A three-position isolated grounding switch for GIS
Through the linkage mechanism of the retaining ring and the sliding block, the retaining ring contacts the stationary contact seat first during the closing process, which pushes the linkage between the positioning rod and the sliding block. This solves the mechanical collision problem caused by the axis deviation of the three-position isolating grounding switch, realizes uniform contact of the contact fingers, and improves the mechanical life and electrical reliability of the equipment.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- JIANGSU WONEN ELECTRIC TECH
- Filing Date
- 2026-03-30
- Publication Date
- 2026-06-26
AI Technical Summary
The existing three-position isolating grounding switch has a rigid mechanical collision between the contact fingers and the stationary contact seat due to axial deviation caused by manufacturing, assembly and long-term operation during the closing operation. This causes wear of the contact fingers and increased contact resistance, which poses a risk of poor connection and affects the safety and reliability of the equipment.
The linkage mechanism of the retaining ring and the sliding block is adopted. The retaining ring first contacts the stationary contact seat, which pushes the positioning rod and the sliding block to correct the centering deviation. This ensures that the contact finger is evenly and stably abutted against the stationary contact seat, eliminating the risk of increased contact resistance and poor connection. The internal spring provides a buffering effect, transforming hard collision into smooth sliding.
It effectively avoids mechanical friction and scratching between the contact finger and the stationary contact, reduces mechanical wear, improves the mechanical life and electrical reliability of the switch, ensures the safety and current carrying capacity of the equipment, and reduces the risk of local overheating caused by loose connections.
Smart Images
Figure CN121938798B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of disconnector technology, and more specifically, to a three-position disconnector grounding switch for GIS. Background Technology
[0002] Currently, solid-insulated ring network switchgear in three-phase AC power grids of urban buildings, shopping malls, public utilities, airports, railways, transportation, coal, chemical, steel, mining enterprises, and power transmission and transformation stations and power plants generally uses insulated switch units. These can be classified according to the insulating medium into solid-insulated disconnect switchgear units, gas-insulated disconnect switchgear units, and vacuum switchgear units. However, existing solid-insulated switchgear with air-isolated, grounding, and three-position disconnecting grounding switches still has certain hidden dangers in operation. Their solid-sealed switch covers are either open or not properly sealed; once the insulating surface is contaminated by foreign objects or moisture, leakage or even short-circuit accidents can occur, endangering operational safety. Furthermore, they lack the ability to close grounding short-circuit currents.
[0003] In existing technology, the closing operation of a three-position isolating grounding switch relies on the drive mechanism directly pushing the moving contact into the stationary contact seat. Due to unavoidable axial deviations caused by manufacturing, assembly, and long-term operation, this process essentially constitutes a hard mechanical collision between the two. This causes the contact finger at the front end of the moving contact seat to easily experience mechanical friction and scratching at the moment of contact with the inner wall of the stationary contact seat. This abnormal friction causes scratches and material wear on the contact surface between the contact finger and the stationary contact seat, and further damages the original flatness of the contact finger surface. Repeated friction and collision make the contact finger surface uneven. When the switch is in the closed operation state, these uneven contact finger surfaces cannot form a full, uniform, and tight fit with the inner wall of the stationary contact seat, but can only form sporadic and unstable physical contact points at the uneven surface protrusions. This directly manifests as the contact finger not being able to uniformly abut against the stationary contact seat, resulting in a significant reduction in the actual effective conductive area. During energized operation, the current is forced to concentrate on these limited contact points, causing the current density at these points to increase sharply, the contact resistance to rise, and abnormally high temperatures to be generated.
[0004] Therefore, there is an urgent need for a three-position isolating grounding switch for GIS to improve the shortcomings of existing technologies. Summary of the Invention
[0005] The purpose of this invention is to provide a three-position isolating grounding switch for GIS. Through a linkage mechanism between a retaining ring and a sliding block, the retaining ring contacts the stationary contact seat first during the closing process. This effectively avoids direct mechanical friction and scratching between the contact fingers and the inner wall of the stationary contact seat due to axial misalignment, protecting the integrity and smoothness of the contact surface. Furthermore, the radial extension of the sliding block actively corrects the alignment deviation, ensuring that all contact fingers can uniformly and stably abut against the stationary contact seat. This eliminates the increased contact resistance and potential for incomplete connections caused by uneven contact pressure, thus solving the problems mentioned in the background art.
