JP5087113B2 - Portable cutting tool and dust collection structure - Google Patents

Description

  The present invention relates to a handheld portable cutting tool that performs cutting work while an operator holds the main body of the tool, and a dust collection structure that is used by being attached to the cutting tool. The present invention relates to a portable cutting tool and a dust collection structure for rotating a disk-shaped rotary blade attached to a main body.

Generally, when cutting a workpiece such as concrete, the disc-shaped cutting blade (rotary blade) attached to the tool body is rotated, and the operator holds the tool body with his / her fingers to perform the cutting work. It is carried out. In this cutting operation, since the member to be cut is concrete or the like, a large amount of chips (dust) is generated from the member to be cut by the cutting blade that rotates during the operation. Therefore, the cutting tool provided with the structure which collects the dust which generate | occur | produces during cutting operation is proposed (for example, refer patent documents 1, 2).
For example, in the electric cutter disclosed in Patent Document 1, a dust collecting hose is attached to a part of the protective cover of the cutting blade, and the dust collecting hose is connected to an external electric dust collector or the like. It is aspirated and collected by such means.

  Further, in the cutting tool of Patent Document 2, an elastic member such as a winding spring is disposed between a base moving on a member to be cut and a foil cover, and the base and the foil cover are always separated by the elastic member. Proposals have been made to increase the dust collection effect by energizing most of the dust, including the dust that scatters substantially parallel to the surface of the member to be cut, at the start of cutting.

In a tool having a configuration that collects dust during the cutting operation as described above, since the scattering direction of the dust generated by the cutting changes depending on the cutting depth of the rotating blade, there is a portable cutting machine with a further improved configuration. Conventionally, it has been proposed (see, for example, Patent Document 3).
The portable cutting machine includes a base that moves on a part to be cut, a drive source built in a tool body that is rotatably connected to one end of the base, and a rotary blade that is rotationally driven by the drive source. A protective cover covering a part of the outer periphery of the rotary blade and a dust collecting cover provided on the protective cover, and a guide plate for guiding the dust collecting cover to the suction port can be rotated on the base. The configuration is provided.
The portable cutting machine performs a cutting operation while collecting dust generated from a member to be cut by rotating the rotary blade by suction from a dust collector connected to the dust cover via a hose. Yes.

JP 2008-149679 A JP 2004-058388 A JP 2009-023004 A

However, the following problems exist in the portable cutting machine provided with the conventional dust collecting mechanism.
In the portable cutting machine of Patent Document 3, when the cutting work is performed and moved, the kerf of the rotary blade formed on the member to be cut becomes longer, and dust is ejected to the outside through the kerf.
Also, in the case of a portable cutting machine, if the cutting edge is not visible when performing a cutting operation, the position of the cutting edge is determined when a guide line for guiding cutting such as a marking line is drawn in advance. Could not be adjusted visually.
Further, the portable cutting machine may be used at a work site where the dismantling work is performed, but particularly when performing the dismantling work, there is a case where the power tool is not available and thus cannot be used with the electric tool.

  Therefore, the present invention has been made in view of the above-mentioned problems, and dust collected by cutting work can be efficiently collected even if a cut groove is formed in a member to be cut and collected without impairing cutting workability. It is an object of the present invention to provide a portable cutting tool and a dust collection structure that can be used even at a work site without a power source.

The portable cutting tool according to the present invention has the following configuration in order to solve the above problems. That is, the portable cutting tool is connected to an air supply hose for supplying air, and has a main body portion having a driving turbine rotated by the air, and a disk-like shape attached to a driving shaft rotated by the driving turbine of the main body portion. And a dust collecting structure that collects dust generated when the rotary blade cuts the workpiece, and collects the dust while collecting dust through a dust collecting hose connected to the dust collecting structure. In the portable cutting tool for cutting a cutting member, the dust collection structure is provided over a predetermined angular range of the rotary blade so as to expose a predetermined arc range of the rotary blade, and the dust collection structure other than the exposed Branching from an arc-shaped protective cover body covering the cutting edge and the left and right side surfaces of the rotary blade, a dust collecting portion provided on one end side of the circular arc shape of the protective cover body, and an air flow path supplied by the air supply hose Before It includes an air branch hose which is connected to the dust collection unit. And in the said portable cutting tool, the said dust collection part is from the one end opening side of the cylindrical main body part which formed the opening groove in the position which opposes between the right-and-left side surfaces of the said protective cover body, and this cylindrical main body part. A first air blowing portion that blows out air supplied by the air branch hose, and a second air outlet that blows out air supplied by the air branch hose from the other end opening side of the cylindrical main body portion. ing. Further, in the portable cutting tool, the cylindrical main body portion is formed with a flow path in a plate thickness direction, and the first air blowing section and the second air blowing section are separated from the air branch hose by the flow path. Air is supplied, and the first air blowing portion blows out the air supplied from the air branch hose at a position of one side closed end surface of the cylindrical main body portion that is in a range facing the opening groove. And the second air blowing part is a dust collecting blowing hole for blowing out air supplied from the air branch hose to the inner peripheral side surface of the cylindrical main body part or the other closed end face of the cylindrical main body part. It is set as the structure formed.

According to such a configuration, the portable cutting tool is in a state in which the rotary blade is rotated by the supply of air from the air supply hose and the cutting work can be performed on the member to be cut, and the cylindrical main body of the dust collecting unit The air is sent from the first blowing part formed in the part to the member to be cut through the air branch hose, and the air is also blown from the second blowing part of the cylindrical main body part of the dust collecting part. An air flow is generated on the dust collecting hose side. Therefore, in the portable cutting tool, when the rotary blade comes into contact with the member to be cut, the cutting operation starts, dust is generated, and when the dust is sent out along the rotation direction of the rotary blade, the air from the first blowing part is It becomes an air curtain, suppresses the direction of dust ejection, and guides the dust to the dust collecting hose along the inner circumferential surface of the cylindrical main body of the dust collecting portion. In particular, in the portable cutting tool, when a cut groove is formed in the member to be cut by the rotary blade, the first blow-out portion is formed at a position where air is blown into the cut groove. Dust collection hose that functions effectively as a curtain, and that dust is minimally scattered over the air curtain, and the dust suppressed by the air curtain in the kerf along the cylindrical inner peripheral surface of the cylindrical main body Sent to.
In addition, the portable cutting tool blows out air sent from the air branch hose from the blowout hole formed on the one side closed end face of the cylindrical main body portion by the air flow path formed in the cylindrical main body portion. And the flow of the air which collect | recovers dust is formed with the air from the dust collection blowing hole formed in the other side obstruction | occlusion end surface of the cylindrical main-body part.

  And in the said portable cutting tool, the said 2nd air blowing part faces the inner peripheral side of the said cylindrical main body part, is supported by the said cylindrical main body part, and is in the direction which blows off air to the other end opening side. The air nozzle is directed to a dust collection outlet, and the air branch hose is connected to the air nozzle so as to supply air from the air branch hose.

  With this configuration, the portable cutting tool blows air from the air nozzle that is the second air blowing portion toward the other end opening side of the cylindrical main body portion, so that the opening from the opening groove and one end opening side of the cylindrical main body portion can be achieved. Creates a flow of air that efficiently sends dust from the workpiece to the dust collection hose. In addition, since the air nozzle is in a desired position on the inner peripheral surface of the cylindrical main body, the air flow formed on the inner peripheral surface of the cylindrical main body flows around the dust collection outlet of the air nozzle, and dust is generated in the air nozzle. It becomes difficult to adhere to the dust collection outlet.

  Further, in the portable cutting tool, the protective cover body is driven from the main body so that an opening end portion that exposes the rotary blade comes into contact when the rotary blade is cut into a member to be cut. A guide portion that is linearly formed at a position on the side of the member to be cut beyond the axis, and when the guide portion abuts on the member to be cut, a part of the cutting edge of the rotary blade is protected. It is good also as a structure which has a notch part formed by notching the end side of the said linear guide part so that it may expose from a cover body.

  According to this configuration, the portable cutting tool operates the cutting edge of the rotary blade from the notch when the cutting operation is performed with the guide portion at the opening end of the protective cover body in contact with the workpiece. The person can work while watching. Therefore, especially when the marking line is displayed, the operator can perform work while visually recognizing the marking line and the blade edge.

  Further, in the portable cutting tool, the notch portion is provided between the rotary blade and the protective cover body in the range of the notch portion, and is provided with a dustproof member toward the rotary blade. A member is good also as a structure installed so that the said rotary blade may be adjoined in the range of the said notch part.

  According to such a configuration, the portable cutting tool is in a state in which the cutout portion and the member to be cut are separated when the opening end portion of the protective cover body is in contact with the member to be cut, but the dustproof member rotates. By being installed adjacent to the blade, it is possible to prevent the dust from being ejected out of the protective cover body by the dust-proof member even if the dust is sent out as the rotary blade rotates.

