Tripping mechanism for preventing contact from falling back of circuit breaker

Abstract

The utility model relates to a tripping mechanism of a circuit breaker, in particular to a tripping mechanism of a circuit breaker for preventing a contact from falling back, which is assembled in the circuit breaker, and the circuit breaker comprises a static contact, a moving contact, a traction rod, a rotating shaft seat, an operating mechanism, a tripping mechanism and a shell, the tripping mechanism comprises a linkage lever, a tripping lever and a tripping spring; the moving contact is movably connected with the rotating shaft seat through the moving contact bridge rotating shaft; the tripping lever is movably connected with the rotating shaft seat through the rotor shaft; one end of the linkage lever is movably connected with the rotating shaft seat, and the other end of the linkage lever abuts against the tripping lever. The tripping spring is mounted on the rotating shaft seat and is pressed at one end of the tripping spring; the traction rod and the rotating shaft seat are in transmission connection with an operating mechanism. Compared with the prior art, the utility model solves the problem that the moving contact of the existing high-capacity circuit breaker is easy to fall back, and realizes that the tripping mechanism of the operating mechanism of the high-capacity circuit breaker can be accurately and quickly unlocked after the contact is separated due to electric repulsive force.

Description

Technical Field

[0001] The utility model relates to a tripping mechanism of a circuit breaker, in particular to a tripping mechanism for preventing the contact of the circuit breaker from falling back. Background Art

[0002] Existing molded case circuit breakers usually have a current limiting function. When a short circuit occurs in the circuit, the moving contact of the circuit breaker is repelled and an arc is generated in a very short time under the action of the electric repulsive force, thereby limiting the further rise of the short circuit current. As the separation distance between the moving and static contacts increases, the electric repulsive force rapidly decreases. When the electric repulsive force is less than the reaction force of the contact spring, the moving and static contacts begin to approach. This kind of approach is called "the falling back of the contact", which will have an adverse impact on the circuit breaker, such as: prolonging the breaking time, causing the re-ignition of the arc in the arc extinguishing chamber, and seriously burning out the circuit breaker, thus affecting the breaking ability of the circuit breaker.

[0003] In small-capacity circuit breakers, a general solution is to use an electromagnet to actuate and quickly unlock the operating mechanism of the circuit breaker. When a short circuit occurs in the circuit, the operating mechanism of the circuit breaker is quickly actuated to separate the moving and static contacts, thereby avoiding the phenomenon of "the falling back of the contact" of the repelled contacts.

[0004] However, in large-capacity circuit breakers, due to space limitations, the size of the electromagnet is restricted, and the electromagnet is extremely easy to saturate, thus affecting the action speed of the operating mechanism of the circuit breaker and causing the repelled moving contact to appear the phenomenon of "the falling back of the contact" again.

[0005] The prior art CN103928272A discloses a circuit breaker structure and a circuit breaker that use electric repulsive force to quickly trip. Under the action of the electric repulsive force, the moving contact rotates and drives the first connecting rod and the second connecting rod to rotate, and then pushes the traction rod to actuate and trigger the tripping of the operating mechanism. Since this scheme adopts a lever structure hinged to the moving contact, there is a possibility that when the repelling angle of the moving contact is not large enough, the intermediate connecting rod cannot reach the position to push the traction rod, resulting in the phenomenon of "the falling back of the contact" still occurring.

[0006] Therefore, a tripping mechanism that can accurately and quickly unlock the operating mechanism of a large-capacity circuit breaker after the contacts are separated due to electric repulsive force is needed. Summary of the Utility Model

[0007] The purpose of the utility model is to provide a tripping mechanism for preventing the contact of the circuit breaker from falling back to solve at least one of the above problems, so as to solve the problem that the repelled moving contact of the large-capacity circuit breaker in the prior art is prone to the phenomenon of "the falling back of the contact". This scheme realizes a tripping mechanism that can accurately and quickly unlock the operating mechanism of the large-capacity circuit breaker after the contacts are separated due to electric repulsive force.

