Release and miniature circuit breaker

Abstract

The miniature circuit breaker comprises the tripper, the tripper comprises a wiring board, a conductive board and a temperature control element, the temperature control element is heated to bend and deform to trigger an operating mechanism to trip, the wiring board comprises a wiring part and a connecting part, the wiring part is connected with one end of the connecting part, and the other end of the connecting part is connected with the conductive board. The connecting part is provided with two heating parts which are arranged at an interval, an avoiding groove is formed between the two heating parts, the two heating parts are connected with the current-conducting plate, the temperature control element comprises a fixing part, a triggering part and a supporting part, the supporting part is connected between the fixing part and the triggering part, the fixing part is connected with the connecting part, and the triggering part is connected with the supporting part. The triggering part is used for triggering the operation mechanism to release, the supporting part is provided with a heated part extending into the avoiding groove, additional elements do not need to be arranged for shunting the temperature control element, the problems of long overload time and relatively discrete overload test can be avoided, and the temperature control element and related loops do not need to be lengthened.

Description

TECHNICAL FIELD

[0001] The utility model relates to the field of low-voltage electrical apparatus, and particularly relates to a release and a miniature circuit breaker. BACKGROUND

[0002] In the low-voltage terminal circuit breaker, the overload thermal release is not easy to control the overload time of the maximum rated current specification, and the most important thing is that the overload time and the temperature rise cannot be well considered. The most commonly used first method is to shunt the temperature control element, which reduces the influence of temperature rise control on local components by reducing the heat generation of the temperature control element. However, shunting has the greatest impact on the overload test, with long and relatively dispersed overload time, greatly reducing production efficiency and qualification rate. The second method is not to shunt the temperature control element, but to lengthen the temperature control element and the related circuit. Due to the limitation of structure layout, it is easy to cause excessive heat generation and high overall temperature rise of the circuit breaker, resulting in damage to the parts. SUMMARY

[0003] The utility model aims at overcoming at least one defect of the prior art and providing a release and a circuit breaker.

[0004] To achieve the above-mentioned purpose, the utility model adopts the following technical scheme:

[0005] A release includes a terminal block, a conductive plate and a temperature control element. The temperature control element is heated and deformed to trigger the release of the operating mechanism. The terminal block includes a terminal part and a connecting part. One end of the terminal part and the connecting part is connected. The connecting part is provided with two spaced heating parts. An avoiding slot is provided between the two heating parts. The two heating parts are connected with the conductive plate respectively. The temperature control element includes a fixed part, a trigger part and a support part. The support part is connected between the fixed part and the trigger part. The fixed part is connected with the connecting part. The trigger part is used to trigger the release of the operating mechanism. The support part is provided with a heated part extending into the avoiding slot.

[0006] Preferably, the heating part includes a first heating section, a third heating section and a second heating section connected between the first heating section and the third heating section. The first heating section is connected with the conductive plate. The second heating section and the third heating section are arranged on the side of the first heating section away from the conductive plate. The connecting part and the third heating section are arranged on the same plane and are spaced apart from the conductive plate. A space for accommodating the magnetic yoke is formed between the connecting part and the conductive plate and between the third heating section and the conductive plate.

[0007] Preferably, the middle part of the heating part is bent to the side to form the second heating section, and the first heating section and the third heating section are arranged in parallel.

[0008] Preferably, the support part comprises a support section on the side of the connecting part away from the conductive plate, and a heated part connected between the support section and the triggering part, the heated part being bent towards the side of the conductive part into a avoiding slot above the connecting part.

[0009] Preferably, the heated part is bent into an arc of a semicircle, and the two ends of the heated part gap are connected with the support section and the triggering part respectively.

[0010] Preferably, the support section is arranged away from the connecting part, and the support section is connected with the fixed part through a bending section, the bending section being bent away from the side of the connecting part.

[0011] Preferably, the temperature control element is a bimetallic strip.

[0012] Preferably, the width of the fixed part of the temperature control element is greater than the width of the support part, the fixed part is provided with a first connecting hole matched with a connecting piece, the connecting part of the terminal plate is provided with a second connecting hole matched with the connecting piece, and the connecting piece connects the fixed part with the connecting part through the first connecting hole and the second connecting hole.

[0013] Preferably, it further comprises a rotatable tripping piece, and the temperature control element trips the triggering operation mechanism through the tripping piece.

