Roller type valve limit switch

Abstract

The invention relates to a roller type valve limit switch, which belongs to the field of limit switches and comprises a shell, a roller assembly, a microswitch body and a cable, the microswitch body is fixed in the shell, a contact of the microswitch body penetrates through the shell, a wiring end of the microswitch body is fixedly connected with the cable, and the roller assembly is fixedly connected with the cable. And one end of the roller assembly is fixedly connected with the shell, and one side of the roller assembly extrudes or is far away from the contact, so that the operation reliability of the limit switch is improved.

Description

Technical Field

[0001] The invention relates to the field of limit switches, in particular to a roller type valve limit switch. Background Art

[0002] With the advancement of globalization and the continuous development of industrialization, people's demand for energy is also increasing. The nuclear power industry is developing rapidly, and the requirements for the use of limit switches for nuclear power valve accessories are also increasing. If the limit switch fails during use, it will affect the normal operation of the unit and may even cause shutdown. Therefore, the performance stability and reliability of the limit switch are very important.

[0003] Due to the weak research foundation of nuclear power valve accessories in China, whether in terms of industrial structure or material selection, it is impossible to guarantee the long-term continuous and reliable use of products under high humidity, high heat, high radiation and high vibration environmental conditions. During the use of existing foreign limit switches, under vibration, pressure, impact and other environments, limit switches will also fail, affecting the normal operation of nuclear power plants.

[0004] Therefore, a roller type valve limit switch is provided to solve the problems raised in the above background technology. Summary of the invention

[0005] The technical problem solved by the invention is to improve the reliability of the operation of the limit switch.

[0006] The technical solution of the present invention to solve the above technical problems is as follows: a roller type valve limit switch, comprising a shell, a roller assembly, a micro switch body and a cable, the micro switch body is fixed in the shell, the contact of the micro switch body passes through the shell, the wiring terminal of the micro switch body is fixedly connected to the cable, one end of the roller assembly is fixedly connected to the shell, and one side of the roller assembly squeezes or moves away from the contact.

[0007] The beneficial effect of the present invention is that when the valve switches between opening or closing, the valve switches between squeezing or moving away from the roller assembly, thereby driving the roller assembly to squeeze or move away from the micro switch body, triggering or disconnecting the micro switch body, and then converting the displacement position of the valve opening or closing into a switch quantity electrical signal and transmitting it to the outside, thereby improving the reliability of the limit switch operation. At the same time, it enables the staff to monitor the opening and closing status of the valve in a timely manner.

[0008] Based on the above technical solution, the present invention can also be improved as follows.

[0009] Furthermore, it also includes a baffle assembly, which includes a baffle and a screw. The screw passes through one end of the baffle and one end of the roller assembly in sequence and is fixedly connected to the shell.

[0010] The beneficial effect of adopting the above further scheme is that one end of the baffle in the baffle assembly is fixedly connected to the shell, and the other end of the baffle limits the roller assembly, and then limits the micro switch body, which can prevent the micro switch body from being in an over-travel working state and increase the service life of the limit switch.

[0011] Furthermore, the roller assembly includes a roller, a pressure plate and a spring, the screw passes through one end of the pressure plate and is fixedly connected to the shell, the top of the other end of the pressure plate is rotatably connected to the roller, the bottom of the other end of the pressure plate is fixedly connected to one end of the spring, the other end of the spring is fixedly connected to the shell, and a first protrusion is fixed to one side of the pressure plate, and the first protrusion is squeezed or moved away from the contact.

[0012] The beneficial effect of adopting the above further solution is that the limit switch contacts the valve through the roller, which can reduce friction and improve the environmental adaptability and service life of the limit switch. The pressure plate squeezes the contact of the micro switch body through the first protrusion, which can quickly trigger the micro switch body. After the pressure plate triggers the micro switch body, the spring exerts an upward force on the pressure plate to achieve the rebound of the pressure plate, so as to facilitate the re-triggering action.

