JP2024068848A - Short-circuit grounding instrument and grounding construction method using the same - Google Patents

Abstract

To provide a short-circuit grounding instrument which can be easily attached and detached to/from an operation wire with a single operation rod, and does not fall out in an operation.SOLUTION: A short-circuit grounding instrument 1 includes: a gripping part 2 that grips an operation wiring W; an operation part 3 that operates the gripping part 2 with an insulation operation rod 16; and a grounding wiring 4 that is connected to the gripping part 2. The gripping part 2 grips and releases the operation wiring W by a hook body 5 and a gripping member 6. A trigger member 7 contacts to the gripping member 6 and holds them at a release position before a mounting of the gripping member to the operation wiring W, and releases the gripping member 6 to a gripping position by being depressed to the operation wiring W at the time of the mounting. A knock rod 8 is set to a non-lock position so as to be twisted and locked to an insertion pipe 9 before the mounting, releases the set by the insulation operation rod 16 connected to the operation part 3 at the time of mounting, and locks the gripping member 6 so as to be projected to the lock position with a spring force.SELECTED DRAWING: Figure 8

Description

The present invention relates to a grounding device used for grounding a work line when performing work on an overhead power transmission line, and a grounding method using the same.

When carrying out overhead power line work, measures are taken to ground the work line to a grounding body such as a tower in order to prevent workers from getting an electric shock. In line work, in order to ensure safety, it is important that the work is carried out only after confirming that the work line has been securely grounded, and that the grounding is not released during work.
Conventionally, a short circuit earthing device is known, for example, as described in Patent Document 1. This device is capable of clamping a working line with a fixed arm and a rotatable movable arm, and the rotation of the movable arm is restricted by a locking part. The locking part includes a ratchet gear and a locking pawl that is biased toward the ratchet gear, and the locking pawl is provided with an unlocking part for releasing the engagement between the ratchet gear and the locking pawl. Meanwhile, the fixed arm is provided with an insertion part into which an operating rod for supporting the device can be inserted.

JP 2009-177898 A

In the above-mentioned conventional short-circuit earthing device, when attaching or detaching it to or from the working line, it is necessary to support the device with an operating rod while operating the locking part with another operating rod (binding tool), and there is a problem in that the operations of attaching and detaching it to or from the working line are complicated.
Therefore, the present invention aims to provide a short-circuit earthing device that can be easily attached to and detached from a work line by simply operating a single operating rod, and that can be securely attached to the work line so that it will not fall off during work, and to provide a grounding method using the same.

In the following description, reference will be made to the numerals in the accompanying drawings, but the invention is not limited thereto.
In order to solve the above problems, the short-circuit earthing device 1 of the present invention comprises a gripping section 2 for gripping a working line W of an overhead power transmission line, an operating section 3 for operating the gripping section 2 with an insulated operating rod 16, and a grounding conductor 4 having one end connected to the gripping section 2 and the other end connected to a grounding section. The gripping section 2 comprises a hook body 5 having a generally C-shaped shape with a side-opening portion 51 for hanging on the working line W, a gripping member 6 pivotally supported on the hook body 5 so as to grip and release the working line W hung on the hook body 5 between the hook body 5, a trigger member 7 supported on the hook body 5 so as to control the gripping and release operation of the gripping member 6, a knock rod 8 supported on the hook body 5 so as to restrain and release the gripping member 6 at the gripping position, and an insertion tube 9 supported on the hook body 5 so as to insert the knock rod 8. The gripping member 6 is rotatable between a gripping position and a release position, and is rotatably biased to the gripping position. The trigger member 7 is movable between a holding position where the gripping member 6 is energized and held in the release position and a release position where the gripping member 6 is released to perform a gripping operation, and is pushed by the working line W by pulling the hook body 5 to move to the release position. The knock rod 8 is axially movable between a locked position where the gripping member 6 is abutted against the gripping member 6 and held in the gripping position and an unlocked position where the gripping member 6 is released from the gripping member 6, and is biased to the locked position and is rotatable about its axis between the unlocked position and the energized position. The insertion tube 9 inserts the knock rod 8 axially movable and rotatable about its axis between the unlocked position and the energized position, energizes and holds the knock rod 8 in the unlocked position at the energized position, and releases the knock rod 8 to project to the locked position at the unlocked position. The operation unit 3 includes a connection member supported by the knock rod 8 so as to receive an insulating operation rod 16 that rotates the knock rod 8 about its axis.
The grounding method using the short-circuit grounding device 1 of the present invention includes a first step of connecting the grounding conductor 4 to the grounding portion; a second step of rotating the gripping member 6 to the release position with respect to the hook body 5 to store energy, moving the trigger member 7 to the holding position to hold the gripping member 6 in the release position, and rotating the knock rod 8 to the stored position to engage with the insertion tube 9 while moving the knock rod 8 in the axial direction to an unlocked position away from the gripping member 6; a third step of inserting the tip side of the insulating operating rod 16 into the operating portion 3 to connect it to the knock rod 8 in the unlocked position; a fourth step of hanging the hook body 5 on a working line W located at a distance via the insulating operating rod 16 and arranging the working line W below the trigger member 7; and a fourth step of pulling down the hook body 5 via the insulating operating rod 16, and pushing up the trigger member 7, which is in the held position, to the release position by the working line W located below the trigger member 7, thereby a fifth step of rotating the knock rod 8 to a gripping position and gripping the working line W between the hook body 5 and the hook body 5; a sixth step of rotating the knock rod 8, which is in the unlocked position, about the axis via the insulating operating rod 16 to a release position, thereby pressing it against the underside of the gripping member 6; a seventh step of disconnecting the insulating operating rod 16 from the knock rod 8 and removing it from the operating unit 3, leaving the operating unit 3 and the gripping unit 2 on the working line W; an eighth step of connecting the tip side of the insulating operating rod 16 to the operating unit 3 on the working line W after work on the working line W is completed, and pulling the knock rod 8 down to an unlocked position away from the gripping member 6 while rotating it about the axis to the energized position to engage with the insertion tube 9; and a ninth step of pushing up the hook body 5 via the insulating operating rod, rotating the gripping member 6 to the release position by the pressing force of the working line W, and removing the hook body 5 from the working line W.

