High voltage DC contactor

Abstract

The present invention discloses a high-voltage direct current contactor, comprising a ceramic assembly, an exhaust pipe, a magnetic conductor, an armature housing, an armature, a restoring spring, a static iron core, a transmission rod, a contact bridge, an overtravel spring, a magnetic conductor insulating gasket, a contact bridge insulating gasket, a shell, a shell bushing, a coil lead wire, a coil assembly and a magnetic steel assembly. The present invention adds an auxiliary contact in addition to two static contacts. When the contactor is connected, the transmission rod drives the contact bridge to contact the two static contacts and an auxiliary contact respectively, and the contacts in the disconnected state are connected. At the same time, the connected auxiliary contacts and the two static contacts can form an auxiliary conduction circuit in pairs, which is used for external interlocking timing control or contactor self-locking and interlocking functions.

Description

Technical Field

[0001] The invention belongs to the technical field of high-voltage direct current contactors, in particular to a contact point structure and a contact bridge structure of a high-voltage direct current contactor. Background Art

[0002] High-voltage DC contactor is an electronic control device with input circuit and output circuit. It is usually used in automatic control circuit. It is actually an "automatic switch" that uses a small current to control a large current. It plays the role of automatic cutoff, safety protection, circuit conversion, etc. in the circuit.

[0003] As a major category of contactors, the existing high-voltage DC contactors are divided into two series, one series is epoxy sealed structure, the other series is ceramic sealed structure, and there are two types of contact forms, one is only one set of bridge-type dynamic main contacts, and the other is a set of bridge-type dynamic main contacts and a set of auxiliary contacts. It is mainly used in the power distribution system of military equipment, and is also used for the main power circuit switching in the fields of new energy electric vehicles, charging piles, energy storage, photovoltaics, power supplies and communications. Summary of the invention

[0004] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a high-voltage DC contactor with auxiliary contacts. By improving the contact bridge, ceramic cavity, welding frame, magnetic conductor and other structural forms, the main contacts and auxiliary contacts are simultaneously turned on when the contactor is in working state. In practical applications, there is no need to connect other relays at the load end for external interlocking timing control or contactor self-locking and interlocking functions, which greatly reduces the production cost of user electrical assembly and can effectively optimize the assembly structure to avoid bloated volume.

[0005] The invention aims to solve the problem of single contact output of the current high-voltage DC contactor and proposes a contactor with auxiliary contacts. The contactor has a simple structure.

[0006] The high-voltage DC contactor with auxiliary contacts of the present invention comprises:

[0007] The shell is made of DuPont nylon and stainless steel shell bushing through in-mold injection molding;

[0008] Bottom plate, the bottom plate is matched with the shell in a snap-fit ​​manner;

[0009] Coil assembly, the coil assembly includes a coil frame, a wound enameled wire and a coil pin, and the coil frame and the coil pin are injection-molded;

[0010] The yoke is a part of the entire contactor magnetic flux circuit, and the coil assembly is assembled inside the yoke;

[0011] The contact system includes: a ceramic assembly, a transmission assembly, and an armature housing; wherein the ceramic assembly is a ceramic part, two static contacts, an auxiliary contact, and a welding frame piece assembled by brazing; wherein the transmission assembly further includes: a contact bridge, a snap ring, a washer, a contact bridge insulating washer, an overtravel spring, a magnetic insulating washer, and a transmission rod; the upper end of the transmission rod is assembled with the magnetic insulating washer, the overtravel spring, the contact bridge, the contact bridge insulating washer, the washer, and the snap ring; and the lower end of the transmission rod is assembled with the armature and the restoring spring;

[0012] The magnetic steel combination includes a magnetic steel bracket and a magnetic steel. The magnetic steel combination is assembled on the outside of the ceramic combination to magnetically blow out and break the arc between the contacts.

