WO2020152775A1

WO2020152775A1 - Limit tap restricting device, and electric operating device for load tap changer

Info

Publication number: WO2020152775A1
Application number: PCT/JP2019/001846
Authority: WO
Inventors: 江口　直紀; 拓石川
Original assignee: 株式会社東芝; 東芝エネルギーシステムズ株式会社
Priority date: 2019-01-22
Filing date: 2019-01-22
Publication date: 2020-07-30
Also published as: JP7021374B2; JPWO2020152775A1

Abstract

A limit tap restricting device of an embodiment comprises a feed screw mechanism, a block, and a rotation stopping unit. The feed screw mechanism includes a feed screw shaft which rotates in conjunction with a main drive shaft. The main drive shaft is disposed in a torque transmission path from a motor to a load tap changer. The block is moved by the feed screw mechanism in an axial direction of the feed screw shaft. The rotation stopping unit can be abutted against the block at a position in the axial direction corresponding to a limit tap of the load tap changer, and stop rotation of the main drive shaft.

Description

Electric control device for limit tap limiter and tap changer under load

The embodiment of the present invention relates to an electric operating device for a limit tap limiting device and a load tap changer.

The load tap changer is a device that adjusts the voltage by changing the turns ratio (transformation ratio) of the transformer in an operating state. The electric operating device of the load tap changer performs the switching operation of the load tap changer by rotating the main shaft by the motor. The electric operating device detects the rotational position of the driving shaft and grasps the tap position of the tap changer under load. When the load tap changer reaches the extreme tap position, the electrically operated device electrically stops rotation of the drive shaft. The electric operating device has an extreme tap limiting device. The limit tap limiting device mechanically stops the rotation of the driving shaft when the electric rotation stopping of the driving shaft does not function.
The extreme tap limiting device is required to be downsized.

Japanese Patent Publication No. 58-4808

The problem to be solved by the present invention is to provide an electric operation device for an extreme tap limiting device and a load tap changer that can be downsized.

The limit tap limiting device of the embodiment has a feed screw mechanism, a top, and a rotation stop unit. The feed screw mechanism includes a feed screw shaft that rotates in conjunction with the driving shaft. The drive shaft is arranged in a torque transmission path from the motor to the load tap changer. The top moves in the axial direction of the feed screw shaft by the feed screw mechanism. The rotation stopping unit can stop the rotation of the driving shaft by contacting the top at the axial position corresponding to the limit tap position of the load tap changer.

The perspective view of the electric operating device of the tap changer under load of the embodiment. The perspective view of a drive mechanism part. The perspective view of the extreme tap limiting device of an embodiment. The perspective view of the feed screw nut part. FIG. 5 is a sectional view of a top taken along line F5-F5 of FIG. The perspective view of an arm slider part. Sectional drawing of the arm slider part in the F7-F7 line of FIG. The 1st operation explanatory view of the extreme tap limiting device of an embodiment. The 2nd operation|movement explanatory drawing of the extreme tap limiting device of embodiment. The 3rd operation|movement explanatory drawing of the extreme tap limiting device of embodiment.

Hereinafter, the limit tap limiting device and the electric operating device for the load tap changer of the embodiment will be described with reference to the drawings.
FIG. 1 is a perspective view of an electric operating device for a load tap changer according to an embodiment. The load tap changer LTC is a device that adjusts the voltage by changing the turns ratio (transformation ratio) of the transformer in the operating state. The electric operating device 1 switches the tap position of the load tap changer LTC between the high position side (step-up side) and the low position side (step-down side). The electric operating device 1 rotates the main shaft 10 to switch the tap switch during load LTC via a transmission shaft (not shown). The electric operating device 1 includes a housing 1 a, a drive mechanism unit 2, and a control board unit 3. The housing 1 a houses the drive mechanism section 2 and the control board section 3. The control board unit 3 controls the operation of the drive mechanism unit 2.

FIG. 2 is a perspective view of the drive mechanism section. In the present application, the X direction, Y direction and Z direction of the Cartesian coordinate system are defined as follows. The Z direction is the axial direction of the driving shaft 10. The +Z direction is a direction from the drive shaft second pulley 23 toward the drive shaft first pulley 13. The X direction is the axial direction of the feed screw shaft 32. The +X direction is the direction in which the feed screw nut 42 (see FIG. 4) advances along the feed screw shaft 32 when the load tap changer LTC (see FIG. 1) is switched from the low position side tap to the high position side tap. The Y direction is a direction perpendicular to the X and Z directions. The +Y direction is a direction from the feed screw shaft 32 toward the driving shaft 10. For example, the Z direction is the vertical direction, and the X direction and the Y direction are the horizontal directions.

The drive mechanism unit 2 includes a motor 5, a main shaft 10, a torque limiter 12, a rotation detector 18, and an extreme tap limiting device 15.
The rotation axis of the motor 5 is arranged parallel to the Z direction. A motor pulley 6 is attached to the rotating shaft of the motor 5.

The driving shaft 10 is arranged in the torque transmission path from the motor 5 to the load tap changer LTC (see FIG. 1). The drive shaft 10 is arranged in the −Y direction of the motor 5. The axial direction of the driving shaft 10 is arranged parallel to the Z direction. The driving shaft first pulley 13 is mounted in the +Z direction of the driving shaft 10. A first timing belt 8 is stretched between the drive shaft first pulley 13 and the motor pulley 6. Torque can be transmitted from the motor 5 to the drive shaft 10 via the motor pulley 6, the first timing belt 8 and the drive shaft first pulley 13. By using the first timing belt 8, lubrication of the torque transmission path becomes unnecessary.

