Push switch

Abstract

A good operation touch feeling can be presented to an operator, and collision sound of a movable contact member can be suppressed. The push switch is provided with: a housing having a recessed portion with an upper opening and having a fixed contact inside the recessed portion; a dome-shaped movable contact member which is housed in the recess of the housing and is formed from a metal plate; and an operation member that presses the movable contact member and reverses the movable contact member, the movable contact member having, in plan view, a side cut shape in which both sides of the movable contact member are linearly cut with respect to a circular shape, and the movable contact member is configured so that the movable contact member is fixed to the circular shape when A is the diameter of the circular shape and B is the distance between a pair of linear portions formed by the cutting. The side cut ratio calculated by (B / A) * 100 is within the range of 40%-70%.

Description

Technical Field

[0001] The invention relates to a push switch. Background Art

[0002] Patent Document 1 listed below discloses a movable contact member for use in a switch device, which is a dome-shaped movable contact member having a pair of notches facing each other in a skirt portion.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2012-64401 Summary of the invention

[0006] Problems to be solved by the invention

[0007] However, in the prior art, the silencing of the collision sound when the movable contact part collides with the fixed part due to the reversal action has become a problem. In the prior art, the silencing of the collision sound can be achieved by suppressing the reversal speed of the movable contact part, but on the other hand, there is a risk that a good operating touch cannot be presented to the operator.

[0008] Means used to solve problems

[0009] A push switch according to one embodiment comprises: a housing having a recessed portion with an upper opening, wherein a fixed contact is provided inside the recessed portion; a dome-shaped movable contact member which is accommodated in the recessed portion of the housing and is formed of a metal plate; and an operating member which presses the movable contact member to cause the movable contact member to perform a reverse action, wherein the movable contact member has a side cut (Japanese: サイドカット) shape in which both sides of a circular shape are cut in a straight line shape when viewed from above, and when the diameter of the circular shape is set to A and the interval between a pair of straight line portions formed by cutting is set to B, the side cut ratio calculated by (B / A)×100 is in the range of 40% to 70%.

[0010] Effects of the Invention

[0011] According to the push switch of one embodiment, a good operation feeling can be presented to the operator, and the collision sound of the movable contact member can be suppressed. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 This is a perspective view of the appearance of a push switch according to one embodiment.

[0013] Figure 2 This is an exploded perspective view of a push switch according to an embodiment.

[0014] Figure 3This is a cross-sectional view of a push switch according to an embodiment.

[0015] Figure 4 It is a perspective view showing a metal inverted dome arranged in a recessed portion of a housing.

[0016] Figure 5 It is a plan view showing a metal inverted dome arranged in a recessed portion of a housing.

[0017] Figure 6 This is a graph showing the operation load characteristics of the push switch according to one embodiment and a conventional push switch.

[0018] Figure 7 This is a graph showing the relationship between the side cut ratio and the inversion speed of the metal inversion dome according to one embodiment.

[0019] Fig. 8A This is a graph showing the reversal speed of a metal reversal dome in a conventional push switch.

[0020] Figure 8B This is a graph showing the reversal speed of the metal reversal dome in the push switch according to one embodiment.

[0021] Fig. 9 This is a graph showing the relationship between the side cut ratio and the sound pressure of the metal inverted dome according to one embodiment.

[0022] Fig.10 This is a graph showing the relationship between the side cut ratio of the metal inverted dome and the height of the dome shape according to one embodiment.

[0023] Fig.11 It is a top view showing a modified example of the housing and the metal inverted dome.

[0024] Description of Reference Numerals

[0025] 100 push switch

[0026] 110, 110-2 housing

[0027] 110A Top surface

[0028] 110B concave part

[0029] 110BaInner wall

[0030] 110Bb gap

[0031] 112 Central fixed contact

[0032] 113 Peripheral fixed contacts

[0033] 120 Frame

[0034] 120A Opening

[0035] 120B hook

[0036] 130 core column (operating part)

[0037] 131 Operation Department

[0038] 132 Support

[0039] 133 Pressing part

[0040] 140, 140-2 Metal inverted dome (movable contact part)

[0041] 140A Top

[0042] 140B Narrow Width

[0043] 141 Curve

[0044] 142 Straight Line

[0045] 143 Notch

[0046] 150 Insulator (protective sheet) DETAILED DESCRIPTION

[0047] Hereinafter, an embodiment will be described with reference to the accompanying drawings. In addition, in the following description, for convenience, the Z-axis direction in the figure is set as the up-down direction, the Y-axis direction in the figure is set as the left-right direction, and the X-axis direction in the figure is set as the front-back direction. Among them, the positive direction of the Z-axis is set as the top, the positive direction of the Y-axis is set as the right, and the positive direction of the X-axis is set as the front.

