JP3226571U - pressure switch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a normally closed type pressure switch capable of obtaining high durability and vibration resistance. A pressure switch includes a fixed contact fixed to a first metal terminal, a movable contact plate fixed to a second metal terminal 123 and pressing the movable contact to the fixed contact in a separable manner, and a movable contact plate in the working chamber. And an actuating portion for moving the movable contact toward and away from the fixed contact in response to a pressure change, and the movable contact plate 126 is formed in a plate shape having a pair of side edges 126d facing each other. With respect to the force receiving portion 126b that receives a force from the operating portion due to time deformation, the space between the pair of side edges 126d is occupied by the forming material, and one end of the movable contact plate 126 is the end of the second metal terminal 123. It is characterized by being fixed to the part by a plurality of caulking parts 127. [Selection diagram] Figure 2

Description

The present invention relates to a pressure switch.

Conventionally, for example, to detect a pressure change of a working fluid in refrigerant pressure detection in a refrigeration cycle of a refrigeration/air-conditioning equipment, hydraulic oil pressure detection of a hydraulic control equipment, intake/exhaust of a vehicle, pressure detection of lubricating oil, etc. A pressure switch is used. As an example of such a pressure switch, there is known a diaphragm-type pressure switch that uses a diaphragm, which undergoes a reverse displacement upon receiving a pressure change, as a pressure-sensitive member (see, for example, Patent Document 1). The pressure switch described in Patent Document 1 has an operating portion that receives a pressure change in the operating chamber that is equal in pressure to the detected portion with a diaphragm. The operating portion is configured to detect the pressure change of the detected portion by bringing the movable contact into and out of contact with the fixed contact according to the pressure change in the operation chamber.

The pressure switch is roughly classified into a normally closed type and a normally open type. The normally closed type is a structure in which the movable contact is in contact with the fixed contact and is in a conductive state (switch ON) until the operation part is operated, and the normally open type is until the operation part is operated. It is a structure in which the movable contact is separated from the fixed contact to be in a non-conductive state (switch OFF). These types of pressure switches are properly used according to the application.

Here, most of the pressure switches are provided with a leaf spring-shaped movable contact plate that supports the movable contact so as to be able to come into contact with and separate from the fixed contact. It may be shared with the normally open type. In commonalization, in the normally open type, when the contact plate is pushed up by the actuating shaft, the fixed contact and the movable contact abut more reliably, and the impact when the fixed contact and the movable contact abut is mitigated. Keeping in mind, a movable contact plate having flexibility is often adopted. When the movable contact and the fixed contact are in contact with each other, the flexible movable contact plate is bent, so that reliable contact can be obtained and the impact at the time of contact is mitigated.

Patent No. 5738260

However, when the above-mentioned flexible movable contact plate is used in a normally closed type pressure switch, the movable contact plate is excessively bent when the movable contact is separated from the fixed contact, and the strength of the movable contact plate is reduced. there is a possibility. Further, when excessive vibration is applied as a disturbance during normal operation when the movable contact is in contact with the fixed contact, the movable contact may be brought into and out of contact with the fixed contact finely to change conduction/non-conduction in the pressure switch. .. As described above, there is room for improvement in terms of durability and vibration resistance when the flexible movable contact plate corresponding to the normally open type is used for the normally closed type pressure switch.

Therefore, an object of the present invention is to provide a normally-closed type pressure switch capable of obtaining high durability and vibration resistance by paying attention to the above room for improvement.

In order to solve the above problems, a pressure switch of the present invention comprises a conductive fixed contact fixed to an end of a first metal terminal and one end fixed to an end of a second metal terminal and fixed to the other end. The movable conductive contact, which is pressed against the fixed contact in a separable manner, and the movable contact plate, which is in the form of a leaf spring, and which receives the first pressure fluctuation in the working chamber, separates the movable contact from the fixed contact. The movable contact plate is deformed as described above to switch the conduction state between the first metal terminal and the second metal terminal to the non-conduction state, and the second pressure fluctuation in the direction opposite to the first pressure fluctuation in the working chamber. And an actuating portion for returning the non-conductive state to the conductive state by returning the movable contact plate so that the movable contact comes into contact with the fixed contact, and the movable contact plates are opposed to each other. A plate-shaped member having side edges of the movable contact, and a portion receiving a force from the actuating portion due to deformation when the movable contact is separated, the pair of side edges are occupied by a forming material, One end of the movable contact plate is fixed to the end portion of the second metal terminal by a plurality of caulking portions.

