A high current molded case circuit breaker operating mechanism

Abstract

This invention discloses an operating mechanism for a high-current molded case circuit breaker, comprising a latching assembly, a tripping assembly, a handle driving assembly, and a mechanism spring mounted on the mechanism frame. The tripping assembly includes a rotatably mounted tripping member and a locking groove and a limiting structure mounted on the tripping member. The tripping member forms a locking engagement with the latching assembly through the locking groove. When the operating mechanism trips, the tripping member, through the limiting structure and the latching assembly, precisely restricts the tripping member to a preset second position, thereby actively controlling the maximum rebound stroke and final stop position of the tripping member. This ensures that a preset gap is always maintained between the tripping member and the mechanism push rod. This design not only ensures that the handle driving assembly can accurately reset after tripping, but also eliminates the sense of resistance and jamming during the operation of the mechanism, extends the service life, and improves the reliability and stability of the high-current molded case circuit breaker during long-term operation.

Description

Technical Field

[0001] This invention relates to the field of low-voltage electrical appliance technology, and more specifically to an operating mechanism for a high-current molded case circuit breaker. Background Technology

[0002] Molded case circuit breakers (MCCBs) are key protective components in low-voltage power distribution systems, widely used for overload and short-circuit protection of power lines and equipment in industrial, commercial, and high-rise building sectors. With the continuous increase in electrical load, the application of high-current MCCBs with rated currents up to 1600A is becoming increasingly widespread. The operating mechanism is the core component of the circuit breaker, responsible for performing opening, closing, and tripping actions; its performance directly determines the reliability and safety of the circuit breaker's operation.

[0003] Existing high-current molded case circuit breaker operating mechanisms are typically assembled from components such as trip latches, locking latches, handle levers, traction rods, and main tension springs. Their working principle is as follows: In circuit breakers with thermal-magnetic protection, when a line fault occurs, the thermal-magnetic tripping mechanism triggers the traction rod to rotate. The traction rod releases the locking latch assembly, which, under spring force, quickly separates from the trip latch, triggering the tripping action of the operating mechanism and tripping the circuit breaker. After tripping, high-current molded case circuit breakers require a re-clamping process during closing. This involves using a push rod on the handle lever to apply pressure to the top of the trip latch, which, through the locking latch, re-restricts the trip latch's freedom of movement, preparing the mechanism for the next closing operation.

[0004] However, in practical applications, the operating mechanisms of existing high-current circuit breakers have the following problems: Due to the large rated current of the circuit breaker, the opening and closing operating force required by the operating mechanism is also correspondingly large. At the moment of circuit breaker tripping, the trip lever moves rapidly away from the locking lever under the action of the powerful main tension spring. Affected by this huge spring force, the rebound distance of the trip lever is too large, and the movement trajectory is difficult to control precisely. This causes the original design clearance between the trip lever and the handle lever to be disrupted, resulting in unexpected interference contact between the trip lever and the push rod of the handle lever after the trip lever rebounds. This interference not only causes the handle to be in the wrong opening and closing position, affecting the accuracy of the status indication; more seriously, during the re-clamping and closing operation of the operating mechanism through the handle, a noticeable sense of resistance and jamming will occur, seriously affecting the operating feel and user experience. Over time, this may also accelerate the wear of parts, reduce the service life of the mechanism, and reduce the overall reliability of the circuit breaker. Summary of the Invention

[0005] Therefore, the technical problem to be solved by the present invention is to overcome the problem in the prior art where the snap-back unexpectedly interferes with the push rod of the mechanism after rebounding, which not only causes the handle to be in an incorrect position when opening or closing the circuit, but also produces obvious resistance and jamming in the operation of the mechanism, thus reducing the service life of the operating mechanism.

[0006] To address the aforementioned problems, the present invention provides an operating mechanism for a high-current molded case circuit breaker, comprising a mechanism frame and a locking assembly, a tripping assembly, a handle drive assembly, and a mechanism spring disposed on the mechanism frame; the tripping assembly includes a tripping member rotatably disposed on the mechanism frame, the tripping member being provided with a locking groove and a limiting structure, and the mechanism spring connecting the tripping assembly and the handle drive assembly; The handle drive assembly includes a handle lever and a mechanism push rod that are linked together. The handle lever is reciprocatingly oscillating on the mechanism frame, and the mechanism push rod is connected to the top of the jump fastener. The locking assembly is rotatably mounted on the frame and connected between the jump fastener and the traction rod; the jump fastener has a first position that forms a locking engagement with the locking assembly and a second position that forms a limiting engagement with the locking assembly. The jump fastener moves towards the side closer to the locking assembly under the drive of the handle drive assembly, and forms the locking engagement with the locking assembly through the locking groove. At this time, the jump fastener is in the first position and cooperates with the locking assembly to transmit the opening or closing movement of the operating mechanism. When the operating mechanism disengages, the jumping fastener and the locking assembly release the locking engagement, causing the jumping fastener to move away from the locking assembly under the drive of the mechanism spring, and forming the limiting engagement with the locking assembly through the limiting structure. At this time, the jumping fastener is in the second position and maintains a preset gap with the mechanism push rod.

[0007] As a preferred embodiment, the two side plates of the mechanism frame are provided with arc-shaped grooves facing each other. The two ends of the mechanism push rod are slidably connected to the arc-shaped grooves through the handle lever. The top of the jump fastener is provided with a pressure-receiving part that cooperates with the mechanism push rod. The pressure-receiving part has a V-shaped structure. When the operating mechanism is disengaged, the mechanism push rod returns to one end of the arc-shaped groove and maintains the preset gap with the pressure-receiving part. When the operating mechanism is re-engaged, the handle lever drives the mechanism push rod to move to the other end of the arc-shaped groove, so that the mechanism push rod presses against the pressure-receiving part.

