CN217061984U - Small-sized circuit breaker - Google Patents

Abstract

A miniature circuit breaker comprises a shell, a pair of wiring terminals, a handle mechanism and at least two action units arranged in parallel, wherein the at least two action units are matched with the same operation mechanism, each action unit comprises an arc extinguishing system and a contact mechanism, the arc extinguishing system comprises an arc extinguishing chamber, the contact mechanism comprises a moving contact and a fixed contact which are matched with each other, the fixed contact is fixedly arranged on one side of the arc extinguishing chamber, the moving contact and the fixed contact are arranged oppositely, the moving contacts of the at least two action units are electrically connected in a flexible connection mode, a thermal tripping mechanism and an electromagnetic tripping mechanism are further arranged in the shell, and the moving end of the thermal tripping mechanism and one end of the electromagnetic tripping mechanism are respectively matched with the operation mechanism. The utility model discloses two adjacent action units's moving contact is connected through flexonics's mode electricity for certain contact pressure and reliable contact still can be guaranteed to two adjacent action units's contact mechanism under the inconsistent circumstances of wearing and tearing.

Description

Small-sized circuit breaker

Technical Field

The utility model relates to a low voltage distribution system, concretely relates to miniature circuit breaker.

Background

In a low-voltage distribution system, a circuit breaker is widely used as a switching device for protecting power supply safety. In recent years, with the development of a photovoltaic system from DC1000V to DC1500V, the performance requirement of a DC circuit breaker for photovoltaic is also higher, and the single-break contact structure of the conventional miniature circuit breaker cannot meet the design requirements of high-voltage breaking arc-quenching, electrical clearance and creepage distance of the DC1500V system, so that the double-break contact structure constitutes a better solution.

However, most of the existing miniature circuit breakers with a double-break contact structure adopt a pair of parallel moving contacts in rigid connection, which can greatly increase the arc voltage during breaking and shorten the arc extinguishing time, but as the breaking times increase, the two pairs of moving and static contacts are inevitably worn, so that the contact parameters (open distance, over travel and contact pressure) of the two pairs of moving and static contacts are inconsistent, and the temperature rise of the circuit breaker is very high, which causes fire hazard.

Disclosure of Invention

An object of the utility model is to overcome prior art's defect, provide a simple structure, miniature circuit breaker that the reliability is high.

In order to achieve the above purpose, the utility model adopts the following technical scheme:

a miniature circuit breaker comprises a shell, a pair of wiring terminals are arranged at two ends of the shell, a handle mechanism is rotatably arranged on the shell, at least two action units are arranged between the pair of wiring terminals in parallel, the at least two action units are matched with the same operating mechanism, each action unit comprises an arc extinguishing system and a contact mechanism, the handle mechanism is linked with the operating mechanism, the arc extinguishing system comprises an arc extinguishing chamber, the contact mechanism comprises a moving contact and a static contact which are matched with each other, the static contact is fixedly arranged at one side of the arc extinguish chamber, the moving contacts are arranged opposite to the static contact, the moving contacts of at least two action units are electrically connected in a flexible connection mode, the shell is also internally provided with a thermal tripping mechanism and an electromagnetic tripping mechanism, and the movable end of the thermal tripping mechanism and one end of the electromagnetic tripping mechanism are respectively matched with the operating mechanism.

Further, operating device includes the lever, and every action unit all includes that one rotates the contact support of assembly on the lever, and every moving contact supports with a contact and is connected, and every contact support is provided with a torsional spring respectively, and the both ends of every torsional spring support with the contact respectively, the lever supports to lean on the cooperation, and two adjacent moving contacts are connected through the flexible coupling electricity.

Furthermore, at least one middle cover is arranged in the shell, arc extinguishing systems of two adjacent action units are respectively assembled on the front side and the back side of the middle cover, contact mechanisms of the two adjacent action units are separated by the middle cover, and one end of the middle cover is provided with a blocking part for separating the moving contact from the thermal tripping mechanism.

Further, at least one end joint of shell has insulating barrier, insulating barrier includes the connecting plate and sets up the division board on the connecting plate, connecting plate and shell joint, division board are corresponding to between two binding post of two adjacent circuit breakers with the one end.

Furthermore, the isolating plate is provided with a knocking-off structure, and when at least two circuit breakers are connected in series, the two adjacent insulating isolating plates are communicated through the knocking-off structure.

Furthermore, connecting row connectors corresponding to the wiring terminals are respectively arranged at two ends of the shell, the connecting row connectors are located above the wiring ports, the knocking-off structures correspond to the connecting row connectors, the knocking-off structures are breaking grooves formed in the end portions, close to one ends, of the isolation plates, the length of the isolation plates is larger than that of the connecting plates, the connecting plates do not shield the connecting row connectors, and the knocking-off structures arranged on the isolation plates in a breaking mode can enable the connecting row connectors of two adjacent miniature circuit breakers to be communicated.

Further, operating device includes lever, contact support, hasp, jump and detain, the dropout couple, torsional spring and mechanism main spring, the lever rotates to be assembled in the shell, and contact support rotates to be assembled on the lever, and moving contact rotates to be assembled on contact support, and hasp and jump detain respectively rotate to be assembled on the lever, hasp cooperation with the one end hasp of jumping the knot, and the other end of hasp is relative with electromagnetic tripping device, and the dropout couple is connected at the other end of hasp and is relative with thermal tripping device, the torsional spring rotates to be assembled on contact support, and the both ends of torsional spring support with the contact respectively, the lever supports to lean on the cooperation, and the both ends of mechanism main spring are connected with lever, shell respectively.

