Tap selector moving contact drive mechanism

The movable contact drive mechanism in tap selectors addresses durability and part count issues by rotating in contact or non-contact states, reducing load torque and wear, and using identical parts for both tap sides, enhancing reliability and cost-effectiveness.

JP7785656B2Active Publication Date: 2025-12-15KK TOSHIBA
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Patent Information

Application Number
JP2022189947
Authority / Receiving Office
JP · JP
Patent Type
Patents
Current Assignee / Owner
Filing Date
2022-11-29
Publication Date
2025-12-15
Estimated Expiration
2042-11-29

AI Technical Summary

Technical Problem

Existing tap selectors in on-load tap changers face issues with durability due to high load during switching and require additional parts, increasing space and costs.

Method used

A movable contact drive mechanism featuring a movable contact assembly with a drive slider, lift arm, and movable contact that rotates circumferentially, maintaining contact or non-contact states based on rotation, reducing load and part count.

Benefits of technology

The mechanism reduces load torque during switching, enhances durability, and prevents wear, while using identical parts for both odd and even tap sides, thus lowering costs and improving assembly ease.

✦ Generated by Eureka AI based on patent content.

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Patent Text Reader

Abstract

To provide a movable contact drive mechanism of a tap selector, capable of suppressing an increase of the number of components while suppressing a load at a switching and having an excellent durability.SOLUTION: A movable contact drive mechanism of a tap selector of an embodiment, has a movable contact assembly. The movable contact assemble rotates a circumference of a reference shaft to a peripheral direction. The movable contact assembly comprises: a driving slider; an elevating arm; and a movable contact. The driving slider slits to a radial direction which is orthogonal to the shaft direction along the reference shaft. The elevating arm rotates in cooperation with a slit operation of the driving slider. The movable contact is moved in cooperation with a rotational operation of the elevating arm. The movable contact holds a connection contact state between a power collector ring and a fixing contact point at the time of stopping a rotation of the movable contact assembly. The movable contact holds a contact point non-connection state between the power collector ring and the fixing contact point at the time of the rotation and the driving of the movable contact point assembly. A switching operation of the rotational stop and the rotational driving of the movable contact point assembly is performed in the contact point non-connection state.SELECTED DRAWING: Figure 7
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Description

[Technical Field]

[0001] SUMMARY OF THE INVENTION An embodiment of the present invention relates to a movable contact drive mechanism for a tap selector. [Background technology]

[0002] An on-load tap changer is a device that changes taps while a transformer is in operation (on load). Generally, an on-load tap changer comprises a tap selector and a diverter switch. The tap selector selects a tap to operate in the transformer tap winding. The diverter switch switches the circuit to the selected tap. The tap selector comprises a movable contact that is movable toward a fixed contact. When selecting a tap to operate, the movable contact is connected to the fixed contact. The tap selector comprises a Geneva gear that rotates in conjunction with the rotation of the Geneva driver. The movable contact moves in conjunction with the rotation of the Geneva gear, repeatedly coming into contact with and separating from the fixed contact. For example, a tap selector is equipped with a rolling contact type contact (roller contact) that uses a roller. In the case of a roller contact, depending on the contact state with the roller, the contact durability (durability) may be poor due to load and wear during switching. On the other hand, in order to open and close the contacts, a dedicated Geneva drive mechanism may be newly added, which increases the number of parts, resulting in increased space and costs. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 4231866 [Patent Document 2] Special Publication No. 6-52688 Summary of the Invention [Problem to be solved by the invention]

[0004] The problem to be solved by the present invention is to provide a movable contact drive mechanism for a tap selector that can reduce the load during switching, has excellent durability, and can prevent an increase in the number of parts. [Means for solving the problem]

[0005] The movable contact drive mechanism of the tap selector of the embodiment has a movable contact assembly. The movable contact assembly rotates in a circumferential direction around a reference axis. The movable contact assembly includes a drive slider, a lift arm, and a movable contact. The drive slider slides in a radial direction perpendicular to an axial direction along the reference axis. The lift arm rotates in conjunction with the sliding movement of the drive slider. The movable contact moves in conjunction with the rotation movement of the lift arm. The movable contact maintains a contact state between the current collecting ring and the fixed contact when the movable contact assembly stops rotating. The movable contact maintains a contactless state between the current collecting ring and the fixed contact when the movable contact assembly is rotationally driven. The operation of stopping rotation and switching between rotational drive of the movable contact assembly is performed in the contactless state. [Brief explanation of the drawings]

[0006] [Figure 1] FIG. 1 is a perspective view of an on-load tap changer according to an embodiment. [Figure 2] FIG. 2 is a perspective view of a tap selector according to an embodiment. [Figure 3] FIG. [Figure 4] FIG. 4 is an enlarged perspective view of the state in FIG. 3 with the cover and the like removed. [Figure 5] FIG. 4 is a perspective view of a contact portion between the movable contact assembly and the current collecting ring according to the embodiment. [Figure 6] FIG. 4 is a perspective view of a contact portion between the movable contact assembly and the fixing ring according to the embodiment. [Figure 7] FIG. 2 is an exploded perspective view of the movable contact assembly according to the embodiment, seen from above. [Figure 8] FIG. 10 is another exploded perspective view of the movable contact assembly of the embodiment, seen from above. [Figure 9] FIG. 2 is a perspective view including a movable contact, a lift arm, and a drive slider according to the embodiment. [Figure 10] 5A and 5B are explanatory diagrams illustrating the relationship between a movable contact, a lift arm, and a drive slider in the embodiment. [Figure 11] FIG. 2 is a perspective view including a movable contact and a lifting arm according to the embodiment. [Figure 12] FIG. 2 is a plan view including a movable contact assembly, a current collecting ring, and a fixing ring according to an embodiment. [Figure 13] 4A and 4B are explanatory diagrams illustrating the arrangement of a movable contact assembly according to the embodiment. [Figure 14] FIG. 10 is a plan view illustrating a switching operation by the movable contact assembly of the embodiment when the contacts are closed. [Figure 15] 5A and 5B are explanatory diagrams illustrating the relationship between the movable contact, the lift arm, and the drive slider when the contacts are closed in the embodiment. [Figure 16] 5A and 5B are explanatory diagrams illustrating the relationship between the drive roller and the guide groove when the electrodes are closed in the embodiment. [Figure 17] FIG. 4 is an explanatory diagram of the arrangement of the movable contact assembly when the contacts are closed in the embodiment. [Figure 18] FIG. 15 is a plan view of the embodiment during the contact opening operation, following FIG. [Figure 19] 16 is an explanatory diagram following FIG. 15 showing the relationship between the movable contact, the lift arm, and the drive slider during the contact-opening operation of the embodiment. [Figure 20] 17 is an explanatory diagram following FIG. 16 showing the relationship between the drive roller and the guide groove during the pole-opening operation of the embodiment. [Figure 21] 18 is an explanatory diagram following FIG. 17 showing the arrangement of the movable contact assembly during the contact opening operation of the embodiment. [Figure 22] FIG. 19 is a plan view following FIG. 18 when contact opening is completed in the embodiment. [Figure 23] 19A to 19C are explanatory diagrams illustrating the relationship between the movable contact, the lifting arm, and the drive slider when contact opening is completed in the embodiment, following FIG. [Figure 24] 21 is an explanatory diagram following FIG. 20 showing the relationship between the drive roller and the guide groove when the pole-opening operation is completed in the embodiment. [Figure 25] 22 is an explanatory diagram following FIG. 21 showing the arrangement of the movable contact assembly when contact opening is completed in the embodiment. [Figure 26] FIG. 10 is a plan view illustrating the torque of the switching operation by the movable contact assembly of the embodiment. [Figure 27]10A and 10B are side views for explaining torque of a switching operation by the movable contact assembly of the embodiment. [Figure 28] FIG. 10 is a perspective view of a tap selector of Comparative Example 1. [Figure 29] FIG. 10 is a perspective view of a movable contact assembly structure of Comparative Example 1. [Figure 30] FIG. 10 is a plan view of the movable contact assembly structure of Comparative Example 1. [Figure 31] FIG. 4 is a partially enlarged view of the movable contact assembly structure of Comparative Example 1. [Figure 32] FIG. 10 is an explanatory diagram of a product container according to Comparative Example 1. [Figure 33] FIG. 10 is a perspective view of a tap selector of Comparative Example 2. [Figure 34] FIG. 10 is a perspective view of an opening / closing drive concave-convex cam portion of Comparative Example 2. [Figure 35] FIG. 10 is an explanatory diagram of the contact opening operation of Comparative Example 2. [Figure 36] FIG. 10 is an explanatory diagram of Comparative Example 2 when electrodes are closed. [Figure 37] FIG. 10 is a cross-sectional view of a tap selector of Comparative Example 3. [Figure 38] FIG. 10 is a configuration diagram of a movable contact portion of Comparative Example 3. [Figure 39] FIG. 11 is an exploded perspective view of a tap selector according to a third comparative example. DETAILED DESCRIPTION OF THE INVENTION

[0007] Hereinafter, a movable contact drive mechanism of a tap selector according to an embodiment will be described with reference to the drawings.

