Microswitch and pressure response switch

Abstract

The invention provides a microswitch and a pressure response switch which can stably maintain the conduction state of a contact. A switching member (50) of a microswitch (1) is provided with an inner spring (60), an outer spring (70), and a reverse spring (80). The inner spring (60) deforms in accordance with the movement of the operating shaft (20), the reverse spring (80) biases the outer spring (70) in accordance with the deformation of the inner spring (60), and the outer spring (70) is biased and biased by the reverse spring (80) and presses the movable contact (44) toward the fixed contact (41). The range of movement of the operating shaft (20) includes a reverse position (gamma) at which a reverse action is generated when the operating shaft (20) passes, and the inner spring (60) is provided with a hole (90) for being in a deformed state of deflection in a state where the operating shaft (20) is in the reverse position (gamma). When the inner spring (60) is in a deformed state, the reverse spring (80) generates a biasing force that maintains a state in which the outer spring (70) presses the movable contact (44) toward the fixed contact (41).

Description

Technical Field

[0001] The invention relates to a micro switch and a pressure response switch. Background Art

[0002] Conventionally, there is known a micro switch (mechanical switch) for switching the conductive state of a contact (for example, see Patent Document 1). Figure 1 As shown, the micro switch described in patent document 1 has a movable contact 2a arranged between a fixed contact 4 and a contact 9, a leaf spring 3 that turns the movable contact 2a on (ON) or off (OFF), and a pressing piece 5 acting on the leaf spring 3. The leaf spring 3 includes an inner working piece 3a pressed by the pressing piece 5, an outer working piece 3b connected to the movable contact 2a, and a leaf spring 3c connecting the inner working piece 3a and the outer working piece 3b. In this micro switch, when the pressing force of the pressing piece 5 is balanced with the rebound force of the leaf spring 3, the movable contact 2a is separated from the fixed contact 4 and is turned off (OFF). On the other hand, when the pressing force of the pressing piece 5 is above a predetermined pressure, the inner working piece 3a is pressed, whereby the leaf spring 3c is reversed, thereby pushing the outer working piece 3b upward, so that the movable contact 2a contacts the fixed contact 4 and is turned on (ON).

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Laid-Open No. 9-63417 Summary of the invention

[0006] Technical issues

[0007] However, in the micro switch, for example, from the OFF state where the movable contact 2a and the fixed contact 4 are separated to the state before the pressing plate 5 is pressed and the leaf spring 3c is reversed, a chattering phenomenon in which the movable contact 2a and the fixed contact 4 repeatedly contact and separate is likely to occur. Therefore, in the state before the leaf spring 3c is reversed, it is difficult to stably maintain the conductive state of the movable contact 2a. For example, this is easily apparent when the micro switch is mounted on a device that is prone to generating an unexpected external force due to vibration, pressure fluctuation, etc., such as a pressure response switch for detecting the pressure of the refrigerant in a refrigeration cycle system.

[0008] An object of the present invention is to provide a micro switch and a pressure response switch capable of stably maintaining a conductive state of a contact.

[0009] Technical Solution

[0010] In order to solve the above-mentioned problems and achieve the purpose, according to the present invention, a micro switch is provided, which comprises a movable contact arranged between a pair of fixed contacts, a working shaft moving in an advance and retreat direction, and a switching member that performs a reverse action as the working shaft moves to make the movable contact conductive with one or the other of the pair of fixed contacts. The micro switch is characterized in that the switching member comprises a working spring connected to the working shaft, an action spring holding the movable contact, and a reversing spring connecting the working spring and the action spring, the working spring being configured to be deformable as the working shaft moves, and the reversing spring being configured to be deformable according to the movement of the working shaft. The deformation of the working spring applies force to the action spring, and the action spring is configured to be able to be urged by the reversal spring to press the movable contact toward one or the other of the pair of fixed contacts. The moving range of the working shaft includes a reversal position after passing through which the reversal action is generated. The working spring is provided with a rigidity reducing component, which is used to be in a flexural deformation state when the working shaft is located at the reversal position. The deformation state is achieved by the working spring, and the reversal spring generates a force to maintain the state of the action spring pressing the movable contact toward one or the other of the pair of fixed contacts.

[0011] According to the present invention, by providing a rigidity reducing member in the working spring, when the working shaft is in the reversing position, that is, in the state before the reversing action occurs, the working spring can be placed in a deformed state. Furthermore, when the working spring is in a deformed state, the reversing spring can generate a force that maintains the state in which the working spring presses the movable contact toward the fixed contact. Therefore, even before the reversing action, the state in which the movable contact is pressed toward the fixed contact can be reliably maintained, and even when an unexpected external force such as vibration or pressure fluctuation occurs, chattering can be suppressed. Therefore, a micro switch that can stably maintain the conductive state of the contact can be provided.

[0012] In this case, the fixed contact may include a first fixed contact and a second fixed contact arranged on the retreat side in the forward and retreat direction relative to the first fixed contact, the reversal position includes a first reversal position where the reversal action occurs after the working shaft passes toward the forward side in the forward and retreat direction, and a second reversal position where the reversal action occurs after the working shaft passes toward the retreat side, and the movable contact is pressed toward the first fixed contact when the working shaft moving toward the forward side is located at the first reversal position; and the movable contact is pressed toward the second fixed contact when the working shaft moving toward the retreat side is located at the second reversal position. According to this structure, the present invention can be applied to a micro switch of a type in which the reversal action occurs when the conduction destination of the movable contact is switched from the first fixed contact to the second fixed contact (first reversal position) and the reversal position (second reversal position) where the conduction destination of the movable contact is switched from the second fixed contact to the first fixed contact, and the movable contact is kept pressed toward the fixed contact before the reversal action occurs.

