Vacuum circuit breaker and method for tensioning opening spring of vacuum circuit breaker

Abstract

A vacuum circuit breaker includes a vacuum circuit breaker unit (500) and a drive unit (100). The driving unit (100) comprises an opening spring (110) for biasing a movable contact (510) of the vacuum circuit breaker unit (500) to an open position; and a spring tension adjusting mechanism. The spring tension adjustment mechanism includes an adjustment actuator (120) and a rigid coupling rod (130) connecting the adjustment actuator (120) to the second end of the opening spring (110). The adjustment actuator (120) is arranged offset from the opening spring axis (170).

Description

Technical Field

[0001] Some aspects of the present disclosure relate to circuit breakers, in particular vacuum circuit breakers, and more particularly to vacuum circuit breakers having an opening spring. Some aspects of the present disclosure also relate to a method for tensioning an opening spring of such a circuit breaker. Background Art

[0002] A circuit breaker is a switching device that performs a protective function in an associated circuit. A circuit breaker can be actuated between a closed configuration (a closed position of the movable contacts), in which the circuit breaker allows current to flow between two parts of an associated circuit, and an open configuration (an open position of the movable contacts), in which the circuit breaker interrupts this current flow. In contrast to other types of circuit breakers, circuit breakers are suitable for interrupting fault currents, such as overload currents or short-circuit currents.

[0003] A circuit breaker comprises at least one circuit breaker unit, which generally comprises a movable contact / moving contact and a fixed contact / stationary contact. Actuation of the circuit breaker generally comprises a mechanism for moving the movable contact between a closed position, in which the movable contact and the fixed contact are in contact, and an open position, in which the movable contact and the fixed contact are separated from each other.

[0004] In vacuum circuit breakers, the arc extinguishing medium and the insulating medium of the contact gap after arc extinguishing are vacuum. The arc extinguishing medium and the insulating medium of the contact gap (i.e. vacuum) are usually arranged in a vacuum housing (so-called vacuum bottle) of one or more circuit breaker units. Vacuum circuit breakers are often used in power distribution networks.

[0005] The energy source and kinematic chain required to move the movable contact are provided under clear size restrictions to transmit energy. In addition, the energy source and kinematic chain are subject to strict restrictions in manufacturing and assembly tolerances so that the force and movement of the movable contact meet the specifications.

[0006] When the circuit breaker is in the open position, it is important to keep the circuit breaker stably in the open position. However, in a vacuum circuit breaker, the negative pressure in the vacuum chamber usually generates a force that pulls the movable contact toward the closed position. In order to counteract this force, a trip spring can be provided to bias the movable contact toward the open position.

[0007] However, there is a problem in that the opening spring must meet strict requirements in terms of tolerances so that the forces and movements of the movable contacts continue to meet specifications.

[0008] In view of the above, there is a need in the art for an energy-saving, compact and adjustable circuit breaker. Summary of the invention

[0009] In view of the current needs, the object of the present invention is to provide a vacuum circuit breaker, in particular a vacuum circuit breaker with a drive unit having a trip spring, which can operate reliably in various environments without excessive requirements on the components provided and the required space. In particular, it is desired to achieve reliable operation without excessive requirements on the trip spring.

[0010] To provide a brief summary of the invention, aspects of the invention are described below.

[0011] According to one aspect, a vacuum circuit breaker includes a vacuum circuit breaker unit and a drive unit. The drive unit includes: a trip spring for biasing a movable contact of the vacuum circuit breaker unit toward an open position; and a spring tension adjustment mechanism. The spring tension adjustment mechanism includes: an adjustment actuator; and a rigid coupling rod connecting the adjustment actuator to a second end of the trip spring. The adjustment actuator is arranged to deviate from the trip spring axis.

[0012] More specifically, the vacuum circuit breaker unit has a movable contact configured to switch between an open position and a closed position. A drive unit is coupled to the movable contact for actuating movement between the closed position and the open position; the drive unit includes an opening spring operably connected to the movable contact at a first end for biasing the movable contact toward the open position. The adjustment actuator is configured to position the second end of the opening spring at a plurality of positions corresponding to a plurality of lengths of the opening spring.

[0013] According to one aspect, a trip spring is described. The trip spring may be a tension spring. A tension spring is different from other types of springs (such as compression springs or torsion springs). For example, a tension spring may be configured to receive a tensile load, for example during actuation of the spring, and to generate a spring force in response to the tensile load. In a vacuum circuit breaker according to an embodiment, the length of the trip spring at which the tensile load causes the trip spring to deviate from a neutral / relaxed position may be substantially proportional to the spring force of the trip spring. According to some embodiments, the tension spring may include one or more hooks, which are particularly used to engage an open hook and / or a rod with a spring connection structure.

[0014] Advantageously, a cost-effective and compact circuit breaker is provided.

