Circuit breaker with multiple protection

Abstract

The invention discloses a circuit breaker with multiple protections. The circuit breaker comprises a shell; the first terminal and the second terminal are both arranged on the shell; the contact arm is rotatably mounted in the shell; the triggering mechanism comprises a pushing piece and a limiting buckle abutting against the pushing piece, and the limiting buckle is buckled with the contact arm so as to limit rotation of the contact arm; the bimetallic strip is in contact with the first terminal and is connected with the limiting buckle; the fuse element is attached to the bimetallic strip; and the rotating piece is connected with the fusing piece, and when the fusing piece is fused, the rotating piece can rotate to push the bimetallic strip. The temperature of the bimetallic strip can be transmitted to the fusing piece, so that the fusing piece is fused, the limiting on the rotating piece is relieved, the rotating piece rotates, the bimetallic strip is pushed to be bent, the bimetallic strip pulls the limiting buckle through the handle to rotate to unlock the contact arm, the contact arm rotates clockwise, at the moment, the contact arm is separated from the second terminal, and the circuit is disconnected.

Description

Technical Field

[0001] The present invention relates to the field of power plant circuit breakers, in particular to a circuit breaker with multiple protections. Background Art

[0002] A circuit breaker is a switching device capable of closing, carrying, and interrupting current under normal circuit conditions, and closing, carrying, and interrupting current under abnormal circuit conditions within a specified timeframe. Circuit breakers are categorized as high-voltage and low-voltage based on their scope of use. The distinction between high and low voltage is relatively vague, with those above 3kV generally considered high-voltage. Circuit breakers can be used to distribute electrical energy, infrequently start asynchronous motors, and protect power lines and motors. They can automatically disconnect circuits in the event of severe overloads, short circuits, undervoltages, or other faults. Circuit breakers are commonly used in thermal power plants.

[0003] Common circuit breakers used in thermal power plants generally consist of a contact system, arc extinguishing system, operating mechanism, trip unit, and housing. When a short circuit occurs, the magnetic field generated by the high current overcomes the reaction spring, causing the trip unit to pull the operating mechanism into action, instantly tripping the switch. When overloaded, the current increases, generating more heat, and the bimetallic strip deforms to a certain degree, causing the mechanism to operate (the higher the current, the shorter the operating time). This is a common circuit breaker structure and operating principle. Before use, the circuit breaker must be installed at the designated location in the thermal power plant, and the exposed ends of the corresponding wires must be inserted into the corresponding ports of the circuit breaker and connected, allowing the circuit breaker to operate normally.

[0004] Overload protection is one of the basic functions of a circuit breaker. It is primarily based on thermal effects and uses a bimetallic strip or thermal element. When the current exceeds the set value, the current passing through the heating element generates heat, causing the bimetallic strip to bend, triggering the circuit breaker and cutting off the power supply. However, due to aging of the bimetallic strip, the bending amount varies, resulting in non-operation. Summary of the Invention

[0005] Therefore, the technical problem to be solved by the present invention is: aging of the bimetallic strip.

[0006] The above technical problem is solved by the following technical solution: The present invention provides a circuit breaker with multiple protections, which includes a housing;

[0007] a first terminal and a second terminal, both of which are provided on the housing;

[0008] A contact arm rotatably mounted inside the housing;

[0009] The trigger mechanism includes a pusher and a limit buckle abutting against the pusher, wherein the limit buckle is engaged with the contact arm to limit the rotation of the contact arm;

[0010] A bimetallic strip is in contact with the first terminal and is connected to the limit buckle;

[0011] The fuse is bonded to the bimetallic strip;

[0012] The rotating member is connected to the fuse, and when the fuse is blown, the rotating member can rotate and push the bimetallic strip;

[0013] The first terminal and the second terminal are electrically connected via a bimetallic strip, a trigger mechanism, and a contact arm.

[0014] In a preferred embodiment of the circuit breaker with multiple protections described in the present invention: the bimetallic strip includes a contact end connected to the first terminal, a first metal body and a second metal body connected to the contact end and fitted together, and a handle provided to connect the first metal body and the limit buckle.

