Cutter head

Abstract

To provide a cutter head capable of achieving a sufficient insulation.SOLUTION: A cutter head for cutting a cut material to which a voltage is applied by a power supplied from a driving source, comprises: a metal cutting blade 22 having a blade part 22a and a non-blade part 22b communicated with the blade part 22a; and insulation parts 23 and 24 holding the non-blade part 22b. Preferably, in the cutter head, the metal cutting blade 22 is formed in a plate shape, and both surfaces of the non-blade part 22b are nipped by the insulation parts 23 and 24. More preferably, in the cutter head, the cutting blade 22 has a U-like shape, and the blade part 22a is formed on an inner peripheral side of the cutting blade 22, the non-cutting part 22b is formed on an outer peripheral side of the cutting blade 22, and the insulation parts 23 and 24 cover a whole of the outer periphery of the cutting blade 22.SELECTED DRAWING: Figure 9

Description

[Technical Field]

[0001] The present technology relates to a cutter head that cuts an object to be cut, such as an electric wire. [Background technology]

[0002] Conventionally, electric wire cutting devices have been proposed for cutting electric wires during live-line work (see, for example, Patent Document 1). The electric wire cutting device includes an operating rod, a cutter attached to one end of the operating rod, and a gripping lever attached to the other end of the operating rod. By gripping the gripping lever, an operator can safely cut mainly installed electric wires, and can prevent ground faults and short-circuit accidents.

[0003] In some cases, data centers undergo power supply equipment renewal work. During this work, it is necessary to continue supplying power to the servers in the data center, so cables carrying voltage are cut using a cutting device. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2017-28925 Summary of the Invention [Problem to be solved by the invention]

[0005] Trunk cables installed in data centers generally have large diameters and cannot be cut by a worker alone. For this reason, cutting devices powered by secondary batteries, for example, are used to cut the cables. Battery-powered cutting devices can apply greater force than a worker and do not require an external power source, making them easier to install. On the other hand, while devices that use external power sources, such as AC power, are required by standard to have double insulation, the standard for devices powered by secondary batteries does not require double insulation, and the insulation may not be sufficient.

[0006] Furthermore, when cutting the cable, the worker attaches the cutting device directly to the cable and operates it in close proximity to the cable, so to ensure the worker's safety, it is necessary to take measures in advance, such as wearing insulating gloves and laying down an insulating sheet.

[0007] The present disclosure has been made in consideration of the above circumstances, and aims to provide a cutter head that can achieve sufficient insulation. [Means for solving the problem]

[0008] A cutter head according to one embodiment of the present disclosure is a cutter head that cuts an object to be cut by applying a voltage using power supplied from a drive source, and is equipped with a metal cutting blade having a blade portion and a non-blade portion connected to the blade portion, and an insulating portion that holds the non-blade portion.

[0009] In the present disclosure, the non-cutting portion of the cutting blade is held by an insulating portion.

[0010] In a cutter head according to one embodiment of the present disclosure, the cutting blade is plate-shaped, and both sides of the non-blade portion are sandwiched between the insulating portions.

[0011] In the present disclosure, the insulating portion sandwiches the non-blade portion, thereby achieving both insulation and retention of the cutting blade.

[0012] In a cutter head according to one embodiment of the present disclosure, the cutting blade is U-shaped, the blade portion is formed on the inner periphery of the cutting blade, the non-blade portion is formed on the outer periphery of the cutting blade, and the insulating portion covers the entire outer periphery of the cutting blade.

[0013] In the present disclosure, the insulating portion insulates the entire outer periphery of the cutting blade, thereby improving the insulating properties.

[0014] In one embodiment of the cutter head of the present disclosure, the cutting blade is U-shaped, the blade portion is formed on the inner periphery of the cutting blade, and the edge portion of the blade portion is formed so that the object to be cut is positioned in the central portion of the blade portion in the circumferential direction during cutting.

[0015] In the present disclosure, when cutting an object to be cut, force is concentrated on the edge of the blade portion, and damage to the edge can be prevented.

[0016] In a cutter head according to an embodiment of the present disclosure, the dimension between the tip of the blade portion and the insulating portion on one surface side of the cutting blade is longer than the dimension of the insulating portion.

[0017] In the present disclosure, the dimension between the tip of the blade portion and the insulating portion, i.e., the width of the blade portion, is longer than the dimension of the insulating portion, i.e., the width of the insulating portion, thereby improving the strength of the cutting blade.

