Wire cutting tool

Abstract

To provide an electric wire cutting tool capable of efficiently and safely cutting through operation performed from the ground, an electric wire arranged in a high place.SOLUTION: An electric wire cutting tool 1 comprises: an upper jaw part 6 formed in a substantially C-shape in a side view, and having a lower face 6a formed in a recessed shape protruding upward in the side view; a pedestal base 7 arranged in such a manner that an upper face 7a is opposed to the lower face 6a of the upper jaw part 6; a connection part 8 connecting the upper jaw part 6 with the pedestal base 7; a clamp 2a constituted of a base 9 arranged on a lower face 7b of the pedestal base 7; an electric wire cutting mechanism 3 and a voltage detector 4 attached to the clamp 2a; and a connection mechanism 5 for attaching the clamp 2a to a shared operation rod S.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a tool used for cutting electric wires installed at high places, and more particularly to an electric wire cutting tool that allows the cutting work to be performed safely from the ground. [Background technology]

[0002] When a house is demolished, it is necessary to remove the service lines, but traditionally, ladders and aerial work vehicles have been used to remove the wires on the house side. However, using ladders carries the risk of falling, and aerial work vehicles cannot enter narrow roads, so there are issues with limiting the places where work can be done.

[0003] To address these issues, for example, Patent Document 1 discloses an invention entitled "Feed-in Wire Removal Method, Support Point Hook and Clamp," which relates to work to remove a feed-in wire that has been pulled into a building from a utility pole by work carried out from the ground. The method of removing a drop line disclosed in Patent Document 1 is characterized in that a support point hook is attached to the tip of a base stick, and this support point hook is hooked onto a hook screw or a fastening rack installed on the wall of the building.Furthermore, the tip of a rope passing near the support point hook is connected to a clamp attached to the tip of the work stick, and after tightening the clamp to the drop line, the support point hook and clamp are pulled together by the rope, and the drop line attachment point is cut while the rope is carrying the tension of the drop line. This method allows the work of removing the drop wire to be done on the ground, which dramatically improves worker safety compared to when the work is done at high altitudes. In addition, because a high-altitude lifting device is not required, the cost of the equipment required for the work is reduced.

[0004] Furthermore, Patent Document 2 discloses an invention entitled "High-altitude electric wire cutting tool" that relates to a tool that can cut electric wires safely from the ground. The invention disclosed in Patent Document 2 has a structure that includes a pole that a worker can hold and operate, a cutter that cuts electric wires, a fixing part that fixes the cutter to the pole, a guide that guides the electric wires to the cutter blade, and a wire that pulls the cutter handle from the ground. With this structure, when the pole is operated to guide the electric wire into the cutter blade and the wire is pulled, the electric wire is cut by the cutter blade, allowing workers to easily cut and remove the electric wire while on the ground.

[0005] Furthermore, Patent Document 3 discloses an invention entitled "electric wire cutting tool" that relates to a tool that can reduce the burden on a worker when cutting electric wires. The invention disclosed in Patent Document 3 has a structure including a rotating member having a screw portion with a screw thread and a cylindrical smooth portion located at the end of the screw portion, which rotates in response to the operation of an indirect live line operating rod, a movable member that engages with the screw portion, a support member that is attached so that it can rotate relative to the smooth portion, a first link connected to the movable member via a first joint, a second link connected to the first link via a second joint and to the support member via a fourth joint, and having a first blade at its tip, a third link connected to the movable member via the first joint and extending on the opposite side of the first link across the movable member, and a fourth link connected to the third link via the third joint and to the support member via a fourth joint, and having a second blade facing the first blade. With this structure, the gap between the first blade and the second blade opens in the longitudinal direction of the indirect live-line operating rod, and the first blade and the second blade are arranged facing upward. Therefore, the operator can insert the electric wire between the first blade and the second blade by moving the electric wire cutting tool straight toward the electric wire from his / her hand. Therefore, compared to using conventional tools, the operator can easily insert the electric wire between the pair of blades. Furthermore, because the electric wire cutting tool of the present invention is structured to be attached to the tip of the indirect live-line operating rod, the operator can safely cut the electric wire by operating the indirect live-line operating rod from the ground.

