Vacuum circuit breaker and transmission mechanism thereof

Abstract

The utility model relates to a vacuum circuit breaker and a transmission mechanism thereof. The vacuum circuit breaker comprises an operating mechanism and a contact unit which is controlled by the operating mechanism to open and close. The transmission mechanism is adapted to be connected between the operating mechanism and the contact unit. The transmission mechanism comprises a first main shaft which can rotate around the central axis of the first main shaft and is suitable for being operably connected to the operation mechanism; the second main shaft and the first main shaft are arranged in parallel and at an interval; the first transmission part is connected between the first main shaft and the second main shaft, and the first transmission part is constructed to be located at a dead point position when the contact unit is in a closed state and can be driven by the operating mechanism to cross the dead point position so as to allow the contact unit to be opened; and the second transmission part is connected between the second main shaft and the contact unit, and is separated from the first transmission part along the axial direction of the second main shaft.

Description

TECHNICAL FIELD

[0001] The utility model relates to vacuum switch equipment technical field especially relates to vacuum circuit breaker and transmission mechanism thereof. BACKGROUND

[0002] As the core switch equipment of medium and high voltage power system, the closing stability of vacuum circuit breaker directly affects the safety of power grid. The traditional transmission mechanism of vacuum circuit breaker adopts single main shaft driving link structure. When closing, the operating mechanism (such as spring mechanism) drives the crank arm and pull rod through the main shaft to push the moving contact to close. However, the repulsive force of contact will be caused by the electric force (such as Holm force, Lorentz force) generated by current passing through at the moment of contact closing, which will cause the reverse movement of moving contact. If the reverse thrust is transmitted back to the operating mechanism through the transmission chain, it will cause the wear and even failure of mechanism components, reducing the service life of the equipment.

[0003] In the prior art, mechanical locking or hydraulic buffer device is usually used to inhibit the transmission of reverse thrust, but such scheme has defects such as complex structure, response lag or high maintenance cost. For example, a known vacuum circuit breaker anti-rebound mechanism realizes locking through additional spring and clamping groove, but it needs additional space layout and is easy to fail due to spring fatigue. A known hydraulic contact repulsion force buffer device can absorb the recoil energy, but it increases the sealing requirement and failure risk.

[0004] Therefore, there is an urgent need for a vacuum switch equipment with compact structure, which can actively block the transmission of reverse thrust and increase the closing stability. SUMMARY

[0005] The utility model aims at providing a transmission mechanism of vacuum circuit breaker, which can at least solve part of the above technical problems.

[0006] The utility model also aims at providing a vacuum circuit breaker applying the improved transmission mechanism.

[0007] According to one aspect of the utility model, a transmission mechanism of vacuum circuit breaker is provided, the vacuum circuit breaker comprises an operating mechanism and a contact unit controlled by the operating mechanism to close and open, the transmission mechanism is adapted to be connected between the operating mechanism and the contact unit, and the transmission mechanism comprises: a first main shaft rotatable around its central axis and operably connected to the operating mechanism; a second main shaft arranged in parallel with and spaced from the first main shaft; a first transmission part connected between the first main shaft and the second main shaft, wherein the first transmission part is configured to be at a dead point position when the contact unit is in the closing state, and can pass the dead point position under the driving of the operating mechanism to allow the contact unit to open; and a second transmission part connected between the second main shaft and the contact unit and spaced from the first transmission part in the axial direction of the second main shaft.

[0008] The transmission mechanism is used for connecting between an operating mechanism of a vacuum circuit breaker and a vacuum contact unit, and transmitting the action of the operating mechanism to a movable contact of the vacuum contact unit to control the opening and closing of the vacuum switch unit. The transmission mechanism forms a self-locking mechanism by designing the transmission part between the two main shafts to be at a dead point position during the closing of the movable contact and the static contact, ensuring that the insulation pull rod of the movable contact remains stuck before the opening action. Thus, the electrodynamic repulsive force generated between the movable contact and the static contact due to the closing will not be transmitted back to the operating mechanism, while meeting the transmission requirements and improving the safety of the operating mechanism. The transmission mechanism of the present scheme has high reliability and does not require additional buffer elements. The pure mechanical structure has strong fatigue resistance and reduces the maintenance frequency of the equipment during the service life.