[0008] Fig. 1 is a perspective view of an on-load tap changer 1 according to an embodiment, and Fig. 2 is a perspective view of a tap selector 2 according to an embodiment. The on-load tap changer 1 is a device that adjusts voltage by changing the turns ratio (transformation ratio) of a transformer during operation. As shown in Figures 1 and 2, the on-load tap changer 1 includes a tap selector 2, a drive mechanism 3, a reduction gear mechanism 4, a diverter switch 5, and an oil tank 6.

[0009] The tap selector 2 selects the tap to operate on in the transformer tap winding. The drive mechanism 3 drives the tap selector 2 by a driving force transmitted from an electric operating device (not shown) via a drive shaft 7 . The speed reducing mechanism 4 reduces the rotation speed of the rotational motion transmitted to the drive shaft 7 from an electric operating device (not shown).

[0010] The diverter switch 5 switches the circuit to the selected tap. The diverter switch 5 is placed inside the oil tank 6. The diverter switch 5 is immersed in insulating oil inside the oil tank 6. The diverter switch 5 has multiple tap terminals (not shown). The multiple tap terminals are connected to the tap selector 2 by wiring 8. Current is transmitted between them by the wiring 8. The diverter switch 5 is attached to the top of the tap selector 2 by mounting legs 10. A rotational driving force is transmitted to the drive mechanism 3 by the drive shaft 7, and tap switching is performed.

[0011] A drive coupling 11 is attached to the lower part of the drive shaft 7. The driving force transmitted via the drive shaft 7 rotates a drive transmission gear train, a drive coupling, etc. (not shown) via the drive coupling 11. The rotation of the drive coupling, etc., rotates a Geneva driver 25. The rotation of the Geneva driver 25 rotates a Geneva gear 26 (an example of a reference member).

[0012] The Geneva gear 26 is disposed concentrically with a reference axis G (the central axis of the insulating support cylinder 27). Hereinafter, the direction along the reference axis G will be referred to as the "axial direction", the direction perpendicular to the axial direction as the "radial direction", and the direction around the reference axis G as the "circumferential direction". In the embodiment, the axial direction is the direction perpendicular to the horizontal direction (the up-down direction). In the embodiment, the circumferential direction of the Geneva gear 26 coincides with the rotation direction of the Geneva gear 26.

[0013] Generally, tap selectors are classified into a single switching method and a parallel switching method. The single switching method is a method in which two movable contacts are operated simultaneously, and one movable contact is switched without current while the other movable contact remains energized. The parallel switching method is a method in which both movable contacts are operated only with no current, and odd and even taps are alternately switched in parallel. In the embodiment, a tap selector capable of parallel switching using a single Geneva gear will be described.

[0014] The Geneva gear 26 is supported by an insulating support tube 27. The insulating support tube 27 is provided with three-phase units 111U, 111V, and 111W corresponding to the three phases of U, V, and W. The three-phase units 111U, 111V, and 111W include a U-phase unit 111U corresponding to the U phase, a V-phase unit 111V corresponding to the V phase, and a W-phase unit 111W corresponding to the W phase. The three-phase units 111U, 111V, and 111W are arranged in the order of U-phase unit 111U, V-phase unit 111V, and W-phase unit 111W from the top. For example, the top side of each of the phase units 111U, 111V, and 111W corresponds to the odd-numbered tap side. For example, the bottom side of each of the phase units 111U, 111V, and 111W corresponds to the even-numbered tap side.

[0015] The tap selector 2 of the embodiment includes an upper plate 20, a lower plate 21, and support posts 22A and 22B. The upper plate 20 and the lower plate 21 each extend horizontally. The upper plate 20 supports the upper part of the tap selector 2. The lower plate 21 supports the lower part (bottom) of the tap selector 2. The pillars 22A and 22B extend in the vertical direction and connect the upper plate 20 and the lower plate 21. A plurality of pillars 22A and 22B are provided.

[0016] The tap selector 2 includes a plurality of changers 110, 120 for switching contacts. The plurality of changers 110, 120 includes a main changer 110 and a sub changer 120 connected to the main changer 110 via a Geneva driver 25. For example, the main changer 110 switches taps sequentially, and the sub changer 120 switches the connections of the tap windings. The plurality of supports 22A, 22B includes a main support 22A that supports the main changer 110 and a sub support 22B that supports the sub changer 120.

[0017] In this embodiment, the drive posts 40 in the main switch 110 and the sub switch 120 hold corresponding movable contact assemblies 50. The movable contact assemblies 50 are configured to be linked to the rotation of the Geneva gear 26, thereby being driven independently of each other.

[0018] In this embodiment, the upper side (odd tap side) and lower side (even tap side) of each phase unit 111U, 111V, 111W of the main switch 110 and the movable contact assembly 50 of the sub switch 120 are the same parts. This allows for the use of multiple identical parts, thereby reducing parts costs and improving assembly ease.

[0019] Below, we will explain in detail the configuration of the main changeover switch 110 (movable contact drive mechanism 100) in the tap selector 2. The sub-changeover switch 120 has a similar configuration to the main changeover switch 110, so a detailed explanation will be omitted. Fig. 3 is a perspective view of the movable contact assembly 50 of the embodiment. Fig. 4 is an enlarged perspective view of Fig. 3 with the cover 80 and the like removed. Fig. 5 is a perspective view of the contact portion between the movable contact assembly 50 of the embodiment and the current collecting ring 30. Fig. 6 is a perspective view of the contact portion between the movable contact assembly 50 of the embodiment and the fixing ring 35.

[0020] 3 to 6, the movable contact drive mechanism 100 includes a movable contact assembly 50, a current collecting ring 30, a fixed ring 35, and a drive support 40. The movable contact assembly 50 rotates in the circumferential direction around a reference axis G.

[0021] The current collecting rings 30 are formed in a circular ring shape when viewed in the axial direction. The current collecting rings 30 are connected to the wiring 8. The current collecting rings 30 are arranged corresponding to the upper side (odd tap side) and lower side (even tap side) of each phase unit 111U, 111V, 111W.

[0022] The current collecting ring 30 has a guide groove 31 formed in a ring shape concentric with the reference axis G. The guide groove 31 has a constant radius portion 32 and a constricted portion 33. The constant radius portion 32 guides the drive roller 52 in the circumferential direction at a fixed position in the radial direction. The constricted portion 33 guides the drive roller 52 in a direction intersecting the circumferential direction. When viewed in the axial direction, the constricted portion 33 curves radially inward relative to the constant radius portion 32.

[0023] The fixed ring 35 supports the fixed contacts 36. The fixed ring 35 is formed in a ring shape concentric with the reference axis G. The fixed contacts 36 are connected to wiring (not shown) drawn from the transformer tap windings. The fixed rings 35 are arranged corresponding to the upper side (odd tap side) and lower side (even tap side) of each phase unit 111U, 111V, 111W.

[0024] The fixed ring 35 includes a fixed plate 37 formed in an annular shape when viewed in the axial direction. For example, the fixed plate 37 is formed of an insulating material such as insulating resin. A plurality of fixed contacts 36 are provided at intervals in the circumferential direction of the fixed plate 37.

[0025] A switching arm 41 that rotates around a reference axis G is attached to the drive support 40. The drive support 40 extends in the vertical direction along the reference axis G. The drive support 40 supports a plurality of movable contact assemblies 50, thereby driving them to rotate in the circumferential direction. The drive support 40 is arranged to correspond to the movable contact assemblies 50 on the upper side (odd tap side) and the movable contact assemblies 50 on the lower side (even tap side) of each phase unit 111U, 111V, 111W.

[0026] Below, we will explain the configuration of the upper-stage (odd-numbered tap side) movable contact assembly 50. The lower-stage (even-numbered tap side) movable contact assembly 50 has the same configuration as the upper-stage (odd-numbered tap side) movable contact assembly 50, so detailed explanation will be omitted. Fig. 7 is an exploded perspective view of the movable contact assembly 50 of the embodiment, as seen from above. Fig. 8 is another exploded perspective view of the movable contact assembly 50 of the embodiment, as seen from above. Fig. 9 is a perspective view including the movable contact 70, the lifting arm 60, and the drive slider 51 of the embodiment. Fig. 10 is an explanatory diagram of the relationship between the movable contact 70, the lifting arm 60, and the drive slider 51 of the embodiment. Fig. 11 is a perspective view including the movable contact 70 and the lifting arm 60 of the embodiment.

[0027] 7 to 11, the movable contact assembly 50 includes a drive slider 51, a drive roller 52, a horizontal guide roller 53, vertical guide rollers 54A and 54B, a guide holder 58, a lifting arm 60, a lifting roller 61, a movable contact 70, a biasing member 75, a cover 80, and a support holder 90.

