Microswitches and switching devices

Abstract

To provide a micro switch and switch device that suppress the positional deviation of an operating shaft while smoothly maintaining the operability of the operating shaft.SOLUTION: A micro switch 1 includes: a micro operating shaft 30 that applies force in the axial direction Z to switching means 40 that switches the conduction destination of a contact 50; an operating part 20 that moves the micro operating shaft 30 forward and backward in the axial direction Z; and a rotating shaft 23 that rotatably supports the operating part 20. The micro operating shaft 30 is provided with a contact part 31 that abuts the operating part 20, and the operating part 20 is provided with a bearing part 26 that supports the contact part 31. At least one of the contact part 31 and the bearing part 26 is provided with a first curved surface part a1 or a second curved surface part a2 that makes sliding contact with the other of the contact part 31 and the bearing part 26 in accordance with the rotation of the operating part 20.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a microswitch and a switch device. [Background Art]

[0002] Conventionally, devices equipped with a microswitch are known (see, for example, Patent Document 1). The thermostat described in Patent Document 1 includes a microswitch having a switch box that accommodates a contact mechanism, an operating shaft that reaches the switch box, and an L-shaped actuating plate that moves the operating shaft forward and backward in the axial direction. The L-shaped actuating plate includes a horizontally extending lateral side portion, a vertically extending longitudinal side portion, and a rotational fulcrum provided on the lower surface of the lateral side portion, and the operating shaft is inserted through the longitudinal side portion of the L-shaped actuating plate in the plate thickness direction. When the L-shaped actuating plate rotates about the rotational fulcrum, the operating shaft moves forward and backward in the axial direction following the rotation, thereby opening and closing the contact mechanism. [Prior Art Literature] [Patent Literature]

[0003] [Patent Document 1] Japanese Examined Patent Publication No. 05-042090 [Summary of the Invention] [Problem to be Solved by the Invention]

[0004] Incidentally, in a configuration like the thermostat described above, it is necessary to convert the rotational motion of the L-shaped operating plate into the axial movement of the operating shaft. To ensure this conversion is smooth, a predetermined clearance must be provided between the operating shaft and the portion of the L-shaped operating plate through which the operating shaft is inserted. However, in this case, if vibration or shock is applied to the operating shaft or the L-shaped operating plate, the position of the operating shaft changes within the clearance, which changes the amount of axial displacement of the operating shaft and can prevent the contact mechanism from opening and closing properly. On the other hand, if such a clearance is eliminated, the operating shaft will have difficulty following the rotational motion of the L-shaped operating plate, making it difficult to move the operating shaft back and forth.

[0005] The present invention aims to provide a microswitch and a switching device that suppress misalignment of the operating shaft while maintaining smooth operation of the operating shaft. [Means for solving the problem]

[0006] To solve the aforementioned problems and achieve the objective, the microswitch of the present invention comprises an operating shaft that applies force in the axial direction to a switching means that switches the conductive destination of a contact, an operating part that moves the operating shaft back and forth in the axial direction, and a pivot part that rotatably supports the operating part, wherein one end of the operating shaft in the axial direction is provided with a contact part that abuts against the operating part, the operating part is provided with a bearing part that supports the contact part, and at least one of the contact part and the bearing part is provided with a curved surface that slides against the other of the contact part and the bearing part as the operating part rotates. The curved surface portion is provided on both the contact portion and the bearing portion, and the curved surface portion on either the contact portion or the bearing portion is formed in a hemispherical shape, while the curved surface portion on the other of the contact portion or the bearing portion is formed in a conical shape, and the curved surfaces slide against each other in the circumferential direction around the axis of the operating shaft. It is characterized by the following:

[0007] According to this invention, a curved surface provided on at least one of the contact portion of the operating shaft and the bearing portion of the operating part is always in contact with the other of the contact portion and the bearing portion. This contact suppresses displacement of the operating shaft even when vibration or shock is applied to the operating shaft or operating part. Furthermore, with this configuration, the sliding contact between the curved surface and the contact portion or bearing portion allows the operating shaft to move back and forth appropriately in accordance with the rotational movement of the operating part, eliminating the need to provide the clearance required in the conventional microswitch described above. Therefore, it is possible to provide a microswitch that suppresses displacement of the operating shaft while maintaining smooth operation of the operating shaft.

