Air-blowing type contact structure and starting isolating switch with same

Abstract

The invention discloses an air-blowing type contact structure and a starting isolating switch with the same, diffusion extinguishing of an electric arc is accelerated by air blowing, the ablation resistance of a contact is improved, and the air-blowing type contact structure comprises a static contact, a moving end wire outlet seat, a moving contact, an air guide pipe and an insulating pull rod; an end cover is arranged at the other end of the movable end wire outlet seat; the moving contact is hollow, and the outer wall of the moving contact slidably abuts against the inner wall of the moving end wire outlet seat; one end of the moving contact can slide out of the moving end wire outlet seat and is electrically contacted with the static contact; the gas-guide tube is coaxially fixed in the moving contact; the insulating pull rod penetrates through the end cover and can linearly move relative to the end cover; one end of the insulating pull rod is in transmission connection with the execution mechanism, and the other end is screwed on the inner wall of one end of the moving contact away from the static contact to drive the moving contact to slide; the insulating pull rod is provided with a plurality of air holes communicated with the inner cavity of the gas-guide tube corresponding to the outer wall of the inner cavity of the moving-end wire outlet seat; an air chamber is formed between the inner wall of the moving end wire outlet seat and the outer wall of the insulating pull rod, and the moving contact slides to change the volume of the air chamber and enable air flow to circulate through the air guide pipe.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of pumped storage switching, in particular to a gas-blowing contact structure and a start-up disconnecting switch with the same. BACKGROUND

[0002] The start-up disconnecting switch is an important switching device in the process of starting and stopping and working condition conversion of the pumped storage power station unit. The start-up disconnecting switch should have the ability to open and close the no-load capacitive current of the starting bus, and the rated capacitive opening and closing current should not be less than the maximum no-load capacitive current of the starting bus.

[0003] In the actual application of the pumped storage power station, the closed bus center conductor and the bus shell connected with the start-up disconnecting switch are coaxial conductors, which can be equivalent to a capacitor. During the opening and closing process of the start-up disconnecting switch, there will be a small capacitive current opening and closing phenomenon. Since the medium of the switch breaking point is air, the breaking point distance is relatively small, and the contact movement speed is slow. According to the operation characteristics of the pumped storage power station, the start-up disconnecting switch operates frequently, and the contact ablation problem of the start-up disconnecting switch is more serious. Although the copper-tungsten material moving and static end arc contacts are designed in the contact structure of the start-up disconnecting switch at present to improve the anti-ablation ability, the contact ablation problem has not been completely solved.

[0004] Therefore, how to provide a start-up disconnecting switch with improved anti-ablation ability of the contact is a problem to be solved by those skilled in the art. SUMMARY

[0005] Therefore, the present application provides a gas-blowing contact structure and a start-up disconnecting switch with the same, which uses air blowing to accelerate the diffusion and extinction of the electric arc and improve the anti-ablation ability of the contact.

[0006] In order to achieve the above-mentioned purpose, the present application adopts the following technical solutions: A gas-blowing contact structure, comprising: a static contact, a dynamic end outgoing line seat, one end of the dynamic end outgoing line seat being open, and the other end being fixed with an end cover; a dynamic contact, the dynamic contact being hollow inside and the outer wall thereof being in sliding abutment with the inner wall of the dynamic end outgoing line seat; one end of the dynamic contact being slidable out of the dynamic end outgoing line seat and electrically contacting the static contact; a gas guide pipe, the gas guide pipe being coaxially fixed in the dynamic contact; an insulating pull rod, the insulating pull rod penetrating through the end cover and being linearly movable relative to the end cover; one end of the insulating pull rod being transmissionally connected with an execution mechanism, and the other end being screwed in the inner wall of the end of the dynamic contact away from the static contact to drive the sliding of the dynamic contact; a plurality of gas holes being formed in the outer wall of the inner cavity of the dynamic end outgoing line seat and communicating with the inner cavity of the gas guide pipe; The inner wall of the dynamic end outlet seat and the outer wall of the insulating pull rod form an air chamber, and the sliding of the dynamic contact changes the volume of the air chamber and makes the air flow through the air guide pipe.

[0007] The beneficial effects of the technical scheme are that the dynamic contact is close to the static contact for closing operation, and the dynamic contact is away from the static contact for opening operation, and in the opening and closing operation process, the sliding of the dynamic contact relative to the dynamic end outlet seat changes the volume of the air chamber between the insulating pull rod and the dynamic end outlet seat, the change of the volume of the air chamber makes the gas flow into the air guide pipe, and the gas can blow through the surface of the static contact or the dynamic contact in the flow process, reducing the ablation of the arc to the contact.

