JP2001125705A - Key switch device and keyboard - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the backlash of both link members caused by the backlash of engaged parts concerning a key switch device having a pair of engaging link members. SOLUTION: A key switch device 10 is provide with a pair of engaging link members 16 in the same shape for guiding and supporting a key top 14 to a vertical moving direction on a base 12. Concerning each of respective link members 16, a supporting shaft 20 at one end of each of arm parts 26 is engaged with the base 12 so as to freely slide, and a supporting shaft 32 at the other end of each of arm parts 26 is turnably engaged with the key top 14. A pair of arm parts 26 of each of link members 16 are integrally provided with first and second teeth 34 and 36 having tooth lengths in the direction almost orthogonal to a turn axial line 32a of the supporting shaft 32. These first and second teeth 34 and 36 are located at positions mutually different in the direction of the turn axial line just by respective tooth widths, located at positions mutually different in the direction of a pitch circumference just by each of tooth thickness and formed so that the turn axial line 32a can be formed so as to specify one pitch circle with the turn axial line 32a as a center.

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 operated by keying, and more particularly to a key switch device suitably used for a keyboard which is an input device of an electronic apparatus. Further, the present invention relates to a keyboard provided with many such key switch devices.

[0002]

2. Description of the Related Art Conventionally, in the field of portable electronic devices such as a notebook personal computer and a notebook word processor, the thickness of a device housing including a keyboard is reduced, that is, the height is reduced, in order to improve the portability of the device. Various techniques for doing so have been proposed. In particular, when reducing the height of a keyboard having a large number of key switch devices to be operated by keying, the key switch device is maintained at a predetermined stroke amount while maintaining the stroke amount of the key switch device in order to secure a certain level of operability. It is required to reduce the total height when the device is not operated (switch off) and when the device is pressed down (switch on).

As a key switch device that can be used for a low-profile keyboard, for example, Japanese Patent Laid-Open No. Hei 9-190735 discloses a base, a key top arranged on the base, and a key top raised and lowered on the base by interlocking with each other. Disclosed is a key switch device including a pair of link members that guide and support in a direction, and a switch mechanism that opens and closes a contact point of an electric circuit in response to a vertical movement of a key top. As a pair of link members, they are combined in a V-shape in side view, mesh with each other at one end thereof, are rotatably supported by the base, and slidably engage with the keytop at the other end. Type, and are combined in an inverted V-shape in side view, mesh with each other at one end in a gear shape, are rotatably supported by the key top, and slidably engage with the base at the other end. Are exemplified. Each link member has a pair of arms extending substantially in parallel to each other, a support shaft rotatably engaged with one of the base and the key top at a tip region of the arm, and a rotation of the support shaft. A plurality of teeth each having teeth in a direction substantially perpendicular to the axis are provided.

In the key top, the link members rotate in opposite directions about the support shaft by engaging the respective teeth with each other, and the other end thereof slides in a substantially horizontal direction along the key top or the base. By moving the base, the base can be translated in a substantially vertical direction while maintaining a predetermined substantially horizontal posture. When the keytop is lowered, the pair of link members are accommodated inside the keytop while being substantially laid down. With such a configuration, it is possible to reduce the total height when the key switch device is not operated and when the key switch device is pressed down while maintaining the key stroke of the key top.

In a conventional key switch device having this type of meshing link member, a plurality of teeth provided at the distal end regions of a pair of arms of each link member are arranged in a direction substantially orthogonal to the rotation axis of each link member. Since it protrudes outward with a dent,
The number and size of these teeth tend to affect the height of the key switch device. Therefore, in order to reduce the overall height of the key switch device as much as possible, conventionally, a pair of arms of each link member is provided with a minimum number (about 1 to 3) of the minimum number that enables the link members to interlock. Teeth are provided (for example, see Japanese Patent Application Laid-Open No. 10-283099).

[0006]

In the above-described key switch device having the conventional mesh type link member, since the number of teeth provided on the link member is reduced to a minimum, the key top is particularly moved up and down (the key top is moved up and down). At the upper limit position and the lower limit position of the keying stroke), the meshing of the teeth of both link members becomes shallow, and the backlash increases, so that the two link members tend to rattle. As a result, the parallel movement of the key top from the upper limit position (start of pressing) to the lower limit position (end of pressing) of the keying stroke becomes unstable, and there is a concern that the keying operation characteristics of the key switch device deteriorate. In particular, when the operator hits a key near the outer edge of the upper surface of the key top, the parallel movement of the key top tends to become unstable. In addition, the rattling of the link members and the rattling of the key top caused by the rattling may cause an increase in noise during the keying operation.

Further, for example, in a key switch device described in Japanese Patent Application Laid-Open No. 9-190735, a key top is formed by forming an opening capable of receiving at least one tooth of both link members meshing with each other. The lower limit position and the upper limit position of the key stroke are reduced. However, in order to secure mechanical strength that can support both link members rotatably or slidably, the base is
A certain thickness is required, and as a result, there is a limit in reducing the overall height of the key switch device.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a key switch device having a pair of meshing link members in which the backlash of the meshing portion causes the backlash of the two link members and the shaking of the key top as much as possible. It is to provide a key switch device which can be reduced. Another object of the present invention is to provide a key switch device having a pair of meshing link members, which has an overall height when the key switch device is not operated and when the key switch device is pressed down without affecting the key stroke and the key operation characteristics of the key top. It is to provide a key switch device capable of reducing as much as possible. It is still another object of the present invention to provide a low-profile keyboard having a large number of such key switch devices and having excellent keying operation characteristics.

