CN207852598U - A kind of miniature circuit breaker - Google Patents

Abstract

The utility model discloses a kind of miniature circuit breaker, including shell, operating mechanism, contact mechanism and the overload protecting mechanism being installed in the shell, the overload protecting mechanism include bimetal leaf and heat-conducting piece and driving member；One end of the heat-conducting piece is connect with moving contact, and the other end is connect with outlet side terminal, and the galvanic circle that outlet side terminal is transferred to through moving contact and heat-conducting piece, the bimetal leaf and the heat-conducting piece thermal conductive contact are formed when moving contact closes a floodgate with static contact.Using technical solutions of the utility model, heat-conducting piece generates heat when passing through electric current, to carry out auxiliary heating to bimetal leaf, the heat-conducting piece resistivity is less than the resistivity of the bimetal leaf to promote the conductive capability of heat-conducting piece, without the design method of two-way electric current, realize miniature circuit breaker meet more high current by design requirement, stability is more preferable, simple and more acurrate, reduction design difficulty is debugged, it is highly practical.

Description

A kind of miniature circuit breaker

Technical field

The utility model is related to low voltage electrical apparatus technology fields, and in particular to a kind of miniature circuit breaker.

Background technology

There is miniature circuit breaker two big major protective function of short-circuit protection and overload protection, overload protection to pass through breaker Thermal tripping system realizes protection.When circuit overloads, it is more than as defined in miniature circuit breaker by the electric current of miniature circuit breaker When rated current, the calorific value of miniature circuit breaker increases, and so that the bimetal leaf in thermal tripping system is heated by circuit loop swollen Swollen bending pushes the trip assembley therefor in miniature circuit breaker to act the tripping so that breaker using one end bending of double gold, from And realize the overload protection to circuit and electrical equipment.

But in existing miniature circuit breaker, bimetal leaf can not bear the logical of high current because of the limitation of production technology It crosses, can only generally bear 63A and following electric current passes through.If the cross-sectional dimensions of bimetal leaf are done greatly, it is easy to influence itself It is not flexible using characteristic, it is fragile, to also limit the development that miniature circuit breaker promotes high current ability, such pole Improve design difficulty greatly.

For this purpose, occurring in the prior art in tripping system by the way of current distributing so that breaker passes through bigger Electric current, as Chinese patent literature CN203707061U discloses a kind of miniature circuit breaker, including shell, electromagnetic system, contact system System and arc quenching system, outgoing line side current path connect from the moving contact in contact system through the first conducting wire, bimetal leaf, heating element Further include the second conducting wire of the welding section that one end is connected to moving contact back, the second conducting wire other end to leading-out terminal connecting terminal Be connected to heating element, heating element is welded by welded plate and leading-out terminal connecting terminal, therefore, from moving contact by electric current point Leading-out terminal connecting terminal is not connected with bimetal leaf by the first conducting wire and the heated element of the second conducting wire.

Although the structure setting of above patent document can be such that current class is promoted to 80A, in actual use from 63A There are still problems with：Using the form of two-way current distributing, two accesses are affected by spot-welding technology, when solder joint unevenness When so that the resistivity of a line conductor is lower, become larger by electric current, distributed so as to cause two-way electric current uneven so that miniature circuit breaker It is failure to actuate within the thermal tripping time or acts too early, deflect away from claimed range, debugging difficulty increases, and stability is poor, influences product Performance.Secondly, shunting improves bimetal leaf tolerance electric current limited by the two Resistance Influence.

Utility model content

Therefore, the technical problem to be solved by the present invention is to overcome miniature circuit breaker in the prior art that can not bear High current is big by the two Resistance Influence by and using two-way current distributing, and to cause the distribution of two-way electric current uneven, debugging is difficult Degree is big, the problem of stability difference, to provide it is a kind of it is simple in structure, debugging facilitates, stability is good, high current can be born by Miniature circuit breaker.

