A disconnecting and closing device for a three-column horizontal rotary disconnector

Abstract

The application relates to the technical field of high-voltage switch equipment, in particular to a breaking and closing device of a three-column horizontal rotary disconnector. The device comprises a base, insulators, static contacts, a rotary blade and a movable contact. Three groups of insulators are arranged on the top of the base, each group of insulators has three insulators, the middle insulator is rotationally connected with the base, the top of the two side insulators is provided with a static contact, the upper end of the middle insulator is fixedly connected with the rotary blade, and the two ends of the rotary blade are provided with movable contacts matched with the static contacts. The static contact is designed as a side U-shaped structure with an outward expansion, and the movable contact is designed as a floating structure capable of horizontally sliding and vertically rotating. When the rotary blade is deformed in the up-down direction, the outward expansion of the horizontal static contact plate opening can guide the movable contact to accurately enter, the horizontal elastic floating of the horizontal movable contact plate is realized through a horizontal insulating sliding block and a second reset spring, and the vertical self-adapting deflection of the vertical movable contact plate is realized through a vertical insulating sliding block and a torsion spring.

Description

Technical Field

[0001] This invention relates to the field of high-voltage switchgear technology, and in particular to an opening and closing device for a three-column horizontal rotary disconnector. Background Technology

[0002] The three-post horizontal rotary disconnector is a widely used high-voltage switchgear in power systems. It is mainly used to connect or disconnect circuits under no-load current conditions to create a clear break and ensure maintenance safety. Its typical structure includes a base, three sets of insulating posts, and a rotary switch. The middle insulating post is driven to rotate by an operating mechanism, which in turn drives the moving contacts at both ends of the switch to close or open the circuit with the stationary contacts on both sides.

[0003] In existing three-post horizontal rotary disconnectors, the stationary contact typically employs a simple sheet-like clamping structure, while the moving contact is a rigidly connected flat plate. During long-term operation, the rotary switch is prone to bending deformation under prolonged stress and environmental temperature changes. Simultaneously, the bearing at the bottom of the intermediate insulator develops gaps after long-term rotational wear, causing the moving contact trajectories at both ends of the switch to deviate. During closing, it's easy for one end of the moving contact to be in contact with the stationary contact while the other end is not yet in contact or has insufficient contact pressure, resulting in closing failure or poor contact. Furthermore, the moving contact has low tolerance for deformation and positional deviations of the rotary switch when mating with the stationary contact. Once mechanical deformation or installation deviation occurs, the moving contact cannot adaptively conform to the stationary contact, leading to a reduced effective contact area, increased contact resistance, and a tendency to cause localized overheating. Summary of the Invention

[0004] In order to overcome the shortcomings of existing disconnecting switches, such as low tolerance for knife deformation and position deviation, which easily leads to closing failure, poor contact, or local overheating, this invention provides a three-column horizontal rotary disconnecting switch opening and closing device.

[0005] The technical solution is as follows: A three-post horizontal rotary disconnector switch opening and closing device includes a base, insulators, stationary contacts, a rotary switch, and moving contacts. Three sets of insulators are installed on the top of the base, with three insulators in each set. The middle insulator is rotatably connected to the base. Stationary contacts are installed on the top of the two side insulators. A rotary switch is fixedly connected to the upper end of the middle insulator. Moving contacts adapted to the stationary contacts are provided at both ends of the rotary switch. The stationary contact includes a contact seat, a vertical stationary contact plate, and a horizontal stationary contact plate. The contact seat and the insulator... The body is connected, with a vertical stationary contact plate vertically connected to the inner side of the contact seat, and horizontal stationary contact plates connected to both the upper and lower sides. The opening ends of the two horizontal stationary contact plates are outwardly flared. The moving contact includes a guide seat, a first return spring, a sliding seat, a vertical moving contact plate, and a horizontal moving contact plate. The guide seat is connected to the end of the rotary switch, and a sliding seat is slidably provided on the outer side of the guide seat. The two are elastically connected by the first return spring. A vertical moving contact plate is provided at one end of the sliding seat facing the contact seat, and horizontal moving contact plates are provided at the lower two ends respectively. Both the vertical and horizontal moving contact plates are electrically connected to the rotary switch.

