Explosion-proof limit switch

Abstract

The invention 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, mounting brackets are arranged on two sides of the lower shell, fixing bolts are arranged between the mounting brackets and the lower shell, an indicator body is arranged above the upper shell, and the indicator body is arranged above the lower 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 method has the advantage of stable performance.

Description

Technical Field

[0001] The invention relates to the field of switches, in particular to an explosion-proof limit switch. Background Art

[0002] Existing explosion-proof limit switches have problems such as unstable performance and low strength due to factors such as their connection structure and box material. Summary of the invention

[0003] The object of the present invention is to provide an explosion-proof limit switch to solve the problems raised in the above-mentioned background technology, which has the advantage of stable performance.

[0004] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: an explosion-proof limit switch, comprising a shell, the shell comprising an upper shell and a lower shell, a locking bolt is arranged between the upper shell and the lower shell, mounting brackets are arranged on both sides of the lower shell, fixing bolts are arranged between the mounting bracket and the lower shell, an indicator body is arranged above the upper shell, an indicator shield is arranged on the outside of the indicator body, a large flat head screw is arranged between the indicator shield and the upper shell, and a protective O-ring is arranged on one side of the upper shell.

[0005] By adopting the above technical solution, the upper shell and the lower shell are connected together by the locking bolts, and the lower shell is connected to the mounting bracket by the fixing bolts. The indicator shield 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 in the market. The adjustable universal mounting bracket is convenient for customers to adapt to actuators of various specifications;

[0007] The lower shell is made of aluminum alloy / 316. The lower shell can meet the explosion-proof level in hazardous places: Ex db IIC T6Gb Ex tb IIIC T80℃ Db. It contains components that may ignite the explosive gas environment. It can withstand the pressure generated by the explosion of the internal explosive mixture and prevent the explosion from spreading to the explosive gas environment around the shell.

[0008] The upper shell is made of aluminum alloy / 316 upper shell: it can meet the explosion-proof level in hazardous places: Ex db IIC T6 GbEx tb IIIC T80℃ Db. It can contain parts that may ignite the explosive gas environment. It can withstand the pressure generated by the explosion of the internal explosive mixture and prevent the explosion from spreading to the explosive gas environment around the shell.

[0009] The locking bolts are used for high-altitude operations in dangerous areas. When the cover is opened to install the product, the bolts will not loosen and fall off after the cover is opened, and can be firmly fitted on the housing cover;

[0010] Indicator cover: The large flat bottom of CP material can be more effectively connected with the O-ring, greatly improving the sealing performance of the product;

[0011] Cooperate with the indicator cover to lock the cover more effectively.

[0012] As a further solution of the present invention: the outer side of the indicator body is sprayed 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 in green, which can more effectively provide on-site staff with the identification of the valve working status;

[0014] As a further solution of the present invention: a spindle assembly is installed in the shell, the spindle assembly includes a spindle body, the spindle body is sleeved with a circular cam, and a micro switch assembly is installed in the shell and is located on one side of the spindle assembly.

[0015] By adopting the above technical solution, the existing through-type micro switch assembly can cover the mains voltage from low voltage to 250V to adapt to different electrical equipment with different currents, meet the diverse power load requirements, ensure good conductivity, and reduce heat and energy loss;

[0016] Rated current: MAX250VAC / DC to limit energy release;

[0017] Rated current: can be controlled below 16A to ensure that no excessive current occurs in the event of a fault

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

[0019] High precision: after repeated on / off operations, the contacts can still switch at basically the same position, and the position detection error is extremely small;

[0020] Speed: The switching action of the contacts can be completed in an instant, regardless of the speed of the transmission element. It can also effectively reduce the wear and oxidation of the contacts, thereby improving the reliability and overall service life of the switch, which can reach more than millions of times;

[0021] The operating environment can reach -60℃

[0022] Intrinsically safe micro switch assembly: can meet the needs of ordinary and intrinsically safe micro switches,

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

[0024] Rated voltage: At 8.2VDC, to limit the release of energy.

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

[0026] Contact resistance: at milliohm level, ensuring good conductivity and reducing energy loss.

[0027] Insulation resistance: above megohm level. To ensure the insulation performance when the switch is disconnected.

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

[0029] The operating environment temperature can reach minus 60℃;

[0030] The circular cam is used to cooperate with the main shaft to more effectively contact with the micro switch to form a matching contact. The rotation of the actuator drives the main shaft to cooperate with the micro switch contact to play a great role in remote control.

[0031] As a further solution of the present invention: a potentiometer, a wiring terminal and a PCB circuit board are also arranged in the shell, and a fixing screw is arranged on the wiring terminal.

