WO2016078482A1

WO2016078482A1 - Multi-pole double-breakpoint plastic-shell circuit breaker

Info

Publication number: WO2016078482A1
Application number: PCT/CN2015/091532
Authority: WO
Inventors: 冯伟通; 李孔伏; 顾翔
Original assignee: 浙江正泰电器股份有限公司
Priority date: 2014-11-20
Filing date: 2015-10-09
Publication date: 2016-05-26
Also published as: EP3223296A1; EP3223296A4; IL252420B; CN204375671U; IL252420A0

Abstract

A multi-pole double-breakpoint plastic-shell circuit breaker. Multiple single-pole circuit breaking unit (30) are disposed inside an insulation shell,. A contact system and a matching arc-extinguishing system are disposed inside a unit plastic-shell of each single-pole circuit breaking unit (30). A contact system of each pole comprises two fixed contacts (14, 16) arranged opposite and one bridge-shaped movable contact (20), and each bridge-shaped movable contact (20) is installed on one contact support (17, 18). Each arc-extinguishing system comprises two symmetrically disposed arc-extinguishing chambers (6, 9). Outer rings of multiple roller bearings (19) are fixedly installed on a separating wall (g) by using a bearing mechanism. An inner ring of a roller bearing (19) is directly linked to contact supports (17, 18) in a manner of interference fit. Two adjacent contact supports (17, 18) are directly inserted and linked in a manner of interference fit. One cylindrical cavity (b) for receiving the contact supports (17, 18) is disposed between two arc-extinguishing chambers (6, 9) of the unit plastic-shell of each single-pole circuit breaking unit (30). By means of the multi-pole double-breakpoint plastic-shell circuit breaker, not only high sensitivity and high precision of rotation supported by each contact are ensured, but also precision and synchronization requirements can be ensured through processing relying on precision of only a mold.

Description

Multi-pole double breakpoint molded case circuit breaker

Technical field

The invention relates to the field of low-voltage electrical appliances, in particular to a multi-pole double-breakpoint molded case circuit breaker.

Background technique

Multi-pole double breakpoint molded case circuit breaker is a widely used device type circuit breaker in low voltage circuit breaker. All its components are installed in a box type plastic case, and its molded insulated plastic case is generally The utility model comprises a molded case base as a shell seat and a molded case cover plate matched with the molded case base, and the cavity is formed by the molded case base and the molded case cover. Within the molded insulative housing, a plurality of poles are provided with a contact system for performing a circuit closing and opening operation and a circuit breaking unit for the arc extinguishing system. A typical configuration is that each of the breaking units has a box of molded plastic of the same size, and the contacts of the same pole, the arc extinguishing chamber and its associated components are mounted in the box. A plurality of breaking units having the same configuration are placed side by side in the molded case base, a common operating mechanism is disposed on each of the breaking units, and the molded case cover encloses each of the breaking units and the operating mechanism in the chamber To form a multi-pole circuit breaker. Each pole contact system comprises two static contact parts and a two-contact dynamic contact bridge capable of contacting or separating the static contact parts of the pole under the driving of the operating mechanism, the double-break bridge-shaped moving contact and Two oppositely placed static contacts are mated. The two arc extinguishing chambers of each pole include arc chutes symmetrically installed in the two arc extinguishing chambers. Since the user requires that the circuit breaker be turned on, the breaking capacity and the thermal stability are good, the components that constitute the contact, the arc extinguishing system, the tripping, and the operating mechanism are complicated, and the static and dynamic connections formed by the assembly thereof are assembled. The mating part is complicated and complicated. Therefore, the breaking capacity of the circuit breaker, the synchronism of the action of each pole contact, the contact pressure of the moving contact and the static contact, the breaking and closing speed, the reliability and the reliability of the product, and the structure thereof Whether the design is reasonable or not, the precision of the processing and assembly of the parts is very high, and the processing and assembly precision of the parts is directly related to the production efficiency and manufacturing cost. Starting from the requirements of improving production efficiency, reducing manufacturing costs and facilitating large-scale automated production, under the premise of ensuring product quality and performance requirements, the processing and assembly precision of components are reduced as much as possible, and the process of assembly and debugging is simplified as much as possible. Design important issues to be addressed.

There is also a multi-pole circuit breaker in the prior art, which has only a single-pole breaking unit. The bridge contact of the circuit breaker is supported by a rotatable rod-shaped block which extends laterally from the center of the box of the breaking unit. Out and inserted between the two large side surfaces of the box, can be moved parallel to the center of the two large surfaces. The rods of different juxtaposed units are coupled with the operating mechanism by two parallel links. The common operating mechanism is fixed to the upper portion of the breaking unit in the middle of the circuit breaker, and has two metal flanges for supporting the crank bearing and a connecting rod for driving the bottom of the crank. The action of the operating mechanism drives the two links through the rotation of the crank, thereby transmitting the rods to the poles, so that the pole moving contacts are opened or closed. Since the bridge moving contact is floatingly mounted on the rod-shaped block, the mechanical connection is achieved only by the two connecting rods between the different rod-shaped blocks, thereby causing the following problem: due to the elongated structure of the two connecting rods, The relative deformation between the pole-shaped blocks is large, and the deformation directly affects the synchronization of the moving of the bridge-shaped moving contact; The rotation accuracy of the body is very low and the slender structure does not have the function of providing the rotation precision to each rod block. Therefore, the rotation precision of each rod block must be ensured by the gap between the rod block and the box, but manufacturing The defect of the error needs to be compensated by means of the gap described, which in turn destroys the rotational accuracy of the rod-shaped block. For this purpose, the rod-shaped block must be mounted in the box with a certain gap, that is to say, the rod-shaped block The gap between the box and the box cannot be made small, but the larger gap cannot achieve high-precision rotation of each rod block; the airflow generated during the disconnection is inevitably discharged from the gap between the rod block and the box. However, such a high-temperature airflow having a great impact force inevitably causes random damage to the gap, so that the rotation accuracy of the rod-shaped block easily becomes unstable with the use time of the product, and is even easy to fail. . However, the rotation accuracy of each of the rod-shaped blocks is the key to ensure the synchronism of the breaking and closing actions between the respective contacts and the contact pressure performance of the moving and static contacts when closing, and therefore, such prior art is related to the related components. The processing precision and assembly precision are very high. The synchronization of the motion between the pole contacts, the contact pressure performance between the pole contacts, the breaking capacity of the contacts, the reliability and service life of the products have yet to be improved. .