[0013] In addition, preferably, the switching member includes an inner spring as the working spring extending in a direction intersecting the advancing and retreating direction and formed in a plate shape, an outer spring as the action spring surrounding the inner spring and formed in a plate shape, and the reversing spring, the inner spring including an abutting portion abutting against the working axis, and the rigidity reducing member reduces the rigidity of the inner spring as it moves from the side where the abutting portion is located toward the side where the connection portion with the reversing spring is located. According to this structure, the rigidity reducing member reduces the rigidity of the inner spring as it moves toward the side where the connection portion is located, so that the side where the connection portion of the inner spring is located can be deformed more easily than the side where the working axis of the inner spring is located. As a result, the deformed state of the inner spring can be maintained more easily on the side where the connection portion is located. Therefore, before the reverse rotation, it is easier to maintain the force of the outer spring on the reversing spring, and the state in which the outer spring presses the movable contact toward the fixed contact can be stably maintained. In addition, according to this structure, it is easy to increase the rigidity of the side where the working axis of the inner spring is located, so that the durability of the side where the working axis of the inner spring is located can be improved.

[0014] In addition, the rigidity reducing member may be a hole portion penetrating in the plate thickness direction of the inner spring. According to this structure, the rigidity reducing member can be provided on the micro switch by a simple method of forming the hole portion on the inner spring.

[0015] In addition, preferably, the dimension of the hole portion in the width direction increases as it approaches the connection portion. According to this structure, by increasing the dimension of the hole portion in the width direction as it approaches the connection portion, the volume of the inner spring can be reduced as it approaches the connection portion side, and increased as it approaches the abutment portion side. Therefore, the rigidity of the inner spring can be reduced as it approaches the connection portion side, and the connection portion side of the inner spring can be deformed more easily than the working axis side of the inner spring. As a result, it is easier to maintain the deformed state of the inner spring on the connection portion side.

[0016] In addition, the rigidity reducing member may be formed by a cutout portion formed by cutting the inner spring in the width direction. According to this structure, the rigidity reducing member can be provided on the micro switch by a simple method of forming the cutout portion by cutting the inner spring.

[0017] In addition, the pressure responsive switch of the present invention is characterized by comprising the above-mentioned micro switch. According to this structure, the pressure responsive switch can be constructed by mounting a micro switch capable of stably maintaining the conductive state of the contact.

[0018] Effects of the Invention

[0019] According to the present invention, a micro switch and a pressure responsive switch capable of stably maintaining the conductive state of a contact point can be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a bottom view of a pressure responsive switch equipped with a micro switch according to an embodiment of the present invention.

[0021] Figure 2 It is a three-dimensional diagram of a micro switch.

[0022] Figure 3 is along Figure 2 A cross-sectional view taken along line AA in FIG.

[0023] Figure 4 is a plan view showing a part of the switching member.

[0024] Figure 5 is a schematic diagram showing the switching member in the initial state.

[0025] Figure 6 (A) is a schematic diagram of a switching member showing a state where the working shaft is located at a first reversal position, Figure 6 (B) is a schematic diagram showing a state where the operating shaft is located at the first reversal position in the switching member not having the rigidity reducing member.

[0026] Figure 7 1 is a plan view showing a part of a switching member in a modified example.

[0027] Reference numerals

[0028] Z: up and down direction (advance and retreat direction), γ: reversal position, 1: micro switch, 20: working axis, 41: fixed contact, 42: first fixed contact (one of a pair of fixed contacts), 43: second fixed contact (the other of a pair of fixed contacts), 44: movable contact, 50: switching member, 60: inner spring (working spring), 70: outer spring (action spring), 80: reversal spring, 90: hole portion (rigidity reducing member). DETAILED DESCRIPTION

[0029] The following is an explanation of one embodiment of the present invention. The micro switch 1 of this embodiment is mounted on a pressure response switch 100 for detecting a pressure change of a fluid or a temperature change of a fluid, and detects a pressure change or a temperature change of the fluid in, for example, a refrigeration cycle, an automobile, a driver for various controls, etc., which uses a working medium as a fluid.

[0030] In the following description, in the figure, the axial direction of the working shaft 20 described later is indicated by an arrow Z and recorded as "upper and lower direction Z". In addition, one side of the upper and lower direction Z is recorded as "lower side Z1", and the other side is recorded as "upper side Z2". In addition, the upper and lower direction Z is the "advance and retreat direction" in the present invention, the lower side Z1 is the "advance side" in the present invention, and the upper side Z2 is the "retreat side" in the present invention. In addition, the horizontal direction (the intersection direction in the present invention) intersecting the upper and lower direction Z is indicated by an arrow X and an arrow Y, and recorded as "front and rear direction X" and "left and right direction Y" respectively. In addition, one side of the front and rear direction X is recorded as "front side X1", and the other side is recorded as "rear side X2", one side of the left and right direction Y is recorded as "left side Y1", and the other side is recorded as "right side Y2". The definitions of these directions are only for the convenience of explanation, and are not necessarily consistent with the directions in the actual use state of the micro switch 1, and do not limit the directions in the actual use state of the micro switch 1.

[0031] like Figure 1As shown, the pressure response switch 100 includes a housing 110 that is generally rectangular in shape. The housing 110 includes a C-shaped main frame 111 that opens to the lower side Z1, and a cover (not shown) that closes the opening of the main frame 111, and contains various components such as the micro switch 1 described later. The main frame 111 is formed by bending a metal plate, etc., and includes a front wall portion 112, a side wall portion 113, a rear wall portion 114, and a top wall portion 115. A pair of elements 116 and a pair of joint pipes 117 respectively connected to the pair of elements 116 are connected to the rear wall portion 114 of the housing 110. The element 116 includes a sensing component such as a bellows or a diaphragm (not shown) inside. The sensing component deforms or displaces in the front-rear direction X according to the pressure change of the pressure fluid introduced through the joint pipe 117.

