Operating mechanism for a switching device

Abstract

The invention relates to an operating mechanism for a switching device (601) comprising a motor (1), an axially extending screw (701) and a spindle nut (702), wherein the screw (701) is connected to the motor (1) and configured to be rotated by the motor (1), the spindle nut (702) is movably engaged with the screw (701) and configured to be linearly moved along the screw (701) when the screw (701) is rotated, and the screw (701) comprises a chamfered thread end (706) which is insertable into the spindle nut (702), wherein the chamfered thread end (706) comprises a first chamfered surface (708) extending at a first angle (a) with respect to an axial extension of the screw (701) and a second chamfered surface (709) extending at a second angle (b) with respect to the axial extension of the screw (701), and the second angle (b) is greater than the first angle (a).

Description

Technical Field

[0001] This invention relates to an operating mechanism for a switching device, comprising a motor, an axially extending screw, and a spindle nut, wherein the screw is connected to and configured to be rotated by the motor, and the spindle nut is movably engaged with the screw and configured to move linearly along the screw as the screw rotates. The invention also relates to a switching device comprising a movable contact and an operating mechanism, wherein the operating mechanism is configured to operate the movable contact to perform an opening or closing operation of the switching device. Background Technology

[0002] The drive mechanism for switching devices (such as grounding switches with short-circuit closing capability) typically includes a spindle drive mechanism comprising an axially extending screw and a spindle nut, the spindle nut having corresponding threads for engaging with the screw. At the end of the switching operation, the spindle nut typically disengages from the screw threads. Therefore, for subsequent operations, the spindle nut needs to re-engage with the screw threads. However, cross-threading can occur, causing the spindle nut to jam, preventing the operating mechanism from performing the switching operation.

[0003] This misalignment occurs particularly during re-engagement when the threads of the screw and spindle nut are not properly aligned in the corresponding parts of the screw and spindle nut being engaged or tightened. Therefore, to improve alignment, the threads of such threaded connections are typically chamfered at a 45° angle. However, simply applying a 45° chamfer to the threads of a threaded connection is not reliably sufficient to prevent the misalignment. In fact, due to the 45° chamfer, the external thread of the screw and the internal thread of the spindle nut are often displaced relative to each other. This typically results in the end or beginning of the external thread of the screw being radially above the internal thread of the spindle nut. If an attempt is made to screw the threads together at this point, jamming occurs. In summary, the known solutions in the prior art for re-engaging the screw and spindle nut of operating mechanisms (particularly for operating mechanisms of grounding switches) are unsatisfactory. Summary of the Invention

[0004] Therefore, the object of the present invention is to provide an operating mechanism for a switching device that allows the screw to re-engage with the spindle nut without thread mis-threading.

[0005] The objective of this invention is achieved through the features of the independent claims. Preferred embodiments are detailed in the dependent claims.

[0006] Therefore, this objective is achieved by an operating mechanism for the switching device, the operating mechanism comprising: The motor, the axially extending screw, and the spindle nut, among which... The screw is connected to the motor and configured to be rotated by the motor. The spindle nut is movably engaged with the screw, and the spindle nut is configured to move linearly along the screw as it rotates. The screw includes a chamfered threaded end that can be inserted into a spindle nut, wherein the chamfered threaded end includes a first chamfered surface extending at a first angle relative to the axial extension of the screw and a second chamfered surface extending at a second angle relative to the axial extension of the screw, and the second angle is greater than the first angle.

[0007] Therefore, this solution proposes adding a second chamfer (i.e., a second chamfer surface) in addition to the usual first chamfer (i.e., the first chamfer surface), thereby preventing thread mis-threading during re-engagement or reconnection of the screw and the spindle nut. This proposed double-angled second chamfer prevents the end of the screw's usual external thread from radially positioned above the spindle nut's usual internal thread. Due to the second angle of the second chamfer surface, the end of the external thread thus moves towards the chamfer surface of the internal thread during re-engagement. Using this solution, thread mis-threading is effectively prevented when the threads are screwed together accordingly during reconnection of the screw and the spindle nut.