The torque limiter 12 limits the transmission torque between the outer peripheral side and the inner peripheral side to a predetermined torque or less. The outer peripheral side (input side) of the torque limiter 12 is connected to the drive shaft first pulley 13. The inner peripheral side (output side) of the torque limiter 12 is connected to the drive shaft 10. As will be described later, the limit tap limiting device 15 can stop the rotation of the driving shaft 10. When the extreme tap limiting device 15 stops the rotation of the driving shaft 10, the torque transmitted from the motor 5 to the driving shaft 10 is limited to a predetermined torque.

The rotation detector 18 is arranged at the end of the drive shaft 10 in the −Z direction. The rotation detector 18 is a multi-rotation absolute position detection type rotation detector (multi-rotation encoder). The multi-rotation encoder has a multi-rotation member that rotates n (n>1) times with respect to the main axis. The multi-rotation encoder accurately detects the rotation position of the driving shaft 10 by detecting the rotation position of the multi-rotation member. The rotation detector 18 outputs a signal corresponding to the rotational position of the driving shaft 10 to the control board unit 3 (see FIG. 1).

The control board unit 3 shown in FIG. 1 grasps the tap position of the load tap changer LTC based on the rotational position of the driving shaft 10. When the load tap changer LTC reaches the limit tap position, the control board unit 3 outputs an electric signal to stop the motor 5. That is, the electric operating device 1 electrically stops the rotation of the driving shaft 10. When the rotation detector 18, the control board unit 3 or the motor 5 fails, the electrical rotation stop of the drive shaft 10 does not function. The limit tap limiting device 15 mechanically stops the rotation of the driving shaft 10 when the rotation stop of the electric driving shaft 10 does not function electrically.

The extreme tap limiting device 15 is arranged as a unit in the −Y direction of the driving shaft 10 as shown in FIG. The limit tap limiting device 15 has a pair of

frames

16, 16. The components of the extreme tap limiting device 15 are directly or indirectly supported by the pair of

frames

16, 16. The pair of

frames

16, 16 are fixed to the casing 1a of the electric operating device 1 shown in FIG.

FIG. 3 is a perspective view of the extreme tap limiting device of the embodiment. The extreme tap limiting device 15 includes a power transmission unit 20, a feed screw shaft portion 30, a feed screw nut portion 40, and a rotation stop unit 15a. The rotation stop unit 15a has an arm slider section 50 and a rotation stop mechanism 15b. The rotation stop mechanism 15b has a stopper holding mechanism 15c, a stopper 100, and a stopper receiver 110. The stopper holding mechanism 15c has a relay arm 70, a first arm 80, and a second arm 90.

The power transmission unit 20 includes a main drive shaft second pulley 23, a worm shaft 28, a worm pulley 25, and a second timing belt 24.
The drive shaft second pulley 23 is attached to the drive shaft 10. The driving shaft second pulley 23 is arranged in the −Z direction of the driving shaft first pulley 13 (see FIG. 2).
The worm shaft 28 is arranged in the −Y direction of the drive shaft 10. The axial direction of the worm shaft 28 is arranged parallel to the Z direction. The worm shaft 28 has a worm 29 at the end in the −Z direction.
The worm pulley 25 is mounted on the worm shaft 28 in the +Z direction.

The second timing belt 24 is stretched between the drive shaft second pulley 23 and the worm pulley 25. Torque is transmitted from the drive shaft 10 to the worm shaft 28 via the drive shaft second pulley 23, the second timing belt 24, and the worm pulley 25. The worm shaft 28 rotates as the drive shaft 10 rotates. By using the second timing belt 24, lubrication of the torque transmission path becomes unnecessary.

The feed screw shaft portion 30 includes a feed screw shaft 32 and a worm wheel 34.
The feed screw shaft 32 is arranged in the −Y direction of the worm shaft 28. The axial direction of the feed screw shaft 32 is arranged parallel to the X direction. The feed screw shaft 32 has a feed screw 36 in a region in the −X direction. The feed screw 36 is a male screw formed on the outer peripheral surface of the feed screw shaft 32. The length of the feed screw 36 is at least half the length of the feed screw shaft 32. A pair of

bearings

31a and 31b are arranged at both ends of the feed screw 36 in the X direction. The pair of

bearings

31a and 31b support the feed screw shaft 32.
The worm wheel 34 is mounted near the end of the feed screw shaft 32 in the +X direction. The worm wheel 34 meshes with the worm 29 of the worm shaft 28. The feed screw shaft 32 rotates as the worm shaft 28 rotates.

FIG. 4 is a perspective view of the feed screw nut portion. The feed screw nut portion 40 includes a feed screw nut 42, a piece support plate 44 (44a, 44b), and a piece 48 (48a, 48b). The feed screw shaft 32 of the feed screw shaft portion 30 and the feed screw nut 42 of the feed screw nut portion 40 form a feed screw mechanism 40a.

The feed screw nut 42 has a female screw that meshes with the feed screw 36 of the feed screw shaft 32. The feed screw nut 42 has a through hole in the +Z direction of the female screw. The through hole penetrates the feed screw nut 42 in the X direction. The rotation restricting shaft 37 is inserted into the through hole. The rotation restricting shaft 37 is arranged in parallel with the feed screw shaft 32. Both ends of the rotation restricting shaft 37 in the X direction are fixed to the pair of

bearings

31a and 31b. The rotation restricting shaft 37 restricts the rotation of the feed screw nut 42 in the circumferential direction of the feed screw shaft 32. As a result, when the feed screw shaft 32 rotates, the feed screw nut 42 moves in the X direction.