Furthermore, in the portable cutting tool, the dust collecting portion is a tapered inner peripheral surface in which a space gradually narrows from the other closed end surface of the cylindrical main body portion continuously to the other closed end surface of the cylindrical main body portion. It is good also as a structure which provided the cylindrical taper part which has these.
With this configuration, when the portable cutting tool blows air from the dust collection outlet toward the cylindrical taper portion from the cylindrical main body portion, the blown air flows from the flow path having a large diameter along the taper inner peripheral surface. By flowing through the small diameter flow path, the flow velocity becomes faster, and the dust collection state of the dust flowing in from the opening groove and the opening of the cylindrical main body is improved.

The portable cutting tool may further include a connection interposition part for connecting the air branch hose between the main body part and the air supply hose, and the air branch hose includes the connection interposition part and the cylindrical shape. It is good also as a structure connected to a main-body part.
With this configuration, the portable cutting tool connects the connection interposition part between the main body part and the air supply hose, and connects the air branch hose between the connected connection interposition part and the cylindrical main body part. The structure held by the operator can be refreshed and the workability is excellent.

And in the said portable cutting tool, the said protective cover body is the brush provided in the line shape so that it may contact the board | substrate of the said rotary blade between the said drive shaft side and the blade edge | tip side of the said rotary blade inside it. It is good also as a structure which has a shape-shaped inscribed member.
With this configuration, the portable cutting tool can guide the dust caught by the rotation of the rotary blade to the opening groove side of the dust collecting portion by the inscribed portion and send the dust to the dust collecting hose.

Furthermore, in the portable cutting tool, a connection pipe for connecting the dust collecting hose is provided so that the cylindrical main body protrudes in the cylinder axial direction from the cylinder outer peripheral side of the other end opening. The inner peripheral diameter of the main body is larger than or equal to the inner peripheral diameter of the connecting pipe.
With this configuration, in the portable cutting tool, the suction force that the air blown from the second air blowing portion smoothly flows and sucks from the connection pipe to the dust collecting hose side is improved. In particular, when the inner peripheral diameter (inner diameter) of the cylindrical main body and the inner peripheral diameter (inner diameter) of the connecting pipe are formed to the same dimension, the suction force is greatly improved.

Moreover, in the portable cutting tool, the cylindrical main body portion is located on the inner diameter side from the center (center line) at the other closed end surface that forms the second air blowing portion, which is the other end opening side. It was set as the structure which formed the dust collection blowing hole of the 2nd air blowing part.
With this configuration, the portable cutting tool can be used to collect dust even if dust collected by moisture contained in the air blown from the second air blowing portion adheres to the periphery of the dust collecting blow hole of the second air blowing portion. Since the hole is located in the center or on the inner diameter side, the inner side of the peripheral edge of the deposit to which dust adheres can be made to protrude to the inner diameter side from the other closed end face. Therefore, the dust deposits deposited on the peripheral edge of the dust collection blowout hole are peeled off from the dust collection blowout hole by receiving the air flow at the portion protruding toward the inner diameter side.

The dust collecting structure is around the drive shaft of a portable cutting tool that rotates a disk-shaped rotary blade attached to the drive shaft by air supplied from an air supply hose to cut a member to be cut. A dust collecting structure that is detachably attached to a support part and used, and is provided over a predetermined angular range of the rotary blade so as to expose a predetermined arc range of the rotary blade, and other than the exposed Branching from an arc-shaped protective cover body covering the cutting edge and the left and right side surfaces of the rotary blade, a dust collecting portion provided on one end side of the circular arc shape of the protective cover body, and an air flow path supplied by the air supply hose An air branch hose connected to the dust collecting part, and the dust collecting part includes a cylindrical main body part having an opening groove formed between the left and right side surfaces of the protective cover body. The air component from the one end opening side of the cylindrical main body. It has a first air-blowing unit for blowing the supplied air by hoses, and a second air-blowing unit for blowing the supplied air by the air branch hose from the other end opening of the tubular body portion, the cylindrical The main body part is formed with a flow path in the plate thickness direction, and air from the air branch hose is supplied to the first air blowing part and the second air blowing part by the flow path, and the first air blowing part Is formed with a blowout hole for blowing out the air supplied from the air branch hose at the position of the one side closed end face of the cylindrical main body within the range facing the opening groove, and the second air blowout part is A dust collection blowout hole for blowing out the air supplied from the air branch hose is formed on the inner peripheral side surface of the cylindrical main body portion or the other closed end surface of the cylindrical main body portion .

With this configuration, the dust collection structure can be used by being detachably attached to a portable cutting tool, and dust generated when cutting a member to be cut with a rotary blade is the first of the cylindrical main body. Scattering by the air from the air blowing part is suppressed, and the air flow blown out from the second air blowing part of the cylindrical main body part is guided to the cylinder inner peripheral surface of the cylindrical main body of the dust collecting part. Dust is collected. In particular, in the dust collection structure, when the cut groove is formed in the member to be cut by the rotary blade, the first blow-out portion is formed at a position where the air is blown into the cut groove. It functions effectively as a curtain, and it is minimized that dust is scattered over the air curtain, and dust suppressed by the air curtain in the kerf is connected along the cylinder inner peripheral surface of the cylindrical main body. Sent to the dust collection hose. In addition, the dust collection structure is an air curtain which blows air sent from the air branch hose through a blowout hole formed on one side closed end surface of the cylindrical main body portion by an air flow path formed in the cylindrical main body portion. And the flow of the air which collect | recovers dust is formed with the air from the dust collection blowing hole formed in the other side obstruction | occlusion end surface of the cylindrical main-body part.

Furthermore, in the dust collection structure, the cylindrical main body portion is provided with a connection pipe for connecting a dust collection hose for dust collection so as to protrude in the cylinder axial direction from the cylinder outer peripheral side of the other end opening. The inner peripheral diameter (inner diameter) of the cylindrical main body is larger than or equal to the inner peripheral diameter (inner diameter) of the connecting pipe.
With this configuration, the dust collection structure has an improved suction force that allows the air blown from the second air blowing portion to smoothly flow from the connection pipe to the dust collection hose side and be sucked. In particular, when the inner peripheral diameter of the cylindrical main body and the inner peripheral diameter of the connecting pipe are formed to the same dimension, the suction force is greatly improved.

Further, in the dust collecting structure, the cylindrical main body portion is located on the other end opening side, and the second air outlet is formed on the inner side from the center on the other closed end surface forming the second air outlet. A dust collection outlet hole was formed.
With this configuration, the dust collecting structure can be used even if dust collected by moisture contained in the air blown from the second air blowing portion adheres to the periphery of the dust collecting blow hole of the second air blowing portion. Since the hole is located on the inner diameter side from the center (center line), the inner side of the peripheral edge of the deposit to which dust adheres can be made to protrude to the inner diameter side from the other closed end face. Therefore, the dust deposits deposited on the peripheral edge of the dust collection blowout hole are peeled off from the dust collection blowout hole by receiving the air flow at the portion protruding toward the inner diameter side.

The portable cutting tool according to the present invention has the following excellent effects.
The portable cutting tool divides the air that rotates the rotary blade, and the air is blown out from the first air blowing portion and the second air blowing portion of the cylindrical main body by the dust collecting portion provided in the protective cover body. In addition to forming an air curtain, it is possible to form an air flow for collecting dust and reliably collect dust. In particular, even in a work site where there is no power supply, a portable cutting tool, for example, rotates the rotary blade and forms an air curtain for the dust collection unit and an air flow that draws dust by air from the compressor. Cutting work and dust collection work can be performed efficiently. Moreover, even if the portable cutting tool is in the state where the kerf is formed by the rotary blade, the air from the blowout hole is blown into the kerf to form an air curtain in the groove, and dust can be efficiently collected.
In addition, the portable cutting tool forms an air flow path inside the cylindrical main body, and blows out air from the outlet hole on the one closed end face of the cylindrical main body and the dust collection outlet on the other closed end face. The dust generated by cutting work is collected from the cylindrical inner peripheral surface of the cylindrical main body, so that the work environment can be improved.

The portable cutting tool has a notch that exposes the blade edge of the rotary blade at the opening end of the protective cover body. If a marking line is shown, the marking line and blade edge are visible. The cutting work of the member to be cut can be performed.
The portable cutting tool is provided with a dust-proof member adjacent to the rotary blade at the notch where the cutting edge of the rotary blade is exposed, so that dust is not sent out from the notch, improving workability and working environment. Can be improved.

The portable cutting tool can increase the suction force and improve the dust collection effect by forming the inner diameter of the cylindrical main body to be larger or the same size as the inner diameter of the dust collection hose. it can.
In the portable cutting tool, since the dust collection blowing hole of the second air blowing part is formed on the inner diameter side from the center at the other side closed end face, dust accumulated in the dust collecting blowing hole can be removed by the flow of air. Therefore, the suction force does not decrease during the work, and the work can be performed continuously.