Further, the arc extinguishing system still includes run-on angle, flash barrier and permanent magnet, the one end of stopping part is kept away from to the explosion chamber fixed well lid, and the run-on angle sets up along the one end that well lid was equipped with the stopping part, and the flash barrier sets up between explosion chamber and stopping part, and the permanent magnet setting is in one side of run-on angle back to the explosion chamber.

Furthermore, the positive and negative both sides protrusion of well lid is equipped with fixed muscle and convex structure, fixed muscle is used for the fixed arc extinguishing bars piece of explosion chamber of cooperation, and convex structure is fixed with the groove structure cooperation of flash barrier wall.

Further, the thermal trip mechanism comprises a bimetallic strip, one end of the bimetallic strip is fixed on the shell, and the other end of the bimetallic strip is opposite to the operating mechanism.

The utility model discloses a miniature circuit breaker, two adjacent action units's moving contact are connected through flexonics's mode electricity for certain contact pressure and reliable contact still can be guaranteed to two adjacent action units's contact mechanism under the inconsistent condition of wearing and tearing.

In addition, the middle cover arranged in the shell provides an assembly position for an arc extinguishing system of the action unit, and the moving contact and the thermal tripping mechanism are separated by the blocking part arranged at one end of the middle cover, so that the thermal tripping mechanism is prevented from being interfered by electric arc generated by the disjunction of the contact mechanism.

In addition, at least one end joint insulating barrier of shell, when concatenating the circuit breaker of two poles or more than two poles of the earth, can be in order to increase the creepage distance between the binding post of adjacent two poles of the earth circuit breaker, in addition, reduce the size of baffle after the rupture groove is broken and make two adjacent insulating barriers keep communicateing, do benefit to the wire length when shortening two adjacent action units that concatenate, reduce product cost.

Drawings

FIG. 1 is a schematic view of the present invention;

fig. 2 is a schematic structural diagram of the operating mechanism, the electromagnetic trip mechanism and the thermal trip mechanism of the present invention;

fig. 3 is a schematic structural view (front side) of the middle arc extinguishing system and the middle cover of the present invention;

fig. 4 is a schematic structural view (reverse side) of the middle arc extinguishing system and the middle cover of the present invention;

FIG. 5 is a schematic structural view (front view) of the middle cover of the present invention;

FIG. 6 is a schematic structural view (reverse side) of the middle cover of the present invention;

FIG. 7 is a schematic structural view of the housing and the insulating partition plate according to the present invention;

FIG. 8 is a schematic structural view of an insulating spacer according to the present invention;

fig. 9 is a schematic view of the insulating barrier connection of a plurality of circuit breakers of the present invention;

fig. 10 is a schematic structural view of an operating mechanism of the present invention;

fig. 11 is a schematic structural diagram of the operating mechanism of the present invention (without a jump button);

fig. 12 is a schematic circuit diagram of the contact mechanism of the present invention.

Detailed Description

The following describes a detailed embodiment of a miniature circuit breaker according to the present invention with reference to the embodiments shown in fig. 1 to 12. The present invention is not limited to the description of the following embodiments.

As shown in fig. 1, a miniature circuit breaker includes a housing 1, which generally includes a base 11 and an upper cover 12 that are covered with each other, a pair of terminals 2 and a pair of connection ports 105 are respectively provided at both ends of the housing 1, and the terminals 2 respectively correspond to the connection ports 105. The miniature circuit breaker of the application is a single-pole circuit breaker suitable for high voltage environment, at least two action units are arranged between a pair of wiring terminals 2 in parallel along the width direction of the circuit breaker, at least two action units share one operating mechanism 4, each action unit comprises a contact mechanism and an arc extinguishing system 6, the contact mechanism comprises a moving contact 51 and a static contact 52 which are matched with each other, wherein the static contact 52 is fixedly assembled at the middle part of a shell 1, the moving contact 51 is connected on the operating mechanism 4 and is opposite to the static contact 52, the moving contacts 51 of the two action units are electrically connected, the static contact 52 of one action unit is electrically connected with one wiring terminal 2, the static contact 52 of the other action unit is electrically connected with the other wiring terminal 2, the breakpoints of the moving contact and the static contact of the two action units are used for improving the arc voltage when the short circuit is broken, the operating mechanism 4 is connected with a handle mechanism 3 which is rotatably assembled on the shell 1 in a linkage way, the swing handle mechanism 3 drives the operating mechanism 4 to drive the contact mechanisms of the action units to perform opening and closing actions, and the arc extinguishing system 6 is arranged on one side of the contact mechanisms in a matched mode and used for extinguishing electric arcs generated when the contact mechanisms are broken.

A protection mechanism can be further arranged in the housing 1, the protection mechanism is matched with the operating mechanism 4 to realize short circuit and/or overload protection, the protection mechanism comprises an electromagnetic tripping mechanism 7 and/or a thermal tripping mechanism 8, and only one electromagnetic tripping mechanism 7 and/or one thermal tripping mechanism 8 can be respectively arranged.

One improvement point of the present application is that the moving contacts 51 of two adjacent action units are electrically connected in a flexible connection manner, so that the contact mechanisms of two adjacent action units can still ensure a certain contact pressure and reliable contact under the condition of inconsistent wear.

