JP2016091928A - Key switch structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a key switch structure capable of implementing excellent contact opening/closing regardless of a position where an operation part is pressed.SOLUTION: Between an operation part 24B and a metal dome 16, a pressing plate part 22B is disposed of which the flexure rigidity is higher than that of the operation part 24B, and one side of the pressing plate part 22B is supported at one end side and the other end side by a main body portion 22A in a tiltable manner via a first hinge part 22Ca and a second hinge part 22Cb. Since the pressing plate part 22B is tilted with a pair of the first hinge part 22Ca and the second hinge part 22Cb as a fulcrum while suppressing flexure deformation regardless of a pressing portion of the operation part 24B, the metal dome 16 is pressed in a central portion by the pressing plate 22B, buckled and deformed and a contact part 26 can be pressed with the central portion.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a key switch structure, and relates to a key switch structure used for an operation unit of an information processing device, a measuring device, a medical device, a personal computer, or the like.

As a key switch structure used in a conventional flat keyboard, for example, a key switch structure having a structure disclosed in Patent Documents 1 to 3 is known.
In this type of key switch structure, a base plate, a contact sheet, a metal elastic member formed in a spherical shape called a metal dome, a surface sheet provided with an operation unit (also called a key top), and the like are sequentially laminated. When the operation part is pressed, the metal dome arranged immediately below is pressed to cause buckling deformation, and as a result, the center part of the metal dome presses the contact part of the contact sheet and the contact part is energized. ing.

JP 2007-109486 A JP 2011-171267 A JP 2011-253504 A

  However, when the position pressed by the operator deviates from the center of the operation portion, the metal dome is difficult to buckle, and the center portion of the metal dome may not be able to press the contact portion of the contact sheet, so there is room for improvement.

  In view of the above facts, an object of the present invention is to provide a key switch structure capable of realizing good contact opening and closing regardless of the position where the operation unit is pressed.

  The key switch structure according to claim 1 is disposed at a position facing the contact portion, with a contact sheet having a contact portion that conducts by receiving a pressing force, and is convex in a direction opposite to the contact portion. An elastically deformable dome-shaped elastic member formed on the elastic member, an operation unit disposed on the elastic member and applying a pressing force toward the elastic member, and disposed between the elastic member and the operation unit And an integrated support plate formed of an elastically deformable material, wherein the integrated support plate has a slit formed in the periphery facing the elastic member, and the first hinge portion and the second hinge portion And a pressing plate portion that tilts toward the elastic member side is formed, the pressing plate portion is set to have higher bending rigidity than the operation portion, and the first hinge portion is formed on one side of the pressing plate portion. At one end, the second hinge Parts is disposed on the other end of said one side of the pressing plate portion.

  In the key switch structure according to claim 1, when the operating portion is pressed against the urging force of the elastic member, the dome-shaped elastic member is buckled and deformed, and the pressing force from the operating portion is changed to the pressing plate portion and the elastic member. It is transmitted to the contact portion through the member to make the contact portion conductive.

  Between the operating portion and the elastic member, a pressing plate portion of an integrated support plate having higher bending rigidity than the operating portion is arranged, and the pressing plate portion is provided on one end side and the other end side of one side. It is tiltably supported by the integrated support plate via the first hinge part and the second hinge part.

  For this reason, when the operating unit is pressed, the pressing plate unit is integrated with the pair of first hinge unit and second hinge unit as fulcrums while suppressing bending deformation regardless of the pressed part of the operating unit. Tilt without twisting relative to the support plate. For this reason, the elastic member can be buckled and deformed by pressing the central portion of the dome-shaped elastic member with the pressing plate portion that tilts with the first hinge portion and the second hinge portion as fulcrums.

  According to a second aspect of the present invention, in the key switch structure according to the first aspect, a surface sheet is provided which covers the whole of the integrated support plate and is made of a material having lower rigidity than the integrated support plate. The operation portion is formed on the sheet.

  In the key switch structure according to claim 2, since the operation portion is formed on the surface sheet covering the whole of the integrated support plate, the dust is interposed through the gap (between the main body portion and the pressing plate portion) of the integrated support plate. And the like can be prevented from entering the contact sheet side. Further, the number of parts can be reduced as compared with the case where a plurality of operation units are provided by a keyboard or the like and the operation units are individually attached to the respective pressing plate units.