[0032] A pair of left and right transmission members 118 and a pair of left and right switch components 119 are accommodated inside the housing 110. The transmission member 118 includes a reinforcing plate 120 formed into a C-shape opening to the upper side Z2 by bending a metal plate, and a transmission component 121 is accommodated inside the reinforcing plate 120. An example of the transmission component 121 is a working plate 122, which receives the force of deformation or displacement of the above-mentioned sensing component as an external force, and converts the external force into an operating force by rotating around a rotating shaft 123, and transmits the operating force to the connecting rod 17 described later. The switch component 119 includes a plurality of contacts 40 described later, and receives the above-mentioned operating force to change the conductive state of the contacts 40. A pair of switch components 119 are arranged adjacent to each other in the left-right direction Y, and constitute a double-type micro switch 1. Figure 2 is a three-dimensional diagram of a micro switch 1. Figure 3 is along Figure 2 A cross-sectional view taken along line AA in FIG.

[0033] like Figure 2As shown, the micro switch 1 includes a box portion 10. The box portion 10 is formed of, for example, a resin material into a substantially cubic shape, and a storage space 11 for accommodating various components is formed inside the box portion 10. A connecting portion 13 protruding toward the rear side X2 is formed on the rear wall 12 of the box portion 10. The connecting portion 13 is formed in a plate shape extending in the up-down direction Z, and is fixed to the top wall portion 115 of the housing 110 of the pressure response switch 100. A rectangular box-shaped fixing component 15 is mounted on the upper wall 14 of the box portion 10. In the present embodiment, a pair of fixing components 15 are arranged and installed in a row along the left-right direction Y. A rotating shaft 16 extending in the left-right direction Y is fixed to the side wall of each fixing component 15, and a connecting rod 17 is mounted on the rotating shaft 16 so as to be rotatable around the axis. That is, a pair of connecting rods 17 are provided. In addition, in the present embodiment, "rotation" means forward and reverse rotation around the rotating shaft 16 within a predetermined angle range. The link 17 is a plate-shaped workpiece made of a metal material, extends from the rotation shaft 16 toward the front side X1 , and is rotatably provided on one side a and the other side b around the rotation shaft 16 .

[0034] Connecting rod 17 Figure 2 In the initial state shown, the connecting rod 17 is urged toward the other side b by the force of the switching member 50 described later, and extends obliquely in a manner that is located on the upper side Z2 as it moves from the rear end supported on the rotating shaft 16 toward the front end. The connecting rod 17 rotates toward one side a around the rotating shaft 16 by receiving an external force. Examples of external forces include forces generated by changes in the pressure of the refrigerant in the above-mentioned refrigeration cycle. Such force is applied to a sensing component (not shown) mounted on the pressure switch, and is transmitted to the connecting rod 17 via the transmission member 118. The receiving portion 18 is formed on the plate surface of the connecting rod 17. As shown Figure 3 As shown, the receiving portion 18 is formed by protruding the middle portion of the plate surface of the link 17 in the front-rear direction X upward, and has a V-shaped cross-section surface opened toward the lower side Z1. The operating shaft 20 whose axis extends in the vertical direction Z is supported by the receiving portion 18.

[0035] The working shaft 20 is a shaft component that converts the rotational motion of the connecting rod 17 into an advance and retreat motion in the up-down direction Z, and acts on the switching member 50 described later by moving in the up-down direction Z. The working shaft 20 can be connected to move forward and backward relative to the box part 10 in the up-down direction Z in a state where it is inserted through the insertion through hole 19 that penetrates the upper wall 14 of the box part 10 in the up-down direction Z. The upper end of the working shaft 20 constitutes a pressed portion 21 pressed by the connecting rod 17. In the present embodiment, the pressed portion 21 is configured to be slidably connected to the V-shaped inner surface of the receiving portion 18 in the connecting rod 17 and pressed by the lower side Z1. On the other hand, the lower end of the working shaft 20 constitutes an engaging portion 22 engaged with the switching member 50 described later. The working shaft 20 is held by a sealing component 30 that closes the gap between the working shaft 20 and the insertion through hole 19, and is connected to the box part 10. The sealing member 30 is provided to hermetically seal between the working shaft 20 and the insertion through hole 19, and prevent the external atmosphere or foreign matter in the micro switch 1 from invading the accommodation space 11 from between the working shaft 20 and the insertion through hole 19. In addition, when the external atmosphere or foreign matter can be allowed to invading the accommodation space 11, the sealing member 30 may not be provided. That is, the inner diameter of the insertion through hole 19 may be reduced according to the outer diameter of the working shaft 20, and the working shaft 20 may be guided by the insertion through hole 19 of the upper wall 14 of the box portion 10.

[0036] The sealing member 30 is formed into a cylindrical shape by, for example, a flexible resin material. The upper opening edge 31 of the sealing member 30 covers the working shaft 20 in the circumferential direction around the shaft, and the lower opening edge 32 of the sealing member 30 covers the opening edge of the insertion through hole 19, thereby, for example, setting the airtightness in the storage space 11 in a manner having an airtightness of at least several tens of kPa from the storage space 11 side. With this structure, even if the pressure response switch 100 is used in a flammable fluid environment, it is possible to prevent the flammable fluid from invading the storage space 11, and prevent the risk of ignition caused by sparks generated by the operation of the micro switch 1. In addition, the setting of the airtightness of the storage space 11 is not limited to the above, and can be arbitrarily set according to the envisioned use environment. For example, when preventing foreign matter from invading the storage space 11 and allowing gas fluid to invading, the airtightness of the storage space 11 can be set to a degree that can prevent foreign matter from invading.