[0028] The components of the movable contact assembly 50 are provided in pairs in the axial direction via the current collecting ring 30 and the fixed ring 35. The components of the movable contact assembly 50 are configured as a pair of identical parts that are inverted and facing each other with the current collecting ring 30 and the fixed ring 35 at the center. The movable contact assembly 50 is assembled in a state where components of the same type in the movable contact assembly 50 are stacked in order, inverted, on both sides of the current collecting ring 30 and the fixed ring 35 in the axial direction.

[0029] First, the configuration of the drive slider 51 will be described. The drive slider 51 is supported so as to be slidable in the radial direction relative to the Geneva gear 26. The drive slider 51 is formed of sheet metal. For example, the drive slider 51 is a component obtained by blanking and bending a metal sheet. The drive slider 51 is formed in an overall rectangular shape when viewed from the axial direction. The drive slider 51 has a rectangular shape in plan view with its elongated side in a direction perpendicular to the axial direction.

[0030] A drive roller 52 is attached to the drive slider 51. The drive roller 52 is rotatably supported by the drive slider 51. The drive roller 52 is rotatable around an axis in the axial direction (up and down direction). The drive roller 52 is disposed on the drive slider 51 at a portion facing the current collecting ring 30. The drive roller 52 is guided by the guide groove 31 of the current collecting ring 30.

[0031] The drive slider 51 has a bent protrusion 55. The bent protrusion 55 is provided in the central portion in the short direction of the drive slider 51. The bent protrusion 55 is bent in the axial direction toward the direction in which the pair of drive sliders 51 face each other. The bent protrusions 55 are provided in pair and spaced apart in the longitudinal direction of the drive slider 51.

[0032] The base of the bent protrusion 55 functions as a lifting / lowering pressing portion 56 that presses and rotates the lifting / lowering arm 60. The lifting / lowering pressing portion 56 rotates the lifting / lowering arm 60 by coming into contact with the lifting / lowering roller 61 due to the sliding movement of the drive slider 51. The lifting / lowering pressing portion 56 is provided integrally with the drive slider 51. The lifting / lowering pressing portion 56 is provided in two locations, on the current collecting ring 30 side and on the fixing ring 35 side.

[0033] Horizontal guide rollers 53 are attached to the drive slider 51. The horizontal guide rollers 53 are rotatably supported relative to the drive slider 51. The horizontal guide rollers 53 are rotatable around an axis in the axial direction (up and down direction). The horizontal guide rollers 53 guide the radial sliding movement of the drive slider 51 along the inner wall surface of the cover 80. A total of four horizontal guide rollers 53 (an example of multiple rollers) are arranged, one at each of the four corners (corresponding to the four corner portions) of the drive slider 51. The four horizontal guide rollers 53 are arranged on the surfaces of the pair of drive sliders 51 that face each other in the axial direction.

[0034] Vertical guide rollers 54A and 54B are attached to the drive slider 51. The vertical guide rollers 54A and 54B are rotatably supported relative to the drive slider 51. The vertical guide rollers 54A and 54B are rotatable around an axis in the longitudinal direction of the drive slider 51. The vertical guide rollers 54A and 54B are in rolling contact with the surfaces of the current collecting ring 30 and the fixed ring 35, respectively. Two vertical guide rollers 54A and 54B (an example of a plurality) are arranged on the drive slider 51, one on each side facing the current collecting ring 30 and the other facing the fixed ring 35. The two vertical guide rollers 54A and 54B are the current collecting side vertical guide roller 54A arranged on the current collecting ring 30 side, and the fixed side vertical guide roller 54B arranged on the fixed ring 35 side.

[0035] The drive slider 51 is guided in the planar direction (horizontal direction) by the inner wall surfaces on both sides of the cover 80 via horizontal guide rollers 53. In the movable contact assembly 50, the drive slider 51 performs a sliding movement in the longitudinal direction of the drive slider 51 (radial direction as viewed from the tap selector 2).

[0036] The drive slider 51 is guided in the vertical direction (axial direction) by the guide portions 34, 38 of the current collecting ring 30 and the fixed ring 35 via vertical guide rollers 54A, 54B. The drive slider 51 rotates (moves circumferentially) the movable contact assembly 50 around the reference axis G when switching the tap.

[0037] Next, the configuration of the lifting arm 60 will be described. The lifting arm 60 rotates in conjunction with the sliding movement of the drive slider 51. A pair of lifting arms 60 are provided facing each other in the longitudinal direction of the drive slider 51 (the radial direction as viewed from the tap selector 2). The lifting arms 60 are formed of an insulating material such as insulating resin.

[0038] A lifting roller 61 is attached to the lifting arm 60 via a roller support shaft 62. The roller support shaft 62 extends in a direction along the short side of the drive slider 51. The lifting roller 61 is rotatably supported by the lifting arm 60. The lifting roller 61 is rotatable around the roller support shaft 62. The lifting roller 61 abuts against the lifting pressing portion 56.

[0039] The lifting arm 60 is attached to shaft holes 85 formed in both wall surfaces of the cover 80 via arm fulcrum shafts 63. The arm fulcrum shafts 63 extend parallel to the roller support shafts 62. The lifting arm 60 is rotatable around the arm fulcrum shafts 63. The lifting arm 60 rotates around the arm fulcrum shafts 63 due to the sliding movement of the drive slider 51.

[0040] In this embodiment, a plurality of movable contacts 70 (three in the illustrated example) are provided. The lifting arm 60 has a plurality of arm protrusions 64 that simultaneously lift and lower the plurality of movable contacts 70. The lifting arm 60 has a plurality of partitions 65 that separate the movable contacts 70. The lifting arm 60 is integrally provided with a plurality of partitions 65 (four in the illustrated example) corresponding to the number of movable contacts 70. The arm protrusions 64 are disposed between the partitions 65. The plurality of partitions 65 are disposed at intervals from one another so that the movable contacts 70 can move in a direction oblique to the circumferential direction when the movable contact assembly 50 rotates in the circumferential direction.

[0041] Next, the movable contact 70 will be described. The movable contact 70 moves in conjunction with the rotation of the lifting arm 60. When the rotation of the movable contact assembly 50 is stopped, the movable contact 70 maintains a contact contact state CS between the current collecting ring 30 and the fixed contact 36. The contact contact state CS corresponds to a closed state in which the movable contact 70 and the fixed contact 36 are electrically connected to each other. When the movable contact assembly 50 is driven to rotate, the movable contact 70 maintains a contact non-contact state NC between the current collecting ring 30 and the fixed contact 36. The contact non-contact state NC corresponds to an open state in which the movable contact 70 and the fixed contact 36 are not electrically connected to each other. In this embodiment, the switching operation between stopping rotation and driving rotation of the movable contact assembly 50 is performed in the contact non-contact state NC.

[0042] The movable contact 70 has a longitudinal direction perpendicular to the axial direction. The movable contact 70 has contact notches 71A and 71B. The contact notches 71A and 71B are formed in a portion of the movable contact 70 facing the current collecting ring 30 and a portion facing the fixed ring 35. The two contact notches 71A and 71B are a current collecting-side notch 71A formed on the current collecting ring 30 side and a fixed-side notch 71B formed on the fixed ring 35 side.

[0043] The movable contact 70 has a central protrusion 72 that protrudes from the radial center of the movable contact 70 so as to be sandwiched between the pair of lifting arms 60. The central protrusion 72 protrudes from the radial center of the movable contact 70 toward the longitudinal center of the drive slider 51. The movable contact 70 has a central recess 73 in which a biasing member 75 is disposed, at a position that overlaps with the central protrusion 72 when viewed in the axial direction. The central protrusion 72 is disposed on the central axis of the biasing member 75 that is disposed in the central recess 73.

[0044] In this embodiment, the lifting arm 60 and related parts (such as the lifting pressing portion 56 that drives the lifting arm 60) are provided in two locations, one on the current collecting ring 30 side and one on the fixed ring 35 side. A biasing member 75 is disposed between the movable contact 70 and the cover 80. The biasing member 75 biases the movable contact 70. For example, the biasing member 75 is a coil spring. The movable contact 70 is biased by the biasing member 75 onto the arm protrusions 64 of the lifting arms 60 on the current collecting ring 30 side and the fixed ring 35 side at the collector-side notch 71A and the fixed-side notch 71B. The movable contact 70 moves up and down due to the synchronized rotation of the pair of lifting arms 60.

[0045] In this embodiment, each of the pair of lifting arms 60 has partitions 65 and arm protrusions 64 corresponding to the multiple movable contacts 70, so that the multiple movable contacts 70 move up and down simultaneously. Therefore, the movable contact assembly 50 is configured so that the sliding movement of the drive slider 51 within the movable contact assembly 50 causes the multiple movable contacts 70 to move up and down simultaneously.

[0046] Next, the cover 80 and the support holder 90 will be described. The cover 80 covers the drive slider 51, the lifting arm 60, and the movable contact 70. The cover 80 rotatably supports the lifting arm 60. The support holder 90 supports the cover 80. The support holder 90 has a plurality of engagement protrusions 91. The cover 80 has a plurality of engagement cutouts 81 corresponding to the number of engagement protrusions 91. The engagement protrusions 91 and the engagement cutouts 81 limit the movement of the cover 80 in the planar direction (horizontal direction) relative to the support holder 90.