In order to solve the above technical problems, the utility model provides a kind of miniature circuit breaker, including shell, it is installed on the shell Internal operating mechanism, contact mechanism and overload protecting mechanism, the operating mechanism drive the moving contact in the contact mechanism It contacts and closes a floodgate with static contact, alternatively, driving the moving contact with the static contact far from separating brake；

The overload protecting mechanism includes bimetal leaf and heat-conducting piece, and, trigger institute under bimetal leaf effect State the driving member that operating mechanism drives the contact mechanism separating brake；One end of the heat-conducting piece is connect with the moving contact, another End is connect with outlet side terminal, is formed through the moving contact and the heat-conducting piece when moving contact closes a floodgate with the static contact It is transferred to the galvanic circle of the outlet side terminal, the bimetal leaf and the heat-conducting piece thermal conductive contact；The heat-conducting piece Resistivity is less than the resistivity of the bimetal leaf.

As a preferred embodiment, the heat-conducting piece is the laminated structure extended side by side with the bimetal leaf, described double Sheet metal fits in the heat-conducting piece side.

As a preferred embodiment, the bimetal leaf by adhesive glue sticker in the heat-conducting piece backwards to the moving contact Side.

As a preferred embodiment, one end of the bimetal leaf is the fixing end with the heat-conducting piece secure fit, separately One end is the free end of heated bending；The free end is connected with the driving member, and the operation is triggered by the driving member Mechanism drives the contact mechanism separating brake.

As a preferred embodiment, the fixing end is concordant with the heat-conducting piece end, and the two is fixedly installed in the shell Clip position on body, the free end exceed the heat-conducting piece setpoint distance.

As a preferred embodiment, determining for bimetal leaf described in fixed clamp and the heat-conducting piece is provided on the shell Position adjusting part, the positioning adjusting part includes the positioning plate being installed in the shell, and is removably set on the shell Adjusting screw in body formed pilot hole, the positioning plate and the adjusting screw formed in opposite directions the clamping bimetal leaf and The clip position of heat-conducting piece, by rotating adjusting screw for finely tuning opposite position of the bimetal leaf in the shell It sets.

As a preferred embodiment, the both ends side of the heat-conducting piece has been separately formed gusset piece and second line of a couplet fishplate bar, institute It states gusset piece by soft strength to be connected with the moving contact, the second line of a couplet fishplate bar is connect with the outlet side terminal.

As a preferred embodiment, the heat-conducting piece is by T1 red copper integrally casting shapings.

As a preferred embodiment, the operating mechanism includes：

Operation handle；

Contact supporting is rotatably provided in the shell；The moving contact be mounted on the contact supporting on and with institute State contact supporting linkage setting；

Resetting spring, one end are connected to the shell, and the other end is connected to the contact supporting, and the resetting spring is to institute It states contact supporting and applies the active force for driving the moving contact trend to be detached with the static contact；

Tripping is rotatably provided in the contact supporting, links with the operation handle；

Lock, is pivotally mounted to the contact supporting, when coordinating with the tripping, the contact supporting is in the operation The handle effect lower driving moving contact movement；It is detached from and coordinates with the tripping, the contact supporting is in the resetting spring Effect is lower to drive the moving contact far from the static contact；

The bimetal leaf drives the lock to be detached from the cooperation with the tripping by the driving member.

As a preferred embodiment, the driving member is pull rod, and one end of the pull rod is fixed on the lock, another It holds and extends to the bimetal leaf side and be oppositely arranged with the free end.