[0008] Preferably, the dynamic contact includes a dynamic end main contact and a dynamic end arc contact, the dynamic end main contact is a hollow column structure and the outer wall thereof is in sliding abutment with the inner wall of the dynamic end outlet seat, the dynamic end arc contact is threadedly connected to one end of the dynamic end main contact away from the insulating pull rod, and a gas guide channel communicating with the inner cavity of the air guide pipe is formed in the dynamic end arc contact. The dynamic end arc contact realizes electrical contact with the static contact, and the gas flow in the air guide pipe can enter and exit through the gas guide channel.

[0009] Preferably, a first guide sleeve is fixed to the inner wall of the open end of the dynamic end outlet seat, and the dynamic end main contact is slidingly connected in the first guide sleeve. The guide sleeve reduces the friction resistance in the sliding process of the dynamic end main contact.

[0010] Preferably, a hollow pull rod joint is embedded in the end of the insulating pull rod corresponding to the inner cavity of the dynamic end outlet seat, the pull rod joint is threadedly connected to the inner wall of one end of the dynamic end main contact away from the dynamic end arc contact, and the outer wall of the pull rod joint is provided with the air hole. The pull rod joint ensures that the gas can effectively flow when the volume of the air chamber changes.

[0011] Preferably, the air guide pipe is provided with a bell mouth at both ends, and the end faces of the two bell mouths are in abutment with the two end faces of the dynamic end arc contact and the pull rod joint, respectively. The bell mouths at both ends of the air guide pipe accelerate the guiding effect of the gas flow, and the gas flow can act on the surface of the contact after the volume of the air chamber changes.

[0012] Preferably, a through hole is formed in the middle of the end cover, a second guide sleeve is fixed to the inner wall of the through hole, and the insulating pull rod is slidingly connected in the second guide sleeve. The second guide sleeve facilitates the sliding of the insulating pull rod at the end cover, so that the insulating pull rod can drive the dynamic contact to slide in the dynamic end outlet seat.

[0013] The application further provides the air-blast starting isolating switch which comprises the air-blast contact structure in the technical scheme and further comprises a shell and a support base; a plurality of support rods are fixed to the inner wall of the top end of the shell; the static contact is fixed to the plurality of support rods; the support base is fixed in the shell and below the static contact, the support base has a pull rod movement space; the dynamic end outlet seat is located in the pull rod movement space and is fixed to the inner top wall of the support base at the end away from the insulating pull rod; the end of the insulating pull rod away from the dynamic end outlet seat penetrates through the support base and the shell and is transmission connected with an executing mechanism. The insulating pull rod is transmission connected with the executing mechanism, the insulating pull rod drives the dynamic contact to slide, the volume of the air chamber changes in the sliding process of the dynamic contact, the change of the volume of the air chamber makes the airflow in the air chamber enter and exit through the air guide pipe, and the airflow acts on the surface of the dynamic contact or the static contact in the entering and exiting process to blow up, thereby reducing the ablation caused by the electric arc.

[0014] Preferably, the air-blast starting isolating switch further comprises a static end outlet seat; the static end outlet seat is fixed to the plurality of support rods; and the static contact is fixed to the bottom surface of the static end outlet seat. The static end outlet seat is used for mounting the static contact.

[0015] Preferably, the air-blast starting isolating switch further comprises an insulating protective sleeve; the two ends of the insulating protective sleeve are fixed to the two end faces of the static end outlet seat and the support base opposite to each other; and the insulating protective sleeve covers the dynamic contact. The insulating protective sleeve is used for meeting the insulation requirement in the airflow process, so that the airflow process has little influence on the operating characteristics of the switch.

[0016] Preferably, the top surface and the bottom surface of the support base are both flange surfaces; one end of the insulating protective sleeve is bolted to the flange surface at the top end of the support base; a support post insulator is bolted to the flange surface at the bottom end of the support base; and the insulating pull rod is slidingly connected in the support post insulator.

[0017] According to the technical scheme, compared with the prior art, the air-blast contact structure and the starting isolating switch having the same are provided, the air blowing is used to accelerate the diffusion and extinguishing of the electric arc, the ablation resistance of the contact is improved, the existing switch is improved without causing great influence on the structure and performance of the product. BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to more clearly illustrate the technical scheme in the embodiments of the application or the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced below. Obviously, the drawings in the following description are only embodiments of the application, and other drawings can be obtained by those skilled in the art without creative effort on the basis of the provided drawings.