[0008] Normally, right-hand threads are turned counterclockwise until a typical click is heard indicating that the corresponding threads are reconnected. Once the click is heard, the threads are aligned, and the threads of the screw and the spindle nut can be engaged by clockwise rotation without thread misalignment as in milling. However, in prior art solutions, before the click, the end or beginning of the external thread may be radially above the internal thread. This is where thread misalignment occurs in prior art solutions. If the threads are then attempted to be screwed together, jamming occurs. With the proposed double-angle chamfer on the external thread, the situation where the end of the external thread is radially above the internal thread can be prevented, thus preventing thread misalignment.

[0009] This double-angle chamfer on the screw, preferably on the external thread of the screw, is much simpler in terms of specification and manufacturing. The double-angle chamfer can be applied during the initial turning process before cutting the actual thread. Therefore, applying this double-angle chamfer to the spindle of an operating mechanism for a grounding switch with short-circuit closing capability, such as that described previously, can solve the problem of re-engaging the spindle, which in turn reduces operating and maintenance costs by increasing system uptime.

[0010] As described above, the proposed operating mechanism can be applied to any switching device in which the screw and spindle nut re-engage, such as a grounding switch. In this respect, re-engagement preferably refers to the insertion of the chamfered thread end into the spindle nut such that the rotation of the screw upon insertion causes the spindle nut to move linearly. The first chamfered surface and / or the second chamfered surface preferably extend circumferentially about an axis defined by the axially extending screw. Therefore, the first chamfered surface and the second chamfered surface are inclined at a first angle and a second angle relative to said axis, respectively.

[0011] According to a preferred embodiment, the first angle is ≥30° and ≤50°, preferably 45°, and / or the second angle is ≥55° and ≤85°, preferably 75°. More preferably, the first angle is ≥35° or ≥40° and / or ≤50°, and / or the second angle is ≥60°, ≥65° and ≤80°. More preferably, the first angle and / or the second angle can increase with the axial extension of the first chamfered surface and / or the second chamfered surface. For example, the first angle can increase from 30° to 50°.

[0012] In another preferred embodiment, in the axial direction toward the end of the chamfered thread, the end of the chamfered thread first tapers with a first chamfered surface and then tapers with a second chamfered surface. Therefore, in the axial direction toward the end of the chamfered thread, the screw first includes a first chamfered surface that tapers at a first angle, and then the screw includes a second chamfered surface that tapers at a second angle. In other words, the end of the chamfered thread preferably becomes sharper in the axial direction toward the end of the chamfered thread.

[0013] According to another preferred embodiment, the first chamfered surface seamlessly transitions to the second chamfered surface in the axial direction toward the end of the chamfered thread. The first and second chamfered surfaces are preferably arranged sequentially, sequentially, and / or side-by-side in the axial direction. Preferably, in an axial top view of the end of the chamfered thread, the first and second chamfered surfaces extend over the full radial extension of the end of the chamfered thread.

[0014] In another preferred embodiment, the first chamfer surface and / or the second chamfer surface extend in a linear or convex manner in the axial direction toward the end of the chamfered thread. Preferably, in an axial top view of the end of the chamfered thread, the first chamfer surface and / or the second chamfer surface extend between a radially inner end and a radially outer end, such that they extend in a linear or convex manner in the radial direction.

[0015] According to another preferred embodiment, the spindle nut includes an internal thread with threaded flanks, and the second angle deviates from, coincides with, is equal to, or is unequal to the angle of the threaded flanks, particularly relative to the axial extension of the spindle nut and / or screw. This measure effectively avoids the aforementioned thread mis-threading.

[0016] In another preferred embodiment, the first chamfered surface extends ≥180°, preferably ≥270° and / or <360° around the end of the chamfered thread, and / or the second chamfered surface extends ≥180°, preferably ≥270° and / or <360° around the end of the chamfered thread. Preferably, in an axial top view of the end of the chamfered thread, the first chamfered surface and / or the second chamfered surface extend the angle circumferentially around the end of the chamfered thread.