[0006] Due to the unavoidable axial deviations caused by manufacturing, assembly and long-term operation, this process essentially constitutes a hard mechanical collision between the two. This causes the contact finger (131) at the front end of the moving contact seat (130) to easily experience mechanical friction and scratching at the moment of contact with the inner wall of the stationary contact seat. This abnormal friction will cause scratches and material wear on the contact surface between the contact finger (131) and the stationary contact seat, and will also damage the original flatness of the surface of the contact finger (131).
[0007] To achieve the above objectives, the present invention provides a three-position isolating grounding switch for GIS, comprising an isolating housing, an insulating support inside the isolating housing, a driving mechanism fixedly connected to one end of the insulating support, a moving contact seat being throttledly connected to the driving mechanism, and a contact finger inside the moving contact seat;
[0008] The isolation housing is provided with a stationary contact and a grounding contact that cooperate with the moving contact. The front end of the moving contact is provided with a round hole and a slot communicating with the round hole. A sliding block is elastically sliding inside the slot.
[0009] A retaining ring is slidably sleeved on the outer wall of the contact end of the finger, and a positioning rod is provided at the rear end of the retaining ring. The end of the positioning rod is elastic and adaptable to slide inside the circular hole, wherein:
[0010] When the retaining ring contacts the end of the inner cavity of the stationary contact seat before the contact finger, and the retaining ring and the contact finger form a closed state that fits against the end of the inner cavity of the stationary contact seat, the positioning rod presses the outer wall of the sliding block against the inner wall of the stationary contact seat.
[0011] In the above technical solution, during the process of moving the moving contact seat to the stationary contact seat to close the circuit, the retaining ring sleeved on the contact finger will contact the stationary contact seat before the moving contact seat and be blocked. This blocking force pushes the positioning rod to move into the round hole inside the moving contact seat. Subsequently, the positioning rod moving inward pushes the sliding block linked with it, so that the sliding block extends outward from the groove on the surface of the moving contact seat.
[0012] Based on this, the baffles fixed on both sides of the sliding block restrict the sliding block within the slot of the moving contact seat, preventing it from coming out of the moving contact seat during the sliding process; and after the closing operation is completed and the driving force disappears, the second spring set between the two baffles can provide an elastic restoring force to make the sliding block automatically retract into the moving contact seat, preparing for the next closing operation.
[0013] In another technical solution, the lower surface of the sliding block near the positioning rod is set as an inclined surface, and the end of the positioning rod that contacts the lower part of the sliding block is also set as an inclined surface, so that when the positioning rod moves inward, it can drive the sliding block to move upward along the inclined surface. A first spring is provided inside the circular hole, with one end abutting against the bottom of the circular hole and the other end abutting against the positioning rod, to provide elastic force for resetting the positioning rod and the retaining ring and buffering force when the retaining ring contacts the stationary contact seat. The retaining ring is made of insulating material and is a replaceable independent component. When the moving contact seat and the stationary contact seat are fully engaged, the sliding block extends under the action of the positioning rod and presses tightly against the inner surface of the stationary contact seat. The inner wall of the retaining ring is provided with a guide groove. The outer surface of the contact finger is provided with a protruding structure that slides with it. The cooperation between the guide groove and the protruding structure is used to restrict the retaining ring to slide only along the axis of the contact finger.
[0014] In this technical solution, during the closing process, when the retaining ring is blocked by the stationary contact seat, it pushes the positioning rod to compress the first spring at its front end and move it into the circular hole. The axial movement of the positioning rod is converted into radial thrust by the inclined surface of the lower surface of the sliding block, driving the sliding block to extend upwards out of the moving contact seat surface and, when fully closed, press tightly against the inner wall of the stationary contact seat to achieve centering. The retaining ring, through the guide groove on its inner wall and the protruding structure on the surface of the contact finger, is restricted to sliding only along the axis of the contact finger, ensuring the linearity and accuracy of the action. The first spring provides both buffering and reset force, while the insulated and replaceable retaining ring design ensures operational safety and ease of maintenance.