[0015] In a preferred embodiment of the circuit breaker with multiple protections of the present invention, it further comprises a mounting member, the fuse is mounted on the mounting member, and the rotating member is mounted on the mounting member via an automatic rebound rotating shaft.

[0016] In a preferred embodiment of the circuit breaker with multiple protections of the present invention: the mounting member includes a fixing portion connected to the housing, and a boss provided on the fixing portion, and the fuse is provided on the boss.

[0017] In a preferred embodiment of the circuit breaker with multiple protections of the present invention: the rotating member includes a rotating body and an extrusion protrusion, the rotating body is mounted on the mounting member via an automatic rebound rotating shaft, and the extrusion protrusion contacts the bimetallic strip;

[0018] When the rotating body rotates, the extrusion protrusion can push the bimetallic strip to bend and deform.

[0019] In a preferred embodiment of the circuit breaker with multiple protections of the present invention: one end of the contact arm is a limit end, and the limit end is provided with a buckle groove;

[0020] One end of the limiting buckle is provided with a buckle opening, and when the buckle opening is buckled with the buckle groove, the contact arm can be limited.

[0021] In a preferred embodiment of the circuit breaker with multiple protections of the present invention, the pushing member includes a fixed tube fixed inside the housing, a movable pin movably mounted on the fixed tube, and an elastic member abutting against the movable pin;

[0022] The end of the limit buckle away from the buckle opening is a force-bearing end, the movable pin is against the force-bearing end, and the bimetallic sheet is also connected to the force-bearing end.

[0023] In a preferred embodiment of the circuit breaker with multiple protections of the present invention: the pushing member further includes a coil wound around the outside of the fixed tube.

[0024] In a preferred embodiment of the circuit breaker with multiple protections of the present invention: a bow head is provided at the end of the contact arm away from the limiting end, and the bow head can contact the second terminal.

[0025] In a preferred embodiment of the circuit breaker with multiple protections of the present invention: the second terminal is connected to an extended metal sheet, and an arc extinguishing chamber connected to the extended metal sheet is further provided inside the housing.

[0026] The beneficial effect of the present invention is that: by setting a fuse and a rotating part, when the bimetallic strip bends normally, the bimetallic strip can bend in the direction away from the limit buckle and thus detach from the fuse. In this case, the temperature of the bimetallic strip cannot be transmitted to the fuse, and the fuse will not blow. When the bimetallic strip is aged and the bending amplitude is small, the bimetallic strip cannot completely detach from the fuse. At this time, the temperature of the bimetallic strip can be transmitted to the fuse, causing the fuse to blow, thereby releasing the limit on the rotating part, and the rotating part rotates, pushing the bimetallic strip to bend. The bimetallic strip pulls the limit buckle through the handle to rotate and unlock the contact arm, and the contact arm rotates clockwise. At this time, the contact arm and the second terminal are detached, thereby disconnecting the circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings of the embodiments of the present invention. Obviously, the drawings described below only relate to some embodiments of the present invention and are not intended to limit the present invention. Among them:

[0028] Figure 1 Shows the overall structure of a circuit breaker with multiple protections;

[0029] Figure 2 A diagram showing a connected state of a first terminal and a second terminal of a circuit breaker with multiple protections is shown;

[0030] Figure 3 Shows a schematic structural diagram of the fuse and the rotating part;

[0031] Figure 4 An exploded view of the structure of the fuse and the rotating part is shown;

[0032] Figure 5 The internal structure diagram of the circuit breaker with multiple protections is shown;

[0033] Figure 6 Shows the specific structure of the limit buckle and contact arm;

[0034] Figure 7The specific structure diagram of the pusher is shown.