Specifically, as shown in fig. 2, 10 and 11, the actuating unit disposed in the housing 1 includes at least one lever 41 rotatably assembled, the contact mechanisms of two adjacent actuating units are connected to the same lever 41, each contact mechanism includes a contact support 43 and a torsion spring 46, the contact support 43 is rotatably connected to the lever 41, the torsion spring 46 is rotatably assembled on the contact support 43, two ends of the torsion spring 46 respectively abut against the lever 41 and the contact support 43 to provide contact pressure for the movable contacts 51, that is, the two torsion springs 46 respectively provide torque for the two movable contacts 51, so as to generate final pressure to the stationary contacts 52, the movable contacts 51 of each actuating unit are respectively connected to one contact support 43, the two adjacent movable contacts 51 are electrically connected through a soft coupling 511, compared with an integrated structure in which the two movable contacts 51 are rigidly connected in the prior art, the rotation angles of the two movable contacts 51 during simultaneous actuation are necessarily the same, when the wear degrees of the moving contacts 51 or the fixed contacts 52 are inconsistent, the two adjacent moving contacts 511 are flexibly connected through the torsion spring 46 and the flexible coupling 511, even if the two moving contacts 511 are worn inconsistently, a certain contact pressure and reliable contact can be still ensured, that is, after the pair of moving contacts 51 and the fixed contacts 52 in one action unit are contacted, the pair of moving contacts 51 and the fixed contacts 52 in the other action unit can be contacted again through the torsion spring 46 of the other action unit and provide final pressure.

Further, the operating mechanism 4 further includes a jump buckle 44 and a lock catch 45 rotatably mounted on the lever 41, the jump buckle 44 is in snap fit with one end of the lock catch 45, and the other end of the lock catch 45 is in fit with the electromagnetic trip mechanism 7 and/or the thermal trip mechanism 8 to achieve protection. Preferably, the lock catch 45 is in linkage connection with the lever 41 through a linkage shaft, so that the action consistency of the adjacent two-pole circuit breaker operating mechanism during tripping is guaranteed, the reset piece 48 is connected to the lock catch 45, and the reset piece 48 is matched with the shell 1 to provide reset force for the lock catch 45.

Another improvement point of the present application is that at least one middle cover 13 is disposed in the housing 1, the middle cover 13 is used for separating the arc extinguishing system 6 and the contact mechanism of each action unit, and the middle cover 13 provides an assembly position for the fixed contact 52 in the arc extinguishing system 6 and the contact mechanism, a blocking portion 132 is further disposed at one end of the middle cover 13, when the thermal trip mechanism 8 is disposed in the housing 1, the moving contact 51 and the thermal trip mechanism 8 are separated by the blocking portion 132, so as to prevent the thermal trip mechanism 8 from being ablated by the arc generated when the contact mechanism is disconnected.

Specifically, as shown in fig. 3 to 6, mounting grooves 131 are formed on the front and back sides of the middle cover 13, preferably, the same positions on the front and back sides of the middle cover 13 are recessed to form opposite mounting grooves 131, arc-extinguishing chamber fixing portions and position-limiting portions 1312 are respectively disposed in the mounting grooves 131, the fixed contact 52 of the contact mechanism is fixedly mounted in the middle of the mounting groove 131, wherein the arc-extinguishing chamber fixing portions are preferably a plurality of fixing ribs 1311 with bar-shaped protrusions that are parallel and spaced, a plurality of arc-extinguishing grid plates are stacked in the arc-extinguishing chamber 61 of the arc-extinguishing system 6, the arc-extinguishing grid plates are fixed on the middle cover 13 by being matched with the fixing ribs 1311, the position-limiting portions 1312 and the fixing ribs 1311 are respectively disposed on the two sides of the fixed contact 52, preferably, the position-limiting portions 1312 and the fixed contact 52 are inclined to be opposite to limit the arc-striking angle 62 in the arc-extinguishing system 6, and a blocking portion 132 opposite to the fixed contact 52 is formed by extending outward from the edge of the mounting groove 131 far from one end of the fixing rib 1311, the movable contact 51 swings between the stopper 132 and the fixed contact 52, and when the thermal trip mechanism 8 is provided on the operating mechanism 4 side of each operating unit, the stopper 132 located between the movable contact 51 and the thermal trip mechanism 8 prevents the thermal trip mechanism 8 from being ablated by an arc generated by the contact mechanism breaking.

The application has a further improvement point that at least one end of the shell 1 is detachably provided with an insulating partition 14 (see fig. 7-9), the insulating partition 14 is fixed with the shell 1 through a clamping structure in a clamping mode, the insulating partition 14 comprises a connecting plate 141 and two partition plates 142, a threading opening 1412 corresponding to the wiring opening 105 is formed in the connecting plate 141 so as to facilitate external threading, the two partition plates 142 are arranged on two sides of the threading opening 1412 at intervals and used for isolating the wiring terminals 2 at the same end of two adjacent circuit breakers, a knocking-off structure is arranged on at least one partition plate 142, and the two adjacent insulating partitions 14 are communicated through breaking the knocking-off structure arranged on the partition plates 142. Two division boards 142 of this embodiment are connected perpendicularly on connecting plate 141, and when two poles or the miniature circuit breaker more than two poles of the earth concatenate, the same binding post 2 of end is kept apart to two adjacent pole circuit breakers by division board 142 to this creepage interval between two adjacent binding post 2 of increase. When two poles of the earth circuit breakers need to be connected in series, the two insulation partition plates 142 are communicated through the knock-off structure arranged on the partition plates 142 in a breaking manner, so that the length of a wire when two adjacent circuit breakers are connected in series is shortened, the product cost is reduced, and the safety is improved. Of course, the insulating partition 14 is applicable not only to the embodiment having a plurality of action units, but also to the embodiment having only a single action unit, i.e., one movable contact and one fixed contact.

