JP7487027B2 - Portable cutting machine with dust box - Google Patents

Description

This disclosure relates to a portable cutting machine with a dust box. Portable cutting machines include, for example, portable circular saws that are primarily used for cutting wood, or cutters that are primarily used for grinding stone.

Portable cutting machines have various ideas to prevent cutting dust generated by cutting from scattering around. Patent Documents 1 and 2 disclose portable cutting machines equipped with a dust box for collecting cutting dust. Cutting dust blown up from the cutting part is carried by the wind (dust collection wind) generated by the rotation of the cutting tool and collected in the dust box. The collected cutting dust is piled up in the dust box and disposed of. The dust box is provided with an air vent hole for venting air to suppress the rise in internal pressure. By suppressing the rise in internal pressure of the dust box, the dust collection wind flows in smoothly and dust collection efficiency is maintained.

Japanese Patent Application Laid-Open No. 4-235001 JP 2014-24177 A

In conventional dust boxes, in order to prevent cutting chips from leaking out through the vents for suppressing internal pressure, the vents are provided, for example, on the rear or bottom side of the dust box where the wind pressure of the dust-collecting air is relatively low. As a result, the effect of the vents in reducing internal pressure is insufficient. Therefore, it is necessary to improve the effect of the vents in reducing internal pressure while preventing the leakage of cutting chips.

According to one feature of the present disclosure, a portable cutting machine with a dust box includes a cutting machine body that houses an electric motor, and a cutting tool cover that covers a cutting tool rotated by the electric motor. The cutting machine also includes a dust box that is connected to the cutting tool cover and has a peripheral wall that runs along the periphery of the cutting tool to collect cutting dust. A ventilation opening is formed in the peripheral wall of the dust box. A filter member is attached to the ventilation opening.

Therefore, the dust-collecting wind is exhausted through the ventilation openings provided in the peripheral wall, an area where the wind force of the dust-collecting wind is relatively strong, and the increase in internal pressure within the dust box is efficiently suppressed. By attaching a filter member to the ventilation opening, cutting powder is prevented from leaking to the outside through the ventilation opening. This maintains the high dust-collecting efficiency of the dust box.

According to another feature of the present disclosure, the dust box has a cutting dust storage section that extends from the lower region of the ventilation opening to the rear region of the lower region and has a space for storing cutting dust. Therefore, cutting dust separated and removed from the dust collection air by the filter member attached to the ventilation opening falls and is stored in the cutting dust storage section. This maintains the dust collection efficiency of the dust box.

According to another feature of the present disclosure, a backflow prevention wall is provided upstream of the cuttings storage section to prevent the stored cuttings from flowing back. Therefore, the backflow prevention wall prevents the cuttings from flowing back, and the dust collection efficiency of the dust box is maintained.

According to another feature of the present disclosure, the filtering member is a pleated filter having many parallel folds. The filtering member is attached with the folds aligned along the thickness direction of the cutting tool. This allows the filtering member to be flexible in the radial direction of the cutting tool. This allows the filtering member to be deformed into an arc shape along the periphery of the cutting tool, allowing for efficient and compact arrangement.

According to another feature of the present disclosure, the blade cover has a movable cover that can be retracted and moved to a position that covers the lower area of the blade and a position that exposes the lower area of the blade. The dust box has a dust collection port located above the area cut by the blade, and an auxiliary dust collection port located behind the dust collection port and in the movable area of the movable cover. Therefore, cutting dust that accumulates between the blade cover and the movable cover behind the dust collection port is collected in the dust box through the auxiliary dust collection port. This improves the dust collection efficiency of the dust box.

According to another feature of the present disclosure, the dust box is provided with a guide portion downstream of the dust collection port that extends the flow of dust collection air generated by the rotation of the cutting tool toward the ventilation opening. Therefore, the dust collection air is efficiently exhausted through the ventilation opening. This effectively suppresses the rise in internal pressure within the dust box.

According to another feature of the present disclosure, the peripheral wall of the dust box is arc-shaped along the outer periphery of the cutting tool, and the filter member is arranged in an arc shape along the peripheral wall. Therefore, cutting dust is efficiently blocked while the dust-collecting air is exhausted to the outside through the ventilation opening.

According to another feature of the present disclosure, the cutting tool has a case body that houses a filter member, and a ventilation opening is formed on the upper surface of the case body. Therefore, the dust-collecting air is exhausted from the ventilation opening in a state where cutting dust is removed by the filter member contained in the case body.

According to another feature of the present disclosure, the dust box is provided with an impact mechanism for applying an impact to the filter member. Therefore, the impact is applied to the filter member, preventing clogging. This maintains the ventilation efficiency of the filter member, and maintains the effect of suppressing an increase in internal pressure within the dust box.

