High breaking circuit breaker

Abstract

The utility model relates to a high breaking circuit breaker, which comprises a base, a cover body, an operating mechanism, a moving contact, a static contact, an arc extinguish chamber, an outgoing line wiring board and a conductive copper bar, wherein an electromagnetic current limiting mechanism and a thermomagnetic tripping mechanism are respectively arranged on the conductive copper bar; the electromagnetic current-limiting mechanism comprises a current-limiting magnet yoke which is arranged in the base and sleeves the conductive copper bar, a current-limiting armature which is arranged in the base in a sliding manner and is matched with the current-limiting magnet yoke, and a current-limiting pull plate which is connected between the current-limiting armature and the moving contact, when a short-circuit fault occurs, the current-limiting magnet yoke attracts the current-limiting armature, and the current-limiting pull plate is connected with the moving contact. The current-limiting pull rod acts along with the current-limiting armature and drives the moving contact to execute an opening action, and the thermomagnetic tripping mechanism triggers a draw bar of the operating mechanism to realize tripping and opening of the circuit breaker. The utility model has the advantages of simple structure, stable and reliable performance, long service life, rapid tripping and opening actions and high breaking.

Description

Technical Field

[0001] The utility model relates to the technical field of circuit breakers, in particular to a high-breaking-capacity circuit breaker. Background Art

[0002] A circuit breaker refers to a switching device that can close, carry, and break the current under normal circuit conditions and can also close, carry, and break the current under abnormal circuit conditions within a specified time. The circuit breaker has functions of overload, short-circuit, and under-voltage protection, can protect the circuit and power equipment from damage, and can also provide protection against the potential fire hazard caused by long-term grounding faults that cannot be detected by over-current protection. In order to improve the breaking capacity of the circuit breaker, most of the existing circuit breakers adopt an electro-dynamic repulsion structure design. When a short-circuit fault occurs, the short-circuit current flows through the low-voltage circuit breaker, and the electro-dynamic repulsion between the contacts is used to make the contacts repel in advance, generating an arc voltage to limit the current and improve its breaking performance. However, when the current flowing through the circuit breaker is large enough (such as a short-circuit current), the resultant electro-dynamic repulsion force is greater than the contact spring pressure, and the contacts will quickly repel and start to generate an arc voltage. If the fault current suddenly disappears or is an instantaneous impulse current at this time, it is possible that the moving and static contacts will repel and then fall again, and this reciprocation will cause arcing between the contacts and lead to burnout. In addition, the existence of electro-dynamic repulsion may also affect the stable operation of the circuit breaker, especially in the case of high current, which may cause the breaking performance of the circuit breaker to decline, thereby affecting the safe and stable operation of the entire power system. Summary of the Invention

[0003] The purpose of the utility model is to overcome the defects of the prior art and provide a high-breaking-capacity circuit breaker with a simple structure, stable and reliable performance, long service life, and fast tripping and opening actions.

[0004] To achieve the above purpose, the utility model adopts a high-breaking-capacity circuit breaker, which includes a base, a cover body, an operating mechanism, a moving contact that is linked and cooperated with the operating mechanism, a static contact arranged in the base and cooperating with the moving contact, an arc extinguishing chamber arranged in the base corresponding to the static contact, an outgoing line terminal board arranged in the base, and a conductive copper bar electrically connected between the outgoing line terminal board and the moving contact. The conductive copper bar is respectively provided with an electromagnetic current-limiting mechanism and a thermal-magnetic tripping mechanism. The electromagnetic current-limiting mechanism includes a current-limiting magnetic yoke arranged in the base and sleeved on the conductive copper bar, a current-limiting armature slidably arranged in the base and cooperating with the current-limiting magnetic yoke, and a current-limiting pull plate connected between the current-limiting armature and the moving contact. When a short-circuit fault occurs, the current-limiting magnetic yoke attracts the current-limiting armature, and the current-limiting pull rod moves with the current-limiting armature and drives the moving contact to perform an opening action, and the thermal-magnetic tripping mechanism triggers the traction rod of the operating mechanism to realize the tripping and opening of the circuit breaker.