Preferably, two ends of the housing 1 are respectively provided with a connecting bar connecting port corresponding to the connecting terminal 2 for installing the connecting bar to be electrically connected with the connecting terminal, the connecting bar connecting port is located above the connecting port 105, the knock-out structure corresponds to the connecting bar connecting port, and the knock-out structure arranged on the isolation plate 142 is broken to connect the connecting bar connecting ports of the miniature circuit breakers of two adjacent poles. Preferably, the length of the isolation plate 142 is greater than that of the connection plate 141, the connection plate 141 does not shield the connection row connection port, and the knock-out structure on the isolation plate 142 corresponds to the connection row connection port to isolate the connection row connection port of the adjacent circuit breaker. Of course, the connection plate 141 may be provided with a coupling line hole corresponding to the coupling line connection port.

Preferably, the knock-off structure is a breaking groove 1422 formed in the end portion, close to one end, of the isolation board 142, the breaking groove 1422 is broken to shorten the length of the isolation board 142, so that the upper portions of the two adjacent insulation isolation boards 14 are communicated, and connection between the two circuit breakers through a connecting row is facilitated, so that an overlong wire is replaced, the cost is reduced, in addition, the breaking groove 1422 is convenient to process, the length of the isolation board 142 can be shortened quickly and conveniently, and the two adjacent insulation isolation boards 14 are communicated quickly.

Further, the clamping structure disposed between the insulating partition 14 and the housing 1 includes a first clamping portion 1411, a first clamping groove 102, a second clamping portion 1421, and a second clamping groove 103, wherein the first clamping portion 1411 and the first clamping groove 102 are disposed on the connecting plate 141 and the housing 1 in a matching manner, the second clamping portion 1421 and the second clamping groove 103 are disposed on the isolating plate 142 and the housing 1 in a matching manner, preferably, a terminal of the second clamping groove 103 bends to one side to form a clamping area 104, a terminal of the second clamping portion 1421 bends to one side to form a clamping portion 1423 matched with the clamping area 104, and the second clamping portion 1421 and the second clamping groove 103 adopt an asymmetric structure to provide a guiding effect, thereby enhancing the clamping stability.

With reference to fig. 1 to 9, a specific embodiment of a miniature circuit breaker is provided, where the miniature circuit breaker includes a housing 1 formed by covering an upper cover 12 and a base 11, a handle mechanism 3 is rotatably assembled on an upper portion of the housing 1, a pair of connection terminals 2 are disposed at two ends of the housing 1 and correspond to connection ports 105 disposed at two ends of the housing 1, one of the connection terminals 2 is an incoming terminal, in this embodiment, the connection terminal 2 at the right end of the housing 1 is an incoming terminal, and the other connection terminal 2 is an outgoing terminal, in this embodiment, the connection terminal 2 at the left end of the housing 1 is an outgoing terminal; two action units are arranged in parallel in the middle of the shell 1 between the incoming line terminal and the outgoing line terminal, the two action units share one operating mechanism 4, each action unit comprises an arc extinguishing system 6 and a contact mechanism, the operating mechanism 4 is in linkage connection with the handle mechanism 3 through a connecting rod, the contact mechanisms respectively comprise a moving contact 51 and a fixed contact 52 which are matched with each other, the moving contact 51 is correspondingly connected onto the operating mechanism 4, the fixed contact 52 and the arc extinguishing system 6 are fixedly assembled on one side opposite to the moving contact 51 of each action unit and are positioned below the handle mechanism 3, the moving contacts 51 of the two action units are in flexible connection, and when the abrasion degrees of the contact mechanisms of the two action units are inconsistent, certain contact pressure and reliable contact can be still ensured.

As shown in fig. 1-2, in the present embodiment, a thermal trip mechanism 8 and an electromagnetic trip mechanism 7 are disposed in a housing 1, the thermal trip mechanism 8 and the electromagnetic trip mechanism 7 are respectively disposed at two sides of an operating mechanism 4, wherein the thermal trip mechanism 8 is disposed in the housing 1 between a movable contact 51 and a wire inlet terminal, a stationary contact 52 of one of the operating units is electrically connected to the wire inlet terminal through the thermal trip mechanism 8, the electromagnetic trip mechanism 7 is disposed between the stationary contact 52 and a wire outlet terminal, the electromagnetic trip mechanism 7 is disposed between an arc extinguishing system 6 and a handle mechanism 3 of all the operating units, a stationary contact 52 of the other operating unit is electrically connected to the wire outlet terminal through the electromagnetic trip mechanism 7, two adjacent movable contacts 51 are electrically connected through a soft link 511, and a current of a circuit breaker sequentially passes through the wire inlet terminal, the thermal trip mechanism 8, and a contact mechanism of one of the operating units, The contact mechanism of the other action unit, the electromagnetic tripping mechanism 7 and the outlet terminal.