[0008] As a preferred embodiment, the pressure-bearing part is a V-shaped pressure-bearing groove formed on the top of the jump fastener. The V-shaped pressure-bearing groove includes a relief slope and a pressure slope set at a preset angle. The pressure slope extends to the top of one end of the jump fastener. When the mechanism push rod moves along the arc-shaped groove and presses against the pressure slope, it drives the jump fastener to rotate towards the side closer to the locking assembly. When the jump fastener is in the second position, the mechanism push rod is located above the relief slope and does not contact the top of the jump fastener.

[0009] As a preferred embodiment, the jump fastener has a first end and a second end facing away from each other. The first end is rotatably mounted on the mechanism frame via a jump fastener shaft, and the second end of the jump fastener is provided with the locking groove. The limiting structure is a limiting hook formed on the second end of the jump fastener. The limiting hook is located below the locking groove, and the movement trajectory of the limiting hook intersects with the movement trajectory of the locking assembly. When the jump fastener and the locking assembly disengage and rotate relative to each other, the limiting hook abuts against the locking assembly to limit the rebound stroke of the jump fastener.

[0010] As a preferred embodiment, the second end of the jump fastener is connected to the limiting hook in an L-shaped structure; the limiting hook includes a main body section and a hook section, the main body section is formed by protruding outward from the bottom of the second end of the jump fastener, the hook section is formed by extending from the end of the main body section along the length direction of the jump fastener, and one side of the main body section is a guide arc edge connecting the hook section and the locking groove.

[0011] As a preferred embodiment, the locking groove is a U-shaped slot formed at the second end of the trip buckle body, and the side wall of the U-shaped slot away from the limiting hook has a guide bevel. The trip buckle assembly also includes a lower connecting rod structure that is movably hinged to the trip buckle. The lower connecting rod structure is drivenly connected to the moving contact mechanism. One end of the mechanism spring is hooked to the handle lever, and the other end is hooked to the lower connecting rod structure to drive the moving contact mechanism to perform opening or closing movements.

[0012] As a preferred embodiment, the locking assembly includes a locking member, a locking shaft, and a release member. The locking member is rotatably mounted on the mechanism frame via the locking shaft, which is parallel to the mechanism push rod. One end of the locking member engages with the locking groove to form a locking engagement with the release member. The release member engages with the locking member or the locking shaft via a limiting hook to form a limiting engagement.

[0013] As a preferred embodiment, a support shaft parallel to the locking shaft is fixedly mounted on the mechanism frame. The release element is rotatably mounted on the support shaft and located on one side of the locking element. The release element is linked to the locking element via a transmission shaft. A locking torsion spring is provided on the locking shaft, and a release torsion spring is provided on the support shaft, connecting the release element. A traction rod is rotatably mounted on the mechanism frame below the release element and the locking element. The traction rod has a release half-groove. The release element has a release arm extending towards the traction rod. When the locking element and the release element form a locking engagement, the release arm engages and abuts against the release half-groove. When the traction rod is driven to rotate, the release half-groove releases its abutment limit on the release arm. The release element rotates under the action of the release torsion spring, causing the locking element to rotate and disengage from the locking groove of the release element to release the locking engagement. Simultaneously, the release element rotates to the second position away from the locking assembly under the drive of the mechanism spring.

[0014] As a preferred embodiment, the operating mechanism is centrally located on the circuit breaker base. A trip unit is installed in the B-phase cavity of the circuit breaker base. The trip unit has a trigger rod inclined towards the traction rod. A push rod is provided on the locking shaft to form a linkage with the locking component. The push rod extends along the movement path of the trigger rod. The locking shaft rotates with the locking assembly and the trip fastener locking engagement, and pushes the trigger rod through the push rod to complete the push-pull-close reset action of the trip unit.

[0015] As a preferred embodiment, the end of the trigger rod is provided with a push-receiving part that cooperates with the booster rod, and a driving part that cooperates with the traction rod. The push-receiving part and the driving part are respectively a first push block and a second push block that extend in opposite directions at the end of the trigger rod. One end of the booster rod extends on the movement path of the first push block, and the traction rod is provided with a release surface that is disposed opposite to the second push block.

[0016] The technical solution of the present invention has the following advantages compared with the prior art: 1. In the high-current molded case circuit breaker operating mechanism provided by the present invention, a locking groove and a limiting structure are simultaneously provided on the trip fastener, and it has a first position and a second position formed in cooperation with the locking assembly. When the operating mechanism trips, the trip fastener moves away from the locking assembly under the drive of the mechanism spring. The limiting structure and the locking assembly form a limiting cooperation to precisely limit the trip fastener to the preset second position, thereby actively controlling the maximum rebound stroke and final stop position of the trip fastener, avoiding excessive rotation, and ensuring that the trip fastener and the mechanism push rod always maintain a preset gap in the second position, avoiding unintended contact between the two. This technology overcomes the problems of unrestrained rebound and uncontrollable movement trajectory of the trip latch in existing technologies. The operating mechanism using this solution not only ensures that the handle drive component is not affected by additional interference forces and can accurately reset after tripping, but also eliminates the sense of obstruction and jamming caused by component interference during re-tripping and closing operations, significantly optimizing the operating feel of high-current circuit breakers. It also avoids abnormal wear caused by frequent collisions and friction of core moving parts such as trip latches, mechanism push rods, and locking components, extending the service life of the operating mechanism and improving the reliability and stability of high-current molded case circuit breakers in long-term operation.