[0048] (Overview of Push Switch 100)

[0049] Figure 1 FIG. 1 is a perspective view of the appearance of a push switch 100 according to an embodiment. Figure 1 As shown, the push switch 100 as a whole has a thin rectangular parallelepiped shape in the vertical direction (Z-axis direction), and has a substantially square shape when viewed from above. In addition, the upper surface 110A of the housing 110 of the push switch 100 is covered by the frame 120. The housing 110 accommodates a stem 130 and the like. An operating portion 131 protruding upward (in the positive direction of the Z-axis) is provided in the central portion of the stem 130.

[0050] The operating portion 131 of the stem 130 passes through the circular opening 120A formed in the frame 120, and protrudes upward (in the positive direction of the Z axis) from the frame 120. Thus, the push switch 100 can be operated by pressing the operating portion 131 of the stem 130 downward (in the negative direction of the Z axis), and the switch OFF state can be switched to the switch ON state by the pressing operation.

[0051] (Structure of Push Switch 100)

[0052] Figure 2 This is an exploded perspective view of the push switch 100 according to one embodiment. Figure 3 FIG. 1 is a cross-sectional view of a push switch 100 according to an embodiment. Figure 2 and Figure 3 As shown, the push switch 100 includes a housing 110 , a metal inverted dome 140 , an insulator 150 , an elastic member 160 , a stem 130 , and a frame 120 in order from the lower side (negative side of the Z axis) in the figure.

[0053] The housing 110 is a thin container-shaped component in the vertical direction (Z-axis direction). The housing 110 has a substantially square shape when viewed from above. The housing 110 has a recess 110B with an upper opening that is recessed downward from the upper surface 110A. A metal inverted dome 140 is accommodated inside the recess 110B. For example, the housing 110 is formed by insert molding using a relatively hard insulating raw material (such as a hard resin, etc.).

[0054] A central fixed contact 112 and a pair of left and right peripheral fixed contacts 113 are provided on the inner bottom surface of the recess 110B of the housing 110. The central fixed contact 112 is provided at the center of the inner bottom surface of the recess 110B. The pair of left and right peripheral fixed contacts 113 are provided at the left and right ends of the inner bottom surface of the recess 110B. Both the central fixed contact 112 and the peripheral fixed contacts 113 are formed using a conductive material (e.g., a metal material).

[0055] In addition, if Figure 4 As shown in FIG. 1 , the inner wall portion 110Ba of the recessed portion 110B of the housing 110 is provided substantially along the outer edge of the metal inverted dome 140. However, in the inner wall portion 110Ba of the recessed portion 110B of the housing 110, the portions respectively facing the pair of straight portions 142 of the metal inverted dome 140 are provided at positions farther away in the X-axis direction than the straight portions 142. Thus, in the recessed portion 110B of the housing 110, a gap portion 110Bb is formed between each of the pair of straight portions 142 of the metal inverted dome 140 and the inner wall portion 110Ba.

[0056] Thus, in the push switch 100 of the embodiment, each of the pair of straight portions 142 of the metal inverted dome 140 is not close to the inner wall portion 110Ba of the recess 110B of the housing 110. Therefore, the push switch 100 of the embodiment can suppress the restriction of the movable range of the insulator 150, and thus can suppress the influence on the operation feel.

[0057] The metal inverted dome 140 is an example of a "movable contact member". The metal inverted dome 140 is a thin plate-shaped member made of a metal plate, having a dome shape with a top 140A in the center and convex upward (in the positive direction of the Z axis). For example, the metal inverted dome 140 is formed into a dome shape by stamping a metal plate.

[0058] The metal inverted dome 140 is received in the recess 110B of the housing 110 and disposed on the inner bottom surface of the recess 110B. The metal inverted dome 140 is placed on the inner bottom surface of the recess 110B of the housing 110 so that the outer peripheral edge portion contacts each of the pair of peripheral fixed contacts 113 .

