CN216902773U

CN216902773U - Coil skeleton, release and circuit breaker

Info

Publication number: CN216902773U
Application number: CN202220481376.9U
Authority: CN
Inventors: 张慎虎; 徐江宁; 陈鸣
Original assignee: Ningbo Gongniu Low Voltage Electric Co Ltd
Current assignee: Ningbo Gongniu Low Voltage Electric Co Ltd
Priority date: 2022-03-07
Filing date: 2022-03-07
Publication date: 2022-07-05
Anticipated expiration: 2032-03-07

Abstract

The utility model relates to the technical field of electrical equipment, in particular to a coil framework, a release and a circuit breaker; the circuit breaker comprises a release, a release contact pin, a lead wire, a winding wire, an iron core assembly and a coil framework, wherein the coil framework comprises a winding post and a mounting seat, the winding post is used for winding the winding wire, the winding post is provided with a mounting cavity, and the mounting cavity is used for assembling the iron core assembly; the mounting seat is connected with the wrapping post, and the mounting seat is provided with contact pin hole and lead wire groove, and the contact pin hole is used for setting up the contact pin, and the lead wire groove is used for the card to establish the lead wire of being connected with the contact pin. The release has stronger universality.

Description

Coil skeleton, release and circuit breaker

Technical Field

The utility model relates to the technical field of electrical equipment, in particular to a coil framework, a release and a circuit breaker.

Background

Residual current operated circuit breakers (RCBO) for domestic and similar applications, which are mainly used for earth leakage, overload and short-circuit protection, are essential items for terminal distribution circuits. Each electric leakage product is provided with an electric leakage release, when electric leakage is generated, a coil of the release generates magnetism, and the movable iron core and the ejector rod pushing mechanism are buckled, so that a circuit is cut off; the method specifically comprises the following steps: when electric leakage is generated, the mutual inductor transmits a signal to a circuit board assembly (PCBA), the coil generates a magnetic field, and the movable iron core drives the push rod to move under the action of the magnetic field, so that the push rod can push the structure connecting rod to rotate and is buckled, and a circuit is cut off.

The related art provides a trip unit generally in two forms: the tripper is of a lead type, namely is connected with a circuit board assembly (PCBA) through a lead, and the pin type is directly connected with the circuit board assembly (PCBA) through a pin, so that the tripper provided by the related technology is poor in universality.

SUMMERY OF THE UTILITY MODEL

The utility model aims to provide a coil framework, a tripper and a circuit breaker, wherein the tripper is high in universality.

The embodiment of the utility model is realized by the following steps:

in a first aspect, the present invention provides a coil bobbin comprising:

the winding post is used for winding a winding wire and provided with an installation cavity, and the installation cavity is used for assembling the iron core assembly;

the mounting seat, the mounting seat is connected with the wrapping post, and the mounting seat is provided with contact pin hole and lead wire groove, and the contact pin hole is used for setting up the contact pin, and the lead wire groove is used for the card to establish the lead wire.

In an optional embodiment, a first hole and a second hole are respectively arranged at two ends of the winding post, and both the first hole and the second hole are communicated with the mounting cavity.

In an alternative embodiment, the inner side wall of the mounting cavity is provided with a chamfer for guiding the core assembly to fit within the mounting cavity.

In a second aspect, the present invention provides a trip unit, comprising:

the bobbin of any of the previous embodiments;

the contact pin is inserted in the contact pin hole;

the lead is connected with the contact pin and clamped in the lead groove;

the winding wire is wound on the winding post and is connected with the contact pin;

and the iron core assembly is arranged in the mounting cavity.

In an alternative embodiment, the lead groove is filled with positioning glue to position the lead.

In an optional embodiment, the mounting seat is provided with two pin holes and two lead slots, the release comprises two pins and two leads, and the two pins and the two pin holes are correspondingly spliced one by one; the two lead wires are correspondingly connected with the two contact pins one by one, and the two lead wires are correspondingly clamped with the two lead wire grooves one by one.

In an optional embodiment, one end of the lead is connected with a connecting lug, the connecting lug is sleeved on the contact pin, and the connecting lug is welded with the contact pin.