[0015] Other aspects, embodiments and examples and their benefits may be further understood through the detailed description with reference to the accompanying drawings, which are briefly described as follows. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The various aspects, embodiments and examples of the invention and their advantages will emerge more clearly from the detailed description, which is described in an illustrative and non-limiting manner with the aid of the accompanying drawings, in which:

[0017] Figure 1 A circuit breaker having a drive unit with a spring tension adjustment mechanism according to aspects and embodiments described herein is shown;

[0018] Figure 2 A drive unit according to the embodiments and examples described herein is shown, which has a spring tension adjustment mechanism and a trip spring in a free length state;

[0019] Figure 3 A drive unit according to the embodiments and examples described herein is shown, which has a spring tension adjustment mechanism and a brake opening spring in a pre-tensioned state;

[0020] Figure 4 A drive unit according to the embodiments and examples described herein is shown, which has a spring tension adjustment mechanism and a trip spring in a tensioned position;

[0021] Figure 5 A drive unit according to the embodiments and examples described herein is shown, which has a slotted hole and a spring positioning slot;

[0022] Figure 6 A method of tensioning a trip spring according to aspects and embodiments described herein is described. DETAILED DESCRIPTION

[0023] Reference will now be made in more detail to various aspects and embodiments, one or more examples of which are shown in each of the accompanying drawings. In the following detailed description, the same reference numerals represent the same or similar components. The reference numerals used in the drawings are for illustration only.

[0024] Unless otherwise noted, features illustrated or described as part of one embodiment may be used alone or in combination with any other embodiment. The description of a portion or aspect in one embodiment also applies to the corresponding portion or aspect in another embodiment, and any aspect described may be combined with any other aspect or embodiment described herein unless otherwise noted. Each example is provided in an illustrative and non-limiting manner. Generally, only the differences with respect to the various embodiments are described. Although the figure numbers in the following description refer to Figures 1 to 5 The embodiments shown in the drawings are for illustration purposes only, but the descriptions are not limited to these embodiments unless explicitly stated.

[0025] Circuit breaker, opening spring and spring tension adjustment mechanism

[0026] Figure 1 A vacuum circuit breaker having a trip spring 110 and a spring tension adjustment mechanism according to aspects and embodiments described herein is shown.

[0027] The vacuum circuit breaker includes a vacuum circuit breaker unit 500 having a movable contact 510 configured to switch between an open position and a closed position; and a fixed contact 520 .

[0028] The vacuum circuit breaker further comprises a drive unit 100 coupled to the movable contact 510 for actuating movement between the closed position and the open position, the drive unit 100 comprising a trip spring 110, a first end of which is operably coupled to the movable contact 510 for biasing the movable contact 510 toward the open position.

[0029] The vacuum circuit breaker further includes a spring tension adjustment mechanism. The spring tension adjustment mechanism includes an adjustment actuator 120 configured to position the second end of the opening spring 110 at a plurality of positions corresponding to a plurality of lengths of the opening spring; and a rigid coupling rod 130 connecting the adjustment actuator 120 to the second end of the opening spring 110. The adjustment actuator 120 is arranged to deviate from the opening spring axis 170.

[0030] Advantageously, a circuit breaker is provided with a compact drive unit having an adjustable opening spring 110. As can be readily appreciated, an opening spring that is adjustable by a spring tension adjustment mechanism is very beneficial in a circuit breaker.

[0031] For example, during development, installation and / or maintenance of a circuit breaker, a spring tension adjustment mechanism can be used to determine an optimum or appropriate pretensioning force depending on the actual system friction, tolerance chain and equilibrium force distribution in the system, wherein individual tolerances and / or variations of components can be taken into account.

[0032] The spring tension adjustment mechanism can also be used to test the effect of different force settings on the kinematic system, and / or for optimization or individual adjustment of the spring mechanism to accommodate tolerances and kinematic variations in operating circuit breakers.

[0033] Therefore, it can be understood that by providing a spring tension adjustment mechanism, the tension, length, angle and / or pre-tension of the trip spring can be adjusted to ensure that the specifications are met regardless of any manufacturing tolerances or variations. As a result, the reliability and consistency of the circuit breaker can be improved.

[0034] In addition, both the opening spring and the spring tension mechanism can save space. Specifically, providing the spring tension mechanism at a position where the spring space is not occupied or the spring space is reduced has great benefits and saves space.

[0035] By arranging the spring tension adjustment mechanism offset from the opening spring axis, the spring tension adjustment mechanism, in particular the adjustment actuator, is outside the design space of the spring, specifically, outside the space defined by the spring axis and the spring coil diameter.

[0036] Since there is more space in the spring itself, longer springs can be used. Longer springs may be able to accommodate higher pretensioning forces at a given spring rate, or to accommodate lower spring rates for a given pretensioning force. For the opening spring, the pretensioning force can be selected to compensate for the (mainly vacuum-induced) forces acting on the movable contact element towards the closed position. For longer springs, this pretensioning force can be achieved at a lower spring rate, so that at this spring length a lower spring rate can be used to meet the required pretensioning force. One advantage of a lower spring rate is that it reduces the energy consumption during actuation of the movable contact element.

[0037] At the same time, the spring tension adjustment mechanism saves space because it does not take up space of the opening spring, especially because it does not operate along the opening spring axis to stretch / tension the opening spring, but is arranged offset from the opening spring axis.

[0038] Thus, a compact, energy-saving and adjustable circuit breaker is provided.

[0039] In one example, the spring tension mechanism is configured to adjust and / or change one or more of the tension, length, pre-tensioning force and / or disconnected position angle of the trip spring 110 (i.e., when the movable contact is in the disconnected position, for example relative to the operating rod 150).

[0040] It would be advantageous to provide a circuit breaker having an adjustable and space-saving opening spring, particularly with regard to the space available for the opening spring and the spring tension adjustment mechanism.

[0041] Free length state, pre-tensioned state and tensioned state

[0042] Figure 2 The drive unit is shown with the opening spring in a free-length state. Figure 3 The drive unit is shown with the opening spring in a pre-tensioned state. Figure 4 The drive unit is shown with the opening spring in the tensioned position.