[0008] The purpose of the utility model is achieved through the following technical solutions:

[0009] A tripping mechanism for preventing a circuit breaker from contacting and falling back is installed in the circuit breaker. The circuit breaker comprises a stationary contact, a moving contact, a traction rod, a rotating shaft seat, an operating mechanism, a tripping mechanism and a housing.

[0010] The release mechanism comprises a linkage lever, a release lever and a release spring;

[0011] The moving contact is movably connected to the rotating shaft seat via the moving contact bridge rotating shaft;

[0012] The release lever is movably connected to the rotating shaft seat through the rotor shaft;

[0013] One end of the linkage lever is movably connected to the rotating shaft seat, and one end of the linkage lever abuts against the release lever;

[0014] The release spring is installed on the rotating shaft seat, and the release lever is pressed on one end of the release spring;

[0015] The traction rod and the rotating shaft seat are transmission-connected with the operating mechanism;

[0016] When the circuit breaker is in the closed state: the static contact is coupled with the moving contact, the other end of the linkage lever abuts against the moving contact, and no interaction force is generated between the traction rod and the tripping lever;

[0017] When the static contact and the moving contact are separated: the tripping lever unlocks the operating mechanism through the transmission traction rod, and the operating mechanism drives the rotating shaft seat to rotate in the direction away from the static contact, so that the static contact and the moving contact remain disconnected.

[0018] Specifically, when the circuit breaker is tripped, the specific action process is as follows: under the action of the electric repulsive force, the moving contact rotates in the first direction away from the static contact, and pushes the linkage lever to rotate in the first direction, and the linkage lever then pushes the trip lever to rotate in the first direction and squeezes the trip spring; when the linkage lever rotates in the first direction to an angle less than 90° with the trip lever, the trip spring is released to cause the trip lever to rotate in the second direction, and the trip lever pushes the traction rod to rotate in the first direction, and the traction rod then drives the operating mechanism to rotate in the first direction; the operating mechanism then drives the rotating shaft seat to rotate in the first direction, so that the static contact and the moving contact remain in a disconnected state.

[0019] Preferably, the moving contact comprises a first limiting surface, a mounting hole and an abutting surface;

[0020] The mounting hole is arranged at the tail end of the moving contact, and the rotating shaft of the moving contact bridge is assembled in the mounting hole;

[0021] The linkage lever abuts against the abutting surface, and when the circuit breaker is in the closed state, the linkage lever abuts against the first limiting surface, so that the rotation of the linkage lever towards the second direction is restricted by the blocking of the first limiting surface.

[0022] Preferably, the linkage lever includes a lever frame, a convex platform, a push rod and an abutting rod;

[0023] The convex platform is arranged on both sides of one end of the lever frame and is movably connected to the rotating shaft seat;

[0024] The push rod is arranged at one end of the lever frame, and the push rod abuts against the tripping lever; the abutting rod is arranged at the other end of the lever frame, and the abutting rod abuts against the moving contact; the push rod and the abutting rod are arranged opposite to each other.

[0025] Preferably, the linkage lever further includes a reinforcing load-bearing column;

[0026] The reinforcing load-bearing column straddles between one end and the other end inside the lever frame;

[0027] At least one pair of reinforcing load-bearing columns is provided.

[0028] Preferably, the tripping lever includes an abutting arm, a tripping arm, a top block and a through hole;

[0029] An obtuse angle is formed between the abutting arm and the tripping arm, and the length of the abutting arm is shorter than that of the tripping arm;

[0030] One end of the linkage lever abuts against the outside of the abutting arm;

[0031] The top block is arranged on the tripping arm, and the top block extends outwards and presses against one end of the tripping spring;

[0032] A through hole is formed at the connection between the abutting arm and the tripping arm, and the rotor shaft is assembled in the through hole.

[0033] Preferably, the tripping spring includes a spring seat and a spring;

[0034] The spring seat has a "convex" structure, forming a cavity for accommodating the spring;

[0035] The spring is arranged in the rotating shaft seat, and the spring seat is limited on the rotating shaft seat;

[0036] The tripping lever presses against the spring seat.