According to another feature of the present disclosure, a filter member is attached to the dust box across the top of the peripheral wall. Therefore, the dust-collecting wind is efficiently exhausted through the top of the peripheral wall where the dust-collecting wind is blown strongest and has the highest wind pressure. This effectively suppresses an increase in the internal pressure of the dust box.

This is an overall perspective view of a portable cutting machine with a dust box, as seen from the front right side. This is an overall perspective view of a portable cutting machine with a dust box, as seen from the front left. This is an overall perspective view of the portable cutting machine with a dust box, as seen from the rear diagonally left side. FIG. 2 is a right side view of the portable cutting machine with a dust box. FIG. 2 is a top view of the portable cutting machine with a dust box. FIG. 2 is a front view of the portable cutting machine with a dust box. FIG. 2 is a rear view of the portable cutting machine with a dust box. FIG. 2 is a left side view of the portable cutting machine with a dust box. Fig. 7 is a cross-sectional view taken along line IX-IX in Fig. 6. In this figure, the dust box is shown in vertical section. Fig. 2 is an overall perspective view of the dust box, as viewed diagonally from the front left side. FIG. FIG. FIG. 2 is a right side view of the portable cutting machine with a dust box, in which the dust box is shown in vertical section, and in which the waste cover is shown in an open position. This is an overall perspective view of the portable cutting machine with a dust box, as seen from the rear left side, with the waste lid open.

Next, an embodiment will be described with reference to the attached drawings. As shown in Figs. 1 to 8, in this embodiment, a handheld cutting machine also called a dustproof circular saw is illustrated as an example of a portable cutting machine with a dust box (hereinafter simply referred to as "portable cutting machine 1"). This portable cutting machine 1 is used for cutting siding, masonry boards, and the like, for example, at a construction site of a house. The user is positioned behind the portable cutting machine 1. The cutting process of the workpiece W progresses as the user moves the portable cutting machine 1 forward by performing a movement operation. In the following description, the direction in which cutting progresses for each of the members and configurations is referred to as the front side, and the side where the user is located is referred to as the rear side. The left and right directions are based on the user.

The portable cutting machine 1 comprises a rectangular flat base 10 that is brought into contact with the top surface of the workpiece W, and a cutting machine body 20 supported on the top side of the base 10. A dust box 50 for collecting dust is attached to the right side of the cutting machine body 20. The cutting machine body 20 comprises a circular cutting tool 22, called a chip saw, that is rotated by an electric motor 21. The periphery of the upper side of the cutting tool 22 is covered by a cutting tool cover 23. The lower side of the cutting tool 22 protrudes from the underside of the base 10. The lower side of the cutting tool 22 is covered by a movable cover 26 that can be opened and closed. The movable cover 26 is provided so as to be able to appear and disappear from the cutting tool cover 23 so as to move between a position covering the lower region of the cutting tool 22 and a position exposing it.

As shown in Figures 4, 9, and 13, the movable cover 26 is biased in the closing direction by the tension spring 26a. When the portable cutting machine 1 is moved forward with the movable cover 26 in contact with the workpiece W, the movable cover 26 rotates relatively clockwise in Figure 4 and opens. The movable cover 26 opens against the tension spring 26a, exposing the cutting tool 22. The exposed part of the cutting tool 22 cuts into the workpiece W to perform the cutting process.

The cutting tool 22 rotates counterclockwise in FIG. 4. The direction of rotation of the cutting tool 22 is indicated by an arrow 50f displayed on the right side of the dust box 50 in FIGS. 1 and 4. The front end of the exposed part of the cutting tool 22 protruding from the underside of the base 10 cuts into the workpiece W to perform the cutting process. The part where the front end of the cutting tool 22 cuts into the workpiece W becomes the cutting area C. Cutting powder is blown upward from the cutting area C. The blown cutting powder is collected in the dust box 50. Details of the dust box 50 will be described later.

The motor housing 25 is connected to the left side of the cutting tool cover 23 via the gear housing 24. The gear housing 24 and the cutting tool cover 23 are integrated with screws. Although not shown in the figure, the gear housing 24 is equipped with a gear train for reducing the rotational output of the electric motor 21. The gear train uses a two-stage reduction gear train of spur gears.

The motor housing 25 is screwed to the left end of the gear housing 24. The electric motor 21 is housed inside the motor housing 25. A DC brushless motor is used for the electric motor 21. The motor axis (axis of the output shaft) J of the electric motor 21 extends in the left-right direction. The left end face of the motor housing 25 is provided with multiple air intakes 25a for introducing outside air for cooling the motor.

