Disk cover and cutting device comprising the same

Abstract

To provide a disk cover and a cutting device capable of collecting properly, cooling waste liquid including grinding chip ground by a cutting wheel.SOLUTION: A disk cover comprises: a cover body 121 which has a cut opening end 123 and a shaft opening 133 to which a drive shaft 11 faces, and covers a cutting wheel 20 for forming a shield space 122; an outer cover 124 which has a contact opening end 124a, covers the cover body 121 and forms a suction space 125; and a suction joint part 126 which is provided on the outer cover 124, has a communication hole 141 communicated with the suction space 125 and has a suction hole 142 for sucking air. The contact opening end 124a contacts a cutting object S, and the cut opening end 123 forms, between itself and the cutting object S, a channel 139 for suction.SELECTED DRAWING: Figure 12

Description

[Technical field]

[0001] The present invention relates to a disk cover that is provided in a cutting device that cuts an object while supplying a coolant to a rotating cutting wheel, and that covers the cutting wheel with the cutting side open, and to a cutting device equipped with the disk cover. [Background technology]

[0002] 2. Description of the Related Art Conventionally, as this type of cutting device, a device that cuts an object to be cut by a rotary blade having through holes therein for a cooling medium is known (see Patent Document 1). This device comprises a drive shaft with a rotating blade fitted at its tip and a hollow portion serving as a fluid flow path, a manifold through which the drive shaft passes in a watertight and rotatable manner, and a liquid supply source which supplies a cooling medium to the manifold via a conduit. The cooling medium from the supply source is supplied to the manifold through a conduit. In the manifold, the cooling medium is supplied from the manifold-side open end to the fluid flow passage of the rotating drive shaft, and further supplied to the through-holes of the rotary blade from the open end of the rotary blade formed at the tip. The cooling medium that flows into the rotary blade is supplied to the blade portion through the through-holes and holes. The cooling medium ejected from the blade portion flushes the cutting chips out of the cutting area, and the blade portion is cooled, preventing deterioration of the rotary blade. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Utility Model Application Publication No. 64-42108 Summary of the Invention [Problem to be solved by the invention]

[0004] In such conventional devices that perform cutting using a rotary blade, the cooling medium is appropriately supplied to the rotating drive shaft and the rotary blade, but the recovery of cutting chips and used cooling medium is not taken into consideration. In other words, although the cutting medium can be efficiently ground by supplying the cooling medium, there is no means for recovering the cutting chips and cooling medium (waste cooling liquid), so there is a problem that it is time-consuming to recover the waste cooling liquid that flows out. However, it is conceivable to provide a disk cover such as a dust cover that covers the rotary blade, and to suck and collect the waste cooling liquid through this disk cover. However, this type of disk cover needs to be in constant contact with the object even if the cutting depth of the rotary blade into the object changes. For this reason, the side opening of the disk cover facing the drive shaft must be large enough to accommodate the cutting depth. Therefore, even if air is sucked from inside the disk cover, it is expected that there will be an extremely large amount of air leaking from the side opening, making it difficult to suck and collect the waste cooling liquid.

[0005] An object of the present invention is to provide a disk cover capable of properly recovering waste cooling liquid mixed with grinding debris produced by a cutting wheel, and a cutting device equipped with the same. [Means for solving the problem]

[0006] The disk cover of the present invention is provided on a cutting device which cuts an object to be cut while supplying a cooling liquid to a cutting wheel attached to a drive shaft, and is a disk cover which covers the cutting wheel with the incision side open, and is equipped with: a cover body which has an incision open end on the incision side and an opening for the drive shaft facing the cutting wheel, and which covers the cutting wheel to form a shielded space; an outer cover which has a contact open end on the incision side, which covers the periphery of the incision open end side of the cover body and forms a suction space between the cover body; and a suction joint part which is attached to the outer cover, and has a communication port at one end which communicates with the suction space and a suction port at the other end for air-suctioning waste cooling liquid associated with grinding, and is characterized in that the contact open end comes into contact with the object to be cut, and the incision open end forms a flow path for suction between the object to be cut and the incision open end.

[0007] According to this configuration, when a cutting wheel is attached to the cutting device and a workpiece is cut while supplying a cooling liquid, a mixture of grinding chips and cooling liquid is generated at the cutting point. Meanwhile, when air suction is performed through the suction port of the suction joint, the suction space between the cover body and the outer cover becomes negative pressure. The cover body faces the cutting point, and the cooling waste liquid generated at the cutting point is sucked into the suction space through the flow path gap of the cut open end facing the workpiece. That is, when the suction space becomes negative pressure, the cooling waste liquid rides on the air flowing in from the shaft opening, passes through the cut open end of the cover body, and flows into the suction space, and is further sucked out by air from the suction port of the suction joint. In this way, a suction space is formed outside the shielded space formed by the cover body, and the waste cooling liquid is sucked in from the cut-out open end of the cover body, so that the waste cooling liquid can be sucked in by air leaking from the shaft opening. Also, the waste cooling liquid generated in the shielded space of the cover body does not leak out beyond the outer cover. Therefore, the waste cooling liquid can be sucked in efficiently and appropriately collected.

[0008] In this case, the cover body has a bottom cover portion having a cut-out open end formed therein, a top cover portion joined to the bottom cover portion and formed so that an opening for the shaft is divided between the bottom cover portion and the top cover portion, and a cover joint portion for joining the top cover portion to the bottom cover portion, and it is preferable that the bottom cover portion, the cover joint portion and the outer cover are formed as a single unit.

[0009] According to this configuration, the lower cover element, which is an integral part of the bottom cover part, cover joint part and outer cover, and the upper cover element, which is the top cover part, are vertically divided into two parts, so that even if the structure is complicated, it can be manufactured relatively easily. Also, in this two-part structure, the top cover part is formed so as to divide the shaft opening between it and the bottom cover part, so that no interference occurs between the work of attaching and detaching the cutting wheel to and from the cutting device (drive shaft) and the work of attaching and detaching the disc cover, and these operations can be performed smoothly.

[0010] In this case, it is preferable that the top cover portion is made of plastic, and the bottom cover portion, the cover joint portion and the outer cover are integrally formed of rubber.

[0011] With this configuration, by making the component that comes into contact with the workpiece out of rubber, the outer cover in particular can be brought into contact with the workpiece without leaving any gaps, thereby minimizing air leakage when sucking up the waste cooling liquid.

[0012] In this case, it is preferable that the top cover portion is plug-joined to the cover joint portion.