[0037] Preferably, the rotating shaft seat includes a first assembly hole, a second assembly hole, a third assembly hole and a groove;

[0038] The described first assembly hole is opened on the side wall of the rotating shaft seat and is used to connect the linkage lever; the described second assembly hole is opened on the side wall of the rotating shaft seat and is used to connect the tripping lever; the described third assembly hole is opened on the side wall of the rotating shaft seat and is used to connect the moving contact.

[0039] The described groove is opened on the rotating shaft seat and is used to install the tripping spring.

[0040] Preferably, an installation groove is further provided at the first assembly hole; the installation groove is inclined, and one end of the installation groove extends to the side of the rotating shaft seat.

[0041] Preferably, the rotor shaft includes a main body section, a first reduced-diameter section, a second reduced-diameter section, and a retaining ring groove.

[0042] The first reduced-diameter section is connected to the end of the main body section and is used to connect the tripping lever.

[0043] The retaining ring groove is arranged on the first reduced-diameter section and is used to install a retaining ring to axially limit the tripping lever.

[0044] The second reduced-diameter section is connected to the end of the main body section and / or the first reduced-diameter section and is used to connect the rotating shaft seat.

[0045] Preferably, the circuit breaker includes several phases, and several moving contacts are correspondingly arranged for each phase. Several rotating shaft seats are arranged side by side corresponding to the number of phases. One linkage lever and one tripping lever are correspondingly arranged for each phase; the linkage lever is in contact with each moving contact in the corresponding phase simultaneously when the circuit breaker is closed, and each tripping lever is in transmission connection with the traction rod.

[0046] Compared with the prior art, the utility model has the following beneficial effects:

[0047] (1) In terms of structure, the patented technology uses the breaking method of driving the tripping device by the moving contact itself. Compared with the conventional breaking method of using an electromagnet to drive the tripping device in the prior art, the response speed is faster, which can effectively prevent the falling back of the moving contact and improve the breaking reliability of the circuit breaker.

[0048] (2) The patented technology adopts a special lever mechanism. By contacting each moving contact through the linkage lever, when any moving contact is repelled, it will drive the operating mechanism to trip, avoiding the phenomenon of "falling back of the contact" of the repelled contact again. In the prior art, only when a designated moving contact in each phase bounces, the operating mechanism will be driven to trip. The improvement of the prior art improves the breaking reliability of the product.

[0049] (3) The patented technology utilizes the elastic force of a spring. Compared with the mechanism without a spring in the prior art, through the action of the elastic force of the spring, when the repulsion movement of the moving contact reaches a certain angle, the elastic force released by the spring can be fully utilized to more quickly and accurately unlock the circuit breaker operating mechanism, thereby improving the breaking speed of the circuit breaker operating mechanism.

[0050] (4) The structure of the patented technology is relatively simple and easy to install.

[0051] Compared with the prior art (CN103928272A), this solution adopts the form of a lever plus a spring, and can utilize the elastic force released by the spring to more quickly and accurately unlock the circuit breaker operating mechanism, improving the sectional speed of the circuit breaker operating mechanism. Description of the Drawings

[0052] Figure 1 Structural schematic diagram when the circuit breaker is in the closing state;

[0053] Figure 2 Structural schematic diagram in the first state when the circuit breaker trips;

[0054] Figure 3 Structural schematic diagram in the second state when the circuit breaker trips;

[0055] Figure 4 Structural schematic diagram when the circuit breaker is fully tripped;

[0056] Figure 5 Assembly schematic diagram of the linkage lever, trip lever, rotor shaft and trip spring;

[0057] Figure 6 Structural schematic diagram of the moving contact;

[0058] Figure 7 Structural schematic diagram of the linkage lever;

[0059] Figure 8 Structural schematic diagram of the trip lever;

[0060] Figure 9 Structural schematic diagram of the spring seat;

[0061] Figure 10 Structural schematic diagram of the rotating shaft seat, a, rear view, b, side view;

[0062] Figure 11 Structural schematic diagram of the rotor shaft;

[0063] Figure 12 Structural schematic diagram of the traction rod;

[0064] Figure 13 Structural schematic diagram of the trip mechanism;

