DC contactor

Abstract

The utility model discloses a direct-current contactor, which comprises a magnetic pole piece, a push rod group penetrating through the magnetic pole piece and a movable contact piece arranged on the push rod group, and is characterized in that the push rod group is used for pushing the movable contact piece to move so as to realize the on-off function of the direct-current contactor; the magnetic pole piece is provided with a first limiting feature, the push rod set is provided with a second limiting feature, and the first limiting feature and the second limiting feature are used in cooperation to limit rotation of the push rod set. According to the utility model, the first limiting feature arranged on the magnetic pole piece and the second limiting feature arranged on the push rod group are matched for use to restrain the rotational degree of freedom of the push rod group, so that the problem of difficult forming caused by ceramic ribs can be solved, and meanwhile, the occupation of the internal space of the ceramic cover is reduced; therefore, the interior of the ceramic cover has more abundant space for arc discharge and short circuit protection, and the reliability of the DC contactor in the aspect of electrical performance is improved.

Description

Technical Field

[0001] This utility model relates to the field of contactor technology, and in particular to a DC contactor. Background Technology

[0002] A DC contactor uses a push rod to move the moving contact against and separate from the stationary contact, thus achieving its switching function. In a DC contactor, the push rod is typically rotatable. If its rotational freedom is not constrained, the rotation of the push rod will cause the moving contact to deviate from the stationary contact, preventing them from making contact and resulting in the failure of the switching function. Therefore, a limiting structure must be designed in the DC contactor to restrict the rotation of the push rod.

[0003] Currently, the commonly used limiting structures in existing technologies are of two types: one uses ceramic ribs inside the ceramic cover to limit the movement of the contact support protrusion of the push rod; the other relies on the ceramic ribs directly limiting the movement of the moving contact. Both of these limiting structures suffer from problems such as difficulties in ceramic molding, excessive occupation of the internal space of the ceramic cover leading to limited arcing space, and limited short-circuit space. Therefore, it is necessary to improve the existing technologies to overcome their shortcomings. Utility Model Content

[0004] The problem to be solved by this utility model is to provide a DC contactor that overcomes the defects of existing DC contactor limiting structures, such as difficulties in ceramic molding, excessive occupation of the internal space of the ceramic cover resulting in limited arcing space, and limited short-circuit space.

[0005] The technical solution adopted by this utility model to solve its technical problem is: a DC contactor, comprising: a magnetic pole piece, a push rod assembly passing through the magnetic pole piece, and a movable contact piece mounted on the push rod assembly. The push rod assembly is used to push the movable contact piece to move in order to realize the on / off function of the DC contactor. The magnetic pole piece is provided with a first limiting feature, and the push rod assembly is provided with a second limiting feature. The first limiting feature and the second limiting feature are used in conjunction to restrict the rotational movement of the push rod assembly.

[0006] As a further improvement of this utility model, the first limiting feature is fixedly erected on the magnetic pole piece and located beside the second limiting feature. When the push rod assembly has a tendency to rotate in a clockwise or counterclockwise direction, the first limiting feature and the second limiting feature stop each other, thereby restricting the push rod assembly from rotating.

[0007] As a further improvement of this utility model, the height of the first limiting feature is satisfied that the second limiting feature can always form a limit with the first limiting feature within the movement stroke of the push rod assembly.

[0008] As a further improvement of this utility model, the push rod assembly includes an insulating base, and the second limiting feature is fixed to the insulating base.

[0009] As a further improvement of this utility model, the first limiting feature is fixed to the magnetic pole piece by welding, riveting or thread fastening; the second limiting feature is fixed to the insulating base by any one of the following methods: integral injection molding, insertion, riveting or using fasteners.

[0010] As a further improvement of this utility model, one of the first limiting feature and the second limiting feature includes at least one limiting member, and the other includes at least two limiting portions distributed on both sides of the limiting member.

[0011] As a further improvement of this utility model, the first limiting feature includes a limiting member, the magnetic pole piece is provided with a stepped hole with a small diameter at the top and a large diameter at the bottom, one end of the limiting member protrudes upward through the stepped hole and extends from the magnetic pole piece, and the other end of the limiting member is sealed and fixed in the stepped hole; the second limiting feature includes two integral or separate limiting parts, the two limiting parts protrude outward from the insulating base and are distributed side by side at intervals, and the limiting member is located between the two limiting parts.