There is also a multi-pole circuit breaker in the prior art, which only has a multi-stage breaking unit. The moving contacts of the plurality of breaking units of the circuit breaker are arranged on the same rotating shaft through the contact support, and the integrated design shaft passes through the bearing cover. And the bearing seat is installed on the partition wall of the large molded case. The bridge moving contact is floatingly mounted on the contact support on the rotating shaft, and the contact supports a rigid mechanical connection with the rotating shaft, and the movement consistency of each pole contact and the rotating shaft is improved, and the manufacturing error is overcome The difference between the overtravel between the contact bridge and the two static contacts can be compensated. However, the new problem is: to ensure the ideal fit between the rigid integrated shaft and the large molded case, it is necessary to improve the processing of the parts. Accuracy requirements, and must ensure that the hard friction surface of the joint movement between the rotating shaft and the bearing cap and the bearing housing has high wear resistance. Otherwise, the rotation of the rotating shaft and the failure of the precision of the components will still cause the relative polar contacts to be opposite. The unsynchronization of the action of the static contact; since it is difficult to ensure the high precision of the part processing in large-scale production, and it leads to an increase in cost and a reduction in production efficiency, it is necessary to increase the relationship between the rotating shaft and the bearing cap and the bearing housing. Cooperate with the gap, otherwise there will be a problem that the rotation of the shaft is not flexible, which directly affects the breaking and closing speed of the contact, and the increase of the matching clearance will affect the return of the shaft. Accuracy.

It is a good idea to solve the problems encountered in multi-pole double-breakpoint molded case circuit breakers by using the advantages of high rotation precision and flexible rotation of rolling bearings. However, in the specific implementation, a series of technical problems need to be solved, such as: How to realize the structure that the closed inner ring of the rolling bearing is conveniently mounted to the middle of the two middle and middle fine rotating shafts, and how the rotary structure composed of the contact support and the rolling bearing ensures the rigidity, the shape and the position precision and the rotation precision, and the rolling bearing is composed of a plurality of rolling bearings The complex structure composed of contact support, moving contact, breaking unit and molded case can meet the technical requirements of easy processing and assembly debugging, few parts, low manufacturing cost and suitable for mass production.

Summary of the invention

The object of the present invention is to overcome the defects of the prior art and provide a novel multi-pole double-breakpoint molded case circuit breaker, which adopts a reliable and relatively simple mechanism, and reduces the inevitable coaxiality due to the connection link. The influence of the stiffness and strength deterioration factors is beneficial to the synchronization between the contacts, achieving reliable mechanical connection and transmission between the different pole breaking units, improving the performance and reliability of the product, and For processing and debugging.

In order to achieve the above object, the present invention provides the following specific technical solutions.

A multi-pole double-breakpoint molded case circuit breaker is provided with a plurality of chambers 22 partitioned by partition walls g for accommodating a plurality of single-pole breaking units 30, each of which has a unit Molded case, each unit molded case is provided with a contact system for performing the closing and breaking of the main circuit of the pole and a matching arc extinguishing system, and the contact system of each pole includes two oppositely disposed

static contacts

14, 16 and A bridge movable contact 20 capable of simultaneously closing and breaking with the two

stationary contacts

14, 16 respectively, each of the bridge movable contacts 20 being mounted on a contact support in an elastic overtravel manner, the circuit breaker The operating mechanism 4 drives the contacts of the plurality of single-pole breaking units 30 to support synchronous rotation by a driving mechanism, and each arc extinguishing system includes two

arc extinguishing chambers

6, 9 symmetrically disposed in the unit molded case, two static The

contacts

14, 16 are respectively disposed in the arc extinguishing regions of the two

arc extinguishing chambers

6, 9, the multi-pole double-breakpoint molded case circuit breaker further includes a plurality of rolling bearings 19, and the outer ring of the rolling bearing 19 is fixed by a bearing mechanism Mounted on the partition wall g, the inner ring of the rolling bearing 19 and the contact support The static matching mode is directly connected, and the adjacent two contact supports are directly plugged and connected in a static fit manner; the two

arc extinguishing chambers

6 and 9 of the unit molded case of each single-pole breaking unit 30 are described. There is a cylindrical chamber b supported by the receiving contact, the cylindrical chamber b comprises a circular arc surface a, and two partitions are respectively arranged between the cylindrical chamber b and the two

arc extinguishing chambers

6, 9 The

arc walls

6a, 9a are respectively provided with two windows penetrating on the two

arc walls

6a and 9a, and the two ends of the bridge movable contact 20 extend from the two windows to the two

arc extinguishing chambers

6, 9 respectively. The contact support includes an outer cylindrical surface 183 that cooperates with the circular arc surface a and has a matching gap between the outer cylindrical surface 183 and the circular arc surface a.

Further, on one end of the contact of one of the adjacent two single-pole breaking units 30, an integrally formed connecting shaft coaxial with the outer cylindrical surface 183 supported by the contact is disposed along the axial direction X thereof; The inner ring of the rolling bearing 19 is fitted on the connecting shaft in a static fit manner, and is connected at the end of the contact support of the other single-pole breaking unit 30 along the axial direction X thereof in a static fit with the connecting shaft. The shaft hole 100 is coupled, and the arrangement and coupling of the connecting shaft and the connecting shaft hole 100 satisfy the condition that the outer cylindrical surface 183 supported by each contact is coaxial.

Further, the circuit breaker includes three single-pole breaking units 30 arranged side by side, and the two ends of the three single-pole breaking units in the middle of the contact support of the single-pole breaking unit 30 are disposed along the axial direction X thereof. The outer cylindrical surface 183 of the contact support is coaxially integrated with the connecting shaft, and the inner rings of the two rolling bearings 19 are respectively arranged in a static fit manner on the connecting shafts at both ends of the intermediate contact support; in the other two single-pole breaking units One end of the contact support of 30 is provided along its axial direction X with a connecting shaft hole 100 that is connected in a static fit with the connecting shaft, and the connecting shaft and the connecting shaft hole 100 are arranged and coupled to satisfy the support of each contact. The condition that the cylindrical surface 183 is coaxial.