[0006] Patent Document 4 discloses an invention entitled "Remotely Operated Cutter" that relates to a tool that can safely cut electrical wires and other objects placed at high altitudes from the ground in a stable position. The invention disclosed in Patent Document 4 has a structure comprising a shaft body that rotates around its axis integrally with the remote control rod connected to the lower end, two connecting bodies that are installed parallel to the axial direction on this shaft body, at least one of which moves up and down on the shaft body in response to the axial rotation of the remote control rod, a pliers-type cutter section in which one of a pair of handles is swingably connected to each of the two connecting bodies, and an electric wire abutment section that is arranged to move integrally with the cutter section, with the height and protrusion width approximately equal to the intersection of the upper and lower blades of the cutter section and a predetermined distance apart in the lateral direction perpendicular to the height direction and protrusion direction. With this structure, even if the height and protrusion position of the intersection change as cutting progresses, the height and protrusion width of the wire abutting portion also change, and the wire abutting portion abuts against multiple points on the wire in the direction perpendicular to the axis, preventing rotation of the remote control rod and co-rotation. Therefore, by using the tool of the present invention, the wire cutting operation can be performed stably and in a good condition. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Patent Publication No. 2021-158741 [Patent Document 2] Japanese Patent Application Laid-Open No. 2011-254692 [Patent Document 3] Japanese Patent Application Publication No. 2018-126033 [Patent Document 4] Japanese Patent Application Laid-Open No. 2013-198336 Summary of the Invention [Problem to be solved by the invention]

[0008] The invention disclosed in Patent Document 1 is structured so that the drop wire is held with a clamp and tension is maintained on the drop wire using a support point hook, and then the drop wire is cut using an electric cutter.This means that the drop wire cutting work can be carried out safely from the ground, but there is a problem in that the many tools required for the work and the work procedure are complicated, making it difficult to cut the electric wire efficiently. Furthermore, the inventions disclosed in Patent Documents 2 and 3 have a problem in that they do not have a mechanism for fixing the electric wire, making it difficult to cut the electric wire. Furthermore, in the invention disclosed in Patent Document 4, the opening and closing of the cutter section is driven by the rotation of the remote control rod, which means that it takes time to open and close the cutter section, resulting in poor work efficiency when cutting the electric wire or removing the cut electric wire from the cutter section.

[0009] The present invention has been made to address such conventional circumstances, and aims to provide a wire cutting tool that can safely and efficiently cut electric wires installed at high altitudes from the ground. [Means for solving the problem]

[0010] In order to achieve the above object, a first invention is an electric wire cutting tool for cutting an electric wire installed at a high place, comprising an electric wire clamping mechanism having a clamp that is C-shaped in a side view, an electric wire cutting mechanism attached to the clamp, and a connecting mechanism for attaching the clamp to a common operating rod, the clamp comprising an upper jaw and a base that are arranged to face each other, and a connecting part that connects the upper jaw and the base, the electric wire clamping mechanism comprising a lower jaw that is installed in the clamp and clamps an electric wire together with the upper jaw, and the clamp, the electric wire cutting mechanism comprising an upper blade that is fixed to the clamp and has a first cutting part, and a lower jaw that is rotatably connected to the upper blade via a rotating shaft member, and a string-like body having one end connected to the tip of the lower blade. The connecting mechanism comprises a cylindrical connecting fitting having a closed upper end and a common operating rod connected to its lower end, and a lower jaw moving means extending vertically upward from the upper end of the connecting fitting and held by a base so as to be rotatable around the cylindrical axis of the connecting fitting, and which moves the lower jaw forward or backward relative to the upper jaw as the connecting fitting rotates. The electric wire cutting mechanism is characterized in that when the string-like body is pulled, the lower blade rotates in a direction closing relative to the upper blade, and the electric wire is cut by the first blade and the second blade. In the first aspect of the invention, when "the clamp is C-shaped when viewed from the side," it is also intended to include when "the clamp is approximately C-shaped when viewed from the side." In the first invention, when the common operating rod is connected to the connecting fitting and an electric wire is placed in the clamp, operating the common operating rod to rotate the connecting fitting causes the lower jaw to advance relative to the upper jaw, thereby clamping the electric wire between the upper and lower jaws and securing it in the clamp, and when the connecting fitting is rotated in the opposite direction, the lower jaw retracts relative to the upper jaw, thereby releasing the state in which the electric wire is clamped between the upper and lower jaws and releasing the electric wire (i.e., making it possible to remove the electric wire from the clamp).Furthermore, when the electric wire is clamped between the upper and lower jaws, pulling the end of the string-like portion, one end of which is connected to the lower blade, causes the lower blade to close against the upper blade, thereby cutting the electric wire.

