A self-balancing movable contact assembly of a switch and the switch
By adjusting the tapered spring and guide limiting surface in the self-balancing moving contact assembly, the problem of pressure imbalance in high-speed mechanical switches is solved, improving the reliability of the switches and extending the equipment life.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- SHANGHAI LIANGXIN ELECTRICAL CO LTD
- Filing Date
- 2025-05-07
- Publication Date
- 2026-06-16
AI Technical Summary
The existing moving contact structure of high-speed mechanical switches suffers from uneven pressure, leading to differences in contact resistance, localized temperature rise, and decreased reliability.
The self-balancing moving contact assembly is adopted. The moving contact and the drive shaft are self-balanced through the conical spring and the guide limiting surface to ensure that the pressure of the two contact pairs is balanced during the closing process and that the initial concentric state is restored when the circuit is opened.
This achieves pressure equalization of the moving contact during the closing process, avoids local temperature rise, improves the reliability of the switch, and extends the equipment life.
Smart Images
Figure CN224366698U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of switch technology, specifically relating to a self-balancing moving contact of a switch and the switch itself, which is particularly suitable for high-speed mechanical switches. Background Technology
[0002] With the continuous adjustment and improvement of the energy strategy structure, multi-terminal flexible DC transmission has gradually become an important technical means to solve the grid connection of new energy sources. As a protective component in a multi-terminal flexible DC transmission system, the reliability and stability of the DC circuit breaker are extremely important. The control and protection system in a multi-terminal flexible DC transmission system can monitor the status of each component of the DC circuit breaker; therefore, each component of the DC circuit breaker must report status parameters to the upper-level control and protection system both in standby mode and during operation.
[0003] DC circuit breakers typically incorporate high-speed mechanical switches in their main current-carrying branches. In the prior art, Chinese patent CN202411078531.2 discloses a compact ultra-high-speed mechanical switch. Its moving contact combines a traditional drive repulsion disk and conductive contact, reducing the switch's size. It employs a bridge-type contact mechanism to increase the break gap and arc voltage, thereby improving the arc-extinguishing speed. It also uses a graded push-type opening strategy to reduce the mass of moving parts, thus reducing response time and effectively buffering the opening speed. This significantly improves the mechanical life of the ultra-high-speed mechanical switch and offers advantages such as small size, simple structure, and easy functionality. However, this high-speed mechanical switch uses a dual-contact structure, achieving current switching through two contact pairs. Only a single spring on the drive shaft provides the final contact pressure, resulting in the following structural defects:
[0004] (1) Due to the existence of machining tolerances and contact wear differences, a single spring cannot guarantee the pressure balance of the two contact pairs, and uneven pressure distribution will lead to differences in contact resistance, causing local temperature rise.
[0005] (2) During the closing process, the first contact to make contact bears all the pressure, while the contact that makes contact later is prone to bouncing.
[0006] (3) Decreased reliability: The double-contact structure leads to an imbalance in contact pressure during long-term operation, which accelerates contact erosion, reduces the reliability of the switch, and shortens the life of the equipment. Utility Model Content
[0007] The purpose of this invention is to address the shortcomings of existing high-speed mechanical switches by providing a self-balancing moving contact assembly and the high-speed mechanical switch itself, which can automatically adjust the position of the moving contact during the closing process to achieve pressure balance between the two contact pairs.
[0008] Technical solution
[0009] To achieve the above-mentioned technical objectives, this utility model provides a self-balancing moving contact assembly for a switch.
[0010] A self-balancing moving contact assembly for a switch includes a moving contact and a drive shaft. The moving contact is non-contactly mounted on the drive shaft. A self-balancing adjustment device is provided between the moving contact and the drive shaft. The self-balancing adjustment device includes a conical spring or a conical locking washer, located in the connection hole where the moving contact engages with the drive shaft.
[0011] Preferably, a limiting protrusion is provided on the drive shaft below the moving contact, and the limiting protrusion abuts against the lower surface of the moving contact.