[0035] 100. Shell; 101. Arc extinguishing chamber; 200. First terminal; 300. Second terminal; 301. Extended metal sheet; 400. Contact arm; 401. Limiting end; 402. Buckle groove; 403. Bow head; 500. Trigger mechanism; 501. Pushing member; 5011. Fixed tube; 5012. Movable pin; 5013. Elastic member; 5014. Coil; 502. Limiting buckle; 5021. Buckle mouth; 5022. Force-bearing end; 600. Bimetallic strip; 601. Contact end; 602. First metal body; 603. Second metal body; 604. Handle; 700. Fuse; 800. Rotating member; 801. Rotating body; 802. Extrusion protrusion; 900. Mounting member; 901. Fixing part; 902. Boss; 903. Snap buckle; X1. First conductor; X2. Second conductor. DETAILED DESCRIPTION

[0036] In order to enable those skilled in the art to better understand the present invention, the present invention is further described in detail below with reference to specific embodiments and the accompanying drawings.

[0037] The terms used in the present invention are those commonly used in the art in view of the functions of the present invention, but these terms may vary according to the intentions of those skilled in the art, precedents, or new technologies in the art. In addition, specific terms may be selected by the applicant, and in such cases, their detailed meanings will be described in the detailed description of the present invention. Therefore, the terms used in the specification should not be understood as simple names, but rather as the meanings of the terms and the overall description of the present invention.

[0038] Reference Figures 1 to 7The present embodiment provides a circuit breaker with multiple protections, including a housing 100; a first terminal 200 and a second terminal 300, both of which are provided on the housing 100; the first terminal 200 and the second terminal 300 are respectively installed at both ends of the housing 100, and the first terminal 200 and the second terminal 300 are made of conductive metal as a whole, such as copper, and the housing 100 is provided with wire openings at corresponding positions of the first terminal 200 and the second terminal 300, through which wires can be inserted into the interior of the first terminal 200 and the second terminal 300, and fixing bolts are installed on the first terminal 200 and the second terminal 300. When the wires are inserted into the first terminal 200 and the second terminal 300, the first terminal 200 and the second terminal 300 are fixed. After being inserted into the second terminal 300, the fixing bolt can be rotated and locked to fix the wire to the first terminal 200 and the second terminal 300. In actual use, the circuit breaker is located between the two wires to connect the two wires. For example, the two wires are a first wire X1 and a second wire X2. The first wire X1 is connected to the first terminal 200, and the second wire X2 is connected to the second terminal 300. In this way, the first wire X1 and the second wire X2 can be connected through the circuit breaker. When a circuit break or overload occurs, the circuit breaker disconnects the first wire X1 and the second wire X2, thereby disconnecting the circuit and preventing damage to the power equipment due to a short circuit.

[0039] The circuit breaker also includes a contact arm 400, which is rotatably mounted inside the housing 100. Similar to the prior art, the contact arm 400 is rotatably mounted inside the housing 100 via an axial connection, and a torsion spring is provided between the contact arm 400 and the housing 100. When the contact arm 400 is released from the restriction, it can rotate clockwise under the action of the torsion spring, thereby disconnecting the contact arm 400 from the second terminal 300, thereby achieving the effect of disconnecting the circuit.

[0040] The circuit breaker further includes a trigger mechanism 500, including a pusher 501 and a limit buckle 502 that abuts against the pusher 501. The limit buckle 502 is interlocked with the contact arm 400 to limit the rotation of the contact arm 400. When in the connected state, the limit buckle 502 is interlocked with the contact arm 400, so that the contact arm 400 cannot rotate clockwise under the action of the torsion spring. When a short circuit occurs, the pusher 501 can push the limit buckle 502, causing the limit buckle 502 to rotate. At this time, the limit buckle 502 disengages from the contact arm 400 due to the rotation. Under the action of the torsion spring, the contact arm 400 rotates clockwise, causing the contact arm 400 to disengage from the second terminal 300, thereby achieving a circuit breaker effect.

[0041] The circuit breaker further includes a bimetallic strip 600, which contacts the first terminal 200 and is connected to the limit buckle 502. The bimetallic strip 600 is made of two different metals. Because the two metals deform differently under heat at the same temperature, if excessive use of electrical equipment on the line causes the line to overload, the bimetallic strip 600 will deflect due to heat, thereby pulling the limit buckle 502 to rotate. The limit buckle 502 disengages from the contact arm 400, allowing the contact arm 400 to release its restraint and rotate clockwise under the action of the torsion spring, thereby disengaging from the second terminal 300.