The rotational output of the electric motor 21 is reduced by a reduction gear train and output to the spindle 27 (shown only in Figs. 9 and 13). The spindle 27 protrudes into the cutting tool cover 23. The cutting tool 22 is attached to the protruding portion of the spindle 27. The cutting tool 22 is not shown in Fig. 1. The cutting tool 22 is attached by being sandwiched between the outer flange 28 and the inner flange 29 in the plate thickness direction with a fixing screw 27a fastened to the tip surface of the spindle 27.

The handle section 30 has a standing portion 30a that stands upward near the joint between the gear housing 24 and the motor housing 25. The grip section 30b extends rearward from the top of the standing portion 30a. The handle section 30 has a loop shape in a side view. As shown in FIG. 8, a switch lever 31 for starting the electric motor 21 is provided on the inner periphery of the handle section 30. When the switch lever 31 is pulled with the fingertips of the hand holding the grip section 30b, the electric motor 21 starts and the cutting tool 22 rotates. A lock-off button 32 is provided above the switch lever 31. The switch lever 31 is normally locked and cannot be pulled. By pushing the lock-off button 32 to the left or right, the switch lever 31 is released from the locked state in the off position and can be pulled. This prevents the switch lever 31 from being pulled unintentionally or carelessly.

As shown in Figures 2, 3, and 8, an adapter storage section 33 is provided on the left side of the standing section 30a. A communication adapter 34 for wireless communication is installed inside the adapter storage section 33. The communication adapter 34 performs short-distance wireless communication between the portable cutting machine 1 and other wireless devices. By short-distance wireless communication, for example, a dust collector is started and stopped in conjunction with the start and stop operation of the portable cutting machine 1. This wireless communication function allows the operator to efficiently continue cutting work while maintaining a clean work environment. The communication adapter 34 can be removed from the adapter storage section 33. The removed communication adapter 34 can be used for other compatible power tools.

The rear side of the grip portion 30b is connected to the upper surface of the battery attachment portion 40. A controller housing portion 35 is provided on the rear surface of the motor housing 25. The controller housing portion 35 houses a controller 36 for controlling the operation of the electric motor 21. The control board of the controller 36 is equipped with a control circuit made of a microcomputer that transmits a control signal based on rotor position information detected by the sensor board of the electric motor 21. The control board of the controller 36 is also equipped with a drive circuit made of FETs that switches the current of the electric motor 21 based on the control signal received from the control circuit. The control board of the controller 36 is also equipped with an auto-stop circuit that cuts off the power supply to the electric motor 21 according to the detection result of the state of the battery pack 41 to prevent over-discharge or over-current.

The battery attachment section 40 is provided so as to protrude rearward from the top of the controller housing section 35. One battery pack 41 is attached to the underside of the battery attachment section 40. The battery pack 41 is a lithium ion battery that contains multiple battery cells in a rectangular parallelepiped case, and is of a slide-attached type. As shown in Figures 3, 5, and 7, the battery pack 41 can be attached by sliding it to the right relative to the battery attachment section 40, and removed by sliding it to the left. The removed battery pack 41 can be used repeatedly by charging it with a separately prepared charger. The battery pack 41 can also be removed from the battery attachment section 40 and used as a power source for other power tools.

As shown in FIG. 2, a blower nozzle 42 and a spindle lock lever 43 are provided near the front of the motor housing 25. Motor cooling air is exhausted from the blower nozzle 42. By arranging the blower nozzle 42 near the cooling fan built into the motor housing 25, it is possible to obtain a sufficiently large exhaust air volume and speed. Cutting powder can be blown away by the exhaust of motor cooling air blown out from the blower nozzle 42. The rotation of the spindle 27 can be locked by pushing in the spindle lock lever 43. Locking the spindle 27 facilitates the tightening and loosening of the fixing screw 27a when replacing the cutting tool (replacement of the cutting tool 22).

As shown in Figures 2 and 6, an illumination unit 44 is provided at the front of the gear housing 24, which is in front of the cutting tool cover 23. Light from an LED light source is emitted from the front of the illumination unit 44 toward the fillet line guide unit 11 provided at the front of the base 10. When the switch lever 31 is pulled to start the electric motor 21, the illumination unit 44 is turned on. When the switch lever 31 is no longer pulled to stop the electric motor 21, the illumination unit 44 is turned off. The fillet line guide unit 11 is brightly illuminated by the light from the illumination unit 44, so that fillet line alignment work can be performed efficiently in dark places, etc.

The upper part of the motor housing 25 is provided with legs 37 for touching the ground when the portable cutting machine 1 is in an inverted position with the underside of the base 10 facing upwards, and the legs 37, the upper part of the handle part 30, and the front corners of the base 10 are in contact with the ground, allowing the portable cutting machine 1 to be placed in a stable inverted position. This allows the user to temporarily let go of the portable cutting machine 1 during a break in processing work and place it in a stable position.

