JP2021130253A - Portable cutter - Google Patents

Abstract

To provide a portable cutter including a dust box for collecting cut powder caused by cutting of a siding board and the like and having enhanced operability in installation and removal of the dust box.SOLUTION: Axial force of a joining shaft 61 is generated and released by changing an amount of fastening of a male screw part 63a relative to a second shaft part 64 by rotation operation of an operation part 65. A hooking part 64d is hooked on a shaft holding part 62 with the axial force of the joining shaft 61, and a dust box 50 is joined to the fixing cover 23 side. The dust box 50 is removed by displacing the hooking part 64d in a radial direction by loosening the axial force of the joining shaft 61 to separate the joining shaft 61 from the shaft holding part 62.SELECTED DRAWING: Figure 8

Description

The present disclosure relates to a portable cutting machine. The portable cutting machine includes, for example, a portable circular saw mainly used for cutting wood, a cutter mainly used for grinding stone, and the like.

The portable cutting machine has various measures to prevent the cutting powder generated by the cutting process from being scattered around. Patent Documents 1 and 2 disclose a portable cutting machine in which a dust box for collecting cutting dust is detachably provided by a pinching screw. Patent Document 3 discloses a tip saw cutter provided with a dust box that can be attached and detached by operating a slide lever.

JP-A-2018-94853 Japanese Unexamined Patent Publication No. 2017-35820 JP-A-2007-196310

According to the former dust box mounting structure, in order to attach / detach the dust box, it was necessary to rotate the knob screw in the tightening direction, for example, about 6 to 7 times, or in the loosening direction until the screw was completely removed. .. In this respect, the attachment / detachment operation was troublesome. According to the latter mounting structure of the dust box, the slide lever is held at the mounting position by a spring-forced force. For this reason, there is a problem that the operation of the slide lever becomes stiff due to the biting of cutting powder or the like, and the operability is impaired. Therefore, it is necessary to further improve the operability for attaching and detaching the dust box.

According to one feature of the present disclosure, the portable cutting machine has a cutting machine body that houses an electric motor. The cutting tool is rotated by an electric motor. The cutting powder generated by the cutting tool when cutting the material to be cut is collected in the dust box. The dust box is coupled to the cutting machine body by a coupling mechanism. The coupling mechanism includes a shaft holding portion, a coupling shaft, and an axial force generating portion. The shaft holding portion is provided in either the dust box or the main body of the cutting machine. The coupling shaft is provided with a hooking portion and is radially engaged with the shaft holding portion. Axial force is generated on the coupling shaft by the axial force generating part, and the dust box is pressed against the cutting machine body by the hooking part. The dust box can be removed from the cutting machine body by removing the coupling shaft in the direction intersecting the coupling shaft with respect to the shaft holding portion when the axial force of the coupling shaft is released.

Therefore, by releasing (relaxing) the axial force of the axial force generating portion, the coupling shaft is displaced in the direction intersecting the axis of the coupling shaft, and the hooking portion is separated from the shaft holding portion. As a result, the state of pressing the dust box against the cutting machine main body by the hooking portion is released, and the dust box can be removed. Therefore, the dust box can be removed quickly and easily with a smaller amount of operation (axial force loosening operation) as compared with the conventional configuration in which the knob screw is rotated a plurality of times to remove the screw. In addition, unlike the conventional slide lever, there is no biting of cutting powder or the like, and smooth operability can be maintained.

The operation for generating and releasing the axial force by the axial force generating part is the rotation operation of the operation part around the axis of the coupling axis, and the rotation operation of the lever around the axis orthogonal to the axial direction of the coupling axis is applied. can do.

According to another feature of the present disclosure, the operating portion is provided at the other end on the opposite side of the hooking portion of the coupling shaft. The axial force of the coupling shaft is released by rotating the operation unit around the axis of the coupling shaft. This improves the operability of the coupling shaft. For example, the axial force generating portion can be operated by screwing a screw made by rotating the operating portion. Alternatively, the axial force generating portion can be operated by the displacement of the cam portion around the axis by rotating the operating portion.

According to another feature of the present disclosure, the operating portion has a disc-shaped base portion and two finger hook portions extending in radial directions in opposite directions from the base portion. The axial force generating portion is formed by screwing the male-threaded portion and the female-threaded portion, which are performed by rotating the operating portion. Therefore, it is possible to provide an axial force generating portion in which the axial force is surely generated and released by a simple and inexpensive configuration. Axial force is generated and released by hooking a finger on the finger hook of the operation unit and rotating it. As a result, the axial force generating portion can be operated quickly and easily without using a special tool.

According to another feature of the present disclosure, the coupling shaft has a first shaft portion having an operation portion and a male screw portion, and a second shaft portion having a female screw portion and a hook portion. Therefore, the male threaded portion of the first shaft portion and the female threaded portion of the second shaft portion are screwed together to form the axial force generating portion. The axial force can be changed by rotating the operation unit to rotate the first shaft unit around the axis.

According to another feature of the present disclosure, a second shaft portion having a hooking portion is non-rotatably engaged with the dust box. Therefore, the first shaft portion having the operation portion is rotatably supported by the dust box. By rotating the first shaft portion via the operation portion, the screwing positions of the male screw portion and the female screw portion change. The axial force of the coupling shaft changes as the screwing positions of the male screw portion of the first shaft portion and the female screw portion of the second shaft portion change.

According to another feature of the present disclosure, the second shaft portion is non-rotatably engaged with the dust box via the hexagonal shaft portion. An engaging shaft portion having a diameter smaller than that of the hook portion is provided on a part of the hexagonal shaft portion in the axial direction. The engaging shaft portion is made to enter the shaft holding portion, and the hooking portion is hooked on the shaft holding portion. Due to the simple and inexpensive configuration, the hooking portion is hooked on the shaft holding portion without rotating.

According to another feature of the present disclosure, the hooked state of the hooked portion with respect to the shaft holding portion is released by the displacement of the coupling shaft in the direction intersecting the coupling shaft. Displacement of the coupling shaft in the direction intersecting the coupling shaft is allowed only when the loosening of the axial force of the coupling shaft is greater than the setting due to the displacement regulating protrusion.