  According to a third aspect of the present invention, in the key switch structure according to the first or second aspect, the integrated support plate is formed of a single synthetic resin plate on which a plurality of operation portions are formed.

  In the key switch structure according to the third aspect, since the integral support plate is formed of one synthetic resin plate on which a plurality of operation portions are formed, the configuration is simplified. In addition, the pressing plate portion, the first hinge portion, and the second hinge portion can be easily formed by punching out one synthetic resin plate.

  According to a fourth aspect of the present invention, in the key switch structure according to any one of the first to third aspects, the central portion of the elastic member and the pressing plate are in a state before the operating portion is pressed. The part is in contact.

  In the key switch structure according to claim 4, since the central portion of the elastic member and the pressing plate portion are in contact with each other before the operating portion is pressed, the pressing portion is tilted by pressing the operating portion. At this time, the central portion of the elastic member can be reliably pressed by the pressing plate portion. Thereby, the elastic member made into the dome shape can be effectively buckled and deformed.

  According to a fifth aspect of the present invention, in the key switch structure according to any one of the first to fourth aspects, the pressing plate portion is provided with a protrusion that presses a central portion of the elastic member. Yes.

  In the key switch structure according to claim 5, since the pressing plate portion is provided with a protrusion for pressing the central portion of the elastic member, when the operating portion is pressed and the pressing plate portion tilts, the pressing plate portion The central portion of the elastic member can be reliably pressed by the protrusion. Since the projection of the pressing plate portion presses the central portion of the elastic member having the dome shape, the elastic member having the dome shape can be buckled and deformed effectively and reliably.

  According to a sixth aspect of the present invention, in the key switch structure according to the fifth aspect, the protrusion is formed by deforming a part of the pressing plate portion into a convex shape.

  In the key switch structure according to claim 6, since the protrusion of the pressing plate portion is formed by deforming a part of the pressing plate portion into a convex shape, when attaching a protrusion of another member to the pressing plate portion In comparison, the manufacturing is easy and the number of parts can be reduced.

  Since the key switch structure of the present invention has the above-described configuration, it has an excellent effect that a good contact opening / closing can be realized regardless of the position where the operation unit is pressed.

It is a disassembled perspective view which shows the key switch structure which concerns on the 1st Embodiment of this invention. (A) is a longitudinal cross-sectional view showing the key switch structure according to the first embodiment in a state where the operation unit is not pressed, and (B) is a first state in which the central part of the operation unit is slightly pressed. It is a longitudinal cross-sectional view which shows the key switch structure which concerns on embodiment, (C) is a longitudinal cross-section which shows the key switch structure which concerns on 1st Embodiment of the state by which the center part of the operation part was pushed down and the contact part was pressed It is a figure and (D) is the longitudinal cross-sectional view which looked at the key switch structure shown to (C) from the arrow R direction. (A) is a top view which shows a part of integral support plate, (B) is a top view which shows a part of integral support plate which concerns on a modification. (A) is a longitudinal cross-sectional view showing the key switch structure according to the first embodiment in a state where the operation unit is not pressed, and (B) is the first state in which the end of the operation unit is slightly pressed. It is a longitudinal cross-sectional view which shows the key switch structure which concerns on embodiment, (C) is a longitudinal cross-section which shows the key switch structure which concerns on 1st Embodiment of the state by which the edge part of the operation part was pushed down and the contact part was pressed It is a figure and (D) is the longitudinal cross-sectional view which looked at the key switch structure shown to (C) from the arrow R direction. (A) is a longitudinal cross-sectional view which shows the key switch structure which concerns on the comparative example of the state in which the operation part is not pressed down, (B) is the key switch which concerns on the comparative example of the state by which the edge part of the operation part was pushed down for a while It is a longitudinal cross-sectional view which shows a structure, (C) is a longitudinal cross-sectional view which shows the key switch structure which concerns on the comparative example of the state by which the center part of the operation part was pushed down and the contact part was pressed, (D) is operation It is a longitudinal cross-sectional view of the key switch structure which concerns on the comparative example which pressed down the edge part of the part. It is a top view which shows a part of integral support plate of the key switch structure which concerns on 2nd Embodiment. (A) is a longitudinal cross-sectional view showing the key switch structure according to the second embodiment in a state where the operation unit is not pressed, and (B) is a second state in which the central part of the operation unit is slightly pressed. It is a longitudinal cross-sectional view which shows the key switch structure which concerns on embodiment, (C) is a longitudinal cross-section which shows the key switch structure which concerns on 2nd Embodiment of the state by which the center part of the operation part was pushed down and the contact part was pressed It is a figure and (D) is the longitudinal cross-sectional view which looked at the key switch structure shown to (C) from the arrow R direction. It is a longitudinal cross-sectional view which shows the key switch structure which concerns on the modification of the key switch structure which concerns on 2nd Embodiment. It is a disassembled perspective view which shows the key switch structure which concerns on the 3rd Embodiment of this invention. It is a perspective view which shows the support plate and operation part of a key switch structure which concern on the 3rd Embodiment of this invention. (A) is a longitudinal cross-sectional view showing the key switch structure according to the third embodiment in a state where the operation unit is not pressed, and (B) is a third state in which the central part of the operation unit is slightly pressed. It is a longitudinal cross-sectional view which shows the key switch structure which concerns on embodiment, (C) is a longitudinal cross-section which shows the key switch structure which concerns on 3rd Embodiment of the state by which the center part of the operation part was pushed down and the contact part was pressed It is a figure and (D) is a longitudinal cross-sectional view which shows the key switch structure based on 3rd Embodiment in the state by which the edge part of the operation part was pressed down. It is a perspective view which shows a part of integral support plate of the key switch structure which concerns on other embodiment.