The technical solution of the utility model has the following advantages that：

1. in miniature circuit breaker provided by the utility model, overload protecting mechanism includes the bimetal leaf of thermal conductive contact and leads Warmware, one end of heat-conducting piece are connect with the moving contact, and the other end is connect with outlet side terminal, this structure setting, by moving Contact, heat-conducting piece and outlet side terminal constitute galvanic circle, and the heat-conducting piece generates heat when passing through electric current, to bimetallic Piece carries out auxiliary heating, power circuit will not be constituted since bimetal leaf does not connect load, to overcome bimetal leaf by electric current Therefore the problem of limitation, when bimetal leaf is heated reaches overload temperature, flexure operation and can pass through driving member driving behaviour naturally Make mechanism and carries out sub-switching operation, i.e., dynamic and static contact separation.Using technical solution of the present invention, the heat-conducting piece resistivity is less than double The resistivity of sheet metal has fabulous electric conductivity, thermal conductivity and processing performance, promotes the conductive capability of heat-conducting piece, technology people Member can accordingly select the specification of heat-conducting piece according to the design specification of miniature circuit breaker, neither change bimetal leaf, again Can avoid using two-way electric current design method, with galvanic circle all the way realize miniature circuit breaker meet more high current by set Meter demand, stability is more preferable, and debugging is simple and more acurrate, reduces design difficulty, miniature circuit breaker is made to be truly realized more than 63A's High current specification, it is highly practical, it is widely used.

2. in miniature circuit breaker provided by the utility model, the positioning adjusting part includes being installed in the shell Positioning plate, and the adjusting screw that is removably set in the molding pilot hole of the shell, the positioning plate and the adjusting spiral shell One end of the bimetal leaf and heat-conducting piece is clamped in silk in opposite directions, to play fixed work in shell to bimetal leaf and heat-conducting piece With from above-mentioned set-up mode, it is only necessary to by rotating the stroke distances of the adjusting screw, to consolidate to bimetal leaf Positioning, which is set, to be finely adjusted, and the purpose for adjusting distance between bimetal leaf and driving member is played, so that bimetal leaf overload bending Apart from shorter, triggering is more timely for driving, and cooperation is accurate and reliable, easy to adjust.

3. in miniature circuit breaker provided by the utility model, one end of the pull rod is fixed on the lock, the other end Extend to the bimetal leaf side and be oppositely arranged with the free end, bimetal leaf bending in overload pushes described The other end of pull rod drives the lock to rotate and releases the lock fit with the tripping, i.e., the described lock by the pull rod Rotation is generated under the pulling force effect of the pull rod, to release the matching relationship of lock and tripping, to reach the heat of breaker The purpose of dropout protection, securely and reliably.

Description of the drawings

It, below will be right in order to illustrate more clearly of specific embodiment of the present invention or technical solution in the prior art Specific implementation mode or attached drawing needed to be used in the description of the prior art are briefly described, it should be apparent that, it is described below In attached drawing be that some embodiments of the utility model are not paying creativeness for those of ordinary skill in the art Under the premise of labour, other drawings may also be obtained based on these drawings.

Fig. 1 is the planar structure schematic diagram of miniature circuit breaker provided by the utility model；

Fig. 2 is the dimensional structure diagram of the miniature circuit breaker of the utility model；

Fig. 3 is the dimensional structure diagram of the other side of the miniature circuit breaker of the utility model；

Fig. 4 is the structural schematic diagram of the heat-conducting piece and bimetal leaf of the utility model；

Reference sign：1- shells, 2- operating mechanisms, 21- contact supportings, 22- trippings, 23- locks, 24- reset bullet Spring, 3- moving contacts, 4- static contacts, 51- bimetal leafs, 52- heat-conducting pieces, the upper gusset pieces of 521-, 522- second line of a couplet fishplate bars, 53- positioning Plate, 54- adjusting screws, 55- driving members, 6- outlet side terminals.

Specific implementation mode

The technical solution of the utility model is clearly and completely described below in conjunction with attached drawing, it is clear that described Embodiment is the utility model a part of the embodiment, instead of all the embodiments.Based on the embodiments of the present invention, originally The every other embodiment that field those of ordinary skill is obtained without making creative work, belongs to this practicality Novel protected range.

In the description of the present invention, it should be noted that term " first ", " second ", " third " are only used for describing Purpose is not understood to indicate or imply relative importance.