As shown in fig. 2, 10 and 11, the operating mechanism 4 includes a lever 41, a latch 45, a jumper 44, a trip hook 47, and a mechanism main spring 42, and the contact mechanisms each include a contact support 43 and a torsion spring 46; wherein the lever 41 is rotatably assembled in the housing 1, the two contact supports 43 are respectively rotatably assembled on the front side and the back side of the lever 41, the jump buckle 44 and the lock catch 45 are rotatably assembled on the lever 41, specifically, two convex shafts which are respectively used for rotatably assembling the jump buckle 44 and the lock catch 45 are arranged on one side of the lever 41, the jump buckle 44 is in snap fit with one end of the lock catch 45, one end of the jump buckle 44 is connected with a connecting rod connected with the handle mechanism 3, the trip hook 47 is connected with the other end of the lock catch 45, the trip hook 47 is matched with the movable end of the thermal trip mechanism 8, when a short circuit fault occurs, the push rod opposite to the lock catch 45 by the electromagnetic trip mechanism 7 triggers the lock catch 45 to rotate so that the snap structures of the jump buckle 44 and the lock catch 45 are collapsed, or, when an overload fault occurs, the thermal trip mechanism 8 triggers the trip hook 47, the lock catch 45 rotates so that the snap structures of the jump buckle 44 and the lock catch 45 are collapsed, the lock catch 45 is in linkage connection with the lever 41 through a linkage shaft, so that the action consistency of the circuit breaker operating mechanisms of the two adjacent poles is guaranteed when tripping is conducted, one end, matched with the electromagnetic tripping mechanism 7 and the thermal tripping mechanism 8, of the lock catch 45 is located between the two contact supports 43, the lock catch 45 is further connected with a resetting piece 48, the resetting piece 48 and the tripping buckle 44 are respectively located on the front side and the back side of the lock catch 45, one end of the resetting piece 48 is connected with the lock catch 45, the other end of the resetting piece 48 is provided with a wavy elastic arm, and the wavy elastic arm is matched with and extruded with the inner side wall of the shell 1 to provide elastic resetting force for the lock catch 45; the torsion spring 46 is rotatably assembled on the contact support 43, that is, the center of the torsion spring 46 is fixed at the rotation center of the contact support 43, one end of the torsion spring 46 abuts against and is matched with a boss arranged on the contact support 43, the other end of the torsion spring 46 abuts against and is matched with a boss arranged on the lever 41, so that two ends of the torsion spring 46 respectively abut against and are matched with the contact support 43 and the lever 41 to provide contact pressure for the movable contact 51, and the mechanism main spring 42 is connected between the lever 41 and the housing 1 and is used for providing closing resistance or resetting force for the contact mechanism during opening.

As shown in fig. 1-4 and 12, the contact mechanism includes a moving contact 51 and a fixed contact 52 that are matched with each other, in this embodiment, the contact mechanism forms two breakpoints in series, that is, the contact mechanism includes two pairs of moving contacts 51 and fixed contacts 52 that are connected in series, wherein one end of each of the two moving contacts 51 that are arranged in parallel is connected to a contact support 43 in each action unit, the two moving contacts 51 are electrically connected through a soft link 511, the two fixed contacts 52 that are arranged in parallel are respectively matched with the two moving contacts 51 that are arranged in parallel, one of the fixed contacts 52 is connected to one of the connection terminals 2 through the thermal trip mechanism 8, and the other fixed contact 52 is connected to the other connection terminal 2 through the electromagnetic trip mechanism 7, preferably, the fixed contact 52 that is close to one side of the base 11 is connected to the thermal trip mechanism 8, and the connection terminal 2 connected to the thermal trip mechanism 8 serves as a wire inlet terminal, the static contact 52 near one side of the upper cover 12 is connected with the electromagnetic tripping mechanism 7, the wiring terminal 2 connected with the electromagnetic tripping mechanism 7 is an outlet terminal, the static contact 52 includes a static contact plate, the static contact plate is disposed along a gap between the arc extinguishing system 6 and the electromagnetic tripping mechanism 7, that is, the static contact plate is disposed along an upper side of the arc extinguishing chamber 61 parallel to the arc extinguishing system 6 in fig. 1, 3 and 4, the other end of the static contact plate is bent back along a static contact mounting portion 1313 in the housing 1 to form an arc guiding portion 521, a static contact matched with the moving contact 51 is arranged on one side of the static contact plate facing the moving contact 51, a connecting part 522 is formed by extending outwards from one side edge of the middle part of the static contact plate, in fig. 4, the connecting portion 522 extends from the middle edge of the arc striking portion 521 to the side of the movable contact 51, which is away from the middle cover 13, i.e., the side close to the side wall of the housing 1, and the connecting portion 522 is electrically connected to the thermal trip unit 8.