[0059] The metal inversion dome 140 is a so-called "inversion spring". When the pressing operation of the operating portion 131 of the stem 130 is performed, the top portion 140A is pressed downward by the pressing portion 133 of the stem 130. When the predetermined operating load is exceeded, the top portion 140A is elastically deformed suddenly into a concave shape (inversion action). As a result, the metal inversion dome 140 contacts the central fixed contact 112 at the inner side of the top portion 140A and is electrically connected to the central fixed contact 112. As a result, the metal inversion dome 140 can make the central fixed contact 112 and the peripheral fixed contacts 113 conduct to each other via the metal inversion dome 140. In addition, when the pressing operation of the operating portion 131 of the stem 130 is released, the metal inversion dome 140 returns to its original convex shape by elastic force.

[0060] The insulator 150 is an example of a "protective sheet" and is a thin sheet-like component disposed on the upper surface 110A of the housing 110. The insulator 150 is formed using a resin raw material such as PET. When viewed from above, the insulator 150 has a substantially square shape, similar to the housing 110. The insulator 150 is bonded to the upper surface 110A of the housing 110 by any bonding means (such as heat welding, laser welding, adhesive, etc.) while covering the upper surface 110A of the housing 110. The insulator 150 closes the upper opening of the recess 110B of the housing 110, thereby sealing the recess 110B.

[0061] The stem 130 is an example of an “operating member” and is pressed downward by an operator. For example, the stem 130 is formed using a relatively hard insulating material (such as hard resin). The stem 130 includes an operating portion 131 , a supporting portion 132 , and a pressing portion 133 .

[0062] The operating portion 131 is provided at the center of the stem 130 , has a cylindrical shape protruding upward from the support portion 132 , and is a portion that is pressed by an operator.

[0063] The support portion 132 is a horizontal flat plate-shaped portion provided around the operating portion 131. The support portion 132 is provided integrally with the operating portion 131, and supports the operating portion 131. The outer shape of the support portion 132 has a substantially square shape in a plan view.

[0064] The pressing portion 133 is a dome-shaped portion protruding downward from the center of the bottom surface of the stem 130. The pressing portion 133 moves downward to press the top 140A of the metal inverted dome 140 when the operation portion 131 of the stem 130 is pressed.

[0065] The stem 130 is disposed between the frame 120 and the insulator 150 in a state where the operation portion 131 passes through the opening 120A of the frame 120 and the top of the pressing portion 133 abuts against the top 140A of the metal inverted dome 140 via the insulator 150 .

[0066] The frame 120 is a metal, flat plate-shaped member and is fixedly attached to the upper surface 110A of the housing 110 while pressing the support portion 132 of the stem 130 from above, thereby supporting the stem 130 disposed above the insulator 150 .

[0067] For example, the frame 120 is formed by processing a metal plate using a processing method such as stamping. In a plan view, a circular opening 120A is formed in the center of the frame 120 for allowing the operating portion 131 of the stem 130 to protrude upward. In addition, hooks 120B hanging downward are respectively provided on a pair of left and right sides of the outer peripheral edge of the frame 120. The frame 120 is fixed to the housing 110 by the pair of hooks 120B respectively engaging with the side surface and the bottom surface of the housing 110.

[0068] (Action of Push Switch 100)

[0069] In the push switch 100 of one embodiment, when the operation part 131 of the stem 130 is not pressed, the metal inverted dome 140 is in an initial state of being convex upward. Therefore, the metal inverted dome 140 contacts the peripheral fixed contacts 113, but does not contact the central fixed contact 112. That is, the peripheral fixed contacts 113 and the central fixed contact 112 are not connected to each other. Therefore, the push switch 100 of one embodiment is in a switch-off state when the operation part 131 of the stem 130 is not pressed.

[0070] Furthermore, in the push switch 100 of the embodiment, when the operation portion 131 of the stem 130 is pressed, the pressing portion 133 of the stem 130 presses the top portion 140A of the metal inverted dome 140 , thereby elastically deforming the metal inverted dome 140 .

