Vacuum load tap changer
By introducing a ball bearing structure of bracket, timing loop and main board spacer into the vacuum on-load tap changer, the problems of poor timing loop support and high friction are solved, achieving higher reliability and smaller size, which is suitable for amorphous three-dimensional wound core transformers.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- DANDONG JINLI POWER EQUIP
- Filing Date
- 2025-06-19
- Publication Date
- 2026-07-07
AI Technical Summary
The timing loop of the vacuum on-load tap changer has poor support and high friction on the contact surface, resulting in high friction during rotation, which affects reliability and lifespan.
A vacuum on-load tap changer was designed, which adopts a bracket, timing ring and main board spacer structure. The upper surface of the timing ring forms a ball groove with balls inside that abut against the lower surface of the main board spacer, providing support and reducing friction. At the same time, the layout of the lever and vacuum tube is optimized to reduce space occupation and increase the number of switchable positions.
It improves the support effect of the timing loop, reduces friction, enhances reliability and lifespan, and reduces overall size and material cost, making it suitable for amorphous three-dimensional wound core transformers.
Smart Images
Figure CN224472399U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of electrical components, and in particular to a vacuum on-load tap changer. Background Technology
[0002] With the increasing demand for energy conservation, high efficiency, and intelligence in power systems, three-dimensional wound core transformers have become an important component of modern power distribution systems due to their advantages such as symmetrical three-phase magnetic circuits, low losses, low noise, and compact structure. These transformers optimize the magnetic circuit distribution through their three-dimensional winding structure, significantly improving operating efficiency and overload capacity.
[0003] In recent years, the application of amorphous alloy materials has further promoted the improvement of transformer performance. Amorphous three-dimensional wound core transformers combine the low-loss characteristics of amorphous alloys with the advantages of three-dimensional winding structures, possessing higher energy efficiency ratios and stronger short-circuit withstand capabilities, and are widely used in applications with strict power quality requirements.
[0004] In this type of transformer, the on-load tap changer is a key component responsible for adjusting the taps of the transformer windings during operation to adapt to grid voltage fluctuations and load changes. Vacuum on-load tap changers, due to their superior arc-extinguishing performance, low maintenance requirements, and high operational reliability, have gradually replaced traditional oil-immersed tap changers and become the mainstream choice.
[0005] The timing ring of a vacuum on-load tap changer drives a lever to rotate during operation, which in turn pulls the vacuum tube. A moving contact is fixed below the timing ring; this moving contact rotates with the timing ring and switches the connected output contact, thus switching the connection between the input and output contacts. To prevent the moving contact from pushing against the timing ring and causing deformation, a support structure is typically installed above the timing ring. However, fixed support structures often suffer from poor support effectiveness and high friction between the support structure and the timing ring. Utility Model Content
[0006] One objective of this invention is to solve the problems of poor timing loop support and high contact surface friction in vacuum on-load tap changers.
[0007] According to one aspect of this utility model, a vacuum on-load tap changer is provided, which includes a drive mechanism and a vacuum tube pull rod assembly. The vacuum tube pull rod assembly includes a bracket, a timing ring, and a mainboard spacer.
[0008] The support is ring-shaped and defines multiple circumferentially distributed and spaced-apart phase regions.
[0009] The timing loop is mounted on the support and configured to rotate relative to the support under the drive of the drive mechanism.
[0010] The motherboard spacer is positioned above the timing ring and fixed relative to the bracket.
[0011] The upper surface of the timing ring has multiple ball grooves, and each ball groove contains one ball; the ball abuts against the lower surface of the motherboard spacer.
[0012] Optionally, the lower surface of the motherboard spacer protrudes downward and forms a rib; multiple ball grooves face the rib so that the balls roll along the surface of the rib.
[0013] Optionally, the vacuum on-load tap changer also includes a tap assembly.
[0014] The tap changer assembly includes multiple input contacts, multiple sets of output contacts, multiple sets of connecting pieces, and multiple moving contacts.
[0015] Each set of output contacts includes multiple output contacts and is arranged circumferentially at the edge of the bracket, facing one phase region.
[0016] Each group of contacts consists of two contacts and is set within a phase region; the two contacts in each group are respectively connected to the input terminal contacts and are set to a corresponding set of output terminal contacts.
[0017] Multiple moving contacts are positioned below the timing loop and rotate synchronously with the timing loop; each moving contact is configured to change the connection state of two links in a set of links with the corresponding set of output terminal contacts during the rotation of the timing loop.
[0018] Optionally, the multiple ball grooves are divided into multiple groups, with each group of ball grooves corresponding to a moving contact.
[0019] The projection of each ball groove in each group onto the horizontal plane at least partially coincides with the projection of the corresponding moving contact onto the horizontal plane; or the angle between the projection of each ball groove in each group onto the horizontal plane and the projection of the corresponding moving contact onto the horizontal plane relative to the center of the timing loop is less than or equal to 5°.
[0020] Optionally, the moving contact includes a contact mounting plate and two contact plates.
[0021] The contact mounting plate is positioned below the timing loop.
[0022] Two contact pieces are arranged alternately on the contact mounting plate; one end of each contact piece overlaps with two connecting pieces, and the other end overlaps with two adjacent output terminal contact pieces or the same output terminal contact piece as the sequence ring rotates.
[0023] Optionally, the vacuum tube tie rod assembly may also include multiple sets of vacuum tubes.
[0024] Multiple sets of vacuum tubes are respectively set in a phase region; each set of vacuum tubes includes two vacuum tubes; each vacuum tube is connected to an input terminal contact and an output terminal contact of the corresponding phase region at both ends.
[0025] Optionally, the support has multiple insulated connecting arms extending radially from the inside to the outside to separate multiple phase regions within the support.
