JP5094784B2 - Key switch device and keyboard - Google Patents

Description

  The present invention relates to a key switch device that is operated by a keystroke, and more particularly to a key switch device that is preferably used in a keyboard that is an input device of an electronic device. Furthermore, the present invention relates to a keyboard provided with a large number of such key switch devices.

  2. Description of the Related Art Conventionally, in the field of portable electronic devices such as notebook personal computers and notebook word processors, various devices for reducing the thickness of a device housing including a keyboard, that is, reducing the height of the device housing in order to improve portability of the device. Technology has been proposed. In particular, when lowering the height of a keyboard having a large number of key switch devices operated by keystrokes, the key switch is maintained while maintaining the stroke amount of the key switch device at a predetermined amount in order to ensure a certain level of operability. It is required to reduce the overall 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, Patent Document 1 discloses a pair of a base, a key top arranged on the base, and a pair of guide tops that support the key top in the up-and-down direction in mesh with each other. Disclosed is a key switch device including a link member and a switch mechanism that opens and closes a contact of an electric circuit in response to a lifting operation of the key top. The pair of link members are combined in an inverted V shape when viewed from the side, slidably engage with the base in the first end region, and mesh with each other in the second end region and rotate to the key top. It is connected freely. Each link member has a pair of arm portions extending substantially in parallel with each other, and a support shaft that rotatably engages with the key top extends in a terminal region of the arm portions, that is, a second end region. One or more teeth protrude in a direction substantially orthogonal to the support shaft. On the other hand, the key top is provided with four pivoting portions that rotatably support the support shafts of the arm portions of the link members.

  The key top engages with the teeth of the link members and rotates in opposite directions around the support shaft, and the first end region slides along the base to move against the base. It is possible to translate while maintaining a predetermined posture in a substantially vertical direction. When the key top reaches the lower limit position of the lifting / lowering stroke, the pair of link members are accommodated inside the key top in a substantially laid state. 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 not pressed, while maintaining the keystroke stroke amount of the key top.

  The switch mechanism is disposed below the base, and is disposed between a sheet-like switch (referred to herein as a membrane switch) having a pair of sheet substrates carrying a pair of contacts, and between the key top and the membrane switch. And an actuating member that acts to close the pair of contacts in accordance with the downward movement of the key top. The actuating member is a dome-shaped member integrally formed from a rubber material, and is disposed on the membrane switch with the dome top portion facing the key top side through an opening formed in the base at a position below the key top. The A spacer is disposed between the pair of sheet substrates of the membrane switch, whereby the pair of contacts are normally held in an open state and positioned below the protrusion provided on the inner surface of the dome top of the actuating member.

  When an external force is not applied to the key top, the actuating member biases and supports the key top at the stroke upper limit position (initial position) that is vertically upward from the base on the outer surface of the dome top. On the other hand, when the key top is pushed down by the operator's keystroke operation, the actuating member is deformed while exerting an upward elastic biasing force on the key top, and as the key top approaches the stroke lower limit position, the protrusion is moved upward by the protrusion. The sheet substrate is pressed from the outer surface to close the contact. When the pressing force to the key top is released, the operating member is elastically restored to return the key top to the initial position, and the upper sheet substrate is restored to open the contact.

JP-A-11-003628

  In the above-described conventional key switch device, each of the plurality of pivot portions provided on the key top includes a bearing hole that rotatably supports the support shaft of each arm portion of each link member, and a cutout that communicates with the bearing hole. As a plate-like member having a notch, it projects from the inner surface of the key top. The notches in the pivot portions have a width smaller than the thickness of the support shaft of each link member, and extend substantially parallel to each other in a direction substantially perpendicular to the inner surface of the key top. When assembling the key switch device, a pair of link members are combined and placed at a predetermined position on the base (that is, a state corresponding to the stroke lower limit position of the key top). The corresponding link member is pressed onto the support shaft from above, and the support shaft is first press-fitted into the notch of the pivoting portion to elastically deform the pivoting portion, and is snapped into the bearing hole. With this configuration, the key switch device can be easily assembled and the structure of the key top mold can be simplified.

  However, in this configuration, when the mold is detached from the molded key top, the mold part for forming the bearing hole of each pivoting part is forcibly pulled out from each molded pivoting part through the notch. Therefore, as in the case of assembling the link member, each pivoting portion is elastically deformed, and the predetermined shape and size of the bearing hole may be slightly changed after the mold is detached due to the influence. When such a deformation occurs in the bearing hole of each pivoting portion, the key top tends to cause undesirable rattling during the keystroke operation due to an unnecessary gap between the bearing hole and the support shaft of each link member. is there. The backlash of the key top affects the parallel movement of the key top by the guidance of the link member, and as a result, it is feared that it is difficult to accurately close the contacts of the membrane switch. In order to solve such a problem, if the mold part for forming the bearing hole of each pivoting part is configured to be removable in the axial direction, the structure of the mold becomes complicated, and there is a risk that the manufacturing cost will increase. .

  Further, each pivoting portion of the key top is located outside the pair of arm portions of each link member, and pivotally supports a support shaft extending outward from the second end region of each arm portion. That is, a pair of arm parts of a corresponding link member are arranged between a pair of pivot parts. Therefore, when the pair of arm portions of each link member is bent in a direction approaching each other due to a molding error or the like, each pivoting portion of the key top cannot correct this bending, and as a result, each link member It may be difficult to accurately fit the support shafts into the bearing holes of the respective pivot portions. Further, as described above, when the key top is assembled to the link member, the pair of arm portions tend to bend in a direction in which the pair of arm portions approach each other due to a force applied to each support shaft from each pivot attachment portion. It is difficult to accurately insert the support shaft into the bearing hole of each pivot portion. In addition, when the key top receives an external force in the direction of lifting the edge, the pair of arms tend to bend in the direction of approaching each other. In this case, the support shaft of the link member There is a risk that it will be relatively easy to disengage from the key top pivot.

