Interlocking mechanism of circuit breaker and disconnecting switch

Abstract

The present invention relates to the field of electrical switchgear, and more particularly to an interlocking mechanism for a circuit breaker and a disconnecting switch, which includes a brake wire, a pin shaft, a compression spring, a pin shaft bracket, and a limit plate. The limit plate is disposed on the main shaft of the disconnecting switch and is located outside the side plate of the disconnecting switch. The pin shaft bracket is disposed inside the side plate of the disconnecting switch. The pin shaft is movably disposed on the pin shaft bracket, and one end of the pin shaft passes through the side plate of the disconnecting switch. A compression spring baffle is provided on the pin shaft, and the compression spring is sleeved on the pin shaft between the pin shaft bracket and the compression spring baffle. One end of the brake wire is connected to the tail end of the pin shaft, and the other end is connected to the main shaft crank arm on the circuit breaker. The brake wire is disposed in a brake wire tube, and one end of the brake wire tube is fixed by a first wire clamp, and the other end is fixed by a second wire clamp. The present invention uses the brake wire to drive the pin shaft to move to achieve interlocking. The brake wire can be bent arbitrarily according to the positions of the circuit breaker and the disconnecting switch, with simple design and convenient debugging.

Description

Technical Field

[0001] The present invention relates to the field of electrical switchgear, and more specifically to an interlocking mechanism between a circuit breaker and a disconnector. Background Art

[0002] In a high-voltage power system, the safety of personnel and equipment is of utmost importance. To meet the configuration requirements to ensure safety, the relevant national power departments have clearly defined the product configuration functions in the power system cabinet (box), namely the "five-prevention" requirements. Among them, "one-prevention" is to prevent the disconnector from being switched on or off under load. However, due to different requirements of customers, the positions of the circuit breaker and the disconnector configured in the cabinet (box) are often uncertain, so it is very difficult to implement the interlocking function between the circuit breaker and the disconnector.

[0003] In the prior art, the interlocking device between the circuit breaker and the disconnector generally uses an electromagnetic lock to achieve this "one-prevention" function. However, through practice, it has been proved that using an electromagnetic lock to achieve the interlocking between the circuit breaker and the disconnector is unreliable, mainly manifested in two aspects. One is that the power system cabinet (box) is an outdoor product without an external power supply, and most of the electromagnetic lock products on the market do not meet the "one-prevention" requirements in terms of usage status. The other is that the damage rate of the electromagnetic lock is very high, especially in an unstable outdoor environment, it is more likely to cause damage.

[0004] In addition, the interlocking devices between the circuit breaker and the disconnector in the prior art also use various mechanical structures to achieve the interlocking purpose. For example, in the Chinese invention patent with the authorization announcement number CN202384215U and the name "An interlocking device between an outdoor high-voltage vacuum circuit breaker and a disconnector", a mechanism using a concave notch and a stop block to achieve interlocking is disclosed. Another example is that in the patent with the authorization announcement number CN105405694U and the name "Interlocking device between a circuit breaker and a disconnector", a mechanism using a connecting rod, an input crank arm, an interlocking plate, etc. to form a four-bar linkage mechanism to achieve interlocking is disclosed. However, as mentioned above, in practice, due to different requirements of customers, the positions of the circuit breaker and the disconnector are often uncertain. Therefore, the above mechanical interlocking mechanisms can only be applied to specific product structures and cannot be applied to all product structures. Summary of the Invention

[0005] The purpose of the present invention is to provide an interlocking mechanism between a circuit breaker and a disconnector, which uses a wire to drive the pin to move to achieve interlocking. The wire can be bent arbitrarily according to the positions of the circuit breaker and the disconnector and can pass through a narrow gap. The design is simple and the debugging is convenient.

