Anti-coaxial offset explosion-proof reversible change-over switch

Abstract

The utility model discloses an explosion-proof reversing change-over switch capable of preventing coaxial offset, which comprises a first shell and a change-over switch arranged in the first shell, two sides of the first shell are provided with limiting parts used for preventing the change-over switch from displacing, a pressing plate is arranged between the two limiting parts, and the first shell is provided with an opening. And the pressing plate is fixedly connected with the limiting part through a screw and is used for fixing the change-over switch. By arranging the limiting part, the switch is effectively prevented from displacement caused by external force, the rotating shaft and the cover plate are ensured to be accurately coaxial, a necessary gap serving as an explosion-proof junction surface between the rotating shaft and the copper sleeve is maintained, and the electrical insulation standard is met; the pressing plate is adopted for pressing installation, the axis of the rotating shaft is prevented from deviating during installation, the offset is further limited, and abnormal abrasion of the copper sleeve and the rotating shaft is prevented.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of explosion -proof change over switch, especially to a kind of explosion -proof reverse conversion switch of preventing coaxial deviation. BACKGROUND

[0002] In the place where there is explosive dangerous gas such as coal mine, chemical plant, the safety of electrical equipment is crucial.To ensure safe operation, explosion-proof control box is often used to control circuit and electric appliance.However, in emergency situations, automatic control system may not meet the demand, at which time the operating personnel need to manually intervene, and the control box is switched between manual / automatic mode.Therefore, explosion-proof control box is usually provided with explosion-proof change over switch for mode conversion.

[0003] The design of the explosion-proof change over switch requires that the handle shaft and the explosion-proof shell maintain precise coaxiality to ensure that the copper sleeve and the shaft maintain a specific gap.This design requirement aims to meet the key electrical insulation standards and explosion-proof requirements, to prevent electrical breakdown or flashover between the shaft and the usually grounded shell under normal operation or potential failure conditions, and to prevent the internal explosive gas mixture from igniting, preventing the internal explosion flame, high-temperature gas or combustion products from escaping through the gap.

[0004] However, during the installation process of the prior art explosion-proof change over switch, as the screw is gradually tightened, the change over switch is deviated, and the shaft of the change over switch is deviated from the axis of the explosion-proof shell.This axial deviation directly leads to an increase in the actual gap between the copper sleeve and the shaft, which exceeds the design standard and cannot meet the electrical insulation standard.In addition, when the axial deviation is too large, the shaft and the copper sleeve will be in direct contact, thereby accelerating the wear of the copper sleeve and the shaft.Therefore, the applicant has made beneficial design and found a method to solve the above problems.The technical solution to be introduced below is generated in this background. SUMMARY

[0005] The utility model discloses a kind of to overcome the deficiencies of the design of the above-mentioned traditional explosion-proof change over switch, and provide a product for ensuring electrical gap and preventing component wear.

[0006] To solve the above problems, the utility model adopts the following technical scheme.

[0007] A kind of explosion -proof reverse conversion switch of preventing coaxial deviation, including first shell body and the change over switch being set in it, the two sides of the first shell body are equipped with the limiting portion for preventing displacement of change over switch, pressure plate is equipped between two limiting portions, the pressure plate is connected and fixed with limiting portion by screw, for fixing change over switch.

[0008] Preferably, the first shell is provided with a wire hole through which the transfer switch wire passes, and the wire hole is glued with epoxy resin.

[0009] Preferably, the second shell is further provided with a connecting plate, both sides of the connecting plate are provided with a plurality of terminal ends, the terminal ends are electrically connected with the terminal ports of the transfer switch, and a partition plate is arranged between adjacent terminal ends.

[0010] Preferably, the second shell is provided with a wire outlet, the wire outlet is provided with a sealing sleeve, the end face of the sealing sleeve is provided with a gasket, the wire outlet is threadedly connected with a compression nut, and the compression nut abuts against the gasket.

[0011] Preferably, the first shell is provided with a cover plate, and the cover plate is provided with a copper sleeve.

[0012] Preferably, the transfer switch is provided with a rotating shaft which passes through the copper sleeve, an explosion-proof joint surface is arranged between the rotating shaft and the copper sleeve, O-shaped sealing rings are arranged at the upper and lower parts of the rotating shaft, and the rotating shaft is provided with a rotating handle.