[0047] The support holder 90 has a plurality of engagement hooks 92. The cover 80 has a plurality of engagement protrusions 82. The cover 80 has a plurality of engagement holes 83 corresponding to the number of the engagement protrusions 82. The support holder 90 and the cover 80, like the biasing member 75, the movable contact 70, the lifting arm 60, and the drive slider 51, are configured as a pair of identical parts that are inverted and faced with the current collecting ring 30 and the fixing ring 35 at the center.

[0048] The pair of support holders 90 and covers 80 are configured to sandwich the current collecting ring 30 and the fixing ring 35. The pair of support holders 90 and covers 80 are configured to assemble the movable contact assembly 50 by the engagement of the multiple engagement hooks 92 with each other and the engagement of the multiple engagement protrusions 82 and engagement holes 83. The engagement portions and component attachment portions of the components of the movable contact assembly 50 are formed so that each component (the same component) that makes up a pair can be used upside down.

[0049] The pair of opposing drive sliders 51 abut against each other at opposing ends (corresponding to abutment portions 57) of the bending protrusions 55. The pair of drive sliders 51 are fixed in the planar direction (horizontal direction) by the support holder 90, thereby forming an integrated structure.

[0050] The support holder 90 has an opening 93 that opens in the axial direction. The drive support post 40 is inserted into the opening 93 of the support holder 90. The drive support post 40 is driven by the rotation of the Geneva gear 26, thereby rotating the movable contact assembly 50 around the reference axis G (around the central axis of the tap selector 2).

[0051] Next, the mechanism of the sliding action of the drive slider 51 will be described. Fig. 12 is a plan view including the movable contact assembly 50 of the embodiment, the current collecting ring 30, and the fixing ring 35. Fig. 13 is an explanatory diagram of the arrangement of the movable contact assembly 50 of the embodiment. As described above, the current collecting ring 30 has the guide groove 31 that engages with the drive roller 52. The guide groove 31 is formed on the outer periphery of the current collecting ring 30. The guide groove 31 has a constricted portion 33 and a constant radius portion 32.

[0052] The constricted portions 33 are formed to correspond to the phase angles of the fixed contacts 36. In the example shown in the figure, the constricted portions 33 are formed to correspond to the phase angles (corresponding to a central angle of 60 degrees) of six fixed contacts 36 that are arranged at equal intervals in the circumferential direction in a plan view. The constant radius portions 32 are formed to correspond to the tap changing midpoints. The constant radius portions 32 are formed between the constricted portions 33 in the circumferential direction of the guide groove 31.

[0053] At the tap change midpoint, the movable contact 70 is held in an open state (corresponding to the contact non-contact state NC) by the action of the constant radius portion 32. At a position near the fixed contact 36, the sliding movement of the drive slider 51 is controlled by the action of the constricted portion 33 so that the movable contact 70 comes into contact with or separates from the current collecting ring 30 and the fixed contact 36.

[0054] The fixed ring 35 has a plurality of fixed contacts 36. The fixed contacts 36 are arranged at equal intervals in the circumferential direction of the fixed ring 35. A drive support 40 is attached to a switching arm 41 that rotates around a reference axis G. The rotation of the switching arm 41 causes the movable contact assembly 50 to rotate around the reference axis G via the drive support 40.

[0055] As described above, the pair of opposing current collecting side vertical guide rollers 54A are arranged to sandwich the guide portion 34 of the current collecting ring 30. The pair of opposing fixed side vertical guide rollers 54B are arranged to sandwich the guide portion 38 of the fixed ring 35. This allows the movable contact assembly 50 to rotate while being guided by the guide portions 34, 38 of both the current collecting ring 30 and the fixed ring 35.

[0056] A pair of opposing drive rollers 52 are engaged with guide grooves 31 on both sides of the current collecting ring 30. The movable contact assembly 50 includes a pair of drive sliders 51 joined together by a support holder 90. The movable contact assembly 50 is configured so that each drive roller 52 of the pair of drive sliders 51 is guided by the guide groove 31 to perform a sliding motion.

[0057] As described above, in this embodiment, a pair of drive sliders 51 are provided facing each other in the axial direction. The drive sliders 51 are configured so that an open-contact holding force that maintains the contact non-contact state NC between the current collecting ring 30 and the fixed contact 36 acts in the axial direction. The pair of drive sliders 51 include abutment portions 57 that abut against each other so as to cancel out the open-contact holding force. In this embodiment, the abutment portion 57 corresponds to the tip portion of the bent protrusion 55 (the portion opposite the base portion).

[0058] The guide holder 58 guides the abutment portion 57 of the drive slider 51 in the axial direction. The guide holder 58 is formed in a rectangular cylindrical shape extending in the axial direction. A pair of guide holders 58 are provided at an interval in the longitudinal direction of the drive slider 51 (the radial direction as viewed from the tap selector 2). Half of the bending protrusions 55 of the pair of upper and lower drive sliders 51 fit into the guide holder 58, so that the tip portions of the bending protrusions 55 (corresponding to the abutment portion 57) abut against each other.

[0059] The operation of the movable contact assembly 50 will now be described, starting from the closing operation through the opening operation and ending with the completion of opening. Fig. 14 is a plan view illustrating the switching operation of the movable contact assembly 50 of the embodiment when the contact is closed. Fig. 15 is an explanatory diagram illustrating the relationship between the movable contact 70, the lift arm 60, and the drive slider 51 when the contact is closed in the embodiment. Fig. 16 is an explanatory diagram illustrating the relationship between the drive roller 52 and the guide groove 31 when the contact is closed in the embodiment. Fig. 17 is an explanatory diagram illustrating the arrangement of the movable contact assembly 50 when the contact is closed in the embodiment.

[0060] When contact is closed, current is always flowing. When contact is closed, the movable contact assembly 50 stops at the position of the fixed contact 36. When contact is closed, the drive roller 52 is positioned in the constricted portion 33. When contact is closed, the drive slider 51 is positioned at the innermost periphery. When contact is closed, the lift roller 61 stops by abutting against the lift pressing portion 56. When contact is closed, the arm protrusion 64 is at the lowest position. When contact is closed, the biasing force of the biasing member 75 causes the current collecting side contact portion of the movable contact 70 and the current collecting ring 30, and the fixed side contact portion and the fixed contact 36 to come into contact first.

[0061] Therefore, when the contacts are closed, a gap S is generated between the arm projection 64 and the contact cutouts 71A, 71B as shown by the arrows in Figure 15. This reduces the load when the contacts are next switched.

[0062] Next, the contact opening operation will be described. Fig. 18 is a plan view of the embodiment during the contact opening operation, following Fig. 14. Fig. 19 is an explanatory diagram of the relationship between the movable contact 70, the lift arm 60, and the drive slider 51 during the contact opening operation, following Fig. 15. Fig. 20 is an explanatory diagram of the relationship between the drive roller 52 and the guide groove 31 during the contact opening operation, following Fig. 16. Fig. 21 is an explanatory diagram of the arrangement of the movable contact assembly 50 during the contact opening operation, following Fig. 17.

[0063] The opening operation is the start of the switching operation. During the opening operation, the positional relationship is such that the movable contact 70 rotates counterclockwise (in the direction of arrow R) when viewed from above. During the opening operation, the drive roller 52 is pressed toward the outer periphery (radially outward) of the current collecting ring 30 by the action of the constricted portion 33. As a result, the drive slider 51 slides toward the outer periphery (radially outward) of the current collecting ring 30. Then, the lifting / lowering pressing portion 56 presses the lifting / lowering roller 61. This causes the lifting / lowering arm 60 to rotate. Then, the arm protrusion 64 comes into contact with the contact cutouts 71A and 71B, thereby lifting the movable contact 70. This releases contact between the current collecting side contact portion and the current collecting ring 30 and between the fixed side contact portion and the fixed contact 36 of the movable contact 70.

[0064] Therefore, during the contact opening operation, the current collecting ring 30 and the fixed contact 36 are not in contact with each other, and a gap S is created as shown between the arrows (thin arrows) in Figure 21. In other words, the contacts transition to an open state (when opening is complete).

[0065] Next, the time when the contact opening is completed will be described. Fig. 22 is a plan view of the embodiment at the time of completion of contact opening, following Fig. 18. Fig. 23 is an explanatory diagram of the relationship between the movable contact 70, the lift arm 60, and the drive slider 51 at the time of completion of contact opening, following Fig. 19. Fig. 24 is an explanatory diagram of the relationship between the drive roller 52 and the guide groove 31 at the time of completion of contact opening, following Fig. 20. Fig. 25 is an explanatory diagram of the arrangement of the movable contact assembly 50 at the time of completion of contact opening, following Fig. 21.

