CN102601712A - Dust collection adapter and power tool including dust collection adapter - Google Patents

Abstract

For the electric tool main body, there is provided a main body shaft that rotationally drives the tip tool, and a dust collection adapter for collecting dust generated when a material to be ground is processed by the tip tool is held on the electric tool main body. The dust collection adapter includes: a dust collection fan rotationally driven by the main body shaft, and a radially outer dust collection cover for accommodating the dust collection fan and covering the tip tool. The dust collection fan includes: a fan main body provided with a plurality of blade parts and a threaded shaft part provided at a central part of the fan main body. For the threaded shaft portion, there are provided an internal threaded portion threadedly coupled to the main body shaft and an external threaded portion threadedly coupled to the fastening threaded member for fixing the tip tool.

Description

Dust extraction adapters and power tools including dust extraction adapters

Cross References to Related Applications

This application claims No. 2011-073801 filed March 30, 2011, No. 2011-008439 filed Jan. 19, 2011, No. 2011-077341 filed March 31, 2011, Jan. 20, 2011 Priority claims to Japanese Patent Applications No. 2011-009386 filed on September 22, 2011 and No. 2011-207278 filed on September 22, 2011, the contents of which are incorporated herein by reference. the

technical field

The present invention relates to an electric tool, such as a disc grinder, which grinds a material to be ground through an end tool, and also relates to a dust collection adapter held to the electric tool to collect dust generated during the machining. the

Background technique

A disc grinder or the like, which is an electric tool, rotationally drives an end tool such as a rotary grindstone by a power source to process the surface of a material to be processed. In order to rotationally drive an end tool by an electric motor or a fan to perform grinding processing on the surface of a material to be processed, a disc grinder is used. As the end tool, there are disc grindstones, diamond cutters, cup grindstones, wire brushes, etc., from which an arbitrary end tool is selected based on the type of material to be ground. For example, for grinding the surface of a material to be processed such as concrete or stone, a diamond cutter is selected as an end tool, and the surface is ground by an electric tool. A power tool that grinds the surface of the material to be processed by means of an end tool is also called a "disk grinder" or "polisher". the

An electric tool such as a disc grinder or a disc grinder, which performs grinding processing by an end tool, has a dust collection type including a dust collection adapter by which dust generated during processing is not scattered outside. For example, Patent Document 1 (Japanese Patent Application Publication No. 2009-138203) and Patent Document 2 (Japanese Utility Model Patent Application Publication No. S55-103143) describe a disc grinder configured as Keep the dust brush to the opening part of the dust cover. Inside the dust collecting cover described in Patent Document 3 (Japanese Patent Application Laid-Open No. 2009-23005), a guide member for guiding the dust toward the discharge duct is provided. Inside the dust collecting cover of the electric tool described in Patent Document 1, a dust collecting fan for sucking dust and supplying the dust to a discharge duct is provided. The dust collection adapter is formed by a dust collection fan and a dust collection cover, the dust collection fan is held on the rotating shaft for driving the end tool, and the dust collection cover is used to cover the dust collection fan. the

Contents of the invention

An electric power tool such as a disc grinder or a disc grinder has a dust collecting type including a dust collecting cover held thereon and a general simple type not including a dust collecting cover. Optionally, the simple electric tool has a structure in which a dust collection adapter can be connected to the main body of the electric tool, and the dust collection adapter is obtained by assembling a dust collection fan and a dustproof cover installed in the dust collection fan. In the simple type, the shaft for driving an end tool such as a grindstone has such a length that the end tool is directly attached to the shaft. Therefore, when the dust collecting fan and the dust collecting cover are connected to a simple electric tool, the length of the rotating shaft is insufficient, which will cause difficulty in connecting the end tool. the

In order to make the simple electric tool a dust-proof electric tool without disassembling the shaft previously provided on the simple electric tool, that is, without disassembling the main shaft, it is necessary to couple a threaded shaft member as an extension shaft to the end of the main shaft. In order to couple the extension shaft to the main body shaft, an internal thread portion screw-coupled to the external thread portion of the main body shaft is provided at a bottom end portion of the extension shaft. And, in order to connect the tip tool to the tip portion of the extension shaft, an external thread portion screw-coupled with a lock nut for fastening the tip tool is provided to the tip of the extension shaft. the

On the other hand, when the end tool is connected to and separated from the main body shaft for exchanging the end tool, that is, when combined with and separated from the main body shaft, the lock button provided on the electric tool body is operated to lock the the main body shaft so as not to turn the main body shaft. Therefore, when the end tool is replaced, while the worker operates the lock button with one hand to fix the main body shaft, the worker can rotationally operate the lock nut with the other hand to fasten the end tool to the main body shaft. the

However, in order to replace the end tool that has been connected to the extension shaft, if one tries to loosen the lock nut that has been fastened to the end tool while preventing the rotation of the main body shaft by the lock button, the lock nut does not rotate relative to the extension shaft, and The lock nut rotates together with the extension shaft, therefore, the threaded coupling portion between the extension shaft and the main body shaft can be loosened, which will separate them from each other. the

If the extension shaft is loosened and separated from the main body shaft, there occurs a state in which the extension shaft and the end tool are fixed to each other, and therefore, another work of separating the end tool from the extension shaft is required, so that workability at the time of tool replacement is poor . the

A preferred object of the present invention is to provide a dust collection adapter and a power tool including the dust collection adapter to which end tools such as grinding stone wheels can be attached even by utilizing a structure that provides a dust collection function to a general power tool body. on the adapter. the

Another preferred object of the present invention is to provide a dust collection adapter and an electric tool including the dust collection adapter, which can improve workability for exchanging a tip tool such as a grinding stone wheel with respect to the electric tool main body. the

An aspect of the present invention is that the dust collection adapter is connected to the power tool body and collects dust generated when a material to be ground is machined by an end tool rotationally driven by a body shaft of the power tool body. The dust collection adapter is arranged such that the dust collection adapter includes: a dust collection fan rotatably driven by the main body shaft, and a dust collection cover held to the power tool body to accommodate the dust collection fan therein, the dust collection cover covering the end Radially outside of the tool, the dust collection fan includes: a fan main body having a plurality of blades, and a threaded shaft portion provided to a radial center portion of the fan main body, and formed in the threaded shaft portion to be screw-coupled to the main body rotating shaft An internally threaded portion of the externally threaded portion threadably coupled to the externally threaded portion for fixing the tip tool is provided at the end of the threaded shaft portion. the

Another aspect of the present invention is that the power tool grinds the material to be ground through the end tool. The electric tool is provided so that the electric tool includes: an electric tool main body provided with a main body shaft for rotationally driving an end tool, a dust collection fan rotationally driven by the main body shaft, and a dust collecting cover held to the electric tool main body to accommodate a dust collection fan therein, the dust collection cover covers the radially outer portion of the end tool, the dust collection fan includes: a fan main body having a plurality of blades, and a threaded shaft portion provided to a radial center portion of the fan main body On the threaded shaft part, an internal threaded part threadedly coupled to the external threaded part of the main body rotating shaft is formed, and an external threaded part threadedly coupled to the fastening member for fixing the end tool is provided in the threaded shaft part, when processing The dust generated when the material to be ground is sucked into the dust cover. the

The threaded shaft part connected with the main body rotating shaft arranged on the electric tool body is arranged on the fan body of the dust collecting fan, and the external threaded part threadedly coupled with the fastening member for fixing the end tool is arranged on the threaded shaft part. Therefore, when a dust collecting function is provided to a general-purpose electric tool body not provided with a dust collecting cover, the dust collecting fan and the dust collecting cover can be kept to the main body rotating shaft without replacing the main body rotating shaft. the