[0005] The beneficial effects of the above structure are as follows: The electromagnetic current-limiting mechanism adopts an electromagnetic traction type current-limiting structure design. When a short-circuit fault occurs, the electromagnetic current-limiting mechanism can first pull the moving contact to perform the opening operation, and the thermal-magnetic release mechanism triggers the traction rod of the operating mechanism to realize the opening of the circuit breaker, so as to realize the rapid and reliable opening of the circuit breaker. If the fault current suddenly disappears or is an instantaneous impact current at this time, it will not cause the moving and static contacts to repel and then fall again, which can avoid arcing between the contacts and burning, thus contributing to extending the service life of the circuit breaker. During operation, when a short-circuit fault occurs, the conductive copper bar passes a large current, the current-limiting yoke generates a magnetic field, the current-limiting yoke attracts the current-limiting armature to move, and the current-limiting yoke performs the opening operation through the current-limiting pull plate. When the current-limiting pull plate pulls the moving contact apart by a certain distance, the thermal-magnetic release mechanism triggers the traction rod of the operating mechanism, thereby realizing the rapid and reliable opening of the circuit breaker, which is beneficial to improving the breaking capacity of the circuit breaker. Therefore, this circuit breaker has the advantages of simple structure, stable and reliable performance, long service life, and rapid opening operation.

[0006] Particularly, the current-limiting pull plate has two symmetrically distributed pull arms, elastic pins are arranged on the two pull arms, an arc-shaped hole matched with the elastic pins is arranged at one end of the moving contact, the elastic pins are inserted into the arc-shaped hole, and a linkage cooperation between the moving contact and the elastic pins is formed. The current-limiting pull plate is connected to the moving contact through the two pull arms, so as to ensure more reliable transmission between the current-limiting pull plate and the moving contact. And the two pull arms are connected to the moving contact through the elastic pins, which is convenient for more convenient assembly of the current-limiting pull plate and the moving contact.

[0007] Particularly, the current-limiting armature has two symmetrically distributed attracting parts that cooperate with the current-limiting yoke. Two sliding grooves that cooperate with the two attracting parts are arranged in the base. The two attracting parts are respectively slidably arranged in the two sliding grooves, and a sliding connection cooperation between the two attracting parts and the base is formed. The two attracting parts of the current-limiting armature are slidably arranged in the sliding grooves of the base, so as to ensure that the current-limiting armature can act reliably in the base, which is beneficial to improving the working reliability of this electromagnetic current-limiting mechanism.

[0008] Particularly, the current-limiting yoke has two attracting arms that cooperate with the two attracting parts, attracting planes that cooperate with the attracting parts are arranged on the two attracting arms, and contact planes that cooperate with the attracting planes are arranged on the two attracting parts. The current-limiting yoke is attracted to the contact plane of the current-limiting armature through the attracting plane, so as to ensure reliable attraction between the current-limiting yoke and the current-limiting armature, which is beneficial to improving the working reliability of this electromagnetic current-limiting mechanism.

[0009] Particularly, a receiving groove is formed between two attracting arms of the current-limiting yoke, and the conductive copper bar is inserted into the receiving groove. The conductive copper bar is inserted into the receiving groove of the current-limiting yoke, thereby ensuring more reliable contact between the current-limiting yoke and the conductive copper bar.

[0010] Particularly, screws are arranged in the base and are matched with the current-limiting yoke and the conductive copper bar. Through holes are arranged on the current-limiting yoke and are matched with the screws. Threaded holes are arranged on the conductive copper bar and are matched with the screws. The screws pass through the through holes and are connected in the threaded holes. The base is connected to the current-limiting yoke and the conductive copper bar through screws, thereby facilitating the assembly of the current-limiting yoke, the conductive copper bar and the base, and having higher assembly efficiency.

