Transmission structure of direct current contactor and direct current contactor
By designing a DC contactor transmission structure that includes a magnet, a sleeve, an iron core, an armature, a push rod, an insulating cap and a main compression spring, the problem of product failure caused by corrosion slag accumulation in the DC contactor is solved and the use of the DC contactor is improved. longevity effect.
Patent Information
- Application Number
- CN202421082786.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-17
- Publication Date
- 2025-01-21
- Estimated Expiration
- 2034-05-17
AI Technical Summary
In DC contactors, the slag formed by ablation of the contact material is likely to fall into the end surface of the armature, and the accumulation leads to a decrease in the armature stroke, insufficient over-range of the dynamic contact, and a decrease in the over-range pressure, resulting in product failure.
A transmission structure of a DC contactor is designed, including a magnet, a sleeve, an iron core, an armature, a push rod, an insulating cap and a main compression spring. The upper end of the iron core is fixed on the center hole of the magnetic conductor to form a convex stop. The sinking platform of the insulating cap covers the convex stop to prevent corrosion slag from entering the gap between the push rod and the iron core.
It effectively prevents the slag formed by the ablation of the contact material from entering the gap between the push rod and the iron core, avoids accumulation on the armature end face, and improves the service life of the DC contactor.
Smart Images
Figure CN222380501U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of contactors, in particular to a transmission structure of a DC contactor and a DC contactor. Background Art
[0002] In a DC contactor, the breaking current of the load is DC. Since DC current does not have a natural zero point, the contact part needs to be sealed in the ceramic cover cavity and arc extinguished by filling the inside with inert gas. During the breaking process, the contact material burns to form slag, which can only splash and fall into the ceramic cover. When evaluating the life of the DC contactor to the limit, it is often found that the contact material burns too much, and the slag formed is easy to fall from the gap between the push rod and the iron core into the gap between the armature and the iron core, and accumulate on the end face of the armature, resulting in a reduction in the armature stroke, insufficient overtravel of the moving contact, and reduced overtravel pressure, thereby causing product failure.
[0003] During the use of DC contactor products, the slag formed after the contact material is ablated falls into the end face of the armature and accumulates, causing the product's electrical life index to decrease. This is a problem that urgently needs to be solved. Utility Model Content
[0004] The main purpose of the utility model is to provide a transmission structure of a DC contactor and a DC contactor, aiming to solve the above technical problems.
[0005] To achieve the above-mentioned purpose, on the one hand, the utility model proposes a transmission structure of a DC contactor, including a magnetizer and a sleeve fixed on the lower surface of the magnetizer; an iron core and an armature are arranged inside the sleeve; the armature is located below the iron core, and the outer cylindrical surface of the armature forms a sliding fit with the sleeve; the upper end of the iron core is fixedly inserted in the center hole of the magnetizer, and the top surface of the iron core is higher than the top surface of the magnetizer to form a convex stop; a push rod is slidably inserted in the center hole of the iron core; and an insulating cap is fixedly connected to the top of the push rod; an inwardly concave sinker is arranged on the lower end surface of the insulating cap; the lower end of the push rod extends downward and is fixedly connected to the armature; a main compression spring is sleeved on the push rod, and the two ends of the main compression spring respectively abut against the iron core and the armature; the main compression spring is in a compressed energy storage state; when the DC contactor is in a non-powered state, the sinker of the insulating cap covers the convex stop, and the lower end surface of the insulating cap abuts against the top surface of the magnetizer.
[0006] Preferably, the transmission structure also includes a fixed frame, a moving contact, and an over-travel compression spring; the fixed frame is an inverted U-shaped structure formed by bending a plate, and the two side plates of the fixed frame are respectively provided with bayonet holes, and a card block is embedded in the insulating cap; the card block and the bayonet hole are engaged with each other; the moving contact is arranged in the U-shaped groove of the fixed frame; the over-travel compression spring is arranged between the moving contact and the insulating cap, and the over-travel compression spring is in a compressed energy storage state and always exerts an upward force on the moving contact.
[0007] Preferably, the depth of the sink is t1, and the height of the convex stop is t2; both satisfy: t1-t2≥0.3mm.
[0008] Preferably, a boss is integrally formed at the center of the top surface of the insulating cap; and the lower end of the overtravel compression spring is sleeved on the outer cylindrical surface of the boss.