When turning the fastening member screw-coupled with the external thread portion of the threaded shaft portion to fasten the end tool, the connecting/separating jig engages with the rotation restricting portion of the threaded shaft portion, and the fastening member engages with another connecting/separating jig , so that the fastening member can be easily rotated relative to the threaded shaft portion. In this way, when the fastening member is connected/detached from the threaded shaft portion, that is, when the tip tool is replaced, the fastening member can be easily separated from the threaded shaft portion, and therefore, the reliability when replacing the tip tool can be improved. Usability. the

Description of drawings

1 is a partially cutaway front view showing a disc grinder used as an electric tool in a state where a dust collection adapter is held;

Figure 2 is an enlarged sectional view of the main part of Figure 1;

Fig. 3 is an enlarged sectional view showing the disc grinder in a state where the dust collection adapter is removed;

Figure 4 is a sectional view showing the operation of removing the dust collection adapter from the disc grinder;

Fig. 5 is the bottom view of Fig. 4;

Figure 6 is an exploded view showing the dust collection adapter separated from the disc grinder;

FIG. 7A is an enlarged front view showing the end portion of the main body shaft;

Figure 7B is an enlarged cross-sectional view showing an extended shaft portion;

Figure 8 A is a front view showing a modified embodiment of an extended shaft portion;

Figure 8B is a right side view of Figure 8A;

Figure 9A is a front view showing another modified embodiment of the extended shaft portion;

Figure 9B is a right side view of Figure 9A;

Figure 10A is a front view showing yet another modified embodiment of the extended shaft portion;

Fig. 10B is the right side view of Fig. 10A;

Figure 11A is a front view showing yet another modified embodiment of the extended shaft portion;

Fig. 11B is the right side view of Fig. 11A;

Fig. 12A is a front view showing yet another modified embodiment of the extended shaft portion;

Fig. 12B is the right side view of Fig. 12A;

Fig. 13 A is a front view showing yet another modified embodiment of the extended shaft portion;

Fig. 13B is the right side view of Fig. 13A;

Fig. 14 is a sectional view showing a disc grinder in a state of holding a dust collection adapter as a modified embodiment;

Figure 15 is an exploded view showing the dust collection adapter separated from the disc grinder shown in Figure 14;

Figure 16 is a sectional view showing a dust collection adapter with a mesh member;

Figure 17 is a bottom view showing the disc grinder holding the dust collection adapter shown in Figure 16;

Figure 18 is a perspective view of the disc grinder shown in Figure 17;

Fig. 19 is a cross-sectional view showing the inclination angle of the leaf spring and the guide member shown in Fig. 16 along the circumferential direction;

Figure 20 is an enlarged sectional view obtained along line 20-20 in Figure 17;

21 is a bottom view showing a disc grinder holding a dust collection adapter as another modified embodiment;

Fig. 22 is a bottom view showing a disc grinder holding a dust collection adapter as a further modified embodiment; Fig. 23 is a part showing a disc grinder holding a dust collection adapter as a further modified embodiment section view;

Figure 24 is a bottom view of Figure 23;

Fig. 25 is an enlarged side view showing an engagement groove formed in a retainer;

Figure 26 is an exploded perspective view showing a retainer and a skirt member connected thereto;

Figure 27 is an enlarged cross-sectional view showing a retainer and a skirt member connected thereto;

28A is an enlarged front view showing a part of the skirt member and the dust collecting cover in a state where the skirt member hits a foreign object;

28B is a side sectional view showing a skirt member in a state in which the skirt member hits a foreign object;

Fig. 29 A is a bottom view showing a part of a skirt member as a modified embodiment;

Figure 29B is a sectional view obtained along line 29B-29B among Figure 29A;

30A is a bottom view showing a part of a skirt member as another modified embodiment;

Figure 30B is a cross-sectional view obtained along line 30B-30B among Figure 30A;

Fig. 31 is an enlarged front view showing a part of a skirt member and a dust collecting cover as a modified embodiment;

Fig. 32 is a partially cutaway front view showing a disc grinder holding a dust collection adapter as still another modified example. the

Figure 33 is a bottom view of Figure 32;

Figure 34 is an enlarged cross-sectional view showing a part of the skirt member shown in Figure 33 and a retainer connected with the skirt member;

35 is a bottom view showing a disc grinder holding a dust collection adapter as yet another modified embodiment;

Fig. 36 is a sectional view showing a part of a skirt member as yet another modified embodiment; and

Fig. 37 is a bottom view showing a disc grinder holding a dust collection adapter as still another modified example. the

Detailed ways

The power tool shown in the drawings is a portable, hand-held disc grinder 10 . The disc grinder 10 is used, for example, for grinding concrete materials, stone materials or other materials to be ground, and the disc grinder 10 is also referred to as a "disk grinder". In each figure, the same reference symbols designate the same components. the

As shown in FIGS. 1 and 2, a disc grinder 10 includes a cylindrical motor housing 11a and a gearbox 11b connected to an end portion thereof, and a motor 12 is housed in the motor housing 11a as a power source, as shown in FIG. The motor 12 is connected to a commercial power supply (not shown) via a power supply line 13 drawn out from the rear end portion of the motor housing 11a, and the motor 12 is driven by power supplied from the commercial power supply. A bevel gear 15 is connected to the rotating shaft 14 of the motor 12 , and a bevel gear 16 meshes with the bevel gear 15 . The bevel gear 16 is connected to a main body rotating shaft 17 arranged at right angles to the rotating shaft 14 . In this way, the torque of the motor 12 is transmitted to the main body shaft 17 via the bevel gears 15 and 16 to rotate the main body shaft about the rotation center axis. The main body shaft 17 is rotatably supported by a bearing 18 connected to the gearbox lib. The support 18 is connected to the gearbox lib by means of a cylindrical member 19 fixed to the gearbox lib. The cylindrical member 19 is provided coaxially with the main body rotation shaft 17 , and the cylindrical member 19 is provided radially outside the main body rotation shaft 17 . the

In the disc grinder 10 , an electric tool main body 10 a includes: a motor housing 11 a , a gearbox 11 b , and the above-mentioned members embedded inside the motor housing 11 a and the gearbox 11 b. The dust collection adapter 20 is detachably provided on the power tool main body 10a. When the dust collection adapter 20 is held on the power tool main body 10a, the type of the disc grinder 10 is the dust collection type as shown in FIG. 2 . On the other hand, when the dust collection adapter 20 is separated from the power tool main body 10a and the grinding stone wheel 23 as an end tool connected to the main body shaft 17, it becomes a simple disc grinder 10 as shown in FIG. 3 . As shown in FIGS. 2 and 3 , an externally threaded portion 21 is provided at an end portion of the main body shaft 17 . The large radial flange portion 22 is provided at a position closer to the bottom end portion of the main body shaft 17 than the externally threaded portion 21 , and the flange portion 22 strikes onto the support 18 . the

As shown in FIG. 3 , when the disc grinder 10 is a simple type, a cup-shaped grindstone wheel 23 serving as an end tool is directly connected to an external thread portion 21 at the end portion of the main body shaft 17 . The grindstone wheel 23 includes a cup-shaped base 24, and a plurality of diamond grindstones 25 are fixed to the front surface of the outer peripheral portion of the base 24 by means such as bonding. A bushing 26 is connected to a radially central portion of the base 24 . As shown in FIG. 2, the bushing 26 includes: a cylindrical portion 26a inserted into the through hole 24a of the base 24, and an annular end plate portion 26b provided at the end of the cylindrical portion 26a, and a vibration-proof rubber sheet 27 is sandwiched between Between the end plate portion 26b and the base 24 . the

The grindstone wheel 23 is connected to the main body shaft 17 through a lock nut 28 serving as a fastening member screw-coupled to the externally threaded portion 21 of the main body shaft 17 . An internally threaded portion 28 a screw-coupled to the externally threaded portion 21 is provided on the lock nut 28 . When the grindstone wheel 23 is attached to the main body shaft 17 , the cylindrical portion 26 a is inserted into the externally threaded portion 21 so that the end plate portion 26 b of the bush 26 strikes against the flange portion 22 . Next, the externally threaded portion 21 and the cylindrical portion 26a are inserted into the through hole 24a to form a state in which the base 24 is in contact with the end plate portion 26b via the anti-vibration rubber sheet 27, and the lock nut 28 is connected to the externally threaded portion 21 for For fastening and fixing. In order not to rotate the main body shaft 17 when the lock nut 28 is tightened, a lock button 29 is provided on the gearbox 11b. the