[0011] The second invention is characterized in that, in the first invention, it comprises a cylindrical shaft body having a male thread formed on its outer peripheral surface and extending vertically downward from the underside of the lower jaw, the lower jaw movement means consisting of a cylindrical shaft holding portion having a female thread formed on its inner peripheral surface that screws into the male thread of the shaft body, and the lower jaw is provided with a rotation restriction means that engages with the connecting portion to allow movement of the shaft body in the axial direction while restricting rotation of the shaft body around the cylindrical axis. In the second invention, in addition to the effect of the first invention, when the common operating rod is operated to rotate the connecting fitting, the shaft body rotates in the opposite direction without co-rotating with the shaft holding part which rotates integrally with the connecting fitting, resulting in the lower jaw part moving integrally with the shaft body in the axial direction of the shaft body.

[0012] A third invention is characterized in that in the first or second invention, a voltage detector for determining the live state of the electric wire placed in the clamp is placed in the clamp. In addition to the effects of the first or second invention, the third invention has the effect that if the electric wire is in a live state, it is detected by a voltage detector when the electric wire is placed in the clamp.

[0013] The fourth invention is characterized in that, in any of the first to third inventions, the rotating shaft member is installed at the connecting portion, and the connecting portion and the lower jaw portion are respectively provided with a blade passage hole and a blade passage groove so that the lower blade can pass through the interior when it rotates around the rotating shaft member. In the fourth invention, in addition to the effect of any one of the first to third inventions, the electric wire is cut inside the clamp by the upper and lower blades, so that the cutting force of the upper and lower blades is transmitted to the electric wire more efficiently than when the electric wire, which is fixed in a cantilevered state by the upper and lower jaws, is cut by the upper and lower blades installed outside the clamp.

[0014] A fifth invention is characterized in that, in any one of the first to fourth inventions, a spring member is provided that biases the lower blade in a direction that opens relative to the upper blade. In the fifth invention, in addition to the effect of any one of the first to fourth inventions, when the force pulling the string-like body is weakened, the spring force of the spring member causes the lower blade to swing in a direction opening relative to the upper blade.

[0015] The sixth invention is characterized in that, in the fifth invention, the spring member is a compression coil spring having one end connected between the tip and base ends of the lower blade and the other end connected to the connecting portion. In the sixth aspect of the invention, in addition to the effect of the fifth aspect of the invention, the function of the spring member to bias the lower blade in the opening direction relative to the upper blade is achieved with a simple structure.

[0016] The seventh invention is characterized in that, in any of the first to sixth inventions, a pulley is installed at the tip of the lower blade, the string-like body is wound around the pulley, and one end of the string-like body is fixed to the connection part instead of being connected to the tip of the lower blade. In the seventh invention, in addition to the effect of any one of the first to sixth inventions, the tension generated when the other end of the string-like body is pulled is applied to the part where one end of the string-like body is connected to the connection part, and part of this force is applied in the direction of swinging the lower blade. [Effects of the Invention]

[0017] In the first aspect of the present invention, electric wires can be cut by a simple operation of rotating the common operating rod and pulling the string-like body. Furthermore, this operation can be performed while standing on the ground. Therefore, according to the first aspect of the present invention, electric wires installed at high places can be cut safely and efficiently.

[0018] According to the second invention, in addition to the effect of the first invention, the lower jaw moving means can be realized with a simple structure, and therefore the effect of reducing manufacturing costs can be achieved.

[0019] According to the third invention, in addition to the effects of the first or second invention, the worker can know in advance if the electric wire is live, thereby enabling the work of cutting the electric wire to be carried out even more safely.

[0020] According to the fourth invention, in addition to the effects of any of the first to third inventions, the cutting force of the upper and lower blades is efficiently transmitted to the electric wire, thereby reducing the force that the worker needs to apply to the string-like body when cutting the electric wire.