[0037] like Figure 3As shown, a contact 40 is provided in the storage space 11 of the box portion 10. The contact 40 is a conducting component made of a conductive material, and has a pair of fixed contacts 41 fixed in the storage space 11, and a movable contact 44 arranged between the pair of fixed contacts 41. The pair of fixed contacts 41 is composed of a first fixed contact 42 and a second fixed contact 43. The first fixed contact 42 is fixed to the inner wall of the box portion 10 in a state facing the upper side Z2. The second fixed contact 43 is arranged on the upper side Z2 of the first fixed contact 42, and is fixed to the inner wall of the box portion 10 in a state facing the lower side Z1 and facing the first fixed contact 42. The movable contact 44 is fixed to the contact holding portion 72 of the outer spring 70 described later, and can be conductive with the first fixed contact 42 or the second fixed contact 43 by being displaced to the upper side Z2 or the lower side Z1 to abut against the first fixed contact 42 or the second fixed contact 43. In the storage space 11 of the box portion 10 , a switching member 50 for switching the conductive state of the movable contact 44 (contact 40 ) is provided between the operating shaft 20 and the contact 40 .

[0038] The switching member 50 is a part that performs a reverse motion as the working shaft 20 moves, and makes the movable contact 44 conductive with one or the other of the first fixed contact 42 and the second fixed contact 43. Figure 3 As shown, the switching member 50 is, for example, a leaf spring formed by bending a metal plate member, and includes a contact plate 51 fixed to the inner wall of the box portion 10. The contact plate 51 includes: a bent portion 52, which is bent toward the rear side X2 by folding back toward the front side X1 from a position fixed to the inner wall of the box portion 10; a plate-shaped inner spring 60 (working spring), which extends continuously toward the front side X1 toward the center of the bent portion 52 in the left-right direction Y, and extends toward the front-to-back direction X and the left-to-right direction Y (i.e., the cross direction); an outer spring 70 (action spring), which is continuous with the bent portion 52 and surrounds the inner spring 60 to be formed into a plate shape; and a reversing spring 80, which connects the inner spring 60 and the outer spring 70. As shown in FIG. Figure 4 As shown in FIG. 1 , the inner spring 60 includes a wide portion 61 constituting the rear side X2 portion. The wide portion 61 is formed in a substantially rectangular shape in a plan view, and as shown in FIG. Figure 5 As shown, it extends obliquely so as to be located at the upper side Z2 as it goes from the rear side X2 toward the front side X1.

[0039] The wide portion 61 is provided with an engagement hole 62 that penetrates in the vertical direction Z, and the engagement portion 22 of the working shaft 20 is engaged with the engagement hole 62 in a state of being inserted and penetrated toward the lower side Z1. That is, the inner spring 60 is connected to the working shaft 20. As a result, the inner edge of the engagement hole 62 abuts against the outer surface of the working shaft 20, and forms an abutment portion 63. A narrow portion 64 whose dimension in the horizontal direction Y is smaller than that of the wide portion 61 is continuously formed on the front side X1 of the wide portion 61. The narrow portion 64 is formed in a substantially rectangular shape in a plan view, and extends obliquely so as to be located at the upper side Z2 as it moves from the rear side X2 toward the front side X1. A first engagement protrusion 65 that protrudes toward the front side X1 is formed at the central portion in the horizontal direction Y of the front edge of the narrow portion 64. In addition, a hole portion 90 that penetrates in the vertical direction Z (plate thickness direction) is formed at the central portion of the plate surface of the narrow portion 64.

[0040] By forming the hole portion 90, the volume of the narrow width portion 64 is reduced, thereby reducing the rigidity of the inner spring 60. That is, the hole portion 90 constitutes a rigidity reducing member in the present invention. In the present embodiment, the hole portion 90 is formed into a substantially regular triangle shape having an acute angle on the side where the abutment portion 63 is located toward the rear side X2. That is, the dimension of the hole portion 90 in the left-right direction Y increases toward the first connecting portion A. As a result, the volume of the front side X1 portion of the inner spring 60 gradually decreases toward the front side X1 compared to the volume of the rear side X2 portion, and in particular, the rigidity of the inner spring 60 decreases from the side where the abutment portion 63 of the inner spring 60 is located toward the front side X1 where the first connecting portion A (connecting portion) described later is located.

[0041] The outer spring 70 includes a pair of left and right side portions 71 extending continuously with the bent portion 52 toward the front side X1. The side portion 71 on the left side Y1 of the pair of side portions 71 is spaced apart from the end edge of the left side Y1 of the wide portion 61 of the inner spring 60 in the left-right direction Y, and the side portion 71 on the right side Y2 of the pair of side portions 71 is spaced apart from the end edge of the right side Y2 of the wide portion 61 of the inner spring 60 in the left-right direction Y, and each side portion 71 extends toward the front side X1. A contact holding portion 72 is formed at the front end edge of the side portion 71 to connect and extend the side portions 71. The contact holding portion 72 is spaced apart toward the front side X1 of the inner spring 60, and is formed into a plate-like shape whose width dimension in the left-right direction Y decreases as it approaches the front side X1. As shown in FIG. Figure 5As shown, the front end of the contact holding portion 72 is located between the first fixed contact 42 and the second fixed contact 43, and a mounting hole 73 is formed on the front end thereof and penetrates in the vertical direction Z. The movable contact 44 is fixed to the mounting hole 73 in a state of being inserted through. That is, the outer spring 70 holds the movable contact 44. A substantially rectangular plate-shaped protrusion 74 is formed at the rear end edge of the contact holding portion 72 and protrudes toward the inner spring 60. A second engaging protrusion 75 is formed at the center of the rear end edge of the protrusion 74 in the left-right direction Y and protrudes toward the rear side X2, and the second engaging protrusion 75 is opposed to the first engaging protrusion 65 of the inner spring 60 in the front-back direction X.