  In order to prevent the support shaft of the link member from easily detaching from the bearing hole of the pivot portion of the key top, it is conceivable that the notch of the pivot portion is further narrowed. However, with this configuration, there is a concern that the force required for assembling the key top to the link member increases and the assembling workability deteriorates. Therefore, it is desired to prevent easy detachment of the link member from the key top without deteriorating the workability of assembling the key top to the link member.

  By the way, in the conventional key switch device, one in which the first end region of the pair of arm portions of each link member slides along a pair of guide grooves formed between the base and the membrane switch is known. ing. In this case, the first end region of each link member slides while receiving frictional resistance in contact with both the base and the membrane switch. In this configuration, when the connecting portion that connects the pair of arm portions of each link member has an outer surface on a surface that is substantially the same as the sliding surface of the first end region of each arm portion, During the lifting and lowering operation of the switch, the connecting part of each link member also contacts the upper surface of the membrane switch and slides while receiving frictional resistance, which may hinder smooth and accurate keying operation of the key top. There is. In particular, in the current configuration in which the base, the link member, and the membrane switch are formed of different materials, the problem of deterioration in operability due to such frictional resistance becomes apparent.

  Further, in a conventional key switch device, generally, a support structure such as a metal support plate or a keyboard lower resin case is provided below the membrane switch. The support structure is usually configured to receive an elastic force applied to the membrane switch from the key top via the dome-shaped operating member and to receive a pressing force when the dome-shaped operating member closes the contact of the membrane switch. Therefore, if dust is present between the support structure and the membrane switch, particularly in the vicinity of the contact, it may be difficult to open and close the contact accurately and stably by a key-top operation. In order to solve such a problem, it is conceivable to assemble the key switch or the keyboard in a clean room, but this is not preferable because it increases the manufacturing cost.

The purpose of the present invention is a key switch having a keytop to be key-entry operation is to provide a key switch which can be assembled a pair of link members to the key top accurately and relatively easily.
Another object of the present invention is to provide a key switch device that can effectively prevent inadvertent detachment of a key top from a pair of link members in a key switch device having a key top that is operated to make a keystroke. .

Still another object of the present invention is to provide a keyboard having a large number of key switch devices as described above and excellent in assembling workability and operability.

The present invention includes a base, a key top disposed on the base, and each of them interlocking with each other and operatively engaging both the base and the key top to guide and support the key top on the base in the up-and-down direction. In a key switch device including a pair of link members and a switch mechanism that opens and closes a contact of an electric circuit in response to the lifting operation of the key top, each of the pair of link members is slidably engaged with a base. A first end region and a second end region that is pivotably engaged with the key top, and a support shaft extends along the rotation axis in the second end region, and the axial direction of the support shaft A slit that extends in a direction intersecting the rotation axis and has a depth from the axial end surface in the direction of the rotation axis is formed on the end surface , and a pair of half-body portions that are divided by the slit are formed on the support shaft. It is, the key top And a plurality of pivot portions having bearing holes for rotatably supporting the respective support shafts of the pair of link members, each of the pivot portions extending substantially parallel to each other and communicating with the respective bearing holes. When the notch is provided and the key top is at the lower limit position of the lifting / lowering stroke, the slit formed in each support shaft of the link member is substantially parallel to the notch provided in each of the pivotal portions of the key top. are arranged in the movement, the pivot portion with a pair of halves are elastically deformed towards each other are configured so as to pass through the-out shaft notch elastically deformed, upward the key top from the lower limit position A key switch device characterized in that the slit is arranged to be inclined with respect to the notch, and the pair of half-body portions are configured not to be deformed to pass through the notch. provide.

The present invention also provides a keyboard configured by arranging a large number of the key switch devices described above .

According to the present invention, the key switch having the key tops to be key-entry operation, it is possible to assemble the pair of link members accurately and relatively easily to key Toppu. Furthermore, inadvertent detachment of the key top from the pair of link members can be effectively prevented.

According to the present invention, a keyboard with excellent set upright workability and operability is provided.

It is a disassembled perspective view of the key switch apparatus by the related technique ( 1st Embodiment ) of this invention. It is a bottom view of the key top used with the key switch apparatus of FIG. It is a top view at the time of the assembly of the base and a pair of link member which are used with the key switch apparatus of FIG. It is a partial notch top view at the time of the assembly of the key switch apparatus of FIG. FIG. 5 is a cross-sectional view taken along line VV of the key switch device of FIG. 4. FIG. 6 is a cross-sectional view of the key switch device of FIG. 4 taken along line VI-VI. It is a disassembled perspective view of the key switch apparatus by embodiment ( 2nd Embodiment ) of this invention. It is an expanded sectional view of the principal part of the key switch apparatus of FIG. 7, and shows the state which has a key top in a stroke lower limit position. It is an expanded sectional view of the principal part of the key switch apparatus of FIG. 7, and shows the state which has a key top in a stroke upper limit position. It is a disassembled perspective view of the key switch apparatus by the related technique ( 3rd Embodiment ) of this invention. It is an expansion perspective view of the link member used with the key switch apparatus of FIG. It is an expansion perspective view of the link member by a modification. It is an expansion perspective view of the link member by other modifications. It is a disassembled perspective view of the principal part of the key switch apparatus by another modification. It is sectional drawing of the key switch apparatus by the related technique ( 4th Embodiment ) of this invention. 1 is a partially cutaway perspective view of a keyboard according to an embodiment of the present invention.

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 shows an exploded perspective view of a key switch device 10 according to a related technique ( first embodiment ) of the present invention. The key switch device 10 includes a base 12, a key top 14 having an operation surface 14 a that is arranged on the main surface 12 a of the base 12 so as to be movable in the up-and-down direction and can be pressed with the fingers of an operator, and the key top 14 as the base 12. A pair of link members 16 that are guided and supported in the up and down direction and a switch mechanism 18 that opens and closes the contacts of the electric circuit corresponding to the up and down movement of the key top 14 are configured.