[0021] According to the fifth invention, in addition to achieving the effects of any of the first to fourth inventions, when the force pulling the string-like body is weakened, the lower blade swings in a direction opening relative to the upper blade and quickly retreats from the cutting point of the electric wire, thereby achieving the effect of improving workability when cutting the electric wire.

[0022] According to the sixth invention, in addition to the effect of the fifth invention, the function of the spring member to bias the lower blade in the opening direction relative to the upper blade is realized with a simple structure, thereby achieving the effect of reducing manufacturing costs.

[0023] According to the seventh invention, part of the tension generated at the part where one end of the string-like body is fixed to the connection part acts in a direction that causes the lower blade to swing, thereby further enhancing the effect of the fourth invention, in that the electric wire can be easily cut without the operator having to pull the string-like body hard. [Brief explanation of the drawings]

[0024] [Figure 1] 1 is a side view showing the appearance of an electric wire cutting tool according to an embodiment of the present invention. [Figure 2] 2A and 2B are a view taken in the direction of an arrow A and a cross-sectional view taken in the direction of an arrow BB in FIG. 1, respectively. [Figure 3] (a) and (b) are cross-sectional views taken along the CC line and the DD line of the upper jaw, connecting part, base, lower jaw, shaft body and shaft holder shown in Figure 2(a), respectively, and (c) is a cross-sectional view taken along the EE line in Figure 2(a). [Figure 4] 10(a) and 10(c), and 10(b) and 10(d) are side views and front views, respectively, showing a state in which a lower blade is swingably connected to an upper blade. [Figure 5] 2 is a diagram showing a state in which the string in FIG. 1 is pulled downward to swing the lower blade. FIG. DETAILED DESCRIPTION OF THE INVENTION [Example]

[0025] The structure of the wire cutting tool of the present invention and the actions and effects achieved thereby will be specifically described with reference to Figures 1 to 5. Note that since the wire cutting tool of the present invention is attached to the tip of a common operating rod and used in a state where it is approximately parallel to the vertical direction, the following description uses expressions such as "upper surface," "lower surface," "upper end," and "lower end," assuming the state in which it will actually be used.

[0026] Fig. 1 is a side view showing the appearance of an electric wire cutting tool according to an embodiment of the present invention, and Figs. 2(a) and 2(b) are a view taken in the direction of arrow A and a cross-sectional view taken in the direction of arrow BB in Fig. 1, respectively. Also, Figs. 3(a) and 3(b) are cross-sectional views taken in the direction of arrow CC and the direction of arrow DD in Fig. 2(a), respectively, of the upper jaw, connecting portion, base, lower jaw, shaft, and shaft holder, and Fig. 3(c) is a cross-sectional view taken in the direction of arrow EE in Fig. 2(a). Furthermore, Figs. 4(a) to 4(d) are diagrams for explaining the movement of the lower blade relative to the upper blade, and Fig. 5 is a diagram showing the state in Fig. 1 in which the string is pulled downward to swing the lower blade. In Figures 1, 2(a), 2(b), 4(a), and 4(b), the electric wires are indicated by dashed lines, and the upper blade, lower blade, and pulley are omitted from Figure 2(a). Figures 4(a) and 4(c) are side views showing the state in which the lower blade is pivotally connected to the upper blade, and Figures 4(b) and 4(d) are front views of Figures 4(a) and 4(c), respectively. Figures 4(c) and 4(d) show the state in which the lower blade pivots relative to the upper blade in Figures 4(a) and 4(b), respectively. Furthermore, Figure 5 shows the state in which the electric wire cutting tool is attached to a common operating rod.

[0027] As shown in Figures 1 and 2, the wire cutting tool 1 comprises a wire clamping mechanism 2 having a clamp 2a that is roughly C-shaped when viewed from the side, a wire cutting mechanism 3 and a voltage detector 4 attached to the clamp 2a, and a connecting mechanism 5 for attaching the clamp 2a to a common operating rod S. The voltage detector 4 has the function of determining the live state of the electric wire W placed inside the clamp 2a. The common operating rod S has a cylindrical connecting part 51 disposed at the upper end of a long, insulating rod 50, and a tightening nut 53 is screwed onto a threaded part 52 provided between the rod 50 and the connecting part 51. A pair of pin-shaped engaging protrusions 51a, 51a are provided on the outer circumferential surface of the connecting part 51, symmetrically with respect to the cylindrical axis of the connecting part 51.