[0015] Compared with the prior art, the beneficial effects of the present invention are as follows:
[0016] Through the linkage mechanism of the retaining ring and the sliding block, the retaining ring contacts the stationary contact seat first during the closing process. This not only effectively avoids direct mechanical friction and scratching between the contact fingers and the inner wall of the stationary contact seat due to axial deviation, protecting the integrity and smoothness of the contact surface, but also actively corrects the centering deviation through the radial extension of the sliding block. This ensures that all contact fingers can evenly and stably abut against the stationary contact seat, eliminating the risk of increased contact resistance and poor connection caused by uneven contact pressure. Combined with the buffering effect of the internal spring, the closing action is transformed from a hard collision to a smooth sliding contact, significantly suppressing contact bounce and reducing mechanical wear. This, in turn, improves the overall mechanical life, electrical reliability, and long-term operational safety of the switch.
[0017] The first spring inside the positioning rod acts as a buffer during the initial impact of closing, absorbing some of the impact energy and making the closing process smoother. The pre-alignment mechanism avoids a hard collision between the moving contact and the stationary contact seat when the axis is not aligned, thereby effectively suppressing the bouncing of the contact and reducing the mechanical wear of the mechanism.
[0018] The pre-alignment mechanism ensures the concentricity of the moving and stationary contact seats, allowing the circumferentially arranged contact fingers to make synchronous and stable contact with the stationary contact seat. This ensures uniform contact pressure distribution across all contact fingers, avoiding the problem of some contact fingers experiencing a significant increase in contact resistance due to insufficient pressure. It effectively prevents localized overheating caused by poor contact during equipment operation, improving current carrying capacity and operational reliability. Attached Figure Description
[0019] Figure 1 This is a schematic diagram of the overall structure of the embodiment;
[0020] Figure 2 This is a schematic diagram of the moving contact seat and the stationary contact seat structure in an embodiment;
[0021] Figure 3 This is a cross-sectional structural diagram of the moving contact and the stationary contact in an embodiment;
[0022] Figure 4 This is a partially enlarged structural diagram of an embodiment;
[0023] Figure 5 This is a schematic diagram of the connection structure between the moving contact and the stationary contact in an embodiment.
[0024] The meanings of the labels in the diagram are as follows:
[0025] 100. Isolation housing; 110. Insulating support; 120. Drive mechanism; 130. Moving contact seat; 131. Contact finger; 132. Snap ring; 133. Positioning rod; 134. First spring; 135. Sliding block; 136. Baffle; 137. Second spring; 140. Stationary contact seat; 150. Grounding contact seat. Detailed Implementation
[0026] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0027] Please see Figures 1-5As shown, this embodiment provides a three-position isolating grounding switch for GIS, including an isolating housing 100, an insulating support 110 inside the isolating housing 100, a drive mechanism 120 fixedly connected to one end of the insulating support 110, a moving contact seat 130 being driven by the drive mechanism 120, and a contact finger 131 inside the moving contact seat 130.
[0028] The isolation housing 100 contains a stationary contact 140 and a grounding contact 150 that cooperate with the moving contact 130. The drive mechanism 120, acting as a power source, converts rotary motion into precise linear motion via internal gears, thereby driving the moving contact 130, which is connected to it, to move along the axis. When a closing operation is required, the drive mechanism 120 rotates forward, pushing the moving contact 130 and its internal contact fingers 131 towards the stationary contact 140 until they are fully inserted and reliably in contact, forming a conductive path. When the drive mechanism 120 rotates in reverse, the moving contact 130 withdraws from the stationary contact 140 and moves to an intermediate position where it is not in contact with either, forming a safe insulation break. From this point, the drive mechanism 120 can continue to drive the moving contact 130 past the intermediate position and reliably engage with the grounding contact 150, grounding the line side. This achieves reliable switching between the three positions: isolation, disconnection, and grounding.