[0013] Furthermore, a second protrusion is fixed on the other side of the pressure plate, and the baffle plate is in contact with or separated from the second protrusion.

[0014] The beneficial effect of adopting the above further solution is that the other side of the pressure plate is limited by the second protrusion and the baffle.

[0015] Furthermore, the pressing plate has a first through hole.

[0016] The beneficial effect of adopting the above further solution is that the first through hole on the pressing plate can reduce its own weight.

[0017] Furthermore, the roller and the pressure plate are both surface hardened.

[0018] The beneficial effect of adopting the above further solution is that the surface hardening treatment can improve the wear resistance of the roller and the pressure plate, thereby increasing the service life of the limit switch.

[0019] Furthermore, the spring is a return spring.

[0020] The beneficial effect of adopting the above further scheme is that when the valve and the roller are squeezed, the pressure plate is subjected to a downward force and displaced downward in the vertical direction. At this time, the spring is compressed. Subsequently, after the valve and the roller move away from each other, the pressure plate is reset by the upward force of the spring, thereby increasing the reliability of the limit switch triggering.

[0021] Furthermore, it also includes a plurality of gaskets, which are divided into two groups of gasket groups, one group of the gasket groups is located between one side of the baffle and the other side of the pressure plate, and the other group of the gasket groups is located between one side of the pressure plate and the outer shell, and the screw passes through the baffle, one group of the gasket groups, the pressure plate and the other group of the gasket groups in sequence, and is fixedly connected to the outer shell.

[0022] The beneficial effect of adopting the above further scheme is that the staff increases the number of gaskets in the gasket group between the bottom of one end of the pressure plate and the shell, and then adjusts the position of the pressure plate and the micro switch body, making it easier for the pressure plate to squeeze the micro switch body.

[0023] Furthermore, the cable jacket is provided with a stainless steel metal wire tube, and the stainless steel metal wire tube is fixedly connected to the outer shell.

[0024] The beneficial effect of adopting the above further solution is that the stainless steel metal wire pipe can protect the cable and reduce the aging speed of the cable insulation layer.

[0025] Furthermore, the micro switch body is a SPDT contact air-sealed micro switch.

[0026] The beneficial effect of adopting the above further scheme is that when the valve and the roller are squeezed, the pressure plate is subjected to a downward force, displaces downward and squeezes the contact, thereby triggering the micro switch body, converting the valve position opening or closing displacement signal into a switching electrical signal and transmitting it to the external system. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a structural schematic diagram of the limit switch of the present invention; Figure 2 It is a side view of the limit switch of the present invention; Figure 3 for Figure 2 AA section view; Figure 4 for Figure 3 The enlarged view of point B in the figure; Figure 5 is a structural schematic diagram of a roller assembly; Figure 6 It is a structural schematic diagram of the micro switch body; Figure 7 for Figure 6 CC cross-sectional view.

[0028] In the accompanying drawings, the components represented by the reference numerals are listed as follows: 1. Housing; 2. Baffle assembly; 201. Baffle; 202. Screw; 3. Roller assembly; 301. Roller; 302. Pressure plate; 3021. Second protrusion; 3022. First through hole; 303. Spring; 304. First protrusion; 305. Support plate; 4. Micro switch body; 401. Contact; 402. Terminal; 5. Cable; 6. Gasket; 7. Stainless steel wire tube; 8. Second through hole; 9. Third through hole. DETAILED DESCRIPTION

[0029] The principles and features of the present invention are described below in conjunction with the accompanying drawings. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0030] like Figure 1-Figure 7 As shown, this embodiment provides a roller type valve limit switch, including a shell 1, a roller assembly 3, a micro switch body 4 and a cable 5, the micro switch body 4 is fixed in the shell 1, the contact 401 of the micro switch body 4 passes through the shell 1, the wiring terminal 402 of the micro switch body 4 is fixedly connected to the cable 5, one end of the roller assembly 3 is fixedly connected to the shell 1, and one side of the roller assembly 3 squeezes or moves away from the contact 401.