[0065] In the figure: 1 - operating mechanism; 2 - static contact; 3 - moving contact; 4 - linkage lever; 5 - traction rod; 6 - tripping lever; 7 - tripping spring; 8 - rotating shaft seat; 9 - rotating shaft of moving contact bridge; 10 - rotor shaft; 11 - insulating plug; 12 - middle sleeve; 13 - retaining ring; 31 - first limiting surface; 32 - mounting hole; 33 - abutting surface; 41 - boss; 411 - hemispherical surface; 42 - ejector rod; 43 - abutting rod; 44 - reinforcing load-bearing column; 51 - passive part; 61 - abutting arm; 62 - tripping arm; 63 - top block; 64 - through hole; 71 - spring seat; 711 - convex surface; 712 - long end surface; 713 - short end surface; 72 - spring; 81 - first assembly hole; 82 - second assembly hole; 83 - third assembly hole; 84 - sliding groove; 85 - spring groove; 86 - second limiting surface; 87 - mounting groove; 101 - first reduced-diameter section; 102 - second reduced-diameter section; 103 - retaining ring groove. Detailed implementation mode

[0066] The present utility model will be described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0067] Embodiment 1

[0068] A tripping mechanism for preventing the contact of a circuit breaker from falling back, as Figures 1-13 shown, is assembled in a circuit breaker. The circuit breaker includes a static contact 2, a moving contact 3, a traction rod 5, a rotating shaft seat 8, an operating mechanism 1, a tripping mechanism, and a housing (including a base and a middle sleeve 12);

[0069] The tripping mechanism includes a linkage lever 4, a tripping lever 6, and a tripping spring 7;

[0070] The moving contact 3 is movably connected to the rotating shaft seat 8 through the rotating shaft of the moving contact bridge 9;

[0071] The tripping lever 6 is movably connected to the rotating shaft seat 8 through the rotor shaft 10;

[0072] One end of the linkage lever 4 is movably connected to the rotating shaft seat 8, and one end of the linkage lever 4 abuts against the tripping lever 6;

[0073] The tripping spring 7 is installed on the rotating shaft seat 8, and the tripping lever 6 is pressed against one end of the tripping spring 7;

[0074] The traction rod 5 and the rotating shaft seat 8 are in transmission connection with the operating mechanism 1;

[0075] When the circuit breaker is in the closed state: the static contact 2 is coupled with the moving contact 3, the other end of the linkage lever 4 abuts against the moving contact 3, and there is no mutual acting force between the traction rod 5 and the tripping lever 6;

[0076] When the static contact 2 and the moving contact 3 are repelled: The tripping lever 6 unlocks the operating mechanism 1 through the transmission traction rod 5. The operating mechanism 1 drives the rotating shaft seat 8 to rotate away from the static contact 2, keeping the static contact 2 and the moving contact 3 disconnected.

[0077] Specifically, when the circuit breaker trips, the specific action process is as follows: Under the action of the electric repulsive force, the moving contact 3 rotates away from the static contact 2 in the first direction (counterclockwise, the same below) and pushes the linkage lever 4 to rotate in the first direction. The linkage lever 4 then pushes the tripping lever 6 to rotate in the first direction and compress the tripping spring 7; when the angle between the linkage lever 4 and the tripping lever 6 is less than 90° when rotating in the first direction, the tripping spring 7 is released, causing the tripping lever 6 to rotate in the second direction (clockwise). The tripping lever 6 pushes the traction rod 5 to rotate in the first direction, and the traction rod 5 drives the operating mechanism 1 to rotate in the first direction; the operating mechanism 1 drives the rotating shaft seat 8 to rotate in the first direction, keeping the static contact 2 and the moving contact 3 in a disconnected state.

[0078] More specifically, in this embodiment:

[0079] The component structure in this circuit breaker includes:

[0080] The static contact 2 is installed on the base of the circuit breaker housing.

[0081] The moving contact 3, as Figure 6 shown, has a moving contact at its head end, and a contact surface 33 is set on the upper side of the head (when the circuit breaker is closed, it abuts against one end of the linkage lever 4). On the upper side of the tail, a first limit surface 31 is set higher than the contact surface 33 (for blocking the further rotation of the linkage lever 4 in this direction), and an installation hole 32 is opened at the tail end (for assembling the moving contact bridge rotating shaft 9). In the circuit breaker, there are several phases (usually three phases), and each phase is composed of five moving contacts 3. The five moving contacts 3 are movably installed in the rotating shaft seat 8 through the moving contact bridge rotating shaft 9 inserted into the installation holes 32 at the tail ends so that they can rotate.