[0042] like Figure 5 As shown, the reversal spring 80 is formed into a substantially U-shaped opening toward the lower side Z1 by bending a metal plate member, and includes an upper wall surface 81, a rear wall surface 82, and a front wall surface 83. The upper wall surface 81 is formed into a substantially rectangular shape and extends along the front-rear direction X and the left-right direction Y. The rear wall surface 82 is bent toward the lower side Z1 from the rear end edge of the upper wall surface 81, and is inclined in a manner that is slightly located inside as it moves toward the lower side Z1. A first inclined portion 82a is formed at the lower end of the rear wall surface 82 so as to be located outside as it moves toward the lower side Z1. In addition, at the boundary portion of the rear wall surface 82 and the first inclined portion 82a, the front end edge of the narrow width portion 64 of the inner spring 60 abuts against it, and the first engaging protrusion 65 is inserted through it through a through hole not shown in the figure. In this way, the boundary portion of the rear wall surface 82 and the first inclined portion 82a constitutes a first connecting portion A as a connecting portion between the inner spring 60 and the reversal spring 80.

[0043] The front wall surface 83 is bent from the front end edge of the upper wall surface 81 toward the lower side Z1, and is inclined in a manner that is slightly located on the inner side as it moves toward the lower side Z1. A second inclined portion 83a is formed at the lower end of the front wall surface 83, and is inclined in a manner that is slightly located on the outer side as it moves toward the lower side Z1. In addition, at the boundary portion between the front wall surface 83 and the second inclined portion 83a, while abutting against the rear end edge of the protrusion 74 of the outer spring 70, the second engaging protrusion 75 is inserted through this through a through hole not shown. In this way, the boundary portion between the front wall surface 83 and the second inclined portion 83a constitutes the second connecting portion B as the connecting portion between the outer spring 70 and the reversing spring 80. The reversing spring 80 can contract in a direction that brings the first connecting portion A and the second connecting portion B closer together and closes, and can generate a reversing spring load P1 in a direction that moves the first connecting portion A and the second connecting portion B away from each other and opens.

[0044] Next, the operation of the micro switch 1 will be described. Here, as an example of the operation, the micro switch 1 is mounted on a pressure response switch 100 for detecting the pressure of the refrigerant in a refrigeration cycle system, and is used to detect abnormally high pressure. First, in the initial state where the connecting rod 17 does not rotate, as shown in FIG. Figure 5As shown, the movable contact 44 is connected to the first fixed contact 42. At this time, the reversal spring 80 of the switching member 50 is tilted so that the position of the first connection part A is higher than the position of the second connection part B. Due to this tilt, the oblique reversal spring load P1 of the second connection part B and the first connection part A by the reversal spring 80 is converted into a contact load P2 toward the lower side Z1 relative to the outer spring 70. That is, the outer spring 70 applies force to the lower side Z1 and the front side X1 by the reversal spring load P1, and the movable contact 44 is pressed toward the first fixed contact 42 by the contact load P2 toward the lower side Z1.

[0045] From this state, when Figure 1 When the pressure of the refrigerant (i.e., external force) introduced into the element 116 by the joint pipe 117 shown in FIG. 1 suddenly increases, the inductive components such as the bellows or the diaphragm change in the front-to-back direction X according to the pressure change. Then, the change is transmitted to the connecting rod 17 as the operating force via the transmission member 118. The connecting rod 17, which is subjected to the operating force (external force), moves Figure 3 The connecting rod 17 rotates around one side a of the rotating shaft 16 as shown. The rotating motion of the connecting rod 17 is transmitted to the working shaft 20 via the receiving portion 18 and the pressed portion 21, and the working shaft 20 is converted into motion toward the lower side Z1, that is, toward the forward side. Figure 5 As shown by the arrow pointing to the lower side Z1 in FIG. 2 , the operating shaft 20 moves to the lower side Z1 . When the operating shaft 20 moves, the inner spring 60 is deformed along with the movement.

[0046] Specifically, the contact portion 63 of the inner spring 60 is displaced toward the lower side Z1, and with this displacement, the inner spring 60 is deformed toward the lower side Z1 starting from the bent portion 52 in a direction in which the portion of the first connection portion A is located at the lower side Z1 compared to before the deformation. When the inner spring 60 is deformed, the first connection portion A and the second connection portion B are brought closer, thereby causing the reversal spring 80 to deform in a contracted manner. Therefore, the first connection portion A is as Figure 5 As shown by the arrow in FIG. 1 , a force is generated in the rear oblique upward direction (direction located at the upper side Z2 as it moves toward the rear side X2), and the second connecting portion B is as shown in FIG. Figure 5 As shown by the arrow in the figure, an oblique force is generated in the oblique and downward direction (direction located at the lower side Z1 as it moves toward the front side X1). Then, as the working shaft 20 moves, the bias direction of the reversing spring 80 with respect to the outer spring 70 gradually changes toward the front side X1. When the reversing spring 80 reaches the position of Figure 6 When the state shown in (A) is Figure 5 Compared with the initial state shown in FIG. 1 , the inner spring 60 is bent toward the upper side Z2 starting from the vicinity of the hole 90. Figure 5The initial state shown is more gentle than that shown, and the inclination relative to the reversal spring load P1 in the front-rear direction X is maintained. In addition, the contact load P2, which is a component of the reversal spring load P1 in the up-down direction Z, is also maintained accordingly. In addition, as the protrusion 74 side is displaced toward the lower side Z1, the action spring is bent in a manner bent toward the upper side Z2.