[0013] Beneficial effects:

[0014] Compared with the prior art, the utility model has the beneficial effects that:

[0015] The utility model discloses a limiting part is arranged, effectively prevents the displacement of transfer switch when being subjected to external force, ensures that the rotating shaft and the cover plate accurately keep on the same axial line, maintains the necessary gap between the rotating shaft and the copper sleeve as the explosion-proof joint surface, thereby meet the relevant electrical insulation standard requirement, in addition, the installation mode that the transfer switch is fixedly installed by the pressing plate avoids the possible axial deviation of the rotating shaft in the installation process, further limits the axial deviation amount, the design effectively prevents the abnormal wear and tear between the copper sleeve and the rotating shaft due to the deviation, and the technical effect that the electrical gap is guaranteed and the component wear and tear are prevented is realized. BRIEF DESCRIPTION OF DRAWINGS

[0016] Fig. 1 It is a top view of the explosion-proof reverse and forward transfer switch of the utility model;

[0017] Fig. 2 It is a side sectional structure schematic diagram of the explosion-proof reverse and forward transfer switch of the utility model;

[0018] Fig. 3 It is a front view of the connecting plate of the explosion-proof reverse and forward transfer switch of the utility model;

[0019] Fig. 4 It is an internal structure top view of the explosion-proof reverse and forward transfer switch of the utility model;

[0020] The correspondence between the reference signs and the component names in the drawings is as follows:

[0021] Reference signs: 1, first shell; 2, change-over switch; 3, pressing plate; 4, screw; 5, second shell; 6, cover plate; 11, limiting part; 12, threading hole; 13, epoxy resin; 21, rotating shaft; 22, explosion-proof joint surface; 23, O-shaped sealing ring; 24, rotating handle; 51, connecting plate; 52, wire outlet; 53, sealing sleeve; 54, gasket; 55, compression nut; 511, terminal; 512, partition plate; 61, copper sleeve. DETAILED DESCRIPTION

[0022] The technical solutions of the present application will be described below in conjunction with the embodiments, obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor belong to the scope of protection of the present application.

[0023] In the description of the present application, it should be understood that the terms "upper", "lower", "left", "right" and the like indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, therefore it cannot be understood as a limitation of the present application.

[0024] In the embodiments of the present application, "and / or" is only a description of the association relationship between the associated objects, which means that there can be three relationships, for example, A and / or B can represent: A alone, A and B exist together, and B alone. In addition, the character " / " in this paper generally represents that the associated objects before and after are a "or" relationship.

[0025] Reference Example Figs. 1 to 4The application discloses an anti-explosion reverse conversion switch capable of preventing coaxial displacement, which comprises a first shell 1, a conversion switch 2 arranged in the first shell 1, limiting portions 11 arranged on two sides of the first shell 1 and used for preventing displacement of the conversion switch 2, a pressing plate 3 arranged between the two limiting portions 11 and used for fixing the conversion switch 2, and a screw 4 used for connecting and fixing the pressing plate 3 and the limiting portions 11. The limiting portions 11 can effectively prevent the conversion switch 2 from being displaced when the conversion switch 2 is subjected to external force, and can ensure that a rotating shaft 21 and a cover plate 6 are accurately kept on the same axis, so that the necessary gap between the rotating shaft 21 and the copper sleeve 61 as an explosion-proof joint surface is maintained, and the relevant electrical insulation standard requirements are met. In addition, the conversion switch 2 is fixed by the pressing plate 3, so that the coaxial displacement of the rotating shaft 21 can be avoided during the installation process, and the coaxial displacement is further limited. The design can effectively prevent abnormal wear between the copper sleeve 61 and the rotating shaft 21 caused by the displacement. The technical scheme can realize the technical effects of guaranteeing electrical gap and preventing component wear.

[0026] It is worth mentioning that the first shell 1 is provided with a wire penetrating hole 12 for the conversion switch 2, and the wire penetrating hole 12 is filled with epoxy resin 13. The epoxy resin 13 is used for packaging or filling, so that the electric arc generated during the opening and closing operation of the conversion switch 2 is effectively blocked, and the electric arc is prevented from entering the second shell 5, so that the overall electrical performance of the product is improved.

[0027] It is worth mentioning that the second shell 5 is further provided with a connecting plate 51, a plurality of wire connection terminals 511 are arranged on two sides of the connecting plate 51, the wire connection terminals 511 are electrically connected with wire connection terminals 511 of the conversion switch 2, and a partition plate 512 is arranged between adjacent wire connection terminals 511. Different from the prior art that the wire connection terminals 511 are arranged in the first shell 1, the connecting plate 51 is arranged in the second shell 5 in the technical scheme, the wire connection terminals 511 only need to be electrically connected with external equipment, and the sealing structure of the first shell 1 does not need to be damaged, so that the influence of aging and failure of the sealing ring on the overall electrical performance of the first shell 1 is avoided. In addition, the partition plate 512 is arranged, and the creepage distance between adjacent wire connection terminals 511 is increased.