The present invention provides a short-circuit grounding device that can be easily attached to and detached from a work line by simply operating a single control rod, and can be securely attached to a work line so that it does not fall off during work, as well as a grounding method that uses this device to easily and reliably achieve short-circuit grounding.

1 is a perspective view of a short-circuit grounding device according to a first embodiment of the present invention; FIG. 2 is a front view of the short circuit grounding device of FIG. 1; FIG. 2 is a side view of the short circuit grounding tool of FIG. 1, showing the tool in a state prior to gripping the working line; FIG. 2 is a side view of the short circuit grounding tool of FIG. 1 , showing the working line being gripped; FIG. 2 is a plan view of the short circuit grounding device of FIG. 1; FIG. 2 is a front view of the short-circuit grounding device of FIG. 1 with a portion cut away. FIG. 2 is a side view of the short-circuit grounding device of FIG. 1 with a portion cut away. FIG. 2 is a partially cutaway plan view of the short-circuit grounding device of FIG. 1; FIG. 2 is an exploded perspective view of a portion of the short circuit grounding device of FIG. 1; 2 is a longitudinal sectional view showing the relationship between the operating portion, the insulating operating rod, and the knock rod in the short-circuit grounding device of FIG. 1, showing a state before the insulating operating rod is inserted. FIG. 2 is a longitudinal cross-sectional view showing the relationship between the operating portion, the insulating operating rod, and the knock rod in the short-circuit grounding device of FIG. 1, and shows a state in which the insulating operating rod is inserted and the engagement protrusion is disposed in the horizontal groove portion of the twist lock groove. 2 is a longitudinal cross-sectional view showing the relationship between the operating portion, the insulating operating rod, and the knock rod in the short-circuit grounding device of FIG. 1, and shows a state in which the insulating operating rod is inserted and the engagement protrusion is disposed in the holding groove portion of the twist lock groove. 10-1(A) is a schematic cross-sectional view of the a-a portion in FIG. 9-3, 10-1(B) is a schematic cross-sectional view of the b-b portion in FIG. 9-3, and 10-1(C) is a schematic cross-sectional view of the c-c portion in FIG. 9-3. 10-2(A) is a schematic cross-sectional view of the a-a portion in FIG. 9-3 in a state in which the knock rod is rotated in the arrow direction together with the connecting tube by the insulated operating rod, 10-2(B) is a schematic cross-sectional view of the b-b portion in FIG. 9-3, and 10-2(C) is a schematic cross-sectional view of the c-c portion in FIG. 9-3. 6 is a side view showing a part of a short-circuit grounding device according to a second embodiment of the present invention, with a cutaway portion. FIG. FIG. 11 is a side view showing a part of a short-circuit grounding device according to a third embodiment of the present invention, with a cutaway portion.