[0009] In some embodiments, the contact unit has a plurality of units, the second main shaft is a single main shaft crossing the entire vacuum circuit breaker, and a plurality of second transmission parts are arranged along the axial direction of the single main shaft and connected between the single main shaft and the plurality of contact units, thereby sharing the single main shaft.

[0010] In some embodiments, the first transmission part comprises: a toggle arm connected to the first main shaft in a follow-up manner and having an arm segment extending transversely to the first main shaft; and a transmission rod hingedly connected to the toggle arm at one end and drivingly connected to the second main shaft at the other end; wherein when the toggle arm is rotated to the arm segment being collinear with the transmission rod under the driving of the first main shaft, the first transmission part is at the dead point position.

[0011] In some embodiments, the transmission rod comprises a pair of rod portions oppositely arranged on opposite sides of the toggle arm, each rod portion being hingedly connected to the toggle arm at one end and having a hook segment formed at the other end, and the hook segments of the pair of rod portions being opposite to each other to form an aperture through which the second main shaft passes.

[0012] In some embodiments, the second transmission part is modular, comprising a pair of side plates oppositely arranged and a transmission assembly arranged between the pair of side plates, the transmission assembly being connected between the second main shaft and the contact unit, and one of the pair of side plates being detachably connected to the housing of the contact unit.

[0013] In some embodiments, the contact unit includes an insulating pull rod connected to the movable contact, and the transmission assembly includes a slider connected to the second spindle in a following manner and hinged to at least one of the pair of side plates, the slider being formed with a long hole at a position spaced from the spindle and the hinge point; a first connecting rod having one end drivingly connected to the insulating pull rod and the other end hinged to the long hole of the slider and slidable along the long hole; and a second connecting rod having one end hinged to the end of the first connecting rod away from the contact unit and the other end hinged to at least one of the pair of side plates between the two ends of the first connecting rod.

[0014] In some embodiments, the first connecting rod is formed with a recess between the two ends, and the end of the second connecting rod hinged to the side plate is capable of abutting against the recess.

[0015] In some embodiments, the second transmission part includes a support abutting against the pair of side plates, the support defining a gap width between the pair of side plates for accommodating the transmission assembly, and the support and the pair of side plates being connected to the housing of the contact unit by a common shaft.

[0016] According to another aspect of the present application, there is provided a vacuum circuit breaker including an operating mechanism and at least one contact unit controlled by the operating mechanism to open and close, and further including a transmission mechanism connected between the operating mechanism and the at least one contact unit, the transmission mechanism being the aforementioned transmission mechanism.

[0017] In some embodiments, the contact unit is modular, including a housing and a vacuum interrupter accommodated in the housing, a movable contact of the vacuum interrupter being operatively connected to the second transmission part of the transmission mechanism.

[0018] Some of the other features and advantages of the present application will become apparent from the specification, and will be subject to interpretation as being within the purview of persons skilled in the art, upon study of the specification. BRIEF DESCRIPTION OF DRAWINGS

[0019] Hereinafter, embodiments of the present application will be described in detail with reference to the accompanying drawings.

[0020] Figure 1 is a schematic view of a vacuum circuit breaker according to an embodiment of the present application;

[0021] Figure 2 is a schematic view of a three-phase conducting loop in a vacuum circuit breaker according to an embodiment of the present application;

[0022] Figure 3 is a schematic view of a contact unit according to an embodiment of the present application;

[0023] Figure 4 is a schematic view of a contact unit without a housing according to an embodiment of the present utility model;

[0024] Figure 5 is a schematic view of a first spindle and a first transmission part according to an embodiment of the present utility model;

[0025] Figure 6 is a schematic view of a second transmission part according to an embodiment of the present utility model;

[0026] Figure 7 is an exploded schematic view of a second transmission part according to an embodiment of the present utility model;

[0027] Figure 8 is a schematic view of a contact unit and a transmission mechanism according to an embodiment of the present utility model, wherein the contact unit is in an open state;

[0028] Figure 9 is a schematic view of a contact unit and a transmission mechanism according to an embodiment of the present utility model, wherein the contact unit is in a closed state.