[0006] Furthermore, the rotary switch includes an outer sleeve, conductive posts, terminal blocks, and flexible connecting wires. The outer sleeve is connected to the top of the middle insulator, and the end of the outer sleeve is connected to the guide seat. The conductive posts are connected inside the outer sleeve, and the two ends of the conductive posts are respectively connected to terminal blocks. The terminal blocks are electrically connected to the vertical contact plate and the horizontal contact plate respectively through the flexible connecting wires.

[0007] Furthermore, the sliding seat includes a horizontal insulating slider, a second return spring, a fixed shaft, a vertical insulating slider, and a torsion spring. Horizontal grooves are provided at both the upper and lower ends of the sliding seat. The horizontal insulating slider is slidably disposed in the horizontal groove. The horizontal insulating slider and the horizontal groove are elastically connected by the second return spring. A vertical groove is provided on the side of the sliding seat away from the guide seat. The fixed shaft is connected in the vertical groove. The vertical insulating slider is rotatably connected to the fixed shaft. The vertical insulating slider and the vertical groove are elastically connected by a torsion spring. The horizontal insulating slider is connected to the horizontal moving contact plate, and the vertical insulating slider is connected to the vertical moving contact plate.

[0008] Furthermore, a first guide slope is provided on the outer side of the horizontal insulating slider facing the stationary contact, and a third guide slope is provided at both the upper and lower ends of the vertical insulating slider side.

[0009] Furthermore, the opening and closing device also includes a reset mechanism, which includes a guide block, a push rod, a push frame, a column, and a limiting component. Guide holes are provided on both the upper and lower sides of the sliding seat, and the guide holes are connected to the horizontal slide groove. A guide block is slidably connected in the guide hole, and a dome push rod is connected to the guide block. A second guide slope is provided on the side of the horizontal insulating slider near the push rod, and a push frame is connected to the guide block. Each set of insulators has a column fixed on the base on both sides, and two limiting components are connected to the upper part of the column.

[0010] Furthermore, the opening and closing device also includes a limit block. The outer side of the guide seat is provided with a limit groove, and the limit block is slidably connected in the limit groove. The limit block is connected to the sliding seat.

[0011] Furthermore, the opening and closing device also includes a support spring, which is fixed to the inner wall of the vertical groove and abuts against the surface of the vertical insulating slider.

[0012] Furthermore, the horizontal moving contact plate on the horizontal insulating slider and the vertical moving contact plate on the vertical insulating slider are both designed to be detachable.

[0013] The beneficial effects of this invention are as follows: 1. This invention designs the stationary contact as an outwardly expanding U-shaped structure and the moving contact as a floating structure that can slide horizontally and rotate vertically. During closing, even if the rotating switch undergoes vertical deformation, the outwardly expanding horizontal stationary contact plate opening can guide the moving contact to accurately enter. The horizontal moving contact plate achieves horizontal elastic floating through a horizontal insulating slider and a second return spring, while the vertical moving contact plate achieves vertical adaptive deflection through a vertical insulating slider and a torsion spring. This multi-degree-of-freedom floating arrangement allows the moving contact to adaptively adhere to the stationary contact plate, effectively compensating for positional deviations caused by switch deformation, bearing wear, or installation errors, ensuring sufficient contact area and stable contact pressure, and significantly improving the closing success rate.

[0014] 2. In this invention, the guide seat and the sliding seat are elastically connected by a first return spring. After one end of the rotating gate has completed contact, the gate can continue to rotate a short distance and compress the first return spring, providing sufficient travel compensation for the other end's contact. This effectively solves the problem of one end being closed while the other is not due to gate deformation, ensuring that both ends of the contact can reliably close.

[0015] 3. Through the reset mechanism, even if the horizontal insulating slider and the horizontal slide groove become stuck due to dust, rust and other impurities falling in during long-term operation, the mechanism can achieve forced reset during the opening process of this device, ensuring that the moving contact returns to the correct initial position after opening, and preparing for the next closing, which significantly improves the long-term operational reliability of the device in harsh outdoor environments. Attached Figure Description

[0016] Figure 1 This is a three-dimensional structural diagram of the entire machine of the present invention.

[0017] Figure 2 This is a three-dimensional structural diagram of a single insulator and a rotary switch of the present invention.

[0018] Figure 3 This is a three-dimensional structural diagram of the stationary contact and the moving contact of the present invention.