[0014] Preferably, the triggering part is provided with an adjusting screw and a threaded hole matched with the adjusting screw, the triggering part drives the adjusting screw to push the tripping piece, and the adjusting screw can approach and move away from the tripping piece when it rotates relative to the triggering part.

[0015] Preferably, the tripping piece comprises two tripping side plates arranged oppositely, an overload triggering part and a short circuit triggering part connected between the two tripping side plates respectively, the connecting part of the terminal plate is located between the two tripping side plates, the terminal part of the terminal plate is located outside the tripping piece, at least one tripping side plate is provided with a tripping rod for tripping the triggering operation mechanism, the overload triggering part is located on the side of the triggering part of the temperature control element, and the short circuit triggering part is located on the side of the armature.

[0016] Preferably, the two tripping side plates are provided with rotating shafts as rotating centers, a support rod is arranged between the two tripping side plates, the support rod and the tripping rod are arranged on the two sides of the rotating shaft in the radial direction, and the support rod is connected between the two tripping side plates.

[0017] The disconnector of the utility model, the wiring board reduces the cross-sectional area of current passing through by two interval heating parts, improves the heating efficiency of the heating part, and sets the protruding heated part on the temperature control element into the two heating parts, heats the heated part by the two heating parts, does not need to set additional elements to shunt the temperature control element, can avoid the problems of long overload time and relatively discrete for the overload test, and further improves the yield, and does not need to lengthen the temperature control element and related circuit, can avoid the problems of large volume and excessively high temperature rise.

[0018] In addition, by adjusting the width a, thickness b and length c of the heating part, the cross-sectional size of the current passing through can be changed, and the heating efficiency of the heating part is further adjusted.

[0019] In addition, only the area corresponding to the heated part and the two side heating parts can be changed, the efficiency of the heating part heating the heated part is adjusted, and the length L of the temperature control element can also be changed to adjust the temperature control element.

[0020] The embodiment also provides a miniature circuit breaker, which comprises a shell and a moving contact, a static contact, an operating mechanism, an arc extinguishing chamber, two wiring terminals and the disconnector arranged in the shell respectively.

[0021] Preferably, the shell is in the shape of a convex character, the operating mechanism is arranged between the two wiring terminals, the disconnector and the arc extinguishing chamber are arranged on the two sides of the operating mechanism in the length direction of the miniature circuit breaker, the disconnector and the disconnector part are located between the operating mechanism and the wiring terminal corresponding to the moving contact, the arc extinguishing chamber is located between the operating mechanism and the wiring terminal corresponding to the static contact, one end of the moving contact is connected with the operating mechanism, the end of the moving contact away from the operating mechanism extends to between the operating mechanism and the arc extinguishing chamber, and the static contact is arranged between the operating mechanism and the arc extinguishing chamber.

[0022] Preferably, the disconnector part is provided with a rotating shaft rotatably connected with the shell, the rotating shaft is arranged corresponding to the gap between the magnetic yoke and the conductive plate, the conductive plate is located on the side of the rotating shaft close to the operating mechanism, the magnetic yoke is located on the side of the rotating shaft away from the operating mechanism, the wiring board and the temperature control element are arranged on the side of the magnetic yoke away from the rotating shaft, the armature is arranged on the side of the temperature control element away from the rotating shaft, and the tension spring is arranged on the side of the armature away from the temperature control element and connected between the armature and the shell.

[0023] The miniature circuit breaker of the utility model can improve the yield of the miniature circuit breaker on the basis of the advantages of the disconnector, can avoid the problem that the overheating of the disconnector affects other parts, improves the stability of the miniature circuit breaker, and prolongs the service life of the miniature circuit breaker. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 is the structural schematic view of the miniature circuit breaker of the utility model;

[0025] Figure 2 Figure is the cooperation schematic view of the wiring board, the conductive plate, the temperature control element and the magnetic yoke of the utility model;

[0026] Figure 3 Figure is the structure schematic view of the wiring board of the utility model;

[0027] Figure 4 Figure is the structure schematic view of the temperature control element of the utility model;

[0028] Figure 5 Figure is the structure schematic view of the release of the utility model;

[0029] In the figure:

[0030] 1 shell

[0031] 2 wiring board

[0032] 3 conductive plate

[0033] 4 temperature control element

[0034] 5 release

[0035] 7 connecting piece

[0036] 8 adjusting screw

[0037] 12 moving contact

[0038] 13 static contact

[0039] 14 operating mechanism

[0040] 15 arc extinguishing chamber

[0041] 16 terminal

[0042] 17 handle

[0043] 18 installation groove

[0044] 21 wiring part

[0045] 22 connecting part

[0046] 23 heating part

[0047] 24 avoiding groove

[0048] 41 fixed part

[0049] 42 triggering part

[0050] 43 supporting part

[0051] 44 heated part

[0052] 45 supporting section

[0053] 46 curved segment

[0054] 51 tripping side plate

[0055] 52 overload trigger part

[0056] 53 short-circuit trigger part

[0057] 54 support rod

[0058] 55 rotating shaft

[0059] 56 tripping rod

[0060] 61 magnetic yoke

[0061] 62 armature

[0062] 63 tension spring

[0063] 71 first connecting hole

[0064] 72 second connecting hole

[0065] 81 threaded hole

[0066] 231 first heating segment

[0067] 232 second heating segment

[0068] 233 third heating segment

[0069] 611 first side plate

[0070] 612 second side plate

[0071] 613 support plate

[0072] 621 swinging part

[0073] 622 mounting part

[0074] 623 hitting part

[0075] 624 mounting shaft DETAILED DESCRIPTION

[0076] The specific embodiments of the tripping device of the present application are further illustrated in the following examples in conjunction with the accompanying drawings. The tripping device of the present application is not limited to the description of the following examples.

[0077] As Figure 1As shown, this embodiment provides a miniature circuit breaker, including a housing 1 and a moving contact 12, a stationary contact 13, an operating mechanism 14, an arc-extinguishing chamber 15, two terminals 16, and a trip unit respectively disposed in the housing 1. The housing 1 is approximately U-shaped, with a raised structure in the middle of the top side of the housing 1, in which a handle 17 is provided. A mounting groove 18 is provided in the middle of the bottom side of the housing 1, and the groove wall of the mounting groove is provided with a mounting structure for mounting with a distribution box rail. The two terminals 16 are disposed at the left and right ends of the housing 1, and are respectively disposed corresponding to the moving contact 12 and the stationary contact 13. Contact 12 and stationary contact 13 are respectively connected to two terminals 16 and connected to the circuit. The operating mechanism 14 is connected to a handle 17, which extends to the outside of the housing 1 for user operation. Rotating the handle 17 can cause the moving contact 12 to contact and separate from the stationary contact 13 through the operating mechanism 14, thereby connecting and disconnecting the circuit. When a fault current occurs in the circuit, the trip unit triggers the operating mechanism 14 to trip, causing the operating mechanism 14 to separate the moving contact 12 from the stationary contact 13, disconnecting the circuit and achieving the protection function. In this embodiment, the trip unit is a thermal-magnetic trip unit, which has overload protection and short-circuit protection functions. Of course, the trip unit may also only have one of the overload protection and short-circuit protection functions, and the circuit breaker can be equipped with overload trip units and short-circuit trip units respectively.

[0078] like Figures 2-4 As shown, a trip unit in this embodiment includes a terminal block 2, a conductive plate 3, and a temperature control element 4. The moving contact 12 is connected to the corresponding terminal block 16 via the conductive plate 3 and the terminal block 2. When an overload current passes through, the terminal block 2 can heat the temperature control element 4. The temperature control element 4 bends and deforms due to heat, which can trigger the operating mechanism 14 to trip.

[0079] The terminal block 2 comprises a vertically arranged terminal part 21 connected with the terminal 16 and a connecting part 22, one end of the terminal part 21 and the connecting part 22 is connected, and two spaced heating parts 23 are arranged on the end of the connecting part 22 away from the terminal part 21, a avoiding slot 24 is arranged between the two heating parts 23, the two heating parts 23 are respectively connected with the conductive plate 3, the conductive plate 3 is connected with the movable contact 12 through a wire, the temperature control element 4 comprises a fixed part 41, a triggering part 42 and a supporting part 43, the supporting part 43 is connected between the fixed part 41 and the triggering part 42, the fixed part 41 is connected with the side of the connecting part 22, the triggering part 42 is used for triggering the operating mechanism 14 to trip directly or indirectly, the supporting part 43 is provided with a heated part 44 extending into the avoiding slot 24, the two heating parts 23 respectively heat the heated part 44 from opposite sides, so that the temperature control element 4 is bent and drives the triggering part 42 to move, and when the temperature control element 4 rises to a threshold value, the bending deformation can make the triggering part 42 trigger the operating mechanism 14 to trip. In the embodiment, the conductive plate 3 is electrically connected with the movable contact 12, and as other embodiments, it can also be electrically connected with the static contact 13.