[0012] As a further improvement of this utility model, the other end of the limiting member is provided with a solder pad, which is sealed and fixed in the stepped hole by brazing or laser welding.

[0013] Alternatively, the pad portion may be covered with a sealing cover, which is sealed and fixed within the stepped hole by brazing or laser welding.

[0014] As a further improvement of this utility model, the first limiting feature includes at least one limiting seat and at least two limiting parts fixedly disposed on the limiting seat. The limiting seat is provided with a first through hole, and the top of the magnetic pole piece is provided with a first protrusion. The first protrusion is inserted into the first through hole and riveted to fix it. The second limiting feature includes at least one limiting member, and the limiting member is located between the two limiting parts.

[0015] As a further improvement of this utility model, the DC contactor also includes an armature bracket, which is fixed to the top of the magnetic pole piece and mounted on the outside of the push rod assembly. The armature bracket is provided with a support leg, which serves as the first limiting feature. The second limiting feature includes a limiting member located next to the support leg, which cooperates with the support leg to form a rotational limiting.

[0016] The beneficial effects of this utility model are as follows: This utility model provides a DC contactor that uses a first limiting feature on the magnetic pole piece and a second limiting feature on the push rod assembly to constrain the rotational freedom of the push rod assembly, thereby ensuring the accurate relative position of the moving contact and the stationary contact, guaranteeing the switching function of the DC contactor. It eliminates the need for ceramic ribs inside the ceramic cover in existing technologies, avoiding the molding difficulties caused by ceramic ribs, reducing the difficulty of the production process, improving production efficiency, and helping to increase the product yield. Since it no longer relies on ceramic ribs for limiting, it can greatly reduce the space occupied inside the ceramic cover, allowing for more space inside the ceramic cover for arcing and short-circuit protection, improving the reliability of the DC contactor in terms of electrical performance, and reducing the risk of arcing and short-circuit faults. Furthermore, the limiting structure adopted in this utility model is not limited by the ceramic molding process, providing greater design flexibility and better adapting to DC contactors of different specifications and performance requirements. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a perspective view of the magnetic pole piece, push rod assembly, and moving contact piece in Embodiment 1 of the DC contactor of this utility model;

[0019] Figure 2 This is a cross-sectional view of the magnetic pole piece, push rod assembly, and moving contact piece in Embodiment 1 of the DC contactor of this utility model;

[0020] Figure 3 The DC contactor of this utility model Figure 2 Enlarged view of section A;

[0021] Figure 4 This is an exploded view of the push rod assembly and moving contact piece in Embodiment 1 of the DC contactor of this utility model;

[0022] Figure 5 This is a perspective view of the magnetic pole piece, push rod assembly, and moving contact piece in Embodiment 2 of the DC contactor of this utility model;

[0023] Figure 6 The DC contactor of this utility model Figure 5 Enlarged view of section B;

[0024] Figure 7 This is a perspective view of the magnetic pole piece, push rod assembly, and moving contact piece in Embodiment 3 of the DC contactor of this utility model;

[0025] Figure 8 The DC contactor of this utility model Figure 7 Enlarged view of section C;

[0026] Figure 9 This is a perspective view of the magnetic pole piece, push rod assembly, moving contact piece, and short-circuit protection structure in Embodiment 4 of the DC contactor of this utility model;

[0027] Figure 10 This is a top view of the two mounting methods of the insulating base and the limiting member in Embodiment 4 of the DC contactor of this utility model;

[0028] Figure 11 This is a perspective view of the magnetic pole piece, push rod assembly, and moving contact piece in Embodiment 5 of the DC contactor of this utility model;

[0029] Figure 12 This is a perspective view of the magnetic pole piece, push rod assembly, moving contact piece, and short-circuit protection structure in Embodiment Six of the DC contactor of this utility model;

[0030] Figure 13 This is a perspective view of the magnetic pole piece, push rod assembly, and moving contact piece in Embodiment 7 of the DC contactor of this utility model.