When switching the tap position of the load tap changer LTC to the high position side, the drive shaft 10 rotates counterclockwise in the -Z direction. At this time, the feed screw shaft 32 rotates counterclockwise in the −X direction, and the feed screw nut 42 moves in the +X direction. That is, the +X direction of the feed screw nut portion 40 corresponds to the higher position side of the load tap changer LTC. On the contrary, the −X direction of the feed screw nut portion 40 corresponds to the low side of the tap changer LTC under load.

The top support plate 44 (44a, 44b) is fixed to the feed screw nut 42. The top support plate 44 is arranged in the −Y direction of the feed screw nut 42. The top support plate 44 is arranged parallel to the XZ plane. The top support plate 44 includes a high-side support plate 44a and a low-side support plate 44b.

The high-level side support plate 44a is arranged in the +X direction of the feed screw nut 42. The high-side support plate 44a has a top position adjustment hole 45a that penetrates the high-side support plate 44a in the Y direction. The top position adjusting hole 45a is formed in an oval shape extending in the X direction.
The lower support plate 44b is arranged in the −X direction of the feed screw nut 42. The lower support plate 44b has a top position adjusting hole 45b similar to the top position adjusting hole 45a.

The tops 48 (48a, 48b) are arranged in the −Y direction of the top support plate 44. The top 48 is formed in a rectangular shape when viewed from the Y direction. The top (pressing top) 48 includes a high-side top 48a and a low-side top 48b.
The high position side piece 48a is formed in a cubic shape. The +X direction surface of the high-side piece 48a is parallel to the YZ plane and comes into contact with a piece receiving portion of the high-side arm, which will be described later.
The lower-side piece 48b is formed similarly to the higher-side piece 48a.

FIG. 5 is a cross-sectional view of the frame taken along the line F5-F5 of FIG. The high-side piece 48a has a mounting shaft 46a protruding in the +Y direction. The mounting shaft 46a is inserted into the top position adjusting hole 45a and projects in the +Y direction of the high-level side support plate 44a. The base end of the mounting shaft 46a is arranged inside the top position adjusting hole 45a. The cross section of the base end portion of the mounting shaft 46a is formed in a rectangular shape. A male screw is formed on the outer periphery of the mounting shaft 46a protruding in the +Y direction of the high-level side support plate 44a. A top fixing nut 47a is arranged in the +Y direction of the high-side support plate 44a. The top fixing nut 47a is attached to the male screw of the mounting shaft 46a. As a result, the high-side piece 48a is fixed to the high-side support plate 44a.

The position of the high-order piece 48a in the X direction is adjusted as follows. When the load tap changer LTC reaches the high-side limit tap position, the high-side piece 48a moves in the +X direction and contacts the piece receiving portion 68a of the high-side arm 60a. The high-order side arm 60a abuts on the frame receiving portion 68a in a state in which the engagement protrusion 88 of the first arm 80 and the engagement recess 93 of the second arm 90, which will be described later, are engaged. In order to realize this contact, the high position side piece 48a is arranged at a predetermined position in the X direction. The position of the high-side piece 48a in the X direction can be changed along the piece position adjusting hole 45a. The high-side piece 48a is fixed to the high-side support plate 44a at a predetermined position in the X direction.

Like the high-side piece 48a, the low-side piece 48b has a mounting shaft 46b. The lower piece 48b is fixed to the lower support plate 44b by a piece fixing nut 47b.
When the load tap changer LTC reaches the low-side limit tap position, the low-side top 48b moves in the -X direction and contacts the top receiving portion 68b of the low-side arm 60b. The lower-side piece 48b is arranged at a predetermined position in the X direction so that this contact is realized.

As shown in FIG. 3, the rotation stop unit 15a can stop the rotation of the driving shaft 10 by contacting the tops 48a and 48b at a position in the X direction corresponding to the extreme tap position. The rotation stop unit 15a has an arm slider section 50 and a rotation stop mechanism 15b.

FIG. 6 is a perspective view of the arm slider portion. The arm slider unit 50 includes a substrate 52, a slider 56, a high-ranking arm 60a, and a low-ranking arm 60b.
The board 52 is arranged in the −Y direction of the feed screw nut portion 40. The substrate 52 is arranged parallel to the XY plane. The substrate 52 is formed in a long plate shape whose longitudinal direction is the X direction.

The slider 56 is arranged on the surface of the substrate 52 in the +Z direction. The slider 56 is arranged at the center of the substrate 52 in the X direction. A slit 53 penetrating the substrate 52 in the Z direction is formed at the center of the substrate 52 in the X direction. The slit 53 is formed in an oval shape extending in the Y direction.

FIG. 7 is a cross-sectional view of the arm slider portion taken along the line F7-F7 in FIG. The slider 56 has a pair of guide pins 57, 57. The pair of guide pins 57, 57 are arranged apart from each other in the Y direction. The pair of guide pins 57, 57 penetrates the slit 53 from the −Z direction of the substrate 52 and is fixed to the slider 56. By moving the pair of guide pins 57, 57 along the slit 53, the slider 56 can move in the Y direction. The slider 56 has a slider hole 59 that penetrates the slider 56 in the Z direction. The slider hole 59 is formed in a rectangular shape extending in the Y direction. A first protrusion 72 of a relay arm 70, which will be described later, is inserted into the slider hole 59.

The high arm 60a is arranged in the +Z direction of the substrate 52 and the slider 56, as shown in FIG. The higher arm 60a is formed in an L shape when viewed from the Z direction. The higher arm 60a has a long arm 62a extending in the X direction and a short arm 67a extending in the Y direction. The long arm 62a is arranged along the edge of the substrate 52 in the −Y direction. The short arm 67a is arranged along the edge of the substrate 52 in the +X direction. The +X direction end of the long arm 62a and the −Y direction end of the short arm 67a are the bent portions of the high-order side arm 60a. An arm pin 61 is arranged at the bent portion of the higher arm 60a. The arm pins 61a are fixed to the corners of the substrate 52 in the +X direction and the −Y direction. The higher arm 60a is rotatable about an arm pin 61a extending in the Z direction.