  The base 12 is a frame-like member having a substantially rectangular central opening 20 that is shielded by the key top 14. The base 12 is provided with two sets of sliding engagement portions 22 spaced apart from each other in the left-right direction along a pair of opposed inner peripheral surfaces 12 b that define the central opening 20. Each sliding engagement portion 22 has a wall portion protruding from the main surface 12a and the inner peripheral surface 12b of the base 12 and extends in an L shape, and extends substantially parallel to the main surface 12a inside the wall portion. A guide groove 22a is formed. The two sliding engagement portions 22 constituting each set have their guide grooves 22 a arranged at corresponding positions along the pair of inner peripheral surfaces 12 b of the base 12. Further, the sliding engagement portions 22 on the corresponding side in each set are aligned in the left-right direction along the inner peripheral surface 12 b of the base 12. Each of the pair of link members 16 is slidably engaged with each sliding engagement portion 22 in a first end region described later.

  The key top 14 is a dish-like member having a substantially rectangular planar shape, and two sets of pivoting portions 24 are juxtaposed with each other on the inner surface 14b opposite to the operation surface 14a. Each pivoting portion 24 is composed of a pair of plate-like bearing members 26 and 28 projecting upright from the inner surface 14 b of the key top 14. As clearly shown in FIG. 2, the two pivoting portions 24 constituting each set are in the center region in the left-right direction of the inner surface 14 b of the key top 14, and are associated with a second end region (described later) of each of the pair of link members 16. The second end regions of the link members 16 are rotatably supported by being separated from each other by a distance that can be combined. Further, the pivoting portions 24 on the corresponding side in each set are aligned in the left-right direction on the inner surface 14 b of the key top 14. The configuration of each pivot portion 24 of the key top 14 will be described in further detail below.

  The pair of link members 16 have substantially the same shape and dimensions as each other, and are connected to each other in a gear shape at one end thereof and are combined in a reverse V shape in a side view. Each link member 16 integrally includes a pair of arm portions 30 and 32 extending in parallel with each other and a connecting portion 34 that connects the arm portions 30 and 32 to each other. In the illustrated embodiment, the proximal end regions of both arm portions 30 and 32 adjacent to the connecting portion 34 constitute the first end region of the link member 16, and the distal end regions of both arm portions 30 and 32 away from the connecting portion 34. Constitutes the second end region of the link member 16. As clearly shown in FIG. 3, in the first end region of each link member 16, a pair of support shafts 36 are coaxially formed from the outer surfaces of the arms 30 and 32 that are separated from each other to the opposite side of the connecting portion 34. Projected. In addition, in the second end region of each link member 16, a pair of support shafts 38 are formed on the same side as the support shaft 36 from the outer surfaces of the both arm portions 30 and 32, and the both arm portions 30 and 32 are opposed to each other. A pair of support shafts 40 project from the side surface to the same side as the connecting portion 34 in a coaxial manner. Further, one arm portion 30 of each link member 16 is provided with one tooth 42 on the front end surface adjacent to the support shafts 38 and 40 in the second end region, and the other arm portion 32 is similarly configured. Two teeth 44 are provided on the tip surface adjacent to the support shafts 38 and 40.

  Each of the pair of link members 16 slidably fits the support shaft 36 provided in the base end region of each arm portion 30, 32 into the guide groove 22 a of each sliding engagement portion 22 of the base 12, and The support shafts 38 and 40 provided in the end regions of the arm portions 30 and 32 are rotatably engaged with the pair of bearing members 26 and 28 of the respective pivot mounting portions 24 of the key top 14, and the base 12 and the key It is arranged between the top 14. At this time, in the pair of link members 16, one tooth 42 of each one arm portion 30 and two teeth 44 of each other arm portion 32 are engaged with each other, whereby both arm portions 30, The rotation axes 46 (FIG. 3) shared by the 32 support shafts 38 and 40 can be rotated in conjunction with each other.

  Accordingly, in the key top 14, the pair of link members 16 swings in opposite directions in synchronization with the respective rotation axes 46, and the respective support shafts 36 slide in the substantially horizontal direction along the base 12. As a result, the operation surface 14a is translated in a substantially vertical direction with respect to the base 12 while maintaining a predetermined substantially horizontal posture in which the operation surface 14a is disposed substantially parallel to the main surface 12a. The upper limit position of the keystroke stroke of the key top 14 is a wall in which the sliding of the respective support shafts 36 of the pair of link members 16 in the mutual approaching direction defines the guide grooves 22a of the respective sliding engagement portions 22 of the base 12. Defined when locked by part. As the key top 14 is lowered from the upper limit position, the respective support shafts 36 of the pair of link members 16 slide in the mutually separating directions substantially perpendicular to the ascending / descending direction of the key top 14. When the key top 14 reaches the lower limit position of the key stroke, the pair of link members 16 are accommodated on the inner surface 14b side of the key top 14 and received in the central opening 20 of the base 12 (FIG. 3).

  The switch mechanism 18 includes a membrane switch 52 having a pair of sheet substrates 50 (only one contact 48 and one sheet substrate 50 are shown in FIG. 1), which are opposed to each other and supported by a pair of contacts 48, the key top 14, and the like. It is comprised between the membrane switch 52, and the action | operation member 54 which acts so that both the contacts 48 may be closed with the downward movement of the keytop 14 is comprised. Between the pair of sheet substrates 50 of the membrane switch 52, a spacer 56 (FIG. 5) is installed that supports the sheet substrates 50 at a predetermined interval and holds both the contacts 48 in an open state.

  Both sheet substrates 50 of the membrane switch 52 have a known flexible printed circuit board configuration, and contacts 48 that can be short-circuited to each other are provided on the surface of the film substrate. These sheet substrates 50 are supported on a support plate 58 under the base 12, and both contacts 48 are positioned at the approximate center of the central opening 20 of the base 12. The actuating member 54 is a dome-shaped member integrally formed from a rubber material, and is disposed in the center opening 20 of the base 12 with the dome top 54 a facing the key top 14. The actuating member 54 is arranged with the dome top portion 54a spaced above the upper sheet substrate 50 when there is no load. A columnar pressing portion (not shown) extending toward the sheet substrate 50 is formed on the inner surface of the dome top portion 54 a of the operating member 54.