[0029] Due to unavoidable axial deviations caused by manufacturing, assembly, and long-term operation, this process essentially constitutes a hard mechanical collision between the two. This causes the contact finger 131 at the front end of the moving contact 130 to easily experience mechanical friction and scratching at the moment of contact with the inner wall of the stationary contact 140. This abnormal friction not only causes scratches and material wear on the contact surface between the contact finger 131 and the stationary contact 140, but also damages the flatness of the surface of the contact finger 131. The front end of the moving contact 130 is provided with a round hole and a groove communicating with the round hole, and a sliding block 135 is elastically sliding inside the groove.
[0030] A retaining ring 132 is slidably sleeved on the outer wall of the contact end of the finger 131. When the drive mechanism 120 pushes the moving contact seat 130 to move towards the stationary contact seat 140, the retaining ring 132 slidably sleeved on the outer wall of the finger 131 will contact the inner wall end of the stationary contact seat 140 before all the fingers 131. This allows the retaining ring 132 to act as a guide, first determining and correcting the relative position between the moving and stationary contact seats 140. The retaining ring 132 slides along a specific axial direction on the outer wall of the finger 131, converting the axial resistance generated by the contact into a driving force that triggers the sliding block 135 to move. This eliminates possible axial deviations before the conductive finger 131 makes substantial electrical contact with the stationary contact seat 140, ensuring that the finger 131 can be inserted into the contact cavity of the stationary contact seat 140.
[0031] A positioning rod 133 is provided at the rear end of the retaining ring 132. The end of the positioning rod 133 is elastic and adaptable to slide inside the circular hole. The axial contact force on the retaining ring 132 is converted into controllable linear motion by the guidance of the positioning rod 133 and the buffering of the first spring 134. When the retaining ring 132 first contacts the end of the stationary contact seat 140 and is axially blocked during the closing process, this reverse force pushes the positioning rod 133 to overcome the resistance of the first spring 134 inside and slide stably into the circular hole. Through the compression of the first spring 134, the initial collision energy is effectively absorbed and buffered, so that the closing action is transformed from a hard impact into a smooth and controllable linear motion. The inward linear motion of the positioning rod 133 provides a reliable action basis for the subsequent driving of the sliding block 135. When the opening operation is performed and the axial pressure is released, the compressed elastic element releases the stored energy, driving the positioning rod 133 and the retaining ring 132 fixed thereto to automatically return to the initial extended position, preparing for the next closing operation.
[0032] When the retaining ring 132 contacts the end of the inner cavity of the stationary contact seat 140 before the contact finger 131, and the retaining ring 132 and the contact finger 131 form a closed state that fits against the end of the inner cavity of the stationary contact seat 140, the positioning rod 133 presses the outer wall of the sliding block 135 against the inner wall of the stationary contact seat 140. During the closing process, when the moving contact seat 130 moves towards the stationary contact seat 140 under the push of the driving mechanism 120, the retaining ring 132, which is made of insulating material and is an independent component, contacts the stationary contact seat 140 first. When the retaining ring 132 and the contact finger 131 move together to the final closed state where they are fully engaged with the inner end of the stationary contact seat 140, the positioning rod 133, which moves inward during this process, continuously presses the outer wall of the sliding block 135 through its end structure. This drives the sliding block 135 to overcome the elastic force of the second spring 137 provided on its two side baffles 136 and extend radially outward from the slot of the moving contact seat 130 until its outer surface is tightly abutting against the inner wall of the stationary contact seat 140, thereby completing the axial centering and radial fixation before the establishment of conductive contact.
[0033] See Figure 2 and Figure 3 As shown, after the closing process is initiated, the moving contact 130 moves towards the stationary contact 140. At this time, the insulated retaining ring 132 first enters and engages with the specially designed pre-alignment cavity at the end of the inner cavity of the stationary contact 140. The main function of the pre-alignment cavity is to guide and receive the retaining ring 132, completing the initial positioning for closing and providing a basis for subsequent precise calibration, while the contact finger 131 has not yet made contact with the contact cavity, which serves as the main conductive circuit.
