Molded case circuit breaker instantaneous protection structure

Abstract

The utility model relates to the technical field of instantaneous protection structures of molded case circuit breakers, in particular to an instantaneous protection structure of a molded case circuit breaker, which comprises a connecting plate and a connecting plate, the connecting plate is electrically connected with the end part of the connecting plate, the side wall of the connecting plate is fixedly connected with a bracket, an iron core plate is fixedly connected between the bracket and the connecting plate through a rivet, and the iron core plate is connected with the connecting plate. A bimetallic element is fixedly connected to the side, away from the iron core plate, of the connecting plate, an armature is rotationally connected into the support, a coil is clamped to the side, away from the iron core plate, of the bimetallic element, and the coil is electrically connected with the connecting plate. A coil is installed on a bimetallic element, when current on a connecting plate and a connecting plate is instantaneously increased, current flowing through the coil is increased, a magnetic field generated by the coil is changed, attraction force of the coil to the lower half portion of an armature is increased, the armature is driven to rotate, magnetic attraction driving force of the armature is increased through the coil, and the armature is assisted to rotate to trigger tripping. The phenomenon that tripping is caused by insufficient driving of the armature to rotate in a low-voltage state, and a low-voltage circuit is easily and instantaneously protected is prevented.

Description

Technical Field

[0001] The utility model relates to the field of instantaneous protection structures of plastic case circuit breakers, and specifically to an instantaneous protection structure of a plastic case circuit breaker. Background Technique

[0002] The plastic case circuit breaker is also known as a molded case circuit breaker. All parts are sealed in a plastic shell. Auxiliary contacts, under-voltage release devices, shunt release devices, etc. mostly adopt modularization. An instantaneous protection structure is arranged inside the plastic case circuit breaker. When a short circuit or other unexpected conditions occur, the current in the circuit instantaneously increases and is likely to burn out the circuit. The instantaneous protection structure can timely control the circuit breaker to trip and play a role in protecting the circuit.

[0003] The existing instantaneous protection structure of a plastic case circuit breaker, such as the trip protection mechanism and circuit breaker proposed in the patent application number "CN201920083248.7", through structures such as an armature, a pivoting side plate, a pivoting rod, and an isolating sleeve, the isolating sleeve can not only play a role in limiting the pivoting rod, but also can play a role in isolating between the armature and the ear. The trip protection unit can limit the isolating sleeve when it is installed on the housing.

[0004] However, the existing technology has defects. When the circuit where the circuit breaker is located is a low-voltage circuit and the current flowing in the circuit breaker is small, even if the current instantaneously increases due to short circuit or other conditions in the circuit, it is not enough to drive the armature to rotate and cause tripping, and it is not easy to protect the low-voltage circuit in time. Therefore, an instantaneous protection structure of a plastic case circuit breaker is proposed. Content of the Utility Model

[0005] The purpose of the utility model is to provide an instantaneous protection structure of a plastic case circuit breaker to solve the problems proposed in the above background technique.

[0006] The purpose of the utility model can be realized by the following technical solutions:

[0007] An instantaneous protection structure of a plastic case circuit breaker includes a connection plate and a connection board. The ends of the connection plate and the connection board are electrically connected. A bracket is fixedly connected to the side wall of the connection board. An iron core plate is fixedly connected between the bracket and the connection board through a rivet. A bimetallic element is fixedly connected to the side of the connection board away from the iron core plate. An armature is rotatably connected inside the bracket. A coil is clamped to the side of the bimetallic element away from the iron core. The coil is electrically connected to the connection board. The coil is magnetically driven and matched with one end of the armature. A connection end is fixedly connected to the upper end of the armature. A spring is clamped between the end of the connection end and the upper end of the iron core plate.

[0008] Preferably, a fixing ring is fixedly connected to the lower end of the side of the bimetallic element away from the iron core plate through a screw. The screw is threadedly connected to the bimetallic element and the connection board. The coil is clamped on the fixing ring.

[0009] Preferably, a conductive plate is clamped at the lower end of the connecting plate. A conductive member is fixedly connected to the lower end of the conductive plate. Both ends of the coil are electrically connected to the conductive member. Clamping plates are fixedly connected to both sides of the conductive plate, and the two clamping plates are respectively clamped and installed on both sides of the connecting plate.