[0008] Also, at this time, before The curved surface portion of the contact portion is formed in a hemispherical shape, and the curved surface portion of the bearing portion is formed in a conical shape. be This is preferable. With such a configuration, the area of ​​line contact between the contact portion and the bearing portion can be increased on the circumference around the axis of the operating shaft, so that misalignment of the operating shaft can be effectively suppressed.

[0009] Furthermore, the microswitch of the present invention comprises an operating shaft that applies force in the axial direction to a switching means for switching the conductive destination of a contact, an operating part that moves the operating shaft back and forth in the axial direction, and a pivot part that rotatably supports the operating part, wherein one end of the operating shaft in the axial direction is provided with a contact part that abuts against the operating part, the operating part is provided with a lever having an opposing surface facing the contact part, and a bearing part formed recessed in the opposing surface and supporting the contact part on its inner surface, the contact part is provided with a curved surface that slides against the bearing part as the operating part rotates, the curved surface is formed in an arc shape when viewed from the rotation axis direction of the pivot part and the arc has a shape that extends in the rotation axis direction, the bearing part has a pair of inclined surfaces that contact the contact part, and the curved surface makes line contact with one of the pair of inclined surfaces and the other Furthermore, the bearing portion is composed of a V-shaped groove when viewed in a cross-sectional view perpendicular to the rotation axis of the pivot point.This configuration is characterized by the fact that the curved portion provided on the contact portion can be made to make line contact with the inclined surface of the bearing portion at multiple points, thereby effectively suppressing misalignment of the operating shaft. Furthermore, with this configuration, the groove is formed in a relatively simple V-shape, and the curved surface of the contact portion makes line contact with the groove at multiple points, thereby effectively suppressing misalignment of the operating shaft.

[0011] Also, The microswitch of the present invention comprises an operating shaft that applies force in the axial direction to a switching means that switches the conductive destination of a contact, an operating part that moves the operating shaft forward and backward in the axial direction, and a pivot part that rotatably supports the operating part, wherein a contact part is provided on one end of the operating shaft in the axial direction that abuts against the operating part, the operating part is provided with a lever having an opposing surface facing the contact part, and a bearing part formed recessed in the opposing surface and supporting the contact part on its inner surface, the bearing part is provided with a curved surface that slides against the contact part as the operating part rotates, the curved surface is formed in an arc shape when viewed from the rotation axis direction of the pivot part and the arc has a shape that extends in the rotation axis direction, the contact part is formed in a rectangular shape in a cross-sectional view in a direction perpendicular to the rotation axis direction of the pivot part, and the first corner and second corner that constitute a part of the rectangular shape of the contact part are in contact with the curved surface. With this configuration, a curved surface is formed in the bearing section, and misalignment of the operating shaft can be effectively suppressed.

[0012] Furthermore, the switch device of the present invention is characterized by being equipped with any of the above-described microswitches. With such a configuration, the switch device can be constructed using a microswitch that suppresses misalignment of the operating shaft while maintaining smooth operation of the operating shaft. Examples of the switch device include a pressure switch that detects the pressure of the refrigerant in a refrigeration cycle, and a temperature switch that detects the temperature of the refrigerant. [Effects of the Invention]

[0013] According to the present invention, it is possible to provide a microswitch and a switch device that suppress misalignment of the operating shaft while maintaining smooth operation of the operating shaft. [Brief explanation of the drawing]