[0017] 2. In the high-current molded case circuit breaker operating mechanism provided by the present invention, when the operating mechanism is in the tripped state, it drives the mechanism push rod to return to one end of the arc-shaped slide groove, which stops just above the avoidance slope and does not contact the top of the trip fastener. Combined with the rigid limitation of the springback stroke of the trip fastener by the limiting structure, the mechanism push rod and the trip fastener are stably maintained at a preset gap. The avoidance slope provides an additional space avoidance area, which structurally avoids the risk of interference such as rubbing or scratching between the mechanism push rod and the edge of the trip fastener. When the operating mechanism is to be re-operated, the handle lever drives the mechanism push rod to slide to the other end of the arc-shaped slide groove. The mechanism push rod first crosses the avoidance slope without contact, and then smoothly abuts against the pressure slope. This can smoothly convert the linear sliding thrust of the mechanism push rod into the rotational torque of the trip fastener with the optimal lever arm ratio, thereby driving the trip fastener and the locking assembly to complete the re-locking, which greatly improves the transmission efficiency, reduces the operating force, effectively adapts to the high operating force conditions of high-current circuit breakers, and improves the mechanism's action accuracy and operational stability.

[0018] 3. In the high-current molded case circuit breaker operating mechanism provided by the present invention, the limiting structure is a limiting hook formed on the second end of the trip fastener. The limiting hook is located on the lower side of the locking groove, and its movement trajectory intersects with the movement trajectory of the locking assembly. With this structure, when the operating mechanism is tripped, the trip fastener and the locking assembly separate and rotate relative to each other, and the limiting hook then hooks against the locking assembly to form a limiting engagement. The hook engagement between the limiting hook and the locking assembly forcibly limits the rebound stroke of the trip fastener, so that the trip fastener stays stably in the second position, effectively solving the problem of excessive rebound of the trip fastener after tripping, which interferes with the handle assembly.

[0019] 4. In the high-current molded case circuit breaker operating mechanism provided by this invention, the locking assembly adopts a separate linkage design of the locking element and the tripping element. The locking element undertakes the dual functions of locking with the tripping element and limiting with the limiting hook. The tripping element is triggered by the traction rod. When the traction rod trips, it triggers the tripping element to rotate around the support shaft, and the locking element pivots synchronously around the locking shaft, causing the locking element to disengage from the locking groove of the tripping element and unlock. At this time, the tripping element rotates rapidly away from the locking assembly under the action of the mechanism spring, and forms a limiting engagement with the locking element or the locking shaft through the limiting hook, thereby forcibly constraining the rebound stroke of the tripping element and further improving the anti-interference effect. The tripping response of this locking assembly in cooperation with the traction rod and the tripping element is timely and the action transmission is sensitive, ensuring the speed and reliability of circuit breaker fault tripping.

[0020] 5. In the high-current molded case circuit breaker operating mechanism provided by this invention, during the re-clamping process, the locking element and the tripping element form a locking engagement, causing the locking shaft to rotate synchronously with the locking element and drive the push rod to push against the trigger rod, thus completing the push-pull engagement and reset of the trip unit through mechanical linkage. The advantages of this design are: firstly, it integrates the two actions of re-clamping the operating mechanism and the trip unit engagement and reset into the same operation process, allowing the user to complete the trip unit reset synchronously without additional steps, preparing for the next fault trip, greatly improving ease of use and enhancing the safety and reliability of the circuit breaker; secondly, the push rod directly utilizes the existing rotation of the locking shaft, eliminating the need for an additional independent drive component, significantly simplifying the mechanism structure, resulting in high transmission efficiency and meeting the requirements of high-current circuit breakers for trip unit reset force.

[0021] 6. In the high-current molded case circuit breaker operating mechanism provided by the present invention, by providing a first push block and a second push block extending in opposite directions at the end of the trigger rod, the independent functions of reset force and tripping force are realized. The first push block is responsible for bearing the pushing force of the booster rod to complete the pull-in reset action of the trip unit; the second push block is responsible for driving the traction rod to realize the tripping trigger of the circuit breaker in the fault state. This structure, through the design of the first push block and the second push block with opposite inclination and different stroke, and matching the respective movement trajectories of the booster rod and the traction rod, realizes the timing separation and non-interference of the reset drive and tripping drive of the trip unit. Attached Figure Description

[0022] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the accompanying drawings used in the description of the specific embodiments or the prior art will be briefly introduced below.

[0023] Figure 1 This is a schematic diagram of the installation structure of the high-current molded case circuit breaker operating mechanism of the present invention. Figure 2 This is a schematic diagram of the high-current molded case circuit breaker operating mechanism of the present invention from another direction; Figure 3 for Figure 1 The diagram shows a cross-sectional view of the operating mechanism of a high-current molded case circuit breaker. Figure 4 This is a three-dimensional structural schematic diagram of the operating mechanism of the high-current molded case circuit breaker of the present invention; Figure 5 This is a schematic diagram of the planar structure of the high-current molded case circuit breaker operating mechanism of the present invention; Figure 6 This is a schematic diagram of the structure of the jump fastener of the present invention; Figure 7 This is a schematic diagram of the trip unit of the present invention.

