A pressure switch

Abstract

The present application belongs to the field of switch devices operated by the change of fluid pressure, and particularly relates to a pressure switch. The pressure switch comprises a shell, two terminals fixed relative to the shell, and a diaphragm arranged in the shell. The diaphragm comprises a diaphragm and a conductive layer arranged on the surface of the diaphragm. The conductive layer comprises a contact part corresponding to the two terminals respectively for contact conduction, and a split part connected between the two contact parts and used for splitting when the diaphragm is deformed by the change of fluid pressure. The shell has a communication hole corresponding to the split part and used for communicating with the fluid. The two terminals have an on state kept on by the conductive layer when the fluid pressure is in a normal state, and also have an off state kept off by the split part splitting when the fluid pressure changes. At the moment when the pressure exceeds the pressure bearing by the diaphragm, the diaphragm is deformed, the conductive layer splits and cannot be restored, so that the switch timely and continuously feeds back the pressure change state to the outside.

Description

TECHNICAL FIELD

[0001] The present application relates to a pressure switch, belonging to the field of switch devices operated by the change of fluid pressure. BACKGROUND

[0002] In the industrial process control equipment, in order to ensure that the fluid pressure in the pipeline or fluid storage device does not exceed the safety set value, a safety device containing a pressure switch is usually installed on the equipment to monitor and alarm the leakage of the equipment, so as to ensure the safety of the equipment and the operating environment.

[0003] In the existing pressure switch, such as the air pressure switch (i.e. pressure switch) disclosed in the Chinese Utility Model Patent with the publication number CN2914307Y and the publication date of 2007.06.20, the air pressure switch comprises a switch box and a connector connected together, a diaphragm is arranged between the switch box and the connector, and the inner end face of the switch box is pressed on the edge of the diaphragm. An insulating diaphragm seat is arranged above the diaphragm in the switch box, and a butterfly-shaped elastic diaphragm capable of being touched by the diaphragm is arranged in the diaphragm seat. A guide cooperating top rod is arranged at the center position of the diaphragm seat, the butterfly-shaped elastic diaphragm is contacted by the top rod below, and a reed is contacted by the top rod above. The two ends of the reed are respectively riveted with a moving contact and a terminal post, a static contact is arranged below the moving contact and the moving and static contacts are in a contact closed state, another terminal post is riveted with the static contact, and the terminal posts are tightly connected with the switch box and are respectively connected with wires.

[0004] However, in the scene of instantaneous pressure impact, the pressure is suddenly increased to make the butterfly-shaped elastic diaphragm suddenly turn over and push the top rod to jump upward, so as to separate the moving and static contacts, cut off the circuit and feedback to the outside instantaneously. However, the pressure will be restored instantaneously, the butterfly-shaped elastic diaphragm is reset instantaneously, so as to restore the circuit to be connected and stop the feedback of the pressure change state to the outside, so that the alarm time is very short. If the external circuit connected with the pressure switch fails, but the pressure switch has been restored to the initial state after the circuit is repaired, or the inspection personnel do not notice the alarm, the pressure change information will be missed, which may affect the safety of the control equipment. Therefore, it is necessary to design a pressure switch capable of detecting the pressure change signal in the scene of instantaneous pressure impact and maintaining the pressure change state to continuously feedback the signal. SUMMARY

[0005] The purpose of the present application is to provide a pressure switch to solve the problem that the existing pressure switch cannot maintain the change state of the instantaneous impact pressure and continuously feedback the pressure change signal to the outside.

[0006] To achieve the above object, the pressure switch in the application adopts the following technical scheme:

[0007] A pressure switch comprises a shell, two terminal posts fixedly arranged relative to the shell, and a diaphragm member arranged in the shell, the diaphragm member comprising a diaphragm and a conductive layer arranged on the surface of the diaphragm, the conductive layer comprising contact portions corresponding to the two terminal posts respectively and a breaking portion connected between the two contact portions and used for breaking when the diaphragm is deformed due to fluid pressure change, the shell having a communication hole corresponding to the breaking portion and used for communicating with the fluid, and the two terminal posts having an on state kept by the conductive layer when the fluid pressure is in a normal state and an off state kept by the breaking portion breaking when the fluid pressure changes.