Since the portable cutting tool is provided with the cylindrical taper portion in the cylindrical main body, the flow rate of the air blown out from the dust collection outlet is increased, and the dust collection efficiency can be further improved.
Since the portable cutting tool connects the air branch hose to the cylindrical body of the dust collector via the connection interposition part, the shape of the body part operated by the operator can be simplified and the total weight can be reduced. it can.

In the portable cutting tool, the protective cover body can collect the dust caught by the rotation of the rotary blade from the opening groove of the dust collecting part by the inscribed member that contacts the substrate of the rotary blade, and further improves the dust collection efficiency. Can be improved.
In addition, since the dust collection structure is detachably attached to the portable rotary tool, it can be attached and operated even if the configuration is slightly different depending on the manufacturer, and the dust generated when cutting work can be collected. Can be improved.

The dust collection structure can increase the suction force and improve the dust collection effect by forming the inner diameter of the cylindrical main body to be larger or the same size as the inner diameter of the dust collection hose. it can.
In the dust collection structure, the dust collection blowing hole of the second air blowing part is formed on the inner diameter side from the center on the other closed end face, so that dust deposits accumulated in the dust collection blowing hole can be removed by the air flow. Therefore, the suction force does not decrease during the work, and the work can be performed continuously.

It is a perspective view showing the whole portable cutting tool concerning the present invention. It is a disassembled perspective view which shows typically the state which decomposed | disassembled each structure of the portable cutting tool which concerns on this invention. It is a side view showing the whole portable cutting tool concerning the present invention. It is a front view which notches and shows a part of portable cutting tool which concerns on this invention. It is a perspective view showing a dust collection part of a portable cutting tool concerning the present invention typically with a part cut away. (A)-(e) is the perspective view and partial sectional view which show the state which prepares the portable cutting tool which concerns on this invention typically in order. (A)-(c) is a side view which abbreviate | omits a state which performs a cutting operation with the portable cutting tool which concerns on this invention, and is shown typically. (A), (b) is a side view which shows typically a state which abbreviate | omitted some cutting operations with the portable cutting tool which concerns on this invention. It is a side view which shows the other structure of the air branch hose of the portable cutting tool which concerns on this invention. FIG. 3 is a front view schematically showing a part of the air adjusting mechanism in the blowout hole of the portable cutting tool according to the present invention with a part thereof omitted. (A), (b) is a side view and a front view schematically showing a partially omitted other forms in the first air-blowing unit is a reference example of a cutting tool for mobile. (A ) is a front view which shows the other structure of the blowing hole in the 1st air blowing part of the portable cutting tool which concerns on this invention, (b) is a front view which is a reference example which shows the other structure of the blowing hole. is there. It is a perspective view which cuts off some other structures in the cylindrical main-body part of the portable cutting tool which concerns on this invention, and shows it. It is sectional drawing which shows the other structure in the cylindrical main-body part of the portable cutting tool which concerns on this invention. (A)-(c) is sectional drawing which shows the position of the dust collection blowing hole of the portable cutting tool which concerns on this invention, (a) is sectional drawing in Va-Va of (b), (b) is Sectional drawing in Vb-Vb of (a), (c) is sectional drawing which expands and shows a part of (b). The portable cutting tool is shown, (a) is a perspective view showing a configuration in which the first air blowing portion as a reference example is a blowing nozzle, and the blowing nozzle can protrude and retract with respect to one end of the cylindrical main body portion. b) is a sectional view showing a state of the output nozzles is a reference example, (c) is a perspective view showing a partially cutaway the second air-blowing unit Ru engaged to the present invention as an air nozzle. The portable cutting tool which concerns on this invention is shown, (a) is the side view which notched a part which used the 2nd air blowing part as the air nozzle, (b) is a cylindrical main body by using the 2nd air blowing part as an air nozzle. It is a front view which notches and shows a part. The portable cutting tool which concerns on this invention is shown, (a) is a schematic diagram which shows typically the use condition of a portable cutting tool, (b), (c) shows the other structure of a cylindrical main-body part, respectively. It is a schematic diagram.

Hereinafter, a portable cutting tool according to the present invention will be described with reference to the drawings.
As shown in FIG. 1, the portable cutting tool 1 supplies air to rotate the rotary blade 9 at a high speed, and the operator operates the main body 2 while holding it with fingers, so that the member W to be cut such as concrete can be obtained. Work is performed by collecting dust generated when cutting. This portable cutting tool 1 is detachably attached to a main body portion 2 for connecting an air supply hose Ah from a compressor CP and a support portion 7 of the main body portion 2, and covers a predetermined arc range of the rotary blade 9 for cutting. And a dust collection structure 10 that collects dust generated during work.

  The portable cutting tool 1 connects the air supply hose Ah to the main body part 2 via the connection interposition part 25, and the air branch hose between the dust collection part 14 and the connection interposition part 25 of the dust collection structure 10. 20 is connected, and further, a dust collecting hose Sh is connected to the rear side of the dust collecting portion 14. The portable cutting tool 1 rotates the rotary blade 9 by supplying air from the compressor CP, and forms an air flow from the dust collecting portion 14 to the dust collecting hose Sh by the air from the air branch hose 20. At the same time, it is used in a state where air is blown out toward the member to be cut W from a blowout hole 16a described later.

Hereinafter, each structure of the portable cutting tool 1 is demonstrated.
As shown in FIG. 1 and FIG. 2, the main body 2 includes a hose connection part 3 that connects an air supply hose Ah to the rear side of the main body part 2 via a connection interposition part 25, and an air formed inside the hose connection part 3. A flow path 4, a drive turbine 5 provided along the air flow path 4, a drive shaft 6 rotated by the rotation of the drive turbine 5, and a dust collection structure described later around the drive shaft (spindle) 6 A support part 7 for supporting the body 10 and a discharge part 8 for releasing the air flowing through the air flow path 4 to the outside are provided. A handle connection hole 2a for detachably attaching the handle Ha is formed on the side surface of the main body 2 corresponding to the drive turbine 5.

The hose connection part 3 may be of any structure as long as it does not leak by connecting the connection interposition part 25 when air from the compressor CP is sent, and is formed, for example, by a screw structure.
The air flow path 4 is formed so as to be a flow path of the air sent from the hose connection part 3 to the discharge part 8, and the diameter and arrangement thereof are set so that the drive turbine 5 is efficiently rotated. Yes.
The drive turbine 5 is rotated at high speed by the air sent from the air flow path 4, and is provided so that the drive turbine 5 and the drive shaft 6 rotate in conjunction with each other.
The drive shaft 6 is provided so as to protrude in a cylindrical shape from the housing side of the main body 2, and here a screw is formed on the inside so that a rotary blade 9 described later can be detachably installed. Yes.

The support portion 7 is formed around the drive shaft 6 so as to protrude from the housing in a ring shape, and is a portion where a dust collection structure 10 described later is detachably installed.
The discharge part 8 discharges the air flowing through the air flow path 4 to the outside of the main body part 2, and is formed so as to protrude from the casing so as to blow out air below the main body part 2.

  The rotary blade 9 is configured to be attached together with a dust collection structure 10 to be described later, or can be attached after the dust collection structure 10 is attached to the main body 2. The rotary blade 9 is detachably attached to the drive shaft 6 via an attachment member 9A. The attachment member 9A has a wheel washer 9a, a bush 9b, a wheel retaining nut 9c, and a bolt 9d. The rotary blade 9 is inserted into the drive shaft 6 after the wheel washer 9 a and the bush 9 b are first inserted into the drive shaft 6 and attached to the drive shaft 6. And the rotary blade 9 is attached by being fixed to the drive shaft 6 with the volt | bolt 9d so that it may be clamped by the wheel stop nut 9c and the bush 9b. The outer diameter of each component of the attachment member 9A is formed to be smaller than the attachment holes 11d and 11d formed in the left and right side plates 11a and 11b of the dust collection structure 10 to be described later.

  As shown in FIGS. 1 and 2, the dust collection structure 10 is installed by being fixed to the support portion 7 of the main body portion 2 by the attachment portion 11 e, and the member W to be cut is cut by the rotary blade 9 described later. It is intended to collect dust that is sometimes generated. The dust collecting structure 10 includes an arc-shaped protective cover body 11, a dust collecting portion 14 provided at one end (lower end side) of the arc of the protective cover body 11, the dust collecting portion 14 and the connection interposed portion 25. And an air branch hose 20 attached between the two.