A locking pin (not shown) capable of reciprocating movement in a direction parallel to the main body rotating shaft 17 is provided on the locking button 29 . In FIG. 3, by pressing the locking button 29 to the position shown by the two-dashed line 29a, the locking pin engages with a recessed portion (not shown) formed in the bevel gear 16 to fix the bevel gear 16, Thus, the rotation of the main body rotating shaft 17 is restricted. In this way, the lock nut 28 can be easily screw-coupled to the externally threaded portion 21 by turning the lock nut 28 in a state where rotation of the main body rotation shaft 17 is restricted. In addition, when the lock nut 28 is loosened to separate from the externally threaded portion 21, the main body shaft 17 is locked by pressing the lock button 29, thereby restricting rotation. the

As shown in Figure 2, the dust collection adapter 20 includes: a dust collection fan 31 driven by the motor 12 together with the grindstone wheel 23, and a dust collection fan 31 for accommodating the dust collection fan 31 therein and covering the radially outer portion of the grindstone wheel 23 The dust cover 32. The dust collection fan 31 includes a disk portion 31a and a plurality of blade portions 31b provided on the front surface side of the disk portion 31a, so the fan main body is formed of the disk portion 31a and the blade portions 31b. The dust collecting fan 31 and the grindstone wheel 23 rotate around the central axis of rotation of the main body rotating shaft 17 . the

The dust collecting cover 32 includes an end wall portion 33 , a cylindrical peripheral wall portion 34 , and a partition wall 35 opposing the end wall portion 33 via the outer peripheral portion of the dust collecting fan 31 . The end wall portion 33 and the peripheral wall portion 34 are fixed to each other by a fixing member (not shown) such as a screw. An annular partition wall 35 protruding radially inward is integrally provided with the peripheral wall portion 34 , and a suction port 35 a is formed in the partition wall 35 . On the front surface side of the peripheral wall portion 34 , a cylindrical tool cover 36 is provided integrally with the peripheral wall portion 34 . The inner diameter of the tool cover 36 is larger than the outer diameter of the grindstone wheel 23 to cover the radially outer portion of the grindstone wheel 23 . the

At a radial center portion of the end wall portion 33, a cylindrical holding portion 33a mounted to the cylindrical member 19 of the electric tool main body 10a is provided. The dust collecting cover 32 is detachably held to the cylindrical member 19 at the holding portion 33a. When the holding portion 33 a is mounted to the periphery of the cylindrical member 19 , the dust collecting cover 32 and the tool cover 36 are fixed to the cylindrical member 19 . A fan accommodating chamber 37 is formed between the end wall portion 33 and the partition wall 35 such that the dust collection fan 31 is embedded inside the fan accommodating chamber 37 . When the dust collection fan 31 rotates, air flows into the fan housing chamber 37 from the outside through the suction port 35a. The swirl flow path 38 formed between the peripheral wall portion 34 and the outer periphery of the dust collecting fan 31 has a cross-sectional area gradually increasing toward the downstream side in the circumferential direction. As shown in FIG. 1 , a discharge duct 39 is provided on the dust collecting cover 32 to communicate with the most downstream portion of the scroll flow path 38 . the

The dust collecting cover 32 is configured by combining a first housing half 32a and a second housing half 32b, each of which is made of a resin material such as amide fiber. In the first casing half 32a, a part of the end wall portion 33 and the peripheral wall portion 34 and a part of the discharge duct 39 are combined with each other. In the second housing half 32b, the remaining portion of the peripheral wall portion 34, the remaining portion of the discharge duct 39, the partition wall 35, and the tool cover 36 are combined with each other. the

As shown in FIG. 1, the hose 39a is connected to the discharge pipe 39, and the discharge pipe 39 is connected to a dust bag (not shown) through the hose 39a. Therefore, by the rotation of the dust collection fan 31, the dust generated by the grindstone wheel 23 during the polishing process is sucked into the fan accommodation chamber 37 inside the dust collection cover 32, and then the dust is guided into the dust collection bag through the hose 39a. . In this way, dust generated during the grinding process is removed by the dust bag without being scattered around the disc grinder 10 . the

Inside the tool cover 36 , a skirt member 40 serving as a sealing member is movably provided in the axial direction of the main body rotation shaft 17 . The skirt member 40 is connected to an annular retainer 41, and a plurality of compression coil springs 42 serving as spring members are held between the retainer 41 and the partition wall 35, so that in the protruding direction from the end surface of the tool cover 36, by The compression coil spring 42 applies spring force to the skirt member 40 . When the surface of concrete or the like is polished by the grindstone wheel 23, the skirt member 40 serving as a sealing member covers the radially outer portion of the grindstone wheel 23, so that dust can be completely prevented from being blown to the outside. the

An extended shaft portion 51 serving as a threaded shaft portion is detachably attached to the bush portion 31 c of the dust collecting fan 31 . The bottom end portion 52 of the extension shaft portion 51 is inserted into the connection hole 31 d formed in the bush portion 31 c of the dust collecting fan 31 . Two planes are formed on the inner peripheral surface of the connection hole 31d so as to be shifted in phase by 180° from each other in the circumferential direction. On the other hand, as shown in FIG. 8, two planes 53 are formed on the outer peripheral surface of the bottom end portion 52 of the extension shaft portion 51 to correspond to the cross-sectional shape of the connection hole 31d and to be offset from each other by 180° in the circumferential direction. phase, thus forming a width-across-flat structure of the bottom portion 52 . As shown in FIGS. 2 and 7B , an internally threaded portion 54 , which is a threaded hole to be threadably coupled to the externally threaded portion 21 of the main body shaft 17 , is formed in the bottom end portion 52 . Through the flat surface 53 and the connecting hole 31d, the extension shaft portion 51 and the dust collecting fan 31 are positioned in the circumferential direction, and furthermore, they are arranged so as to be movable in the axial direction. In this way, when the dust collection adapter 20 is connected to the disc grinder 10, only by matching the position of the extension shaft portion 51 and the position of the connection hole 31d of the dust collection fan 31 with each other and inserting them, the rotation in the circumferential direction is realized. Positioning, so the driving force of the disc grinder 10 can be transmitted to the dust collection fan. the

An external thread portion 55 threadedly coupled to the internal thread portion 28 a of the lock nut 28 is formed on the tip end portion of the extended shaft portion 51 . The external thread portion 21 of the main body shaft 17 and the external thread portion 55 of the extension shaft portion 51 have the same outer diameter and pitch as each other, so as shown in FIG. , In addition, as shown in FIG. 2 , the grinding stone wheel 23 may be connected to the externally threaded portion 55 of the extension shaft portion 51 . The grinding stone wheel 23 is secured by a lock nut 28 threadedly coupled to the externally threaded portions 21 and 55 . As shown in FIG. 2, when the grindstone wheel 23 is connected to the main body shaft 17 via the extended shaft portion 51, and furthermore when the dust collection adapter 20 is connected to the power tool main body 10a, the type of the disc grinder 10 is a dust collection type. . On the other hand, as shown in FIG. 3, when the grindstone wheel 23 is attached to the main body shaft 17, the type of the disc grinder 10 is a simple type. the

Each of the externally threaded portions 21 and 55 is a right-handed thread and has the same helical direction as each other. Therefore, when the grinding stone wheel 23 is connected to the main body shaft 17 as shown in FIG. 3 , the lock nut 28 is screw-coupled to the externally threaded portion 21 . At this time, the lock button 29 is operated so that the lock nut 28 is rotated rightward as viewed from the front surface side of the lock nut 28, that is, viewed from the lower side in FIG. the