By rotating the first shaft portion via the operation portion, the axial force of the coupling shaft is relaxed. For example, it is assumed that the operation unit rotates due to vibration or the like regardless of the rotation operation, and the axial force is loosened. Even in this case, if the looseness of the axial force is smaller than the set value, the displacement of the coupling shaft in the direction intersecting the coupling shaft is regulated by the displacement regulating protrusion. As a result, the coupling shaft is restricted from being detached from the shaft holding portion, and the dust box is prevented from being inadvertently removed. The coupling axis can be displaced in the direction intersecting the coupling axis on condition that the looseness of the axial force becomes larger than the set value by the operation of the user. Therefore, the dust box can be removed by separating the coupling shaft from the shaft holding portion.

According to another feature of the present disclosure, a shaft holder is formed on the cutting machine body. Therefore, the hooked portion of the coupling shaft is hooked on the shaft holding portion on the cutting machine main body side, and the dust box is pressed against the cutting machine main body. The shaft holding portion can also be formed on the dust box side.

According to other features of the disclosure, the coupling shaft is irremovably supported by the dust box. Therefore, the loss of the coupling shaft is prevented, and it is not necessary to separately prepare the dust box when it is attached, so that the workability of attaching and detaching the dust box can be improved.

According to another feature of the present disclosure, the portable cutting machine has a cutting machine main body for accommodating an electric motor, a cutting tool, a dust box, and a coupling mechanism. The cutting tool is rotated by the electric motor. The cutting powder generated by the cutting tool when cutting the material to be cut is collected in the dust box. The dust box is coupled to the cutting machine body by the coupling mechanism. The coupling mechanism includes a coupling shaft, a hooking portion, a shaft holding portion, and a displacement regulating protrusion.

Due to the axial displacement of the coupling shaft, the hooking portion is hooked on the shaft holding portion, and the dust box is coupled to the cutting machine main body. The coupling shaft is separated from the shaft holding portion by being displaced in a direction intersecting the coupling shaft. As a result, the pressing of the hooking portion is released, and the dust box can be removed from the cutting machine main body. For this reason, the dust box can be removed quickly and easily with a smaller amount of operation as compared with the conventional configuration in which the knob screw is rotated a plurality of times to remove the screw.

Even if the coupling shaft is displaced in the axial direction due to vibration or the like, it is assumed that the displacement amount is about rattling (looseness) smaller than the set value. In this case, the displacement of the coupling shaft in the direction intersecting the coupling shaft is regulated by the displacement regulating protrusion. Therefore, careless removal of the dust box is prevented. The dust box can be removed by detaching the coupling shaft from the shaft holding portion on condition that the axial displacement of the coupling shaft becomes larger than the setting by the user's operation.

According to other features of the present disclosure, the direction intersecting the coupling axis can be the radial direction orthogonal to the coupling axis. By displacing the coupling shaft in the radial direction orthogonal to the axis, the coupling shaft can be efficiently separated from the shaft holding portion.

It is a right side view of a portable cutting machine. FIG. 1 is a view taken along the line II of FIG. 1, which is a plan view of a portable cutting machine. FIG. 3 is a view taken along the line III of FIG. 1, which is a front view of a portable cutting machine. FIG. 1 is a rear view of the IV arrow view of FIG. 1, which is a rear view of a portable cutting machine. It is a V arrow view of FIG. 3, and is the left side view of the portable cutting machine. It is a right side view of the portable cutting machine with the dust box removed. It is a split perspective view of a dust box. This figure shows the state seen from the diagonally rear right side. It is a split perspective view of a dust box. This figure shows the state seen from the diagonally rear left side. FIG. 8 is a left side view of the fixed cover as viewed from the direction of arrow IX in FIG. It is a perspective view of a dust box. It is a right side view which looked at the dust box in the direction of arrow XI in FIG. It is a left side view which looked at the dust box in the direction of arrow XII in FIG. FIG. 1 is a sectional view taken along line VIII-VIII in FIG. 1 and is a vertical sectional view of a coupling mechanism. It is an enlarged view of the XIV part in FIG. 13, and is the enlarged view of the coupling mechanism. It is a figure which shows the detached state of the 2nd shaft part with respect to the shaft holding part.

Next, an embodiment will be described with reference to the attached drawings. As shown in FIGS. 1 to 5, in the present embodiment, as an example of the portable cutting machine 1, a hand-held cutting machine, which is also called a dust-proof circular saw, is illustrated. This portable cutting machine 1 is used, for example, for cutting siding, masonry boards, and the like at a construction site of a house. The user is located on the rear side in FIG. The cutting process proceeds when the user moves the portable cutting machine 1 forward. In the following description, for each direction of the member and the configuration, the direction in which the cutting proceeds is the front side, and the side in which the user is located is the rear side. The user is the standard for the left-right direction.

The portable cutting machine 1 includes a rectangular flat plate-shaped base 10 that comes into contact with the upper surface of the material W to be cut, and a cutting machine main body 20 that is supported on the upper surface side of the base 10. A dust box 50 for collecting dust is attached to the right side of the cutting machine main body 20. The cutting machine main body 20 includes a circular cutting tool 22 called a tip saw that is rotated by an electric motor 21. The periphery of the upper side of the cutting tool 22 is covered with a fixed cover 23. The lower side of the cutting tool 22 protrudes toward the lower surface side of the base 10. The lower side of the cutting tool 22 is covered with a movable cover 26 so as to be openable and closable. The movable cover 26 is urged in the closing direction by the tension spring 26a. By moving the portable cutting machine 1 forward with the movable cover 26 in contact with the material W to be cut, the movable cover 26 is relatively rotated clockwise in FIG. 1 to be opened. The movable cover 26 is opened against the tension spring 26a to expose the cutting tool 22. The exposed portion of the cutting tool 22 is cut into the material W to be cut and the cutting process is performed.

