Direct current contactor contact dustproof structure
By designing a dustproof structure with dustproof side plates, covers, and connecting plates around the contacts of the DC contactor, the problem of dust accumulation when exposed to airflow is solved, ensuring normal operation of the contactor, preventing short circuits and poor contact, and guaranteeing the continuity of industrial production.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- SHANGHAI AUTOWELL POWER ELECTRONICS CO LTD
- Filing Date
- 2025-05-19
- Publication Date
- 2026-05-29
Smart Images
Figure CN224304635U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to a dustproof structure for DC contactor contacts, belonging to the field of DC contactor technology. Background Technology
[0002] To improve reliability, prevent fault escalation, and facilitate maintenance and recovery, high-voltage frequency converters typically incorporate bypass functionality in their power units. DC contactors are crucial components commonly used to achieve this bypass function. When a power unit experiences performance abnormalities due to overcurrent, overvoltage, or overheating faults, the converter's built-in intelligent control system quickly detects the fault signal and triggers a bypass command through logical judgment. At this point, the DC contactor, with its high-response electromagnetic coil drive mechanism, completes its action within milliseconds, rapidly closing its normally open contacts to establish a low-impedance bypass path. This allows the main circuit current to bypass the faulty unit, ensuring the converter operates in derating mode and preventing a system shutdown due to a single point of failure, effectively guaranteeing the continuity of industrial production.
[0003] While performing the bypass action, the normally closed contacts of the DC contactor simultaneously open, completely isolating the faulty power unit from an electrical perspective. This isolation mechanism is crucial, not only cutting off energy interaction between the faulty unit and the system, but also preventing abnormal voltages and harmonic currents from impacting other normal units, greatly reducing the risk of fault propagation.
[0004] Currently, there are many exposed high-current DC contactors whose contacts are exposed to airflow. In dusty environments, such as steel mills and cement plants, dust easily accumulates on the exposed contactor contacts, causing short circuits or poor contact during engagement, leading to bypass function failure. Directly replacing these normally functioning DC contactors is costly and not entirely necessary, but upgrades and modifications are required to prevent dust accumulation. Summary of the Invention
[0005] The technical problem to be solved by this utility model is to provide a dustproof structure for DC contactor contacts, which solves the problem that some DC contactor contacts are exposed to airflow, which easily leads to dust accumulation on the contacts.
[0006] The technical problem to be solved by this utility model is achieved by the following technical solution:
[0007] A dustproof structure for a DC contactor contact includes a DC contactor contact. The DC contactor contact includes an insulating mounting plate mounted on the upper part of the DC contactor body; a first lower stationary contact fixed to one side of the insulating mounting plate by a first lower mounting plate; a second lower stationary contact fixed to the other side of the insulating mounting plate by a second lower mounting plate; a first upper stationary contact insulated and suspended above the first lower stationary contact by a first upper mounting plate; a second upper stationary contact insulated and suspended above the second lower stationary contact by a second upper mounting plate; an insulating top connecting plate connecting the first and second upper mounting plates together by insulating screws; and a moving contact movably mounted between the upper and lower mounting plates and driven by the electromagnetic coil of the DC contactor body to switch between upper and lower states. The structure also includes:
[0008] The dustproof side plate has a slot on its inner side to prevent interference with the up-and-down movement of the moving contact. The bottom of the dustproof side plate has a limiting strip that protrudes from the inner side and is locked into the lower edge of the insulating mounting plate. The two dustproof side plates are closely attached to the side end faces of the first upper mounting plate, the second upper mounting plate, the first lower mounting plate, and the second lower mounting plate and are set on opposite sides of the DC contactor contact.
[0009] A dust cover is provided with positioning through holes that fit into the insulating screws of the top connecting plate, and the dust cover is fixed to the top of the two dustproof side plates.
[0010] Dustproof connecting plates are provided between the first upper mounting plate and the first lower mounting plate, as well as between the second upper mounting plate and the second lower mounting plate. Each dustproof connecting plate is fixed at both ends to the side end faces of two opposite dustproof side plates. The inner surface of the dustproof connecting plate does not contact the moving contact. The dustproof connecting plate completely covers the side opening space between the first upper mounting plate and the first lower mounting plate, as well as between the second upper mounting plate and the second lower mounting plate.