[0017] According to another preferred embodiment, only the last thread of the screw, particularly the chamfered end of the thread, includes a first chamfered surface and a second chamfered surface. Preferably, the screw and / or spindle nut includes a plurality of corresponding threads extending in a helical manner. Thus, the screw preferably includes similarly machined threads having the same radial diameter and the same threads extending axially, wherein only this thread of the screw includes the first chamfered surface and the second chamfered surface.

[0018] In another preferred embodiment, the chamfered thread end includes a third chamfered surface that extends at a third angle relative to the axial extension of the screw, and the third angle is greater than the second angle. A second chamfered surface is preferably arranged between the first and third chamfered surfaces in the radial and / or axial directions. This three-angle chamfering method more effectively prevents thread misalignment.

[0019] According to another preferred embodiment, the screw includes external threads, particularly a plurality of helically extending external threads, the plurality of helically extending external threads including chamfered thread ends, and the spindle nut includes internal threads corresponding to the external threads, particularly a plurality of helically extending internal threads. The chamfered surfaces of the external and internal threads preferably correspond to each other and / or extend at the same or approximately the same angle.

[0020] In another preferred embodiment, the operating mechanism includes a rotatable output shaft configured to perform the opening or closing operation of the switching device by rotation, and kinematically connected to a main shaft nut. The rotatable output shaft may also be referred to as an output hub or main hub, and is designed to perform the opening or closing operation of the switching device by rotation.

[0021] The object of the present invention is further achieved by a switching device comprising a movable contact and the aforementioned operating mechanism, wherein the operating mechanism is configured to operate the movable contact to perform an opening or closing operation of the switching device. The switching device (sometimes also called a switching apparatus) may include two contacts, one of which is movable relative to the other. The movable contact can move between a closed position where the contacts are electrically connected and an open position where the contacts are not connected. The movable contact may be configured as a tulip-shaped contact, and the other contact, such as a fixed contact, may be configured as a plug contact, or vice versa. Moreover, the two contacts may be arranged to be movable relative to each other.

[0022] In another preferred embodiment, the switching device is provided as a gas-insulated switchgear with short-circuit capability, such as a grounding switch, disconnecting switch, disconnecting and grounding switch, and / or fast grounding switch. The grounding switch or fast grounding switch for interrupting non-short-circuit currents is preferably provided as a device designed to interrupt only non-short-circuit currents, particularly a disconnecting switch, especially a high-voltage disconnecting switch, or the aforementioned grounding switch, especially a make-proof earthing switch, or a medium- or high-voltage gas-insulated switchgear or GIS including such a device. In contrast to non-short-circuit current, the term "short-circuit current" can be understood as the current that establishes itself in a first transient phase of at most about three seconds from the moment a high-voltage component in a high-voltage power grid is grounded. According to this definition, the term "non-short-circuit current" preferably refers to any current that does not conform to the definition of "short-circuit current" given above.

[0023] Generally, disconnecting switches or grounding switches (also known as grounding knife switches) are understood as protective devices included in switchgear assemblies such as circuit breakers and isolators. When a circuit breaker is removed and deactivated, the grounding switch automatically grounds a portion of the busbar adjacent to the circuit breaker. For isolators, when the isolator isolates the circuit, the grounding switch contacts the busbar, thereby releasing any charge that may have accumulated there. For example, grounding switches in switchgear are used to ground residual charge in power lines after they have been disconnected from their power source. After a circuit has been disconnected or broken by a circuit breaker or isolator, residual charge often remains in the circuit. Grounding switches are typically provided to discharge this charge.

[0024] These disconnecting switches or grounding switches are typically designed to withstand short circuits. Disconnecting switches or grounding switches in substations usually have the ability to form short circuits to protect other electrical installations from damage. Disconnecting switches or grounding switches are often used in conjunction with several high-voltage switchgear units and also serve as protective devices during thorough overhauls of high-voltage electrical facilities. Attached Figure Description

[0025] These and other aspects of the invention will become apparent and elucidated with reference to the embodiments described below.