  The protective cover body 11 protects the operator's fingers and the like and suppresses scattering of generated dust. The protective cover body 11 is made of, for example, a metal plate and is formed so as to expose a predetermined arc range of the rotary blade 9. The protective cover body 11 is attached to the left and right side plates (side surfaces) 11a and 11b of the rotary blade 9, a peripheral plate 11c that covers the cutting edge portion of the rotary blade 9, and a ring shape that protrudes from the left side plate 11a. A mounting portion 11d, mounting holes 11d and 11d formed in the right side plate 11b on the inner side of the mounting portion 11e, and a position opposite thereto, a guide portion 11f formed on the opposite end surface of the peripheral surface plate 11c, and the guide portion 11f is formed at one end of 11f.

The left and right side plates 11 a and 11 b are provided in such a size as to form the open end of the rotary blade 9 at a position beyond the drive shaft 6 from the cutting edge on one side of the rotary blade 9. That is, when the cutting length from the cutting edge to the center of the rotary blade 9 is 100%, the left and right side plates are exposed to the rotary blade 9 so that the cutting length is 50% or more from the cutting edge of the rotary blade 9. 11a and 11b are formed. The left and right side plates 11a and 11b each have a mounting hole 11d, which is formed larger than the outer diameter of the mounting member 9A of the rotary blade 9.
The peripheral surface plate 11c is formed so as to cover the cutting edge of the rotary blade 9 at the peripheral end positions of the left and right side surface plates 11a and 11b. The peripheral plate 11c and the left and right side plates 11a and 11b are configured to cover the rotary blade 9 within a predetermined arc range.

  As shown in FIGS. 1, 3, and 4, an inscribed member 30 is provided inside the left and right side plates 11a and 11b. The inscribed member 30 is for guiding dust generated when the rotary blade 9 cuts the workpiece W to the dust collecting portion 14. Here, the inscribed member 30 is a linear arrangement of brush-like members from the inner diameter side to the outer diameter side of the substrate of the rotary blade 9. As shown in FIG. 4, the inscribed member 30 is provided so that the base end side of the brush is fixed to the left and right side plates 11 a and 11 b, and the tip end side of the brush is in contact with the substrate of the rotary blade 9. The inscribed member 30 is installed in a state where a linearly arranged brush is inclined at a predetermined angle. The material of the inscribed member 30 is formed of a material that does not easily overheat even if it is rubbed.

As shown in FIGS. 1 and 2, the attachment portion 11 e includes a fixed portion 11 e ₁ and a separation portion 11 e ₂ that is fastened to the fixed portion with screws or the like. The fixed portion 11e ₁ is formed so as to protrude in a state where flanges are formed at both ends of a semicircular ring shape around the mounting hole 11d of one side plate 11a. Further, the separation portion 11e ₂ that forms a pair with the fixed portion 11e ₁ is formed in a shape in which flanges are provided at both ends of a semicircular ring shape. Further, the flanges of the fixing portion 11e ₁ and the separating portion 11e ₂ are formed with screw holes, and are for fixing with a fastening means (not shown) such as a bolt. Attachment portion 11e is in a state of being opposed to the fixed portion 11e ₁ and spaced area 11e _2, are disposed along the support portion 7 of the main body portion 2, by tightening the both sides of the support 7 by hooking means not shown It is attached to the support part 7. When the attachment portion 11 e is attached to the support portion 7, the attachment height is adjusted with respect to the support portion 7 so that the rotary blade 9 is positioned at the center of the protective cover body 11. .

  As shown in FIGS. 1 and 3, the guide portion 11 f is a member that contacts the workpiece W and guides it in the cutting direction. The guide part 11f is linearly formed at the opening end of the protective cover body 11 on the workpiece W side. Here, the guide portion 11f is formed so as to be continuously collinear up to an opening end portion of the dust collection portion 14 described later. 11 f of guide parts are comprised by attaching the board member used as the width | variety larger than the width | variety of the board thickness to the edge part of the side plates 11a and 11b on either side. As shown in FIG. 3, the guide portion 11 f is configured to be parallel to the vertical line L <b> 1 orthogonal to the longitudinal direction of the main body portion 2.

  As shown in FIG. 3, the notch portion 11g is notched at a predetermined angle so that the upper end side of the guide portion 11f is exposed when a part of the cutting edge of the rotary blade 9 comes into contact with the workpiece W. Formed. In this notch portion 11g, here, a fixed plate piece 12a fixed across the positions on both sides of the rotary blade 9, and the same shape as this fixed plate piece 12a is supported by the fixed plate piece 12a by screws or the like. The member support part 12 which consists of the support plate piece 12b is installed. The member support portion 12 is formed of a metal piece and is used for installing the dustproof member 13 in a state adjacent to the rotary blade 9.

  And the member support part 12 provided in the notch part 11g pinches the dust-proof member 13 by the fixed plate piece 12a and the support plate piece 12b, and supports it so that it may be in the position adjacent to the blade edge of the rotary blade 9. Yes. The dust-proof member 13 is preferably a soft member that is a sheet-like member such as a rubber piece or a non-woven fabric that is difficult to be heated and hardly worn even when the rotary blade 9 contacts. By attaching the dust-proof member 13 in the state of being adjacent to the rotary blade 9 within the range of the notch portion 11g, the dust-proof member 13 is notched even if there is dust caught in the protective cover body 11 due to the rotation of the rotary blade 9. Blowing out from the part 11g is prevented. Moreover, as shown in FIG. 3, since the operator can visually recognize the cutting edge of the rotary blade 9, when the marking line is shown on the workpiece W, the cutting edge and the marking line are visually recognized. It becomes possible to perform cutting work while doing.

  As shown in FIGS. 1 and 2, the dust collecting portion 14 is provided on the lower end side (one end side) of the arc of the protective cover body 11 and is generated when the workpiece W is cut by the rotary blade 9. It collects dust. The dust collecting portion 14 includes a cylindrical main body portion 15 having an opening groove 15a formed so as to face between the left and right side plates 11a and 11b of the protective cover body 11, and the one end opening 15c side of the cylindrical main body portion 15. The first air blowing part 16 that blows air from, the second air blowing part 17 that blows air from the other end opening 15e side of the cylindrical main body part 15, the first air blowing part 16 and the second air blowing part 17 And a flow path 15b for supplying air. The dust collecting portion 14 further has a cylindrical taper portion 18 provided on the other end opening 15 e side of the cylindrical main body portion 15, and a connecting pipe 19 of the dust collecting hose Sh on the rear end side of the cylindrical taper portion 18. Is provided.

  As shown in FIG. 5, the cylindrical main body 15 has an opening groove 15a on the side surface along the cylinder axis direction, receives dust from the one end opening 15c side and the opening groove 15a side, and the other end opening 15e. The received dust is sent to the side. The cylindrical main body 15 is formed so that an air flow path 15b can be provided inside in the thickness direction. That is, the cylindrical main body portion 15 is configured to supply air supplied from an air branch hose 20 described later to the first air blowing portion 16 and the second air blowing portion 17 via the flow path 15b. . Here, the flow path 15b of the cylindrical main body portion 15 indicates a space formed between the inner tube and the outer tube. That is, the cylindrical main body 15 is an end face plate that forms an inner tube, an outer tube, one side closed end surface 16b, and the other side closed end surface 17b, and a space (flow path) is formed inside the cylindrical main body portion 15. It has a configuration. The cylindrical main body 15 blows air from a blowout hole 16a of one side closed end face 16b to be described later, and receives dust from the opening groove 15a and one end opening 15c to the cylinder inner peripheral face 15d side, and the other end side. The air is blown out through a dust collection outlet 17a of the other closed end face 17b which will be described later so that dust is sent out from the other end opening 15e to the dust collection hose Sh. Here, the cylindrical main body 15 is formed of a metal that is the same material as the protective cover body 11.

  The first air blowing part 16 forms a blowing hole 16 a in the one side closed end face 16 b of the cylindrical main body part 15. The blowout hole 16a is provided on the one closed end face 16b so as to be positioned between the left and right side plates 11a, 11b of the protective cover body 11. Here, the blowout hole 16a is formed at a position facing the rotary blade 9, that is, an extension line of the rotary blade 9 (a central position between the side plates 11a and 11b). This blowing hole 16a is configured to blow air toward the front side (the member to be cut W). When the rotation direction of the rotary blade 9 is clockwise, the first air blowing section 16 configured in this way is subjected to cutting work and is left and right at a predetermined angle from the workpiece W toward the floor surface. The air blown from the blowing holes 16a of the first air blowing section 16 when a dust flow occurs at substantially the width interval between the side plates 11a and 11b is used as an air curtain.