  The contact 48 carried on the pair of sheet substrates 50 is normally held in an open state via the spacer 56 due to the essentially each sheet substrate 50, and is positioned below the pressing portion of the operating member 54. . When an external force in a direction approaching the sheet substrate 50 is applied to the dome top portion 54a of the operation member 54, the operation member 54 is elastically deformed, and the pressing portion presses the upper sheet substrate 50 from the outer surface, whereby a pair of contact points 48 is obtained. Close. In the illustrated embodiment, the operating member 54 is fixedly connected to a flexible sheet member 60 disposed between the base 12 and the upper sheet substrate 50 at the lower dome opening end 54b. . Alternatively, the operating member 54 can be directly connected to the upper sheet substrate 50 without using the sheet member 60.

  In the key switch device 10, when no external force is applied to the key top 14, the operating member 54 of the switch mechanism 18 is attached to the upper limit position (FIG. 5) where the key top 14 is separated vertically upward from the base 12 on the outer surface of the dome top 54 a. Support. At this time, the membrane switch 52 is in a state where the pair of contacts 48 are open. Further, when the key top 14 is pushed down by the operator's keystroke operation, the actuating member 54 is deformed while exerting an upward elastic biasing force on the key top 14, and the upper seat immediately before the key top 14 reaches the lower limit position. The contact 50 is closed by pressing the substrate 50 from the outer surface. When the pressing force on the key top 14 is released, the operating member 54 is elastically restored to return the key top 14 to the upper limit position, and the upper sheet substrate 50 is restored to open the contact 48.

  In the key switch device 10, as described above, the four pivots that rotatably support the two pairs of support shafts 38 and 40 formed in the second end region of each of the pair of link members 16 on the key top 14. A landing part 24 is provided. As shown in FIG. 2 and FIG. 4, the pair of bearing members 26, 28 constituting each pivotal attachment portion 24 is a rotation axis 46 of the second end region defined by the support shafts 38, 40 of each link member 16. The end regions of the arm portions 30 and 32 of each link member 16 are substantially sandwiched between the bearing members 26 and 28 in the direction of the rotation axis 46. That is, the bearing members 26 and 28 of each pivoting portion 24 are disposed to face the outer side surface and the inner side surface of the end region of each arm portion 30 and 32 of each link member 16 via a slight gap.

  The bearing members 26 and 28 of each pivotally mounted portion 24 respectively support the support shafts 38 and 40 provided on the respective arm portions 30 and 32 of each link member 16 so as to be rotatable. In the illustrated embodiment, the bearing members 26 and 28 are arranged on different sides with respect to the rotation axis 46 of the link member 16. As shown in FIGS. 5 and 6, each bearing member 26, 28 has a substantially semi-cylindrical bearing that is in sliding contact with the outer peripheral surface of each of the support shafts 38, 40 provided on each arm 30, 32. Surfaces 26a and 28a are formed. The bearing members 26 and 28 of the two pivotal portions 24 constituting each set have their bearing surfaces 26a and 28a arranged on the same circumferential surface with respect to a common axis 46 '(FIG. 2). Therefore, when the pivot shafts 38 and 40 of the arm portions 30 and 32 of the link member 16 are mounted on the pivot attachment portions 24, the bearing members 26 and 28 are supported by the respective bearing surfaces 26a and 28a. 40 is supported in a centered state with its pivot axis 46 aligned with axis 46 '.

  Each bearing member 26, 28 is further formed with an introduction surface 26b, 28b extending in a direction substantially perpendicular to the inner surface 14b and communicating with the bearing surfaces 26a, 28a in a tip region away from the inner surface 14b of the key top 14. . The introduction surfaces 26b, 28b of the two bearing members 26, 28 are arranged at some distance from the common axis 46 ', and cooperate with each other so that each link member 16 corresponding to each pivot portion 24 of the key top 14 has a corresponding position. It acts as an introduction portion when the support shafts 38 and 40 are inserted.

  In the key switch device 10 having the above-described configuration, a pair of bearing members 26 and 28 of each pivoting portion 24 provided on the key top 14 are coupled to each other by the bearing surfaces 26a and 28a. Acting in the same manner as the bearing holes of the pivot portions of the top, the support shafts 38 and 40 of the arm portions 30 and 32 of the link members 16 are rotatably supported. Furthermore, the introduction surfaces 26b, 28b of the bearing members 26, 28 of each pivot portion 24 work in cooperation with each other in the same manner as the notches of the pivot portions of the key top in the conventional key switch device. That is, when the key top 14 is assembled to the pair of link members 16 in the assembly process of the key switch device 10, the state shown in FIG. 3 in which both link members 16 are combined and placed at a predetermined position on the base 12 (see FIG. That is, in the state corresponding to the stroke lower limit position of the key top 14), the bearing members 26, 28 of the respective pivotally attached portions 24 of the key top 14 are moved to the support shafts 38, 40 of the respective arm portions 30, 32 of the corresponding link members 16. First, the support shafts 30 and 32 are first press-fitted between the introduction surfaces 26b and 28b of the bearing members 26 and 28 to elastically deform the bearing members 26 and 28, and snap into the bearing surfaces 26a and 28a. Insert. Thus, the key switch device 10 can exhibit the same ease of assembly as the conventional key switch device.