[0009] Preferably, the outer cylindrical surface of the iron core is stepped, including a main section and a mating section located at the top of the main section; the mating section is inserted into the center hole of the magnetic conductor and forms an interference fit; a limiting step is formed between the main section and the mating section and rests against the lower surface of the magnetic conductor.
[0010] Preferably, two annular platforms are provided on the outer cylindrical surface of the top end of the push rod, namely an upper annular platform and a lower annular platform, and a connecting section is provided between the upper annular platform and the lower annular platform; an annular groove is formed on the outer peripheral surface of the connecting section; the upper annular platform and the connecting section are embedded in the insulating cap, and the top surface of the lower annular platform is against the top wall of the sinking platform.
[0011] Preferably, the top of the center hole of the iron core is set as an upper countersunk hole; the hole wall of the upper countersunk hole is an inverted cone; the diameter of the lower end of the upper countersunk hole is larger than the outer diameter of the lower annular table; the upper countersunk hole is used to accommodate the lower annular table; when the lower end surface of the lower annular table abuts against the bottom wall of the upper countersunk hole, the lower end surface of the insulating cap abuts against the top surface of the magnetic conductor.
[0012] Preferably, the bottom of the center hole of the iron core is set as a sinking hole; the center of the armature is provided with a stepped hole, which includes an upper hole section and a lower hole section; the diameter of the upper hole section is larger than the diameter of the lower hole section; the push rod includes a sliding section and a plug-in section located at the bottom end of the sliding section; the diameter of the sliding section is larger than the diameter of the plug-in section; the plug-in section of the push rod is inserted into the lower hole section of the armature and welded and fixed; the outer cylindrical surface of the sliding section of the push rod is slidably matched with the center hole of the iron core; the upper end of the main compression spring is arranged in the sinking hole of the iron core, and the lower end is arranged in the upper hole section of the armature.
[0013] On the other hand, the utility model also provides a DC contactor, which includes the above-mentioned transmission structure and a ceramic cover fixedly mounted on the top surface of the magnetic conductor, and a static contact is arranged on the top wall of the ceramic cover; the lower end of the static contact extends downward into the inner cavity of the ceramic cover, and the moving contact, the fixing frame, and the insulating cap are arranged in the inner cavity of the ceramic cover; the moving contact can contact or disconnect with the static contact.
[0014] Preferably, the ceramic cover and the magnetic conductor are fixedly connected via a sealing ring; the sealing ring and the magnetic conductor are laser-sealed; and the sealing ring and the ceramic cover are brazed.
[0015] Due to the adoption of the above technical solution, the beneficial effects of the utility model are as follows:
[0016] In the utility model, the upper end of the iron core is fixedly inserted into the center hole of the magnetizer, and the top surface of the iron core is higher than the top surface of the magnetizer to form a convex stop. The slag formed by the ablation of the contact material falls on the top surface of the magnetizer. Since the convex stop forms a blocking effect, these slags can be effectively prevented from entering the gap between the push rod and the iron core. In addition, when the DC contactor is in a non-powered state, the sunken platform of the insulating cap covers the convex stop, and the lower end surface of the insulating cap abuts against the top surface of the magnetizer, which can further prevent the slag from entering the gap between the push rod and the iron core. Therefore, the structure of the convex stop and the insulating cap can effectively prevent the slag from entering the end surface of the armature from the inner hole of the iron core, thereby improving the service life of the DC contactor. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.
[0018] Figure 1 A schematic diagram of the structure decomposition of the DC contactor provided by the utility model;
[0019] Figure 2 This is a schematic diagram of the structure decomposition of the DC contactor provided by the utility model after removing the ceramic cover, the sealing ring and the static contact;
[0020] Figure 3 A cross-sectional view of a DC contactor provided by the utility model;
[0021] Figure 4 It is a schematic diagram of the assembly structure formed by the push rod, the insulating cap, and the clamping block in the utility model;
[0022] Figure 5 It is a structural schematic diagram of a convex stopper formed after the magnet and the iron core are assembled in the utility model;
[0023] Figure 6 It is a cross-sectional view of the push rod in the utility model;
[0024] Figure 7 It is a cross-sectional view of the iron core in the utility model;
[0025] Figure 8 It is a cross-sectional view of the armature in the utility model.