[0009]

Means for Solving the Problems In order to achieve the above object, the invention according to claim 1 provides a base, a key top arranged on the base, and a key top on the base by meshing and interlocking with each other. In a key switch device including a pair of link members for guiding and supporting in the elevating direction, each of the pair of link members includes a rotating unit rotatably engaged with one of the base and the key top, and a rotating unit. A plurality of teeth having toothing in a direction substantially perpendicular to the rotation axis of the portion, and the plurality of teeth are located at positions different from each other by each tooth width in the rotation axis direction while defining one pitch circle. At least a first tooth and a second tooth to be formed;
A key switch device is provided, wherein the teeth and the second teeth are configured to simultaneously mesh with the second teeth and the first teeth of the other link member, respectively.

According to a second aspect of the present invention, in the key switch device according to the first aspect, each of the pair of link members has a pair of arms extending substantially parallel to each other and sharing a rotation axis. Provided is a key switch device in which a first tooth and a second tooth are formed on both of the pair of arms. According to a third aspect of the present invention, there is provided the key switch device according to the second aspect, wherein the first teeth and the second teeth are formed in the same arrangement on each of the pair of arms. .

According to a fourth aspect of the present invention, there is provided a key top, a key top disposed on the base, a pair of link members meshing and interlocking with each other to guide and support the key top on the base in the elevating direction. A switch mechanism for opening and closing the contacts of the electric circuit corresponding to the lifting operation of the key switch device, the switch mechanism is supported on the base below the keytop, a sheet-like membrane switch having contacts, An operating member that is disposed on the membrane switch, elastically deforms with the elevating operation of the key top, and presses the membrane switch while the key top descends to close the contact, and the base includes a pair of link members. An engagement support for operatively supporting the link members and operatively engaging the link switch, the engagement support being located above the membrane switch. Protrude to provide a key switch according to claim.

According to a fifth aspect of the present invention, in the key switch device according to the fourth aspect, each of the pair of link members is rotatably engaged with one of the base and the key top. And a key switch device having one or more teeth having toothing in a direction substantially perpendicular to the rotation axis of the rotation portion, and the base having an opening capable of receiving at least one tooth of the link members. I will provide a.

According to a sixth aspect of the present invention, in the key switch device according to the fifth aspect, each of the rotating portions of the pair of link members has a shaft extending along the rotating axis, and the base is engaged. The support portion includes a bearing hole for rotatably supporting the shaft, and provides a key switch device formed adjacent to the opening. According to a seventh aspect of the present invention, in the key switch device according to the fifth or sixth aspect, the membrane switch has a through hole capable of receiving at least one tooth of the pair of link members, and the through hole is formed of a base. A key switch device is provided that is aligned with an opening.

According to an eighth aspect of the present invention, there is provided a key top, a key top disposed on the base, a pair of link members meshing and interlocking with each other to guide and support the key top on the base in the elevating direction. A switch mechanism for opening and closing the contacts of the electric circuit in response to the elevating operation of the key switch device, wherein the base is operatively engaged with each of the pair of link members to operably support the link members. A first base provided with an engaging support portion, and a second base disposed below the first base, wherein the switch mechanism is sandwiched between the first base and the second base and has a contact point. A membrane switch, which is arranged on the membrane switch, is elastically deformed by the ascending and descending operation of the keytop, and is pressed by the membrane switch while the keytop is lowered. And a pair of link members, each of the pair of link members being rotatably engaged with one of the first base and the key top, and substantially orthogonal to a rotation axis of the rotation portion. A key switch device comprising one or more teeth having toothing in the direction, each of the first base and the second base having an opening capable of receiving at least one tooth of the link members. I will provide a.

According to a ninth aspect of the present invention, in the key switch device according to the eighth aspect, the membrane switch comprises:
A key switch device having a through hole capable of receiving at least one tooth of a pair of link members, wherein the through hole is arranged in alignment with each opening of the first base and the second base. According to a tenth aspect of the present invention, there is provided a keyboard configured by arranging a large number of the key switch devices according to any one of the first to ninth aspects.

[0016]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. In the drawings, the same or similar components are denoted by common reference numerals. Referring to the drawings, FIG. 1 is an exploded perspective view of a key switch device 10 according to a first embodiment of the present invention, FIGS. 2 and 3 are enlarged views of link members used in the key switch device 10, and FIGS.
5 is a sectional view of the key switch device 10 when it is not operated and when it is pressed down. The key switch device 10 includes a base 12, a key top 14 having an operation surface 14 a that is movable on the main surface 12 a of the base 12 in the elevating direction and that is keyed by an operator's finger, and a key top 14. The electronic device includes a pair of link members 16 that guide and support the key tops in the upward and downward directions, and a switch mechanism 18 that opens and closes contacts of an electric circuit in response to the upward and downward operations of the key top 14.