In the description of the present invention, it should be noted that unless otherwise clearly defined and limited, term " is pacified Dress ", " connected ", " connection " shall be understood in a broad sense, for example, it may be being fixedly connected, may be a detachable connection, or integrally Connection；It can be mechanical connection, can also be electrical connection；Can be directly connected, can also indirectly connected through an intermediary, It can be the connection inside two elements.For the ordinary skill in the art, it can understand above-mentioned art with concrete condition The concrete meaning of language in the present invention.

In addition, as long as technical characteristic involved in the utility model different embodiments disclosed below is each other Not constituting conflict can be combined with each other.

Embodiment 1

The present embodiment is specifically described below in conjunction with the accompanying drawings：

The utility model provides a kind of miniature circuit breaker as shown in Figs 1-4, including shell 1, is installed in the shell 1 Operating mechanism 2, contact mechanism and overload protecting mechanism, the operating mechanism 2 drives 3 He of moving contact in the contact mechanism The contact of static contact 4 is closed a floodgate, alternatively, driving the moving contact 3 with the static contact 4 far from separating brake；

The overload protecting mechanism includes bimetal leaf 51 and heat-conducting piece 52, and, it is touched under bimetal leaf effect Sending out operating mechanism described drives the driving member 55 of the contact mechanism separating brake；One end of the heat-conducting piece 52 and the moving contact 3 Connection, the other end are connect with outlet side terminal 6, are formed through the moving contact when moving contact 3 closes a floodgate with the static contact 4 3 and the heat-conducting piece 52 be transferred to the galvanic circle of the outlet side terminal 6, the bimetal leaf 51 and the heat-conducting piece 52 Thermal conductive contact, the heat-conducting piece are less than the resistivity of bimetal leaf by T1 red copper integrally casting shapings, resistivity.

The above embodiment is the core technology scheme of the present embodiment, and overload protecting mechanism includes the bimetallic of thermal conductive contact Piece 51 and heat-conducting piece 52, one end of heat-conducting piece are connect with the moving contact, and the other end is connect with outlet side terminal, this structure Setting, constitutes galvanic circle, the heat-conducting piece 52 is sent out when passing through electric current by moving contact 3, heat-conducting piece 52 and outlet side terminal 6 Heat will not constitute power circuit to carry out auxiliary heating to bimetal leaf 51 since bimetal leaf does not connect load, to Bimetal leaf is overcome the problems, such as by current limit, therefore, when bimetal leaf 51 is heated reaches overload temperature, can be bent naturally dynamic Make and drives operating mechanism 2 to carry out sub-switching operation by driving member 55, i.e., dynamic and static contact separation.Using the utility model technology Scheme, 52 resistivity of the heat-conducting piece are less than the resistivity of bimetal leaf 51, have excellent electric conductivity, thermal conductivity and processing Performance, promotes the conductive capability of heat-conducting piece, and technical staff can be according to the design specification of miniature circuit breaker to the specification of heat-conducting piece It is accordingly selected, neither changes bimetal leaf, and can avoid the design method using two-way electric current, with the reality of galvanic circle all the way Existing miniature circuit breaker meet more high current by design requirement, stability is more preferable, and debugging is simple and more acurrate, and it is difficult to reduce design Degree, makes miniature circuit breaker be truly realized the high current specification more than 63A, highly practical, widely used.

In the present embodiment, for the heat-conducting piece preferably by T1 red copper integrally casting shapings, T1 red coppers are that oxygen and impurity contain Fine copper extremely low, that purity is high is measured, interior impurity is discharged by oxidation, and solid solution capacity reduces the electrical conductance for being conducive to T1 red coppers, also may be used The influence of objectionable impurities is eliminated, for copper content 99.95% or more, impurity summation is no more than 0.05%.Therefore, T1 red coppers have very Good conductivity and thermal conductivity, it is corresponding to reduce obstruction ability of the electric current by heat-conducting piece, so that bimetal leaf 51 is matched with heat-conducting piece 52 It closes using more stable and reliable.Wherein, T1 red coppers can be used for welding, so as to so that the both ends connection moving contact of heat-conducting piece and outlet The side terminal period of the day from 11 p.m. to 1 a.m realizes welding procedure processing by annealed copper wire.Obviously, the heat-conducting piece 52 is a kind of not just for T1 red coppers, Other materials with excellent conductive capability and heat conductivility, such as oxygen-free copper TUI and TU2 etc. are can also be, herein not to leading The other structures of warmware repeat one by one.