[0029] BRIEF DESCRIPTION OF DRAWINGS

[0030] 1 - vacuum circuit breaker; 2 - operating mechanism; 3 - first spindle; 4 - second spindle; 5 - contact unit; 50 - housing; 500 - first housing part; 502 - second housing part; 504 - long hole; 506 - hole; 51 - vacuum interrupter; 52 - insulating pull rod; 53 - crossbar; 54 - first connecting terminal; 55 - flexible connection; 56 - second connecting terminal; 6 - first transmission part; 60 - crank; 62 - transmission rod; 620 - rod part; 622 - hook section; 624 - aperture; 64 - pin shaft; 66 - pin shaft; 7 - second transmission part; 70 - side plate; 700 - long hole; 702 - hole; 704 - hole; 706 - hole; 708 - notch; 72 - sliding piece; 720 - sliding tab; 722 - long hole; 724 - hole; 726 - hole; 74 - first connecting rod; 740 - recess; 742 - hole; 744 - hole; 746 - hole; 76 - second connecting rod; 760 - rod part; 762 - pin shaft; 764 - pin shaft; 78 - support; 780 - shaft DETAILED DESCRIPTION

[0031] The schematic solutions of the technical solutions disclosed in this utility model are now described in detail with reference to the accompanying drawings. Although the drawings are provided to illustrate some embodiments of this utility model, the drawings are not necessarily drawn to the dimensions of the specific embodiments, and certain features may be enlarged, removed, or partially cut to better illustrate and explain the disclosure of this utility model. Some components in the drawings may be repositioned according to actual needs without affecting the technical effect. The phrase "in the drawings" or similar terms appearing in the specification do not necessarily refer to all drawings or examples.

[0032] Certain directional terms used in the description of the accompanying drawings below, such as “inner,” “outer,” “above,” “below,” and other directional terms, will be understood to have their normal meaning and refer to those directions as normally viewed in the accompanying drawings. Unless otherwise specified, the directional terms used in this specification are generally in accordance with the conventional directions understood by those skilled in the art.

[0033] The terms “first,” “first,” “second,” “second,” and similar terms used in this utility model do not indicate any order, quantity, or importance, but are used to distinguish one component from other components.

[0034] Vacuum circuit breakers are a type of switching equipment widely used in power systems. They mainly control the opening and closing of circuits by opening and closing moving contacts and stationary contacts. Figure 1 An exemplary vacuum circuit breaker 1 is shown, mainly comprising an operating mechanism 2, a transmission mechanism, and contact units 5. Multiple contact units 5 are each connected to the operating mechanism 2 via the transmission mechanism, and can uniformly perform opening or closing actions under the control of the operating mechanism 2. The operating mechanism 2 can be selected from various existing structures, such as a spring-energy-storage operating mechanism, which mainly includes an energy-storage spring, a motor, a manual energy storage device, and a tripping device. The energy-storage spring stores mechanical energy and provides the power required for opening and closing. The motor and the manual energy storage device compress the energy-storage spring to achieve an energy-storage state. The tripping device actuates upon receiving an opening signal to release the energy of the energy-storage spring.

[0035] like Figure 2 As shown in more detail, multiple contact units 5 (three are shown in the figure) are connected in parallel to the operating mechanism 2. Each contact unit 5 is modular and can be replaced as a whole, improving the efficiency of maintenance operations. Figure 3 and Figure 4The detailed structure of the single contact unit 5 is shown. As shown, the contact unit 5 comprises a housing 50 and a vacuum interrupter 51 accommodated in the housing 50. The housing 50 is hollow and open at both upper and lower ends. Such a housing 50 can be integrally formed or in a split structure. In the shown embodiment, the housing 50 comprises a first housing part 500 and a second housing part 502 which are detachably connected together in any suitable manner such as snap connection or bolt connection.