[0043] It can be understood that there are multiple states of the opening spring, including a free length state, a pre-tensioned state and a tensioned state.

[0044] It can be understood that when the opening spring 110 is in a free length state, the length of the opening spring 110 is the free length, so the opening spring 110 is in a balanced state and basically generates no force.

[0045] Generally, it is preferred that the free length state can be achieved by the drive unit. The free length state is useful, for example, for inserting or removing the opening spring 110 .

[0046] Figure 2An example of a drive unit that obtains a spring free length state is shown. Here, the free length state is achieved by keeping the drive unit in a configuration corresponding to the disconnected position of the movable contact, such as Figure 2 As shown, this is achieved by the rod 150 being in a rotational position corresponding to the disconnected position of the movable contact. In other words, the angle between the operating rod 150 and the opening spring (or the opening spring axis 170) is the disconnected position angle.

[0047] The drive unit may be blocked and / or disconnected from the vacuum interrupter unit in this state, so that the drive unit is stably held in this configuration, but the movable contact is pulled towards the closed position by the vacuum of the vacuum interrupter unit.

[0048] like Figure 2 As further shown in FIG. 1 , the free length state can be achieved by releasing the spring tension adjustment unit.

[0049] Figure 3 A drive unit with an opening spring in a pre-tensioned state is shown. It will be appreciated that when the opening spring 110 is in the pre-tensioned state, the length of the opening spring 110 is a pre-tensioned length, which is longer than the free length, so that the opening spring 110 generates a force that biases the movable contact element toward the open position. The force generated in the pre-tensioned state is typically predetermined (calibrated) to match or overcome the force of the vacuum of the vacuum circuit breaker unit pulling the movable contact toward the closed position.

[0050] Generally, it is preferred that when the circuit breaker is in the disconnected configuration (when the drive unit is in the configuration corresponding to the disconnected position of the movable contact, such as Figure 3 As shown, the rod 150 is in a rotational position corresponding to the disconnected position of the movable contact), the drive unit can reach a pre-tensioned state. Therefore, in the disconnected configuration of the circuit breaker, the opening spring may generate a reaction force that overcomes the force pulling the movable contact toward the closed position.

[0051] The pre-tension state of the spring can be achieved by properly adjusting the spring adjustment mechanism, such as Figure 3 shown.

[0052] Figure 4 1 shows a drive unit, wherein the opening spring is in a tensioned position. It is understood that when the opening spring 110 is in a tensioned state, the length of the opening spring 110 is a tensioned length, which is longer than the pre-tensioned length. When the circuit breaker is in a closed configuration (when the drive unit is in a configuration corresponding to the closed position of the movable contact, as shown in FIG. Figure 4 As shown, the lever 150 is in a rotational position corresponding to the closed position of the movable contact), the tensioned state can be obtained.

[0053] Drive unit

[0054] It is understood that the drive unit 100 can be configured to drive the drive shaft 140 to rotate, in particular for moving the movable contact 510 between the closed position and the open position. The drive unit 100 can be bidirectionally manipulated / driven to move, from the open position to the closed position and from the closed position to the open position.

[0055] In one example, the driving unit may include a driving actuator (not shown) for driving the driving shaft 140 to move the movable contact between the closed position and the open position. In one embodiment, the driving actuator is different from the opening spring 110 .

[0056] Typically, the drive actuator of the drive unit can be implemented as a mechanical spring and / or an electromagnetic actuator. Advantageously, the force applied by the hand, for example a force in the range of 0.1 to 100 N (Newton), is reinforced or amplified by the drive unit. In one example, the drive actuator of the drive unit can provide at least 50 J (Joules) and / or at most 500 J of energy.

[0057] Opening spring

[0058] The purpose of the opening spring 110 is to provide a well-calibrated force acting on the movable contact 510 in the opening configuration of the circuit breaker (when the movable contact 510 is in the opening position) to stably hold the movable contact 510 in the opening position against any force (such as vacuum force) acting on the movable contact 510. To this end, in the opening configuration of the circuit breaker, the opening spring 110 is pre-tensioned.

[0059] According to one embodiment, the pretension length of the opening spring 110 is the length of the opening spring 110 when the movable contact 510 is in the open position and the adjustment mechanism is adjusted so that the spring has a predetermined pretension force according to the circuit breaker specification.

[0060] In one example, as described above, the pre-tension length of the opening spring 110 is adjusted using a spring tension adjustment unit to match or overcome the force of the vacuum of the vacuum circuit breaker unit pulling the movable contact toward the closed position.

[0061] In one example, the opening spring 110 can store energy when the movable contact 510 is in the closed position (and when the opening spring is in the tensioned position). In a specific example, the opening spring 110 assists in the circuit breaking operation, in particular by providing the movable contact with the energy stored when the movable contact 510 is in the closed position during the circuit breaking operation. On the other hand, the main energy source during the circuit breaking operation is usually a dedicated drive spring separate from the opening spring.

[0062] During the breaking operation, the contact spring can form the mechanical energy or kinetic energy (main supply source) of the breaking operation. The contact spring can be arranged in the movable contact assembly (for example, arranged on the corresponding movable contact 510), and the contact spring can be in a compressed state when the movable contact 510 is in the closed position.

[0063] In one example, at the beginning of the breaking operation, the contribution of the mechanical energy or kinetic energy supply source from the opening spring may be smaller than the mechanical energy or kinetic energy source from the contact spring.