[0011] Preferably, the dustproof side plate, dustproof cover plate, and dustproof connecting plate are all made of insulating plastic plate or insulating ceramic plate.
[0012] Preferably, the inner surfaces of the dustproof side plate, dustproof cover plate, and dustproof connecting plate are all provided with a rubber layer.
[0013] Preferably, the dustproof cover plate and the dustproof side plate, as well as the dustproof connecting plate and the dustproof side plate, are all fixed together by nylon screws.
[0014] The beneficial effects of this utility model are as follows: a rectangular dustproof enclosure is formed around the DC contactor contacts using a dustproof side plate and a dustproof connecting plate. The dustproof cover plate at the top of the dustproof side plate is pressed together with the top connecting plate to achieve a dustproof effect. The positioning through hole of the dustproof cover plate cooperates with the insulating screw of the top connecting plate, and the limiting strip at the bottom of the dustproof side plate is stuck on the lower edge of the insulating mounting plate to prevent the dustproof structure from falling off. The slot on the inner side of the dustproof side plate is far away from the moving contact to prevent the dustproof structure from interfering with the up and down movement of the moving contact. Attached Figure Description
[0015] Figure 1 This is a schematic diagram of the structure of the present invention after assembly;
[0016] Figure 2 A schematic diagram of a DC contactor with exposed contacts;
[0017] Figure 3 This is a schematic diagram of the exploded structure of this utility model.
[0018] In the picture:
[0019] 1. DC contactor contact; 101. DC contactor body; 102. Insulating mounting plate; 103. First lower mounting plate; 104. First lower stationary contact; 105. Second lower mounting plate; 106. Second lower stationary contact; 107. First upper mounting plate; 108. First upper stationary contact; 109. Second upper mounting plate; 110. Second upper stationary contact; 111. Top connecting plate; 112. Moving contact; 113. Terminal block; 114. Insulating screw;
[0020] 2. Dustproof side panel; 201. Groove; 202. Limiting strip; 203. Screw hole;
[0021] 3. Dustproof cover; 301. Positioning through hole;
[0022] 4. Dustproof connecting plate;
[0023] 5. Nylon screws. Detailed Implementation
[0024] To facilitate a clear understanding of the technical means, creative features, objectives, and effects of this utility model, the following description, in conjunction with specific illustrations, further elaborates on this utility model.
[0025] like Figures 1-3 As shown, the dustproof structure of this DC contactor contact includes: DC contactor contact 1, dustproof side plate 2, dustproof cover plate 3, and dustproof connecting plate 4.
[0026] like Figure 2As shown, the DC contactor contact 1 includes an insulating mounting plate 102 mounted on the upper part of the DC contactor body 101, a first lower stationary contact 104 fixed to one side of the insulating mounting plate 102 by a first lower mounting plate 103, a second lower stationary contact 106 fixed to the other side of the insulating mounting plate 102 by a second lower mounting plate 105, a first upper stationary contact 108 suspended above the first lower stationary contact 104 by a first upper mounting plate 107, a second upper stationary contact 110 suspended above the second lower stationary contact 106 by a second upper mounting plate 109, an insulating top connecting plate 111 connecting the first upper mounting plate 107 and the second upper mounting plate 109 together by an insulating screw 114, and a moving contact 112 movably mounted between the upper and lower mounting plates and driven by the electromagnetic coil of the DC contactor body 101 to switch between upper and lower states.
[0027] The first upper mounting plate 107, the second upper mounting plate 109, the first lower mounting plate 103, and the second lower mounting plate 105 are all made of conductive materials, such as copper conductive plates. The first upper mounting plate 107, the second upper mounting plate 109, the first lower mounting plate 103, and the second lower mounting plate 105 are equipped with corresponding contact terminals 113.
[0028] In the initial state, the upper stationary contacts of the DC contactor (first upper stationary contact 108 and second upper stationary contact 110) are connected and closed by the moving contact 112; the lower contacts (first lower stationary contact 104 and second lower stationary contact 106) are open.
