Contact clamping structure of circuit breaker and circuit breaker

Abstract

The utility model discloses a contact clamping structure of a circuit breaker and the circuit breaker using the same, and the contact clamping structure comprises a static contact, a strip-shaped moving contact, an elastic clamping piece, a clamping piece, a clamping fixing shaft, and a moving contact fixing shaft. The moving contacts with parallel plate surfaces form a moving contact group through a moving contact fixing shaft through which the far clamping ends penetrate, the number of the static contacts is the same as the number of the gaps between the moving contacts, and the extending parts of the static contacts extend into the gaps between the moving contacts and are clamped by the elastic clamping piece and the clamping piece during closing; through the structure, the problem of low short-term tolerance in the prior art is solved, and the technical effect of effectively improving the short-term tolerance is achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of low-voltage electrical appliances, in particular to a contact clamping structure of a circuit breaker and a circuit breaker. Background Art

[0002] The current state-of-the-art closing method for DC molded case circuit breakers is a snap-on method. Upon closing, the moving contact strikes the static contact, causing them to snap together. When a high current flows, the contacts immediately open, resulting in a short withstand time and low short-circuit withstand performance. Clamping structures are also available for contact closing, but these structures have too little overlap between the moving and static contacts, effectively failing to improve short-circuit withstand performance. Furthermore, increasing the overlap would make it difficult to secure the moving contact. Summary of the Invention

[0003] In view of the deficiencies of the prior art, the present invention provides a contact clamping structure of a circuit breaker and a circuit breaker, so as to solve the problem of insufficient short-time withstand performance of the prior art.

[0004] In order to achieve the above objectives, the present invention is implemented through the following technical solutions:

[0005] A contact clamping structure for a circuit breaker, comprising a static contact and a strip-shaped moving contact, and further comprising an elastic clamping member, a clamping member, a clamping fixing shaft, and a moving contact fixing shaft. The moving contact comprises a static contact clamping end and a distal clamping end, and the number of movable contacts parallel to the plate surfaces of more than two pieces is formed into a movable contact group through the movable contact fixing shaft through which the distal clamping end passes, and the gap between the plates is greater than one. The static contact comprises an insertion portion and a mounting portion. The number of the static contacts is the same as the number of gaps between the moving contact plates. The thickness of the insertion portion of the static contact is greater than the gap distance between the plates when the switch is opened, and the insertion end of the insertion portion is provided with chamfered edges or chamfers on both sides of the gap between the plates. Angle arc, when closing, the protruding part of the static contact extends into the gap between the plates of the moving contact, the fixed axis of the moving contact is perpendicular to the plate surface of the moving contact, and a clamping piece is installed on the outer side of the clamping end of the two outermost moving contacts and the static contact of the moving contact group, and the clamping end of the moving contact and the static contact is provided with an isolation platform on the inner side of the gap between the plates, and the height of the isolation platform in the gap between the plates is smaller than the gap between the plates when opening, and elastic clamping pieces are installed on the outer side of the two clamping pieces, and the elastic clamping piece clamps the protruding part of the static contact that extends into the gap between the moving contact plates when closing through the clamping piece through the clamping fixing axis passing through the moving contact, the clamping piece and the elastic clamping piece, and the clamping fixing axis is perpendicular to the plate surface of the moving contact.

[0006] Preferably, the elastic clamping member is a leaf spring, and the leaf spring is installed inwardly on the outside of the clamping member with its leaf arc facing inward.

[0007] Preferably, the leaf spring arc top is provided with a through hole for fixing and clamping the fixed shaft.

[0008] Preferably, the through hole is a gourd hole, and necks are provided at both ends of the clamping and fixing shaft, and the necks are clamped into the small end of the gourd hole.

[0009] Preferably, a leaf spring fixing boss is provided outwardly at one end of the clamping member, and a notch is provided at one end edge of the leaf spring corresponding to the leaf spring fixing boss of the clamping member to match the shape of the corresponding surface of the leaf spring fixing boss.