[0014] [Figure 1] A perspective view of a microswitch according to one embodiment of the present invention. [Figure 2] Cross-sectional view taken along line AA in Figure 1. [Figure 3] Enlarged cross-sectional view of the lever and micro-actuator shaft that constitute part of a microswitch. [Figure 4] Enlarged view of the main parts of the lever and micro-operating shaft. [Figure 5] Rear view of the lever. [Figure 6] Cross-sectional view taken along the line BB in Figure 5. [Figure 7] (A) is an enlarged cross-sectional view of the lever and micro-operating shaft according to the second embodiment, and (B) is an enlarged cross-sectional view of the groove portion of the operating part according to the second embodiment. [Figure 8] Enlarged view of essential parts of a lever and a micro operating shaft according to the second embodiment. [Figure 9] Rear view of the lever according to the second embodiment. [Figure 10] Cross-sectional view taken along line C-C of Figure 9. [Figure 11] (A) is an enlarged cross-sectional view of a lever and a micro operating shaft according to a third embodiment, and (B) is an enlarged view of essential parts of a lever and a micro operating shaft according to a modified example of the third embodiment. MODE FOR CARRYING OUT THE INVENTION

[0015] Hereinafter, an embodiment of the present invention will be described with reference to Figures 1 to 6. A microswitch 1 according to the present embodiment is, for example, mounted on a switching device such as a pressure switch that detects refrigerant pressure or a temperature switch that detects refrigerant temperature in a refrigerant cycle compressor, and constitutes a part of the switching device. The microswitch 1 includes: a box-shaped case 10; an operating unit 20 provided on an upper portion of the case 10; a micro operating shaft 30 (operating shaft) that is moved forward and backward in an axial direction by the operating unit 20; switching means 40 to which a force is applied when the micro operating shaft 30 is displaced in the axial direction; and a contact 50 whose conduction destination is switched by the switching means 40.

[0016] In the following description, in the drawings, arrows X, Y, and Z are directions orthogonal to each other. The moving direction of the micro operating shaft 30 described later is indicated by arrow Z, and is referred to as "axial direction Z". One side in the axial direction Z is referred to as "upper side Z1", and the other side is referred to as "lower side Z2". The horizontal directions are indicated by arrow X and arrow Y, which are referred to as "front-rear direction X" and "width direction Y", respectively. One side in the front-rear direction X is referred to as "front side X1", and the other side is referred to as "rear side X2". This is for convenience of description only, does not necessarily coincide with the directions of the microswitch 1 in the actual use state, and does not limit the respective directions of the microswitch 1 in the actual use state.

[0017] The case 10 comprises a roughly rectangular box-shaped box portion 11 and a lid portion 12 provided on the upper side Z1 of the box portion 11. As shown in Figure 2, the box portion 11 has an internal storage space 13. Components such as the switching means 40 and contacts 50 are housed in the storage space 13. A projection 14 is formed on the rear side wall X2 of the side wall of the box portion 11, projecting outwards to the rear X2. The projection 14 is a part for fixing the box portion 11 to a device on which the microswitch 1 is mounted (for example, a device such as the pressure switch described above), and together with the base portion 15 described later, it constitutes a connection portion for connecting the box portion 11 to the device. The lid portion 12 comprises a base portion 15 positioned on the upper side Z1 of the projection portion 14 and extending upward to Z1, and a lid body 16 that is continuous with the base portion 15 and extends in the front-rear direction X perpendicular to the base portion 15. The base portion 15 is formed in a thick plate shape and, together with the aforementioned protruding portion 14, constitutes the connection portion of the joint pipe.

[0018] On the surface of the base portion 15 facing the front X1, there are two pairs of projections 15a, each projecting forward in the width direction Y, spaced apart in the width direction Y. Between the pairs of projections 15a, a rectangular parallelepiped base 17 is formed, projecting forward from the surface of the base portion 15 facing the front X1. A fixing part 18 for fixing the lever 22, which will be described later, is fixed to the base 17 by a fastening member 19. The fixing part 18 is formed by bending a metal plate, and covers the upper surface Z1 and both sides in the width direction Y of the base 17, and protrudes forward in the front X1 beyond the end of the front X1 of the base 17. The lid body 16 is formed in the shape of a rectangular plate extending in the front-rear direction X and the width direction Y, and a through hole 16a is formed through its center, penetrating in the axial direction Z.