[0066] The contact opening completion time is when the contacts are completely opened after the contact opening operation. At the contact opening completion time, the positional relationship is such that the rotation has progressed further counterclockwise (in the direction of arrow R) in top view compared to the contact opening operation. At the contact opening completion time, the drive roller 52 is positioned in the constant radius portion 32. At the contact opening completion time, the drive slider 51 is positioned in the outermost periphery. At the contact opening completion time, the lift roller 61 abuts against the flat pressing portion (corresponding to the flat portion of the drive slider 51). At the contact opening completion time, the movable contact 70 is maintained at the same height via the lift arm 60. At the contact opening completion time, the current collecting ring 30 and the fixed contact 36 are kept out of contact with each other, and the gap S is also maintained as shown between the arrows (thin arrows) in FIG. 25.

[0067] Therefore, when the contacts are completely opened, no reaction force is generated in the sliding direction of the drive slider 51. When the contacts are completely opened, the contact pressure acting in the vertical direction is canceled out at the ends (contact portions 57) of the pair of opposing bent protrusions 55. Therefore, the movable contact assembly 50 is driven with an extremely low load.

[0068] When the rotation proceeds further than when the opening is completed, the movable contact assembly 50 approaches the angle of the tap change destination. Then, due to the reversible operation shown in Figures 18 to 21, the current collecting ring 30 and the fixed contact 36 come into contact with each other, and the state returns to the closed state.

[0069] In this embodiment, the switching operation between rotation stop and rotation drive of the movable contact assembly 50 is performed in a contact non-contact state NC, where the current collecting ring 30 and the fixed contacts 36 are not in contact with each other. Therefore, the load torque during switching can be significantly reduced compared to when the switching operation is performed while the current collecting ring 30 and the fixed contacts 36 are in contact with each other. In addition, contact wear due to sliding can be suppressed. Furthermore, after the contacts are opened, the rotation operation can be performed without the movable contact assembly 50 bearing the open contact holding force. Therefore, improved durability and reliability can be expected with a low load. In addition, the switching operation begins from the stopped position of the movable contact assembly 50, so the load torque during contact opening can be kept low.

[0070] Next, a method for reducing the load torque will be described. Fig. 26 is a plan view for explaining the torque of the switching operation by the movable contact assembly 50 of the embodiment. Fig. 27 is a side view for explaining the torque of the switching operation by the movable contact assembly 50 of the embodiment.

[0071] P0 to P4 shown in FIGS. 26 and 27 represent loads. P is the load acting on the drive roller 52. P0 is the biasing force of the biasing member 75. P1 is the tangential component of the load acting on the drive roller 52. P2 is the radial component of the load acting on the drive roller 52. P3 is the horizontal component of the opening reaction force acting on the lifting and pressing portion 56. P4 is the switching load acting on the drive support 40.

[0072] As a reaction force to P0, P3 is determined according to the contact angle of the lift-up / lower-down pressing portion 56. P2, which corresponds to P3, is four times P3 (P3 × 4). A component force P1, which is determined by the contact wall surface angle of the constricted portion 33 relative to P2, becomes a tangential external force acting on the movable contact assembly 50.

[0073] In this embodiment, the constricted portion 33 curves radially inward relative to the constant radius portion 32 when viewed from the axial direction. This allows the distance L1 from the central axis of the P1 load point to be set relatively small, thereby enabling the load torque (P1 x L1) to be reduced.

[0074] Furthermore, the load P4 that rotates the movable contact assembly 50 against P1 is determined by the relationship P4×L2=P1×L1. In this embodiment, L2 is much longer than L1 (L2>>L1). Therefore, P4 acting between the drive column 40 and the movable contact assembly 50 is a smaller load than P1. This improves the durability and reliability of related components, and enables them to be made smaller, thinner, and made of resin. This, in turn, enables cost reduction and space saving.

[0075] As described above, the movable contact drive mechanism 100 of the tap selector 2 of this embodiment has the movable contact assembly 50. The movable contact assembly 50 rotates in the circumferential direction around the reference axis G. The movable contact assembly 50 includes the drive slider 51, the lift arm 60, and the movable contact 70. The drive slider 51 slides in the radial direction perpendicular to the axial direction along the reference axis G. The lift arm 60 rotates in conjunction with the sliding movement of the drive slider 51. The movable contact 70 moves in conjunction with the rotation of the lift arm 60. The movable contact 70 maintains a contact contact state CS between the current collecting ring 30 and the fixed contact 36 when the movable contact assembly 50 is stopped from rotating. The movable contact 70 maintains a contact non-contact state NC between the current collecting ring 30 and the fixed contact 36 when the movable contact assembly 50 is driven to rotate. The operation of switching between stopping and driving the rotation of the movable contact assembly 50 is performed in the contact non-contact state NC. The above configuration provides the following effects. Because the switching operation is performed in the non-contact state NC, no rolling or sliding contact occurs during the switching operation, so contact durability (durability) is not compromised. In addition, there is no need to add a dedicated Geneva drive mechanism to open and close the contacts. In other words, the simple configuration provided within the movable contact assembly 50 allows for switching without rolling or sliding contact. This reduces the load during switching, provides excellent durability, and prevents an increase in the number of parts.

[0076] The current collecting ring 30 of this embodiment has a guide groove 31 formed in a ring shape concentric with the reference axis G. The movable contact assembly 50 further includes a drive roller 52 rotatably supported on the drive slider 51 and guided by the guide groove 31, a cover 80 that covers the drive slider 51, the lifting arm 60, and the movable contact 70, and a biasing member 75 that is disposed between the cover 80 and the movable contact 70 and biases the movable contact 70. The above-described configuration provides the following effects. The biasing force of the biasing member 75 allows the drive slider 51, drive roller 52, lifting arm 60, and movable contact 70 to be positioned relative to the current collecting ring 30. Therefore, the components within the movable contact assembly 50 can operate more stably and smoothly.

[0077] The guide groove 31 of this embodiment includes a constant radius portion 32 that guides the drive roller 52 in the circumferential direction at a fixed radial position, and a constricted portion 33 that guides the drive roller 52 in a direction intersecting the circumferential direction. When viewed from the axial direction, the constricted portion 33 curves radially inward relative to the constant radius portion 32. The above-described configuration provides the following effects. Compared to when the constricted portion 33 curves radially outward relative to the constant radius portion 32 as viewed axially, the distance from the point of application of the load acting on the drive roller 52 to the reference axis G during switching can be made shorter. This reduces the load torque during switching. This in turn improves the durability and reliability of related parts, enables parts to be made smaller and thinner, or made of resin, and reduces costs and space.

[0078] In this embodiment, multiple movable contact assemblies 50 are arranged along the axial direction. The movable contact drive mechanism 100 further includes drive pillars 40 that extend along the axial direction and support the multiple movable contact assemblies 50, thereby driving them to rotate in the circumferential direction. The above configuration provides the following effects. The drive support 40 can simultaneously rotate and drive multiple movable contact assemblies 50. Therefore, compared to a case where separate drive members are provided for multiple movable contacts 70, the configuration can be simplified and an increase in the number of parts can be suppressed.

[0079] The movable contact drive mechanism 100 of this embodiment further includes a fixed ring 35 formed concentrically with the reference axis G and supporting the fixed contact 36. The movable contact assembly 50 is assembled by stacking components of the same type in the movable contact assembly 50 upside down in order on both sides of the current collecting ring 30 and the fixed ring 35 in the axial direction. The above configuration provides the following effects. Even when the movable contact assembly 50 is assembled from both sides of the current collecting ring 30 and the fixed ring 35 in the axial direction, common components can be used, thereby preventing an increase in the number of components.

[0080] In this embodiment, a pair of drive sliders 51 are provided facing each other in the axial direction. The drive sliders 51 are configured so that an open-contact holding force that maintains the contact non-contact state NC acts in the axial direction between the current collecting ring 30 and the fixed contact 36. The pair of drive sliders 51 have abutment portions 57 that abut against each other so as to cancel out the open-contact holding force. The above configuration provides the following effects. The open pole holding force is cancelled out by the contact portions 57 of the pair of drive sliders 51, so that the switching drive load (such as the load acting on the drive roller 52 during switching) can be minimized. This makes it possible to improve the durability and reliability of related parts, make parts smaller and thinner, or use resin, and reduce costs and space.

[0081] The movable contact assembly 50 of this embodiment further includes a guide holder 58 that guides the abutting portion 57 of the drive slider 51 in the axial direction. The above-described configuration provides the following effects. The contact portions 57 of the drive sliders 51 are guided in the axial direction by the guide holders 58, thereby preventing the open-contact holding force from acting in directions other than the axial direction. Therefore, the open-contact holding forces can be more stably cancelled out by the contact portions 57 of the pair of drive sliders 51. This makes it possible to significantly reduce the switching drive load (such as the load acting on the drive rollers 52 during switching).

