Switch unit, key switch device, and keyboard

Abstract

To provide a switch unit, a key switch device, and a keyboard that allow for replacement of a key top and can provide a good sense of touch for a user without significantly changing the whole height.SOLUTION: A key switch unit 101 includes: a slider 2 that can be slid by a depressing operation on a key top 1; and a housing 5 that supports the slider 2. An electric contact point 71 is opened and closed in response to sliding of the slider 2. The slider 2 comprises: a pedestal part 22; a projection 21 that is provided on a depressing operation side of the pedestal part along a sliding direction of the slider and on which the key top is mounted; and a column part 23 that is provided on the side of the pedestal part opposite to the depressing operation side along the sliding direction. The housing 5 comprises: a plate part 51; and a guide 52 that is provided on the depressing operation side of the plate part along the sliding direction. The pedestal part includes a through hole 22a through which the guide is passed. The guide includes a through hole 54 into which the column part is inserted.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a switch unit, a key switch device, and a keyboard.

Background Art

[0002] Conventionally, there has been known a key switch device including a key top that is pressed downward, a slider press-fitted to the lower surface of the key top, a rubber that elastically buckles and deforms by pressing the key top and applies a repulsive force corresponding to the elastic buckling deformation to the slider, and a contact pressing member that is provided so as to be relatively movable with respect to the slider and adds a pressing force independent of the operating force of the key top to a membrane switch.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Keyboards with replaceable key tops are widely distributed in the market, and replacement key tops are also available. On the back surface of the replacement key top, there is formed a recess for detachably attaching, for example, a cross-shaped protrusion provided on the key switch side.

[0005] In the key switch device of Patent Document 1, since a protrusion for making the key top detachable is not formed on the upper surface of the slider and the slider is press-fitted to the lower surface of the key top, a replacement key top cannot be attached.

[0006] In addition, if a protrusion such as a cross shape is provided on the upper surface of the slider of Patent Document 1, the overall height of the key switch device increases, and there is a risk of burdening the wrist in a keyboard in which a plurality of key switch devices are arranged.

[0007] Therefore, there is a need for a switch unit, a key switch device, and a keyboard in which the operating member is replaceable and which can provide a good feel to the user without significantly changing the overall height. In addition, there is a need for a switch unit, a key switch device, and a keyboard that can be collectively attached to the member to be attached without disassembling the switch unit.

Means for Solving the Problems

[0008] A switch unit according to one aspect of the present disclosure is capable of mounting an operating member, and includes a sliding member that is slidable by a pressing operation of the operating member, and a support member that supports the sliding member, and is a switch unit for opening and closing an electrical contact in response to the sliding of the sliding member. The sliding member includes a pedestal portion, a first protrusion provided on the pressing operation side along the sliding direction of the sliding member from the pedestal portion and capable of mounting the operating member, and a support column portion provided on the side opposite to the pressing operation side along the sliding direction from the pedestal portion. The support member includes a plate portion and a first guide portion provided on the pressing operation side from the plate portion along the sliding direction. The pedestal portion has a first through hole through which the first guide portion passes, and the first guide portion has a second through hole into which the support column portion is inserted.

[0009] A switch unit according to another aspect of the present disclosure is capable of mounting an operating member, and includes a sliding member that is slidable by a pressing operation of the operating member, a first elastic member that is mounted on the sliding member and elastically deforms in response to the pressing operation of the operating member, a second elastic member that is mounted on the sliding member and opens and closes an electrical contact in response to the sliding of the sliding member, a plate portion having a first surface and a second surface on the opposite side of the first surface, a first guide portion erected on the first surface of the plate portion for guiding the sliding member, a second guide portion erected on the first surface of the plate portion and provided outside the first guide portion when the plate portion is viewed from above for guiding the first elastic member, and a support member having legs erected on the second surface of the plate portion.

Advantages of the Invention

[0010] According to one aspect of the present disclosure, the operating member is replaceable and can provide a good feel to the user without significantly changing the overall height. Further, according to another aspect of the present disclosure, the switch unit can be collectively attached to the member to be attached without disassembling it.

Brief Description of the Drawings

[0011]

Fig. 1

Fig. 2

Fig. 3

Fig. 4

Fig. 5

Fig. 6

Fig. 7

Fig. 8

Fig. 9

Fig. 10

Fig. 11

Fig. 12

Fig. 13

Embodiments for Carrying Out the Invention

[0012] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0013] [First Embodiment] FIG. 1(A) is a perspective view showing the overall configuration of a key switch device 100 according to the first embodiment, and FIG. 1(B) is an exploded perspective view of the key switch device 100. FIGS. 2(A) and (B) are cross-sectional views taken along line A-A of the key switch device 100 of FIG. 1(A), FIG. 2(A) represents a state where the key top is not pressed, and FIG. 2(B) shows a state where the key top is pressed.

[0014] In FIG. 1(B), a switch unit 101 is composed of a slider 2 (a sliding member) on which a key top 1 is mounted and slides in the vertical direction, a dome rubber 3 (a first elastic member) that elastically buckles and deforms by pressing the key top 1 and applies a repulsive force corresponding to the elastic buckling deformation to the slider 2, a spring 4 (a second elastic member) that is mounted on the slider 2 and presses an electrical contact such as a membrane switch 7 or a mechanical switch (not shown), and a housing 5 (a supporting member) to which the slider 2 is attached and that supports the vertical sliding of the slider 2. The switch unit 101 is provided with a switch panel 6 (a member to be mounted), which is a positioning member that determines the positions of the aforementioned key top 1 and housing 5, a membrane switch 7 that is disposed under the housing 5 and the switch panel 6 and has electrical contacts, and a support panel 8 that is disposed under the membrane switch 7 and fixes the switch panel 6, thereby constituting a key switch device 100.