[0028] The clamp 2a comprises an upper jaw 6 having a concave lower surface 6a that is convex upward when viewed from the side, a pedestal 7 arranged so that its upper surface 7a faces the lower surface 6a of the upper jaw 6, a connecting portion 8 that connects the upper jaw 6 and the pedestal 7, and a base 9 installed on the lower surface 7b of the pedestal 7. The electric wire clamping means 2 is composed of the clamp 2a and a lower jaw 20 having a male thread formed on its outer circumferential surface and a cylindrical shaft 21 that extends vertically downward from the lower surface 20b. The lower jaw 20 clamps the electric wire W between the upper surface 20a and the lower surface 6a of the upper jaw 6. The wire cutting mechanism 3 comprises an upper blade 10, most of which is installed inside the upper jaw 6 and a part of which is installed inside the connecting part 8, a lower blade 11 swingably connected to the connecting part 8 via a fixing pin 12a, a pulley 13 fixed to a tip 11b of the lower blade 11 by a fixing pin 12c, and a chain 15a, the base end 15a of which is fixed to a fixing part 14 provided at the bottom of the back surface 8a of the connecting part 8, the chain 15a being wound around the pulley 13 and having a connecting ring 16 attached to a tip 15b. It consists of a chain 15, a string 17 whose base end 17a is connected to the tip 15b of the chain 15 via a connecting ring 16, a core material 18 made of a round bar whose base end 18a is swingably connected to the lower blade 11 via a fixing pin 12b and whose tip 18b is loosely inserted into an insertion hole (not shown) provided in the fixed part 14 so as to be able to protrude downward, and a compression coil spring 19 inserted onto this core material 18 and arranged between the fixing pin 12b and the fixed part 14.

[0029] The connecting mechanism 5 consists of a connecting fitting 22 having a cylindrical shape with a closed upper end and an inner diameter set so that the connecting portion 51 of the common operating rod S can be inserted therein, and a cylindrical shaft holding portion 23 extending vertically upward from the upper end 22a of the connecting fitting 22 and having a female thread formed on its inner surface that screws into the male thread of the shaft body 21. The connecting fitting 22 is also provided with an introduction hole 22c extending upward in the axial direction from the lower end 22b, a guide hole 22d extending left and right from the upper end of this introduction hole 22c, and a pair of engagement holes 22e, 22e extending downward in the axial direction from the left and right ends of this guide hole 22d, penetrating from the outer peripheral surface to the inner peripheral surface. The introduction hole 22c, the guide hole 22d, and the pair of engagement holes 22e, 22e are wider than the outer diameter of the engagement protrusion 51a of the common operating rod S, and two sets of them are formed so as to be point-symmetrical with respect to the cylindrical axis of the connecting fitting 22.

[0030] With the pair of engaging projections 51a, 51a of the common operating rod S positioned inside the pair of guide holes 22c, 22c, the connecting portion 51 is inserted into the connecting fixture 22, and when the pair of engaging projections 51a, 51a reach the pair of guide holes 22d, 22d, the common operating rod S is rotated about the central axis so that the pair of engaging projections 51a, 51a are positioned inside the pair of engaging holes 22e, 22e. Then, after moving the tightening nut 53 upward, the tightening nut 53 is rotated in a direction such that the upper end 53a pushes up the lower end 22b of the connecting fixture 22, whereby the electric wire cutting tool 1 is fixed to the common operating rod S.

[0031] As shown in Figure 2(b), the shaft body 21, connecting fitting 22, and shaft holder 23 are arranged coaxially, and through holes 7c and 9b are provided in the pedestal 7 and base 9 to allow communication with the shaft holder 23 and to be parallel to the longitudinal direction of the common operating rod S attached to the connecting fitting 22. That is, the connecting fitting 22 is held rotatably about its cylindrical axis by the pedestal 7 and base 9 with the shaft holder 23 loosely inserted into the through holes 7c and 9b, and when the common operating rod S attached to the connecting fitting 22 is rotated, the shaft holder 23 rotates within the through holes 7c and 9b. The shaft holder 23 has a stepped shape such that the outer diameter of the portion protruding from the upper surface 7a of the pedestal 7 is larger than the inner diameter of the through hole 7c so as to prevent it from slipping out of the through holes 7c and 9b.