Made further preferably according to the above embodiment, the heat-conducting piece is the piece extended side by side with the bimetal leaf 51 Shape structure, the bimetal leaf 51 fit in 52 side of the heat-conducting piece, realize the auxiliary between bimetal leaf 51 and heat-conducting piece Heating, contact area is big, and heat-conducting effect is more preferable, and the heat being transmitted on bimetal leaf 51 is more stable and concentrates, and makes small-sized open circuit Device realizes trip operation at the appointed time when doing trip-gear, promote product performance.In the present embodiment, the heat-conducting piece It substitutes bimetal leaf and forms galvanic circle in overload protecting mechanism, the cross-sectional area of heat-conducting piece is increased to meet phase by selection Induced current by bearing requirements, and bimetal leaf flexure operation at once when reaching the overload temperature of setting do not influence bimetallic The normal work of piece, so as to promoted miniature circuit breaker allow by operating current, realization accomplish 80A and the above electric current rule The purpose of lattice.

Specifically, the bimetal leaf 51 by adhesive glue sticker in the heat-conducting piece 52 backwards to the moving contact 3 side Face.This structure setting, it is convenient to be connected, and adhesive glue uses the preferable colloid of heat conductivility, not only can efficiently transmit heat, but also Fixed function can be achieved；And it can be backwards to moving contact when bimetal leaf 51 reaches overload temperature according to the characteristic of bimetal leaf 51 3 direction flexure operation, to drive driving member 55 with the sub-switching operation of pneumatic operating mechanism realization contact mechanism.

In conjunction with shown in Fig. 1-2, one end of the bimetal leaf 51 is the fixing end with 52 secure fit of the heat-conducting piece, separately One end is the free end of heated bending；The free end is connected with the driving member, and the behaviour is triggered by the driving member 55 Make mechanism 2 and drives the contact mechanism separating brake.As a kind of specific set-up mode, the fixing end and 52 end of the heat-conducting piece Portion is concordant, and the two is fixedly installed in the clip position on the shell 1, the free end beyond the heat-conducting piece 52 set away from From, be conducive to the free end of bimetal leaf 51 and bend in overload, to by the free end push driving member 55 to Direction movement far from moving contact 3, makes operating mechanism drive the contact mechanism separating brake under the drive of driving member.

The position of bimetal leaf and heat-conducting piece is adjusted and is fixed for convenience, as Figure 2-3, the shell The positioning adjusting part of bimetal leaf 51 and the heat-conducting piece 52 described in fixed clamp, the positioning adjusting part are provided on 1 Including the positioning plate 53 being installed in the shell 1, and the adjusting spiral shell that is removably set in 1 molding pilot hole of the shell Silk 54, the positioning plate 53 and the adjusting screw 54 form the folder that the bimetal leaf 51 and heat-conducting piece 52 is clamped in opposite directions Position is held, by rotating adjusting screw 54 for finely tuning relative position of the bimetal leaf 51 in the shell 1.By upper Structure is stated it is found that the positioning plate 53 and the adjusting screw 54 are clamped the one of the bimetal leaf 51 and heat-conducting piece 52 in opposite directions End, when finely tuning 51 position of bimetal leaf, only needs to play fixed function in shell to bimetal leaf and heat-conducting piece By rotating the stroke distances of the adjusting screw 54 tune is played to be finely adjusted to the fixed position of bimetal leaf 51 Save the purpose of distance between bimetal leaf and driving member so that the driving of bimetal leaf overload bending is apart from shorter, triggering more and When, cooperation is accurate and reliable, easy to adjust.