[0015] The key top 1 is integrally formed with resin as a constituent material. On the back surface of the key top 1, a recess 11 for attachment to a cross-shaped protrusion (to be described later) of the slider 2 is formed (see FIG. 2(A)).

[0016] FIGS. 3(A) and (B) are perspective views of the slider 2, and FIG. 3(C) is a cross-sectional view taken along line B-B of the slider 2 in FIG. 3(A).

[0017] The slider 2 includes a cross-shaped protrusion 21 (a first protrusion), a columnar pedestal portion 22, and a prismatic support portion 23. The protrusion 21, the pedestal portion 22, and the support portion 23 are integrally formed on the same axis along the sliding direction by a pressing operation. The protrusion 21 is provided on the pedestal portion 22 on the pressing operation side, and the support portion 23 is provided inside the pedestal portion 22 so as to extend on the opposite side of the pressing operation. The upper end of the support portion 23 is substantially the same as the upper end of the pedestal portion 22, and the lower part of the support portion 23 is exposed from the pedestal portion 22.

[0018] The pedestal portion 22 is provided with an outer peripheral surface 29 into which the dome rubber 3 is press-fitted on its cylindrical side surface, and includes a plurality of connecting portions 22b as beams connecting the column portion 23 and the side surface. A through hole 22a (first through hole) for passing the guide 52 of the housing 5 described later is provided in a region surrounded by the plurality of connecting portions 22b and the side surface. The connecting portion 22b transmits the pressing force from the key top 1 transmitted to the projection 21 to the dome rubber 3.

[0019] As shown in FIG. 3(B), a part of the outer periphery of the lower surface of the pedestal portion 22 is formed with an extension portion 27 extending vertically downward, and a projection 28 (second projection) protruding radially inward is formed at the lower portion of the extension portion 27. The projection 28 engages with a groove portion 55 formed in the guide 52 described later, and is provided so that the slider 2 does not rotate with respect to the housing 5 and the slider 2 does not come out of the groove portion 55 (see FIG. 4) of the housing 5. Thereby, rattling of the key switch device 100 due to rotation of the slider 2 can be prevented.

[0020] Further, the vertical length L0 of the extension portion 27 (see FIG. 3(B)) is set so that when the key top 1 is not pressed, the position of the upper surface of the pedestal portion 22 or the connecting portion 22b is substantially the same as the position of the upper end of the guide 52 in a state where the projection 28 engages with the groove portion 55 of the housing 5. Here, substantially the same means that a deviation due to a manufacturing error in the position of the upper surface of the pedestal portion 22 or the connecting portion 22b and the upper end of the guide 52 is determined to be the same.

[0021] For example, when the key top 1 is not depressed, if the protrusion 28 is engaged with the groove portion 55 of the housing 5 and the position P1 (see FIG. 2(A)) of the upper surface of the pedestal portion 22 or the connecting portion 22b is higher than the position P2 of the upper end of the guide 52, the overlapping distance between the support portion 23 and the guide 52 in the vertical direction becomes short, so rattling is likely to occur. On the other hand, when the key top 1 is not depressed, if the protrusion 28 is engaged with the groove portion 55 of the housing 5 and the position P1 of the upper surface of the pedestal portion 22 or the connecting portion 22b is lower than the position P2 of the upper end of the guide 52, the distance from the upper end of the guide 52 to the key top 1 becomes short, so the key stroke cannot be ensured sufficiently.

[0022] Therefore, in the first embodiment, when the key top 1 is not depressed, with the protrusion 28 engaged with the groove portion 55 of the housing 5, the vertical length L0 of the extension portion 27 is set so that the position P1 of the upper surface of the pedestal portion 22 or the connecting portion 22b is substantially the same as the position P2 of the upper end of the guide 52. Therefore, rattling can be suppressed while ensuring the key stroke.

[0023] The support portion 23 is inserted into a through-hole 54 (see FIG. 4(A)) of the guide 52 described later, and guides the vertical sliding of the slider 2 together with the through-hole 54. Since the support portion 23 and the through-hole 54 are substantially rectangular in cross-section, rattling in the rotational direction can be suppressed.

[0024] As shown in FIG. 3(C), an opening 24 is formed in the support portion 23 downward, and a protrusion 25 for fixing the spring 4 is formed inside the support portion 23. A part of the spring 4 is inserted and fixed between the inner surface 26 of the support portion 23 and the protrusion 25.

[0025] When the key top 1 is not depressed, a part of the spring 4 is disposed below the lower end of the support portion 23. In other words, when the key top 1 is not depressed, the vertical length L2 of the spring 4 is longer than the vertical length L1 of the opening 24 (see FIG. 2(A)). This is because the spring 4 presses the electrical contact when the key top 1 is depressed.

[0026] As shown in FIG. 2(B), the distance D1 from the upper end of the guide 52 to the contact point of the membrane switch 7 is greater than the vertical thickness H1 of the slider 2 (i.e., the protrusion 21 and the support portion 23). When the distance D1 from the upper end of the guide 52 to the contact point of the membrane switch is smaller than the vertical thickness H1 of the slider 2, when the key top 1 is not pressed, the distance at which the support portion 23 and the guide 52 overlap in the vertical direction becomes shorter, and rattling is likely to occur. Therefore, in the first embodiment, the distance D1 is set to be greater than the thickness H1.