[0019] The operating part 20 is the part that moves the micro-operating shaft 30 forward and backward in the axial direction Z by being displaced by an external force. An example of an external force is the force generated and transmitted when the bellows, which acts as a sensing element, is displaced in response to a change in the pressure or temperature of the refrigerant, when the microswitch 1 is used as a pressure switch to detect the pressure of the refrigerant or a temperature switch to detect the temperature of the refrigerant. In this case, the operating part 20 functions as a displacement transmission member that transmits the displacement of the bellows, etc., to the micro-operating shaft 30. As shown in Figure 3, the operating part 20 comprises a support part 21, a lever 22 as an operating fitting positioned on the front side X1 of the support part 21, and a rotating shaft 23 (fulcrum) connecting the support part 21 and the lever 22. The support part 21 is fixed to the case 10 and supports the lever 22. The lever 22 is provided so as to be rotatable around the axis of the rotating shaft 23 (counterclockwise in this embodiment when viewed from the direction shown in Figure 3) by being subjected to the external force described above, with the rotating shaft 23 as the fulcrum.

[0020] As shown in Figures 5 and 6, the lever 22 comprises a flat plate-shaped pressing plate portion 24 extending in the width direction Y and the front-rear direction X, and side wall portions 25 rising from both ends of the pressing plate portion 24 in the width direction Y to the lower side Z2. A bearing portion 26 is formed in the central rear portion X2 of the pressing plate portion 24, opening to the lower side Z2 and projecting conically toward the upper side Z1. The inner surface of the bearing portion 26 is conically recessed and constitutes a first curved surface portion a1 (curved surface portion) that slides against the contact portion 31 of the micro-operating shaft 30, which will be described later. That is, the first curved surface portion a1 of the bearing portion 26 is formed in a conical shape and supports the micro-operating shaft 30 via the contact portion. The rear end X2 of the side wall portion 25 protrudes to the rear X2 from the rear end X2 of the pressing plate portion 24, and this protruding portion constitutes an insertion portion 27 through which the rotating shaft 23 is inserted in the width direction Y. The rotating shaft 23 is an axis that rotatably supports the lever 22. The rotating shaft 23 passes through both side walls in the width direction Y of the fixed part 18 which is fixed to the base 17, and also passes through the front end X1 of the support part 21 and the insertion part 27 of the lever 22 in the width direction Y, and is fixed to the fixed part 18.

[0021] The micro-actuator shaft 30 is a shaft member that moves forward and backward in the axial direction Z in accordance with the rotational movement of the lever 22 in the actuator 20. It is inserted through the insertion hole 16a of the cover body 16 described above, extends in the axial direction Z, and is fixed to the case 10 so as to be displaceable in the axial direction Z. As shown in Figure 2, the micro-actuator shaft 30 has a contact portion 31 formed at the upper end (one end) of the upper Z1 located outside the case 10, and an engaging portion 32 that constitutes the lower end of the lower Z2 located inside the case 10. As shown in Figures 3 and 4, the contact portion 31 is the part that contacts the bearing portion 26 of the lever 22, and its outer surface constitutes a hemispherical second curved surface portion a2. The second curved surface portion a2 can slide against the first curved surface portion a1 in the circumferential direction around the axis of the micro-actuator shaft 30 as the lever 22 rotates.

[0022] In other words, curved surfaces (first curved surface a1 and second curved surface a2) are provided on both the contact surface 31 and the bearing surface 26, and the curved surfaces slide against each other in the circumferential direction around the axis of the micro-operating shaft 30. To put it another way, at least one of the contact surface 31 and the bearing surface 26 is provided with a curved surface that slides against the other of the contact surface 31 and the bearing surface 26 as the lever 22 rotates. The engaging surface 32 is the part that engages with the switching means 40, and when this engaging surface 32 engages with the switching means 40, an axial force Z acts on the switching means 40 when the micro-operating shaft 30 moves forward and backward.