[First Embodiment]
Hereinafter, a first embodiment of a key switch structure 10 according to the present invention will be described with reference to the drawings. As shown in FIG. 1, the key switch structure 10 according to the present embodiment includes a base plate 12, a contact sheet 14, a plurality of metal domes 16, a fixing tape 18, a spacer 20, an integrated support plate 22, and a surface sheet 24. It is configured to include.

(Base plate)
The base plate 12 is a plate material made of synthetic resin or the like.
(Surface sheet)
The top sheet 24 is formed of a flexible synthetic resin material that can be elastically deformed. The thin sheet main body 24A and a plurality of operation units that are integrally formed to protrude from the upper surface of the sheet main body 24A and are provided with characters, symbols, and the like. 24B. The operation unit 24B is formed thicker than the sheet main body 24A. The operation unit 24B of the present embodiment is formed in a rectangular shape in plan view, but may have another shape.

(Contact sheet)
As shown in FIG. 2A, the contact sheet 14 includes a spacer sheet 14C sandwiched between two sheets on which a wiring pattern (not shown) is printed, that is, an upper sheet 14A and a lower sheet 14B. It is set as the structure bonded together. Each sheet is made of a flexible synthetic resin material. The contact sheet 14 is disposed on the base plate 12.

  The contact sheet 14 includes a contact portion 26 immediately below the central portion of the operation portion 24B. The contact portion 26 is provided with an upper surface conductive pattern 28 and a lower surface conductive pattern 30 that serve as electrical contacts at respective positions of the upper surface sheet 14A and the lower surface sheet 14B that are bonded with the spacer sheet 14C of the contact sheet 14 interposed therebetween. It has been. In the spacer sheet 14C, the spacer hole 32 is provided in the contact portion 26. When the operation portion 24B is not depressed, the spacer sheet 14C is normally electrically connected to the upper surface by the spacer hole 32 as shown in FIG. The pattern 28 and the lower conductive pattern 30 are opposed to each other with a gap therebetween.

  A dome-shaped (spherical) metal dome 16 formed of a thin metal material is disposed on the upper surface sheet 14A of the contact sheet 14 with the convex surface side facing the operation unit 24B side immediately below the operation unit 24B. Yes. The metal dome 16 is formed with a protrusion 16A for pressing the contact portion 26 at the central portion on the concave side (upper surface sheet 14A side).