Further, the connecting shaft comprises a rolling bearing connecting section 181 which is connected with the inner ring of the rolling bearing 19 in a static fit manner and a contact supporting connecting section 180 which cooperates with the connecting shaft hole 100. The diameter of the contact supporting connecting section 180 is smaller than that of the rolling bearing The diameter of the connecting section 181; the contact support is integrally formed by using a bulk molding compound or a sheet molding compound.

Further, the contact-supported contact support connecting portion 180 has a polygonal cross section, and the contact-supported connecting shaft hole 100 has a cross-section that is a polygon matching the cross-section of the contact supporting connecting portion 180.

Further, the contact support connecting section 180 of the contact support 18 is provided with a rolling bearing 19 The inner ring contacts the mating shoulder 184, and the outer end surface of the connecting shaft hole 100 supported by the contact is provided with a mounting surface 185 which is in contact with the inner ring of the rolling bearing 19.

Further, the driving mechanism comprises two through shafts 7 arranged in parallel with each other, and two small through holes 18a are respectively arranged along the axial direction X thereof on the respective contact supports, and the two through shafts 7 respectively pass through the respective contact supports. The upper two small through holes 18a are fixedly coupled to the contact coupling members of the operating mechanism 4, and the rotation axes of the contact coupling members are coaxial with the axes of the outer cylindrical surfaces 183 supported by the respective contacts.

Further, the driving mechanism includes two protruding shafts disposed on the contact coupling members of the operating mechanism 4, and two small through holes 18a disposed on the contact supports of the contact coupling members of the operating mechanisms 4, The two male shafts are respectively coupled to the two small through holes 18a, and the rotation axis of the contact coupling member is coaxial with the axis of the outer cylindrical surface 183 supported by the contacts.

Further, the bearing mechanism comprises a fixing plate 3 having a bearing half hole, a bearing seat f having a bearing half hole disposed on the partition wall g, the fixing plate 3 is fixedly coupled with the bearing seat f and the two bearing half holes are butted The outer ring of the rolling bearing 19 is mounted in a static fit with two butted bearing half holes.

Further, the unit molded cases of each single-pole breaking unit 30 respectively include a first small side shell 10, a second small side shell 11, a third small side shell 12, and a fourth small side shell 13, the first small The side shell plate 10 is assembled with the second small side shell plate 11 to form a first arc extinguishing chamber 6 and a first semi-cylindrical chamber, and the third small side shell plate 12 and the fourth small side shell plate 13 are oppositely assembled to form a second The arc extinguishing chamber 9 and the second semi-cylindrical chamber, the first arcing chamber 6 is provided with a first engaging portion c1 and a second engaging portion c2, and the second arc extinguishing chamber 9 is provided with a third engaging portion The d1 and the fourth latching portion d2, the first latching portion c1 and the third latching portion d1 are snap-fitted to form a fixed coupling, and the second latching portion c2 and the fourth latching portion d2 are snap-fitted to form a fixed coupling. The semi-cylindrical chamber and the second semi-cylindrical chamber are assembled into a cylindrical chamber b by a fixed coupling of the first quenching chamber 6 and the second quenching chamber 9.

Further, the unit molded case of each single-pole breaking unit 30 includes a first large side shell 23 and a second large side shell 24, and the first large side shell 23 and the second large side shell 24 are oppositely assembled to form two The arc

extinguishing chambers

6, 9 and the cylindrical chamber b.

By adopting any of the above technical solutions of the present invention, the direct connection between the contact support and the contact support and the rolling bearing reduces the influence of the inconsistent coaxiality, rigidity and strength deterioration factors due to the connection link. At the same time, it facilitates the synchronization between the contacts, achieves reliable mechanical connection and transmission between different pole breaking units, and improves product performance and reliability. The reasonable design of the rolling bearing and the partition wall, the contact support and the cylindrical chamber of the arc extinguishing chamber makes it easier to ensure the accuracy of the slewing bearing and the rigidity of the shaft load, reduce the manufacturing precision and cost of the components of the moving contact bridge assembly, and is easy to process. And debugging, improve the performance and production efficiency of the dynamic contact bridge assembly; solve the defects such as strength requirements, temperature resistance requirements and insulation performance of the dynamic contact bridge assembly in the long-term operation of the circuit breaker.

DRAWINGS

The advantages and features of the present invention will become more apparent from the description of the embodiments illustrated in the appended claims

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is an overall exploded view of a multi-pole double-breakpoint molded case circuit breaker of the present invention, showing an overall exploded structure of a three-pole double-breakpoint molded case circuit breaker.

2 is a molded insulated housing 21 of the multi-pole double-breakpoint molded case circuit breaker of the present invention shown in FIG. Schematic diagram of the structure, the housing 21 shown in the figure supports a three-pole double-breakpoint molded case circuit breaker.

3 is an exploded view of the three-pole breaking unit of the multi-pole double-breakpoint molded case circuit breaker of the present invention shown in FIG. 1, and the single-pole breaking unit 30 shown in the drawing adopts the configuration of the first embodiment.

Figure 4 is an assembled, isometric view of the breaking unit of the first embodiment of one of the poles of the multi-pole double-breakpoint molded case circuit breaker of the present invention shown in Figure 3, the single-pole open circuit of the first embodiment shown in the drawing The two arc extinguishing chambers of unit 30 are detachable.

FIG. 5 is a schematic view showing the internal structure of one of the two detachable arc extinguishing chambers shown in FIG.

Fig. 6 is a schematic view showing the internal structure of the other arc extinguishing chamber 9 of the two detachable arc extinguishing chambers shown in Fig. 4.

Figure 7 is a schematic perspective view showing the assembly of the breaking unit of the second embodiment of one of the poles of the multi-pole double-breakpoint molded case circuit breaker of the present invention, and two of the single-pole breaking units 30 of the second embodiment shown in the drawing. The arc chamber is not separable.

Fig. 8 is a view showing the internal structure of the single-pole breaking unit 30 of the second embodiment shown in Fig. 7.

