Moving contact of direct current circuit breaker and contact system

Abstract

The utility model provides a moving contact and a contact system of a direct current circuit breaker, the moving contact comprises two pieces which are respectively marked as a left moving contact and a right moving contact, the left moving contact and the right moving contact are symmetrically arranged, a gap exists between the left moving contact and the right moving contact, the left moving contact is provided with a left silver contact, and the right moving contact is provided with a right silver contact. A left silver contact is arranged on the left moving contact, a left arc contact is further detachably installed on the left moving contact above the left silver contact, a right silver contact is arranged on the right moving contact, a right arc contact is further detachably installed on the right moving contact above the right silver contact, an elastic piece is arranged between the left moving contact and the right moving contact, and through kidney-shaped holes are further formed in the left moving contact and the right moving contact. And the kidney-shaped hole is formed above the elastic piece. According to the utility model, the arcing contact is contacted before the silver contact in the closing process, and the silver contact is disconnected before the arcing contact in the opening process, so that the service life of the moving contact can be effectively prolonged, the moving contact has the characteristics of large current capacity and long service life, and the safety and reliability of the circuit breaker in the using process are improved.

Description

Technical Field

[0001] The utility model relates to the technical field of circuit breakers, in particular to a moving contact and a contact system of a DC circuit breaker. Background Art

[0002] DC circuit breakers are key equipment for the safe operation and protection of rail transit traction power supply networks. They can close, carry and break currents under normal circuit conditions, and can also close and carry certain abnormal currents and short-circuit breaking currents under specified abnormal circuit conditions. With the large-scale development of urban rail transit, the demand for the working current capacity of DC circuit breakers is increasing, and the service life is also required to be increased accordingly.

[0003] Most of the current DC circuit breakers are single-contact structures with large contact resistance and severe temperature rise. In addition, most arc contacts have the disadvantages of complex structure and low reliability.

[0004] For example, the authorization announcement number CN217933688U discloses an arc-striking angle and contact structure of a DC circuit breaker, which includes a static arc-striking angle structure, a dynamic arc-striking angle structure, a busbar, a static contact piece, a dynamic contact piece and a dynamic contact seat; the static arc-striking angle structure, the busbar and the static contact piece are welded and fixed together, and the static arc-striking angle structure is located at a corresponding position above the busbar; the dynamic contact piece and the dynamic contact seat are welded and fixed together, and the dynamic arc-striking angle structure is installed at a corresponding position above the dynamic contact seat. The arc-striking angle and contact structure of the DC circuit breaker provided by the utility model reduces the risk of arc reignition without the need for a magnetic blowing device. However, the arc contact of the arc-striking angle and contact structure has the disadvantages of complex structure and low reliability.

[0005] The DC circuit breaker high current moving contact system disclosed in the application announcement number CN115132547A includes: a moving contact, a closing latch and a moving contact support; the number of the moving contacts is 2; the moving contact support includes: a tail, a middle and a head; the head of the moving contact support is embedded between the two moving contacts and is rotatably connected to the two moving contacts respectively. The moving contact system solves the problem that the moving contact of the existing DC circuit breaker is a single contact structure, has a large contact resistance and a serious temperature rise. However, the moving contact system lacks an arc contact and has the disadvantage of a short service life. Summary of the invention

[0006] Purpose of the invention: In order to overcome the deficiencies of the above-mentioned prior art, the present application provides a moving contact and a contact system of a DC circuit breaker, which solves the problems of complex structure, low reliability and short life during the use of the circuit breaker.

[0007] Technical solution: The utility model provides a moving contact of a DC circuit breaker, the moving contact comprising two pieces, respectively referred to as a left moving contact and a right moving contact, the left moving contact and the right moving contact are symmetrically arranged with a gap therebetween, the left moving contact is provided with a left silver contact, a left arc contact is detachably mounted on the left moving contact above the left silver contact, the right moving contact is provided with a right silver contact, a right arc contact is detachably mounted on the right moving contact above the right silver contact, an elastic member is provided between the left moving contact and the right moving contact, through waist holes are also provided on the left moving contact and the right moving contact, the waist holes are arranged above the elastic member.

[0008] Further, including:

[0009] Through holes are respectively provided at corresponding positions of the left moving contact and the right moving contact, and connecting shafts passing through the left moving contact and the right moving contact are provided in the two through holes, and symmetrical fixing parts are provided at both ends of the connecting shafts, and the cross-section of the fixing parts is set to be circular, and its diameter is larger than the diameter of the through holes.