[0082] The movable contact assembly 50 of this embodiment further comprises a cover 80 that covers the drive slider 51, the lifting arm 60, and the movable contact 70, a plurality of horizontal guide rollers 53 that are rotatably supported by the drive slider 51 and guide the radial sliding movement of the drive slider 51 along the inner wall surface of the cover 80, and a plurality of vertical guide rollers 54A, 54B that are rotatably supported by the drive slider 51 and come into rolling contact with the surfaces of the current collecting ring 30 and the fixed ring 35. The above configuration provides the following effects. The cover 80 can protect the drive slider 51, the lifting arm 60, and the movable contact 70 from external factors. In addition, the multiple horizontal guide rollers 53 can smoothly guide the radial movement of the drive slider 51 along the inner wall surface of the cover 80. In addition, the multiple vertical guide rollers 54A, 54B can limit the position of the movable contact assembly 50 in the height direction (axial direction).

[0083] The drive slider 51 of this embodiment is formed in a rectangular shape when viewed in the axial direction. A total of four horizontal guide rollers 53 are arranged, one at each of the four corners of the drive slider 51 when viewed in the axial direction. A total of two vertical guide rollers 54A, 54B are arranged, one each at portions of the drive slider 51 facing the current collecting ring 30 and the fixed ring 35. The above configuration provides the following effects. The four horizontal guide rollers 53 can smoothly guide the radial movement of the drive slider 51 along the inner wall surface of the cover 80. In addition, the two vertical guide rollers 54A and 54B can limit the height (axial) position of the movable contact assembly 50. Therefore, a stable sliding operation of the drive slider 51 can be achieved with the minimum necessary number of horizontal guide rollers 53 and vertical guide rollers 54A and 54B.

[0084] The movable contact assembly 50 of this embodiment includes a cover 80 that covers the drive slider 51, lift arm 60, and movable contact 70 and rotatably supports the lift arm 60, and a lift roller 61 that is rotatably supported relative to the lift arm 60. The drive slider 51 includes a lift pressing portion 56 that rotates the lift arm 60 by coming into contact with the lift roller 61 as the drive slider 51 slides. The above-described configuration provides the following effects. The lifting arm 60 can be rotated by the contact of the lifting pressing portion 56 of the drive slider 51. Therefore, compared to a case where a separate member for rotating the lifting arm 60 is provided, the configuration can be simplified and an increase in the number of parts can be suppressed.

[0085] In this embodiment, a plurality of movable contacts 70 are provided. The lifting arm 60 includes a plurality of arm protrusions 64 that simultaneously lift and lower the plurality of movable contacts 70, and a plurality of partition portions 65 that separate the movable contacts 70. The above-described configuration provides the following effects. The multiple movable contacts 70 ensure a sufficient contact area, thereby increasing the current-carrying capacity. This allows for larger currents. For example, providing multiple movable contacts 70 separately allows for manufacturing using sheet metal, thereby reducing costs. Additionally, the multiple arm protrusions 64 of the lifting arm 60 allow multiple movable contacts 70 to be simultaneously raised and lowered. Therefore, compared to providing separate components for raising and lowering the multiple movable contacts 70, the configuration can be simplified while minimizing the number of components. Furthermore, the partitions 65 separating the movable contacts 70 allow the movable contacts 70 to be raised and lowered more stably and smoothly.

[0086] The multiple partitions 65 of this embodiment are arranged at intervals from one another so that the movable contact 70 can move in a direction oblique to the circumferential direction when the movable contact assembly 50 rotates in the circumferential direction. The above configuration provides the following effects. This allows for a degree of freedom in the movement of the movable contact 70. Therefore, by moving the movable contact 70 in a direction oblique to the circumferential direction during switching, the contact pressure of the movable contact 70 can be reduced as much as possible.

[0087] In this embodiment, a pair of lifting arms 60 are provided facing each other in the radial direction. The movable contact 70 has a central protrusion 72 that protrudes from the radial center of the movable contact 70 so as to be sandwiched between the pair of lifting arms 60. The above-described configuration provides the following effects. The central protrusion 72 of the movable contact 70 is sandwiched between the pair of lifting arms 60, thereby restricting the radial position of the movable contact 70. Therefore, the lifting and lowering operation of the movable contact 70 can be performed more stably and smoothly.

[0088] The movable contact assembly 50 of this embodiment further includes a biasing member 75 that biases the movable contact 70. The movable contact 70 includes a central recess 73 in which the biasing member 75 is disposed, at a position that overlaps with the central protrusion 72 when viewed from the axial direction. The above configuration provides the following effects. The biasing force of the biasing member 75 acts on the central recess 73 of the movable contact 70, so that the biasing force can be applied in a balanced manner to both radial sides of the movable contact 70. Therefore, the operation of switching between rotation stop and rotation drive of the movable contact assembly 50 can be performed more stably and smoothly.

[0089] Conventionally, the movable contacts of the tap selector in on-load tap changers for gas are equipped with rolling contact type contacts (roller contacts) using rollers because they lack the lubrication function of insulating oil. In the case of roller contacts, depending on the contact state with the roller, the contact durability (durability) can be poor due to the load and wear during switching. For example, in the case of roller contacts, a large contact pressure is required to ensure a sufficient contact area, which limits the current carrying capacity. In addition, because the peripheral speed varies depending on the radius of the contact area, it is necessary to adjust the roller diameter to ensure rolling contact.

[0090] On the other hand, in order to open and close the contacts, a dedicated Geneva drive mechanism may be newly added, which increases the number of parts, resulting in increased space and costs.

[0091] The moving contacts of the tap selector in an on-load tap changer for oil use utilize the lubricating properties of insulating oil. For example, taps are changed by sliding the current collector ring, located at the center of rotation, in a constant state of contact. However, contact pressure must be kept low to reduce friction wear, which can be a hindrance to large currents.

[0092] According to this embodiment, the conventional problems are improved as follows. First, Comparative Examples 1 to 3 will be given as conventional examples, and the problems with each example will be explained.

[0093] Fig. 28 is a perspective view of a tap selector 1000 of Comparative Example 1. Fig. 29 is a perspective view of a movable contact assembly structure of Comparative Example 1. Fig. 30 is a plan view of the movable contact assembly structure of Comparative Example 1. Fig. 31 is a partially enlarged view of the movable contact assembly structure of Comparative Example 1. Fig. 32 is an explanatory diagram of a product of Comparative Example 1.

[0094] 28 to 32, the tap selector 1000 of Comparative Example 1 includes a roller movable contact assembly 1001, a Geneva mechanism 1002, a switching drive support 1003, a movable contact assembly support 1004, and a fixed contact support 1005. The roller movable contact assembly 1001 includes a plurality of roller current-carrying shaft assemblies 1006 (three each in the illustrated example) facing each other above and below. The plurality of roller current-carrying shaft assemblies 1006 are biased toward the center by biasing compression springs 1007. The plurality of roller current-carrying shaft assemblies 1006 are housed in a movable contact holder 1008. The movable contact holder 1008 is attached to the movable contact assembly support 1004. The movable contact assembly support 1004 is supported by the switching drive support 1003. The switching drive support 1003 rotates around the central axis of the tap selector 1000 due to the operation of the Geneva mechanism 1002. This causes the roller movable contact assembly 1001 to rotate around the same axis, thereby performing tap switching.

[0095] A current-collecting-side roller current-carrying part 1009 is formed on the center side of the roller current-carrying shaft assembly 1006. A fixed-side roller current-carrying part 1010 is formed on the outer periphery of the current-carrying shaft assembly 1006. Current is passed through the roller current-carrying parts 1009, 1010 when they come into contact with the current-collecting ring assembly 1011 and the fixed contact piece 1012 so as to sandwich them. When the tap is changed, the current-collecting-side roller current-carrying part 1009 maintains a rolling contact state. Meanwhile, the fixed-side roller current-carrying part 1010 temporarily moves away from the fixed contact piece 1012 and approaches the adjacent fixed contact piece 1012. As the roller current-carrying shaft assemblies 1006 are pushed apart in the pole-opening direction, the end of the fixed contact piece 1012 enters between the opposing roller current-carrying shaft assemblies 1006, restoring the contact state.

[0096] In Comparative Example 1, the current collecting ring assembly 1011 is always in rolling contact, so load torque is generated continuously during switching, and there is concern that contact resistance may increase due to wear debris during repeated switching. For example, to prevent an increase in load during switching, it is necessary to position the fixed contact piece 1012 as close to the center as possible in the gap between the opposing fixed-side roller current-carrying parts 1010. This requires height control and adjustment of the fixed contact side and the movable contact side, which increases the cost of parts and assembly. Basically, the contact area of ​​roller-shaped contacts (roller contacts) is small. Increasing the contact biasing force to increase the contact area is limited in terms of wear resistance and load torque. Therefore, it is difficult to increase the current capacity.

[0097] Next, comparative example 2 will be described. Fig. 33 is a perspective view of a tap selector 2000 of Comparative Example 2. Fig. 34 is a perspective view of an opening / closing drive concave-convex cam portion 2001 of Comparative Example 2. Fig. 35 is an explanatory diagram of Comparative Example 2 during a contact opening operation. Fig. 36 is an explanatory diagram of Comparative Example 2 during contact closing.

