Isolation knife switch with reliable dynamic and thermal stability of primary and secondary fusion pole-mounted switch

Abstract

The utility model discloses an isolation switch with reliable dynamic thermal stability of a primary and secondary fusion pole-mounted switch in the field of circuit breakers, which comprises a support, a main shaft is arranged on the support and connected with an opening and closing pull arm, a connecting rod is sleeved on the main shaft and hinged with the lower end of an insulating pull rod, and the upper end of the insulating pull rod is connected through a locking mechanism. The locking mechanism is arranged between the pair of movable blades, the front ends of the movable blades are connected through a front clamping structure, the rear ends of the movable blades are connected with the movable contact seat through a rear clamping structure, the bottom of the movable contact seat is connected with a lower electric conductor of an insulating cylinder phase unit, and a static contact gap is reserved between the rear clamping structure and the front ends of the movable blades. The static contact gap is matched with the static contact seat, the locking mechanism is respectively matched with the front clamping structure and the static contact seat, and the static contact seat is installed on a disconnecting link insulator. Therefore, jumping of the movable blade and the static contact seat caused by overlarge instant dynamic stable current is avoided, the mechanical strength of the disconnecting link is remarkably improved, and the dynamic stable performance is good.

Description

Technical Field

[0001] The utility model relates to an isolating knife switch with reliable dynamic thermal stability performance in the field of isolating switches. Background Art

[0002] The maximum short-circuit current that can pass through the dynamic stability current circuit breaker when it is in the closed position is called the dynamic stability current, also known as the rated peak withstand current. It indicates the ability of the circuit breaker to withstand the electromotive force under the action of the short-circuit impact current. The size of this value is determined by the mechanical strength of the conductive and insulating components. The thermal stability current is the maximum current allowed to pass through the circuit breaker within a specified time. It indicates the ability of the circuit breaker to withstand the thermal effect of the short-circuit current. It is expressed as the effective value of the short-circuit current. The thermal stability current for a certain time (1, 2, 4 seconds) specified on the nameplate of the circuit breaker. The thermal stability current refers to the maximum effective value of the periodic component of the current allowed to pass through the circuit breaker in a certain duration when the circuit breaker is in the closed state. At this time, the circuit breaker should not be damaged due to short-term heating.

[0003] For 10kv pole-mounted circuit breakers, the dynamic stability current is the fault current of 20 / 25kA passing through the circuit breaker in the closed state for 4s (thermal stability) and the peak current (50 / 63kA) for 1s (dynamic stability); under this extreme short-circuit fault condition, the mechanical and electrical properties of the short circuit cannot have faults or defects.

[0004] In particular, dynamic stability has particularly high requirements on the mechanical reliability of the pole-mounted switch, while the conventional pole-mounted circuit breaker isolation knife switch in the prior art has low dynamic stability reliability, and the knife switch is prone to popping open when closing the switch, and has poor dynamic stability performance. Utility Model Content

[0005] The utility model aims to provide a primary and secondary fused pole switch with reliable dynamic thermal stability, which solves the problem of low dynamic stability of conventional pole-mounted circuit breaker isolation switches, significantly improves the mechanical strength of the switch and has good dynamic stability.

[0006] To achieve the above-mentioned purpose, the utility model provides a primary and secondary fused pole-mounted switch with reliable dynamic thermal stability, comprising a bracket, a main shaft is arranged on the bracket, the main shaft is connected to a separation and combination pull arm, a connecting rod is sleeved on the main shaft, the connecting rod is hinged to the lower end of the insulating pull rod, the upper end of the insulating pull rod is connected by a locking mechanism, the locking mechanism is arranged between a pair of moving blades, the front ends of the moving blades are connected by a front clamping structure, the rear ends of the moving blades are connected to a moving contact seat by a rear clamping structure, the bottom of the moving contact seat is connected to the conductor under the insulating cylinder phase unit, a static contact gap is left between the front ends of the moving blades of the rear clamping structure, the static contact gap is matched with the static contact seat, the locking mechanism is matched with the front clamping structure and the static contact seat respectively, and the static contact seat is installed on the knife switch insulator.