[0010] Preferably, both sides of the clamping piece are provided with bent wings facing the moving contact, and both side edges of the moving contact are provided with notches corresponding to the shape of the bent wings.

[0011] Preferably, an arc striking angle is provided upwardly at the end of the moving contact facing the static contact.

[0012] Preferably, the mounting portion of each static contact is perpendicular to the extending portion and the mounting portions of each static contact are stacked together.

[0013] Preferably, the movable contacts consist of four pieces, with the two middle pieces stacked together.

[0014] Based on the same inventive concept, the present application also discloses a circuit breaker, comprising a base, an actuator, a rotating shaft, an upper cover, and also the aforementioned contact clamping structure, soft connection and terminal block of the circuit breaker. The upper cover is directly or indirectly mounted on the base, the actuator is mounted in the upper cover, the rotating shaft is mounted in the base below the actuator, and a plurality of mounting slots for mounting the contact clamping structure of the circuit breaker are provided in the base. The terminal block is mounted at one end of the mounting slot, and the mounting portion of the static contact of the contact clamping structure of the circuit breaker is mounted at the other end of the mounting slot. Each of the moving contacts is electrically connected to the terminal block in its respective mounting slot through a soft connection. The mounting direction of the contact clamping structure of the circuit breaker is perpendicular to the overall direction of the rotating shaft and is mounted in the mounting cavity corresponding to the rotating shaft through the moving contact fixing shaft.

[0015] The contact clamping structure and circuit breaker of the circuit breaker proposed in this application adopt a clamping scheme design. After closing, the moving contact and the static contact are in a left-right contact state, and pressure is provided by the leaf springs on both sides of the moving contact, which significantly improves the short-time withstand performance of the circuit breaker. Using the contact clamping structure and circuit breaker of the circuit breaker of this application, the short-time withstand current can reach DC 120kA, with a performance index of 0.1s. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a three-dimensional schematic diagram of the periphery of the moving contact of an embodiment of a contact clamping structure for a circuit breaker;

[0017] Figure 2 A three-dimensional schematic diagram of a static contact of an embodiment of a contact clamping structure for a circuit breaker;

[0018] Figure 3A side view schematic diagram of an embodiment of a contact clamping structure of a circuit breaker installed on a rotating shaft in a closed state;

[0019] Figure 4 It is a front perspective schematic diagram of a contact clamping structure of a circuit breaker in a closed state according to an embodiment of the present invention;

[0020] Figure 5 This is a front perspective schematic diagram of a circuit breaker embodiment with the upper cover and the middle cover hidden;

[0021] Figure 6 It is a front perspective schematic diagram of an embodiment of a circuit breaker;

[0022] Figure 7 A side and rear perspective diagram of a circuit breaker embodiment with the upper cover and the middle cover hidden;

[0023] Figure 8 It is a side and rear perspective diagram of a circuit breaker embodiment with the upper cover hidden;

[0024] Figure 9 This is an equivalent circuit diagram of an embodiment of a contact clamping structure of a circuit breaker after closing;

[0025] Among them, 1-contact clamping structure, 11-moving contact, 111-isolating platform, 112-arcing angle, 12-static contact, 121-extending part, 122-installing part, 13-leaf spring, 14-clamping part, 141-leaf spring fixing boss, 142-bending wing, 15-clamping fixing shaft, 16-moving contact fixing shaft, 17-soft connection, 2-terminal block, 3-rotating shaft, 31-rotating shaft rotating shaft, 4-base, 5-actuator, 6-traction rod, 7-middle cover, 8-upper cover. DETAILED DESCRIPTION