[0026] In the attached diagram: Figure 1 This is a schematic diagram showing a partial structure of the operating mechanism according to a preferred embodiment; Figure 2 It shows an observation from another perspective. Figure 1 A schematic diagram of a partial structure of the operating mechanism; Figure 3 It shows an observation from yet another perspective. Figure 1 A schematic diagram of a partial structure of the operating mechanism; Figure 4 It is shown in a partial sectional side view. Figure 1 A technical drawing of a partial structure of the operating mechanism, in which the screw is being inserted into the spindle nut; Figure 5a yes Figure 4 A partial sectional side view of the screw being inserted into the spindle nut; Figure 5b yes Figure 5a Local structure; Figure 6a yes Figure 5a A top view of the chamfered thread end of the screw; and Figure 6b yes Figure 5a A partial side view of the screw. Detailed Implementation

[0027] The implementation and use of the proposed solution are discussed in detail below. However, it is conceivable that the specific implementation methods discussed herein are merely intended to illustrate specific ways of implementing and using the proposed solution, and are not intended to limit the scope of protection of the proposed solution.

[0028] When describing the structure and position of components, directional expressions (such as "top," "bottom," "upper," "lower," "clockwise," and "counterclockwise") are not absolute but relative. These directional expressions are appropriate when the components are arranged as shown in the figures, but they should be changed accordingly when the positions of these components in the figures change.

[0029] Furthermore, unless otherwise stated and defined, terms such as “installed to” and “connected to” should be interpreted broadly. For example, “connected to” can mean “fixedly connected to,” “removably connected to,” or “integrally connected to,” can mean “mechanically connected to” or “electrically connected to,” and can mean “directly connected to,” “indirectly connected to,” or “associated with (something) under some action.” The specific meaning of the above terms will be understood by those skilled in the art depending on the specific circumstances.

[0030] It is conceivable that the switching device 601 used in the operating mechanism includes, but is not limited to, grounding switches, disconnecting switches, disconnecting and grounding switches, and fast grounding switches of gas-insulated switchgear (GIS). See below for reference. Figures 1 to 3 The specific structure of the operating mechanism according to a preferred embodiment is described. Furthermore, other embodiments are possible even if not described.

[0031] like Figures 1 to 3 As shown, the operating mechanism mainly includes a base support 8, a power module, an energy storage module, and a drive module, each of which is mounted on the base support 8. The power module mainly includes a motor 1 and a screw-nut transmission device connected to the motor 1. More specifically, the motor 1, which provides power, is fixedly mounted on the base support 8 and configured to transmit power to the screw-nut transmission device by means of a first transmission gear 101 fixedly sleeved on the output shaft of the motor 1 and a second transmission gear 6 engaging with the first transmission gear 101.

[0032] The screw and nut drive includes components such as an axially extending screw 701, a main nut 702, a protrusion 703, a limiting rod 704, and a micro switch 705. The two ends of the screw 701 are rotatably mounted to a base support 8 via, for example, bearings. A second transmission gear 6 is sleeved on the screw 701 and is non-rotatable relative to the screw 701, to drive the screw 701 to rotate under the drive of a motor 1. It is conceivable that the type of screw 701 includes, but is not limited to, a ball screw or a trapezoidal screw. The nut 702 is sleeved on the screw 701 and is capable of linear movement along the screw 701 as the screw 701 rotates.

[0033] Furthermore, each of the top and bottom surfaces of the nut 702 is provided with a protrusion 703, such as a protruding pin integrally formed on the nut 702, for actuating the energy storage rod 13, as described below. A limiting rod 704 is mounted to the base support 8 and parallel to the screw 701 to limit the position of the nut 702 as it moves along the screw 701, thereby preventing rotation of the nut 702. A micro switch 705 is mounted to the limiting rod 704 and adjacent to both ends of the screw 701 to send a control signal, such as a stop signal, to the motor 1 when the nut 702 moves to contact the micro switch 705.

