A thermomagnetic adjustable release device and circuit breaker

Abstract

The application discloses a thermal-magnetic adjustable tripping device and a circuit breaker in the technical field of low-voltage circuit breakers, comprising a thermal tripping assembly and a magnetic tripping assembly, wherein the thermal tripping assembly uses a sliding slider assembly to form a distance change with the slope of a first traction rod, and the magnetic tripping assembly uses a rotating second traction rod to change the deformation amount of a transient spring. The application solves the problem that the thermal tripping time and the magnetic tripping current cannot be adjusted in the prior art by adjusting the thermal tripping time in two ways and the magnetic tripping current in one way, thereby achieving the beneficial effect of improving the convenience of thermal-magnetic tripping adjustment.

Description

Technical Field

[0001] This application relates to the field of low-voltage circuit breaker technology, specifically to a thermomagnetic adjustable trip device and circuit breaker. Background Technology

[0002] The thermal-magnetic trip unit is an important component of circuit breakers, providing magnetic protection against short circuits and thermal protection against overloads. When the circuit is overloaded, the bimetallic strip deforms due to heat, actuating the operating mechanism to disconnect the circuit. When the circuit is short-circuited, the electromagnet of the thermal-magnetic trip unit generates magnetic force to attract the armature, causing the armature to actuate the operating mechanism to disconnect the circuit, thus achieving the effect of power outage protection.

[0003] In practical applications, the required thermal tripping time varies depending on the situation. Existing molded case circuit breakers typically have a fixed thermal tripping time, which cannot be adjusted according to actual conditions. Furthermore, sometimes it is necessary to adjust the magnetic tripping current to achieve functions such as graded protection. The magnetic tripping current of existing molded case circuit breakers is also typically fixed and cannot be adjusted according to actual needs. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this application provides a thermo-magnetic adjustable trip device and circuit breaker to solve the problem that the thermal trip time and magnetic trip current cannot be adjusted in the prior art.

[0005] To achieve the above objectives, this application provides the following technical solution:

[0006] A thermo-magnetic adjustable trip device includes a thermal trip assembly and a magnetic trip assembly. The thermal trip assembly includes a thermally adjustable knob, a push rod, a bimetallic assembly, a slider assembly, a slider bracket, and a first traction rod. The magnetic trip assembly includes a magnetically adjustable knob and a second traction rod. Both the thermally adjustable knob and the magnetically adjustable knob have an eccentric structure at their bottom, perpendicular to the knob's axis, and are mounted on their respective fixed brackets parallel to their rotation axes. The slider bracket is mounted on the bimetallic plate of the bimetallic assembly. The push rod is mounted at the bottom of the thermally adjustable knob, perpendicular to its rotation axis, and can slide along the rod direction under the influence of the eccentric structure at the bottom of the thermally adjustable knob. The slider assembly is mounted on a slider bracket parallel to the push rod and is in contact with the push rod. Under the drive of the push rod, it slides along the rod direction. The slider assembly is provided with a top piece perpendicular to the push rod. The first traction rod is perpendicular to the top piece and is provided with an inclined surface that cooperates with the top piece. When the top piece slides, the distance between the top piece and the inclined surface changes. The second traction rod is mounted on the bottom of the magnetically adjustable knob and is perpendicular to the rotation axis of the magnetically adjustable knob. It can rotate along the axial direction of the second traction rod under the drive of the eccentric structure at the bottom of the magnetically adjustable knob. The second traction rod is also in contact with one end of the instantaneous spring of the bimetallic assembly. When the second traction rod rotates, it changes the deformation of the instantaneous spring.

[0007] Preferably, the instantaneous spring is a parallel double torsion spring, and the second traction rod is perpendicular to the straight arms at both ends of the parallel double torsion spring, and the second traction rod extends vertically out of the first cantilever to contact the straight arms at both ends of the parallel double torsion spring.

[0008] Preferably, each of the first cantilever arms has a slot at the center of its top surface that is also perpendicular to the second traction rod, and the straight arms at both ends of the parallel double torsion spring are fixed in the slot.

[0009] Preferably, the second traction rod extends vertically into a second cantilever at the eccentric structure of the magnetically adjustable knob. The inner surface of the second cantilever contacts the convex surface of the eccentric structure, and the second cantilever causes the second traction rod to rotate around its own axis when the eccentric structure rotates around the axis of the magnetically adjustable knob.