[0027] Returning to FIG. 1(B), the dome rubber 3 is a dome-shaped member integrally formed from a rubber material, and has a ring-shaped base portion 31, a dome portion 32 that rises in a dome shape from the base portion 31, and a cylindrical portion 33 that extends upward from the top of the dome portion 32. The cylindrical portion 33 is press-fitted from below onto the outer peripheral surface 29 of the pedestal portion 22 of the slider 2 and is attached to the outer peripheral surface 29. The pedestal portion 22 of the slider 2 operates integrally with the cylindrical portion 33.

[0028] The slider 2 and the housing 5 are formed of different materials with little friction when they come into contact. For example, the slider 2 is formed of POM resin (polyacetal resin), and the housing 5 is formed of ABS resin (a thermoplastic resin made by polymerizing three monomers: acrylonitrile, butadiene, and styrene). This is because if the slider 2 and the housing 5 are formed of the same material, the slider 2 will bite into the guide 52 during sliding, and a stack will occur where the key top 1 cannot move. For this reason, the slider 2 and the housing 5 are formed of different materials with little friction when they come into contact. Note that the materials of the slider 2 and the housing 5 are not limited to resins. Processing may be performed to reduce the friction coefficient at the contact portions of the slider 2 and the housing 5 so that the friction is small when they come into contact.

[0029] FIGS. 4(A) and (B) are perspective views of the housing 5, and FIG. 4(C) is a side view of the housing 5 as viewed from the Y direction.

[0030] The housing 5 is a member that supports the slider 2 and the dome rubber 3, and has a square plate portion 51 that constitutes the base substrate, and a guide 52 (first guiding portion) that stands upright upward from the center of the plate portion 51. A through hole 54 (second through hole) having a substantially rectangular cross section for inserting the column portion 23 of the slider 2 is opened at the center of the guide 52. Further, a slit 53 is provided in the guide 52 so that the connecting portion 22b of the slider 2 does not interfere with the guide 52 when the slider 2 slides.

[0031] As shown in FIG. 2(A), the vertical length L3 of the slit 53 is substantially the same as the vertical thickness T2 of the column portion 23 of the slider 2, and is larger than the vertical thickness T3 of the protrusion 21 of the slider 2. Here, "substantially the same" means that the deviation due to manufacturing error is judged to be the same. In this case, since a sufficient distance for the column portion 23 and the guide 52 to overlap in the vertical direction can be ensured, rattling can be suppressed.

[0032] Further, as shown in FIG. 2(B), when the key top 1 is pressed and located at the lowermost position, the upper end of the slider 2 (that is, the upper end of the protrusion 21) is at substantially the same height as the upper end of the guide 52 or is located below the upper end of the guide 52. In this case, during the sliding of the slider 2, the protrusion 21 enters the through hole 54, so that the protrusion 21 for mounting the key top 1 can be provided without significantly changing the overall height of the key switch device 100 while ensuring the key stroke.

[0033] Returning to FIG. 4(A), a groove portion 55 that extends along the vertical direction is formed at the lower portion of the guide 52, and the protrusion 28 of the slider 2 is engaged therewith. For example, when the key top 1 is pressed, the protrusion 28 of the slider 2 descends within the groove portion 55, and when the pressing of the key top 1 ends, the protrusion 28 of the slider 2 ascends within the groove portion 55.

[0034] Since the groove portions 55 are provided in four directions, the protrusion 28 of the slider 2 can be inserted into the groove portions 55 even when the slider 2 is rotated by 90 degrees. Therefore, the degree of freedom during the assembly of the key switch device 100 is increased, and the workability can be improved. Note that the groove portions 55 may be through holes, or through holes may be formed in a part of the groove portions 55. Thereby, light such as the LED 70 described later can irradiate the key top 1 through the gap between the slider 2 and the guide 52 via this through hole.

[0035] The plate portion 51 is provided with a through hole 56 (third through hole) for arranging a light source such as the LED 70. The through hole 56 is formed at a position facing the guide 52 in the radial direction. FIG. 5 is a cross-sectional view of the key switch device 100 when the LED 70 is arranged in the through hole 56. In FIG. 5, the key top 1 and the support panel 8 are omitted.

[0036] When the light source arranged in the through hole 56 emits light, the light passes through various paths. For example, some of the light passes through the dome rubber 3. At this time, since the light is diffused by the dome rubber 3, the entire area around the key top 1 can be illuminated. Since the overall height of the key switch device 100 is not significantly changed as described above, the attenuation of the light to the key top 1 can be suppressed. Also, by simply changing the color of the dome rubber 3, the color of the light source is not changed, and the variations in the illumination color can be increased. Thereby, since the types of LEDs used for the light source can be reduced, the types of components can be reduced.

[0037] In addition, some of the other light is reflected by the dome rubber 3 and irradiates the key top 1 through the gap between the slider 2 and the guide 52 via the slit 53. Further, when a through-hole is provided in the groove portion 55 as described above, some of the other light irradiates the key top 1 through the gap between the slider 2 and the guide 52 via the through-hole in the groove portion 55. In these cases, the light of the light source can be taken in from the slit 53 or the through-hole in the groove portion 55, and the amount of light reaching the key top 1 can be increased. For example, if the entire key top 1 is transparent, the key top 1 itself appears to emit light, and if the character portion of the key top 1 is transparent, the character portion of the key top 1 appears to emit light.

[0038] Returning to Fig. 4(A), outside the through-hole 56 of the plate portion 51, a protrusion 57 (second guiding portion) for fitting the base portion 31 of the dome rubber 3 is provided. Further, on the back surface of the plate portion 51, a leg portion 59 that can attach the housing 5 to the opening 61 of the switch panel 6 is erected, and the leg portion 59 is formed with a claw portion 58 for sandwiching the switch panel 6 between the back surface of the plate portion 51. Since the plate portion 51 of the housing 5 is square, it can be easily fixed to the square opening 61 of the switch panel 6 even when rotated 90 degrees. Therefore, the degree of freedom during the assembly of the key switch device 100 is increased, and the workability can be improved.