[0013] According to this configuration, the top cover portion and the bottom cover side can be easily attached and detached, and the cutting wheel can be easily replaced, for example.

[0014] Further, it is preferable that the outer cover is provided with a position indicator member for indicating the position of the cutting wheel in the left-right direction.

[0015] According to this configuration, the position indicator member indicates the left and right positions of the cutting wheel covered by the disk cover, and by using the position indicator member as a guide, it is possible to cut into the workpiece with high precision.

[0016] On the other hand, it is preferable that the total cross-sectional area of ​​the flow passage for suction is smaller than the cross-sectional area of ​​the suction port.

[0017] With this configuration, the flow rate in the suction flow path (the gap between the open end of the cut and the workpiece) can be made sufficiently faster than the flow rate on the device side that air-sucks the waste cooling liquid, allowing the waste cooling liquid to be sucked in efficiently.

[0018] In addition, two shaft openings are formed in the cover body, located on either side of the cutting wheel, and the cover further includes a first inflow suppression member and a second inflow suppression member which respectively suppress the amount of air flowing in from the two shaft openings when air is sucked into the waste cooling liquid, and it is preferable that the first inflow suppression member and the second inflow suppression member each face the two shaft openings from the inside of the cover body.

[0019] According to this configuration, the first inflow suppression member and the second inflow suppression member suppress (control) the amount of air flowing in from the two shaft openings, respectively, which creates a sufficient negative pressure in the suction space, allowing the waste cooling liquid to be efficiently sucked in by air.

[0020] It is also preferable that the cutting tool further comprises an unevenness attachment that absorbs unevenness in the object to be cut, the unevenness attachment defining an internal space communicating with the shielded space and the suction space, and being removably attached to the outer cover.

[0021] According to this configuration, even if the surface of the workpiece to be cut is uneven, the unevenness can be absorbed by using the uneven attachment, and the waste cooling liquid can be appropriately sucked and collected.

[0022] The cutting device of the present invention is a cutting device that cuts an object to be cut while supplying a coolant to a cutting wheel attached to a drive shaft, and is characterized in that it comprises a motor having a drive shaft on which the cutting wheel is attached, an apparatus body that incorporates the motor with the drive shaft exposed, an attachment unit that attaches the cutting wheel to the drive shaft and has a supply port for supplying coolant to the cutting wheel, and the above-mentioned disc cover.

[0023] According to this configuration, the cutting wheel is attached to the drive shaft of the motor, and the cutting wheel is rotated to cut the object. At that time, by supplying a cooling liquid from the outside to the cutting wheel via the attachment unit, it is possible to avoid the thermal influence during cutting, and the object can be cut efficiently. In addition, the cooling waste liquid generated during cutting can be efficiently sucked through the disk cover, and the cooling waste liquid can be appropriately collected.

[0024] In this case, it is preferable that the device further includes a cover holder for holding the disc cover on the device body, and that the cover holder has a body mounting portion fixed to the device body, a holder guide portion connected to the body mounting portion and for holding the disc cover so that it can slide freely in the cutting direction of the cutting wheel, and a spring mechanism for biasing the disc cover toward the cutting side.

[0025] According to this configuration, the disk cover is slidably held on the body mounting part fixed to the device body via the holder guide part, and is biased toward the cutting side by the spring mechanism, so that the open end (contact open end) of the disk cover can be kept in contact with the workpiece even if the cutting depth of the cutting wheel changes. In other words, even if the cutting depth of the cutting wheel changes during the cutting operation, appropriate collection of waste cooling liquid can be stably performed.

[0026] In this case, it is preferable that the holder guide portion further allows the disc cover to rotate, and that the spring mechanism has a crank plate that engages with the disc cover to press it downward, and a coil spring that urges the disc cover downward via the crank plate.

[0027] In addition, it is preferable that the holder guide portion is formed with a circular sliding guide portion on which the drive shaft faces coaxially, the cover body is formed with an oval shaft opening, and the disc cover is slidably engaged with the sliding guide portion via the shaft opening.

[0028] During cutting work, it is preferable that the axis of the workpiece to be cut and the axis of the device body are parallel, but in the actual cutting work, this angle varies. According to these configurations, since the sliding guide portion is circular, even if the angle between the object to be cut and the device body changes, the open end (contact open end) of the disk cover can be kept in contact with the object to be cut at all times. In other words, even if the angle between the object to be cut and the device body changes during the cutting operation, the waste cooling liquid can be appropriately and stably collected.

[0029] On the other hand, it is preferable that the drive shaft comprises a rotation-preventing shaft portion and a male threaded shaft portion coaxially protruding from the end face of the rotation-preventing shaft portion, and the mounting unit further comprises an inner flange that engages with the rotation-preventing shaft portion and receives the cut-off wheel, a lock nut that screws into the male threaded shaft portion and clamps the cut-off wheel between it and the inner flange, and a supply joint portion that supplies coolant to the cut-off wheel via the lock nut, and the lock nut has an internal flow path for supplying coolant to the cut-off wheel, and the supply joint portion has a connecting shaft portion with an axial flow path communicating with the internal flow path, and a rotation-permitting portion that surrounds the connecting shaft portion and has an annular liquid reservoir that connects to the axial flow path from the radial direction, and a coolant supply port that communicates with the annular liquid reservoir.

[0030] According to this configuration, the cut-off wheel can be securely attached (mounted) to the drive shaft with the cut-off wheel sandwiched between the inner flange and the lock nut. In this state, coolant can be supplied to the cut-off wheel from the supply joint through the lock nut. In this case, the coolant is supplied from the annular liquid reservoir communicating with the supply port to the axial flow path of the connecting shaft and then to the internal flow path of the lock nut, so that the coolant can be smoothly supplied from the rotation-permitting portion to the rotating lock nut and the cut-off wheel. [Brief description of the drawings]

