Explosion-proof limit switch

Abstract

The utility model discloses an explosion-proof limit switch, which comprises a shell, the shell comprises an upper shell and a lower shell, a locking bolt is arranged between the upper shell and the lower shell, two sides of the lower shell are provided with mounting brackets, and fixing bolts are arranged between the mounting brackets and the lower shell. An indicator body is arranged above the upper shell, an indicator shield is arranged on the outer side of the indicator body, a large flat head screw is arranged between the indicator shield and the upper shell, and a protection O-shaped ring is arranged on one side of the upper shell. The utility model has the advantage of stable performance.

Description

Technical Field

[0001] This utility model relates to the field of switches, specifically an explosion-proof limit switch. Background Technology

[0002] Existing explosion-proof limit switches suffer from problems such as unstable performance and low strength due to factors such as their connection structure and housing materials. Utility Model Content

[0003] The purpose of this utility model is to provide an explosion-proof limit switch to solve the problems mentioned in the background art, which has the advantage of stable performance.

[0004] To achieve the above objectives, this utility model provides the following technical solution: an explosion-proof limit switch, comprising a housing, the housing including an upper housing and a lower housing, a locking bolt provided between the upper housing and the lower housing, mounting brackets provided on both sides of the lower housing, a fixing bolt provided between the mounting brackets and the lower housing, an indicator body provided on the upper housing, an indicator cover provided on the outside of the indicator body, a large flat-head screw provided between the indicator cover and the upper housing, and a protective O-ring provided on one side of the upper housing.

[0005] By adopting the above technical solution, the upper housing and the lower housing are connected together by locking bolts, the lower housing is connected to the mounting bracket by fixing bolts, the indicator cover plays a protective role, and the indicator body plays an indicating role.

[0006] Mounting bracket: Designed according to NAMUR standards to meet the diverse specifications of actuators on the market, the adjustable and universal mounting bracket makes it easy for customers to adapt to various actuator specifications.

[0007] The lower housing is made of aluminum alloy / 316. The lower housing can meet the explosion protection rating of Ex db IIC T6Gb Ex tb IIIC T80℃ Db in hazardous locations. It can contain components that may ignite an explosive gas atmosphere, withstand the pressure generated by the explosion of the internal explosive mixture, and prevent the explosion from propagating to the explosive gas atmosphere around the housing.

[0008] The upper shell is made of aluminum alloy / 316. It can meet the explosion protection level of Ex db IIC T6 Gb Ex tb IIIC T80℃ Db in hazardous locations. It can withstand the pressure generated by the explosion of the internal explosive mixture and prevent the explosion from propagating to the explosive gas environment around the shell.

[0009] Locking bolts are used when working at heights in hazardous areas. When the product is installed after opening the cover, the bolts will not loosen or fall off after the cover is opened, and they can be firmly fitted onto the outer cover.

[0010] Indicator cover: Made of CP material, the large flat bottom more effectively engages with the O-ring seal, greatly improving the product's sealing performance;

[0011] When used in conjunction with the indicator cover, it provides a more effective locking mechanism.

[0012] As a further aspect of this invention, the outer side of the indicator body is coated with dye.

[0013] By adopting the above technical solution, the indicator body is sprayed with red and green dyes and printed with "CLOSED" and "OPEN" (green), which more effectively provides on-site personnel with identification of the valve's working status.

[0014] As a further embodiment of this utility model: a spindle assembly is installed inside the housing, the spindle assembly includes a spindle body, a circular cam is sleeved on the spindle body, and a micro switch assembly located on one side of the spindle assembly is installed inside the housing.

[0015] By adopting the above technical solutions, existing general-purpose micro-switch components can cover mains voltages from low voltage to 250V, adapting to different electrical equipment with varying currents, meeting diverse power load requirements, ensuring good conductivity, and reducing heat generation and energy loss.

[0016] Rated current: MAX 250VAC / DC to limit energy release;

[0017] Rated current: can be controlled below 16A to ensure that excessive current will not occur in the event of a fault.

[0018] Withstand voltage: Able to withstand a certain voltage without breaking down;

[0019] High precision: Even after repeated on / off operations, the contacts can still switch in basically the same position, with minimal position detection error.

[0020] Speed ​​of operation: It can complete the switching action of the contacts in an instant, regardless of the operating speed of the transmission components. It can also effectively reduce the wear and oxidation of the contacts, thereby improving the reliability and overall service life of the switch, with a service life of up to millions of cycles.

[0021] It can operate in environments as low as -60°C.

[0022] Intrinsically safe micro switch components: These can meet the requirements of both general-purpose and intrinsically safe micro switches.

[0023] Intrinsically safe microswitches are mainly used in hazardous environments and have higher safety performance.

[0024] Rated voltage: 8.2VDC to limit energy release.

[0025] Rated current: ≤0.1A, ensuring that no excessive current is generated in the event of a fault.

[0026] Contact resistance: in the milliohm range, ensuring good conductivity and reducing energy loss.

[0027] Insulation resistance: above megohms. To ensure insulation performance when the switch is open.

[0028] Withstand voltage: Able to withstand a certain voltage without breaking down;

[0029] The operating ambient temperature can reach as low as -60°C;

[0030] The use of a circular cam in conjunction with the main shaft more effectively forms a contact point with the micro switch. The rotation of the actuator drives the main shaft to engage with the micro switch contact point, which plays a significant role in remote control.

[0031] As a further improvement of this utility model: the housing is also provided with a potentiometer, a terminal block and a PCB circuit board, and the terminal block is provided with a fixing screw.

[0032] By adopting the above technical solution, the potentiometer exhibits a linear relationship between its resistance value and the rotation angle or sliding position, making it suitable for circuits requiring uniform adjustment, such as general voltage regulation circuits. The rotation of the main shaft drives the gears to control the resistance value by changing from small to large or vice versa.