[0082] The linkage lever 4, as Figure 7 shown, the overall frame is composed of a pair of cuboids (left and right sides) and a pair of cylinders (front and back pairs of sides). At both ends of one side of the frame, there are respectively provided bosses 41 (for movably assembling with the rotating shaft seat 8), and on this side, there is also provided an outwardly extending ejector rod 42, which is inclined upward (for abutting against the tripping lever 6); hemispherical surfaces 411 are respectively provided at both ends of the boss 41 to facilitate the assembly between the linkage lever 4 and the rotating shaft seat 8. The other side (cylinder) of the frame is set as an abutting rod 43 (when the circuit breaker is closed, it abuts against the contact surface 33 of each moving contact 3 in one phase), and a pair of reinforcing load-bearing columns 44 are symmetrically arranged in the middle of the frame (a pair of cylinders) (for improving the structural strength).

[0083] The trip lever 6, as Figure 8 shown, consists of a long arm and a short arm with an obtuse angle between them. The shorter end is the abutting arm 61 (the outer side abuts against the ejector rod 42 of the linkage lever 4), and the longer end is the trip arm 62. There is a protruding top block 63 (pressed against one end of the trip spring 7) on the outer side of the trip arm 62, and a hook structure is designed at the free end of the trip arm 62 (for transmission with the traction rod 5); a through hole 64 is also opened at the connection of the two arms (for installing the rotor shaft 10 and movably connecting with the rotating shaft seat 8 through the rotor shaft 10).

[0084] The trip spring 7, as Figure 9 shown, is jointly composed of a spring seat 71 and a spring 72. The spring seat 71 is bent in a "convex" shape, including the protruding surface 711 therein and the long end surfaces 712 and short end surfaces 713 connected to both sides of the protruding surface 711; a cavity for placing the spring 72 is formed inside the "convex" bend.

[0085] The rotating shaft seat 8, as Figure 10 shown, is arranged in parallel according to the number of phases of the circuit breaker. On the side wall of the rotating shaft seat 8 of each phase, there are pairs of first assembly holes 81 (for installing the linkage lever 4), relatively larger and paired second assembly holes 82 (for installing the trip lever 6), and relatively lower and paired third assembly holes 83 (for installing the moving contact 3). There are also a laterally extending sliding groove 84 and a vertical spring groove 85 (for accommodating the spring 72) behind the rotating shaft seat 8 of each phase. Among them, second limiting surfaces 86 (for installing and limiting the spring seat 71) are provided at the tops of both ends of the sliding groove 84. In addition, for the convenience of assembly, an installation groove 87 with a depth less than that of the first assembly hole 81 and extending obliquely upward is opened at the first assembly hole 81, and the installation groove 87 extends to the side of the rotating shaft seat 8 to facilitate the convex platform 41 of the linkage lever 4 to slide in.

[0086] The rotor shaft 10, as Figure 11 shown, is designed with a first reduced-diameter section 101 (for sleeving the trip lever 6) and a second reduced-diameter section 102 (for sleeving the insulating plug 11 to prevent current short circuit between adjacent phases; during assembly, first install the rotor shaft 10 into the rotating shaft seat 8, and then install the insulating plug 11). Among them, the diameter of the first reduced-diameter section 101 is larger than that of the second reduced-diameter section 102. The first reduced-diameter section 101 is connected to both ends of the main body section, and the second reduced-diameter section 102 is connected to both ends of the main body section and / or the first reduced-diameter section 101. A snap ring groove 103 is also opened on the first reduced-diameter section 101 for assembling a snap ring 13 (using an open-loop snap ring 13). According to the positions of different phases in the circuit breaker, both ends of the rotor shaft 10 of the middle phase are provided with the second reduced-diameter section 102, and only one end of the rotor shaft 10 of other phases is provided with the second reduced-diameter section 102.