[0006] The purpose of the present invention is achieved by the following technical solutions:

[0007] An interlocking mechanism for a circuit breaker and a disconnector, comprising a brake wire, a pin shaft, a compression spring, a pin shaft bracket and a limit plate. The limit plate is arranged on the main shaft of the disconnector and located outside the side plate of the disconnector. The pin shaft bracket is arranged inside the side plate of the disconnector. The pin shaft is movably arranged in the pin shaft bracket, and one end of the pin shaft passes through the side plate of the disconnector. A compression spring baffle is arranged on the pin shaft, and the compression spring is sleeved on the pin shaft between the pin shaft bracket and the compression spring baffle. One end of the brake wire is connected to the tail end of the pin shaft, and the other end is connected to the main shaft crank arm on the circuit breaker. The brake wire is arranged in a brake wire tube, and one end of the brake wire tube is fixed by a first wire clamp, and the other end is fixed by a second wire clamp.

[0008] One end of the brake wire tube close to the main shaft crank arm is fixed by a first wire clamp and the brake wire tube is connected to a tube bracket. A tube bracket through hole is arranged on the tube bracket, and a slot hole is arranged on one side of the tube bracket through hole close to the brake wire tube. The end of the brake wire tube is provided with a brake wire tube end fixed in the slot hole. The brake wire passes through the tube bracket through hole and then is connected to the main shaft crank arm.

[0009] One end of the brake wire tube close to the pin shaft is fixed by a second wire clamp, and the movement track of the brake wire is on the same straight line as the movement track of the pin shaft (4).

[0010] The pin shaft bracket is in a concave shape, wherein the vertical plates on both sides of the pin shaft bracket are welded on the side plate of the disconnector, and a through hole for the pin shaft to pass through is arranged on the middle connecting plate. The compression spring is arranged between the compression spring baffle and the middle connecting plate of the pin shaft bracket.

[0011] The main shaft crank arm is installed on the main shaft of the circuit breaker. A first shaft sleeve, a second shaft sleeve and a snap ring are arranged on the main shaft of the circuit breaker. The main shaft crank arm is arranged between the first shaft sleeve and the second shaft sleeve, and the main shaft crank arm, the first shaft sleeve and the second shaft sleeve are locked by the snap ring.

[0012] When the circuit breaker is in the closed position and the disconnector is in the open state, the pin shaft passes through the limit plate. When the circuit breaker is in the closed position and the disconnector is in the closed state, the pin shaft is located below the limit plate and blocks the limit plate.

[0013] The opening position of the main shaft crank arm is below the closing position.

[0014] The advantages and positive effects of the present invention are as follows:

[0015] 1. The present invention uses a brake wire to drive the pin shaft to move to achieve interlocking. The brake wire can be bent arbitrarily according to the positions of the circuit breaker and the disconnector and can pass through narrow gaps, without being restricted by position and space, and can be adapted to power system cabinets of various types of structures.

[0016] 2. The present invention realizes the locking of the disconnector by the cooperation of the pin shaft and the limit plate on the main shaft of the disconnector. Compared with the electromagnetic lock that uses electricity for locking, the present invention not only saves electric energy, but also can ensure reliable locking regardless of the various states of the disconnector, thereby realizing "one prevention" among the "five-prevention" functions of the switch cabinet (box) (preventing the disconnector from being switched on or off under load), effectively ensuring the personal safety of the operator and greatly improving the use safety of the high-voltage line.

[0017] 3. Compared with other types of interlocking devices, the present invention has a simple structural design and is very convenient for debugging and installation. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is a schematic structural diagram of the present invention;

[0019] Figure 2 is Figure 1 a schematic diagram of the interlocking state of the disconnector in the circuit breaker when it is closed,

[0020] Figure 3 is Figure 1 a schematic diagram of the interlocking state of the disconnector in the circuit breaker when it is open,

[0021] Figure 4 is Figure 2 a front view of the interlocking state of the disconnector,

[0022] Figure 5 is Figure 3 a front view of the interlocking state of the disconnector,