[0071] Furthermore, in the push switch 100 of one embodiment, when the operation load of the push operation of the operation portion 131 of the stem 130 exceeds a predetermined threshold value (that is, when the stroke of the stem 130 exceeds the top stroke amount), the top 140A of the metal inversion dome 140 is elastically deformed into a concave shape (inversion operation). As a result, the stroke of the stem 130 becomes the bottom stroke amount, and the inner side portion of the top 140A of the metal inversion dome 140 contacts the central fixed contact 112, thereby being electrically connected to the central fixed contact 112.

[0072] As a result, the push switch 100 of one embodiment is in a switch-on state by making the central fixed contact 112 and the peripheral fixed contact 113 conduct to each other via the metal inversion dome 140. At this time, the push switch 100 of one embodiment can provide a click feeling (Japanese: クリック

[0073] Therefore, the push switch 100 according to one embodiment can allow the operator to grasp the fact that the switch has been switched to the on state by tactile sensation.

[0074] In the push switch 100 of the embodiment, when the pressing operation by the pressing portion 133 of the stem 130 is released, the metal inverted dome 140to returns to its original convex shape by its own elastic force. As a result, the push switch 100 of the embodiment returns to the switch-off state.

[0075] (Shape of the metal inverted dome 140)

[0076] Figure 4 It is a perspective view showing a state where the metal inverted dome 140 is arranged in the recessed portion 110B of the housing 110 . Figure 5 It is a plan view showing the metal inverted dome 140 arranged in the recessed portion 110B of the housing 110 .

[0077] The metal inverted dome 140 has a side cut shape in which both sides of the circular shape C are cut in a straight line shape when viewed from above. Specifically, the metal inverted dome 140 has a pair of curved portions 141 along the circumference of the circular shape C and a pair of straight portions 142 parallel to each other. The circular shape C is a circle having a common center with the metal inverted dome 140 and a predetermined radius r.

[0078] In the metal inverted dome 140, a pair of curved portions 141 are provided at both ends in the left-right direction (Y-axis direction). The curved portion 141 on the left side (Y-axis negative side) is a curved portion with a curvature radius of radius r, and connects the left ends of the pair of straight portions 142. The curved portion 141 on the right side (Y-axis positive side) is a curved portion with a curvature radius of radius r, and connects the right ends of the pair of straight portions 142.

[0079] A pair of straight line portions 142 are provided at both ends in the front-rear direction (X-axis direction) of the metal inversion dome 140. The pair of straight line portions 142 extend straightly in the left-right direction (Y-axis direction).

[0080] For example, the metal inverted dome 140 is formed by cutting both sides (parts forming a pair of straight line portions 142 ) of a metal dome-shaped member having a circular shape with a radius r when viewed from above in a straight line, thereby forming a shape having a pair of curved portions 141 and a pair of straight line portions 142 .

[0081] Here, if Figure 5 As shown, the metal inverted dome 140 sets the diameter A and the interval B so that the side cut ratio calculated by (B / A)×100 is within the range of 40% to 70% when the diameter of the circular shape C (i.e., the distance between the pair of curved portions 141) is A and the interval between the pair of straight portions 142 is B. The above-mentioned range of the side cut ratio is a preferred range obtained by the applicant and others through simulations.

[0082] Therefore, the push switch 100 of one embodiment can present the same operating feel (i.e., good operating feel) to the operator compared to the previous push switch using a metal inversion dome that is circular when viewed from above (i.e., a metal inversion dome that is not side-cut), and can also reduce the reversal speed of the metal inversion dome 140 and suppress the collision sound (i.e., operating sound) between the metal inversion dome 140 and the central fixed contact 112.

[0083] The side cut ratio of the metal inverted dome 140 is more preferably in the range of 60% to 70%. This is because a higher side cut ratio is closer to a dome shape and can easily give the operator the same operating feel as a metal inverted dome without side cuts.

[0084] (Comparative example of operating load characteristics)

[0085] Figure 6 Graph showing the operation load characteristics of the push switch 100 according to one embodiment and a conventional push switch. Figure 6In the graph shown, the solid line shows the operation load characteristics of the push switch 100 according to one embodiment using the metal inverted dome 140 having an undercut shape, and the dotted line shows the operation load characteristics of the conventional push switch using a circular metal inverted dome.

[0086] like Figure 6 As shown, in the push switch 100 according to the embodiment, the amount of movement from the top load to the bottom load in the reversing operation of the metal reversal dome 140 is smaller than that of the conventional push switch.