[0087] The structure assembly of the circuit breaker is as follows: Figure 1 and Figure 13 As shown:

[0088] The circuit breaker includes a static contact 2, a moving contact 3, a traction rod 5, a rotating shaft seat 8, an operating mechanism 1, a tripping mechanism and a housing (including a base and a middle sleeve 12), and the tripping mechanism specifically includes a linkage lever 4, a traction rod 5, a tripping lever 6 and a tripping spring 7.

[0089] The stationary contact 2 is mounted on the base, and one end of the moving contact 3 with the moving contact is located above the stationary contact 2. In the closed state, the moving contact of the moving contact 3 is coupled with the stationary contact of the stationary contact 2 ( Figure 1 The other end of the moving contact 3 is hinged on the rotating shaft seat 8 through the mounting hole 32 via the moving contact bridge rotating shaft 9 through the third assembly hole 83.

[0090] The bosses 41 at both ends of the linkage lever 4 slide through the mounting grooves 87 on the shaft seat 8 and are inserted into the first assembly hole 81, so that the linkage lever 4 is connected to the shaft seat 8. The top rod 42 of the linkage lever 4 abuts against the outer side of the abutment arm 61 of the trip lever 6, and the abutment rod 43 abuts against the abutment surface 33 of the moving contact 3 in the closed state, and is restricted from unidirectional rotation by the first limit surface 31.

[0091] The trip lever 6 is inserted into the first diameter-reducing section 101 of the rotor shaft 10 through the through hole 64, and the open retaining ring 13 is installed in the retaining ring groove 103 to prevent the trip lever 6 from shaking left and right on the rotor shaft 10; further, the rotor shaft 10 is hinged on the rotating shaft seat 8 through the second assembly hole 82. The top block 63 on the trip lever 6 is in contact with the raised surface 711 of the spring seat 71, and the spring 72 is assembled in the cavity formed by the spring seat 71. The trip lever 6 can compress the spring 72 by rotating and squeezing the spring seat 71.

[0092] The spring seat 71 of the release spring 7 is placed in the sliding groove 84 of the rotating shaft seat 8 through its long end surface 712 and short end surface 713, and the spring seat 71 is reliably assembled by the second limiting surface 86; the spring 72 is placed in the spring groove 85 of the rotating shaft seat 8.

[0093] The traction rod 5 and the rotating shaft seat 8 are respectively connected to the operating mechanism 1 in a transmission manner, wherein the traction rod 5 is installed on the operating mechanism 1. Figure 12 The traction rod 5 has three passive parts 51 extending toward the tripping lever 6. In the closed state, the passive parts 51 and the tripping lever 6 are in contact with each other and no force is generated between them. During the tripping process, the tripping lever 6 pushes the passive parts 51 to drive the traction rod 5 to unlock the operating mechanism 1. Finally, the operating mechanism 1 drives the rotating shaft seat 8 to rotate, so that the static contact 2 and the moving contact 3 remain in the disconnected state.

[0094] As shown Figure 13 in the figure, a three-phase structural situation is shown, where each phase includes 5 moving contacts 3, 1 linkage lever 4, and 1 tripping lever 6; 3 corresponding passive parts 51 protrude from the traction rod 5 to form a transmission connection with the tripping lever 6; when the circuit breaker is in the closed state, the linkage lever 4 in each phase is in contact with the contact surfaces 33 of the moving contacts 3 in this phase, each tripping lever 6 is in contact with the linkage lever 4 of the corresponding phase, and the passive parts 51 of each traction rod 5 cooperate with the tripping lever 6 of the corresponding phase respectively. By unlocking the operating mechanism 1 through the traction rod 5, finally the operating mechanism 1 drives the rotating shaft seat 8 to rotate, so that the static contact 2 and the moving contact 3 are kept in the disconnected state.