[0018] A cutter head according to one embodiment of the present disclosure includes a holder that holds the cutting blade, the holder being in contact with the insulating portion but not in contact with the cutting blade.

[0019] In the present disclosure, the holder contacts only the insulating portion, thereby improving the insulation.

[0020] In the cutter head according to one embodiment of the present disclosure, the holder has a fitting groove into which the insulating portion fits.

[0021] In the present disclosure, the insulating portion can be fitted into the fitting groove to ensure secure holding by the holder.

[0022] A cutter head according to one embodiment of the present disclosure includes an insulating cover that covers at least the holder.

[0023] In the present disclosure, the holder is covered with an insulating cover, thereby further improving the insulation.

[0024] The cutter head according to one embodiment of the present disclosure includes a transmission mechanism that transmits power to the cutting blade, and the cover covers the transmission mechanism.

[0025] In the present disclosure, the transmission mechanism can be covered with a cover to further improve insulation. [Effects of the Invention]

[0026] In the cutter head according to one embodiment of the present disclosure, the non-cutting portion of the cutting blade is held by the insulating portion, thereby achieving sufficient insulation. [Brief explanation of the drawings]

[0027] [Figure 1] FIG. [Figure 2] FIG. 2 is a schematic perspective view of a cutter head and a hose. [Figure 3] FIG. 2 is a schematic perspective view of a cutter head and a hose with the cover removed. [Figure 4] FIG. 2 is a schematic front view of the blade unit as viewed from one side. [Figure 5] FIG. 2 is a schematic perspective view of the blade unit as seen from one side. [Figure 6] FIG. 2 is a simplified rear view of the blade unit as seen from one side. [Figure 7] FIG. 2 is a schematic perspective view of the blade unit as seen from the other side. [Figure 8] FIG. 2 is a simplified exploded perspective view of a blade unit. [Figure 9] FIG. 2 is a simplified exploded perspective view of a blade. [Figure 10] FIG. 2 is a schematic perspective view of the blade as viewed from the first insulating portion side. [Figure 11] FIG. 11 is a schematic cross-sectional perspective view taken along line XI-XI in FIG. [Figure 12] FIG. [Figure 13] 13 is a schematic cross-sectional perspective view taken along line XIII-XIII in FIG. 12. FIG. [Figure 14] FIG. 10 is an explanatory diagram illustrating cutting by a cutting device. [Figure 15] FIG. 10 is a simplified reference front view of a blade according to a comparative example. [Figure 16] 16 is a schematic cross-sectional perspective view taken along line XVI-XVI in FIG. 15. [Figure 17]FIG. 10 is an explanatory diagram illustrating cutting by a cutting device according to a comparative example. DETAILED DESCRIPTION OF THE INVENTION

[0028] The present invention will be described below with reference to the drawings showing a cutting device 1 according to an embodiment. Fig. 1 is a schematic front view of the cutting device 1, Fig. 2 is a schematic perspective view of a cutter head 4 and a hose 3, and Fig. 3 is a schematic perspective view of the cutter head 4 and the hose 3 with a cover 6 removed. The cutting device 1 cuts an object to be cut, such as an electric wire to which a voltage is applied, for example, a cable 100 (see Fig. 14). The cross-sectional area and outer diameter of the cable 100 are, for example, 325 mm 2 The cross-sectional area indicates the cross-sectional area of ​​the conductor, and the outer shape indicates the outer shape of the entire cable including the coating. Note that the cross-sectional area and outer shape of the cable 100 are not limited to these. For example, the cross-sectional area may be 325 mm 2 May exceed 325mm 2 The outer diameter may be more than 31 mm or less than 31 mm. The cross-sectional area is 38 to 325 mm. 2 The outer diameter may be in the range of 13 to 31 mm.

[0029] The cutting device 1 includes a hydraulic tool 2, an insulating hose 3, and a cutter head 4. The length of the hose 3 is, for example, 1 m. The length of the hose 3 is not limited to 1 m. The length of the hose 3 is determined taking into consideration the workability in a gap between adjacent cables 100, for example, a gap of approximately 100 mm, the safe distance to be maintained between the worker and the cables 100, the pressure loss that occurs in the hose 3, etc.

