Grounding switch with locking mechanism

Abstract

The application discloses a grounding switch with a locking mechanism, comprising a mounting base, a movable contact, a static contact and a main drive shaft for driving the movable contact and the static contact to close or open are arranged on the mounting base, at least one group of drive paddles are fixed on the circumferential outer wall of the main drive shaft, the main drive shaft drives the drive paddles to trigger the movable contact to rotate around the axis of the main drive shaft; the mounting base is further provided with a locking mechanism for limiting the rotation of the movable contact around the axis of the main drive shaft, an unlocking push rod is fixed on the drive paddle, and the unlocking push rod is used for releasing the limitation of the locking mechanism on the movable contact when the drive paddle rotates with the main drive shaft; the locking mechanism directly acts on the movable contact through physical interference and limits the freedom of the movable contact at a preset position, when closing or opening is needed, the rotation of the main drive shaft drives the unlocking push rod to move through the drive paddle in advance, the unlocking push rod acts on the locking mechanism in advance to make the locking mechanism disengage, and the unlocking and opening are realized in sequence.

Description

Technical Field

[0001] This application relates to the technical field of grounding switches, and in particular to a grounding switch with a locking mechanism. Background Technology

[0002] Grounding switches are used to establish equipotential between the system and the ground wire during maintenance of downstream circuits, eliminating residual electromotive force to protect the safety of maintenance personnel. In actual operation, the moving and stationary contacts of the grounding switch need to frequently perform the action of connecting or disconnecting. During this process, the instantaneous change in current between the contacts can trigger an electric arc. The electromotive force generated by the arc will directly act on the moving and stationary contacts. The magnitude of this electromotive force will dynamically change with factors such as circuit parameters and contact spacing. When the electromotive force exceeds the rated holding force of the grounding switch mechanism, it will force the moving contact to deviate from the preset working position, thereby causing the grounding switch to automatically close or open without human control, leading to the risk of short circuit in the equipment.

[0003] Existing technologies typically use arc-extinguishing grids to quickly extinguish electric arcs. While this improves the stability and lifespan of the equipment to some extent, it does not specifically address the electrodynamic problems caused by electric arcs. The moving and stationary contacts still have the risk of displacement under the action of electrodynamics, resulting in unresolved safety hazards related to autonomous closing and opening. Summary of the Invention

[0004] To address the issue of the grounding switch automatically closing and opening due to the electrodynamic force generated by the moving and stationary contacts, a grounding switch with a locking mechanism is provided.

[0005] The above-mentioned objective of this application is achieved through the following technical solution: A grounding switch with a locking mechanism includes a mounting base, on which a moving contact, a stationary contact, and a main drive shaft for driving the moving contact and the stationary contact to close or open are provided. At least one set of drive levers is fixed on the circumferential outer wall of the main drive shaft. The rotation of the main drive shaft drives the drive levers to trigger the moving contact to rotate around the axis of the main drive shaft. The mounting base is also provided with a locking mechanism, which is used to restrict the movement of the moving contact around the axis of the main drive shaft. An unlocking push rod is fixed on the drive pawl. When the drive pawl rotates with the main drive shaft, the unlocking push rod is used to release the restriction of the locking mechanism on the moving contact.

[0006] By adopting the above technical solution, when the grounding switch is not in operation, the locking mechanism acts directly on the moving contact through physical interference, restricting its degree of freedom to a preset position. When it is necessary to close or open the circuit, the rotation of the main drive shaft drives the unlocking push rod to move in advance through the drive pawl. The unlocking push rod acts on the locking mechanism in advance to disengage it, realizing unlocking before opening. This not only resists the unexpected displacement caused by the electric arc electrodynamic force in the static state by using hard locking, but also ensures the continuity of the operation process.

[0007] Preferably, the locking mechanism includes a swing arm locking plate connected to the mounting base via a locking plate pivot, and a transmission plate rotatably mounted on the main drive shaft and fixedly connected to the moving contact; a locking pin is provided at one end of the transmission plate near the swing arm locking plate, and a pin locking slot is provided on the swing arm locking plate for the locking pin to be inserted, so as to restrict the rotation of the transmission plate.