[0034] The energy storage module includes two energy storage rods 13 and an energy storage spring 4 mounted to a spring support. More specifically, each energy storage rod 13 is fitted onto the output shaft 11 by means of, for example, a first bearing / sleeve 5 and is rotatable relative to the output shaft 11, and is configured to present an approximately Y-shape. That is, the energy storage rod 13 includes a first push arm 131 and a second push arm 132, which are arranged symmetrically with respect to each other in an approximately V-shape, and are rotatable by being pushed by a protrusion 703 of a nut 702, and the end of the energy storage rod 13 opposite to the two push arms is provided with an opening through which a connecting pin 2 passes.

[0035] The spring support includes a first spring support 301 mounted to the base support 8 and a second spring support 302 opposite to the first spring support 301 and movable toward or away from the first spring support 301. A spring 4 is helically arranged on a guide rod 304 between the first spring support 301 and the second spring support 302 to be compressed between the first spring support 301 and the second spring support 302 to store energy. The second spring support 302 is integrally provided with two connecting plates 303 projecting in a direction away from the first spring support 301. Each connecting plate 303 is provided with an opening through which a connecting pin 2 passes, such that two energy storage rods 13 are pivotally connected to the spring 4 by means of the connecting pin 2.

[0036] In the illustrated embodiment, two connecting plates 303 are arranged between two energy storage rods 13, and a bushing 14 arranged between the two connecting plates 303 is fitted onto the connecting pin 2. That is, the connecting pin 2 passes through the lower energy storage rod 13, the lower connecting plate 303, the bushing 14, the upper connecting plate 303, and the upper energy storage rod 13 sequentially from bottom to top. Therefore, when the energy storage rod 13 is pushed to rotate by the nut 702 under the drive of the power module, the energy storage rod 13 can drive the spring support and the spring 4 to rotate through the connecting pin 2, so that the spring 4 is compressed to store energy.

[0037] The drive module includes a drive rod 12 and an output shaft 11. More specifically, both ends of the output shaft 11 are rotatably mounted to the base support 8 via, for example, second bearings 15, and the output shaft 11 is connected to the movable contact 602 of the switching device 601, such that rotation of the output shaft 11 drives movement of the movable contact 602 to realize the opening and closing operation of the switching device 601. The drive rod 12 is sleeved on the output shaft 11 via, for example, splines 111 (such as external splines formed on the output shaft 11 and internal splines formed on the drive rod 12) and is non-rotatable relative to the output shaft 11 to drive the output shaft 11 to rotate, and the drive rod 12 is configured to present a generally V-shape.

[0038] That is, the drive rod 12 includes a third push arm 121 and a fourth push arm 122, which are arranged approximately V-shaped symmetrically with respect to each other and can be rotated by the connecting pin 2, specifically by the bushing 14 arranged on the connecting pin 2. In the illustrated embodiment, two energy storage rods 13 sleeved on the output shaft 11 are respectively arranged on both sides of the drive rod 12. That is, the output shaft 11 passes through the lower energy storage rod 13, the drive rod 12, and the upper energy storage rod 13 sequentially from bottom to top.

[0039] The damping module includes two absorbers 9 mounted to the base support 8 and a damping arm 10 fixedly connected to one end of the output shaft 11. The damping arm 10 contacts the corresponding absorber 9 during the final phase of the opening or closing operation of the switching device 601 to reduce the moving speed of the moving contact 602 during the final phase and to limit its position.

[0040] By coordinating parameters such as the angle between the two push arms of the energy storage rod 13, the angle between the two push arms of the drive rod 12, and the positions of the screw and nut transmission and the output shaft 11, the spring 4 is allowed to release energy only after it has rotated through its dead point position during at least one of the opening and closing operations of the switching device 601, and drive the drive rod 12 to rotate by means of the connecting pin 2, so as to realize the operation of the switching device 601 such as "rapid closing and rapid opening", "rapid closing and slow opening", and "rapid opening and slow closing".