[0023] As shown in Figure 2, the switching means 40 includes a movable piece 41 that engages with the engagement portion 32 of the micro-operating shaft 30, a snap piece 42 that abuts the tip of the movable piece 41 and biases the movable contact 53 (described later) toward the first fixed contact 51 or the second fixed contact 52, and a conductive piece 43 with the movable contact 53 at its front X1 end. The contact 50 is a conductive member connected to a plurality of terminals (not shown) provided on the case 10, and includes a first fixed contact 51, a second fixed contact 52, and a movable contact 53 fixed to the front X1 end of the conductive piece 43. The first fixed contact 51 is fixed to the case 10 within the housing space 13 of the case 10 and is connected to a first terminal (not shown). The second fixed contact 52 is located above the first fixed contact 51 Z1 and is fixed to the case 10 within the housing space 13, facing the first fixed contact 51 in the axial direction Z. The second fixed contact 52 is connected to a first terminal (not shown). The movable contact 53 is positioned between the first fixed contact 51 and the second fixed contact 52, and is electrically conductive when it comes into contact with the first fixed contact 51 and the second fixed contact 52, respectively.

[0024] The operation of the microswitch 1 will now be described. Here, the microswitch 1 is mounted on the pressure switch that detects the refrigerant pressure as described above, and switches the destination of the contact 50 between a low-pressure state where the refrigerant pressure is small and a high-pressure state where the refrigerant pressure is a predetermined amount greater than the low-pressure state. Figure 2 shows the microswitch 1 when the refrigerant is in a low-pressure state. In this state, the operating part 20 does not press the micro operating shaft 30 downward Z2, and the movable contact 53, which is biased downward Z2 by the snap piece 42, contacts the first fixed contact 51 and conducts electricity, detecting that it is in a low-pressure state. Next, when the refrigerant pressure rises, pressure acts on the bellows of the pressure switch, causing the bellows to displace, and this displacement is transmitted to the operating part 20 via a transmission member (not shown), applying an external force downward Z2 to the operating part 20. As a result, as shown in Figure 3, the lever 22 of the operating part 20 rotates counterclockwise around the axis of the rotation shaft 23. In this process, as the lever 22 rotates, the first curved surface a1 of the bearing portion 26 slides against the second curved surface a2 of the contact portion 31 of the micro-operating shaft 30, thereby transmitting the rotational force of the lever 22 to the micro-operating shaft 30.

[0025] Next, due to the sliding contact described above, the micro-actuator shaft 30 is displaced downward Z2 in accordance with the rotation of the lever 22. As the micro-actuator shaft 30 is displaced downward Z2, a pressing force toward downward Z2 acts on the switching means 40, causing the movable piece 41 to deform, and in conjunction with the deformation of the movable piece 41, the snap piece 42 deforms. When the amount of deformation of the snap piece 42 exceeds a certain amount, the biasing force on the conductive piece 43 reverses, and the conductive piece 43 is biased upward Z1. As a result, the conductive state between the movable contact 53 and the first fixed contact 51 is released, and the movable contact 53 and the second fixed contact 52 come into contact and become conductive. In other words, the switching means 40 switches the conductive destination of the contact 50. This allows detection that the microswitch 1 has switched from a low-voltage state to a high-voltage state.

[0026] In this embodiment, Figure 2 shows the microswitch 1 when the refrigerant is in a low-pressure state. However, conversely, Figure 2 may also show the microswitch 1 when the refrigerant is in a high-pressure state. That is, the high-pressure state may be detected in the state shown in Figure 2. Then, when the refrigerant pressure decreases from this state, the bellows is displaced, this displacement is transmitted to the operating unit 20, the micro operating shaft 30 is displaced downward Z2, the biasing force of the snap piece 42 is reversed, the conductivity between the movable contact 53 and the first fixed contact 51 is released, and conductivity between the movable contact 53 and the second fixed contact 52 is established, and it may be detected that the microswitch 1 has switched from a high-pressure state to a low-pressure state.

[0027] Furthermore, in this embodiment, the operation of the microswitch 1 was described as being mounted on a pressure switch that detects the pressure of the refrigerant. However, this is merely an example, and the same principle applies if, for example, the microswitch 1 is mounted on a temperature switch that detects the temperature of the refrigerant, and switches the destination of the contact 50 between a low-temperature state where the refrigerant temperature is low and a high-temperature state where the refrigerant temperature is a predetermined amount higher than the low-temperature state. In this case, for example, the state in Figure 2 is the state where the refrigerant is in the low-temperature state. As the temperature of the refrigerant rises from here, the bellows expands and displaces, and this displacement is transmitted to the operating unit 20 via a transmission member (not shown), applying an external force to the operating unit 20 toward the downward Z2. As a result, similar to the case of a pressure switch, the micro operating shaft 30 is displaced toward the downward Z2, the load generated by this displacement acts on the switching means 40, the biasing force by the snap piece 42 is reversed, the conductivity between the movable contact 53 and the first fixed contact 51 is released, and conductivity between the movable contact 53 and the second fixed contact 52 is restored. This allows detection that microswitch 1 has switched from a low temperature state to a high temperature state.