A first embodiment of the present invention will be described with reference to FIGS.
In the drawings, the short-circuit earthing device 1 comprises a gripping part 2 for gripping a working line W of an overhead power transmission line, an operating part 3 for operating the gripping part 2 with an insulated operating rod 16, and a grounding conductor 4 having one end connected to the gripping part 2 and the other end connected to a grounding part. For convenience, the following description will be given with the gripping part 2 side as the upper side and the operating part 3 side as the lower side, but the short-circuit earthing device 1 is not always used in this orientation.

The gripping section 2 includes a hook body 5 for hanging on the working line W, a gripping member 6 for gripping the working line W to which the hook body 5 is hung between the hook body 5 and the gripping member 6, a trigger member 7 for holding and releasing the gripping member 6, a knock rod 8 for contacting and separating from the gripping member 6, and an insertion tube 9 for inserting the knock rod 8.

The hook body 5 is a roughly C-shaped metal member with an opening 51 that opens to the side, and is equipped with an upper jaw 52 that is hung on the working line W, and a lower jaw 53 that faces the upper jaw 52 via the opening 51. The upper jaw 52 is composed of a pair of parallel plate sections 52a. The lower surface of the upper jaw 52 is provided with a roughly inverted V-shaped recess 52b for guiding the working line W to the center of the upper jaw 52. The upper surface of the lower jaw 53 has an outwardly sloping surface 53b.

The gripping member 2 is pivoted by a pivot pin 61 between the plate portions 52a on the tip side of the upper jaw portion 52 at the base end, and is freely rotatable between a gripping position (Fig. 3(B)) in which the gripping member 2 grips the working line W between the upper jaw portion 52 and the release position (Fig. 3(A)) in which the working line W is released, and is rotatably biased to the gripping position by a spring 62.

The trigger member 7 is a roughly rectangular metal block having a pair of long parallel holes 7a in the vertical direction, and is supported by a support pin 71 between the plate portions 52a of the upper jaw portion 52 so that it can move up and down freely, adjacent to the base end side of the gripping member 2.

At the lower holding position (Fig. 3-1), the trigger member 7 holds the gripping member 6 in the released position against the spring force, and at the upper release position (Fig. 3-2), it releases the gripping member 6 and allows it to rotate to the gripping position. As shown clearly in Fig. 6, abutment planes 6a, 7b are formed on the base end of the gripping member 2 and the adjacent side of the trigger member 7, and are configured so that when the gripping member 6 is in the released position and the trigger member 7 is in the lower holding position, the two abutment planes 6a, 7b abut against and restrain each other.

When the gripping member 6 is rotated against the spring force to the release position, the trigger member 7 moves by its own weight to a lower holding position, and when the hook body 5 hung on the working line W is pulled down, it is pushed up against the working line W and moves to an upper release position.

A generally V-shaped recess 7c that opens downward is formed in the center of the underside of the trigger member 7. The trigger member 7 is positioned so that the center of its underside roughly coincides with the center of the recess 52b of the upper jaw portion 52.

As shown clearly in Figure 6, the upper end of the knock rod 8 faces the trigger member 7, extends freely vertically through the through hole 53a of the lower jaw 53, has a stopper pin 81 on the outer periphery of the middle part, and has its lower end fixed to the outer cylinder 10. The knock rod 8 is free to move up and down between an upper locked position (Figure 3-2) and a lower unlocked position. When in the locked position, the upper end of the knock rod 8 abuts against the gripping member 6 to restrain the gripping member 6 in the gripping position, and when in the unlocked position, it moves away from the gripping member 6.

The insertion tube 9 consists of an outer tube 91 and an inner tube 92 fitted and fixed inside the outer tube 91. As shown in FIG. 8, the inner tube 92 is formed with a roughly L-shaped twist lock groove 921 consisting of a vertical groove 921a in the axial direction and a horizontal groove 921b in the circumferential direction. The stopper pin 81 of the knock rod 8 is movably engaged with this twist lock groove 921. The upper end of the insertion tube 9 is inserted and fixed into the through hole 53a of the lower jaw 53, and the knock rod 8 is inserted within the range of the twist lock groove 921 so as to be movable up and down in the axial direction and rotatable around the axis.