The cutting tool 22 rotates in the counterclockwise direction in FIG. The direction of rotation of the cutting tool 22 is indicated by a white arrow display 56 displayed on the right side surface of the dust box 50 in FIG. The front end portion of the exposed portion of the cutting tool 22 protruding toward the lower surface side of the base 10 is cut into the material to be cut W to perform cutting processing. The portion where the front end portion of the cutting tool 22 is cut into the material W to be cut is the cutting portion C. The cutting powder is blown upward from the cutting site C. The blown-up cutting powder is collected in the dust box 50.

The motor housing 25 is coupled to the left side surface of the fixed cover 23 via the gear housing 24. The gear housing 24 is integrally formed with the fixed cover 23. Although not shown, the gear housing 24 is equipped with a gear train for reducing the rotational output of the electric motor 21. A two-stage reduction gear train of spur gears is used as the gear train.

As shown in FIG. 5, the motor housing 25 is screwed to the left end of the gear housing 24 with four fixing screws 25b. The electric motor 21 is built in the motor housing 25. A DC brushless motor is used as the electric motor 21. The motor axis (axis of the output shaft) J of the electric motor 21 extends in the left-right direction. A plurality of intake ports 25a for introducing outside air for cooling the motor are provided on the left end surface of the motor housing 25.

The rotational output of the electric motor 21 is decelerated by the reduction gear train and output to the final output shaft (spindle, not visible in the figure). The final output shaft protrudes into the fixed cover 23. The cutting tool 22 is attached to the protruding portion of the final output shaft. As shown in FIG. 13, the cutting tool 22 is attached by tightening a fixing screw 27 on the tip surface of the final output shaft and sandwiching it between the outer flange 28 and the inner flange 29 in the plate thickness direction.

The upright portion 30a of the handle portion 30 is provided in an upright state from the vicinity of the joint portion between the gear housing 24 and the motor housing 25. The grip portion 30b extends rearward from the upper portion of the standing portion 30a. The handle portion 30 has a loop shape when viewed from the side. As shown in FIG. 5, a trigger type switch lever 31 is provided on the inner peripheral side of the handle portion 30. When the switch lever 31 is pulled with the fingertip of the hand holding the grip portion 30b, the electric motor 21 is activated and the cutting tool 22 is rotated. A lock-off lever 32 is provided above the switch lever 31. The switch lever 31 is locked in the normal state and cannot be pulled. By pushing down the lock-off lever 32 downward, the locked state of the switch lever 31 at the off position is released and the pulling operation becomes possible. This prevents an unintended and careless pulling operation of the switch lever 31.

An adapter accommodating portion 33 is provided on the left side portion of the upright portion 30a. The adapter accommodating portion 33 contains a communication adapter 33a for wireless communication. The communication adapter 33a enables short-range wireless communication between the portable cutting machine 1 and another wireless device. By short-range wireless communication, for example, the dust collector is started and stopped in conjunction with the start / stop operation of the portable cutting machine 1. With this wireless communication function, the worker can efficiently continue the cutting work while maintaining a clean working environment. The communication adapter 33a can be removed from the adapter accommodating portion 33. The removed communication adapter 33a can be diverted to another compatible power tool.

The rear side of the grip portion 30b is coupled to the upper surface of the battery mounting portion 40. A controller housing portion 35 is provided on the rear surface of the motor housing 25. The controller accommodating portion accommodates the controller 36 for controlling the operation of the electric motor 21. On the control board of the controller 36, a control circuit including a microcomputer that transmits a control signal based on the rotor position information detected by the sensor board, and a current of the electric motor 21 based on the control signal received from the control circuit are applied. It is equipped with a drive circuit composed of switching FETs, an auto stop circuit that cuts off the power supply to the electric motor 21 so as not to cause an over-discharge or an over-current state depending on the detection result of the state of the battery pack 41, and the like.

The battery mounting portion 40 is provided so as to project rearward from the upper portion of the controller accommodating portion 35. One battery pack 41 is attached to the lower surface side of the battery attachment portion 40. The battery pack 41 is a lithium-ion battery in which a plurality of battery cells are housed in a rectangular parallelepiped case, and a slide-mounted type is used. As shown in FIG. 2, the battery pack 41 can be attached by sliding it to the right with respect to the battery mounting portion 40, and can be removed by sliding it to the left. The removed battery pack 41 can be used repeatedly by charging it with a separately prepared charger. Further, the battery pack 41 can be removed from the battery mounting portion 40 and used as a power source for other power tools.

As shown in FIGS. 2, 3 and 5, a blower blowing nozzle 42 and a spindle lock lever 43 are provided near the front portion of the motor housing 25. The motor cooling air is exhausted from the blower blowing nozzle 42. By arranging the blower blowing nozzle 42 in the vicinity of the cooling fan built in the motor housing 25, it is possible to obtain exhaust with a sufficiently large air volume and wind speed. The cutting powder can be blown off by the exhaust of the motor cooling air blown from the blower blowing nozzle 42. The blower blowing nozzle 42 can be picked up with a fingertip and rotated to change the blowing direction of the motor cooling air. By pushing in the spindle lock lever 43, the rotation of the final shaft of the reduction gear train can be locked. By locking the final shaft, it is possible to facilitate the tightening and loosening work (replacement work of the cutting tool 22) of the fixing screw 27 at the time of replacing the cutting tool.

As shown in FIGS. 2 and 5, an illumination unit 44 is provided on the front portion of the gear housing 24 and on the left side portion of the fixed cover 23. Light from the front of the illumination unit 44, which uses an LED as a light source, is emitted toward the smear line guide unit 11 provided in the front portion of the base 10. When the electric motor 21 is started by pulling the switch lever 31, the lighting unit 44 lights up. The lighting unit 44 that stops the pulling operation of the switch lever 31 and stops the electric motor 21 is turned off. By illuminating the Sumi line guide unit 11 brightly with the light of the illumination unit 44, it is possible to efficiently perform the Sumi line alignment work in a dark place or the like.

As shown in FIGS. 2, 4 and 5, a hexagon wrench 45 is held in the battery mounting portion 40. The hexagon wrench 45 is removed from the battery mounting portion 40 and used for tightening and loosening the fixing screw 27. The hexagon wrench 45 used for the replacement work of the cutting tool 22 can be held in the battery mounting portion 40. Therefore, the replacement work can be performed quickly without the trouble of searching for the hexagon wrench 45 at the time of work.