[0010] Preferably, the inclined surface is a continuous surface or a stepped surface.

[0011] Preferably, the push rod extends vertically from the eccentric structure of the thermo-adjustable knob to form a thermo-eccentric slot perpendicular to the axis of the thermo-adjustable knob. The eccentric structure of the thermo-adjustable knob extends into the thermo-eccentric slot, and when the eccentric structure rotates around the axis of the thermo-adjustable knob, the thermo-eccentric slot causes the push rod to slide along the rod direction.

[0012] Preferably, the slider assembly includes a slider, a delay screw, and a nut. The delay screw, as a top member, is perpendicular to the first traction rod and fixed to the top member mounting surface of the slider by the nut. When the delay screw slides along the rod direction of the push rod, it falls within the projection plane of the inclined plane.

[0013] Preferably, the bottom of the slider is provided with a sliding groove that slides on the slider bracket, the push rod is provided with a downward slider slot at each slider assembly, and the slider is also provided with a rod portion perpendicular to the push rod and the rod portion is installed in the slider slot.

[0014] Preferably, the top surface of the thermally adjustable knob and the magnetically adjustable knob is provided with arrow grooves.

[0015] Based on the same inventive concept, this application also discloses a circuit breaker, including a base plate, wherein the base plate is divided by phases using base plate ribs, and includes the aforementioned thermomagnetic adjustable trip device, wherein the fixed brackets are respectively fixed to the top surface of different base plate ribs.

[0016] Compared to existing technologies, this solution offers the following advantages: The circuit breaker utilizes a thermally adjustable knob with an eccentric bottom structure that engages with the thermally eccentric slot of the push rod. Rotating the knob causes the push rod to move the slider left and right, altering the distance between the delay screw and the stepped inclined surface of the traction rod. The engagement of the delay screw and nut adds a second layer of distance adjustment, allowing users to adjust the thermal tripping time as needed. Furthermore, the magnetically adjustable knob's eccentric bottom structure, combined with the second traction rod's cantilever design, allows rotation of the knob to change the angle of the instantaneous spring, thereby altering the magnetic yoke's attraction force on the armature and enabling adjustment of different magnetic tripping currents. This significantly improves the ease of adjusting thermal and magnetic tripping. Attached Figure Description

[0017] Figure 1 This is a three-dimensional structural diagram of an embodiment of the circuit breaker of this application;

[0018] Figure 2 This is an exploded view of an embodiment of the thermal trip assembly of this application;

[0019] Figure 3 This is a three-dimensional structural diagram of an embodiment of the thermal trip assembly of this application without the knob and fixing bracket;

[0020] Figure 4 A three-dimensional structural diagram of an embodiment of the thermal trip assembly of this application, with a knob and a fixing bracket attached;

[0021] Figure 5 This is a three-dimensional structural diagram of an embodiment of the magnetic tripping assembly of this application;

[0022] Among them, 1-first traction rod, 11-inclined surface, 2-slider bracket, 3-slider assembly, 31-slider, 311-slide groove, 32-delay screw, 33-nut, 4-bimetallic assembly, 41-instantaneous spring, 42-bimetallic sheet, 43-armature, 44-magnetic yoke, 45-thermal element, 5a-thermally adjustable knob, 5b-magnetically adjustable knob, 51-eccentric structure, 52-arrow groove, 6-push rod, 61-thermally eccentric groove, 62-slider groove, 7-second traction rod, 71-first cantilever, 72-second cantilever, 9-fixed bracket. Detailed Implementation

[0023] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments.