FIG. 9 is a schematic structural view showing the assembly of the pole contacts of the multi-pole double-breakpoint molded case circuit breaker of the present invention shown in FIG. 1 , showing the support by one contact 17 and the support of two contacts 18 . The two rolling bearings 19 are assembled to form a specific structure of the three-pole dynamic contact bridge assembly 8.

Figure 10 is an exploded view of the three contact supports and two rolling bearings 19 shown in Figure 9.

11-13 are structural diagrams of the parts of the contact support 18 of the three contact supports shown in Fig. 9, wherein:

Figure 11 is a front view of the contact support 18 plane;

Figure 12 is a plan right side view of Figure 11;

Figure 13 is a plan left side view of Figure 11;

Figure 14 is a further embodiment of a three-pole dynamic contact bridge assembly 8 of the present invention.

detailed description

The specific embodiment of the multi-pole double-breakpoint molded case circuit breaker of the present invention will be further described below with reference to the embodiments given in FIGS. 1 to 14. The following description of the embodiment of the circuit breaker of the present invention is by way of non-limiting example only.

The embodiment of the overall structural exploded view of FIG. 1 shows a three-pole double-breakpoint molded case circuit breaker including an upper cover 1, a middle cover 2, an operating mechanism 4, a handle 5, and a housing 21. The housing 21 and the upper cover 2 and the upper cover 1 fitted thereto form an insulating housing of the multi-pole double-break molded case circuit breaker, and the insulating housing is also called a large molded case. The insulative housings are made of PBT or PA66 engineering plastic and have a generally hexahedral shape. The inner member of the multi-pole double-breakpoint molded case circuit breaker is installed in a large plastic case which is composed of the shell seat 21 and the middle cover 2, and the upper part of the middle cover 2 of the large molded case is sealed by the upper cover 1, and the handle 5 is from the middle The hole in the cover 2 is pierced.

Referring to FIG. 1 to FIG. 3, a plurality of chambers 22 for partitioning a plurality of single-pole breaking units 30 are formed in the insulating casing, that is, a pole is installed in each of the chambers 22 Single pole breaking unit 30. Each of the single-pole breaking units 30 has a unit molded case, the unit molded case has a substantially hexahedral shape, and the unit molded case is also referred to as a small molded case, and each unit molded case is provided with a touch for performing the closing and breaking of the main circuit of the pole. The head system and the associated arc extinguishing system, or the same pole contact system and arc extinguishing system, are enclosed within the small molded casing. For a double-breakpoint molded case circuit breaker, the contact system of each pole necessarily includes two oppositely disposed

stationary contacts

14, 16, and one that can simultaneously close and break with the two

stationary contacts

14, 16 respectively. The bridge moving contact 20, in particular, the bridge moving contact 20 is simultaneously rotated with the two

stationary contacts

14, 16 or simultaneously with the two

stationary contacts

14, 16 and is blocked by the circuit breaker when closed. The main circuit of the control is turned on, and the main circuit is turned off when the line is disconnected. For a double-breakpoint molded case circuit breaker, the arc extinguishing system of each pole needs to include two

arc extinguishing chambers

6, 9 symmetrically disposed in the small molded case, and the two

arc chutes

15a, 15b are respectively disposed at In the two

arc extinguishing chambers

6, 9, two

static contacts

14, 16 are respectively arranged in the arc extinguishing regions of the two

arc extinguishing chambers

6, 9 in the arc extinguishing region where the two

stationary contacts

14, 16 are located. The bridge moving contacts 20 are respectively closed and divided regions of the two

stationary contacts

14, 16. Each of the bridge movable contacts 20 is mounted on a

contact support

17 or 18 in an elastic overtravel manner to form the movable contact bridge assembly 40. The structure of the elastic overtravel is realized as shown in FIG. The elastic overtravel assembly 20a includes an overtravel spring through which the bridge moving contact 20 is mounted within the large through hole 182 of the

contact support

17 or 18. An operating mechanism 4 shared by a plurality of poles is disposed above the intermediate one-pole breaking unit, and the operating mechanism 4 drives the respective contact supports 17, 18 to rotate synchronously by the driving mechanism. The mounting structure of the operating mechanism 4 can be in various ways, usually a structure in which a frame (not shown) of the operating mechanism is fixedly coupled to the housing 21 to facilitate assembly and debugging. The operating mechanism of such a circuit breaker has a driving mechanism for driving the rotation of the contact. The driving mechanism necessarily includes a contact coupling member (not shown), and the operating mechanism passes through the contact coupling member and the bridge shape. The movable contact coupling (including direct coupling and indirect coupling) realizes linkage between the contact coupling member and its bridge movable contact, that is, the closing and breaking action of the contact system is driven by the contact coupling member.

The improvement and innovation of the present invention will be further described below with reference to the accompanying drawings. The core of the present invention is to solve the problem of how the operating mechanism 4 simultaneously drives the rotation of the contact supports 17, 18 of the poles, and how to ensure that the contacts of the poles support the rotation of 17,18. Synchronization and flexibility, and how to get an optimized structure that is easy to scale, efficient, and cost-effective. Reduce the manufacturing precision and cost of the components of the dynamic contact bridge assembly, improve the full performance of the dynamic contact bridge assembly and improve the production efficiency; solve the strength requirements, temperature resistance requirements, insulation of the dynamic contact bridge assembly in the long-term operation of the circuit breaker Defects such as performance.

Referring to FIGS. 2 to 14, the multi-pole double-breakpoint molded case circuit breaker of the present invention further includes a plurality of rolling bearings 19, and an outer ring of the rolling bearing 19 is fixedly mounted on the partition wall g by a bearing mechanism, and an inner ring of the rolling bearing 19 Directly coupled with the

contact support

17 or 18 in a static fit, the adjacent two contact supports 17 and/or 18 are directly plugged in a static fit. With such a structure, the plurality of rolling bearings 19 and the

contact holders

17 or 18 are formed into the movable contact bridge assembly 8 as shown in FIG. The manner of static fit means that two mutually mating parts are combined to form a non-relatively movable joint, including an interference fit or a transition fit.