The cutting machine main body 20 is supported so as to be tiltable to the left and right and swingable to the top and bottom with respect to the base 10. As shown in FIGS. 1 to 5, the angular plate 12 is arranged in a state of standing upward on the front portion of the upper surface of the base 10. A main body support bracket 13 is coupled to the rear surface of the angular plate 12. The main body support bracket 13 is supported so as to be tiltable to the left and right via the left and right tilt support shaft 14 shown in FIG. The front portion of the cutting machine main body 20 is supported by the angular plate 12 via the main body support bracket 13.

The front portion of the cutting machine main body 20 is supported so as to be tiltable to the left and right via the left and right tilting support shaft 14. The rear portion of the cutting machine main body 20 is supported on the upper surface of the base 10 via the rear support bracket 15. The rear support bracket 15 is supported so as to be tiltable to the left and right via the left and right tilt support shaft 16 shown in FIG. The left-right tilt support shaft 16 on the rear side is arranged coaxially with the left-right tilt support shaft 14 on the front side. The cutting machine main body 20 is supported so as to be tiltable to the left and right with respect to the base 10 via the front and rear tilting support shafts 14 and 16.

The left-right tilt position of the cutting machine main body 20 is fixed by tightening the fixing lever 12a on the front side and the pinching screw 15a on the rear side. By inclining the cutting machine main body 20 to the right, for example, by 45 °, so-called inclined cutting is performed in which the rotation axis of the cutting tool 22 intersects the upper surface of the material W to be cut at 45 °.

The main body support portion 20a provided on the front portion of the cutting machine main body 20 is supported by the main body support bracket 13 via the vertical swing support shaft 17. As shown in FIG. 9, the main body support portion 20a is integrally provided on the front portion of the left side wall portion 23a of the fixed cover 23. Therefore, the front portion of the cutting machine main body 20 is supported so as to be swingable up and down via the vertical swing support shaft 17. By changing the vertical swing position of the cutting machine main body 20, the amount of protrusion of the cutting tool 22 to the lower surface side of the base 10 can be changed. The amount of protrusion of the cutting tool 22 toward the lower surface side of the base 10 corresponds to the cutting depth of the cutting tool 22 with respect to the material W to be cut. A mechanism for adjusting the cutting depth is arranged between the base 10 and the rear side of the cutting machine main body 20.

As shown in FIGS. 4 and 6, the rear support bracket 15 is integrally provided with a depth guide 15b having an arc shape. The depth guide 15b is arranged so as to extend upward and diagonally forward along the left side portion of the fixed cover 23. A fixing screw (not visible in the figure) through which the depth guide 15b is inserted is screwed into the left wall portion 23a of the fixing cover 23. By operating the fixing lever 15c attached to the left end of the fixing screw in the tightening direction of the fixing screw, the vertical swing position of the cutting machine main body 20 with respect to the depth guide 15b is fixed. As a result, the cutting depth of the cutting tool 22 is fixed.

A dust box 50 for collecting dust is attached to the right side of the fixed cover 23. The dust box 50 can be removed from the fixed cover 23. FIGS. 6 to 8 show a state in which the dust box 50 is removed. By removing the dust box 50, the fixed cover 23 is exposed to the right side. The fixed cover 23 has a die-cast left side wall portion 23a and a transparent resin cover main body portion 23b.

The gear housing 24 is integrally molded on the left side of the left side wall portion 23a. The left wall portion 23a of the fixed cover 23 is formed so as to project in the radial direction from the right end of the gear housing 24. The cover main body portion 23b is coupled along the right side surface of the left side wall portion 23a. The cover main body 23b covers the periphery of the upper half-circumferential region of the cutting tool 22. The cover main body portion 23b is screwed to the left side wall portion 23a at a plurality of locations by fixing screws 23c.

A square tubular dust collecting duct 23d is integrally provided on the front portion of the cover main body 23b. The dust collecting duct 23d is opened vertically. The lower part of the dust collecting duct 23d reaches above the cutting portion C. A dust guide 23e is provided below the dust collecting duct 23d. The cutting dust blown up from the cutting portion C by the dust guide 23e is efficiently guided to the dust collecting duct 23d. A holding frame portion 23f for holding the front portion of the lighting portion 44 is integrally provided at the front portion of the dust collecting duct 23d. By being held by the holding frame portion 23f, the rattling of the lighting portion 44 is reduced. The cutting powder blown into the dust collecting duct 23d is collected in the dust box 50.

Details of the dust box 50 are shown in FIGS. 7, 8 and 10-12. The dust box 50 is coupled to the fixed cover 23 by the coupling mechanism 60. The dust box 50 has a left-right half-split structure in which the left-right half-split portions 51 and 52 are butted against each other. The left and right halves 51 and 52 are molded parts made of transparent resin, respectively. As shown in FIGS. 8 and 12, the left and right halves 51 and 52 are connected to each other at three points by three connecting screws 50d.

As shown in FIG. 13, the dust box 50 is mounted so as to be placed on the cover main body 23b of the fixed cover 23. For this reason, an arc-shaped mounting recess 50e is provided in the left half portion 51 of the dust box 50. The dust box 50 is attached in a state where the recess 50e is positioned along the upper surface of the cover main body 23b. An arc-shaped relief recess 50f is provided in the lower part of the dust box 50 to ensure visibility near the center of the cutting tool 22. The vicinity of the center of the cutting tool 22 is opened laterally through the relief recess 50f. This facilitates the replacement work of the cutting tool 22 with the dust box 50 attached.

A dust collecting port 50a to which the upper part of the dust collecting duct 23d is connected is provided at the front portion of the dust box 50. By connecting the dust collection port 50a to the dust collection duct 23d, the front side of the dust box 50 is mainly connected to the fixed cover 23 side.