[0026] The vacuum tube tie rod assembly also includes multiple lever fixing shafts and multiple sets of levers.
[0027] Each lever fixing axis is arranged parallel to the axial direction of the timing ring and is located at the outer end of an insulated connecting arm.
[0028] Each set of levers is rotatably mounted on a lever fixed axis; each set of levers includes two levers, and the two levers in each set extend into an adjacent phase region and are connected to a vacuum tube; the levers are configured to rotate under drive during the rotation of the timing loop and drive the vacuum tube to move.
[0029] This utility model discloses a vacuum on-load tap changer, comprising a drive mechanism and a vacuum tube pull rod assembly. The vacuum tube pull rod assembly includes a bracket, a timing ring, and a mainboard spacer. The bracket is annular and defines multiple circumferentially distributed and spaced phase regions. The timing ring is mounted on the bracket and configured to rotate relative to the bracket under the drive mechanism. The mainboard spacer is positioned above the timing ring and fixed relative to the bracket. Multiple ball grooves are formed on the upper surface of the timing ring, with one ball in each groove; the balls abut against the lower surface of the mainboard spacer. By incorporating the balls, not only is a downward support force provided to the timing ring, but the frictional force during the timing ring's rotation is also reduced.
[0030] The above and other objects, advantages and features of this utility model will become more apparent to those skilled in the art from the following detailed description of some specific embodiments of this utility model in conjunction with the accompanying drawings. Attached Figure Description
[0031] The following sections will describe some specific embodiments of the present invention in a detailed manner by way of example and not limitation, with reference to the accompanying drawings. The same reference numerals in the drawings denote the same or similar parts or components. Those skilled in the art should understand that these drawings are not necessarily drawn to scale. In the drawings:
[0032] Figure 1 This is a schematic diagram of a vacuum on-load tap changer according to an embodiment of the present invention;
[0033] Figure 2 yes Figure 1 A schematic diagram of the vacuum tube pull rod assembly of the vacuum on-load tap changer is shown.
[0034] Figure 3 yes Figure 2 An exploded view of the vacuum tube tie rod assembly shown.
[0035] Figure 4 yes Figure 2 A partial planar schematic diagram of the vacuum tube tie rod assembly shown;
[0036] Figure 5 yes Figure 2 A partial schematic diagram of the vacuum tube tie rod assembly is shown.
[0037] Figure 6 yes Figure 2 A schematic cross-sectional view of the vacuum tube tie rod assembly shown;
[0038] Figure 7 yes Figure 6 A magnified view of part A in the middle;
[0039] Figure 8 This is a cross-sectional schematic diagram of a vacuum tube tie rod assembly according to another embodiment of the present invention;
[0040] Figure 9 yes Figure 8 A magnified view of part B in the middle section;
[0041] Figure 10 This is a cross-sectional schematic diagram of a vacuum tube tie rod assembly according to another embodiment of the present invention;
[0042] Figure 11 yes Figure 10 A magnified view of part C in the middle;
[0043] Figure 12 yes Figure 1 The diagram shows an exploded view of a vacuum on-load tap changer.
[0044] Figure 13 yes Figure 2 Another schematic diagram of the mainboard spacer of the vacuum tube tie rod assembly shown;
[0045] Figure 14 yes Figure 2 A schematic diagram of the timing loop of the vacuum tube tie rod assembly shown;
[0046] Figure 15 yes Figure 1 A schematic diagram of the drive mechanism of the vacuum on-load tap changer is shown.
[0047] Figure 16 yes Figure 15 A schematic diagram of the drive mechanism shown.
[0048] Figure 17 yes Figure 15A schematic diagram of the slotted component of the drive mechanism shown;
[0049] Figure 18 yes Figure 15 A cross-sectional schematic diagram of the drive mechanism shown. Detailed Implementation
[0050] In the description of this embodiment, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "axial", "radial", "circumferential", "clockwise", and "counterclockwise" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.
[0051] The terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first," "second," etc., may explicitly or implicitly include at least one of that feature, that is, include one or more of that feature.
[0052] In the description of this utility model, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified. When a feature "includes or contains" one or more of the features it covers, unless otherwise specifically described, this indicates that other features are not excluded and may be further included.
[0053] Unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," "fixing," and "coupling," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art should be able to understand the specific meaning of the above terms in this utility model according to the specific circumstances.
[0054] Furthermore, in the description of this utility model, the first feature being "above" or "below" the second feature may include the first and second features being in direct contact, or it may include the first and second features not being in direct contact but being in contact through another feature between them.
[0055] In other words, in the description of this utility model, "above," "on top of," and "over" the first feature and the second feature include the first feature being directly above or diagonally above the second feature, or simply indicating that the first feature is at a higher horizontal level than the second feature. "Below," "under," or "below" the second feature can mean the first feature is directly below or diagonally below the second feature, or simply indicating that the first feature is at a lower horizontal level than the second feature.
[0056] In the description of this utility model, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, device, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this utility model. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, devices, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.
[0057] Unless otherwise specified, all terms (including technical and scientific terms) used in the description of the embodiments of this utility model shall have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.
[0058] Figure 1 This is a schematic diagram of a vacuum on-load tap changer 10 according to an embodiment of the present invention; Figure 2 yes Figure 1 A schematic diagram of the vacuum tube pull rod assembly 30 of the vacuum on-load tap changer 10 shown. Figure 3 yes Figure 2 An exploded view of the vacuum tube tie rod assembly 30 shown; Figure 4 yes Figure 2 A partial planar schematic diagram of the vacuum tube tie rod assembly 30 is shown.
[0059] refer to Figures 1 to 4 As shown, this utility model provides a vacuum on-load tap changer 10, which includes a drive mechanism 20, a vacuum tube pull rod assembly 30, and a tap changer assembly. The vacuum tube pull rod assembly 30 includes a bracket 31, multiple sets of vacuum tubes 32, a timing ring 33, multiple lever fixing shafts 35, and multiple levers 34.