[0031] [Figure 1] FIG. 1 is an external perspective view of a cutting device according to an embodiment. [Diagram 2]FIG. 2 is a perspective view of the cutting device with the disc cover removed. [Diagram 3] 1A and 1B are diagrams showing the structure of a cutting wheel, in which FIG. [Figure 4] 1A and 1B are diagrams showing the structure of a first substrate in a cutting grindstone, in which FIG. [Diagram 5] 4A and 4B are diagrams showing the structure of a second substrate in the cutting grindstone, in which FIG. 4A is a back view and FIG. [Figure 6] FIG. 4 is a half-cut side view of a mounting unit for mounting a cut-off wheel. [Figure 7] FIG. 4 is an exploded side view of a mounting unit for mounting a cutting wheel. [Figure 8] 4A, 4B, and 4C are a front view, a side view, and a back view, respectively, of an inner flange in the mounting unit. [Figure 9] 4A, 4B, and 4C are a front view, a side view, and a rear view, respectively, of a lock nut in the mounting unit. [Figure 10] 1A is a side view, FIG. 1B is a back view, and FIG. 1C is a bottom view of the joint body in the coolant joint portion. [Figure 11] 4A is a front view, FIG. 4B is a side view, and FIG. 4C is a back view of a connecting male screw member in a coolant joint portion. [Figure 12] FIG. 2 is a side view of the disc cover according to the embodiment. [Figure 13] 1A and 1B are a side view and a bottom view of a top cover of the disc cover. [Figure 14] 1A and 1B are a plan view and a side view of a bottom unit of a disc cover. [Figure 15] FIG. 13 is an exploded side view of a disc cover according to a modified example. [Figure 16] 4 is a schematic cross-sectional view for explaining the function of the outer cover and its surroundings. FIG. [Figure 17] FIG. 4 is a plan view of the first and second inflow suppression members including the disc cover. [Figure 18]FIG. 4 is an exploded plan view of the first and second inflow suppression members and their surroundings. [Figure 19] FIG. 11 is a plan view of the periphery of first and second inflow suppression members according to a modified example. [Figure 20] FIG. 11 is an exploded plan view of the periphery of first and second inflow suppression members according to a modified example. [Figure 21] FIG. 2 is a side view of the disc cover with the unevenness attachment attached. [Figure 22] FIG. 2(a) is a plan view and (b) is a side view of the uneven attachment. [Figure 23] 1A, 1B and 1C are diagrams of a cover holder for attaching a disc cover, showing a front view, a side view and a plan view, respectively. [Figure 24] 1A is a diagram of a spring mechanism in a cover holder, and FIG. 1B is a side view of the spring mechanism when the disc cover is in a home position, and FIG. [Diagram 25] 5A and 5B are explanatory diagrams showing the relationship between the disc cover and a spring mechanism. [Figure 26] 10A, 10B, and 10C are views of a cover holder according to a modified example and a front view, a side view, and a plan view, respectively. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0032] With reference to the attached drawings, a disk cover according to an embodiment of the present invention and a cutting device equipped with the same will be described. This cutting device has the basic form of a disk grinder, and is equipped with a cutting wheel that is a disk, and cuts concrete, mortar, tiles, etc. by grinding. The cutting wheel of the embodiment has a coolant flow path inside, and the cutting device has a function of supplying coolant to the cutting wheel and a function of collecting coolant waste liquid mixed with grinding powder when cutting an object. For this reason, although not shown in the figure, a coolant supply device and a coolant waste liquid recovery device are connected to the cutting device. In addition, a special disk cover is provided to cover the cutting wheel as a structure for collecting coolant waste liquid.

[0033] [Cutting device] Fig. 1 is an external perspective view of a cutting device according to an embodiment. Fig. 2 is an external perspective view of the cutting device with a disk cover removed. As shown in these figures, the cutting device 10 has the basic form of a so-called disk grinder in which a drive shaft 11 for mounting a cutting wheel 20 (disk) is exposed, and includes a motor 12 having the drive shaft 11, a device body 13 incorporating the motor 12, a mounting unit 14 for mounting the cutting wheel 20 on the drive shaft 11 and having a supply port 15 for supplying a coolant to the cutting wheel 20, and a disk cover 16 for covering the cutting wheel 20.

[0034] The cutting device 10 also includes a cover holder 17 for holding the disc cover 16 on the device body 13, and an anti-rotation arm 18 for preventing a part of the mounting unit 14 from rotating. A cooling liquid supply device (not shown) is connected to the mounting unit 14 of the cutting device 10 configured as described above via a liquid supply tube 21, and a cooling waste liquid recovery device (not shown) is connected to the disc cover 16 via a waste liquid tube 22, as will be described in detail later.

[0035] The device body 13 incorporating the motor 12 is cylindrical as a handheld power tool, with a disk mounting base 24 disposed at the tip end and the drive shaft 11 protruding from the center of the disk mounting base 24. A power cord 25 is connected to the base end of the device body 13. The power cord 25, the liquid supply tube 21 and the liquid waste tube 22 are bundled together so as not to interfere with work.

[0036] [Cutting wheel] Fig. 3 is a structural diagram of the cutting wheel, Fig. 4 is a structural diagram of the first substrate of the blade substrate, and Fig. 5 is a structural diagram of the second substrate of the blade substrate. As shown in these figures, the cutting wheel 20 is a so-called diamond wheel, and includes a disk-shaped blade substrate 31 having a mounting hole 32 for the drive shaft 11 at the center, a plurality (eight) of segment tips 33 brazed to the outer circumferential end of the blade substrate 31, a plurality (eight) of escape grooves 34 formed on the outer circumferential part of the blade substrate 31, and a plurality (eight) of cooling liquid flow paths 35 formed radially inside the blade substrate 31. The blade substrate 31 is formed by bonding together a thin plate-shaped (thin disk-shaped) first substrate 40 and a thin plate-shaped (thin disk-shaped) second substrate 50.

[0037] The first substrate 40 is formed with a first mounting hole 41 constituting the mounting hole 32, eight first U-shaped grooves 42 constituting the relief groove 34, and eight first flow path grooves 43 constituting the coolant flow path 35. Similarly, the second substrate 50 is formed with a second mounting hole 51 constituting the mounting hole 32, eight second U-shaped grooves 52 constituting the relief groove 34, and eight second flow path grooves 53 constituting the coolant flow path 35. The blade substrate 31 is formed by butting the back surfaces of the first substrate 40 and the second substrate 50 thus formed together and spot welding them at eight welding points 55 (see FIG. 3).

[0038] The second mounting hole 51 is formed with a larger diameter than the first mounting hole 41 (see FIG. 3). As a result, a mounting hole 32 having an annular step 32a is formed in the center of the blade substrate 31. The inlet 35a of each cooling liquid flow path 35 opens at the annular step 32a, and the outlet 35b of each cooling liquid flow path 35 opens at the groove bottom 34a of each escape groove 34. Therefore, in this cutting wheel 20, the cooling liquid supplied through the cooling liquid flow path 35 is supplied to the segment chip 33 via the escape groove 34.