[0012] Preferably, the connecting hole at the junction of the moving contact and the drive shaft is provided with a guide limiting surface that matches the self-balancing adjustment device, and the conical spring contacts the guide limiting surface and provides pressure to the guide limiting surface.
[0013] Preferably, the conical spring is made of an elastic metal material.
[0014] Preferably, the conical spring includes a plurality of conical elastic claws evenly distributed along the circumference, and the cone apex angle of the conical spring is 60° to 90°;
[0015] The conical spring has 6-8 conical elastic claws, and the thickness of the conical spring is 0.5-1.2 mm.
[0016] Preferably, the guide limiting surface is the inner wall of the connecting hole, and the inner wall is a cylindrical surface or a conical inclined surface.
[0017] Preferably, the width of the limiting protrusion is greater than the diameter of the hole at the bottom of the connecting hole on the moving contact.
[0018] A switch includes a moving contact assembly as described in any of the preceding claims, wherein the contact pairs of the moving contacts correspond to the stationary contact pairs, one end of a drive shaft passes through a connecting hole on the moving contact and corresponds to a tripping coil, a tripping repulsion disk is arranged between the tripping coil and the upper surface of the moving contact, a closing coil is arranged below the moving contact, and a closing repulsion disk is arranged between the closing coil and the lower surface of the moving contact.
[0019] Preferably, the other end of the drive shaft passes through the closing repulsion disk and the closing coil in sequence.
[0020] Preferably, a retaining ring or nut is mounted on one end of the drive shaft that passes through the connecting hole of the moving contact, and the diameter of the retaining ring or nut is larger than the diameter of the hole at the top of the connecting hole on the moving contact.
[0021] Beneficial effects
[0022] This utility model provides a self-balancing moving contact assembly for a switch and the switch itself. The assembly includes a moving contact and a drive shaft. The moving contact is non-contactly mounted on the drive shaft, and a self-balancing adjustment device is provided between the moving contact and the drive shaft. The self-balancing adjustment device includes a conical spring plate located within a connection hole on the moving contact where it engages with the drive shaft. During closing, the switch automatically adjusts the position of the moving contact to achieve pressure balance between the two contact pairs. During opening, the self-balancing adjustment device restores the initial concentric state, thereby preventing excessive local temperature rise, improving switch reliability, and extending switch lifespan. Attached Figure Description
[0023] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.
[0024] Appendix Figure 1 This is a front view of the moving contact assembly in an embodiment of this utility model;
[0025] Appendix Figure 2 This is a top view of the moving contact assembly in an embodiment of this utility model;
[0026] Appendix Figure 3 It is attached Figure 1 Sectional view along line A.
[0027] Appendix Figure 4 This is a front view of the switch in an embodiment of this utility model;
[0028] Appendix Figure 5 It is attached Figure 4 Sectional view along line B;
[0029] Appendix Figure 6 It is attached Figure 5 Enlarged view of point C in the middle. Detailed Implementation
[0030] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0031] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on the other component or there may be an intermediate component. When a component is considered to be "connected to" another component, it can be directly connected to the other component or there may be an intermediate component present. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application's specification are for illustrative purposes only and do not represent the only possible implementation.
[0032] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.
[0033] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature and the second feature are in indirect contact through an intermediate medium. Furthermore, "above," "over," and "on top" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.
[0034] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in this application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The term "and / or" as used in this application includes any and all combinations of one or more of the associated listed items.
[0035] Example
[0036] As attached Figures 1-3 As shown, a self-balancing moving contact assembly for a switch includes a moving contact 10 and a drive shaft 20. The moving contact 10 is non-contactly mounted on the drive shaft 20, and a self-balancing adjustment device 30 is provided between the moving contact 10 and the drive shaft 20. To prevent the moving contact 10 from sliding axially on the drive shaft 20, a limiting protrusion 21 is provided on the drive shaft 20 below the moving contact 10, and the limiting protrusion 21 abuts against the lower surface of the moving contact 10.