[0039] Returning to Fig. 2(A), the membrane switch 7 includes electrical contacts 71. The electrical contacts 71 are disposed below the housing 5 and the switch panel 6 and are closed when a predetermined pressing force acts from the spring 4 due to the pressing of the key top 1. In the first embodiment, the membrane switch 7 is used, but it is not particularly limited as long as it is a switch having electrical contacts. For example, a mechanical switch may be employed instead of the membrane switch 7.

[0040] The switch panel 6 is arranged on the membrane switch 7 and the support panel 8, and is fixed to the support panel 8 by screws (not shown) or the like to a spacer 62 provided below the switch panel 6. As shown in Fig. 1(B), the shape of the opening 61 of the switch panel 6 is square, and when the housing 5 is fixed to the opening 61, the opening 61 is covered by the plate portion 51 of the housing 5. A space 40 of a predetermined height is formed between the switch panel 6, the membrane switch 7, and the support panel 8 by the spacer 62 (see Fig. 2(A)). And in a plan view, the area of the plate portion 51 is larger than the area of the opening 61 of the switch panel 6. Therefore, by simply inserting the leg portion 59 of the housing 5 into the opening 61 of the switch panel 6, the slider 2, the dome rubber 3, the spring 4, and the housing 5 can be attached to the switch panel 6 together without being separated.

[0041] Also, the slider 2, the dome rubber 3, the spring 4, and the housing 5 integrally form a switch unit 101. By inserting the leg portion 59 of the housing 5 into the opening 61 of the switch panel 6, the switch unit 101 is fixed to the opening 61 of the switch panel 6 from above. Thereby, by simply inserting the leg portion 59 of the housing 5 into the opening 61 of the switch panel 6, the user can easily attach the switch unit 101 with the desired pressing characteristics to the switch panel 6. Also, the user can replace the switch unit 101 mounted on the switch panel 6 for each switch unit.

[0042] In a conventional key switch device, a slider and a dome rubber with a spring attached to the front surface side of a switch panel are arranged, a housing is arranged on the back surface side of the switch panel, and the switch panel is sandwiched between the slider and the dome rubber and the housing. It is necessary to separately attach the slider and the dome rubber with the spring and the housing to the switch panel, and the attachment work to the switch panel is complicated. On the other hand, the switch unit 101 in the present embodiment integrates the slider 2, the dome rubber 3, the spring 4, and the housing 5 and can be attached to the switch panel 6 from above, so that the attachment work to the switch panel 6 can be easily performed.

[0043] In the first embodiment, since the key top 1 is replaceable and the insertion and removal of the key top 1 occur, when the key top 1 is pulled out, the switch unit 101 may be pulled out from the switch panel 6. For this reason, it is preferable that the leg portion 59 includes a claw portion 58 that sandwiches the switch panel 6 between the back surface of the plate portion 51. Thereby, the claw portion 58 contacts the switch panel 6, and it is possible to prevent the switch unit 101 from being pulled out from the switch panel 6 from above.

[0044] FIG. 6 is a diagram showing the depression characteristics of the key switch device 100 according to the first embodiment. The horizontal axis represents the stroke S (depression amount) of the key top 1, and the vertical axis represents the operating force (depression force) F. Point a in FIG. 6 indicates contact on.

[0045] As shown in FIG. 6, as the operating force F of the key top 1 increases, the stroke S also increases accordingly. At this time, the dome rubber 3 is elastically deformed, and a reaction force from the dome rubber 3 acts on the key top 1. The depression characteristics in this case are equal to the load-displacement characteristics of the dome rubber 3 itself. The operating force F increases until the load acting on the dome rubber 3 reaches the buckling load of the dome rubber 3, and when the buckling load is reached, thereafter, the operating force F gradually decreases as the stroke S increases. By obtaining the peak operating force F0 due to the elastic buckling deformation of the dome rubber 3, the user can obtain a click feeling peculiar to the key operation.

[0046] In the first embodiment, the stroke S1 at the time of contact closing is set to a value that is larger than the stroke S0 at which the peak operating force F0 is generated and smaller than the end stroke S2 (for example, the middle of S0 and S2). In this way, in the key switch device 100, since the spring 4 opens and closes the contacts of the membrane switch 7 while the operating force F generated during the buckling deformation of the dome rubber 3 is decreasing, there is no deviation between the operating feeling and the contact closing operation, and a good feeling can be provided to the user.

[0047] The above key switch device 100 is disposed, for example, on a keyboard. FIG. 7 is a perspective view of a keyboard 201 according to the first embodiment including a large number of key switch devices 100. The keyboard 201 includes an upper cover 9, a lower cover 10, and a plurality of key switch devices 100. In this keyboard 201, the switch panel 6, the membrane switch 7, and the support panel 8 in the key switch device 100 are formed to expand horizontally over the entire keyboard and are shared for each key switch device 100.

[0048] The key switch device 100 according to the first embodiment is applicable as an input device such as a ticket vending machine, an ATM, or a kiosk terminal. Further, when the key switch device 100 is used alone, the switch panel 6 may not be provided. In this case, a screw hole may be provided in the housing 5, and the housing 5 may be screwed to the support panel 8 via the membrane switch 7.