[0026] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0027] This embodiment provides a technical solution: the contact clamping structure of the circuit breaker of the present application includes a static contact 12 and a strip-shaped moving contact 11, an elastic clamping member, a clamping member 14, a clamping fixing shaft 15, and a moving contact fixing shaft 16. The moving contact 11 includes a static contact clamping end and a distal clamping end. The four parallel plates of the moving contacts 11 are connected to the moving contact fixing shaft 16 through the distal clamping end to form a moving contact group. The two middle plates are stacked back to back so that there are two gaps between the plates. The static contact 12 includes an insertion portion 121 and a mounting portion 122. The number of the static contacts 12 is the same as the number of gaps between the plates of the moving contacts 11, which is also two. The thickness of the insertion portion 121 of the static contact 12 is greater than the distance between the gaps when the switch is open, and the insertion end of the insertion portion 121 is provided with chamfered edges or chamfered arcs on both sides of the gap between the plates. When the switch is closed, the insertion of the static contact 12 The movable contact 11 is fixed on the outer side of the movable contact 11, and the movable contact fixing shaft 16 is perpendicular to the plate surface of the movable contact 11. The static contact clamping end of the two outermost movable contacts 11 of the movable contact group is installed with a clamping piece 14 on the outer side. The static contact clamping end of the movable contact 11 is provided with an isolation platform on the inner side of the gap between the plates. The height of the isolation platform in the gap between the plates is less than the gap between the plates when the switch is opened. In this embodiment, for the convenience of manufacturing, a circular isolation platform is provided on one side of each movable contact, and it can also be provided as needed, for example, one piece has one and the other has no one. Elastic clamping pieces are installed on the outer side of the two clamping pieces 14, and the elastic clamping piece clamps the static contact 12 extending into the gap between the plates of the movable contact 11 when the switch is closed through the clamping piece 14 through the clamping piece 14. The clamping and fixing shaft 15 is perpendicular to the plate surface of the movable contact 11. In order to facilitate the installation of the entire structure into the circuit breaker, the mounting portion 122 of each static contact 12 is perpendicular to the extending portion 121 and the mounting portions 122 of each static contact 12 are stacked together. In this embodiment, the mounting portions 122 of two static contacts 12 are stacked together.

[0028] In this embodiment, the movable contact group is configured as one + two + one. Alternatively, it can be configured as one + two + two + one, with the middle movable contact 11 extended. This allows for three or more gaps between the intermediate plates, with a corresponding number of static contacts 12. This allows the entire circuit breaker contact clamping structure 1 to form a design combining parallel and series circuits, thereby enhancing short-time withstand performance.

[0029] The elastic clamping member in this embodiment uses a leaf spring 13, and the leaf spring 13 is installed on the outside of the clamping member 14 with the leaf arc inward. In order to facilitate the installation and fixation of the leaf spring, the top of the leaf spring 13 is provided with a through hole for fixing the clamping and fixing shaft 15, and the through hole is a gourd hole. The two ends of the clamping and fixing shaft 15 are provided with necks, and the necks are stuck in the small ends of the gourd hole. Of course, the fixing method of the clamping and fixing shaft 15 and the leaf spring 13 can also be any other suitable method. In this embodiment, the clamping member 14 is provided with a leaf spring fixing boss 141 outward at one end facing the static contact 12, and the edge of one end of the leaf spring 13 corresponding to the leaf spring fixing boss 141 of the clamping member 14 is provided with a notch that matches the shape of the corresponding surface of the leaf spring fixing boss 141. In this embodiment, the leaf spring fixing boss 141 is circular, and the notch that matches the shape of the corresponding surface of the leaf spring fixing boss 141 is a semicircular notch.

[0030] In order to keep the relative positions of the clamping member 14 and the moving contact 11 fixed, the clamping member 14 in this embodiment is further provided with bent wings 142 on both sides facing the moving contact 11. In this embodiment, the bent wings are rectangular, and the edges of the two side surfaces of the moving contact 11 are provided with notches corresponding to the shape and position of the bent wings 142. In this embodiment, the notches are rectangular grooves.

[0031] In this embodiment, in order to facilitate arc striking, arc striking angles 112 are further provided on the ends of the two middle moving contacts 11 facing the static contacts.