The above-mentioned pressure switch is a normally-closed type pressure switch in which the movable contact is movably pressed against the fixed contact by the movable contact plate. Further, in this pressure switch, the forming material occupies the space between the pair of side edges in the portion of the movable contact plate that receives the force from the operating portion. As a result, the rigidity of the movable contact plate is increased, and the bending of the movable contact plate when the movable contact is separated from the fixed contact by the operating portion is suppressed. At this time, since the rigidity of the movable contact plate is increased, the stress generated when receiving an operation from the actuating portion tends to concentrate on the fixed portion between the movable contact plate and the second metal terminal. In the above pressure switch, since the movable contact plate is fixed to the second metal terminal by the plurality of swaged portions, the above stress can be dispersed to each of the plurality of swaged portions. That is, in the above-mentioned pressure switch, the durability is enhanced by improving the rigidity of the movable contact plate and distributing the stress by the plurality of caulking portions. Further, due to the improved rigidity of the movable contact plate, the movable contact is strongly pressed against the fixed contact during normal operation, so that vibration resistance is also improved. Thus, according to the above pressure switch, high durability and vibration resistance can be obtained.

Here, one end of the movable contact plate is fixed in a state of being overlapped with the fixed surface at the end portion of the second metal terminal, and the plurality of caulking portions are integrally formed with the fixed surface on the fixed surface. It is preferable that the plurality of pins that are erected upright are fitted into the plurality of through holes formed in one end of the movable contact plate in a one-to-one correspondence, crushed, and crimped.

According to this structure, since the plurality of caulking portions are formed by crushing the plurality of pins that are integrally erected with the fixing surface at the end portion of the second metal terminal, for example, rivet caulking using rivets or the like. Since the number of parts is reduced as compared with, the cost of parts can be suppressed.

Further, it is more preferable that the plurality of pins are formed so as to project by gathering the flesh on the back surface side with respect to the fixing surface at the end portion of the second metal terminal on the fixing surface side.

According to this configuration, a plurality of pins can be obtained by adopting an inexpensive construction method such as press working and collecting the meat on the back surface side on the fixed surface side to form a protrusion, so that the processing cost can be suppressed. ..

According to the normally closed type pressure switch of the present invention, high durability and vibration resistance can be obtained.

It is a sectional view for explaining the composition of the pressure switch concerning one embodiment of the present invention. FIG. 3 is a perspective view showing a second metal terminal and a movable contact plate shown in FIG. 1. It is a perspective view which shows the movable contact plate shown by FIG. FIG. 5 is a perspective view showing a second metal terminal and a movable contact plate shown in FIG. 2 in a back surface shape as seen from a direction of an arrow V11 in FIG. 2.

Hereinafter, a pressure switch according to an embodiment of the present invention will be described with reference to FIGS.

FIG. 1 is a sectional view for explaining the structure of a pressure switch according to an embodiment of the present invention.

The pressure switch 100 is of a normally closed type, and is in a conductive state when the pressure of the detected portion is below a predetermined pressure (normal), and when the pressure of the detected portion exceeds the predetermined pressure. Only non-conducting state. With such a state change, it is possible to detect a change in the pressure of the detected portion. The pressure switch 100 includes a joint 101, a cover portion 102, an operating portion 110, and a micro switch 120.

The joint 101 is a cylindrical portion whose one end is connected to the detected part and the other end is connected to the actuating part 110. By making the working chamber 110a in the actuating part 110 equal to the detected part, The pressure change of the detected part is transmitted to the operating part 110. Although the joint 101 is a tubular portion in this embodiment, the joint 101 is not limited to this example, and is formed by, for example, press work, cutting work, die casting, forging work or the like, which is connected to a pipe through which a fluid to be detected is introduced. It may be a metal-worked member having any desired shape. These metal working members may be joined to a lower cover 113 described later by a process such as brazing or welding.