[0008] By adopting the above technical solution, the mechanical cooperation of the swing arm locking plate, locking pin and pin locking mouth is used to achieve the limiting. When the electric arc generates electrodynamic force to try to drive the moving contact to rotate, the locking pin is restricted by the side wall of the pin locking mouth and can withstand a large electric arc impact force, ensuring the positional stability of the moving contact in the locked state.

[0009] Preferably, the unlocking push rod is rod-shaped, and an unlocking protrusion is fixed on the end of the swing arm lock plate for sliding adaptation of the unlocking push rod. The sliding surface of the unlocking protrusion is in contact with the outer wall of the unlocking push rod, and is used to drive the swing arm lock plate to deflect around the lock plate axis by sliding and pushing the unlocking push rod.

[0010] By adopting the above technical solution, a rod-shaped unlocking push rod is used in conjunction with the unlocking protrusion at the end of the swing arm lock plate. The unlocking push rod moves in a circular motion with the drive lever, and its outer wall contacts the sliding surface of the unlocking protrusion, forcing the swing arm lock plate to deflect and causing the locking pin to disengage from the pin lock hole. The rotational motion of the main drive shaft is smoothly converted into the swinging unlocking action of the swing arm lock plate. The arc-shaped contact surface reduces frictional resistance and improves the smoothness of the unlocking action.

[0011] Preferably, the mounting base has a guide groove extending along the rotation direction of the swing arm lock plate, and a guide pin is fixed on the swing arm lock plate and slidably embedded in the guide groove. The guide pin and the guide groove are slidably engaged to guide and limit the movement stroke of the swing arm lock plate.

[0012] By adopting the above technical solution, the sliding trajectory of the guide pin in the guide groove determines the rotation path of the swing arm lock plate, preventing the swing arm lock plate from rotating too far during unlocking or resetting, avoiding positioning deviation caused by overload or inertia, and improving the reliability of the mechanical structure.

[0013] Preferably, a reset spring is provided between the swing arm locking plate and the mounting base to connect the two, and the reset spring is used to provide a preload force to reset the swing arm locking plate and engage the locking pin.

[0014] By adopting the above technical solution: the reset spring provides a restoring force to the swing arm locking plate towards the locking position. When the unlocking push rod is removed, the reset spring releases its elastic potential energy, driving the swing arm locking plate to quickly reset, so that the shaft pin lock mouth and the locking shaft pin are re-engaged, ensuring that the locking mechanism can automatically return to its original position after completing one opening operation.

[0015] Preferably, the transmission plate has a sliding groove for the moving contact to slide toward the stationary contact, and the side of the moving contact that abuts against the stationary contact has a pressing contact surface that is inclined toward the stationary contact. The moving contact is provided with a fan-shaped trigger block at the end away from the stationary contact. A fan-shaped driving block is fixed on one end of the driving paddle to abut against the fan-shaped trigger block, so that the moving contact is driven to slide toward the stationary contact by pressing against the fan-shaped trigger block.

[0016] By adopting the above technical solution, when the drive lever rotates to close the circuit, the sector-shaped drive block presses against the sector-shaped trigger block at one end of the moving contact, causing it to slide in the sliding groove toward the stationary contact. The inclined side of the contact presses the contact surface to form a squeezing fit with the stationary contact. The pressure of the pressed contact surface is increased by the inclined surface, which can compensate for the wear of the contact caused by long-term frequent operation and reduce the contact resistance.

[0017] Preferably, each of the drive levers and the swing arm lock plates in the same group is provided with two, and the unlocking push rods on the two drive levers are respectively connected to the ends of the two swing arm lock plates.

[0018] By adopting the above technical solution, the two locking points are symmetrically distributed on both sides of the drive mechanism, making the locking torque distribution on the moving contact more balanced. Even if fatigue occurs on one side of the mechanism, the double locking structure can still maintain sufficient holding force.

[0019] Preferably, the opening width of the pin locking port is greater than the diameter of the locking pin, and the inner wall of the pin locking port is provided with a clearance slope that leaves a gap with the outer wall of the locking pin.

[0020] By adopting the above technical solution, the larger opening width and clearance provide a buffer space for the main drive shaft in the initial stage of rotation, avoiding start-up jamming caused by excessive tightness of the mechanism.