[0036] The vacuum interrupter 51 comprises a solid casing and a moving contact and a stationary contact sealed in the casing. An insulating pull rod 52 extends into the casing and is connected to the moving contact at one end and extends out of the casing and is connected to the operating mechanism 2 through a transmission mechanism at the other end. Under the control of the operating mechanism 2, the insulating pull rod 52 can move along the axis and push the moving contact to approach and engage with the stationary contact to realize the closing of the vacuum circuit breaker, and can also pull the moving contact to separate from the stationary contact to realize the opening of the vacuum circuit breaker. In order to connect the transmission mechanism, the insulating pull rod 52 is connected with a cross bar 53 arranged radially at the top end. The cross bar 53 passes through a long hole 504 on the housing 50 of the contact unit 5 and can move along the long hole 504 under the drive of the transmission mechanism to drive the axial movement of the insulating pull rod 52. The insulating pull rod 52 is connected to a first connecting terminal 54 through a flexible connection 55 at the bottom end, and the first connecting terminal 54 is mounted to the housing 50. The stationary contact of the vacuum interrupter 51 is connected to a second connecting terminal 56 located outside the casing, and the second connecting terminal 56 is also mounted to the housing 50. Through the first connecting terminal 54 and the second connecting terminal 56, the vacuum circuit breaker 1 can be connected to a circuit.

[0037] The detailed structure of the transmission mechanism is shown in Figures 5 to 7 As shown, the transmission mechanism of the utility model has a blocking function during the closing of the vacuum circuit breaker 1 to keep the insulating pull rod of the moving contact blocked before the moving contact and the stationary contact are separated, preventing the reverse thrust between the contacts from being transmitted to the operating mechanism 2.

[0038] In the illustrated embodiment, the first main shaft 3 and the second main shaft 4 are arranged parallel and spaced apart. Each of the first and second main shafts 3 and 4 extends laterally through the vacuum circuit breaker 1 as a single shaft, with each shaft supported at both ends by bearings. The first main shaft 3 is connected to the operating mechanism 2 and receives its rotational driving force. For the entire vacuum circuit breaker 1, a single first main shaft 3 and a single second main shaft 4 are provided for all contact units 5. This allows for the installation of support frames only at the two ends of the first main shaft 3. Connecting multiple contact units 5 in parallel to the same first main shaft 3 and second main shaft 4 also helps improve the uniformity of their operation. After prolonged operation of the power equipment, wear inevitably leads to misalignment between the operating mechanism 2, the transmission mechanism, and the moving parts of the contact units 5. Connecting multiple contact units 5 to a common first main shaft 3 and second main shaft 4 effectively avoids inconsistent opening and closing actions of the contact units 5 due to uneven misalignment, thus improving the stability and reliability of the vacuum circuit breaker 1.

[0039] The first main shaft 3 is connected to the operating mechanism 2 and can rotate around its own central axis in response to the action of the operating mechanism 2 to drive the moving contacts of each contact unit 5 to move. In order to balance the force on each contact unit 5, multiple transmission mechanisms can be arranged at intervals along the axial direction of the first main shaft 3. These transmission mechanisms are also arranged at intervals along the axial direction of the second main shaft 4. In the illustrated embodiment, the transmission mechanism includes a first transmission part 6 connected between the first main shaft 3 and the second main shaft 4, and a second transmission part 7 connected between the second main shaft 4 and the insulating pull rod 52 of the vacuum interrupter 51.

[0040] The first transmission part 6 connects the first spindle 3 and the second spindle 4, transmitting the force applied to the first spindle 3 by the operating mechanism 2 to the second spindle 4. Figure 5 As shown, the second transmission part 6 includes a crank arm 60 and a transmission rod 62 hinged together. The crank arm 60 forms a through hole through which the first main shaft 4 passes and is connected to the crank arm 60 in a non-moving manner, so that the rotation of the first main shaft 3 around its own central axis can drive the crank arm 60 to rotate synchronously. One arm segment of the crank arm 60 extends from the rotation center of the crank arm 60 in a direction away from the first main shaft 4. The transmission rod 62 is hinged to this extended arm segment of the crank arm 60 by a pin 66. When the crank arm 60 rotates around the central axis of the first main shaft 3 until its arm segment is collinear with the transmission rod 62, the transmission mechanism is in a dead position and self-locking. At this time, the contact repulsion force generated between the moving contact and the stationary contact due to closing forms an internal force closed loop with the second transmission part 7 through the crossbar 53, which locks the insulating pull rod 52 of the contact unit 5. The closing repulsion force generated on one side of the contact unit 5 cannot return to the operating mechanism 2 through the transmission chain, thereby blocking the reverse thrust.