[0033] PCB circuit board:

[0034] Industrial Automation: Seamlessly integrates with control systems such as PLC and DCS. Its 5-20mA signal is standard, facilitating transmission and processing. It has strong anti-interference capabilities for long-distance transmission and can provide accurate remote feedback on equipment status. It can also finely control equipment based on the degree of micro-switch operation, such as adjusting welding current.

[0035] Instrumentation: It is compatible with various instruments and converts its own status into standard analog signals for instruments to receive and process, such as electronic scales and pressure gauges. It can also assist in calibration and improve measurement accuracy.

[0036] Preferably, an external grounding wire bolt is provided on the side of the lower housing.

[0037] As a further improvement of this utility model, an indicator O-ring is provided between the indicator body and the indicator cover.

[0038] By adopting the above technical solutions, the O-rings are selected to meet the IP66 protection level, and the use of double O-rings significantly improves the outdoor waterproof performance of the product.

[0039] Compared with the prior art, the beneficial effects of this utility model are:

[0040] It can meet the explosion protection rating of Ex db IIC T6 Gb Ex tb IIIC T80℃ Db for components that may ignite an explosive gas atmosphere. It can withstand the pressure generated by the explosion of the internal explosive mixture and prevent the explosion from propagating to the explosive gas atmosphere around the enclosure. It has the advantage of high stability. Attached Figure Description

[0041] Figure 1 This is a schematic diagram of the structure of an embodiment;

[0042] Figure 2 This is an exploded view diagram of an embodiment;

[0043] Figure 3 This is a side view of an embodiment;

[0044] Figure 4 A top view of the embodiment with a portion of the housing removed;

[0045] Figure 5 for Figure 4 A schematic diagram of the structure;

[0046] Figure 6 for Figure 2 The front view.

[0047] In the diagram: 1. Mounting bracket; 2. Lower housing; 3. Protective O-ring; 4. Microswitch assembly; 5. Potentiometer; 6. Upper housing; 7. Locking bolt; 8. Indicator O-ring; 9. Indicator body; 10. Indicator cover; 11. Flat head screw; 13. PCB circuit board; 14. Fixing screw; 15. Terminal block; 16. External grounding bolt; 17. Spindle assembly; 18. Fixing bolt. Detailed Implementation

[0048] The technical solutions in the embodiments of this utility model are described clearly and completely below. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0049] In this embodiment of the utility model,

[0050] An explosion-proof limit switch, such as Figures 1-6 As shown, the device includes a housing, which comprises an upper housing 6 and a lower housing 2. A locking bolt 7 is provided between the upper housing 6 and the lower housing 2. Mounting brackets 1 are provided on both sides of the lower housing 2. Fixing bolts 18 are provided between the mounting brackets 1 and the lower housing 2. An indicator body 9 is provided on the top of the upper housing 6. An indicator cover 10 is provided on the outside of the indicator body 9. A large flat-head screw 11 is provided between the indicator cover 10 and the upper housing 6. A protective O-ring 3 is provided on one side of the upper housing 6.

[0051] The outer side of the indicator body 9 is coated with dye.

[0052] A spindle assembly 17 is installed inside the housing. The spindle assembly 17 includes a spindle body, which is fitted with a circular cam. A micro switch assembly 4 is installed inside the housing on one side of the spindle assembly 17.

[0053] The housing also contains a potentiometer 5, a terminal block 15, and a PCB circuit board 13, with a fixing screw 14 on the terminal block 15.

[0054] An external grounding bolt 16 is provided on the side of the lower housing 2.

[0055] An indicator O-ring 8 is provided between the indicator body 9 and the indicator cover 10.

[0056] Working principle:

[0057] It can meet the explosion protection rating of Ex db IIC T6 Gb Ex tb IIIC T80℃ Db for components that may ignite an explosive gas atmosphere. It can withstand the pressure generated by the explosion of the internal explosive mixture and prevent the explosion from propagating to the explosive gas atmosphere around the enclosure. It has the advantage of high stability.

[0058] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and the inventive concept of the present utility model, should be included within the protection scope of the present utility model.

Claims

1. An explosion-proof limit switch comprising a housing, said housing comprising an upper housing (6) and a lower housing (2), characterized in that: Locking bolts (7) are arranged between the upper shell (6) and the lower shell (2), mounting brackets (1) are arranged on both sides of the lower shell (2), fixed bolts (18) are arranged between the mounting brackets (1) and the lower shell (2), an indicator body (9) is arranged above the upper shell (6), an indicator shroud (10) is arranged on the outer side of the indicator body (9), large flat head screws (11) are arranged between the indicator shroud (10) and the upper shell (6), and a protective 0-shaped ring (3) is arranged on one side of the upper shell (6).

2. The explosion-proof limit switch of claim 1, wherein: The outer side of the indicator body (9) is sprayed with dye.

3. The explosion-proof limit switch of claim 1, wherein: A main shaft assembly (17) is arranged in the shell, the main shaft assembly (17) comprises a main shaft body, a circular cam is sleeved on the main shaft body, and a micro switch assembly (4) is arranged on one side of the main shaft assembly (17) in the shell.

4. The explosion-proof limit switch of claim 1, wherein: A potentiometer (5), a wiring terminal (15) and a PCB circuit board (13) are further arranged in the shell, and fixed screws (14) are arranged on the wiring terminal (15).

5. The explosion-proof limit switch of claim 1, wherein: An external grounding bolt (16) is arranged on the side of the lower shell (2).

6. The explosion-proof limit switch of claim 1, wherein: An indicator 0-shaped ring (8) is arranged between the indicator body (9) and the indicator shroud (10).

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