[0037] In detail, the self-balancing adjustment device 30 includes a conical spring 31 or a conical locking washer. In this embodiment, as shown in the attached... Figure 3 As shown, the self-balancing adjustment device 30 is preferably a conical spring plate 31. The connecting hole 12 on the moving contact 10, where it mates with the drive shaft 20, is provided with a guide limiting surface 11 that matches the self-balancing adjustment device 30. The conical spring plate 31 contacts the guide limiting surface 11 and provides pressure to it. The guide limiting surface 11 is the inner wall of the connecting hole 12, which is either a cylindrical surface or a conical inclined surface. The lower diameter of the inner wall is larger than the lower diameter of the conical spring plate 31, allowing the drive shaft 20 to have a clearance within the connecting hole 12. In this embodiment, as shown in the attached... Figure 3 As shown, the guide limiting surface 11 is the inner wall of the connecting hole 12. Preferably, the conical spring piece 31 is made of an elastic metal material. The conical spring piece 31 includes a plurality of conical elastic claws 311 evenly distributed circumferentially, the cone apex angle Q of the conical spring piece 31 is 60° to 90°, and the number of conical elastic claws 311 in the conical spring piece 31 is 6-8. The thickness of the conical spring piece 31 is 0.5-1.2 mm. In this embodiment, the conical spring piece 31 is made of beryllium bronze material, the cone apex angle is 75°, and it can provide a torsional stiffness of 20-50 N·m / rad. Further, the width of the limiting protrusion 21 is greater than the diameter D of the bottom of the connecting hole 12 on the moving contact 10 to ensure that the limiting protrusion 21 abuts against the lower surface of the moving contact 10. The limiting protrusion 21 can be integrally formed with the drive shaft 20. In the initial state, the tapered elastic claw 311 is fully engaged with the guide limiting surface 11, keeping the moving contact 10 concentric with the drive shaft 20. When the contact pressure between the moving contact 10 and the stationary contact pair 40 is unbalanced, the tapered elastic claw 311 generates elastic deformation along the radial direction of the drive shaft 20, allowing the moving contact 10 to deflect and achieve automatic pressure balancing.
[0038] like Figure 1 As shown, the moving contact 10 includes moving contacts 13 at both the left and right ends. Due to severe wear on the right-end moving contact 13, only the left-end moving contact 13 is shown in the attached figure. When the circuit is closed, the left-end moving contact 13 contacts the left-end stationary contact of the stationary contact pair 40. Due to severe wear on the right-end moving contact 13, the contact pressure between the moving contact 10 and the stationary contact pair 40 becomes unbalanced. The drive shaft 20 continues to move upward, and the conical elastic claw 311 generates elastic deformation along the radial direction of the drive shaft 20, allowing the moving contact 10 to deflect with the left-end moving contact 13 as a fulcrum. The moving contact 10 then contacts the right-end stationary contact of the stationary contact pair 40, achieving automatic pressure balancing and ensuring reliable contact between the moving contact 10 and the stationary contact pair 40.
[0039] As attached Figures 4-6This embodiment also provides a switch, including the aforementioned moving contact assembly. The contact pair 101 of the moving contact 10 corresponds to the stationary contact pair 40. One end of the drive shaft 20 passes through the connecting hole 12 on the moving contact 10 and corresponds to the tripping coil 50. A tripping repulsion disk 51 is arranged between the tripping coil 50 and the upper surface of the moving contact 10. A closing coil 60 is arranged below the moving contact 10, and a closing repulsion disk 61 is arranged between the closing coil 60 and the lower surface of the moving contact 10. The other end of the drive shaft 20 passes sequentially through the closing repulsion disk 61 and the closing coil 60. To limit the travel of the moving contact on the drive shaft, a retaining ring 70 or a nut is installed on the end of the drive shaft 20 that passes through the connecting hole 12 of the moving contact 10. The diameter of the retaining ring or nut is larger than the diameter of the hole at the top of the connecting hole 12 on the moving contact 10. The drive shaft 20 can drive the moving contact 10, the closing repulsion disk 61, and the opening repulsion disk 51 to move together.