The base 12 is a frame-like member having a substantially rectangular center opening 20 which is shielded by the key top 14. On the base 12, two pairs of sliding engagement portions 22 are separated from each other in the front-rear direction (the left-right direction in FIG. 4, the same applies hereinafter) along a pair of opposed inner peripheral surfaces 12b defining the center opening 20. Provided. Each sliding engagement portion 22 is provided on the main surface 1 of the base 12.
A guide groove 22a extending in an L-shape having a wall portion protruding from the inner peripheral surface 12b and the inner peripheral surface 12b is formed inside the wall portion and extends substantially parallel to the main surface 12a. The two sliding engagement portions 22 forming each set arrange the respective guide grooves 22a at corresponding positions along the pair of inner peripheral surfaces 12b of the base 12. Further, the sliding engagement portion 22 on the corresponding side in each set is
Are arranged in the front-rear direction along the inner peripheral surface 12b.

The key top 14 is a dish-shaped member having a substantially rectangular planar shape, and has an inner surface 14 opposite the operation surface 14a.
2b, two sets of pivot portions 24 are formed side by side in the front-rear direction. Each pivot portion 24 is provided on the inner surface 14 of the key top 14.
The bearing hole 24a is formed of a plate-like piece projecting upright from b and penetrating in the plate thickness direction, and a notch 24b extending in a direction substantially perpendicular to the inner surface 14b and communicating with the bearing hole 24a is formed. . Each pair of two pivots 24 is a key top 1
In the center region in the front-rear direction of the inner surface 14b of the fourth member 4, a pair of arm portions 26 of each link member 16 described later are arranged apart from each other by a distance that can be connected, and the respective bearing holes 24a are aligned with each other in the axial direction. Positioned. Further, the pivot 24 on the corresponding side in each set is the inner surface 1 of the key top 14.
4b.

The pair of link members 16 have substantially the same shape as each other, and are connected to each other at one end thereof in a gear shape so as to be combined in an inverted V-shape in side view. Each link member 16
Is provided integrally with a pair of arms 26 extending parallel to each other, and a connecting portion 28 connecting the arms 26 to each other at one end. At the first end of each arm 26 adjacent to the connecting portion 28, a support shaft 30 is coaxially protruded to the opposite side of the connecting portion 28. 2
At the end, the support shafts 32 are coaxially protruded toward the same side as the support shaft 30. Each link member 16 is a first member of each arm 26.
A support shaft 30 provided at one end is slidably fitted into a guide groove 22a of each sliding engagement portion 22 of the base 12 as a sliding portion, and a support shaft 32 provided at a second end of each arm portion 26. Are rotatably fitted into the bearing holes 24a of the respective pivoting portions 24 of the key top 14 as pivot portions, and are disposed between the key top 14 and the base 12. Accordingly, each link member 16 rotates between the key top 14 and the base 12 about a rotation axis 32a (FIG. 2) shared by the support shafts 32 of the pair of arms 26 as described later.

As shown in FIGS. 2 and 3, the pair of arm portions 26 of each link member 16 have their tip surfaces adjacent to the respective support shafts 32 substantially perpendicular to the rotation axis 32a of the support shafts 32. A plurality of teeth 34, 36 having teeth in the directions are integrally provided. The plurality of teeth 34, 36 are connected to the rotation axis 32.
one first tooth 3 capable of defining one pitch circle around a
4 and two second teeth which are arranged at positions different from each other by a tooth width in the rotation axis direction with respect to the first teeth 34 and can define a pitch circle substantially the same as the pitch circle by the first teeth 34. 3
6 is included. The first teeth 34 and the second teeth 36 are arranged at positions different from each other by the respective tooth thicknesses in the pitch circumferential direction. That is, the plurality of teeth 34, 36 are in a state where one first tooth 34 is meshed between two second teeth 36,
It has a shape, dimensions, and arrangement so that it can be smoothly rotated like a gear around a rotation axis 32a of the support shaft 32.

A pair of arms 26 of each link member 16
The first teeth 34 and the second teeth 36 are provided in the same arrangement. That is, the first teeth 34 and the second teeth 36 are respectively disposed inside the arms 26 facing each other in the direction of the rotation axis. Therefore, when the pair of link members 16 are combined by engaging the first teeth 34 and the second teeth 36 with each other, each arm 2 of one of the link members 16
6, the first tooth 34 and the second tooth 36 are connected to the other link member 1.
6, the second teeth 36 and the first teeth 34 of each arm 26 are simultaneously engaged with each other.

Each of the pair of link members 16 slides the support shaft 30 provided at the first end of each arm portion 26 into the guide groove 22a of each sliding engagement portion 22 of the base 12 as described above. And the support shaft 32 provided at the second end of each arm portion 26 is rotatably fitted into the bearing hole 24a of each pivot portion 24 of the key top 14, so that the key top 14 and the base 12 Placed between. At this time, the pair of link members 16 are the first tooth 34 and the second tooth 36 of each arm 26 of one link member 16.
And the second teeth 36 and the first teeth 34 of the respective arm portions 26 of the other link member 16 are meshed with each other, so that they can rotate about the support shaft 32 in conjunction with each other.