[0049] As described above, according to the first embodiment, in the key switch device 100, the slider 2 includes a pedestal portion 22, a protrusion 21 provided on the pedestal portion 22 and capable of mounting the key top 1, and a support portion 23 provided below the pedestal portion 22. The housing 5 includes a plate portion 51 and a guide 52 that stands upright upward from the center of the plate portion 51. The pedestal portion 22 has a through hole 22a that passes through the guide 52 of the housing 5, and the guide 52 has a through hole 54 into which the support portion 23 of the slider 2 is inserted.

[0050] With this configuration, the guide 52 can pass through the slider 2 via the through-hole 22a, and interference with the connecting portion 22b of the slider 2 can be avoided by the slit 53 of the guide 52. Therefore, when the slider 2 slides, the protrusion 21 on which the key top 1 can be mounted can enter the through-hole 54 surrounded by the guide 52. As a result, a protrusion 21 for mounting the key top 1 can be provided without significantly changing the overall height of the key switch device 100, and furthermore, since the pressing force can be transmitted from the key top 1 to the dome rubber 3, a good feel can be provided to the user.

[0051] Also, since the overall height of the key switch device 100 is not significantly changed, there is no burden on the user's wrist. When a light source is provided at the lower part of the key switch device 100, the distance to the key top 1 is maintained, so light attenuation can be suppressed.

[0052] It is conceivable to overall lower the height of the key switch device in Patent Document 1 and provide a protrusion for mounting the key top on the slider. However, in this case, the key stroke becomes short and the operability deteriorates. Also, since it is necessary to reduce the size of the dome rubber, a good feel cannot be obtained. Furthermore, since the ceiling of the slider is covered, light is blocked and the key top cannot be sufficiently illuminated.

[0053] On the other hand, in the key switch device 100 of the first embodiment, a configuration of overall lowering the height of the key switch device and providing a protrusion on the slider on which the key top can be mounted is not adopted, so a sufficient key stroke can be ensured. Also, since it is not necessary to change the size of the dome rubber 3, a good feel can be obtained. Furthermore, since a path for guiding light, such as the gap between the through-hole 22a and the guide 52 and the slit 53, is formed, the light from the light source can be guided to the key top 1 and the key top 1 can be illuminated.

[0054] [Second Embodiment] The second embodiment is different from the first embodiment in the structures of the slider and the housing. FIG. 8(A) is an exploded perspective view showing the components of the switch unit included in the key switch device according to the second embodiment, and FIG. 8(B) is a perspective view of the integrated switch unit.

[0055] The switch unit 200 in FIG. 8(A) includes a slider 120 (sliding member) that slides in the vertical direction and is capable of mounting a key top 110 (see FIGS. 9(A) to 9(D)), a dome rubber 130 (first elastic member) that elastically buckles and deforms by pressing the key top 110 and applies a repulsive force corresponding to the elastic buckling deformation to the slider 120, a spring 140 (second elastic member) that is mounted on the slider 2 and presses an electrical contact such as a membrane switch or a mechanical switch (not shown), and a housing 150 (support member) to which the slider 120 is attached and that supports the vertical sliding of the slider 120.

[0056] In the switch unit 200, the spring 140 is fixed inside the support column portion 122 of the slider 120, the dome rubber 130 is sandwiched between the slider 120 and the housing 150, and the slider 120 is engaged with the housing 150 so that the slider 120 can slide vertically. As a result, as shown in FIG. 8(B), the slider 120, the dome rubber 130, the spring 140, and the housing 150 included in the switch unit 200 are integrated.

[0057] The dome rubber 130 is a dome-shaped member integrally formed from a rubber material, and has a ring-shaped base portion 131, a dome portion 132 that rises in a dome shape from the base portion 131, and a cylindrical portion 133 that extends upward from the top of the dome portion 132. The cylindrical portion 133 is press-fitted into the outer peripheral surface 123 of the slider 120 from below and is mounted on the outer peripheral surface 123. The dome portion 132 of the dome rubber 130 deforms according to the vertical sliding of the slider 120.

[0058] FIG. 9(A) is a plan view showing the front side of the key top 110, FIG. 9(B) is a cross-sectional view taken along line A-A of FIG. 9(A), FIG. 9(C) is a cross-sectional view taken along line B-B of FIG. 9(A), and FIG. 9(D) is a plan view showing the back side of the key top 110.

[0059] The key top 110 is integrally formed by using resin as a constituent material. As shown in FIGS. 9(B) to 9(D), a protrusion 112 protruding downward from the upper surface 113 of the key top 110 is provided on the back surface of the key top 110. A recess 111 for attaching to the cross-shaped protrusion 126 of the slider 120 (see FIGS. 8(A) and 8(B) and FIGS. 10(A) to 10(D)) is formed in the protrusion 112. The structure of the key top 110 is the same as the structure of the key top 1 in the first embodiment.

[0060] FIG. 10(A) is a plan view of the slider 120 viewed from above, FIG. 10(B) is a cross-sectional view taken along line A-A of FIG. 10(A), FIG. 10(C) is a cross-sectional view taken along line B-B of FIG. 10(A), and FIG. 10(D) is a perspective view of the slider 120.

[0061] The slider 120 has a main body portion 121 and a support portion 122 extending from the main body portion 121 toward the housing 150. The support portion 122 in the second embodiment is formed so that its cross-sectional shape is substantially square. The support portion 122 has a locking claw 125 for slidably locking the slider 120 to the housing 150. The locking claw 125 engages with a step 152a (see FIGS. 11(B) and 11(C)) on the inner wall of the guide 152 of the housing 150. An outer peripheral surface 123 is provided on the outer periphery of the main body portion 121, into which a protrusion 124 for engaging with the key top 110 and a dome rubber 3 are press-fitted. Also, a space 221 for the guide 152 of the housing 150 to enter is provided between the main body portion 121 and the support portion 122.