As shown in FIGS. 7 and 8, the dust box 50 has a large-capacity dust collecting space inside. A large amount of cut powder that has flowed in through the dust collection port 50a can be accommodated. At the rear of the dust box 50, a discharge port 50b for discharging the contained cutting powder is provided. The discharge port 50b is opened and closed by the lid 53. As shown in FIGS. 11 and 12, the lid 53 is rotatably supported up and down via the opening / closing shaft 53a. The discharge port 50b is opened by rotating the lid 53 upward. By opening the discharge port 50b, the cutting powder contained in the dust box 50 can be discharged. The discharge port 50b is closed by rotating the lid 53 downward. A claw portion 53b for holding the closed state is provided in the lower portion of the lid 53. The closed state of the lid 53 is maintained by elastically hooking the claw portion 53b to the engaging recess 50c provided below the discharge port 50b. This prevents the lid 53 from being inadvertently opened due to vibration or the like.

The lid 53 is provided with a connection port 53c for connecting the dust collecting hose 54 as shown by the alternate long and short dash line in FIGS. 11 and 12. The connection port 53c is closed with a cap 53d. The cap 53d can be removed and the dust collector can be connected to the connection port 53c via the dust collecting hose 54. The dust collector can be started and stopped in conjunction with the portable cutting machine 1 by the wireless communication function described above. The cutting powder generated at the cutting site C is collected by the dust collector as it is without being accumulated in the dust box 50. By closing the connection port 53c with the cap 53d, a large amount of cutting powder can be temporarily stored in the dust box 50. The contained cutting powder is discharged from the discharge port 50b.

A cap holding portion 55 for holding the cap 53d removed from the connection port 53c is provided at the rear portion of the dust box 50. The engaging edge portion 55a is provided so as to project along the inner peripheral side of the cap holding portion 55. The cap 53d can be held by elastically hooking the engaging edge portion 55a. This prevents the removed cap 53d from being lost.

Details of the coupling mechanism 60 for coupling the dust box 50 to the cutting machine main body 20 are shown in FIGS. 7, 8, 13, and 14. The coupling mechanism 60 has one coupling shaft 61 and one shaft holding portion 62. The coupling shaft 61 has a first shaft portion 63 on the right side and a second shaft portion 64 on the left side. An axial force generating portion T is interposed between the first shaft portion 63 and the second shaft portion 64. An operation unit 65 for rotation operation is provided at the right end of the first shaft unit 63. A male screw portion 63a is provided on the left side of the first shaft portion 63.

The first shaft portion 63 is rotatably inserted into the insertion hole 52a of the right half-split portion 52 and the insertion hole 51a of the left half-split portion 51, respectively. The insertion hole 52a and the insertion hole 51a have substantially the same diameter and are arranged coaxially with each other. As shown in FIG. 13, the first shaft portion 63 is prevented from coming off from the insertion hole 52a by a retaining ring 66. The operation unit 65 has a disk-shaped base portion 65a and two finger hook portions 65b extending in the radial direction from the base portion 65a. The first shaft portion 63 can be rotated by hooking the fingertips on the two finger hook portions 65b. The operation unit 65 is housed in a circular storage recess 50g provided on the right side of the dust box 50 so as not to protrude.

A hexagonal shaft portion 64a is provided in a region substantially half of the second shaft portion 64 in the axial direction. A female screw portion 64b is provided on the right end surface of the hexagonal shaft portion 64a. The female screw portion 64b is provided coaxially with the second shaft portion 64. The male threaded portion 63a is screwed into the female threaded portion 64b, and the first shaft portion 63 and the second shaft portion 64 are coaxially coupled. The length of the coupling shaft 61 changes depending on the screwed state (tightening amount) of the male threaded portion 63a with respect to the female threaded portion 64b. As the length changes, the axial force of the coupling shaft 61 is generated or changed. Therefore, the screwed portion (screw tightening portion) of the male screw portion 63a with respect to the female screw portion 64b functions as the axial force generating portion T.

The hexagonal shaft portion 64a of the second shaft portion 64 is inserted into the hexagonal engaging hole portion 51b provided in the left half-split portion 51 of the dust box 50. The engaging hole portion 51b is formed on the inner peripheral side of the hexagonal cylindrical portion 51c integrally provided in the half-split portion 51. Therefore, the hexagonal shaft portion 64a is housed in the engaging hole portion 51b so that it can be displaced in the axial direction and cannot rotate around the axis. The insertion hole 51a is coaxially provided at the right end of the engagement hole 51b.

A cylindrical engaging shaft portion 64c is coaxially provided at the left end portion of the hexagonal shaft portion 64a. A disk-shaped hooking portion 64d is coaxially provided at the left end portion of the engaging shaft portion 64c. The second shaft portion 64 can be manufactured at low cost by lathe processing, tapping processing, or the like using one steel hexagonal shaft as a material.

The shaft holding portion 62 is provided on the upper portion of the left side wall portion 23a of the fixed cover 23. The shaft holding portion 62 has a U-shaped hooking groove portion 62a and a displacement regulating protrusion 62b. The hook groove portion 62a is provided in a direction of opening upward at the upper portion of the left side wall portion 23a. The hooking groove portion 62a is formed with a width in which the engaging shaft portion 64c of the second shaft portion 64 can be inserted and the hooking portion 64d cannot enter. Therefore, the hooking portion 64d is pressed against the left side surface of the left side wall portion 23a of the fixed cover 23 (the left side portion of the hooking groove portion 62a) by the axial force to the right of the coupling shaft 61.

According to the coupling mechanism 60 configured as described above, the dust box 50 is fixed to the cutting machine main body 20 by hooking the fingertip on the finger hook portion 65b of the operation portion 65 and rotating the first shaft portion 63 in the screw tightening direction. Will be done. When the first shaft portion 63 is rotated in the screw tightening direction, the male screw portion 63a is deeply tightened by the female screw portion 64b of the second shaft portion 64. As a result, the axial length of the coupling shaft 61 is shortened, and an axial force in the tensile direction is generated or strengthened.