[0029] When the DC contactor receives the state switching control signal, the electromagnetic coil of the DC contactor body 101 drives the moving contact 112 to disconnect the upper stationary contact (first upper stationary contact 108, second upper stationary contact 110) and connect the lower contact (first lower stationary contact 104, second lower stationary contact 106).
[0030] In dusty environments, accumulated dust can cause DC contactors to short-circuit or have poor contact when engaging.
[0031] like Figure 1 , Figure 3 As shown, the inner side of the dustproof side plate 2 is provided with a slot 201 to prevent interference with the up-and-down movement of the moving contact 112. The bottom of the dustproof side plate 2 is provided with a limiting stop 202 that protrudes from the inner side and is engaged with the lower edge of the insulating mounting plate 102. The two dustproof side plates 2 are closely attached to the side end faces of the first upper mounting plate 107, the second upper mounting plate 109, the first lower mounting plate 103, and the second lower mounting plate 105, and are positioned on opposite sides of the DC contactor contact 1. Screw holes 203 are provided on both the upper and side end faces of the dustproof side plate 2.
[0032] The slot 201 on the inner side of the dustproof side plate 2 provides space for the moving contact 112 to move up and down. The moving contact 112 does not contact the dustproof side plate 2, preventing the dustproof structure from interfering with the state switching of the moving contact 112.
[0033] The two dustproof side panels 2 are closely attached to the first upper mounting plate 107, the second upper mounting plate 109, the first lower mounting plate 103, and the second lower mounting plate 105 to prevent dust from entering the interior.
[0034] The dust cover 3 is provided with a positioning through hole 301 that fits onto the insulating screw 114 of the top connecting plate 111. The dust cover 3 is fixed to the top of the two dust cover side plates 2. The dust cover 3 is fixed to the screw hole 203 on the upper end face of the dust cover side plate 2 by nylon screws 5.
[0035] The heads of the insulating screws 114 on the top connecting plate 111 are used as positioning parts, and the positioning through holes 301 on the dust cover 3 are fitted onto the heads of the insulating screws 114. The multiple insulating screws 114 on the heads can prevent the dust cover 3 from moving in any direction on the horizontal plane. In addition, the positioning through holes 301 on the dust cover 3 cooperate with the insulating screws 114 on the top connecting plate 111, and the limiting strip 202 at the bottom of the dust cover 2 is locked onto the lower edge of the insulating mounting plate 102, which restricts the movement of the dustproof structure in the vertical direction, making the entire dustproof structure more robust.
[0036] Dustproof connecting plates 4 are disposed between the first upper mounting plate 107 and the first lower mounting plate 103, and between the second upper mounting plate 109 and the second lower mounting plate 105. Each dustproof connecting plate 4 is fixed at both ends to the side faces of two opposite dustproof side plates 2. The inner surface of the dustproof connecting plate 4 does not contact the moving contact 112. The dustproof connecting plate 4 completely covers the side openings between the first upper mounting plate 107 and the first lower mounting plate 103, and between the second upper mounting plate 109 and the second lower mounting plate 105. The dustproof connecting plates 4 are fixed to the screw holes 203 on the side faces of the dustproof side plates 2 using nylon screws 5.
[0037] The dustproof connecting plate 4 is used to fix the two dustproof side plates 2 on opposite sides, forming a rectangular structure around the DC contactor contact 1. The top is closed by the dustproof cover plate 3, and the bottom is closed by the insulating mounting plate 102. This forms a dustproof structure that can prevent dust from entering the interior from all directions.
[0038] The dustproof connecting plate 4 is installed between the first upper mounting plate 107 and the first lower mounting plate 103, and between the second upper mounting plate 109 and the second lower mounting plate 105, rather than being fixed to the dustproof side plate 2 by being tightly attached to the ends of these mounting plates. This exposes the wiring terminals 113 on the first upper mounting plate 107, the first lower mounting plate 103, the second upper mounting plate 109, and the second lower mounting plate 105 to the outside of the dustproof structure, facilitating wiring while maintaining dustproof performance. The dustproof structure does not interfere with normal wiring operations.