In an optional embodiment, the iron core assembly comprises a movable iron core, a push rod, an elastic element and a static iron core, the movable iron core is movably arranged in the installation cavity, the static iron core is fixedly arranged in the installation cavity, the push rod is movably arranged between the movable iron core and the static iron core and can extend out of the static iron core, the movable iron core is configured to be close to the static iron core under the action of a magnetic field and push the push rod to move towards the direction extending out of the installation cavity; the elastic component is arranged between the push rod and the static iron core, and the elastic component enables the push rod and the movable iron core to move towards the direction extending into the installation cavity.

In an optional embodiment, one end of the installation cavity is provided with a second step, and when the movable iron core moves towards the direction away from the static iron core under the elastic action of the elastic piece, the movable iron core can move to abut against the second step.

In a third aspect, the present invention provides a circuit breaker including the trip unit of any one of the preceding embodiments.

The coil framework of the embodiment of the utility model has the beneficial effects that: the coil framework provided by the embodiment of the utility model comprises a winding post and a mounting seat, wherein the winding post is used for winding a winding wire, the winding post is provided with a mounting cavity, and the mounting cavity is used for assembling an iron core component; the mounting seat is connected with the wrapping post, and the mounting seat is provided with contact pin hole and lead wire groove, and the contact pin hole is used for setting up the contact pin, and the lead wire groove is used for the card to establish the lead wire. The coil skeleton can be used for the tripper, and this coil skeleton can also set up the lead wire in the lead wire groove when the contact pin hole sets up the contact pin for the tripper that has this coil skeleton can select to use the contact pin as required to be connected with the circuit board, perhaps uses the lead wire to be connected with the circuit board, even the commonality that makes the tripper that has this coil skeleton is stronger.

The release of the embodiment of the utility model has the beneficial effects that: the release provided by the embodiment of the utility model comprises a contact pin, a lead wire, a winding wire, an iron core assembly and the coil framework, wherein the contact pin is inserted in a contact pin hole; the lead is connected with the contact pin and clamped in the lead groove; winding wires are wound on the winding posts and connected with the contact pins; the iron core component is arranged in the installation cavity. Therefore, the tripper is provided with the contact pin and the lead wire simultaneously, and then the contact pin can be selected to be used to be connected with the circuit board according to needs, or the lead wire is used to be connected with the circuit board, namely the tripper has stronger universality.

The circuit breaker of the embodiment of the utility model has the beneficial effects that: the circuit breaker provided by the embodiment of the utility model comprises the tripper, the tripper can be connected with the circuit board by using the contact pin or the lead according to the requirement, and the tripper has stronger universality.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.

Fig. 1 is a partial structural schematic diagram of a circuit breaker according to an embodiment of the present invention;

fig. 2 is a schematic structural diagram of a trip unit according to an embodiment of the present invention;

FIG. 3 is a schematic diagram of a coil bobbin under a first view in an embodiment of the present invention;

FIG. 4 is a schematic structural diagram of a coil bobbin in a second view according to an embodiment of the present invention;

fig. 5 is a schematic structural diagram of a trip unit in a second view according to an embodiment of the present invention;

fig. 6 is a sectional view taken along the line a-a in fig. 5.

Icon: 010-a circuit breaker; 100-a housing; 101-a transformer; 102-a circuit board; 103-connecting rod; 200-a release; 210-a coil former; 220-wrapping post; 221-an installation cavity; 222-a first hole; 223-a second aperture; 224-chamfering; 225-limiting ribs; 226-step surface; 230-a mounting seat; 231-pin holes; 232-lead slot; 241-inserting needle; 242-wire leads; 243-engaging lug; 244-winding wire; 250-an iron core assembly; 251-a movable iron core; 252-a push rod; 253-an elastic member; 254-stationary core; 255-a through hole; 256-third aperture; 257 — fourth hole; 258-stationary core body; 259-flanging; 261-a first step; 262-a second step; 263-first core; 264-a second core; 265-backplane; 266-the pushrod body.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. The components of embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the utility model, as claimed, but is merely representative of selected embodiments of the utility model. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.