As shown in Figures 2, 3, 5 and 7, a hexagonal wrench holder 45 is provided on the top surface of the battery attachment section 40. For example, a hexagonal wrench can be held in the hexagonal wrench holder 45. The hexagonal wrench holder 45 is composed of a section that elastically clamps and holds the body of the hexagonal wrench, and a holding hole into which the tip is inserted and held. The hexagonal wrench is not shown in the figures. By tightening the fixing screw 27a that secures the cutting tool 22 and holding the hexagonal wrench used for loosening work in the hexagonal wrench holder 45, replacement work can be performed quickly without the trouble of searching for the hexagonal wrench when working.

The cutting machine body 20 is supported on the base 10 via the front support part 2 and the rear support part 3 so that it can tilt left and right and swing up and down. The front support part 2 is provided on the front part of the upper surface of the base 10, and the rear support part 3 is provided on the rear part of the upper surface. As shown in Figures 1, 2, 5, and 6, the front angular plate 12 of the front support part 2 is arranged in an upwardly standing state on the front part of the upper surface of the base 10. A front support bracket 13 is connected to the rear surface of the front angular plate 12. The front support bracket 13 is supported so that it can tilt left and right via the left and right tilting support shaft 14 shown in Figures 1 and 6. The front part of the cutting machine body 20 is supported on the front angular plate 12 via the front support bracket 13.

The front of the cutting machine body 20 is supported so that it can tilt left and right via the left and right tilting support shaft 14. As shown in Figures 4, 5, and 7, the rear of the cutting machine body 20 is supported on the base 10 via the rear support part 3. A rear angular plate 18 is provided on the rear part of the upper surface of the base 10 in an upwardly standing state. A rear support bracket 15 is supported on the front surface of the rear angular plate 18. The rear support bracket 15 is supported so that it can tilt left and right via the left and right tilting support shaft 16. The left and right tilting support shaft 16 on the rear side is arranged coaxially with the left and right tilting support shaft 14 on the front side. The cutting machine body 20 is supported so that it can tilt left and right relative to the base 10 via the front and rear left and right tilting support shafts 14, 16.

The left and right tilting positions of the cutting machine body 20 are fixed by tightening the front fixing lever 12a and the rear thumbscrew 15a. By tilting the cutting machine body 20, for example, 45° to the right, a so-called oblique cut is made in which the axis of rotation of the cutting tool 22 intersects with the top surface of the workpiece W at 45°.

The body support 20a provided at the front of the cutting machine body 20 is supported by the front support bracket 13 via the vertical swing support shaft 17. As shown in Figs. 5 and 8, the body support 20a is provided in a state in which it protrudes forward from the front of the gear housing 24. The cutting machine body 20 is supported so as to be able to swing up and down via the vertical swing support shaft 17. By changing the vertical swing position of the cutting machine body 20, the amount of protrusion of the cutting tool 22 toward the underside of the base 10 can be changed. The amount of protrusion of the cutting tool 22 toward the underside of the base 10 corresponds to the cutting depth of the cutting tool 22 into the workpiece W. A mechanism for adjusting the cutting depth is disposed between the base 10 and the rear side of the cutting machine body 20.

As shown in Figures 5 and 7, the rear support bracket 15 supports an arc-shaped depth guide 15b via a swinging support shaft 15e so that it can swing up and down. The depth guide 15b is arranged to extend upward and diagonally forward along the left side of the gear housing 24. A fixing screw 15d is inserted through the depth guide 15b and is screwed into the left wall of the gear housing 24. The vertical swing position of the cutting machine body 20 relative to the depth guide 15b is fixed by operating the fixing lever 15c attached to the fixing screw 15d in the direction in which the fixing screw 15d is tightened. This fixes the cutting depth of the cutting tool 22.

A dust box 50 for collecting dust is provided on the right side of the cutting tool cover 23. The dust box 50 can be removed from the cutting tool cover 23 and the gear housing 24. Figure 10 shows the removed dust box 50 on its own. The dust box 50 is a synthetic resin box with a large-capacity dust collection space inside, and is attached to cover the top, right side, and rear of the cutting tool cover 23.

A thumb screw 51 is provided on the right side 50g of the dust box 50. By rotating the thumb screw 51, the attachment state of the dust box 50 to the gear housing 24 can be locked or unlocked. A connecting shaft 52 is attached to the thumb screw 51. The connecting shaft 52 extends long to the left. As shown in FIG. 10, a male threaded portion 52a provided on the left end of the connecting shaft 52 protrudes from the left side of the dust box 50. A female threaded portion 24a (see FIGS. 9 and 13) is formed on the gear housing 24. By rotating the thumb screw 51, the connecting shaft 52 is rotated around its axis, and the male threaded portion 52a is screwed into the female threaded portion 24a and screwed to the gear housing 24. The connecting shaft 52 is engaged with the gear housing 24, and the dust box 50 is fixed to the gear housing 24. The dust box 50 can be removed from the gear housing 24 (tool cover 23) by rotating the thumbscrew 51 to disengage the connecting shaft 52.