[0028] As described above, according to the embodiment described above, the curved surfaces (first curved surface a1, second curved surface a2) provided on at least one of the contact portion 31 of the micro-acting shaft 30 and the bearing portion 26 of the operating portion 20 are always in contact with the other of the contact portion 31 and the bearing portion 26. This contact suppresses displacement of the micro-acting shaft 30 even when vibration or shock is applied to the micro-acting shaft 30 or the operating portion 20. Furthermore, with this configuration, the sliding contact between the first curved surface a1 and the second curved surface a2 allows the micro-acting shaft 30 to move back and forth appropriately in accordance with the rotational movement of the operating portion 20, eliminating the need to provide the clearance required in the conventional microswitch described above. Therefore, it is possible to provide a microswitch 1 that suppresses displacement of the micro-acting shaft 30 while maintaining smooth operation of the micro-acting shaft 30. Furthermore, according to this embodiment, since curved surfaces are provided on both the contact portion 31 and the bearing portion 26, the area of ​​line contact between the contact portion 31 and the bearing portion 26 can be increased on the circumference around the axis of the operating shaft, and the displacement of the micro operating shaft 30 can be effectively suppressed. In addition, according to the above-described embodiment and its modifications, a microswitch 1 that suppresses the displacement of the micro operating shaft 30 while maintaining the smooth operation of the micro operating shaft 30 can be used to construct a switch device such as a pressure switch or a temperature switch.

[0029] Next, a second embodiment of the present invention will be described. Figure 7(A) is an enlarged cross-sectional view of the lever 22 and micro-actuator shaft 30 according to the second embodiment, and Figure 7(B) is an enlarged cross-sectional view of the groove portion 28 of the actuator 20 according to the second embodiment. Figure 8 is an enlarged view of the main parts of the lever 22 and micro-actuator shaft 30 according to the second embodiment. Figure 9 is a rear view of the lever 22 according to the second embodiment, and Figure 10 is a cross-sectional view taken along the line C and C in Figure 9. As shown in Figure 9, in the second embodiment, a through hole 24a is formed in the pressing plate portion 24 of the actuator 20. Bearing portions 260 protruding toward the upper side Z1 are formed on both sides of the through hole 24a in the width direction Y. As shown in Figure 7(B), the inner surface of the bearing portion 260 constitutes a V-shaped groove portion 28 in cross-sectional view, which is composed of a first inclined surface 28a (shown only in Figure 7(B)) located on the lower side Z2 as it moves toward the front side X1, and a second inclined surface 28b (shown only in Figure 7(B)) located on the lower side Z2 as it moves toward the rear side X2.

[0030] As shown in Figure 10, the micro-actuator shaft 30 is formed in a plate shape extending in the width direction Y and the axial direction Z. An insertion projection 33 is formed at the upper end Z1 of the micro-actuator shaft 30, protruding from the upper Z1. The insertion projection 33 is a projection that is inserted into the through hole 24a of the pressing plate portion 24, and as shown in Figure 9, it consists of a first insertion projection 33a which is rectangular in rear view, and a second insertion projection 33b which is positioned X1 in front of the first insertion projection 33a and has a smaller dimension in the width direction Y than the first insertion projection 33a. The difference in the width direction Y dimensions of the first insertion projection 33a and the second insertion projection 33b prevents the orientation of the micro-actuator shaft 30 in the front-to-back direction X from being reversed when the micro-actuator shaft 30 is installed.