[0041] The transmission rod 62 can have any suitable structure, such as a one-piece rod or a split assembly. In the illustrated embodiment, the transmission rod 62 comprises two rod portions 620 arranged on opposite sides of the toggle arm 60 and connected by a pin 64 to sandwich the toggle arm 60. A pin 66 passes through the two rod portions 620 and the toggle arm 60 to form the hinge of the transmission rod 62 to the toggle arm 60. Each rod portion 620 forms a hook section 622 at an end distal to the toggle arm 60, and the hook sections 622 of the two rod portions 620 are opposite to each other to enclose an aperture 624 between the two hook sections 622 for the second shaft 4 to pass through. The two hook sections 622 also form a clamp to the second shaft 4 to prevent relative movement between the transmission rod 62 and the second shaft 4. The opposite rod portions 620 of the two hook sections 622 facilitate direct mounting of the transmission rod 62 to the entire second shaft 4 at the desired position, even if the second shaft 4 has already been mounted to the vacuum circuit breaker 1. A conventional one-piece transmission rod 62 needs to be sleeved onto the second shaft 4 from an end of the second shaft 4 and moved to the desired position, which is particularly inconvenient for assembly or maintenance of the vacuum circuit breaker 1.

[0042] The number of the first transmission portions 6 can correspond to the number of the contact units 5, and each first transmission portion 6 is substantially aligned with the central connection of the housing 50 of a corresponding one of the contact units 5 between the first shaft 3 and the second shaft 4.

[0043] The second transmission portion 7 is connected between the second shaft 4 and the insulating link 52 of the vacuum interrupter 51, and is axially spaced apart from the first transmission portion 6 along the second shaft 4. Figure 6 and Figure 7 As shown, the second transmission portion 7 can be modular, comprising two opposite side plates 70 and a transmission assembly housed between the two side plates 70. The second transmission portion 7 can be connected as a whole to the side of the housing 50 of the contact unit 5, such as clamped between two adjacent contact units 5, or connected to the side of the outermost contact unit 5 facing away from other contact units 5, and connected to the end of the crossbar 53 of the contact unit 5 extending out of the elongated hole 504 of the housing 50. Adaptively, each of the two side plates 70 has an elongated hole 700 aligned with the elongated hole 504 of the housing 5 for the crossbar 53 to slide along. The second transmission portion 7 comprises a sliding member 72, a first link 74 and a second link 76.

[0044] The sliding link 72 has spaced apart holes 724 and 726. The hole 724 is for the second spindle 4 to pass through, thereby connecting the sliding link 72 and the second spindle 4 together in a non- relative motion manner. The hole 726 is hingedly connected to the two side plates 70 by a pin shaft, or is hingedly connected to one of the two side plates 70, and can rotate about the central axis of the pin shaft. To this end, the side plate 70 can be formed with a hole 706 aligned with the hole 726 for the pin shaft to pass through. The sliding link 72 is formed with a long hole 722 at a position triangularly arranged with the hole 724 and the hole 726, and the first connecting rod 74 is provided with a pivot at the first end, which passes through the long hole 722 and can slide along the long hole 722, so that the first connecting rod 74 is movably hingedly connected to the sliding link 72. The sliding link 72 can be an integral piece, or can be an assembled piece. In the embodiment shown, the sliding link 72 includes a pair of sliding link pieces 720, which are arranged on opposite sides of the first connecting rod 74 and are connected together by the pin shaft passing through the hole 726 and the hole 706.

[0045] The sliding link 72 can drive the first connecting rod 74 to move synchronously under the drive of the second spindle 4. The first end of the first connecting rod 74 is hingedly connected to the long hole 722 of the sliding link 72 by a pin shaft passing through the hole 744, and the second end of the first connecting rod 74 opposite to the first end is formed with a hole 742 for the first connecting rod 74 to be sleeved on the cross bar 53 of the vacuum interrupter 51, so that the first connecting rod 74 can rotate about the central axis of the cross bar 53. Another hole 746 is formed at a position of the first connecting rod 74 close to the first end and spaced apart from the hole 744, and the first end of the second connecting rod 76 is hingedly connected to the first connecting rod 74 by a pin shaft 764 passing through the hole 746. The second end of the second connecting rod 76 is hingedly connected to the two side plates 70 by a pin shaft 762, or is hingedly connected to one of the two side plates 70. The side plate 70 can be formed with a hole 704 for the pin shaft 762 to pass through. At this point, the second connecting rod 76 is hingedly connected between the first connecting rod 74 and the side plate 70. The second connecting rod 76 can be an integral piece, or can be an assembled piece. In the embodiment shown, the second connecting rod 76 includes a pair of rod portions 760, which are arranged on opposite sides of the first connecting rod 74 and are connected together by the pin shaft 762 and the pin shaft 764.