[0024] Explanation of reference numerals in the attached drawings: 1. Mechanism frame; 11. Arc-shaped slide groove; 2. Handle drive assembly; 21. Handle lever; 22. Mechanism push rod; 3. Tripping buckle assembly; 31. Tripping buckle element; 32. Locking groove; 33. Limiting structure; 34. Pressure-bearing part; 341. Avoidance slope; 342. Pressure-bearing slope; 35. Tripping buckle shaft; 36. Lower connecting rod structure; 4. Mechanism spring; 5. Locking buckle assembly; 51. Locking buckle element; 52. Locking buckle shaft; 53. Tripping element; 54. Support shaft; 55. Transmission shaft; 56. Locking torsion spring; 57. Tripping torsion spring; 58. Tripping arm; 6. Push rod; 7. Traction rod; 71. Tripping surface; 72. Tripping half groove; 8. Tripping device; 81. Trigger rod; 82. First push block; 83. Second push block; 9. Circuit breaker base; 10. Moving contact mechanism. Detailed Implementation

[0025] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0026] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0027] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0028] Example This embodiment provides, as follows: Figures 1-7 The operating mechanism of a high-current molded case circuit breaker shown includes a frame 1 and a latching assembly 5, a tripping assembly 3, a handle driving assembly 2, and a mechanism spring 4 disposed on the frame 1. The tripping assembly 3 includes a tripping member 31 rotatably disposed on the frame 1, which has a locking groove 32 and a limiting structure 33. The mechanism spring 4 connects the tripping assembly and the handle driving assembly 2. During the opening and closing process, the operating mechanism accumulates elastic potential energy by stretching or compressing the mechanism spring 4, thereby providing driving force for the opening and closing of the circuit breaker. The handle driving assembly 2 includes a handle that is linked to the circuit breaker. A lever 21 and a mechanism push rod 22 are provided. The lever 21 is reciprocatingly mounted on the mechanism frame 1, and the mechanism push rod 22 is connected to the top of the jump fastener 31. The locking assembly 5 is rotatably mounted on the mechanism frame 1 and connected between the jump fastener 31 and the traction rod 7. The jump fastener 31 has a first position that forms a locking engagement with the locking assembly 5, and a second position that forms a limiting engagement with the locking assembly 5. A mechanism spring 4 continuously acts on the jump fastener assembly and the locking assembly 5 to maintain their locked state. The switching between the first and second positions of the jump fastener 31 is described below: The jump fastener 31 moves toward the side closer to the locking assembly 5 under the drive of the handle drive assembly 2, and forms the locking engagement with the locking assembly 5 through the locking groove 32. At this time, the jump fastener 31 is in the first position and cooperates with the locking assembly 5 to transmit the opening or closing movement of the operating mechanism, that is, the operating mechanism can perform normal opening and closing operations. When the operating mechanism disengages, the jumping fastener 31 and the locking assembly 5 release the locking engagement, causing the jumping fastener 31 to move away from the locking assembly 5 under the drive of the mechanism spring 4, and forming the limiting engagement with the locking assembly 5 through the limiting structure 33. At this time, the jumping fastener 31 is in the second position and maintains a preset gap with the mechanism push rod 22.

[0029] In the above embodiment, by simultaneously providing a locking groove 32 and a limiting structure 33 on the jump fastener 31, and having a first position and a second position formed in cooperation with the locking assembly 5, when the operating mechanism disengages, the jump fastener 31 moves away from the locking assembly under the drive of the mechanism spring. The limiting structure 33 and the locking assembly 5 form a limiting cooperation, precisely restricting the jump fastener 31 to the preset second position. This actively controls the maximum rebound stroke and final stop position of the jump fastener 31, avoiding excessive rotation, and ensuring that the jump fastener 31 maintains a preset gap with the mechanism push rod 22 in the second position, preventing the possibility of unintended contact between the two. Overcoming the problems of unrestrained rebound and uncontrollable movement trajectory of existing technologies, the operating mechanism of this technical solution not only ensures that the handle drive component is not affected by additional interference forces and can accurately reset after tripping, making the circuit breaker tripping and tripping status indications clear and accurate, but also eliminates the sense of obstruction and jamming caused by component interference during re-tripping and closing operations, significantly optimizing the operating feel of high-current circuit breakers. Furthermore, it avoids abnormal wear caused by frequent collisions and friction of core moving parts such as tripping contacts, mechanism push rods, and locking components, extending the service life of the operating mechanism and improving the long-term reliability and stability of high-current molded case circuit breakers.

[0030] The following is combined Figures 2-6 A detailed explanation of the specific structure of the jump-lock assembly and the handle drive assembly is provided below: The two side plates of the mechanism frame 1 are provided with arc-shaped sliding grooves 11 facing each other. The two ends of the mechanism push rod 22 pass through the handle lever 21 and are slidably connected in the arc-shaped sliding grooves 11. The top of the trip fastener 31 is provided with a pressure-bearing part 34 that cooperates with the mechanism push rod 22. The pressure-bearing part 34 has a V-shaped structure. When the operating mechanism trips, the mechanism push rod 22 returns to one end of the arc-shaped sliding groove 11 and maintains the preset gap with the pressure-bearing part 34, ensuring that the trip fastener 31 does not interfere with the mechanism push rod 22 in the second position. In the high-current molded case circuit breaker, when the circuit breaker trips due to circuit overload, short circuit or other faults, the locking cooperation between the locking assembly 5 and the trip fastener 31 is released, and the operating mechanism is in the tripped state and cannot be directly... To perform the closing operation, the handle drive assembly 2 drives the jump fastener 31 to move towards the side closer to the locking assembly 5, so that the two re-establish a stable locking engagement. This process is the re-locking process of the operating mechanism. When the operating mechanism re-locks, the handle lever 21 drives the mechanism push rod 22 to move towards the other end of the arc-shaped slide groove 11, so that the mechanism push rod 22 gradually presses against the V-shaped pressure part 34. By pressing against the V-shaped pressure part 34, the sliding thrust of the mechanism push rod 22 can be smoothly converted into the rotational torque of the jump fastener 31, thereby driving the jump fastener 31 to pivot to the first position in a smooth and controllable manner and completing the locking engagement with the locking assembly. This effectively eliminates the sense of resistance and impact vibration during the re-locking process, and improves the transmission efficiency and operating feel.