The cover part 102 is a bottomed tubular part that includes the operating part 110 and the microswitch 120 and connects them to each other. The bottom wall 102a supports the outer peripheral portion of the operating portion 110, and a part of the operating portion 110 and the joint 101 are projected from the central opening 102b. Then, the end of the opening 102c on the upper side in the drawing is crimped to the outer peripheral step of the microswitch 120, thereby connecting the operating unit 110 and the microswitch 120.

The operating section 110 includes an upper cover 111, a diaphragm 112, a lower cover 113, an operating shaft 114, a guide section 115, and an O-ring 116. The upper cover 111, the diaphragm 112, and the lower cover 113 constitute a diaphragm unit 110b having a working chamber 110a between the diaphragm 112 and the lower cover 113. One end of the joint 101 penetrates the center of the lower cover 113 and opens inside the working chamber 110a. Further, in this diaphragm unit 110b, in a normal state, that is, when the pressure in the working chamber 110a is less than a predetermined value, the diaphragm 112 has a shape in which the central portion is recessed inward of the working chamber 110a. There is. Then, when the pressure of the detected portion, that is, the pressure of the working chamber 110a becomes equal to or higher than a predetermined pressure, the diaphragm 112 is inverted and displaced to a shape in which the central portion thereof is convex outside the working chamber 110a. ..

The actuating shaft 114 is a rod-shaped portion that transmits the reverse displacement of the central portion of the diaphragm 112 to the microswitch 120. The lower end of the operating shaft 114 passes through the opening 111a of the upper cover 111 and contacts the center of the upper surface of the diaphragm 112. The guide portion 115 is a portion in which the actuating shaft 114 is inserted into a through hole 115a provided in the central portion, and the actuating shaft 114 is movably held along the axis 100a. The O-ring 116 is provided so as to be sandwiched between the peripheral portion of the upper cover 111, the peripheral portion of the guide portion 115, and the peripheral portion of the lower end of the microswitch 120, and is a portion that ensures watertightness at these peripheral portions.

The micro switch 120 includes a body portion 121, a first metal terminal 122, a second metal terminal 123, a fixed contact 124, a movable contact 125, and a movable contact plate 126. The body part 121 is a tubular part with a lid, and the opening peripheral part on the lower end side is connected to the operating part 110 by the cover part 102 with the O-ring 116 sandwiched between the peripheral part of the upper cover 111. ing. The first metal terminal 122 is a metal portion bent in an L shape, a portion corresponding to the L-shaped vertical bar penetrates the ceiling portion of the body portion 121 and is exposed to the outside, and a portion corresponding to the horizontal bar is the body portion 121. It is provided so that it may be located inside. The second metal terminal 123 is a metal part provided so that one end thereof penetrates the ceiling portion of the body portion 121 and is exposed to the outside, and the other end side is located inside the body portion 121. The fixed contact 124 is a conductive contact portion fixed to an end of the first metal terminal 122, which corresponds to an L-shaped horizontal bar located inside the body 121. The movable contact 125 is a contact portion that is electrically connected to the second metal terminal 123 via the movable contact plate 126 and that can be contacted with and separated from the fixed contact 124. The movable contact plate 126 is a conductive, plate-spring-shaped portion formed by bending a strip-shaped forming material into an L shape, and one end corresponding to an L-shaped vertical bar is an end portion of the second metal terminal 123. The movable contact 125 is fixed to the other end, which is the end of the portion corresponding to the L-shaped horizontal bar. The movable contact plate 126 presses the movable contact 125 against the fixed contact 124 in a separable manner.