To connect the extension shaft portion 51 to the main body shaft 17 , the lock button 29 is operated so that the extension shaft portion 51 is similarly turned rightward to be screw-coupled to the main body shaft 17 into a state of restricting the rotation of the main body shaft 17 . In addition, in order to connect the grindstone wheel 23 to the main body shaft 17 , the bushing portion of the grindstone wheel 23 is fitted to the end portion of the extended shaft portion 51 so that the lock nut 28 is screw-coupled to the externally threaded portion 55 . And at this time, the rotation of the main body rotating shaft 17 is restricted by the lock button 29, and the lock nut 28 rotates to the right. In this way, when the dust collection fan 31 is coupled to the main body shaft 17 via the extension shaft portion 51, and furthermore, when the dust collection cover 32 is held to the power tool main body 10a, the type of the disc grinder 10 is a dust collection type . Since the grindstone wheel 23 is connected to the main body shaft 17 via the extended shaft portion 51, the length of the threaded portion required for the connection in the axial direction can be fully assured and the connection can be made accurately. Further, even if the blade portion 31b of the dust collecting fan 31 is thick, screw coupling can be sufficiently performed, so when accurate connection is achieved, the amount of air used for dust collection can be increased. the

When the grinding stone wheel 23 is separated from the disc grinder 10 which has held the dust collection adapter 20, the lock nut 28 is turned in the loosening direction. At this time, in some cases, the screw coupling of the internal thread portion 54 of the extension shaft portion 51 and the external thread portion 21 of the main body shaft 17 may be loosened, but the lock nut 28 may not be loosened. In addition, because when the worker presses the lock button 29 with one hand, he turns the lock nut 28 with the other hand, this operation is not easy because the lock nut 28 is separated from the external thread portion 21 of the main body shaft 17 The lock button 29 and the lock nut 28 are located farther from each other than in the case of . the

Therefore, in the tip portion of the extended shaft portion 51 , the recessed portion 56 opened at the tip surface of the extended shaft portion 51 is formed as a rotation restricting portion. As shown in FIG. 8B, the recessed portion 56 is formed as a hexagonal hole, and a connecting/separating jig 57 having a hexagonal outer peripheral surface is engaged with the hexagonal hole. FIG. 4 shows a state where the connecting/disconnecting jig 57 is engaged with the recessed portion 56 serving as a rotation restricting portion. A plurality of recesses 58 are formed in the end face of the lock nut 28 at the same radial position from the center of rotation as each other, and a connecting/detaching jig 59 can be engaged with the recesses 58 as shown in FIGS. 4 and 5 . In the connection/detachment jig 59, a protrusion 59a that engages with the recessed portion 58 is provided. the

In the state where the connecting/separating jig 57 is engaged with the recessed portion 56 and the protrusion 59a of the connecting/separating jig 59 is engaged with the recessed portion 58 as shown in FIG. While the rotation of the extension shaft portion 51 is restricted, the lock nut 28 is rotated in the leftward direction of FIG. 5 corresponding to the loosening direction by the connecting/detaching jig 59 . In this way, the lock nut 28 can be easily separated from the externally threaded portion 55 of the extension shaft portion 51 without rotating the extension shaft portion 51 relative to the main body shaft 17 . At this time, since the lock nut 28 can be loosened by turning the lock nut 28 to the left relative to the extension shaft portion 51 in FIG. rotated, or both can be rotated simultaneously. the

FIG. 6 shows the disc grinder 10 in a state where the grinding stone wheel 23 is separated from the extended shaft portion 51 and the extended shaft portion 51 is separated from the main body shaft 17 . When the extension shaft part 51 is separated from the main body shaft part 17 in the state where the grindstone wheel 23 is separated from the extension shaft part 51, the lock button 29 is pressed so as to restrict the rotation of the main body shaft part 17, and the extension shaft part 51 is turned leftward . At this time, the extended shaft portion 51 can be operated to rotate leftward by the attaching/detaching jig 57, or can be rotated leftwardly while a worker holds the bushing portion 31c of the dust collecting fan 31 by hand. When the extension shaft part 51 is screw-coupled to the main body shaft 17, the extension shaft part 51 can be rotated to the right by the connection/detachment jig 57, or when the worker holds the bushing part 31c of the dust collecting fan 31 by hand The extension shaft portion 51 can be turned rightward. the

Each of FIGS. 9A-13B shows a modified example of the extended shaft portion 51 . In the end portion of the extended shaft portion 51 shown in FIGS. 9A and 9B, an inline concave groove, ie, a minus sign groove 56a extending in the radial direction, is provided as a rotation restricting portion. In the end portion of the extended shaft portion 51 shown in FIGS. 10A and 10B , a cross-shaped concave groove, that is, a plus groove 56b, is provided as a rotation restricting portion. Therefore, in order to connect the lock nut 28 to the extended shaft portion 51 as shown in FIGS. 9A and 9B or to separate the lock nut 28 from the extended shaft portion 51, the member engaged with the minus groove 56a serves as a connecting/separating jig. To connect the lock nut 28 to the extension shaft portion 51 as shown in FIGS. 10A and 10B or to separate the lock nut 28 from the extension shaft portion 51, the member engaging the plus groove 56b serves as a connection/detachment jig. the

In the end portion of the extension shaft portion 51 shown in FIGS. 11A and 11B , a hexagonal protrusion 56 c is provided as a rotation restricting portion so as to protrude from the end surface of the extension shaft portion 51 . In the end portion of the extension shaft portion 51 shown in FIGS. 12A and 12B , a square protrusion 56 d is provided as a rotation restricting portion so as to protrude from the end surface of the extension shaft portion 51 . In the end portion of the extended shaft portion 51 shown in FIGS. 13A and 13B , a protrusion 56 e is provided so as to protrude from the end portion of the extended shaft portion 51 to pass through in the radial direction with respect to the central axis of rotation of the extended shaft portion 51 . The hole 56f is placed in the protrusion 56e serving as a rotation restricting portion. Therefore, in order to connect the lock nut 28 to the extended shaft portion 51 as shown in FIGS. 11A and 11B or to separate the lock nut 28 from the extended shaft portion 51 , a wrench or the like is used as a connecting/separating jig. To connect the lock nut 28 to the extension shaft portion 51 as shown in FIGS. 13A and 13B or to separate the lock nut 28 from the extension shaft portion 51, the rod member passing through the through hole 56f serves as a connection/detachment jig. the

In this way, when the rotation restricting portion is used to restrict the rotation of the extension shaft portion 51, as long as the connecting/detaching jig can be engaged with the extension shaft portion 51, any shape can be adopted, such as a recessed portion, a protrusion, and a through A shape obtained by forming a through hole in a protrusion. Furthermore, the shape of the lock nut 28 is not limited to the shape obtained by forming a plurality of recessed portions 58 on its end face, and a lock nut 28 having a square or hexagonal outer peripheral surface may be used. the

14 is a cross-sectional view showing a modified example of the disc grinder, and FIG. 15 is a view showing disc grinding in a state where the dust collection adapter 20 and the dust collection fan 31 are separated from the power tool main body 10a shown in FIG. 14 Cutaway view of the machine. the

As shown in FIG. 14, in the periphery of the holder 41, a plurality of engagement stoppers 41a are provided at predetermined intervals in the circumferential direction. Inside the tool cover 36, a plurality of engagement grooves 36a that engage with the engagement stopper 41a are provided. By engaging the contact of the stopper 41a with the stopper 36b, the protruding movement of the skirt member 40 pressed by the compression coil spring 42 is restricted. Also in the holder 41 shown in FIG. 2 , an engagement stopper that engages with an engagement groove formed in the tool cover 36 is formed. the