[0034] As the moving contact seat 130 continues to advance, the axial resistance encountered by the retaining ring 132 at the bottom of the pre-alignment cavity pushes multiple positioning rods 133, arranged in a ring array, to slide synchronously inward along their respective circular holes. The second inclined surface at the end of each positioning rod 133 then contacts the first inclined surface at the bottom of the corresponding sliding block 135. Since the first and second inclined surfaces are parallel, this results in a uniform and stable surface contact, rather than a point or line contact that is prone to wear and jamming. Through this optimized inclined surface engagement, the axial linear motion of all positioning rods 133 is efficiently and smoothly converted into a thrust that drives the radial motion of the sliding block 135.
[0035] Under the action of the inclined plane mechanism, all the ring-shaped array of sliding blocks 135 overcome the resistance of their internal second springs 137 and extend radially outward from the slot of the moving contact seat 130 synchronously and uniformly until they all tightly abut against the inner wall of the stationary contact seat 140. The multi-point synchronous support action forcibly corrects any possible axial deviation between the moving contact seat 130 and the stationary contact seat 140 before the contact finger 131 finally contacts and conducts through the contact cavity, ensuring that the two reach a completely concentric state.
[0036] Only when the sliding block 135 completes radial support and the axis is precisely corrected can the moving contact seat 130 be fully in place, so that the contact finger 131 can synchronously and smoothly achieve full-area electrical contact with the contact cavity of the stationary contact seat 140 without offset or scratching.
[0037] The inward movement of the positioning rod 133 compresses the first spring 134. The compression of this spring effectively absorbs the impact energy of the initial collision, transforming a potential hard mechanical impact into a flexible and controllable buffer stroke. This buffering effect significantly suppresses contact bounce and makes the closing action smoother.
[0038] As the positioning rod 133 slides inward and compresses the first spring 134, it drives the sliding block 135 to extend radially outward from the moving contact seat 130. Multiple sliding blocks 135, distributed in a circular array, move synchronously and eventually come into close contact with the inner surface of the stationary contact seat 140. This action forcibly corrects any potential axial misalignment between the moving contact seat 130 and the stationary contact seat 140 before their conductive contact fingers 131 fully engage, achieving precise mechanical alignment.
[0039] When the opening operation begins, the drive mechanism 120 retracts the moving contact 130. The axial pressure acting on the positioning rod 133 then disappears. At this time, the first spring 134, which has been compressed, releases its stored elastic potential energy, pushing the positioning rod 133 and the retaining ring 132 fixed thereto to move outward, automatically resetting it to its initial extended position, preparing for the next closing operation. Simultaneously, the sliding block 135 retracts into the moving contact 130 under the action of its own second spring 137.
[0040] Throughout the process, the insulated and replaceable retaining ring 132 plays a dual role: functionally, it serves as a pre-contact and force transmission component; in terms of safety and economy, its insulation properties prevent the main circuit current from being conducted to the mechanical mechanism, while its independent replaceable design allows this vulnerable part to be easily replaced after long-term operation, reducing maintenance difficulty and cost.
[0041] In this embodiment, a three-position isolating grounding switch for GIS is used in the following way: First, the drive mechanism 120 converts the rotational motion into linear motion through gear transmission, driving the moving contact 130 to move along the axis. During the closing process, the insulating retaining ring 132 sleeved on the outer wall of the contact finger 131 first contacts the pre-alignment cavity at the end of the inner cavity of the stationary contact 140; the axial force generated by the retaining ring 132 being blocked pushes the rear positioning rod 133 to compress the first spring 134 and slide it into the circular hole. This process effectively absorbs collision energy and achieves buffering and shock absorption. Subsequently, the second inclined surface at the end of the positioning rod 133 and the first inclined surface at the bottom of the sliding block 135, the two inclined surfaces are parallel to form a stable surface contact and interaction, converting the axial motion into radial thrust, driving multiple ring-array distributed sliding blocks 135 to extend outward synchronously and closely abut against the inner wall of the stationary contact 140. Before the contact finger 131 makes contact, the deviation of the axis of the moving and stationary contact 140 is forcibly corrected, and precise alignment is completed. After the sliding block 135 achieves full radial support, the moving contact seat 130 continues to move, ensuring that all contact fingers 131 synchronously and smoothly make full-area electrical contact with the contact cavity of the stationary contact seat 140, ensuring uniform pressure and preventing incomplete connections. During opening, the drive mechanism 120 retracts the moving contact seat 130, the first spring 134 releases energy to push the positioning rod 133 and the retaining ring 132 back to their original positions, and simultaneously, the sliding block 135, under the action of the second spring 137, retracts into the moving contact seat 130 through the baffles 136 on both sides, and all components automatically return to their initial positions. Throughout the process, the insulated and replaceable retaining ring 132 achieves both pre-alignment and electrical isolation, ensuring operational safety and convenient maintenance.