[0026] Explanation of the accompanying drawings: 1. Ceramic cover; 2. Moving contact; 3. Fixed frame; 3a. Bayonet; 4. Overtravel compression spring; 5. Push rod; 5a. Lower annular platform; 5b. Connecting section; 5c. Upper annular platform; 5d. Sliding section; 5e. Plug-in section; 5f. First step surface; 6. Iron core; 6a. Upper countersunk hole; 6b. Lower countersunk hole; 6c. Main body section; 6d. Matching section; 6e. Convex stopper; 7. Sleeve; 8. Armature; 8a. Upper hole section; 8b. Lower hole section; 9. Main compression spring; 10. Magnetic conductor; 11. Static contact; 12. Insulating cap; 12a. Countersunk platform; 12b. Boss; 13. Block; 14. Sealing ring. DETAILED DESCRIPTION
[0027] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.
[0028] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back...) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.
[0029] As shown in the accompanying drawings, on the one hand, this embodiment provides a transmission structure of a DC contactor, which includes a magnetic conductor 10 and a sleeve 7 fixed on the lower surface of the magnetic conductor 10; an iron core 6 and an armature 8 are arranged inside the sleeve 7; the armature 8 is located below the iron core 6, and the outer cylindrical surface of the armature 8 forms a sliding fit with the sleeve 7.
[0030] Combination Figure 3 and Figure 5 As shown, the upper end of the iron core 6 is fixedly inserted into the central hole of the magnetizer 10, and the top surface of the iron core 6 is higher than the top surface of the magnetizer 10 to form a convex stop 6e.
[0031] Combination Figure 3 and Figure 4 As shown, a push rod 5 is slidably inserted in the center hole of the iron core 6; and an insulating cap 12 is fixedly connected to the top of the push rod 5; an inwardly concave sink 12a is provided on the lower end surface of the insulating cap 12; the lower end of the push rod 5 extends downward and is fixedly connected to the armature 8; a main compression spring 9 is sleeved on the push rod 5, and the two ends of the main compression spring 9 are respectively against the iron core 6 and the armature 8; the main compression spring 9 is in a compressed energy storage state; the main compression spring 9 always exerts a thrust on the iron core 6 and the armature 8 respectively, so that the two have a tendency to separate from each other.
[0032] Combination Figures 3 to 5 As described above, when the DC contactor is in a non-powered state, that is, the iron core 6 is not energized, under the action of the main compression spring 9, the armature 8 and the iron core 6 are pushed to separate from each other. Since the armature 8 is firmly connected to the push rod 5, the sink 12a of the insulating cap 12 can be tightly covered on the convex stop 6e, and the lower end face A of the insulating cap 12 abuts against the top surface B of the magnetic conductor 10.
[0033] Combination Figures 1 to 3 As shown, the transmission structure also includes a fixed frame 3, a moving contact 2, and an overtravel compression spring 4; the fixed frame 3 is an inverted U-shaped structure formed by bending a plate body, and the two side plates of the fixed frame 3 are respectively provided with a bayonet 3a, and a clamping block 13 is embedded in the insulating cap 12; the clamping block 13 and the bayonet 3a are mutually engaged; the moving contact 2 is arranged in the U-shaped groove of the fixed frame 3, and the two side surfaces of the moving contact 2 form a sliding fit with the U-shaped groove of the fixed frame 3; the overtravel compression spring 4 is arranged between the moving contact 2 and the insulating cap 12, and the overtravel compression spring 4 is in a compressed energy storage state and always forms an upward force on the moving contact 2. By utilizing the structure in which the clamping block 13 and the bayonet 3a are mutually engaged, the fixed frame 3 and the insulating cap 12 are convenient for quick assembly and disassembly.
[0034] Combination Figure 4 and Figure 5 As shown, the depth of the sink 12a is t1, and the height of the convex stop 6e is t2; the two satisfy: t1-t2≥0.3mm. This size limitation can avoid interference between the top of the convex stop 6e and the top wall of the sink 12a when the sink 12a is covered on the convex stop 6e, thereby ensuring that the lower end face A of the insulating cap 12 is against the top face B of the magnetic conductor 10.
[0035] Combination Figures 2 to 4 As shown, a boss 12b is integrally formed at the center of the top surface of the insulating cap 12; the lower end of the overtravel compression spring 4 is sleeved on the outer cylindrical surface of the boss 12b. The boss 12b is provided to cooperate with the lower end of the overtravel compression spring 4 to position the overtravel compression spring 4 and prevent the overtravel compression spring 4 from falling off.