Therefore, the key top 14 is configured such that the pair of link members 16 rotate in opposite directions in synchronization with the respective support shafts 32, and the respective support shafts 30 slide in a substantially horizontal direction along the base 12. The operation surface 14a is moved in a direction substantially perpendicular to the base 12 by moving the main surface 12a.
While maintaining a predetermined substantially horizontal posture, which is arranged substantially in parallel with. The upper limit position of the keying stroke of the key top 14 is such that the sliding of the pair of link members 16 in the mutually approaching direction of the respective support shafts 30 is performed by the guide grooves 2 of the respective sliding engagement portions 22 of the base 12.
It is defined when locked by the wall part defining 2a (FIG. 4). As the key top 14 descends from this upper limit position, the respective support shafts 30 of the pair of link members 16 slide in mutually reciprocating directions substantially orthogonal to the direction in which the key top 14 moves up and down. When the key top 14 reaches the lower limit position of the key stroke, the pair of link members 16 are housed on the inner surface 14b side of the key top 14 and received in the opening 20 of the base 12 (FIG. 5).

Here, in the key switch device 10, due to the above-described characteristic structure of the pair of link members 16, both link members 16 are moved in the entire operation range from the upper limit position to the lower limit position of the key stroke of the key top 14. Tooth 3
Extremely stable meshing between 4, 36 can be achieved. The first tooth of each arm 26 of one of the link members 16 is shown in FIG. 6 while both link members 16 are rotating over the entire operation range of the keying stroke of the key top 14. 34 are lower and upper second teeth 36a, 36b of the respective arm portions 26 of the other link member 16 which mesh with each other.
Is always in contact with any one of

More specifically, for example, at the upper limit position of the key stroke, the first teeth 34 of one link member 16 are provided.
Is in contact with the lower second teeth 36a of the other link member 16 and is supported from below, but is disengaged from the upper second teeth 36b of the other link member 16 to cause backlash (FIG. 6). (A)). However, at this time, the lower second teeth 36a of the same one link member 16 are in contact with the first teeth 34 of the other link member 16 and are complementarily supported from above. Tooth 34 and second tooth 3
6a is substantially eliminated.

When the key top 14 is pressed down from the upper limit position of the key stroke, the engagement of the first teeth 34 of each link member 16 with the upper and lower second teeth 36a, 36b of the counterpart link member 16 gradually increases, and The key top 14 reaches the lower limit position of the keystroke stroke after passing through the meshing region of. During this time, the meshing state between the first teeth 34 of each link member 16 and the second teeth 36a, 36b of the mating link member 16 changes stably at the same time while exhibiting the above-described complementary support action. Both link members 16 smoothly rotate in conjunction with each other.

At the lower limit position of the key stroke, the first teeth 34 of one link member 16 contact the upper second teeth 36b of the other link member 16 and are supported from above.
The contact with the lower second teeth 36a of the other link member 16 becomes shallow, and backlash begins to occur (FIG. 6B).
reference). However, at this time, since the upper second teeth 36b of the same one link member 16 are in contact with the first teeth 34 of the other link member 16 and are complementarily supported from below,
The rattling between the intermeshing first and second teeth 34 and 36b is substantially eliminated. In this manner, the pair of link members 16 are stably and reliably engaged with each other in the entire operation range from the upper limit position to the lower limit position of the key stroke of the key top 14, and as a result, the play of the two link members 16 is reduced. The rattling and the rattling of the key top 14 due to the rattling are reduced as much as possible.

Switch mechanism 18 of key switch device 10
Are disposed between a key top 14 and a membrane switch 42, each having a pair of sheet substrates 40 each carrying a contact 38, and a key switch 14. Actuating member 4 acting to close both contacts 38 with the downward movement of
And 4. A spacer 46 is provided between the pair of sheet substrates 40 of the membrane switch 42 to support the sheet substrates 40 at a predetermined interval and hold both contacts 38 in an open state.

Both sheet substrates 4 of the membrane switch 42
0 has the configuration of a well-known flexible printed circuit board, and a contact 38 that can be short-circuited to each other is provided on the surface of the film substrate. The sheet substrates 40 are supported on a support plate 48 under the base 12, and the two contacts 38 are arranged to face each other and the opening 20 of the base 12 is formed.
It is positioned at the approximate center of. The operating member 44 is a dome-shaped member integrally formed from a rubber material,
4 a is arranged in the opening 20 of the base 12 with the posture facing the key top 14 side. The operating member 44 has the dome top 44a spaced above the upper sheet substrate 40 when no load is applied. A columnar pressing portion (not shown) extending toward the sheet substrate 40 is formed on the inner surface of the dome top 44a of the operating member 44.

Contact 3 carried on a pair of sheet substrates 40
8 is a strain which each sheet substrate 40 essentially has,
It is normally held open via the spacer 46 and is positioned below the pressing portion of the operating member 44. Actuating member 44
When an external force in a direction approaching the sheet substrate 40 is applied to the dome top portion 44a of the, the operating member 44 is elastically deformed, and the pressing portion presses the upper sheet substrate 40 from the outer surface, thereby closing the pair of contacts 38.

A flexible sheet member 50 formed of a resin material such as polyethylene terephthalate (PET) is provided between the base 12 and the upper sheet substrate 40. The actuating member 44 is at its dome opening end 44b,
It is fixed to the outer surface of the sheet member 50 with an appropriate adhesive or the like. Alternatively, the sheet member 50 can be formed integrally with the operation member 44 from the same rubber material as the operation member 44.