[0042] In order to avoid the problem that the bimetallic strip 600 is not bent enough due to aging and thus cannot be disconnected in time, the circuit breaker further includes a fuse 700, which is attached to the bimetallic strip 600; a rotating member 800, which is connected to the fuse 700. When the fuse 700 is blown, the rotating member 800 can rotate and push the bimetallic strip 600; the first terminal 200 and the second terminal 300 are electrically connected through the bimetallic strip 600, the trigger mechanism 500, and the contact arm 400. If the bimetallic strip 600 is bent normally due to heat, the bimetallic strip 600 will bend normally. When the bimetallic strip 600 is bent, it will separate from the fuse 700, and the fuse 700 will not melt. When the bending amplitude of the bimetallic strip 600 is too small due to heat, the high-temperature bimetallic strip 600 will not completely separate from the fuse 700. At this time, the fuse 700 is always affected by the temperature of the bimetallic strip 600 and melts, thereby releasing the limit on the rotating part 800. The rotating part 800 rotates, pushing the bimetallic strip 600 to deform, causing the bimetallic strip 600 to pull the limit buckle 502 to rotate, so that the limit buckle 502 releases the limit on the contact arm 400.

[0043] The bimetallic strip 600 includes a contact end 601 connected to the first terminal 200, a first metal body 602 and a second metal body 603 connected to the contact end 601 and fitted together, and a handle 604 provided to connect the first metal body 602 and the limit buckle 502. In this embodiment, the contact end 601 is fitted with the first terminal 200, and the first terminal 200 can transmit current to the contact end 601, thereby conducting it to the bimetallic strip 600. The first metal body 602 and the second metal body 603 are made of different metal materials. The handle 604 generally adopts a U-shaped structure, one end of which is connected to the bimetallic strip 600 and the other end is fitted with the limit buckle 502. When the line is overloaded, the first metal body 602 and the second metal body 603 bend away from the limit buckle 502 due to the different thermal deformation amounts, so that the limit buckle 502 can be pulled to rotate by the handle 604.

[0044] The circuit breaker also includes a mounting member 900, on which the fuse 700 is mounted, and on which the rotating member 800 is mounted via an automatic rebound shaft. The mounting member 900 includes a fixing portion 901 connected to the housing 100, and a boss 902 provided on the fixing portion 901, on which the fuse 700 is provided. As shown in the figure, the entire fixing portion 901 is a sheet-mounted structure, which is fitted with the shell 100, and the boss 902 is arranged perpendicular to the fixing portion 901. The boss 902 is installed on the side of the bimetallic strip 600 facing the fuse 700, and the fuse 700 and the bimetallic strip 600 remain in a fitted state. Under normal conditions, the temperature of the bimetallic strip 600 is not high and will not deform, and the temperature cannot cause the fuse 700 to melt. When the line is overloaded, the temperature of the bimetallic strip 600 rises. At this time, the temperature of the bimetallic strip 600 can be transferred to the fuse 700. When the bimetallic strip 600 bends normally, the bimetallic strip 600 can bend away from the limit buckle 502 to disengage from the fuse. The fuse 700 is broken. In this case, the temperature of the bimetallic strip 600 cannot be transferred to the fuse 700, and the fuse 700 will not melt. When the bimetallic strip 600 is aged and the bending amplitude is small, the bimetallic strip 600 cannot be completely separated from the fuse 700. At this time, the temperature of the bimetallic strip 600 can be transferred to the fuse 700, causing the fuse 700 to melt, thereby releasing the limit on the rotating part 800. The rotating part 800 rotates, pushing the bimetallic strip 600 to bend, and the bimetallic strip 600 pulls the limit buckle 502 through the handle 604 to rotate and unlock the contact arm 400. The contact arm 400 rotates clockwise, and the contact arm 400 and the second terminal 300 are separated.