A compression spring 82 is fitted onto the knock rod 8, and its upper end is engaged with the upper end of the knock rod 8. The compression spring 82 is inserted into the insertion tube 9 together with the knock rod 8, and its lower end is engaged with a spring retainer 93 fixed inside the insertion tube 9. The compression spring 82 biases the knock rod 8 to the upper lock position.

The knock rod 8 compresses the compression spring 82 in the lower unlocked position where the upper end is submerged in the through hole 53a. When the knock rod 8 is rotated in the axial direction to the charged position in this unlocked position, the stopper pin 81 engages with the horizontal groove 921b of the twist lock groove 921, and the knock rod 8 is held in the unlocked position. When the knock rod 8 is rotated about 90° from there to the released position in the opposite direction, the stopper pin 81 reaches the vertical groove 921a and is released, protruding to the locked position.

As shown in FIG. 6, the operating part 3 is supported by the lower end of the knock rod 8 extending from the insertion tube 9 and receives the upper end of the insulating operating rod 16, thereby connecting the insulating operating rod 16 to the knock rod 8 so that it can be rotated around its axis.

As shown in FIG. 8, the operating unit 3 includes an outer tube 10, a connecting tube 11, and a rotation transmission mechanism 12.

The outer cylinder 10 is fixed to the lower end of the knock bar 8, and an axial engagement part consisting of a pair of engagement pins 101 protrudes from the upper inside part (Figure 5).

The connecting tube 11 is connected to the lower end of the outer tube 10 so as to be rotatable relative to the axis. The rotation transmission mechanism 12 connects the connecting tube 11 and the outer tube 10 in the direction of rotation about the axis only when the insulated operating rod 16 is received.

The connecting pipe 11 is a flared cylinder that widens downward so as to receive the tip of the insulating operating rod 16 from below, and its upper part is connected to the outer cylinder 10. The connecting pipe 11 has a twist engagement groove 111 at its lower edge that engages the engagement pin 16a of the insulating operating rod 16. The twist engagement groove 111 has a vertical groove 111a that opens at its lower end to the lower edge of the connecting pipe 11 and extends in the axial direction, a horizontal groove 111b that is continuous with the upper end of the vertical groove 111a and extends in the circumferential direction, and a retaining groove 111c that is continuous with the end of the vertical groove 111a and extends downward at a right angle.

The rotation transmission mechanism 12 includes a clutch member 13 and a spring 14 that urges the clutch member 13 downward relative to the connecting tube 11. When the clutch member 13 is pushed up to an upper engagement position by an insulating operating rod 16 received in the connecting tube 11, it connects the connecting tube 11 and the outer tube 10 in the axial rotation direction via an engagement pin 101, and disconnects the connecting tube 11 and the outer tube 10 in a lower disengagement position.

The clutch member 13 has an engagement portion 131 disposed inside the outer tube 10 and a shaft portion 132 extending perpendicularly from the center of the engagement portion 131 into the connecting tube 11.

The engaging/disengaging portion 131 is disposed below and facing the engaging pin 101 inside the outer tube 10, and is provided so as to engage with the engaging pin 101 in an upper engaging position and to disengage from the engaging pin 101 in a lower disengaging position. In the illustrated embodiment, the engaging/disengaging portion 131 is fitted into the outer tube 10 so as to be rotatable about the axis, and has a pair of engaging pieces 131a that face each other radially inside the outer tube 10. When the clutch member 13 is in the upper engaging position, the engaging pieces 131a engage with the engaging pin 101 approximately every 90° of rotation, thereby connecting the outer tube 10 and the connecting tube 11 in the axial rotation direction.

The shaft portion 132 is provided so that it can move up and down relative to the connecting pipe 11, but cannot rotate around the shaft. Therefore, the clutch member 13 rotates together with the connecting pipe 11, and when it is in the upper engagement position (Figure 9-3), the rotation is transmitted to the knock rod 8 via the engagement/disengagement portion 131, the engagement pin 101, and the outer cylinder 10.

Therefore, by inserting the insulating operating rod 16 into the connecting tube 11 and pushing up the clutch member 13 to the engaged position (Fig. 9-3), the insulating operating rod 16 can be rotated to rotate the knock rod 8 to the unenergized position (Fig. 10-2) relative to the insertion tube 9 via the connecting tube 11 and the outer tube 10, thereby causing the knock rod 8 to be protruded to the locked position (Fig. 3-2) by the push spring 82. When the insulating operating rod 16 is not inserted into the connecting tube 11 (Fig. 9-1), the clutch member 13 is in the disengaged position, so the connecting tube 11 and the outer tube 10 are free to move around the axis relative to each other, and the rotation of the connecting tube 11 is not transmitted to the knock rod 8.