[0032] In the present application, in addition to using leaf springs 13, the elastic clamping member can also use other forms such as butterfly springs and diaphragm springs. The fixing method of the clamping member and the clamping fixing shaft can be adaptively modified. The contact clamping structure 1 of the circuit breaker of the present application can also be extended to other similar products such as circuit breakers that need to improve short-term resistance performance.

[0033] Based on the same inventive concept, the present application also provides a circuit breaker, comprising a base 4, an actuator 5, a rotating shaft 3, an upper cover 8 and two contact clamping structures 1 of the aforementioned circuit breakers, a plurality of flexible connections 17 and three terminal blocks 2. In this embodiment, the upper cover 8 is mounted on the base 4 through the middle cover 7. The middle cover 7 is also provided with a contour plate of the arc extinguishing chamber at the upper front end. Of course, under appropriate circumstances, the upper cover can also be directly mounted on the base 4. The actuator 5 is mounted within the upper cover 8. The rotating shaft 3 is mounted within the base 4 below the actuator 5 and is rotatable about the rotating shaft axis 31. In this embodiment, three mounting slots for the circuit breaker's contact clamping structure 1 are provided within the base 4. The terminal block 2 is mounted at one end of each mounting slot, and the mounting portion 122 of the static contact 12 of the circuit breaker's contact clamping structure 1 is mounted at the other end. Each moving contact 11 is electrically connected to the terminal block 2 within its respective mounting slot via a flexible connection 17. The circuit breaker's contact clamping structure 1 is mounted perpendicular to the overall direction of the rotating shaft 3 and is mounted within the corresponding mounting cavity of the rotating shaft 3 via a moving contact fixing shaft 16. The drawbar 6 passes through the two side plates of the actuator 5 and is mounted on the rear upper side of the rotating shaft 3. In this embodiment, the flexible connection 17 is welded to the terminal block 2 using copper stranded wire. That is, the four moving contacts 11 of each circuit breaker's contact clamping structure 1 are each welded to the terminal block 2 via a flexible connection 17 consisting of a copper stranded wire.

[0034] When the circuit breaker is open, the moving contact 11, the stationary contact 12, and the leaf spring 13 are free. When the circuit breaker is closed, the actuator 5 drives the rotating shaft 3, thereby driving the moving contact 11, so that the four moving contacts 11 of the two contact clamping structures 1 fit together with the two stationary contacts 12. The clamping member 14, the leaf spring 13, and the clamping and fixing shaft 15 secure the contacts together, preventing them from shifting. The force generated by the deformation of the leaf springs 13 on both sides provides pressure, improving the circuit breaker's short-circuit resistance.

[0035] In the description of this utility model, it should be noted that terms such as "center," "longitudinal," "transverse," "upper," "lower," "front," "back," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer" are used to indicate positions or relationships based on the positions or relationships shown in the accompanying drawings. These terms are used solely to facilitate the description of this utility model and to simplify the description. They do not indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on this utility model. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0036] The above is only a preferred specific implementation method of the present invention, but the protection scope of the present invention is not limited to this. Any technician familiar with the technical field within the technical scope disclosed by the present invention can make equivalent replacements or changes based on the technical solution and utility model concept of the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A contact clamping structure for a circuit breaker, comprising a stationary contact (12) and a strip-shaped moving contact (11), characterized in that: The invention also includes an elastic clamping member, a clamping member (14), a clamping fixing shaft (15), and a moving contact fixing shaft (16). The moving contact (11) includes a static contact clamping end and a distal clamping end. The number of the moving contacts (11) parallel to the plate surface is greater than 2, and the distal clamping end passes through the dynamic contact fixing shaft (16) to form a dynamic contact group, so that the gap between the plates is greater than 1. The static contact (12) includes an insertion portion (121) and a mounting portion (122). The number of the static contacts (12) is the same as the number of the gaps between the plates of the moving contacts (11). The thickness of the insertion portion (121) of the static contact (12) is greater than the gap distance between the plates when the switch is open, and the insertion end of the insertion portion (121) is provided with chamfered edges or chamfered arcs on both sides of the gap between the plates. When the switch is closed, the insertion of the static contact (12) is greater than the gap distance between the plates. The movable contact (11) extends into the inter-plate gap of the movable contact (11), the movable contact fixing shaft (16) is perpendicular to the plate surface of the movable contact (11), and a clamping member (14) is installed on the outer side of the clamping end of the two outermost movable contacts (11) of the movable contact group, and the clamping end of the movable contact (11) is provided with an isolation platform on the inner side of the inter-plate gap, and the height of the isolation platform in the inter-plate gap is less than the inter-plate gap when the switch is opened. Elastic clamping members are installed on the outer sides of the two clamping members (14), and the elastic clamping members clamp the extending portion of the static contact (12) extending into the inter-plate gap of the movable contact (11) when the switch is closed through the clamping member (14) through the clamping fixing shaft (15) passing through the movable contact (11), the clamping member (14) and the elastic clamping member, and the clamping fixing shaft (15) is perpendicular to the plate surface of the movable contact (11).