[0013] In the high-voltage DC contactor of the present invention, the transmission rod drives the contact bridge to contact two static contacts and one auxiliary contact respectively, and the contacts in a disconnected state are connected.

[0014] Preferably, the auxiliary contact is located on the perpendicular bisector of the line connecting the two stationary contacts;

[0015] Furthermore, the contact bridge is a "T"-shaped structure, and the "T"-shaped structure is an axisymmetric structure.

[0016] Furthermore, the contacts form a conducting circuit, the two static contacts serve as a main load circuit, and the static contacts and the auxiliary contacts form an auxiliary circuit in pairs.

[0017] In the high-voltage DC contactor of the present invention, the ceramic cavity adopts a U-shaped structure, and the auxiliary contact is located at the center of the convex U-shaped structure of the ceramic cavity.

[0018] Furthermore, the "human"-shaped partition raised on the top of the shell physically isolates each contact, and reserves an annular groove on the outside of the contact to inject epoxy glue, fix the shell and internal components, and increase the creepage path distance outside the ceramic parts of each contact, further improving the dielectric withstand voltage performance of the contactor.

[0019] Preferably, the "human" shaped partition is an axisymmetric structure.

[0020] Furthermore, the auxiliary contact is a columnar structure, and the contact end surface adopts a spherical design to ensure reliable contact with the contact bridge.

[0021] Furthermore, the welding frame is formed by stamping Kovar alloy, matches the ceramic cavity, and adopts a convex structure. The magnetic conductor is formed by stamping electrical pure iron, and adopts a convex structure to match the welding frame.

[0022] In the high-voltage direct current contactor of the present invention, the contact system is fully sealed by laser welding, and the cavity is filled with hydrogen and a trace amount of helium.

[0023] Compared with the prior art, the advantages and innovations of the present invention are as follows:

[0024] 1. The present invention provides an auxiliary contact. When the contactor is connected, the static contact and the auxiliary contact are simultaneously turned on. Like the prior art, the two static contacts switch the main load circuit, and the auxiliary contacts and the two static contacts that are turned on at the same time can form an auxiliary conduction circuit in pairs, which is used for external interlocking timing control or contactor self-locking and interlocking functions.

[0025] 2. In the present invention, the ceramic cavity in the ceramic combination adopts a convex-shaped structure design to match the "T"-shaped structure of the contact bridge. The ceramic cavity serves as the movable space of the contact bridge and has a matching shape, which can prevent the contact bridge from shaking and causing the contact position of the contact bridge and the contact point to shift.

[0026] 3. In the present invention, the end face of the auxiliary contact in the ceramic cavity is in the same plane as the end face of the static contact, ensuring the synchronization of each contact during contact. Similarly, the auxiliary end face adopts a spherical design to ensure reliable and stable contact. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a cross-sectional view of a contact combination structure in the background technology;

[0028] Figure 2 This is an external schematic diagram of the contactor of the present invention;

[0029] Figure 3 This is a schematic diagram of the internal structure of the contactor of the present invention;

[0030] Figure 4 It is a schematic diagram of the contact combination structure of the present invention;

[0031] Figure 5 It is a schematic diagram of the structure of the transmission part of the present invention;

[0032] Figure 6 It is a cross-sectional view of the contact combination structure of the present invention;

[0033] Figure 7 It is a schematic diagram of the ceramic composite structure of the present invention;

[0034] Figure 8 This is a schematic diagram of the matching structure of the ceramic combination and the contact bridge of the present invention;

[0035] Fig. 9 This is a schematic diagram of the welding frame structure of the present invention;

[0036] Fig.10 This is a schematic diagram of the contact bridge structure of the present invention;

[0037] Fig.11 This is a schematic diagram of the auxiliary contact structure of the present invention;

[0038] Fig.12 It is a schematic diagram of the structure of the magnetic conductor of the present invention;

[0039] Fig.13 This is a schematic diagram of the shell structure of the present invention;

[0040] Fig.14 It is a schematic diagram of the coil combination structure of the present invention;

[0041] Fig.15 This is a schematic diagram of the magnetic steel assembly structure of the present invention;

[0042] Fig.16 It is a schematic diagram of the magnetic steel assembly structure of the present invention. DETAILED DESCRIPTION

[0043] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments, but the novel transmission mechanism and high-voltage DC contactor thereof of the present invention are not limited to the embodiments.