  Moreover, in the molding process of the key top 14, after the bearing members 26 and 28 of the respective pivotally mounted portions 24 are molded by a general simple structure mold (not shown) having no core, the key top 14 is molded. When detaching from the mold, the mold portions for forming the bearing surfaces 26a, 28a of the bearing members 26, 28 can be forcibly pulled out from the formed bearing members 26, 28 through their introduction surfaces 26b, 28b. . In this case, stress is individually and dispersively applied to the bearing members 26 and 28 of the respective pivotally attached portions 24. Therefore, the deformation of the bearing surfaces 26a and 28a of the respective bearing members 26 and 28 after the detachment of the mold is changed. This can be suppressed as much as possible as compared with the deformation that the bearing hole of each pivoting portion of the key top in the apparatus suffers. As a result, after the assembly of the key switch device 10 is completed, unnecessary gaps between the bearing surfaces 26a, 28a of the bearing members 26, 28 of each pivoting portion 24 and the support shafts 38, 40 of each link member 16 are reduced. The Therefore, according to the key switch device 10, it is possible to eliminate as much as possible undesirable rattling that may occur during keystroke operation of the keytop 14 while avoiding an increase in manufacturing cost due to the configuration of the mold of the keytop 14. Thus, an accurate contact opening / closing operation by a key-pressing operation can be realized.

  Further, the pair of bearing members 26 and 28 constituting each pivoting portion 24 of the key top 14 are arranged on both sides in the rotational axis direction of the end regions of the arm portions 30 and 32 of the link members 16, respectively. As described above, even when the pair of arm portions 30 and 32 of each link member 16 are bent in a direction approaching or separating from each other due to a molding error or the like, While the key top 14 is assembled to each link member 16, each pivot portion 24 corrects this bending, and as a result, the support shafts 38, 40 of each link member 16 are replaced with the bearing members 26, 28 of each pivot portion 24. It is possible to accurately fit the bearing surfaces 26a and 28a. Further, when the key top 14 is assembled to each link member 16, when a pressing force is applied to each of the support shafts 38, 40 from each pivoting portion 24, or upward from the base 12 to the key top 14 after assembly. When the external force is applied, the pair of arms 30 and 32 of each link member 16 is prevented from bending in the direction approaching or separating from each other by the bearing members 26 and 28, so The link members 16 can be assembled accurately and relatively easily, and inadvertent removal of the key tops 14 from the link members 16 can be effectively prevented.

  In particular, in the key switch device 10, the bearing members 26, 28 of the pivotally mounted portions 24 of the key top 14 are supported by the arm portions 30, 32 of the link members 16 by the substantially semi-cylindrical bearing surfaces 26 a, 28 a. Since the shafts 38 and 40 are supported half by half, when the key top 14 is assembled to both the link members 16, the force equivalent to elastically deforming each pivoting portion of the key top in the conventional key switch device. Thus, the bearing members 26 and 28 of each pivot portion 24 can be individually elastically deformed by a distributed stress load. Therefore, an increase in force required when assembling the key top 14 to both the link members 16 can be suppressed, and deterioration of assembling workability can be effectively prevented. In addition, each pivoting portion 24 of the key top 14 can prevent deformation of the bearing surfaces 26a and 28a of the bearing members 26 and 28 due to mold detachment as much as possible, and can reduce the force when the key top is assembled. Assuming that the increase can be suppressed as much as possible, each of the bearing members 26 and 28 has bearing surfaces 26a and 28a capable of supporting more than half of the support shafts 38 and 40 of the arm portions 30 and 32 of the link members 16. It can also be configured to have.

FIG. 7 shows a key switch device 70 according to an embodiment ( second embodiment ) of the present invention. The key switch device 70 has substantially the same configuration as that of the key switch device 10 shown in FIG. 1 except for the configuration of the key top 72 and the pair of link members 74, and therefore, corresponding components are denoted by common reference numerals. Therefore, the description is omitted. That is, the key switch device 70 is arranged on the base 12, the main surface 12 a of the base 12 so as to be movable in the up-and-down direction, and has a key top 72 having an operation surface 72 a to be tapped with a finger of an operator, and the key top 72 as a base. 12, a pair of link members 74 that guide and support in the up-and-down direction, a switch mechanism 18 that opens and closes contacts of the electric circuit corresponding to the up-and-down movement of the key top 72, and a support plate 58 that is disposed below the switch mechanism 18. And is configured.

  The key top 72 of the key switch device 70 has substantially the same configuration as the key top in the conventional key switch device. Therefore, two sets of pivoting portions 76 are formed on the inner surface 72b of the key top 72 so as to be juxtaposed in the left-right direction. Each pivot portion 76 is composed of a plate-like piece projecting upright from the inner surface 72b of the key top 72, and extends in a direction substantially perpendicular to the inner surface 72b through a bearing hole 76a penetrating in the plate thickness direction. And a notch 76b communicating with 76a. The two pivoting portions 76 constituting each set are arranged apart from each other by a distance that can be engaged with a second end region (described later) of each of the pair of link members 74 in the center region in the left-right direction of the inner surface 72b of the key top 72. The second end region of each link member 74 is rotatably supported. Furthermore, the pivoting portions 76 on the corresponding side in each set are aligned in the left-right direction on the inner surface 72 b of the key top 72.

  The pair of link members 74 have a configuration similar to the link member in the conventional key switch device. That is, the two link members 74 have substantially the same shape and dimensions as each other, and are connected to each other in a gear shape at one end thereof and are combined in an inverted V shape in side view. Each link member 74 is integrally provided with a pair of arm portions 78 and 80 extending in parallel with each other and a connecting portion 82 for connecting the arm portions 78 and 80 to each other. In the illustrated embodiment, the proximal end regions of both arm portions 78, 80 adjacent to the connecting portion 82 constitute the first end region of the link member 74, and the distal end regions of both arm portions 78, 80 remote from the connecting portion 82. Constitutes the second end region of the link member 74. In the first end region of each link member 74, a pair of support shafts 84 are coaxially projected from the outer surfaces of the arm portions 78, 80 away from each other to the opposite side of the connecting portion 82. In addition, in the second end region of each link member 74, a pair of support shafts 86 project from the outer surfaces of both arm portions 78 and 80 on the same side as the support shaft 84 in a coaxial manner. Further, one arm portion 78 of each link member 74 is provided with one tooth 88 on the distal end surface adjacent to the support shaft 86 in the second end region, and the other arm portion 80 is similarly provided with a support shaft. Two teeth 90 are provided on the tip surface adjacent to 86.