[0080] The tripping device of the embodiment, the terminal block 2 narrows the cross-sectional area of the current through the two spaced heating parts 23, improves the heating efficiency of the heating part 23, and sets the protruding heated part 44 of the temperature control element 4 between the two heating parts 23, and heats the heated part 44 by the two heating parts 23, without setting additional elements to shunt the temperature control element 4, which can avoid the problems of long overload time and relatively discrete for the overload test, thereby improving the yield, and without the need to lengthen the temperature control element 4 and the related circuit, which can avoid the problems of large volume and high temperature rise.

[0081] The micro circuit breaker of the embodiment, on the basis of the advantages of the tripping device, can improve the yield of the micro circuit breaker, avoid the influence of the tripping device overheating on other parts, improve the stability of the micro circuit breaker, and prolong the service life of the micro circuit breaker.

[0082] As shown in Figure 5 The tripping device of the embodiment also has a short circuit protection function, which comprises a magnetic yoke 61 and an armature 62 rotatably arranged on the magnetic yoke 61, the connecting part 22 of the terminal block 2 passes between the magnetic yoke 61 and the armature 62, when the short circuit current flows through the terminal block 2, the magnetic yoke 61 can attract the armature 62 to rotate, and trigger the operating mechanism 14 to trip through the armature 62. In the embodiment, the magnetic yoke 61 is fixedly connected with the connecting part 22.

[0083] The housing 1 is provided with a rotating tripping piece 5, the tripping piece 5 comprises two tripping side plates 51 arranged oppositely, and an overload trigger 52, a short-circuit trigger 53 and a support rod 54 vertically connected between the two tripping side plates 51 respectively, the support rod 54 serves to connect the two tripping side plates 51, the connecting part 22 of the terminal plate 2 is located between the two tripping side plates 51, the wiring part 21 of the terminal plate 2 is located outside the tripping piece 5, the two tripping side plates 51 are respectively provided with a rotating shaft 55 rotatably connected with the housing 1, at least one tripping side plate 51 is provided with a tripping rod 56 protruding in the radial direction of the rotating shaft 55, the tripping rod 56 is used to trigger the operation mechanism 14 to trip, the support rod 54 and the tripping rod 56 are arranged on the two sides of the rotating shaft 55 in the radial direction, the overload trigger 52 is located on the side of the trigger part 42 of the temperature control element 4, the trigger part 42 can push the overload trigger 52, so that the tripping piece 5 rotates and drives the tripping rod 56 to trigger the operation mechanism 14 to trip, the short-circuit trigger 53 is located on the side of the armature 62, the armature 62 is located between the support rod 54 and the short-circuit trigger 53, the armature 62 can push the short-circuit trigger 53, so that the tripping piece 5 rotates and drives the trigger rod to trigger the operation mechanism 14 to trip. In other embodiments, the support rod 54 can also be arranged as the short-circuit trigger 53, for example, the bottom of the armature 62 strikes the support rod 54, so that the support rod 54 drives the armature 62 to rotate, which all belong to the protection scope of the utility model.

[0084] Further, the operation mechanism 14 is arranged between the two terminal posts 16, the tripper and the arc extinguishing chamber 15 are arranged on the two sides of the operation mechanism 14 in the length direction of the miniature circuit breaker, the tripper and the tripping piece 5 are located between the operation mechanism 14 and the terminal post 16 where the corresponding movable contact 12 is arranged, the arc extinguishing chamber 15 is located between the operation mechanism 14 and the terminal post 16 where the corresponding fixed contact 13 is arranged, one end of the movable contact 12 is connected with the operation mechanism 14, the end of the movable contact 12 away from the operation mechanism 14 extends to between the operation mechanism 14 and the arc extinguishing chamber 15, and the fixed contact 13 is arranged between the operation mechanism 14 and the arc extinguishing chamber 15.