[0010] Preferably, two connecting ports are provided on one side of the upper end of the bracket. Rotating blocks are fixedly connected to the middle parts of both sides of the armature, and the two rotating blocks are respectively rotatably connected in the two connecting ports.

[0011] Preferably, limiting blocks are fixedly connected to both sides of the lower end of the armature. Limiting grooves are provided on both sides of the lower end of the bracket. The two limiting blocks are respectively located inside the two limiting grooves, and the two limiting blocks are respectively in clamping fit with the inner walls of the two limiting grooves.

[0012] Preferably, a through port is provided on the side wall of the connecting plate. A heat conducting block is fixedly connected to the side of the bimetallic element close to the iron core. The heat conducting block is inserted into the through port, and heat is transferred between the side wall of the heat conducting block and the inner wall of the through port through an insulating sleeve.

[0013] Advantages of the present utility model:

[0014] In the present utility model, by installing a coil on the bimetallic element, when the current on the connecting plate and the connecting plate instantaneously increases, the current flowing through the coil increases, the magnetic field generated by the coil changes, the attractive force of the coil on the lower half of the armature increases, driving the armature to rotate. By increasing the magnetic attraction driving force of the armature through the coil, it assists the armature to rotate and trigger tripping, preventing tripping caused by insufficient driving force of the armature under low voltage conditions, and easily providing instantaneous protection for low voltage circuits. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present utility model or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, for those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings;

[0016] Figure 1 is a schematic diagram of the overall structure of the present utility model;

[0017] Figure 2 is a schematic diagram of the overall side structure of the present utility model;

[0018] Figure 3 is a schematic diagram of the overall sectional structure of the present utility model;

[0019] Figure 4 is a schematic diagram of the bimetallic element structure of the present utility model;

[0020] Figure 5 is a schematic diagram of the coil installation structure of the present utility model;

[0021] The reference numerals in the figures are as follows:

[0022] 1. Connection plate; 2. Connecting plate; 3. Bracket; 4. Iron core plate; 5. Rivet; 6. Bimetallic element; 7. Fixed ring; 8. Screw; 9. Coil; 10. Conductive part; 11. Clamping plate; 12. Conductive plate; 14. Armature; 15. Limit groove; 16. Limit block; 17. Connection port; 18. Rotating block; 21. Connection end; 22. Spring; 23. Through port; 24. Heat conducting block; 25. Insulating sleeve. Detailed implementation manners

[0023] The technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without creative efforts shall fall within the protection scope of the present utility model.

[0024] An instantaneous protection structure for a molded case circuit breaker, as Figures 1-5 shown, includes a connection plate 1 and a connecting plate 2. The ends of the connection plate 1 and the connecting plate 2 are electrically connected. A bracket 3 is fixedly connected to the side wall of the connecting plate 2. An iron core plate 4 is fixedly connected between the bracket 3 and the connecting plate 2 through a rivet 5. A bimetallic element 6 is fixedly connected to the side of the connecting plate 2 away from the iron core plate 4. An armature 14 is rotatably connected inside the bracket 3. A coil 9 is clamped to the side of the bimetallic element 6 away from the iron core. The coil 9 is electrically connected to the connecting plate 2. The coil 9 is magnetically driven and cooperated with one end of the armature 14. A connection end 21 is fixedly connected to the upper end of the armature 14. A spring 22 is clamped between the end of the connection end 21 and the upper end of the iron core plate 4.