In the key switch device 10, the key top 1
When no external force is applied to the key top 4, the operating member 44 of the switch mechanism 18 is connected to the key top 14 by the outer surface of the dome top 44a.
Is biased and supported at an upper limit position (FIG. 4) vertically away from the base 12. At this time, the membrane switch 42 is in a state where the pair of contacts 38 is open. When the key top 14 is depressed by the keying operation of the operator, the operating member 44 is deformed while applying an upward elastic biasing force to the key top 14, and immediately before the key top 14 reaches the lower limit position (FIG. 5). The contact 38 is closed by pressing the upper sheet substrate 40 from the outer surface. When the pressing force on the key top 14 is released, the operating member 44 is elastically restored, the key top 14 is returned to the upper limit position, the upper sheet substrate 40 is restored, and the contact 38 is opened.

In the key switch device 10 having the above structure, as described above, the pair of link members 16 are stably and reliably engaged with each other in the entire operation range from the upper limit position to the lower limit position of the key stroke of the key top 14. As a result, the rattling of the link members 16 and the rattling of the key top 14 caused by the link members 16 are reduced as much as possible. As a result, the key top 14 moves stably in parallel from the upper limit position (start of pressing) to the lower limit position (end of pressing) of the keying stroke. In particular, the operator touches the key top near the outer edge of the upper surface of the key top 14. Even in such a case, the keying operation characteristics of the key switch device 10 can be favorably maintained. In addition, the rattling between the link members 16 and the key tops 12 can be reduced, so that noise during the keying operation can be effectively reduced. Therefore, according to the key switch device 10, the two arm portions 2 of each link member 16 do not affect the key-top operation characteristics and the key-press sound.
6, the number and size of the teeth 34 and 36 provided can be minimized. As a result, the overall height of the key switch device 10 when it is not operated and when it is pushed down can be reduced as much as possible.

FIG. 7 shows a keyboard 52 constituted by arranging a large number of the key switch devices 10 described above. In the keyboard 52, the base 12 in each of the key switch devices 10, the two sheet substrates 40 of the membrane switch 42, the support plate 48, and the sheet member 50 to which the operating member 44 is fixed are all keys included in the keyboard 52. The switch device 10 can be formed as a large-sized base 12 ′, a sheet substrate 40 ′, a support plate 48 ′, and a sheet member 50 ′ to which a plurality of operating members 44 are fixed. The configuration of the switch mechanism 18 having the dome-shaped operation member 44 described above is known per se, and the key switch device 10 and the keyboard 52 according to the present invention include switches having various configurations other than the above configuration. A mechanism can be employed.

FIGS. 8 and 9 show a key switch device 60 according to a second embodiment of the present invention in which the total height during non-operation and depression operation is reduced by another method. The key switch device 60 includes a base 62, a key top 64 that is disposed above the base 62 so as to be movable in the elevating direction, and has an operation surface 64 a that is touched by an operator's finger. It comprises a pair of link members 66 for guiding and supporting in the elevating direction, and a switch mechanism 68 for opening and closing the contacts of the electric circuit corresponding to the elevating operation of the key top 64.

In the key switch device 60, the first
The base 12 in the key switch device 10 according to the embodiment is omitted, and instead, the key switch device 10
The member corresponding to the support plate 48 is configured as the base 62 that supports the pair of link members 66. The base 62 is made of, for example, a sheet metal material made of steel, and a pair of engagement support portions 70 projecting upright on the main surface 62 a of the base 62 are formed by punching and bending a part of the base 62. . The base 62 is further formed with an opening 72 which is a stamped mark of the engagement support 70 adjacent to the sides of the engagement support 70 facing each other. Each of the engagement support portions 70 is provided with a pair of bearing holes 70a penetrating in the plate thickness direction. The pair of engagement support portions 70
On the main surface 62a of the base 12, a pair of arm portions 74 of each link member 66 described later are arranged parallel to and separated from each other by a distance that allows connection, and the bearing holes 70a are aligned with each other in the axial direction. Positioned.

The key top 64 is a dish-shaped member having a substantially rectangular planar shape, and has an inner surface 64 opposite to the operation surface 64a.
In FIG. 9B, two sets of sliding engagement portions 76 are provided apart from each other in the front-rear direction (the left-right direction in FIG. 9). Each sliding engagement portion 76 has an L-shape with a wall portion protruding from the inner surface 64b of the key top 64, and a guide groove extending substantially parallel to the inner surface 64b between the wall portion and the inner surface 64b. 76a is formed. The two sliding engagement portions 76 forming each set are arranged apart from each other by a distance capable of connecting a pair of arm portions 74 of each link member 66 described later in front and rear end regions of the inner surface 64b of the key top 64. The guide grooves 76a are positioned so as to face each other. Further, the sliding engagement portions 76 on the corresponding side in each set are aligned on the inner surface 64b of the key top 64 in the front-rear direction.

