2 from significantly changing and stabilize it, and to achieve stable switching operation over a long period of time. It becomes possible to guarantee.

Further, even when the elastic force of the cantilever member 32 is lowered by repeatedly pressing the key top 2, the contact between the first cam portion 24A and the second cam portion 24B is performed as described above. In the portion, the action point S of the biasing force by the torsion spring 33 is the torsion spring 3
3, the biasing force exerted on the cantilever member 32 via the torsion spring 33 becomes large due to approaching to the fixed point 64 side of 3. Therefore, the elastic force of the cantilever member 32 is increased by the increased biasing force. It is possible to compensate for the decrease, and this also makes it possible to stabilize the pressing characteristic of the key top 2.

The present invention is not limited to the first embodiment described above, and it goes without saying that various improvements and modifications can be made without departing from the spirit of the present invention. For example, in the above-described first embodiment, the present invention is applied to a notebook personal computer, but it goes without saying that the present invention can be applied to an electronic device equipped with a key switch device such as a typewriter or word processor.

Further, in the above-mentioned embodiment, in order to regulate the horizontal movement of the key top 2 during the pressing, the movement regulating mechanism is provided between the locking member 10 and the link members 3, 4. A movement restricting mechanism may be provided between the key top 2 and each of the link members 3 and 4.

Further, in the above embodiment, the upper shaft portions 21 of the first link member 3 and the second link member 4 are connected to the key top 2.
Rotatably locked on the back surface of the lower shaft portion 22 of the locking member 1
Although the movement restricting mechanism of the present invention is embodied in the key switch device 1 that is impulsively locked in the locking groove 10A of 0, the key switch device in which these locking relationships are in the reverse locking relationship is also realized. Of course, the same can be realized.

Further, according to the present invention, the first link member 3 and the second link member 3
A guide member 5 in which the link member 4 and the link member 4 are axially supported in an X shape.
Can be similarly realized.

[0078]

As described above, in the key switch device according to the first aspect, one of the first cam portion of the first link member and the second cam portion of the second link member is connected to the first link member or the first cam portion. The cantilever member extended in a cantilever shape from the two-link member is supported, and the cantilever member is urged by the urging member in the direction in which the first cam portion and the second cam portion abut each other. Therefore, while maintaining the contact state between the first cam portion of the first link member and the second cam portion of the second link member,
By cooperating with the biasing member that biases the cantilever member, it is possible to bias the key top upward to hold it in the non-pressed position, and to return the key top to the non-pressed position when the key is released. Become. Therefore, it is possible to reduce the cost by configuring the key switch device without using a rubber spring or a complicated biasing mechanism. Further, the first cam portion and the second cam portion are always in contact with each other by urging the cantilever beam member via the urging member, and the first cam portion and the second cam portion are in contact with each other in response to the vertical movement of the key top. Since the position changes, it is possible to freely design the click feeling generated when the key is operated by changing the shapes of the first cam portion and the second cam portion as needed.

Further, by elastically urging the cantilever member via the urging member, one cam portion of the first cam portion or the second cam portion supported by the cantilever member is urged to move to the other. Although it is made to contact with the cam portion, the elastic force for contacting the first cam portion and the second cam portion with each other is expressed based on the elastic force of the cantilever member and the elastic force of the biasing member. To be done. At this time, the switching operation is repeatedly performed by the switch section based on the pressing operation of the key top, so that the contact portion between the first cam section and the second cam section is worn and the cantilever member is urged through the biasing member. Even when the initial urging force exerted on the first cam portion and the second cam portion is repeatedly performed by the switch portion, the first cam portion and the second cam portion are connected to the first cam portion and the second cam portion through the urging member. The point of action of the biasing force acting on the contact portion of the cam portion has a shape that shifts toward the predetermined fixed point side of the biasing member, and the point of action of the biasing force is the fixing point of the biasing member. Since it approaches the side, the biasing force exerted on the cantilever member via the biasing member becomes large. As a result, the decrease in the initial urging force of the urging member caused by the abrasion of the contact portion between the first cam portion and the second cam portion is due to the point of action of the urging force at the contact portion of the urging member. As they approach the fixed point side, they will be offset by the increase in the biasing force. Therefore, even when the switching operation is repeated over a long period of time, it is possible to reliably prevent and significantly stabilize the key top pressing characteristics, and ensure a stable switching operation for a long period of time. It becomes possible to do. Further, even when the elastic force of the cantilever member is reduced by repeatedly performing the switching operation, as described above, the action of the urging force by the urging member is exerted at the contact portion between the first cam portion and the second cam portion. As the point approaches the fixed point side of the biasing member, the biasing force exerted on the cantilever member via the biasing member increases, so the elastic force of the cantilever member is increased by the increased biasing force. It is possible to compensate for the decrease in the key top, and this also makes it possible to stabilize the pressing characteristic of the key top.

Further, in the key switch device according to the second aspect of the invention, since the first link member or the second link member is provided with the arranging portion for arranging the urging member, the urging member is the first link member. Alternatively, it can be integrated into the second link member, and as a result, the entire key switch device can be made compact.