As a preferred embodiment, as shown in figure 4, the both ends side of the heat-conducting piece 52 has been separately formed the first line of a couplet Fishplate bar 521 and second line of a couplet fishplate bar 522, the upper gusset piece 521 are connected by soft strength with the moving contact 3, the second line of a couplet fishplate bar 522 connect with the outlet side terminal 6, can directly weld or soft strength.This structure setting, upper gusset piece 521 and the second line of a couplet Fishplate bar 522 is respectively the wiring position demand that the both ends of the heat-conducting piece provide connection moving contact and outlet side terminal, just In patching operations, and the installation site of bimetal leaf is not influenced, reasonable design, cooperation is reliably.

It elaborates below in conjunction with the concrete structure of the operating mechanism of Fig. 1-3 pairs of the present embodiment：

The operating mechanism 2 includes：Operation handle, contact supporting, resetting spring, tripping and lock；The contact supporting 21, it is rotatably provided in the shell 1；The moving contact 3 be mounted on the contact supporting 21 on and with the contact supporting Linkage setting；One end of the resetting spring 24 is connected to the shell 1, and the other end is connected to the contact supporting 21, described Resetting spring 24 applies to the contact supporting 21 drives the moving contact 3 to tend to the active force detached with the static contact 4；Institute It states tripping 22 and is rotatably provided in the contact supporting 21, link with the operation handle；The lock 23 is pivotally mounted to The contact supporting 21, when coordinating with the tripping, the contact supporting 21 drives described dynamic under operation handle effect Contact 3 moves；It is detached from and coordinates with the tripping 22, described in the contact supporting 21 drives under the action of the resetting spring 24 Moving contact 3 is far from the static contact 4；Specifically, the bimetal leaf 51 drives the lock 23 de- by the driving member 55 From the cooperation with the tripping 22.

And the closing by hand and dropout separating brake process of miniature circuit breaker are illustrated in conjunction with Fig. 1 and Fig. 2：

When breaker closing by hand, the operation handle drives the tripping 22 to rotate when rotating, realize the tripping 22 With the lock fit of the lock 23, in locking process, the tripping 22 pulls the support 21 together with the lock 23 Rotation, and drive the moving contact 3 to be contacted with static contact 4 by the support 21, the resetting spring energy storage at this time.And work as When bimetal leaf overload in overload protecting mechanism bends, pulls the lock 23 to rotate by driving member and be detached from and jump The lock fit of button 22, the tripping 22 and the active force of described 23 pairs of supports 21 of lock for releasing cooperation disappear, institute Return under the action of resetting spring of support 21 is stated, to drive the moving contact 3 to be detached with static contact 4, breaker at this time Dropout separating brake.

In the present embodiment, the driving member 55 is pull rod, and one end of the pull rod is fixed on the lock 23, another It holds and extends to 51 side of the bimetal leaf and be oppositely arranged with the free end.The advantages of this arrangement are as follows passing through pull rod The flecition power of bimetal leaf is transmitted, i.e., the described 23 generation rotation under the pulling force effect of the pull rod of lock, to release The matching relationship of lock 23 and tripping 22, to achieve the purpose that the thermal tripping of breaker is protected, securely and reliably.

Obviously, the above embodiments are merely examples for clarifying the description, and does not limit the embodiments.It is right For those of ordinary skill in the art, can also make on the basis of the above description it is other it is various forms of variation or It changes.There is no necessity and possibility to exhaust all the enbodiments.And it is extended from this it is obvious variation or Among the protection domain that variation is created still in the utility model.