The hooking portion 64d of the second shaft portion 64 is pressed against the left side surface of the left side wall portion 23a of the fixed cover 23 (the left side portion of the hooking groove portion 62a) by the axial force in the pulling direction of the coupling shaft 61. Further, the axial force of the coupling shaft 61 presses the operating portion 65 of the first shaft portion 63 against the bottom of the accommodating recess 50 g. As a result, at least the rear side of the dust box 50 is coupled to the cutting machine main body 20 side by the axial force of the coupling shaft 61. The front side of the dust box 50 is coupled to the cutting machine main body 20 side by inserting the dust collection port 50a into the upper part of the dust collection duct 23d of the fixed cover 23.

The dust box 50 can be removed by rotating the operation unit 65 in the screw loosening direction. By rotating the operation portion 65 in the screw loosening direction, the male screw portion 63a of the first shaft portion 63 is tightened shallowly with respect to the female screw portion 64b of the second shaft portion 64. As a result, the coupling shaft 61 becomes long. By lengthening the coupling shaft 61, the axial force is loosened (opened).

By relaxing the axial force of the coupling shaft 61, the pressing force of the operating portion 65 against the bottom of the accommodating recess 50 g and the pressing force of the hooking portion 64d against the left side wall portion 23a are reduced or eliminated. By releasing the pressing of the hooking portion 64d, the engaging shaft portion 64c can be displaced upward (diameterally) from the hooking groove portion 62a. As a result, the dust box 50 can be removed from the cutting machine main body 20 side while the coupling shaft 61 is separated from the shaft holding portion 62.

For example, one rotation of the operating portion 65 changes the length of the coupling shaft 61 by one pitch of the male screw portion 63a. As a result, the axial force of the coupling shaft 61 is significantly changed, and it is possible to switch between a state in which a coupling force sufficient to fix the dust box 50 is obtained and a state in which a looseness sufficient to remove the dust box 50 is obtained.

In the coupling mechanism 60 of the present embodiment, a displacement regulating protrusion 62b is provided to prevent the dust box 50 from being inadvertently removed even when the axial force of the coupling shaft 61 is loosened due to vibration or the like. ing. As shown in FIG. 9, the displacement regulating protrusion 62b is provided on the left side surface of the left side wall portion 23a. The displacement regulating protrusion 62b is provided so as to project above the hooking portion 64d pressed against the left side surface of the left side wall portion 23a. Therefore, the displacement regulating protrusion 62b regulates the upward displacement of the hooking portion 64d. As a result, the engagement shaft portion 64c is restricted from being detached from the hook groove portion 62a. Therefore, the disconnection of the coupling shaft 61 from the shaft holding portion 62 is restricted.

As shown in FIG. 15, the hooking portion 64d (second shaft portion 64) can be displaced to the left in the axial direction as shown by the white arrow A in the figure by relaxing the axial force of the coupling shaft 61. On the other hand, the displacement regulating protrusion 62b projects at a height H from the left side surface of the left side wall portion 23a of the fixed cover 23. Therefore, in order for the hooking portion 64d to be displaced upward, the condition is that the hooking portion 64d is displaced to the left by at least the displacement distance L (> height H) (loose axial force). Become. As shown by the white arrow B in the figure, the hooking portion 64d is allowed to be displaced upward on condition that the hooking portion 64d is displaced to the left of the displacement regulating protrusion 62b. As a result, the coupling shaft 61 is separated from the shaft holding portion 62, and the dust box 50 can be removed from the cutting machine main body 20 side.

From this, the coupling state of the dust box 50 by the coupling mechanism 60 is conditional on the looseness of the axial force by the coupling shaft 61 being larger than the set value (displacement distance L of the hooking portion 64d> height H of the displacement regulating protrusion 62b). Tolerated. If the looseness of the axial force is slight due to vibration or the like, the condition is not satisfied, and therefore the disconnection of the coupling shaft 61 from the shaft holding portion 62 is restricted. Therefore, careless removal of the dust box 50 is prevented.

According to the portable cutting machine 1 described above, by releasing or weakening the axial force of the coupling shaft 61, the pressing state of the dust box 50 against the cutting machine main body 20 by the hooking portion 64d is released. As a result, the coupling shaft 61 is displaced in the radial direction, and the hooking portion 64d is separated from the shaft holding portion 62. Therefore, the dust box 50 can be removed from the cutting machine main body 20. Therefore, the dust box 50 can be quickly and easily removed with a smaller amount of operation (axial force loosening operation) as compared with the conventional configuration in which the knob screw is rotated a plurality of times to remove the screw. Further, since it does not have a slide operating member like a conventional slide lever, cutting powder or the like does not get caught. As a result, the smooth operability of the coupling mechanism 60 can be maintained.

The operating portion 65 is provided at the other end of the coupling shaft 61 on the opposite side to the hooking portion 64d. By the rotation operation of the operation unit 65, the amount of tightening of the male screw portion 63a with respect to the female screw portion 64b in the axial force generating portion T changes. By loosening the tightening of the male screw portion 63a to the female screw portion 64b, the axial force of the coupling shaft 61 is released, and the coupling shaft 61 can be removed from the shaft holding portion 62. In this way, the coupling shaft 61 can be separated from the shaft holding portion 62 without removing the screw of the male screw portion 63a with respect to the female screw portion 64b.

The axial force generating portion T is formed by screwing a male screw portion 63a and a female screw portion 64b. Therefore, the axial force generating portion T can be provided so that the axial force can be reliably generated and released by a simple and inexpensive configuration.

The second shaft portion 64 having the hook portion 64d is non-rotatably engaged with the dust box 50 via the hexagonal shaft portion 64a. Therefore, the first shaft portion 63 having the operating portion 65 is rotatably supported by the dust box 50. By rotating the first shaft portion 63 via the operation portion 65, the screwing positions of the male screw portion 63a and the female screw portion 64b change. As a result, the axial length of the coupling shaft 61 changes, and an axial force is generated and released.

The second shaft portion 64 is non-rotatably engaged with the dust box 50 via the hexagonal shaft portion 64a. A part of the hexagonal shaft portion 64a in the axial direction has an engaging shaft portion 64c having a diameter smaller than that of the hook portion 64d. The engaging shaft portion 64c is brought into the hooking groove portion 62a of the shaft holding portion 62, and the hooking portion 64d is hooked on the shaft holding portion 62. With such a simple and inexpensive configuration, the hooking portion 64d is hooked on the shaft holding portion 62 without rotating.