[0087] In addition, if Figure 6 As shown, in the push switch 100 according to the embodiment, the amount of change in load from the top load to the bottom load during the reversing operation of the metal reversal dome 140 is smaller than that of the conventional push switch.

[0088] Therefore, the push switch 100 according to one embodiment can reduce the reversal speed of the metal reversal dome 140 compared to the conventional push switch, thereby suppressing the collision sound (ie, operation sound) between the metal reversal dome 140 and the center fixed contact 112 .

[0089] in addition, Figure 6 The triangular regions S1 and S2 shown contribute to the operational feel. The areas of the regions S1 and S2 represent the amount of the reverse movement of the metal inversion dome 140. When the amount of change in the operating load during the reverse movement of the metal inversion dome is C and the amount of change in the top of the metal inversion dome during the reverse movement is D, the areas of the regions S1 and S2 are calculated by C×D×1 / 2.

[0090] like Figure 6 As shown, the area of ​​region S2 of the push switch 100 of one embodiment is equal to the area of ​​region S1 of the conventional push switch. This means that the push switch 100 of one embodiment can present the same operation feeling (i.e., good operation feeling) to the operator compared with the conventional push switch.

[0091] In other words, in the push switch 100 according to one embodiment, the amount of the reverse movement of the metal inverted dome 140 can be said to be equal when the metal inverted dome 140 has an undercut shape and when the metal inverted dome 140 does not have an undercut shape.

[0092] (Relationship between the side cut ratio and the reversal speed of the metal reversal dome 140)

[0093] Figure 7 : This is a graph showing the relationship between the side cut ratio and the inversion speed of the metal inversion dome 140 according to one embodiment. Figure 7The graph shown shows the measurement results of the inversion speed of the metal inversion dome 140 when the side cut ratio of the metal inversion dome 140 is set to 40%, 50%, 60%, 70%, and 100%.

[0094] like Figure 7 As shown in FIG. 1 , it is found that the larger the side cut ratio of the metal inversion dome 140 is, the higher the inversion speed of the metal inversion dome 140 is. Figure 7 As shown, it was found that by setting the side cut ratio of the metal inverted dome 140 within the range of 40% to 70%, the inversion speed of the metal inverted dome 140 can be greatly reduced compared with the case where the side cut ratio of the metal inverted dome 140 is set to 100% (i.e., the case without a side cut shape).

[0095] (Comparative example of reverse speed)

[0096] Fig. 8A This is a graph showing the reversal speed of a metal reversal dome in a conventional push switch. Figure 8B : is a graph showing the reversal speed of the metal reversal dome 140 in the push switch 100 according to one embodiment. Fig. 8A and Figure 8B In the graph shown, the horizontal axis represents time [s], and the vertical axis represents the movement amount [mm] of the top of the metal inversion dome.

[0097] like Fig. 8A and Figure 8B As shown, in the push switch 100 of one embodiment, since the metal reversal dome 140 has a side cut shape, the amount of movement of the top of the metal reversal dome 140 is smaller and the time required for the reversal is longer when the metal reversal dome 140 is reversed compared to the conventional push switch. That is, in the push switch 100 of one embodiment, the reversal speed of the metal reversal dome 140 is lower than that of the conventional push switch.

[0098] Therefore, compared with the conventional push switch, the push switch 100 according to the embodiment can suppress the collision sound (that is, the operation sound) between the metal inversion dome 140 and the central fixed contact 112 .

[0099] (Relationship between the side cut ratio and the sound pressure of the metal inverted dome 140)

[0100] Fig. 9 : This is a graph showing the relationship between the side cut ratio and the sound pressure of the metal inverted dome 140 according to one embodiment. Fig. 9The graph shown shows measurement results of the sound pressure of the collision sound between the metal inverted dome 140 and the central fixed contact 112 when the side cut ratio of the metal inverted dome 140 is set to 40%, 50%, 60%, 70%, and 100%.

[0101] like Fig. 9 As shown in FIG. 1 , it is found that the larger the side cut ratio of the metal inverted dome 140 is, the higher the sound pressure of the collision sound between the metal inverted dome 140 and the central fixed contact 112 is. Fig. 9 As shown, it was found that by setting the side cut ratio of the metal inverted dome 140 within the range of 40% to 70%, the sound pressure of the collision sound between the metal inverted dome 140 and the central fixed contact 112 can be greatly reduced compared with the case where the side cut ratio of the metal inverted dome 140 is set to 100% (i.e., the case without a side cut shape).