Claims (10)

1. a kind of miniature circuit breaker, including shell (1), be installed on operating mechanism (2) in the shell (1), contact mechanism and Overload protecting mechanism, the operating mechanism (2) drive moving contact (3) and static contact (4) contact combined floodgate in the contact mechanism, Alternatively, driving the moving contact (3) with the static contact (4) far from separating brake；

It is characterized in that：The overload protecting mechanism includes bimetal leaf (51) and heat-conducting piece (52), and, in the bimetallic The piece effect lower triggering operating mechanism drives the driving member (55) of the contact mechanism separating brake；One end of the heat-conducting piece (52) It is connect with the moving contact (3), the other end is connect with outlet side terminal (6), the moving contact (3) and the static contact (4) The galvanic circle that the outlet side terminal (6) is transferred to through the moving contact (3) and the heat-conducting piece (52) is formed when combined floodgate, The bimetal leaf (51) and the heat-conducting piece (52) thermal conductive contact；Heat-conducting piece (52) resistivity is less than the bimetal leaf (51) resistivity.

2. miniature circuit breaker according to claim 1, it is characterised in that:The heat-conducting piece (52) be and the bimetal leaf (51) laminated structure extended side by side, the bimetal leaf (51) fit in the heat-conducting piece (52) side.

3. miniature circuit breaker according to claim 2, it is characterised in that:The bimetal leaf (51) passes through adhesive glue sticker In the heat-conducting piece (52) backwards to the side of the moving contact (3).

4. miniature circuit breaker according to claim 2 or 3, it is characterised in that:One end of the bimetal leaf (51) be with The fixing end of heat-conducting piece (52) secure fit, the other end are the free end of heated bending；The free end and the transmission Part (55) is connected, and triggering the operating mechanism by the driving member (55) drives the contact mechanism separating brake.

5. miniature circuit breaker according to claim 4, it is characterised in that：The fixing end is flat with the heat-conducting piece end Together, the two is fixedly installed in the clip position on the shell (1), the free end beyond the heat-conducting piece (52) set away from From.

6. miniature circuit breaker according to claim 5, it is characterised in that：It is provided with fixed clamp institute on the shell (1) The positioning adjusting part of bimetal leaf (51) and the heat-conducting piece (52) is stated, the positioning adjusting part includes being installed on the shell Positioning plate (53) in body (1), and the adjusting screw (54) that is removably set in the shell (1) molding pilot hole, institute It states positioning plate (53) and the adjusting screw (54) and is formed in opposite directions and the described of the bimetal leaf (51) and heat-conducting piece (52) is clamped Clip position, by rotating adjusting screw (54) for finely tuning relative position of the bimetal leaf (51) in the shell.

7. miniature circuit breaker according to claim 5 or 6, it is characterised in that:The both ends side of the heat-conducting piece (52) point Gusset piece (521) and second line of a couplet fishplate bar (522) are not formed, and the upper gusset piece (521) passes through soft strength and the moving contact It is connected, the second line of a couplet fishplate bar (522) connect with the outlet side terminal (6).

8. miniature circuit breaker according to claim 1, it is characterised in that:The heat-conducting piece (52) is by T1 red copper integrally castings Molding.

9. miniature circuit breaker according to claim 4, which is characterized in that the operating mechanism (2) includes：

Operation handle；

Contact supporting (21) is rotatably provided in the shell (1)；The moving contact (3) is mounted on the contact supporting (21) it links on and with the contact supporting and is arranged；

Resetting spring (24), one end are connected to the shell (1), and the other end is connected to the contact supporting (21), the reset Spring (24) applies to the contact supporting (21) drives the moving contact (3) to tend to the effect detached with the static contact (4) Power；

Tripping (22) is rotatably provided in the contact supporting (21), links with the operation handle；

It latches (23), is pivotally mounted to the contact supporting (21), when coordinating with the tripping (22), the contact supporting (21) moving contact (3) is driven to move under operation handle effect；It is detached from and coordinates with the tripping (22), the contact Holder (21) drives the moving contact (3) far from the static contact (4) under the action of the resetting spring (24)；

The bimetal leaf drives the lock to be detached from the cooperation with the tripping by the driving member.

10. miniature circuit breaker according to claim 9, it is characterised in that：The driving member (55) is pull rod, the pull rod One end be fixed on the lock (23), the other end to the bimetal leaf (51) side extend and it is opposite with the free end Setting.