[0085] Further, the rotating shaft 55 of the tripping piece 5 corresponds to the gap between the magnetic yoke 61 and the conductive plate 3, the conductive plate 3 is located on the side of the rotating shaft 55 close to the operation mechanism 14, the magnetic yoke 61 is located on the side of the rotating shaft 55 away from the operation mechanism 14, the terminal plate 2 and the temperature control element 4 are arranged on the side of the magnetic yoke 61 away from the rotating shaft 55, the armature 62 is arranged on the side of the temperature control element 4 away from the rotating shaft 55, and the tension spring 63 is arranged on the side of the armature 62 away from the temperature control element 4, the tension spring 63 is connected between the armature 62 and the housing 1, and is used to drive the armature 62 to rotate and reset.

[0086] As Figures 2-3As shown, the width of the connecting portion 22 of the terminal block 2 is smaller than the width of the terminal block 21. Heating portions 23 are respectively provided at the two apex corners of the connecting portion 22 away from the terminal block 21. The heating portion 23 includes a first heating section 231 and a third heating section 233, and a second heating section 232 connected between the first heating section 231 and the third heating section 233. The first heating section 231 is welded to the conductive plate 3. The second heating section 232 and the third heating section 233 are located on the side of the first heating section 231 away from the conductive plate 3. The connecting portion 22 and the third heating section 233 are arranged on the same plane and spaced apart from the conductive plate 3. A space for accommodating the magnetic yoke 61 is formed between the connecting portion 22 and the conductive plate 3, and between the third heating section 233 and the conductive plate 3.

[0087] In this embodiment, the middle portion of the heating section 23 is bent laterally to form the second heating segment 232, and the first heating segment 231 and the third heating segment 233 are arranged in parallel. Alternatively, the heating section 23 can also adopt other shapes, such as having multiple bent second heating segments 232, or having the second heating segment 232 directly connected to the connecting portion 22 without the third heating segment 233. Furthermore, the heating section 23 may not have bent second heating segments 232; instead, the conductive plate 3 may be bent laterally and have a structure to avoid the temperature control element 4. The heating section 23 may be planar, creating spaces between the connecting portion 22 and the conductive plate 3, and between the third heating segment 233 and the conductive plate 3, to accommodate the magnetic yoke 61. It is understood that by adjusting the width a, thickness b, and length c of the heating section 23, the cross-sectional area through which the current passes can be changed, thereby adjusting the heating efficiency of the heating section 23.

[0088] like Figure 4 As shown, the temperature control element 4 in this embodiment is a bimetallic strip. The bimetallic strip will bend to the side when heated. The width of the fixing part 41 of the temperature control element 4 is greater than the width of the supporting part 43. The fixing part 41 is provided with a first connecting hole 71 that cooperates with the connector 7. The connecting part 22 of the terminal block 2 is provided with a second connecting hole 72 that cooperates with the connector 7. The connector 7 passes through the first connecting hole 71 and the second connecting hole 72 to connect the fixing part 41 and the connecting part 22. The connector 7 can be a screw, a rivet, or can connect the temperature control element 4 and the terminal block 2 through other connection methods.

[0089] The trigger part 42 is provided with an adjusting screw 8 and a threaded hole 81 that cooperates with the adjusting screw 8. The trigger part 42 drives the adjusting screw 8 to push the tripping member 5. When the adjusting screw 8 rotates relative to the trigger part 42, the adjusting screw 8 moves radially under the action of the threaded hole 81, which can change the distance between the adjusting screw 8 and the tripping member 5, thereby changing the stroke of the temperature control element 4. The threshold value can be adjusted when the overload current trips.

[0090] Further, the support part 43 comprises a support section 45 located at the side of the connecting part 22 away from the conductive plate 3, and a heated part 44 connected between the support section 45 and the triggering part 42, the heated part 44 is bent to the side close to the conductive part into the avoiding groove 24 above the connecting part 22.

[0091] The heated part 44 of the embodiment is an incomplete annular with a notch, the heated part 44 can also be an arc shape bent to approximate a semicircle, the two ends of the notch of the heated part 44 are connected with the support section 45 and the triggering part 42 respectively, the size of the heated part 44 can be changed by changing the radius R of the heated part 44, not only the area of the heated part 44 corresponding to the two sides of the heating part 23 can be changed, the efficiency of the heating part 23 heating the heated part 44 can be adjusted, but also the length L of the temperature control element 4 can be changed, the adjustment of the temperature control element 4 can be realized, the heated part 44 can also adopt an S-shaped or other shape after multiple bending.

[0092] In addition, the heated part 44 can also not be bent, for example, a flat plate type heated part 44 is adopted, the heated part 44 is inclined and connected between the triggering part 42 and the support part 43, the heated part 44, the triggering part 42 and the support part 43 form a Z-shaped structure, all of which belong to the protection scope of the utility model.