An arm hole 63a penetrating the long arm 62a in the Z direction is formed at the −X direction end of the long arm 62a. The arm hole 63a is formed in an oval shape extending in the X direction. As shown in FIG. 7, a slider pin 58 is arranged in the +Z direction of the slider 56. The slider pin 58 is arranged parallel to the Z direction. The slider pin 58 is fixed to the −Y direction guide pin 57 of the slider 56. The slider pin 58 is arranged inside the arm hole 63a of the long arm 62a.

As shown in FIG. 6, a piece receiving portion 68a is formed at the end of the short arm 67a in the +Y direction. The frame receiving portion 68a is a rectangular notch formed at a corner of the short arm 67a in the +Y direction and the −X direction. The surface of the top receiving portion 68a in the −X direction is parallel to the YZ plane and abuts on the surface of the high-side piece 48a in the +X direction.

▽The top frame 48a pushes the frame receiving portion 68a in the +X direction. The higher arm 60a rotates clockwise around the arm pin 61a in the -Z direction. The higher arm 60a pushes the slider pin 58 arranged in the arm hole 63a in the +Y direction. As a result, the slider 56 moves in the +Y direction. Here, the length of the long arm 62a in the X direction is longer than the length of the short arm 67a in the Y direction. The amount of movement of the arm hole 63a in the +Y direction is larger than the amount of movement of the top receiving portion 68a in the +X direction. As a result, the amount of movement of the slider 56 in the +Y direction is amplified with respect to the amount of movement of the high-side frame in the +X direction.

The lower arm 60b is formed substantially symmetrically with respect to the upper arm 60a with the YZ plane located at the center of the substrate 52 in the X direction as a plane of symmetry. However, at the position of the slider pin 58, the end in the −X direction of the high-side arm 60a is arranged offset in the +Z direction, and the end in the +X direction of the low-side arm 60b is arranged offset in the −Z direction. It This avoids interference between the high-ranking arm 60a and the low-ranking arm 60b.

The lower-side piece 48b pushes the piece receiving portion 68b of the lower-side arm 60b in the -X direction. The lower arm 60b rotates counterclockwise in the −Z direction about the arm pin 61b. The lower arm 60b pushes the slider pin 58 arranged in the arm hole 63b (see FIG. 7) in the +Y direction. As a result, the slider 56 moves in the +Y direction.

As shown in FIG. 3, the rotation stop mechanism 15b can stop the rotation of the driving shaft 10 by sliding the slider 56. The rotation stop mechanism 15b has a stopper holding mechanism 15c, a stopper 100, and a stopper receiver 110. The stopper holding mechanism 15c can hold the stopper 100 in the retracted position and release the holding by sliding the slider 56. The stopper holding mechanism 15c has a relay arm 70, a first arm 80, and a second arm 90.

The relay arm 70 is arranged in the +Z direction of the arm slider section 50, as shown in FIG. The relay arm 70 is formed in a long plate shape extending in the Z direction, and is arranged parallel to the YZ plane. An arm pin 71 is arranged in the −Z direction from the center of the relay arm 70 in the Z direction. The relay arm 70 is rotatable around an arm pin 71 extending in the X direction. The relay arm 70 has a first protrusion 72 at the end in the −Z direction. The first protrusion 72 is inserted into a slider hole 59 formed in the slider 56. The relay arm 70 has a second protrusion 78 at the end in the +Z direction. The second protrusion 78 is inserted into the first arm hole 83 of the first arm 80 described later.

When the slider 56 moves in the +Y direction, the slider hole 59 pushes the first protrusion 72 in the +Y direction. The relay arm 70 rotates counterclockwise around the arm pin 71 in the −X direction. The second protrusion 78 pushes the first arm hole 83 in the −Y direction. Here, the length from the arm pin 71 to the second protrusion 78 is longer than the length from the arm pin 71 to the first protrusion 72. The amount of movement of the second protrusion 78 in the −Y direction is larger than the amount of movement of the first protrusion 72 in the +Y direction. As a result, the amount of movement of the first arm 80 in the −Y direction is amplified with respect to the amount of movement of the slider 56 in the +Y direction.

The first arm 80 is arranged in the +Z direction of the relay arm 70, as shown in FIG. The first arm 80 is formed in an L shape when viewed from the Z direction. The first arm 80 has a short arm 82 extending in the X direction and a long arm 87 extending in the Y direction. The +X direction end of the short arm 82 and the −Y direction end of the long arm 87 are the bent portions of the first arm 80. An arm pin 81 is arranged at the bent portion of the first arm 80. The first arm 80 is rotatable around an arm pin 81 extending in the Z direction.

A first arm hole 83 that penetrates the short arm 82 in the Z direction is formed at the −X direction end of the short arm 82. The first arm hole 83 is formed in a rectangular shape extending in the Y direction. The second protrusion 78 of the relay arm 70 is inserted into the first arm hole 83.
An engagement protrusion 88 is formed at the end of the long arm 87 in the +Y direction. The engagement protrusion 88 is formed in a taper shape in the +Y direction. The engagement protrusion 88 is formed by extending the corners of the long arm 87 in the +X direction and the +Y direction in the +Y direction from the corners of the −X direction and the +Y direction. An end side of the engagement protrusion 88 in the +Y direction is a straight line inclined with respect to the X direction. The engagement protrusion 88 engages with an engagement recess 93 of the second arm 90 described later.