[0024] This embodiment provides a technical solution: a thermomagnetic adjustable trip device disclosed in this solution includes a thermal trip assembly and a magnetic trip assembly. The thermal trip assembly includes a first traction rod 1, a slider bracket 2, a slider assembly 3, a bimetallic assembly 4, a thermally adjustable knob 5a, a push rod 6, and a fixed bracket 9. The end face of the traction rod 1 is designed with a continuous inclined surface 11, which can also be a stepped inclined surface. The slider bracket 2 is fixed on the bimetallic sheet 42 in the bimetallic assembly 4. In this embodiment, the slider bracket 2 has a groove parallel to the bimetallic sheet 42. The bimetallic sheet 42 contacts the heating element 45 and receives heat from the heating element 45. The top of the bimetallic sheet 42 extends into the groove of the slider bracket 2. A slider assembly 3 is mounted on the frame 2. The slider assembly 3 can slide left and right on the slider bracket 2. The slider assembly 3 includes a slider 31, a delay screw 32, and a nut 33. The delay screw 32 can be adjusted back and forth. The push rod 6 connects to the A / B / C phase slider assembly 3. The thermally adjustable knob 5a is mounted on the fixed bracket 9. The bottom eccentric structure 51 of the thermally adjustable knob 5a cooperates with the thermally eccentric groove 61 of the push rod 6. When the thermally adjustable knob 5a is rotated, the push rod 6 drives the slider assembly 3 to move left and right on the slider bracket 2 through the sliding groove 311 of the slider 31 via the slider groove 62, thereby changing the distance between the delay screw 32 and the inclined surface 11 of the first traction rod 1, so that the user can adjust the thermal tripping time as needed.

[0025] In this embodiment, the delay screw 32 constitutes the top part of the slider assembly 3. The implementation of the slider assembly 3 is not limited to the above method. As long as the distance between the top part and the inclined surface 11 can be adjusted and changed when the top part slides.

[0026] The magnetic tripping assembly includes a second traction rod 7, a magnetically adjustable knob 5b, and a fixed bracket 9. The second traction rod 7 is fixed by the fixed bracket 9. The second traction rod 7 has six identical first cantilever arms 71. Each first cantilever arm 71 has a slot that is also perpendicular to the second traction rod 7. The two ends of the instantaneous spring 41 on the bimetallic assembly 4 are fixed in the slots of the first cantilever arms 71. The magnetically adjustable knob 5b is mounted on the fixed bracket 9. The eccentric structure 51 at the bottom of the magnetically adjustable knob 5b cooperates with the second cantilever arm 72 of the second traction rod 7. Rotating the magnetically adjustable knob 5b causes the eccentric structure 51 at the bottom of the magnetically adjustable knob 5b to cooperate with the second cantilever arm 72 on the second traction rod 7, thereby driving the second traction rod 7 to rotate and changing the angle of the instantaneous spring 41, thereby changing the attraction force of the magnetic yoke 44 on the armature 43, and realizing the adjustment of different magnetic tripping action currents. The instantaneous spring 41 uses a parallel double torsion spring, whose Z-shaped arm is engaged in the spring fixing hole on the U-shaped surface of the U-shaped armature 43. Using a parallel double torsion spring can significantly increase the spring torque.

[0027] In this embodiment, the implementation of the second traction rod 7 is not limited to the above structure. As long as the second traction rod 7 can adjust the deformation of the instantaneous spring 41 when the magnetic adjustable knob 5b is rotated, it is acceptable.

[0028] The top surfaces of the thermally adjustable knob 5a and the magnetically adjustable knob 5b are also provided with arrow grooves 52 to indicate the current position status of the two knobs to the adjuster.

[0029] Based on the same inventive concept, this application also discloses a circuit breaker, including an operating mechanism and a base plate. The base plate is divided into A / B / C phases by base plate ribs and includes the aforementioned thermomagnetic adjustable trip device. The fixed brackets 9 are respectively fixed on the top surfaces of different base plate ribs, and the first traction rod 1 is installed on the operating mechanism.

[0030] In the description of this application, it should be noted that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this application and 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, and therefore should not be construed as a limitation on this application. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0031] The above description is only a preferred embodiment of the present solution, but the scope of protection claimed by the present solution is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in this application, based on the technical solution and inventive concept of this application, should be included within the scope of protection of this application.