[0019] Figure 1A start isolating switch structure schematic diagram provided by the present application; Figure 2 A contact structure sectional view provided by the present application; Figure 3 A support seat structure schematic diagram provided by the present application; Figure 4 A pull rod joint structure schematic diagram provided by the present application; Figure 5 A moving and static contact sectional view provided by the present application; Figure 6 A gas flow direction schematic diagram in the opening process provided by the present application; Figure 7 A gas flow direction schematic diagram in the closing process provided by the present application.

[0020] Wherein, 1 - shell; 11 - support rod; 12 - support insulator; 2 - support seat; 21 - flange face; 3 - insulation protective sleeve; 4 - moving end outgoing line seat; 41 - end cover; 42 - second guide sleeve; 43 - gas chamber; 5 - insulation pull rod; 51 - pull rod joint; 52 - gas hole; 6 - static end outgoing line seat; 7 - static contact; 71 - shielding cover; 72 - static end main contact; 73 - static end arc contact; 8 - moving contact; 81 - moving end main contact; 82 - moving end arc contact; 83 - first guide sleeve; 84 - gas guide channel; 9 - gas guide pipe. DETAILED DESCRIPTION

[0021] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the protection scope of the present application.

[0022] Embodiment 1 The start isolating switch of transmission has many problems of contact ablation when opening and closing small capacitive current. According to the air blast type contact structure in the embodiments of the present application, by designing reasonable gas circuit, in the opening and closing arc starting process, the gas can flow smoothly in the gas circuit, and flow through the arc starting part of the contact at a certain speed, so as to blow away the arc, such as Figure 2 、 4, 5, the contact structure of the embodiment includes the static contact 7, the dynamic end outgoing line seat 4, the dynamic contact 8, the gas guide pipe 9 and the insulating pull rod 5; one end of the dynamic end outgoing line seat 4 is open, and the other end is fixed with the end cover 41; the dynamic contact 8 is hollow inside and the outer wall thereof is in sliding abutment with the inner wall of the dynamic end outgoing line seat 4; one end of the dynamic contact 8 can slide out of the dynamic end outgoing line seat 4 and electrically contact the static contact 7; the gas guide pipe 9 is coaxially fixed in the dynamic contact 8, and the inner cavity of the gas guide pipe 9 is used as a gas path; the insulating pull rod 5 penetrates through the end cover 41 and can linearly move relative to the end cover 41; one end of the insulating pull rod 5 is transmissionally connected to the executing mechanism, and the other end is screwed on the inner wall of the end of the dynamic contact 8 away from the static contact 7 to drive the sliding of the dynamic contact 8; the insulating pull rod 5 is provided with a plurality of air holes 52 corresponding to the outer wall of the inner cavity of the dynamic end outgoing line seat 4, which are communicated with the inner cavity of the gas guide pipe 9; wherein, the gas chamber 43 is formed between the inner wall of the dynamic end outgoing line seat 4 and the outer wall of the insulating pull rod 5, and the sliding of the dynamic contact 8 can change the volume of the gas chamber 43 and make the gas flow through the gas guide pipe 9.

[0023] As shown in Figure 6 and 7 , the dynamic end outgoing line seat, the insulating pull rod and the dynamic contact form a closed gas chamber in structure, the gas guide pipe is used as a gas path in the dynamic contact, and the sliding of the dynamic contact changes the volume of the gas chamber and makes the gas flow in and out of the gas path, and the gas blows on the surfaces of the dynamic contact and the static contact when flowing in and out of the gas path, thereby reducing the ablation of the contacts by the arc and improving the service performance and durability of the switch.

[0024] In order to further optimize the above technical scheme, the dynamic contact 8 includes the dynamic end main contact 81 and the dynamic end arc contact 82; the dynamic end main contact 81 is a hollow column structure and the outer wall thereof is in sliding abutment with the inner wall of the dynamic end outgoing line seat 4, and the dynamic end arc contact 82 is threadedly connected to the end of the dynamic end main contact 81 away from the insulating pull rod 5, and the dynamic end arc contact 82 is provided with the gas guide passage 84 communicated with the inner cavity of the gas guide pipe 9.