  A fixing tape 18 is attached to the upper surface of the upper sheet 14A. A hole 34 having an inner diameter smaller than the outer diameter of the metal dome 16 is formed in the fixing tape 18. The outer peripheral portion of the metal dome 16 is fixed to the upper surface sheet 14 </ b> A by the vicinity of the periphery of the hole 34 of the fixing tape 18. The central portion of the metal dome 16 is exposed from the hole 34 of the fixing tape 18.

  The contact portion 26 of the contact sheet 14 is pressed in the thickness direction, and as shown in FIG. 2C, the upper surface sheet 14A is elastically deformed to cause the upper surface conductive pattern 28 of the upper surface sheet 14A and the lower surface conductive pattern 30 of the lower surface sheet 14B. Is contacted electrically, and the switch is closed (on). When the pressing is released, as shown in FIG. 2A, the upper surface sheet 14A is restored to the original shape, and the upper surface conductive pattern 28 of the upper surface sheet 14A and the lower surface conductive pattern 30 of the lower surface sheet 14B are separated from each other, The switch is opened (off).

(Integrated support plate)
The integrated support plate 22 is formed of a synthetic resin material plate having higher rigidity than the top sheet 24. As shown in FIG. 1, the integrated support plate 22 is formed in the same vertical and horizontal dimensions as the top sheet 24, and the operation unit 24 </ b> B indicated by a two-dot chain line as shown in FIG. 3 at a position facing the operation unit 24 </ b> B. A substantially rectangular opening 37 larger than that is formed. In the opening 37, there is disposed a substantially rectangular push-down plate portion 22B that is substantially similar to the operation portion 24B and is slightly smaller than the operation portion 24B.

  In the pressing plate portion 22B, the vicinity of one end of the one side 22Ba on the drawing arrow L direction side in the drawing arrow U direction side and the main body portion 22A of the integrated support plate 22 are connected via the first hinge portion 22Ca. The vicinity of one end on the drawing arrow U direction side of the other side 22Bb on the drawing arrow R direction side facing the side 22Ba and the main body portion 22A of the integrated support plate 22 are connected via a second hinge portion 22Cb.

  As shown in FIG. 2D, the push-down plate portion 22B can be inclined with respect to the main body portion 22A with the first hinge portion 22Ca and the second hinge portion 22Cb as fulcrums. The pressing plate portion 22B has higher bending rigidity than the operation portion 24B, and therefore the pressing plate portion 22B is less likely to bend and deform than the operation portion 24B.

  As shown in FIG. 3, the pressing plate portion 22B is arranged inside the opening 37, so that the integrated support plate 22 has the first slit 36 and the first slit 36 along the outer periphery of the operation portion 24B of the topsheet 24. Two slits 38 are formed. The first slit 36 is formed continuously along the three sides (22Ba, 22Bb, 22Bc) of the pressing plate portion 22B, and the second slit 38 is formed on the remaining side (22Bd) of the pressing plate portion 22B. Are formed along. The first hinge portion 22Ca is formed between the end of the first slit 36 on the arrow L direction side and the second slit 38, and the second hinge portion 22Cb is formed on the first slit 36. It is formed between the end on the arrow R direction side and the second slit 38. The integrated support plate 22 of the present embodiment is formed by forming the first slit 36 and the second slit 38 on a single synthetic resin plate by punching or the like, so that the pressing plate portion 22B and the first hinge The part 22Ca and the second hinge part 22Cb can be easily formed.

  In the integrated support plate 22 of the embodiment, as shown in FIG. 3A, the first hinge portion 22Ca is connected to the side 22Ba on the arrow L direction side of the pressing plate portion 22B, and the second hinge portion 22Cb is pressed. Although it is connected to the side 22Bb of the plate portion 22B in the direction of the arrow R, as shown in FIG. 3B, the direction of the push-down plate portion 22B is 90 degrees with respect to the push-down plate portion 22B shown in FIG. You can change it. The first hinge part 22Ca and the second hinge part 22Cb may be provided on both ends of either side of the push-down plate part 22B.

  The spacer 20 is disposed between the integrated support plate 22 and the fixing tape 18, and an opening 20A is formed so as not to interfere with the pressing plate portion 22B.