[0046] A recess 740 is formed between the first end and the second end of the first connecting rod 74, and the second end of the second connecting rod 76, or the pin shaft 762, can be in or away from the recess 740 during movement.

[0047] The two side plates 70 form a receiving space for the transmission assembly with the gap between them. To ensure the stability of the second transmission part 7, a support member 78 or a support block is sandwiched between the two side plates 70. The width of the support member 78 defines the size of the gap between the two side plates 70. The support member 78 can be arranged at any suitable position between the two side plates 70 and is positioned by rods connected to the side plates 70. In the illustrated embodiment, the two support members 78 are arranged at the upper and lower ends of the side plates 70. The side plates 70 have two holes 702 formed for mounting the support members 78, and two shafts 780 can pass through the two holes 702 and corresponding holes on the two support members 78 respectively to fix the support members 78 between the two side plates 70. The shafts 780 can also pass through the housing 50 as mounting rods to connect the second transmission part 7 to the housing 50 of the contact unit 5, for which the housing 50 has two corresponding holes 506. In one embodiment, all second transmission parts 7 share an upper shaft that runs through all contact units 5, and also share a lower shaft that runs through all contact units 5.

[0048] In order to reduce the overall thickness of the second transmission part 7, a relief notch 708 can be formed in the side plate 70 at the position where the sliding member 72, the first connecting rod 74 and the second connecting rod 76 are hinged, so as to allow the pin connecting the sliding member 72 and the first connecting rod 74, and the pin connecting the first connecting rod 74 and the second connecting rod 76 to move within the notch 708, so as to avoid interference with the side plate 70.

[0049] The closing process of vacuum circuit breaker 1 is as follows:

[0050] like Figure 8 As shown, in the open state, the operating mechanism 2 drives the first main shaft 3 to rotate counterclockwise as shown in the figure, driving the crank arm 60 to rotate synchronously. The movement of the crank arm 60 drives the transmission rod 62 to move, and further drives the second main shaft 3 to lift. The movement of the second main shaft 3 drives the sliding joint 72 to rotate clockwise around the pin connecting it to the side plate 70 as shown in the figure, pulling the first connecting rod 74, and further pulling down the crossbar 53 to drive the moving contact connected to the insulating pull rod 52 to approach the stationary contact. When it reaches... Figure 9 When the circuit is closed as shown, the arm of the crank arm 60 is collinear with the transmission rod 62 (e.g., Figure 9 (As shown in the dead position), at this time the transmission mechanism is in a self-locking state, and the contact repulsion force cannot be transmitted in the reverse direction to the first main shaft 3 through the crossbar 53. In addition, the pin 762 at the first end of the second connecting rod 76 abuts against the first connecting rod 74 in the recess 740.

[0051] The opening process of vacuum circuit breaker 1 is as follows:

[0052] like Figure 9As shown, in the closing state, the operating mechanism 2 reversely drives the first spindle 3, and the arm segment of the toggle arm 60 is separated from the collinear state with the transmission rod 62, so that the toggle arm 60 passes through the dead point position. The second spindle 4 is lowered along with the movement of the transmission rod 62, which promotes the rotation of the sliding piece 72 and pushes up the first connecting rod 74, at this time the second connecting rod 76 rotates to the first end away from the recess 740 of the first connecting rod 74. In this way, the moving contact of the vacuum interrupter 61 is lifted by the insulating pull rod 52, and the opening is completed.

[0053] The whole first spindle 3 and the second spindle 4 ensure that when the operating mechanism 2 acts, the moving contacts of all the head units 5 act synchronously, and the synchronization of the multi-break closing is realized. In addition, the contact repulsion of each break is independently blocked by the corresponding dead point structure, and does not interfere with each other. The vacuum circuit breaker 1 of the utility model has compact layout, and can greatly reduce the manufacturing and debugging cost.

[0054] It should be understood that although the present specification is described according to each embodiment, not every embodiment contains only one independent technical solution, and the description manner of the specification is only for the sake of clarity, and the skilled person in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be combined to form other embodiments which can be understood by the skilled person.