In the pressure switch 100, the actuation unit 110 receives the first pressure fluctuation in the actuation chamber 110 a and deforms the movable contact plate 126 so that the movable contact 125 is separated from the fixed contact 124. The first pressure fluctuation referred to here is a pressure fluctuation from a normal pressure in which the central portion of the diaphragm 112 is recessed inward of the working chamber 110a to a pressure equal to or higher than a predetermined pressure at which the diaphragm 112 is reversely displaced. Is. When such a first pressure fluctuation occurs, the diaphragm 112 is reversely displaced and pushes up the actuating shaft 114 toward the movable contact plate 126. The movable contact plate 126 is deformed by the actuating shaft 114 so that the portion corresponding to the L-shaped horizontal bar is pushed up. As a result, the movable contact 125 is separated from the fixed contact 124. Due to this separation, the normal conduction state of the first metal terminal 122 and the second metal terminal 123 is switched to the non-conduction state.

On the other hand, when the second pressure fluctuation in the direction opposite to the first pressure fluctuation occurs in the working chamber 110a, the actuating section 110 receives the second pressure fluctuation so that the movable contact 125 comes into contact with the fixed contact 124. The movable contact plate 126 is repositioned. The second pressure variation referred to here is a pressure reduction variation in which the pressure of the working chamber 110a, which has been increased to reversely displace the diaphragm 112 by the first pressure variation, drops to the normal pressure. When such a second pressure fluctuation occurs, the diaphragm 112 is reversely displaced in the direction opposite to that at the time of pressurization, and the working shaft 114 descends toward the working chamber 110a. As a result, the movable contact plate 126 is restored by its own restoring force, and the movable contact 125 comes into contact with the fixed contact 124. By this contact, the non-conduction state between the first metal terminal 122 and the second metal terminal 123 returns to the conduction state in the normal state.

The pressure switch 100 of the present embodiment is generally configured as described above.

Next, the second metal terminal 123 and the movable contact plate 126 will be described in detail.

2 is a perspective view showing the second metal terminal and the movable contact plate shown in FIG. 1, and FIG. 3 is a perspective view showing the movable contact plate shown in FIG. Further, FIG. 4 is a perspective view showing the second metal terminal and the movable contact plate shown in FIG. 2 in a back surface shape as seen from the direction of arrow V11 in FIG.

The second metal terminal 123 includes a terminal portion 123a exposed from the body portion 121, and a support portion 123b positioned inside the body portion 121 and supporting the movable contact plate 126. The terminal portion 123a and the support portion 123b are each formed in a rectangular plate shape, but the support portion 123b is formed wider than the terminal portion 123a. A pair of concave cutouts 123c is provided at the boundary between the terminal portion 123a and the support portion 123b. In addition, the support portion 123b is provided with a pair of side plate portions 123d which are bent from both side edges thereof and are positioned with the movable contact plate 126 interposed therebetween. The upper shoulder of the side plate portion 123d in the drawing also functions as a stopper that keeps the insertion depth of the second metal terminal 123 constant when the second metal terminal 123 is inserted into the body portion 121.

The movable contact plate 126 is formed by bending an L-shaped rectangular strip-shaped forming material having a pair of side edges 126c facing each other. The portion corresponding to the L-shaped vertical bar is shorter than the portion corresponding to the L-shaped horizontal bar, and this short vertical bar portion becomes the fixed portion 126a fixed to the support portion 123b of the second metal terminal 123. There is. The long horizontal bar portion has a rectangular force receiving portion 126b having the same width as the fixed portion 126a, which is pushed up by receiving force from the operating shaft 114 when the above-described first pressure fluctuation occurs in the operating chamber 110a, And a trapezoidal contact fixing portion 126c to which the movable contact 125 is fixed. The movable contact 125 is crimped and fixed to the contact fixing portion 126c, and the contact fixing portion 126c is provided with a contact through hole 126c-1 for crimping and fixing.

Here, in the present embodiment, the movable contact plate 126 has a pair of opposing sides with respect to the rectangular force receiving portion 126b that receives a force from the operation shaft 114 of the operation unit 110 due to the deformation of the movable contact 125 when the movable contact 125 is separated. The space between the edges 126d is occupied by the forming material. In other words, in the force receiving portion 126b, no defective portion of the forming material such as a hole or a notch is formed between the pair of facing side edges 126d.