[0030] The hydraulic tool 2 accepts operation by an operator to drive the cutter head 4. The hydraulic tool 2 includes, for example, a receiving unit such as a switch or button that accepts operation, a secondary battery, a tank for storing hydraulic oil, a motor powered by the secondary battery, a hydraulic pump driven by the motor, a hydraulic control valve that adjusts the pressure of the hydraulic oil supplied from the hydraulic pump, and a drain pipe for returning the hydraulic oil from the hydraulic control valve to the tank (all of which are not shown). The hydraulic tool 2 is connected to one end of a hose 3 via a fitting 7, and the other end of the hose 3 is connected to the cutter head 4.

[0031] The cutter head 4 has a transmission mechanism 10. The transmission mechanism 10 has, for example, a cylinder 11, a piston housed in the cylinder 11, a link 12 (see Figure 14) connected to the piston, and a biasing member (for example, a spring) that applies force to the piston. The piston and biasing member are not shown. The biasing member applies force to the piston for movement in a second direction, which will be described later. The other end of the hose 3 is connected to one end of the cylinder 11 via a connection box 9 and a joint 8. Two stays 5 protrude in opposite directions from the outer circumferential surface of the other end of the cylinder 11. The stays 5 are not necessarily provided.

[0032] A slot 11a is formed at the other end of the cylinder 11. Two blade units 20, which will be described later, are arranged inside the slot 11a. A support shaft 13 is provided so as to pass through the slot 11a. The support shaft 13 is inserted into a support shaft hole 27 (see FIG. 4) of the blade unit 20. The blade unit 20 is rotatable around the axis of the support shaft 13.

[0033] The motor drives a hydraulic pump, which supplies hydraulic oil from a tank to a hydraulic control valve. When, for example, high-pressure hydraulic oil is supplied from the hydraulic control valve to a cylinder 11 via a hose 3, the piston is driven in a first direction against the biasing force of a biasing member, and a link 12 is driven. The link 12 is connected to two blade units 20, which will be described later. Drive of the link 12 causes the two blade units 20 to rotate around the axis of a support shaft 13, performing a first operation of approaching the workpiece.

[0034] When the hydraulic control valve is operated and the hydraulic oil is returned to the tank, the biasing force of the biasing member exceeds the force due to the pressure of the hydraulic oil, and the biasing force of the biasing member drives the piston in a second direction opposite to the first direction, and also drives the link 12 in the opposite direction. Drive of the link 12 in the opposite direction causes the two blade units 20 to rotate in opposite directions around the axis of the support shaft 13, performing a second operation in which they move away from the workpiece.

[0035] Figure 4 is a simplified front view of the blade unit 20 viewed from one side, Figure 5 is a simplified oblique view of the blade unit 20 viewed from one side, Figure 6 is a simplified rear view of the blade unit 20 viewed from the other side, Figure 7 is a simplified oblique view of the blade unit 20 viewed from the other side, and Figure 8 is a simplified exploded oblique view of the blade unit 20.

[0036] The blade unit 20 has an overall horizontally long rectangular plate shape. The blade unit 20 includes a blade 21, a holder 25, and a fixing portion 32. The holder 25 is made of metal and has a horizontally long rectangular plate shape. The holder 25 has a first long side 25a and a second long side 25b that face each other. A U-shaped recess 26 is formed in the first long side 25a. A fitting groove 26a with an L-shaped cross section, having a bottom surface 26b and a side surface 26c, is formed around the entire inner periphery of the recess 26. The fitting groove 26a is open toward one surface 251 of the holder 25. The one surface 251 of the holder 25 corresponds to one surface of the blade unit 20, and the other surface 252 of the holder 25 corresponds to the other surface of the blade unit 20.

[0037] A through support hole and link hole 28 are formed in one end 25c of holder 25. The support hole is located on the first long side 25a side of holder 25, and link hole 28 is located on the second long side 25b side of holder 25. The support hole is located next to recess 26. At one end 25c of holder 25, the edge shape of holder 25 is formed in an arc shape along each of the support hole and link hole 28, and the overall shape is an S-shape with smoothly connected arcs.

[0038] A recess is formed in the other end 25d of one surface 251 of the holder 25. The recess is recessed toward the other surface 252 of the holder 25 and is formed over the entire other end 25d of the holder 25. An exposure prevention portion 30 having a shape following the recess so as to be flush with the one surface 251 of the holder 25 is provided in the recess. The exposure prevention portion 30 is fixed to the holder 25 by multiple (three in this embodiment) bolts 30a. The exposure prevention portion 30 is made of resin and is a component for preventing exposure of the holder 25. In the second long side portion 25b, multiple (three in this embodiment) insertion holes 29 are lined up along the bottom surface 26b of the recess 26. The insertion holes 29 extend in a direction perpendicular to the plate-shaped holder 25 and penetrate the holder 25.