[0032] 2(a), 3(a), and 3(b), the upper jaw 6, connecting portion 8, and lower jaw 20 are respectively provided with a blade passage groove 6b, a blade passage hole 8c, and a blade passage groove 20c so that the lower blade 11 can pass through the interior when it rotates around the fixing pin 12a. The upper jaw 6 also has an insertion hole 6c for the fixing pin 12a, and recesses 6d and 6e in which the electroscope 4 and upper blade 10 are respectively placed. Note that if there is no possibility that the lower blade 11 will come into contact with the upper jaw 6 when it rotates, there is no need to provide the upper jaw 6 with the blade passage groove 6b. As shown in FIG. 3(c), the back surface 20d of the lower jaw portion 20 is provided with a guide groove 20e into which a part of the front surface 8b side of the connecting portion 8 can be placed. In this case, a portion of the front surface 8b of the connecting portion 8 is disposed inside the guide groove 20e, and therefore the lower jaw 20 is movable only in the longitudinal direction of the connecting portion 8. The shaft 21, whose upper end is fixed to the underside 20b of the lower jaw 20, moves integrally with the lower jaw 20. Therefore, when the common operating rod S attached to the connecting fitting 22 is operated to rotate the shaft holder 23 in the through-holes 7c, 9b as described above, the shaft 21 rotates in the opposite direction to the shaft holder 23 without co-rotating with the shaft holder 23. On the other hand, the shaft holder 23, which is rotatably held by the base 7, is restricted from moving in the longitudinal direction of the connecting portion 8. Therefore, the lower jaw 20 and the shaft 21 move integrally in a direction parallel to the longitudinal direction of the connecting portion 8. In other words, the guide groove 20e of the lower jaw 20 engages with the connecting portion 8, thereby allowing the shaft body 21 to move in the axial direction while forming a rotation control means that controls the rotation of the shaft body 21 around the cylindrical axis, and the shaft holding portion 23 forms a lower jaw moving means that moves the lower jaw 20 forward or backward relative to the upper jaw 6 in accordance with the rotation of the connecting fitting 22. Therefore, in the electric wire cutting tool 1, by rotating the common operating rod S attached to the connecting fitting 22, it is possible to narrow the gap between the upper jaw 6 and the lower jaw 20 to clamp the electric wire W between the upper jaw 6 and the lower jaw 20, and to widen the gap between the upper jaw 6 and the lower jaw 20 to remove the electric wire W from between the upper jaw 6 and the lower jaw 20. In this way, in the electric wire cutting tool 1, the lower jaw movement means is realized with a simple structure, which makes it possible to reduce manufacturing costs.

[0033] As shown in Figures 4(a) and 4(b), the upper blade 10 and the lower blade 11 are swingably connected via a fixing pin 12a that is fixed so as not to be removed while being inserted into the insertion hole 6c (see Figures 3(a) and 3(b)) of the upper jaw 6. The upper blade 10 and the lower blade 11 are formed with a first cutting edge 10a and a second cutting edge 11a that have a generally arc-shaped cutting edge in a side view at opposing locations. As shown in Figures 4(a) and 4(c), the lower blade 11 has a through hole 11c at the tip 11b for attaching the fixing pin 12c (see Figure 1), and also has a through hole 11d for attaching the fixing pin 12b (see Figure 1). The upper blade 10, which is installed inside the recess 6e of the upper jaw 6 (see FIG. 3(a)), is fixed to the clamp 2a, while the lower blade 11 is swingably connected to the clamp 2a via a fixing pin 12a. That is, in the electric wire cutting tool 1, the fixing pin 12a serves as a rotating shaft member, and the lower blade 11 is rotatably connected to the upper blade 10 via this rotating shaft member. Therefore, when the tip 11b of the lower blade 11 is swung in the direction indicated by arrow F in FIG. 4(a), the lower blade 11 rotates in a direction closing relative to the upper blade 10, as shown in FIGS. 4(c) and 4(d), and the electric wire W is cut by the first blade portion 10a and the second blade portion 11a. If the upper jaw 6, the connecting portion 8, and the lower jaw 20 are not provided with the blade passage grooves 6b, the blade passage holes 8c, and the blade passage grooves 20c, it is conceivable to use a structure in which the upper blade 10 and the lower blade 11 installed outside the clamp 2a cut the electric wire W fixed in a cantilevered state by the upper jaw 6 and the lower jaw 20, for example. However, with such a structure, the cutting force of the upper blade 10 and the lower blade 11 cannot be efficiently transmitted to the electric wire W. In contrast, the electric wire cutting tool 1 is structured so that the electric wire W is cut inside the clamp 2a by the upper blade 10 and the lower blade 11, and the cutting force of the upper blade 10 and the lower blade 11 is efficiently transmitted to the electric wire W, thereby reducing the force that the operator needs to apply to the string 17 when cutting the electric wire W.