[0039] [Mounting unit] Next, the mounting unit 14 for the cutting wheel 20 will be described with reference to the half cross-sectional view of Fig. 6 and the exploded view of Fig. 7. The mounting unit 14 mounts the cutting wheel 20 to the drive shaft 11 in a state in which the coolant can be supplied (removably mounted). As shown in both figures, the drive shaft 11 has a rotation prevention cut shaft portion 11a (rotation prevention shaft portion) and a male screw-shaped shaft portion 11b (male screw shaft portion) coaxially protruding from the end face of the rotation prevention cut shaft portion 11a. In contrast, the mounting unit 14 includes an inner flange 61, a lock nut 62, and a supply joint portion 63.

[0040] In this case, the inner flange 61 engages with the anti-rotation cut shaft portion 11a of the drive shaft 11 and has the function of positioning the cut-off wheel 20 coaxially with the drive shaft 11. The lock nut 62 screws onto the male threaded shaft portion 11b of the drive shaft 11 to hold the cut-off wheel 20 between itself and the inner flange 61 and has the function of supplying coolant to the coolant flow path 35 of the cut-off wheel 20. The supply joint portion 63 has the function of supplying coolant supplied from a coolant supply device (not shown) to the rotating lock nut 62.

[0041] 6, 7 and 8, the inner flange 61 is integrally formed with a shaft engaging portion 71 that engages with the anti-rotation cut shaft portion 11a of the drive shaft 11, a substrate fitting portion 72 that is connected to the shaft engaging portion 71 and positions the cutting wheel 20 (blade substrate 31) coaxially with the drive shaft 11, and a clamping contact receiving portion 73 that is connected to the shaft engaging portion 71 and comes into contact with the cutting wheel 20. Also, an insertion hole 74 is formed in the axis of the inner flange 61, through which the male threaded shaft portion 11b of the drive shaft 11 is inserted.

[0042] In this inner flange 61, the shaft engagement portion 71 is engaged with the anti-rotation cut shaft portion 11a from above so that the male threaded shaft portion 11b passes through the insertion hole 74. In this manner, the inner flange 61 is set on the drive shaft 11, and the cutting wheel 20 is seated on the clamping contact receiving portion 73 with the mounting hole 32 (first mounting hole 41) fitted into the board fitting portion 72 for the set inner flange 61.

[0043] As shown in Figures 6, 7 and 9, the lock nut 62 has a nut body 81 with a D-cut tool hook portion 81a formed on the outer periphery, a ring-shaped convex portion 82 protruding from the tip side of the nut body 81, and an annular clamping contact portion 83 formed on the base end side of the nut body 81 and clamping the cutting wheel 20 between it and the inner flange 61.

[0044] The lock nut 62 also has a coolant reservoir 84 recessed into the inside of the clamping contact portion 83 and facing the annular step portion 32a of the cutting wheel 20, a female threaded portion 85 whose tip side is connected to the coolant reservoir 84 and screws into the male threaded shaft portion 11b of the drive shaft 11, two recessed flow passage portions 86 recessed into two locations of the female threaded portion 85, and a connecting female threaded portion 87 which is coaxially connected to the tip side of the female threaded portion 85 and screws into a connecting male threaded member 92 described later.

[0045] In this case, the female thread portion 85 and the connecting female thread portion 87 are formed on the axis of the nut body 81. By screwing the lock nut 62 onto the drive shaft 11 via the female thread portion 85, the drive shaft 11, the inner flange 61, the cut-off wheel 20 and the lock nut 62 are integrated and rotate integrally.

[0046] The coolant reservoir 84 faces the annular step 32a of the cut-off wheel 20 on the outside of the threaded male threaded shank 11b, and sends coolant to the coolant flow path 35 of the cut-off wheel 20. The female threaded portion 85 has a sufficient depth relative to the length of the male threaded shank 11b. That is, the base end half of the female threaded portion 85 forms the threaded region 85a of the male threaded shank 11b, and the tip end half forms the non-threaded region 85b which serves as a coolant flow path.

[0047] Each recessed flow passage 86 is formed radially in the female thread portion 85 to have a U-shaped cross section, and extends from the coolant reservoir 84 to the tip of the female thread portion 85. The two recessed flow passages 86 are formed at 180° point symmetric positions by cutting out the threads of the female thread portion 85. That is, the connecting female thread portion 87, the non-threaded region 85b of the female thread portion 85, the two recessed flow passages 86, and the coolant reservoir 84 are in communication with each other, and coolant can be supplied to the cutting wheel 20 from the supply joint portion 63 via the lock nut 62.

[0048] As shown in FIGS. 6, 7, 10 and 11, the supply joint portion 63 includes a joint body 91 (see FIG. 10) and a connecting male screw member 92 that connects the joint body 91 to the lock nut 62 (see FIG. 11).

[0049] The connecting male screw member 92 is threadedly engaged with the connecting female screw portion 87 of the lock nut 62 while being inserted (penetrating) through the joint body 91. A first O-ring 93 is interposed between the lock nut 62 and the joint body 91, and a second O-ring 94 and a spacer ring 95 are interposed between the joint body 91 and the head portion 101 of the connecting male screw member 92.

[0050] As a result, the joint body 91 seals the coolant supplied between it and the lock nut 62, and in this state allows rotation of the lock nut 62. That is, a coolant supply device (not shown) is connected to the joint body 91 via the liquid supply tube 21, and the supply joint part 63 supplies the coolant to the rotating lock nut 62.

[0051] The connecting male screw member 92 has a head portion 101 and a shaft portion 102, and a male screw 102a is formed at the tip portion of the shaft portion 102 to screw into the connecting female screw portion 87 of the lock nut 62. A bottomed axial hole 103 which serves as a flow path for the coolant is drilled from the male screw 102a side at the axial center of the shaft portion 102. In addition, a radial hole 104 which penetrates radially and communicates with the axial hole 103 is formed at the middle portion of the shaft portion 102.

[0052] When the connecting male thread member 92 is screwed into the connecting female thread portion 87 of the lock nut 62, the space between the joint body 91 and the lock nut 62 and the space between the joint body 91 and the head 101 of the connecting male thread member 92 are sealed, and the axial hole 103 and the connecting female thread portion 87 are connected.

[0053] The joint body 91 is integrally formed with a rotation allowing portion 111 through which the connecting male screw member 92 passes, and a tube connection portion 112 to which the liquid supply tube 21 is connected. The rotation allowing portion 111 is formed with a first seal receiving hole 113 into which the above-mentioned first O-ring 93 is attached, and a second seal receiving hole 114 into which the second O-ring 94 and the spacer ring 95 are attached.