[0039] The blade 21 has a rectangular plate shape, with a first long side 25a cut out in an arc shape. The overall shape of the blade 21 is U-shaped when viewed from one surface 251 or the other surface 252 of the holder 25. The blade 21 fits into the fitting groove 26a of the holder 25 so that the opening side of the blade 21 coincides with the opening side of the recess 26. The blade 21 is flush with the one surface 251 of the holder 25. The detailed configuration of the blade 21 will be described later.

[0040] The blade 21 is sandwiched between the holder 25 and the fixing portion 32. The fixing portion 32 is made of metal and has an elongated shape. A plurality of (three in this embodiment) screw holes 32a are formed in the fixing portion 32. Each screw hole 32a penetrates the fixing portion 32. The position of each screw hole 32a corresponds to the position of each insertion hole 29. The fixing portion 32 is arranged on one surface 251 of the holder 25, along the bottom surface 26b of the recess 26, so as to straddle both the holder 25 and the blade 21 (more specifically, the second insulating portion 24, described later). The screw holes 32a of the fixing portion 32 and each insertion hole 29 are arranged coaxially. A plurality of (three in this embodiment) bolts 31 are inserted into each insertion hole 29 from the other surface 252 of the holder 25 and screwed into each screw hole 32a. By screwing the bolts 31, the fixing portion 32 and the holder 25 hold the blade 21.

[0041] Fig. 9 is a schematic exploded perspective view of blade 21, Fig. 10 is a schematic perspective view of blade 21 viewed from the first insulating portion 23 side, and Fig. 11 is a schematic cross-sectional perspective view taken along line XI-XI in Fig. 10. Blade 21 includes first insulating portion 23, second insulating portion 24, and cutting blade 22. Each of first insulating portion 23, second insulating portion 24, and cutting blade 22 is plate-like and U-shaped.

[0042] The cutting blade 22 is made of metal and includes a cutting portion 22a, a non-blade portion 22b, and a wall 22c. The cutting blade 22 may be made of a non-conductive material other than metal, such as ceramic. The non-blade portion 22b is shaped like a horseshoe plate. A wall 22c protrudes from substantially the entire inner periphery of the non-blade portion 22b, and is substantially perpendicular to one surface 22ba of the non-blade portion 22b. The wall 22c includes an arc portion 22ca and a linear portion 22cb extending from one end of the arc portion 22ca. The angle formed between the arc portion 22ca and the linear portion 22cb on the inside of the non-blade portion 22b is an obtuse angle less than 180 degrees. The linear portion 22cb is formed on one end side of the non-blade portion 22b, i.e., on one end 22d side of the cutting blade 22. The other end of the non-cutting portion 22b, that is, the other end 22e of the cutting blade 22, does not have a wall 22c.

[0043] The blade portion 22a extends obliquely from the entire arc portion 22ca at the protruding end of the wall 22c toward the inside of the non-blade portion 22b. That is, the blade portion 22a is formed on the inner periphery of the cutting blade 22, sandwiching the wall 22c therebetween, and the non-blade portion 22b is formed on the outer periphery of the cutting blade 22, sandwiching the wall 22c therebetween. The blade portion 22a only needs to extend from at least the arc portion 22ca, and may also extend from portions other than the arc portion 22ca, such as the linear portion 22cb. As the blade portion 22a extends toward the inside of the non-blade portion 22b, it inclines toward the other surface 22bc of the non-blade portion 22b, i.e., toward the opposite side of the wall 22c. In a direction perpendicular to the non-blade portion 22b, the tip of the blade portion 22a extends to a position away from the other surface 22bc of the non-blade portion 22b. A groove 22f having an L-shaped cross section is formed by the other surface 22bc of the non-blade portion 22b and the tip portion of the blade portion 22a. The groove 22f is not formed at one end 22d of the cutting blade 22. The blade portion 22a and the wall 22c are not formed at the other end 22e of the cutting blade 22. Therefore, only the non-blade portion 22b is provided at the other end 22e of the cutting blade 22, and the groove 22f is not formed.