[0039] The dust cover 3 and the dust cover 2, as well as the dust cover connecting plate 4 and the dust cover 2, are all fixed together by nylon screws 5. The nylon screws 5 have insulating and non-conductive properties, making them safer.
[0040] In some embodiments, the dustproof side plate 2, the dustproof cover plate 3, and the dustproof connecting plate 4 are all made of insulating plastic plate or insulating ceramic plate.
[0041] Among them, insulating plastic boards have good insulation properties, are lightweight, low in cost, and easy to install. Insulating plastic boards can be made of materials such as 3240 epoxy boards or FR-4 epoxy glass cloth laminates.
[0042] Insulating ceramic plates can also be used, as they have superior insulation properties.
[0043] In some embodiments, the inner surfaces of the dustproof side plate 2, the dustproof cover plate 3, and the dustproof connecting plate 4 are all provided with a rubber layer (not shown in the figure).
[0044] The rubber layer on the inner side can be pressed tightly during screw fastening to form a more sealed internal space, leaving no gaps between the dustproof panels.
[0045] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of protection claimed by this utility model. The scope of protection of this utility model is defined by the appended claims and their equivalents.
Claims
1. A dustproof structure for a DC contactor contact, comprising a DC contactor contact (1), wherein the DC contactor contact (1) includes an insulating mounting plate (102) mounted on the upper part of a DC contactor body (101), a first lower stationary contact (104) fixed to one side of the insulating mounting plate (102) by a first lower mounting plate (103), a second lower stationary contact (106) fixed to the other side of the insulating mounting plate (102) by a second lower mounting plate (105), and an insulatingly suspended first lower stationary contact by a first upper mounting plate (107). (104) The first upper stationary contact (108) above the second upper stationary contact (110) is insulated and suspended above the second lower stationary contact (106) by the second upper mounting plate (109), the first upper mounting plate (107) and the second upper mounting plate (109) are connected together by an insulating top connecting plate (111), and the moving contact (112) is movably installed between the upper and lower mounting plates and driven by the electromagnetic coil of the DC contactor body (101) to switch between upper and lower states. Also includes: Dustproof side plate (2), the inner side of the dustproof side plate (2) is provided with a slot (201) to prevent interference with the up and down movement of the moving contact (112), the bottom of the dustproof side plate (2) is provided with a limiting strip (202) that protrudes from the inner side and is stuck on the lower edge of the insulating mounting plate (102), the two dustproof side plates (2) are closely attached to the side end faces of the first upper mounting plate (107), the second upper mounting plate (109), the first lower mounting plate (103), and the second lower mounting plate (105) and are provided on the opposite sides of the DC contactor contact (1); Dustproof cover (3), the dustproof cover (3) is provided with a positioning through hole (301) on the insulating screw (114) that fits into the top connecting plate (111), and the dustproof cover (3) is fixed to the top of the two dustproof side plates (2); Dustproof connecting plate (4) is provided between the first upper mounting plate (107) and the first lower mounting plate (103) and between the second upper mounting plate (109) and the second lower mounting plate (105). Each dustproof connecting plate (4) is fixed at both ends to the side end faces of the two opposite dustproof side plates (2). The inner surface of the dustproof connecting plate (4) does not contact the moving contact (112). The dustproof connecting plate (4) completely covers the side opening space between the first upper mounting plate (107) and the first lower mounting plate (103) and between the second upper mounting plate (109) and the second lower mounting plate (105).
2. The dustproof structure for DC contactor contacts according to claim 1, characterized in that, The dustproof side plate (2), dustproof cover plate (3), and dustproof connecting plate (4) are all made of insulating plastic plate or insulating ceramic plate.
3. The dustproof structure for DC contactor contacts according to claim 1, characterized in that, The inner surfaces of the dustproof side plate (2), dustproof cover plate (3), and dustproof connecting plate (4) are all provided with a rubber layer.
4. The dustproof structure for DC contactor contacts according to claim 1, characterized in that, The dust cover (3) and the dust side plate (2), as well as the dust connecting plate (4) and the dust side plate (2), are all fixed by nylon screws (5).