As shown in fig. 1, 3 and 4, the arc extinguishing system 6 of each action unit includes an arc extinguishing chamber 61, an arc striking angle 62, an arc barrier wall 63 and a permanent magnet 64, wherein the arc extinguishing chamber 61 is fixed in the installation groove 131, a plurality of arc extinguishing grid pieces are arranged in the arc extinguishing chamber 61 in a stacked manner, the fixed contact 52 is located on one side of the arc extinguishing chamber 61, the movable contact 51 is opposite to the fixed contact 52, the arc striking angle 62 is obliquely opposite to the fixed contact 52, one end of the arc striking angle 62 is located below the movable contact 51, and the other end of the arc striking angle 62 extends into the arc extinguishing chamber 61; the permanent magnets 64 are arranged on one side, back to the arc extinguishing chamber 61, of the arc striking angle 62, and the polarities of the permanent magnets 64 of the two arc extinguishing systems 6 are consistent along the width of the shell 1, so that the generated magnetic field can always ensure that the electric arc between the contact mechanisms in one action unit enters the arc extinguishing chamber 61 to be extinguished; the arc isolating wall 63 made of gas generating material is arranged between the arc extinguishing chamber 61 and the arc striking angle 62, the middle part of the arc isolating wall 63 is provided with a groove structure, the arc striking angle 62 is opposite to the arc striking part 521 of the static contact 52 and forms an arc striking channel on the arc isolating wall 63, after the contact mechanism acts to generate an arc, the arc isolating wall 63 generates gas, so that the local pressure is increased, the arc blowing effect is realized, the arc is elongated, the arc voltage is increased, and the arc extinguishing is facilitated. The permanent magnet 64 may or may not be positioned depending on the performance requirements of the circuit breaker.

The thermal tripping mechanism 8 comprises a bimetallic strip, one end of the bimetallic strip is fixedly connected in the shell 1, the other end of the bimetallic strip is used as a movable end to be matched with the operating mechanism 4, and when an overload fault occurs, the bimetallic strip is heated and bent to trigger the operating mechanism 4 to act. The electromagnetic tripping mechanism 7 comprises a coil and a push rod driven by the coil, the push rod is opposite to the lock catch 45 on the operating mechanism 4, and when a short-circuit fault occurs, the push rod acts to trigger the operating mechanism 4 to act.

As shown in fig. 1 and 3-6, an intermediate cover 13 is further disposed in the housing 1, the intermediate cover 13 is used for separating the arc extinguishing system and the contact mechanism of two adjacent operating units, the arc extinguishing system 6 and the fixed contact 52 of the two operating units are respectively fixed on the front side and the back side of the base 1 and/or the intermediate cover 13, one end of the intermediate cover 13 is provided with a blocking portion 132, the movable contact 51 swings between the blocking portion 132 and the fixed contact 52, the blocking portion 132 separates the movable contact 51 of the two operating units from the thermal trip mechanism 8, so that an arc generated by the contact mechanism breaking is blocked by the blocking portion 132.

As shown in fig. 3-6, the middle cover 13 is integrally formed in a rectangular plate-shaped structure, the front and back sides of the middle cover 13 are respectively recessed to form mounting grooves 131, the two mounting grooves 131 are opposite to each other to form a symmetrical structure, the mounting grooves 131 on the front and back sides of the middle cover 13 are respectively matched with the base 11 and the upper cover 12 to form two chambers, a boss serving as a static contact mounting portion 1313 is protruded from the middle upper portion of the bottom of the mounting groove 131, the static contact mounting portion 1313 is respectively matched with the static contact mounting portion 1313 disposed on the inner side walls of the base 11 and the upper cover 12, one side of the static contact mounting portion 1313 in fig. 3 is a straight side wall, the lower portion of the static contact mounting portion 1313 is in a circular arc shape, one side of the opposite straight side wall is an inclined side wall with an inclined upper end, the other end of the static contact plate is sequentially bent back along the straight side wall, the circular arc-shaped side wall, and the inclined side wall to form an arc-guiding portion 521, a groove or protrusion structure is disposed in the middle of the static contact mounting portion 1313 (see fig. 4), thereby the middle cover 13, the base 11 and the upper cover 12 are mutually matched and connected; a plurality of fixing ribs 1311 with strip-shaped protrusions are arranged in parallel at intervals at the bottom of one side of a fixed contact mounting portion 1313 of the middle cover 13, arc extinguishing grid pieces in the arc extinguishing chamber 61 can be fixed on the middle cover 13 by matching with the fixing ribs 1311, an arc-shaped plate-shaped structure is convexly arranged at the bottom of the other side of the fixed contact mounting portion 1313 of the middle cover 13, one end of the arc-shaped plate-shaped structure extends out of the mounting groove 131 to form a blocking portion 132 opposite to the fixed contact mounting portion 1313, the other end of the arc-shaped plate-shaped structure is obliquely opposite to the fixed contact mounting portion 1313 to form a limiting portion 1312 and is connected with the side wall at the lower portion of the mounting groove 131, the arc-striking angle 62 is fixed on the limiting portion 1312 in a matching manner, one end of the arc-striking angle 62 extends into the arc extinguishing chamber 61 along the side wall at the lower portion of the mounting groove 131 of the middle cover 13, and swings between the fixed contact 52 and the blocking portion 132 along one side of the arc-isolating wall 63 under the driving of the operating mechanism 4; an assembly groove 1314 is arranged at the corner of the installation groove 131 of the limiting part 1312, which is back to the static contact installation part 1313, a permanent magnet 64 is assembled in the assembly groove 1314, a boss structure 1315 is convexly arranged at the bottom of the groove between the blocking part 132 and the fixed rib 1311, the boss structure 1315 is positioned below the static contact installation part 1313, and a groove structure which is matched with the boss structure 1315 in an installation manner is arranged on the arc isolating wall 63; as shown in fig. 3-6, a space is left between the fixing rib 1311 and the side wall of the installation groove 131 at the side far from the blocking portion 132 to serve as an arc runner 1316, two ends of the arc runner 1316 are respectively communicated with the exhaust holes of the housing 1 through a through hole 1318 arranged on the middle cover 13, preferably, a separating portion 1317 is further arranged at one side of the arc runner 1316, the separating portion 1317 is arranged at the side wall of the installation groove 131 far from the blocking portion 132, after the arc extinguishing chamber 61 is assembled, the separating portion 1317 is abutted against and matched with the exhaust end of the arc extinguishing chamber 61 to separate the arc runner 1316 into two parts, in the figure, the arc runner 1316 is divided into an upper part and a lower part by the separating portion 1317, wherein one end of the upper part of the arc runner 1316 is provided with a through hole 1318, and one end of the lower part of the arc runner 1316 extends in the direction far from the blocking portion 132 and is provided with a through hole 1318 communicated with the outside at the end. In addition, in this embodiment, a blocking structure 133 is disposed on the upper portion of the middle cover 13, the blocking structure 133 is located on a side away from the blocking portion 132, the electromagnetic trip mechanism 7 can be assembled on the upper portion of the middle cover 13 between the blocking structure 133 and the blocking portion 132, and the blocking structure 133 can provide a limiting effect for the electromagnetic trip mechanism 7.