[0040] This embodiment provides a switch, specifically a high-speed mechanical switch. During the closing phase, the closing coil is energized to generate an upward electromagnetic force. When one end of the moving contact first contacts a corresponding stationary contact, the conical elastic claw 311 expands radially along the drive shaft 20, releasing horizontal and vertical axial degrees of freedom. As the drive shaft continues to move upward, the other end of the moving contact completes contact with another corresponding stationary contact, and the conical elastic claw 311 applies axial pressure along the drive shaft 20. During the opening phase, the opening coil is energized to generate a downward electromagnetic force, and the conical elastic claw 311 guides the moving contact to return to a concentric state during the reset process.
[0041] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.
[0042] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.
Claims
1. A self-balancing moving contact assembly for a switch, comprising a moving contact (10) and a drive shaft (20), characterized in that: The moving contact (10) is non-contactly mounted on the drive shaft (20). A self-balancing adjustment device (30) is provided between the moving contact (10) and the drive shaft (20). The self-balancing adjustment device (30) includes a conical spring (31) or a conical locking washer, located in the connection hole (12) at the point where the moving contact (10) engages with the drive shaft (20).
2. The self-balancing moving contact assembly of the switch as described in claim 1, characterized in that: A limiting protrusion (21) is provided on the drive shaft (20) below the moving contact (10), and the limiting protrusion (21) abuts against the lower surface of the moving contact (10).
3. The self-balancing moving contact assembly of the switch as described in claim 1, characterized in that: The connecting hole (12) at the fitting point of the moving contact (10) and the drive shaft (20) is provided with a guide limiting surface (11) that matches the self-balancing adjustment device (30). The conical spring (31) contacts the guide limiting surface (11) and provides pressure to the guide limiting surface (11).
4. The self-balancing moving contact assembly of the switch as described in claim 3, characterized in that: The conical spring (31) is made of an elastic metal material.
5. The self-balancing moving contact assembly of the switch as described in claim 3, characterized in that: The conical spring (31) includes a plurality of conical elastic claws (311) evenly distributed along the circumference, and the cone apex angle (Q) of the conical spring (31) is 60° to 90°; The tapered elastic claw (311) in the tapered spring (31) has 6-8 tapered elastic claws (311) and the thickness of the tapered spring (31) is 0.5-1.2 mm.
6. The self-balancing moving contact assembly of the switch as described in claim 3, characterized in that: The guide limiting surface (11) is the inner wall of the connecting hole (12), and the inner wall is a cylindrical surface or a conical inclined surface.
7. The self-balancing moving contact assembly of the switch as described in claim 2, characterized in that: The width of the limiting protrusion (21) is greater than the diameter (D) of the bottom of the connecting hole (12) on the moving contact (10).
8. A switch, characterized in that: The moving contact assembly includes any one of claims 1-7, wherein the contact pair (101) of the moving contact (10) corresponds to the stationary contact pair (40), one end of the drive shaft (20) passes through the connecting hole (12) on the moving contact (10) and corresponds to the tripping coil (50), a tripping repulsion disk (51) is arranged between the tripping coil (50) and the upper surface of the moving contact (10), a closing coil (60) is arranged below the moving contact (10), and a closing repulsion disk (61) is arranged between the closing coil (60) and the lower surface of the moving contact (10).
9. The switch as described in claim 8, characterized in that: The other end of the drive shaft (20) passes through the closing repulsion disk (61) and the closing coil (60) in sequence.
10. The switch as claimed in claim 8, characterized in that: The drive shaft (20) has a snap ring (70) or nut installed on one end of the drive shaft (20) that passes through the connecting hole (12) of the moving contact (10). The diameter of the snap ring (70) or nut is larger than the diameter of the top of the connecting hole (12) on the moving contact (10).