[0047] When the working shaft 20 is pushed further toward the lower side Z1 from this state, the force of the inner spring 60 to restore the original shape accumulated by the deflection of the inner spring 60, the force of the reversing spring 80 to restore the original shape accumulated by the deformation of the reversing spring 80, and the force of the outer spring 70 to restore the original shape accumulated by the deflection of the outer spring 70 lose balance, and the contact holding portion 72 of the outer spring 70 suddenly jumps toward the upper side Z2 (reversing action). As a result, the movable contact 44 leaves the first fixed contact 42 and contacts the second fixed contact 43, and the conduction destination of the movable contact 44 is switched. In this state, the reversing spring 80 is tilted in a manner that the position of the first connection part A is lower than the position of the second connection part B, and the direction of the reversing spring 80 applying force to the outer spring 70 is the upper side Z2 and the front side X1. Therefore, the movable contact 44 is pressed toward the second fixed contact 43.

[0048] On the other hand, when the pressure of the refrigerant introduced into the element 116 via the joint pipe 117 decreases from the state where the movable contact 44 and the second fixed contact 43 are in conduction, the connecting rod 17 moves to Figure 3 The other side b around the rotating shaft 16 shown rotates, and the working shaft 20 moves to the upper side Z2, that is, the retreat side. When the working shaft 20 moves to the retreat side, the inner spring 60 is deformed toward the upper side Z2 with the bent portion 52 as the starting point so that the portion of the first connecting portion A is located at the upper side Z2 compared to before the deformation. In addition, the reversing spring 80 is deformed so that the first connecting portion A is displaced toward the upper side Z2. And the outer spring 70 is bent so as to bend toward the lower side Z1. And the force of the inner spring 60 to restore the original shape accumulated by the deflection of the inner spring 60, the force of the reversing spring 80 to restore the original shape accumulated by the deformation of the reversing spring 80, and the force of the outer spring 70 to restore the original shape accumulated by the deflection of the protruding portion 74 of the outer spring 70 lose balance, and the contact holding portion 72 of the outer spring 70 suddenly jumps to the lower side Z1. The second reversing action (reversing action) occurs. As a result, movable contact 44 moves away from second fixed contact 43 and comes into contact with first fixed contact 42 , and the conduction destination of movable contact 44 is switched.

[0049] In addition, in the present embodiment, the position where the reversal action occurs within the moving range of the working shaft 20 is referred to as the reversal position γ. The reversal position γ includes a first reversal position γ1 where the working shaft 20 moving toward the lower side Z1 passes through and generates a first reversal action, and a second reversal position (not shown) where the working shaft 20 moving toward the upper side Z2 passes through and generates a second reversal action. In this structure, after the lower end of the working shaft 20 passes through the first reversal position γ1 toward the lower side Z1, a first reversal action occurs in which the movable contact 44 jumps up to the upper side Z2. On the other hand, after the lower end of the working shaft 20 passes through the second reversal position toward the upper side Z2, a second reversal action occurs in which the movable contact 44 jumps down to the lower side Z1.

[0050] According to this structure, for example, by mounting the micro switch 1 on the pressure response switch 100, a switch can be configured to switch the conduction destination of the movable contact 44 from the first fixed contact 42 to the second fixed contact 43 to cut off the high voltage when abnormal high voltage occurs. And, at this time, the micro switch 1 can be configured as a switch in which the setting value as a trigger for executing the high-voltage cut-off, that is, the first reversal position γ1, and the setting value as a trigger for returning to the original state, that is, the second reversal position, are different positions. However, this is only an example after all, and for example, the first reversal position γ1 and the second reversal position can also be set at the same position, and the number of reversal positions γ can be one. That is, it is also possible to configure a switch in which the setting value as a trigger for executing the high-voltage cut-off, that is, the first reversal position γ1, and the setting value as a trigger for returning to the original state, that is, the second reversal position, are the same position.

[0051] Here, in Figure 6 In the switching member 250 of the conventional micro switch 200 shown in (B), the hole portion 90 is not formed in the inner spring 260 as in the present embodiment, and the rigidity of the inner spring 260 is greater than the rigidity of the inner spring 60 of the present embodiment. Therefore, in a state where the lower end of the working shaft 20 moving toward the lower side Z1 is located at the first reversal position γ1, the inner spring 260 extends in the front-to-back direction X without bending. Therefore, the first connection portion A and the second connection portion B of the reversal spring 80 are located at the same position in the up-down direction Z, and the reversal spring load P1 of the reversal spring 80 is not inclined in the front-to-back direction X. Therefore, the reversal spring load P1 is not converted into the contact load P2 as described above along the direction in which the outer spring 70 extends, and before the first reversal action, the movable contact 44 is not pressed toward the first fixed contact 42. Therefore, when unexpected external forces such as vibration or refrigerant pressure changes are applied to the pressure response switch 100, the movable contact 44 is easily displaced in the up-down direction Z, and a flutter phenomenon of repeated contact and interval relative to the first fixed contact 42 or the second fixed contact 43 is likely to occur.

[0052] In this regard, in the present embodiment, the hole portion 90 is provided in the inner spring 60 as described above, and the rigidity of the inner spring 60 decreases from the side where the abutment portion 63 is located toward the front side X1 where the first connection portion A is located. Figure 6 As shown in (A), when the lower end of the working shaft 20 moving toward the lower side Z1 is located at the first reversal position γ1, the front side X1 portion of the inner spring 60 is bent in a manner of bending toward the upper side Z2 starting from the portion where the hole portion 90 is formed. In this embodiment, the state in which the inner spring 60 is bent and deformed is referred to as the deformed state. Since the inner spring 60 is in the deformed state, the position of the first connection portion A is located at the upper side Z2 compared to the above-mentioned conventional micro switch 200, and the inclination of the reversal spring 80 in which the position of the first connection portion A is higher than the position of the second connection portion B can be maintained until the first reversal action occurs.