A spring 84, which is an elastic member, is arranged in the +X direction of the long arm 87. The spring 84 is arranged along the X direction. The −X direction end of the spring 84 is connected to the long arm 87. The spring 84 biases the long arm 87 in the +X direction. The spring 84 holds the engagement protrusion 88 of the first arm 80 in a state of being engaged with the engagement recess 93 of the second arm 90.

When the second protrusion 78 of the relay arm 70 moves in the −Y direction, the second protrusion 78 pushes the first arm hole 83 in the −Y direction. The first arm 80 rotates counterclockwise around the arm pin 81 in the −Z direction. The first arm 80 rotates against the biasing force of the spring 84. The engagement protrusion 88 moves in the −X direction and is disengaged from the engagement recess 93 of the second arm 90. As a result, the engagement between the engagement protrusion 88 and the engagement recess 93 is released.

The second arm 90 is arranged in the +X direction of the first arm 80, as shown in FIG. The second arm 90 is formed in a long plate shape extending in the X direction, and is arranged parallel to the XY plane. An arm pin 91 is arranged at the center of the second arm 90 in the X direction. The second arm 90 is rotatable around an arm pin 91 extending in the Z direction.

An engaging recess 93 is formed at the −X direction end of the second arm 90. The engagement concave portion 93 is formed so as to cover the engagement convex portion 88 following the outer shape of the engagement convex portion 88 of the first arm 80. The −X direction tip of the second arm 90 is arranged in the −X direction and the −Y direction with respect to the +Y direction tip of the engagement protrusion 88. As a result, the engagement protrusion 88 and the engagement recess 93 are held in the engaged state.
A notch 98 is formed at the +X direction end of the second arm 90. The notch 98 is formed in a rectangular shape at the center of the second arm 90 in the Y direction. The notch 98 engages with the stopper pin 103 of the stopper 100.

The stopper 100 is arranged in the +X direction, the +Y direction, and the +Z direction of the second arm 90, as shown in FIG. The stopper 100 is arranged at the same position in the X direction as the driving shaft 10. The stopper 100 is formed in a rectangular parallelepiped shape extending in the Y direction. As shown in FIG. 2, a stopper guide 106 extending in the Y direction is arranged in the +X direction and the −X direction of the stopper 100. The stopper 100 is movable in the Y direction along the stopper guide 106. A return lever 109 is erected on the surface of the stopper 100 in the +Z direction. As will be described later, the return lever 109 is used for returning the electric operating device 1 to a state in which it can be normally operated.

As shown in FIG. 3, a stopper pin 103 is installed at the end of the stopper 100 in the −Y direction. The stopper pin 103 projects in the −Z direction of the stopper 100. The stopper pin 103 engages with the notch 98 of the second arm 90. A spring 104, which is an elastic member, is arranged in the −Z direction of the stopper 100. The spring 104 extends along the Y direction. The −Y direction end of the spring 104 is connected to the stopper pin 103. The spring 104 biases the stopper pin 103 and the stopper 100 in the +Y direction.

An engagement recess 108 is formed near the end of the stopper 100 in the +Y direction. The engagement recess 108 is recessed from both ends of the stopper 100 in the X direction toward the center. In the +Y direction of the engagement recess 108, a protrusion protruding in the +X direction and the −X direction of the stopper 100 is formed.

The stopper receiver 110 is attached to the drive shaft 10. The stopper receiver 110 is arranged at the same position in the Z direction as the stopper 100. The stopper receiver 110 is formed in a disk shape and has notches 112 at two locations on the outer circumference. The width of the notch 112 in the circumferential direction of the stopper receiver 110 is larger than the width of the stopper 100 in the X direction. Engagement protrusions 113 are formed on the outer ends of the notches 112 in the radial direction of the stopper receiver 110 so as to reduce the opening width of the notches 112 in the circumferential direction. A recess is formed inside the engagement protrusion 113 in the radial direction of the stopper receiver 110 so as to enlarge the notch 112 in the circumferential direction.

In the state where the engaging protrusion 88 of the first arm 80 and the engaging recess 93 of the second arm 90 are engaged, the notch 98 of the second arm 90 holds the stopper pin 103 in the −Y direction. The second arm 90 holds the stopper pin 103 in the −Y direction against the biasing force of the spring 104. As a result, the stopper 100 is held at the position retracted from the stopper receiver 110 in the −Y direction. The stopper 100 is arranged at a retracted position that allows the rotation of the driving shaft 10.

The engagement state is released when the engagement protrusion 88 moves in the -X direction and separates from the engagement recess 93. As a result, the second arm 90 becomes rotatable. The notch 98 of the second arm 90 is engaged with the stopper pin 103. The stopper pin 103 is biased in the +Y direction by the spring 104. The second arm 90 is rotated counterclockwise in the −Z direction about the arm pin 91 by the urging force of the spring 104. The stopper pin 103 and the stopper 100 move in the +Y direction by the biasing force of the spring 104. The stopper receiver 110 rotates together with the driving shaft 10. The stopper 100 enters the notch 112 of the stopper receiver 110. The engagement recess 108 of the stopper 100 engages with the engagement protrusion 113 of the stopper receiver 110. The stopper 100 is arranged at a stop position where the rotation of the drive shaft 10 is stopped. As a result, the rotation of the stopper receiver 110 and the drive shaft 10 is stopped.

The operation of the limit tap limiting device 15 will be described. Here, an operation will be described as an example in which the limit tap limiting device 15 stops the load tap changer LTC at the high-side limit tap position.