[0062] The ceiling portion 128, which is the upper end of the slider 120, includes a recess 127 for accommodating a protrusion 112 having a cross-shaped depression 111 of the key top 110, and a cross-shaped protrusion 126 for fitting into the cross-shaped depression 111 of the key top 110. The depth of the recess 127 is the same as the height of the protrusion 112 of the key top 110 or greater than the height of the protrusion 112. Thereby, even if a cross-shaped protrusion 126 is provided at the upper end of the slider 120, it is possible to suppress an increase in the overall height of the key switch device.

[0063] The support column portion 122 has an opening 222 formed therein downward, and a protrusion 223 for fixing a spring 140 is formed inside the support column portion 122. A part of the spring 140 is inserted and fixed between the inner side surface 224 of the support column portion 122 and the protrusion 223.

[0064] The slider 120 and the housing 150 are formed of different materials with little friction when they come into contact. For example, the slider 120 is formed of POM resin (polyacetal resin), and the housing 150 is formed of ABS resin (a thermoplastic resin made by polymerizing three monomers: acrylonitrile, butadiene, and styrene). This is because if the slider 120 and the housing 150 are formed of the same material, the slider 120 bites into the guide 152 during sliding, and a stack occurs where the key top 110 cannot move. Therefore, the slider 120 and the housing 150 are formed of different materials with little friction when they come into contact. Note that the materials of the slider 120 and the housing 150 are not limited to resins. Processing may be performed to reduce the friction coefficient at the contacting portions of the slider 120 and the housing 150 so that the friction is small when they come into contact.

[0065] FIG. 11(A) is a plan view of the housing 150 as viewed from above, FIG. 11(B) is a cross-sectional view taken along line A-A of FIG. 11(A), FIG. 11(C) is a cross-sectional view taken along line B-B of FIG. 11(A), and FIG. 11(D) is a perspective view of the housing 150.

[0066] The housing 150 is a member that supports the slider 120 and the dome rubber 130, and includes a square plate portion 151 that constitutes a base substrate. Further, the housing 150 has a guide 152 (first guiding portion) that stands upright upward from the center of the surface 151a of the plate portion 151 and guides the dome rubber 130, and a protrusion 153 (second guiding portion) that stands on the surface 151a of the plate portion 151 and is provided outside the guide 152 when the plate portion 151 is viewed from above to guide the dome rubber 130, and legs 156 that stand on the back surface 151b of the plate portion 151 and can be attached to an opening 161 (see FIGS. 12(B) and (C)) of a switch panel 160 (member to be attached). Further, the legs 156 include claw portions 157 that sandwich the switch panel 160 between the legs 156 and the back surface 151b of the plate portion 151. Since the legs 156 alone may be sufficient to fix the switch panel 160, the legs 156 do not necessarily have to include the claw portions 157. An opening 251 is formed at the position of the plate portion 151 above the claw portions 157. Thereby, the user can confirm from above whether the switch panel 160 is sandwiched between the claw portions 157 and the back surface 151b of the plate portion 151. Note that the number of the claw portions 157 is not limited to two and may be four.

[0067] A through-hole 250 having a substantially rectangular cross-section for inserting the support column portion 122 of the slider 120 is opened at the center of the guide 152.

[0068] FIG. 12(A) is a plan view of a key switch device according to a second embodiment as viewed from above, FIG. 12(B) is a cross-sectional view taken along line A-A of FIG. 12(A), and FIG. 12(C) is a cross-sectional view taken along line B-B of FIG. 12(A). FIG. 13 is a diagram showing an example in which a plurality of key switch devices are arranged.

[0069] The key switch device 300 according to the second embodiment includes a switch unit 200 including a slider 120, a dome rubber 130, a spring 140, and a housing 150, a key top 110 that is attached to the switch unit 200 and is pressed downward, a switch panel 160 that is a positioning member for determining the position of the housing 150, a membrane switch 170 that is disposed below the housing 150 and the switch panel 160 and has electrical contacts, and a support panel 180 that is disposed below the membrane switch 170 and fixes the switch panel 160.

[0070] The membrane switch 170 includes electrical contacts 171. The electrical contacts 171 are disposed below the housing 150 and the switch panel 160, and are closed when a predetermined pressing force acts from the spring 140 due to the pressing of the key top 110. In the second embodiment, the membrane switch 170 is used, but it is not particularly limited as long as it is a switch having electrical contacts. For example, a mechanical switch may be employed instead of the membrane switch 170.

[0071] The switch panel 160 is disposed on the membrane switch 170 and the support panel 180, and is fixed to the support panel 180 by a screw or the like (not shown) to a spacer 162 provided below the switch panel 160. The shape of the opening 161 of the switch panel 160 is square in plan view, and when the leg portion 156 of the housing 150 is attached to the opening 161, the opening 161 is covered by the plate portion 151 of the housing 150. A space 190 having a predetermined height is formed between the switch panel 160, the membrane switch 170, and the support panel 180 by the spacer 162.

[0072] If a predetermined space 190 is formed by the height of the leg portion 156, the key switch device 300 can be configured without providing the switch panel 160 by attaching the lower portion of the housing 150 to the upper surface of the membrane switch 170 with double-sided tape or the like.

[0073] When the user presses the key top 110, the column portion 122 of the slider 120 slides with respect to the through hole 250 of the guide 152, and the slider 120 moves downward. Due to the movement of the slider 120, the dome rubber 130 deforms outward. Due to the movement of the slider 120, the spring 140 attached to the slider 120 contacts the membrane switch 170, and as the spring 140 contracts, it presses the membrane switch 170, and the electrical contact 171 is connected.