[0098] The tap selector 2000 of Comparative Example 2 includes an open / close drive cam portion 2001 formed integrally with a current collecting portion 2002. The open / close drive cam portion 2001 is arranged concentrically around the central axis of the tap selector 2000. The open / close drive cam portion 2001 causes the movable contact assembly 2003 to enter an open state when switching the tap, and moves away from the fixed contact 2004. At the end of movement (stop position), the movable contact assembly 2003 enters a closed state and comes into contact with the fixed contact 2004. As a result, Comparative Example 2 is configured to conduct electricity at the end of movement (stop position).

[0099] However, in the configuration of Comparative Example 2, contact with the current collecting portion 2002 continues during switching operation, making it difficult to resolve the problems of durability and load, as well as the current carrying capacity limit of the roller contact.

[0100] Next, Comparative Example 3 will be described. Fig. 37 is a cross-sectional view of the tap selector 3000 of Comparative Example 3. Fig. 38 is a configuration diagram of the movable contact portion of Comparative Example 3. Fig. 39 is an exploded perspective view of the tap selector 3000 of Comparative Example 3.

[0101] The tap selector 3000 of Comparative Example 3 includes a conductive contact piece 3002 incorporated into an open / close movable contact assembly 3001. The conductive contact piece 3002 opens during a tap change operation and separates from the current collecting ring portion 3003 and the fixed contact portion 3004. The conductive contact piece 3002 is configured to close after the tap change and return to a conductive state. Because there is no rolling contact between the contacts, the conductive contact piece 3002 has a rectangular cross section. This can eliminate problems with current carrying capacity and concerns about the wear resistance of the current collecting ring portion 3003.

[0102] However, the configuration of Comparative Example 3 requires two movable contact switching Geneva switches 3005 and a complex movable contact switching mechanism 3006. These additional mechanical parts increase component costs and assembly costs, affect durability due to the complex structure, and increase the size of the tap selector 3000. In other words, the above-mentioned additional mechanical parts are contrary to the required specifications that will be required for future on-load tap changers.

[0103] In contrast, the tap selector 2 of this embodiment includes a movable contact assembly 50 that operates in conjunction with the rotational movement of the Geneva gear. The movable contact assembly 50 includes a drive slider 51, a lifting arm 60, and a movable contact 70. Guide grooves 31 are formed on the outer side (top and bottom surfaces) of the contact portion of the current collecting ring 30. The drive slider 51 slides radially via drive rollers 52 that engage with the guide grooves 31. A lifting pressure portion 56 is integrally formed with the drive slider 51. The lifting arm 60 is provided to correspond to the inner peripheral portion (current collecting ring 30 side) and outer peripheral portion (fixed ring 35 side) of the drive slider 51. A lifting roller 61 is attached to the lifting arm 60. The lifting roller 61 is pressed against the lifting pressure portion 56 by the sliding movement of the drive slider 51, causing the lifting arm 60 to rotate. The movable contact 70 short-circuits between the inner collector ring 30 and the outer fixed contact 36. The planar movement of the movable contact 70 is restricted by the lift arm 60. A biasing member 75 is provided between the movable contact 70 and the cover 80. The biasing member 75 biases the movable contact 70 against the lift arm 60. Rotation of the lift arm 60 simultaneously raises and lowers both ends of the movable contact 70, thereby performing contact-opening and contact-closing operations. The lift arm 60 is rotatably supported relative to the cover 80. The cover 80 is supported by the drive support column 40 via a holder. Horizontal guide rollers 53 are attached to the four planar corners of the drive slider 51. The drive slider 51 is supported by the horizontal guide rollers 53 so that it can slide against the inner wall surfaces on both sides of the cover 80. Vertical guide rollers 54A, 54B are attached to the inner periphery (current collecting ring 30 side) and outer periphery (fixed ring 35 side) of the drive slider 51. The drive slider 51 rotates around a reference axis G while its movement in the height direction relative to the current collecting ring 30 and the fixed ring 35 is restricted by the vertical guide rollers 54A, 54B. The components of the movable contact assembly 50 are arranged in a pair, one above the other. The movable contact assembly 50 is configured so that a pair of multiple movable contacts 70, which are supported so as to be able to move up and down, sandwich the current collecting ring 30 and the fixed ring 35 (the fixed contact 36 attached to the fixed ring 35). When the Geneva mechanism of the tap selector 2 is driven, the movable contact assembly 50 rotates around the reference axis G via the drive support 40.Then, the drive slider 51 slides radially along the guide groove 31 of the current collecting ring 30. When the movable contact assembly 50 moves, both the contacts on the current collecting ring 30 side and the fixed ring 35 side are opened. When the movable contact assembly 50 is stopped, both the contacts are closed.

[0104] According to this embodiment, the above operation can be achieved without rolling or sliding contact by a simple mechanism provided in the movable contact assembly 50. Therefore, it is possible to provide an inexpensive movable contact drive mechanism 100 for the tap selector 2 that is highly durable and has a small load during switching.

[0105] During contact opening, a reaction force to the contact biasing force acts between the guide groove 31 of the current collecting ring 30 and the drive roller 52. This point of action is located radially inward of the movable contact assembly 50, at a relatively small distance from the center. This allows the drive load torque during contact opening to be kept low. In addition, after the movable contact 70 opens, the pair of upper and lower drive sliders 51 abut at their centers, thereby canceling out the contact opening reaction force. This allows the switching drive load after contact opening to be kept extremely small.

[0106] Next, a modification of the embodiment will be described. The movable contact assembly of the embodiment includes a drive roller that is rotatably supported on the drive slider and guided by the guide groove. However, the movable contact assembly does not necessarily have to include a drive roller. For example, the drive slider may have a spherical convex portion (e.g., a curved portion) that is guided by the guide groove. For example, the installation mode of the drive roller can be changed depending on the design specifications.

[0107] The constricted portion of the embodiment is curved radially inward relative to the constant radius when viewed axially. Alternatively, the constricted portion may be curved radially outward relative to the constant radius when viewed axially. For example, the configuration of the constricted portion can be varied depending on the design specifications.

[0108] The drive support in the embodiment simultaneously rotates and drives the multiple movable contact assemblies. Alternatively, the movable contact drive mechanism may include separate drive members corresponding to the multiple movable contacts. For example, the drive mode of the multiple movable contact assemblies can be changed according to design specifications.

[0109] The movable contact assembly of the embodiment is assembled by stacking components of the same type in the movable contact assembly upside down in order on both sides of the current collecting ring and the fixed ring in the axial direction. Alternatively, the movable contact assembly may be assembled by stacking components of different types on both sides of the current collecting ring and the fixed ring in the axial direction. For example, the configuration of the movable contact assembly can be changed according to design specifications.

[0110] In the embodiment, the pair of drive sliders have abutment portions that abut against each other so as to cancel out the open electrode holding force. However, the pair of drive sliders do not necessarily have to have abutment portions. For example, the installation mode of the members for canceling out the open electrode holding force can be changed depending on the design specifications.

[0111] The movable contact assembly of the embodiment further includes a guide holder that guides the abutment portion of the drive slider along the axial direction. However, the movable contact assembly does not necessarily have to include the guide holder. For example, the installation mode of the guide holder can be changed depending on the design specifications.

[0112] The movable contact assembly of the embodiment further includes a cover that covers the drive slider, the lift arm, and the movable contact. However, the movable contact assembly does not necessarily have to include a cover. For example, the installation mode of the cover can be changed according to the design specifications.

[0113] The movable contact assembly of the embodiment further includes a plurality of horizontal guide rollers that are rotatably supported on the drive slider and guide the radial sliding movement of the drive slider along the inner wall surface of the cover. However, the movable contact assembly does not necessarily have to include the horizontal guide rollers. For example, the installation mode of the horizontal guide rollers can be changed depending on the design specifications.

[0114] The movable contact assembly of the embodiment further includes a plurality of vertical guide rollers that are rotatably supported on the drive slider and that are in rolling contact with the surfaces of the current collecting ring and the fixed ring. However, the movable contact assembly does not necessarily have to include the vertical guide rollers. For example, the installation mode of the vertical guide rollers can be changed depending on the design specifications.

[0115] In the embodiment, a total of four horizontal guide rollers are arranged, one at each of the four corners of the drive slider when viewed from the axial direction. However, the horizontal guide rollers may be arranged at locations other than the four corners of the drive slider. For example, the number of horizontal guide rollers may be three or less or five or more. For example, the arrangement locations and number of horizontal guide rollers can be changed depending on design specifications.

[0116] In the embodiment, two vertical guide rollers are disposed on the drive slider, one facing the current collecting ring and the other facing the fixed ring. However, the vertical guide rollers may be disposed at locations on the drive slider other than those facing the current collecting ring and the fixed ring. For example, the number of vertical guide rollers may be one or three or more. For example, the location and number of vertical guide rollers may be changed depending on the design specifications.

[0117] The drive slider of the embodiment includes a lift pressing portion that rotates the lift arm by contacting the lift roller with the sliding movement of the drive slider. However, the drive slider does not necessarily have to include a lift pressing portion. For example, a member for rotating the lift arm may be provided separately from the drive slider. For example, the installation mode of the lift pressing portion can be changed according to design specifications.