When performing grounding work on the working circuit W using the short-circuit grounding device 1 configured as described above, the grounding conductor 4 is connected to a grounding part of, for example, a steel tower. A worker on the steel tower connects the tip of the insulated control rod 16 to the short-circuit grounding device 1 with the gripping part 2 set to the initial state, supports the insulated control rod 16, and hangs the short-circuit grounding device 1 on a working circuit W such as a jumper wire located away from the steel tower, and performs the required remote operation via the insulated control rod 16.

The gripping portion 2 of the short-circuit grounding device 1 can be set to its initial state, for example, as follows. The gripping member 6 is rotated to the release position against the spring 62 relative to the hook body 5, the trigger member 7 is lowered to the holding position, and the abutment planes 6a and 7b are brought into contact with each other, thereby holding the gripping member 6 in the release position. In addition, the knock rod 8 is pulled down to the lower unlocked position against the compression spring 82, and then rotated about its axis to place it in the charged position. During this time, the stopper pin 81 of the knock rod 8 moves down along the vertical groove 921a of the twist lock groove 921 of the insertion tube 9, and moves along the horizontal groove 921b to its end. This completes the setting of the gripping portion 2 to its initial state.

Then, the insulating operating rod 16 is inserted axially into the connecting pipe 11, aligning the engagement pin 16a with the twist engagement groove 111 of the connecting pipe 11. By inserting the insulating operating rod 16, the clutch member 13 is pushed up above the engagement position against the biasing spring 14. Next, the insulating operating rod 16 is rotated around its axis to position the engagement pin 16a on the lateral groove 111b (Fig. 9-2) or in the retaining groove 111c (Fig. 9-3). Up to this point, the insulating operating rod 16 rotates independently, the connecting pipe 11 does not rotate (Figs. 9-1 to 9-3), and the clutch member 13 maintains the position shown in Fig. 10-1.

The short-circuit grounding device 1, which has been set to its initial state in this way, is brought close to the working line W via the insulated operating rod 16, and the working line W is taken into the hook body 5 through the opening 51 and placed under the trigger member 7 (Figure 3-1).

Next, when the insulating operating rod 16 is pulled down to pull down the short-circuit grounding device 1, the trigger member 7 is pushed up by the working line W to the release position (Fig. 3-2), and the contact between the contact planes 6a and 7b is released. At the same time, the gripping member 6 rotates to the gripping position by the spring 62, and grips the working line W between itself and the hook body 5.

Next, when the connecting tube 11 is rotated in the direction of the arrow in Figure 10-1 via the insulating operating rod 16, the knock rod 8 rotates together with the outer tube 10 to the disengaged position via the clutch member 13 (Figure 10-2), and the stopper pin 81 moves through the horizontal groove 921b of the insertion tube 9 to the vertical groove 921a. This releases the knock rod 8, which protrudes to the locked position and whose tip is pressed against the underside of the gripping member 6 (Figure 3-2). In this state, the gripping portion 2 firmly holds the working circuit W, and the short-circuit grounding device 1 will not easily come off the working circuit W due to an external force.

Next, when the insulating operating rod 16 is pushed up and rotated around its axis, the engaging pin 16a disengages from the retaining groove 111c of the connecting pipe 11 and moves to the horizontal groove 111b and the vertical groove 111a, so that the insulating operating rod 16 can be pulled out of the connecting pipe 11 and the short-circuit grounding device 1 can be left on the working line W.

After ensuring grounding in this way, the worker performs the required work on the work line W. Even if the worker's clothing or other parts come into contact with the connecting pipe 11 at the end of the short-circuit grounding device 1 during work, the connecting pipe 11 rotates freely around its axis, so the work is not hindered and the short-circuit grounding device 1 will not fall off the work line during work.

After completing the work on the working line W, the worker on the tower reconnects the insulating operating rod 16 to the connecting pipe 11 and operates it to retrieve the short-circuit grounding device 1. This work is explained below. The tip of the insulating operating rod 16 is inserted into the connecting pipe 11 on the working line W located at a distance, and is rotated around the axis to engage the engagement pin 16a into the holding groove 111c of the twist engagement groove 111.