[0095] Functions and working principles of the main components in this device:

[0096] In the closed state, the operating mechanism 1 is in the locked state, the static contact 2 and the moving contact 3 are coupled, the linkage lever 4 and the tripping lever 6 act on each other, and the linkage lever 4 is blocked by the first limiting surface 31, so that the two levers (linkage lever 4 and tripping lever 6) are kept in a balanced state. At this time, the spring 72 is squeezed by the force transmitted through the spring seat 71 by the top block 63 on the tripping lever 6, and there is no acting force between the tripping arm 62 and the traction rod 5 (as Figure 1 shown, the traction rod 5 and the hook structure at the end of the tripping arm 62 are in contact with each other without generating an acting force).

[0097] When any moving contact 3 bounces due to the electric repulsive force, the moving contact 3 is disconnected from the static contact 2. As the moving contact 3 rises, the contact surface 33 pushes the linkage lever 4 to rotate clockwise. When the angle between the ejector rod 42 and the contact arm 61 of the tripping lever 6 reaches 90°, the spring 72 is squeezed the most ( Figure 2 ).

[0098] As the linkage lever 4 continues to rotate clockwise, when the angle between the ejector rod 42 and the contact arm 61 is less than 90°, at this time, the pressure applied to the spring 72 disappears, and the spring 72 instantaneously releases its elastic force, causing the tripping lever 6 to rotate counterclockwise and pushing the traction rod 5 to rotate clockwise to unlock the operating mechanism 1 ( Figure 3 ).

[0099] The rotating shaft seat 8 is further driven by the operating mechanism 1 to rotate clockwise, so that the static contact 2 and the moving contact 3 are kept in the disconnected state. The end position of the movement of the linkage lever 4 depends on the middle sleeve 12 of the circuit breaker. At this time, the upward force of the spring 72 pushes the tripping lever 6 to maintain a tendency to rotate counterclockwise ( Figure 4 ). When closing again, the tripping lever 6 pushes the linkage lever 4 to rotate counterclockwise, so that the angle between the ejector rod 42 and the contact arm 61 returns to the original angle to achieve reset.

[0100] The above description of the embodiments is to enable those of ordinary skill in the art to understand and use the utility model. It is obvious that those skilled in the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative efforts. Therefore, the utility model is not limited to the above embodiments, and all improvements and modifications made by those skilled in the art without departing from the scope of the utility model according to the disclosure of the utility model should be within the protection scope of the utility model.

Claims

1. A tripping mechanism for preventing contact from falling back of a circuit breaker, assembled in the circuit breaker, characterized in that: The circuit breaker comprises a stationary contact (2), a moving contact (3), a traction rod (5), a rotating shaft seat (8), an operating mechanism (1), a tripping mechanism and a housing; The release mechanism comprises a linkage lever (4), a release lever (6) and a release spring (7); The moving contact (3) is movably connected to the rotating shaft seat (8) via the moving contact bridge rotating shaft (9); The release lever (6) is movably connected to the rotating shaft seat (8) via the rotor shaft (10); One end of the linkage lever (4) is movably connected to the rotating shaft seat (8), and one end of the linkage lever (4) abuts against the release lever (6); The release spring (7) is mounted on the rotating shaft seat (8), and the release lever (6) is pressed on one end of the release spring (7); The traction rod (5) and the rotating shaft seat (8) are transmission-connected to the operating mechanism (1); When the circuit breaker is in a closed state: the static contact (2) is coupled with the moving contact (3), the other end of the linkage lever (4) abuts against the moving contact (3), and no interaction force is generated between the traction rod (5) and the tripping lever (6); When the stationary contact (2) and the moving contact (3) are separated, the tripping lever (6) unlocks the operating mechanism (1) through the transmission traction rod (5), and the operating mechanism (1) drives the rotating shaft seat (8) to rotate in a direction away from the stationary contact (2), so that the stationary contact (2) and the moving contact (3) remain disconnected.

2. A tripping mechanism for preventing contact from falling back of a circuit breaker according to claim 1, characterized in that: The moving contact (3) comprises a first limiting surface (31), a mounting hole (32) and an abutting surface (33); The mounting hole (32) is arranged at the rear end of the moving contact (3), and the moving contact bridge rotating shaft (9) is assembled in the mounting hole (32); The linkage lever (4) abuts against the abutment surface (33), and when the circuit breaker is in a closed state, the linkage lever (4) abuts against the first limit surface (31).