[0034] When the string 17 is pulled downward in the electric wire cutting tool 1 in the state shown in FIG. 1, the lower blade 11 swings as indicated by the arrow F in FIG. 4(a), and as a result, the core 18 swings about the fixing pin 12b as the center as shown in FIG. 5, the tip 18b protrudes downward from an insertion hole (not shown) provided in the fixing portion 14, and the compression coil spring 19 is compressed along the core 18. Therefore, when the force pulling the string 17 is reduced, the biasing force of the compression coil spring 19 causes the lower blade 11 to swing in an opening direction relative to the upper blade 10. In other words, in the electric wire cutting tool 1, by reducing the force pulling the string 17 after cutting the electric wire W, the lower blade 11 swings in an opening direction relative to the upper blade 10 and quickly retreats from the cutting portion of the electric wire W, resulting in excellent operability when cutting the electric wire W. According to the electric wire cutting tool 1, the function of applying a biasing force in the direction in which the lower blade 11 opens relative to the upper blade 10 is achieved by a simple structure in which the compression coil spring 19 is fitted onto the core material 18 and installed between the lower blade 11 and the fixed part 14, thereby reducing manufacturing costs. The core material 18 also functions to prevent the compression coil spring 19 from bending when compressed.

[0035] Furthermore, in the electric wire cutting tool 1, the base end 15a is fixed to the fixing part 14 provided below the connecting part 8, and the string 17 is connected via the connecting ring 16 to the tip 15b of the chain 15 that is wound around the pulley 13 installed at the tip 11b of the lower blade 11. Therefore, when the string 17 is pulled, tension generated in the string 17 and the chain 15 is applied to the part where the base end 15a of the chain 15 is fixed to the fixing part 14, and part of this force acts in the direction that swings the lower blade 11 as shown by the arrow F in Figure 4(a). Therefore, with the electric wire cutting tool 1, the operator can easily cut the electric wire W without pulling the string 17 strongly.

[0036] As described above, with the electric wire cutting tool 1, it is possible to cut the electric wire W by performing the simple operation of rotating the common operating rod S and pulling the string 17 from the ground. Therefore, with the electric wire cutting tool 1, it is possible to safely and efficiently cut the electric wire W installed at a high place. Furthermore, in the electric wire cutting tool 1, when a live electric wire W is placed inside the clamp 2a, the voltage detector 4 detects that the electric wire W is live. That is, according to the electric wire cutting tool 1, information that the electric wire W is live is transmitted in advance, allowing the worker to cut the electric wire W safely.

[0037] The electric wire cutting tool of the present invention is not limited to the structure shown in the above-described embodiment. For example, a helical spring may be attached to the fixing pin 12a instead of the compression coil spring 19 as a spring member that biases the lower blade 11 in the direction of closing relative to the upper blade 10. A wire may also be used as a string-like body instead of the chain 15 or the string 17. Furthermore, instead of the string-like body for operating the lower blade 11 being composed of two types of members, the chain 15 and the string 17, it may be composed of only one of the chain 15 and the string 17. Furthermore, a structure may be adopted in which one end of the string-like body is connected to the tip 11b of the lower blade 11 without the pulley 13. [Industrial Applicability]

[0038] The present invention can be used in cases where cutting of electric wires installed at high places needs to be performed from the ground. [Explanation of symbols]