As shown in Figures 4 and 9, a square cylindrical dust collection duct 23a is integrally provided at the front of the cutting tool cover 23. The dust collection duct 23a is open at the top and bottom. The lower part of the dust collection duct 23a reaches above the cutting part C. The cutting dust is blown up into the dust collection duct 23a by the dust collection wind generated by the cutting tool 22 rotating counterclockwise in Figure 4. The cutting dust blown into the dust collection duct 23a is collected in the dust box 50.

A dust collection port 53 is provided at the front of the dust box 50, to which the upper part of the dust collection duct 23a is connected. By connecting the dust collection port 53 to the dust collection duct 23a, mainly the front side of the dust box 50 is connected to the cutting tool cover 23 side. The inside of the dust box 50 has a large-capacity dust collection space. It is designed to accommodate a large amount of cutting powder that flows in through the dust collection port 53.

An auxiliary dust collection port 59 is provided behind the dust collection port 53. The auxiliary dust collection port 59 is arranged in the movable area of the movable cover 26. The cutting process is performed with the movable cover 26 in an open or fully open state. The movable cover 26 enters between the peripheral wall portion of the cutting tool cover 23 and the cutting tool 22 and is opened or fully opened. For this reason, during cutting, the cutting dust blown up from the dust collection port 53 to the rear is likely to accumulate on the upper surface (outer surface) of the movable cover 26 that has entered the inner peripheral side of the cutting tool cover 23. In this way, the cutting dust accumulated between the cutting tool cover 23 and the movable cover 26 behind the dust collection port 53 is collected in the dust box 50 through the auxiliary dust collection port 59. The cutting dust accumulated on the movable cover 26 is blown up to the auxiliary dust collection port 59 by the dust collection wind generated by the rotation of the cutting tool 22. In addition, the cutting dust blown up into the auxiliary dust collection port 59 is collected in the dust box 50 by the suction action of the dust collection airflow (arrow (A)) flowing in from the dust collection port 53. This further improves the dust collection efficiency of the dust box 50.

A guide portion 50d is provided at the downstream end of the auxiliary dust collection port 59 to guide the incoming dust collection air toward the ventilation opening 54. The dust collection air that flows in from the dust collection port 53 and the auxiliary dust collection port 59 is guided by the guide portion 50d toward the ventilation opening 54. The flow of the dust collection air that flows in through the dust collection port 53 and the auxiliary dust collection port 59 is indicated by the arrow (A) in FIG. 9.

The upper part of the dust box 50 is provided with an arc-shaped peripheral wall 50a that follows the periphery of the cutting tool 22. The peripheral wall 50a corresponds to the top plate of the dust box 50, and is provided in the area extending from the front to the rear. The peripheral wall 50a is provided with a rectangular ventilation opening 54. The ventilation opening 54 is provided in a long area that spans from the front to the rear, with the top part (highest part) of the peripheral wall 50a as the boundary. The ventilation opening 54 is provided with a large width in the left-right width direction of the peripheral wall 50a.

The flow of dust-collecting wind indicated by the arrow (A) in FIG. 9 is blown against the ventilation opening 54. The ventilation opening 54 is provided in an area where the wind pressure of the dust-collecting wind flowing in from the dust collection port 53 is the highest. Therefore, most of the dust-collecting wind is exhausted directly to the outside through the ventilation opening 54. This effectively suppresses the rise in internal pressure of the dust box 50.

The ventilation opening 54 is covered with a filter member 55 for removing cutting powder. The filter member 55 is shown alone in Figure 11. The filter member 55 is a so-called pleated filter, and has a bellows shape with repeated mountain and valley folds at numerous folds 55a. The filter member 55 has a roughly rectangular parallelepiped shape overall. The filter members 55 are attached with the numerous folds 55a oriented along the left-right direction (the plate thickness direction of the cutting tool 22) and arranged parallel to each other in the front-rear direction. This gives the filter member 55 flexibility to be bent up and down (in the radial direction of the cutting tool 22).

The filter member 55 is housed in a case body 56. As shown in Figures 9 and 10, the case body 56 is curved in a gentle arc along the peripheral wall 50a of the dust box 50 (the cutting edge of the cutting tool 22) in a side view. The housed filter member 55 is also curved in a gentle arc following the curve of the case body 56.