[0010] Further, including:

[0011] First blind holes are provided on the corresponding surfaces of the left moving contact and the right moving contact, and a first limiting rod is installed between the two first blind holes.

[0012] Further, including:

[0013] Second blind holes are provided on the corresponding surfaces of the left moving contact and the right moving contact below the first blind hole, and a second limiting rod is provided between the two second blind holes.

[0014] Further, including:

[0015] In the height direction of the moving contact, the connecting shaft is arranged between the first limiting rod and the second limiting rod.

[0016] Further, including:

[0017] The gap between the left moving contact and the right moving contact is 1-2 mm.

[0018] On the other hand, the present invention also provides a contact system for a DC circuit breaker, which includes the above-mentioned moving contact, static contact and moving-side arc-striking row, wherein the moving-side arc-striking row is fixed above the moving contact, and one side surface of the moving contact on which the left silver contact and the right silver contact are arranged is recorded as surface A, and the other side surface of the moving contact opposite to the surface A is recorded as surface B, a static contact is arranged in front of the surface A, a limit block is arranged below the moving-side arc-striking row, and after the moving contact rotates counterclockwise to the maximum angle, the limit block is used to stop the rotation of the moving contact.

[0019] Further, including:

[0020] It also includes a push rod and a trip spring, wherein the push rod is connected to the surface B, the trip spring is installed on the surface A, and the trip spring is arranged above the waist hole.

[0021] Further, including:

[0022] A limiting shaft is arranged in the waist hole, and the limiting shaft moves left and right in the length direction of the waist hole, thereby making the moving contact rotate clockwise or counterclockwise around the center of the limiting shaft.

[0023] Beneficial effects: Compared with the prior art, the utility model has the following advantages:

[0024] The utility model provides a double contact system of a DC circuit breaker, which adopts double moving contacts that are symmetrical on the left and right, and is equipped with fixedly installed left and right arc contacts. A waist hole is opened at the bottom of the moving contact, so that in the closing process, the arc contact contacts before the silver contact, and in the opening process, the silver contact disconnects before the arc contact, which can effectively improve the service life of the moving contact, has the characteristics of large current capacity and long service life, and improves the safety and reliability of the circuit breaker during use. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the embodiments of the present application 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 present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0026] Figure 1 It is a schematic diagram of the structure of the moving contact of the utility model;

[0027] Figure 2 It is a side view of the moving contact of the utility model;

[0028] Figure 3 This is the front view of the utility model;

[0029] Figure 4 It is a structural schematic diagram of the initial state of the contact system of the utility model;

[0030] Figure 5 It is a schematic diagram of the closed state of the contact system of the utility model;

[0031] Figure 6 This is a schematic diagram of the contact system of the utility model in the open state;

[0032] The figure includes: left moving contact 1, left silver contact 2, left arc contact 3, right moving contact 4, right silver contact 5, right arc contact 6, first limit rod 8, connecting shaft 9, through hole 92, fixing part 91, waist hole 11, screw 12, moving side arc striking row 13, limit block 14, static contact 15, opening spring 16, limit shaft 17, push rod 18, first blind hole 41, second blind hole 42, surface A101, surface B201. DETAILED DESCRIPTION

[0033] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present application.

[0034] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequential order. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present application described here. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0035] In the present application, the terms "upper", "lower", "left", "right", "front", "back", "top", "bottom", "inner", "outer", "middle", "vertical", "horizontal", "lateral", "longitudinal" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings. These terms are mainly used to better describe the present application and its embodiments, and are not used to limit the indicated devices, elements or components to have a specific orientation, or to be constructed and operated in a specific orientation.

[0036] In addition, some of the above terms may be used to express other meanings in addition to indicating orientation or positional relationship. For example, the term "on" may also be used to express a certain dependency or connection relationship in some cases. For those of ordinary skill in the art, the specific meanings of these terms in this application can be understood according to specific circumstances.

[0037] In addition, the terms "installed", "set", "provided with", "connected", "connected", and "socketed" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection, or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be an internal connection between two devices, elements, or components. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0038] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0039] Example 1

[0040] In one aspect of the present invention, Figure 1 As shown, a moving contact of a DC circuit breaker is provided, the number of moving contacts is 2, the left moving contact 1 and the right moving contact 4 are symmetrical, and there is a gap between the left moving contact 1 and the right moving contact 4. In this embodiment, the gap distance is set to 1-2 mm.