[0060] The support 31 is annular and has multiple radially extending insulating connecting arms 313 to divide multiple phase regions 31A within the support 31. Each group of vacuum tubes 32 is disposed within a phase region 31A, and each group of vacuum tubes 32 includes two vacuum tubes 32. A timing ring 33 is disposed on the support 31 and configured to rotate relative to the support 31 under the drive of the drive mechanism 20. Each lever fixing shaft 35 is arranged parallel to the axial direction of the timing ring 33 and is disposed at the outer end of an insulating connecting arm 313. Each group of levers 34 is rotatably disposed on a lever fixing shaft 35. Each group of levers 34 includes two levers 34, and the two levers 34 in each group extend into an adjacent phase region 31A and are connected to a vacuum tube 32. The levers 34 are configured to rotate under drive during the rotation of the timing ring 33 and drive the vacuum tubes 32 to move.
[0061] The tap changer assembly includes multiple input contacts 41 and multiple sets of output contacts 42. The input contacts 41 and output contacts 42 are fixedly disposed relative to the bracket 31. Each set of output contacts 42 includes multiple output contacts 42, and each input contact 41 is configured to switch the connected output contact 42 as the timing loop 33 rotates.
[0062] The vacuum on-load tap changer 10 is used to adjust the winding turns ratio of a transformer under uninterrupted load current conditions. (Reference) Figure 4 As shown, the vacuum on-load tap changer 10 in this embodiment defines three phase regions 31A to match the three phases of a three-phase transformer. It can be understood that when applied to scenarios other than three-phase transformers, the vacuum on-load tap changer 10 can also be designed to define two, four or more phase regions 31A.
[0063] The bracket 31 of the vacuum on-load tap changer 10 in this embodiment includes an annular outer ring portion 311, a central shaft portion 312 located at the center of the outer ring portion 311, and an insulating connecting arm 313 extending radially from the inside to the outside to connect the central shaft portion 312 and the outer ring portion 311. In this embodiment, there are three insulating connecting arms 313, which divide the internal space of the bracket 31 into three equal phase regions 31A at 120° intervals. The bracket 31 is entirely made of insulating material, and the insulating connecting arms 313 have a certain thickness, thereby electrically isolating adjacent phase regions 31A.
[0064] Existing vacuum on-load tap changers 10 mainly include two forms: a strip-shaped structure, where the three phases are arranged sequentially along a straight line, and the overall switch is in the shape of a strip box; and a column-shaped structure, where the three phases are arranged sequentially along an axial direction, and the overall switch is in the shape of a cylinder. The vacuum on-load tap changer 10 of this embodiment is disc-shaped, therefore its cross-sectional area is smaller than that of the strip-shaped structure. Furthermore, because the three phase regions 31A are distributed on the same horizontal plane, its radial height is smaller than that of the column-shaped structure, thus effectively reducing the overall size compared to existing vacuum on-load tap changers 10. In addition, the vacuum on-load tap changer 10 of this embodiment is positioned so that the three phases and the corresponding output contact 42 are aligned with the three sets of high and low voltage coils of the amorphous three-dimensional wound core transformer. This allows for convenient wiring while minimizing the height of the enclosure, thereby saving on enclosure material costs and transformer oil usage, which is beneficial for the miniaturization and greening of transformers.
[0065] Vacuum on-load tap changers 10 are available in two types: single-vacuum-tube 32 and double-vacuum-tube 32. The double-vacuum-tube 32 type offers advantages such as long electrical life, short switching time, strong arc-extinguishing capability, and high reliability, making it suitable for long-life or high-frequency operation scenarios. However, because the double-vacuum-tube 32 type has a larger number of vacuum tubes 32, its structure is correspondingly more complex, resulting in a larger size and greater space occupation when installed in amorphous three-dimensional wound core transformers. Therefore, to further reduce the size of the vacuum on-load tap changer 10, this invention creatively improves the internal structure of the vacuum tube pull rod assembly 30 used to pull the vacuum tubes 32, making its structure more compact.
[0066] Figure 5 yes Figure 2 A partial schematic diagram of the vacuum tube tie rod assembly 30 is shown.
[0067] refer to Figures 3 to 5 As shown, in this embodiment, levers 34 used to pull the vacuum tube 32 are arranged in pairs, and a lever fixing shaft 35 is provided at the outer end of each insulating connecting arm 313. Each pair of levers 34 is rotatably mounted on a lever fixing shaft 35, and the two levers 34 in each pair extend into an adjacent phase region 31A and are connected to a vacuum tube 32. Since the lever fixing shaft 35 is arranged parallel to the axial direction of the timing ring 33, the levers 34 can pull the vacuum tube 32 during rotation to drive the vacuum tube 32 to move. The movement of the vacuum tube 32 includes being pulled outward to cut off the circuit, and being reset and closed under the action of external forces such as springs.
[0068] In the traditional design, the vacuum on-load tap changer 10 requires a separate lever fixing shaft 35 for each lever 34 that pulls the vacuum tube 32, and both the lever 34 and the lever fixing shaft 35 are located inside the phase region 31A. This not only leads to a shortage of space inside the phase region 31A, but also interferes with the arrangement of other parts, including the output terminal contact 42, which in turn reduces the number of output terminal contact 42 sets and the number of switchable positions of the vacuum on-load tap changer 10.