  Each of the pair of link members 74 slidably fits a support shaft 84 provided in the proximal end region of each arm portion 78, 80 into the guide groove 22a of each sliding engagement portion 22 of the base 12, and A support shaft 86 provided in the terminal region of each arm 78, 80 is rotatably fitted in a bearing hole 76 a of each pivot portion 76 of the key top 72, and is arranged between the base 12 and the key top 72. Is done. At this time, in the pair of link members 74, one tooth 88 of each one arm portion 78 and two teeth 90 of each other arm portion 80 are engaged with each other, whereby both arm portions 78, The rotary shafts 92 (FIG. 8) shared by 80 support shafts 86 can be rotated in conjunction with each other.

  As shown in enlarged views in FIGS. 8 and 9, in the key switch device 70, each of the pair of support shafts 86 provided in the second end region of each link member 74 has a straight line in a direction perpendicular to the rotation axis 92. One slit 94 extending in a shape is formed. The slit 94 of each support shaft 86 is arranged substantially parallel to the notch 76b provided in each pivotally attached portion 76 of the key top 72 when the key top 72 is at the lower limit position of the lifting stroke. It is positioned on the end surface in the axial direction of each support shaft 86 (FIG. 8). Further, while the key top 72 moves upward from the lower limit position of the lifting / lowering stroke, the slit 94 of each support shaft 86 corresponds to the inclination angle of the link member 74 with respect to the key top 72, and the notch of each pivot portion 76. It inclines with respect to 76b (FIG. 9). The depth of the slit 94 from the axial end surface of each support shaft 86 is determined by the external force applied to the outer peripheral surface of the support shaft 86 radially inward by the half portion 86a of the support shaft 86 divided and formed by the slit 94. Thus, the range is selected so that it can be elastically deformed relatively easily in a direction approaching each other.

  In the assembly process of the key switch device 70, when the key top 72 is assembled to the pair of link members 74, both the link members 74 are combined and placed in a predetermined position on the base 12 (that is, the key top 72 In the state corresponding to the stroke lower limit position), each pivoting portion 76 of the key top 72 is pressed from above onto each pivot 86 of the corresponding link member 74, and the pivot 86 is first press-fitted into the notch 76b. The elastic member 76 is elastically deformed, and is snapped into the bearing hole 76a. At this time, since the slits 94 of the respective support shafts 86 are disposed substantially in parallel with the notches 76b of the respective pivotally attached portions 76, both half-body portions 86a of the support shaft 86 pass through the notches 76b. It is elastically deformed relatively easily by receiving external forces in the directions approaching each other. Thereby, the outer diameter of the support shaft 86 in the direction in which the notch 76b is expanded is reduced, and as a result, the support shaft 86 can be fitted into the bearing hole 76a of the pivot attachment portion 76 with a force smaller than that of the related art.

  On the other hand, in the assembled key switch device 70, when the key top 72 receives an upward external force, for example, lifting its edge, the key top 72 moves upward from the stroke lower limit position by the urging of the operating member 54. Thereby, the slit 94 of each support shaft 86 is inclined with respect to the notch 76b of each pivoting portion 76. Therefore, even if such an external force is applied to each support shaft 86 via each pivot portion 76, each half portion 86 a of the pivot shaft 86 can easily pass through the notch 76 b of the pivot portion 76. Such deformation does not occur substantially. As a result, the support shaft 86 of the link member 74 is stably held in the bearing hole 76 a of the pivot portion 76 of the key top 72. Thus, according to the key switch device 70, the easy removal of the link member 74 from the key top 72 can be prevented without deteriorating the workability of assembling the key top 72 to both link members 74.

FIG. 10 shows a key switch device 100 according to a related technique ( third embodiment ) of the present invention. Since the key switch device 100 has substantially the same configuration as that of the key switch device 70 shown in FIG. 7 except for the configuration of the pair of link members 102, the corresponding components are denoted by the same reference numerals and described. Is omitted. That is, the key switch device 100 includes a base 12, a key top 72 disposed on the main surface 12a of the base 12 so as to be movable in the up-and-down direction, and a pair of links for guiding and supporting the key top 72 in the up-and-down direction on the base 12. The switch 102 includes a member 102, a switch mechanism 18 that opens and closes a contact of an electric circuit corresponding to the raising and lowering operation of the key top 72, and a support plate 58 that is disposed below the switch mechanism 18.

  The pair of link members 102 of the key switch device 100 has a configuration similar to the link member in the conventional key switch device. That is, the two link members 102 have substantially the same shape and size as each other, and are connected to each other in a gear shape at one end thereof and are combined in an inverted V shape in a side view. Each link member 102 integrally includes a pair of arm portions 104 and 106 extending in parallel to each other and a connecting portion 108 that connects the arm portions 104 and 106 to each other. In the illustrated embodiment, the proximal end regions of both arm portions 104 and 106 adjacent to the connecting portion 108 constitute a first end region of the link member 102, and the distal end regions of both arm portions 104 and 106 away from the connecting portion 108. Constitutes the second end region of the link member 102. In the first end region of each link member 102, a pair of support shafts 110 project from the outer surfaces of the arm portions 104 and 106 that are separated from each other on the opposite side of the connecting portion 108 in a coaxial manner. In addition, a pair of support shafts 112 are provided on the second end region of each link member 102 so as to protrude coaxially from the outer surfaces of both arm portions 104 and 106 to the same side as the support shaft 110. Further, one arm portion 104 of each link member 102 is provided with one tooth 114 on the tip surface adjacent to the support shaft 112 in the second end region, and the other arm portion 106 is similarly provided with a support shaft. Two teeth 116 are provided on the tip surface adjacent to 112.