Figure 12 shows the filter member 55 alone housed in the case body 56. Figure 12 shows the filter member 55 as viewed from the bottom side (inside the dust box 50). A rectangular, large opening window 56a is provided on the bottom surface of the case body 56. Through the window 56a, almost the entire bottom surface of the filter member 55 faces the inside of the dust box 50 via the ventilation opening 54. The filter member 55 is glued to the case body 56 and held in place to prevent it from falling off.

As shown in FIG. 10, a number of ventilation holes 56b are formed on the upper surface (first wall 56e) of the case body 56. The multiple ventilation holes 56b are connected to the inside of the dust box 50 via the window portion 56a and the ventilation opening 54. A pair of left and right arms 56c are provided at the front of the case body 56. A mountain-shaped connecting protrusion 50b is provided on the front upper surface of the peripheral wall 50a of the dust box 50. The connecting protrusion 50b is positioned between the left and right arms 56c, and one connecting shaft 56d is press-fitted into the three. This allows the front of the case body 56 to be connected to the peripheral wall 50a of the dust box 50 without any rattling.

A cylindrical body 56g is integrally provided at the rear of the case body 56, extending in the left-right width direction. The cylindrical body 56g is screwed to the rear of the peripheral wall 50a of the dust box 50 with a single fixing screw 56h. The rear of the case body 56 is connected to the dust box 50 side by screwing with the fixing screw 56h. The case body 56 is provided with left and right second walls 56f that are perpendicular to the first wall 56e. The second walls 56f correspond to the side walls of the case body 56.

The impact mechanism 60 is disposed on the second wall 56f on the left side. In this embodiment, a long strip-shaped spring plate (leaf spring) is exemplified as the impact mechanism 60. The rear part (second end) of the impact mechanism 60 is screwed to the second wall 56f with a fixing screw 61. The front part (first end) of the impact mechanism 60 is bent toward the side away from the second wall 56f, and a finger hook 60a (operating member) is provided. The user can hook a finger on the finger hook 60a and elastically deform the impact mechanism 60 in a direction away from the second wall 56f (rotate in the lifting direction), and then release the fingertip to flip it. The bounced impact mechanism 60 rotates due to its elastic force and elastically collides with the second wall 56f. This applies an impact to the case body 56.

In this embodiment, one leaf spring (impact mechanism 60) serves as both the operating member, the elastic member, and the striking member. When an impact is applied to the case body 56, an impact is applied to the filter member 55 itself, and cutting powder that has been removed from the dust-collecting air and adhered to the filter member 55 is shaken off. This clears clogging of the filter member 55. In addition, by applying an operating force to the finger hook portion 60a, which serves as the operating member at the first end, the striking member, which is an elastic member, deforms with the second end (the portion screwed by the fixing screw 61) as a fulcrum. Therefore, the impact mechanism 60 can be elastically deformed with a relatively small force by utilizing the principle of leverage.

The impact mechanism 60 is provided on the second wall 56f on the left side of the case body 56. The impact mechanism 60 has an elongated shape that fits along the handle portion 30, and the finger hook 60a at the front is disposed diagonally forward and to the right of the switch lever 31 of the handle portion 30. For this reason, as shown in Figures 2, 3, 5, and 14, the finger hook 60a of the impact mechanism 60 is disposed at a position where it can be easily played and operated by stretching out the fingertips of the hand holding the grip portion 30b. This ensures good operability of the impact mechanism 60.

As shown by the arrow (A) in FIG. 9, the cutting dust is blown onto the filter member 55 by the dust collection wind. The cutting dust is removed by the filter member 55, and clean air is exhausted from the ventilation hole 56b. The cutting dust removed from the dust collection wind by the filter member 55 and the cutting dust shaken off by the impact mechanism 60 fall downward as shown by the arrows (B) and (C) in FIG. 9. A cutting dust storage section 50c is provided at the bottom of the dust box 50. A waste storage section 50e is provided behind the cutting dust storage section 50c. A backflow prevention wall 50r is provided in front (upstream side) of the cutting dust storage section 50c so as to protrude upward. The backflow prevention wall 50r prevents the cutting dust stored in the cutting dust storage section 50c and the waste storage section 50e from flowing back forward. The front side of the backflow prevention wall 50r functions as the guide section 50d described above.

At the rear of the dust box 50, a waste port 65 is provided for discharging the stored cutting dust. The waste port 65 is opened and closed by a lid 66. The lid 66 is supported so as to be rotatable up and down via an opening and closing shaft 67. The waste port 65 is opened by rotating the lid 66 upward. By opening the waste port 65, the cutting dust collected in the dust box 50 can be disposed of. The waste port 65 is closed by rotating the lid 66 downward. At the bottom of the lid 66, a claw portion 66a is provided for maintaining the closed state. The claw portion 66a is elastically hooked onto an engagement recess 65a provided below the waste port 65, thereby maintaining the closed state of the lid 66. This prevents the lid 66 from being inadvertently opened due to an impact or the like.