[0007] Compared with the prior art, the beneficial effect of the utility model lies in that, when closing the switch, the main shaft is rotated by the opening and closing pull arm, so that the connecting rod drives the insulating pull rod to swing, and the insulating pull rod drives the moving blade to swing. The front end of the moving blade is plugged into the static contact seat, and the static contact is clamped by the front clamping structure. At the same time, the static contact seat is locked through the locking mechanism to avoid the moving blade and the static contact seat from jumping apart due to the instantaneous excessive dynamic stability current. The mechanical strength of the knife switch is significantly improved, and the dynamic stability performance is good.

[0008] As a further improvement of the present invention, the locking mechanism includes a locking pin, a locking pin shaft is passed through the rear end of the locking pin, both ends of the locking pin shaft extend out of a waist-shaped groove, the waist-shaped groove is opened in the middle of the movable blade, the outer side of the waist-shaped groove is matched with a limit ring, both ends of the locking pin shaft extend out of the limit ring and are passed through with pins, and the front end of the locking pin passes through the front clamping structure and matches the pin hole opened on the static contact seat.

[0009] In this way, the insulating pull rod swings, and the moving blade is driven to swing toward the static contact seat through the locking pin. At the same time, the locking pin will move forward along the waist groove, thereby driving the locking pin to move forward and finally insert into the pin hole on the static contact seat. In this way, the locking pin will lock the moving blade and the static contact seat to ensure that the dynamic stability current is too large and will not cause the moving blade and the static contact seat to bounce apart, thereby improving the mechanical strength of the knife switch. The limit ring and the pin are used to install and limit the locking pin. When opening the switch, the main shaft is rotated in the opposite direction, so that the locking pin will move backward along the waist groove, thereby separating the locking pin from the static contact seat. Continue to rotate the main shaft, and the moving blade will separate from the static contact seat to realize the opening operation.

[0010] As a further improvement of the utility model, the front clamping structure includes a front clamping pin and a pair of blade pressure plates, the blade pressure plates are respectively arranged on the outer sides of a pair of moving blades, the front clamping pin passes through the front end of the moving blade and the blade pressure plate, the two ends of the front clamping pin are equipped with front clamping nuts, the two ends of the front clamping pin are sleeved with static contact compression springs, the static contact compression springs are arranged between the front clamping nut and the blade pressure plate, and the front end of the locking pin passes through the front clamping pin.

[0011] When closing the switch, the static contact gap at the front end of the moving blade contacts the static contact seat, and the static contact seat is inserted through the contact gap to squeeze the moving blade to both sides. In this way, the static contact compression spring applies pressure to the moving blade in the opposite direction, so that the moving blade can clamp the static contact seat. The static contact seat is subjected to a more balanced force and cooperates with the locking pin to lock and fix the static contact seat.

[0012] As a further improvement of the present invention, the rear clamping structure includes a rear clamping pin, which passes through the rear ends of a pair of moving blades and is equipped with a rear clamping nut. One end of the rear clamping pin is sleeved with a moving contact compression spring, which is arranged between the rear clamping nut and the moving blade. The moving contact seat is sleeved on the part of the rear clamping pin between the moving blades.

[0013] In this way, the rear end of the moving blade is clamped and fixed to the moving contact seat by the moving contact compression spring, so that the moving contact seat can always be connected to the moving blade, ensuring that the moving blade is in good contact with the conductor under the insulating cylinder phase unit through the moving contact seat. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of the closing structure of the utility model.

[0015] Figure 2 It is a schematic diagram of the gate-breaking structure of the utility model.

[0016] Figure 3 It is a top view of the utility model.

[0017] Figure 4 for Figure 2 A partial enlarged view of point A in the middle.

[0018] Figure 5 for Figure 3 A partial enlarged view of point B in the middle.

[0019] Figure 6 for Figure 3 A partial enlarged view of point C in the middle.

[0020] Figure 7 This is a cross-sectional view of the locking mechanism of the utility model.