[0054] Further, the rotation allowing portion 111 is formed with a loose fitting hole 116 located between the first seal receiving hole 113 and the second seal receiving hole 114, which constitutes an annular liquid pool 115 of the coolant between the inserted connecting male screw member 92 (shaft portion 102). This allows the annular liquid pool 115 of the joint body 91 to communicate with the axial hole 103 of the connecting male screw member 92 via the radial hole 104 of the connecting male screw member 92. In other words, the coolant in the annular liquid pool 115 can always be supplied to the connecting male screw member 92 which rotates integrally with the lock nut 62.

[0055] The tube connection part 112 is formed with a tapered female thread 117 into which a coupler of the liquid supply tube 21 screws. By connecting the liquid supply tube 21 to this tapered female thread 117, it becomes possible to supply the liquid coolant from the liquid coolant supply device to the joint body 91.

[0056] The tip of a rotation-stop arm 18 extending from a cover holder 17 (described later) engages with the joint body 91 (see FIG. 1). This prevents the joint body 91, to which the liquid supply tube 21 is connected, from rotating together with the lock nut 62.

[0057] In this way, the cutting wheel 20 is attached to the drive shaft 11 of the cutting device 20 via the attachment unit 14, so that the cutting wheel 20 having the coolant flow path 35 can be detachably and properly attached. In other words, the cutting wheel 20 can be attached to the drive shaft 11 via the attachment unit 14 in a state in which the coolant can be supplied.

[0058] [Disc cover] Next, the disk cover 16 will be described with reference to Figures 12 to 14. The disk cover 16 covers the cutting wheel 20 and has a function of preventing unnecessary scattering of the waste cooling liquid, and also has a function of sucking and collecting the waste cooling liquid.

[0059] As shown in these figures, the disc cover 16 includes a cover body 121 that covers the cutting wheel 20 to form a shielded space 122, an outer cover 124 that covers the periphery of the cut-out open end 123 side of the cover body 121 and forms a suction space 125 between the cover body 121 and the outer cover 124, and a suction joint portion 126 attached to the outer cover 124. The cover body 121 also includes a bottom cover 127 that forms the cut-out open end 123, a top cover 128 that is joined to the bottom cover 127, and a cover joint portion 129 for joining the top cover 128 to the bottom cover 127 (see FIG. 14(b)).

[0060] The top cover 128 is made of transparent plastic. The bottom cover 127, the cover joint 129, the outer cover 124 and the suction joint 126 constitute a bottom unit 130, which is integrally made of rubber. The lower end of the top cover 128 and the upper end of the bottom cover 127 are formed to have the same shape so that no step is created in the shielded space 122. In addition, the cover joint 129 is formed to be located outside the lower end of the top cover 128 and to protrude from the bottom unit 130.

[0061] The top cover 128 is inserted and joined to the cover joint 129 so that its lower end abuts against the upper end of the bottom cover 127. In other words, the disc cover 16 has a structure in which the top cover 128 is detachably attached to the bottom unit 130, and the disc cover 16 and the cutting wheel 20 can be easily attached and detached to and from the device body 13.

[0062] 15 shows a modified example of the area around the cover joint 129 of the disc cover 16. In this modified example, a first locking projection 128a and a first locking hole 128b are formed at the lower end of the top cover 128, and correspondingly, a second locking hole 129a and a second locking projection 129b are formed at the cover joint 129. When the lower end of the top cover 128 is inserted into the cover joint 129, the first locking projection 128a is clickably locked into the second locking hole 129a, and the second locking projection 129b is clickably locked into the first locking hole 128b. This allows the top cover 128 to be securely attached to the bottom unit 130.

[0063] Further, a position indicator member 140 is provided at the front end of the outer cover 124 (the front end of a side wall portion 137 described later) for indicating the position of the cutting wheel 20 in the left-right direction. The position indicator member 140 is made of a stainless steel pin-shaped member, and is attached so as to protrude from the side wall portion 137 of the outer cover 124. The position indicator member 140 indicates the position of the cutting wheel 20 covered by the disc cover 16, and the operator proceeds with the cutting operation while aligning this position indicator member 140 with the cutting line (e.g., a marking line) of the workpiece S.

[0064] In addition, in the cutting device 10, it is also possible to perform the cutting operation while pulling the cutting wheel 20 toward the user. Therefore, it is preferable to provide a position indicator member 140 at the rear end of the outer cover 124. The position indicator member 140 provided at the rear end may be something like a white line drawn on the outer cover 124.

[0065] 13, the top cover 128 has a semicircular portion 131 facing the cutting wheel 20 and a joint end portion 132 connected to the semicircular portion 131, and defines a shielded space 122 inside. Shaft openings 133a, 133b facing the drive shaft 11 and the mounting unit 14 are formed on the side of the top cover 128. The shaft opening 133b on the rear side facing the drive shaft 11 is formed narrow, and the shaft opening 133a on the front side facing the mounting unit 14 is formed wide. A top fixing portion 134 to which a crank plate 173 (described later) is fixed is formed on the top of the top cover 128.

[0066] 14, the bottom unit 130 has a bottom cover 127 which is an extension of a top cover 128, a cover joint 129 extending upward on the outside of the bottom cover 127, an outer cover 124 disposed on the outside of the bottom cover 127 with a suction space 125 formed therebetween, and a suction joint 126 extending rearward from one end of the outer cover 124. The shielded space 122 which constitutes the top cover 128 and the bottom cover 127 communicates with a suction space 125 constituted by the bottom cover 127 and the outer cover 124 at the lower end of the bottom cover 127 (see FIG. 16), and the suction space 125 communicates with the internal space of the suction joint 126.

[0067] As described above, the bottom unit 130 is made of rubber, and when the top cover 128 is attached to the cover joint 129, the oval shaft openings 133a, 133b are formed on the rear and front sides of the side (see FIG. 12). The cover body 121 of the embodiment has a two-part structure of the top cover 128 and the bottom cover 127, and the two oval shaft openings 133a, 133b also have a two-part structure, one above the other. When air is sucked in under this condition, air flows into the shielded space 122 from the shaft openings 133a, 133b. When air is sucked in from the disc cover 16, the two shaft openings 133a, 133b serve as air intakes, and the waste cooling liquid is carried by the sucked air from here and discharged to the outside.

[0068] The cover joint portion 129 is formed so as to extend upward from the top wall portion 136 of the outer cover 124. The bottom cover 127 is continuous with the top wall portion 136, and is formed so as to extend downward on an extension of the top cover 128. The outer cover 124 is composed of the top wall portion 136 and a side wall portion 137, and a suction space 125 continuous with the suction joint portion 126 is formed therein.