The switch mechanism 68 of the key switch device 60
Is the key switch device 1 according to the first embodiment described above.
0 has essentially the same configuration as the switch mechanism 18.
Therefore, corresponding components are denoted by the same reference numerals, and description thereof will be omitted. However, in the switch mechanism 68, the membrane switch 42 is fixedly mounted on the main surface 62a of the base 62 below the key top 64,
A pair of through holes 78 are formed in both of the pair of sheet substrates 40 each carrying the contact 38 so as to be aligned with the pair of openings 72 of the base 62. Further, the sheet member 50 fixed on the membrane switch 42 with the dome-shaped operation member 44 fixed thereto has a pair of through holes 80 arranged in alignment with the pair of through holes 78 of both sheet substrates 40. It is formed. Therefore, the pair of engagement support portions 70 provided on the base 62 are connected to the pair of through holes 78 of the sheet substrates 40.
And projecting above the membrane switch 42 and the sheet member 50 through a pair of through holes 80 of the sheet member 50.

The pair of link members 66 of the key switch device 60 have substantially the same shape as each other, and are connected to each other at one end in a gear shape so as to be combined in a V-shape when viewed from the side. Each link member 66 integrally includes a pair of arms 74 extending parallel to each other, and a connecting portion 82 that connects the arms 74 to each other at one end. At the other end of each of the arm portions 74 distant from the connecting portion 82, a support shaft 84 is coaxially protruded toward the opposite side of the connecting portion 82. Each link member 66
The connecting portion 82 of each arm 74 is slidably fitted into a guide groove 76a of each sliding engaging portion 76 of the key top 64 as a sliding portion, and is provided at the other end of each arm 74. The support shaft 84 serves as a rotating portion, and the bearing hole 7 of each engagement support portion 70 of the base 62 is provided.
Oa is rotatably fitted into it, and is disposed between the key top 64 and the base 62.

A pair of arms 74 of each link member 66
A plurality of teeth 86 having teeth on a distal end surface adjacent to each support shaft 84 in a direction substantially orthogonal to the rotation axis of the support shaft 84.
Are provided integrally. The pair of link members 66 are supported by a plurality of teeth 86 of each arm 74 of one link member 66 and a plurality of teeth 86 of each arm 74 of the other link member 66, respectively. It is possible to rotate around 84 in conjunction with each other. Therefore,
The plurality of teeth 86 of each link member 66 are the same as the plurality of teeth 86 provided on the corresponding arm 74 of the link member 66 of the interlocking partner.
It has a shape, dimensions and arrangement so that it can smoothly rotate in the form of a gear when meshed with. In this way, each link member 66 rotates between the key top 64 and the base 62 around the rotation axis shared by the support shafts 84 of the pair of arms 74 as the key top 64 moves up and down. I do.

The key top 64 includes a pair of link members 66.
Are rotated in opposite directions in synchronization with the respective support shafts 84, and the respective connecting portions 82 are
The base 62 slides in a substantially horizontal direction along
In parallel with the main surface 62a while maintaining a predetermined substantially horizontal posture in which the operation surface 64a is disposed substantially parallel to the main surface 62a. The upper limit position of the key stroke of the key top 64 is
The sliding of the connecting portions 82 of the pair of link members 66 in the mutually approaching direction is defined at the time when the wall portions defining the guide grooves 76 a of the sliding engaging portions 76 of the key top 64 are locked. (FIG. 9A). As the key top 64 descends from the upper limit position, each connecting portion 82 of the pair of link members 66 slides in the mutually separating direction substantially perpendicular to the direction in which the key top 64 is raised and lowered. When the key top 64 reaches the lower limit position of the key stroke, the pair of link members 66 are housed on the inner surface 64b side of the key top 64 (FIG. 9B).

In the key switch device 60, a pair of openings 72 of the base 62, a pair of through holes 78 of the membrane switch 42, and a pair of through holes 80 of the sheet member 50 are formed.
Each is formed with a size and a shape capable of smoothly receiving at least one tooth 86 of the link member 66. For example, when the key top 64 is at the upper limit position of the key stroke, as shown in FIG.
Some of the plurality of meshing teeth 86 of each of the six
4, the teeth 86 extending downward therefrom form a pair of through holes 80 of the sheet member 50, a pair of through holes 78 of the membrane switch 42, and the base 6.
The two pairs of openings 72 are smoothly received. Therefore, the bearing hole 70 supporting the support shaft 84 of each link member 66 is provided.
a can be arranged as low as possible, and as a result, the height of each engagement support portion 70 provided on the base 62 can be made as low as possible.

In the key switch device 60 having the above-described configuration, the base disposed between the key top 64 and the membrane switch 42 is eliminated, and the support plate conventionally disposed below the membrane switch 42 is used as the base 62. Since they are used together, the overall height of the key switch device 60 is effectively reduced while ensuring the mechanical strength capable of supporting the pair of link members 66 in a rotatable or slidable manner. Moreover, as described above, the through-holes 80 and 78 and the opening 72 that can receive some of the plurality of teeth 86 that mesh with each other of the pair of link members 66 are formed with the sheet members 50 located below the link members 66. Since they are provided on the membrane switch 42 and the base 62, the engagement support portions 70 of the base 62 can be made as low as possible. Therefore, according to the key switch device 60, the total height when the key switch device 60 is not operated and when the key switch device 60 is depressed can be reduced as much as possible without affecting the key stroke and key operation characteristics of the key top 64.