[0008] The above technical scheme has the following beneficial effects: The application belongs to an opening invention. The pressure switch comprises two terminal posts fixedly arranged relative to the shell, and a diaphragm member arranged in the shell, the diaphragm member comprising a diaphragm and a conductive layer arranged on the surface of the diaphragm, the conductive layer comprising contact portions corresponding to the two terminal posts respectively, so that the two terminal posts can be in an on state through the conductive layer, the conductive layer further comprising a breaking portion connected between the two contact portions and used for breaking when the diaphragm is deformed due to fluid pressure change, and the shell having a communication hole corresponding to the breaking portion and used for communicating with the fluid, so that the fluid can act on the diaphragm member, and when the fluid pressure makes the breaking portion break, the two terminal posts break and the circuit is cut off. In use, when the fluid pressure is in a normal state, the two terminal posts are in an on state under the action of the conductive layer, and when the fluid pressure changes instantaneously and exceeds the bearing capacity of the diaphragm member, the diaphragm elastically deforms to make the conductive layer break, so that the two terminal posts break immediately, the pressure change state is fed back to the outside in time through a switch signal, and the conductive layer cannot automatically restore connection, so that the pressure switch can keep the current pressure state and continuously feed back the pressure change signal to the outside.

[0009] Further, the shell is provided with a first insulating gasket for pressing the diaphragm member, and the first insulating gasket is provided with positioning holes for the two terminal posts to pass through to position the terminal posts.

[0010] Further, the first insulating gasket comprises a sleeve and an outward turning edge arranged at one end of the sleeve, the positioning holes are arranged on the outward turning edge, and the sleeve is filled with sealing glue outside the sleeve for fixing the terminal posts.

[0011] Further, the shell is connected with a fixing ring for pressing the outward turning edge, the sleeve passes through the inner hole of the fixing ring, an annular space is formed between the sleeve and the fixing ring, the terminal posts pass through the annular space, and the sealing glue is filled in the annular space.

[0012] Further, the fixing ring is provided with external threads, and the shell is provided with internal threads, and the fixing ring is connected with the shell through the cooperation of the external threads and the internal threads.

[0013] Further, the shell is provided with a second insulating pad, the diaphragm is clamped between the first insulating pad and the second insulating pad, the end surface of the terminal is in contact with the corresponding contact part of the conductive layer, and the second insulating pad is provided with a center hole in communication with the communication hole.

[0014] Further, the diaphragm comprises a circular body and protruding parts protruding from both ends of the circular body in the radial direction, the shell is provided with a mounting hole matched with the shape of the diaphragm, and the two contact parts are arranged on the same radial direction corresponding to the two protruding parts.

[0015] Further, the split part is in the shape of a strip, and a narrowed section with a smaller width than other sections is arranged at the middle of the split part in the length direction.

[0016] Further, the split part extends in a straight line.

[0017] Further, the split part extends in an S-shaped curve. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 It is a front view of the pressure switch of embodiment 1 of the present application.

[0019] Figure 2 It is a top view of the pressure switch of embodiment 1 of the present application.

[0020] Figure 3 It is a structure diagram of the diaphragm of embodiment 1 of the present application.

[0021] Figure 4 It is a structure diagram of the diaphragm of embodiment 2 of the present application.

[0022] In the figure: 1, shell; 11, communication hole; 2, fixing ring; 3, first insulating pad; 31, sleeve; 32, turned edge; 4, diaphragm; 41, diaphragm; 42, conductive layer; 421, split part; 422, contact part; 5, second insulating pad; 6, terminal; 7, sealing glue. DETAILED DESCRIPTION

[0023] The features and performances of the present application are described in further detail below in combination with embodiments.