[0069] The vacuum tube pull rod assembly 30 of the vacuum on-load tap changer 10 in this embodiment, while not weakening the electrical insulation effect of the insulating connecting arm 313 on the vacuum tubes 32 in the two phase regions 31A, creatively utilizes the space at the outer end of the insulating connecting wall, i.e., near the outer ring 311 of the bracket 31, so that the two levers 34 in each group are coaxially arranged and extend into the two adjacent different phase regions 31A. This breaks the technical prejudice in the art that the interphase insulation area cannot be utilized and that the levers 34 and lever fixing shaft 35 need to be set in the phase region 31A, providing a completely new internal component layout method for the vacuum on-load tap changer 10. While making the structure of the vacuum on-load tap changer 10 more compact, it also avoids the setting position of the levers 34 and lever fixing shaft 35 from interfering with the arrangement of other components, including the output terminal contact 42. This allows each phase region 31A of the vacuum on-load tap changer 10 to be equipped with more output terminal contacts 42 at the same time, and provides more switchable positions.
[0070] In some alternative embodiments, the bracket 31 is integrally molded from an insulating material. Furthermore, the lever 34 and the lever fixing shaft 35 are also made of an insulating material, such as ceramic.
[0071] refer to Figure 3 As shown, the bracket 31 may further include a fixing post 314 extending upward from the outer ring portion 311 at the outer end of the insulating connecting arm 313. The upper and lower ends of each lever fixing shaft 35 are fixed to the fixing post 314 and the inner side of the outer ring portion 311. The insulating connecting arm 313 may be recessed at its outer end position and together with the outer ring portion 311 define a notch communicating with two adjacent phase regions 31A. Each set of levers 34 may be disposed at the notch to extend to the two adjacent phase regions 31A respectively.
[0072] In some alternative embodiments, the two vacuum tubes 32 in each group are respectively disposed near the insulating connecting arm 313 on the side of their respective phase region 31A; and the vacuum tube 32 includes a fixed end 321 and a moving end 322. The fixed end 321 is near the inner side of the support 31 and is fixed relative to the support 31; the moving end 322 is near the outer side of the support 31 and is connected to a lever 34 so that it is pulled outward relative to the fixed end 321 by the action of the lever 34 and the vacuum tube 32 is disconnected.
[0073] refer to Figure 4 and Figure 5 As shown, in this embodiment, each vacuum tube 32 is positioned close to the insulating connecting arm 313 of the support 31, and can be further positioned parallel to the extending direction of the insulating connecting arm 313. The fixed end 321 of the vacuum tube 32 is close to the inner side of the support 31 and fixed relative to the support 31, while the moving end 322 is close to the outer side of the support 31 so as to connect with the lever 34 and be pulled outward. The vacuum tube 32 in this embodiment is also called a vacuum interrupter. The structure and working principle of the vacuum tube 32 itself are well known to those skilled in the art, and therefore will not be described in detail.
[0074] refer to Figure 5 As shown, in some optional embodiments, the end of the lever 34 connecting to the vacuum tube 32 has a groove 34A with an opening perpendicular to the lever's fixed axis 35; the vacuum tube 32 also includes a pull rod 323. The pull rod 323 is fixed to the moving end 322 and is used to connect the moving end 322 to the lever 34; the end of the pull rod 323 connecting to the lever 34 has a ball head that engages in the groove 34A and slides along the groove 34A when the lever 34 pulls the moving end 322.
[0075] Since the movement trajectory of lever 34 during rotation is an arc, if lever 34 is not movably fixed to the moving end 322 of vacuum tube 32, lever 34 will not only pull the moving end 322 of vacuum tube 32 outward during rotation, but will also cause vacuum tube 32 to shift laterally in the pulling direction. This will increase the wear of vacuum tube 32 and reduce its service life. To overcome this problem, this embodiment indirectly connects the moving end 322 to lever 34 via pull rod 323, and a groove 34A with an opening perpendicular to the lever fixing axis 35 is opened at the end of lever 34 connecting pull rod 323. This allows pull rod 323 to slide within the groove 34A when lever 34 pulls the moving end 322 of vacuum tube 32, ensuring that the moving end 322 of vacuum tube 32 is only pulled and does not shift.
[0076] refer to Figure 5 As shown, in some optional embodiments, the timing ring 33 has radially protruding toothed structures formed on its periphery. The lever 34 includes a lever body 341 and a roller shaft 342. One end of the lever body 341 extends into a phase region 31A and is connected to a vacuum tube 32, and the other end of the lever 34 has an axially formed mounting hole; the roller shaft 342 is rotatably disposed in the mounting hole relative to the lever body 341 and extends to abut against the toothed structure so that it is pushed by the toothed structure and drives the lever 34 to rotate during the rotation of the timing ring 33.
[0077] First, it should be noted that the axial direction mentioned in any embodiment of this utility model refers to the direction of the rotation axis of the timing ring 33. That is to say, in this embodiment, the direction of the mounting hole on the lever 34 is the same as the straight line of the rotation axis of the timing ring 33. In this embodiment, the lever 34 is not integrally formed but is set as two parts: the lever body 341 and the roller shaft 342. This is to enable the roller shaft 342 to rotate relative to the lever body 341, thereby reducing the wear of the roller shaft 342, which abuts against the toothed structure of the timing ring 33 and slides on the surface of the toothed structure.
[0078] In some alternative embodiments, lever 34 also includes a bushing (not shown). The bushing is disposed within a mounting hole to space the roller shaft 342 from the lever body 341. The bushing serves to further reduce wear on the roller shaft 342 as it rotates relative to the lever body 341.
[0079] Figure 6 yes Figure 2 A schematic cross-sectional view of the vacuum tube tie rod assembly 30 shown; Figure 7 yes Figure 6 A magnified view of part A in the middle; Figure 8 This is a cross-sectional schematic diagram of a vacuum tube tie rod assembly 30 according to another embodiment of the present invention; Figure 9 yes Figure 8 A magnified view of part B in the middle section; Figure 10 This is a cross-sectional schematic diagram of a vacuum tube tie rod assembly 30 according to another embodiment of the present invention; Figure 11 yes Figure 10 A magnified view of part C in the middle.