[0025] As shown in Figure 5 , the static contact 7 includes the shielding cover 71, the static end main contact 72 and the static end arc contact 73; the static end main contact 72 is hollow inside and fixed in the shielding cover 71, and the static end arc contact 73 is fixed in the shielding cover 71 and located in the center of the static end main contact 72, one end of the static end arc contact 73 is exposed from the end face of the shielding cover 71, and the outer wall of the static end arc contact 73 has an insertion gap with the inner wall of the static end main contact 72. In the closing process, as shown in Figure 7 , the dynamic contact 8 slides towards the static contact 7, the dynamic end arc contact 82 first breaks through the static end arc contact 73 to generate arc, the volume of the gas chamber 43 increases, the gas flow enters the gas chamber 43 from the external environment through the gas guide passage 84, and the gas flow blows on the surface of the dynamic end arc contact 82, and after the closing is completed, the dynamic end arc contact 82 is sleeved on the static end arc contact 73 and inserted into the insertion gap. When opening, as shown in Figure 6As shown, when the circuit breaker is open, the moving contact 8 moves away from the stationary contact 7. That is, during opening, the moving arc contact 82 and the stationary arc contact 73 separate and begin to arc, reducing the volume of the gas chamber 43. The gas in the gas chamber 43 enters the air duct of the moving arc contact 82 through the air guide pipe 9 and blows air onto the stationary arc contact 73. This invention reduces the ablation problem caused by the electric arc on the contacts by blowing air onto the contact surface during opening and closing.

[0026] In some other specific embodiments, to improve the sliding effect of the moving contact relative to the moving end outlet seat, a first guide sleeve 83 is fixed to the inner wall of the open end of the moving end outlet seat 4, and the moving end main contact 81 is slidably connected in the first guide sleeve 83.

[0027] In this embodiment, to ensure that the gas in the gas chamber can effectively enter and exit the gas guide tube, a hollow pull rod connector 51 is embedded at the end of the insulating pull rod 5 corresponding to the inner cavity of the moving end outlet seat 4. The pull rod connector 51 is threaded to the inner wall of the moving end main contact 81 away from the moving end arc contact 82; the outer wall of the pull rod connector 51 is provided with air holes 52. At least four air holes 52 are provided in the circumference of the pull rod connector 51, and the air holes 52 are arranged obliquely on the outer wall of the pull rod connector 51. By setting the pull rod connector 51, the gas flow is achieved without the need to open holes in the rod body of the insulating pull rod 5, thus ensuring the overall performance and operational stability of the insulating pull rod 5.

[0028] In some other specific embodiments, the insulating tie rod 5 is an epoxy fiberglass pull rod.

[0029] To further optimize the above technical solution and accelerate the airflow in and out of the air guide pipe, both ends of the air guide pipe 9 are provided with flared mouths, and the end faces of the two flared mouths abut against the two end faces of the moving end arc contact 82 and the pull rod joint 51, respectively.

[0030] In some other specific embodiments, in order to ensure that the insulating pull rod can move the contact flexibly, the end cap 41 has a through hole in the middle, and a second guide sleeve 42 is fixed to the inner wall of the through hole, and the insulating pull rod 5 is slidably connected in the second guide sleeve 42.

[0031] Example 2 This invention discloses a pneumatic start disconnect switch, which adopts a pneumatic contact structure as described in Embodiment 1, and further includes a housing 1 and a support base 2; multiple support rods 11 are fixed to the inner wall of the top of the housing 1; a stationary contact 7 is fixed on the multiple support rods 11; the support base 2 is fixed inside the housing 1 and located below the stationary contact 7, and the support base 2 has a pull rod movement space; the moving end outlet seat 4 is located in the pull rod movement space, and its end away from the insulating pull rod 5 is fixed to the inner top wall of the support base 2; the end of the insulating pull rod 5 away from the moving end outlet seat 4 passes through the support base 2 and the housing 1 and is connected to the actuator.

[0032] like Figure 1As shown, one end of multiple support rods is fixed to the inner wall of the top of the housing, and the other end is fixed to the moving contact. The support base is used to connect the moving contact and the stationary contact. The support base is a hollow cylinder, and its inner cavity has a transmission space for the insulating pull rod. The movement of the insulating pull rod drives the moving contact to slide along the moving end outlet seat.

[0033] To further optimize the above technical solution, a stationary end outlet 6 is also included; the stationary end outlet 6 is fixed on multiple support rods 11; and the stationary contact 7 is fixed on the bottom surface of the stationary end outlet 6.

[0034] In this embodiment, to meet the insulation requirements of the gas circuit system, an insulating protective sleeve 3 is also included; the two ends of the insulating protective sleeve 3 are fixed to the two end faces opposite to the stationary end outlet seat 6 and the support seat 2, respectively, and the insulating protective sleeve 3 covers the moving contact 8.

[0035] To further optimize the above technical solution, the top and bottom surfaces of the support base 2 are both flange faces 21. The flange face 21 at the top of the support base 2 is bolted to one end of the insulating protective sleeve 3, and the flange face 21 at the bottom of the support base 2 is bolted to the post insulator 12. The insulating tie rod 5 is slidably connected inside the post insulator 12.