[0031] Referring to the accompanying drawings, the following explanations are provided:

[0032] 1. Magnetic pole piece; 101. Stepped hole; 102. First convex hull; 2. Moving contact piece;

[0033] 3. Insulating base; 301. Boss; 4. Limiting component; 401. Solder pad; 5. Limiting part; 6. Sealing cover; 7. Limiting seat; 701. First through hole; 8. Armature bracket; 801. Support leg; 9. Push rod; 10. Contact bracket; 11. Contact spring; 12. Solder sheet; 13. Lower armature; 14. Upper armature. Detailed Implementation

[0034] The present application will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0035] The following specific examples illustrate the implementation of this application. Those skilled in the art can easily understand other advantages and effects of this application from the content disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. This application can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this application. It should be noted that, in the absence of conflict, the following embodiments and features in the embodiments can be combined with each other. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0036] It should be noted that various aspects of embodiments within the scope of the appended claims are described below. It will be apparent that the aspects described herein can be embodied in a wide variety of forms, and any particular structure and / or function described herein is merely illustrative. Based on this application, those skilled in the art will understand that one aspect described herein can be implemented independently of any other aspect, and two or more of these aspects can be combined in various ways. For example, any number and aspects set forth herein can be used to implement the device and / or practice the method. Additionally, this device and / or method can be implemented using structures and / or functionalities other than one or more of the aspects set forth herein.

[0037] It should also be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of this application. The illustrations only show the components related to this application and are not drawn according to the number, shape and size of the components in actual implementation. In actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0038] Additionally, specific details are provided in the following description to facilitate a thorough understanding of the examples. However, those skilled in the art will understand that practice can be carried out without these specific details.

[0039] The technical solutions provided by the various embodiments of this application are described below with reference to the accompanying drawings.

[0040] Example 1

[0041] See Figures 1 to 4This utility model provides a DC contactor, including a magnetic pole piece 1, a push rod assembly, and a moving contact piece 2. The magnetic pole piece 1 has a central hole, and the push rod 9 of the push rod assembly passes through the central hole of the magnetic pole piece 1, with the other parts of the push rod assembly positioned above the magnetic pole piece 1. The moving contact piece 2 is mounted on the push rod assembly, which drives the moving contact piece 2 to move, causing it to contact and separate from the stationary contact of the DC contactor, thereby realizing the on / off function of the DC contactor.

[0042] In addition, in this embodiment, the DC contactor also includes an electromagnetic mechanism, a magnetic circuit section, and a housing (usually a ceramic housing). The electromagnetic mechanism, magnetic circuit section, and housing all employ existing conventional technologies and are not shown in the figures. The magnetic pole piece 1, as one component of the magnetic circuit section, is disposed between the electromagnetic mechanism and the housing. The housing is typically sealed and welded to the magnetic pole piece 1 via a connecting ring, covering the push rod assembly and the moving contact piece 2. The stationary contact is fixed to the housing. When the electromagnetic mechanism is energized, the magnetic field it generates causes the moving iron core in the magnetic circuit section to move upward and attract the stationary iron core. Simultaneously, the moving iron core pushes the moving contact piece 2 to contact the stationary contact via the push rod assembly, and the DC contactor is turned on. When the electromagnetic mechanism is de-energized, the magnetic field dissipates. Under the combined action of the contact spring 11 and the return spring between the moving and stationary iron cores, the moving iron core is driven downward and pushes the moving contact piece 2 to separate from the stationary contact via the push rod assembly, and the DC contactor is turned off.

[0043] As a key improvement of this application, the magnetic pole piece 1 is provided with a first limiting feature, and the push rod assembly is provided with a second limiting feature. The first and second limiting features work together to restrict the rotational movement of the push rod assembly. This invention constrains the rotational freedom of the push rod assembly by using the first limiting feature on the magnetic pole piece 1 in conjunction with the second limiting feature on the push rod assembly. This ensures the accurate relative position of the moving contact piece 2 and the stationary contact, guaranteeing the switching function of the DC contactor. It eliminates the need for ceramic ribs inside the ceramic cover, avoiding the molding difficulties caused by ceramic ribs, reducing manufacturing complexity, improving production efficiency, and increasing product yield. Since it no longer relies on ceramic ribs for limiting, it significantly reduces the space occupied inside the ceramic cover, providing more space for arcing and short-circuit protection. This improves the electrical reliability of the DC contactor and reduces the risk of arcing and short-circuit faults. Furthermore, the limiting structure used in this invention is not limited by the ceramic molding process, offering greater design flexibility and better adaptability to DC contactors with different specifications and performance requirements.

[0044] Furthermore, the first limiting feature is fixedly erected on the magnetic pole piece 1 and is located beside the second limiting feature. When the push rod assembly has a tendency to rotate in a clockwise or counterclockwise direction, the first limiting feature stops the second limiting feature, thereby restricting the push rod assembly from rotating.