2. The contact clamping structure of the circuit breaker according to claim 1, characterized in that: The elastic clamping member uses a leaf spring (13), and the leaf spring (13) is installed on the outside of the clamping member (14) with its plate arc facing inward.

3. The contact clamping structure of the circuit breaker according to claim 2, characterized in that: The top of the leaf spring (13) is provided with a through hole for fixing and clamping the fixed shaft (15).

4. The contact clamping structure of the circuit breaker according to claim 3, characterized in that: The through hole is a gourd hole, and both ends of the clamping and fixing shaft (15) are provided with necks, which are clamped into the small end of the gourd hole.

5. The contact clamping structure of the circuit breaker according to claim 4, characterized in that: One end of the clamping member (14) is provided with a leaf spring fixing boss (141) facing outward, and an edge of one end of the leaf spring (13) corresponding to the leaf spring fixing boss (141) of the clamping member (14) is provided with a notch that matches the shape of the corresponding surface of the leaf spring fixing boss (141).

6. The contact clamping structure of a circuit breaker according to claim 1, characterized in that: The two side edges of the clamping piece (14) are provided with bent wings (142) facing the moving contact (11), and the two side edges of the moving contact (11) are provided with notches corresponding to the shape of the bent wings (142).

7. The contact clamping structure of a circuit breaker according to claim 1, characterized in that: An arc striking angle (112) is provided upwardly at the end of the moving contact (11) facing the static contact.

8. The contact clamping structure of a circuit breaker according to claim 1, characterized in that: The mounting portion (122) of each static contact (12) is perpendicular to the extending portion (121), and the mounting portion (122) of each static contact (12) is stacked together.

9. The contact clamping structure of a circuit breaker according to claim 1, characterized in that: The moving contact (11) consists of four pieces, with the two middle pieces stacked together.

10. A circuit breaker comprising a base (4), an actuator (5), a rotating shaft (3), and an upper cover (8), characterized in that: It also includes a contact clamping structure (1), a soft connection (17) and a terminal block (2) of a circuit breaker according to any one of claims 1 to 9, wherein the upper cover (8) is directly or indirectly mounted on the base (4), the actuator (5) is mounted in the upper cover (8), the rotating shaft (3) is mounted in the base (4) below the actuator (5), and a plurality of mounting slots for mounting the contact clamping structure (1) of the circuit breaker are provided in the base (4), the terminal block (2) is mounted at one end of the mounting slot, and the mounting portion (122) of the static contact (12) of the contact clamping structure (1) of the circuit breaker is mounted at the other end of the mounting slot, each of the moving contacts (11) is electrically connected to the terminal block (2) in its respective mounting slot via a soft connection (17), and the mounting direction of the contact clamping structure (1) of the circuit breaker is perpendicular to the overall direction of the rotating shaft (3) and is mounted in the mounting cavity corresponding to the rotating shaft (3) via a moving contact fixing shaft (16).

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