  Therefore, the dust generated by the air curtain by the air from the blowout hole 16a hardly goes to the floor surface side beyond the air curtain, and from the one end opening 15c of the cylindrical main body portion 15 to the inside of the cylindrical main body portion. It is guided and accepted on the peripheral surface 15d side. In particular, the air blown from the blow hole 16a forms an air curtain in the kerf by blowing air into the kerf when the kerf is formed in the workpiece W by the rotary blade 9. Works well. That is, when the blowout hole 16a is at a position corresponding to between the left and right side plates 11a and 11b, it faces the generation path of dust generated by the rotation of the rotary blade 9 (the flow of dust generated from the workpiece W). Thus, since the air curtain can be formed, dust scattering can be efficiently prevented. That is, the position of the blowout hole 16a facing between the left and right side plates 11a and 11b here is important that air is blown into the cut groove, and the substrate thickness of the rotary blade 9 is extended. A range from the position on the line to the space between the left and right side plates 11a and 11b is shown as the maximum range.

And the 2nd air blowing part 17 forms the flow of an airflow so that it may go to the other end opening 15e from the opening groove | channel 15a and the one end opening 15c of the cylindrical main-body part 15. FIG.
As shown in FIG. 5, the second air blowing portion 17 has a plurality of dust collection blowing holes 17 a formed on the other closed end surface 17 b of the cylindrical main body portion 15 (six locations in the drawing). The dust collection outlet 17a is configured to blow air toward the connected dust collection hose Sh. Therefore, when air is blown out from the dust collection blowout hole 17a by the supplied air, a flow of air (airflow) is formed from the one end opening 15c and the opening groove 15a toward the other end opening 15e as described above. Will be. Therefore, the dust induced by the air curtain of the blowout hole 16a can be collected and collected by the cylindrical main body 15 through the air flow formed by the second air blowout part 17. In addition, the cylindrical taper part 18 is provided as a structure which strengthens the flow of the airflow in the cylindrical main-body part 15 further.

  The cylindrical tapered portion 18 is a tapered inner peripheral surface whose space gradually narrows from the cylindrical main body portion 15 toward the connecting pipe 19 so as to narrow the flow path of air blown from the second air blowing portion 17. Is formed. Since the cylindrical taper portion 18 accelerates the flow velocity of the air blown from the second air blowing portion 17 and flows toward the dust collecting hose Sh, the opening groove 15a and the one end opening 15c of the cylindrical main body portion 15 are provided. It is possible to accelerate the airflow flowing from the first to the other end opening 15e, and to increase the dust collection efficiency of the generated dust. In addition, the cylindrical taper part 18 is formed with the metal which is the same material as the cylindrical main-body part 15 here.

  The connection pipe 19 is for detachably connecting the dust collecting hose Sh. Here, the connecting pipe 19 is formed to have a diameter large enough to connect the dust collecting hose Sh. The connecting pipe 19 is made of a metal that is the same material as the cylindrical tapered portion 18.

  As shown in FIGS. 1 to 3, the air branch hose 20 is provided between the dust collection portion 14 and the connection interposition portion 25 connected to the hose connection portion 3 at the rear end of the main body portion 2 and the air supply hose Ah. Are connected to supply air from the air supply hose Ah to the dust collecting portion 14. The air branch hose 20 includes one end side connection portion 22, an air adjustment screw 22 a provided on the one end side connection portion 22, the other end side connection portion 23, the one end side connection portion 22, and the other end side connection portion 23. A hose body 21 provided therebetween. And the air branch hose 20 connects the one end side connection part 22 to the branch hose connection part 29 of the connection interposition part 25, and connects the other end side connection part 23 to the cylinder outer peripheral surface of the cylindrical main body part 15 of the dust collection part 14. The first air blowing portion 16 and the second air blowing portion 17 are connected to the hose connecting portion 14a provided on the air supply hose Ah and flow from the air supply hose Ah through the flow path 15b of the cylindrical main body portion 15. To supply.

  In the air branch hose 20, an air adjusting screw 22a for adjusting the amount of air branch is attached to a member that connects the one end side connection portion 22 to the air supply hose Ah. The air adjusting screw 22a adjusts the amount of air branching by adjusting the degree of opening of the inlet through which the air is branched depending on the rotation angle or the number of rotations. The relationship between the one end side connection portion 22 and the air adjusting screw 22a is not a special configuration, and can be mounted by pressing the one end side connection portion 22 toward the branch hose connection portion 29 and releasing it. The thing of general structures, such as an attachment structure which can cancel | release installation by pushing the part 22 toward the branch hose connection part 29, is used. The air adjusting screw 22a can adjust the air flow rate by rotating it by a predetermined angle.

  The connection interposition part 25 is interposed between the air supply hose Ah and the hose connection part 3 of the main body part 2 to connect them, and connects the one end side connection part 22 of the air branch hose 20. The connection interposition part 25 includes an interposition part main body 26, a supply hose connection part 27 formed on one end side of the interposition part main body 26, a tool side connection part 28 formed on the other end side, and an outer surface of the interposition part main body 26. And a branch hose connection part 29 formed so as to protrude from the center. The supply hose connection part 27 of the connection interposition part 25 is formed so that the air supply hose Ah corresponds to a general standard diameter and mounting structure used in the compressor CP. And the tool side connection part 28 of the connection interposition part 25 is formed so that it may correspond to the general attachment structure connected to the connection part of the cutting tool which operate | moves with the commercially available air. Moreover, the connection interposition part 25 is attached with the dust collection structure 10 which can collect | recover the dust which generate | occur | produces also with respect to the cutting tool which operate | moves with the existing air because the branch hose connection part 29 is formed. Can do.

  As shown in FIG. 2, the dust collection hose Sh connected to the connection pipe 19 of the dust collection section 14 may be a general one formed of plastic or the like, and is connected to the other end side of the dust collection hose Sh. Is attached with a dust collection bag Sb for collecting dust. The dust collection bag Sb is formed of, for example, a non-woven fabric, and has a configuration that allows air to flow out of the bag to store dust and to form an air flow formed to carry the dust. .

Next, the operation of the portable cutting tool 1 will be described.
First, as shown in FIG. 6A, the rotary blade 9 is attached to the drive shaft 6 of the main body 2 via the attachment member 9 </ b> A in a state of being disposed between the left and right side plates 11 a and 11 b of the protective cover body 11. . Then, as shown in FIG. 6B, the attachment portion 11 e of the protective cover body 11 is attached to the support portion 7 while adjusting the attachment position. At this time, as shown in FIG. 6 (c), since the rotary blade 9 is already fixed to the drive shaft 6 of the main body 2, the rotary blade 9 is positioned at the center of the left and right side plates 11a, 11b. The protective cover body 11 is installed in the main body 2 by adjusting the mounting position and attaching the mounting portion 11 e to the support portion 7. As shown in FIG. 6 (d), when the protective cover 11 is attached to the main body 2 of the tool, the connection interposition 25 is connected to the hose connection 3 of the main body 2, and the connection interposition 25 is supplied. The air supply hose Ah is connected to the hose connection part 27. And the one end side connection part 22 and the other end side connection part 23 of the air branch hose 20 are connected to the branch hose connection part 29 of the connection interposition part 25 and the hose connection part 14a of the dust collection part 14.

  As shown in FIG. 6E, the dust collecting hose Sh is connected to the connecting pipe 19 of the dust collecting portion 14, and the dust collecting bag Sb is connected to one end of the dust collecting hose Sh. The connection order of the air supply hose Ah, the connection interposition part 25, the dust collection hose Sh, and the dust collection bag Sb is not particularly limited. When the working preparation as the portable cutting tool 1 is completed, air is sent from the compressor CP, and the rotating state of the rotary blade 9 and the air blowing state from the blowing hole 16a of the dust collecting unit 14 are adjusted if necessary. Adjust by 22a. In this way, the portable cutting tool 1 starts the cutting operation of the member W to be cut.

  As shown in FIG. 7A, when the operator operates the portable cutting tool 1, for example, the basic posture is that the body portion 2 is at a position orthogonal to the work surface of the member W to be cut. Then, as shown in FIG. 7 (b), the cutting operation is started in a state where the body portion 2 is tilted by positioning the rear portion of the main body portion 2 downward from the front. When the cutting operation starts, dust, which is a chip, is generated from the workpiece W along the rotation direction by the rotation of the rotary blade 9. In the portable cutting tool 1, when dust is generated, air is blown out from the blowing hole 16a formed in the one-side closed end surface 16b of the cylindrical main body portion 15 of the dust collecting portion 14. That is, in the portable cutting tool 1, the air of the compressor CP is blown from the blow hole 16 a by being sent from the flow path 15 b (see FIG. 5) of the cylindrical main body portion 15 through the air branch hose 20. The air blown out from the blowout holes 16a becomes an air curtain against dust, and the generated dust is prevented from scattering over the air curtain to the floor surface side.