[0045] It is worth noting that the height of the first limiting feature should satisfy the following condition: within the stroke of the push rod assembly, the second limiting feature can always form a limit with the first limiting feature, that is, within the stroke of the push rod assembly, the second limiting feature will not detach from the first limiting feature, and the first limiting feature can always stop the second limiting feature, ensuring the reliability of the rotational limiting of the push rod assembly.

[0046] like Figure 1 As shown, the push rod assembly includes an insulating base 3, and the second limiting feature is fixed to the insulating base 3.

[0047] In this embodiment, the second limiting feature includes two limiting parts 5, which can be integral or separate. For example... Figure 4 As shown, in this embodiment, the two limiting parts 5 are integrally formed, and the tail ends of the two limiting parts 5 are connected as a whole by a U-shaped part. In this embodiment, the insulating base 3 is made of plastic injection molding, and the two limiting parts 5 are fixed to the insulating base 3 by integral injection molding. The tail ends and U-shaped parts of the two limiting parts 5 are wrapped in plastic, while the front ends of the two limiting parts 5 protrude horizontally outward from the insulating base 3 and are distributed side by side at intervals.

[0048] See Figure 1 Two limiting parts 5 are arranged on one side of the wide side of the insulating base 3, and the length direction of the two limiting parts 5 is consistent with the length direction of the moving contact piece 2.

[0049] Of course, in other embodiments of this utility model, the two limiting parts 5 can also be fixed to the insulating base 3 by means of plugging, riveting or using fasteners.

[0050] Furthermore, the first limiting feature includes a limiting member 4, which can be fixed to the magnetic pole piece 1 by means of welding, riveting or thread fastening.

[0051] See Figure 2 and Figure 3 In this embodiment, the magnetic pole piece 1 is provided with a stepped hole 101 with a small upper diameter and a large lower diameter. One end of the limiting member 4 passes through the stepped hole 101 and protrudes upward from the magnetic pole piece 1, and is located between the two limiting parts 5; the other end of the limiting member 4 is sealed and fixed in the stepped hole 101.

[0052] When the push rod assembly tends to rotate clockwise, the right limit part 5 on the insulating base 3 stops on the limit member 4 to form a limit; similarly, when the push rod assembly tends to rotate counterclockwise, the left limit part 5 on the insulating base 3 stops on the limit member 4 to form a limit.

[0053] This invention achieves limiting by fixing the limiting part 5 in the insulating base 3 of the push rod assembly and the limiting part 4 on the magnetic pole piece 1. This structure is more stable than the prior art and can more effectively limit the rotation of the push rod assembly, ensuring that the moving contact piece 2 accurately contacts and separates from the stationary contact, ensuring the reliable realization of the DC contactor's switching function, and eliminating the problem of switching function failure caused by the deviation of the moving contact piece 2.

[0054] Continue reading Figure 2 and Figure 3 The other end of the limiting member 4 is provided with a solder pad 401, which is preferably circular, and a solder sheet 12 is placed between the solder pad 401 and the stepped surface in the stepped hole 101. The solder pad 401 is sealed and fixed in the stepped hole 101 by brazing to prevent air leakage at the connection position between the magnetic pole piece 1 and the limiting member 4, and to ensure the airtightness of the internal space of the DC contactor housing.

[0055] See Figure 4 The push rod assembly also includes a push rod 9, a contact bracket 10, and a contact spring 11. The bottom of the contact bracket 10 is also fixed to the insulating base 3 by integral injection molding and is insulated from the limiting part 5. When the DC contactor is turned on, the contact bracket 10 is at the high-voltage end, while the limiting part 5 is at the low-voltage end. The contact bracket 10 and the limiting part 5 must meet the requirements for withstand voltage and insulation distance.

[0056] Preferably, the present invention provides a boss 301 at one end of the insulating base 3, and the limiting part 5 is integrally injection molded into the boss 301, thereby meeting the pressure resistance and insulation distance requirements between the contact bracket 10 and the limiting part 5.

[0057] Furthermore, the contact support 10 is frame-shaped, with the moving contact 2 extending transversely through it. The two ends of the contact spring 11 elastically abut against the moving contact 2 and the insulating base 3, respectively. In some DC contactors with short-circuit protection, for example, a lower armature is provided at the bottom of the moving contact 2. In this case, the upper end of the contact spring 11 elastically abuts against the lower armature, and the elastic force applied to the lower armature causes the moving contact 2 to be stopped upwards at the top of the contact support 10.