[0080] The toothed structure on the timing ring 33 can periodically drive the lever 34 to rotate and pull the vacuum tube 32, thereby causing the vacuum tube 32 to periodically disconnect. By reasonably setting the shape of the lever 34, the rotation of all levers 34 can be controlled by the same timing ring 33.
[0081] Figure 6 , Figure 8 and Figure 10 The toothed structure of the timing ring 33 in one embodiment is illustrated. It can be seen that the toothed structure of the timing ring 33 can protrude radially outward and make the roller shaft 342 abut against the radially outer side of the toothed structure; it can also protrude radially and make the roller shaft 342 abut against the radially inner side of the toothed structure; or it can protrude radially inward and outward at the same time and define a track with a constant width, so that the roller shaft 342 abuts against the radially inner and outer sides of the track at the same time.
[0082] In some alternative embodiments, the tooth-like structure comprises a plurality of circumferentially spaced tooth base surfaces 331, a tooth tip surface 332 located between two adjacent tooth base surfaces 331, and a C2 continuous curved surface 333 connecting adjacent tooth base surfaces 331 and tooth tip surfaces 332; wherein each tooth tip surface 332 and its two adjacent C2 continuous curved surfaces 333 together define a boss protruding from the tooth base surface 331 and used to drive the lever 34 to rotate during the rotation of the timing ring 33.
[0083] refer to Figure 7 As shown, during the rotation of the timing loop 33, when the roller shaft 342 slides against the tooth bottom surface 331, the vacuum tube 32 is in a closed state. When the roller shaft 342 is pushed by the C2 continuous curved surface 333 and slides to the tooth top surface 332, the lever 34 rotates accordingly and pulls the vacuum tube 32 to open. When the roller shaft 342 slides back to the tooth bottom surface 331 along the C2 continuous curved surface 333, the vacuum tube 32 resets and closes again. In this embodiment, the tooth bottom surface 331 and the tooth top surface 332 are connected by the C2 continuous curved surface 333, which is a C2 continuous curve located on a horizontal plane stretched radially to form a curved surface. Due to the characteristics of the C2 continuous curve, the sliding acceleration of the roller shaft 342 on the tooth structure surface in this embodiment is 0. Therefore, the lever 34 slides more smoothly on the tooth structure surface in this embodiment, and the bouncing of the vacuum tube 32 caused by the rotational inertia of the lever 34 can be eliminated.
[0084] Figure 12 yes Figure 1 An exploded view of the vacuum on-load tap changer 10 shown. Figure 13 yes Figure 2 Another schematic diagram of the main board spacer 36 of the vacuum tube pull rod assembly 30 shown in the figure illustrates the bottom surface of the main board spacer 36.
[0085] In addition to the improvements to the internal component layout of the vacuum on-load tap changer 10, i.e., the vacuum tube pull rod assembly 30, in the above embodiments, this utility model also improves other structures of the vacuum on-load tap changer 10.
[0086] In some alternative implementations, the tap assembly includes, in addition to the input contact 41 and the output contact 42, multiple sets of connecting pieces 43 and multiple moving contacts 44.
[0087] The output contact 42 is arranged circumferentially along the edge of the bracket 31 and extends to the outside of the bracket 31; the tap assembly also includes multiple sets of connecting pieces 43 and multiple moving contacts 44.
[0088] Each set of output contacts 42 includes multiple output contacts 42 and is circumferentially disposed at the edge of the bracket 31, facing a phase region 31A. Each set of connectors 43 includes two connectors 43 and is disposed within a phase region 31A; the two connectors 43 in each set are respectively connected to the input contacts 41 and are disposed corresponding to a set of output contacts 42. Multiple moving contacts 44 are disposed below the timing ring 33 and rotate synchronously with the timing ring 33; each moving contact 44 is configured to change the connection state between two connectors 43 in a set of connectors 43 and the corresponding set of output contacts 42 during the rotation of the timing ring 33.
[0089] refer to Figure 12 As shown, the output contact 42 can be directly or indirectly fixed to the outer ring 311 of the bracket 31 and partially extend to the outside of the bracket 31 for wiring convenience. A partition can be provided between the output contact 42 and the bracket 31 to separate them, and the partition can also be used to support and fix the connecting piece 43. The two connecting pieces 43 in each phase region 31A are spaced apart, and each of the two connecting pieces 43 is connected to the input contact 41 via a vacuum tube 32 in the phase region 31A. At the same time, the connected output contact 42 is changed by a movable contact 44. The movable contact 44 is fixed on the timing ring 33 so that it rotates with the timing ring 33 during rotation and switches the output contact 42 connected to the connecting piece 43, thereby changing the output contact 42 connected to the input contact 41.
[0090] In some alternative implementations, the moving contact 44 includes a contact mounting plate and two contact plates.
[0091] The contact mounting plate is positioned below the timing ring 33. Two contact pieces are positioned alternately on the contact mounting plate; one end of each contact piece overlaps with one of the two connecting pieces 43, and the other end overlaps with two adjacent output terminal contact pieces 42, or overlaps with the same output terminal contact piece 42, as the timing ring 33 rotates.
[0092] The timing of the timing loop 33 driving the lever 34 to rotate and pull the vacuum tube 32 is designed to correspond to the timing of the switching of the two contact pieces on the moving contact 44 to the output terminal contact 42, so that the vacuum on-load tap changer 10 can switch positions under on-load conditions. The timing of the operation of the vacuum tube 32 and the moving contact 44 when the vacuum on-load tap changer 10 switches positions is known to those skilled in the art and will not be described in detail here.