[0069] In this case, the cut open end 123, which is the lower end of the bottom cover 127, faces the workpiece S with a small flow path gap 139 (flow path) therebetween. The air containing the waste cooling liquid increases its flow rate at the flow path gap 139 and flows into the suction space 125 (see FIG. 16). Meanwhile, the contact open end 124a, which is the lower end of the outer cover 124, is configured so that the outer half of its thickness is in airtight contact with the workpiece S. The waste cooling liquid generated in the shielded space 122 flows into the suction space 125 by passing through the flow path gap 139 between the cut open end 123 and the workpiece S, and is led from the suction space 125 to the suction joint part 126.

[0070] The flow path gap 139 does not need to be continuous in a plane, and may be discontinuous in an uneven or wavy shape. Also, instead of the flow path gap 139, a number of small holes may be formed side by side, or a combination of these may be used. However, in this embodiment, the total cross-sectional area of ​​the flow path gap 139 (flow path for suction) is configured to be sufficiently smaller than the cross-sectional area of ​​a suction port 142 of the suction joint part 126 described later. This increases the flow rate of the air flowing through the flow path gap 139, enabling efficient suction of the waste cooling liquid.

[0071] The suction joint 126 is attached to an end of the outer cover 124, and has at one end a communication port 141 communicating with the suction space 125, and at the other end a suction port 142 for air-suctioning waste cooling liquid resulting from grinding (see FIG. 14). The waste liquid tube 22 is connected to the suction port 142 via the joint 27 (see FIG. 1), and a waste cooling liquid recovery device (not shown) is connected to the downstream end of the waste liquid tube 22.

[0072] In this case, a modified cleaner-type dust collector is used as the cooling waste liquid recovery device in consideration of costs. Therefore, the cooling waste liquid recovery device has a limit to the air suction force, and if the amount of air (leak air) flowing in from the two shaft openings 133a and 133b is large, the suction space 125 does not become a sufficiently negative pressure, and the cooling waste liquid cannot be efficiently sucked by air.

[0073] 17 and 18, in this embodiment, a first inflow suppression member 143 and a second inflow suppression member 144 are provided inside the two shaft openings 133a, 133b to suppress the inflow of air from the two shaft openings 133a, 133b during air suction. The first inflow suppression member 143 and the second inflow suppression member 144 are formed of impellers made of rubber or plastic, and rotate together with the cutting wheel 20 (drive shaft 11).

[0074] The first inflow suppression member 143 and the second inflow suppression member 144 are each formed of an impeller that rotates to send the air in the cover body 121 to the outside. The first inflow suppression member 143, which is formed to be wide, is attached to the nut body 81 of the lock nut 62 in the form of a key (the first inflow suppression member 143 side is convex and the nut body 81 side is concave), and rotates together with the lock nut 62 to send the air in the cover body 121 to the outside (the lock nut 62 side). Similarly, the second inflow suppression member 144 is attached to the clamping contact receiving portion 73 of the inner flange 61 in the form of a key (the second inflow suppression member 144 side is convex and the clamping contact receiving portion 73 side is concave), and rotates together with the inner flange 61 to send the air in the cover body 121 to the outside (the device body 13 side).

[0075] In this case, the air supply from the first inflow suppression member 143 and the second inflow suppression member 144 is performed in a manner that resists the air suction of the waste cooling liquid recovery device. On the other hand, since the cover body 121 is not a sealed case, the air supply from the first inflow suppression member 143 and the second inflow suppression member 144 substantially suppresses the inflow of air from the shaft openings 133a and 133b. As a result, the suction space 125 is in a sufficiently negative pressure state, and the waste cooling liquid can be efficiently sucked with air.

[0076] 19 and 20 show modified examples of the first inflow suppression member 143 and the second inflow suppression member 144. In this case, the first inflow suppression member 143A and the second inflow suppression member 144A are formed of ring-shaped urethane foam (closed foam). The first inflow suppression member 143A and the second inflow suppression member 144A are disposed so as to be in contact with the cover body 121 from the inside.

[0077] In this case as well, the first inflow suppression member 143A is attached (fitted) to the nut body 81 of the lock nut 62, and rotates together with the lock nut 62 while in contact with the cut-off wheel 20. Similarly, the second inflow suppression member 144A is attached (fitted) to the clamping contact receiving portion 73 of the inner flange 61, and rotates together with the inner flange 61 while in contact with the cut-off wheel 20.

[0078] In this modification, the lock nut 62 is compactly formed, and the shaft openings 133a, 133b are formed as narrow as possible. The first inflow suppression member 143A and the second inflow suppression member 144A are arranged to close the shaft openings 133a, 133b while allowing a certain amount of leak air. If the amount of leak air is extremely small compared to the suction force of the cooling waste liquid recovery device, the cover body 121 is strongly attracted to the cutting object S and becomes difficult to move. In such a case, it is preferable to deal with this by forming the first inflow suppression member 143A and the second inflow suppression member 144A thin, or by providing a notch in a part of the lower end of the outer cover 124.

[0079] In this way, the first inflow suppression member 143A and the second inflow suppression member 144A facing the shaft openings 133a, 133b suppress the inflow of air from the shaft openings 133a, 133b as much as possible. This creates a sufficiently negative pressure in the suction space 125, allowing the waste cooling liquid to be efficiently sucked by air.

[0080] 21 and 22 show an unevenness attachment 145 that is detachably attached to the lower end of the outer cover 124. When the workpiece S has unevenness (unevenness), even if the contact open end 124a of the outer cover 124, which is formed flat, is tried to contact it, a gap may be generated, causing air leakage and preventing good suction of the waste cooling liquid. Therefore, an unevenness attachment 145 that absorbs the unevenness of the workpiece S is provided.

[0081] The uneven attachment 145 is made of sponge (independently foamed urethane) and has an external appearance formed in a rectangular parallelepiped shape that is slightly larger than the outer cover 124. On the inside of the uneven attachment 145, there are formed a joint step portion 146 into which the side wall portion 137 of the outer cover 124 fits, and a through opening portion 147 that is continuous with the joint step portion 146 (see FIG. 22).