Claims

1. A thermomagnetically adjustable trip unit, comprising a thermal trip assembly and a magnetic trip assembly, characterized in that: The thermal release assembly includes a thermally adjustable knob (5a), a push rod (6), a bimetallic assembly (4), a slider assembly (3), a slider bracket (2), and a first traction rod (1). The magnetic release assembly includes a magnetically adjustable knob (5b) and a second traction rod (7). The bottom of both the thermally adjustable knob (5a) and the magnetically adjustable knob (5b) is provided with an eccentric structure (51) perpendicular to the knob axis, and both are mounted on their respective fixed brackets (9) with their rotation axes parallel. The slider bracket (2) is mounted on the bimetallic plate (42) of the bimetallic assembly (4). The push rod (6) is mounted on the bottom of the thermally adjustable knob (5a) and is perpendicular to the rotation axis of the thermally adjustable knob (5a), and can slide along the rod direction under the drive of the eccentric structure (51) at the bottom of the thermally adjustable knob (5a). The slider assembly (3) is mounted on the push rod. The slider bracket (2) parallel to the rod (6) is in contact with the push rod (6) and slides along the direction of the rod under the drive of the push rod (6). The slider assembly (3) is provided with a top piece perpendicular to the push rod (6). The first traction rod (1) is perpendicular to the top piece and is provided with an inclined surface (11) that cooperates with the top piece. When the top piece slides, the distance between the top piece and the inclined surface (11) changes. The second traction rod (7) is installed at the bottom of the magnetic adjustable knob (5b) and is perpendicular to the rotation axis of the magnetic adjustable knob (5b). It can rotate along the axial direction of the second traction rod (7) under the drive of the eccentric structure (51) at the bottom of the magnetic adjustable knob (5b). The second traction rod (7) is also in contact with one end of the instantaneous spring (41) of the bimetallic assembly (4). When the second traction rod (7) rotates, it changes the deformation of the instantaneous spring (41).

2. The thermomagnetic adjustable trip device according to claim 1, characterized in that: The instantaneous spring (41) uses a parallel double torsion spring, and the second traction rod (7) is perpendicular to the straight arms at both ends of the parallel double torsion spring and the second traction rod (7) extends perpendicularly out of the first cantilever (71) and contacts the straight arms at both ends of the parallel double torsion spring.

3. The thermomagnetic adjustable trip device according to claim 2, characterized in that: Each of the first cantilever (71) has a slot at the center of its top surface that is also perpendicular to the second traction rod (7), and the straight arms at both ends of the parallel double torsion spring are fixed in the slot.

4. The thermomagnetic adjustable trip device according to claim 1, characterized in that: The second traction rod (7) extends vertically into a second cantilever (72) at the eccentric structure (51) of the magnetically adjustable knob (5b). The inner surface of the second cantilever (72) contacts the convex surface of the eccentric structure (51), and the second cantilever (72) causes the second traction rod (7) to rotate around its own axis when the eccentric structure (51) rotates around the axis of the magnetically adjustable knob (5b).

5. The thermomagnetic adjustable trip device according to claim 1, characterized in that: The inclined surface (11) is a continuous surface or a stepped surface.

6. The thermomagnetic adjustable trip device according to claim 1, characterized in that: The push rod (6) extends vertically from the eccentric structure (51) of the thermo-adjustable knob (5a) to form a thermo-eccentric slot (61) perpendicular to the axis of the thermo-adjustable knob (5a). The eccentric structure (51) of the thermo-adjustable knob (5a) extends into the thermo-eccentric slot (61), and when the eccentric structure (51) rotates around the axis of the thermo-adjustable knob (5a), the thermo-eccentric slot (61) causes the push rod (6) to slide along the rod direction.

7. The thermomagnetic adjustable trip device according to claim 1, characterized in that: The slider assembly includes a slider (31), a delay screw (32) and a nut (33). The delay screw (32) is fixed to the top mounting surface of the slider (31) by the nut (33) perpendicular to the first traction rod (1). When the delay screw (32) slides along the rod direction of the push rod (6), it falls into the projection plane of the inclined plane (11).

8. The thermomagnetic adjustable trip device according to claim 7, characterized in that: The bottom of the slider (31) is provided with a sliding groove (311) that slides on the slider bracket (2). The push rod (6) is provided with a downward slider slot (62) at each slider assembly (3). The slider (31) is also provided with a rod portion perpendicular to the push rod (6) and the rod portion is installed in the slider slot (62).

9. The thermomagnetic adjustable trip device according to claim 1, characterized in that: Arrow grooves (52) are provided on the top surfaces of the thermally adjustable knob (5a) and the magnetically adjustable knob (5b).

10. A circuit breaker, comprising a base plate, the base plate being separated by phases using base plate ribs, characterized in that: The device includes the thermomagnetic adjustable trip device according to any one of claims 1-9, wherein the fixed bracket (9) is fixed on the top surface of different bottom plate reinforcements respectively.

Images