The lid 66 is provided with a cylindrical connection port 68 for connecting a dust collection hose. The connection port 68 is closed with a cap 69. By removing the cap 69, a dust collector can be connected to the connection port 68 via a dust collection hose. The dust collector can be started and stopped in conjunction with the portable cutting machine 1 by the wireless communication function described above. Cutting dust generated at the cutting site C is not accumulated in the dust box 50, but is collected by the dust collector as it is. By closing the connection port 68 with the cap 69, a large amount of cutting dust can be temporarily collected in the dust box 50, mainly in the cutting dust storage section 50c and the waste storage section 50e. The collected cutting dust is discarded from the waste port 65.

According to the portable cutting machine 1 described above, the dust box 50 has a peripheral wall 50a that runs along the periphery of the cutting tool 22. A ventilation opening 54 is formed at the top of the peripheral wall 50a, in the area where the wind pressure of the dust collection wind is highest. This efficiently suppresses the rise in the internal pressure of the dust box 50. In addition, a filter member 55 is attached to the ventilation opening 54. This ensures that cutting powder is removed from the dust collection wind, and the air is exhausted from the ventilation opening 56b in a clean state. This also maintains the high dust collection efficiency of the dust box 50.

In addition, the impact mechanism 60 applies an impact to the filter member 55 via the case body 56. This prevents clogging of the filter member 55. Preventing clogging of the filter member 55 suppresses an increase in the airflow resistance of the filter member 55. This suppresses an increase in the airflow resistance of the ventilation opening 54 and the ventilation hole 56b, and suppresses an increase in the internal pressure of the dust box 50. By suppressing an increase in internal pressure, the flow of dust collection air containing cutting powder into the dust box 50 is smooth, maintaining high dust collection efficiency.

The dust box 50 further has a cutting dust storage section 50c and a waste storage section 50e that extend from the lower region of the ventilation opening 54 to the rear region of the lower region and have a space for storing cutting dust. The dust collection efficiency of the dust box 50 is maintained by storing cutting dust that has been separated and removed from the dust collection wind by the filter member 55 and fallen in the cutting dust storage section 50c and the waste storage section 50e.

In addition, according to the illustrated portable cutting machine 1, a backflow prevention wall 50r is provided upstream of the cutting powder storage section 50c to prevent the stored cutting powder from flowing back. The backflow prevention wall 50r prevents the cutting powder from flowing back, maintaining the storage function of the cutting powder storage section 50c and thus the dust collection efficiency of the dust box 50.

The filter member 55 is a pleated filter having many parallel folds 55a. The filter member 55 is attached so that the folds 55a are aligned along the thickness direction (left-right direction) of the cutting tool 22. This allows the filter member 55 to be flexible in the radial direction of the cutting tool 22. This allows the filter member 55 to be curved in an arc shape around the cutting tool 22, allowing for efficient and compact arrangement.

An auxiliary dust collection port 59 is provided behind the dust collection port 53 of the dust box 50. Cutting dust blown backward from the dust collection duct 23a or cutting dust leaking backward from the dust collection port 53 tends to accumulate on the upper surface (outer peripheral surface) of the movable cover 26 that is fully opened during cutting processing. In this way, cutting dust accumulated between the cutting tool cover 23 and the movable cover 26 behind the dust collection port 53 is collected into the dust box 50 via the auxiliary dust collection port 59. This further improves the dust collection efficiency of the dust box 50.

The above-described embodiment can be modified in various ways. For example, the ventilation opening 54 is illustrated as being provided in a region that spans the front and rear of the zenith (highest part) of the peripheral wall 50a, but it may also be located in a region that includes the zenith and is shifted forward, or in a region that includes the zenith and is shifted backward.

The ventilation openings may be located in the front or rear area outside the top of the peripheral wall 50a, and may be located in multiple separate locations instead of just one. A filter member held by the case body may be placed around the multiple ventilation openings.

The configuration in which the front part of the case body 56 that holds the filter member 55 is connected to the peripheral wall 50a of the dust box 50 via the connecting shaft 56d has been exemplified, but it may also be configured to be connected by screwing in the same manner as the rear side. Also, the case body 56 may be configured to be connected to the peripheral wall 50a by adhesive.

The filter member 55 shown in the example is a pleated filter having a bellows shape with multiple folds 55a, but a sheet-type filter may also be used.