[0044] The first insulating portion 23 is made of a resin material and has insulating properties. The first insulating portion 23 is located on the side of one surface 22ba of the non-blade portion 22b, opposite the blade portion 22a across the wall 22c, i.e., outside the wall 22c. The first insulating portion 23 covers the one surface 22ba of the non-blade portion 22b and at least a portion of the outer peripheral surface of the non-blade portion 22b. The first insulating portion 23 covers the entire outer peripheral surface of the non-blade portion 22b in the area where the groove 22f is formed. The one end 23a of the first insulating portion 23 covers a portion of the outer peripheral surface of the non-blade portion 22b at the one end 22d of the cutting blade 22 where the groove 22f is not formed. The other end 23b of the first insulating portion 23 covers the entire outer peripheral surface of the non-blade portion 22b and the entire end face of the end of the non-blade portion 22b at the other end 22e of the cutting blade 22 where the groove 22f is not formed.

[0045] The second insulating portion 24 is made of a resin material and has insulating properties. The second insulating portion 24 is disposed on the other surface 22bc side of the non-blade portion 22b. The portion of the second insulating portion 24 corresponding to the area where the arc portion 22ca is formed, i.e., the portion corresponding to the area where the groove 22f is formed, fits into the groove 22f. One end 24a of the second insulating portion 24 covers a part of the outer peripheral surface at one end 22d of the cutting blade 22. At one end 22d of the cutting blade 22, the one end 24a of the second insulating portion 24 covers the other part of the outer peripheral surface of the non-blade portion 22b (the part not covered by the first insulating portion 23). At the other end 22e of the cutting blade 22, the other end 24b of the second insulating portion 24 covers the other surface 22bc of the non-blade portion 22b.

[0046] Both surfaces of the cutting blade 22 are sandwiched between the first insulating portion 23 and the second insulating portion 24. The cutting blade 22, the first insulating portion 23, and the second insulating portion 24 are bonded to one another with an adhesive. As described above, the first insulating portion 23 and the second insulating portion 24 cover the entire outer peripheral surface of the cutting blade 22, so that the outer peripheral surface of the metal cutting blade 22 is not exposed and is insulated. As described above, the blade 21 fits into the fitting groove 26a of the holder 25. The blade 21 is positioned in the fitting groove 26a so that the first insulating portion 23 faces the bottom surface 26b of the fitting groove 26a. The width of the bottom surface 26b of the fitting groove 26a is equal to or less than the radial width of the first insulating portion 23. The width of the side surface 26c of the fitting groove 26a is approximately the same as the thickness of the first insulating portion 23 and the second insulating portion 24. That is, the first insulating portion 23 and the second insulating portion 24 are fitted into the fitting groove 26a, and the metal cutting blade 22 does not contact the fitting groove 26a. That is, the holder 25 is in contact with the first insulating portion 23 and the second insulating portion 24 but is not in contact with the cutting blade 22, so that the cutting blade 22 and the holder 25 are insulated from each other. As shown in FIG. 4, the metal fixing portion 32 faces the second insulating portion 24 but does not face the cutting blade 22. That is, the fixing portion 32 does not contact the cutting blade 22. Therefore, the cutting blade 22 and the fixing portion 32 are insulated from each other.

[0047] The cover 6 will now be described. As shown in Figures 1 and 2, the cutting device 1 is equipped with the cover 6. The cover 6 is equipped with a first cover portion 6a that covers the cylinder 11 and support shaft 13 of the transmission mechanism 10, a second cover portion 6b that covers the connection box 9 and joint 8, a third cover portion 6c that covers at least a portion of the holder 25 on one surface of the blade unit 20, and a fourth cover portion 6d that covers at least a portion of the holder 25 on the other surface of the blade unit 20. The cover 6 covers at least the portions that an operator comes into contact with during cutting work, thereby providing insulation between the operator and the object to be cut.

[0048] After placing the cutter head 4 on the workpiece, the operator operates the hydraulic tool 2 and begins cutting. An insulating hose 3 is interposed between the hydraulic tool 2 and the cutter head 4, and hydraulic oil has high insulating properties, allowing the cutting device 1 to more reliably insulate the operator from the workpiece. By making the hose 3 longer than a predetermined length, for example 1 meter, the operator can be positioned away from the workpiece to which voltage is applied during cutting. The string-like hose 3 is also easily deformed, making it easy to work in complex spaces.