[0021] Among them, 1 bracket, 2 main shaft, 3 opening and closing pull arm, 4 insulating tube phase unit lower conductor, 5 knife switch insulator, 6 static contact seat, 7 insulating pull rod, 8 connecting rod, 9 moving blade, 10 pin, 11 limit ring, 12 locking pin, 13 blade pressure plate, 14 contact compression spring, 15 front clamping nut, 16 locking pin, 17 front clamping pin, 18 rear clamping pin, 19 rear clamping nut, 20 moving contact seat, 21 moving contact compression spring, 22 waist groove. DETAILED DESCRIPTION

[0022] The utility model is further described below in conjunction with the accompanying drawings:

[0023] like Figure 1-7The illustrated is a primary-secondary fused pole-mounted switch with reliable dynamic thermal stability, comprising a bracket 1, on which a main shaft 2 is arranged, the main shaft 2 is connected to a separation and combination pull arm 3, and is characterized in that: a connecting rod 8 is sleeved on the main shaft 2, the connecting rod 8 is hinged to the lower end of an insulating pull rod 7, the upper end of the insulating pull rod 7 is connected by a locking mechanism, the locking mechanism is arranged between a pair of moving blades 9, the front ends of the moving blades 9 are connected by a front clamping structure, the rear ends of the moving blades 9 are connected to a moving contact seat 20 by a rear clamping structure, the bottom of the moving contact seat 20 is connected to the lower conductor 4 of the insulating cylinder phase unit, a static contact gap is left between the front ends of the moving blades 9 of the rear clamping structure, the static contact gap is matched with the static contact seat 6, the locking mechanism is matched with the front clamping structure and the static contact seat 6 respectively, and the static contact seat 6 is installed on the knife switch insulator 5.

[0024] The locking mechanism includes a locking pin 16, a locking pin 12 is passed through the rear end of the locking pin 16, both ends of the locking pin 12 extend out of a waist-shaped groove 22, the waist-shaped groove 22 is opened in the middle of the movable blade 9, the outer side of the waist-shaped groove 22 is matched with a limit ring 11, both ends of the locking pin 12 extend out of the limit ring 11 and are passed through a pin 10, and the front end of the locking pin 16 passes through the front clamping structure and matches the pin hole opened on the static contact seat 6.

[0025] The front clamping structure includes a front clamping pin 17 and a pair of blade pressure plates 13. The blade pressure plates 13 are respectively arranged on the outer sides of a pair of moving blades 9. The front clamping pin 17 passes through the front end of the moving blade 9 and the blade pressure plate 13. The two ends of the front clamping pin 17 are equipped with front clamping nuts 15. The two ends of the front clamping pin 17 are sleeved with static contact compression springs 14. The static contact compression spring 14 is arranged between the front clamping nut 15 and the blade pressure plate 13. The front end of the locking pin 16 passes through the front clamping pin 17.

[0026] The rear clamping structure includes a rear clamping pin 18, which passes through the rear ends of a pair of moving blades 9 and is equipped with a rear clamping nut 19. One end of the rear clamping pin 18 is sleeved with a moving contact compression spring 21, and the moving contact compression spring 21 is arranged between the rear clamping nut 19 and the moving blade 9. The moving contact seat 20 is sleeved on the part of the rear clamping pin 18 between the moving blades 9.

[0027] In the utility model, when the moving contact seat 20 is closed, the main shaft 2 is rotated by the opening and closing pull arm 3, so that the connecting rod 8 drives the insulating pull rod 7 to swing. Since the locking pin shaft 12 is connected to the insulating pull rod 7, the locking pin shaft 12 drives a pair of moving blades 9 to swing toward the stationary contact seat 6. At the same time, the locking pin shaft 12 will move forward along the waist groove 22, thereby driving the locking pin 16 to move forward and finally insert into the pin hole on the stationary contact seat 6. In this way, the locking pin 16 will connect the moving blade 9 with the stationary contact seat 6. It is locked and fixed, and the static contact gap at the front end of the moving blade 9 contacts the static contact seat 6, and finally the static contact seat 6 is inserted through the contact gap to squeeze the moving blade 9 to both sides, so that the static contact compression spring 14 applies pressure to the moving blade 9 in the opposite direction, so that the moving blade 9 can clamp the static contact seat 6, and the static contact seat 6 is more evenly stressed, and cooperates with the locking pin 16 to lock and fix the static contact seat 6 to ensure that the dynamic stability current is too large and will not cause the moving blade 9 and the static contact seat 6 to jump apart, thereby improving the mechanical strength of the knife switch.