[0041] like Figure 2 and 3 As shown, the left silver contact 2 is welded on the left moving contact 1. Above the left silver contact 2 is a detachable left arc contact 3. The left arc contact 3 can be fixed to the left moving contact 1 by a fixing screw 12. The right silver contact 5 is welded on the right moving contact 4. Above the right silver contact 5 is a detachable right arc contact 6. The right arc contact 6 can be fixed to the right moving contact 4 by a fixing screw 12. The left arc contact and the right arc contact can be removed from the moving contact for maintenance and replacement, and are made of copper-tungsten alloy.

[0042] Blind holes are opened on the left moving contact 1 and the right moving contact 4, and the corresponding blind holes can be inserted with the first limiting rod 8 and the second limiting rod 10 to prevent the left moving contact 1 from fitting with the right moving contact 4 and ensure that there is a gap between the left moving contact 1 and the right moving contact 4.

[0043] Specifically: through holes 92 are respectively opened at corresponding positions of the left moving contact 1 and the right moving contact 4, and connecting shafts 9 passing through the left moving contact and the right moving contact are arranged in the two through holes, and symmetrical fixing parts 91 are arranged at both ends of the connecting shaft 9, and the cross-section of the fixing part 91 is set to be circular, and the diameter of the fixing part 91 is larger than the diameter of the through hole 92, and the connecting shaft 9 is used to connect the left moving contact 1 and the right moving contact 4.

[0044] A first blind hole 41 is provided on the corresponding surface of the left moving contact 1 and the right moving contact 4, and a first limiting rod 8 is installed between the two first blind holes 41. A second blind hole 42 is provided on the corresponding surface of the left moving contact 1 and the right moving contact 4 below the first blind hole 41, and a second limiting rod 10 is provided between the two second blind holes 42. In this embodiment, in the height direction of the moving contact, the connecting shaft 9 is provided between the first limiting rod 8 and the second limiting rod 10.

[0045] Furthermore, in this embodiment, there is an elastic member 7 between the left moving contact 1 and the right moving contact 4. Specifically, in this embodiment, it is a compression spring, which provides elastic force between the left moving contact 1 and the right moving contact 4. A through waist hole 11 is also opened on the left moving contact 1 and the right moving contact 4. The waist hole 11 is arranged above the elastic member 7.

[0046] Example 2

[0047] On the other hand, the utility model also provides a double contact system of a DC circuit breaker, which includes the above-mentioned double moving contacts, and a matching arc-striking row and other structures, the moving side arc-striking row 13 is fixed above the moving contact, and one side of the moving contact on which the left silver contact 2 and the right silver contact 3 are arranged is recorded as surface A101, and the other side of the moving contact opposite to the surface A101 is recorded as surface B201, and a static contact is arranged in front of the surface A101, and a limit block 14 is arranged below the moving side arc-striking row 13, and after the moving contact rotates counterclockwise to the maximum angle, the limit block 14 is used to block the rotation of the moving contact. In this embodiment, the distance relationship between the moving side arc-striking row, the static contact, the limit block and the moving contact is not specifically limited, and is set according to actual needs, and the length of the waist hole 11 is also set according to the specific stroke, but the overall position and direction are as described above.

[0048] The opening and closing process of this contact system is introduced below:

[0049] 1. Initial State

[0050] like Figure 4 As shown, the moving contact is in the opening position, and the moving contact can rotate around the limit shaft 17 to realize the closing and opening operations of the static contact 15. When the moving contact rotates counterclockwise, the limit block 14 blocks the rotation of the moving contact to keep it in the opening position. Since the opening spring 16 is located above the limit shaft 17, it will push the moving contact to move toward the opening position, so that the limit shaft 17 is located to the right of the waist hole 11.