In the description of the present invention, it should be noted that the terms "inside" and "outside" are used for indicating the orientation or positional relationship based on the orientation or positional relationship shown in the drawings or the orientation or positional relationship which is usually placed when the utility model is used, and are only for convenience of describing the present invention and simplifying the description, but do not indicate or imply that the device or the element which is referred to must have a specific orientation, be constructed in a specific orientation and operation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," "third," and the like are used solely to distinguish one from another and are not to be construed as indicating or implying relative importance.

In the description of the present invention, it should also be noted that, unless otherwise explicitly specified or limited, the terms "disposed" and "connected" are to be interpreted broadly, e.g., as being either fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

The tripper provided by the embodiment can selectively use the contact pin or the lead according to the requirement, and has strong universality.

The trip unit and the circuit breaker including the trip unit will be described with reference to the accompanying drawings.

Referring to fig. 1, the present embodiment provides a circuit breaker 010, which includes a release 200, wherein the release 200 is configured to automatically open the circuit breaker 010 when an electrical leakage condition occurs.

The structure of the circuit breaker 010 is similar to that of the related art, and includes, for example: the trip device comprises a shell 100, a mutual inductor 101, a circuit board 102, a connecting rod 103, a fixed contact (not shown) and a movable contact (not shown), wherein a trip 200, the mutual inductor 101, the circuit board 102(PCBA) and the fixed contact are all fixedly arranged on the shell 100, the mutual inductor 101 and the trip 200 are all electrically connected with the circuit board 102, the connecting rod 103 is rotatably arranged on the shell 100, the movable contact is in transmission fit with the connecting rod 103, and the movable contact can be in contact with or separated from the fixed contact; when the electric leakage phenomenon occurs, the mutual inductor 101 transmits a signal to the circuit board 102, the circuit board 102 controls the tripper 200 to be electrified to generate a magnetic field, the tripper 200 pushes the connecting rod 103 to rotate under the action of the magnetic field, so that the connecting rod 103 drives the moving contact to move and separate from the fixed contact, and the circuit can be cut off.

Referring to fig. 2 and 3, the trip unit 200 of the present embodiment includes a bobbin 210, a pin 241, a lead 242, a winding wire 244, and a core assembly 250; the coil bobbin 210 comprises a winding post 220 and a mounting seat 230, the winding post 220 is used for winding a winding wire 244, the winding post 220 is provided with a mounting cavity 221, and the core assembly 250 is arranged in the mounting cavity 221; the mounting base 230 is connected with the winding post 220, and the mounting base 230 is provided with a pin hole 231 and a lead groove 232, the pin 241 is inserted into the pin hole 231, and the lead 242 is connected with the pin 241 and clamped in the lead groove 232. Therefore, the coil bobbin 210 can be simultaneously provided with the pin 241 and the lead 242, and the trip unit 200 can be selectively connected with the circuit board 102 by using the pin 241 or the lead 242 according to the requirement, i.e. the trip unit 200 has strong universality, and different trip units can be purchased and produced without additional connection modes.

Further, the mounting base 230 is provided with two pin holes 231 and two lead slots 232, the trip unit 200 includes two pins 241 and two leads 242, and the two pins 241 are correspondingly plugged with the two pin holes 231 one by one; the two leads 242 are connected to the two pins 241 in a one-to-one correspondence, and the two leads 242 are engaged with the two lead slots 232 in a one-to-one correspondence. With this arrangement, reliable connection of the circuit can be ensured regardless of whether the circuit board 102 is connected by the pin 241 or the lead 242, and thus the trip unit 200 can reliably operate.

It should be noted that the manner of fixing the pin 241 in the pin hole 231 can be selected according to the needs, for example: the pin 241 is inserted into the pin hole 231, and the pin 241 can be tightly attached to the hole wall of the pin hole 231 to form interference fit; alternatively, after the pin 241 is inserted into the pin hole 231, glue may be filled into the pin hole 231, so that the pin 241 is reliably fixed in the pin hole 231, which is not limited in this respect.