The location of the impact mechanism 60 can be changed, for example, to the second wall 56f or the first wall 56e on the right side. The impact mechanism 60 may also be placed on the right side 50g of the dust box or on the cutting machine body 20 side.

The impact mechanism 60 may be omitted.

The portable cutting machine with dust box 1 can be used not only for dustproof circular saws that use circular saw blades such as tipped saws as cutting tools, but also for cutters that use diamond wheels as cutting tools.

1...Portable cutting machine 2...Front support part 3...Rear support part W...Material to be cut C...Cutting part 10...Base 11...Slit line guide part 12...Front angular plate, 12a...Fixed lever 13...Front support bracket 14...Right and left tilting support shaft 15...Rear support bracket 15a...Thumb screw, 15b...Depth guide, 15c...Fixed lever, 15d...Fixed screw 15e...Swinging support shaft 16...Right and left tilting support shaft 17...Up and down swing Support shaft 18...rear angular plate 20...cutting machine body, 20a...body support section 21...electric motor J...motor shaft 22...cutting tool 23...cutting tool cover, 23a...dust collection duct 24...gear housing, 24a...female thread section 25...motor housing, 25a...air intake 26...movable cover, 26a...tension spring 27...spindle, 27a...fixing screw 28...outer flange 29...inner flange 30...handle section 30a...standing section, 30b...grip section 31...switch lever 32...lock-off button 33...adapter housing section 34...communication adapter 35...controller housing section 36...controller 37...legs 40...battery attachment section 41...battery pack 42...blower nozzle 43...spindle lock lever 44...lighting section 45...hexagonal wrench holder section 50...dust box 50a...periphery Wall, 50b...connecting protrusion, 50c...cutting powder storage section, 50d...guide section 50e...waste storage section, 50f...arrow marking, 50g...right side, 50r...backflow prevention wall 51...knob screw 52...connecting shaft, 52a...male threaded section 53...dust collection port 54...ventilation opening 55...filter member (filter), 55a...fold 56...case body 56a...window section, 56b...ventilation port, 56c...arm section, 56d...connecting shaft, 56e...first wall (upper surface)
56f: second wall (side surface), 56g: cylindrical body portion, 56h: fixing screw 59: auxiliary dust collection port 60: impact applying mechanism 60a: finger hook portion (operation member)
61: fixing screw 65: disposal port, 65a: engagement recess 66: lid, 66a: claw portion 67: opening/closing shaft 68: connection port 69: cap

Claims (10)

A portable cutting machine with a dust box,
A cutting machine body that houses an electric motor;
a blade cover for covering a blade rotated by the electric motor;
a dust box communicating with the cutting tool cover and having a peripheral wall along the periphery of the cutting tool for collecting cutting powder;
A connection port for connecting a dust collection hose provided on the dust box;
A ventilation opening is formed in an upper part of the peripheral wall in an area spanning the front and rear of the top part of the dust box, separate from the connection port , and through which dust-collecting wind generated by the rotation of the cutting tool is exhausted ;
A portable cutting machine with a dust box having a filter member attached to the ventilation opening. A portable cutting machine with a dust box according to claim 1, wherein the dust box has a cutting powder storage section that extends from the lower region of the ventilation opening to the rear region of the lower region and has a space for storing cutting powder. A portable cutting machine with a dust box according to claim 2, in which a backflow prevention wall is provided upstream of the cutting dust storage section to prevent the stored cutting dust from flowing back. A portable cutter with a dust box according to any one of claims 1 to 3, in which the filter member is a pleated filter having a number of parallel folds, and the folds are attached along the thickness direction of the cutting tool. The portable cutting machine with a dust box according to any one of claims 1 to 4, further comprising a movable cover that is provided on the cutting tool cover so as to be movable between a position covering a lower area of the cutting tool and a position exposing the lower area of the cutting tool,
The dust box has a dust collection port located above the cutting area by the cutting tool, and an auxiliary dust collection port located behind the dust collection port and in the movable area of the movable cover. A portable cutting machine with a dust box according to claim 5, wherein the dust box is provided with a guide section downstream of the dust collection port that extends the flow of dust collection air generated by the rotation of the cutting tool toward the ventilation opening. 7. The portable cutting machine with a dust box according to claim 1, wherein the peripheral wall of the dust box is arc-shaped along an outer periphery of the cutting tool,
The filter member is disposed in an arc shape along the peripheral wall. A portable cutting machine with a dust box according to any one of claims 1 to 7, which has a case body that houses the filter member, and the ventilation opening is formed on the upper surface of the case body. A portable cutter with a dust box according to any one of claims 1 to 8, wherein the dust box is provided with an impact mechanism for applying an impact to the filter member. 10. A portable cutting machine with a dust box according to claim 1, wherein the filter member is attached to the dust box across the top of the peripheral wall.

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