[0058] In this embodiment, the limiting member 4 and the limiting part 5 can be made of materials such as ceramic or wear-resistant metal, and their shapes are not limited, such as round, square, etc.

[0059] It should be noted that the number of the first and second limiting features in this application is not limited. As long as they can form a rotational limiting effect on the push rod assembly, the number and position can be appropriately changed.

[0060] Example 2

[0061] See Figure 5 and Figure 6 The difference between this embodiment and the first embodiment is that the DC contactor also includes a sealing cover 6, which is installed inside the stepped hole 101.

[0062] In this embodiment, the sealing cover 6 is U-shaped and covers the solder pad portion 401. The sealing cover 6 can be sealed and fixed within the stepped hole 101 by laser welding. This invention, by setting the sealing cover 6, can achieve both sealing and fixing of the limiting member 4. Compared to the brazing method in Embodiment 1, the laser welding method using the sealing cover 6 greatly improves efficiency, facilitates automated welding, and enhances welding strength.

[0063] Of course, in other embodiments of this utility model, the sealing cover 6 may not be provided. By changing the size and shape of the solder pad portion 401, it can meet the requirements for laser welding, and thus the laser welding method can be directly adopted.

[0064] Example 3

[0065] The difference between this embodiment and Embodiment 1 is that the structures of the first limiting feature and the second limiting feature are different.

[0066] For details, please refer to Figure 7 and Figure 8 In this embodiment, the first limiting feature includes a limiting seat 7 and two limiting parts 5. The limiting seat 7 is fixed to the top of the magnetic pole piece 1, and the two limiting parts 5 are both fixedly disposed on the limiting seat 7 in a vertical direction, and the two limiting parts 5 are distributed side by side at intervals. The two limiting parts 5 can be integrally formed with the limiting seat 7, or they can be separately formed and then fixedly connected.

[0067] In this embodiment, the second limiting feature includes a limiting member 4, which is horizontally distributed and fixed to the insulating base 3 by integral injection molding. One end of the limiting member 4 protrudes outward from the insulating base 3 and extends between the two limiting portions 5. In other embodiments of this invention, the two limiting members 4 can also be fixed to the insulating base 3 by insertion, riveting, or the use of fasteners.

[0068] When the push rod assembly tends to rotate clockwise, the limiting member 4 on the insulating base 3 stops on the left limiting part 5 to form a limit; similarly, when the push rod assembly tends to rotate counterclockwise, the limiting member 4 on the insulating base 3 stops on the right limiting part 5 to form a limit.

[0069] See Figure 8 The limiting seat 7 has, but is not limited to, two first through holes 701. The top of the magnetic pole piece 1 has two first protrusions 102. The two first protrusions 102 are inserted into the two first through holes 701 one by one and riveted to fix them. Alternatively, the two first protrusions 102 can be inserted into the two first through holes 701 one by one for positioning, and then the limiting seat 7 can be fixed to the magnetic pole piece 1 by welding (such as laser welding).

[0070] Compared with Embodiment 1 or Embodiment 2, this embodiment uses a riveting method between the limiting seat 7 and the magnetic pole piece 1, which can avoid sealing problems caused by poor welding, and the assembly is also simpler.

[0071] Example 4

[0072] The difference between this embodiment and Embodiment 1 is that the structures of the first limiting feature and the second limiting feature are different. In addition, the DC contactor in this embodiment also includes a short-circuit protection structure.

[0073] See Figure 9 and Figure 10 The short-circuit protection structure includes an armature support 8, a lower armature 13, and an upper armature 14. The lower armature 13 is U-shaped and is fitted from bottom to top onto the bottom of the moving contact 2. The upper end of the contact spring 11 elastically abuts against the lower armature 13. The elastic force applied to the lower armature 13 causes the moving contact 2 to be stopped upward against the top of the contact support 10. The armature support 8 is fixed to the top of the magnetic pole piece 1 and mounted on the outside of the push rod assembly. The upper armature 14 is fixed to the lower surface of the top of the armature support 8 and is spaced apart from the lower armature 13. When the DC contactor is turned on, i.e., the moving contact 2 contacts the stationary contact, the current flowing through the moving contact 2 generates a magnetic field around it, magnetizing the lower armature 13 and the upper armature 14, causing an attraction between them. This attraction acts directly on the moving contact 2, thereby increasing the contact pressure and improving the short-circuit current withstand capability.