[0044] At present, with the demand for integration, miniaturization and intelligence in various application fields, especially the requirements put forward by military fields such as aerospace and aviation, the main contacts are not only required to be able to switch high-voltage DC loads, but also required to have an intermediate lead-out function (hereinafter referred to as the intermediate lead-out function is also referred to as the auxiliary contact). The auxiliary contact is led out from the main contact bridge-type dynamic contact bridge. When the main contact is closed, the auxiliary contact is also closed. When the main contact is disconnected, the auxiliary contact is also disconnected. The auxiliary contact is mainly used for circuit self-locking, interlocking or timing control requirements of external circuits.

[0045] The contact part of the high-voltage DC contactor designed according to the technical concept of the present invention includes two static contacts 301, an auxiliary contact 303 and a contact system, the contact system includes a contact bridge 11 and a transmission component, the transmission component includes a snap ring, a washer, a contact bridge insulating washer 14, an overtravel spring 12, a magnetic insulating washer 13 and a transmission rod 10; the upper end of the transmission rod 10 is assembled with the magnetic insulating washer 13, the overtravel spring 12, the contact bridge 11, the contact bridge insulating washer 14, the washer and the snap ring. When the contactor is started, the transmission rod 10 drives the contact bridge 11 to contact the two static contacts 301 and the auxiliary contact 303 respectively, and the contacts in a disconnected state form a conducting circuit.

[0046] See also Figures 1 to 6 As shown, the high-voltage DC contactor in this embodiment mainly includes a ceramic assembly 3, an exhaust pipe 4, a magnetic conductor 5, an armature cover 6, an armature 7, a return spring 8, a static iron core 9, a transmission rod 10, a contact bridge 11, an overtravel spring 12, a magnetic conductor insulating gasket 13, a contact bridge insulating gasket 14, a shell 15, a shell bushing 16, a coil lead wire 17, a coil assembly 18, and a magnetic steel assembly 19.

[0047] See also Figures 5 and 6 As shown, the static iron core 9 is riveted on the magnetizer 5, the transmission rod 10 is installed in the middle of the static iron core 9, and the restoring spring 8 and the armature 7 are installed in the lower end of the transmission rod 10. The magnetizer insulating washer 13 is installed in the upper end of the transmission rod 10 and assembled with the contact bridge 11, the contact bridge insulating washer 14, and the overtravel spring 12. The top is fixed by a clamp ring, and the bottom armature 7 is welded and fixed to the transmission rod 10 by a plasma welding process. The overtravel spring 12 and the contact bridge 11 are installed in the contact bridge fixing frame. The displacement of the overtravel spring 12 (short spring) provides contact pressure to the dynamic and static contacts of the product, and the restoring spring 8 generates a breaking restoring force after the coil is de-energized.

[0048] See also Figure 7 As shown, the ceramic assembly 3 includes a static contact 301, a ceramic cavity 302, an auxiliary contact 303, and a welding frame 304. The static contact 301 and the auxiliary contact 303 are connected to the top of the ceramic cavity 302 by brazing, and the welding frame 304 is connected to the bottom of the ceramic cavity 302 by brazing.

[0049] See also Figures 8 to 9 As shown, the ceramic cavity 302 and the welding frame piece 304 adopt a convex structure, the contact bridge 11 structure adopts a "T"-shaped structure, and the convex cavity of the ceramic cavity 302 is used as the active area. The reinforcing ribs 305 and the rounded corners 306 in the ceramic cavity 302 limit the contact bridge 11, preventing the contact bridge 11 from shaking left or right, resulting in unreliable contact or even no contact.