[0042] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely preferred examples and are not intended to limit the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.
Claims
1. A three-position isolating grounding switch for GIS, comprising an isolating housing (100), wherein an insulating support (110) is provided inside the isolating housing (100), a driving mechanism (120) is fixedly connected to one end of the insulating support (110), and a moving contact seat (130) is throttle connected to the driving mechanism (120), wherein a contact finger (131) is provided inside the moving contact seat (130). The isolation housing (100) is provided with a stationary contact (140) and a grounding contact (150) that cooperate with the moving contact (130), characterized in that: The front end of the movable contact seat (130) is provided with a round hole and a slot communicating with the round hole, and a sliding block (135) is elastically slidable inside the slot. The outer wall of the contact end of the contact finger (131) is slidably fitted with a retaining ring (132), and a positioning rod (133) is provided at the rear end of the retaining ring (132). The end of the positioning rod (133) is elastic and adaptable to slide inside the circular hole, wherein: When the retaining ring (132) contacts the end of the inner cavity of the stationary contact seat (140) before the contact finger (131), and the retaining ring (132) and the contact finger (131) form a closed state that fits against the end of the inner cavity of the stationary contact seat (140), the positioning rod (133) presses the outer wall of the sliding block (135) against the inner wall of the stationary contact seat (140); The inner end of the static contact seat (140) is provided with a contact cavity and a pre-alignment cavity; When the circuit is closed, the end of the contact finger (131) is in contact with the contact cavity, and the end of the retaining ring (132) is in pre-alignment cavity; The lower surface portion of the sliding block (135) near the positioning rod (133) is provided as a first inclined surface, and the end of the positioning rod (133) is provided with a second inclined surface that cooperates with the first inclined surface; Furthermore, the first inclined plane is parallel to the second inclined plane to ensure that the two are in surface contact; The circular hole is provided with a first spring (134), one end of which abuts against the bottom of the circular hole and the other end abuts against the positioning rod (133). It is used to provide elastic force to reset the positioning rod (133) and the retaining ring (132), as well as buffer force to buffer the closing impact generated when the retaining ring (132) contacts the stationary contact seat (140). When the moving contact (130) engages with the stationary contact (140), the sliding block (135) extends out under the action of the positioning rod (133) and presses against the inner surface of the stationary contact (140).
2. The three-position isolating grounding switch for GIS according to claim 1, characterized in that: Multiple positioning rods (133), round holes, slots, and sliding blocks (135) are provided. The sliding blocks (135) are arranged in a ring array corresponding to the slots, and the positioning rods (133) are arranged in a ring array corresponding to the round holes.
3. The three-position isolating grounding switch for GIS according to claim 2, characterized in that: The size of the sliding block (135) is adapted to the size of the slot; The sliding block (135) is fixedly connected to baffles (136) on both sides, and a second spring (137) is provided between the baffles (136) and the slot.
4. The three-position isolating grounding switch for GIS according to claim 1, characterized in that: The retaining ring (132) is made of insulating material and is a replaceable, independent component.
5. The three-position isolating grounding switch for GIS according to claim 1, characterized in that: The inner wall of the retaining ring (132) is provided with a guide groove; The outer surface of the finger (131) is provided with a protrusion structure that slides in conjunction with the guide groove. The cooperation between the guide groove and the protrusion structure is used to restrict the retaining ring (132) to slide only along the axis of the finger (131).
6. The three-position isolating grounding switch for GIS according to claim 1, characterized in that: When the retaining ring (132) extends into the pre-alignment cavity, the end of the contact finger (131) has not yet entered the contact cavity, and the size of the contact finger (131) is adapted to the size of the contact cavity.