[0074] See Figure 9 The armature bracket 8 is provided with, but not limited to, four support legs 801 distributed in the vertical direction. The bottom of each support leg 801 is provided with a folded edge, and the folded edge is provided with a second through hole. The second through hole is used to rivet with the second protrusion provided on the top of the magnetic pole piece 1 to fix the armature bracket 8.

[0075] In this embodiment, the support leg 801 serves as the first limiting feature, and the second limiting feature includes a limiting member 4. The limiting member 4 is distributed in a horizontal direction and is fixed to the insulating base 3 by an integral injection molding method. At the same time, one end of the limiting member 4 protrudes outward from the insulating base 3 and is located beside the support leg 801. The limiting member 4 and the support leg 801 cooperate to form a rotational limiting.

[0076] It is understandable that at least two limiting members 4 should be provided; the two limiting members 4 can be integrally connected or separate; for example Figure 10 As shown, the two limiting members 4 can be set on the same side of the insulating base 3 or on both sides of the insulating base 3.

[0077] The two limiting members 4 are used in conjunction with the corresponding two support legs 801. When the push rod assembly has a tendency to rotate clockwise, one of the limiting members 4 on the insulating base 3 stops on the support leg 801 next to it, thereby forming a limit. Similarly, when the push rod assembly has a tendency to rotate counterclockwise, the other limiting member 4 on the insulating base 3 stops on the support leg 801 next to it, thereby forming a limit.

[0078] Since this embodiment relies on the armature bracket 8 to fix the upper armature 14, and can also use the support leg 801 to directly serve as the first limiting feature, the structure is simpler than that of embodiments one to three.

[0079] Example 5

[0080] See Figure 11 The difference between this embodiment and Embodiment 1 or Embodiment 2 is that the two limiting parts 5 are arranged on one side of the long side of the insulating base 3. A boss 301 is provided in the middle of the side of the long side of the insulating base 3. The tail ends and U-shaped parts of the two limiting parts 5 are wrapped in the boss 301. At the same time, the front ends of the two limiting parts 5 protrude horizontally outward from the boss 301 and are distributed side by side at intervals. That is, the length direction of the two limiting parts 5 is perpendicular to the length direction of the moving contact piece 2.

[0081] Example 6

[0082] See Figure 12 The difference between this embodiment and embodiment four is that: two limiting members 4 are arranged on both sides of the insulating base 3 and are diagonally distributed, with one limiting member 4 located inside the support leg 801 next to it and the other limiting member 4 located outside the support leg 801 next to it.

[0083] The two limiting members 4 are used in conjunction with the corresponding two supporting legs 801. When the push rod assembly has a tendency to rotate clockwise, the limiting member 4 located inside the supporting leg 801 stops on the supporting leg 801 to form a limit. Similarly, when the push rod assembly has a tendency to rotate counterclockwise, the limiting member 4 located outside the supporting leg 801 stops on the supporting leg 801 to form a limit.

[0084] Example 7

[0085] See Figure 13 The difference between this embodiment and embodiment three is that the first limiting feature includes two limiting seats 7 and two limiting parts 5.

[0086] Specifically, the two limiting parts 5 are respectively fixedly disposed on the two limiting seats 7. As a preferred embodiment, the limiting parts 5 and the limiting seats 7 connected thereto are integrally formed and are L-shaped as a whole.

[0087] Both limiting seats 7 are fixed to the top of the magnetic pole piece 1, and both limiting parts 5 are fixed vertically on the limiting seats 7, with the two limiting parts 5 spaced apart. One end of the limiting member 4 protrudes outward from the insulating base 3 and extends between the two limiting parts 5. When the push rod assembly tends to rotate clockwise, the limiting member 4 on the insulating base 3 stops on the left limiting part 5, thus forming a limit; similarly, when the push rod assembly tends to rotate counterclockwise, the limiting member 4 on the insulating base 3 stops on the right limiting part 5, thus forming a limit.

[0088] Each of the two limiting seats 7 has at least one first through hole 701, and the top of the magnetic pole piece 1 has at least two first protrusions 102. The first protrusions 102 are inserted into the first through holes 701 and riveted to fix them. Alternatively, the first protrusions 102 can be inserted into the first through holes 701 for positioning first, and then the limiting seat 7 can be fixed to the magnetic pole piece 1 by welding (such as laser welding).