  Each of the pair of link members 102 slidably fits the support shaft 110 provided in the proximal end region of each arm portion 104, 106 into the guide groove 22a of each sliding engagement portion 22 of the base 12, and The support shaft 112 provided in the terminal region of each arm portion 104, 106 is rotatably fitted in the bearing hole 76 a of each pivoting portion 76 of the key top 72 and is disposed between the base 12 and the key top 72. Is done. At this time, in the pair of link members 102, one tooth 114 of each one arm portion 104 and two teeth 116 of each other arm portion 106 are engaged with each other, whereby both arm portions 104, The rotary shafts 118 (FIG. 11) shared by the support shafts 112 of the 106 can be rotated in conjunction with each other.

  In the key switch device 100, the connecting portion 108 of each link member 102 is substantially attached to the other member while moving along the base 12 according to the sliding motion of the support shaft 112 provided in the terminal region of each arm portion 104, 106. It has a shape that does not touch. That is, as shown in FIG. 11, the connecting portion 108 of each link member 102 has an outer surface 108 a that drops and spreads through a step with respect to the outer surface of the peripheral portion of the support shaft 110 of both arm portions 104 and 106. As a result, the first end region of the link member 102 is moved while the support shaft 110 of each link member 102 moves within the guide groove 22a of each sliding engagement portion 22 of the base 12 in response to the lifting operation of the key top 72. The outer surface of the peripheral portion of the support shaft 110 is in contact with the sheet member 60 that connects the base 12 and the actuating member 54 and slides while receiving frictional resistance. A gap is formed between them due to the shape of the outer surface 108 a of the connecting portion 108. Therefore, according to the key switch device 100, the frictional resistance due to the sliding between the pair of link members 102 and the sheet member 60 carrying them is reduced during the raising / lowering operation of the key top 72. The keystroke operation can be performed smoothly and accurately.

  Although not shown, in the configuration in which the actuating member 54 is directly connected to the upper sheet substrate 50 without using the sheet member 60, the peripheral portions of the two support shafts 110 of the link member 102 during the up-and-down operation of the key top 72. While the outer surface of the contact member contacts the base 12 and the sheet substrate 50 above the membrane switch 52 and slides while receiving frictional resistance, the connecting portion 108 of the link member 102 does not contact the sheet substrate 50. Accordingly, similarly, the frictional resistance due to sliding between the pair of link members 102 and the membrane switch 52 carrying them is reduced during the raising / lowering operation of the key top 72, so that the key top 72 can be moved smoothly and accurately. Keystrokes can be operated. Although not shown, even in a configuration in which a part of the base 12 extends below the first end region of each link member, the link member 102 has a connecting portion 108 that does not contact such an extended portion of the base 12. By adopting the key top 72, the keystroke operability of the key top 72 can be improved.

  The link member 102 of the key switch device 100 is not limited to the connecting portion 108 having the above-described shape, and for example, an arch-shaped connecting portion 108 ′ shown as a modification in FIG. 12 can be employed. In addition, as shown in FIG. 13, a connecting portion 108 ″ can be formed at a position slightly shifted from the first end region to the second end region side of the link member 102. In any case, the connecting portion 108 ″ can be formed. 108 ′ and 108 ″ do not substantially contact other members such as the membrane switch 52 and the sheet member 60 while moving along the base 12 along with the support shaft 112 of each arm 104 and 106. This acts to improve the keystroke operability of the key top 72 by reducing the frictional resistance caused by sliding between the link member 102 and other members.

  FIG. 14 shows still another modification of the key switch device 100. In this modification, each of the membrane switch 52 and the sheet member 60 has a through hole at a position where the support shaft 110 in the first end region of the link member 102 having the connecting portion 108 ″ as shown in FIG. 13 slides. 120 and 122. Therefore, in this modified example, the pair of support shafts 110 provided in the first end region of each link member 102 is formed in the through hole 122 of the sheet member 60 during the lifting and lowering operation of the key top 72. And through the through hole 120 of the membrane switch 52 and slides on the surface of the support plate 58 below them, and the connecting portion 108 ″ of each link member 102 moves to the sheet member 60 in a non-contact manner. Thus, frictional resistance due to sliding between each link member 102 and the sheet member 60 is reduced.

  In the configuration of the present invention exemplified by the key switch devices 10, 70, 100 according to the above-described embodiments, a pair of link members, which is one of the constituent elements, is replaced with the link members 16, 74, 102 having the above-described gear link structure. The present invention is not limited, and can be applied to a key switch device including link members having various other structures. As such another pair of link members, those combined in an X shape in a side view and connected to each other at an intersection (see, for example, Japanese Utility Model Publication No. 5-66832), in an X shape in a side view. Examples are those that are combined and slidably connected to each other at the intersection (see, for example, JP-A-9-27235).

FIG. 15 shows a key switch device 130 according to a related technique ( fourth embodiment ) of the present invention. The key switch device 130 includes a base 132, a key top 134 having an operation surface 134 a that is arranged on the main surface 132 a of the base 132 so as to be movable in the up-and-down direction and can be pressed with the fingers of the operator, and the key top 134 is the base 132. A guide support member 136 that guides and supports in the up-and-down direction above, a switch mechanism 138 that opens and closes contacts of the electric circuit corresponding to the up-and-down movement of the key top 134, and a support plate 140 that is disposed below the switch mechanism 138. It is prepared for. The base 132, the key top 134, and the switch mechanism 138 basically have the same configuration as the base 12, the key top 14, and the switch mechanism 18 in the key switch device 10 of FIG.

  The base 132 is integrally provided with a hollow sleeve 144 that protrudes from the main surface 132 a and defines a central opening 142. The key top 134 is provided with a columnar slider 146 slidably received by the sleeve 144 of the base 132 on the inner surface opposite to the operation surface 134a. The sleeve 144 and the slider 146 function as a guide support member 136 in cooperation with each other. The switch mechanism 138 is disposed between a membrane switch 152 having a pair of sheet substrates 150 that carry a pair of contacts 148 facing each other, and between the key top 134 and the membrane switch 152, so that the key top 134 can be lowered. Along with this, a dome-shaped actuating member 154 that acts to close both contacts 148 is formed. A spacer 156 is installed between the pair of sheet substrates 150 of the membrane switch 152 to support the sheet substrates 150 at a predetermined interval and hold both the contacts 148 in an open state. The actuating member 154 is directly connected to the upper sheet substrate 150 at the lower end dome opening end 154b.