Between the two

arc extinguishing chambers

6, 9 of the unit molded case of each single-pole breaking unit 30, a cylindrical chamber b for accommodating the

contact support

17 or 18 is provided, and the cylindrical chamber b includes a circle. The arc surface a is provided with two arc-shaped

walls

6a, 9a between the cylindrical chamber b and the two arc-extinguishing

chambers

6, 9 respectively, and two through-holes are respectively provided on the two arc-shaped

walls

6a, 9a. a window, two ends of the bridge movable contact 20 respectively extend from the two windows into the two

arc extinguishing chambers

6, 9; the contact supports 17, 18 include an outer cylindrical surface 183, the outer cylindrical surface 183 The arcuate surface a is fitted, and a matching gap is provided between the outer cylindrical surface 183 and the circular arc surface a. It should be understood that the so-called mating gap means that the gap between the outer cylindrical surface 183 of the

contact support

17, 18 and the arc surface a on the small molded shell of the single-pole breaking unit 30 has a matching function, and the contact is ensured. The supports 17 and 18 are flexibly rotatable therein, and the gap is small enough to prevent high pressure gas from leaking into the circular chamber b in the two arc extinguishing chambers. Of course, the matching gap of the present invention not only prevents the high-pressure gas in the arc extinguishing chamber from leaking into the cylindrical chamber, but also has the function of improving the rotation precision and rigidity supported by the contact, and the prior art "small gap" or "certain" The function of the gap is mainly to prevent the high-pressure gas in the arc extinguishing chamber from leaking into the circular chamber, or to compensate for irregularities in manufacturing and installation, so that the rod-shaped block can be slightly moved in other directions. In order to obtain a more desirable fit, a preferred embodiment is that the axes of the outer cylindrical faces 183 of the respective contact supports 17, 18, the axes of the respective contact support connecting segments 180, and the axes of the respective connecting shaft holes 100 are mutually Coaxial.

The movable bridge assembly 8 is composed of a plurality of contact-supporting direct-plug connections on one end of the contact-supported end of one of the two single-pole breaking units 30, along the axis supported by the contacts An integrally formed connecting shaft is provided to the X, and at one end of the contact support of the other single-pole breaking unit 30, a connecting shaft hole 100 corresponding to the connecting shaft is provided along the contact supporting axial direction X, and the shaft hole 100 is connected to the static The manner of mating with the connecting shaft; the connecting shaft supported by the adjacent two contacts is provided with a rolling bearing 19, and the inner ring of the rolling bearing 19 is directly coupled with the connecting shaft in a static fit manner. The specific structure supported by the contacts can be various. A preferred structure is shown in FIGS. 9-13, which includes two different shapes of the contact support 18 and the contact support 17. At one end of the contact support 18, a rolling bearing connecting section 181 coaxial with the outer cylindrical surface 183 is provided along its axial direction X, and an end of the rolling bearing connecting section 181 is provided with an extension along the axial direction X. The contact supports the connecting section 180. The connecting shaft includes a rolling bearing connecting section 181 and a contact supporting connecting section 180. The rolling bearing connecting section 181 and the contact supporting connecting section 180 are integrally formed with the contact support 18, and the contact supports the diameter of the connecting section 180. Less than the diameter of the rolling bearing connecting section 181, the inner ring of the rolling bearing 19 is fitted over the rolling bearing connecting section 181 in a form-fitting manner. The contact support 17 differs from the contact support 18 in that the contact support 17 does not have the above-described structure of the rolling bearing connection section 181 and the contact support connection section 180. The contact support 17 and the contact support 18 have the same structure: at the other end of the

contact support

17, 18, along its axial direction X is provided with contact support for accommodating adjacent contact supports 17 or 18 The connecting shaft hole 100 of the connecting portion 180 is connected to the contact supporting connecting portion 180 in an interference fit manner, and the setting and coupling of the contact supporting connecting portion 180 and the connecting shaft hole 100 are satisfied to support each contact The outer cylindrical surface 183 of 17, 18 is coaxial; a large through hole 182 for accommodating the radial movement of the bridge movable contact 20 is provided on the outer cylindrical surface 183 of the

contact support

17,18. The two ends of the bridge movable contact 20 installed in the large through hole 182 through the elastic overtravel assembly 20a are symmetrically protruded outside the outer cylindrical surface 183, respectively, and the two ends of the extension are respectively from the two of the single pole breaking unit 30 The two windows on the

arcuate walls

6a, 9a extend into the interior of the two

arc extinguishing chambers

6, 9. Another more preferred manner is shown in FIG. 14, the circuit breaker includes three single-pole breaking units 30 arranged side by side, each single-pole breaking unit 30 includes one contact support, and three contacts support direct insertion. Connected to form the dynamic contact bridge assembly 8, at both ends of the contact support of the single-pole breaking unit 30 in the middle, and an integral connecting shaft coaxial with the outer cylindrical surface 183 supported by the contact is disposed along the axial direction X thereof. The inner rings of the two rolling bearings 19 are respectively fitted on the connecting shafts of the two ends of the intermediate contact support in a static fit manner; at the end supported by the contacts of the other two single-pole breaking units 30, the connecting and connecting along the axial direction X thereof The shaft is connected to the shaft hole 100 in a static fit manner, and is connected The arrangement and coupling of the shaft and the connecting shaft hole 100 satisfy the condition that the outer cylindrical surface 183 supported by each contact is coaxial, and the outer cylindrical surface 183 of the movable contact bridge assembly 8 of the present embodiment is more coaxial. Of course, the connecting shaft of the present embodiment may also include a rolling bearing connecting section 181 and a contact supporting connecting section 180. Since there is a force transmission of the coupling between the contact supporting connecting section 180 and the connecting shaft hole 100, in order to make the static fit between them more stable and reliable and have stronger rigidity, a preferred structural solution is: The contact support connecting section 180 of the contact support 18 has a polygonal or elliptical or other non-circular shaped structure. The cross-section of the connecting shaft hole 100 of the

contact support

17, 18 is a contact with the contact. A polygonal or elliptical or other non-circular shaped structure that matches the cross-section of the connecting section 180 is supported. In order to make the static fit between the rolling bearing connecting section 181 and the inner ring of the rolling bearing 19 more stable and reliable, preventing the inner ring of the rolling bearing 19 from slipping in the axial direction of the rolling bearing connecting section 181, a preferred solution is that the contact The contact support connecting section 180 of the support 18 is provided with a shoulder 184 which is in contact with the inner ring of the rolling bearing 19, and the outer end surface of the connecting shaft hole 100 of the