[0036] Combination Figure 5 and Figure 7As shown, the outer cylindrical surface of the core 6 is stepped, including a main body section 6c and a matching section 6d located at the top of the main body section 6c; the matching section 6d is inserted into the center hole of the magnet 10 and forms an interference fit; a limiting step is formed between the main body section 6c and the matching section 6d and abuts against the lower surface of the magnet 10 to form a limiting effect. The upper part of the matching section 6d extends out of the top surface of the magnet (10) to form the convex stop (6e). The interference fit between the matching section 6d and the center hole of the magnet 10 simplifies the assembly structure of the two, and the structure is simple and easy to assemble.
[0037] Combination Figure 4 and Figure 6 As shown, two annular platforms are provided on the outer cylindrical surface of the top end of the push rod 5, namely, an upper annular platform 5c and a lower annular platform 5a, and a connecting section 5b is provided between the upper annular platform 5c and the lower annular platform 5a; an annular groove is formed on the outer peripheral surface of the connecting section 5b; the upper annular platform 5c and the connecting section 5b are embedded in the insulating cap 12, and the top surface of the lower annular platform 5a is against the top wall of the sinking platform 12a. In the embodiment, the insulating cap 12 is made of hard insulating plastic material and is fixed to the top end of the push rod 5 by injection molding. By using the method of embedding the upper annular platform 5c and the connecting section 5b in the insulating cap 12, the firmness of the connection between the push rod 5 and the insulating cap 12 is improved.
[0038] Combination Figure 3 , Figure 4 and Figure 6 , Figure 7 As shown, the top of the center hole of the core 6 is set as an upper countersunk hole 6a; the hole wall of the upper countersunk hole 6a is an inverted cone; the diameter of the lower end of the upper countersunk hole 6a is larger than the outer diameter of the lower annular platform 5a; the upper countersunk hole 6a is used to accommodate the lower annular platform 5a; when the lower end surface of the lower annular platform 5a abuts against the bottom wall of the upper countersunk hole 6a, the lower end surface A of the insulating cap 12 abuts against the top surface B of the magnetizer 10. When the push rod 5 drives the insulating cap 12 to move downward, this structure can protect the lower end surface A of the insulating cap 12 and reduce the force of the lower end surface A of the insulating cap 12 directly impacting the top surface B of the magnetizer 10. Since the hole wall of the upper countersunk hole 6a is an inverted cone, it guides the lower annular platform 5a when it moves downward.
[0039] Combination Figures 3 to 8As shown, the bottom of the center hole of the iron core 6 is set as a sinking hole 6b; the center of the armature 8 is provided with a stepped hole, which includes an upper hole section 8a and a lower hole section 8b; the diameter of the upper hole section 8a is larger than the diameter of the lower hole section 8b; the push rod 5 includes a sliding section 5d and an inserting section 5e located at the bottom end of the sliding section 5d; the diameter of the sliding section 5d is larger than the diameter of the inserting section 5e; the inserting section 5e of the push rod 5 is inserted into the lower hole section 8b of the armature 8 and welded and fixed; the outer cylindrical surface of the sliding section 5d of the push rod 5 is slidably matched with the center hole of the iron core 6; the upper end of the main compression spring 9 is set in the sinking hole 6b of the iron core 6, and the lower end is set in the upper hole section 8a of the armature 8. By using the sinking hole 6b and the upper hole section 8a to accommodate the two ends of the main compression spring 9, the distance between the armature 8 and the iron core 6 can be shortened, making the DC contactor structure more compact. The structure in which the plug-in section 5e of the push rod 5 matches the lower hole section 8b of the armature 8 facilitates the assembly of the two.
[0040] On the other hand, the present embodiment also provides a DC contactor, which includes the above-mentioned transmission structure, and also includes a ceramic cover 1 fixedly mounted on the top surface of the magnetizer 10, and a static contact 11 is arranged on the top wall of the ceramic cover 1; the lower end of the static contact 11 extends downward into the inner cavity of the ceramic cover 1, and the moving contact 2, the fixing frame 3, and the insulating cap 12 are arranged in the inner cavity of the ceramic cover 1; the moving contact 2 can be in contact with or disconnected from the static contact 11. Specifically, the ceramic cover 1 and the magnetizer 10 are fixedly connected by a sealing ring 14; the sealing ring 14 and the magnetizer 10 are laser sealed and welded; the sealing ring 14 and the ceramic cover 1 are brazed.