[0074] When the user releases the finger from the key top 110, due to the elastic forces of the dome rubber 130 and the spring 140, the slider 120 returns to its original position. In the membrane switch 170, the pressing force of the key top 110 decreases and the electrical contact 171 is opened. The depression characteristics of the key switch device 300 are the same as those of the key switch device 100 in FIG. 6.

[0075] The key switch device 300 is disposed, for example, on a keyboard. The keyboard 201 may be created by changing a number of the key switch devices 100 in FIG. 7 to a number of the key switch devices 300.

[0076] In the switch unit 200, in a plan view, the area of the plate portion 151 is larger than the area of the opening 161 of the switch panel 160. For this reason, the plate portion 151 of the housing 150 contacts the peripheral portion of the opening 161 of the switch panel 160, and the leg portion 156 of the housing 150 can be attached to the opening 161 of the switch panel 160. It is possible to prevent the entire housing 150 from sinking into the opening 161 of the switch panel 160.

[0077] When the diameter of the base portion 131 of the dome rubber 130 is larger than the length of one side of the plate portion 151 of the housing 150, the base portion 131 of the dome rubber 130 protrudes from the plate portion 151 of the housing 150, making it difficult to obtain the pressing-down characteristics of the key switch device in FIG. 6. When the diameter of the base portion 131 of the dome rubber 130 is smaller than 70% of the length of one side of the plate portion 151 of the housing 150, the size of the dome rubber 130 becomes small, making it difficult to obtain the pressing-down characteristics of the key switch device in FIG. 6. For this reason, it is preferable that the diameter of the base portion 131 of the dome rubber 130 is 70% or more and 100% or less of the length of one side of the plate portion 151 of the housing 150. In particular, by setting the diameter of the base portion 131 of the dome rubber 130 and the length of one side of the plate portion 151 of the housing 150 to the same length, the size of the dome rubber 130 becomes large, so that the pressing-down characteristics of the key switch device in FIG. 6 are easily obtained and the housing 150 can hold the dome rubber 130.

[0078] In the conventional key switch device, since the housing is inserted from below the support panel, a flange for preventing detachment is required for the housing, and the lower part of the housing disposed below the support panel becomes large. For this reason, as shown in FIG. 13, it was difficult to set the center-to-center distance between two adjacent key tops 110 to 19 mm using a dome rubber 130 having a diameter of 18 mm.

[0079] In the second embodiment, as shown in FIG. 13, the center-to-center distance between two adjacent key tops 110 is 19 mm. For example, when the opening 161 is set to a square of 15 to 16 mm, the plate portion 151 of the housing 150 can be made into a square of 18 mm and the diameter of the base portion 131 of the dome rubber 130 can be made 18 mm. Also, the interval between the plate portions 151 of two adjacent housings 150 can be set to 1 mm. Note that the sizes of the opening 161, the plate portion 151, and the dome rubber 130 are merely examples, and the sizes of the opening 161, the plate portion 151, and the dome rubber 130 can be adjusted as long as adjacent keys do not interfere with each other.

[0080] As described above, according to the second embodiment, the switch unit 200 can be attached with the key top 110, and includes a slider 120 that is slidable by pressing the key top 110, a dome rubber 130 that is attached to the slider 120 and elastically deforms according to the pressing operation of the key top 110, a spring 140 that is attached to the slider 120 and opens and closes the electrical contact 171 according to the sliding of the slider 120, a plate portion 151 having a front surface 151a and a back surface 151b, a guide 152 that is erected on the front surface 151a and guides the slider 120, a protrusion 153 that is erected on the front surface 151a and is provided outside the guide 152 when the plate portion 151 is viewed from above to guide the dome rubber 130, and a leg portion 156 that is erected on the back surface 151b and can be attached to the opening 161 of the switch panel 160. And, in a plan view, the area of the plate portion 151 is larger than the area of the opening 161 of the switch panel 160. Therefore, by simply inserting the leg portion 156 of the housing 150 into the opening 161 of the switch panel 160, the slider 120, the dome rubber 130, the spring 140 and the housing 150 can be attached to the switch panel 160 together without separating them.

[0081] Further, the slider 120, the dome rubber 130, the spring 140 and the housing 150 integrally form the switch unit 200, and by inserting the leg portion 156 of the housing 150 into the opening 161 of the switch panel 160, the switch unit 200 is fixed to the opening of the switch panel 160 from above. Thereby, by simply inserting the leg portion 156 of the housing 150 into the opening 161 of the switch panel 160, the user can easily attach the switch unit 200 with the desired pressing characteristics to the switch panel 160. Also, the user can replace the switch unit 200 attached to the switch panel 160 for each switch unit.

[0082] In a conventional key switch device, a slider and a dome rubber with a spring attached to the front surface side of the switch panel are arranged, a housing is arranged on the back surface side of the switch panel, and the switch panel is sandwiched between the slider and the dome rubber and the housing. It is necessary to separately attach the slider and the dome rubber with the spring and the housing to the switch panel, and the attachment work to the switch panel is complicated. On the other hand, the switch unit 200 in the present embodiment can integrally attach the slider 120, the dome rubber 130, the spring 140, and the housing 150 to the switch panel 160 from above, so that the attachment work to the switch panel 160 can be easily performed.

[0083] In the second embodiment, since the key top 110 is replaceable and the key top 110 is inserted and removed, when the key top 110 is pulled out, the switch unit 200 may be pulled out from the switch panel 160. For this reason, it is preferable that the leg portion 156 includes a claw portion 157 that sandwiches the switch panel 160 between the back surface 151b of the plate portion 151. Thereby, the claw portion 157 comes into contact with the switch panel 160, and it is possible to prevent the switch unit 200 from being pulled out from the switch panel 160 from above.