[0031] As a preferred embodiment, refer to Figure 6The pressure-bearing part 34 is a V-shaped pressure-bearing groove formed on the top of the jump fastener 31. The V-shaped pressure-bearing groove includes a relief slope 341 and a pressure slope 342 set at a preset angle. The pressure slope 342 extends to the top of one end of the jump fastener. With this structure, when the operating mechanism is in the disengaged state, the handle lever 21 drives the mechanism push rod 22 to return to one end of the arc-shaped slide groove 11, which stops just above the relief slope 341 and does not contact the top of the jump fastener 31. Combined with the rigid limitation of the rebound stroke of the jump fastener 31 by the limiting structure 33, the jump fastener 31 is limited to the second position, so that the mechanism push rod 22 and the jump fastener 31 maintain a stable preset gap. The relief slope 341 provides an additional space relief area, which undertakes the structural clearance function between the mechanism push rod 22 and the jump fastener 31 in the disengaged state. Structurally, it avoids the mechanism push rod 22 and the top edge of the jump fastener 31 from rubbing or scratching. To mitigate the risk of interference, when the operating mechanism re-engages, the handle lever 21 drives the mechanism push rod 22 to slide along the arc-shaped groove. The mechanism push rod 22 first passes over the avoidance slope 341 without contact, and then smoothly abuts against the pressure slope 342. The pressure slope 342 undertakes the force transmission function during the re-engagement process of the mechanism, and can form a precise stroke match with the sliding stroke of the mechanism push rod 22 along the arc-shaped groove 11. It can smoothly convert the sliding thrust of the mechanism push rod 22 into the rotational torque of the jump fastener 31 with the optimal lever arm ratio, thereby driving the jump fastener 31 to rotate towards the side closer to the locking assembly 5, realizing the re-locking of the jump fastener 31 and the locking assembly 5, greatly improving the transmission efficiency and reducing the operating force. The jump fastener, through the design of the pressure part structure of the partitioned slope, simultaneously achieves the two major functions of safe avoidance of tripping and smooth drive of re-engagement, effectively adapting to the high operating force conditions of high current circuit breakers, and improving the mechanism's action accuracy and operational stability.

[0032] like Figure 3As shown, the jump fastener 31 has a first end and a second end facing away from each other. The first end is rotatably mounted on the frame 1 via a jump fastener shaft 35. The second end of the jump fastener 31 is provided with the locking groove 32. The limiting structure is a limiting hook formed on the second end of the jump fastener 31. The limiting hook is located below the locking groove 32. The second end of the jump fastener 31 is connected to the limiting hook in an L-shaped outline. Specifically, the limiting hook includes a main body section and a hook section. The main body section protrudes outward from the bottom of the second end of the jump fastener 31. The hook section extends from the end of the main body section along the length direction of the jump fastener 31. One side of the main body section is a guide arc edge connecting the hook section and the locking groove 32. The guide arc edge plays a smooth guiding role during the rebound limiting process of the jump fastener 31, eliminating jamming and hard impact, making the limiting action smoother. This design improves the connection strength and structural integrity between the limiting hook and the jump fastener body. With this structural setting, based on the intersection of the movement trajectory of the limiting hook and the movement trajectory of the locking assembly 5, when the operating mechanism is disengaged, the jump fastener 31 and the locking assembly 5 are disengaged and rotate relative to each other, and the limiting hook then hooks against the locking assembly 5 to form a limiting engagement. The hook engagement between the limiting hook and the locking assembly 5 forcibly limits the rebound stroke of the jump fastener 31, so that the jump fastener stays stably in the second position, effectively solving the problem of excessive rebound of the jump fastener after disengagement and interference with the handle drive assembly.

[0033] In a further preferred configuration, the trip buckle assembly also includes a lower connecting rod structure 36 that is movably hinged to the trip buckle 31. The lower connecting rod structure 36 is connected to the moving contact mechanism 10. One end of the mechanism spring 4 is hooked to the handle lever 21, and the other end is hooked to the lower connecting rod structure 36 to drive the moving contact mechanism 10 to perform opening or closing movements. The handle lever 21 drives the trip buckle 31 through the mechanism push rod 22. The trip buckle 31 drives the lower connecting rod structure 36 that is hinged to it to move. When the mechanism spring 4 passes the dead point position, it releases the stored energy and pulls the lower connecting rod structure 36 to move quickly. The lower connecting rod structure drives the moving contact mechanism 10 to complete the closing action. Similarly, the opening action of the contact mechanism can also be realized.