[0045] The rotating member 800 includes a rotating body 801 and an extrusion protrusion 802. The rotating body 801 is mounted on the mounting member 900 through an automatic rebound rotating shaft. The extrusion protrusion 802 contacts the bimetallic strip 600. In this embodiment, the extrusion protrusion 802 and the end of the bimetallic strip 600 near the limit buckle 502 are against each other. One end of the fuse 700 is fixed on the boss 902, and the other end of the fuse 700 is connected to the extrusion protrusion 802, so that the fuse 700 can be limited. The rotating body 801 prevents it from rotating. When the fuse 700 blows, the rotating body 801 rotates counterclockwise under the action of the automatic rebound shaft. The extrusion protrusion 802 of the rotating body 800 pushes the bimetallic strip 600 away from the limit buckle 502, causing the bimetallic strip 600 to bend and deform. At this time, the bimetallic strip 600 can pull the limit buckle 502 to rotate through the handle 604, so that the limit buckle 502 unlocks the contact arm 400.

[0046] A snap buckle 903 is also provided on the fixing portion 901. The snap buckle 903 is composed of two L-shaped protrusions with a gap between the two L-shaped protrusions. The bimetallic strip 600 passes through the gap and remains in contact with the two L-shaped protrusions. The function of the snap buckle 903 is first to limit the bimetallic strip 600 so that the position of the bimetallic strip 600 is stable. Second, when the rotating part 800 refunds the bimetallic strip 600, due to the limitation of the snap buckle 903, the end of the bimetallic strip 600 equipped with the handle 604 can be stably bent and deformed.

[0047] One end of the contact arm 400 is a limiting end 401, and the limiting end 401 is provided with a buckle groove 402; one end of the limiting buckle 502 has a buckle opening 5021, and when the buckle opening 5021 is buckled with the buckle groove 402, it can limit the contact arm 400. When the limiting buckle 502 rotates clockwise, the buckle can be detached from the inside of the buckle groove 402. In this case, the limitation of the contact arm 400 can be released. Under the action of the torsion spring, the contact arm 400 rotates clockwise, and the contact arm 400 and the second terminal 300 are detached, thereby disconnecting.

[0048] The pusher 501 comprises a fixed tube 5011 fixed to the interior of the housing 100, a movable pin 5012 movably mounted on the fixed tube 5011, and an elastic member 5013 that abuts against the movable pin 5012. The pusher 501 also comprises a coil 5014 wound around the exterior of the fixed tube 5011. The end of the stopper 502, away from the opening 5021, serves as a force-bearing end 5022. The movable pin 5012 abuts against the force-bearing end 5022, and the bimetallic strip 600 is also connected to the force-bearing end 5022.

[0049] Under normal conditions, the movable pin 5012 cannot overcome the elastic force of the elastic member 5013 and move in the X direction. When a short circuit occurs in the circuit, the current flowing through the coil 5014 will increase instantaneously. At this time, under the electromagnetic action, the magnetic field of the coil 5014 can push the movable pin 5012, causing the movable pin 5012 to move in the X direction. At this time, the movable pin 5012 overcomes the elastic force of the elastic member 5013 and moves in the X direction. The end of the movable pin 5012 pushes the force-bearing end 5022 of the limit buckle 502, causing the limit buckle 502 to rotate clockwise, thereby unlocking the contact arm 400, thereby disconnecting the circuit in time in the event of a short circuit.

[0050] The end of the contact arm 400 away from the limiting end 401 is provided with a bow head 403, which can contact the second terminal 300. The second terminal 300 is connected to the extended metal sheet 301. The interior of the housing 100 is also provided with an arc extinguishing chamber 101 connected to the extended metal sheet 301.