[0025] Both the connecting plate 2 and the iron core plate 4 are installed in the bracket 3 through rivets 5. The surface of the bracket 3 is insulated. Electricity is applied to the connecting plate 2 and the connection plate 1. The bimetallic element 6 gets hot when electrified. When the instantaneous current inside the molded case circuit breaker increases, the temperature of the bimetallic element 6 rises and bends to trip. A coil 9 is installed on the bimetallic element 6. When the current on the connection plate 1 and the connecting plate 2 instantaneously increases, the current flowing through the coil 9 increases, the magnetic field generated by the coil 9 changes, the attraction of the coil 9 to the lower half of the armature 14 increases, driving the armature 14 to rotate. The rotation of the armature 14 drives the circuit breaker to trip. When the current returns to normal, the attraction of the coil 9 to the lower half of the armature 14 returns to normal. The spring 22 pulls the armature 14 to reset through the connection end 21, and the instantaneous protection structure returns to its state. By increasing the magnetic attraction driving force of the armature 14 through the coil 9, it assists the rotation of the armature 14 to cause tripping, preventing insufficient driving force to rotate the armature 14 under low voltage conditions to cause tripping, and facilitating the instantaneous protection of low voltage circuits.

[0026] As Figure 2 、 Figure 3 andFigure 5 As shown, at the lower end of the side of the bimetallic element 6 away from the iron core plate 4, a fixing ring 7 is fixedly connected by a screw 8. The screw 8 is threadedly connected to the bimetallic element 6 and the connecting plate 2, and the coil 9 is clamped on the fixing ring 7.

[0027] The fixing ring 7 and the screw 8 mount the coil 9 on one side of the bimetallic element 6, facilitating the fixing of the coil 9.

[0028] As Figures 1-3 、 Figure 5 shown, a conductive plate 12 is clamped at the lower end of the connecting plate 2. A conductive member 10 is fixedly connected to the lower end of the conductive plate 12. Both ends of the coil 9 are electrically connected to the conductive member 10. Clamping plates 11 are fixedly connected to both sides of the conductive plate 12, and the two groups of clamping plates 11 are respectively clamped and installed with both sides of the connecting plate 2.

[0029] The conductive plate 12 can be electrically connected to the connecting plate 2 or to an external circuit. The mounting holes of the conductive plate 12 and the connecting plate 2 are aligned, facilitating installation. The coil 9 is powered through the conductive plate 12 and the conductive member 10. The conductive plate 12 is clamped to the connecting plate 2 through the clamping plates 11, preventing the conductive plate 12 from detaching from the connecting plate 2.

[0030] As Figure 1 shown, two connecting ports 17 are opened on one side of the upper end of the bracket 3. Rotating blocks 18 are fixedly connected to the middle parts of both sides of the armature 14, and the two groups of rotating blocks 18 are respectively rotatably connected in the two groups of connecting ports 17.

[0031] The rotating blocks 18 on both sides of the armature 14 are respectively rotatably connected to the two groups of connecting ports 17 on the bracket 3.

[0032] As Figure 1 shown, limiting blocks 16 are fixedly connected to both sides of the lower end of the armature 14. Limiting grooves 15 are opened on both sides of the lower end of the bracket 3. The two groups of limiting blocks 16 are respectively located inside the two groups of limiting grooves 15, and the two groups of limiting blocks 16 are respectively in clamping fit with the inner walls of the two groups of limiting grooves 15.

[0033] The limiting blocks 16 and the limiting grooves 15 limit the rotation amplitude of the lower end of the armature 14, preventing the armature 14 from rotating too much.

[0034] As Figure 3 and Figure 4 shown, a through hole 23 is opened on the side wall of the connecting plate 2. A heat conducting block 24 is fixedly connected to the side of the bimetallic element 6 close to the iron core. The heat conducting block 24 is inserted into the through hole 23, and heat is transferred between the side wall of the heat conducting block 24 and the inner wall of the through hole 23 through an insulating sleeve 25.

[0035] When the bimetallic element 6 is heated and bent, the contact area between the bimetallic element 6 and the connecting plate 2 becomes smaller. After bending to a certain extent, it is restricted. The heat conduction block 24 on the bimetallic element 6 always conducts heat with the through port 23, compensating for the heat conduction of the bimetallic element 6, facilitating the deformation and tripping of the bimetallic element 6. The insulating sleeve 25 prevents the heat conduction block 24 from being electrically connected to the connecting plate 2 and does not affect heat conduction. The insulating sleeve 25 can be made of resin or silicone grease.