[0082] When the uneven attachment 145 is attached to the disk cover 16, the lower part of the uneven attachment 145 deforms to absorb the unevenness of the workpiece S (see FIG. 22). That is, the contact open end 124a of the outer cover 124 comes into close contact with the uneven workpiece S through the uneven attachment 145. As a result, the through opening 147, which is the internal space of the uneven attachment 145, faces the workpiece S, and the shielding space 122 and the suction space 125 face this through opening 147. In this case as well, the cooling waste liquid flows into the suction space 125 through the flow path gap 139 between the cut open end 123 and the workpiece S, and is led from the suction space 125 to the suction joint part 126.

[0083] [Cover holder] 23 to 25, the cover holder 17 that holds the disc cover 16 on the device body 13 will be described. The cover holder 17 has a body mounting part 151 that is fixed to the device body 13, a holder guide part 152 that is connected to the body mounting part 151 and holds the disc cover 16 slidably in the cutting direction of the cutting wheel 20, and a spring mechanism 153 that biases the disc cover 16 toward the cutting side (see FIG. 1).

[0084] The device body 13 is provided with a fixing nut 155 for attachment on the upper surface adjacent to the disk mounting base 24, and the body mounting part 151 is fixed to this fixing nut 155 with a screw (see FIG. 2). The body mounting part 151 has a right-angled triangular mounting plate 156 that slopes downward toward the front, a mechanism base 157 that is fixed onto the mounting plate 156 and for mounting the spring mechanism 153, and a clearance hole 158 for screwing the fixing nut 155.

[0085] The body mounting part 151, which is screwed to the fixing nut 155 via the clearance hole 158, has a mounting plate 156 that is slightly inclined downward toward the front and has its bottom side parallel to the disc mounting base 24, i.e., parallel to the disc cover 16. The mounting plate 156 and a guide plate 162 of the holder guide part 152, which will be described later, are formed by bending a single sheet of plate material, and are attached to the device body 13 via the mounting plate 156 so that the holder guide part 152 (guide plate 162) covers the disc mounting base 24.

[0086] The holder guide section 152 has a ring-shaped sliding guide section 161, a guide section plate 162 to which the sliding guide section 161 is attached, and two arm attachment holes 163 formed in the lower part on the tip side of the guide section plate 162. The sliding guide section 161 is made up of a short cylinder section 165 and a retaining disk 166 fixed to one end face of the short cylinder section 165, and is fixed to a semicircular cutout section 162a of the guide section plate 162 at the other end of the short cylinder section 165.

[0087] Although not shown in the drawings, the drive shaft 11 of the disk mounting base 24 faces the center of the sliding guide portion 161 (short cylinder portion 165), and the shaft opening 133b of the disk cover 16 (cover body 121) slidably engages with the short cylinder portion 165 (see FIG. 25). In other words, the shaft opening 133b constitutes a sliding portion that is guided by the sliding guide portion 161. As a result, even when the cutting wheel 20 cuts into the workpiece S, the contact open end 124a of the outer cover 124 is always in close contact with the surface of the workpiece S, and the suction and recovery of the waste cooling liquid is smoothly performed.

[0088] On the other hand, the anti-rotation arm 18 is fixed by screws in the two arm attachment holes 163 (see FIG. 2). The anti-rotation arm 18 is integrally formed of a bifurcated head portion 18a that engages with the joint body 91 of the above-mentioned mounting unit 14, and a curved arm portion 18b that holds the bifurcated head portion 18a and is screwed to the arm attachment hole 163 at its base end. The curved arm portion 18b extends from the position of the holder guide portion 152 to the position of the mounting unit 14, bypassing the disc cover 16. The bifurcated head portion 18a provided at the tip of the curved arm portion 18b engages with the joint body 91 (see FIG. 1), preventing it from rotating together with the lock nut 62 of the joint body 91 to which the liquid supply tube 21 is connected.

[0089] The spring mechanism 153 returns the disc cover 16, which slides via the sliding guide portion 161, to its original position (home position). That is, the cutting wheel 20 attached to the drive shaft 11 of the cutting device 10 cuts into the workpiece S by hand operation of the device body 13, and at that time, the disc cover 16 must always be in elastic contact with the workpiece S. In other words, when the cutting wheel 20 cuts into the workpiece S, the disc cover 16, which moves upward relatively, must always be biased toward the home position.

[0090] As shown in Figures 23 to 25, the spring mechanism 153 has a rod-shaped guide 171 erected on the mechanism base 157 of the body mounting portion 151, a coil spring 172 (compression spring) wound around the rod-shaped guide 171, and a crank plate 173 whose lower end is slidably engaged with the rod-shaped guide 171 and whose upper end is fixed to the top of the disc cover 16.

[0091] The crank plate 173 is formed by bending a strip of material onto a crank, and is integrally formed with a lower end flat portion 175 that engages with the rod-shaped guide 171, an upper end flat portion 176 that is fixed to the disc cover 16, and a connecting flat portion 177 that connects the lower end flat portion 175 and the upper end flat portion 176.

[0092] A guide hole 175a corresponding to the diameter of the rod-shaped guide 171 is formed in the lower end flat plate portion 175, and the crank plate 173 is engaged with the rod-shaped guide 171 via this guide hole 175a so as to be slidable in the up and down direction. In addition, the upper end flat plate portion 176 is fixed to the top fixing portion 134 of the disc cover 16 (top cover 128) by screws.

[0093] The coil spring 172, wound around the rod-shaped guide 171, is interposed between a stopper disk 178 provided at the upper end of the rod-shaped guide 171 and a lower end flat plate portion 175 of the crank plate 173. When the disc cover 16 moves upward, the crank plate 173 also moves upward, guided by the rod-shaped guide 171. When the crank plate 173 moves upward, the coil spring 172 is compressed between the stopper disk 178 and the lower end flat plate portion 175. As a result, a biasing force is always acting on the upward moving disc cover 16, tending to move it downward toward the home position.

[0094] 26 shows a modified example of the area around the cover holder 17. In this modified example, the position of the disc cover 16 is restricted by a sliding guide portion 161, a guide portion plate 162, a mechanism base 157A, and a crank plate 173A, but is allowed to move up and down within a predetermined dimension and tilt (rotate) at a predetermined angle.

[0095] In this case, the mechanism base 157A is formed in a "U" shape so as to sandwich the crank plate 173A from the front and rear, unlike the above-mentioned mechanism base 157A. The height of the mechanism base 157A is slightly lower than the crank plate 173A, and the end face on the disc cover 16 side is disposed flush with the guide plate 162 (see FIGS. 26(b) and (c)).

[0096] The crank plate 173A is narrower than the above-mentioned one, and has a downward flat portion 179 formed at the end of the upper flat portion 176 (see FIG. 26(b)). In this case, the disc cover 16 is not fixed to the crank plate 173A (upper flat portion 176) by screws, and is in a state where its position is restricted by the connecting flat portion 177, the upper flat portion 176, and the downward flat portion 179.