[0051] 2. Closing process

[0052] like Figure 5As shown in the figure, when the closing push rod 18 pushes the moving contact to close, the opening spring 16 is located above the limit shaft 17, and the moving contact will rotate around the limit shaft 17 as the center. After reaching the vertical position, the moving contact will continue to rotate clockwise around the limit shaft 17 as the center to an inclined angle, at which time the left arc contact 3 and the right arc contact 6 first contact with the static contact 15. Figure 6 As shown, when the closing push rod 18 continues to push the moving contact, since the left arc contact 3 and the right arc contact 6 have already contacted the static contact 15, the moving contact will rotate counterclockwise around the contact point as the center of the circle, so that the left silver contact 2, the right silver contact 5 and the static contact 15 contact, completing the closing process of the contact. At this time, the limit shaft 17 is located on the left side of the waist hole 11.

[0053] 3. Opening process

[0054] like Figure 6 As shown, in the closed position, the left silver contact 2, the right silver contact 5 and the static contact 15 are in contact, and the limit shaft 17 is located to the left of the waist hole 11. Figure 5 As shown in the figure, when the closing push rod 18 moves backward and the moving contact begins to open, since the opening spring 16 is located above the limit shaft 17, the moving contact will rotate clockwise around the contact point of the left arc contact 3, the right arc contact 6 and the static contact 15 as the center of the circle. At this time, the left silver contact 2, the right silver contact 5 and the static contact 15 are out of contact, and the limit shaft 17 is located to the right of the waist hole 11. Figure 4 As shown, the closing push rod 18 continues to move backward. Since the limit shaft 17 is already located to the right of the waist hole 11, the moving contact will rotate counterclockwise around the limit shaft 17 as the center of the circle, and the left arc contact 3, the right arc contact 6 and the static contact 15 will be out of contact. The moving contact will continue to rotate counterclockwise around the limit shaft 17 as the center of the circle until the limit block 14 blocks the rotation of the moving contact, so that it remains in the opening position, completing the opening of the moving contact.

[0055] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A moving contact of a DC circuit breaker, characterized in that: The moving contact includes two pieces, which are respectively marked as a left moving contact and a right moving contact. The left moving contact and the right moving contact are symmetrically arranged with a gap therebetween. A left silver contact is arranged on the left moving contact, and a left arc contact is detachably mounted on the left moving contact above the left silver contact. A right silver contact is arranged on the right moving contact, and a right arc contact is detachably mounted on the right moving contact above the right silver contact. An elastic member is arranged between the left moving contact and the right moving contact, and through waist holes are also opened on the left moving contact and the right moving contact, and the waist holes are arranged above the elastic member.

2. The moving contact of the DC circuit breaker according to claim 1, characterized in that: Through holes are respectively provided at corresponding positions of the left moving contact and the right moving contact, and connecting shafts passing through the left moving contact and the right moving contact are provided in the two through holes.

3. The moving contact of the DC circuit breaker according to claim 2, characterized in that: First blind holes are provided on the corresponding surfaces of the left moving contact and the right moving contact, and a first limiting rod is installed between the two first blind holes.

4. The moving contact of the DC circuit breaker according to claim 3, characterized in that: Second blind holes are provided on the corresponding surfaces of the left moving contact and the right moving contact below the first blind hole, and a second limiting rod is provided between the two second blind holes.

5. The moving contact of the DC circuit breaker according to claim 4, characterized in that: In the height direction of the moving contact, the connecting shaft is arranged between the first limiting rod and the second limiting rod.

6. The moving contact of the DC circuit breaker according to claim 1, characterized in that: The gap between the left moving contact and the right moving contact is 1-2 mm.

7. A contact system for a DC circuit breaker, characterized in that: It includes the moving contact, static contact and moving-side arc-striking row as described in any one of claims 1 to 6, the moving-side arc-striking row is fixed above the moving contact, one side of the moving contact on which the left silver contact and the right silver contact are arranged is recorded as surface A, the other side of the moving contact opposite to the surface A is recorded as surface B, a static contact is arranged in front of the surface A, a limiting block is arranged below the moving-side arc-striking row, and after the moving contact rotates counterclockwise to the maximum angle, the limiting block is used to stop the rotation of the moving contact.

8. The contact system of the DC circuit breaker according to claim 7, characterized in that: It also includes a push rod and a trip spring, wherein the push rod is connected to the surface B, the trip spring is installed on the surface A, and the trip spring is arranged above the waist hole.

9. The contact system of the DC circuit breaker according to claim 8, characterized in that: A limiting shaft is arranged in the waist hole, and the limiting shaft moves left and right in the length direction of the waist hole, thereby making the moving contact rotate clockwise or counterclockwise around the center of the limiting shaft.

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