The threaded shaft portion 51 a is fixed to the bush portion 31 c of the dust collecting fan 31 . As shown in FIG. 14 , in the threaded shaft portion 51 a , an internally threaded portion 54 threadedly coupled to the externally threaded portion 21 of the main body shaft 17 is formed. In the threaded shaft portion 51a, an externally threaded portion 55 protruding from the bushing portion 31c is formed. Therefore, when the above-mentioned extended shaft portion 51 is formed by a member different from the dust collection fan 31 so that the extended shaft portion 51 can be separated from the dust collection fan 31, the threaded shaft portion 51a having a structure corresponding to that of the extended shaft portion 51 is fixed to On the dust collecting fan 31 shown in Fig. 14 and 15. The threaded shaft portion 51a configures an extended shaft portion. the

In this way, the type of disc grinder 10 shown in FIG. 14 is a dust collecting type, as shown in FIG. 21, the grinding stone wheel 23 is then connected to the externally threaded portion 55 of the threaded shaft portion 51a, thereby fastening the lock nut 28 to the externally threaded portion 55. On the other hand, the dust collection fan 31 is not connected to the main body shaft 17, but the grindstone wheel 23 is directly connected to the external threaded part 21, and the type of the disc grinder 10 thus obtained is a simple type, as shown in Figure 3 shown. the

14 is fixed to the dust collection fan 31, so that when the dust collection fan 31 is separated from the main body shaft 17, the threaded shaft portion 51a is separated from the main body shaft 17 as shown in FIG. the

The threaded shaft portion 51a shown in FIG. 14 is made of metal material, and the dust collecting fan 31 is made of resin material. When the dust collecting fan 31 is molded by a mold, the threaded shaft portion 51 a is provided inside the mold, and the threaded shaft portion 51 a is molded together with the dust collecting fan 31 . However, by integrally molding the threaded shaft portion 51a and the dust collecting fan 31 from light metal material or resin material by a mold, the dust collecting fan 31 having an integral structure including the threaded shaft portion 51a is obtained. the

At the end of the threaded shaft portion 51a, a recessed portion 56 serving as a rotation restricting portion and engaged with a connecting/disconnecting jig 57 is formed. As the rotation restricting portion, as long as the connection/detachment jig 57 can be engaged therewith, as shown in FIGS. . the

16 is a sectional view showing a modified example of the dust collecting adapter, FIG. 17 is a bottom view showing a disc grinder holding the dust collecting adapter shown in FIG. 16 , and FIG. 18 is a perspective view of the disc grinder. 17 and 18 show the dust collection adapter 20 in a state where the grinding stone wheel 23 is separated from the extended shaft portion 51 . FIG. 16 shows a state in which an extended shaft portion 51 serving as a threaded shaft portion is attached to the dust collecting fan 31 . the

As shown in FIG. 16 , between the holder 41 and the partition wall 35 , a plurality of leaf springs 43 serving as spring members are held at equal distances in the circumferential direction so that Spring force is applied to the skirt member 40 . One end of each leaf spring 43 is fixed to the partition wall 35 , and the other end thereof abuts against the holder 41 . Each plate spring 43 extends from one end to the other end along the inner peripheral surface of the dust collecting cover 32 in the rotation direction of the grindstone wheel 23, and is also inclined toward the front of the dust collecting cover 32. In the dust collection adapter 20 shown in FIG. 16, five leaf springs 43 are provided. the

In the holder 41, 12 guide members 44 protruding radially inwardly from its inner peripheral surface are integrally provided in a rib shape. The length of the protrusion of each guide member 44 in the radially inward direction is shorter than the length of the protrusion of each leaf spring 43 in the radially inward direction. As shown in FIG. 17 , each guide member 44 extends along the inner peripheral surface of the holder 41 in the circumferential direction, and is shown along an arrow in a direction approaching from the opening side of the dust collecting cover 32 to the partition wall 35 side. The rotation direction of the dust collection fan 31 is inclined, that is, each guide member 44 is inclined such that each guide member 44 approaches the suction port 35a. The height of each guide member 44 from the inner peripheral surface of the holder 41 to the radially inner protrusion is different from one end to the other. In addition, all 12 guide members 44 have the same shape, they are arranged at equal intervals in the circumferential direction, and adjacent guide members 44 are arranged to be offset from each other in the circumferential direction so as to be viewed from the axial direction of the main body rotation shaft 17 , they do not overlap each other. In this way, the holder 41 integrally provided with the guide member 44 can be easily molded by using a pair of molds for injection molding which are divided in the axial direction, and therefore, a mold having a complicated structure is not required, This can reduce the manufacturing cost of the dust collecting cover 32 including this holder 41 . the

FIG. 19 is a cross-sectional view showing the inclination angle of each leaf spring 43 and guide member 44 in the circumferential direction. As shown in FIG. 19 , the inclination angle "A" of the plate spring 43 is set larger than the inclination angle "B" of the guide member 44 . Even when the leaf spring 43 is elastically deformed, the holder 41 moves to the stroke edge toward the partition wall 35, the inclination angle A of the leaf spring 43 is set not smaller than the inclination angle B of each guide member 44. the

As shown in FIGS. 17 and 18 , a mesh member 61 is provided on the front surface of the partition wall 35 as a protector. The mesh member 61 includes: an annular portion 62 having a diameter smaller than the inner diameter of the suction port 35a, and a plurality of ribs 63 that extend from the outer periphery of the partition wall 35 when bent in the rotation direction of the dust collecting fan 31. Partially extends toward the annular portion 62 . Each rib 63 is formed integrally with the annular portion 62 in an arc shape, and a radially inner portion of each rib 63 protrudes to the front of the suction port 35a. In the partition wall 35 , the number 12 of ribs 63 is smaller than the number 15 of blades 15 of the dust collecting fan 31 , ie, the number of blade portions 31 b , and 12 ribs 63 are arranged equidistantly in the circumferential direction of the dust collecting cover 32 . The front surface of the mesh member 61 protrudes forward beyond the front surface of the partition wall 35 . the

In this way, since the mesh member 61 includes the annular portion 62 and the plurality of ribs 63, and the plurality of ribs 63 protrude radially inward from the front surface frame portion of the partition wall 35, the mesh member 61 has the function of guiding dust. Flow adjustment function. By forming the mesh member 61 integrally with the dust collecting cover 32, the dust collecting cover 32 having an adjustment function can be manufactured at low cost. Since the end portions of the plurality of ribs 63 on the inner peripheral side are coupled to each other by the annular portion 62, the strength of the mesh member 61 is increased, and thus the durability and operational reliability of the dust collecting cover 32 can be improved. the

The mesh member 61 overlaps the outer peripheral portion of the suction port 35a. Therefore, even if a relatively large foreign matter is sucked into the suction port 35a, such as concrete fragments generated by grinding the part to be ground at the time of the grinding process, the foreign matter can be captured by the mesh member 61 . In this way, the entry of foreign matter into the dust collecting fan 31 from the suction port 35a is prevented. the

When the radially outer portion of each rib 63 has a rectangular cross-sectional shape with respect to the partition wall 35, a part of each rib 63 has a gap at its end opposite to the dust collecting fan 31 with respect to the cross-sectional shape of the suction port 35a. As for the arc portion 63a shown in FIG. Therefore, the vortex flowing from the grindstone wheel 23 side to the dust collecting fan 31 is smoothly guided to the dust collecting fan 31 so as to flow in the axial direction relative to the dust collecting fan 31 through the arc portion 63 a of each rib 63 . In this way, with this dust collecting fan 31, the suction efficiency is improved. Arrow "C" in Fig. 20 indicates the flow of intake air. the