[0021] In summary, this application has at least the following beneficial effects: 1. By setting a locking pin on the transmission plate and engaging it with the pin locking slot of the swing arm locking plate, since the locking state is in a normally closed mode during non-operation, when the electromotive force generated by the arc acts on the moving contact, the mechanical torque generated is directly unloaded to the mounting base by the locking mechanism, eliminating the risk of malfunction caused by the arc electromotive force.

[0022] 2. The unlocking push rod is fixed to the drive paddle on the main drive shaft, so that the unlocking and the drive opening are triggered in the same rotation stroke according to the preset timing. Through the sliding contact between the unlocking push rod and the unlocking protrusion, the circumferential torque of the main drive shaft is converted into the radial deflection force of the swing arm lock plate, which shortens the response path of the closing and opening operation and reduces the mechanical loss of a single operation.

[0023] 3. A sliding groove is opened on the transmission plate and an arc-shaped fan-shaped drive block and a fan-shaped trigger block are set so that the moving contact slides towards the stationary contact after rotation, converting the rotational driving force into a pressing force on the contact surface against the stationary contact, compensating for the mechanical wear of the moving contact after long-term use, and reducing the operation and maintenance cost of power equipment. Attached Figure Description

[0024] Figure 1 This is a three-dimensional structural diagram of a grounding switch; Figure 2 A three-dimensional structural diagram of the drive lever and the transmission plate; Figure 3 A three-dimensional structural diagram of the locking mechanism, drive lever, and transmission plate; Figure 4 for Figure 2 A magnified view of a portion at point A; Figure 5 This is a cross-sectional view of the grounding switch.

[0025] Reference numerals: 1. Mounting base; 11. Guide groove; 2. Main drive shaft; 3. Drive lever; 31. Fan-shaped drive block; 32. Unlocking push rod; 33. Trigger part; 4. Transmission plate; 41. Connecting shaft; 42. Sliding groove; 5. Moving contact; 51. Pressing contact surface; 52. Fan-shaped trigger block; 6. Stationary contact; 7. Locking mechanism; 71. Locking plate pivot; 72. Swing arm locking plate; 721. Shaft pin lock mouth; 722. Leaving slope; 723. Unlocking protrusion; 73. Locking shaft pin; 74. Return spring; 75. Guide pin; 8. Spring assembly; 81. Drive spring; 82. Guide post. Detailed Implementation

[0026] The following section provides a more detailed description, in conjunction with the accompanying diagrams: As attached Figure 1 and attached Figure 2As shown, a grounding switch with a locking mechanism includes a mounting base 1, which provides a mounting reference for internal components. A main drive shaft 2 is rotatably connected to the mounting base 1 via a bearing structure. At least one set of drive levers 3 are engaged on the outer circumferential wall of the main drive shaft 2. The drive levers 3 have two sets of relatively parallel drive levers 3, with two drive levers 3 in each set. The two sets of drive levers 3 are arranged symmetrically at intervals along the axial direction of the main drive shaft 2. Each set of drive levers 3 is axially positioned by a limiting ring (not shown) to prevent axial movement of the drive levers 3 during the rotation of the main drive shaft 2. The inner hole of the drive lever 3 is keyed to the outer wall of the main drive shaft 2, so that the two maintain a rigid transmission relationship without relative slippage in the circumferential direction, thereby ensuring that the torque of the main drive shaft 2 can be transmitted to the drive levers 3.

[0027] As attached Figure 2 and attached Figure 3 As shown, a transmission plate 4 is also rotatably sleeved on the main drive shaft 2. There are three transmission plates 4 here. The three transmission plates 4 are synchronously connected through a connecting shaft 41. Two of the transmission plates 4 are located between two sets of drive paddles 3. The upper ends of the three transmission plates 4 are all bolted with moving contacts 5. Three sets of stationary contacts 6 are fixedly connected to the body of the stationary contact 6. The three sets of moving contacts 5 are respectively abutted against the three sets of stationary contacts 6. An inclined pressing contact surface 51 is integrally formed on the side of the moving contact 5 that abuts against the stationary contact 6. The pressing contact surface 51 is set towards the stationary contact 6.