[0034] The following is combined Figures 3-5 A detailed explanation of the specific structure of the locking assembly is provided below: The locking assembly 5 includes a locking member 51, a locking shaft 52, and a release member 53. The locking member 51 is rotatably mounted on the mechanism frame 1 via the locking shaft 52, which is parallel to the mechanism push rod 22. One end of the locking member 51 engages with the locking groove 32 to form a locking engagement with the jump fastener 31. The jump fastener 31 engages with the locking member 51 or the locking shaft 52 via a limiting hook to form a limiting engagement. Based on the existing mechanism, it is preferred to design that the limiting hook engages with the locking shaft after the jump fastener rotates. The locking groove 32 is a U-shaped groove opened at the second end of the jump fastener body. The side wall of the U-shaped groove away from the limiting hook has a guide bevel. The guide bevel smoothly guides the end of the locking member 51 into the U-shaped groove, avoiding hard collisions and jamming, and improving the smoothness and reliability of the locking engagement. In a further preferred configuration, a support shaft 54 ​​parallel to the locking shaft 52 is fixedly mounted on the mechanism frame 1. The release member 53 is rotatably mounted on the support shaft 54 ​​and located on one side of the locking member 51. The release member 53 is linked to the locking member 51 via a transmission shaft 55. A locking torsion spring 56 is provided on the locking shaft 52, and a release torsion spring 57 is provided on the support shaft 54, connecting the release member. A rotatable support shaft 54 ​​located below the release member 53 and the locking member 51 is rotatably mounted on the mechanism frame 1. The traction rod 7 has a release half-groove 72. The release member 53 has a release arm 58 extending toward one side of the traction rod 7. When the locking member 51 and the jump member 31 form a locking engagement, the release arm 58 engages and abuts in the release half-groove 72. At this time, the release arm 58 of the release member 53 is limited and fixed by the release half-groove 72 of the traction rod 7, so that the release member 53 cannot rotate, and the locking member 51 is kept in the locking groove 32 of the jump member 31 under the action of the locking torsion spring 56, so that the mechanism is in a stable locked state. Therefore, when the circuit breaker detects a circuit fault, the trip unit 8 triggers the traction rod 7 to trip and rotate. The trip half-groove 72 releases its contact limit on the trip arm 58. The trip member 53 rotates under the action of the trip torsion spring 57, and drives the locking member 51 to rotate and disengage from the locking groove of the jump member 31 to release the locking engagement. At the same time, the jump member 31 rotates to a second position away from the locking assembly 5 under the drive of the mechanism spring 4, and the limiting hook completes the limiting action on the jump member 31, realizing the rapid tripping and opening of the operating mechanism.

[0035] As can be seen from the above structure, the locking assembly 5 in this embodiment adopts a separate linkage design of locking element 51 and release element 53. The locking element 51 uses the locking shaft 52 as the rotation fulcrum, resulting in stronger overall motion coordination. The locking element 51 performs the dual functions of locking with the jumper 31 and limiting the movement of the limit hook. This effectively disperses the impact load under high current conditions, improving the structural strength and operational reliability of the locking assembly 5. The release element 53 is triggered by the interaction with the traction rod 7, i.e., the traction rod 7 rotates during release. When activated, the tripping component 53 rotates around the support shaft 54, and the locking component 51 pivots synchronously around the locking shaft 52, causing the locking component 51 to disengage from the locking groove 32 of the tripping component 31 to unlock. The limiting hook engages with the locking component 51 or the locking shaft 52 to form a limiting engagement, thereby forcibly constraining the rebound stroke of the tripping component and limiting it to the second position, further improving the anti-interference effect. The tripping response of this locking component 5 in conjunction with the traction rod 7 and the tripping component 31 is timely and the action transmission is sensitive, ensuring the speed and reliability of the circuit breaker fault tripping.

[0036] In this embodiment, combined with Figures 1-3 As shown, the operating mechanism is centrally located on the circuit breaker base 9. A trip unit 8 is installed in the B-phase cavity of the circuit breaker base 9. The trip unit 8 is provided with a trigger rod 81 inclined towards the traction rod 7. A push rod 6 is provided on the locking shaft 52 to form a linkage with the locking component 51. The push rod 6 extends on the movement path of the trigger rod 81. When the operating mechanism re-locks, the locking shaft 52 rotates with the locking component 5 and the jump fastener 31 during the locking process of the locking component 51 and the jump fastener 31. The push rod 6 pushes the trigger rod 81 to complete the push-pull-close reset action of the trip unit 8. The advantages of this design are twofold: First, it integrates the two actions of the operating mechanism re-clamping and the trip unit 8 engaging and resetting into the same operation process. Users can complete the reset of the trip unit 8 simultaneously without additional steps, preparing for the next fault trip, greatly improving ease of use, avoiding the failure of the protection function due to the trip unit 8 not resetting, and improving the safety and reliability of the circuit breaker. Second, the push rod 6 directly utilizes the existing rotation of the locking shaft 52, without the need to add an independent drive component, greatly simplifying the mechanism structure. The force transmission path is short and the efficiency is high, which can meet the requirements of high current circuit breakers for the reset force of the trip unit.

[0037] In this embodiment, the trip unit 8 adopts a push-pull engagement structure, which includes an iron core assembly, an electromagnetic coil, a permanent magnet, and a trigger rod 81. The iron core assembly consists of a moving iron core and a spring. The iron core assembly and the trigger rod are linked. The push-reset process of this trip unit 8 is as follows: During the re-engaging process of the mechanism, the locking shaft 52 drives the push rod 6 to rotate at a small angle. The push rod 6 pushes against the trigger rod 81 to achieve a short stroke movement, which drives the iron core assembly to overcome the spring force and move towards the permanent magnet side. The moving iron core is actively attracted into place under the magnetic attraction of the permanent magnet, completing the reset engagement of the trip unit. This process only requires a small angle rotation of the push rod and a short stroke movement of the trigger rod. When the circuit breaker detects a short circuit, overload, or other fault, the electromagnetic coil of the trip unit 8 is energized to generate a reverse magnetic flux, which cancels the magnetic attraction force of the permanent magnet. The spring releases energy instantaneously and pushes the moving iron core and the trigger rod to quickly extend and act on the traction rod, thereby triggering the tripping of the operating mechanism.