In the electric operating device 1 shown in FIG. 1, the control board unit 3 rotates the motor 5. The control board unit 3 rotates the motor 5 in a direction in which the tap position of the tap changer LTC under load shifts to the higher position side. The torque of the motor 5 is transmitted to the outer peripheral side (input side) of the torque limiter 12 via the motor pulley 6, the first timing belt 8 and the drive shaft first pulley 13 shown in FIG. The main drive shaft 10 is connected to the inner peripheral side (output side) of the torque limiter 12, and the load tap changer LTC is connected to the main drive shaft 10. The load torque of the load tap changer LTC is smaller than the limit torque (predetermined torque) of the torque limiter. Therefore, torque is transmitted through the torque limiter 12, and the drive shaft 10 rotates.

The rotation of the drive shaft 10 shifts the tap position of the load tap changer LTC shown in FIG. 1 to the higher position. For example, when the drive shaft 10 rotates 33 times, the tap position of the tap changer LTC under load is shifted by one step. The control board unit 3 grasps the tap position of the load tap changer LTC based on the rotational position of the drive shaft 10 detected by the rotation detector 18. The control board unit 3 stops the motor 5 every time the tap position of the load tap changer LTC shifts by one step. When the tap changer LTC under load reaches the high-side limit tap position, the control board unit 3 outputs an electric signal to stop the motor 5. That is, the electric operating device 1 electrically stops the rotation of the driving shaft 10.
The limit tap limiting device 15 mechanically stops the rotation of the driving shaft 10 when the rotation stop of the electric driving shaft 10 does not function electrically.

As shown in FIG. 3, the rotation of the driving shaft 10 causes the worm shaft 28 to rotate via the driving shaft second pulley 23, the second timing belt 24, and the worm pulley 25. The rotation of the worm shaft 28 causes the feed screw shaft 32 to rotate via the worm wheel 34. For example, when the driving shaft 10 rotates 33 times, the feed screw shaft 32 rotates once. The rotation of the feed screw shaft 32 causes the feed screw nut 42 to move in the X direction. When the driving shaft 10 rotates in the direction of shifting the tap position to the higher position, the feed screw nut 42 moves in the +X direction.

FIG. 8 is a first operation explanatory diagram of the extreme tap limiting device of the embodiment. The high-side piece 48 a connected to the feed screw nut 42 moves in the +X direction together with the feed screw nut 42. When the load tap changer LTC reaches the high-side limit tap position, the high-side piece 48a comes into contact with the piece receiving portion 68a of the high-side arm 60a. Even when the load tap changer LTC reaches the high-side limit tap position, when the electric rotation stop of the electric drive shaft 10 does not function, the drive shaft 10 continues to rotate. The high-order side piece 48a further moves in the +X direction and pushes the piece receiving portion 68a in the +X direction. The higher arm 60a rotates clockwise around the arm pin 61a in the -Z direction. The higher arm 60a pushes the slider pin 58 in the +Y direction. As a result, the slider 56 moves in the +Y direction.

When the slider 56 moves in the +Y direction, the relay arm 70 rotates counterclockwise around the arm pin 71 in the −X direction. Interlocking with the relay arm 70, the first arm 80 rotates counterclockwise around the arm pin 81 in the −Z direction. The engagement protrusion 88 of the first arm 80 is held in a state of being engaged with the engagement recess 93 of the second arm 90 by the biasing force of the spring 84. The first arm 80 rotates against the biasing force of the spring 84.

FIG. 9 is a second operation explanatory diagram of the extreme tap limiting device according to the embodiment. The engagement protrusion 88 of the first arm 80 engages with the engagement recess 93 of the second arm 90. The notch 98 of the second arm 90 engages with the stopper pin 103 of the stopper 100. The stopper 100 is held at the retracted position retracted from the stopper receiver 110 in the −Y direction.
When the first arm 80 rotates, the engagement protrusion 88 moves in the −X direction. FIG. 9 shows a state immediately before the engaging projection 88 is disengaged from the engaging recess 93.

FIG. 10 is a third operation explanatory diagram of the extreme tap limiting device of the embodiment. When the first arm 80 further rotates, the engagement protrusion 88 of the first arm 80 separates from the engagement recess 93 of the second arm 90. As a result, the engagement between the engagement protrusion 88 and the engagement recess 93 is released, and the second arm 90 becomes rotatable. The notch 98 of the second arm 90 is engaged with the stopper pin 103. The stopper pin 103 is biased in the +Y direction by the spring 104. The second arm 90 is rotated counterclockwise in the −Z direction about the arm pin 91 by the urging force of the spring 104. The stopper pin 103 and the stopper 100 move in the +Y direction by the biasing force of the spring 104. The stopper receiver 110 rotates together with the driving shaft 10. The stopper 100 enters the notch 112 of the stopper receiver 110. The engaging recess 108 of the stopper 100 engages with the engaging protrusion 113 of the stopper receiver 110. The stopper 100 is arranged at a stop position where the rotation of the drive shaft 10 is stopped. As described above, the limit tap limiting device 15 mechanically stops the rotation of the driving shaft 10.

The rotation of the drive shaft 10 is stopped after the load tap changer LTC reaches the high-side limit tap position and before it reaches the high-side limit tap position one step higher. For example, the rotation of the driving shaft 10 is stopped when the driving shaft 10 rotates about 5 times after reaching the high-side limit tap position. This prevents the load tap changer LTC from being switched to a tap position beyond the high-side limit tap position.

The motor 5 of the electric operating device 1 continues to rotate even if the limit tap limiting device 15 stops the rotation of the driving shaft 10. Even in this case, the torque limiter 12 shown in FIG. 2 limits the torque transmission from the motor 5 to the drive shaft 10 to a predetermined torque. As a result, it is possible to suppress an excessive torque from acting on the limit tap limiting device 15 that stops the rotation of the driving shaft 10.