[0028] The moving contact 5 and the transmission plate 4 are also limited by a locating pin (not shown) to ensure that the moving contact 5 maintains parallelism with the contact surface of the stationary contact 6 during sliding. The transmission plate 4 has a sliding groove 42 on it along the direction perpendicular to the axis of the main drive shaft 2, which allows the locating pin on the moving contact 5 and the connecting shaft 41 to slide. The sliding groove 42 is an oblong hole, and its length direction is consistent with the movement direction of the moving contact 5 toward the stationary contact 6. The two sides of the groove wall of the sliding groove 42 form a surface contact guide fit with the connecting shaft, so that the moving contact 5 can only move along a preset straight line without wobbling. In this way, after the moving contact 5 and the stationary contact 6 wear out after long-term use, the contact area can be increased by sliding the moving contact 5 toward the stationary contact 6.

[0029] A sector-shaped trigger block 52 is integrally fixedly connected to one end of the moving contact 5 away from the stationary contact 6. The sector-shaped trigger block 52 is fan-shaped with an arc-shaped bottom. A sector-shaped drive block 31 is integrally fixedly connected to the drive lever 3. The sector-shaped drive block 31 is fan-shaped with an arc-shaped top. The bottom of the sector-shaped trigger block 52 is aligned with and abuts against the top of the sector-shaped drive block 31. When the main drive shaft 2 drives the drive lever 3 to rotate synchronously, the rotation of the drive lever 3 will abut against the sector-shaped trigger block 52 through the sector-shaped drive block 31, and then drive the moving contact 5 to press against the stationary contact 6 through the sector-shaped trigger block 52. Even if the moving contact 5 and the stationary contact 6 are worn after long-term use, the stability of the connection between the moving contact 5 and the stationary contact 6 can still be ensured by rotating the main drive shaft 2.

[0030] As attached Figure 3 and attached Figure 4 As shown, the mounting base 1 is also provided with a locking mechanism 7. The locking mechanism 7 includes a swing arm locking plate 72 connected to the mounting base 1 via a locking plate pivot 71. The transmission plate 4 is provided with a locking pin 73 at one end near the swing arm locking plate 72. The axis of the locking pin 73 is coaxial with the axis of the main drive shaft 2. The swing arm locking plate 72 is provided with a corresponding pin locking slot 721 for the locking pin 73 to be inserted. When the grounding switch is in the closed state, the locking pin 73 is inserted into the pin locking slot 721 to form a rigid physical limit. When the instantaneous electromotive force generated by the electric arc cannot drive the moving contact 5 and the stationary contact 6 to open.

[0031] The opening width of the pivot pin locking port 721 is designed to be greater than the diameter of the locking pivot pin 73, and a clearance slope 722 is left on the inner wall of one side of the pivot pin locking port 721. The clearance slope 722 is a slope or arc transition surface structure, so that there is a movable gap between the inner wall of one side of the pivot pin locking port 721 and the outer wall of the locking pivot pin 73, avoiding the risk of starting jamming due to the locking pivot pin 73 and the pivot pin locking port 721 being too tight.

[0032] An unlocking push rod 32 is integrally fixedly connected to the drive lever 3. The unlocking push rod 32 has a columnar structure. An unlocking protrusion 723 is integrally fixedly connected to the side of the swing arm lock plate 72 facing the unlocking push rod 32. The protrusion height of the unlocking protrusion 723 gradually changes along the unlocking movement direction. When the main drive shaft 2 rotates and drives the drive lever 3 to rotate synchronously, the unlocking push rod 32 rotates around the axis of the main drive shaft 2 and slides against the unlocking protrusion 723, causing the swing arm lock plate 72 to deflect around the axis of the lock plate pivot 71. The axial length of the unlocking push rod 32 covers the entire working width of the unlocking protrusion 723, so that the two remain in contact during the pushing process, causing the pivot pin lock mouth 721 to rise and disengage from the locking pivot pin 73, so that the restriction can be released before the moving contact 5 rotates.