As shown in fig. 7 to 9, an insulating spacer 14 is detachably clamped at both ends of the housing 1, in this embodiment, recessed regions are formed on the surfaces of the base 11 and the upper cover 12 at both sides of the wire connection opening 105, the recessed regions are used as insertion grooves 101, the housing 1 can be kept flat after the insulating spacer 14 is matched with the insertion grooves 101, a second clamping groove 103 is further recessed at the bottom of the insertion groove 101, the end of the second clamping groove 103 is bent towards one side to form a clamping region 104, in the figure, two upper and lower second clamping grooves 103 are arranged in the same insertion groove 101 of the upper cover 12 or the base 11, and the end of the second clamping groove 103 is bent towards the lower side in the figure to form a clamping region 104, so that the second clamping groove 103 and the clamping region 104 are integrally formed into an L-shaped groove structure; a first catching groove 102 is provided at one side of the wire connection port 105, and the first catching groove 102 is provided at an upper side of the wire connection port 105 in the drawing.

The insulating partition 14 comprises a connecting plate 141 and two isolating plates 142, the connecting plate 141 is parallel and opposite to the side wall of the shell 1 on one side provided with the wire connecting port 105, a square hole serving as a wire threading port 1412 is formed in the middle of the connecting plate 141, the wire threading port 1412 corresponds to the wire connecting port 105, a U-shaped through hole is formed in the connecting plate 141 on one side of the wire threading port 1412, a clamping plate 1414 is formed in an area surrounded by the U-shaped through hole, a first clamping portion 1411 is formed at the tail end of one side of the clamping plate 1414 in a protruding mode, and the first clamping portion 1411 can be clamped and matched with the first clamping groove 102; the two isolation plates 142 are respectively connected to two sides of the connecting plate 141 and are perpendicular to the connecting plate 141, at this time, the whole insulating partition 14 is in an H shape, one sides of the two isolation plates 142 are inserted into the insertion grooves 101 at two ends of the shell 1, and the thickness of the isolation plates 142 is equal to the recessed degree of the insertion grooves 101, so that the shell 1 is kept flat; a second clamping portion 1421 is disposed on one side of the two isolation plates 142 opposite to each other, the end of the second clamping portion 1421 is bent to one side to form a clamping portion 1423, when the insulating partition 14 is clamped, the clamping portion 1423 first abuts against and cooperates with the second clamping groove 103 and falls into the clamping area 104 along with the connection plate 141 gradually approaching the housing 1, the second clamping portion 1421 cooperates with the second clamping groove 103, and the first clamping portion 1411 is clamped with the first clamping groove 102; the isolating plate 142 is provided with a breaking groove 1422 on one side facing the connecting plate 141, the breaking groove 1422 is flush with one end of the connecting plate 141, when the incoming line terminal or the outgoing line terminal of two circuit breakers needs to be connected in series, the breaking groove 1422 is broken to shorten the length of the isolating plate 142, so that two adjacent insulating partition plates 14 are kept communicated, and a connecting row replaces a lead to connect two adjacent circuit breakers together, which is beneficial to shortening the length of the lead and reducing the cost. As shown in fig. 9, the miniature circuit breakers of the four poles embodiment are riveted together, the connection terminals 2 of the adjacent poles of the circuit breakers are separated by the isolation board 142 to increase the creepage distance of the connection terminals 2 in the two poles of the circuit breakers, the left two poles of the circuit breakers are divided into one group in fig. 9, the right two poles of the circuit breakers are divided into one group, the breaking groove 1422 of the isolation board 142 between the two circuit breakers on the left side is broken, and the breaking groove 1422 of the isolation board 142 between the two circuit breakers on the right side is broken. The four pole circuit breakers can be connected in the factory via a connection board 141 as a complete machine for use in a direct current system, for example, a DC1500V system.

The foregoing is a more detailed description of the present invention, taken in conjunction with specific preferred embodiments thereof, and it is not intended that the invention be limited to the specific embodiments thereof. To the utility model discloses to the ordinary skilled person in technical field's the prerequisite that does not deviate from the utility model discloses under the design, can also make a plurality of simple deductions or replacement, all should regard as belonging to the utility model discloses a protection scope.