[0041] Figure 4 It is shown in a partial sectional side view. Figure 1 A technical drawing of a partial structure of the operating mechanism, showing a screw 701 being inserted to engage with a spindle nut 702. The threads of the screw 701 and spindle nut 702, extending axially along axis 707, are not shown and are not yet engaged. Figure 4In this design, the screw 701 includes a chamfered threaded end 706 facing the spindle nut 702. Following this chamfered threaded end 706, an undisplayed thread of the screw 701 is arranged in an axial direction away from the spindle nut 702, as can be seen in later figures. This undisplayed thread is intended to extend radially away from the core diameter of the screw 701. Essentially the chamfered threaded end 706 of the last thread extends radially between the core diameter and the outer diameter of the screw 701.

[0042] The chamfered thread end 706 includes a first outer chamfered surface 708 and a second inner chamfered surface 709, wherein, in an axial plan view of the chamfered thread end 706, the first chamfered surface 708 is radially further away from the axis 707 than the second chamfered surface 709, as shown in the figure below. Figure 6a visible, Figure 6a A top view of the chamfered threaded end 706 of the screw 701 is shown. In other words, the first chamfered surface 708 at least partially surrounds the second chamfered surface 709. Thus, in the axial direction toward the chamfered threaded end 706, away from the axis, the chamfered threaded end 706 tapers from the outer diameter first with the first chamfered surface 708, and then tapers with the second chamfered surface 709 until it reaches the core diameter.

[0043] The first chamfered surface 708 extends with respect to the axial extension of the screw 701 (i.e., axis 707) at a first angle α, and the second chamfered surface 709 extends with respect to the axial extension of the screw 701 at a second angle β, wherein the second angle β is greater than the first angle α. The first angle α is ≥30° and ≤50°, and is currently 45°. The second angle β is ≥55° and ≤85°, and is currently 75°. Thus, the first chamfered surface 708 seamlessly transitions to the second chamfered surface 709, with a 30° "bend" between the linearly extending first chamfered surface 708 and the second chamfered surface 709.

[0044] Figure 5a It shows Figure 4 A partial sectional side view of the screw 701 being inserted into the spindle nut 702. Figure 5b It shows Figure 5aThe partial structure shows the last or initial possible contact point between the threads of the screw 701 and the threads of the spindle nut 702. In the axial direction, "behind" the chamfered thread end 706, the screw 701 includes a plurality of external threads 710, which begin at the chamfered thread end 706. The chamfered thread end 706, as the last or first thread 710, includes a first chamfered surface 708 and a second chamfered surface 709, and the plurality of external threads 710 extend helically away from the chamfered thread end 706. The spindle nut 702 includes a plurality of internal threads 711 corresponding to the external threads 710. Each of the internal threads 711 includes a thread flank having an angle consistent with or equal to the second angle β.

[0045] As mentioned, Figure 6a yes Figure 5a A top view of the chamfered thread end 706 of the screw 701, and Figure 6b Show Figure 5a A partial side view of the screw 701. (See image from...) Figure 6a As can be seen, the first chamfered surface 708 extends about 180° around the chamfered thread end 706, and the second chamfered surface 709 extends about 180° around the chamfered thread end 706. Although not shown, the chamfered thread end 706 may include a third chamfered surface that extends at a third angle relative to the axial extension of the screw 701, and the third angle is greater than the second angle β, wherein the second chamfered surface 709 is disposed between the first chamfered surface 708 and the third chamfered surface.

[0046] While the invention has been shown and described in detail in the accompanying drawings and the foregoing description, such illustrations and descriptions 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 implemented by those skilled in the art in practicing the claimed invention by studying the drawings, the disclosure, and the appended claims. In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite articles "a" or "an" do not exclude a plurality. The fact that only certain measures are recited in mutually different dependent claims does not mean that combinations of these measures cannot be used to achieve advantageous effects. Any reference numerals in the claims should not be construed as limiting the scope.