The hooked state of the hooking portion 64d with respect to the shaft holding portion 62 is released by the displacement of the coupling shaft 61 in the radial direction (the direction intersecting the axis of the coupling shaft 61 at right angles). The radial displacement of the coupling shaft 61 is allowed only when the looseness of the axial force of the coupling shaft 61 is larger than the set value due to the displacement regulating protrusion 62b. This prevents the dust box 50 from being inadvertently removed when the axial force is loosened due to vibration or the like.

For example, it is assumed that the operation unit 65 rotates due to vibration or the like regardless of the rotation operation of the operation unit 65, and the axial force is loosened. Even in this case, if the looseness of the axial force is smaller than the set value, the radial displacement of the coupling shaft 61 is regulated by the displacement regulating protrusion 62b. As a result, the coupling shaft 61 is restricted from being detached from the shaft holding portion 62, and the dust box 50 is prevented from being inadvertently removed. When the looseness of the axial force of the coupling shaft 61 becomes larger than the setting by the operation of the user, the coupling shaft 61 can be displaced in the radial direction, and the dust box 50 can be removed.

The shaft holding portion 62 is formed on the cutting machine main body 20 side (left side wall portion 23a of the fixed cover 23). Therefore, the hooking portion 64d of the coupling shaft 61 is hooked on the shaft holding portion 62 on the cutting machine main body 20 side, and the dust box 50 is pressed against the cutting machine main body 20 side. The coupling shaft 61 is irremovably supported by the dust box 50. Therefore, the loss of the coupling shaft 61 is prevented, and it is not necessary to separately prepare the dust box 50 when it is attached. This makes it possible to improve the workability of attaching and detaching the dust box.

Various changes can be made to the embodiments described above. For example, as the axial force generating portion T for generating the axial force on the coupling shaft 61, a cam mechanism can be used instead of the configuration utilizing the screwed state of the male screw portion 63a and the female screw portion 64b.

Although not shown, a cam portion whose lift amount changes around the axis is interposed between the operation portion 65 and the accommodating recess 50 g. By rotating the operation unit 65, the cam unit is relatively displaced around the axis to displace the coupling shaft in the axial direction (dial cam type). In this case, the coupling shaft may be a single shaft member having an operating portion 65 for rotation operation at one end and a hooking portion 64d at the other end. In the case of the dial cam type, the axial force is generated or released without changing the length of one coupling shaft. One coupling shaft may be configured to be spring-biased to the left (axial force release side) by using, for example, a tension spring. By this spring urging force, the coupling shaft can be displaced in the axial direction to generate an axial force.

Further, although the configuration in which the axial force is generated or released by the rotational operation of the coupling shaft 61 of the operation unit 65 around the axis is illustrated, the axial force is generated or released by the tilting operation of the lever in the direction intersecting the axis of the coupling shaft 61. It can be configured to be open. In this case, the cam portion provided at the rotation base end portion of the lever can be pressed against the bottom portion of the accommodating recess 50 g to generate an axial force on the coupling shaft (cam lever type).

An example is shown in which the retaining ring 66 supports the coupling shaft 61 to the dust box 50 side so as not to be detached. However, by eliminating the retaining ring 66 and expanding the insertion holes 52a and 51a to a diameter that allows the hexagonal shaft portion 64a to pass through. It may be a separable configuration.

The coupling shaft 61 may be arranged oppositely to the left and right, the operation portion 65 may be arranged on the left side portion of the fixed cover 23, and the shaft holding portion 62 may be arranged on the dust box 50 side.

In the illustrated embodiment, the dust box 50 is pressed against the cutting machine main body 20 side by the axial force of the coupling shaft 61 to be coupled, but the displacement of the coupling shaft in the radial direction is simply regulated regardless of the axial force. The dust box can be combined with.

Although not shown, simultaneous codes are used for parts that can be diverted. In this case, one coupling shaft having an operating portion 65 on one end side and a hooking portion 64d on the other end portion and omitting the axial force generating portion T can be used. The hooking portion 64d is hooked on the shaft holding portion 62 in a state where the displacement of the coupling shaft in the axial direction is regulated by the displacement regulating protrusion 62b. As a result, the dust box 50 is coupled to the cutting machine main body 20 side.

The coupling shaft is moved in the axial direction by the displacement distance L so that the hooking portion 64d is displaced in the axial direction with respect to the displacement regulating protrusion 62b. As a result, the coupling shaft can be displaced in the radial direction. Therefore, the coupling shaft can be separated from the shaft holding portion 62. As a result, the hooked state of the hooking portion 64d with respect to the shaft holding portion 62 is released, and the dust box 50 can be removed from the cutting machine main body 20 side. For this reason, the dust box can be removed quickly and easily with a smaller amount of operation (axial displacement operation of the coupling shaft) as compared with the conventional configuration in which the knob screw is rotated a plurality of times to remove the screw. .. Further, since it does not have a slide operation unit as in the conventional case, the cutting powder does not get caught. As a result, smooth operability can be ensured.

Even when the coupling shaft is displaced in the axial direction due to vibration or the like, it is assumed that the amount of displacement is about rattling (looseness) smaller than the set value (height H of the displacement regulating protrusion 62b). In this case, the radial displacement of the coupling shaft is regulated by the displacement regulating protrusion 62b. Therefore, careless removal of the dust box is prevented. When the axial displacement of the coupling shaft becomes larger than the set value (height H of the displacement regulation protrusion 62b) by the user's operation, the coupling shaft is separated from the shaft holding portion 62 and the dust box 50 is removed. Can be done.

The dust box is removed by exemplifying a structure in which the hooking portion of the coupling shaft is displaced in the radial direction, but the dust box may be removed in a direction that intersects the axis of the coupling shaft, even if it is not in the radial direction. Preferably, it is easy to remove if the direction intersects the radial direction of the coupling shaft in the range of 0 to 30 °.