[0031] When the valve switches between opening or closing, the valve switches between squeezing or moving away from the roller assembly 3, thereby driving the roller assembly 3 to squeeze or move away from the micro switch body 4, triggering or disconnecting the micro switch body 4, and then converting the displacement position of the valve opening or closing into a switch quantity electrical signal and transmitting it to the outside, thereby improving the reliability of the limit switch operation. At the same time, it enables the staff to monitor the opening and closing status of the valve in a timely manner.

[0032] Specifically, when the valve switches between opening and closing, the valve squeezes or moves away from the roller assembly 3 on the housing 1, causing the roller assembly 3 to move up and down in the vertical direction until the micro switch body 4 is squeezed, thereby triggering the micro switch body 4.

[0033] Specifically, the housing 1 has second through holes 8 arranged at intervals, and the housing 1 can be threadedly fixedly connected to the valve mounting frame through the second through holes 8 .

[0034] The size of the housing 1 is smaller than that of the valve, so as to be suitable for valves of smaller size. The housing 1 is made of brass. The bottom of the housing 1 has an electrical interface, and one end of the stainless steel metal wire tube 7 is fixedly connected to the housing 1 through the electrical interface.

[0035] In addition, the housing 1 is provided with a third through hole 9 , and the micro switch body 4 is fixedly connected to the housing 1 via the third through hole 9 .

[0036] Specifically, the connection terminal 402 of the micro switch body 4 and the cable 5 are fixed by epoxy resin encapsulation, which is used to fix the cable 5 and improve the environmental adaptability of the limit switch.

[0037] On the basis of the above scheme, a baffle assembly 2 is further included, and the baffle assembly 2 includes a baffle 201 and a screw 202. The screw 202 passes through one end of the baffle 201 and one end of the roller assembly 3 in sequence, and is fixedly connected to the housing 1.

[0038] One end of the baffle 201 in the baffle assembly 2 is fixedly connected to the housing 1, and the other end of the baffle 201 limits the roller assembly 3, and then limits the micro switch body 4, which can prevent the micro switch body 4 from being in an over-travel working state and improve the service life of the limit switch.

[0039] Specifically, the baffle plate 201 is located above the roller assembly 3. The screw 202 passes through one end of the baffle plate 201 and one end of the roller assembly 3 in sequence and is threadedly connected to the housing 1.

[0040] The baffle 201 may be made of stainless steel.

[0041] On the basis of the above scheme, the roller assembly 3 includes a roller 301, a pressure plate 302 and a spring 303, the screw 202 passes through one end of the pressure plate 302 and is fixedly connected to the housing 1, the top of the other end of the pressure plate 302 is rotatably connected to the roller 301, the bottom of the other end of the pressure plate 302 is fixedly connected to one end of the spring 303, the other end of the spring 303 is fixedly connected to the housing 1, and a first protrusion 304 is fixed on one side of the pressure plate 302, and the first protrusion 304 is squeezed or away from the contact 401.

[0042] The limit switch contacts the valve through the roller 301, which can reduce friction and improve the environmental adaptability and service life of the limit switch. The pressure plate 302 squeezes the contact 401 of the micro switch body 4 through the first protrusion 304, which can quickly trigger the micro switch body 4. After the pressure plate 302 triggers the micro switch body 4, the spring 303 exerts an upward force on the pressure plate 302 to achieve the rebound of the pressure plate 302, so as to facilitate the re-triggering action.

[0043] Specifically, Figure 5 As shown, support plates 305 are provided on both sides of the top of the other end of the pressing plate 302 , and the roller 301 is located between the two support plates 305 and is riveted to the two support plates 305 by pins.

[0044] The baffle 201 is located above the pressing plate 302, and the length of the baffle 201 is smaller than the length of the pressing plate 302. The dimension of the baffle 201 along the width direction is smaller than or equal to the dimension of the pressing plate 302 along the width direction.

[0045] Specifically, the housing 1 has a groove, and the other end of the spring 303 is fixedly connected to the bottom of the groove.