[0053] Therefore, the outer spring 70 is urged toward the lower side Z1 and the front side X1 by the reversal spring load P1, and the movable contact 44 is maintained in a state where it is pressed toward the first fixed contact 42 by the contact load P2 toward the lower side Z1. Furthermore, in the present embodiment, in the process where the movable contact 44 leaves the first fixed contact 42 (the second fixed contact 43) and moves toward the second fixed contact 43 (the first fixed contact 42), the first connection portion A and the second connection portion B of the reversal spring 80 are located at the same position in the up-down direction Z. In this way, the reversal spring 80 generates a force that maintains the state where the outer spring 70 presses the movable contact 44 toward the first fixed contact 42 until before the first reversal action occurs. Therefore, even before the first reversal action, the movable contact 44 is maintained in a state where it is pressed toward the first fixed contact 42. Therefore, when an unexpected external force such as vibration or refrigerant pressure change is applied to the pressure responsive switch 100 , chattering phenomenon in which the movable contact 44 repeatedly contacts and separates from the first fixed contact 42 or the second fixed contact 43 is unlikely to occur.

[0054] In addition, the inner spring 60 is also in a deformed state just before the second reversal action occurs. That is, when the lower end of the working shaft 20 moving toward the upper side Z2 is located at the second reversal position, the inner spring 60 is in a deformed state. Thus, the inclination of the reversal spring 80 in which the position of the first connection part A is lower than the position of the second connection part B can be maintained until the second reversal action occurs, and the movable contact 44 is maintained in a state of being pressed toward the second fixed contact 43 until the second reversal action occurs.

[0055] As described above, according to the above embodiment, by providing the hole portion 90 (rigidity reducing member) in the inner spring 60 (working spring), when the working shaft 20 is located at the first reversal position γ1 (reversal position), that is, in a state immediately before the first reversal action (reversal action) is generated, the inner spring 60 can be placed in a deformed state. Furthermore, by placing the inner spring 60 in a deformed state, the reversal spring 80 can generate an acting force that maintains the state in which the outer spring 70 (acting spring) presses the movable contact 44 toward the first fixed contact 42 (fixed contact). Therefore, even before the first reversal action, the state in which the movable contact 44 is pressed toward the first fixed contact 42 can be reliably maintained, and even when an unexpected external force such as vibration or pressure fluctuation is generated, the chattering phenomenon can be suppressed. Therefore, a micro switch 1 that can stably maintain the conductive state of the contact 40 can be provided.

[0056] In addition, according to the present embodiment, by setting a first reversal position γ1 and a second reversal position, the present invention can also be applied to a micro switch 1 of a type in which the first reversal position γ1 (reversal position) that produces a first reversal action (reversal action) in which the conduction destination of the movable contact 44 is switched from the first fixed contact 42 to the second fixed contact 43 is different from the second reversal position (reversal position) in which the conduction destination of the movable contact 44 is switched from the second fixed contact 43 to the first fixed contact 42, and before the reversal action, the movable contact 44 can be maintained in a state of being pressed toward the fixed contact 41.

[0057] In addition, according to the present embodiment, the hole portion 90 reduces the rigidity of the inner spring 60 as it moves toward the side where the first connection portion A (connection portion) is located, and the side where the first connection portion A of the inner spring 60 is located can be deformed more easily than the side where the working axis 20 of the inner spring 60 is located. As a result, the deformed state of the inner spring 60 can be maintained more easily on the side where the first connection portion A is located. Therefore, it is easier to maintain the force of the outer spring 70 against the reversal spring 80 before the reversal action is performed, and the state where the outer spring 70 presses the movable contact 44 toward the fixed contact 41 can be stably maintained. In addition, according to this structure, the rigidity of the side where the working axis 20 of the inner spring 60 is located can be easily increased, so that the durability of the side where the working axis 20 of the inner spring 60 is located can be improved.

[0058] Furthermore, according to the present embodiment, the rigidity reducing member can be provided in the micro switch 1 by a simple method of forming the hole 90 in the inner spring 60 .

[0059] In addition, according to the present embodiment, by increasing the size of the hole 90 in the left-right direction Y toward the first connection portion A, the volume of the inner spring 60 can be reduced toward the first connection portion A and increased toward the abutment portion 63. Therefore, the rigidity of the inner spring 60 can be reduced toward the first connection portion A, and the first connection portion A side of the inner spring 60 can be deformed more easily than the operating shaft 20 side of the inner spring 60. As a result, the deformed state of the inner spring 60 can be maintained more easily on the first connection portion A side.

[0060] Furthermore, according to the present embodiment, the pressure responsive switch 100 can be constructed by mounting the micro switch 1 capable of stably maintaining the conductive state of the contact 40 .

[0061] Next, a modification of the micro switch 1 will be described. Figure 7 : is a plan view showing a part of the switching member 50' in the modified example. In the modified example, the difference from the above embodiment is that the hole portion 90 is not formed in the narrow width portion 64. The two edges of the narrow width portion 64 in the left-right direction Y are formed with a cutout portion 91 that cuts the narrow width portion 64 along the left-right direction Y (width direction). The cutout portion 91 has a tapered shape that is inclined in a manner that it is located on the inner side of the left-right direction Y as it moves toward the rear side X2. By forming the cutout portion 91, the width dimension of the narrow width portion 64 in the left-right direction Y decreases as it moves toward the rear side X2. Through this structure, the rigidity of the inner spring 60 is reduced, especially in the portion on the front side X1 compared to the wide width portion 61. That is, the cutout portion 91 constitutes a rigidity reduction member in the modified example. According to such a modified example, the same effect as the above embodiment can be obtained. In addition, according to this structure, a rigidity reduction member is provided in the micro switch 1 by a simple method of cutting the inner spring 60 to form the cutout portion 91.