[0051] The bow head 403 is used to contact the extended metal sheet 301 of the second terminal 300. When the bow head 403 contacts the extended metal sheet 301, the contact arm 400 and the second terminal 300 are in the connected state, and the first terminal 200 and the second terminal 300 are kept in the connected state through the bimetallic strip 600, the limit buckle 502, and the contact arm 400. When the contact arm 400 rotates clockwise and disengages from the extended metal sheet 301, the connection between the first terminal 200 and the second terminal 300 can be disconnected. In addition, during the disconnection process, the arc generated between the bow head 403 and the extended metal sheet 301 is led to the arc extinguishing chamber 101 for arc extinguishing.

[0052] Finally, it should be pointed out that the methods and devices described in detail above are merely embodiments, and those skilled in the art can modify these embodiments in different ways without departing from the scope of the present invention.

Claims

1. A circuit breaker with multiple protections, characterized by: include, Housing (100); A first terminal (200) and a second terminal (300), both of which are provided on the housing (100); A contact arm (400) rotatably mounted inside the housing (100); The trigger mechanism (500) comprises a push member (501) and a limit buckle (502) abutting against the push member (501), wherein the limit buckle (502) is locked with the contact arm (400) to limit the rotation of the contact arm (400); A bimetallic strip (600) contacts the first terminal (200) and is connected to the limit buckle (502); The fuse (700) is bonded to the bimetallic strip (600); The rotating member (800) is connected to the fuse member (700), and when the fuse member (700) is blown, the rotating member (800) can rotate to push the bimetallic strip (600); The first terminal (200) and the second terminal (300) are electrically connected via a bimetallic strip (600), a trigger mechanism (500), and a contact arm (400).

2. The circuit breaker with multiple protections according to claim 1, characterized in that: The bimetallic strip (600) comprises a contact end (601) connected to the first terminal (200), a first metal body (602) and a second metal body (603) connected to the contact end (601) and fitted together, and a handle (604) provided to connect the first metal body (602) and the limit buckle (502).

3. The circuit breaker with multiple protections according to claim 1, characterized in that: It also includes a mounting member (900), the fuse member (700) is mounted on the mounting member (900), and the rotating member (800) is mounted on the mounting member (900) via an automatic rebound rotating shaft.

4. The circuit breaker with multiple protections according to claim 3, characterized in that: The mounting member (900) comprises a fixing portion (901) connected to the housing (100), and a boss (902) provided on the fixing portion (901), and the fuse (700) is provided on the boss (902).

5. The circuit breaker with multiple protections according to claim 3, characterized in that: The rotating member (800) includes a rotating body (801) and an extrusion protrusion (802), wherein the rotating body (801) is mounted on the mounting member (900) via an automatic rebound rotating shaft, and the extrusion protrusion (802) contacts the bimetallic strip (600); When the rotating body (801) rotates, the extrusion protrusion (802) can push the bimetallic strip (600) to bend and deform.

6. The circuit breaker with multiple protections according to claim 1, characterized in that: One end of the contact arm (400) is a limiting end (401), and the limiting end (401) is provided with a buckling groove (402); One end of the limiting buckle (502) has a buckle opening (5021), and when the buckle opening (5021) is buckled with the buckle groove (402), it can limit the contact arm (400).

7. The circuit breaker with multiple protections according to claim 6, characterized in that: The pushing member (501) comprises a fixed tube (5011) fixed inside the housing (100), a movable pin (5012) movably mounted on the fixed tube (5011), and an elastic member (5013) abutting against the movable pin (5012); The end of the limit buckle (502) away from the buckle opening (5021) is the force-bearing end (5022), the movable pin (5012) is against the force-bearing end (5022), and the bimetallic strip (600) is also connected to the force-bearing end (5022).

8. The circuit breaker with multiple protections according to claim 7, characterized in that: The pushing member (501) further includes a coil (5014) wound around the outside of the fixed tube (5011).

9. The circuit breaker with multiple protections according to claim 6, characterized in that: The end of the contact arm (400) away from the limiting end (401) is provided with a bow head (403), and the bow head (403) is capable of contacting the second terminal (300).

10. The circuit breaker with multiple protections according to claim 1, characterized in that: The second terminal (300) is connected to an extended metal sheet (301), and an arc extinguishing chamber (101) connected to the extended metal sheet (301) is further provided inside the housing (100).

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