[0024] In view of the technical problems existing in the prior art, the basic technical idea of the present application is that the pressure switch comprises a shell, two terminals fixed to the shell respectively, a diaphragm arranged in the shell, the diaphragm comprising a diaphragm and a conductive layer arranged on the diaphragm, the conductive layer comprising a contact portion corresponding to the two terminals respectively and a breaking portion connected between the two contact portions and used for breaking when the diaphragm is deformed by fluid pressure change, and a communication hole corresponding to the breaking portion and used for communicating with the fluid is arranged on the shell. Thus, when the fluid pressure is in a normal state, the two terminals are in an on state under the action of the conductive layer; when the fluid pressure changes instantaneously and exceeds the bearing pressure of the diaphragm, the diaphragm will be elastically deformed, the breaking portion of the conductive layer is quickly disconnected, the two terminals are instantaneously disconnected, the pressure switch can feedback the pressure change state to the outside in time, and the conductive layer will not restore the communication, so that the pressure switch is not affected by the external detection conditions and continuously feedbacks the pressure signal to the outside.

[0025] Embodiment 1 of the pressure switch in the present application:

[0026] As shown in Figure 1 , the pressure switch comprises a shell 1, and the material of the shell 1 can be galvanized steel, stainless steel, brass or the like. The outer surface of the shell 1 is provided with external threads for connecting with external equipment, and the end of the shell 1 provided with the external threads is the lower end. The shell 1 is provided with a three-stage stepped hole, and the small-diameter hole, the medium-diameter hole and the large-diameter hole are arranged from bottom to top, and the lower stepped surface is formed between the small-diameter hole and the medium-diameter hole, and the upper stepped surface is formed between the medium-diameter hole and the large-diameter hole. The small-diameter hole is used as the communication hole 11 of the shell 1, and the communication hole 11 communicates with the external monitoring fluid to detect the pressure change state.

[0027] As shown in Figure 1 and Figure 2 , the pressure switch comprises two terminals 6 fixed to the shell 1, which are used for connecting the external circuit to feedback the pressure signal. As shown in Figures 1-3 , the shell 1 is further provided with a diaphragm 4, and the diaphragm 4 is arranged in the medium-diameter hole, and the two terminals 6 are arranged above the diaphragm 4 and contact the diaphragm 4 respectively.

[0028] As shown in Figure 3As shown, the diaphragm member 4 comprises a diaphragm 41 and an electrically conductive layer 42 arranged on the surface of the diaphragm 41, which is located on the upper surface of the diaphragm 41. In production, the diaphragm 41 can be made of polyimide, fluororubber, butadiene-acrylonitrile rubber, etc., and the electrically conductive layer 42 can be made of copper, aluminum, silver, etc., which can be formed on the surface of the diaphragm 41 by means such as photoetching, magnetron sputtering, printed circuit, etc. The diaphragm 41 comprises a circular body and protruding portions protruding from the two ends of the circular body in the radial direction, and the inner wall of the middle hole of the shell 1 is provided with mounting holes (not shown in the figure) corresponding to the shapes of the protruding portions of the diaphragm 41 at the corresponding positions, which are all grooves and extend upward and downward to accommodate the protruding portions of the diaphragm 41, so as to prevent the diaphragm 41 from rotating relative to the shell 1.

[0029] The electrically conductive layer 42 comprises contact portions 422 corresponding to the two terminal posts 6 respectively and a breaking portion 421 connected between the contact portions 422 and used to break when the diaphragm 41 deforms due to the change of fluid pressure. The contact portions 422 are arranged at the two ends of the electrically conductive layer 42, each of which is circular and arranged on the same radial direction corresponding to the two protruding portions, and the part of the contact portion 422 close to the protruding portion of the diaphragm 41 on the corresponding side protrudes from the circular body portion of the diaphragm 41 and is located in the protruding portion of the diaphragm 41. The breaking portion 421 is in the shape of a strip, and a narrowed section with a smaller width than other sections is arranged at the middle of the length direction of the breaking portion 421. In this embodiment, the breaking portion 421 extends in a straight line. The breaking portion 421 corresponds to the communication hole 11, and when the diaphragm 41 deforms due to the change of fluid pressure, the breaking portion 421 can break quickly, so that the two terminal posts 6 are disconnected quickly. Thus, when the fluid pressure in the communication hole 11 is normal, the two terminal posts 6 are in a connected state under the action of the electrically conductive layer 42; when the fluid pressure in the communication hole 11 changes instantaneously and exceeds the bearing capacity of the diaphragm member, the diaphragm 41 will elastically deform, and then the breaking portion 421 of the electrically conductive layer 42 will break quickly from the narrowed section, and the electrically conductive layer 42 cannot automatically restore the connection, so that the two terminal posts 6 are disconnected immediately and remain in a disconnected state, and then the pressure switch can detect the pressure change state in time and maintain the pressure change signal to feedback to the outside continuously.