[0019] Figure 4This is a three-dimensional structural diagram of the rotary gate and moving contact of the present invention.

[0020] Figure 5 This is a cross-sectional view of the moving contact of the present invention.

[0021] Figure 6 This is a front view of a partial structure of the moving contact of the present invention.

[0022] Figure 7 This is an exploded view of the sliding seat structure of the present invention.

[0023] Figure 8 This is a three-dimensional structural diagram of the reset mechanism of the present invention.

[0024] In the attached diagram, the following are the reference numerals: 1-base, 2-insulator, 3-stationary contact, 31-contact seat, 32-vertical stationary contact plate, 33-horizontal stationary contact plate, 4-rotary switch, 41-outer sleeve, 42-conductive post, 43-terminal block, 44-flexible connecting wire, 5-moving contact, 51-guide seat, 511-first return spring, 52-sliding seat, 521-horizontal groove, 522-vertical groove, 523-horizontal insulating slider, 5231-first guide... 5232-Second guide inclined surface, 524-Second return spring, 525-Fixed shaft, 526-Vertical insulating slider, 5261-Third guide inclined surface, 527-Torsion spring, 53-Vertical contact plate, 54-Horizontal contact plate, 6-Reset mechanism, 61-Guide hole, 62-Guide block, 63-Push rod, 64-Push frame, 65-Column, 66-Limiting component, 7-Limiting groove, 8-Limiting block, 9-Supporting spring. Detailed Implementation

[0025] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0026] An opening and closing device for a three-column horizontal rotary disconnector, such as Figures 1-8As shown, the device includes a base 1, insulators 2, stationary contacts 3, rotary switches 4, and moving contacts 5. Three sets of insulators 2 are evenly spaced along the length of the top of the base 1, with three insulators in each set, and are evenly distributed along the width of the top of the base 1. The lower end of the middle insulator 2 is rotatably connected to the base 1 via a bearing seat, while the lower ends of the two side insulators 2 are fixedly connected to the base 1. A stationary contact 3 is mounted on the top of each insulator 2. A rotary switch 4 is fixedly connected to the upper end of the middle insulator 2. Moving contacts 5, adapted to the stationary contacts 3, are located at both ends of the rotary switch 4. An operating mechanism, which is pulsatorically connected to the middle insulator 2, is provided on the base 1. This operating mechanism drives the rotary switch 4 to rotate, causing the moving contacts 5 at both ends to perform closing or opening actions with the stationary contacts 3 of the two side insulators 2. The stationary contact 3 includes a contact seat 31, a vertical stationary contact plate 32, and a horizontal stationary contact plate 33. The contact seat 31 is fixed to the top of the insulator 2. The contact seat 31 is vertically connected to a vertical stationary contact plate 32 on its inner side. Both the upper and lower sides of the inner side of the contact seat 31 are connected to horizontal stationary contact plates 33. The vertical stationary contact plate 32 and the horizontal stationary contact plate 33 are connected, forming a side U-shaped structure. The end of the horizontal stationary contact plate 33 furthest from the vertical stationary contact plate 32 has an outwardly flared opening to facilitate the entry of the moving contact 5. The moving contact 5 includes a guide seat 51, a first return spring 511, a sliding seat 52, a vertical moving contact plate 53, and a horizontal moving contact plate 54. The guide seat 51... Connected to the end of the rotary switch 4, a sliding seat 52 is slidably provided on the outer side of the guide seat 51. The sliding seat 52 and the guide seat 51 are elastically connected by a first return spring 511. A vertical moving contact plate 53 is provided at one end of the sliding seat 52 facing the contact seat 31. A horizontal moving contact plate 54 is provided at the upper and lower ends of the sliding seat 52, respectively. Both the vertical moving contact plate 53 and the horizontal moving contact plate 54 are electrically connected to the rotary switch 4 and cooperate with the vertical stationary contact plate 32 and the horizontal stationary contact plate 33, respectively.

[0027] like Figures 3-4 As shown, the rotary switch 4 includes an outer sleeve 41, a conductive post 42, a terminal block 43, and a flexible connecting wire 44. The outer sleeve 41 is fixed to the top of the rotating insulator 2 in the middle. The guide seat 51 is provided with a socket for insertion and mating with the outer sleeve 41. The conductive post 42 is connected inside the outer sleeve 41. The two ends of the conductive post 42 are respectively connected to the terminal block 43. The terminal block 43 is electrically connected to the vertical contact plate 53 and the horizontal contact plate 54 respectively through the flexible connecting wire 44.