[0093] Further, the support section 45 is arranged apart from the connecting part 22, the support section 45 is connected with the fixed part 41 through a bending section 46, the bending section 46 is bent to the side away from the connecting part 22, when the temperature control element 4 is heated and bent, a space for avoiding the temperature control element 4 is formed between the support section 45 and the connecting part 22.

[0094] As shown in Figure 2 The magnetic yoke 61 comprises two first side plates 611 arranged oppositely, and a second side plate 612 connected between the two first side plates 611, the second side plate 612 is arranged between the connecting part 22 and the conductive plate 3, and the second side plate 612 is below the heating part 23, the connecting part 22 of the wiring plate 2 and the support part 43 of the temperature control element 4 are located between the two first side plates 611,

[0095] Support plates 613 are arranged on the two first side plates 611 away from the second side plate 612, mounting holes are arranged on the support plates 613,

[0096] The armature 62 comprises a swing part 621 in the shape of a flat plate, and a mounting part 622 and a striking part 623 arranged oppositely at the two ends of the swing part 621, the mounting part 622 is in the shape of a U and is located between the two support plates 613, the mounting part 622 is rotationally connected with the two support plates 613 through a mounting shaft 624, the striking part 623 is inclined to the side of the swing part 621 away from the temperature control element 4, when the armature 62 rotates, the short-circuit triggering part 53 is pushed by the striking part 623, and the trip operation mechanism 14 is tripped by the trip member 5.

[0097] It should be noted that in the description of the utility model, the terms "upper", "lower", "left", "right", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings or the orientation or positional relationship when used, and are only for the convenience of description, and do not indicate that the device or element referred to must have a particular orientation, and therefore cannot be understood as a limitation on the utility model. In addition, the terms "first", "second", "third" and the like are only used for differentiation in description, and cannot be understood as indicating relative importance.

[0098] The above is a further detailed description of the utility model in combination with specific preferred embodiments, and the specific implementation of the utility model cannot be limited to these descriptions. For ordinary skilled persons in the technical field to which the utility model belongs, without departing from the concept of the utility model, a number of simple deductions or substitutions can also be made, and all should be regarded as falling within the protection scope of the utility model.

Claims

1. A release comprising a terminal plate (2), a conducting plate (3) and a temperature control element (4), the temperature control element (4) being heat-bent deformed for triggering a release of an operating mechanism (14), the terminal plate (2) comprising a terminal portion (21) and a connecting portion (22), the terminal portion (21) and the connecting portion (22) being connected at one end, characterized in that: The connecting part (22) is provided with two spaced heating parts (23), and a avoiding slot (24) is arranged between the two heating parts (23), the two heating parts (23) are connected with the conductive plate (3) respectively, the temperature control element (4) comprises a fixed part (41), a triggering part (42) and a supporting part (43), the supporting part (43) is connected between the fixed part (41) and the triggering part (42), the fixed part (41) is connected with the connecting part (22), the triggering part (42) is used for triggering the operating mechanism (14) to trip, and the supporting part (43) is provided with a heated part (44) extending into the avoiding slot (24).

2. The trip unit of claim 1, wherein: The heating part (23) comprises a first heating section (231) and a third heating section (233), and a second heating section (232) connected between the first heating section (231) and the third heating section (233), the first heating section (231) is connected with the conductive plate (3), the second heating section (232) and the third heating section (233) are arranged on the side of the first heating section (231) away from the conductive plate (3), the connecting part (22) is arranged in the same plane with the third heating section (233) and is spaced from the conductive plate (3), and a space for accommodating the magnetic yoke (61) is formed between the connecting part (22) and the conductive plate (3) and between the third heating section (233) and the conductive plate (3).

3. The trip unit of claim 2, wherein: The middle part of the heating part (23) is bent to the side to form the second heating section (232), and the first heating section (231) and the third heating section (233) are arranged in parallel.

4. The trip unit of claim 1, wherein: The supporting part (43) comprises a supporting section (45) located on the side of the connecting part (22) away from the conductive plate (3), and a heated part (44) connected between the supporting section (45) and the triggering part (42), the heated part (44) is bent to the side close to the conductive part into the avoiding slot (24) above the connecting part (22).