[0093] In order for the moving contact 44 to reliably engage with the connecting piece 43 and the output contact 42, the timing ring 33 needs to provide sufficient downward pressure to the moving contact 44. Conversely, the moving contact 44 will also push upward against the timing ring 33. To prevent deformation of the timing ring 33, in some alternative embodiments, refer to... Figure 3As shown, the vacuum tube pull rod assembly 30 in this embodiment also includes a motherboard spacer 36. The motherboard spacer 36 is disposed above the timing ring 33 and fixedly disposed relative to the bracket 31, thereby clamping the timing ring 33 between the two together with the bracket 31, so that the timing ring 33 can rotate relative to the bracket 31 and the motherboard spacer 36 but cannot move up and down.
[0094] In this embodiment, the upper surface of the timing ring 33 has multiple ball grooves, and each ball groove contains a ball 37. The ball 37 abuts against the lower surface of the motherboard spacer 36. The ball 37 can roll both within the ball groove and relative to the lower surface of the motherboard spacer 36. By providing the ball 37, not only can a downward supporting force be provided to the timing ring 33 to counteract the upward thrust of the moving contact 44, but the frictional force during the rotation of the timing ring 33 can also be reduced.
[0095] refer to Figure 13 As shown, in some alternative embodiments, the lower surface of the motherboard spacer 36 protrudes downward to form a rib 361; a plurality of ball grooves face the rib 361 to allow the balls 37 to roll along the surface of the rib 361. The formation of the rib 361 can locally increase the thickness and strength of the motherboard spacer 36.
[0096] Figure 14 yes Figure 2 The diagram shows a timing loop 33 of the vacuum tube tie rod assembly 30, with the top surface of the timing loop 33 shown.
[0097] Figure 14 The dotted line indicates the projected position of the moving contact 44 on the horizontal plane. (Reference) Figure 14 As shown, in some optional embodiments, the multiple ball grooves are divided into multiple groups, and each group of ball grooves corresponds to a moving contact 44. The projection of each ball groove in each group onto the horizontal plane at least partially coincides with the projection of the corresponding moving contact 44 onto the horizontal plane; or the angle between the projection of each ball groove in each group onto the horizontal plane and the projection of the corresponding moving contact 44 onto the horizontal plane relative to the center of the timing loop 33 is less than or equal to 5°.
[0098] Figure 14 The diagram illustrates the placement of the ball bearing 37, and it can be understood that the position of the ball bearing groove coincides with the placement of the ball bearing 37. In this embodiment, each group of ball bearing grooves may include two ball bearing grooves, and they are disposed on opposite sides of the projection of the moving contact 44 onto the horizontal plane. The projection of each ball bearing groove in each group onto the horizontal plane may at least partially coincide with the projection of the corresponding moving contact 44 onto the horizontal plane, that is, the ball bearing groove is located directly above the moving contact 44. The projection of each ball bearing groove in each group onto the horizontal plane and the projection of the corresponding moving contact 44 onto the horizontal plane may also have an angle of less than or equal to 5° relative to the center of the timing loop 33, that is, the ball bearing groove is disposed close to the moving contact 44.
[0099] Figure 15 yes Figure 1 A schematic diagram of the drive mechanism 20 of the vacuum on-load tap changer 10 shown. Figure 16 yes Figure 15 A schematic diagram of the slotted fan 22 of the drive mechanism 20 shown; Figure 17 yes Figure 15 A schematic diagram of the slotted part 23 of the drive mechanism 20 shown; Figure 18 yes Figure 15 A cross-sectional schematic diagram of the drive mechanism 20 shown.
[0100] This invention also improves the drive mechanism 20. (See reference) Figures 15 to 18 As shown, the drive mechanism 20 in this embodiment includes a drive motor 21, a slotted fan 22, a slotted component 23, and a transmission shaft 24.
[0101] refer to Figure 16 As shown, the slotted fan 22 has a first slotted wheel 221 and a second slotted wheel 222 distributed along the axial direction; wherein the first slotted wheel 221 includes a plurality of first slotted teeth spaced apart along the edge of the slotted fan 22, and two adjacent first slotted teeth define a slot 22A; the second slotted wheel 222 includes a plurality of second slotted teeth spaced apart along the edge of the slotted fan 22, and two adjacent second slotted teeth define a locking groove 22B; each slot 22B is directly opposite a second slotted tooth. A drive motor is used to drive the slotted member to rotate.
[0102] refer to Figure 17 As shown, the grooving member 23 has a column portion 231 and a locking pin 232; wherein the locking pin 232 is located on the side of the column portion 231 and is provided corresponding to the first grooved wheel 221, and an avoidance groove 23A is formed on the column portion 231 on the same side as the locking pin 232, and the avoidance groove 23A is provided corresponding to the second grooved wheel 222.
[0103] Figure 18 The diagram not only illustrates the state of the slotted component 23 when the locking pin 232 is inserted into a slot 22A, but also uses dashed lines to indicate the state of the slotted component 23 when the locking pin 232 is not inserted into a slot 22A. (Reference) Figure 18As shown, during rotation, the locking pin 232 periodically extends into a slot 22A. Driven by the locking pin 232, the slotted fan 22 is pushed and rotates relative to the locking member 23. At this time, the clearance slot 23A is directly opposite a second tooth, which can pass through the clearance slot 23A and move from one side of the column portion 231 to the other side, thereby allowing the column portion 231 to move from one locking slot 22B to another adjacent locking slot 22B. When the locking pin 232 is not inserted into the slot 22A, because the clearance slot 23A is not directly opposite any second tooth, the two second teeth located on both sides of the column portion 231 can lock the column portion 231 in the locking slot 22B formed between them, thus allowing the locking member 23 to rotate only relative to the slotted fan 22 without moving.