[0118] In the embodiment, a plurality of movable contacts are provided. However, only one movable contact may be provided. For example, the installation mode of the movable contact can be changed according to the design specifications.

[0119] The lifting arm of the embodiment includes multiple arm protrusions that simultaneously raise and lower multiple movable contacts. However, the lifting arm does not necessarily have to include arm protrusions. For example, a separate member may be provided to raise and lower the multiple movable contacts. For example, the installation mode of the arm protrusions can be changed depending on the design specifications.

[0120] The lifting arm of the embodiment includes a plurality of partitions that separate the movable contacts. However, the lifting arm does not necessarily need to include partitions. For example, a separate member may be provided to lift and lower the plurality of movable contacts without contacting each other. For example, the installation mode of the partitions can be changed according to the design specifications.

[0121] In the embodiment, the plurality of partitions are spaced apart from one another so that the movable contacts can move obliquely relative to the circumferential direction when the movable contact assembly rotates in the circumferential direction. Alternatively, the plurality of partitions may be arranged so that the movable contacts cannot move obliquely. For example, the plurality of partitions may be spaced apart from one another by approximately the same distance as the thickness of the movable contacts. For example, the arrangement of the plurality of partitions can be changed depending on the design specifications.

[0122] The movable contact of the embodiment includes a central protrusion that protrudes from the radial center of the movable contact so as to be sandwiched between a pair of lifting arms. However, the movable contact does not necessarily have to include a central protrusion. For example, the position of the movable contact may be limited by a portion other than the central protrusion. For example, the placement of the central protrusion can be changed depending on the design specifications.

[0123] The movable contact of the embodiment has a central recess in which a biasing member is disposed, at a position overlapping with the central protrusion when viewed from the axial direction. However, the movable contact does not necessarily have to have a central recess. For example, the biasing member may be disposed in a portion of the movable contact other than the central recess. For example, the arrangement of the central recess can be changed depending on the design specifications.

[0124] The movable contact assembly of the embodiment further includes a biasing member that biases the movable contact. However, the movable contact assembly does not necessarily have to include a biasing member. For example, the movable contact may include a member, mechanism, device, etc. that applies a force to the movable contact, separate from the biasing member. For example, the installation mode of the biasing member can be changed depending on the design specifications.

[0125] The reference member in the embodiment is a Geneva gear that rotates in conjunction with the rotation of the Geneva driver. However, the reference member does not have to be a Geneva gear. For example, the reference member may be a rotating body that rotates when driven by a drive motor. For example, the reference member may be any member that can rotate around a reference axis. For example, the form of the reference member can be changed depending on the design specifications.

[0126] According to at least one of the embodiments described above, the switching operation between rotation stop and rotation drive of the movable contact assembly is performed in a non-contact state, which reduces the load during switching, improves durability, and prevents an increase in the number of parts.

[0127] Although several embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, as well as within the scope of the invention described in the claims and their equivalents. [Explanation of symbols]

[0128] 2...tap selector, 30...current-carrying ring, 31...guide groove, 32...steady radius portion, 33...constricted portion, 35...fixed ring, 36...fixed contact, 40...drive support, 50...movable contact assembly, 51...drive slider, 52...drive roller, 53...horizontal guide roller, 54A, 54B...vertical guide roller, 56...lifting / lowering pressure portion, 57...contact portion, 58...guide holder, 60...lifting / lowering arm, 61...lifting / lowering roller, 64...arm protrusion, 65...partition portion, 70...movable contact, 72...central convex portion, 73...central concave portion, 75...biasing member, 80...cover, 100...movable contact drive mechanism, G...reference axis, CS...contact state, NC...contact non-contact state

Claims

1. a movable contact assembly that rotates in a circumferential direction around a reference axis; The movable contact assembly includes: a drive slider that slides in a radial direction perpendicular to an axial direction along the reference axis; a lifting arm that rotates in conjunction with the sliding movement of the drive slider; a movable contact that moves in conjunction with the rotational movement of the lifting arm, and maintains a contact state between the current collecting ring and the fixed contact when the rotation of the movable contact assembly is stopped, and maintains a contactless state between the current collecting ring and the fixed contact when the movable contact assembly is rotationally driven, The switching operation between rotation stop and rotation drive of the movable contact assembly is performed in a non-contact state of the contacts. Tap selector moving contact drive mechanism.

2. the current collecting ring has a guide groove formed concentrically with the reference axis, The movable contact assembly includes: a drive roller rotatably supported by the drive slider and guided by the guide groove; a cover that covers the drive slider, the lifting arm, and the movable contact; a biasing member disposed between the cover and the movable contact and biasing the movable contact, The movable contact drive mechanism for a tap selector according to claim 1.

3. The guide groove is a constant radius portion that guides the drive roller in the circumferential direction at a fixed position in the radial direction; a constricted portion that guides the drive roller in a direction intersecting the circumferential direction, The constricted portion curves radially inward relative to the constant radius portion when viewed in the axial direction.

3. The movable contact drive mechanism for a tap selector according to claim 2.

4. The movable contact assemblies are arranged in plurality along the axial direction, The movable contact drive mechanism further includes a drive support column extending along the axial direction and supporting the plurality of movable contact assemblies to rotate them in the circumferential direction.

4. The movable contact drive mechanism for a tap selector according to claim 2 or 3.

5. the movable contact drive mechanism further includes a fixed ring formed concentrically around the reference axis and supporting the fixed contact; The movable contact assembly is assembled by stacking components of the same type in the movable contact assembly upside down in order on both sides of the current collecting ring and the fixing ring in the axial direction.

3. A movable contact drive mechanism for a tap selector according to claim 1 or 2.

6. the drive sliders are provided as a pair facing each other in the axial direction, and are configured such that an open-contact holding force that maintains the contact non-contact state between the current collecting ring and the fixed contact acts in the axial direction; The pair of drive sliders have abutment portions that abut against each other so as to cancel out the open-pole holding force.

3. A movable contact drive mechanism for a tap selector according to claim 1 or 2.

7. The movable contact assembly further includes a guide holder that guides the contact portion of the drive slider along the axial direction. The movable contact drive mechanism for a tap selector according to claim 6.

8. the movable contact drive mechanism further includes a fixed ring formed concentrically around the reference axis and supporting the fixed contact; The movable contact assembly includes: a cover that covers the drive slider, the lifting arm, and the movable contact; a plurality of horizontal guide rollers that are rotatably supported relative to the drive slider and guide the sliding movement of the drive slider in the radial direction along the inner wall surface of the cover; a plurality of vertical guide rollers rotatably supported relative to the drive slider and in rolling contact with the surfaces of the current collecting ring and the fixed ring, 3. A movable contact drive mechanism for a tap selector according to claim 1 or 2.

9. The drive slider is formed in a rectangular shape when viewed from the axial direction, The horizontal guide rollers are arranged at four corners of the drive slider when viewed from the axial direction, and a total of four horizontal guide rollers are arranged at four corners of the drive slider when viewed from the axial direction. a total of two vertical guide rollers are disposed on the drive slider, one at a portion facing the current collecting ring and the other at a portion facing the fixed ring; The movable contact drive mechanism for a tap selector according to claim 8.

10. The movable contact assembly includes: a cover that covers the drive slider, the lifting arm, and the movable contact and rotatably supports the lifting arm; a lifting roller rotatably supported on the lifting arm, the drive slider includes a lifting / lowering pressing portion that rotates the lifting arm by contacting the lifting roller with a sliding movement of the drive slider; 3. A movable contact drive mechanism for a tap selector according to claim 1 or 2.

11. The movable contact is provided in plurality, The lifting arm is a plurality of arm protrusions that simultaneously raise and lower the plurality of movable contacts; and a plurality of partition portions that partition the movable contact.

3. A movable contact drive mechanism for a tap selector according to claim 1 or 2.

12. the plurality of partition portions are arranged at intervals from one another so that the movable contact can move in a direction oblique to the circumferential direction when the movable contact assembly rotates in the circumferential direction. The movable contact drive mechanism of the tap selector according to claim 11.

13. The lifting arms are provided as a pair facing each other in the radial direction, the movable contact includes a central protrusion protruding from a central portion of the movable contact in the radial direction so as to be sandwiched between the pair of lifting arms; 3. A movable contact drive mechanism for a tap selector according to claim 1 or 2.

14. The movable contact assembly further includes a biasing member that biases the movable contact, The movable contact has a central recess in which the biasing member is disposed, at a position overlapping the central protrusion when viewed from the axial direction. The movable contact drive mechanism for a tap selector according to claim 13.

Citation Information

Patent Citations

  • Moving contact for tap switch

    CN101383233A

  • On-load tap changer

    JP1987263620A

  • Semiconductor integrated circuit device

    JP1994052688A

  • On-load tap changer

    JP2016021533A

  • Torque adjusting device and tap switching device

    JP2019212821A