[0089] Therefore, this utility model of DC contactor uses the first limiting feature on the magnetic pole piece 1 and the second limiting feature on the push rod assembly to constrain the rotational freedom of the push rod assembly, thereby ensuring the accurate relative position of the moving contact piece 2 and the stationary contact, guaranteeing the switching function of the DC contactor. It eliminates the need for ceramic ribs inside the ceramic cover, avoiding the molding difficulties caused by ceramic ribs, reducing production difficulty, improving production efficiency, and increasing product yield. Since it no longer relies on ceramic ribs for limiting, it significantly reduces the space occupied inside the ceramic cover, providing more space for arcing and short-circuit protection, improving the electrical reliability of the DC contactor, and reducing the risk of arcing and short-circuit faults. Furthermore, the limiting structure used in this utility model is not limited by the ceramic molding process, offering greater design flexibility and better adaptability to DC contactors of different specifications and performance requirements.

[0090] The same or similar parts between the various embodiments in this specification can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments.

[0091] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A DC contactor, comprising a magnetic pole piece (1), a push rod assembly passing through the magnetic pole piece (1), and a movable contact piece (2) mounted on the push rod assembly, wherein the push rod assembly is used to push the movable contact piece (2) to move to realize the switching function of the DC contactor; characterized in that: The magnetic pole piece (1) is provided with a first limiting feature, and the push rod assembly is provided with a second limiting feature. The first limiting feature and the second limiting feature are used together to restrict the push rod assembly from rotating.

2. The DC contactor according to claim 1, characterized in that: The first limiting feature is fixedly erected on the magnetic pole piece (1) and located beside the second limiting feature. When the push rod assembly has a tendency to rotate in a clockwise or counterclockwise direction, the first limiting feature and the second limiting feature stop each other, thereby restricting the push rod assembly from rotating.

3. The DC contactor according to claim 2, characterized in that: The height of the first limiting feature satisfies the condition that the second limiting feature can always form a limit with the first limiting feature within the stroke of the push rod assembly.

4. The DC contactor according to claim 2, characterized in that: The push rod assembly includes an insulating base (3), and the second limiting feature is fixed to the insulating base (3).

5. The DC contactor according to claim 4, characterized in that: The first limiting feature is fixed to the magnetic pole piece (1) by welding, riveting or thread fastening; the second limiting feature is fixed to the insulating base (3) by any one of the following methods: integral injection molding, plugging, riveting or using fasteners.

6. The DC contactor according to claim 4, characterized in that: One of the first limiting feature and the second limiting feature includes at least one limiting member (4), and the other includes at least two limiting portions (5) distributed on both sides of the limiting member (4).

7. The DC contactor according to claim 6, characterized in that: The first limiting feature includes a limiting member (4), the magnetic pole piece (1) is provided with a stepped hole (101) with a small diameter at the top and a large diameter at the bottom, one end of the limiting member (4) passes through the stepped hole (101) and protrudes upward from the magnetic pole piece (1), and the other end of the limiting member (4) is sealed and fixed in the stepped hole (101); the second limiting feature includes two integral or separate limiting parts (5), the two limiting parts (5) protrude outward from the insulating base (3) and are distributed side by side at intervals, and the limiting member (4) is located between the two limiting parts (5).

8. The DC contactor according to claim 7, characterized in that: The other end of the limiting member (4) is provided with a solder pad (401), which is sealed and fixed in the stepped hole (101) by brazing or laser welding. Alternatively, a sealing cover (6) may be provided on the pad portion (401), and the sealing cover (6) may be sealed and fixed in the stepped hole (101) by brazing or laser welding.

9. The DC contactor according to claim 6, characterized in that: The first limiting feature includes at least one limiting seat (7) and at least two limiting parts (5) fixedly disposed on the limiting seat (7). The limiting seat (7) is provided with a first through hole (701). The top of the magnetic pole piece (1) is provided with a first protrusion (102). The first protrusion (102) is inserted into the first through hole (701) and riveted to fix it. The second limiting feature includes at least one limiting member (4). The limiting member (4) is located between the two limiting parts (5).

10. The DC contactor according to claim 4, characterized in that: It also includes an armature bracket (8), which is fixed to the top of the magnetic pole piece (1) and mounted on the outside of the push rod assembly. The armature bracket (8) is provided with a support leg (801), which serves as the first limiting feature. The second limiting feature includes a limiting member (4) located next to the supporting leg (801). The limiting member (4) cooperates with the supporting leg (801) to form a rotational limiting.

Images