(Action)
In the key switch structure 10 of the present embodiment, when the center portion of the operation unit 24B is pushed down with a finger or the like (not shown) as shown by an arrow F in FIGS. 2 (B) and 2 (C), The pressing plate portion 22B arranged immediately below the operation portion 24B is tilted with the first hinge portion 22Ca and the second hinge portion 22Cb as fulcrums, and the tilted pressing plate portion 22B is the center of the metal dome 16, and Press around the center. When the push-down plate portion 22B is tilted, the first hinge portion 22Ca and the second hinge portion 22Cb are mainly twisted and deformed.

  When the operation load of the operation portion 24B is applied, the center portion of the metal dome 16 finally protrudes toward the contact portion 26 of the contact sheet 14 as shown in FIGS. 2 (C) and 2 (D). The metal dome 16 is buckled and the protrusion 16A provided at the center of the metal dome 16 presses the contact portion 26 of the contact sheet 14. As a result, the upper surface conductive pattern 28 of the contact sheet 14 and the lower surface conductive pattern 30 of the lower surface sheet 14B come into contact with each other and are electrically connected, and the switch is turned on.

  By the way, in the key switch structure 10 of this embodiment, as shown by the arrow F in FIG. 4, the end of the operation unit 24B may be pressed with a finger or the like (not shown). However, since the bending rigidity of the pressing plate portion 22B is higher than the bending rigidity of the operating portion 24B, the bending deformation of the pressing plate portion 22B is small as shown in FIGS. While maintaining the substantially flat plate shape, the first hinge portion 22Ca and the second hinge portion 22Cb are tilted about the fulcrum (see FIG. 4D). For this reason, the pressing plate portion 22B can reliably press the center portion of the metal dome 16 and the periphery of the center portion around the center portion and the center portion.

  Since the metal dome 16 is pressed at the central portion and the periphery of the central portion by the substantially flat plate-shaped pressing plate portion 22B, the metal dome 16 has a central portion as when the central portion of the operation portion 24B is pressed. The buckling deformation is caused to be convex toward the contact sheet 14, and the contact portion 26 of the contact sheet 14 can be surely pressed down by the protrusion 16A provided at the center.

  On the other hand, when the finger or the like is released from the operation unit 24B, the metal dome 16, the operation unit 24B, and the contact sheet 14 are elastically restored to their original shapes by their own restoring force, and the lower surface conductive patterns of the upper surface conductive pattern 28 and the lower surface sheet 14B. 30 is separated and the switch is opened.

  Below, the key switch structure 100 which concerns on the comparative example in which the integrated support plate 22 is not provided is demonstrated based on FIG. 5 (A)-(D). In addition, the same code | symbol is attached | subjected to the same structure as this embodiment, and the description is abbreviate | omitted. As shown in FIGS. 5A to 5C, in the key switch structure 100 according to the comparative example, when the center portion of the operation portion 24B is pressed, the center portion and the vicinity of the center of the metal dome 16 are the operation portion 24B. The metal dome 16 is buckled by being pressed, and the contact portion 26 of the contact sheet 14 is pushed down at the center of the metal dome 16.

  In the key switch structure 100 according to the comparative example, when the end of the operation unit 24B is pressed as shown in FIG. 5D, only the vicinity of the end of the operation unit 24B is deformed and only the vicinity of the outer periphery of the metal dome 16 is obtained. The metal dome 16 cannot be buckled and deformed, and the contact portion 26 cannot be pushed down by the metal dome 16 in some cases.

  On the other hand, in the key switch structure 10 of this embodiment, as shown in FIGS. 4C and 4D, even when the end of the operation unit 24B is pressed, the contact portion 26 can be pressed by the metal dome 16. Thus, unlike the key switch structure 100 according to the comparative example, it is difficult to cause an operation failure in which the contact portion 26 cannot be pressed down, and a favorable contact opening / closing can be realized.