[0023] Figure 6 is Figure 1 a schematic diagram of the circuit breaker,

[0024] Figure 7 is Figure 6 a left view of the circuit breaker,

[0025] Figure 8 is Figure 1 a schematic diagram of the pipe support in

[0026] Among them, 1 is the side plate of the disconnector, 101 is the through hole of the side plate, 2 is the limit plate, 201 is the through hole of the limit plate, 3 is the main shaft, 4 is the pin shaft, the compression spring baffle 401, 5 is the compression spring, 6 is the pin shaft bracket, 7 is the brake wire, 8 is the circuit breaker, 9 is the main shaft crank arm, 10 is the main shaft of the circuit breaker, 11 is the circlip, 12 is the first bushing, 13 is the second bushing, 14 is the first wire clamp, 15 is the second wire clamp, 16 is the brake line pipe, 17 is the pipe support, 18 is the end of the brake line pipe, 19 is the slot hole, 20 is the through hole of the pipe support. DETAILED DESCRIPTION OF THE INVENTION

[0027] The present invention will be further described in detail below with reference to the accompanying drawings.

[0028] The disconnecting switch is provided with a main shaft 3, and the circuit breaker 8 is provided with a main shaft crank arm 9. The above are well-known technologies in the art. As Figures 1 to 8 shown, the present invention includes a brake wire 7, a pin shaft 4, a compression spring 5, a pin shaft bracket 6 and a limit plate 2. The limit plate 2 is arranged on the part of the main shaft 3 outside the side plate 1 of the disconnecting switch. When the main shaft 3 rotates, the limit plate 2 is driven to rotate. The pin shaft bracket 6 is fixedly arranged inside the side plate 1 of the disconnecting switch. The pin shaft 4 is arranged in the pin shaft bracket 6, and one end of the pin shaft 4 passes through the pin shaft bracket 6 and the other end passes through the side plate 1 of the disconnecting switch. As Figures 4 to 5 shown, a side plate through hole 101 for the pin shaft 4 to pass through is arranged on the side plate 1 of the disconnecting switch, and a limit plate through hole 201 for the pin shaft 4 to pass through is arranged on the limit plate 2. As Figure 2 shown, a compression spring baffle 401 is arranged on the pin shaft 4, and the compression spring 5 is sleeved on the pin shaft 4 between the pin shaft bracket 6 and the compression spring baffle 401. One end of the brake wire 7 is connected to the tail end of the pin shaft 4, and the other end is connected to the main shaft crank arm 9 on the circuit breaker 8. The brake wire 7 is arranged in a brake wire tube 16, and one end of the brake wire tube 16 is fixed by a first wire clamp 14, and the other end is fixed by a second wire clamp 15. The brake wire 7 can move freely in the brake wire tube 16. The brake wire tube 16, the first wire clamp 14 and the second wire clamp 15 are all well-known technologies in the art and are commercially available products.

[0029] As Figure 1 and Figure 8 shown, one end of the brake wire tube 16 close to the main shaft crank arm 9 is fixed by a first wire clamp 14, and the brake wire tube 16 is bent and connected to a pipe bracket 17. The pipe bracket 17 can be fixed at a suitable position according to actual needs. A pipe bracket through hole 20 is arranged on the pipe bracket 17, and a slot hole 19 is arranged on one side of the pipe bracket through hole 20 close to the brake wire tube 16. The end of the brake wire tube 16 is provided with a brake wire tube end 18 fixed in the slot hole 19. The brake wire 7 passes through the pipe bracket through hole 20 and then is connected to the main shaft crank arm 9. The diameter of the pipe bracket through hole 20 is larger than the inner diameter of the brake wire tube 16 and smaller than the outer diameter of the brake wire tube end 18. The diameter of the slot hole 19 should make the brake wire tube end 18 just enter and be stuck and fixed. The brake wire tube end 18 prevents the brake wire tube 16 from detaching when the circuit breaker 8 trips, resulting in a change in the state of the brake wire 7 and further causing the interlock to fail. After being led out from the brake wire tube 16, the brake wire 7 can swing freely and be connected to the main shaft crank arm 9 without being restricted by the position of the main shaft crank arm 9. In this embodiment, the pipe bracket 17 can be made of channel steel, and its cross section is concave. The pipe bracket through hole 20 and the slot hole 19 are opened on the middle connecting plate.