[0039] 1...Wire cutting tool 2...Wire clamping mechanism 2a...Clamp 3...Wire cutting mechanism 4...Voltage detector 5...Connection mechanism 6...Upper jaw 6a...Bottom surface 6b...Blade passing groove 6c...Insertion hole 6d, 6e...Recess 7...Base 7a...Top surface 7b...Bottom surface 7c...Through hole 8...Connection part 8a...Back surface 8b...Front side 8c...Blade passage hole 9...Base 9b...Through hole 10...Upper blade 10a...First blade part 11...Lower blade 11a...Second blade part 11b...Tip 11c, 11d...Through hole 12a~12c...Fixing pin 13...Pulley 14...Fixing part 15...Chain 15a...Base end 15b...Tip 16...Connecting ring 17... String 17a... Base end 18... Core material 18a...Base end 18b...Tip 19...Compression coil spring 20...Lower jaw portion 20a...Upper surface 20b...Lower surface 20c...Blade portion passage groove 20d...Back surface 20e...Guide groove 21...Shaft body 22...Connecting fitting 22a...Upper end 22b...Lower end 22c...Introducing hole 22d...Guide hole 22e...Engagement hole 23...Shaft holding portion 50...Rod 51...Connecting portion 51a...Engagement protrusion 52...Threaded portion 53...Tightening nut 53a...Upper end S...Common operating rod W...Electric wire

Claims

1. A wire cutting tool for cutting wires installed at a high place, a wire clamping mechanism having a clamp that is C-shaped in side view; a wire cutting mechanism attached to the clamp; a connecting mechanism for attaching the clamp to a common operating rod, The clamp includes an upper jaw portion and a base portion arranged to face each other, and a connecting portion connecting the upper jaw portion and the base portion, the wire clamping mechanism includes a lower jaw portion that is installed in the clamp and clamps the wire together with the upper jaw portion; and the clamp; The wire cutting mechanism includes: an upper blade fixed to the clamp and having a first cutting edge; a lower blade rotatably connected to the upper blade via a rotary shaft member, the lower blade having a second blade portion disposed opposite the first blade portion; a string-like body, one end of which is connected to the tip of the lower blade; The connecting mechanism includes: a connecting fitting having a cylindrical body with a closed upper end and a lower end to which the common operating rod is connected; a lower jaw moving means that extends vertically upward from the upper end of the connecting fitting, is held by the base so as to be rotatable about the cylindrical axis of the connecting fitting, and moves the lower jaw forward or backward relative to the upper jaw as the connecting fitting rotates; The wire cutting mechanism is characterized in that when the string-like body is pulled, the lower blade rotates in a direction closing relative to the upper blade, and the wire is cut by the first blade portion and the second blade portion.

2. a cylindrical shaft body having an external thread formed on its outer circumferential surface and extending vertically downward from the lower surface of the lower jaw portion; the lower jaw moving means is made of a cylindrical shaft holding portion having an internal thread formed on an inner circumferential surface thereof, the internal thread of which is engaged with the external thread of the shaft body, The wire cutting tool according to claim 1, characterized in that the lower jaw portion is provided with a rotation restriction means that engages with the connecting portion to allow axial movement of the shaft body while restricting rotation of the shaft body around its cylindrical axis.

3. 3. The electric wire cutting tool according to claim 1, wherein a voltage detector for determining a live wire state of the electric wire installed in the clamp is installed in the clamp.

4. the rotating shaft member is installed in the connecting portion, A wire cutting tool as described in any one of claims 1 to 3, characterized in that the connecting portion and the lower jaw portion are provided with a blade passage hole and a blade passage groove, respectively, so that the lower blade can pass through the interior when rotated around the rotating shaft member.

5. 5. The electric wire cutting tool according to claim 1, further comprising a spring member that biases the lower blade in a direction in which the lower blade opens relative to the upper blade.

6. 6. The wire cutting tool according to claim 5, wherein the spring member is a compression coil spring having one end connected between the tip and base ends of the lower blade and the other end connected to the connecting portion.

7. A pulley is provided at the tip of the lower blade, A wire cutting tool as described in any one of claims 1 to 6, characterized in that the string-like body is wound around the pulley, and the one end of the string-like body is fixed to the connection portion instead of being connected to the tip of the lower blade.

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