  In the key switch device 130, when no external force is applied to the key top 134, the actuating member 154 of the switch mechanism 138 is on the outer surface of the dome top portion 154a, and the key top 134 is separated vertically upward from the base 132 via the slider 146. Energize and support the upper limit position. At this time, the membrane switch 152 is in a state where the pair of contacts 148 are opened. When the key top 134 is pushed down by the operator's keystroke operation, the actuating member 154 is deformed while exerting an upward elastic biasing force on the key top 134 via the slider 146, and the key top 134 reaches the lower limit position. Immediately before, the upper sheet substrate 150 is pressed from the outer surface to close the contact 148. When the pressing force on the key top 134 is released, the operating member 154 is elastically restored to return the key top 134 to the upper limit position, and the upper sheet substrate 150 is restored to open the contact 148.

  The support plate 140 is brought into contact with the outer surface of the sheet substrate 150 on the lower side of the membrane switch 152 and constitutes a support structure of the key switch device 130. On the surface of the support plate 140 on the side facing the lower sheet substrate 150, the contact 148 and the dome opening end 154 b are located at positions corresponding to the pair of contacts 148 of the membrane switch 152 and the dome opening end 154 b of the actuating member 154. A plurality of projecting portions 158 having a shape and a size capable of supporting the two in a fixed manner are formed. Accordingly, a gap 160 is formed between the support plate 140 and the membrane switch 152 at least in a region near the contact 148 inside the dome opening end 154 b of the operating member 154. In the illustrated embodiment, a gap 160 is similarly formed between the support plate 140 and the membrane switch 152 in the outer region of the dome opening end 154 b of the operating member 154. However, the outer region may be configured such that the support plate 140 contacts the membrane switch 152 by eliminating the gap 160 when the presence of dust is predicted not to adversely affect the contact opening / closing operation. .

  In the key switch device 130 having the above-described configuration, the support plate 140 receives elastic force applied to the membrane switch 152 from the key top 134 via the operating member 154 when the key top 134 is pressed by the plurality of protruding portions 158. At the same time, the operating member 154 can receive a pressing force when closing the contact 148 of the membrane switch 152. In addition, since a gap 160 is formed between the support plate 140 and the membrane switch 152 in the vicinity of the contact point 148, even when dust adheres to the surface of the support plate 140 within the gap 160. It is avoided that dust affects the accurate and stable opening / closing operation of the contact 148. Therefore, the key switch device 130 can be assembled in a normal assembly process without using expensive equipment such as a clean room, and at that time, dust that adversely affects the opening / closing operation of the contact 148 of the membrane switch 152. Can be reduced between the membrane switch 152 and its support structure.

  The support plate 140 of the key switch device 130 can be made of a metal member installed on the lower resin casing of the keyboard into which the key switch device 130 is incorporated. The resin lower casing itself of the keyboard can be configured as the support plate 140 without the metal support plate. Further, as the guide support member 136 which is one constituent element of the key switch device 130, a configuration including a pair of link members 16 as shown in FIG. 1 and the link members having other various configurations described above instead of the above structure. It can also be.

  FIG. 16 shows a keyboard 170 according to an embodiment of the present invention having a number of key switch devices 10 of FIG. 1 as an example. The keyboard 170 is configured by including a number of key switch devices 10 having key tops 14 of various shapes in a predetermined arrangement. In the keyboard 170, all the key switches in which the base 12, the membrane switch 52 (the sheet substrate 50 and the spacer 56), the sheet member 60 to which the operation member 54 is fixed, and the support plate 58 in the key switch device 10 are all incorporated in the keyboard 170. It is formed as a large base 12 ', a membrane switch 52', a sheet member 60 'and a support plate 58' common to the apparatus 10. In addition, a keyboard can be similarly configured by arranging a large number of key switch devices 70, 100, and 130 according to the other embodiments described above. Such a keyboard is very excellent in assembling workability and operability.

10, 70, 100, 130 Key switch device 12, 132 Base 14, 72, 134 Key top 16, 74, 102 Link member 18, 138 Switch mechanism 24 Pivoting portion 26, 28 Bearing member 36, 38, 40, 84, 86, 110, 112 Support shaft 52, 152 Membrane switch 54, 154 Actuating member 58, 140 Support plate 60 Sheet member 94 Slit 158 Protruding portion 160 Clearance 170 Keyboard

Claims (2)

A base and a key top disposed on the base, each of which interlocks with each other and operatively engages both the base and the key top to guide and support the key top on the base in the up-and-down direction. A key switch device comprising a pair of link members and a switch mechanism that opens and closes a contact of an electric circuit in response to a lifting operation of the key top.
Each of the pair of link members includes a first end region that is slidably engaged with the base, and a second end region that is rotatably engaged with the key top, and the second end region includes The support shaft extends along the rotation axis, extends in a direction intersecting the rotation axis on the axial end surface of the support shaft, and deepens from the end surface in the direction of the rotation axis. A slit having a thickness is formed , and a pair of half-body parts divided by the slit is formed on the support shaft ,
The key top includes a plurality of pivot portions having bearing holes for rotatably supporting the support shafts of the pair of link members, and extends substantially parallel to each of the pivot portions. A notch communicating with the bearing hole is provided,
When the key top is at the lower limit position of the lifting / lowering stroke, the slit formed in the support shaft of each of the link members substantially corresponds to the notch provided in each of the pivotally attached portions of the key top. Arranged in parallel, the pair of half-portions are elastically deformed in a direction approaching each other, and the pivoting portion is elastically deformed so that the support shaft can pass through the notch,
When the key top moves upward from the lower limit position, the slit is disposed to be inclined with respect to the notch, and the pair of half-portions does not deform to pass through the notch. Configured as
A key switch device characterized by.   A keyboard configured by arranging a number of key switch devices according to claim 1.

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