[0028] It is worth mentioning that the second shell 5 is provided with a wire outlet 52, the wire outlet 52 is provided with a sealing sleeve 53, the end surface of the sealing sleeve 53 is provided with a gasket 54, the wire outlet 52 is threadedly connected with a pressing nut 55, and the pressing nut 55 abuts against the gasket 54.

[0029] It is worth mentioning that the first shell 1 is provided with the cover plate 6, and the cover plate 6 is provided with the copper sleeve 61.

[0030] It is worth mentioning that the switch 2 is provided with a rotating shaft 21, and passes through the copper sleeve 61, and the rotating shaft 21 and the copper sleeve 61 are provided with an explosion-proof joint surface 22, the upper and lower parts of the rotating shaft 21 are provided with O-shaped sealing rings 23, the rotating shaft 21 is provided with a rotating handle 24, the explosion-proof joint surface 22 refers to the structure that the copper sleeve 61 on the cover plate 6 and the corresponding surface of the rotating shaft 21 are matched together, its main function is to prevent the internal explosion from spreading to the explosive gas mixture around the first shell 1, it is also called "flame path", the design of the explosion-proof joint surface 22 needs to meet specific technical requirements, including the width of the explosion-proof surface and the gap of the explosion-proof joint surface 22, for example, for the cylindrical explosion-proof joint surface 22, the gap refers to the radial gap (diameter difference), if the parameters of the explosion-proof joint surface 22 are lower than the standard requirements, the explosion-proof performance will fail, that is, the explosion flame spreads from the inside of the first shell 1 to the outside, so that the protection function is lost, the O-shaped sealing ring 23 is arranged on the rotating shaft 21, which prevents the external explosive gas mixture from entering the first shell 1 and prevents the internal explosion.

[0031] The above is a further detailed description of the utility model in combination with the specific implementation, which cannot be determined that the specific implementation of the utility model is limited to these descriptions, for ordinary technical personnel in the technical field to which the utility model belongs, without departing from the concept of the utility model, a number of simple deductions or substitutions can be made, all of which should be regarded as belonging to the protection range determined by the claims submitted by the utility model.

Claims

1. An explosion-proof reverse rotation change-over switch against coaxial misalignment, comprising a first housing (1) and a change-over switch (2) disposed therein, characterized in that: The first shell (1) is provided with limiting portions (11) for preventing displacement of the change-over switch (2), and a pressing plate (3) is arranged between the two limiting portions (11), the pressing plate (3) is connected and fixed with the limiting portions (11) by screws (4), and is used for fixing the change-over switch (2).

2. The explosion-proof reverse rotation transfer switch that prevents coaxial deviation according to claim 1, characterized in that: The first shell (1) is provided with a wire hole (12) for the change-over switch (2) to pass through, and the wire hole (12) is filled with epoxy resin (13).

3. The explosion-proof reverse rotation transfer switch that prevents coaxial deviation according to claim 1, characterized in that: A second shell (5) is further arranged, the second shell (5) is provided with a connecting plate (51), the connecting plate (51) is provided with a plurality of wire terminals (511) on both sides, the wire terminals (511) are electrically connected with the wire terminals (511) of the change-over switch (2), and a partition plate (512) is arranged between adjacent wire terminals (511).

4. The explosion-proof reverse rotation transfer switch that prevents coaxial deviation according to claim 3, characterized in that: The second shell (5) is provided with a wire outlet (52), the wire outlet (52) is provided with a sealing sleeve (53), the end surface of the sealing sleeve (53) is provided with a gasket (54), the wire outlet (52) is threadedly connected with a compression nut (55) and abuts against the gasket (54).

5. The explosion-proof reverse rotation transfer switch that prevents coaxial deviation according to claim 1, characterized in that: The first shell (1) is provided with a cover plate (6), and the cover plate (6) is provided with a copper sleeve (61).

6. The explosion-proof reverse rotation transfer switch that prevents coaxial deviation according to claim 5, characterized in that: The change-over switch (2) is provided with a rotating shaft (21) and passes through the copper sleeve (61), an explosion-proof joint surface (22) is arranged between the rotating shaft (21) and the copper sleeve (61), O-shaped sealing rings (23) are arranged on the upper and lower portions of the rotating shaft (21), and the rotating shaft (21) is provided with a rotating handle (24).

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