[0038] like Figure 7 As shown, the trigger rod 81 has a push-receiving part that cooperates with the push rod 6, and a driving part that cooperates with the traction rod 7. The push-receiving part and the driving part are respectively a first push block 82 and a second push block 83 that extend in opposite directions at the end of the trigger rod 81. The extension length of the second push block 83 is greater than the extension length of the first push block 82. One end of the push rod 6 extends on the movement path of the first push block 82, which can smoothly convert the thrust of the push rod 6 into the displacement force of the iron core assembly toward the permanent magnet, ensuring reliable engagement between the iron core assembly and the permanent magnet. The traction rod 7 has a tripping surface 71 that is opposite to the second push block 83. When the trip unit 8 is triggered to trip, the trigger rod 81 is driven to pop out toward the traction rod 7, which drives the second push block 83 to act on the tripping surface 71 of the traction rod 7, thereby driving the traction rod 7 to trip and rotate. This design ensures both reliable engagement and reset of the trip unit 8 and smooth fault tripping response. The advantage of this structural design is that the trigger rod 81 achieves independent functions of boosting force and tripping force through the first push block 82 and the second push block 83. The first push block 82 is responsible for bearing the pushing force of the booster rod 6. The short stroke structure of the first push block 82 is precisely adapted to the small displacement required for permanent magnet attraction, with no extra idle stroke, ensuring the completion of the attraction and reset action of the trip unit 8. The second push block 83 is responsible for driving the traction rod 7. The long inclined structure of the second push block 83 can provide sufficient driving stroke and force arm, and can drive the traction rod to quickly trip when the trip unit 8 is triggered, so as to realize the rapid tripping triggering of the circuit breaker in the fault state.

[0039] This structure, through the design of the first push block 82 and the second push block 83 with reverse tilt and differentiated stroke, and matching the respective movement trajectories of the push rod 6 and the traction rod 7, achieves the timing separation and non-interference of the reset drive between the trip unit 8 and the push rod 6 and the trip drive between the trip unit 8 and the traction rod 7. This is based on the fact that when the circuit breaker is in the tripped state, the traction rod 7 is driven by the trigger rod 81 of the trip unit 8 to be in the tripped position. The trip unit 8 completes the pull-in reset action during the re-clamping process of the operating mechanism. Specifically, the push rod 6 makes a small angle rotation to drive the trigger rod 81 and the moving iron core to move closer to the permanent magnet side, so that when the moving iron core is attracted into place by the permanent magnet, the push-in reset of the trip unit 8 is completed, and a clearance gap is formed between the push rod 6 and the trigger rod 81. At the same time, the traction rod 7 is synchronously reset under the action of its own reset spring, and the second push block, which is closer to the trigger rod, has a relatively long tilt length. Therefore, when the trip unit 8 is triggered again due to a circuit failure, the trigger rod 81 pops outward and will act on the already reset traction rod 7 first through the second push block. It will not come into contact with or interfere with the push rod 6 which is in the avoidance position. This forms a clear action sequence in which the traction rod is triggered first and the push rod is not acted on when the trip is triggered, ensuring that the tripping and reset actions do not interfere with each other and that the mechanism operates stably and reliably.

[0040] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. An operating mechanism for a high-current molded case circuit breaker, comprising a mechanism frame (1) and a locking assembly (5), a tripping assembly (3), a handle driving assembly (2), and a mechanism spring (4) disposed on the mechanism frame (1), characterized in that: The jump buckle assembly (3) includes a jump buckle (31) rotatably mounted on the mechanism frame (1). The jump buckle (31) is provided with a locking groove (32) and a limiting structure (33). The mechanism spring (4) is connected between the jump buckle assembly and the handle drive assembly (2). The handle drive assembly (2) includes a handle lever (21) and a mechanism push rod (22) that are linked together. The handle lever (21) is reciprocated and oscillates on the mechanism frame (1). The mechanism push rod (22) is connected to the top of the jump fastener (31) in a transmission connection. The locking assembly (5) is rotatably connected between the jump fastener (31) and the traction rod (7); the jump fastener (31) rotates towards the side closer to the locking assembly (5) under the drive of the handle drive assembly (2), and forms a locking engagement with the locking assembly (5) through the locking groove (32); the jump fastener (31) has a first position that forms a locking engagement with the locking assembly (5), and a second position that forms a limiting engagement with the locking assembly (5); When the operating mechanism disengages, the jumping fastener (31) and the locking assembly (5) release the locking engagement, causing the jumping fastener (31) to move away from the locking assembly (5) under the drive of the mechanism spring (4), and forming the limiting engagement with the locking assembly (5) through the limiting structure (33). At this time, the jumping fastener (31) is in the second position and maintains a preset gap with the mechanism push rod (22).