[0036] The working principle of an instantaneous protection structure of a molded case circuit breaker provided by the present utility model is as follows:

[0037] When the instantaneous current inside the molded case circuit breaker increases, the temperature of the bimetallic element 6 rises and bends to trip. A coil 9 is installed on the bimetallic element 6. When the current on the connecting plate 1 and the connecting plate 2 increases instantaneously, the current flowing through the coil 9 increases, the magnetic field generated by the coil 9 changes, and the attraction force of the coil 9 on the lower half of the armature 14 increases, driving the armature 14 to rotate. The rotation of the armature 14 drives the circuit breaker to trip. When the current returns to normal, the attraction force of the coil 9 on the lower half of the armature 14 returns to normal, and the spring 22 pulls the armature 14 to reset through the connection end 21, and the instantaneous protection structure returns to its state. By increasing the magnetic attraction driving force of the armature 14 through the coil 9, it assists the rotation of the armature 14 to cause tripping, preventing the insufficient driving of the armature 14 to rotate and cause tripping under low voltage conditions, and facilitating the instantaneous protection of low voltage circuits.

[0038] The above shows and describes the basic principles, main features and advantages of the present utility model. Those skilled in the art of this industry should understand that the present utility model is not limited by the above embodiments. What is described in the above embodiments and the specification only illustrates the principles of the present utility model. Without departing from the spirit and scope of the present utility model, the present utility model will have various changes and improvements, and these changes and improvements all fall within the scope of the present utility model claimed.

Claims

1. An instantaneous protection structure for a molded case circuit breaker, comprising a connection plate (1) and a connection board (2), characterized in that, The connecting plate (1) and the end of the connecting plate (2) are electrically connected. A bracket (3) is fixedly connected to the side wall of the connecting plate (2). A core plate (4) is fixedly connected between the bracket (3) and the connecting plate (2) by a rivet (5). A bimetallic element (6) is fixedly connected to the side of the connecting plate (2) away from the core plate (4). An armature (14) is rotatably connected inside the bracket (3). A coil (9) is clamped to the side of the bimetallic element (6) away from the core. The coil (9) is electrically connected to the connecting plate (2). The coil (9) is magnetically driven in cooperation with one end of the armature (14). A connecting end (21) is fixedly connected to the upper end of the armature (14). A spring (22) is clamped between the end of the connecting end (21) and the upper end of the core plate (4).

2. The instantaneous protection structure of a molded case circuit breaker according to claim 1, wherein, A fixing ring (7) is fixedly connected to the lower end of the side of the bimetallic element (6) away from the core plate (4) by a screw (8). The screw (8) is threadedly connected to the bimetallic element (6) and the connecting plate (2). The coil (9) is clamped on the fixing ring (7).

3. The instantaneous protection structure of a molded case circuit breaker according to claim 2, wherein, A conductive plate (12) is clamped to the lower end of the connecting plate (2). A conductive part (10) is fixedly connected to the lower end of the conductive plate (12). Both ends of the coil (9) are electrically connected to the conductive part (10). Clamping plates (11) are fixedly connected to both sides of the conductive plate (12). The two clamping plates (11) are respectively clamped and installed with both sides of the connecting plate (2).

4. A transient protection structure of a molded case circuit breaker according to claim 1, characterized in that, Two connecting ports (17) are opened on one side of the upper end of the bracket (3). Rotating blocks (18) are fixedly connected to the middle parts of both sides of the armature (14). The two rotating blocks (18) are respectively rotatably connected in the two connecting ports (17).

5. The instantaneous protection structure of a plastic case circuit breaker according to claim 4, characterized in that, Limit blocks (16) are fixedly connected to both sides of the lower end of the armature (14). Limit grooves (15) are opened on both sides of the lower end of the bracket (3). The two limit blocks (16) are respectively located inside the two limit grooves (15), and the two limit blocks (16) are respectively clamped and matched with the inner walls of the two limit grooves (15).

6. The instantaneous protection structure of a molded case circuit breaker according to claim 1, characterized in that, A through hole (23) is opened on the side wall of the connecting plate (2). A heat conduction block (24) is fixedly connected to the side of the bimetallic element (6) close to the core. The heat conduction block (24) is inserted into the through hole (23), and heat is transferred between the side wall of the heat conduction block (24) and the inner wall of the through hole (23) through an insulating sleeve (25).

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