[0036] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to the method section.

[0037] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A pneumatic contact structure, characterized in that, include: Static contact (7). Moving end outlet (4), one end of the moving end outlet (4) is open, and the other end is fixed with an end cap (41). The moving contact (8) is hollow inside and its outer wall slides against the inner wall of the moving end outlet seat (4); one end of the moving contact (8) can slide out of the moving end outlet seat (4) and make electrical contact with the stationary contact (7). Air guide tube (9), which is coaxially fixed inside the moving contact (8); An insulating pull rod (5) passes through the end cap (41) and can move linearly relative to the end cap (41); one end of the insulating pull rod (5) is connected to the actuator, and the other end is screwed to the inner wall of the moving contact (8) away from the stationary contact (7) to drive the sliding of the moving contact (8); the insulating pull rod (5) has a plurality of air holes (52) corresponding to the outer wall of the inner cavity of the moving end outlet seat (4) that communicate with the inner cavity of the air guide tube (9). An air chamber (43) is formed between the inner wall of the moving end outlet seat (4) and the outer wall of the insulating pull rod (5). The sliding of the moving contact (8) can change the volume of the air chamber (43) and allow airflow to pass through the air guide pipe (9).

2. The air-blowing contact structure according to claim 1, characterized in that, The moving contact (8) includes a moving end main contact (81) and a moving end arc contact (82); the moving end main contact (81) is a hollow column structure and its outer wall slides against the inner wall of the moving end outlet seat (4); the moving end arc contact (82) is threaded to the end of the moving end main contact (81) away from the insulating pull rod (5); the moving end arc contact (82) is provided with an air duct (84) that connects to the inner cavity of the air guide tube (9).

3. The air-blowing contact structure according to claim 2, characterized in that, The inner wall of the open end of the moving end outlet (4) is fixed with a first guide sleeve (83), and the moving end main contact (81) is slidably connected in the first guide sleeve (83).

4. The air-blowing contact structure according to claim 2, characterized in that, A hollow pull rod connector (51) is embedded at the end of the insulating pull rod (5) corresponding to the inner cavity of the moving end outlet seat (4). The pull rod connector (51) is threaded to the inner wall of the moving end main contact (81) away from the moving end arc contact (82). The outer wall of the pull rod connector (51) is provided with the air hole (52).

5. The air-blowing contact structure according to claim 4, characterized in that, Both ends of the air guide tube (9) are provided with flared mouths, and the end faces of the two flared mouths abut against the two end faces of the moving end arc contact (82) and the pull rod joint (51), respectively.

6. The air-blowing contact structure according to claim 1, characterized in that, The end cap (41) has a through hole in the middle, and a second guide sleeve (42) is fixed to the inner wall of the through hole. The insulating pull rod (5) is slidably connected in the second guide sleeve (42).

7. A pneumatic-driven disconnect switch, characterized in that, The air-blowing contact structure according to any one of claims 1 to 6 further includes a housing (1) and a support base (2); a plurality of support rods (11) are fixed to the inner wall of the top of the housing (1); the stationary contact (7) is fixed on the plurality of support rods (11); the support base (2) is fixed inside the housing (1) and located below the stationary contact (7), and the support base (2) has a pull rod movement space; the moving end outlet seat (4) is located in the pull rod movement space and its end away from the insulating pull rod (5) is fixed to the inner top wall of the support base (2); the end of the insulating pull rod (5) away from the moving end outlet seat (4) passes through the support base (2) and the housing (1) and is connected to the actuator.

8. A pneumatic-driven disconnect switch according to claim 7, characterized in that, It also includes a stationary end outlet (6); the stationary end outlet (6) is fixed on multiple support rods (11); the stationary contact (7) is fixed on the bottom surface of the stationary end outlet (6).

9. A pneumatic-driven disconnect switch according to claim 8, characterized in that, It also includes an insulating protective sleeve (3); the two ends of the insulating protective sleeve (3) are fixed to the two end faces opposite to the stationary end outlet seat (6) and the support seat (2), respectively, and the insulating protective sleeve (3) covers the moving contact (8).

10. A pneumatic start disconnect switch according to claim 9, characterized in that, The top and bottom surfaces of the support base (2) are both flange faces (21). The flange face (21) at the top of the support base (2) is bolted to one end of the insulating protective sleeve (3). The flange face (21) at the bottom of the support base (2) is bolted to a post insulator (12). The insulating tie rod (5) is slidably connected inside the post insulator (12).

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