contact support

17, 18 is provided with the rolling bearing 19. The inner ring is in contact with the mating mounting surface 185. After the rolling bearing 19 is mounted on the contact support, the two end faces of the inner ring of the rolling bearing 19 abut against the shoulder 184 and the mounting surface 185, respectively, to prevent axial movement of the rolling bearing 19. . Each

contact support

17, 18 is made of DMC (bump molding compound) or SMC (sheet molding compound) engineering molded plastic to improve the overall heat resistance of the circuit breaker. During installation, through the metal rolling bearing 19 through the interference fit of the connecting shaft of the contact support 18, the two sides e of the connecting shaft hole inserted into the contact support 17 are used, and the axial center of the integral rotating shaft is realized by the side e Positioning, and then connecting the respective contact supports 17 and 18 with two through shafts 7 to ensure the rigidity and positioning of the integrally assembled moving contact bridge assembly 8, and then fixing the rotating shaft to the insulating plastic shell through the fixing plate 3 and the metal rolling bearing 19 The bearing half of the bearing half hole realizes the center positioning of the rotating shaft, and the contact sway does not occur.

The driving mechanism connected to the operating mechanism 4 comprises two through shafts 7 arranged in parallel with each other, and two small through holes 18a are respectively arranged along the axial direction X of the respective contact supports 17, 18, respectively. After passing through the two small through holes 18a of the respective contact supports 17, 18, they are fixedly coupled with the contact couplings of the operating mechanism 4, and satisfy the rotation axis of the contact coupling members and the respective contact supports 17, 18 The axis of the outer cylindrical surface 183 is coaxial, that is, coaxial with the axis of rotation of the respective contact supports 17, 18. The use of two through-axis series pole contact support ensures the synchronization and alignment of the pole contacts, improves the rigidity and strength of the integral dynamic bridge assembly, and ensures uniform force support of each pole contact. Consistently, it provides a solution for increasing the rated current of the circuit breaker, solves the problem of looseness of the contact support after multiple operations of the movable contact bridge assembly, and the synchronization problem occurs, and the installation is more flexible and convenient, and the assembly process can be simplified. Since the dynamic contact bridge assembly 8 of the present invention has the above special structure, it has high rotation precision and rotational rigidity, or the mutual precision and rigidity of the mutual contact between the respective contact supports 17, 18 are high, and thus It is difficult to imagine that as long as the operating mechanism 4 drives one of the contacts to support 17 or 18 rotation, the other contact supports 17, 18 will also rotate at the same time, so the following structure (not shown) can be substituted for the above-mentioned figures. The structure of the embodiment: the driving mechanism comprises two protruding shafts disposed on the contact couplings of the operating mechanism 4, and two of the contact supports 17 or 18 disposed adjacent to the contact couplings of the operating mechanisms 4. a small through hole 18a, the two protruding shafts are respectively plugged and coupled with the two small through holes 18a, and satisfy the axis of rotation of the contact coupling member and the axis of the outer cylindrical surface 183 of the

contact support

17 or 18 Coaxial. Obviously, this alternative cannot be adapted in the prior art described above because of the lack of coaxiality and rotational accuracy described in the prior art. It is not possible to adopt this alternative, or if this alternative is adopted, the synchronization of the motions supported by the contacts will be significantly reduced. Obviously, the above alternatives that simplify the structure can be employed, and are themselves one of the beneficial technical effects of the present invention.

Referring to Figures 1, 2, 9 and 10, the bearing mechanism comprises a fixing plate 3 having a bearing half hole, and a bearing seat f having a bearing half hole provided on the partition wall g, and the fixing plate 3 is fixedly coupled with the bearing housing f and The two bearing half holes are butted, and the outer ring of the rolling bearing 19 is mounted in a static fit manner with the two butted bearing half holes. It should be understood that, due to the use of the rolling bearing 19, the "manufacturing and installation irregularities" can be compensated by the fixed coupling of the fixing plate 3 to the bearing housing f, but unlike the prior art, the compensation of the present invention, The principle of achieving the coaxiality and the rotation accuracy is not caused, and the principle of achieving the effect is that the radial and axial positions of the rolling bearing 19 can be finely adjusted when the fixing plate 3 is fixedly coupled with the bearing housing f. By this fine adjustment structure, it is possible to establish a stable and reliable fixed connection between the outer ring of the rolling bearing 19 and the partition wall g, and to ensure high-precision and flexible rotation of the inner ring of the rolling bearing 19.

Referring to FIG. 1 to FIG. 6 , the small molded case of the single-pole breaking unit 30 adopts a split structure, that is, the small molded shells of the single-pole breaking units 30 respectively include a first small side shell 10 and a first Two small side shell plates 11, a third small side shell plate 12, and a fourth small side shell plate 13, the first small side shell plate 10 and the second small side shell plate 11 are oppositely assembled to form an arc extinguishing chamber 6 and a half cylinder The shape chamber, the third small side shell 12 and the fourth small side shell 13 are oppositely assembled to form another arc extinguishing chamber 9 and a half cylindrical chamber, and the first arcing chamber 6 is provided with a first engaging portion c1 The second engaging portion c1 is provided with a third engaging portion d1 and a fourth engaging portion d2. The first engaging portion c1 and the third engaging portion d1 are snap-fitted to form a fixed joint. The second engaging portion c2 is engaged with the fourth engaging portion d2 to form a fixed coupling, and the two half cylindrical chambers are assembled into the entire cylindrical chamber b through the two fixed couplings, and the two arc extinguishing chambers 6 And 9 are independently separable. A further advantageous effect of the present invention is that the small molded case of the single-pole breaking unit 30 of the present invention can also adopt a unitary structure with respect to the integral rotating shaft, which can be replaced with the separated structure, but it has a split structure. It is simpler and ensures a precise fit between the arcuate surface a on the small molded casing and the outer cylindrical surface 183 of the

contact support

17,18. The overall structure is as shown in FIG. 7 to FIG. 8 : the small molded shells of the single-pole breaking units 30 respectively include a first large side shell 23 and a second large side shell 24, and the first large side shell. The plate 23 is assembled with the second large side shell plate 24 to form two

arc extinguishing chambers

6, 9 and a cylindrical chamber b, which are integrally assembled.