[0028] like Figure 5As shown, the sliding seat 52 includes a horizontal insulating slider 523, a second return spring 524, a fixed shaft 525, a vertical insulating slider 526, and a torsion spring 527. Horizontal grooves 521 are provided at both the upper and lower ends of the sliding seat 52. The horizontal insulating slider 523 is slidably disposed within the horizontal groove 521. The horizontal insulating slider 523 is elastically connected to the inner wall of the horizontal groove 521 via the second return spring 524. A vertical groove 522 is provided on the side of the sliding seat 52 away from the guide seat 51. The fixed shaft 525 is connected within the vertical groove 522. The vertical insulating slider 526 is rotatably connected to the fixed shaft 525. The vertical insulating slider 526 is elastically connected to the inner wall of the vertical groove 522 via the torsion spring 527. The horizontal insulating slider 523 and the horizontally moving contact plate 54, and the vertical insulating slider 526 and the vertically moving contact plate 53 are both designed to be detachably connected. When the contact plate is worn or damaged, it can be disassembled and replaced individually without replacing the entire slider assembly.

[0029] like Figure 6 As shown, the horizontal insulating slider 523 has a first guide slope 5231 on the side facing the stationary contact 3, and the vertical insulating slider 526 has a third guide slope 5261 at both the upper and lower ends facing the stationary contact 3, which are used to guide the moving contact 5 to smoothly enter the side U-shaped structure composed of the vertical stationary contact plate 32 and the horizontal stationary contact plate 33.

[0030] like Figure 1 , Figure 7 and Figure 8 As shown, the opening and closing device also includes a reset mechanism 6. The reset mechanism 6 includes a guide block 62, a push rod 63, a push frame 64, a column 65, and a limiting member 66. The upper and lower sides of the sliding seat 52 are provided with guide holes 61, which are respectively connected to the upper and lower horizontal sliding grooves 521. Guide blocks 62 are slidably connected to the front and rear sides of the guide holes 61. A cylindrical push rod 63 is connected between the opposite ends of the two guide blocks 62. The horizontal insulating slider 523 is provided with a second guide inclined surface 5232 on the side near the push rod 63. A push frame 64 is connected between the two guide blocks 62 and is slidably inserted through the sliding seat 52. Each set of insulators Both sides of the base 2 are provided with columns 65, which are fixedly connected to the top of the base 1. The upper part of the two columns 65 is respectively connected to two limiting pieces 66. When the rotary switch 4 rotates to perform the opening action, the pushers 64 on the upper and lower sides are blocked by the two limiting pieces 66 on the same column 65. When the pushers 64 are blocked, the rotary switch 4 continues to drive the guide seat 51 to move, so that the pusher 63 pushes the horizontal insulating slider 523 outward through the second guide inclined surface 5232. This can effectively prevent impurities from falling into the gap between the horizontal insulating slider 523 and the horizontal slide groove 521 after the second reset spring 524 is compressed, which would prevent the normal reset.

[0031] like Figure 4 and Figure 8 As shown, the opening and closing device also includes a limiting block 8. The top and bottom of the guide seat 51 are provided with limiting grooves 7 on both the front and rear sides. Each limiting groove 7 is slidably connected to a limiting block 8. The limiting block 8 is connected to the sliding seat 52. The cooperation between the limiting groove 7 and the limiting block 8 is used to limit the sliding stroke of the sliding seat 52 on the guide seat 51. When the sliding gap between the sliding seat 52 and the guide seat 51 cannot be reset normally due to impurities falling in, it can also be forcibly reset by the reset mechanism 6.

[0032] like Figure 7 As shown, the opening and closing device also includes a support spring 9. The support spring 9 is symmetrically fixed to the inner wall of the vertical groove 522. The two support springs 9 are located on the front and rear sides of the fixed shaft 525 respectively. The support spring 9 abuts against the surface of the vertical insulating slider 526. The support spring 9 is used to provide stable support for the vertical insulating slider 526, prevent it from generating unnecessary axial swing under equipment vibration, thereby avoiding fatigue damage to the torsion spring 527 due to continuous alternating load, and ensuring that the angle between the vertical moving contact plate 53 and the vertical stationary contact plate 32 remains stable and reliable.