In this state, the short-circuit earthing device 1 is pulled via the insulating operating rod 16, and the knock rod 8 is pulled down against the compression spring 82 to the lower unlocked position, and then rotated around the axis to hold it in the charged position. Next, when the short-circuit earthing device 1 is pushed up, the gripping member 6 is pushed by the working line W and rotated to the release position. During this time, the working line W descends inside the hook body 5 while pushing open the gripping member 6, sliding along the slope 53b of the lower jaw 53 and automatically escaping from the hook body 5. Next, the insulating operating rod 16 is pulled in, and the short-circuit earthing device 1 is retrieved to hand.

Next, a second embodiment of the present invention will be described with reference to FIG. 11. The short-circuit grounding device 201 of this embodiment is the same as the previous embodiment except for the structure of the operation unit 3. Therefore, in the figure, the same components as the previous embodiment are given the same reference numerals and their description will be omitted.

In this embodiment, as in the previous embodiment, the working line W is clamped between the upper jaw 52 of the hook body 5 and the gripping member 6, and the gripping member 6 is prevented from opening by the knock rod 8, so there is no risk of the gripping part 2 easily coming off the working line W due to an external force.

The outer tube 10 and rotation transmission mechanism 12 of the previous embodiment are not provided. Therefore, the connection tube 11 is directly fixed to the lower end of the knock rod 8 and is not free from the knock rod 8. Therefore, the connection tube 11 of the short circuit grounding device 201 attached to the working line W does not rotate relative to the knock rod 8.

Next, a third embodiment of the present invention will be described with reference to FIG. 12. The short-circuit grounding device 301 of this embodiment is the same as that of the first embodiment, except that the structure of the gripping portion 2 differs from that of the first embodiment. Therefore, in the figure, the same components are given the same reference numerals and the description is omitted.

In this embodiment, the gripping portion 2 does not have the gripping member 6 of the first embodiment. The gripping portion 2 is composed of a hook body 5 and a knock rod 8.

To set it to the initial state, the knock rod 8, together with the outer tube 10 and the connecting tube 11, is pulled down to the unlocked position against the compression spring 82, and rotated around its axis to engage the stopper pin 81 with the insertion tube 9, and the open portion 51 of the hook body 5 is held in the open state.

As with the first embodiment, the connection tube 11 rotates freely relative to the knock rod 8 at all times, and only when the insulating operating rod 16 is attached and the clutch member 13 is pushed up to the engaged position does the connection tube 11 and knock rod 8 become able to rotate together in the axial direction.

Therefore, after the insulating operating rod 16 is pulled out from the connecting pipe 11 and the short-circuit grounding device 301 is left on the working line W, even if the worker touches the connecting pipe 11 while working on the working line W, the connecting pipe 11 rotates freely around its axis, so the work is not hindered and the short-circuit grounding device 1 does not fall off the working line during work.

1 Short-circuit grounding device 2 Grip portion 3 Operation portion 4 Grounding conductor 5 Hook body 51 Open portion 52 Upper jaw portion 52a Plate portion 52b Recess 53 Lower jaw portion 53a Through hole 53b Slope 6 Grip member 6a Abutment plane 61 Pivot pin 62 Spring 7 Trigger member 7a Long hole 7b Abutment plane 7c Recess 71 Support pin 8 Knock rod 81 Stopper pin 82 Compressor spring 9 Insertion tube 91 Outer tube 92 Inner tube 921 Twist lock groove 921a Vertical groove 921b Horizontal groove 93 Spring receiver 10 Outer tube 101 Engagement pin (engagement portion around axis)
11 Connection tube 111 Twist engagement groove 111a Vertical groove 111b Horizontal groove 111c Holding groove 12 Rotation transmission mechanism 13 Clutch member 131 Engagement/disengagement portion 131a Engagement piece 132 Shaft portion 14 Pressing spring 16 Insulated operation rod 16a Engagement pin 201 Short circuit grounding device (second embodiment)
301 Short circuit grounding device (third embodiment)
W Working Line

Claims (8)