When the dust collection cover 32 is held on the disc grinder 10, the entire grinding stone wheel 23 is covered by the dust collection cover 32, and in addition, the rear surface of the grinding stone wheel 23 opposite to the grinding surface of the grinding stone wheel 23 is covered by a partition wall. 35 and mesh member 61 cover. When the motor 12 is started in a state where the dust collecting cover 32 is held to the disc grinder 10, the dust collecting fan 31 rotates together with the grindstone wheel 23 to generate a suction force at the suction port 35a. When the grindstone wheel 23 is pressed onto a material to be ground such as concrete or tiles for grinding processing, dust such as grinding powder is radially scattered from the outer peripheral portion of the grindstone wheel 23 to the outside. The scattered dust is blocked by the skirt member 40 from leaking outward, and is captured inside the tool cover 36 . The dust trapped inside the tool cover 36 is sucked into the fan housing chamber 37 from the suction port 35 a by the suction force of the dust collection fan 31 , passes through the scroll flow path 38 , and is discharged from the discharge duct 39 . The discharged dust is collected in a dust bag (not shown) provided at the end of the discharge duct 39 . the

The dust generated by the grinding of the grindstone wheel 23 spreads from the outer peripheral portion of the grindstone wheel 23 to its tangential direction, and when it is vortexed inside the tool cover 36, it passes through the middle of the outer peripheral portion of the grindstone wheel 23 and the holder 41, And it is sucked toward the suction port 35a. At this time, on the inner peripheral surface of the holder 41, a guide member 44 is provided so as to extend along the dust flow and be inclined with respect to the circumferential direction. Therefore, the dust flows along these guide members 44, and the dust is guided by the guide members 44 to flow toward the suction port 35a in the axial direction when the grindstone wheel 23 rotates in the same direction. That is, dust flows spirally inside the tool cover 36 . the

The dust flow after passing the outer peripheral portion of the grindstone wheel 23 and the middle of the holder 41 passes through the middle of the leaf spring 43 . Since these leaf springs 43 are also arranged to extend along the dust flow and are inclined with respect to the circumferential direction, the dust flows along the leaf springs 43, thus guiding the dust through the leaf springs 43 to enhance the swirl flow to the rotation direction of the dust collecting fan 31. , so that the dust flows toward the suction port 35a in the axial direction. Even if the skirt member 40 is moved vertically according to the roughness of the material 50 to be ground, the eddy current of the dust will not be weakened by being guided by the leaf springs 43 because the inclination angle A of each leaf spring 43 is not less than that of each guide member 44. inclination angle B. the

Then, the dust vortex reinforced by the guide member 44 and the leaf spring 43 flows along the rib 63 and is guided to the suction port 35a. These ribs 63 extend along the rotation direction of the dust collecting fan 31 and are also bent toward the axial center of the dust collecting fan 31 , so that the dust flow is guided toward the center of the dust collecting fan 31 when the vortex is further enhanced by the ribs 63 . Further, the dust flow flowing into the vortex flow path 38 from the suction port 35a is guided by the annular portion 62 coupled to the end of the rib 63, and directed toward the axial direction of the dust collecting fan 31 (inflow direction). Since each guide member 44, plate spring 43 and rib 63 are equidistantly arranged in the circumferential direction, dust flows from the suction port 35a into the scroll flow path 38 while maintaining a substantially uniform flow with respect to the circumferential direction. the

Along with passing through the middle of each vane portion 31b, after the dust flows into the vortex flow path 38 from the suction port 35a, it is discharged radially outward by the rotational force of the dust collection fan 31, through the vortex flow path 38, from the discharge duct 39 Exhausted and collected in a dust bag (not shown). In this way, inside the dust collecting cover 32, when in the same direction as the rotation direction of the dust collecting fan 31, by the rotation of the guide member 44, the leaf spring 43 and the rib 63 provided on the holder 41, The flow of dust discharged from the grindstone wheel 23 flows into the vortex flow path 38, so the dust collection efficiency of the dust collection fan 31 can be improved. Therefore, the dust collection efficiency of the dust collection fan 31 can be improved without manufacturing the dust collection fan 31 on a large scale, and the dust discharged from the grindstone wheel 23 can be further efficiently collected. the

Because the number of ribs 63 is different from that of the blade portions 31b of the dust collection fan 31, for each blade portion 31b, a gap is generated between each blade portion 31b of the dust collection fan 31 and each rib 63. Each phase of pressure fluctuations is offset from the other. In this way, noise resonance due to pressure fluctuations is blocked, so that the noise of the dust collecting cover 32 can be reduced. the

The mesh member 61 including the ribs 63 and the annular portion 62 is provided to the suction port 35a of the dust collecting cover 32, so that even if a large foreign matter such as a concrete block that is ground in the grinding process accidentally enters the surface of the dust collecting cover 32 Inside, foreign matter can also be captured by the mesh member 61 . In this way, foreign matter can be prevented from entering the scroll flow path 38 from the suction port 35a. Therefore, the operation reliability of this dust collecting cover 32 can be improved by preventing the rotation of the dust collecting fan 31 from being hindered or damaged by foreign matter generated by grinding the material 50 to be ground during the grinding process. the

FIG. 21 shows a modified example of the mesh member 61 provided to the dust collecting cover 32 . The mesh member 61 includes: an outer ring portion 62a; and an inner ring portion 62b having a diameter smaller than that of the outer ring portion 62a. The diameter of the inner ring portion 62a is smaller than that of the ring portion 62 shown in FIG. 17 . An intersecting ribbon portion 64 having a grid pattern is disposed between the two loop portions 62a and 62b. A plurality of ribs 63 are provided to the outer ring portion 62a in a similar manner to the ribs shown in FIG. 17 . The strength of the mesh member 61 can be increased by providing the mesh member 61 with the intersecting belt-like portion 64 in a lattice pattern. the

FIG. 22 shows still another modified example of the mesh member 61 provided to the dust collecting cover 32 . The mesh member 61 has an annular protective plate 66 in which twelve circular through holes 65 are formed equidistantly. The rib 63 is provided to the protection plate 66 in a manner similar to that provided to the rib shown in FIG. 17 . By forming the mesh member 61 using this protective plate 66, the mesh member 61 can be provided to have a simple and strong structure. The mesh member 61 shown in FIGS. 21 and 22 may be made of a resin material so as to be integrally formed with the casing half 32b of the dust collecting cover 32, or the mesh member 61 may be made of resin metal so as to be formed separately with the dust collecting cover 32. The housing half 32 b is a separate component and is connected to the partition wall 35 . the

FIG. 23 is a sectional view showing a disc grinder 10 provided with a modified example of a dust collection adapter, and FIG. 24 is a bottom view of FIG. 23 . FIG. 25 is a side view showing a recessed portion provided to the holder, and FIG. 26 is a perspective view showing the holder and a peripheral portion connected thereto. the

Four engaging grooves 36a are formed in the dust collecting cover 32, and engaging stoppers 41a engaged with the respective engaging grooves 36a are provided to the holder 41 made of resin. As shown in FIG. 25, the engaging groove 36a includes: a first recessed portion 71a opened at the front end surface of the dust collecting cover 32, and a second recessed portion 71b distant from the first recessed portion 71a in the circumferential direction, The first recessed portion 71a and the second recessed portion 71b communicate with each other through the guide recessed portion 71c. In the second recessed portion 71b, a stopper surface 71d for supporting the engagement stopper 41a is provided. In this way, in order to connect the holder 41 to the dust collecting cover 32, the spring force of the compression coil spring 42 in the state where the engagement stopper 41a and the first recessed portion 71a are engaged is opposite, and the holder 41 is Push or insert into the dust cover 32. And, the holder 41 is turned until the engaging stopper 41a reaches the position of the second recessed portion 71b through the guide recessed portion 71c in a state where the engaging stopper 41a is close to the guide surface 71e of the guide recessed portion 71c. When the pushing force on the holder 41 is released in this state, the engagement stopper 41a abuts on the stopper surface 71d of the second recessed portion 71b. In this way, the retainer 41 is held on the dust collecting cover 32 and thus prevented from being separated from the dust collecting cover 32 . In this way, by engaging the engagement stopper 41a with the engagement groove 36a, the holder 41 can be attached to the dust collecting cover 32 accurately and easily. The holder 41 is vertically movable with respect to the dust collecting cover 32 in a state where the engaging stopper 41 a in the second recessed portion 71 b is biased by spring force. the