5. The trip unit of claim 4, wherein: The heated part (44) is bent into a semicircular arc, and the two ends of the heated part (44) are connected with the supporting section (45) and the triggering part (42) respectively.

6. The trip unit of claim 4, wherein: The supporting section (45) is spaced from the connecting part (22), the supporting section (45) is connected with the fixed part (41) through a bending section (46), and the bending section (46) is bent to the side away from the connecting part (22).

7. The trip unit of claim 1, wherein: The temperature control element (4) is a bimetallic strip.

8. The trip unit of claim 1, wherein: The width of the fixed part (41) of the temperature control element (4) is greater than the width of the supporting part (43), the fixed part (41) is provided with a first connecting hole (71) matched with the connecting piece (7), the connecting part (22) of the wiring board (2) is provided with a second connecting hole (72) matched with the connecting piece (7), and the connecting piece (7) passes through the first connecting hole (71) and the second connecting hole (72) to connect the fixed part (41) with the connecting part (22).

9. The trip unit of claim 1, wherein: Further comprising a rotatable tripping piece (5), and the temperature control element (4) triggers the operating mechanism (14) to trip through the tripping piece (5).

10. The trip unit of claim 9, wherein: The trigger part (42) is provided with an adjusting screw (8) and a threaded hole (81) matched with the adjusting screw (8), the trigger part (42) drives the adjusting screw (8) to push the tripping part (5), and the adjusting screw (8) can approach and move away from the tripping part (5) when rotating relative to the trigger part (42).

11. The trip unit of claim 9, wherein: The tripping part (5) comprises two tripping side plates (51) oppositely arranged, an overload trigger part (52) and a short-circuit trigger part (53) respectively connected between the two tripping side plates (51), the connecting part (22) of the terminal block (2) is located between the two tripping side plates (51), the terminal part (21) of the terminal block (2) is located outside the tripping part (5), at least one tripping side plate (51) is provided with a tripping rod (56) for triggering the operation mechanism (14) to trip, the overload trigger part (52) is located on the side of the trigger part (42) of the temperature control element (4), and the short-circuit trigger part (53) is located on the side of the armature (62).

12. The trip unit of claim 11, wherein: The two tripping side plates (51) are provided with a rotating shaft (55) as a rotating center, and a supporting rod (54) is arranged between the two tripping side plates (51), the supporting rod (54) is arranged on the two sides of the rotating shaft (55) in the radial direction and is opposite to the tripping rod (56), and the supporting rod (54) is connected between the two tripping side plates (51).

13. A miniature circuit breaker characterized by: The micro circuit breaker comprises a shell (1), a movable contact (12), a stationary contact (13), an operation mechanism (14), an arc extinguishing chamber (15), two terminal blocks (16) and the tripping device according to any one of claims 1-12.

14. The miniature circuit breaker of claim 13, wherein: The shell (1) is in the shape of a convex letter, the operation mechanism (14) is arranged between the two terminal blocks (16), the tripping device and the arc extinguishing chamber (15) are arranged on the two sides of the operation mechanism (14) in the length direction of the micro circuit breaker, the tripping device and the tripping part (5) are located between the operation mechanism (14) and the terminal block (16) corresponding to the movable contact (12), the arc extinguishing chamber (15) is located between the operation mechanism (14) and the terminal block (16) corresponding to the stationary contact (13), one end of the movable contact (12) is connected with the operation mechanism (14), the other end of the movable contact (12) away from the operation mechanism (14) extends to the space between the operation mechanism (14) and the arc extinguishing chamber (15), and the stationary contact (13) is arranged between the operation mechanism (14) and the arc extinguishing chamber (15).

15. The miniature circuit breaker of claim 14, wherein: The tripping device (5) is provided with a rotating shaft (55) rotatably connected with the shell (1), the rotating shaft (55) is arranged corresponding to the gap between the magnetic yoke (61) and the conductive plate (3), the conductive plate (3) is located on the side of the rotating shaft (55) close to the operating mechanism (14), the magnetic yoke (61) is located on the side of the rotating shaft (55) away from the operating mechanism (14), the wiring board (2) and the temperature control element (4) are arranged on the side of the magnetic yoke (61) away from the rotating shaft (55), the armature (62) is arranged on the side of the temperature control element (4) away from the rotating shaft (55), and the tension spring (63) is arranged on the side of the armature (62) away from the temperature control element (4), wherein the tension spring (63) is connected between the armature (62) and the shell (1).

Images