Along the axial extension direction of the winding post 220, the mounting seat 230 is fixedly connected with one end of the winding post 220; in this way, the two ends of the winding wire 244 wound around the winding post 220 can be connected and positioned with the two pins 241 respectively, and the connection method can be soldering.

It should be noted that the winding wire 244 includes, but is not limited to, an enamel wire.

In order to ensure that the lead 242 is firmly arranged on the coil bobbin 210, the lead groove 232 is filled with positioning glue to position the lead 242; when the release 200 is assembled, the plug pin 241 and the lead 242 are connected, and the lead 242 is clamped in the lead groove 232, and at the same time, glue is poured into the lead groove 232, so that the lead 242 is clamped in the lead groove 232 more firmly by the glue solidified in the lead groove 232.

It should be noted that the positioning adhesive includes, but is not limited to, epoxy resin.

The connection mode of the leads 242 and the pins 241 can be selected according to requirements; in this embodiment, one end of the lead 242 is connected to a connecting lug 243, and the connecting lug 243 is sleeved on the inserting pin 241. So configured, the ease of operation of the connection of the leads 242 to the pins 241 is ensured.

In order to ensure the reliability and stability of the connection between the lead 242 and the pin 241, the connecting lug 243 is welded to the pin 241.

When the trip unit 200 is connected to the circuit board 102(PCBA), the contact pins 241 may be selected to be connected to the circuit board 102 or the leads 242 may be selected to be connected to the circuit board 102 as required; when the lead 242 is used for connecting with the circuit board 102, one end of the lead 242 far away from the contact pin 241 is welded with the circuit board 102; when the pin 241 is used to connect the circuit board 102, the pin 241 may be directly inserted into the circuit board 102, and when the pin 241 is used to connect the circuit board 102, the lead 242 may be removed and only the pin 241 may be left in order to ensure the neatness of the assembled structure.

Referring to fig. 3 and 4, a first hole 222 and a second hole 223 are respectively formed at two ends of the winding post 220 of the present embodiment; specifically, along the axial extension direction of the winding post 220, a first hole 222 and a second hole 223 are respectively arranged at two ends of the winding post 220, and the first hole 222 and the second hole 223 are both communicated with the mounting cavity 221. Thus, when the winding wire 244 generates a magnetic field, the second hole 223 can serve as a vent hole when the core assembly 250 moves, so that air pressure at two ends of the core assembly 250 is kept balanced, excessive resistance when the core assembly 250 moves is avoided, and reliability of circuit cutting due to tripping is ensured.

Further, the second hole 223 has a smaller diameter than the first hole 222, and the core assembly 250 can be fitted into the mounting cavity 221 from the first hole 222.

Optionally, the mounting seat 230 is connected to one end of the winding post 220 provided with the second hole 223, and the second hole 223 is located below the mounting seat 230; by such an arrangement, a compact structure of the trip unit 200 is advantageously ensured, which is advantageous for a miniaturized design.

Referring to fig. 3, in order to enable the core assembly 250 to be smoothly inserted into the mounting cavity 221, the inner side wall of the mounting cavity 221 is provided with a chamfer 224 for guiding the core assembly 250 to be assembled into the mounting cavity 221, that is, when the core assembly 250 is assembled into the mounting cavity 221, the core assembly 250 can slide on a guide surface of the chamfer 224 to ensure that the core assembly 250 is smoothly inserted into the mounting cavity 221.

Further, a step surface 226 is arranged between the first hole 222 and the mounting cavity 221, the aperture of the first hole 222 is larger than the aperture of the mounting cavity 221 at the end close to the first hole 222, and a chamfer 224 is arranged adjacent to the step surface 226; thus, the assembly of the core assembly 250 can be guided by the guide surface of the chamfer 224 effectively, and the assembly can be ensured to be performed smoothly.