  In the key switch structure 10 of the present embodiment, the pressing plate portion 22B is supported by the main body portion 22A with the two locations of the first hinge portion 22Ca and the second hinge portion 22Cb as fulcrums, and the pressing plate portion 22B. The bending rigidity is higher than that of the operation unit 24B. For this reason, no matter which part of the pressing plate portion 22B is pressed, the pressing plate portion 22B can be tilted without twisting with the two locations of the first hinge portion 22Ca and the second hinge portion 22Cb as fulcrums. The metal dome 16 can be reliably buckled and deformed by pressing the center portion and the vicinity of the center of the metal dome 16 at the center portion and the vicinity of the center of the pressing plate portion 22B.

  When the pressing plate portion 22B is supported by one of the first hinge portion 22Ca and the second hinge portion 22Cb, that is, the pressing plate portion 22B is supported at one place with respect to the main body portion 22A. In this case, depending on the part where the operation part 24B is pressed, the entire pressing plate part 22B is twisted with the supported part as a fulcrum. If the portion where the entire pressing plate portion 22B is supported is twisted as a fulcrum, the vicinity of the end of the metal dome 16 is pressed near the end of the pressing plate portion 22B, and the metal dome 16 can be buckled and deformed. However, in the key switch structure 10 of the present embodiment, the pressing plate portion 22B as a whole is not twisted regardless of which part of the operation portion 24B is pressed, and the metal dome 16 is securely attached. It can be buckled and deformed.

  Moreover, in the key switch structure 10 of this embodiment, since the integrated support plate 22 in which the 1st slit 36 and the 2nd slit 38 were formed is covered with the surface sheet 24, dust etc. are 1st slits. There is no risk of entering the space S (see FIG. 2) on the contact sheet 14 side where the metal dome 16 is disposed through the 36 and the second slit 38.

[Second Embodiment]
Next, a key switch structure 10 according to a second embodiment of the present invention will be described with reference to FIGS. In addition, the same code | symbol is attached | subjected to the same structure as 1st Embodiment, and the description is abbreviate | omitted. As shown in FIGS. 6 and 7, in the key switch structure 10 of the present embodiment, a cylindrical pressing protrusion 23 for pressing the center portion of the metal dome 16 is attached to the metal dome side of the pressing plate portion 22B. It has been. In the present embodiment, the pressing protrusion 23 is in contact with the center of the metal dome 16, but it may be slightly separated.

(Function)
In the present embodiment, a pressing projection 23 that presses the central portion of the metal dome 16 is formed on the pressing plate portion 22B, and the pressing projection 23 is in contact with the central portion of the metal dome 16, so that FIG. , (C), when the central portion of the operation portion 24B is pressed, the central portion of the metal dome 16 is pressed by the pressing protrusion 23. As a result, the metal dome 16 is buckled, and the contact portion 26 is pressed by the protrusion 16 </ b> A of the metal dome 16.

  Further, as shown in FIG. 7D, even when the end portion of the operation portion 24B is pressed, the pressing protrusion 23 of the pressing plate portion 22B presses the central portion of the metal dome 16, so that the protrusion 16A of the metal dome 16 Thus, the contact portion 26 can be surely pressed down.

  Therefore, also in the key switch structure 10 of the present embodiment, good contact opening / closing can be realized as in the first embodiment.

  In the key switch structure 10 of the present embodiment, since the pressing projection 23 that presses the center of the metal dome 16 is formed on the pressing plate portion 22B, compared to the case where the pressing projection 23 is not formed, The center part of the metal dome 16 can be easily pressed.

  In the key switch structure 10 according to the present embodiment, a cylindrical pressing protrusion 23 separate from the pressing plate portion 22B is attached to the pressing plate portion 22B in order to press the central portion of the metal dome 16. As shown in FIG. 8, a part of the pressing plate portion 22B is plastically deformed by a press or the like so as to protrude substantially hemispherically toward the contact portion 26, and the protruding portion 25 protruding approximately hemispherically is pressed down. Can be used instead of.

[Third Embodiment]
Next, a key switch structure 10 according to a third embodiment of the present invention will be described with reference to FIGS. In addition, the same code | symbol is attached | subjected to the same structure as embodiment mentioned above, and the description is abbreviate | omitted.

  As shown in FIG. 9, in the key switch structure 10 of the present embodiment, the top sheet 24 provided with the operation unit 24B provided in the first embodiment is not provided. As shown, the operation portion 24B is fixed to the pressing plate portion 22B of the integrated support plate 22 by adhesion, welding, or the like. The operation unit 24B may be integrally formed with the push-down plate unit 22B of the integrated support plate 22.