A short-circuit grounding device comprising a gripping part for gripping a working line of an overhead power transmission line, an operating part for operating the gripping part with an insulated operating rod, and a grounding conductor having one end connected to the gripping part and the other end connected to a grounding part,
The gripping portion includes a generally C-shaped hook body having an opening that opens to the side for hanging on the working line, a gripping member pivotally supported on the hook body so as to be rotatable between a gripping position where the hook body grips the working line to which the hook body is hung and a release position where the working line is released, and to be rotatably biased to the gripping position, a trigger member supported on the hook body so as to be movable between a holding position where the gripping member is held in the release position and a release position where the gripping member is released, and to be pushed by the working line to which the hook body is hung and to move to the release position, and a knock rod that is supported by the hook body so as to be movable in an axial direction between a locked position where one end of the knock rod abuts against the gripping member so as to restrain the gripping member in the gripping position and an unlocked position where the knock rod is separated from the gripping member and is energized to the locked position, and is rotatable about its axis between the released position and the energized position; and an insertion tube that is fixed to the hook body at one end and that inserts the knock rod so as to be movable in the axial direction and rotatable about its axis between the released position and the energized position, and that energizes and holds the knock rod in the unlocked position at the energized position and releases it to the locked position at the unlocked position.
The operating portion is supported by the knock rod so as to receive the tip end of the insulating operating rod so as to be connectable to and separable from the knock rod. The hook body includes an upper jaw portion that is hooked onto the working line, and a lower jaw portion that faces the upper jaw portion via the opening portion,
The gripping member is pivotally supported at a base end side on a tip side of the upper jaw portion, and is rotatably biased by a spring to a gripping position so as to grip the working line between the gripping member and the upper jaw portion at the tip end side,
The short-circuit grounding device as described in claim 1, characterized in that the trigger member is supported on the upper jaw portion so as to be freely movable up and down, and is arranged so that at a lower holding position, it abuts against the gripping member to hold the gripping member in a release position, and when pressed by the working line to which the hook body is hung, it moves to an upper release position away from the gripping member and allows the gripping member to rotate to the gripping position. the knock bar is provided with a stopper pin that penetrates the lower jaw portion and the insertion tube and protrudes to an outer periphery within the insertion tube, and is biased to a lock position by a compression spring that is interposed between the knock bar and the insertion tube,
3. The short-circuit grounding device according to claim 2, wherein the insertion tube is provided with a vertical groove on an inner periphery with which the stopper pin is movably engaged to allow axial movement of the knock rod between the locked position and the unlocked position, and a circumferential lateral groove that is continuous with a lower end of the vertical groove and allows rotation of the knock rod about the axis between the released position and the activated position, and is configured so that when the stopper pin is in the activated position where it engages with the end of the lateral groove, the compression spring is activated to hold the knock rod in the unlocked position, and when the stopper pin is in the released position where it engages with the vertical groove, the knock rod is released to allow it to protrude to the locked position. A generally inverted V-shaped recess is provided on the underside of the upper jaw portion to guide the working line to the center of the upper jaw portion,
3. The short circuit grounding device according to claim 2, wherein the center of the lower portion of the trigger member is disposed in the center of the recess. the hook body includes an upper jaw portion that is hooked onto the working line and a lower jaw portion that faces the upper jaw portion across the opening,
The knock bar is freely inserted through the lower jaw portion and into the insertion tube,
2. The short-circuit grounding device according to claim 1, wherein an upper surface of the lower jaw is formed into an inclined surface that slopes downward toward the outside of the open portion, and a tip of the knock bar in an unlocked position is recessed below the inclined surface, so that when the hook body moves upward, the working line to which the hook is hooked slides relative to the inclined surface and is guided to the outside of the open portion. the operating portion comprises an outer cylinder fixed to the lower end of the knock rod and having an axial engagement portion at its upper inside portion, a flared cylindrical connecting tube connected to the lower end of the outer cylinder so as to be relatively rotatable about the axis and receive the tip end of the insulating operating rod and be rotatable about the axis, and a rotation transmission mechanism which couples the connecting tube and the outer cylinder in the axial rotation direction only when the insulating operating rod is received in the connecting tube,
the connecting pipe is provided with a twist engagement groove that receives an engagement pin protruding from the outer periphery of the insulating operating rod in the axial direction and couples the insulating operating rod to the connecting pipe in the axial rotation direction at a fixed position rotated relatively around the axis,
the rotation transmission mechanism includes a clutch member which connects the connecting pipe and the outer cylinder in the rotational direction around the axis when the clutch member is pushed up to an upper engagement position by the insulating operating rod received in the connecting pipe and which disconnects the connecting pipe and the outer cylinder at a lower disengagement position, and a biasing spring which biases the clutch member to the lower disengagement position,