[0041] The working principle of the above DC contactor is as follows:
[0042] When the DC contactor is energized, the electromagnetic drive system generates a magnetic circuit under the action of the coil, so that the iron core 6 and the armature 8 generate attraction between each other. Since the iron core 6 is fixed, the attraction enables the armature 8 to overcome the elastic force of the main compression spring 9 and move upward toward the iron core 6. Since the push rod 5 is tightly connected to the armature 8, when the armature 8 moves upward, it drives the push rod 5, the insulating cap 12, the fixing frame 3, the moving contact 2, and the overtravel compression spring 4 to move upward together. When the moving contact 2 contacts the static contact 11, the moving push rod 5, the insulating cap 12, and the fixing frame 3 continue to move upward, and the overtravel compression spring 4 is compressed to form an overtravel. When the top surface of the armature 8 fits with the bottom surface of the iron core 6, the movement stops.
[0043] When the DC contactor is powered off, the electromagnetic attraction disappears, and under the action of the main compression spring 9, the armature 8 is pushed downward, thereby driving the push rod 5, the insulating cap 12, the fixing frame 3, the moving contact 2, and the overtravel compression spring 4 to move downward together, the moving contact 2 and the static contact 11 are separated from each other, the overtravel compression spring 4 is reset and pushes the moving contact 2 against the top plate of the fixing frame 3.
[0044] Since the two ends of the static contact 11 are connected with a DC load, the opening and closing of the moving contact 2 and the static contact 11 will inevitably cause the surface of the moving contact 2 and the static contact 11 to be ablated, and the ablated contact material forms slag, which will fall to the top surface B of the magnet 10 under the action of gravity. After the moving and static contacts are opened, the armature 8 is driven by the elastic force of the main compression spring 9 to drive the push rod 5 to move downward at an accelerated speed, thereby driving the insulating cap 12 to accelerate down and cover the convex stop 6e, so that before the slag falls to the top surface B of the magnet 10, the insulating cap 12 has already covered the convex stop 6e.
[0045] When the insulating cap 12 and the magnetizer 10 are separated from each other, the convex stop 6e forms a blocking effect, which can effectively prevent the slag from entering the gap between the push rod 5 and the core 6. When the sink 12a of the insulating cap 12 covers the convex stop 6e, and the lower end surface A of the insulating cap 12 abuts against the top surface B of the magnetizer 10, the slag can be further prevented from entering the gap between the push rod 5 and the core 6. This prevents the slag from entering the end surface of the armature 8 to form an accumulation, causing the armature 8 to be unable to fit with the bottom surface of the core 6 due to the electromagnetic attraction.
[0046] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made under the concept of the present invention using the contents of the specification and drawings of the present invention, or direct / indirect application in other related technical fields are included in the patent protection scope of the present invention.
Claims
1. A transmission structure of a DC contactor, characterized in that: The invention comprises a magnetic conductor (10) and a sleeve (7) fixed on the lower surface of the magnetic conductor (10); an iron core (6) and an armature (8) are arranged inside the sleeve (7); the armature (8) is located below the iron core (6), and the outer cylindrical surface of the armature (8) forms a sliding fit with the sleeve (7); the upper end of the iron core (6) is fixedly inserted into the central hole of the magnetic conductor (10), and the top surface of the iron core (6) is higher than the top surface of the magnetic conductor (10) to form a convex stop (6e); A push rod (5) is slidably inserted in the center hole of the iron core (6); an insulating cap (12) is fixedly connected to the top end of the push rod (5); a concave sink (12a) is provided on the lower end surface of the insulating cap (12); the lower end of the push rod (5) extends downward and is fixedly connected to the armature (8); a main compression spring (9) is sleeved on the push rod (5), and the two ends of the main compression spring (9) are respectively against the iron core (6) and the armature (8); the main compression spring (9) is in a compressed energy storage state; When the DC contactor is in a non-powered state, the sink (12a) of the insulating cap (12) covers the convex stop (6e), and the lower end surface of the insulating cap (12) abuts against the top surface of the magnetic conductor (10).