[0049] Note that a signal output unit and an optical fiber cable may be used instead of the hydraulic tool 2 and hose 3. The signal output unit outputs an operation signal for driving the transmission mechanism 10, and the optical fiber cable transmits the operation signal to the drive source of the transmission mechanism 10. The optical fiber cable is made of quartz glass or a resin material, etc., and has high insulating properties, and like the hose 3, can more reliably insulate the worker from the workpiece. Furthermore, by making the optical fiber cable longer than a predetermined length, the worker can be positioned away from the workpiece to which voltage is applied during cutting. Furthermore, the optical fiber cable is string-like and easily deforms, making it easy to work in complex spaces.

[0050] FIG. 12 is a schematic front view of the blade 21, and FIG. 13 is a schematic cross-sectional perspective view taken along line XIII-XIII in FIG. 12. As shown in FIG. 12, the edge of the blade portion 22a, i.e., the vertex T1 of the arc-shaped cutting edge, is located slightly closer to the other end 22e than the center of the cutting edge. That is, it is located approximately at the center of the cutting edge. Near the vertex T1, the radial width B1 of the blade portion 22a (the dimension between the tip of the blade portion 22a and the second insulating portion 24) is longer than the radial width A1 of the second insulating portion 24 (the dimension of the second insulating portion 24). Therefore, as shown in FIG. 13, the volume of the blade portion 22a is larger than that of the second insulating portion 24, and the strength is higher. As shown in FIG. 13, if the inclination angle of the blade portion 22a is θ, the inclination angle θ increases from the vertex T1 toward the other end 22e. Therefore, during cutting, the pressure acting on the object to be cut at the apex T1 (pressure acting on the inclined surface of the blade portion 22a) is smaller than the pressure acting on the other end portion 22e.

[0051] 14 is an explanatory diagram illustrating cutting by the cutting device 1. As described above, the cutting device 1 uses two blade units 20. The two blade units 20 are used with their front and back reversed. That is, when one side of one blade unit 20 faces forward, the other side of the other blade unit 20 faces forward.

[0052] As described above, the transmission mechanism 10 has the link 12. As shown in Figure 14, the link 12 is bifurcated, with two protrusions 12a formed at the tip of the bifurcated link. One protrusion 12a is inserted into the link hole 28 of one blade unit 20, and the other protrusion 12a is inserted into the link hole 28 of the other blade unit 20. A support shaft 13 (see Figure 3) is inserted into each support hole of the two blade units 20. Each blade unit 20 is rotatable around the axis of the support shaft 13.

[0053] The cutting device 1 cuts a cable 100, such as an electric wire to which a voltage is applied. Note that the cable 100 is an example of an object to be cut, and the object to be cut is not limited to this. Figure 14 shows the state after the first operation of approaching the cable 100. Due to the shape of the cutting edge, the cable 100 is located near the apex T1 when cutting begins. As the cutting progresses, the cable 100 moves toward the support shaft 13, where a greater force is applied. Furthermore, as described above, the volume of the blade portion 22a is larger than the second insulating portion 24, and the strength is high, making the cutting edge even less susceptible to damage.

[0054] FIG. 15 is a simplified reference front view of a blade 201 according to a comparative example, and FIG. 16 is a simplified cross-sectional perspective view taken along line XVI-XVI in FIG. 15. The configuration of the blade 201 is essentially similar to that of the blade 21. Therefore, the same components as those of the blade 21 are designated by the same reference numerals and will not be described in detail. The blade 201 includes a cutting edge 221 and a second insulating portion 241. The blade 201 has the same configuration as the blade 21 except for the cutting edge 221 and the second insulating portion 241. As shown in FIG. 15, the apex T2 of the cutting edge of the comparative example is located closer to the other end 22e of the cutting edge 221 than the apex T2. That is, it is located on the other end 22e side. Near the apex T2, the radial width B2 of the blade portion 221a is shorter than the radial width A2 of the second insulating portion 241. Therefore, as shown in FIG. 16, the volume of the blade portion 221a is smaller than that of the second insulating portion 241, resulting in lower strength.