Referring to fig. 5 and 6, the core assembly 250 includes a movable core 251, a push rod 252, an elastic member 253, and a stationary core 254, wherein the movable core 251 is movably disposed in the installation cavity 221, the stationary core 254 is fixedly disposed in the installation cavity 221, the movable core 251 is disposed at an end close to the second hole 223, and the stationary core 254 is disposed at an end close to the first hole 222; the push rod 252 is movably arranged between the movable iron core 251 and the static iron core 254 and can extend out of the static iron core 254, specifically, the static iron core 254 is provided with a through hole 255, the push rod 252 is movably inserted into the through hole 255, and one end of the push rod 252, which is far away from the movable iron core 251, can be matched with the connecting rod 103; the movable iron core 251 is configured to approach the stationary iron core 254 under the action of the magnetic field and push the push rod 252 to move towards the direction extending out of the mounting cavity 221, that is, push the push rod 252 to move in the through hole 255, extend out of the first hole 222 and move towards the direction extending out of the mounting cavity 221; the elastic member 253 is disposed between the push rod 252 and the stationary core 254, and the elastic member 253 enables the push rod 252 and the movable core 251 to move in a direction of extending into the mounting cavity 221.

When an electric leakage condition occurs, the winding wire 244 is electrified to generate a magnetic field, the movable iron core 251 moves towards the direction close to the static iron core 254 under the action of the magnetic field to extrude the push rod 252, so that the push rod 252 penetrates through the static iron core 254 and moves towards the direction extending out of the installation cavity 221, the push rod 252 can push the connecting rod 103 to rotate, the connecting rod 103 drives the movable contact to be separated from the static contact, and a circuit can be cut off; when the leakage situation is solved, the winding wire 244 is no longer electrified to generate a magnetic field, the movable iron core 251 can move in the direction away from the static iron core 254 under the elastic action of the elastic piece 253, and the push rod 252 is driven to move in the direction extending into the installation cavity 221, so that the movable contact can be contacted with the static contact again, and the electrification is recovered; when the magnetic field is not generated in the winding wire 244, the movable iron core 251 is positioned apart from the stationary iron core 254 by the elastic member 253, and the push rod 252 does not move in a direction extending out of the mounting cavity 221, and thus the link 103 is not pushed to rotate.

It should be noted that the elastic member 253 includes, but is not limited to, a pull ring and an elastic rubber block.

In order to ensure the reliability of the static iron core 254 assembled in the installation cavity 221, the static iron core is not easy to fall out of the installation cavity 221; referring to fig. 3, the inner side wall of the installation cavity 221 is further connected with a limiting rib 225, and when the static iron core 254 is inserted into the installation cavity 221, the static iron core 254 can be tightly pressed against the limiting rib 225 to form an interference fit, so that the static iron core 254 can be reliably inserted into the installation cavity 221.

It should be noted that a chamfer 224 is provided at one end of the limiting rib 225 close to the first hole 222 to facilitate the assembly of the movable iron core 251, the push rod 252 and the stationary iron core 254.

Referring to fig. 6, the stationary core 254 includes a stationary core body 258 and a flange 259, the flange 259 is connected to an outer side wall of the stationary core body 258 and surrounds an outer periphery of the stationary core 254, when the stationary core 254 is inserted into the mounting cavity 221, the stationary core body 258 is inserted into the mounting cavity 221, and the flange 259 is overlapped on the step surface 226.

The push rod 252 includes a bottom plate 265 and a push rod body 266, the push rod body 266 is connected with the bottom plate 265, the bottom plate 265 abuts against the movable iron core 251, the push rod body 266 is movably inserted into the through hole 255, one end of the push rod body 266, which is far away from the bottom plate 265, can be matched with the connecting rod 103, the push rod body 266 is sleeved with the elastic piece 253, and two ends of the elastic piece 253 are respectively connected with the bottom plate 265 and the stationary iron core 254.

Further, through-hole 255 has been seted up to quiet iron core body 258, and through-hole 255 includes third hole 256 and the fourth hole 257 of intercommunication each other, and third hole 256 is close to movable iron core 251 and distributes, and the aperture of third hole 256 is greater than the aperture of fourth hole 257 to make and form first step portion 261 in the through-hole 255, the one end of elastic component 253 can stretch into in the third hole 256, and is connected with first step portion 261. With this arrangement, the reliability of the elastic member 253 being disposed between the push rod 252 and the stationary core 254 can be ensured.