[0097] This not only allows the disk cover 16 to move up and down in accordance with the cutting operation, but also allows it to tilt about the sliding guide portion 161. Therefore, the waste cooling liquid can be appropriately collected during the cutting operation without impairing the workability of the cutting operation.

[0098] In this modified example in which the disc cover 16 is allowed to tilt, the anti-rotation arm 18 is fixed to the guide plate 162 with the device body 13 tilted at an angle of about 10°. This structure prevents the anti-rotation arm 18 from interfering with the disc cover 16 (bottom unit 130) when the disc cover 16 tilts (relative tilt). [Explanation of symbols]

[0099] 10...cutting device, 11...drive shaft, 11a...rotation stop cutting shaft portion, 11b...male threaded shaft portion, 12...motor, 13...device body, 14...mounting unit, 16...disc cover, 17...cover holder, 20...cutting wheel, 31...blade substrate, 32...mounting hole, 33...segment tip, 34...relief groove, 35...coolant flow path, 61...inner flange, 62...lock nut, 63...coolant joint member, 81...nut body, 85...female threaded portion, 86...recessed inlet flow path portion, 87...connecting female thread portion, 91...joint body, 92...connecting male thread member, 111...rotation allowance portion, 115...annular liquid reservoir, 121...cover body, 122...shielding space, 123...open end of cut, 1 24...outer cover, 124a...contact open end, 125...suction space, 126...suction joint portion, 127...bottom cover, 128...top cover, 129...cover joint portion, 130...bottom unit, 133a, 133b...shaft opening, 139...flow path gap, 140...position index member, 141...communication port, 142...suction port, 143, 143A...first inflow suppression member, 144, 144A...second inflow suppression member, 145...uneven attachment, 146...joint step portion, 147...through opening, 151...body mounting portion, 152...holder guide portion, 153...spring mechanism, 161...sliding guide portion, 172...coil spring, 173...crank plate, S...cutting object,

Claims

1. A disk cover is provided in a cutting device that cuts an object to be cut while supplying a coolant to a cutting wheel attached to a drive shaft, the disk cover covering the cutting wheel with the cutting side open, a cover body having an open end on the cut-off side and an opening for the drive shaft, the cover body covering the cutting wheel and constituting a shielded space; an outer cover having a contact open end on the cut-out side, covering the periphery of the cut-out open end side of the cover body and forming a suction space between the cover body and the outer cover; a suction joint portion attached to the outer cover, the suction joint portion having a communication port at one end thereof communicating with the suction space and a suction port at the other end thereof for air-suctioning waste cooling liquid resulting from grinding, A disk cover, characterized in that the contact open end comes into contact with the object to be cut, and the cut open end forms a flow path for suction between the object to be cut and the cut open end.

2. the cover body includes a bottom cover portion in which the cut-out open end is formed, a top cover portion joined to the bottom cover portion and formed such that the shaft opening is divided between the top cover portion and the bottom cover portion, and a cover joining portion for joining the top cover portion to the bottom cover portion, 2. The disk cover according to claim 1, wherein the bottom cover portion, the cover joint portion and the outer cover are integrally formed.

3. The top cover is made of plastic.

3. The disk cover according to claim 2, wherein the bottom cover portion, the cover joint portion and the outer cover are integrally formed of rubber.

4. 4. The disk cover according to claim 3, wherein the top cover portion is plug-joined to the cover joint portion.

5. 4. The disk cover according to claim 3, wherein the outer cover is provided with a position index member for indexing the left-right position of the cutting wheel.

6. 2. The disk cover according to claim 1, wherein a total cross-sectional area of ​​the flow paths for suction is smaller than a cross-sectional area of ​​the suction port.

7. The shaft opening is formed in two on both sides of the cutting wheel in the cover body, a first inflow suppression member and a second inflow suppression member that suppress an amount of air flowing in from the two shaft openings during air suction of the waste cooling liquid; 2. The disk cover according to claim 1, wherein the first inflow suppression member and the second inflow suppression member face the two shaft openings from the inside of the cover body, respectively, and rotate together with the drive shaft in this state.

8. Further provided is an unevenness attachment that absorbs unevenness of the object to be cut, 2. The disk cover according to claim 1, wherein the uneven attachment defines an internal space communicating with the shielding space and the suction space, and is detachably attached to the outer cover.

9. A cutting device that cuts an object to be cut while supplying a cooling liquid to a cutting wheel attached to a drive shaft, a motor having the drive shaft; a device body having the motor built-in with the drive shaft exposed; a mounting unit for mounting the cutting wheel on the drive shaft and having a supply port for supplying a coolant to the cutting wheel; A cutting device comprising: the disc cover according to claim 1.

10. a cover holder for holding the disc cover on the device body, The cover holder includes: a body attachment portion fixed to the device body; a holder guide portion connected to the body mounting portion and configured to hold the disk cover slidably in a cutting direction of the cutting wheel; 10. The cutting device according to claim 9, further comprising a spring mechanism for biasing the disk cover toward the cut-out side.

11. the holder guide portion further allows the disc cover to rotate, 11. The cutting device according to claim 10, wherein the spring mechanism includes a crank plate that engages with the disc cover so as to press the disc cover downward, and a coil spring that urges the disc cover downward via the crank plate.

12. The holder guide portion is formed with a circular sliding guide portion on which the drive shaft is coaxially disposed, The cover body is formed with an oval shaft opening, 11. The cutting device according to claim 10, wherein the disk cover is slidably engaged with the sliding guide portion through the shaft opening.

13. The drive shaft includes a rotation-preventing shaft portion and a male-threaded shaft portion coaxially protruding from an end face of the rotation-preventing shaft portion, The mounting unit includes: an inner flange that engages with the rotation-stopping shaft portion and receives the cutting wheel; a lock nut that is screwed into the male threaded shaft portion and that holds the cutting wheel between the lock nut and the inner flange; a supply joint portion that supplies a coolant to the cutting wheel via the lock nut, the lock nut having an internal passage for supplying a coolant to the cut-off wheel; The cutting device according to claim 9, characterized in that the supply joint portion has a connecting shaft portion having an axial flow passage communicating with the internal flow passage, and a rotation-permitting portion having an annular liquid reservoir surrounding the connecting shaft portion and communicating with the axial flow passage from a radial direction, and the supply port communicating with the annular liquid reservoir.

Images