In the above configuration, means for enabling the support shaft 84 provided on the arm portion 74 of each link member 66 to be easily attached to the bearing hole 70a provided on each engagement support portion 70 of the base 62. It is desirable to add For example, as shown in FIG. 10A, a flat surface 84a extending in the axial direction is formed on the cylindrical outer surface of the support shaft 84 to form a support shaft 84 having a D-shaped cross section. 70a
Can be formed to communicate with the notch 70b. In this configuration, the flat surface 84a of the support shaft 84 is set
By passing through Ob, mutual interference is avoided, and the support shaft 84 can be easily inserted into the bearing hole 70a. Or Figure 1
As shown in FIG. 0 (b), a tapered surface 84b may be provided on the cylindrical outer surface of the support shaft 84. In this configuration, the support shaft 8
By interfering the tapered surface 84b of No. 4 with the engagement support portion 70, the bending of the arm portion 74 of the link member 66 is promoted,
As a result, the support shaft 84 can be easily inserted into the bearing hole 70a.

The configuration in which the support plate is used as a base and the base is provided with an engagement support portion operatively engaged with each link member to operably support the link members is described in the above embodiment. The present invention is not limited to the embodiment, and can be applied to the configuration of the link member as in the key switch device 10 of FIG. 1, for example. In this case, the engagement support portion of the base is a sliding portion of the link member (for example, the link member 16 in FIG. 1).
Is formed as a sliding engagement portion that slidably supports the support shaft 30). Further, the membrane switch 42 and the sheet member 50 in the above-described key switch device 60 have a pair of link members 66 instead of having the through holes 78 and 80.
May have an outer shape that does not contact the plurality of teeth 86 meshing with each other. Further, it goes without saying that a keyboard including a large number of the above-described key switch devices 60 can be configured similarly to the keyboard 52 shown in FIG.

FIG. 11 shows a key switch device 90 according to a third embodiment of the present invention, in which the total height during non-operation and depression operation is reduced. The key switch device 90 has essentially the same configuration as the key switch device 60 according to the above-described second embodiment except for the configuration of the base. Therefore, corresponding components are denoted by the same reference numerals, and description thereof will be omitted.

The base of the key switch device 90 includes a first base 94 having an engagement support portion 92 which operatively engages with each of the pair of link members 66 and operably supports the link members 66; And a second base 96 disposed below the first base 94. A switch mechanism 68 is provided between the first base 94 and the second base 96.
Are sandwiched between the membrane switch 42 and the sheet member 50 to which the operating member 44 is fixed.

The first base 94 is a member corresponding to the base 12 in the key switch device 10 described above, and has a substantially circular center opening 9 shielded by the key top 64.
8 and a pair of engagement support portions 92 each formed of a rectangular opening formed on both sides of the center opening 98. On the inner wall of each engagement support portion 92, two bearing holes 92a are provided apart from each other and aligned in the front-rear direction. Each engagement support portion 92
The plurality of teeth 8 of the pair of link members 66 mesh with each other.
It has a size and shape capable of smoothly receiving the distal end region of the arm portion 74 including the shaft 6 and the support shaft 84. In addition, each engagement support portion 92
The support shafts 84 of the pair of link members 66 in a meshing state are rotatably fitted into the two bearing holes 92a. Further, the central opening 98 receives the dome shaped actuating member 44.

The second base 96 is a member corresponding to the support plate 48 of the key switch device 10 described above, and is similarly positioned at a position corresponding to the pair of engagement support portions 92 of the first base 94. Opening 100 is formed.
Each opening 100 is provided with a pair of link members 6 in a meshed state.
It has a size and shape capable of receiving at least one of the six teeth 86. The pair of through holes 78 formed in the pair of sheet substrates 40 of the membrane switch 42 and the pair of through holes 80 formed in the sheet member 50 are formed by a pair of engagement support portions 92 of the first base 94 and a second base 96. A pair of openings 1
00 are arranged in alignment with each other.

In the key switch device 90 having the above configuration, the first base 94 disposed between the key top 64 and the membrane switch 42 has the engagement support portion 92 for supporting the link member 66 through the opening. The through-holes 80, 78 and the opening 100 which can receive some of the plurality of teeth 86 of the pair of link members 66 that are engaged with each other are formed as the sheet member 50 located below the first base 94, and the membrane. Switch 42 and second base 96
Therefore, the overall height of the key switch device 90 is effectively reduced while securing the mechanical strength capable of supporting the pair of link members 66 rotatably or slidably. Therefore, according to the key switch device 90, the key stroke of the key top 64 and the key operation characteristics are not affected.
The total height when the key switch device 90 is not operated and when the key switch device 90 is pressed down can be reduced as much as possible.

[0051]

As is apparent from the above description, according to the present invention, in a key switch device having a pair of interlocking link members, the backlash of the interlocking portions causes the backlash of both link members and causes the backlash. It is possible to reduce the rattling of the key top as much as possible, thereby reducing the noise at the time of the keying operation and improving the keying operability. Further, according to the present invention, the total height of the key switch device when it is not operated and when it is pressed down can be reduced as much as possible without affecting the keying stroke and keying operation characteristics of the key top. A keyboard incorporating a large number of such key switch devices has extremely excellent keying operation characteristics.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of a key switch device according to a first embodiment of the present invention.

FIG. 2 is an enlarged perspective view of a link member used in the key switch device of FIG.

3A and 3B are an enlarged left side view and an enlarged right side view of a link member used in the key switch device of FIG. 1;

FIG. 4 is a cross-sectional view of the key switch device of FIG. 1 taken along line IV-IV when the key switch device is assembled, showing a state where a key top is at an upper limit position of a key stroke.