[0011] Particularly, the thermal magnetic release mechanism includes a yoke arranged on the conductive copper bar, an armature rotatably arranged in the base and matched with the yoke, a tension spring arranged between the yoke and the armature, a bimetallic strip arranged on the conductive copper bar, and a push rod arranged at one end of the bimetallic strip and used to trigger the traction rod to perform a release action. One end of the armature has a trigger part for triggering the traction rod to perform a release action. The other end of the armature has a suction contact part matched with the yoke. A suction plate is folded outward at the tail of the suction contact part. The thermal magnetic release mechanism adopts a modular structure design, thereby realizing the modular assembly of the thermal magnetic release mechanism and the conductive copper bar. A suction plate is folded outward at the tail of the suction contact part of the armature, thereby increasing the suction force between the suction contact part and the yoke, and being beneficial to improving the working reliability of the thermal magnetic release mechanism.

[0012] Particularly, the armature has two symmetrically distributed support arms. Two arc-shaped grooves are arranged in the base and are matched with the two support arms. The two support arms are respectively rotatably arranged in the two arc-shaped grooves, and form a rotational connection and cooperation between the two support arms and the base. The armature is rotatably arranged in the arc-shaped grooves of the base through the two support arms, thereby ensuring that the armature can rotate reliably in the base, ensuring reliable suction between the armature and the magnet, and being beneficial to improving the working reliability of the thermal magnetic release mechanism. Description of the Drawings

[0013] Figure 1 It is a cross-sectional view of an embodiment of the present invention.

[0014] Figure 2 It is an internal structure diagram of an embodiment of the present invention.

[0015] Figure 3 It is an assembly drawing of the electromagnetic current-limiting mechanism and the thermal magnetic release mechanism of an embodiment of the present invention.

[0016] Figure 4 It is an exploded view of the electromagnetic current-limiting mechanism of an embodiment of the present invention. Detailed Embodiments

[0017] such as Figures 1 to 4As shown in the figure, an embodiment of the utility model is a high-breaking circuit breaker, which includes a base 10, a cover 11, an operating mechanism 12, a moving contact 13 that is linked and cooperated with the operating mechanism 12, a static contact 14 arranged in the base 10 and cooperated with the moving contact 13, an arc extinguishing chamber 15 arranged in the base 10 corresponding to the static contact 14, an outgoing line terminal board 16 arranged in the base 10, and a conductive copper bar 17 electrically connected between the outgoing line terminal board 16 and the moving contact 13. The conductive copper bar 17 is connected to one end of the moving contact 13 through a copper braid 170. An electromagnetic current limiting mechanism 20 and a thermal magnetic trip mechanism 30 are respectively arranged on the conductive copper bar 17. The electromagnetic current limiting mechanism 20 includes a current limiting magnetic yoke 21 arranged in the base 10 and sleeved on the conductive copper bar 17, a current limiting armature 22 slidably arranged in the base 10 and cooperated with the current limiting magnetic yoke 21, and a current limiting pull plate 23 connected between the current limiting armature 22 and the moving contact 13. When a short-circuit fault occurs, the current limiting magnetic yoke 21 attracts the current limiting armature 22, and the current limiting pull rod 23 moves with the current limiting armature 22 and drives the moving contact 13 to perform a tripping action. Moreover, the thermal magnetic trip mechanism 30 triggers the draw rod 121 of the operating mechanism 12 to realize the tripping and opening of the circuit breaker. The current limiting pull plate 23 has two symmetrically distributed pull arms 231, and elastic pins 232 are arranged on the two pull arms 231. An arc-shaped hole 131 cooperated with the elastic pins 232 is arranged at one end of the moving contact 13. The elastic pins 232 are inserted into the arc-shaped hole 131, and the linkage cooperation between the moving contact 13 and the elastic pins 232 is formed. The current limiting pull plate is connected to the moving contact through two pull arms, so as to ensure that the transmission between the current limiting pull plate and the moving contact is more reliable. And the two pull arms are connected to the moving contact through elastic pins, so as to facilitate the assembly of the current limiting pull plate and the moving contact more conveniently. The current limiting armature 22 has two symmetrically distributed attracting parts 221 cooperated with the current limiting magnetic yoke 21. Two sliding grooves 101 cooperated with the two attracting parts 221 are arranged in the base 10. The two attracting parts 221 are respectively slidably arranged in the two sliding grooves 101, and the sliding connection cooperation between the two attracting parts 221 and the base 10 is formed. The two attracting parts of the current limiting armature are slidably arranged in the sliding grooves of the base, so as to ensure that the current limiting armature can act reliably in the base, which is beneficial to improving the working reliability of the electromagnetic current limiting mechanism. The current limiting magnetic yoke 21 has two attracting arms 211 cooperated with the two attracting parts 221. Attracting planes 2111 cooperated with the attracting parts 221 are arranged on the two attracting arms 211. Contact planes 2211 cooperated with the attracting planes 2111 are arranged on the two attracting parts 221. The current limiting magnetic yoke is attracted to the current limiting armature through the attracting plane and the contact plane, so as to ensure that the current limiting magnetic yoke and the current limiting armature can be attracted reliably, which is beneficial to improving the working reliability of the electromagnetic current limiting mechanism. A receiving groove 2110 is formed between the two attracting arms 211 of the current limiting magnetic yoke 21, and the conductive copper bar 17 is inserted into the receiving groove 2110.The conductive copper bar is inserted into the accommodation groove of the current-limiting yoke, so as to ensure more reliable contact between the current-limiting yoke and the conductive copper bar. A screw 18 is arranged in the base 10 and is matched with the current-limiting yoke 21 and the conductive copper bar 17. A through hole 212 is arranged on the current-limiting yoke 21 and is matched with the screw 18. A threaded hole 171 is arranged on the conductive copper bar 17 and is matched with the screw 18. The screw 18 passes through the through hole 212 and is connected in the threaded hole 171. The base is connected to the current-limiting yoke and the conductive copper bar through screws, which facilitates the assembly of the current-limiting yoke, the conductive copper bar and the base, and the assembly efficiency is higher.