[0030] As Figure 1As shown, a first insulating gasket 3 is also provided inside the shell 1. The first insulating gasket 3 can be made of insulating materials such as polytetrafluoroethylene, phenolic resin, etc. to ensure the insulation effect between the terminal 6 and the shell 1, and to allow communication only through the conductive layer 42. The first insulating gasket 3 is located above the diaphragm 4 and is used to press the diaphragm 4 to ensure that the diaphragm 4 does not move or rotate relative to the shell 1. The first insulating gasket 3 is provided with positioning holes (not marked in the figure) for the two terminal 6 to pass through respectively, so as to position the terminal 6 and facilitate the installation of the terminal 6. In this embodiment, the first insulating gasket 3 includes a sleeve 31 and an outward-turned edge 32 provided at one end of the sleeve. The positioning hole is provided on the outward-turned edge 32. The outer space of the sleeve 31 is filled with a sealant 7 for fixing the terminal 6, so that the terminal 6 is relatively fixed to the shell 1, and the first insulating gasket 3 is fixed to the terminal 6 together to ensure the stability of the terminal 6 when in use, as well as the insulation performance between the terminal 6 and the shell 1. The outward-turned edge 32 is located in the middle-diameter hole, and lugs with the same shape as the protrusions are provided at positions corresponding to the outward-turned edge 32 and the protrusions of the diaphragm 41, and the lugs are respectively located in the mounting holes on the inner walls of the corresponding middle-diameter holes, so that the first insulating gasket 3 will not rotate relative to the shell 1.

[0031] like Figure 1 As shown, in this embodiment, a second insulating gasket 5 is provided below the diaphragm 4. The diaphragm 4 is sandwiched between the first insulating gasket 3 and the second insulating gasket 5 to further ensure the fixing effect of the diaphragm 4. The second insulating gasket 5 can be made of insulating materials such as polytetrafluoroethylene and phenolic resin to ensure that the terminal 6 is connected only through the conductive layer 42, so that the pressure switch can achieve the designed effect. The second insulating gasket 5 is located in the medium-diameter hole. The bottom surface of the second insulating gasket 5 contacts the lower step surface formed between the small-diameter hole and the medium-diameter hole. The top of the second insulating gasket 5 contacts the bottom of the diaphragm 41, which can protect the diaphragm 4 and prevent the housing 1 from causing wear on the diaphragm 41. A central hole (not shown in the figure) is provided in the center of the second insulating gasket 5, which is connected to the connecting hole 11 for fluid to pass through. The aperture of the central hole is equal to the aperture of the connecting hole 11 to avoid affecting the fluid pressure in the connecting hole 11.

[0032] A retaining ring 2 is also provided within the housing 1, the top of which is flush with the top of the housing 1. The retaining ring 2 is located within the large-diameter hole within the housing 1 and is used to compress the outward-turned edge 32. After the retaining ring 2 is installed, the top of the retaining ring 2 is flush with the top of the housing 1, and the bottom of the retaining ring 2 is pressed against the top of the outward-turned edge 32 of the first insulating gasket 3. The top of the sleeve 31 of the first insulating gasket 3 is flush with the top of the housing 1. At this point, the retaining ring 2 can compress the first insulating gasket 3, diaphragm 4, second insulating gasket 5, and terminal 2 together and secure them relative to the housing 1.