In the holder 41, as shown in FIG. 26, a connection groove 41b holding the skirt member 40 is formed on one end surface thereof, and a protrusion holding a compression coil spring 42 is provided on the other end surface thereof as shown in FIG. part 41c. The skirt member 40 is formed in a ring shape, and both ends of the felt and belt-like fabric material are adjoined to each other. The thickness of the skirt member 40 is set larger than the width of the connection groove 41b41, and when the skirt member 40 is pushed into the connection groove 41b, the skirt member 40 is fixed to the holder 41. The front end surface of the skirt member 40 fixed to the holder 41 protrudes forward beyond the front surface of the grindstone wheel 23 . the

When the grinding process is performed by the disc grinder 10, the skirt member 40 protrudes beyond the front surface of the grinding stone wheel 23, so the skirt member 40 is pressed against the material 50 to be ground by the spring force of the compression coil spring 42, so that A space is prevented from being formed between the skirt member 40 and the material 50 to be ground. In this state, the grinding stone wheel 23 is rotationally driven in the direction indicated by the arrow in FIG. 24 so that the disc grinder 10 moves along the surface of the material 50 to be ground. At this time, as shown in FIGS. 28A and 28B, even if there is a protruding portion 50a on the surface of the material 50 to be ground, it is possible to avoid creating a gap in a part of the skirt member 40 that is in contact with the protruding portion 50a, because the adjacent portion Apart from 40a, the skirt member 40 is continuously formed in a continuous shape. In this way, dust flow and the like are prevented from entering into the fan housing chamber 37 . the

Since the skirt member 40 is press-fitted into the connection groove 41 b to be held to the holder 41 , the work of connecting the skirt member 40 to the holder 41 can be simplified. Since the manufacturing cost of the skirt member 40 made of fabric is lower than that of a brush or the like, even if the skirt member 40 is frequently replaced with a new peripheral member, an increase in its maintenance cost can be avoided. Because the air sucked by the dust collection fan 31 flows into the fan accommodating chamber 37 from the suction port 35a, and is discharged to the discharge duct 39, the pressure in the area where the discharge duct 39 communicates with the fan accommodating chamber 37 is reduced to the greatest extent. The skirt member 40 is held to the connecting groove 41b so as to position the adjacent portions at both ends thereof to match the portion where the suction force is optimum, which is the area where the discharge duct 39 communicates with the fan housing chamber 37 . If the adjoining portion 40a is not sewn or glued carefully, a slight gap may be produced in some cases. However, as shown in FIG. 24, by disposing the abutting portion 40a at a position where the suction force is optimal, it is possible to prevent dust and the like from being discharged to the outside from the abutting portion 40a. the

Since the holder 41 is held on the dust collecting cover 32 in a state where the skirt member 40 has been connected to the holder 41 before, the skirt member 40 can be easily held to the dust collecting cover 32 . Since the rigidity of the skirt member 40 can be maintained by the holder 41, even if the skirt member 40 contacts the material to be ground 50 such as a concrete surface to apply an external force thereto, the annular shape of the skirt member 40 can be precisely maintained. Since the skirt member 40 is inserted and fixed to the connection groove 41 b of the holder 41 , it is possible to easily connect the skirt member 40 to the holder 41 . Even if the skirt member 40 is worn out by grinding, it can be easily replaced with a new skirt member 40, so the maintenance performance of the disc grinder 10 can be improved. the

FIG. 29A is a bottom view showing a skirt member 40 of a modified example, and FIG. 29B is a sectional view taken along line 29B-29B in FIG. 29A . the

As shown in FIGS. 29A and 29B, in the holder 41, an engagement stopper 72 protruding into the connection groove 41b is provided. When the skirt member 40 is pressed into the connection groove 41b, the engagement stopper 72 bites the skirt member 40 to prevent the skirt member 40 from coming off from the connection groove 41b. In this way, the skirt member 40 can be accurately fixed to the holder 41 . The recessed portion into which the engagement stop 72 slides into the skirt member 40 may be previously formed. the

FIG. 30A is a bottom view showing a skirt member 40 of still another modified example, and FIG. 30B is a sectional view taken along line 30B-30B of FIG. 30A . the

The skirt member 40 shown in FIGS. 30A and 30B is formed by laminating three fabrics. In this way, by laminating a plurality of fabrics, the skirt member 40 can be formed. the

FIG. 31 is a front view showing a part of a skirt member 40 of still another modified embodiment. In the skirt member 40, the cord 73 is braided into a part of the skirt member 40 protruding from the holder 41 in two routes. By weaving the strands 73 into the skirt member 40, the strength and flexibility of the skirt member 40 can be tuned to desired properties. the

Fig. 32 is a partially cutaway front view showing a disc grinder holding a dust collection adapter of yet another modified embodiment. 33 is a bottom view of FIG. 32 , and FIG. 34 is an enlarged sectional view showing a part of the skirt member shown in FIG. 33 and a holder connecting the skirt member. the

Although the above-mentioned skirt member 40 is formed of a belt-like fabric, as shown in FIG. 33 , this skirt member 40 may also be formed of a plurality of fabric sheet-like members 74 . In the holder 41, a plurality of connection grooves 41b connected to the respective sheet members 74 may be formed. The length of the sheet member 74 is almost equal to the length of the connection groove 41b, and the sheet member 74 is formed in a strip shape so that its thickness is greater than the width of the connection groove 41b. As shown in FIG. 34 , the sheet-like member 74 is held onto the connection groove 41 b so that a portion thereof on one side in the width direction protrudes from the front surface of the holder 41 . the

Each sheet member 74 is inclined with respect to the tangential direction of the radius of the dust collecting fan 31 , forming a downstream portion in the rotation direction of the dust collecting fan 31 radially inwardly from its upstream portion to the downstream portion. In the downstream portion of the sheet member 74, a tapered portion 74a whose tip portion is tapered is formed, and the tapered portion 74a overlaps with the bottom end portion of another sheet member 74 to sandwich a space therebetween. In this way, a space is formed between overlapping portions of the two sheet members 74 adjacent to each other, and a plurality of transfer flow paths 75 are formed in the skirt member 40, as shown by arrows in FIG. Through a plurality of transfer flow paths 75 . the

Each of the plurality of transfer flow paths 75 is inclined so as to be included in the vortex generated by the grindstone wheel 23 by the rotation of the dust collection fan 31 , so air is drawn in from the outside and flows into the skirt member 40 . In this way, a large amount of air is guided into the fan housing chamber 37 . Since each sheet member 74 is overlapped with another sheet member 74 to sandwich a space between them at both end portions in the longitudinal direction, the radially outward spreading by the grindstone wheel 23 is prevented. Dust comes out of the skirt member 40 . The length and flow path cross-sectional area of each of the plurality of conveyance flow paths 75 , and the inclination angle of each of the plurality of conveyance flow paths 75 are set according to the grinding performance of the grindstone wheel 23 and the suction performance of the dust collecting fan 31 . the

FIG. 35 is a bottom view showing a disc grinder 10 provided with a skirt member 40 of a modified embodiment. This skirt member 40 is formed of a plurality of sheet members 74, and generally the thicknesses of the plurality of sheet members 74 are the same in their longitudinal directions. the

FIG. 36 is a sectional view showing a modified embodiment of a skirt member 40 formed so as to laminate a plurality of fabric materials for each sheet member 74 . Each sheet member 74 may be formed by laminating fabric materials, resin sheets, metal brushes. the