  Therefore, as shown in FIGS. 7B and 7C, the dust generated by the cutting operation is guided to one end opening 15 c of the cylindrical main body portion 15 of the dust collection portion 14. At this time, air from the air branch hose 20 is blown out from the dust collection outlet 17a of the second air outlet 17 through the flow path 15b (see FIG. 5) on the cylinder inner peripheral surface 15d side of the cylindrical main body 15. Thus, an air flow is formed on the dust collecting hose Sh side. Therefore, the dust sent to the one end opening 15 c side of the cylindrical main body 15 or the opening groove 15 a is caused from the cylinder inner peripheral surface 15 d of the cylindrical main body 15 by the air flow formed by the second air blowing portion 17. It is sent toward the other end opening 15e. In addition, the flow of air in the cylindrical main body portion 15 is provided with the cylindrical taper portion 18 so that the diameter of the flow path through which the air flows becomes smaller, and the dust can be collected more smoothly. It is in a state that can be.

Even if dust generated by the cutting operation of the rotary blade 9 is caught in the protective cover body 11 from the opening end of the protective cover body 11 by the rotation of the rotary blade 9, the dust is dusted by the inscribed member 30. Is guided to the opening groove 15 a side of the cylindrical main body portion 15 in the dust collection portion 14.
In addition, the dust generated in connection with the cutting operation is stored in the dust collection bag Sb from the dust collection unit 14 via the dust collection hose Sh. The air that has carried dust to the dust bag Sb is discharged to the outside from the dust bag Sb (see FIG. 8B).

  As shown in FIG. 8A, in the portable cutting tool 1, when the cutting operation further proceeds and the cutting depth of the rotary blade 9 becomes full, the guide portion 11f of the protective cover body 11 is placed on the surface of the workpiece W. The cutting operation is performed from the bottom to the top by using the surface as a guide surface. When the portable cutting tool 1 is moved above the member to be cut W by an operator, for example, if a marking line is formed, the member support part 12 provided in the notch part 11g of the protective cover body 11 is used. The cutting edge of the rotary blade 9 exposed from the dust-proof member 13 is in a state where it can be seen. Therefore, the operator can move the portable cutting tool 1 upward in a state where the cutting edge of the rotary blade 9 and the marking line are visually recognized. Even when the operator's head approaches the tool side when recognizing the cutting edge of the rotary blade 9, the dustproof member 13 is at the position of the notch 11g, so that most of the dust comes out of the notch 11g. Because there is no, you can work safely.

  As shown in FIG. 8B, in the portable cutting tool 1, when the cutting operation is performed in a state where the guide portion 11f is in contact with the surface of the workpiece W, the cutting according to the cutting depth of the rotary blade 9 is performed. A groove Wm is formed, and dust tends to scatter along the cut groove Wm. At this time, in the portable cutting tool 1, the air from the blowout hole 16a of the dust collecting portion 14 becomes an air curtain in the cut groove Wm. Therefore, in the portable cutting tool 1, even if the kerf Wm is formed, the generated dust can be collected from the one end opening 15c of the cylindrical main body portion 15 in the dust collecting portion 14 by the air curtain. In particular, in the portable cutting tool 1, the position of the blowout hole 16a blows air into the cut groove Wm, that is, the position corresponding to the rotary blade 9 (on the extension line of the rotary blade 9 or the side plates 11a and 11b). 90% or more of the generated dust can be recovered.

As shown in FIG. 8B, in the portable cutting tool 1, dust generated in the dust collection bag Sb is collected via the dust collection hose Sh, and the air used for collecting the dust is collected in the dust collection bag Sb. Since it is a member which allows air to pass through, such as a nonwoven fabric, it is put out outside.
As described above, the portable cutting tool 1 performs the cutting operation by rotating the rotary blade 9 with the air of the compressor CP even in a site where there is no electrical equipment, and the dust collection unit 14 receives air from the compressor CP. By being supplied via the air branch hose 20, an air curtain and an air flow for collecting dust are formed, so that generated dust can be efficiently collected.

  The portable cutting tool 1 may change the configuration of the air branch hose 20. That is, since the portable cutting tool 1 is configured to form an air flow for collecting air by branching the air sent from the compressor CP, the air sent to the drive turbine 5 side of the main body 2. The air amount is adjusted in advance by an air adjusting screw 22a (see FIG. 3). And the air from the air branch hose 20 is used so that the air from which directions differ in the 1st air blowing part 16 and the 2nd air blowing part 17 may flow out. Therefore, as shown in FIG. 9 and FIG. 10, the portable cutting tool 1 </ b> A will be described as more preferably having a configuration for adjusting the output in the branched air. In FIG. 9 and FIG. 10, the already described configurations are denoted by the same reference numerals and description thereof is omitted.

  As shown in FIG. 9, in the air branch hose 20 </ b> A, the one end side connection portion 22 has the same configuration as that already described, but the configuration on the other end side is different. That is, in the air branch hose 20A, the branch hose 21a is further branched by the branch pipe 21b on the other end side, and the first other end side connection portion 23a and the branch pipe 21b are connected via the first hose 21d and the second hose 21e. The second end side connection part 23b is connected to the hose connection parts 14a and 14a provided in the dust collection part 14, respectively. And the air branch hose 20A is provided with the adjustment part 21c in the branch pipe 21b. This adjustment part 21c can adjust the supply amount of air by adjusting the opening degree of a flow path by rotating a screw part. Therefore, the portable cutting tool 1A can adjust the flow rate of air when branching from the air supply hose Ah in the air branch hose 20A, and further, the flow rate of air when sending the branched air to the dust collecting portion 14 can be adjusted. Adjustment can be performed, and operation more suitable for the tool environment can be realized.

  Further, as shown in FIG. 10, the dust collecting portion 14 </ b> A may have a configuration in which an adjustment pin 32 is provided so that the blowout hole 16 a formed in the one side closed end surface 16 b of the cylindrical main body portion 15 can be opened and closed. The adjustment pin 32 is configured such that a pin shaft portion 32a is disposed orthogonal to the hole length direction of the blow hole 16a, and the opening degree of the blow hole 16a can be adjusted by an adjustment hole 32b formed in the pin shaft portion 32a. Has been. That is, when the positions of the adjustment hole 32b and the blowout hole 16a coincide, the opening degree of the blowout hole 16a becomes 100%. The adjustment pin 32 can adjust the amount of air blown from the blowout hole 16a by the operator appropriately operating with fingers.

The shape of the cylindrical main body portion 15 has been described as an example in which the cylindrical main body portion 15 is formed in a cylindrical shape having the opening groove 15a in the axial direction, but the shape may be any cylindrical shape having the opening groove 15a.
Further, the flow path 15b formed inside the cylindrical main body portion 15 in the plate thickness direction has been described as the entire space between the plates. However, the pores are formed inside the plate thickness direction by a drill or the like, and the pores are formed. The flow path 15b may be used.

  Moreover, in the dust collection part 14, although the 1st air blowing part 16 is set as the structure which formed the blowing hole 16a in the one side obstruction | occlusion end surface 16b of the cylindrical main-body part 15, it is air to the groove Wm formed by the rotary blade 9. Any position may be used as long as the first air blowing portion 16 can be blown out. For example, as shown in FIGS. 11A and 11B, a small L-shaped tube is formed on the cylindrical inner peripheral surface 15d of the cylindrical main body 15 or the cylindrical outer peripheral surface (or a cylindrical inner peripheral surface indicated by a virtual line). It is good also as a structure which protrudes and provides the blower hole (air outlet) 36a, and supplies air from the 2nd hose 21e. As shown in FIG. 11A, the air blowing angle θ1 blown out from the blowing hole 36a (same as the blowing hole 16a shown in FIGS. 1 to 8) is an angle (0 degrees) orthogonal to the guide portion 11f. It is preferable that the air is blown out in such a manner that the air blowing angle θ1 does not exceed 30 degrees.

  The blow angle θ1 is also set in relation to the attachment angle θ2 of the protective cover 11 of the dust collecting portion 14, but ultimately, the blow angle θ1 is given priority and is within the above-described range. Good. When the blowing angle θ1 is greater than 30 degrees, there is a high possibility that dust generated by the rotary blade 9 enters through the opening of the protective cover body 11 and the dust collection work cannot be performed more efficiently than originally planned. Note that the blowout angle θ1 can serve as an air curtain even if it is 10 degrees from 0 degrees to the minus side. However, if the outlet angle exceeds 10 degrees on the minus side, the role of increasing dust collection efficiency as an air curtain cannot be achieved. Therefore, the blow angle θ1 is a maximum allowable range of 30 ° to −10 °, practically a range of 20 ° to −5 °, and a more preferable range is 15 ° to −3 °. Range.