The work of returning the electric operating device 1 to the normal operation state after the extreme tap limiting device 15 mechanically stops the rotation of the driving shaft 10 will be described.
The operator operates the return lever 109 shown in FIG. 2 to move the stopper 100 in the −Y direction. As shown in FIG. 9, the second arm 90 rotates clockwise around the arm pin 91 in the −Z direction. The operator rotates the driving shaft 10 by the motor 5 or manually in the direction in which the tap position of the load tap changer LTC shifts to the lower position side. As a result, the high position side piece 48a moves in the -X direction and separates from the piece receiving portion 68a of the high position side arm 60a. The high-order side arm 60a, the slider 56, the relay arm 70, and the first arm 80 are in a rotatable or movable state. The first arm 80 is rotated clockwise about the arm pin 81 in the −Z direction by the urging force of the spring 84. As a result, the engagement protrusion 88 of the first arm 80 engages with the engagement recess 93 of the second arm. The stopper 100 is held at the retracted position retracted from the stopper receiver 110 in the −Y direction. As described above, the electric operating device 1 returns to a state in which it can operate normally.

As described in detail above, the extreme tap limiting device 15 of the embodiment has the feed screw mechanism 40a, the tops 48a and 48b, and the rotation stop unit 15a. The feed screw mechanism 40 a includes a feed screw shaft 32 that rotates in conjunction with the driving shaft 10. The driving shaft 10 is arranged in the torque transmission path from the motor 5 to the load tap changer LTC. The tops 48a and 48b move in the axial direction of the feed screw shaft 32 by the feed screw mechanism 40a. The rotation stop unit 15a can stop the rotation of the driving shaft 10 by contacting the tops 48a and 48b at the axial position corresponding to the limit tap position of the load tap changer LTC.

The feed screw mechanism 40a moves the tops 48a and 48b to stop the rotation of the driving shaft 10, so that the limit tap limiting device 15 is downsized. Since the timing for stopping the rotation of the drive shaft 10 is adjusted only by adjusting the positions of the tops 48a and 48b in the X direction, the adjustment work of the limit tap limiting device 15 is facilitated.

The limit tap limiting device 15 has a torque limiter 12 that limits torque transmission from the motor 5 to the drive shaft 10.
At the extreme tap position, the extreme tap limiting device 15 stops the rotation of the driving shaft 10. At this time, the torque limiter 12 limits the transmission torque from the motor 5 to the drive shaft 10 to a predetermined torque. As a result, it is possible to suppress an excessive torque from acting on the limit tap limiting device 15. The torque limiter 12 limits the transmission torque only when the motor 5 does not stop even when the limit tap position is reached.

This makes it unnecessary to interrupt the torque transmission from the motor 5 to the drive shaft 10 when the motor 5 does not stop even when it reaches the extreme tap position. Along with this, a sliding mechanism for interrupting the torque transmission becomes unnecessary. Even when the rotation direction of the motor 5 is reversed and the advancing direction of tap switching is reversed, the drive shaft 10 rotates without a sliding mechanism. Therefore, it is not necessary to consider wear of the sliding mechanism due to friction. Further, it is not necessary to consider the friction balance of the sliding mechanism. That is, no special consideration is given to the accuracy of the parts of the sliding mechanism. Further, the limit tap limiting device 15 can be easily assembled. Therefore, the reliability of the limit tap limiting device 15 is improved, and the manufacturing cost is suppressed.

The

pieces

48a and 48b have a high-side piece 48a and a low-side piece 48b. The rotation stop unit 15a includes a high-side arm 60a, a low-side arm 60b, a slider 56, and a rotation stop mechanism 15b. The high-side arm 60a is rotatable by contacting with the high-side piece 48a at a position in the X direction corresponding to the high-side extreme tap position of the load tap changer LTC. The lower arm 60b contacts the lower piece 48b at a position in the X direction corresponding to the lower limit tap position of the load tap changer LTC, and is rotatable. The slider 56 engages with the higher arm 60a and the lower arm 60b. The slider 56 is slidable with the rotation of the high-side arm 60a and the low-side arm 60b. The rotation stop mechanism 15b can stop the rotation of the driving shaft 10 by sliding the slider 56.
As a result, the operations of the slider 56 and the rotation stop mechanism 15b become the same at the high-side extreme tap position and the low-side extreme tap position. Therefore, the adjustment work of the extreme tap limiting device 15 becomes easy.

The higher arm 60a has a short arm 67a and a long arm 62a. The short arm 67a extends from the arm pin 61a, which is the center of rotation on the high side, to the piece receiving portion 68a, which is the contact position with the piece 48a on the high side. The long arm 62a extends from the arm pin 61a to the arm hole 63a where the slider 56 is engaged. The long arm 62a is longer than the short arm 67a.
The lower arm 60b has a short arm 67b and a long arm 62b. The short arm 67b extends from the arm pin 61b, which is the lower rotation center, to the piece receiving portion 68b, which is the contact position with the lower piece 48b. The long arm 62b extends from the arm pin 61b to the arm hole 63b where the slider 56 is engaged. The long arm 62b is longer than the short arm 67b.
As a result, the movement amount of the slider 56 increases even if the movement amount of the high-order piece 48a is small or the movement amount of the low-side piece 48b is small. Therefore, the accuracy of the operation of the rotation stop mechanism 15b is improved.