[0031] Contact portions 310 are formed on both sides of the insertion projection 33 in the width direction Y, and contact portions 310 are formed to abut against the groove portion 28. The contact portion 310 constitutes a third curved surface portion a3 (curved surface portion) whose outer surface is formed in an arc shape when viewed from the side. The third curved surface portion a3 contacts the first inclined surface 28a and the second inclined surface 28b of the groove portion 28 in two lines. Thus, the third curved surface portion a3 (curved surface portion) is formed in an arc shape and provided on the contact portion 310, and the bearing portion 260 is equipped with a pair of inclined surfaces (first inclined surface 28a, second inclined surface 28b) that contact the contact portion 310, and the third curved surface portion a3 makes line contact with the pair of inclined surfaces at multiple points.

[0032] In the second embodiment, the microswitch 1 operates in the same manner as in the first embodiment described above. That is, when the pressure or temperature of the refrigerant changes, pressure acts on the bellows of the pressure switch, causing the bellows to displace. This displacement is transmitted to the operating part 20 via a transmission member (not shown), applying an external force downward Z2 to the operating part 20, which causes the lever 22 to rotate around the axis of the rotation shaft 23. When the lever 22 rotates, the third curved surface a3 of the micro operating shaft 30 slides against the groove 28 of the bearing part 260, and the rotational force of the lever 22 is transmitted to the micro operating shaft 30. With this configuration, the third curved surface a3 provided on the contact part 310 can be made to line contact with the inclined surface of the bearing part 260 at multiple points, thus effectively suppressing displacement of the micro operating shaft 30. In this embodiment, the part that slides against the third curved surface a3 is configured as a groove 28 with a simple V-shape in cross-section, but this is merely an example, and the shape of the sliding contact part can be adjusted as appropriate. For example, a flat surface or an arc-shaped surface extending in the front-rear direction X may be added as a connecting surface between the pair of inclined surfaces described above (first inclined surface 28a, second inclined surface 28b). Alternatively, a bearing portion 260 may be formed by adding multiple inclined surfaces with different inclination angles from the first inclined surface 28a and the second inclined surface 28b as connecting surfaces between the first inclined surface 28a and the second inclined surface 28b.

[0033] Next, a third embodiment of the present invention will be described. Figure 11(A) is an enlarged view of the main parts of the lever 22 and micro actuation shaft 30 according to the third embodiment. In the third embodiment, as shown in Figure 11(A), a bearing portion 261 protruding upward Z1 is formed on the pressing plate portion 24 of the lever 22. The inner surface of the bearing portion 261 constitutes a fourth curved surface portion a4 that is recessed in the shape of a circular arc in cross-section. The upper end of the micro actuation shaft 30 on the upward Z1 is a contact portion 311 that slides against the fourth curved surface portion a4. The contact portion 311 is formed in a rectangular shape in the cross-sectional view shown in Figure 11(A). The contact portion 311 has a first corner portion 34 and a second corner portion 35 that contact the fourth curved surface portion a4. That is, the contact portion 311 contacts the fourth curved surface portion a4 in two lines via the first corner portion 34 and the second corner portion 35. In the third embodiment as well, the micro switch 1 operates in the same manner as in the first and second embodiments described above. In this case, when the lever 22 rotates around the axis of the rotating shaft 23, the first corner 34 and the second corner 35 of the contact portion 311 of the micro-operating shaft 30 slide against the fourth curved surface a4 of the bearing portion 261, and the rotational force of the lever 22 is transmitted to the micro-operating shaft 30.

[0034] Next, a modified example of the third embodiment will be described. Figure 11(B) is an enlarged view of the main parts of the lever 22 and micro-actuator shaft 30 according to the modified example of the third embodiment. As shown in Figure 11(B), in the modified example of the third embodiment, a through hole 24a similar to that of the second embodiment is formed in the pressing plate portion 24 of the lever 22. On both sides of the through hole 24a in the width direction Y, bearing portions 262 protruding upward Z1 are formed. The inner surface of the bearing portion 262 constitutes a fifth curved surface portion a5 which is concave in a hemispherical cross-section. The contact portion 311 of the micro-actuator shaft 30 slides against the fifth curved surface portion a5 in two or more lines by the first corner portion 34 and the second corner portion 35. In the modified example of the third embodiment, the microswitch 1 operates in the same manner as in the first, second, and third embodiments described above. When the lever 22 rotates around the axis of the rotating shaft 23, the contact portion 311 of the micro-operating shaft 30 slides against the fifth curved surface portion a5 of the bearing portion 262 over two or more lines, and the rotational force of the lever 22 is transmitted to the micro-operating shaft 30. According to this third embodiment and its modified form, curved surfaces (fourth curved surface portion a4, fifth curved surface portion a5) are formed on the bearing portions 261 and 262, and displacement of the micro-operating shaft 30 can be effectively suppressed.