[0033] This invention primarily addresses the following problems: After long-term operation, the rotary switch 4 may deform under stress, or the bearing at the bottom of the intermediate insulator 2 may wear out. Simultaneously, the stationary contact 3, under prolonged pressure, may expand outwards, increasing the gap. These factors may lead to insufficient contact area between the moving and stationary contacts 3 during closing, or even the moving contact 5 on one side of the rotary switch 4 may have contacted the stationary contact 3 while the other side has not, resulting in closing failure. Therefore, this device achieves reliable closing and opening through the following method.

[0034] When the circuit is closed, the operating mechanism drives the intermediate insulator 2 to rotate, which in turn drives the rotary switch 4 to rotate. First, the end of the horizontal stationary contact 33 furthest from the vertical stationary contact 32 has an outwardly flared opening. Even if the rotary switch 4 deforms vertically, it can still guide the moving contact 5 smoothly into the side U-shaped structure formed by the vertical stationary contact 32 and the horizontal stationary contact 33. When the moving contact 5 enters, the first guide slope 5231 contacts the horizontal stationary contact 33. Under the action of the second return spring 524, the horizontal moving contact 54 and the horizontal insulating slider 523 are compressed and retract into the horizontal groove 521. Simultaneously, the elastic force of the second return spring 524 ensures that the horizontal moving contact 54 and the horizontal stationary contact 33 are tightly fitted together, guaranteeing sufficient contact area. Subsequently, the vertical moving contact 53 contacts the vertical stationary contact 32. Even if the outer sleeve 41 and the conductive post 42 are bent and deformed, the vertical insulating slider 526 is rotatably connected to the sliding seat 52 through the fixed shaft 525. When the vertical moving contact plate 53 is pressed, it can adaptively rotate and stick to the vertical stationary contact plate 32, ensuring reliable contact.

[0035] Furthermore, the guide seat 51 and the sliding seat 52 are elastically connected by the first return spring 511. After the vertical moving contact plate 53 contacts the vertical stationary contact plate 32, the rotary gate 4 can continue to rotate a short distance to compress the first return spring 511, thereby avoiding the situation where one end of the contact is in contact while the other end is not due to the deformation of the rotary gate 4.

[0036] When the circuit breaker is opened, the operating mechanism drives the rotary switch 4 to rotate in the opposite direction. When the pusher 64 rotates to the point where it is blocked by the limiter 66, the pusher rod 63 pushes the horizontal insulating slider 523 outward through the second guide ramp 5232. Even if the horizontal insulating slider 523 is stuck due to impurities, it can still be forcibly reset. The limiter 66 is preferably a screw, which is installed on the column 65 through a threaded connection. The distance of the protrusion at the end of the limiter 66 can be adjusted to prevent damage to the device due to insufficient push distance or excessive pressure caused by deformation of the rotary switch 4. When the horizontal insulating slider 523 is compressed into the horizontal groove 521, the second guide ramp 5232 can also push the pusher rod 63 and the pusher 64 to reset.

[0037] It should be understood that this embodiment is for illustrative purposes only and is not intended to limit the scope of the invention. Furthermore, it should be understood that after reading the teachings of this invention, those skilled in the art can make various alterations or modifications to the invention, and these equivalent forms also fall within the scope defined by the appended claims.

Claims

1. A three-post horizontal rotary disconnector switch opening and closing device, comprising a base (1), an insulator (2), a stationary contact (3), a rotary switch (4), and a moving contact (5). Three sets of insulators (2) are arranged on the top of the base (1), each set containing three insulators (2). The middle insulator (2) is rotatably connected to the base (1). Stationary contacts (3) are installed on the tops of the insulators (2) on both sides. A rotary switch (4) is fixedly connected to the upper end of the middle insulator (2). Moving contacts (5) adapted to the stationary contacts (3) are provided at both ends of the rotary switch (4). The device is characterized in that… The stationary contact (3) includes a contact seat (31), a vertical stationary contact plate (32), and a horizontal stationary contact plate (33). The contact seat (31) is connected to the insulator (2). The vertical stationary contact plate (32) is vertically connected to the inner side of the contact seat (31), and the horizontal stationary contact plates (33) are connected to both the upper and lower sides. The opening ends of the two horizontal stationary contact plates (33) are outwardly flared. The moving contact (5) includes a guide seat (51), a first return spring (511), a sliding seat (52), and a vertical moving contact plate (53). 3) The guide seat (51) is connected to the end of the rotary switch (4) and the horizontal contact plate (54). The guide seat (51) is slidably provided with a sliding seat (52) on the outside. The two are elastically connected by the first reset spring (511). The sliding seat (52) is provided with a vertical contact plate (53) at one end facing the contact seat (31), and the lower two ends are provided with horizontal contact plates (54). The vertical contact plate (53) and the horizontal contact plate (54) are both electrically connected to the rotary switch (4).