5 is a sectional view of the key switch device corresponding to FIG. 4,
This shows a state in which the key top is at the lower limit position of the key stroke.

6 is an enlarged view showing a meshing state of a pair of link members in the key switch device of FIG. 1, wherein (a) a key top is at an upper limit position of a key stroke and (b) a lower limit of a key stroke. Indicates when it is in position.

FIG. 7 is a partially cutaway perspective view of a keyboard according to an embodiment of the present invention.

FIG. 8 is an exploded perspective view of a key switch device according to a second embodiment of the present invention.

9 is a sectional view taken along line IX-IX when the key switch device of FIG. 8 is assembled, wherein (a) the key top is at the upper limit position of the key stroke, and (b) the key top is the key stroke. This shows the state at the lower limit position.

10 is an enlarged view of an engagement portion between a link member and a base in the key switch device of FIG. 8, (a) an enlarged perspective view of a support shaft and an engagement support portion according to a modified example, and (b) another perspective view. It is an expansion perspective view of a spindle and an engagement support part by a modification.

FIG. 11 is an exploded perspective view of a key switch device according to a third embodiment of the present invention.

[Explanation of symbols]

 10, 60, 90 ... key switch device 12, 62 ... base 14, 64 ... key top 16, 66 ... link member 18, 68 ... switch mechanism 30, 32, 84 ... support shaft 34 ... first tooth 36 ... second tooth 42 membrane switch 44 operating member 48 support plate 50 sheet member 52 keyboard 70, 92 engagement support 72, 100 opening 78, 80 through hole 86 tooth

Claims (10)

[Claims] 1. A key switch device comprising: a base; a key top disposed on the base; and a pair of link members that mesh with each other and guide and support the key top on the base in a vertical direction. Each of the pair of link members has a rotating portion rotatably engaged with one of the base and the key top, and has a toothing in a direction substantially orthogonal to a rotating axis of the rotating portion. A plurality of teeth having at least a first tooth and a second tooth formed at positions different from each other by a respective tooth width in the rotation axis direction while defining one pitch circle, A key switch device, wherein the first teeth and the second teeth of one of the link members are simultaneously meshed with the second teeth and the first teeth of the other link member, respectively. . 2. Each of the pair of link members has a pair of arms extending substantially parallel to each other and sharing the rotation axis, and the first tooth and the second tooth are both of the pair of arms. The key switch device according to claim 1, wherein 3. The key switch device according to claim 2, wherein the first teeth and the second teeth are formed in the same arrangement on each of the pair of arms. 4. A base, a key top arranged on the base, a pair of link members meshing and interlocking with each other to guide and support the key top on the base in an elevating direction, and a raising / lowering operation of the key top. A key switch device comprising: a switch mechanism that opens and closes contacts of an electric circuit corresponding to the key switch device, wherein the switch mechanism is supported on the base below the keytop and has a sheet-like membrane switch having the contacts. An operating member disposed on the membrane switch, elastically deforming with the ascending and descending operation of the key top, and pressing the membrane switch while the key top descends to close the contact, An engaging support portion operatively engaged with each of the pair of link members and operably supporting the link members, the engaging support portion comprising: Protrude above the serial membrane switch, key switch according to claim. 5. Each of the pair of link members has a rotating portion rotatably engaged with one of the base and the key top, and a direction substantially orthogonal to a rotating axis of the rotating portion. 5. The key switch device according to claim 4, further comprising one or more teeth having a flank, wherein the base has an opening capable of receiving at least one of the teeth of the link members. 6. The rotating portion of each of the pair of link members includes a shaft extending along the rotating axis, and the engagement support portion of the base rotatably supports the shaft. 6. A bearing hole is formed adjacent to the opening.
A key switch device according to item 1. 7. The membrane switch having a through hole capable of receiving at least one of the teeth of the pair of link members, wherein the through hole is aligned with the opening of the base. 7. The key switch device according to 5 or 6. 8. A base, a key top arranged on the base, a pair of link members meshing and interlocking with each other to guide and support the key top on the base in an elevating direction, and an elevating operation of the key top. A key switch device comprising: a switch mechanism for opening and closing the contacts of an electric circuit corresponding to the above, wherein the base is operatively engaged with each of the pair of link members to operably support the link members. A first base having an engagement support portion, and a second base disposed below the first base, wherein the switch mechanism is sandwiched between the first base and the second base; A sheet-like membrane switch having contacts, disposed on the membrane switch,
An actuating member that elastically deforms with the elevating operation of the key top and presses the membrane switch to close the contact while the key top descends, wherein each of the pair of link members is A rotating portion rotatably engaged with one of the base and the key top, and one or more teeth having toothing in a direction substantially orthogonal to a rotating axis of the rotating portion; Each of the first base and the second base has at least one of the link members.
A key switch device having an opening capable of receiving two of said teeth. 9. The membrane switch has a through hole capable of receiving at least one of the teeth of the pair of link members, the through hole being the opening of each of the first base and the second base. 9. The key switch device according to claim 8, wherein the key switch device is arranged in alignment with the key switch. 10. A keyboard configured by arranging a large number of key switch devices according to any one of claims 1 to 9.