[0055] FIG. 17 is an explanatory diagram illustrating cutting by the cutting device 1 according to a comparative example. FIG. 17 shows the state after the first operation of approaching the cable 100 has been performed. Due to the shape of the cutting edge, the cable 100 is located near the apex T2 when cutting begins. As cutting progresses, the cable 100 moves toward the support shaft 13, where a greater force is applied. The area near the apex T2 is closer to the support shaft 13 than the apex T1. As a result, the cable 100 tends to move toward the other end 22e, which tends to concentrate loads at specific points on the other end 22e side of the cutting edge, making the cutting edge more susceptible to damage. Furthermore, as described above, the volume of the cutting edge 221a is smaller than that of the second insulating portion 241, and the strength is lower, making the cutting edge even more susceptible to damage.

[0056] In the cutting device 1 according to the embodiment, the non-blade portion 22b of the cutting blade 22 is sandwiched and held between the first insulating portion 23 and the second insulating portion 24, thereby achieving both insulation and holding of the cutting blade 22. The first insulating portion 23 and the second insulating portion 24 also insulate the entire outer periphery of the cutting blade 22, improving insulation. Furthermore, when cutting an object, force is concentrated on the end of the blade portion 22a, i.e., the cutting edge, which can be prevented from being damaged.

[0057] Furthermore, the dimension between the tip of blade portion 22a and the insulating portion, i.e., the width of blade portion 22a, is longer than the dimension of the insulating portion, i.e., the width of the insulating portion, thereby improving the strength of cutting blade 22. Furthermore, since holder 25 contacts only first insulating portion 23 and second insulating portion 24, insulation can be improved.

[0058] Furthermore, first insulating portion 23 and second insulating portion 24 can be fitted into fitting groove 26a, thereby ensuring secure holding by holder 25. Furthermore, holder 25 can be covered with insulating cover 6, thereby further improving insulation. Furthermore, power transmission mechanism 10 can be covered with cover 6, thereby further improving insulation.

[0059] Furthermore, the insulating hose 3 is interposed between the cutter head 4 and the hydraulic tool 2, thereby achieving insulation between the operator and the workpiece. Furthermore, highly insulating hydraulic oil flows through the hose 3, ensuring insulation between the operator and the workpiece. Furthermore, by making the hose 3 longer than a predetermined length, the operator can be positioned away from the workpiece to which voltage is applied during cutting. Furthermore, a highly insulating optical fiber cable made of quartz glass, resin, or the like is interposed between the cutter head 4 and the signal output unit, ensuring insulation between the operator and the workpiece. Furthermore, by making the optical fiber cable longer than a predetermined length, the operator can be positioned away from the workpiece to which voltage is applied during cutting.

[0060] The embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive. The technical features described in each embodiment can be combined with each other, and the scope of the present invention is intended to include all modifications within the scope of the claims and the scope equivalent to the claims. [Explanation of symbols]

[0061] 1 cutting device 4 cutter head 6 Cover 10 Transmission Mechanism 22 Cutting blade 22a Blade part 22b Non-blade part 23 First insulation section 24 Second insulating section 25 Holder 26a Fitting groove

Claims

1. A cutter head that cuts an object to be cut by applying a voltage using power supplied from a drive source, a metal cutting blade having a cutting portion and a non-cutting portion connected to the cutting portion; an insulating portion that holds the non-blade portion; A cutter head comprising:

2. The cutting blade is plate-shaped, The insulating portion sandwiches both sides of the non-blade portion. The cutter head according to claim 1 .

3. The cutting blade is U-shaped, The blade portion is formed on the inner peripheral side of the cutting blade, The non-cutting portion is formed on the outer periphery of the cutting blade, The insulating portion covers the entire outer periphery of the cutting blade. The cutter head according to claim 1 or 2.

4. The cutting blade is U-shaped, The blade portion is formed on the inner peripheral side of the cutting blade, The edge portion of the blade is formed so that the object to be cut is located at the center portion of the blade in the circumferential direction during cutting. The cutter head according to claim 1 or 2.

5. The dimension between the tip of the blade portion and the insulating portion on one side of the cutting blade is longer than the dimension of the insulating portion. A cutter head according to any one of claims 1 to 4.

6. a holder for holding the cutting blade; The holder is in contact with the insulating portion and is not in contact with the cutting blade. A cutter head according to any one of claims 1 to 5.

7. The holder has a fitting groove into which the insulating portion fits. The cutter head according to claim 6.

8. An insulating cover is provided to cover at least the holder. A cutter head according to claim 6 or 7.

9. a transmission mechanism for transmitting power to the cutting blade; The cover covers the transmission mechanism. The cutter head according to claim 8.

Images