[0033] The drive lever 3 is also provided with a concave trigger part 33. The trigger part 33 is a concave arc surface. After the main drive shaft 2 is continuously rotated, the trigger part 33 will abut against the outer wall of the locking shaft pin 73 as the drive lever 3 rotates. Then, by pressing the locking shaft pin 73, the moving contact 5 will be disengaged from the stationary contact 6, realizing the sequence of unlocking first and then opening the circuit breaker.

[0034] As attached Figure 2 and attached Figure 3 As shown, a reset spring 74 is also connected between the swing arm locking plate 72 and the mounting base 1. The two ends of the reset spring 74 are respectively hooked between the outer wall of the swing arm locking plate 72 and the mounting base 1. The axis of the reset spring 74 is located outside the rotation trajectory of the swing arm locking plate 72. The reset spring 74 always provides the swing arm locking plate 72 with a restoring torque that tends to the locked position. After the operation is completed, the unlocking push rod 32 is removed, and the reset spring 74 releases elastic potential energy to drive the swing arm locking plate 72 to reset, so that the shaft pin locking mouth 721 and the locking shaft pin 73 are re-engaged, ensuring that the locking mechanism 7 can automatically return to its position after the opening operation is completed.

[0035] To prevent the swing arm locking plate 72 from over-positioning due to inertia during reset or unlocking, a guide groove 11 extending along the rotation direction of the swing arm locking plate 72 is provided on the mounting base 1. The guide groove 11 has an arc-shaped long groove structure. A guide pin 75 is fixedly connected to the side wall of the swing arm locking plate 72 and slides into the guide groove 11. The end of the guide pin 75 is provided with a rounded transition part, so that it has less resistance when sliding in the guide groove 11, which can guide and limit the movement stroke of the swing arm locking plate 72 and avoid positioning deviation caused by overload.

[0036] As attached Figure 5 As shown, the mounting base 1 is also provided with a spring assembly 8, which includes a drive spring 81 and a guide post 82. One end of the drive spring 81 is fixedly connected to the locking plate shaft 71, and the other end of the drive spring 81 is fixedly connected to the locking pin 73. The drive spring 81 is provided with a coaxially arranged guide post 82 inside. The guide post 82 is used to limit the deformation of the drive spring 81 in the radial direction. The drive spring 81 can be synchronously stretched or compressed to store energy during the rotation of the main drive shaft 2. When the drive spring 81 is closed, it releases elastic potential energy to assist in closing. When the drive spring 81 is opened, it stores elastic potential energy. The elastic potential energy released by the drive spring 81 is converted into a boosting torque along the closing direction, which pushes the transmission plate 4 to rotate faster. Through the transmission plate 4, the moving contact 5 moves quickly toward the stationary contact 6, realizing the rapid closing of the contact and reducing the duration of the arc caused by the closing delay.

[0037] The implementation principle of this embodiment: When the grounding switch is in the closed and locked state, the locking pin 73 is embedded in the pin locking mouth 721, so that the inner wall of the pin locking mouth 721 continuously presses the outer wall of the locking pin 73, forming a rigid limiting fit with preload. When the electric arc electrodynamic force or the vibration of the mechanism attempts to drive the moving contact 5 to rotate non-operatingly, the preload can offset part of the impact load and work with the side wall of the pin locking mouth 721 to jointly bear the reverse torque, thereby improving the stability of the position of the moving contact 5 in the locked state. When the main drive shaft 2 rotates and drives the drive paddle 3 to rotate synchronously, the unlocking push rod 32 set on the drive paddle 3 moves in a circle around the axis of the main drive shaft 2. The outer wall of the unlocking push rod 32 gradually slides and abuts against the unlocking protrusion 723 at the end of the swing arm lock plate 72, and applies a radial pushing force to the swing arm lock plate 72, causing the swing arm lock plate 72 to deflect and swing around the axis of the lock plate rotation shaft 71. During this deflection process, the spring structure is further stretched and stored energy. When the swing arm lock plate 72 deflects to the preset unlocking position, the shaft pin lock mouth 721 completely disengages from the outer wall of the locking shaft pin 73, realizing the pre-unlocking before the moving contact 5 rotates. After the unlocking push rod 32 continues to rotate with the drive lever 3 and disengages from the unlocking protrusion 723, the side wall of the swing arm locking plate 72 abuts against the outer wall of the locking pin 73 under the action of the reset spring 74. The trigger part 33 on the drive lever 3 will push against the locking pin 73, thereby synchronously driving the transmission plate 4 and the moving contact 5 to rotate, completing the opening operation.