Further, in the key switch device according to the third aspect, the torsion spring having the first arm portion and the second arm portion is used as the urging member, and the first arm portion is interposed by the first holding portion of the arrangement portion. Holds the second arm via the second holding part,
With the simple configuration of holding the first arm portion and the second arm portion that mutually exert the biasing force in the torsion spring, the biasing force generated between the arm portions can be efficiently transmitted to the cantilever member. Become.

Further, in the key switch device according to the fourth aspect, the first holding portion holds the first arm portion movably, and the second holding portion
The second arm portion is fixedly held by the holding portion, and the biasing force generated by the torsion spring is transmitted to the cantilever member from the first arm portion that abuts the cantilever member. Since the first arm portion is movably held by the first holding portion, the first arm portion has a contact force generated between the first cam portion and the second cam portion when the key top is pressed. It is possible to constantly bring the first cam portion and the second cam portion into contact with each other while flexibly moving by the first holding portion in response to the reaction force caused by.

Further, in the key switch device according to the fifth aspect of the present invention, the first cam surface is formed on one of the cam portions, and the other cam portion has an acute angle in plan view at the contact portion with the first cam surface. A second cam surface having an inclined surface is formed, and a gap opened from the contact portion toward the fixing point side of the biasing member is formed between the first cam surface and the inclined surface. Since the second cam surface is provided, when the second cam surface having an acute angle is worn by repeatedly performing the switching operation in the switch portion based on the pressing operation of the key top, the second cam surface becomes the first cam surface and the sloped surface. The gap existing between the parts wears in the direction in which the gap gradually closes from the contact part toward the fixing point side of the biasing member. As a result, the point of application of the biasing force of the biasing member comes closer to the fixed point side of the biasing member, so that the biasing force exerted on the cantilever member via the biasing member becomes large. As a result, even when the initial biasing force of the biasing member is reduced due to the wear of the second cam surface, the reduction of the initial biasing force is caused at the contact portion between the first cam surface and the second cam surface. As the action point of the biasing force approaches the fixed point side of the biasing member, the increase in the biasing force offsets each other. Therefore, even when the switching operation is repeated over a long period of time, it is possible to reliably prevent and significantly stabilize the key top pressing characteristics, and ensure a stable switching operation for a long period of time. It becomes possible to do.

Since the keyboard according to the sixth aspect includes the key switch device according to the first aspect, the same effect as in the case of the first aspect can be obtained.

Further, the electronic apparatus according to claim 7 is provided with the keyboard provided with the key switch device according to claim 1, and therefore, as in the case of claim 1, the first cam portion of the first link member is provided. And one cam portion of the second cam portion of the second link member is supported by a cantilever beam member extending in a cantilever shape from the first link member or the second link member, and Since the cantilever member is biased by the biasing member in the direction in which the second cam portion abuts each other,
The key top is urged upward by the contact state between the first cam portion of the link member and the second cam portion of the second link member and the cooperation of the urging member that urges the cantilever member. The key top can be held at the non-pressed position, and the key top can be returned to the non-pressed position when the key is released. Therefore, it is possible to reduce the cost by configuring the key switch device without using a rubber spring or a complicated biasing mechanism.

Further, the first cam portion and the second cam portion are always in contact with each other by urging the cantilever member through the urging member, which corresponds to the vertical movement of the key top. Since the contact position changes, it is possible to freely design the click feeling generated during key operation by changing the shapes of the first cam portion and the second cam portion as needed.

Further, by elastically biasing the cantilever member via the biasing member, one cam portion of the first cam portion or the second cam portion supported by the cantilever member is made to move to the other. Although it is made to contact with the cam portion, the elastic force for contacting the first cam portion and the second cam portion with each other is expressed based on the elastic force of the cantilever member and the elastic force of the biasing member. To be done. At this time, the switching operation is repeatedly performed by the switch section based on the pressing operation of the key top, so that the contact portion between the first cam section and the second cam section is worn and the cantilever member is urged through the biasing member. Even when the initial urging force exerted on the first cam portion and the second cam portion is repeatedly performed by the switch portion, the first cam portion and the second cam portion are connected to the first cam portion and the second cam portion through the urging member. The point of action of the biasing force acting on the contact portion of the cam portion has a shape that shifts toward the predetermined fixed point side of the biasing member, and the point of action of the biasing force is the fixing point of the biasing member. Since it approaches the side, the biasing force exerted on the cantilever member via the biasing member becomes large.

Therefore, the reduction of the initial biasing force by the biasing member caused by the wear of the contact portion between the first cam portion and the second cam portion is caused by the point of action of the biasing force at the contact portion. As the biasing members come closer to the fixed point side, the increased biasing forces offset each other. Therefore, even when the switching operation is repeated over a long period of time, it is possible to reliably prevent and significantly stabilize the key top pressing characteristics, and ensure a stable switching operation for a long period of time. It becomes possible to do.