[0028] When opening the switch, the opening and closing pull arm 3 is rotated in the opposite direction, thereby rotating the main shaft 2 in the opposite direction, so that the locking pin shaft 12 will move backward along the waist groove 22, thereby driving the locking latch 16 to move backward and then separate from the static contact seat 6. Continue to rotate the main shaft 2, then the movable blade 9 will separate from the static contact seat 6, and the opening operation is realized.

[0029] Regardless of the opening or closing operation, the moving contact seat 20 is firmly pressed against the rear end of the moving blade 9 by the moving contact compression spring 21, ensuring that the moving blade 9 is in good contact with the conductor 4 under the insulating cylinder phase unit.

[0030] The utility model solves the problem of low reliability of dynamic stability performance of isolating knife switch of conventional pole-mounted circuit breaker. When the isolating knife is in the closed state, the insulating pull rod 7 pushes the locking pin 16 to insert into the pin hole of the static contact seat 6, and cooperates with the static contact compression spring 14 and the blade pressure plate 13, so that in this state, the dynamic blade 9 and the static contact seat 6 are in a locked state, thereby significantly improving the mechanical strength of the knife switch and improving the dynamic stability performance.

[0031] The present utility model is not limited to the above-mentioned embodiments. On the basis of the technical solution disclosed herein, technicians in this field can make some substitutions and deformations to some technical features therein according to the disclosed technical content without creative labor, and these substitutions and deformations are all within the protection scope of the present utility model.

Claims

1. A primary and secondary fusion column switch with reliable dynamic thermal stability, comprising a bracket, a main shaft is arranged on the bracket, and the main shaft is connected to a separation and combination pull arm, characterized in that: A connecting rod is sleeved on the main shaft, and the connecting rod is hinged to the lower end of the insulating pull rod. The upper end of the insulating pull rod is connected by a locking mechanism. The locking mechanism is arranged between a pair of moving blades. The front ends of the moving blades are connected by a front clamping structure, and the rear ends of the moving blades are connected to the moving contact seat by a rear clamping structure. The bottom of the moving contact seat is connected to the conductor under the insulating cylinder phase unit. A static contact gap is left between the front ends of the moving blades of the rear clamping structure, and the static contact gap is matched with the static contact seat. The locking mechanism is matched with the front clamping structure and the static contact seat respectively, and the static contact seat is installed on the knife switch insulator.

2. According to claim 1, a primary and secondary fusion column switch with reliable dynamic thermal stability isolating knife switch, characterized in that: The locking mechanism includes a locking pin, a locking pin shaft is passed through the rear end of the locking pin, both ends of the locking pin shaft extend out of a waist-shaped groove, the waist-shaped groove is arranged in the middle of the movable blade, the outer side of the waist-shaped groove is matched with a limit ring, both ends of the locking pin shaft extend out of the limit ring and are passed through with a pin, and the front end of the locking pin passes through the front clamping structure and matches the pin hole arranged on the static contact seat.

3. According to claim 2, a primary and secondary fusion column switch with reliable dynamic thermal stability isolating knife switch, characterized in that: The front clamping structure includes a front clamping pin and a pair of blade pressure plates. The blade pressure plates are respectively arranged on the outer sides of a pair of moving blades. The front clamping pin passes through the front end of the moving blade and the blade pressure plate. Both ends of the front clamping pin are equipped with front clamping nuts. Both ends of the front clamping pin are sleeved with static contact compression springs. The static contact compression spring is arranged between the front clamping nut and the blade pressure plate. The front end of the locking pin passes through the front clamping pin.

4. According to claim 3, a primary and secondary fused column mounted switch with reliable dynamic thermal stability isolating knife switch, characterized in that: The rear clamping structure includes a rear clamping pin, which passes through the rear ends of a pair of moving blades and is equipped with a rear clamping nut. One end of the rear clamping pin is sleeved with a moving contact compression spring, which is arranged between the rear clamping nut and the moving blade. The moving contact seat is sleeved on the part of the rear clamping pin between the moving blades.

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