[0018] As Figure 1 , 2 , as shown in Figure 3, the thermal magnetic release mechanism 30 includes a yoke 31 arranged on the conductive copper bar 17, an armature 32 rotatably arranged in the base 10 and matched with the yoke 31, a tension spring 33 arranged between the yoke 31 and the armature 32, a bimetallic strip 34 arranged on the conductive copper bar 17, and a push rod 35 arranged at one end of the bimetallic strip 34 and used to trigger the release lever 121 to perform the release action. One end of the armature 32 has a triggering portion 321 for triggering the release lever 121 to perform the release action. The other end of the armature 32 has a suction contact portion 322 matched with the yoke 31. A suction plate 323 is folded outwards at the tail of the suction contact portion 322. The thermal magnetic release mechanism adopts a modular structure design, so as to realize the modular assembly of the thermal magnetic release mechanism and the conductive copper bar. The tail of the suction contact portion of the armature is folded outwards and attached with a suction plate, so as to increase the suction force between the suction contact portion and the yoke, which is beneficial to improving the working reliability of the thermal magnetic release mechanism. The armature 32 has two symmetrically distributed support arms 324. Two arc-shaped grooves 102 are arranged in the base 10 and are matched with the two support arms 324. The two support arms 324 are respectively rotatably arranged in the two arc-shaped grooves 102, and form a rotational connection and cooperation between the two support arms 324 and the base 10. The armature is rotatably arranged in the arc-shaped groove of the base through two support arms, so as to ensure that the armature can rotate reliably in the base and ensure reliable suction between the armature and the magnet, which is beneficial to improving the working reliability of the thermal magnetic release mechanism.

[0019] The electromagnetic current-limiting mechanism adopts an electromagnetic traction type current-limiting structure design. When a short-circuit fault occurs, the electromagnetic current-limiting mechanism can first pull the moving contact to perform the opening operation, and the thermal-magnetic tripping mechanism triggers the traction rod of the operating mechanism to realize the tripping and opening of the circuit breaker, so as to realize the rapid and reliable tripping and opening of the circuit breaker. If the fault current suddenly disappears or is an instantaneous impact current at this time, it will not cause the moving and static contacts to repel and then fall again, which can avoid causing arcing between the contacts and resulting in burnout, thus being beneficial to extending the service life of the circuit breaker. During operation, when a short-circuit fault occurs, the conductive copper bar passes through a large current, the current-limiting yoke generates a magnetic field, the current-limiting yoke attracts the current-limiting armature to move, the current-limiting yoke performs the opening operation through the current-limiting pull plate. When the current-limiting pull plate pulls the moving contact apart by a certain distance, the thermal-magnetic tripping mechanism triggers the traction rod of the operating mechanism, thereby realizing the rapid and reliable tripping and opening of the circuit breaker, which is beneficial to improving the breaking capacity of the circuit breaker. Therefore, this circuit breaker has the advantages of simple structure, stable and reliable performance, long service life, and rapid tripping and opening action.