[0050] See also Fig.10 As shown, the contact bridge 11 includes a first static contact contact part 1101, a second static contact contact part 1102 and an auxiliary contact contact part 1103. When the contactor is powered on, the contact bridge 11 moves toward the contact point along with the transmission rod 10, and reliably contacts and conducts with the three contacts. The circuit formed between the first static contact contact part 1101 and the second static contact contact part 1102 is the main load circuit, and the circuit formed between the first static contact contact part 1101 and the auxiliary contact contact part 1103 is the auxiliary circuit. Similarly, if the current direction is from the second static contact contact part 1102 to the first static contact contact part 1101, the second static contact contact part 1102 and the auxiliary contact contact part 1103 constitute an auxiliary circuit.

[0051] See also Fig.11 The auxiliary contact 303 is a columnar structure. The step 3031 contacts the ceramic cavity 302 and is connected by brazing. The annular groove at the upper end of the columnar structure is the auxiliary contact external winding groove 3032. The lower end of the columnar structure is the auxiliary contact contact part 3033. A spherical design is adopted to ensure reliable contact of the contact.

[0052] See also Fig.12The magnetic conductor 5 is a convex structure, and the welding frame piece 304 of the ceramic assembly 3 is connected to the magnetic conductor 5 through a laser welding process.

[0053] See also Fig.13 The shell 15 is made of DuPont nylon injection molding. The upper end surface of the shell 15 has a herringbone shell partition 1051, which physically isolates the two static contacts 301 and the one auxiliary contact 303. The side surface of the shell 15 is provided with an assembly slot 1502 for assembling with the bottom cover. The bottom ends of the two side surfaces of the shell 15 are also provided with shell mounting holes 1503. The shell mounting holes 1503 and the shell bushing 16 are injection molded.

[0054] See also Fig.14 The coil assembly 18 includes a coil frame 1801, an enameled wire 1802 and a coil pin 1803, wherein the coil frame 1801 and the coil pin 1803 are injection molded in a mold, and the coil lead wire 17 is welded on the coil pin 1803, which is the input end of the contactor.

[0055] See also Figure 15 to Figure 16 The magnetic steel assembly 19 includes a magnetic steel bracket 1901 and a magnetic steel 1902. The magnetic steel assembly 19 is assembled on the outside of the ceramic cavity 302. The magnetic field generated between the magnetic steels 1902 acts on the two static contacts 301. The arc generated by switching between the contacts is deflected by the external magnetic field, so that the arc does not burn between the contacts, and the protective contacts are affected by arc erosion, which reduces the reliability of the product.

[0056] The novel high-voltage DC contactor of the present invention adds an auxiliary contact 303. When the contactor is in the on state, the static contact 301 and the auxiliary contact 303 are simultaneously turned on. As in the prior art, the two static contacts 301 switch the main load circuit, and the auxiliary contact 303 and the two static contacts 301 that are turned on at the same time can form an auxiliary conduction circuit in pairs, which can meet the functions of external interlocking timing control or contactor self-locking and interlocking.

[0057] The ceramic cavity 302, welding frame 304 and magnetic conductor 5 of the novel high-voltage DC contactor of the present invention adopt a convex structure design, and the contact bridge 11 adopts a "Т"-shaped structure. The ceramic cavity 302 serves as the movable space of the contact bridge 11, and its shape fits the contact bridge 11, which can prevent the contact bridge 11 from shaking and causing the contact position of the contact bridge 11 and the contact point to shift.

[0058] The above is only a preferred embodiment of the present invention, and does not constitute any formal limitation to the present invention. Although the present invention has been disclosed as above with preferred examples, it is not intended to limit the present invention. Any technician familiar with the art can make many possible changes and modifications to the technical solution of the present invention using the technical content disclosed above, or modify it into an equivalent equivalent implementation force without departing from the scope of the technical solution of the present invention. Therefore, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention should fall within the scope of protection of the technical solution of the present invention.