[0032] By adopting the above technical solution, the potentiometer: the resistance of the potentiometer changes with the rotation angle or sliding position in a linear relationship, and is suitable for circuits that require uniform adjustment, such as general voltage regulation circuits; the gear is driven by the rotation of the main shaft to make the potentiometer resistance change from small to large, or vice versa, to control the resistance value characteristics;

[0033] PCB circuit board:

[0034] Industrial Automation: Seamlessly connect with PLC, DCS and other control systems, because its 5 - 20mA is a standard signal, which is convenient for transmission and processing; long-distance transmission has strong anti-interference and can accurately feedback the status of equipment remotely; it can also finely control the equipment according to the degree of micro switch action, such as welding current adjustment.

[0035] Instruments and meters: Adapt to various instruments and convert their own status into standard analog signals for instruments to receive and process, such as electronic scales and pressure meters. It can also assist in calibration and improve measurement accuracy.

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

[0037] As a further solution of the present invention: an indicator O-ring is arranged between the indicator body and the indicator shield.

[0038] By adopting the above technical solution, the grade of the O-ring is selected to meet the protection grade IP66, and the double O-ring is used to greatly improve the outdoor waterproof performance of the product.

[0039] Compared with the prior art, the present invention has the following beneficial effects:

[0040] It can meet the explosion-proof level of Ex db IIC T6 Gb Ex tb IIIC T80℃ Db in hazardous areas. It can contain components that may ignite explosive gas environment. It can withstand the pressure generated by the explosion of the internal explosive mixture and prevent the explosion from spreading to the explosive gas environment around the shell. It has the advantage of strong stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 It is a structural schematic diagram of an embodiment;

[0042] Figure 2 An exploded schematic diagram of an embodiment;

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

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

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

[0046] Figure 6 for Figure 2 Front view of .

[0047] In the figure: 1. Mounting bracket; 2. Lower housing; 3. Protective O-ring; 4. Micro switch assembly; 5. Potentiometer; 6. Upper housing; 7. Locking bolt; 8. Indicator O-ring; 9. Indicator body; 10. Indicator shield; 11. Large flat head screw; 13. PCB circuit board; 14. Fixing screw; 15. Terminal block; 16. External grounding bolt; 17. Spindle assembly; 18. Fixing bolt. DETAILED DESCRIPTION

[0048] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0049] In the embodiment of the present invention,

[0050] An explosion-proof limit switch, such as Figure 1-Figure 6As shown, it includes a shell, which includes an upper shell 6 and a lower shell 2, a locking bolt 7 is arranged between the upper shell 6 and the lower shell 2, mounting brackets 1 are arranged on both sides of the lower shell 2, fixing bolts 18 are arranged between the mounting bracket 1 and the lower shell 2, an indicator body 9 is arranged above the upper shell 6, an indicator shield 10 is arranged on the outside of the indicator body 9, a large flat head screw 11 is arranged between the indicator shield 10 and the upper shell 6, and a protective O-ring 3 is arranged on one side of the upper shell 6.

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

[0052] A spindle assembly 17 is installed in the housing. The spindle assembly 17 includes a spindle body. A circular cam is sleeved on the spindle body. A micro switch assembly 4 is installed in the housing and is located on one side of the spindle assembly 17 .

[0053] A potentiometer 5 , a wiring terminal 15 and a PCB circuit board 13 are also arranged in the housing, and a fixing screw 14 is arranged on the wiring terminal 15 .

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

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

[0056] Working principle:

[0057] It can meet the explosion-proof level of Ex db IIC T6 Gb Ex tb IIIC T80℃ Db in hazardous areas. It can contain components that may ignite explosive gas environment. It can withstand the pressure generated by the explosion of the internal explosive mixture and prevent the explosion from spreading to the explosive gas environment around the shell. It has the advantage of strong stability.

[0058] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. An explosion-proof limit switch, comprising a housing, wherein the housing comprises an upper housing (6) and a lower housing (2), characterized in that: A locking bolt (7) is arranged between the upper shell (6) and the lower shell (2), mounting brackets (1) are arranged on both sides of the lower shell (2), fixing bolts (18) are arranged between the mounting bracket (1) and the lower shell (2), an indicator body (9) is arranged above the upper shell (6), an indicator shield (10) is arranged on the outer side of the indicator body (9), a large flat head screw (11) is arranged between the indicator shield (10) and the upper shell (6), and a protective O-ring (3) is arranged on one side of the upper shell (6).

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

3. The explosion-proof limit switch according to claim 1, characterized in that: A spindle assembly (17) is installed in the housing, the spindle assembly (17) comprising a spindle body, the spindle body being sleeved with a circular cam, and a micro switch assembly (4) located on one side of the spindle assembly (17) is installed in the housing.

4. The explosion-proof limit switch according to claim 1, characterized in that: A potentiometer (5), a wiring terminal (15) and a PCB circuit board (13) are also arranged in the housing, and a fixing screw (14) is arranged on the wiring terminal (15).

5. The explosion-proof limit switch according to claim 1, characterized in that: An external grounding bolt (16) is provided on the side of the lower shell (2).

6. The explosion-proof limit switch according to claim 1, characterized in that: An indicator O-ring (8) is arranged between the indicator body (9) and the indicator shield (10).

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