[0033] The fixed ring 2 is screwed with the shell 1, the fixed ring 2 is provided with external thread, the shell 1 is provided with matching internal thread, the internal thread is located on the inner wall of the large diameter hole, the upper end of the fixed ring 2 is provided with an operating hole (not shown in the figure) for the operation tool to screw. The sleeve 31 passes through the inner hole of the fixed ring 2, and the annular space is formed between the sleeve 31 and the fixed ring 2, the terminal post 6 passes through the annular space, and the sealing glue 7 is filled in the annular space. During installation, the second insulating gasket 5, the diaphragm 4, the first insulating gasket 3 and the terminal post 2 are sequentially put into the shell 1, then the fixed ring 2 is screwed into the shell 1 by the operation tool and is tightened, the stability of the positions of the second insulating gasket 5, the diaphragm 4, the first insulating gasket 3 and the terminal post 2 is ensured, so that the stability of the internal structure of the pressure switch is ensured.

[0034] Working principle: The pressure switch can be installed on the external equipment through the external thread, the communication hole 11 in the pressure switch is communicated with the external environment, so the fluid pressure in the communication hole 11 is the same as the external fluid pressure. In use, when the fluid pressure in the communication hole 11 is normal, the two terminal posts 6 are in a communication state under the action of the conductive layer 42; when the fluid pressure in the communication hole 11 changes, especially when the instantaneous impact pressure appears, the fluid pressure exceeds the bearing pressure of the diaphragm 4, the diaphragm 41 is elastically deformed, the conductive layer 42 is quickly broken from the narrow section of the split part 421, so that the terminal post 6 is disconnected, so that the pressure switch detects the pressure change state in time, and the pressure change state is fed back to the outside through the switch signal, and because the conductive layer 42 cannot automatically restore the communication, so the pressure switch will maintain the pressure change state, continuously feed back the signal to the outside, and is not affected by the external detection condition, until the corresponding treatment is performed manually, and a new pressure switch is replaced.

[0035] Embodiment 2 of the pressure switch in the application:

[0036] The difference between this embodiment and embodiment 1 is that, as shown in the figure, Figure 4 The split part 421 extends in an S-shaped curve, and other structures and working principles are the same as those of embodiment 1.

[0037] In other embodiments, when the shape of the split part of the conductive layer is set, the narrow section can not be set, at this time, the width of the split part in the length direction is consistent.

[0038] In other embodiments, when the shape of the diaphragm is set, the diaphragm can be removed from the two protruding parts, at this time, the diaphragm is circular, and the side edge of the diaphragm is in contact with the corresponding inner wall of the shell, at this time, the mounting hole is no longer arranged in the shell, and the lug is no longer arranged on the outer turning edge of the first insulating gasket.

[0039] In other embodiments, the second insulating gasket can not be provided, the side of the diaphragm provided with the conductive layer is the upper surface, the housing is provided with a three-step hole, from bottom to top, the hole is sequentially provided with a small-diameter hole, a medium-diameter hole and a large-diameter hole, and the lower surface of the diaphragm directly contacts the stepped surface formed between the small-diameter hole and the medium-diameter hole in the housing.

[0040] In other embodiments, the fixing ring can not be connected with the housing by threads, at this time, neither the fixing ring nor the inner wall of the housing is provided with threads, the fixing ring and the housing can be assembled together in interference, or the fixing ring and the housing can be bonded together by sealant.

[0041] In other embodiments, the fixing ring can not be provided, at this time, the housing also does not need to be provided with internal threads, and the sealant can be filled in the annular space formed between the sleeve of the first insulating gasket and the housing to fix the terminal post.

[0042] In other embodiments, when the shape of the first insulating gasket is provided, the first insulating gasket can be provided as an annular column, at this time, the annular column is provided with a perforation for the corresponding terminal post to penetrate, and the terminal post and the corresponding perforation are interference-fitted or bonded and fixed by sealant, so that the terminal post and the first insulating gasket are fixed, the first insulating gasket and the fixing ring are interference-fitted, or the fixing ring is not provided, the first insulating gasket and the housing are assembled in interference or connected by threads, when connected by threads, the lower part of the first insulating gasket is provided with external threads, the housing is provided with internal threads matched with the external threads, the top of the first insulating gasket is provided with an operation groove for the operation of a screwing tool, and during installation, the first insulating gasket is screwed into the housing and tightened.