Further, in the present embodiment, the fixed portion 126 a that is one end of the movable contact plate 126 is fixed to the support portion 123 b that is the end portion of the second metal terminal 123 by the two caulking portions 127. That is, the fixed portion 126a of the movable contact plate 126 is fixed in a state of being overlapped with the fixed surface 123b-1 of the support portion 123b of the second metal terminal 123. In the two caulking portions 127, two pins, which are erected integrally with the fixed surface 123b-1, are erected on the fixed surface 123b-1, and two through holes 126a-1 formed in the fixed portion 126a. It is fitted in one-to-one with, crushed and crimped. At this time, in the present embodiment, the two pins of the crimp portion 127 are gathered on the fixed surface 123b-1 side on the back surface side of the fixed surface 123b-1 of the support portion 123b of the second metal terminal 123. As a result, the protrusion is formed. As a result, as shown in FIG. 4, two recesses 127a are formed as traces of pin formation, that is, the formation of the caulking portion 127, on the rear surface side with respect to the fixed surface 123b-1. The two caulking portions 127 are arranged in the width direction D11 of the movable contact plate 126.

In the pressure switch 100 of the embodiment described above, the force receiving portion 126b of the strip-shaped movable contact plate 126 is occupied by the forming material between the pair of side edges 126d. As a result, the rigidity of the movable contact plate 126 is increased, and the bending of the movable contact plate 126 when the movable contact 125 is separated from the fixed contact 124 by the operating unit 110 is suppressed. At this time, since the rigidity of the movable contact plate 126 is increased, the stress generated when the movable contact plate 126 is operated by the operating portion 110 tends to concentrate on the fixed portion between the movable contact plate 126 and the second metal terminal 123. .. In the pressure switch 100 described above, since the movable contact plate 126 is fixed to the second metal terminal 123 by the two caulking portions 127, the above stress can be distributed to the two caulking portions 127, respectively. That is, in the above-mentioned pressure switch 100, the durability is improved by improving the rigidity of the movable contact plate 126 and distributing the stress by the two caulking portions 127. In addition, since the movable contact 125 is strongly pressed against the fixed contact 124 during normal operation due to the improved rigidity of the movable contact plate 126, vibration resistance is also improved. Thus, according to the pressure switch 100 described above, high durability and vibration resistance can be obtained.

Here, in the present embodiment, the two caulking portions 127 are configured by crushing the two pins that are erected integrally with the fixed surface 123b-1 of the supporting portion 123b of the second metal terminal 123. According to this configuration, the number of parts is reduced as compared with, for example, rivet tightening using a rivet, so that the parts cost can be suppressed.

In addition, in the present embodiment, the two pins of the two caulking portions 127 are formed in a protruding manner by collecting the meat on the back surface side of the support portion 123b of the second metal terminal 123 on the fixed surface 123b-1 side. It has become one. According to this configuration, by adopting an inexpensive construction method such as press working, the meat on the back surface side is gathered on the fixed surface 123b-1 side to form a protrusion, and two pins are obtained, so that the processing cost is suppressed. be able to.

It should be noted that the embodiment described above merely shows a typical form of the present invention, and the present invention is not limited to this. That is, various modifications can be made without departing from the gist of the present invention. As long as such a modification still has the configuration of the pressure switch of the present invention, it is of course included in the scope of the present invention.

For example, in the above-described embodiment, as an example of the movable contact plate, the force receiving portion 126b that is bent into an L shape as shown in FIGS. 1 to 4 and receives the force from the operating unit 110 has a rectangular shape. The formed movable contact plate 126b is illustrated. However, the movable contact plate is not limited to this, and the specific shape of the part that receives a force from the actuating part is not limited as long as the space between the pair of side edges is occupied by the forming material. Absent. Further, the movable contact plate may be a polygonal plate shape in which each side edge is formed in a polygonal line shape as long as it is formed in a plate shape having a pair of side edges facing each other, or The side edges may be circular, elliptical, fan-shaped, plate-shaped, etc. formed in a curved line shape such as arc shape, and the specific shape is also required in terms of the shape of the pair of side edges. Not a thing.