  And although the blowing hole 16a was demonstrated as an example formed in one place, as shown in FIG. 12 (a), (b), the formation place becomes below the center of the circular arc of the cylindrical main-body part 15. As shown in FIG. There may be a plurality of locations (2 locations, 3 locations, 4 locations or more). When a plurality of outlet holes 36a are installed around the outer periphery of the cylindrical main body 15 (in the case of FIG. 12B), air is supplied to each outlet hole 36a by the flow path 36b connecting the outlet holes 36a. It is set as the structure supplied to. In addition, it is desirable that the position where the blowout hole 16a is formed is a position facing the rotary blade 9 and a position along the one end opening 15c of the cylindrical main body portion 15. Further, the shape of the blowout holes 16a, 36a or the dust collection blowout holes 17a is not limited to one or a plurality, but is shown as a round hole shape, but it follows the edge shape that is one end opening or the other end opening of the cylindrical main body portion 15. It may be formed in a slit shape. The blow-off angle θ1 is the same as that described above even when there are a plurality of blow-out holes 16a and 36a.

  Furthermore, in the dust collection part 14, although the 2nd air blowing part 17 demonstrated as a structure which formed multiple dust collection blowing holes 17a in the other side obstruction | occlusion end surface 17b of the cylindrical main-body part 15, the air of the air which goes to dust collection hose Sh Any position and number that can form a flow may be used. For example, a dust collection outlet 17a (not shown) may be formed obliquely on the cylinder inner peripheral surface 15d of the cylindrical main body 15 so as to go to the other end opening 15e side of the cylindrical main body 15. .

  The cylindrical main body portion 15 has been described as a configuration in which the air flow path 15b to the first air blowing portion 16 and the second air blowing portion 17 is shared, but the air flows from the center of the cylindrical main body portion 15 to the left and right. Alternatively, the flow paths may be separated. That is, the inside of the cylindrical main body 15 is divided into two parts, and air may be supplied to each of the divided one and the other by the first hose 21d and the second hose 21e as shown in FIG. Absent. In this way, the amount of air blown from the first air blowing portion 16 and the second air blowing portion 17 by supplying air to the independent flow path between the first air blowing portion 16 and the second air blowing portion 17. This is easier and more convenient.

Moreover, as shown in FIG.13 and FIG.14, it is good also as a structure of the cylindrical main-body part 150. FIG. That is, it is desirable that the cylindrical main body 150 is configured to have a relationship of φ1 ≧ φ2 with respect to the dimension of the inner peripheral diameter (inner diameter) φ1 and the inner peripheral diameter (inner diameter) φ2 of the connecting pipe 19. . That is, in the cylindrical main body 150, the inner diameter φ1 with respect to the inner diameter φ2 of the connection pipe 19 is formed by increasing the width of the flow path 150b in the inner peripheral direction and reducing the diameter of the inner peripheral surface 150d. Are configured so as to satisfy the relationship of φ1 ≧ φ2.
The cylindrical main body 150 is basically the same as the configuration already described with reference to FIG. 5, and the inner tube and the outer tube, one side installed on one side and the other side in the state where the opening groove 150 a is formed. A space surrounded by the closed end face 160b and the other closed end face 170b is defined as a flow path 150b, and one end and the other end of the cylinder inner peripheral face 150d are configured as one end opening 150c and the other end opening 150e.

  Hereinafter, the case 1 will be described as a specific example in which the inner peripheral diameter φ2 of the connecting pipe 19 is φ1> φ2. In the case of the case 1, the wind pressure and the suction force were measured in a state in which the dimension of the inner peripheral diameter φ1 of the cylindrical main body 150 was 35 mm and the dimension of the inner diameter φ2 of the connecting pipe 19 was 38 mm to 32 mm. In the following description, the wind pressure and the suction force were measured as a height value of the liquid in the measurement hose using a manometer.

  As a measuring method, a measuring hose is connected to a connecting pipe, a part of the measuring hose is U-shaped, and a liquid (water) is put into the measuring hose of the U-shaped part, and the U-shaped part U The value (mm) of the difference in liquid height between one vertical portion and the other vertical portion of the character portion was defined as the wind pressure. In the case 1 described above, the wind pressure was 304 mm, and in the case of φ1 <φ2, the size of φ1 was 35 mm, and the wind pressure was 1.3 times that of 234 mm when φ2 was 38 mm.

  Further, the suction force is measured by connecting a measuring hose to the one end opening 150c side of the cylindrical main body 150 and measuring a portion of the U-shaped portion in the same manner as the measuring method described above. Was measured as the difference between the height of one of the vertical portions and the height of the other vertical portion. In the case of case 1, the difference in height was −170 mm, which was the suction force. In the case of φ1 <φ2, the suction force was 1.3 times that of the suction force of −125 mm when the size of φ1 was 35 mm and φ2 was 38 mm.

Next, in the case of the case 2, the measurement method described above in the state where the dimension of the inner diameter φ1 of the cylindrical main body 150 is 32 mm and the dimension of the inner diameter φ2 of the connection pipe 19 is 32 mm so that φ1 = φ2. The wind pressure and suction force were measured at In the case 2, the wind pressure and the suction force are values of 368 mm and −218 mm, respectively. When φ1 <φ2, the size of φ2 is 38 mm, and φ1 is 35 times 1.6 times and 1.7 times. It became each.
In this way, the cylindrical main body 150 has an inner diameter relationship with the connecting pipe 19 of φ1 ≧ φ2 so that the wind pressure and the suction force are improved, so that the dust generated during the operation can be more reliably collected. Is possible.

  Further, as shown in FIGS. 15A and 15B, the center of the dust collection outlet 170a in the other closed end face 170b of the second air outlet 170 is the center line in the end face width direction of the other closed end face 170b. It is desirable that the dust collection outlets 170a be formed so as to be eccentric from the inner diameter side (cylinder inner peripheral surface side) of Tc. When the supplied air is from the compressor, the dust collection outlet 170a contains moisture in the air. Therefore, dust collected by blowing out air accumulates around the hole and deposits AN Will adhere. Therefore, when the dust collection outlet 170a is arranged on the cylinder inner peripheral surface 150d side, as shown in FIGS. 15B and 15C, a part ANp on the inner diameter side of the dust deposit AN is in the cylinder. It can be deposited so as to protrude from the peripheral surface 150d.

  As described above, the cylindrical main body 150 causes the part ANp of the deposit AN to protrude toward the cylinder inner peripheral surface 150d side depending on the position of the dust collection outlet 170a, so that the air flowing along the cylinder inner peripheral surface 150d. Will hit part of the ANp, and the deposit AN can be peeled off from the dust collection outlet 170a by the flow of air. Since most of the deposit AN is deposited like a cone around the dust collection outlet hole 170a, the dust collection outlet hole 170a is formed at a position close to the cylinder inner peripheral surface 150d side. A part of the ANp always protrudes toward the cylinder inner peripheral surface 150d side and is peeled off by the air flow.

Therefore, the worker does not clog the dust collection outlet hole 170a due to the dust deposit AN during the work, and can perform the work without changing the suction force in a series of work.
The position of the dust collection outlet 170a may be formed so as to be closer to the inner diameter side than the center line of the other closed end face 17b, even in the configuration shown in FIG. 5 as described above. Of course not.

Furthermore, still another configuration of the first air blowing portion and the second air blowing portion for the portable cutting tools 1 and 1A will be described with reference to FIGS. 16 and 17. In addition, the already demonstrated structure attaches | subjects the same code | symbol and abbreviate | omits description.
As shown to FIG. 16 (a), (b), it is set as the structure which provided here the blowing nozzle 160A in the lower end side of 150 A of cylindrical main bodies as a 1st air blowing part. The cylindrical main body 150A has a structure in which the flow path 15b (see FIG. 3) is not formed in the plate thickness direction, and is configured, for example, as a state in which a metal plate is processed into a cylindrical shape.

  The blow nozzle 160A is connected to the second hose 21e and blows air from the air branch hose 20A from the blow hole 160Aa at the tip to the member W to be cut, and is a coil spring that is an elastic member by the nozzle support portion 161. It is supported by the cylindrical main body 150 </ b> A via 162.

  Here, the blowout nozzle 160A includes a cylindrical portion 160Ab made of metal and formed in a cylindrical shape, and a flange 160Ac provided on the front end side of the cylindrical portion 160Ab, and an air branch is formed on the rear end side of the cylindrical portion 160Ab. The second hose 21e of the hose 20A is configured to be detachable. The shape and the position of the nozzle support part 161 are not limited as long as the nozzle support part 161 can support the blowing nozzle 160A on the cylindrical main body part 150A. In addition, the coil spring 162 supports both ends inside the flange 160Ac and the nozzle support portion 161 of the blowing nozzle 160A so that the tip of the blowing nozzle 160A protrudes from the nozzle support portion 161.

  The blowing nozzle 160A is supported by the nozzle support part 161 so as to always protrude from one end of the cylindrical main body part 150A to the workpiece W side by a coil spring 162. Here, for example, as the protrusion amount dm, 2 to It protrudes within a range of 10 mm (preferably 3 to 5 mm). The blowout nozzle 160A is biased toward the member to be cut W so that when the cutting operation is performed, the blowout nozzle 160A enters the cut groove Wm (see FIG. 8B) formed by the cutting operation. Air is blown out to form an air curtain. Therefore, the blowout nozzle 160A further improves the effectiveness of the air curtain to be formed, and the nozzle tip side enters the kerf Wm and serves as a guide along the kerf Wm when moving together with the tool in the cutting direction. Can also fulfill.