[0102] (Relationship between the side cut ratio of the metal inverted dome 140 and the height of the dome shape)

[0103] Fig.10 : This is a graph showing the relationship between the side cut ratio and the height of the dome shape of the metal inverted dome 140 according to one embodiment. Fig.10 The graph shows measurement results of the dome-shaped height required to obtain a certain operating force of the metal inverted dome 140 when the side cut ratio of the metal inverted dome 140 was set to 40%, 50%, 60%, 70%, and 100%.

[0104] like Fig.10 As shown, it was found that the smaller the side cut ratio of the metal inverted dome 140 is, the higher the dome height is needed to obtain a certain operating force. In other words, it was found that even when the metal inverted dome 140 of one embodiment is formed in a side cut shape to suppress the collision sound, the same operating force as the metal inverted dome without a side cut shape can be obtained by setting the height of the dome shape to an appropriate height.

[0105] In addition, in the push switch 100 of one embodiment, the diameter of the metal inverted dome 140 is preferably set within a range of 3 mm to 8 mm. Thus, the push switch 100 of one embodiment can be miniaturized, and in the miniaturized push switch 100, the metal inverted dome 140 can provide a good operating feel to the operator.

[0106] In addition, in the push switch 100 of one embodiment, the thickness of the metal plate of the metal inverted dome 140 is preferably set within a range of 25 μm to 80 μm. Thus, in the push switch 100 of one embodiment, the metal inverted dome 140 can obtain good spring characteristics, and as a result, the metal inverted dome 140 can present a good operating tactile feeling to the operator.

[0107] In addition, in the push switch 100 of one embodiment, the material of the metal plate of the metal inverted dome 140 is preferably SUS301 or SUS304. Therefore, in the push switch 100 of one embodiment, the metal inverted dome 140 can obtain good spring characteristics, and as a result, the metal inverted dome 140 can present a good operating feel to the operator.

[0108] (A Modification of the Housing 110 and the Metal Inverted Dome 140)

[0109] Fig.11 It is a plan view showing a modified example of the housing 110 and the metal inverted dome 140 . Fig.11 The housing 110 - 2 shown is a modified example of the housing 110 . Fig.11 The metal inverted dome 140 - 2 shown is a modified example of the metal inverted dome 140 .

[0110] The housing 110-2 has a generally rectangular shape with the left-right direction (Y-axis direction) as the length direction when viewed from above. In addition, the housing 110-2 has a generally rectangular recess 110B with the left-right direction (Y-axis direction) as the length direction when viewed from above. A metal inverted dome 140-2 is accommodated inside the recess 110B of the housing 110-2.

[0111] The metal inverted dome 140-2 has a side cut shape in which both sides are cut in a straight line shape with respect to the front-back direction (X-axis direction) of the circular shape C when viewed from above. Specifically, the metal inverted dome 140-2 has a pair of left and right curved portions 141 along the circumference of the circular shape C and a pair of front and rear straight portions 142 parallel to each other. In addition, the circular shape C is a circle having a common center with the center (top 140A) of the metal inverted dome 140, and is a circle having a predetermined radius r.

[0112] Here, the metal inverted dome 140-2 has notch portions 143 in the shape of notch facing inwards formed in the front and rear straight portions 142. Thus, the metal inverted dome 140-2 has a narrow width portion 140B in the middle portion in the left-right direction (Y-axis direction) where the width is narrowed in the direction perpendicular to the direction in which the pair of straight portions 142 extend, that is, the front-back direction (X-axis direction).

[0113] Here, the metal inverted dome 140 - 2 has a diameter A and an interval B set so that the side cut ratio calculated by (B / A)×100 is within a range of 40% to 70%, similarly to the metal inverted dome 140 .

[0114] However, when the metal inverted dome 140 is used, the above-mentioned side cutting ratio is calculated by taking the interval between the pair of straight portions 142 as the interval B. However, in the metal inverted dome 140-2, since the narrow width portion 140B is provided, Fig.11 As shown, the above-mentioned side cutting ratio is calculated by taking the width of the narrow width portion 140B as the interval B.