2. The short-circuit grounding device according to claim 1, wherein the clutch member comprises an engaging/disengaging portion disposed in the outer cylinder below and facing the axial engagement portion, the engaging portion engaging with the axial engagement portion in an upper engaging position and disengaging from the axial engagement portion in a lower disengaging position, and a shaft portion extending from the engaging/disengaging portion into the connecting pipe, the clutch member being provided on the outer cylinder and the connecting pipe so as to be movable up and down and on the connecting pipe so as to be unable to rotate about the axis relative to the connecting pipe, and wherein a rotating operation of the insulating operating rod received in the connecting pipe rotates the knock rod via the connecting pipe and the outer cylinder to a disengaged position relative to the rod insertion pipe, thereby causing the knock rod to protrude to a locked position by a spring force. A short-circuit grounding device comprising a gripping part for gripping a working line of an overhead power transmission line, an operating part for operating the gripping part with an insulated operating rod, and a grounding conductor having one end connected to the gripping part and the other end connected to a grounding part,
The gripping portion includes a generally C-shaped hook body having a sideward opening for hanging on the working line, and a knock rod supported through the hook body so as to hold and release the working line to which the hook body is hung at an upper end between the hook body and the knock rod,
the knock rod is movable in an axial direction between a locked position for holding the working line and an unlocked position for releasing the working line, is biased to a locked position, and is supported by the hook body so as to be rotatable about an axis between a released position and an activated position;
the operating portion includes an outer cylinder fixed to the lower end of the knock rod and having an axial engagement portion at an upper inside portion, a flared cylindrical connecting tube connected to the lower end of the outer cylinder so as to be relatively rotatable about the axis and capable of receiving the tip end of the insulating operating rod and being rotatable about the axis, and a rotation transmission mechanism which connects the connecting tube and the outer cylinder in the axial rotation direction only when the insulating operating rod is received in the connecting tube,
the connecting pipe is provided with a twist engagement groove that receives an engagement pin protruding from the outer periphery of the insulating operating rod in the axial direction and couples the insulating operating rod to the connecting pipe in the axial rotation direction at a fixed position rotated relatively around the axis,
the rotation transmission mechanism includes a clutch member that connects the connecting pipe and the outer cylinder in the rotational direction around the axis when the clutch member is pushed up to an upper engagement position by the insulating operating rod received in the connecting pipe and that disconnects the connecting pipe and the outer cylinder at a lower disengagement position, and a biasing spring that biases the clutch member to the lower disengagement position,
the clutch member comprises an engaging/disengaging portion disposed below and facing the axial engagement portion within the outer cylinder, the engaging portion engaging with the axial engagement portion in an upper engaging position and disengaging from the axial engagement portion in a lower disengaging position, and a shaft portion extending from the engaging/disengaging portion into the connecting pipe, the clutch member being movable up and down on the outer cylinder and the connecting pipe and being immovable relative to the connecting pipe about the axis, and being disposed so that rotation of the insulating operating rod received in the connecting pipe rotates the knock rod via the connecting pipe and the outer cylinder to a disengaged position relative to the rod insertion tube, thereby causing the knock rod to protrude to a locked position by a spring force. A grounding method using the short-circuit grounding device according to claim 1, comprising: a first step of connecting the grounding conductor to a ground part;
a second step of rotating the gripping member to a release position relative to the hook body to store the force, moving the trigger member to a holding position to hold the gripping member at the release position, and moving the knock rod in the axial direction to an unlocked position away from the gripping member while rotating the knock rod to a stored position to engage with the insertion tube;
a third step of inserting a tip end side of the insulating operating rod into the operating portion to connect it to the knock rod in the unlocked position;
a fourth step of hooking the hook body to the working line at a remote position via the insulating operating rod and arranging the working line under the trigger member;
a fifth step of pulling down the hook body via the insulating operating rod, and pushing up the trigger member, which is in a holding position on the working line located under the trigger member, to a release position, thereby rotating the gripping member to a gripping position and gripping the working line between the gripping member and the hook body;
a sixth step of rotating the knock rod, which is in the unlocked position, around the axis to a disengaged position via the insulating operating rod, thereby pressing the knock rod against a lower surface of the gripping member;
a seventh step of disconnecting the insulating operating rod from the knock rod and removing the operating part from the operating part, and leaving the operating part and the grip part on the working line;
an eighth step of connecting a tip end side of the insulating operating rod to an operating part on the working line after the work on the working line is completed, and pulling the knock rod down to an unlocked position away from the gripping member while rotating the knock rod about an axis to a loaded position to engage the knock rod with the insertion tube;
This earthing method is characterized by including a ninth step following the eighth step, in which the hook body is pushed up via the insulating operating rod, and the gripping member is rotated to a release position by the pressing force of the working line, thereby removing the hook body from the working line.

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