[0064] In one example, during the end of a breaking operation, when the movable contact 510 is closer to the open position than the closed position, the opening spring 110 may take over from the contact spring to hold or maintain the movable contact 510 in the open position.

[0065] According to one embodiment, the opening spring 110 is arranged obliquely / diagonally in the cubic compartment (i.e., the spring axis 170 is not parallel to the side wall of the compartment). Preferably, the spring axis 170 of the opening spring 110 is arranged at an angle of at least 15° and at most 45° relative to the side wall of the compartment. In one embodiment, the spring axis 170 of the opening spring 110 is inclined relative to the side wall of the compartment. The inclination may be towards a line connecting the diagonals of the compartment, and may preferably be closer to this line than to the corresponding side wall.

[0066] The compartment may belong to the drive unit 100 and / or may include the frame 190 .

[0067] It is easy to understand that the maximum possible tension length can thus be utilized. In particular, it is easy to understand that a trip spring with a lower spring rate can be used, which requires a greater tension length to achieve an equally high pretensioning force.

[0068] It can be further understood that a trip spring with a lower spring stiffness helps to reduce the energy consumption of the energy input source.

[0069] According to one embodiment, the spring space comprises a plurality of volumes.

[0070] Each volume among the multiple volumes may be understood as a volume occupied by the opening spring 110 when the opening spring is at a corresponding length among the multiple lengths of the opening spring 110 .

[0071] Each volume in the plurality of volumes may be understood as a volume occupied by the opening spring 110 when the movable contact is in the open position.

[0072] Each of the multiple volumes may be understood as a volume occupied by the opening spring 110 installed in the driving unit 100 .

[0073] According to one embodiment, the multiple lengths of the opening spring 110 include multiple pre-tensioned lengths and a free length.

[0074] Advantageously, by using a spring tension adjustment mechanism, the opening spring can be adjusted from a free length to a plurality of pre-tensioned lengths.

[0075] The pre-tensioning length can be understood as the length of the opening spring 110 when the movable contact 510 is in the disconnected position. The pre-tensioning length can be understood as the length of the opening spring 110 when the opening spring 110 holds and / or maintains the movable contact 510 in the disconnected position, in particular through the operating rod 150 and / or through the operating shaft 140.

[0076] The free length is understood to be the length of the opening spring 110 when the opening spring is (completely) untensioned and / or when no force is applied to the second end via / from the rigid coupling rod 130 .

[0077] Adjustment actuator

[0078] According to the present invention, the drive unit comprises a spring tension adjustment mechanism. The spring tension adjustment mechanism comprises an adjustment actuator 120, which is configured to adjust the second end ( Figure 1-4 The spring tension adjustment mechanism further comprises a rigid coupling rod 130 connecting the adjustment actuator 120 to the second end of the opening spring 110. The adjustment actuator 120 is arranged offset from the opening spring axis 170. The offset arrangement allows a space-saving design.

[0079] The adjustment actuator 120 may define an actuator axis 180 and may include a movable adjustment element that can move along the actuator axis 180 when the adjustment actuator 120 is actuated to adjust the spring pretension. For example, the adjustment actuator 120 may include a bolt, and the movable adjustment element may be a nut with an internal thread, which is suitable for moving up and down along the actuator axis 180 when the bolt is rotated. The nut can be connected to the rigid coupling rod 130 (for example, by a claw). The nut can, for example, be part of an actuator connection structure 230, which is arranged on the rigid coupling rod 130 and connects the rigid coupling rod 130 to the adjustment actuator 120. The rigid coupling rod 130 is connected to the opening spring 110. Specifically, the rigid coupling rod 130 is connected to the second end of the opening spring 110 via the rod and spring connection structure 210.

[0080] According to one embodiment, the adjustment actuator 120 is arranged outside the spring space, ie the space enclosed by the spring, and also outside the space of the virtual extension of the spring along the spring axis.

[0081] According to one embodiment, the actuation axis 180 of the adjustment actuator 120 is within 45 degrees relative to the parallel line of the opening spring axis 170 (the actuation axis 180 deviates within 45 degrees relative to the position parallel to the opening spring axis 170), preferably within 30 degrees, and more preferably within 20 degrees. This arrangement of the actuation axis is beneficial for the reaction force acting on the components of the spring tension adjustment mechanism when opening or closing the circuit breaker.

[0082] Advantageously, if the center lines of the actuator and the opening spring are substantially parallel, the bending moment in the regulating actuator can be reduced.

[0083] According to one embodiment, the actuation length of the adjustment actuator 120 is greater than the length of the opening spring 110 extending from the free length to the pre-tensioned length.

[0084] According to one embodiment, the adjustment actuator 120 is fixedly mounted on the frame 190 via a fixed attachment 160. The fixed attachment 160 may be understood to be fixedly attached to the frame 190.

[0085] According to one embodiment, the adjustment actuator 120 is arranged outside the space of the opening spring 110 and outside the tension direction of the opening spring 110 , outside the opening spring axis 170 and the diameter of the opening spring 110 .

[0086] Advantageously, the adjusting actuator for adjusting the opening spring is arranged to maximize the spring space, so that the maximum possible tension length can be utilized and an opening spring with a lower spring rate can be used.

[0087] According to one embodiment, the adjustment actuator is configured to be connectable to the rigid link at a plurality of positions along the adjustment length of the adjustment actuator for positioning the opening spring at a plurality of positions.

[0088] According to one embodiment, the actuatable distance of the regulating actuator 120 is longer than the length of the brake spring 110 extending from the free length to the pre-tensioned length.