As shown in FIG. 1-2, the housing 21 of the large molded case is provided with a pole partition wall g, and the partition wall g is provided with a fixing plate 3 required for fixing the rolling bearing 19, and the fixing plate 3 can be fastened by screws. The detachable connection with the bearing housing f is convenient for installation and replacement, and the fixing plate 3 can adopt any suitable system of such a structure. In an optimised embodiment, the structure of the fixed rolling bearing 19 is constituted by upper and lower semi-circular bearing half holes respectively provided in the fixed plate 3 and the partition wall g; the lower semicircle is a semicircular groove formed by the partition g body As the bearing block f, the diameter thereof matches the outer diameter of the rolling bearing 19; the upper semicircle is composed of a fixing plate 3 having a bearing half hole as shown in FIG. 1 as a bearing cover plate, the diameter of which matches the outer diameter of the rolling bearing 19, The fixing plate 3 is fixed to the large molded case by screws. The outer ring of the rolling bearing 19 is fixed in the housing 21 by the mating connection of the bearing housing f to the fixing plate 3. With this mounting structure, the rolling bearing 19 shown in FIG. 9 for positioning and supporting is ensured to be loose and easy to install, and the extremely flexible rotating performance supported by each contact is obtained, while overcoming the prior art Solved by machining errors and installation A series of problems caused by errors affect the performance of the product, and it is economical to obtain high mounting positioning accuracy and sufficient load carrying capacity.

In summary, the existing circuit breaker design has a rotatable rod-shaped block or rotating shaft that fixedly connects the moving contact parts of the adjacent poles, and relies on it to support the opening and breaking of the moving contact bridge, to achieve different The consistency of the configuration of the breaking unit must ensure the precise cooperation between the rotating shaft and the large molded case of the circuit breaker. The key depends on the accuracy of the rod-shaped block or the rotating shaft and the metal shaped shaft acting in series with it, and the shaped metal shaft is difficult to process, and the dimensional accuracy is difficult. It is guaranteed that the insulation performance and strength of the rotating shaft will not be reduced, and the manufacturing and assembly errors of the rotating shaft supporting the opening and breaking of the movable contact bridge are difficult to meet the required supporting precision and assembly precision requirements of the designed components, and the between the pole units cannot be realized. Reliable mechanical connection and transmission. The invention improves the core component of the circuit breaker - contact support and synchronism and its arc extinguishing system, by cleverly connecting the direct plug connection between the plurality of contact supports, and skillfully in the directly coupled structure A rolling bearing is added, which is supported by two parallel-connected through-shafts 7 in series, so that the contact support with the bridge-shaped moving contact 20 of each pole is realized. The rotation axis of the 18 has an ideal coaxiality. Degree, rigidity and flexibility solve the defects that the dynamic contact bridges of the past poles are placed on the same rotating shaft through the contact support, which leads to the weakness of the circuit breaker, the temperature resistance and the insulation performance, which are easy to appear in the long-term operation of the circuit breaker. Technical indicators such as breaking performance and working stability of molded case circuit breakers. The invention does not need to provide a rotating shaft between the contact support of the adjacent poles, or it is not necessary to provide a connecting rod between the contact supports of the respective poles, but the double-contact bridge moving contact of each pole is supported by one contact 17 Or 18 supports, each contact supports a direct connection with the adjacent 18 contact support, reducing the connection point to improve the coaxiality, and a rolling bearing 19 is provided between two adjacent contact supports, the rolling bearing 19 is fixedly mounted on the partition g of the large molded case of the circuit breaker, and the center of rotation supported by each contact is defined by the center of rotation of the rolling bearing 19, so that the contacts support the axis of rotation of 17,18 and The axis of rotation of the rolling bearing 19 is coaxial. Since the rolling bearing 19 has extremely high rotation precision and sensitivity, the high sensitivity and high precision of the rotation of each contact support 18 are ensured, and the rolling bearing 19 only needs to be connected to the bearing connection end of the contact support 18, and since each pole One shaft is missing, so it is easier to ensure the accuracy of the slewing bearing and the stiffness against load deformation, which is beneficial to the synchronization between the contacts. The invention can ensure the accuracy requirement only by the precision of the mold itself, and reduces the influence of the unavoidable rigidity and strength deterioration factors due to the connection link, and is easy to debug.

The above description is only the preferred embodiment of the present invention, and all the technical equivalent changes and modifications made in the claims of the present invention should be considered as being within the scope of the present invention.

Claims

A multi-pole double-breakpoint molded case circuit breaker is provided with a plurality of chambers (22) formed by partition walls (g) for accommodating a plurality of single-pole breaking units (30) in an insulating casing, each single The pole breaking unit (30) has a unit molding shell, and each unit molding shell is provided with a contact system for performing the closing and breaking of the main circuit of the pole and a matching arc extinguishing system, and the contact system of each pole includes two relative configurations. Static contact (14, 16) and a bridge movable contact (20) capable of simultaneously closing and breaking with two fixed contacts (14, 16), each of the movable contacts (20) The elastic overtravel method is mounted on a contact support, and the operating mechanism (4) of the circuit breaker drives the contacts of the plurality of single-pole breaking units (30) to support synchronous rotation through the driving mechanism, and each arc extinguishing system includes two symmetry An arc extinguishing chamber (6, 9) disposed in the unit molded case, two static contacts (14, 16) are respectively disposed in the arc extinguishing regions of the two arc extinguishing chambers (6, 9), and are characterized Lie in:

The multi-pole double-breakpoint molded case circuit breaker further includes a plurality of rolling bearings (19), and an outer ring of the rolling bearing (19) is fixedly mounted on the partition wall (g) through a bearing mechanism, and the inside of the rolling bearing (19) The ring and the contact support are directly coupled in a static fit manner, and the adjacent two contact supports are directly plugged and connected in a static fit manner;