[0046] Specifically, the first protrusion 304 has a circular cross section, and can also be set to a protrusion with a cross section of other shapes according to actual needs, such as a square or rectangular cross section. The spring 303 is used to exert an elastic force on the pressure plate 302 to move it away from the housing 1. The bottom of the other end of the pressure plate 302 can also abut against one end of the spring 303.

[0047] In this embodiment, the first protrusion 304 is located in the middle of the bottom of the pressing plate 302 and corresponds to the position of the contact 401 one by one.

[0048] In addition, one end of the pressing plate 302 has a through hole for the screw 202 to pass through.

[0049] On the basis of the above solution, a second protrusion 3021 is fixed to the other side of the pressing plate 302 , and the baffle 201 is in contact with or separated from the second protrusion 3021 .

[0050] The other side of the pressing plate 302 is limited by the second protrusion 3021 and the baffle 201 .

[0051] Specifically, in this embodiment, the positions of the second protrusions 3021 and the first protrusions 304 are staggered.

[0052] On the basis of the above solution, the pressing plate 302 has a first through hole 3022 .

[0053] The first through hole 3022 on the pressing plate 302 can reduce its own weight.

[0054] Specifically, the first through hole 3022 on the pressing plate 302 can be used to reduce the operating force of the limit switch.

[0055] Based on the above solution, the roller 301 and the pressing plate 302 are both surface hardened.

[0056] The surface hardening treatment can improve the wear resistance of the roller 301 and the pressure plate 302, thereby increasing the service life of the limit switch.

[0057] On the basis of the above solution, the spring 303 is a return spring.

[0058] When the valve and the roller 301 are squeezed, the pressure plate 302 is subjected to a downward force and moves downward in the vertical direction. At this time, the spring 303 is compressed. Subsequently, after the valve and the roller 301 move away from each other, the pressure plate 302 is reset by the upward force of the spring 303, thereby increasing the reliability of the limit switch triggering.

[0059] Specifically, the return spring generates elastic force when being compressed or stretched, which can prevent the pressure plate 302 from being unable to reset due to deformation due to compression, thereby ensuring the long-term working stability of the limit switch.

[0060] On the basis of the above scheme, it also includes a plurality of gaskets 6, and the plurality of gaskets 6 are divided into two groups of gasket groups, wherein one group of the gasket groups is located between one side of the baffle 201 and the other side of the pressure plate 302, and the other group of the gasket groups is located between one side of the pressure plate 30 and the outer shell 1, and the screws 202 pass through the baffle 201, one group of the gasket groups, the pressure plate 302 and the other group of the gasket groups in sequence, and are fixedly connected to the outer shell 1.

[0061] The staff increases the number of gaskets in the gasket group between the bottom of one end of the pressing plate 302 and the housing 1 , and then adjusts the position of the pressing plate 302 and the micro switch body 4 , so that the pressing plate 302 can squeeze the micro switch body 4 .

[0062] Specifically, in this embodiment, the number of gaskets in the gasket group located between the bottom of one end of the baffle 201 and the top of one end of the pressure plate 302 is 3, and the number of gaskets in the gasket group located between the bottom of one end of the pressure plate 302 and the shell 1 is 2.

[0063] The staff can adjust the number of gaskets in the gasket group between the bottom of one end of the pressing plate 302 and the shell 1 according to actual conditions.

[0064] On the basis of the above solution, a stainless steel metal wire tube 7 is disposed on the outer jacket of the cable 5 , and the stainless steel metal wire tube 7 is fixedly connected to the outer shell 1 .

[0065] The stainless steel metal wire tube 7 can protect the cable 5 and reduce the aging speed of the insulation layer of the cable 5 .

[0066] On the basis of the above solution, the micro switch body 4 is a SPDT contact air-sealed micro switch.

[0067] When the valve and roller 301 are squeezed, the pressure plate 302 is subjected to a downward force, moves downward and squeezes the contact 401, thereby triggering the micro switch body 4, converting the valve position opening or closing displacement signal into a switch quantity electrical signal and transmitting it to the external system.