[0062] In addition, the above-mentioned embodiment only shows a typical mode of the present invention, and the present invention is not limited thereto. That is, various deformations can be made to implement within the scope of the main purpose of the present invention. Among these deformations, as long as the structure of the micro switch 1 of the present invention is provided, it certainly falls within the scope of the present invention. For example, in the description of the present embodiment, although the micro switch 1 is described as being used to detect abnormally high pressure, the micro switch 1 can also be used when detecting abnormally low pressure on the contrary. In addition, although the connecting rod 17 is inclined in the initial state in a manner that it is located on the upper side Z2 as it moves from the rear end portion supported on the rotating shaft 16 toward the front end portion, on the contrary, the state after rotation in the present embodiment can be used as the initial state of the connecting rod 17, and the other side b of the present embodiment can be used as one side a, and the micro switch 1 can be constructed by adjusting the action direction of the working shaft 20 and the switching member 50 accordingly.

[0063] In addition, in addition to the pressure switch, the micro switch 1 can also be mounted on various switches that rotate when the connecting rod 17 is subjected to a certain external force. For example, although the use of the pressure response switch 100 in this embodiment is mainly described as a pressure switch, the pressure response switch 100 can also be used as a temperature switch. That is, in this embodiment, although the use of the pressure switch is described as an example of introducing the fluid of the detection object (here, the refrigerant circulating in the refrigeration cycle) through the joint pipe 117 and detecting the pressure change by making the pressure of the detection object directly act on the sensing component such as the bellows or the diaphragm, the use of the pressure response switch 100 is not limited to this.

[0064] That is, the temperature-sensitive tube can be connected to the element 116 in the pressure-responsive switch 100 of the present embodiment via a capillary tube, and a temperature switch can be formed by filling a refrigerant inside a closed space formed by the sensing component, the capillary tube, and the temperature-responsive tube. In this way, in the temperature switch using the pressure-responsive switch 100 of the present embodiment, the sensing component is deformed or displaced in the front-to-back direction X according to the pressure inside the closed space that changes based on the temperature change detected by the temperature-responsive tube, and the conduction state of the contact 40 is changed by transmitting the force at this time to the connecting rod 17. In addition, in the present embodiment, a pair of connecting rods 17, a corresponding working shaft 20, a contact 40, a switching member 50, etc. are provided in the micro switch 1, and although a so-called double-type micro switch 1 is formed, the present invention is not limited to the double-type micro switch 1, but can be applied to various micro switches.

[0065] In addition, in the present embodiment, the plate-shaped inner spring 60 is used as the working spring, and the plate-shaped outer spring 70 is used as the action spring. However, the structure of the working spring or the action spring is not limited thereto. For example, the working spring or the action spring may be formed by using a spring member that is not formed into a plate shape.

Claims

1. A micro switch comprising a movable contact disposed between a pair of fixed contacts, an operating shaft moving in an advancing and retreating direction, and a switching member that reverses as the operating shaft moves to connect the movable contact to one or the other of the pair of fixed contacts, wherein the micro switch is characterized in that: The switching member includes an operating spring connected to the operating shaft, an action spring for holding the movable contact, and a reversing spring connecting the operating spring and the action spring. The working spring is configured to be deformable as the working shaft moves. The reversing spring is configured to apply force to the action spring according to the deformation of the working spring. The action spring is configured to be able to be urged by the reversing spring to press the movable contact toward one or the other of the pair of fixed contacts. The moving range of the working axis includes a reversal position where the reversal action occurs after passing through, The working spring is provided with a rigidity reducing member, which is used to be in a flexed deformed state when the working shaft is located at the reverse position. The reversing spring generates an urging force that maintains a state in which the action spring presses the movable contact toward one or the other of the pair of fixed contacts when the actuating spring is in the deformed state.

2. The micro switch according to claim 1, characterized in that: The fixed contact includes a first fixed contact and a second fixed contact arranged on a rearward side of the first fixed contact in the forward and backward direction. The reversal position includes a first reversal position where the reversal action occurs after the working axis passes toward the advancing side in the advancing and retreating direction, and a second reversal position where the reversal action occurs after the working axis passes toward the retreating side. When the working shaft moving toward the forward side is located at the first reversal position, the movable contact is pressed toward the first fixed contact; when the working shaft moving toward the backward side is located at the second reversal position, the movable contact is pressed toward the second fixed contact.

3. The micro switch according to claim 1 or 2, characterized in that: The switching member includes an inner spring as the working spring extending in a direction intersecting the advancing and retreating direction and formed in a plate shape, an outer spring as the action spring surrounding the inner spring and formed in a plate shape, and the reversing spring. The inner spring includes a contact portion that contacts the operating shaft. The rigidity reducing member reduces the rigidity of the inner spring from the side where the abutment portion is located toward the side where the connection portion with the reversal spring is located.

4. The micro switch according to claim 3, characterized in that: The rigidity reducing member is a hole portion penetrating the inner spring in a plate thickness direction.

5. The micro switch according to claim 4, characterized in that: A dimension of the hole portion in a width direction increases toward the connecting portion.

6. The micro switch according to claim 3, characterized in that: The rigidity reducing member is formed of a notch portion formed by notching the inner spring in a width direction.

7. A pressure-responsive switch, characterized in that: A micro switch according to claim 1 is provided.

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