[0055] The above description is only a specific embodiment of the utility model, and is not used to limit the scope of the utility model. Any equivalent changes, modifications and combinations made by those skilled in the art without departing from the concept and principles of the utility model shall belong to the protection scope of the utility model.

Claims

1. A transmission mechanism of a vacuum circuit breaker including an operating mechanism and a contact unit whose opening and closing are controlled by the operating mechanism, the transmission mechanism being adapted to be connected between the operating mechanism and the contact unit, characterized in that, The transmission mechanism comprises: a first spindle rotatable about a central axis thereof and adapted to be operatively connected to the operating mechanism; a second spindle arranged in parallel with and spaced from the first spindle; a first transmission portion connected between the first spindle and the second spindle, wherein the first transmission portion is configured to be at a dead point position when the contact unit is in a closed state and is drivable beyond the dead point position under the drive of the operating mechanism to allow the contact unit to be opened; a second transmission portion connected between the second spindle and the contact unit and spaced from the first transmission portion in an axial direction of the second spindle.

2. The drive mechanism of the vacuum circuit breaker according to claim 1, characterized in that, The contact unit is provided in plurality, and the second spindle is a single spindle extending across the entire vacuum circuit breaker, and the plurality of second transmission portions are arranged in the axial direction of the single spindle and connected between the single spindle and the plurality of contact units, thereby sharing the single spindle.

3. The drive mechanism of a vacuum circuit breaker according to claim 1 or 2, characterized in that, The first transmission portion comprises: a bell crank operatively connected to the first spindle and having an arm segment extending transversely to the first spindle; a transmission rod hingedly connected at one end to the bell crank and drivingly connected at the other end to the second spindle; wherein the first transmission portion is at the dead point position when the bell crank is rotated to a position in which the arm segment is collinear with the transmission rod under the drive of the first spindle.

4. The drive mechanism of the vacuum circuit breaker according to claim 3, characterized in that, The transmission rod comprises a pair of rod portions arranged opposite to each other on opposite sides of the bell crank, each rod portion being hingedly connected at one end to the bell crank and having a hook segment formed at the other end, the hook segments of the pair of rod portions being opposite to each other to form an aperture through which the second spindle passes.

5. The drive mechanism of the vacuum circuit breaker according to claim 1 or 2, characterized by, The second transmission portion is modular, comprising a pair of side plates arranged opposite to each other and a transmission assembly arranged between the pair of side plates, the transmission assembly being connected between the second spindle and the contact unit, one of the pair of side plates being detachably connected to a housing of the contact unit.

6. The drive mechanism of the vacuum circuit breaker according to claim 5, characterized in that, The contact unit comprises an insulating pull rod connected to a movable contact, and the transmission assembly comprises: a sliding member operatively connected to the second spindle and hingedly connected to at least one of the pair of side plates, the sliding member being formed with an elongated hole at a position spaced from the spindle and the hinged connection point; a first link drivingly connected at one end to the insulating pull rod and hingedly connected at the other end to the elongated hole of the sliding member and slidable along the elongated hole; a second link hingedly connected at one end to the end of the first link away from the contact unit and hingedly connected at the other end to at least one of the pair of side plates between the two ends of the first link.

7. The drive mechanism of the vacuum circuit breaker according to claim 6, characterized in that, The first link is formed with a recess between the two ends, and the end of the second link hingedly connected to the side plate is abuttable to the recess.

8. The drive mechanism of the vacuum circuit breaker according to claim 5, characterized in that, The second transmission portion comprises a support abutting between the pair of side plates, the support defining a gap width between the pair of side plates for accommodating the transmission assembly, and the support and the pair of side plates are connected to the housing of the contact unit by a common shaft.

9. A vacuum circuit breaker comprising an operating mechanism and at least one contact unit controlled by the operating mechanism to open and close, further comprising a transmission mechanism connected between the operating mechanism and the at least one contact unit, characterized in that, The transmission mechanism is any one of the transmission mechanisms according to claims 1 to 8.

10. The vacuum circuit breaker of claim 9, wherein, The contact unit is modular, comprising a housing and a vacuum interrupter housed within the housing, a movable contact of the vacuum interrupter being operatively connected to the second drive portion of the drive mechanism.

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