The portable cutting machine 1 can be similarly applied not only to a dust-proof circular saw using a saw blade as a cutting tool but also to a cutter using a diamond wheel as a cutting tool.

1 ... Portable cutting machine W ... Cut material C ... Cutting site 10 ... Base 11 ... Sumi wire guide part 12 ... Angular plate 12a ... Fixed lever 13 ... Main body support bracket 14 ... Left and right tilting support shaft 15 ... Rear support bracket 15a ... Picking screw, 15b ... Depth guide, 15c ... Fixed lever 16 ... Left / right tilting support shaft 17 ... Vertical swing support shaft 20 ... Cutting machine main body 20a ... Main body support 21 ... Electric motor J ... Motor axis 22 ... Cutting tool 23 ... Fixed Cover 23a ... Left wall, 23b ... Cover body, 23c ... Fixing screw, 23d ... Dust collection duct 23e ... Dust guide, 23f ... Holding frame 24 ... Gear housing 25 ... Motor housing 25a ... Intake port, 25b ... Fixing screw 26 ... Movable cover 26a ... Tension spring 27 ... Fixing screw 28 ... Outer flange 29 ... Inner flange 30 ... Handle part 30a ... Standing part, 30b ... Grip part 31 ... Switch lever 32 ... Lock-off lever 33 ... Adapter housing part 33a ... Communication Adapter 35 ... Controller housing 36 ... Controller 40 ... Battery mounting 41 ... Battery pack 42 ... Blower blowout nozzle 43 ... Spindle lock lever 44 ... Lighting unit 45 ... Hexagon wrench 50 ... Dust box 50a ... Dust collection port, 50b ... Discharge port, 50c ... Engagement recess, 50d ... Coupling screw 50e ... Mounting recess, 50f ... Relief recess, 50g ... Housing recess 51 ... Half split (left side)
51a ... Insertion hole, 51b ... Engagement hole, 51c ... Cylindrical part 52 ... Half-split part (right side)
52a ... Insertion hole 53 ... Lid 53a ... Opening and closing shaft, 53b ... Claw, 53c ... Connection port, 53d ... Cap 54 ... Dust collecting hose 55 ... Cap holding portion 55a ... Engaging edge 56 ... Arrow display (rotation of cutting tool 22) direction)
60 ... Coupling mechanism 61 ... Coupling shaft T ... Axial force generating part 62 ... Shaft holding part 62a ... Hooking groove part, 62b ... Displacement regulation protrusion 63 ... First shaft part 63a ... Male screw part 64 ... Second shaft part 64a ... Hexagon Shaft part, 64b ... Female thread part, 64c ... Engagement shaft part, 64d ... Hook part 65 ... Operation part 65a ... Base part, 65b ... Finger hook part 66 ... Retaining ring

Claims (11)

It ’s a portable cutting machine,
The cutting machine body that houses the electric motor and
The cutting tool rotated by the electric motor and
A dust box that collects the cutting powder generated by the cutting tool when cutting the material to be cut, and
It has a coupling mechanism that couples the dust box to the cutting machine body.
The coupling mechanism is
A shaft holding portion provided on any one of the dust box and the cutting machine main body,
A coupling shaft provided with a hooking portion and engaging with the shaft holding portion in the radial direction,
It has an axial force generating portion that generates an axial force on the coupling shaft and presses the dust box against the cutting machine main body by the hooking portion.
A portable cutting machine capable of removing the dust box from the cutting machine main body by removing the coupling shaft from the shaft holding portion in a direction intersecting the coupling shaft when the axial force of the coupling shaft is released. .. The portable cutting machine according to claim 1, having an operating portion at the other end of the coupling shaft opposite to the hooking portion, and rotating the operating portion around the axis of the coupling shaft. A portable cutting machine that releases the axial force. The portable cutting machine according to claim 2, wherein the operation unit has a disk-shaped base portion and two finger hook portions extending in radial directions from the base portion in opposite directions to each other. The axial force generating portion is a portable cutting machine configured by screwing a male screw portion and a female screw portion performed by rotating the operation portion. The portable cutting machine according to claim 3, wherein the coupling shaft has a first shaft portion having the operation portion and the male screw portion, and a second shaft portion having the female screw portion and the hook portion. For cutting machine. The portable cutting machine according to claim 4, wherein the second shaft portion is non-rotatably engaged with the dust box. The portable cutting machine according to claim 5, wherein the second shaft portion is non-rotatably engaged with the dust box via the hexagonal shaft portion, and the hook portion is engaged with a part of the hexagonal shaft portion in the axial direction. A portable cutting machine provided with an engaging shaft portion having a smaller diameter, allowing the engaging shaft portion to enter the shaft holding portion and hooking the hooking portion on the shaft holding portion. The portable cutting machine according to any one of claims 1 to 6, wherein a displacement of the coupling shaft in the radial direction is set in the shaft holding portion, and a looseness of the axial force of the coupling shaft is set. A portable cutting machine with a displacement-regulated protrusion that allows it to be large. The portable cutting machine according to any one of claims 1 to 7, wherein the shaft holding portion is formed on the cutting machine main body. The portable cutting machine according to any one of claims 1 to 8, wherein the coupling shaft is irremovably supported by the dust box. It ’s a portable cutting machine,
The cutting machine body that houses the electric motor and
The cutting tool rotated by the electric motor and
A dust box that collects the cutting powder generated by the cutting tool when cutting the material to be cut, and
It has a coupling mechanism that couples the dust box to the cutting machine body.
The coupling mechanism is
With the bond axis,
A hooking portion that presses the dust box against the cutting machine body due to an axial displacement of the coupling shaft, and a hooking portion.
A shaft holding portion formed so that the hooking portion can be disengaged by displacing the coupling shaft in a direction intersecting the coupling shaft.
A portable cutting machine having a displacement-regulating protrusion that allows a radial displacement of the coupling shaft on the shaft holding portion, provided that the axial displacement is larger than the set value. The portable cutting machine according to any one of claims 1 to 10.
A portable cutting machine in which the direction intersecting the coupling axis is the radial direction orthogonal to the coupling axis.

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