Further, in the above-described embodiment, as an example of the operating portion, the diaphragm unit 110b having the operating chamber 110a having one end of the joint 101 penetrating the outer wall and opening inside, the operating shaft 114, the guide portion 115, and the O-ring. The actuating part 110 including 116 is illustrated. However, the operating portion is not limited to this, and if the movable contact plate deforms the movable contact plate in response to pressure fluctuations in the operating chamber to bring the movable contact into contact with and separate from the fixed contact, its specific shape is It's not a question.

Further, in the above-described embodiment, as an example of the actuating part, the actuating part that separates the movable contact 125 from the fixed contact 124 due to the pressure change in the working chamber 110a and brings the movable contact 125 into contact with the fixed contact 124 due to the pressure decrease change. 110 is illustrated. However, the operating portion is not limited to this, and contrary to the example, the movable contact is separated from the fixed contact in response to the step-down fluctuation in the working chamber, and the movable contact is brought into contact with the fixed contact in response to the step-up fluctuation. It may be.

Further, in the above-described embodiment, as an example of the pressure switch, the pressure switch 100 in which one end of the movable contact plate 126 is fixed to the end portion of the second metal terminal 123 by the two caulking portions 127 is illustrated. However, the pressure switch is not limited to this, and if a plurality of caulking portions are provided, the specific number thereof does not matter.

Further, in the above-described embodiment, as an example of the caulking portion, the pin integrally erected on the fixed surface 123b-1 of the movable contact plate 126 of the second metal terminal 123 is the through hole 126a- of the movable contact plate 126. A crimping portion 127 that is fitted in 1, crushed and crimped is illustrated. However, the caulking portion is not limited to this, and the caulking mode is not particularly limited as long as the movable contact plate can be fixed to the second metal terminal. However, as described above, the component cost can be suppressed by adopting the crimping portion 127 formed by crushing the pin integrated with the fixing surface 123b-1 of the second metal terminal 123.

Further, in the above-described embodiment, as an example of the caulking portion, the caulking portion 127 formed by crushing a plurality of pins formed by projecting the meat on the back surface side of the second metal terminal 123 is illustrated. ing. However, the caulking portion is not limited to this, and how the formed pin is used can be arbitrarily determined. However, as described above, the processing cost can be suppressed by forming the pin on the caulking portion so as to project using the meat on the back surface side.

100 Pressure Switch 100a Axis 101 Joint 102 Cover Part 110 Actuating Part 120 Micro Switch 121 Body Part 122 First Metal Terminal 123 Second Metal Terminal 123a Terminal Part 123b Support Part 123b-1 Fixed Surface 124 Fixed Contact 125 Movable Contact 126 Moving Contact Plate 126b Force receiving portion 126d Side edge 127 Crimping portion D11 Width direction

Claims (3)

A conductive fixed contact fixed to the end of the first metal terminal;
One end is fixed to the end portion of the second metal terminal, and a conductive movable contact plate fixed to the other end is pressed against the fixed contact in a separable manner.
In response to the first pressure fluctuation in the working chamber, the movable contact plate is deformed so that the movable contact is separated from the fixed contact, and the conduction state between the first metal terminal and the second metal terminal is changed to the non-conduction state. Switching, receiving the second pressure fluctuation in the direction opposite to the first pressure fluctuation in the working chamber, the movable contact plate is returned so that the movable contact comes into contact with the fixed contact, and the non-conduction state is brought into conduction. An operating unit for returning to a state,
The movable contact plate is formed in a plate shape having a pair of side edges facing each other, and a portion that receives a force from the actuating portion for deformation of the movable contact when the movable contact is separated is between the pair of side edges. Is occupied by the forming material,
The pressure switch, wherein one end of the movable contact plate is fixed to an end portion of the second metal terminal by a plurality of caulking portions. One end of the movable contact plate is fixed in a state of being stacked on the fixed surface at the end of the second metal terminal,
In the plurality of swaged portions, a plurality of pins that are provided upright integrally with the fixed surface are fitted into the plurality of through holes formed at one end of the movable contact plate in a one-to-one correspondence with the fixed surface. The pressure switch according to claim 1, which is crushed and crimped. 3. The plurality of pins are formed by projecting by collecting the meat on the back surface side with respect to the fixing surface at the end portion of the second metal terminal on the fixing surface side. Pressure switch shown.

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