[0030] As Figure 1As shown, one end of the brake solenoid tube 16 close to the pin shaft 4 is fixed by the second wire clamp 15, and the position of the second wire clamp 15 needs to ensure that the movement track of the brake wire 7 in the brake solenoid tube 16 is on the same straight line as the movement track of the pin shaft 4, so as to ensure that the pin shaft 4 moves linearly in and out of the limit plate through hole 201 on the limit plate 2.

[0031] As Figures 2 to 3 shown, the pin shaft bracket 6 is welded to the inner side of the disconnector side plate 1. The pin shaft bracket 6 is concave. The vertical plates on both sides of the pin shaft bracket 6 are welded to the disconnector side plate 1. A through hole for the pin shaft 4 to pass through is provided on the middle connecting plate. During welding, first pass one end of the pin shaft 4 through the side plate through hole 101 and the limit plate through hole 201, and then sleeve the other end of the pin shaft 4 with the compression spring 5 and pass it through the through hole on the pin shaft bracket 6. Pull and contract the compression spring 5 back and forth several times so that the movement of the pin shaft 4 is not blocked. That is, under the condition of ensuring the concentricity of the through hole of the pin shaft bracket 6, the side plate through hole 101 and the limit plate through hole 201, then weld the pin shaft bracket 6 on the disconnector side plate 1.

[0032] As Figure 7 shown, a plurality of shaft sleeves are provided on the circuit breaker main shaft 10. During assembly, first sleeve the second shaft sleeve 13 on the circuit breaker main shaft 10, and then sleeve the main shaft crank arm 9 on the circuit breaker main shaft 10. At this time, it is necessary to pay attention to the rotation direction of the main shaft crank arm 9 when the circuit breaker 8 is switched on and off. The opening position needs to be below the closing position to ensure that the main shaft crank arm 9 is sleeved in the direction prompted by Figure 1 and then sleeve the first shaft sleeve 12 on the circuit breaker main shaft 10, and finally sleeve the snap ring 11 on the circuit breaker main shaft 10 to lock each shaft sleeve and the main shaft crank arm 9. The snap ring 11 is a well-known technology in the art.

[0033] The working principle of the present invention is:

[0034] One of the "five-prevention" requirements is "preventing the disconnector from being switched on and off under load", that is, when the circuit breaker 8 is in the closed position, the disconnector cannot be operated to switch on and off, and when the circuit breaker 8 is in the open position, the disconnector 1 can be arbitrarily operated to switch on and off.

[0035] When the present invention works, when the main shaft crank arm 9 moves towards the closing position, the end of the brake wire 7 moves upward along with the main shaft crank arm 9, so that the brake wire 7 is in a slack state. And the pin shaft 4 at the other end of the brake wire 7 moves towards the disconnector side plate 1 under the action of the compression spring 5 and drives the brake wire 7 to move together, making the brake wire 7 re-tightened. At this time, the disconnector has two states. One situation is as Figure 5 shown, the disconnector is in the open state, and the pin shaft 4 will pass through the side plate through hole 101 on the disconnector side plate 1 and the limit plate through hole 201 on the limit plate 2, so as to lock the disconnector 1 and prevent it from being closed. The other situation is as Figure 4As shown, the disconnecting switch is in the closed state. The pin shaft 4 will not pass through the through hole 201 of the limit plate 2, but will be located below the limit plate 2 to limit the downward rotation of the limit plate 2, so that the disconnecting switch cannot be switched off.