[0035] The embodiments described above are merely representative forms of the present invention, and the present invention is not limited thereto. That is, it can be implemented with various modifications without departing from the core principles of the present invention. As long as such modifications still possess the configuration of the microswitch 1 of the present invention, they are of course included within the scope of the present invention. For example, in the embodiments and modifications described above, the curved surface on the micro-actuator shaft 30 side is formed in a convex shape toward the bearing portion 26 side, but conversely, the curved surface on the micro-actuator shaft 30 side may be formed in a concave shape toward the bearing portion 26 side, and the bearing portion 26 side may be convex. Similarly, the curved surface on the bearing portion 26 side may be formed in a convex shape toward the micro-actuator shaft 30 side. In this case, a groove portion having the pair of inclined surfaces (first inclined surface 28a, second inclined surface 28b) described above may be formed on the micro-actuator shaft 30 side. That is, at least one of the contact portion 31 and the bearing portion 26 should be provided with a curved surface portion that slides against the other of the contact portion 31 and the bearing portion 26 as the actuator 20 rotates. [Explanation of Symbols]

[0036] a1 First curved surface part (curved surface part) Z axis direction 1 microswitch 20 Operating part 23. Rotation axis (pivot point) 26 Bearing section 30 micro-actuated shaft (actuated shaft) 31 Contact part 40 Switching means 50 contacts

Claims

1. An operating shaft that applies force in the axial direction to a switching mechanism that switches the conductive destination of a contact, An operating part that moves the operating shaft forward and backward in the axial direction, It comprises a pivot point that rotatably supports the aforementioned operating part, A contact portion is provided on one end of the operating shaft in the axial direction, which contacts the operating part. The operating part is provided with a bearing that supports the contact part, At least one of the contact portion and the bearing portion is provided with a curved surface that slides against the other of the contact portion and the bearing portion as the operating portion rotates. The curved portion is provided on both the contact portion and the bearing portion. The curved surface portion of either the contact portion or the bearing portion is formed in a hemispherical shape. The other of the contact portion or the bearing portion is formed in a conical shape. A microswitch characterized in that the curved surfaces slide against each other in the circumferential direction around the axis of the operating shaft.

2. The curved portion of the contact part is formed in a hemispherical shape. The microswitch according to claim 1, characterized in that the curved surface portion of the bearing portion is formed in a conical shape.

3. An operating shaft that applies force in the axial direction to a switching mechanism that switches the conductive destination of a contact, An operating part that moves the operating shaft forward and backward in the axial direction, It comprises a pivot point that rotatably supports the aforementioned operating part, A contact portion is provided on one end of the operating shaft in the axial direction, which contacts the operating part. The operating part is provided with a lever having an opposing surface facing the contact portion, and a bearing portion formed recessed in the opposing surface and supporting the contact portion on its inner surface. The contact portion is provided with a curved surface that slides against the bearing portion as the operating portion rotates. The curved portion is formed in an arc shape when viewed from the axis of rotation of the pivot point, and the arc has a shape that extends in the direction of the axis of rotation. The bearing portion comprises a pair of inclined surfaces that contact the contact portion, The curved portion makes line contact with one of the pair of inclined surfaces and the other, respectively. The microswitch is characterized in that the bearing portion is composed of a V-shaped groove when viewed in a cross-sectional view in a direction perpendicular to the rotation axis of the pivot portion.

4. A switch device characterized by being equipped with a microswitch according to any one of claims 1 to 3.

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