[0104] The slotted fan 22 and the slotted component 23 together constitute a Geneva mechanism, which has the function of converting continuous rotation into unidirectional periodic rotation with pauses. Existing Geneva mechanisms all design the slotted fan 22 as a disc, with slots 22A and locking slots 22B spaced in a single layer along the periphery of the circular slotted fan 22. Therefore, given a fixed number of slots 22A formed on the surface of the slotted fan 22, existing Geneva mechanisms require a slotted fan 22 with a larger surface area. This embodiment overcomes the technical bias of the prior art requiring the slotted fan 22 to have slots 22A and locking slots 22B arranged on the same layer. It creatively proposes a technical solution of setting slots 22A and locking slots 22B in a double layer on the slotted fan 22. This allows for a more compact arrangement of slots 22A given a fixed number of slots 22A formed on the surface of the slotted fan 22, greatly reducing the distribution angle of the slots 22A, thereby reducing the surface area of the slotted fan 22 and allowing the drive mechanism 20 to be designed to be smaller.
[0105] Furthermore, in this embodiment, the drive shaft 24 connects the slotted fan 22 and the timing ring 33 so that the slotted fan 22 and the timing ring 33 rotate coaxially.
[0106] In a vacuum on-load tap changer 10 with three phase regions 31A, the angle between each phase region 31A and the axis of the timing ring 33 is 120°. This means that the timing ring 33 only needs to rotate a maximum of 120° to complete the switching between the lowest and highest gear positions. However, the existing slotted wheel mechanism 20 used in the vacuum on-load tap changer 10 cannot compress the distribution angle of the slots 22A and 22B to within 120° when the slots 22A and 22B are arranged in a single layer. In fact, the number of slots 22A formed on the slot fan 22 is less than the number of gear positions of the vacuum on-load tap changer 10. This means that the slot fan 22 may need to rotate more than one revolution to complete the switching between the lowest and highest gear positions. In this case, the existing vacuum on-load tap changer 10 generally needs to be equipped with a gear transmission mechanism consisting of two or more gears to change the transmission ratio between the slot fan 22 and the timing ring 33. The setting of the gear transmission mechanism not only increases the production cost of the vacuum on-load tap changer 10, but also inevitably increases the size of the drive mechanism 20.
[0107] The vacuum on-load tap changer 10 of this embodiment can completely overcome the above-mentioned problems: the drive mechanism 20 sets up a double layer of tap 22A and locking slot 22B on the tap spool 22, so even if there are up to 9 taps 22A formed on the tap spool 22, the distribution angle of the taps 22A can be as follows. Figure 16 The angle is compressed to within 120°, so that the slotted fan 22 can be designed to be directly connected to the timing ring 33 via the drive shaft 24 and rotate synchronously on the same axis, without the need to set up a gear transmission mechanism to change the transmission ratio between the slotted fan 22 and the timing ring 33.
[0108] Based on this, in some optional embodiments, the slotted fan 22 can also be as follows: Figure 16 The design shown is fan-shaped, with the first and second slots distributed on the arc-shaped edge of the slotted fan 22.
[0109] In this embodiment, on the first groove wheel of the slotted fan 22, the included angle between the two slots 22A at both ends and the rotation axis of the slotted fan 22 corresponds to the rotation angle required for the timing ring 33 to rotate from the lowest gear to the highest gear. Therefore, the included angle between the two slots 22A at both ends and the rotation axis of the slotted fan 22 is less than or equal to 120°.
[0110] The slot 22A is defined by first teeth distributed on the arc-shaped edge of the slot fan 22. Therefore, the angle between the two ends of the arc-shaped edge of the slot fan 22 and its own rotation axis is greater than the angle between the two slots 22A at both ends and the rotation axis of the slot fan 22, and may be greater than 120°. (See also...) Figure 16It is understood that the fan-shaped groove fan 22 described in this embodiment refers to the surface of the groove fan 22 being fan-shaped, rather than limiting the cross-sectional shape of the groove fan 22 to conform to the fan shape obtained by cutting a part from a circle.
[0111] The angle between the two slots 22A at both ends and the rotation axis of the slot fan 22 refers to the angle between the bottom end of each slot 22A and the rotation axis of the slot fan 22.
[0112] In some alternative embodiments, at at least one end of the arcuate edge of the slotted fan 22, the second grooved wheel further defines a semi-locking groove 22C; the semi-locking groove 22C has a second groove tooth on only one side, so as to release the slotted member 23 from locking with the slotted fan 22 after the column portion 231 enters the semi-locking groove 22C.
[0113] refer to Figure 16 and Figure 18 As shown, the semi-locking groove 22C located at one end of the arc-shaped edge of the tapping fan 22 has a second tooth on only one side, and therefore does not have the function of locking the tapping member 23 of the locking groove 22B. After the column part 231 enters the semi-locking groove 22C, the tapping member 23 is released from locking with the tapping fan 22, thereby facilitating the disassembly and maintenance of the vacuum on-load tap changer 10.
[0114] For the vacuum on-load tap changer 10 with core-pulling function, the above operation allows the rotating moving parts inside the machine to rotate to the positions between each phase, thereby avoiding interference with stationary parts and enabling the moving parts to be pulled out smoothly. This design facilitates on-site maintenance or replacement operations without having to return the entire transformer to the factory for disassembly, significantly improving maintenance efficiency and economy.
[0115] In some alternative embodiments, the drive mechanism 20 further includes an anti-detachment component (not shown). The anti-detachment component is detachably disposed at one end of the dial fan 22 where a semi-locking groove 22C is formed, for preventing the column portion 231 from entering the semi-locking groove 22C.