[0036] As Figure 1 shown, when the main shaft crank arm 9 on the circuit breaker 8 moves from the closed position to the open position, the head end of the brake cable 7 descends along with the main shaft crank arm 9. The pin shaft 4 leaves the through hole 201 of the limit plate through the action of the brake cable 7, but still remains in the side plate through hole 101 on the side plate of the disconnecting switch 1 and no longer limits the limit plate 2. The disconnecting switch 1 can be switched on and off.

[0037] Therefore, when the circuit breaker 8 is in the closed position, the disconnecting switch, whether in the open position or the closed position, will be locked and cannot be switched on and off. When the circuit breaker 8 is in the open position, the disconnecting switch is unlocked and can be switched on and off arbitrarily, thus realizing the requirement of "one prevention" among the "five-preventions", that is, "preventing the disconnecting switch from being switched on and off under load".

Claims

1. An interlocking mechanism for a circuit breaker and a disconnector, characterized in that: It includes a brake wire (7), a pin shaft (4), a compression spring (5), a pin shaft bracket (6) and a limit plate (2). The limit plate (2) is arranged on the main shaft (3) of the disconnector and is located outside the side plate (1) of the disconnector. The pin shaft bracket (6) is arranged inside the side plate (1) of the disconnector. The pin shaft (4) is movably arranged in the pin shaft bracket (6), and one end of the pin shaft (4) passes through the side plate (1) of the disconnector. A compression spring baffle (401) is arranged on the pin shaft (4), and the compression spring (5) is sleeved on the pin shaft (4) between the pin shaft bracket (6) and the compression spring baffle (401). One end of the brake wire (7) is connected to the tail end of the pin shaft (4), and the other end is connected to the main shaft crank arm (9) on the circuit breaker (8). The brake wire (7) is arranged in a brake wire tube (16), and one end of the brake wire tube (16) is fixed by a first wire clamp (14), and the other end is fixed by a second wire clamp (15); One end of the brake wire tube (16) close to the main shaft crank arm (9) is fixed by a first wire clamp (14), and the end of the brake wire tube (16) is connected to a tube bracket (17). A tube bracket through hole (20) is arranged on the tube bracket (17), and a slot hole (19) is arranged on one side of the tube bracket through hole (20) close to the brake wire tube (16). The end of the brake wire tube (16) is provided with a brake wire tube end (18) fixed in the slot hole (19). The brake wire (7) passes through the tube bracket through hole (20) and then is connected to the main shaft crank arm (9); One end of the brake wire tube (16) close to the pin shaft (4) is fixed by a second wire clamp (15), and the movement track of the brake wire (7) is on the same straight line as the movement track of the pin shaft (4); The pin shaft bracket (6) is in a concave shape, wherein the vertical plates on both sides of the pin shaft bracket (6) are welded to the side plate (1) of the disconnector, and a through hole for the pin shaft (4) to pass through is arranged on the middle connecting plate. The compression spring (5) is arranged between the compression spring baffle (401) and the middle connecting plate of the pin shaft bracket (6); The opening position of the main shaft crank arm (9) is below the closing position; When the circuit breaker (8) is in the closed position and the disconnector is in the open state, the pin shaft (4) passes through the limit plate (2). When the circuit breaker (8) is in the closed position and the disconnector is in the closed state, the pin shaft (4) is located below the limit plate (2) and blocks the limit plate (2).

2. The interlocking mechanism for a circuit breaker and a disconnector according to claim 1, characterized in that: The main shaft crank arm (9) is installed on the main shaft (10) of the circuit breaker. A first shaft sleeve (12), a second shaft sleeve (13) and a snap ring (11) are arranged on the main shaft (10) of the circuit breaker. The main shaft crank arm (9) is arranged between the first shaft sleeve (12) and the second shaft sleeve (13), and the main shaft crank arm (9), the first shaft sleeve (12) and the second shaft sleeve (13) are locked by the snap ring (11).

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