  As shown in FIGS. 9 and 11, a frame 42 having an opening 40 for exposing the operation portion 24 </ b> B is attached on the integrated support plate 22. As an example, the frame 42 is formed of a plate material made of a synthetic resin having rigidity higher than that of the operation unit 24B.

  In the key switch structure 10 of the present embodiment, when the center portion of the operation portion 24B is pressed as shown in FIGS. 11B and 11C, the pressing plate portion 22B of the integrated support plate 22 is the same as in the second embodiment. Is tilted, the central portion of the metal dome 16 is pressed by the pressing protrusion 23, and the contact portion 26 is reliably pressed by the protrusion 16 </ b> A of the metal dome 16.

  Further, as shown in FIG. 11D, even if the end of the operation portion 24B is pressed, the pressing plate portion 22B is tilted and the central portion of the metal dome 16 is pressed by the pressing protrusion 23. The contact portion 26 is surely pressed by the 16 protrusions 16A.

  Therefore, also in the key switch structure 10 of the present embodiment, good contact opening / closing can be realized as in the first embodiment.

[Other Embodiments]
As mentioned above, although the Example of this invention was described, it cannot be overemphasized that this invention is not limited to said Example at all, and can implement in a various aspect in the range which does not deviate from the summary of this invention.

  The first hinge portion 22Ca and the second hinge portion 22Cb can be formed as shown in FIG. 3, but as shown in FIG. 12, both end portions of the second slit 38 and the first slit It can also be formed between the side portions near the end portions of 36. In this case, the first hinge portion 22Ca and the second hinge portion 22Cb are mainly bent and deformed when the pressing plate portion 22B is tilted.

  In the top sheet 24 of the above embodiment, the operation unit 24B is integrally formed on the upper surface of the sheet main body 24A, but the operation unit 24B may have the same thickness as the sheet main body 24A. In this case, a rectangular frame or the like indicating the area of the operation unit 24B to be pressed is given to the top sheet 24 by printing or the like.

  Instead of the contact sheet 14 used in the above embodiment, a well-known printed circuit board (PCB) having a contact portion that connects a power source (plus) and a ground (minus) (not shown) may be used.

10 Key switch structure 14 Contact sheet 16 Metal dome (elastic member)
22 Integrated support plate 22A Main body portion 22B Pressing plate portion 22Ca First hinge portion 22Cb Second hinge portion 23 Protrusion 24 Surface sheet 24B Operation portion 25 Protruding portion (protrusion)
37 opening

Claims (6)

A contact sheet having a contact portion that conducts under pressure, and
An elastically deformable dome-shaped elastic member disposed in a position facing the contact portion and formed in a convex shape in a direction opposite to the contact portion;
An operation unit that is disposed on the elastic member and applies a pressing force toward the elastic member;
An integral support plate that is disposed between the elastic member and the operation portion and formed of an elastically deformable material;
With
The integrated support plate is formed with a pressing plate portion that is tilted toward the elastic member side by forming a slit around the elastic member and leaving the first hinge portion and the second hinge portion cut off,
The pressing plate portion is set to have higher bending rigidity than the operation portion,
The key switch structure, wherein the first hinge portion is disposed on one end side of one side of the pressing plate portion, and the second hinge portion is disposed on the other end side of the one side of the pressing plate portion. A surface sheet made of a material that covers the whole of the integrated support plate and has lower rigidity than the integrated support plate is provided,
The key switch structure according to claim 1, wherein the operation portion is formed on the top sheet. The key switch structure according to claim 1 or 2, wherein the integrated support plate is formed of a single synthetic resin plate on which a plurality of operation portions are formed. The key switch structure according to any one of claims 1 to 3, wherein a center portion of the elastic member and the pressing plate portion are in contact with each other before the operation portion is pressed. The key switch structure according to any one of claims 1 to 4, wherein the pressing plate portion is provided with a protrusion that presses a central portion of the elastic member. The key switch structure according to claim 5, wherein the protrusion is formed by deforming a part of the pressing plate portion into a convex shape.