2. The high current molded case circuit breaker operating mechanism of claim 1, wherein: The two side plates of the mechanism frame (1) are provided with arc-shaped grooves (11) facing each other. The two ends of the mechanism push rod (22) are slidably connected to the arc-shaped groove (11) through the handle lever (21). The top of the jump fastener (31) is provided with a pressure part (34) that cooperates with the mechanism push rod (22). The pressure part (34) has a V-shaped structure. When the operating mechanism is disengaged, the mechanism push rod (22) returns to one end of the arc-shaped groove (11) and maintains the preset gap between it and the pressure part (34). When the operating mechanism is re-engaged, the handle lever (21) drives the mechanism push rod (22) to move to the other end of the arc-shaped groove (11), so that the mechanism push rod (22) presses against the pressure part (34).

3. The operating mechanism of the high-current molded case circuit breaker according to claim 2, characterized in that: The pressure-bearing part (34) is a V-shaped pressure-bearing groove opened on the top of the jump fastener (31). The V-shaped pressure-bearing groove includes a relief slope (341) and a pressure slope (342) set at a preset angle. The pressure slope (342) extends to the top of one end of the jump fastener. When the mechanism push rod (22) moves along the arc-shaped slide (11) and presses against the pressure slope (342), it drives the jump fastener (31) to rotate towards the side closer to the locking assembly (5). When the jump fastener (31) is in the second position, the mechanism push rod (22) is located above the relief slope (341) and does not contact the top of the jump fastener (31).

4. The operating mechanism of the high-current molded case circuit breaker according to claim 1, characterized in that: The jump fastener (31) has a first end and a second end facing away from each other. The first end is rotatably mounted on the frame (1) via a jump fastener shaft (35). The second end of the jump fastener (31) is provided with the locking groove (32). The limiting structure is a limiting hook formed on the second end of the jump fastener (31). The limiting hook is located on the lower side of the locking groove (32). The movement trajectory of the limiting hook intersects with the movement trajectory of the locking assembly (5). When the jump fastener (31) and the locking assembly (5) are disengaged and rotate relative to each other, the limiting hook abuts against the locking assembly (5) to limit the rebound stroke of the jump fastener (31).

5. The operating mechanism of the high-current molded case circuit breaker according to claim 4, characterized in that: The second end of the jump fastener (31) is connected to the limiting hook in an L-shaped structure; the limiting hook includes a main body section and a hook section. The main body section is formed by protruding outward from the bottom of the second end of the jump fastener (31), and the hook section is formed by extending along the length direction of the jump fastener (31) from the end of the main body section. One side of the main body section is a guide arc edge connecting the hook section and the locking groove (32).

6. The operating mechanism of the high-current molded case circuit breaker according to claim 1, characterized in that... The locking groove (32) is a U-shaped slot opened at the second end of the jump buckle body. The side wall of the U-shaped slot away from the limit hook has a guide bevel. The jump buckle assembly also includes a lower connecting rod structure (36) that is movably hinged to the jump buckle (31). The lower connecting rod structure (36) is connected to the moving contact mechanism (10). One end of the mechanism spring (4) is hooked to the handle lever (21), and the other end is hooked to the lower connecting rod structure (36) to drive the moving contact mechanism (10) to perform opening or closing movements.

7. The operating mechanism of the high-current molded case circuit breaker according to any one of claims 1-6, characterized in that... The locking assembly (5) includes a locking member (51), a locking shaft (52), and a release member (53). The locking member (51) is rotatably mounted on the mechanism frame (1) via the locking shaft (52). The locking shaft (52) is parallel to the mechanism push rod (22). One end of the locking member (51) is engaged in the locking groove (32) to form a locking engagement with the jumper member (31). The jumper member (31) is engaged in the locking member (51) or the locking shaft (52) via a limiting hook to form a limiting engagement.

8. The operating mechanism of the high-current molded case circuit breaker according to claim 7, characterized in that: The mechanism frame (1) is fixedly provided with a support shaft (54) parallel to the locking shaft (52). The release member (53) is rotatably mounted on the support shaft (54) and located on one side of the locking member (51). The release member (53) is linked to the locking member (51) through a transmission shaft (55). The locking shaft (52) is provided with a locking torsion spring (56) connecting the locking shaft (52). The support shaft (54) is provided with a locking torsion spring (56) connecting the release member (51). The fastener has a release torsion spring (57); the mechanism frame (1) is rotatably provided with a traction rod (7) located below the release member (53) and the locking member (51), the traction rod (7) is provided with a release half groove (72), the release member (53) is provided with a release arm (58) extending toward the traction rod (7), the release arm (58) engages with the release half groove (72) when the locking member (51) and the jump fastener (31) form a locking engagement.

9. The operating mechanism of the high-current molded case circuit breaker according to claim 7, characterized in that: The operating mechanism is centrally located on the circuit breaker base (9). A trip unit (8) is installed in the B-phase cavity of the circuit breaker base (9). The trip unit (8) is provided with a trigger rod (81) inclined towards the traction rod (7). A push rod (6) is provided on the locking shaft (52) to form a linkage with the locking member (51). The push rod (6) extends on the movement path of the trigger rod (81). The locking shaft (52) rotates with the locking assembly (5) and the jump fastener (31) locking engagement, and pushes the trigger rod (81) through the push rod (6) to complete the push-pull-close reset action of the trip unit (8).

10. The operating mechanism of the high-current molded case circuit breaker according to claim 9, characterized in that: The trigger rod (81) has a push-receiving part that cooperates with the push rod (6) and a drive part that cooperates with the traction rod (7) at its end. The push-receiving part and the drive part are respectively a first push block (82) and a second push block (83) that extend in opposite directions at the end of the trigger rod (81). One end of the push rod (6) extends on the movement path of the first push block (82). The traction rod (7) has a release surface (71) that is opposite to the second push block (83).

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