2. The transmission structure according to claim 1, characterized in that: The invention also comprises a fixing frame (3), a moving contact (2), and an overtravel compression spring (4); the fixing frame (3) is an inverted U-shaped structure formed by bending a plate body, and the two side plates of the fixing frame (3) are respectively provided with a bayonet (3a), and a clamping block (13) is embedded on the insulating cap (12); the clamping block (13) and the bayonet (3a) are mutually clamped; the moving contact (2) is arranged in the U-shaped groove of the fixing frame (3); the overtravel compression spring (4) is arranged between the moving contact (2) and the insulating cap (12), and the overtravel compression spring (4) is in a compressed energy storage state to always form an upward force on the moving contact (2).
3. The transmission structure according to claim 1, characterized in that: The depth of the sink (12a) is t1, and the height of the convex stop (6e) is t2; both satisfy: t1-t2≥0.3mm.
4. The transmission structure according to claim 2, characterized in that: A boss (12b) is integrally formed at the center of the top surface of the insulating cap (12); the lower end of the overtravel compression spring (4) is sleeved on the outer cylindrical surface of the boss (12b).
5. The transmission structure according to claim 1, characterized in that: The outer cylindrical surface of the iron core (6) is stepped, comprising a main section (6c) and a matching section (6d) located at the top of the main section (6c); the matching section (6d) is inserted into the central hole of the magnetic conductor (10) and forms an interference fit; a limiting step is formed between the main section (6c) and the matching section (6d) and abuts against the lower surface of the magnetic conductor (10).
6. The transmission structure according to claim 1, characterized in that: Two annular platforms are arranged on the outer cylindrical surface of the top end of the push rod (5), namely an upper annular platform (5c) and a lower annular platform (5a), and a connecting section (5b) is arranged between the upper annular platform (5c) and the lower annular platform (5a); an annular groove is formed on the outer peripheral surface of the connecting section (5b); the upper annular platform (5c) and the connecting section (5b) are embedded in the insulating cap (12), and the top surface of the lower annular platform (5a) is against the top wall of the sinking platform (12a).
7. The transmission structure according to claim 6, characterized in that: The top of the center hole of the core (6) is arranged as an upper countersunk hole (6a); the hole wall of the upper countersunk hole (6a) is in the shape of an inverted cone; the diameter of the lower end of the upper countersunk hole (6a) is larger than the outer diameter of the lower annular platform (5a); the upper countersunk hole (6a) is used to accommodate the lower annular platform (5a); when the lower end surface of the lower annular platform (5a) abuts against the bottom wall of the upper countersunk hole (6a), the lower end surface of the insulating cap (12) abuts against the top surface of the magnetic conductor (10).
8. The transmission structure according to claim 1, characterized in that: The bottom of the central hole of the iron core (6) is configured as a sinking hole (6b); The center of the armature (8) is provided with a stepped hole, the stepped hole comprising an upper hole section (8a) and a lower hole section (8b); the diameter of the upper hole section (8a) is greater than the diameter of the lower hole section (8b); The push rod (5) comprises a sliding section (5d) and an inserting section (5e) located at the bottom end of the sliding section (5d); the diameter of the sliding section (5d) is larger than the diameter of the inserting section (5e); The plug-in section (5e) of the push rod (5) is inserted into the lower hole section (8b) of the armature (8) and fixed by welding; The outer cylindrical surface of the sliding section (5d) of the push rod (5) is slidably matched with the central hole of the iron core (6); The upper end of the main compression spring (9) is arranged in the sinking hole (6b) of the iron core (6), and the lower end is arranged in the upper hole section (8a) of the armature (8).
9. A DC contactor, characterized in that: The transmission structure comprises the transmission structure as claimed in any one of claims 1 to 8, and further comprises a ceramic cover (1) fixedly mounted on the top surface of the magnetic conductor (10), and a static contact (11) is arranged on the top wall of the ceramic cover (1); the lower end of the static contact (11) extends downward into the inner cavity of the ceramic cover (1), and the moving contact (2), the fixing frame (3), and the insulating cap (12) are arranged in the inner cavity of the ceramic cover (1); the moving contact (2) can be in contact with or disconnected from the static contact (11).
10. A DC contactor according to claim 9, characterized in that: The ceramic cover (1) and the magnetic conductor (10) are fixedly connected via a sealing ring (14); the sealing ring (14) and the magnetic conductor (10) are laser sealed; and the sealing ring (14) and the ceramic cover (1) are brazed.