Claims

1. High voltage DC contactor, characterized in that: include, Two stationary contacts (301) and one auxiliary contact (303); a contact bridge (11), wherein the contact bridge (11) is in contact with two stationary contacts (301) and an auxiliary contact (303) simultaneously when the high-voltage DC contactor is in an on state, thereby forming a main load circuit and an auxiliary conduction circuit; The contact bridge (11) is a T-shaped sheet structure; The two stationary contacts (301) and the one auxiliary contact (303) are connected to the top of the ceramic cavity (302); the bottom of the ceramic cavity (302) is connected to the welding frame (304); the ceramic cavity (302) is a moving space for the contact bridge; the end surfaces of the two stationary contacts (301) and the one auxiliary contact (303) located in the ceramic cavity (302) are in the same plane; The auxiliary contact (303) is a columnar structure, comprising a step (3031) brazed to the ceramic cavity (302), an auxiliary contact external winding groove (3032) and an auxiliary contact contact portion (3033), and the auxiliary contact contact portion (3033) is a spherical structure.

2. The high voltage DC contactor according to claim 1, characterized in that: The cross section of the contact bridge moving space in the ceramic cavity (302) is in the shape of a convex letter, and the inner and outer contours of the welding frame sheet (304) are in the shape of a convex letter.

3. The high voltage DC contactor according to claim 2, characterized in that: A reinforcing rib (305) and a rounded corner (306) are provided in the contact bridge moving space in the ceramic cavity (302).

4. The high voltage DC contactor according to claim 1, characterized in that: Also includes, A magnetic conductor (5), the magnetic conductor (5) being located below the ceramic cavity (302) and connected to the ceramic cavity (302) via a welding frame sheet (304); A static iron core (9), wherein the static iron core (9) is connected to the magnetic conductor (5); A transmission rod (10), wherein the transmission rod (10) is located in the middle of the static iron core (9); An armature (7) and a return spring (8), wherein the armature (7) is connected to the lower end of the transmission rod (10), and the return spring (8) is sleeved on the lower end of the transmission rod (10) and is located above the armature (7); A magnetic conductor insulating washer (13) and a contact bridge insulating washer (14), wherein the magnetic conductor insulating washer (13) and the contact bridge insulating washer (14) are sequentially connected to the upper end of the transmission rod (10), and the magnetic conductor insulating washer (13) is located above the magnetic conductor (5), and between the magnetic conductor insulating washer (13) and the contact bridge insulating washer (14) is a contact bridge (11) and an overtravel spring (12) mounted on the transmission rod (10).

5. The high voltage DC contactor according to claim 4, characterized in that: It also includes a magnetic steel assembly (19), wherein the magnetic steel assembly (19) includes a magnetic steel support (1901) and a magnetic steel (1902), and the magnetic steel assembly (19) is assembled outside the ceramic cavity (302).

6. The high voltage DC contactor according to claim 4, characterized in that: It also includes a coil assembly (18), wherein the coil assembly (18) includes a coil skeleton (1801), an enameled wire (1802), and a coil plug pin (1803), the coil skeleton (1801) and the coil plug pin (1803) being injection-molded in a mold, and a coil lead wire (17) serving as a contactor input terminal is welded to the coil plug pin (1803).

7. The high voltage DC contactor according to claim 4, characterized in that: It also includes a shell (15), wherein the shell (15) is made of DuPont nylon injection molding, and the upper end of the shell (15) is provided with a shell partition (1051) for isolating two static contacts (301) and one auxiliary contact (303) from each other, and the side surface of the shell (15) is provided with an assembly slot (1502) and a shell mounting hole (1503), and the shell mounting hole (1503) is provided with a shell bushing (16).

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