Claims

1. A high-breaking circuit breaker, comprising a base, a cover body, an operating mechanism, a moving contact that is linked and cooperated with the operating mechanism, a static contact arranged in the base and cooperated with the moving contact, an arc extinguishing chamber arranged in the base corresponding to the static contact, an outgoing wire connection board arranged in the base, and a conductive copper bar electrically connected between the outgoing wire connection board and the moving contact, characterized in that: An electromagnetic current-limiting mechanism and a thermal-magnetic release mechanism are respectively arranged on the conductive copper bar. The electromagnetic current-limiting mechanism includes a current-limiting magnetic yoke arranged in the base and sleeved on the conductive copper bar, a current-limiting armature slidably arranged in the base and cooperating with the current-limiting magnetic yoke, and a current-limiting pull plate connected between the current-limiting armature and the moving contact. When a short-circuit fault occurs, the current-limiting magnetic yoke attracts the current-limiting armature, the current-limiting pull plate moves with the current-limiting armature and drives the moving contact to perform a tripping action, and the thermal-magnetic release mechanism triggers the traction rod of the operating mechanism to realize the tripping and opening of the circuit breaker.

2. The high-breaking circuit breaker according to claim 1, wherein: The current-limiting pull plate has two symmetrically distributed pull arms, elastic pins are arranged on the two pull arms, an arc-shaped hole cooperating with the elastic pins is arranged at one end of the moving contact, and the elastic pins are inserted into the arc-shaped hole, forming a linkage cooperation between the moving contact and the elastic pins.

3. The high-breaking circuit breaker according to claim 1 or 2, characterized in that: The current-limiting armature has two symmetrically distributed attracting parts cooperating with the current-limiting magnetic yoke, two sliding grooves cooperating with the two attracting parts are arranged in the base, and the two attracting parts are respectively slidably arranged in the two sliding grooves, forming a sliding connection cooperation between the two attracting parts and the base.

4. The high-breaking circuit breaker according to claim 3, characterized in that: The current-limiting magnetic yoke has two attracting arms cooperating with the two attracting parts, attracting planes cooperating with the attracting parts are arranged on the two attracting arms, and contact planes cooperating with the attracting planes are arranged on the two attracting parts.

5. The high-breaking circuit breaker according to claim 4, characterized in that: A receiving groove is formed between the two attracting arms of the current-limiting magnetic yoke, and the conductive copper bar is inserted into the receiving groove.

6. The high-breaking circuit breaker according to claim 1 or 2, characterized in that: Screws cooperating with the current-limiting magnetic yoke and the conductive copper bar are arranged in the base, through holes cooperating with the screws are arranged on the current-limiting magnetic yoke, threaded holes cooperating with the screws are arranged on the conductive copper bar, and the screws pass through the through holes and are connected in the threaded holes.

7. The high-breaking circuit breaker according to claim 1, characterized in that: The thermal-magnetic release mechanism includes a magnetic yoke arranged on the conductive copper bar, an armature rotatably arranged in the base and cooperating with the magnetic yoke, a tension spring arranged between the magnetic yoke and the armature, a bimetallic strip arranged on the conductive copper bar, and a push rod arranged at one end of the bimetallic strip and used to trigger the traction rod to perform a tripping action. One end of the armature has a triggering part for triggering the traction rod to perform a tripping action, the other end of the armature has an attracting contact part cooperating with the magnetic yoke, and an attracting plate is folded outwards and attached to the tail of the attracting contact part.

8. The high-breaking circuit breaker according to claim 7, characterized in that: The armature has two symmetrically distributed supporting arms, two arc-shaped grooves cooperating with the two supporting arms are arranged in the base, and the two supporting arms are respectively rotatably arranged in the two arc-shaped grooves, forming a rotational connection cooperation between the two supporting arms and the base.

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