[0084] Since the ceiling portion 128, which is the upper end of the slider 120, includes a recess 127 that houses a protrusion 112 having a depression 111 of the key top 110 and a protrusion 126 for fitting into the depression 111 of the key top 110, even if the protrusion 126 is provided at the upper end of the slider 120, it is possible to suppress an increase in the overall height of the key switch device 300.

[0085] Note that the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the gist of the invention.

Description of Reference Numerals

[0086] 1,110 Key top, 2,120 Slider, 3,130 Dome rubber, 4,140 Spring, 5,150 Housing, 6,160 Switch panel, 7,170 Membrane switch, 8,180 Support panel, 21 Protrusion, 22 Pedestal part, 22a, 54, 56 Through hole, 22b Connecting part, 23 Support column part, 51 Plate part, 52 Guide, 53 Slit, 55 Groove part, 100 Key switch device, 101,200 Switch unit, 201 Keyboard

Claims

1. A switch unit having a slidable member that can be attached with an operating member and is slidable by a pressing operation of the operating member, and a support member that supports the slidable member, and opening and closing an electrical contact according to the sliding of the slidable member, wherein the slidable member includes a pedestal portion, a first protrusion provided on the pressing operation side along the sliding direction of the slidable member from the pedestal portion and capable of attaching the operating member, and a support column portion provided on the side opposite to the pressing operation side along the sliding direction from the pedestal portion, the support member includes a plate portion and a first guide portion provided on the pressing operation side from the plate portion along the sliding direction, the pedestal portion has a first through hole through which the first guide portion passes, and the first guide portion has a second through hole into which the support column portion is inserted, characterized in that it is a switch unit.

2. When the operating member is pressed and located at the lowermost position, the upper end of the slidable member is at substantially the same height as the upper end of the first guide portion or is located below the upper end of the first guide portion, characterized in that it is the switch unit according to claim 1.

3. A first elastic member attached to the slidable member and elastically deformed according to the pressing operation of the operating member, and a second elastic member attached to the slidable member and opening and closing an electrical contact according to the sliding of the slidable member, characterized in that it is the switch unit according to claim 1.

4. The pedestal portion has a cylindrical shape and includes a connecting portion connecting the side surface thereof and the support column portion, and the first guide portion includes a slit for avoiding interference with the connecting portion, wherein the length of the slit in the sliding direction is substantially the same as the thickness of the support column portion in the sliding direction, characterized in that it is the switch unit according to claim 1.

5. A part of the outer periphery of the lower surface of the pedestal portion is formed with an extension portion extending along the support column portion, a second protrusion protruding radially inward is formed at the lower portion of the extension portion, a groove portion that engages with the second protrusion and extends along the sliding direction is formed in the first guide portion of the support member, characterized in that it is the switch unit according to claim 1.

6. The length of the extension portion in the sliding direction is set such that when the operating member is not pressed, the position of the upper surface of the pedestal portion is substantially the same as the position of the upper end of the first guide portion in a state where the second protrusion engages with the groove portion, characterized in that it is the switch unit according to claim 5.

7. The switch unit according to claim 1, wherein the plate portion is provided with a third through hole for arranging a light source.

8. A key switch device comprising the switch unit according to any one of claims 1 to 7, on which the operation member is mounted, and an electrical contact disposed under the switch unit, wherein the electrical contact is opened and closed by a pressing operation of the operation member.

9. A keyboard characterized in that a plurality of the key switch devices according to claim 8 are arranged.

10. A slidable member that can be mounted with an operation member and is slidable by a pressing operation of the operation member, A first elastic member mounted on the slidable member and elastically deformed in response to a pressing operation of the operation member, A second elastic member mounted on the slidable member and opening and closing an electrical contact in response to the sliding of the slidable member, A plate portion having a first surface and a second surface on the opposite side of the first surface, a first guide portion erected on the first surface of the plate portion for guiding the slidable member, and a second guide portion erected on the first surface of the plate portion and provided outside the first guide portion when the plate portion is viewed from above for guiding the first elastic member, and a leg portion erected on the second surface of the plate portion, and a support member having the same. A switch unit characterized by comprising the same.

11. The switch unit according to claim 10, wherein the leg portion is provided with a claw portion for fixing the leg portion to a member to be mounted.

12. The slidable member includes a pedestal portion, a first protrusion provided on the pressing operation side along the sliding direction of the slidable member from the pedestal portion and capable of mounting the operation member, and a support column portion provided on the side opposite to the pressing operation side along the sliding direction from the pedestal portion. The switch unit according to claim 10, wherein the pedestal portion has a first through hole passing through the first guide portion, and the first guide portion has a second through hole into which the support column portion is inserted.

13. The switch unit according to claim 10, wherein a ceiling portion of the slidable member includes a concave portion for accommodating a protrusion having a depression of the operation member, and a protrusion for fitting into the depression of the operation member.

14. A key switch device comprising the switch unit according to any one of claims 10 to 13, on which the operation member is mounted, a member to be mounted having an opening for mounting the leg portion of the switch unit, and an electrical contact disposed under the switch unit.

15. A switch unit according to any one of claims 10 to 13, to which the operation member is attached, and a membrane switch having electrical contacts, wherein the support member is attached to the membrane switch, a key switch device.

16. A keyboard, characterized in that a plurality of key switch devices according to claim 14 are arranged.

17. A keyboard, characterized in that a plurality of key switch devices according to claim 15 are arranged.

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