[0068] Specifically, the airtight micro switch body is a sealed structure, which improves the anti-oxidation ability of the contact 401, thereby solving the problem of ablation and oxidation of the traditional limit switch contact.

[0069] Among them, the air-sealed micro switch body has the characteristics of rapid action and sudden displacement change, which can increase the speed of the limit switch connection and disconnection, avoid the problem of false alarm caused by repeated connection and disconnection of the limit switch in a vibration environment due to the small gap between the limit switch contacts.

[0070] In this embodiment, when the valve is switched between open or closed, the valve switches between squeezing or moving away from the roller 301, thereby driving the pressure plate 302 to move up and down in the vertical direction until the first protrusion 304 is squeezed with the contact 401 and the micro switch body 4 is triggered, and the displacement position of the valve opening or closing is converted into a switch electrical signal through the cable 5 and transmitted to the outside, thereby improving the stability of the limit switch operation.

[0071] In the description of the present invention, it should be understood that the terms "center", "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0072] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0073] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0074] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0075] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0076] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A roller type valve limit switch, characterized in that: The invention comprises a housing (1), a roller assembly (3), a micro switch body (4) and a cable (5); the micro switch body (4) is fixed in the housing (1); a contact (401) of the micro switch body (4) passes through the housing (1); a connection terminal (402) of the micro switch body (4) is fixedly connected to the cable (5); one end of the roller assembly (3) is fixedly connected to the housing (1); and one side of the roller assembly (3) presses or moves away from the contact (401).

2. A roller type valve limit switch according to claim 1, characterized in that: It also comprises a baffle assembly (2), the baffle assembly (2) comprising a baffle (201) and a screw (202), the screw (202) sequentially passing through one end of the baffle (201) and one end of the roller assembly (3), and being fixedly connected to the housing (1).

3. A roller type valve limit switch according to claim 2, characterized in that: The roller assembly (3) comprises a roller (301), a pressure plate (302) and a spring (303); the screw (202) passes through one end of the pressure plate (302) and is fixedly connected to the housing (1); the top of the other end of the pressure plate (302) is rotatably connected to the roller (301); the bottom of the other end of the pressure plate (302) is fixedly connected to one end of the spring (303); the other end of the spring (303) is fixedly connected to the housing (1); a first protrusion (304) is fixed to one side of the pressure plate (302); the first protrusion (304) is pressed against or away from the contact (401).

4. A roller type valve limit switch according to claim 3, characterized in that: A second protrusion (3021) is fixed to the other side of the pressure plate (302), and the baffle (201) is in contact with or separated from the second protrusion (3021).

5. A roller type valve limit switch according to claim 3, characterized in that: The pressing plate (302) has a first through hole (3022).

6. A roller type valve limit switch according to claim 3, characterized in that: The roller (301) and the pressing plate (302) are both subjected to surface hardening treatment.

7. A roller type valve limit switch according to claim 3, characterized in that: The spring (303) is a return spring.

8. The roller type valve limit switch according to claim 3, characterized in that: It also includes a plurality of gaskets (6), wherein the plurality of gaskets (6) are divided into two groups of gasket groups, wherein one group of the gasket groups is located between one side of the baffle (201) and the other side of the pressure plate (302), and the other group of the gasket groups is located between one side of the pressure plate (302) and the outer shell (1), and the screw (202) passes through the baffle (201), one group of the gasket groups, the pressure plate (302) and the other group of the gasket groups in sequence, and is fixedly connected to the outer shell (1).

9. A roller type valve limit switch according to any one of claims 1 to 8, characterized in that: The outer jacket of the cable (5) is provided with a stainless steel metal wire tube (7), and the stainless steel metal wire tube (7) is fixedly connected to the outer casing (1).

10. A roller type valve limit switch according to any one of claims 1 to 8, characterized in that: The micro switch body (4) is a SPDT contact air-sealed micro switch.

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