Optionally, one end of the inner side wall of the installation cavity 221, which is close to the second hole 223, is provided with a second stepped portion 262, and the movable iron core 251 can abut against the second stepped portion 262, that is, when the movable iron core 251 moves in a direction away from the stationary iron core 254 under the elastic action of the elastic member 253, the movable iron core 251 can move to abut against the second stepped portion 262, so as to define the movement range of the movable iron core 251, and ensure the reliability of the iron core assembly 250.

Further, the plunger 251 includes a first core 263 and a second core 264 which are coaxially communicated, the diameter of the first core 263 is larger than that of the second core 264, and the first core 263 abuts against the bottom plate 265 and can abut against the second step portion 262.

The release 200 of the present embodiment can be used in a circuit breaker 010, and the release 200 can be selectively connected to the circuit board 102 by using a pin 241 or connected to the circuit board 102 by using a lead 242 as required.

In summary, the trip unit 200 of the present invention has strong versatility.

The above is only a preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes will occur to those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A coil former, comprising:

a winding post (220) for winding a winding wire (244), the winding post (220) being provided with a mounting cavity (221), the mounting cavity (221) being for assembling a core assembly (250);

the mounting seat (230), mounting seat (230) with wrapping post (220) are connected, just mounting seat (230) are provided with pin hole (231) and lead wire groove (232), pin hole (231) are used for setting up contact pin (241), lead wire groove (232) are used for the card to establish lead wire (242).

2. The bobbin according to claim 1, wherein a first hole (222) and a second hole (223) are respectively formed at both ends of the winding post (220), and the first hole (222) and the second hole (223) are both communicated with the mounting cavity (221).

3. Bobbin according to claim 1, wherein the inner side wall of the mounting cavity (221) is provided with a chamfer (224) for guiding the core assembly (250) to fit within the mounting cavity (221).

4. A trip unit, comprising:

the bobbin of any one of claims 1-3;

the contact pin (241) is inserted into the contact pin hole (231);

the lead (242) is connected with the contact pin (241) and clamped in the lead groove (232);

a winding wire (244) wound around the winding post (220) and connected to the contact pin (241);

and the iron core assembly (250) is arranged in the installation cavity (221).

5. The release of claim 4, wherein the lead slot (232) is filled with a positioning glue to position the lead (242).

6. The trip unit according to claim 4, characterized in that the mounting base (230) is provided with two pin holes (231) and two lead slots (232), the trip unit comprises two pins (241) and two leads (242), and the two pins (241) are plugged with the two pin holes (231) in a one-to-one correspondence; the two lead wires (242) are connected with the two contact pins (241) in a one-to-one correspondence manner, and the two lead wires (242) are clamped with the two lead slots (232) in a one-to-one correspondence manner.

7. The release according to claim 4, characterized in that a connecting lug (243) is connected to one end of the lead (242), and the connecting lug (243) is sleeved on the contact pin (241) and welded with the contact pin (241).

8. The trip device according to claim 4, wherein the core assembly (250) comprises a movable core (251), a push rod (252), an elastic member (253) and a stationary core (254), the movable core (251) is movably disposed in the installation cavity (221), the stationary core (254) is fixedly disposed in the installation cavity (221), the push rod (252) is movably disposed between the movable core (251) and the stationary core (254) and can extend out of the stationary core (254), the movable core (251) is configured to approach the stationary core (254) under the action of a magnetic field and push the push rod (252) to move towards the direction of extending out of the installation cavity (221); the elastic piece (253) is arranged between the push rod (252) and the static iron core (254), and the push rod (252) and the movable iron core (251) can move towards the direction extending into the mounting cavity (221) by the elastic piece (253).

9. The trip unit according to claim 8, wherein one end of the mounting cavity (221) is provided with a second step portion (262), and when the movable iron core (251) moves in a direction away from the stationary iron core (254) under the elastic force of the elastic member (253), the movable iron core (251) can move to abut against the second step portion (262).

10. A circuit breaker comprising the trip unit of any one of claims 4-9.