[0043] In other embodiments, when the relationship between the first insulating gasket and the terminal post is provided, the first insulating gasket can not be provided with a positioning hole, at this time, the first insulating gasket is provided as an annular column, the terminal post is located outside the annular column, and the sealant is filled between the first insulating gasket and the housing.

[0044] In other embodiments, the first insulating gasket can not be provided, at this time, the annular flange can be provided on the terminal post, and the end cover can be provided on the top of the housing, the end cover is fixedly connected with the housing by screws, the end cover is provided with a perforation for the terminal post to penetrate out, and the inner side wall of the end cover fixes the terminal post relative to the housing by pressing the annular flange, and the terminal post and the diaphragm are pressed tightly together.

[0045] In other embodiments, when the forming method of the conductive layer is provided, the conductive layer can be formed by electroplating.

[0046] Finally, it should be noted that the above description is only the preferred embodiments of the present application, and is not intended to limit the present application. Although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art will appreciate that modifications can be made to the technical solutions described in the foregoing embodiments without departing from the spirit and principle of the present application, or some technical features thereof can be replaced by equivalent features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A pressure switch, characterized in that: The invention comprises a shell, two terminals fixed relative to the shell and a diaphragm member arranged in the shell, the diaphragm member comprises a diaphragm and a conductive layer arranged on the surface of the diaphragm, the conductive layer comprises contact portions corresponding to and conducting with the two terminals respectively and a splitting portion connected between the two contact portions and used to split when the diaphragm is deformed by a change in fluid pressure, the shell has a connecting hole corresponding to the splitting portion and used to communicate with the fluid, the two terminals have a connected state maintained by the conductive layer when the fluid pressure is in a normal state, and also have a disconnected state maintained by the splitting portion when the fluid pressure changes.

2. The pressure switch according to claim 1, characterized in that: A first insulating pad for pressing the diaphragm is arranged in the shell, and positioning holes for two binding posts to pass through respectively so as to position the binding posts are arranged on the first insulating pad.

3. The pressure switch according to claim 2, characterized in that: The first insulating gasket includes a sleeve body and an outward-turned edge arranged at one end of the sleeve body, the positioning hole is arranged on the outward-turned edge, and the outer space of the sleeve body is filled with sealant for fixing the terminal.

4. The pressure switch according to claim 3, characterized in that: The shell is connected with a fixing ring which presses the outward-turned edge. The sleeve passes through the inner hole of the fixing ring. An annular space is formed between the sleeve and the fixing ring. The terminal passes through the annular space. The sealant is filled in the annular space.

5. The pressure switch according to claim 4, characterized in that: The fixing ring is provided with an external thread, and the shell is provided with an internal thread, and the fixing ring is connected with the internal thread through the external thread.

6. The pressure switch according to any one of claims 2 to 5, characterized in that: A second insulating pad is provided in the shell, the diaphragm is sandwiched between the first insulating pad and the second insulating pad, the end face of the terminal is in contact with the corresponding contact portion on the conductive layer, and the second insulating pad is provided with a central hole connected to the connecting hole.

7. The pressure switch according to any one of claims 1 to 5, characterized in that: The diaphragm comprises a circular body and protrusions protruding from both radial ends of the circular body. A mounting hole matching the shape of the diaphragm is provided in the shell. The two contact portions are arranged in the same radial direction corresponding to the two protrusions.

8. The pressure switch according to any one of claims 1 to 5, characterized in that: The split portion is in a strip shape, and a narrowed section with a width smaller than that of other portions is provided at the middle portion of the split portion in the length direction.

9. The pressure switch according to claim 8, characterized in that: The crack portion extends in a straight line.

10. The pressure switch according to claim 8, characterized in that: The split portion extends in an S-shaped curve.

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