Fig. 37 is a bottom view showing a disc grinder holding a dust collection adapter of yet another modified embodiment. This skirt member 40 is formed of a plurality of sheet members 74 continuously connected to the connection groove 41b via spaces so as to sandwich the spaces therebetween in the circumferential direction. The end face of each sheet member 74 is inclined as shown in FIG. 37 , and a plurality of transfer flow paths 75 are formed with intervals between the end faces of the sheet member 74 . However, the skirt member 40 may be formed of a belt-like fabric, and a plurality of through holes forming a plurality of transfer flow paths may be formed in the skirt member 40 . Furthermore, even if a plurality of transfer flow paths 75 are formed in the skirt member 40 to protrude in the radial direction, dust scattered by the grindstone wheel 23 can be guided by the air flow inside the plurality of transfer flow paths 75, thus preventing The dust is discharged to the outside of the skirt member 40 . the

Hereinbefore, the invention made by the inventors has been specifically described based on the embodiments. However, the present invention is not limited to the above-described embodiments, and various modifications and changes can be made within the scope of the present invention. For example, the illustrated disc grinder 10 is an electric power tool using an electric motor as a drive source, ie, an electric power tool. However, the present invention can also be applied to electric tool types that use a wind motor as a driving source. The shown disc grinder 10 is used for grinding the surface of the material to be ground, so that the surface of the material to be ground can be roughly treated by the grinding process. On the other hand, the finishing process is called "polishing", and the electric tool for polishing is called "disc grinder" or "polisher". The electric tool of the present invention can also be used in a device for performing polishing. the

Claims (20)

1. a control of dust adapter is connected to power tool body, and collects the dust that when the end-of-arm tooling that drives rotationally through the main body rotating shaft by said power tool body is processed material to be ground, produces, and it is characterized in that:

Said control of dust adapter comprises:

The control of dust fan is driven by said main body rotating shaft rotationally; With

Dust collection cover remains on the said power tool body holding said control of dust fan therein, and hides the radially outer of said end-of-arm tooling;

Said control of dust fan comprises fan main body and threaded shank portion, and said fan main body has a plurality of blades; Said threaded shank portion is arranged on the radial center part of said fan main body, and in said threaded shank portion, is formed with the female thread portion of screw thread couple to the male thread portion of said main body rotating shaft; And

Screw thread couple is set at the end of said threaded shank portion to the male thread portion on the clamp structure that is used for fixing said end-of-arm tooling.

2. control of dust adapter according to claim 1 is characterized in that:

Said threaded shank portion is provided with and is used to limit the limit rotation part that said control of dust fan rotates on the direction of rotation at said clamp structure during with respect to the said external thread part component of rotation at said clamp structure.

3. control of dust adapter according to claim 2 is characterized in that:

Said limit rotation partly is the recess such as hex hole, and said recess is meshed at the end surface place opening of the said male thread portion of said threaded shank portion and with being connected/separating anchor clamps, and

Said connection/separately anchor clamps are meshed with said recess, rotate on the direction of rotation of said clamp structure to limit said control of dust fan.

4. control of dust adapter according to claim 2 is characterized in that:

Said limit rotation partly is the prodger such as the hexagon prodger, and said prodger is outstanding and be meshed with being connected/separating anchor clamps from the end surface of the said male thread portion of said threaded shank portion, and

Said connection/separately anchor clamps are meshed with said prodger, rotate on the direction of rotation of said clamp structure to limit said control of dust fan.

5. control of dust adapter according to claim 1 is characterized in that:

Said threaded shank portion is fixed to said fan main body.

6. control of dust adapter according to claim 1 is characterized in that:

Said threaded shank portion and said fan main body integrally form.

7. control of dust adapter according to claim 1 is characterized in that:

Said threaded shank portion is to extend the rotating shaft part, and said extension rotating shaft part removably remains to said fan main body and extends said main body rotating shaft.

8. control of dust adapter according to claim 1 is characterized in that:

Avoid exotic to be arranged on the said dust collection cover from the reticular component that said end-of-arm tooling gets into said control of dust fan.

9. control of dust adapter according to claim 8 is characterized in that:

Said reticular component comprises:

Annular section; With

A plurality of flanks, said a plurality of flanks extend from the interior periphery surface curvature of said dust collection cover and to said annular section on the direction of rotation of said control of dust fan, so that combine with said annular section.

10. control of dust adapter according to claim 8 is characterized in that:

Said reticular component comprises:

First annular section;

Second annular section, the diameter of said second annular section is greater than the diameter of said first annular section; And

A plurality of flanks, said a plurality of flanks extend from the interior periphery surface curvature of said dust collection cover and to said second annular section on the direction of rotation of said control of dust fan.

11. control of dust adapter according to claim 8 is characterized in that:

Said reticular component comprises:

The annular slab member is formed with a plurality of through holes on said annular slab member; And

A plurality of flanks, said a plurality of flanks from the interior periphery surface curvature of said dust collection cover, and extend to combine with said annular slab member to said second annular section on the direction of rotation of said control of dust fan.

12. control of dust adapter according to claim 1 is characterized in that:

Said control of dust adapter also comprises:

Annular keeper is arranged on the terminal part office of said dust collection cover, so that be movably on axis direction;

By the skirt shape member that fabric is processed, said skirt shape member remains on the said keeper, and stops the distribution of the dust that when processing material to be ground, produces; And

Spring member, said spring member are arranged between said keeper and the said dust collection cover, and on the direction that said skirt shape member is given prominence to from the front surface of said dust collection cover, apply spring force to said keeper.

13. control of dust adapter according to claim 12 is characterized in that:

Said skirt shape member remains on the said keeper, so that the two ends of ribbon-shaped members are adjacent to each other, and adjacent part is arranged in the zone corresponding with the exhaust outlet of said dust collection cover.

14. control of dust adapter according to claim 13 is characterized in that:

Said skirt shape member forms through range upon range of a plurality of members.

15. control of dust adapter according to claim 12 is characterized in that:

Radially outward outstanding a plurality of engage stops are arranged on the said keeper, and the link slot that is meshed with each engage stops is formed in the said dust collection cover, and each said link slot comprises:

First recess, the opening at the front surface place of said dust collection cover;

Second recess comprises being used to support said engage stops so that in a circumferential direction away from the stop surfaces of said first recess; With

The guiding recess is coupled said first recess and said second recess mutually.

16. control of dust adapter according to claim 12 is characterized in that:

In said skirt shape member, be formed with a plurality of inside and outside transmission flow paths that interconnect that are used to make said skirt shape member.

17. control of dust adapter according to claim 16 is characterized in that:

Each said transmission flow path tilts from the direction that the outside opening of each said transmission flow path partly squints on the direction of rotation of said control of dust fan along the inside opening of each said transmission flow path part.

18. control of dust adapter according to claim 15 is characterized in that:

Said skirt shape member comprises a plurality of flat members that remain on the said keeper; So that radially inwardly locate in its downstream on the direction of rotation of said control of dust fan; The end of each the said flat member on the said circumferencial direction and on said circumferencial direction the end of another flat member of contiguous said end overlapping between them, to sandwich at interval, so that forms the transmission flow path by said interval.

19. an electric tool carries out attrition process through end-of-arm tooling to material to be ground, it is characterized in that:

Said electric tool comprises:

Power tool body is provided with the main body rotating shaft that is used for driving rotationally said end-of-arm tooling;

The control of dust fan is driven by said main body rotating shaft rotationally; And

Dust collection cover remains on the said power tool body holding said control of dust fan, and hides the radially outer of said end-of-arm tooling;

Said control of dust fan comprises fan main body and threaded shank portion; Said fan main body has a plurality of blades; Said threaded shank portion is arranged on the radial center part of said fan main body; In said threaded shank portion, be formed with the female thread portion of screw thread couple, and in said threaded shank portion, be provided with the male thread portion of screw thread couple to the clamp structure that is used for fixing said end-of-arm tooling to the male thread portion of said main body rotating shaft, and

The dust that when processing material to be ground through said end-of-arm tooling, produces is inhaled in the said dust collection cover.

20. electric tool according to claim 19 is characterized in that:

Said threaded shank portion is to extend the rotating shaft part, and said extension rotating shaft part removably remains to said fan main body and extends said main body rotating shaft.

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