[0047] List of reference numerals: 1. Motor; 2. Connecting pin; 4. Energy storage spring; 5. First bearing / sleeve; 6. Second transmission gear; 8. Base support; 9. Absorber; 10. Damping arm; 11. Output shaft, main hub; 12. Drive rod, actuating rod; 13. Energy storage rod, spring charging rod; 14. Sleeve; 15. Second bearing; 101. First transmission gear; 111. Spline; 121. Third push arm; 122. Fourth push arm; 131. First push arm; 132. Second... Push arm; 301, First spring support; 302, Second spring support; 303, Connecting plate; 304, Guide rod; 601, Switching device; 602, Moving contact; 701, Screw; 702, Main shaft nut; 703, Protrusion; 704, Limiting rod; 705, Micro switch; 706, Chamfered thread end; 707, Axis; 708, First chamfered surface; 709, Second chamfered surface; 710, External thread; 711, Internal thread; α, First angle; β, Second angle.

Claims

1. An operating mechanism for a switching device (601), comprising: The motor (1), the axially extending screw (701), and the spindle nut (702) are, among which, The screw (701) is connected to the motor (1) and configured to be rotated by the motor (1). The spindle nut (702) is movably engaged with the screw (701), and the spindle nut (702) is configured to move linearly along the screw (701) as the screw (701) rotates. The screw (701) includes a chamfered threaded end (706) that can be inserted into the spindle nut (702), wherein the chamfered threaded end (706) includes a first chamfered surface (708) extending axially relative to the screw (701) at a first angle (α) and a second chamfered surface (709) extending axially relative to the screw (701) at a second angle (β), and the second angle (β) is greater than the first angle (α).

2. The operating mechanism according to the preceding claim, wherein, The first angle (α) is ≥30° and ≤50°, preferably 45°, and / or the second angle (β) is ≥55° and ≤85°, preferably 75°.

3. The operating mechanism according to any one of the preceding claims, wherein, In the axial direction toward the chamfered thread end (706), the chamfered thread end (706) first tapers with the first chamfered surface (708) and then tapers with the second chamfered surface (709).

4. The operating mechanism according to any one of the preceding claims, wherein, In the axial direction toward the end of the chamfered thread (706), the first chamfered surface (708) transitions seamlessly to the second chamfered surface (709).

5. The operating mechanism according to any one of the preceding claims, wherein, The first chamfered surface (708) and / or the second chamfered surface (709) extend in a linear or convex manner in the axial direction toward the end of the chamfered thread (706).

6. The operating mechanism according to any one of the preceding claims, wherein, The spindle nut (702) includes an internal thread (711) with a threaded flank, and the second angle (β) is deviated from, coincides with, is equal to or unequal to the angle of the threaded flank.

7. The operating mechanism according to any one of the preceding claims, wherein, The first chamfered surface (708) extends ≥180°, preferably ≥270° and / or <360° around the end of the chamfered thread (706), and / or the second chamfered surface (709) extends ≥180°, preferably ≥270° and / or <360° around the end of the chamfered thread (706).

8. The operating mechanism according to any one of the preceding claims, wherein, The last thread of the screw (701) includes the first chamfered surface (708) and the second chamfered surface (709).

9. The operating mechanism according to any one of the preceding claims, wherein, The chamfered thread end (706) includes a third chamfered surface that extends at a third angle relative to the axial extension of the screw (701), and the third angle is greater than the second angle (β).

10. The operating mechanism according to any one of the preceding claims, wherein, The screw (701) includes an external thread (710), the external thread (710) includes the chamfered thread end (706), and the spindle nut (702) includes an internal thread (711) corresponding to the external thread (710).

11. The operating mechanism according to any one of the preceding claims includes a rotatable output shaft (11) configured to perform an on / off operation of the switching device (601) by rotation, and is kinematically connected to the spindle nut (702).

12. A switching device (601) comprising a movable contact (602) and an operating mechanism according to any one of the preceding claims, wherein, The operating mechanism is configured to operate the movable contact (602) to perform the opening or closing operation of the switching device (601).

13. The switching device (601) according to the preceding claim, wherein, The switching device (601) is provided as a gas-insulated switching device, including a grounding switch with short-circuit capability, an isolating switch, an isolating and grounding switch, and / or a fast grounding switch.

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