Claims (10)

1. The utility model provides a miniature circuit breaker, includes shell (1) the both ends of shell (1) are provided with a pair of binding post (2), rotate on shell (1) and are provided with handle mechanism (3), are provided with two at least action units, its characterized in that between a pair of binding post (2) side by side: the operating mechanism comprises a handle mechanism (3) and an operating mechanism (4), wherein the handle mechanism (3) is in linkage connection with the operating mechanism (4), the arc extinguishing system (6) comprises an arc extinguish chamber (61), a contact mechanism comprises a moving contact (51) and a fixed contact (52) which are matched with each other, the fixed contact (52) is fixedly arranged on one side of the arc extinguish chamber (61), the moving contact (51) and the fixed contact (52) are oppositely arranged, the moving contacts (51) of the at least two operating units are electrically connected in a flexible connection mode, a thermal tripping mechanism (8) and an electromagnetic tripping mechanism (7) are further arranged in the shell (1), and the movable end of the thermal tripping mechanism (8) and one end of the electromagnetic tripping mechanism (7) are respectively matched with the operating mechanism (4).

2. A miniature circuit breaker according to claim 1, wherein: the operating mechanism (4) comprises a lever (41), each action unit comprises a contact support (43) which is rotatably assembled on the lever (41), each moving contact (51) is connected with one contact support (43), each contact support (43) is provided with a torsion spring (46), two ends of each torsion spring (46) are respectively abutted and matched with the contact supports (43) and the lever (41), and two adjacent moving contacts (51) are electrically connected through a flexible coupling (511).

3. A miniature circuit breaker according to claim 1, wherein: at least one middle cover (13) is arranged in the shell (1), the arc extinguishing systems (6) of two adjacent action units are respectively assembled on the front side and the back side of the middle cover (13), the contact mechanisms of the two adjacent action units are separated by the middle cover (13), and one end of the middle cover (13) is provided with a blocking part (132) for separating the moving contact (51) from the thermal tripping mechanism (8).

4. A miniature circuit breaker according to claim 1, wherein: at least one end joint of shell (1) has insulating barrier (14), insulating barrier (14) include connecting plate (141) and division board (142) of setting on connecting plate (141), connecting plate (141) and shell (1) joint, division board (142) are corresponding to between two binding post (2) of two adjacent circuit breakers with one end.

5. A miniature circuit breaker according to claim 4, wherein: and the isolating plate (142) is provided with a knock-off structure, and when at least two circuit breakers are connected in series, the adjacent two insulating isolating plates (14) are communicated by breaking the knock-off structure.

6. A miniature circuit breaker according to claim 5, wherein: the connecting row connectors corresponding to the wiring terminals (2) are further arranged at two ends of the shell (1) respectively, the connecting row connectors are located above the wiring ports (105), the knocking-off structures correspond to the connecting row connectors, the knocking-off structures are breaking grooves (1422) formed in the end portions, close to one ends, of the isolation plates (142), the length of the isolation plates (142) is larger than that of the connecting plates (141), the connecting plates (141) do not shield the connecting row connectors, and the knocking-off structures arranged on the isolation plates (142) in a breaking mode can enable the connecting row connectors of two adjacent miniature circuit breakers to be communicated.

7. A miniature circuit breaker according to claim 1, wherein: the operating mechanism (4) comprises a lever (41), a contact support (43), a lock catch (45), a jump buckle (44), a tripping hook (47), a torsion spring (46) and a mechanism main spring (42), wherein the lever (41) is rotatably assembled in the shell (1), the contact support (43) is rotatably assembled on the lever (41), a movable contact (51) is rotatably assembled on the contact support (43), the lock catch (45) and the jump buckle (44) are respectively rotatably assembled on the lever (41), the lock catch (45) is in hasp fit with one end of the jump buckle (44), the other end of the lock catch (45) is opposite to the electromagnetic tripping mechanism (7), the tripping hook (47) is connected with the other end of the lock catch (45) and opposite to the thermal tripping mechanism (8), the torsion spring (46) is rotatably assembled on the contact support (43), and two ends of the torsion spring (46) are respectively abutted and matched with the contact support (43) and the lever (41), two ends of the mechanism main spring (42) are respectively connected with the lever (41) and the shell (1).

8. A miniature circuit breaker according to claim 3, wherein: arc extinguishing system (6) still include run-on angle (62), flash wall (63) and permanent magnet (64), the one end of blocking part (132) is kept away from in lid (13) is fixed in explosion chamber (61), and run-on angle (62) are equipped with the one end setting of blocking part (132) along well lid (13), and flash wall (63) set up between explosion chamber (61) and blocking part (132), and permanent magnet (64) set up one side of explosion chamber (61) back to at run-on angle (62).

9. A miniature circuit breaker according to claim 8, wherein: fixed muscle (1311) and boss structure (1315) are equipped with in the positive and negative both sides protrusion of well lid (13), fixed muscle (1311) are used for the arc extinguishing bars piece of cooperation fixed explosion chamber (61), and boss structure (1315) are fixed with the groove structure cooperation of flash barrier (63).

10. A miniature circuit breaker according to claim 1, wherein: the thermal tripping mechanism (8) comprises a bimetallic strip, one end of the bimetallic strip is fixed on the shell (1), and the other end of the bimetallic strip is opposite to the operating mechanism (4).

Images