[0115] When the push switch 100 includes the metal inverted dome 140-2 having the narrow width portion 140B, the operating load characteristics of the push switch 100 are determined not by the interval between the pair of straight portions 142 of the metal inverted dome 140-2 but by the width of the narrow width portion 140B of the metal inverted dome 140-2. Therefore, when the push switch 100 includes the metal inverted dome 140-2, the above-mentioned side cut ratio is calculated using the width of the narrow width portion 140B as the interval B.

[0116] Thus, even if the push switch 100 of one embodiment is provided Fig.11 In the case of the metal inversion dome 140-2 shown, compared with the previous push switch using a metal inversion dome that is circular when viewed from above (i.e., a metal inversion dome that is not side-cut), it is possible to present the same operating feel (i.e., good operating feel) to the operator. In addition, the reversal speed of the metal inversion dome 140 can be reduced, and the collision sound (i.e., operating sound) between the metal inversion dome 140 and the central fixed contact 112 can be suppressed.

[0117] Moreover, the metal inverted dome 140-2 is more preferably in the range of 60% to 70% in the same manner as the metal inverted dome 140. This is because when the side cutting ratio is higher, it is closer to a dome shape and can easily give the operator the same operating feel as a metal inverted dome without side cutting.

[0118] In addition, the metal inverted dome 140-2 is in contact with the inner wall portion 110Ba of the recess 110B of the housing 110-2 through a pair of front and rear straight portions 142, and is positioned in the front-rear direction (X-axis direction) and the rotation direction. On the other hand, the metal inverted dome 140-2 determines the operation load characteristics of the push switch 100 according to the width of the narrow width portion 140B. Therefore, when the push switch 100 uses the metal inverted dome 140-2, it is not necessary to change the dimensions of the metal inverted dome 140-2 and the recess 110B of the housing 110-2. By changing the shape of the notch portion 143 of the metal inverted dome 140-2 to adjust the width of the narrow width portion 140B, the operation load characteristics of the push switch 100 can be adjusted.

[0119] As mentioned above, although one embodiment of the present invention has been described in detail, the present invention is not limited to these embodiments, and various modifications and changes can be made within the scope of the gist of the present invention described in the claims.

Claims

1. A push switch, characterized in that: have: A housing having a recessed portion with an upper opening and a fixed contact in the interior of the recessed portion; a dome-shaped movable contact member, which is accommodated in the recessed portion of the housing and is formed of a metal plate; and The operating component presses the movable contact component to make the movable contact component perform a reverse action. The movable contact member, When viewed from above, it has a side cut shape formed by cutting both sides of a circular shape in a straight line shape. When the diameter of the circular shape is set to A and the interval between a pair of straight line portions formed by the cutting is set to B, the side cut ratio calculated by (B / A)×100 is in the range of 40% to 70%.

2. The push switch according to claim 1, wherein: The movable contact part is: The smaller the side cut ratio is, the higher the height of the dome shape is, so that a certain operating force of the reversing operation can be obtained.

3. The push switch according to claim 1, wherein: When the change in the operating load in the reversing action of the movable contact part is set to C and the change in the top in the reversing action of the movable contact part is set to D, the reversing action amount of the movable contact part calculated by C×D×1 / 2 is the same when the movable contact part has the side cut shape and when the movable contact part does not have the side cut shape.

4. The push switch according to claim 1, wherein: The diameter of the movable contact member is in the range of 3 mm to 8 mm.

5. The push switch according to claim 1, wherein: The thickness of the metal plate of the movable contact member is in the range of 25 μm to 80 μm.

6. The push switch according to claim 1, wherein: The material of the metal plate of the movable contact member is SUS301 or SUS304.

7. The push switch according to claim 1, wherein: The episiotomy ratio is in the range of 60% to 70%.

8. The push switch according to claim 1, wherein: The recessed portion of the housing has a gap portion at a position facing each of the pair of straight line portions of the movable contact member.

9. The push switch according to claim 8, characterized in that: The push switch includes a protection sheet that covers an upper surface of the housing and is bonded to the upper surface of the housing.

10. The push switch according to claim 1, wherein: The movable contact member, By providing a notch portion in each of the pair of straight portions, a narrow width portion having a narrowed width in a direction perpendicular to the direction in which the pair of straight portions extend is provided. The side cut ratio is calculated by using the width of the narrow width portion as B instead of the interval between the pair of straight line portions.

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