3. A tripping mechanism for preventing contact from falling back of a circuit breaker according to claim 1, characterized in that: The linkage lever (4) comprises a lever frame, a boss (41), a push rod (42) and an abutment rod (43); The boss (41) is arranged on both sides of one end of the lever frame and is movably connected to the rotating shaft seat (8); The push rod (42) is arranged at one end of the lever frame, and the push rod (42) abuts against the tripping lever (6); the abutting rod (43) is arranged at the other end of the lever frame, and the abutting rod (43) abuts against the moving contact (3); the push rod (42) and the abutting rod (43) are arranged opposite to each other.

4. A tripping mechanism for preventing contact from falling back of a circuit breaker according to claim 3, characterized in that: The linkage lever (4) further comprises a reinforcement load-bearing column (44); The reinforced load-bearing column (44) is arranged between one end and the other end inside the lever frame; At least one pair of the reinforced load-bearing columns (44) is provided.

5. A tripping mechanism for preventing contact from falling back of a circuit breaker according to claim 1, characterized in that: The release lever (6) comprises an abutment arm (61), a release arm (62), a top block (63) and a through hole (64); The abutment arm (61) and the release arm (62) are arranged at an obtuse angle, and the length of the abutment arm (61) is shorter than the length of the release arm (62); One end of the linkage lever (4) abuts against the outer side of the abutment arm (61); The top block (63) is arranged on the release arm (62), and the top block (63) extends outward and is pressed against one end of the release spring (7); A through hole (64) is provided at the connection between the abutment arm (61) and the release arm (62), and the rotor shaft (10) is assembled in the through hole (64).

6. A tripping mechanism for preventing contact from falling back of a circuit breaker according to claim 1, characterized in that: The release spring (7) comprises a spring seat (71) and a spring (72); The spring seat (71) is a "convex"-shaped structure, forming a cavity for accommodating the spring (72); The spring (72) is arranged in the rotating shaft seat (8), and the spring seat (71) is limited on the rotating shaft seat (8); The release lever (6) is pressed onto the spring seat (71).

7. A tripping mechanism for preventing contact from falling back of a circuit breaker according to claim 1, characterized in that: The rotating shaft seat (8) comprises a first assembly hole (81), a second assembly hole (82), a third assembly hole (83) and a groove; The first assembly hole (81) is formed on the side wall of the rotating shaft seat (8) and is used to connect the linkage lever (4); the second assembly hole (82) is formed on the side wall of the rotating shaft seat (8) and is used to connect the release lever (6); the third assembly hole (83) is formed on the side wall of the rotating shaft seat (8) and is used to connect the moving contact (3); The groove is formed on the rotating shaft seat (8) and is used for installing the release spring (7).

8. A tripping mechanism for preventing contact from falling back of a circuit breaker according to claim 7, characterized in that: The first assembly hole (81) is also provided with a mounting groove (87); the mounting groove (87) is arranged obliquely, and one end of the mounting groove (87) extends to the side of the rotating shaft seat (8).

9. A tripping mechanism for preventing contact from falling back of a circuit breaker according to claim 1, characterized in that: The rotor shaft (10) comprises a main body section, a first diameter-reducing section (101), a second diameter-reducing section (102) and a retaining ring groove (103); The first diameter-reducing section (101) is connected to the end of the main body section and is used for connecting the tripping lever (6); The retaining ring groove (103) is arranged on the first diameter-changing section (101) and is used to install the retaining ring (13) to axially limit the release lever (6); The second diameter-reducing section (102) is connected to the main section and / or the end of the first diameter-reducing section (101) and is used for connecting to the rotating shaft seat (8).

10. A tripping mechanism for preventing contact from falling back of a circuit breaker according to claim 1, characterized in that: The circuit breaker comprises a plurality of phases, each phase being provided with a plurality of moving contacts (3), a plurality of rotating shaft seats (8) being provided in parallel corresponding to the number of phases, and a linkage lever (4) and a release lever (6) being provided corresponding to each phase; the linkage lever (4) abuts against each moving contact (3) in the corresponding phase simultaneously when the circuit breaker is closed, and each release lever (6) is transmission-connected to a traction rod (5).

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