[0089] Advantageously, the opening spring can be extended from a free length beyond a pre-tensioning length, so that the opening spring can be adjusted to exceed a pre-tensioning length.

[0090] In one example, the adjustment actuator 120 is a bolt, in particular a tensioning bolt or a bolt for tensioning the opening spring 110. In other examples, the adjustment actuator 120 is a rack and pinion, a screw jack or other positioning device, and / or is electrically actuated and / or operator / manually actuated.

[0091] In one example, the adjustment actuator 120 (eg, a tension bolt) is mounted offset relative to the rod and spring connection structure 210 .

[0092] In one example, the adjustment actuator 120 may be operated to increase or decrease the tension of the trip spring 110 .

[0093] In a specific example, the adjustment actuator 120 is a tension bolt that can be tightened or loosened to increase or decrease the tension of the opening spring 110 , respectively.

[0094] In one example, the actuatable portion 410 of the adjustment actuator 120 may be accessible from a side or outside of the compartment or frame 190 of the drive unit 100 .

[0095] Helpfully, the spring tension can be easily adjusted without disassembling the drive unit.

[0096] In the example where the adjustment actuator 120 is a tension bolt, the actuatable portion 410 of the adjustment actuator 120 may be a head of the tension bolt that is accessible from outside the frame 190 of the drive unit 100 .

[0097] The benefit is that spring tension can be easily adjusted using standard tools, eliminating the need for time-consuming disassembly.

[0098] Rigid connecting rod

[0099] The adjusting actuator 120 is configured to position the second end of the opening spring 110 at a plurality of positions corresponding to the plurality of lengths of the opening spring. To this end, a rigid coupling rod 130 connects the adjusting actuator 120 (specifically, the movable part of the adjusting actuator, such as a nut) to the second end of the opening spring 110.

[0100] According to one embodiment, the rigid coupling rod 130 is used to convert the movement between each pair of positions in the multiple postures / positions of the adjustment actuator 120 (especially its movable part) into the movement between corresponding pairs of positions in the multiple positions of the second end of the opening spring 110.

[0101] According to one embodiment, the rigid coupling rod 130 is configured to convert the movement of the regulating actuator 120 into a position change of the second end of the opening spring 110 through the lever movement of the rigid coupling rod 130 , in particular, using the base connection structure 220 as the fulcrum of the lever movement.

[0102] According to one embodiment, the rigid coupling rod 130 is fixed to the frame 190 in such a way that for each configuration of the adjustment actuator 120 (e.g., each position of its movable part), a unique corresponding position of the rigid coupling rod 130 is defined. Therefore, a unique corresponding position of the second end of the opening spring 110 can also be defined according to the configuration of the adjustment actuator 120.

[0103] According to one embodiment, the rigid coupling rod 130 is fixed to the frame 190 via a base connection structure 220. The base connection structure 220 may include rotational degrees of freedom, translational degrees of freedom, or both (e.g., Figure 1-5 shown).

[0104] According to a specific embodiment, the rigid connecting rod 130 is fixed to the frame 190 via a rotatable base connecting structure 220 so that the movement between each pair of positions in the multiple positions of the adjusting actuator 120 is converted into the movement between corresponding pairs of positions in the multiple positions of the second end of the opening spring 110 through the lever movement of the rigid connecting rod 130, wherein the base connecting structure 220 serves as a fulcrum for the lever movement.

[0105] In one example, the rigid coupling rod 130 is a tensioning rod and / or a rod that transmits a tensioning force (the force provided by the adjustment actuator 120 ) to the opening spring 110 .

[0106] In one example, the rigid coupling rod 130 is fixed to the frame 190 and / or is hinged at the base connection structure 220 .

[0107] In one example, the rigid coupling rod 130 is an articulated tension rod. In one example, the rigid coupling rod 130 includes a rotatable connection structure, such as a rotating pin, that couples the rigid coupling rod 130 to the adjustment actuator 120 .

[0108] Base connection structure slot and spring positioning slot

[0109] Figure 5 A drive unit having a slotted hole and a spring retaining slot according to embodiments and examples described herein is shown.

[0110] According to one embodiment, when the length of the opening spring 110 is a first pre-tensioning length, the base connection structure 220 is located at the first end of the slotted hole 310 , and when the length of the opening spring 110 is a second pre-tensioning length, the base connection structure 220 is located at the second end of the slotted hole 310 .

[0111] According to an embodiment that can be combined with other embodiments, the second end of the slotted hole 310 is closer to the opening spring 110 than the first end of the slotted hole 310 , and the second pre-tensioning length is longer than the first pre-tensioning length.

[0112] According to one embodiment, the base connection structure 220 allows the rigid coupling rod 130 and / or spring to translate relative to the frame 190. Figure 5 As shown, this translational movement can be achieved by the base connection structure 220, which includes a slotted hole 310 in the rigid connecting rod 130, such as Figure 5 Here, the base connection structure 220 has a coupling protrusion in the frame 190, and the rigid coupling rod 130 has a slotted hole that allows sliding of the rigid coupling rod 130 in addition to rotation. This sliding allows sufficient freedom so that the rigid coupling rod 130 can slide along the slotted hole 310.

[0113] Alternatively, the coupling protrusion of the base connection structure 220 can be fixed to the rigid coupling rod 130 and can slide in the slotted hole of the frame 190 (in Figure 5 not shown).