[0038] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of protection claimed in this application.

Claims

1. A grounding switch with a locking mechanism, comprising a mounting base (1), wherein the mounting base (1) is provided with a moving contact (5), a stationary contact (6), and a main drive shaft (2) for driving the moving contact (5) and the stationary contact (6) to close or open, characterized in that, At least one set of drive paddles (3) are fixed on the circumferential outer wall of the main drive shaft (2). The rotation of the main drive shaft (2) drives the drive paddles (3) to trigger the moving contact (5) to rotate around the axis of the main drive shaft (2). The mounting base (1) is also provided with a locking mechanism (7), which is used to restrict the moving contact (5) from rotating around the axis of the main drive shaft (2). The drive lever (3) is fixed with an unlocking push rod (32). When the drive lever (3) rotates with the main drive shaft (2), the unlocking push rod (32) is used to release the restriction of the locking mechanism (7) on the moving contact (5).

2. A grounding switch with a locking mechanism according to claim 1, characterized in that, The locking mechanism (7) includes a swing arm locking plate (72) connected to the mounting base (1) via a locking plate pivot (71). A transmission plate (4) is rotatably mounted on the main drive shaft (2) and fixedly connected to the moving contact (5). A locking pin (73) is provided at one end of the transmission plate (4) near the swing arm locking plate (72). A pin locking slot (721) is opened on the swing arm locking plate (72) for the locking pin (73) to be inserted, so as to restrict the rotation of the transmission plate (4).

3. A grounding switch with a locking mechanism according to claim 2, characterized in that, The unlocking push rod (32) is rod-shaped, and an unlocking protrusion (723) is fixed on the end of the swing arm lock plate (72) for sliding adaptation of the unlocking push rod (32). The sliding surface of the unlocking protrusion (723) is in contact with the outer wall of the unlocking push rod (32) and is used to drive the swing arm lock plate (72) to deflect around the lock plate pivot (71) by sliding the unlocking push rod (32).

4. A grounding switch with a locking mechanism according to claim 2, characterized in that, The mounting base (1) has a guide groove (11) extending along the rotation direction of the swing arm lock plate (72). The swing arm lock plate (72) has a guide pin (75) that is slidably embedded in the guide groove (11). The guide pin (75) and the guide groove (11) slide to guide and limit the movement stroke of the swing arm lock plate (72).

5. A grounding switch with a locking mechanism according to claim 2, characterized in that, A reset spring (74) is provided between the swing arm lock plate (72) and the mounting base (1) to connect the two. The reset spring (74) is used to provide a preload force to reset the swing arm lock plate (72) and engage the locking pin (73).

6. A grounding switch with a locking mechanism according to claim 2, characterized in that, The transmission plate (4) has a sliding groove (42) for the moving contact (5) to slide toward the stationary contact (6), and the side of the moving contact (5) that abuts against the stationary contact (6) is provided with a pressing contact surface (51) that is inclined toward the stationary contact (6). The moving contact (5) is provided with a fan-shaped trigger block (52) at one end away from the stationary contact (6). A fan-shaped drive block (31) is fixed on one end of the drive lever (3) for abutting against the fan-shaped trigger block (52), so that the moving contact (5) is driven to slide toward the stationary contact (6) by pressing the fan-shaped trigger block (52) with the fan-shaped drive block (31).

7. A grounding switch with a locking mechanism according to claim 2, characterized in that, The drive lever (3) and the swing arm lock plate (72) in the same group are provided in two, and the unlocking push rod (32) on the two drive levers (3) respectively overlaps with the ends of the two swing arm lock plates (72).

8. A grounding switch with a locking mechanism according to claim 2, characterized in that, The opening width of the pin locking opening (721) is greater than the diameter of the locking pin (73), and the inner wall of the pin locking opening (721) is provided with a clearance slope (722) that leaves a gap with the outer wall of the locking pin (73).

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