[0116] The anti-detachment component can be a detachable part such as a bolt. By setting the anti-detachment component to prevent the column part 231 from entering the semi-locking groove 22C, the accidental release of the locking component 23 from the locking fan 22 due to misoperation can be avoided.
[0117] In some alternative implementations, refer to Figure 17 As shown, the locking pin 232 is cylindrical and is rotatably disposed relative to the column portion 231.
[0118] The cylindrical locking pin 232, which is rotatably mounted, can reduce the wear of the slot fan 22 and the slotting component 23, and facilitates its automatic alignment and insertion into the slot 22A during the rotation of the slot fan 22, thereby extending the service life of the drive mechanism 20.
[0119] In some alternative embodiments, the vacuum on-load tap changer 10 also includes a main board 38. The main board 38 is disposed above the main board spacer 36 and fixed relative to the bracket 31; and the drive mechanism 20 is fixed to the main board 38.
[0120] The motherboard 38 and the motherboard spacer 36 can be made of different materials. The motherboard 38 can be made of a material that is easy to shape and the upper surface can be formed with openings and a fixed structure of a specific shape to facilitate the fixing of the drive mechanism 20. The motherboard spacer 36 can be made of ceramic material to reduce the friction between it and the ball 37.
[0121] In addition to the components mentioned in the above embodiments, the vacuum on-load tap changer 10 is typically equipped with a transition resistor (not shown in the figure) to limit the circulating current. To facilitate the installation of the components, in some alternative embodiments, the vacuum tube pull rod assembly 30 may further include a lower cover 39 disposed below the bracket 31 and removable relative to the bracket 31 to cover the lower side of each phase region 31A.
[0122] It should be noted that, in the above embodiments of this utility model, the vacuum tube pull rod assembly 30 can be used independently and is not limited to use in the vacuum on-load tap changer 10. For example, the vacuum tube pull rod assembly 30 can be applied to other electrical equipment 10 equipped with vacuum tubes 32, such as vacuum circuit breakers and vacuum contactors. In other words, the electrical equipment 10 using the vacuum tube pull rod assembly 30 in this utility model includes, but is not limited to, the vacuum on-load tap changer 10.
[0123] Therefore, those skilled in the art should recognize that although many exemplary embodiments of the present invention have been shown and described in detail herein, many other variations or modifications conforming to the principles of the present invention can be directly determined or derived from the disclosure of the present invention without departing from the spirit and scope of the present invention. Therefore, the scope of the present invention should be understood and recognized as covering all such other variations or modifications.
Claims
1. A vacuum on-load tap changer, characterized in that... Includes the drive mechanism and vacuum tube tie rod assembly; in The vacuum tube tie rod assembly includes: The support is ring-shaped and defines a plurality of circumferentially distributed and spaced-apart phase regions; A timing loop, disposed on the support and configured to rotate relative to the support under the drive of the drive mechanism; and The motherboard spacer is positioned above the timing ring and fixedly mounted relative to the bracket; and The upper surface of the timing ring has multiple ball grooves, and each ball groove contains a ball; the ball abuts against the lower surface of the motherboard spacer.
2. The vacuum on-load tap changer according to claim 1, characterized in that... The lower surface of the motherboard partition protrudes downward to form a rib; the plurality of ball grooves face the rib so that the balls roll along the surface of the rib.
3. The vacuum on-load tap changer according to claim 1, characterized in that... It also includes tap-out components; The tap assembly includes: Multiple input contacts and multiple sets of output contacts, each set of output contacts including multiple output contacts, and arranged circumferentially at the edge of the bracket, facing one of the phase regions; Multiple sets of interconnects, each set comprising two interconnects disposed within one phase region; the two interconnects in each set are respectively connected to the input terminal contact and are configured corresponding to a set of output terminal contacts; and Multiple moving contacts are disposed below the timing ring and rotate synchronously with the timing ring; each moving contact is configured to change the connection state of two of the connecting pieces in a set of connecting pieces and the corresponding set of output terminal contacts during the rotation of the timing ring.
4. The vacuum on-load tap changer according to claim 3, characterized in that... The plurality of ball grooves are divided into multiple groups, and each group of ball grooves corresponds to one moving contact; and The projection of each ball groove in each group onto the horizontal plane at least partially coincides with the projection of the corresponding moving contact onto the horizontal plane; or the angle between the projection of each ball groove in each group onto the horizontal plane and the projection of the corresponding moving contact onto the horizontal plane relative to the center of the timing loop is less than or equal to 5°.
5. The vacuum on-load tap changer according to claim 3, characterized in that... The moving contact includes: A contact mounting plate is disposed below the timing loop; Two contact pieces are disposed at intervals on the contact mounting plate; one end of each of the two contact pieces is respectively attached to the two connecting pieces, and the other end is respectively attached to two adjacent output terminal contact pieces or to the same output terminal contact piece as the timing loop rotates.
6. The vacuum on-load tap changer according to claim 3, characterized in that... The vacuum tube tie rod assembly also includes: Multiple sets of vacuum tubes are respectively arranged in one phase region; each set of vacuum tubes includes two vacuum tubes; each vacuum tube is connected at both ends to the input terminal contact and the output terminal contact of the corresponding phase region.
7. The vacuum on-load tap changer according to claim 6, characterized in that... The bracket has a plurality of insulated connecting arms extending radially from the inside to the outside to separate a plurality of the phase regions within the bracket; The vacuum tube tie rod assembly also includes: Multiple lever fixing shafts, each of which is arranged parallel to the axial direction of the timing ring and is located at the outer end of one of the insulating connecting arms; as well as Multiple sets of levers, each set of levers being rotatably mounted on a lever fixed axis; each set of levers includes two levers, and the two levers in each set extend into an adjacent phase region and are connected to a vacuum tube; the levers are configured to rotate under drive and drive the vacuum tube to move during the rotation of the timing loop.