[0114] According to one embodiment, the drive unit 100 comprises a spring positioning slot 320 , a portion of the spring adjustment mechanism is slidably arranged in the spring positioning slot 320 , and the portion of the spring adjustment mechanism is at least partially arranged in the spring positioning slot 320 .

[0115] According to one embodiment, the drive unit 100 comprises a spring positioning groove 320. A sliding member coupled to the second end of the opening spring 110 can slide along the spring positioning groove 320. Specifically, the sliding member can be a protrusion of the (rotational) rod and spring connection structure 210. The rigid coupling rod 130 is coupled to the second end of the opening spring 110. Thus, the rod and spring connection structure 210 can slide along the spring positioning groove 320.

[0116] According to one embodiment, the axis of the spring positioning groove 320 is parallel to the opening spring axis 170 (at least within a tolerance of 10°, preferably 5°, and even more preferably 2°). This configuration allows the opening spring axis 170 to remain substantially unchanged under spring adjustment.

[0117] According to one embodiment, the drive unit 100 includes a plurality of markings 330 arranged along the spring positioning groove 320. According to one embodiment, the plurality of markings 330 correspond to a plurality of pre-tensioning lengths of the opening spring 110. Therefore, advantageously, the opening spring can be easily adjusted or set to a desired pre-tensioning force.

[0118] According to one embodiment, the rotatable rod-spring connection structure 210 and the rotatable rod-actuator connection structure 230 are arranged on the rigid coupling rod 130 , and the rigid coupling rod 130 is connected to the opening spring 110 and the regulating actuator 120 , respectively.

[0119] In one example, the rod-and-spring connection structure 210 that couples the rigid coupling rod 130 to the trip spring 110 may slide within a spring positioning slot 320 that is located within the frame 190 of the circuit breaker.

[0120] In an alternative embodiment, the rigid coupling rod 130 is connected by rotating only the base connection structure 220 (e.g., without Figure 5 The slotted hole 310 shown in FIG. 1 is fixed to the frame 190. In this case, the spring positioning groove 320 can be omitted or replaced by a groove that follows the circular motion of the rod and spring connection structure 210 around the rotating base connection structure 220.

[0121] Rod-actuator connection structure, rod-spring connection structure and base connection structure

[0122] According to one embodiment, the base connection structure 220 is offset from the opening spring axis 170 .

[0123] According to one embodiment, the rigid coupling rod 130 is coupled to the adjustment actuator 120 at a rod-to-actuator connection 230 that is offset from a straight line connecting the rod-to-spring connection 210 and the base connection 220 .

[0124] According to one embodiment, the rod-to-spring connection structure 210 connects the rigid coupling rod 130 to the opening spring 110 , and the base connection structure 220 connects the rigid coupling rod 130 to the frame of the circuit breaker.

[0125] In one example, the adjustment actuator 120 is connected to the opening spring 110 via a rod and spring connection structure 210. In one example, the rod and spring connection structure 210 is a spring pin joint. In one example, the base connection structure 220 is a pivot pin joint.

[0126] Fastening attachments and frames

[0127] According to one embodiment, the circuit breaker includes a frame 190 .

[0128] In one example, the frame 190 at least partially surrounds the drive unit 100. In a specific example, the frame 190 at least partially forms a compartment in which the drive unit 100 is arranged.

[0129] According to one embodiment, the adjustment actuator 120 is fixed to the frame 190 via a fixed attachment 160 .

[0130] In one example, the fixed attachment 160 is mounted on the frame 190. In one example, the fixed attachment 160 includes a rotatable actuator and frame connection structure.

[0131] In one example, the adjustment actuator 120 is secured to the fixed attachment 160 via a rotatable actuator-to-frame connection structure.

[0132] According to one embodiment, the adjustment actuator 120 extends at least a length from the fixed attachment to the second end of the opening spring 110 (in a direction parallel to the opening spring axis 170 ) which is in a free length state.

[0133] Operating shaft and lever

[0134] According to one embodiment, the driving unit 100 includes an operating shaft 140 and an operating lever 150 .

[0135] The operating rod 150 may be understood to be mounted on the operating shaft 140 .

[0136] The opening spring 110 may be understood to be operatively connected to the vacuum circuit breaker unit 500 , in particular the movable contact 510 , via (at least) the operating rod 150 and / or the operating shaft 140 .

[0137] According to one embodiment, when the movable contact 510 is in the disconnected position, the operating rod 150 and the opening spring 110 are within 30 degrees of the mutually perpendicular position (the operating rod 150 and the opening spring 110 deviate from the mutually perpendicular position within 30 degrees), preferably within 20 degrees of the mutually perpendicular position, and more preferably within 10 degrees of the mutually perpendicular position.

[0138] Advantageously, in the disconnected position, the operating rod and the spring angle are substantially perpendicular, and the torque generated by the opening spring to hold the movable contact in the disconnected position is maximum.

[0139] According to one embodiment, when the movable contact 510 is in the closed position, the angle between the operating rod 150 and the opening spring axis 170 is less than 70 degrees, preferably less than 60 degrees, and more preferably less than 50 degrees.

[0140] Advantageously, in the closed position the lever and spring angles are smaller and the counter torque is reduced.

[0141] According to one embodiment, the operating shaft 140 and / or the operating rod 150 is used to transmit the opening force / disconnection force of the opening spring 110 to the movable contact 510, in particular, to move the movable contact to the disconnected position.

[0142] Method for tensioning the opening spring

[0143] Figure 6 A method of tensioning a trip spring according to aspects and embodiments described herein is shown.