The rotation stop mechanism 15b has a stopper 100 and a stopper holding mechanism 15c. The stopper 100 is movable between a stop position that stops the rotation of the driving shaft 10 and a retracted position that allows the rotation of the driving shaft 10. The stopper 100 is biased toward the stop position. The stopper holding mechanism 15c can hold the stopper 100 at the retracted position and release the holding of the stopper 100 by sliding the slider 56.
The stopper 100 is urged toward a stop position where the rotation of the drive shaft 10 is stopped. When the holding of the stopper 100 by the stopper holding mechanism 15c is released, the stopper 100 instantly moves to the stop position to stop the rotation of the driving shaft 10. This improves the accuracy of the operation of the extreme tap limiting device 15.

The stopper holding mechanism 15c has a first arm 80 and a second arm 90. The second arm 90 engages with the stopper 100. The first arm 80 holds the stopper 100 in the retracted position while being engaged with the second arm 90. The first arm 80 is biased in a direction in which the engagement with the second arm 90 is maintained. The first arm 80 can be disengaged from the second arm 90 by sliding the slider 56.
Accordingly, the stopper holding mechanism 15c can hold the stopper 100 in the retracted position in a stable state. The stopper holding mechanism 15c can release the holding of the stopper 100 at the retracted position by sliding the slider 56.

The electric operating device 1 of the load tap changer LTC of the embodiment includes a motor 5, a main shaft 10, and the above-described limit tap limiting device 15. The driving shaft 10 is arranged in the torque transmission path from the motor 5 to the load tap changer LTC.
The limit tap limiting device 15 is arranged near the driving shaft 10 as a small unit. As a result, the electric operating device 1 for the load tap changer LTC is downsized.

The electric operating device 1 includes a multi-rotation absolute position detection type rotation detector 18 that detects the rotation position of the drive shaft 10.
The multi-rotation absolute position detection type rotation detector 18 accurately detects the rotation position of the driving shaft 10. Therefore, the stopping accuracy of the driving shaft 10 is improved. This improves the accuracy of the operation of the limit tap limiting device 15 at the limit tap position.

According to at least one embodiment described above, the feed screw mechanism 40a and the tops 48a and 48b are provided. Thereby, the limit tap limiting device can be downsized.

Although some 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, replacements, and changes can be made without departing from the spirit of the invention. These embodiments and modifications thereof are included in the invention described in the claims and equivalents thereof as well as included in the scope and the gist of the invention.

LTC... Tap changer under load, 1... Electric operation device, 5... Motor, 8... First timing belt, 10... Main shaft, 12... Torque limiter, 15... Extreme tap limiting device, 15a... Rotation stop unit, 15b... Rotation stop mechanism, 15c...Stopper holding mechanism, 18...Rotation detector, 32...Feed screw shaft, 40a...Feed screw mechanism, 48a...Higher side piece, 48b...Lower side piece, 56...Slider, 60a...Higher side arm, 60b...Lower side arm, 62a...Long arm (higher side long arm), 62b...Long arm (lower side long arm), 67a...Short arm (higher side short arm), 67b...Short arm (lower side short arm), 80... 1st arm, 90... 2nd arm, 100... Stopper.

Claims

A feed screw mechanism including a feed screw shaft that rotates in conjunction with a main shaft that is arranged in a torque transmission path from a motor to a load tap changer,
A top that moves in the axial direction of the feed screw shaft by the feed screw mechanism,
A rotation stop unit capable of stopping the rotation of the driving shaft by contacting the top at a position in the axial direction corresponding to the limit tap position of the load tap changer.
Extreme tap limiting device.
A torque limiter for limiting torque transmission from the motor to the drive shaft,
The limit tap limiting device according to claim 1.
The top has a high-side top and a low-side top,
The rotation stop unit,
A high-side arm that is rotatable and abuts the high-side piece at a position in the axial direction corresponding to the high-side extreme tap position of the load tap changer;
A low-side arm that contacts the low-side piece at a position in the axial direction that corresponds to the low-side extreme tap position of the load tap changer and that is rotatable,
A slider that is engaged with the high-order side arm and the high-order side arm and is slidable with the rotation of the high-order side arm and the high-order side arm;
A rotation stop mechanism capable of stopping the rotation of the drive shaft by sliding the slider,
Has,
The limit tap limiting device according to claim 1 or 2.
The high-side arm includes a high-side short arm extending from the high-side rotation center to a contact position with the high-side piece, and a high-side long arm extending from the high-side rotation center to an engagement position with the slider. Has,
The high-side long arm is longer than the high-side short arm,
The low-side arm includes a low-side short arm extending from the low-side rotation center to a contact position with the low-side top, and a low-side long arm extending from the low-side rotation center to an engagement position with the slider. Has,
The low-side long arm is longer than the low-side short arm,
The limit tap limiting device according to claim 3.
The rotation stop mechanism is
A stopper that is movable between a stop position that stops rotation of the drive shaft and a retracted position that allows rotation of the drive shaft, and is biased toward the stop position;
A stopper holding mechanism capable of holding the stopper at the retracted position and releasing the holding of the stopper by sliding the slider;
Has,
The extreme tap limiting device according to claim 3 or 4.
The stopper holding mechanism has a first arm and a second arm,
The second arm engages with the stopper,
The first arm holds the stopper in the retracted position while being engaged with the second arm, and is urged in a direction of retaining the engagement with the second arm, and the first arm is slid to move the first arm. It is possible to release the engagement with the two arms,
The extreme tap limiting device according to claim 5.
An extreme tap limiting device according to any one of claims 1 to 6,
The motor,
The drive shaft arranged in a torque transmission path from the motor to the load tap changer,
Electric operation device for tap changer under load.
It has a multi-rotation absolute position detection type rotation detector for detecting the rotation position of the drive shaft,
An electrically operated device for a load tap changer according to claim 7.