2. The opening and closing device of a three-column horizontal rotary disconnector according to claim 1, characterized in that, The rotary switch (4) includes an outer tube (41), a conductive post (42), a terminal block (43), and a flexible connecting wire (44). The outer tube (41) is connected to the top of the middle insulator (2), and the end of the outer tube (41) is connected to the guide seat (51). The conductive post (42) is connected inside the outer tube (41). The two ends of the conductive post (42) are respectively connected to the terminal block (43). The terminal block (43) is electrically connected to the vertical contact plate (53) and the horizontal contact plate (54) respectively through the flexible connecting wire (44).

3. The opening and closing device of a three-column horizontal rotary disconnector according to claim 1, characterized in that, The sliding seat (52) includes a horizontal insulating slider (523), a second return spring (524), a fixed shaft (525), a vertical insulating slider (526), ​​and a torsion spring (527). Horizontal grooves (521) are provided at both the upper and lower ends of the sliding seat (52). The horizontal insulating slider (523) is slidably disposed within the horizontal groove (521). The horizontal insulating slider (523) and the horizontal groove (521) are elastically connected by the second return spring (524). (52) A vertical groove (522) is provided on the side away from the guide seat (51). A fixed shaft (525) is connected in the vertical groove (522). A vertical insulating slider (526) is rotatably connected to the fixed shaft (525). The vertical insulating slider (526) and the vertical groove (522) are elastically connected by a torsion spring (527). The horizontal insulating slider (523) is connected to the horizontal moving contact plate (54). The vertical insulating slider (526) is connected to the vertical moving contact plate (53).

4. The opening and closing device of a three-column horizontal rotary disconnector according to claim 3, characterized in that, The horizontal insulating slider (523) has a first guide slope (5231) on the side facing the stationary contact (3) on the outside, and a third guide slope (5261) is provided at both the upper and lower ends of the vertical insulating slider (526).

5. The opening and closing device of a three-column horizontal rotary disconnector according to claim 3, characterized in that, The opening and closing device also includes a reset mechanism (6). The reset mechanism (6) includes a guide block (62), a push rod (63), a push frame (64), a column (65), and a limiting member (66). The upper and lower sides of the sliding seat (52) are provided with guide holes (61). The guide holes (61) are connected to the horizontal slide groove (521). The guide block (62) is slidably connected in the guide hole (61). The dome push rod (63) is connected on the guide block (62). The horizontal insulating slider (523) is provided with a second guide slope (5232) on the side near the push rod (63). The push frame (64) is connected on the guide block (62). Each set of insulators (2) is provided with a column (65) fixed on the base (1) on both sides. Two limiting members (66) are connected to the upper part of the column (65).

6. The opening and closing device of a three-column horizontal rotary disconnector according to claim 5, characterized in that, The opening and closing device also includes a limit block (8), and a limit groove (7) is provided on the outside of the guide seat (51). The limit block (8) is slidably connected in the limit groove (7), and the limit block (8) is connected to the sliding seat (52).

7. The opening and closing device of a three-column horizontal rotary disconnector according to claim 3, characterized in that, The opening and closing device also includes a support spring (9), and the support spring (9) is fixed to the inner wall of the vertical groove (522). The support spring (9) abuts against the surface of the vertical insulating slider (526).

8. The opening and closing device of a three-column horizontal rotary disconnector according to claim 3, characterized in that, The horizontal moving contact plate (54) on the horizontal insulating slider (523) and the vertical moving contact plate (53) on the vertical insulating slider (526) are both designed to be detachable.

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