Further, even when the elastic force of the cantilever member is reduced by repeatedly performing the switching operation, as described above, the biasing member urges the abutting portion of the first cam portion and the second cam portion. The biasing force exerted on the cantilever member via the biasing member becomes large based on the point of action of the biasing force approaching the fixed point side of the biasing member, so the cantilever member is increased by the increased biasing force. It is possible to compensate for the decrease in the elastic force of the key top, which also makes it possible to stabilize the pressing characteristic of the key top.

[Brief description of drawings]

FIG. 1 illustrates a personal computer, FIG. 1A is a perspective view of a laptop personal computer, and FIG.
FIG. 3 is a block diagram showing an electrical configuration of a notebook personal computer.

FIG. 2 is an exploded perspective view of the key switch device according to the present embodiment.

FIG. 3 is a diagram showing a first link member and a second link member, FIG. 3 (A) is a plan view thereof, and FIG. 3 (B) is a side view thereof.

FIG. 4 is a plan view of a torsion spring.

FIG. 5 is an explanatory diagram schematically showing a series of operations from the non-pressed state of the key top to the switching operation by pressing the key top, focusing on the movement of the first link member and the second link member. .

FIG. 6 is an explanatory view schematically showing an abutting state of the first cam portion and the second cam portion in an unpressed state of the key top in an enlarged manner in a plan view.

FIG. 7 is an explanatory diagram schematically showing a state in which the action point of the biasing force of the torsion spring approaches the fixed point side by repeatedly performing the pressing operation of the key top.

[Explanation of symbols]

1 key switch device 2 key tops 3 First link member 4 Second link member 5 Guide member 6 Support plate 7 Membrane switch sheet 8, 9 Rotation locking part 10 Locking member 10A locking groove 10B, C Adhesive fixing part 10D wall 21 Upper shaft 22 Lower shaft 24A 1st cam part 24B 2nd cam part 32 Cantilever members 33 torsion spring 33A First arm 33B Second arm 34 Spring arrangement part 35 wall 36 1st holding part 37 Fixed piece 38 Second holding unit 39 fixed piece 40 Third holding unit 60 slope 63 gap 64 fixed points S point of action

Claims (7)

[Claims] 1. A key top and a pair of first and second link members that are movably arranged below the key top. Up and down movement of the key top is performed via the first and second link members. In a key switch device for performing a switching operation of a switch part while guiding, a first cam part formed on the first link member and a second cam formed on the second link member and facing the first cam part. A cantilever member that supports at least one of the first cam portion and the second cam portion and that extends in a cantilever shape from the first link member or the second link member; A first cam portion and a second cam portion, and a biasing member that elastically biases the cantilever member supported by the one cam portion in a direction in which the one cam portion and the second cam portion are in contact with each other; The second cam portion abuts each other at the abutment portion, and In the cam portion and the second cam portion, the point of action of the biasing force acting on the contact portion via the biasing member shifts toward the predetermined fixed point side of the biasing member as the switching operation is repeated. A key switch device having a shape. 2. The key switch according to claim 1, wherein the first or second link member on which the cantilever member is formed is provided with an arrangement portion for disposing the biasing member. apparatus. 3. The biasing member comprises a torsion spring having a first arm portion that abuts the cantilever member and a second arm portion that faces the first arm portion, and the placement portion has a first arm portion. The key switch device according to claim 2, further comprising a first holding portion that holds the arm portion and a second holding portion that holds the second arm portion. 4. The key switch device according to claim 3, wherein the first holding portion movably holds the first arm portion, and the second holding portion fixedly holds the second arm portion. . 5. A first cam surface parallel to the first arm portion is formed on the one cam portion supported by the cantilever member, and the first cam portion and the second cam portion are formed. On the other cam part of the
A second cam surface having an inclined surface is formed in the contact portion with the cam surface at an acute angle in plan view, and a second cam surface having an inclined surface is formed. The key switch device according to claim 4, wherein a gap opened toward the fixed point side of the biasing member is provided. 6. A keyboard comprising at least two key switch devices according to claim 1. 7. A key top and a pair of first and second link members movably arranged below the key top, and the vertical movement of the key top is performed via the first and second link members. A key switch device for performing a switching operation of a switch part while guiding, wherein a first cam part formed in the first link member and a second cam part formed in the second link member and facing the first cam part. A second cam portion and at least one of the first cam portion and the second cam portion,
The one cam portion is supported in a direction in which the cantilever member extended in a cantilever shape from the link member or the second link member and the first cam portion and the second cam portion are in contact with each other. And a biasing member for elastically biasing the cantilever member, the first cam portion and the second cam portion abut each other at the abutting portion, and the first cam portion and the second cam portion. Is a key switch device having a shape such that the point of action of the urging force acting on the contact portion via the urging member shifts toward the predetermined fixed point side of the urging member as the switching operation is repeated. And a keyboard for inputting characters and symbols, a display unit for displaying characters and symbols, and a control unit for displaying characters and symbols on the display unit based on input data from the keyboard. An electronic device characterized by.