[0144] According to one aspect, a method for tensioning an opening spring of a vacuum circuit breaker includes pre-tensioning the opening spring by starting / actuating an adjusting actuator (step 610 ).

[0145] In the example where the adjusting actuator is a tensioning bolt, the step of actuating the adjusting actuator to pre-tension the opening spring comprises tightening or loosening the tensioning bolt.

[0146] According to one embodiment, the method includes: setting the opening spring to a pre-tensioned length by actuating an adjusting actuator, the pre-tensioned length being different from a predetermined pre-tensioned length (step 620 ).

[0147] In the example where the adjusting actuator 120 is a tensioning bolt, the step of actuating the adjusting actuator to pre-tension the opening spring to a pre-tensioning length different from the predetermined pre-tensioning length includes tightening or loosening the tensioning bolt.

[0148] The predetermined pre-tensioning length may be understood as a pre-tensioning length determined before the circuit breaker is installed or assembled.

[0149] A pretensioning length different from a predetermined pretensioning length may be understood as a pretensioning length adapted to changes after installation and / or after assembly, in particular changes in the kinematic chain of the circuit breaker, for example in the kinematic chain of the drive unit 100 .

[0150] Other aspects of circuit breakers

[0151] Generally, a circuit breaker may be understood as a device suitable for controlling and protecting an electrical network. According to one aspect, the circuit breaker may be a vacuum circuit breaker.

[0152] In one example, it is understood that the rated operating voltage of the circuit breaker described herein exceeds 1 kV. For example, the circuit breaker may be a medium voltage circuit breaker and / or the rated operating voltage is in the range of 1 kV to 72 kV, preferably in the range of 10 kV to 42 kV.

[0153] In one example, it is understood that the rated operating current of the circuit breaker described herein is greater than 100A, preferably at least 400A and / or at most 5000A, and / or the short-circuit current exceeds 10kA rms, preferably at least 14kA rms (root mean square value) and / or at most 50kA rms (high short-circuit current load).

[0154] In one embodiment, the circuit breaker, in particular the vacuum circuit breaker unit 500, comprises a gas-tight housing. In one embodiment, the gas-tight housing is filled or configured to be filled with a dielectric. In one embodiment, the vacuum circuit breaker unit 500 further comprises at least one so-called vacuum bottle ( Figure 1). Each vacuum bottle is a corresponding airtight vacuum housing arranged in the housing of the vacuum circuit breaker unit 500. A pair (or more pairs) of circuit breaker contacts 510, 520 of the circuit breaker are arranged in a corresponding one of the at least one vacuum bottle, and the circuit breaker contacts 510, 520 are in an open configuration and are separated from each other by the vacuum in the corresponding vacuum bottle.

[0155] In one embodiment, the dielectric in the airtight housing of the circuit breaker unit 500 can be a dielectric gas, such as SF6, but more preferably a dielectric gas with a global warming potential less than SF6. In one example, the dielectric is air, dry air, N2, CO2, or a mixture of two or three of N2, O2 and CO2. In one example, the dielectric is air, fluoroketone and / or AirPlus TM In one embodiment, the dielectric is a mixture of air and / or fluoroketone. The dielectric may surround at least one vacuum bottle arranged in the housing of the circuit breaker unit 500.

[0156] In one embodiment, the drive unit 100 is arranged outside the airtight housing of the vacuum circuit breaker unit 500, and transmits the driving motion to the circuit breaker unit 500 (specifically to the movable contact 510) through the rotatable shaft 140 partially extending into the airtight housing. Advantageously, the accessibility of the drive unit 100 is improved.

[0157] Although the vacuum circuit breaker unit 500 including a movable contact 510 and a fixed contact 520 is described herein, the circuit breaker described herein may be understood to include a plurality of circuit breaker units, in particular three circuit breaker units, each circuit breaker unit including a movable contact and a fixed contact. Then, the contacts 510, 520 of each circuit breaker unit are arranged in separate airtight vacuum housings of the circuit breaker units. In one embodiment, all movable contacts of the vacuum circuit breaker unit 500 are actuated by the same drive unit through a common drive shaft.

[0158] Advantageously, a multi-phase circuit breaker is provided, in particular a circuit breaker for a three-phase circuit / network. The multi-phase circuit breaker may have a plurality of pairs of circuit breaker contacts 510, 520 (arranged in a plurality of corresponding vacuum bottles). These pairs of movable contacts 510 may be driven by a single common shaft 140.

[0159] Although the invention has been described and illustrated in detail in the drawings and the foregoing description, such description and illustration should be considered illustrative or exemplary rather than restrictive; the invention is not limited to the disclosed embodiments. Other variations of the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention based on a study of the drawings, the disclosure, and the appended claims.

[0160] In the claims, the words "comprising / consisting of..." do not exclude other elements, and the term "one" does not exclude a plurality. A single element or another unit may perform the functions of several items listed in the claims. The fact that certain features are cited in different embodiments or dependent claims does not mean that the combination of these features cannot be used advantageously / effectively. Without departing from the spirit and scope of the present application, the scope of protection of the present application covers any possible combination of the features described in the various embodiments or in the dependent claims. The figure marks in the claims should not be interpreted as limiting the scope of the invention.