Between the two arc extinguishing chambers (6, 9) of the unit molded case of each single-pole breaking unit (30), a cylindrical chamber (b) supporting the contact is provided, and the cylindrical chamber is provided. (b) including a circular arc surface (a), between the cylindrical chamber (b) and the two arc extinguishing chambers (6, 9) are respectively provided with two arc walls (6a, 9a), in two compartments The arc walls (6a and 9a) are respectively provided with two through windows, and two ends of the bridge movable contact (20) respectively extend from the two windows into the two arc extinguishing chambers (6, 9);

The contact support includes an outer cylindrical surface (183) that cooperates with the circular arc surface (a) and between the outer cylindrical surface (183) and the circular arc surface (a) With a matching gap.
The multi-pole double-breakpoint molded case circuit breaker according to claim 1, wherein one end of the contact of one of the adjacent two single-pole breaking units (30) is supported along an axial direction X thereof. An integrally formed connecting shaft coaxial with the outer cylindrical surface (183) supported by the contact; the inner ring of the rolling bearing (19) is fitted on the connecting shaft in a static fit manner, and the other single pole breaking unit is One end of the contact support of (30) is provided with a connecting shaft hole (100) connected in a static fit with the connecting shaft along its axial direction X, and the setting and coupling of the connecting shaft and the connecting shaft hole (100) are satisfied. The condition that the outer cylindrical surface (183) supported by each contact is coaxial.
The multi-pole double-breakpoint molded case circuit breaker according to claim 1, wherein the circuit breaker comprises three single-pole breaking units (30) arranged side by side, and the single one of the three single-pole breaking units is located in the middle. Both ends of the contact end of the pole breaking unit (30) are provided with an integrally formed connecting shaft coaxial with the outer cylindrical surface (183) supported by the contact along the axial direction X thereof, and the inside of the two rolling bearings (19) The rings are respectively arranged on the connecting shafts at the two ends of the intermediate contact support in a static fit manner; at one end supported by the contacts of the other two single-pole breaking units (30), the connecting shaft is statically fitted along the axial direction X thereof. The connecting shaft hole (100) is connected in a manner, and the setting and coupling of the connecting shaft and the connecting shaft hole (100) satisfy the condition that the outer cylindrical surface (183) supported by each contact is coaxial.
A multi-pole double-breakpoint molded case circuit breaker according to claim 2 or 3, wherein: The connecting shaft comprises a rolling bearing connecting section (181) which is connected with the inner ring of the rolling bearing (19) in a static fit manner and a contact supporting connecting section (180) which cooperates with the connecting shaft hole (100), and the contact supporting connecting section ( The diameter of 180) is smaller than the diameter of the rolling bearing connecting section (181); the contact support is integrally formed by using a bulk molding compound or a sheet molding compound.
The multi-pole double-breakpoint molded case circuit breaker according to claim 4, wherein the contact supporting contact portion (180) supports a polygonal cross section, and the contact supports the connecting shaft hole (100). The cross section is a polygon that matches the cross section of the contact support connecting section (180).
The multi-pole double-breakpoint molded case circuit breaker according to claim 4, characterized in that: the contact support connecting portion (180) of the contact support (18) is provided with an inner ring of the rolling bearing (19) A mating shoulder (184) is provided, and the outer end surface of the connecting shaft hole (100) supported by the contact is provided with a mounting surface (185) in contact with the inner ring of the rolling bearing (19).
The multi-pole double-breakpoint molded case circuit breaker according to any one of claims 1 to 3, characterized in that: the driving mechanism comprises two through shafts (7) arranged in parallel with each other, and each of the contact supports is respectively Two small through holes (18a) are arranged along the axial direction X thereof, and the two through shafts (7) respectively pass through the two small through holes (18a) of the respective contact supports and are coupled with the contacts of the operating mechanism (4) The pieces are fixedly coupled, and the axis of rotation of the contact coupler is coaxial with the axis of the outer cylindrical surface (183) supported by each contact.
The multi-pole double-breakpoint molded case circuit breaker according to any one of claims 1 to 3, characterized in that the driving mechanism comprises two convex shafts disposed on the contact coupling members of the operating mechanism (4), Two small through holes (18a) are disposed on the contact supports of the contact couplings of the respective operating mechanisms (4), and the two protruding shafts are respectively plugged and coupled with the two small through holes (18a), The axis of rotation of the contact coupling is coaxial with the axis of the outer cylindrical surface (183) supported by the contact.
The multi-pole double-breakpoint molded case circuit breaker according to any one of claims 1 to 3, characterized in that: said bearing mechanism comprises a fixing plate (3) having a bearing half hole, and is disposed on the partition wall (g) The bearing seat (f) with the bearing half hole, the fixing plate (3) is fixedly coupled with the bearing seat (f) and the two bearing half holes are butted, and the outer ring of the rolling bearing (19) is statically matched with the two butts The bearing is half-hole connected for installation.
The multi-pole double-breakpoint molded case circuit breaker according to claim 1, wherein the unit molded case of each single-pole breaking unit (30) comprises a first small side shell plate (10) and a second small side, respectively. The shell plate (11), the third small side shell plate (12), the fourth small side shell plate (13), the first small side shell plate (10) and the second small side shell plate (11) are assembled to form a first The arc extinguishing chamber (6) and the first semi-cylindrical chamber, the third small side shell plate (12) and the fourth small side shell plate (13) are oppositely assembled to form a second arc extinguishing chamber (9) and a second semi-cylindrical cylinder a first chamber (c1) and a second engaging portion (c2) are disposed on the first arc extinguishing chamber (6), and a third engaging portion is disposed on the second arc extinguishing chamber (9) ( D1) and the fourth engaging portion (d2), the first engaging portion (c1) and the third engaging portion (d1) are snap-fitted to form a fixed coupling, and the second engaging portion (c2) and the fourth engaging portion (d2) the snap fit forms a fixed coupling, and the first semi-cylindrical chamber and the second semi-cylindrical chamber are assembled into a cylindrical shape by a fixed connection of the first arc extinguishing chamber (6) and the second arc extinguishing chamber (9) Chamber (b).
The multi-pole double-breakpoint molded case circuit breaker according to claim 1, wherein the unit molded case of each single-pole breaking unit (30) comprises a first large side shell plate (23) and a second large side shell. The plate (24), the first large side shell plate (23) is assembled opposite the second large side shell plate (24) to form two arc extinguishing chambers (6, 9) and a cylindrical chamber (b).