Claims

1. A vacuum circuit breaker, comprising: A vacuum circuit breaker unit (500) having a movable contact (510) configured to switch between an open position and a closed position; A drive unit (100) coupled to the movable contact (510) for actuating movement between a closed position and an open position, the drive unit (100) comprising an opening spring (110) operably connected to the movable contact (510) at a first end for biasing the movable contact (510) toward the open position; and A spring tension adjustment mechanism, the spring tension adjustment mechanism comprising: An adjustment actuator (120) configured to position the second end of the opening spring (110) at a plurality of positions corresponding to a plurality of lengths of the opening spring; and a rigid coupling rod (130) connecting the regulating actuator (120) to the second end of the opening spring (110); The regulating actuator (120) is arranged to be offset from the opening spring axis (170).

2. The vacuum circuit breaker according to claim 1, wherein: The regulating actuator (120) is arranged outside the spring space, and the spring space includes a plurality of volumes corresponding to the plurality of positions of the opening spring (110).

3. The vacuum circuit breaker according to claim 1 or 2, wherein: The opening spring (110) is arranged diagonally in the cubic compartment.

4. The vacuum circuit breaker according to claim 1 or 2, wherein: The multiple lengths of the opening spring (110) include a free length and multiple pre-tensioned lengths.

5. The vacuum circuit breaker according to claim 1 or 2, wherein: The rigid coupling rod (130) is anchored to the frame (190) via a rotatable base connection structure (220).

6. The vacuum circuit breaker according to claim 1 or 2, wherein: The rigid connecting rod (130) is anchored to the frame (190) via a rotatable base connection structure (220) and is used to convert the movement between each pair of positions in the multiple positions of the regulating actuator (120) into the movement between the corresponding pairs of positions in the multiple positions of the second end of the gate spring (110).

7. The vacuum circuit breaker according to claim 1, wherein: The rigid connecting rod (130) is anchored to the frame (190) via a rotatable base connecting structure (220), and is used to convert the movement between each pair of positions in a plurality of positions of the regulating actuator (120) into movement between corresponding pairs of positions in a plurality of positions of the second end of the gate spring (110) via the lever movement of the rigid connecting rod (130), wherein the base connecting structure (220) serves as a fulcrum for the lever movement.

8. The vacuum circuit breaker according to claim 7, wherein: The base connection structure (220) can achieve at least one item selected from the group consisting of the following items: - rotatable movement of the rigid connecting rod (130), and - Translational movement of the rigid connecting rod (130).

9. The vacuum circuit breaker according to claim 8, wherein: The base connection structure (220) is arranged to be offset from the opening spring axis (170).

10. The vacuum circuit breaker according to claim 9, wherein: When the length of the opening spring (110) is a first pre-tensioning length, the base connection structure (220) is located at the first end of the slotted hole (310); when the length of the opening spring (110) is a second pre-tensioning length, the base connection structure (220) is located at the second end of the slotted hole (310).

11. The vacuum circuit breaker according to claim 10, wherein: The second end of the slotted hole (310) is closer to the opening spring (110) than the first end of the slotted hole (310), and the second pre-tensioning length is longer than the first pre-tensioning length.

12. The vacuum circuit breaker according to claim 1 or 2, wherein: The drive unit (100) further comprises a spring positioning groove (320) and a sliding block connected to the second end of the opening spring (110), wherein the sliding block can slide along the spring positioning groove (320).

13. The vacuum circuit breaker according to claim 12, wherein: The axis of the spring positioning groove (320) is parallel to the axis of the opening spring (170).

14. The vacuum circuit breaker according to claim 12, wherein: The drive unit (100) further comprises a plurality of marks (330) arranged along the spring positioning groove (320), wherein the plurality of marks (330) correspond to a plurality of pre-tensioning lengths of the opening spring (110).

15. The vacuum circuit breaker according to claim 1 or 2, wherein: The drive unit (100) further comprises a rotatable rod and spring connection structure (210) respectively connecting the rigid connection rod (130) and the opening spring (110), and a rotatable rod and actuator connection structure (230) connecting the rigid connection rod (130) and the regulating actuator (120).

16. The vacuum circuit breaker according to claim 1 or 2, wherein: The drive unit (100) further comprises an operating shaft (140) and an operating rod (150) arranged on the operating shaft (140), wherein the opening spring (110) is operably connected to the vacuum circuit breaker unit via the operating rod (150) and the operating shaft (140).

17. The vacuum circuit breaker according to claim 16, wherein: When the movable contact (510) is in the disconnected position, the operating rod (150) and the opening spring (110) are within 30 degrees of a mutually vertical position.

18. The vacuum circuit breaker according to claim 1 or 2, wherein: The opening spring (110) is a tension spring.

19. A method for tensioning a trip spring of a vacuum circuit breaker, the vacuum circuit breaker comprising: A vacuum circuit breaker unit (500) having a movable contact (510) configured to switch between an open position and a closed position; A drive unit (100) coupled to the movable contact (510) for actuating movement between a closed position and an open position, the drive unit (100) comprising an opening spring (110) operably connected to the movable contact (510) at a first end for biasing the movable contact (510) toward the open position; and A spring tension adjustment mechanism, the spring tension adjustment mechanism comprising: An adjustment actuator (120) configured to position the second end of the opening spring (110) at a plurality of positions corresponding to a plurality of lengths of the opening spring; and a rigid coupling rod (130) connecting the regulating actuator (120) to the second end of the opening spring (110); The adjusting actuator (120) is arranged to deviate from the opening spring axis (170), and the method comprises pre-tensioning the opening spring by actuating the adjusting actuator.

20. The method according to claim 19, wherein: During the pre-tensioning period, the movable contact (510) remains in the open position.

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