  Further, as shown in FIGS. 16C, 17A, and 17B, an air nozzle 170A as a second air blowing portion may be provided facing the inner peripheral side of the cylindrical main body 150A. Absent. In the air nozzle 170A, here, a dust collection outlet 170Aa that blows out air formed at one end of the nozzle is disposed at a position that is substantially at the center of the cylindrical main body 150A. Further, the position of the air nozzle 170A in the axial direction of the cylindrical main body 150A is such that the dust collection outlet 170Aa is disposed at the same position as the other end opening 15e of the cylindrical main body 150A. The air nozzle 170A is provided on the side surface of the cylindrical main body 150A via the air nozzle support 171. The air nozzle 170A collects air from the first hose 21d detachably connected to the air nozzle support 171 through the dust collection outlet 170Aa. Is blowing out.

  Note that the position of the dust collection outlet 170Aa on the inner peripheral side of the cylindrical main body 150A is not particularly limited as long as it can form a flow of airflow for collecting dust. . Further, the diameter of the dust collection outlets 170Aa is formed to be equal to or greater than the diameter of the total area of the dust collection outlets 17a formed at the six locations shown in FIG. Incidentally, the diameter of the dust collection outlet 170Aa is 1/15 to 1 with respect to the diameter in the pseudo inner peripheral area of the cylindrical main body 150A (the inner peripheral surface area by a circle when the opening groove 15a is not provided). A range of / 5 is preferable.

  As shown in FIG. 17A, the air nozzle 170A is arranged on the inner peripheral side of the cylindrical main body 150A, so that when the air is blown out from the dust collection blowing hole 170Aa, the workpiece W is cut by the rotary blade 9. In this case, dust is efficiently collected from the opening groove 15a and the one end opening 15c, so that an air flow toward the other end opening 15e is formed. Further, by adopting the configuration of the air nozzle 170A, the flow of the airflow passes through the periphery of the dust collection outlet hole 170Aa, and the airflow that has passed around the dust collection outlet hole 170Aa is in the vicinity of the dust collection outlet hole 170Aa. Swirl is unlikely to occur and dust does not adhere to the nozzle portion near the dust collection outlet 170Aa.

  Further, the one end opening side in the cylindrical main body portions 15, 150, etc. in FIGS. 1 to 17 is formed on the inside or outside of the one side closed end face, the blowout holes 16a, 160a, 160Aa formed on the one side closed end face. The state of the blowout holes 36a (see FIGS. 11 and 12), that is, any of the blowout holes 16a, 36a, 160a, 160Aa formed on the inner side, the surface side, and the outer side of the one-side closed end surface may be used. Absent. Similarly, the other end opening side may be the inner side, the surface side, or the outer side of the other closed end surface. As a better configuration on the other end opening side, a configuration in which the dust collection outlet 170a is arranged on the inner diameter side from the center line Tc of the other closed end surface already shown in FIG. 15, or the air nozzle shown in FIG. The configuration is such that 170A is arranged facing the inner peripheral side of the cylindrical main body 150A.

Moreover, although the member support part 12 (refer FIG. 1) was demonstrated as an example which is a U-shaped metal plate piece, it is comprised so that a rectangular metal plate piece can be fixed to a right and left with a screw, respectively, etc. If 13 can be installed in the state adjacent to the rotary blade 9, it will not be limited.
Furthermore, although the dustproof member 13 has been described as being configured to be adjacent to the rotary blade 9, the dustproof member 13 may be in contact with the rotary blade 9. That is, in the range of the notch portion 11g, when the rotary blade 9 rotates in a state where the dustproof member 13 is installed in contact with the rotary blade 9, the dustproof member 13 is scraped by the cutting edge and is substantially adjacent to each other. Become.

The protective cover body 11 and the dust collecting portion 14 have been described as an example formed of a metal material. However, the protective cover body 11 and the dust collecting portion 14 may be resin, and if the resin is used, cutting is performed while confirming the state of dust collection by using a transparent material. Work can be performed.
Note that the bush 9b may not be provided as a configuration for supporting the rotary blade 9 on the drive shaft 6, and any known mechanism may be used as long as the rotary blade 9 is detachably supported on the drive shaft 6.

  Further, as shown in FIGS. 18A to 18C, the shapes of the lower ends of the cylindrical main body portions 15, 150, 150A and the nozzle support portion 161 can be brought into contact with the surface of the member to be cut W. It is more preferable that the structure is formed flat. As shown in FIG. 18A, when the shapes of the lower ends of the cylindrical main body portions 15, 150, 150A and the nozzle support portion 161 are flat, as shown in FIG. In this case, there is no gap when the flat part at the lower end of the cylindrical main body parts 15 and 150 or the flat part of the nozzle support part 161 and the surface of the workpiece W are in contact with each other. It becomes possible to improve. In addition, when forming the shape of the lower end side of the nozzle support part 161 flat, it is preferable to comprise the horizontal width according to the cylinder width of 150 A of cylindrical main-body parts.

  At the lower end side of the cylindrical main body portions 15, 150, 150A or the nozzle support portion 161, one end opening side of the cylindrical main body portions 15, 150, 150A is formed so as to be in contact with the surface of the member W to be cut. It is sufficient that the lower end side is flat across the opening at the other end, but the whole is not necessarily flat. That is, in the cylindrical main body portions 15, 150, 150A, one end opening portion on the lower end side is formed flat so as to abut in parallel to the surface of the member W to be cut, and the other end opening portion is formed in a cylindrical shape. It doesn't matter. In addition, if the lower end side of the one end opening portion of the cylindrical main body portions 15, 150, 150A can abut in parallel with the surface of the member W to be cut, one side is attached to the cylindrical main body portion and the other side is covered. You may make it attach the separate member currently formed in contact with the cutting member W flat. Of course, when it is attached as a separate member, it may be detachable from the cylindrical main body parts 15, 150, 150A, or may be fixed by screws or the like. Furthermore, when the part that abuts in parallel with the surface of the member W to be cut is a separate member, the material may be a resin different from the cylindrical main body portions 15, 150, and 150A by resin or the like.

DESCRIPTION OF SYMBOLS 1, 1A Portable cutting tool 2 Main body part 3 Hose connection part 4 Air flow path 5 Drive turbine 6 Drive shaft 7 Support part 8 Release | release part 9 Rotary blade 9A Mounting member 9a Wheel washer 9b Bush 9c Nut 9d Bolt 10 Dust collection structure DESCRIPTION OF SYMBOLS 11 Protective cover body 11a Side plate 11b Side plate 11c Peripheral plate 11d Mounting hole 11e Mounting part 11f Guide part 11g Notch part 11e ₁ fixing | fixed part 11e ₂ separation | separation part 12 Member support part 12a Fixing plate piece 12b Supporting plate piece 13 Dust-proof member 14, 14A Dust collection part 14a Hose connection part 15 Cylindrical body part 15a Opening groove 15b Flow path 15c One end opening 15d Inner cylinder peripheral surface 15e Other end opening 16 First air blowing part 16a Blowing hole 16b One side closed end face 17 Second air blowing Part 17a Dust collection outlet 17b Other side closed end face 18 Cylindrical taper part 19 Connection pipe 0, 20A Air branch hose 21 Hose body 21a Branch hose 21b Branch pipe 21c Adjustment part 21d First hose 21e Second hose 22 One end side connection part 22a Air adjustment screw 23 Other end side connection part 23a First other end side connection part 23b 2nd other end side connection part 25 Connection interposition part 26 Interposition part main body 27 Supply hose connection part 28 Tool side connection part 29 Branch hose connection part 30 Inscribed member 32 Adjustment pin 32a Pin shaft part 32b Adjustment hole Ah Air supply hose CP Compressor L1 Vertical line Sh Dust collection hose Sb Dust collection bag W Material to be cut Wm Groove

Claims (12)

An air supply hose for supplying air is connected, and a main body having a drive turbine that is rotated by the air, and a disk-shaped rotary blade attached to a drive shaft that is rotated by the drive turbine of the main body is used as a workpiece. A portable cutting device for collecting the dust generated when cutting, and cutting the member to be cut while collecting the dust through a dust collecting hose connected to the dust collecting structure. In the tool
The dust collection structure is provided over a predetermined angular range of the rotary blade so as to expose a predetermined arc range of the rotary blade, and an arc covering the cutting edge and the left and right side surfaces of the rotary blade other than the exposed A protective cover body in shape,
A dust collecting portion provided on one end side of the arc shape of the protective cover body;
An air branch hose branched from the air flow path supplied by the air supply hose and connected to the dust collecting part,
The dust collecting portion includes a cylindrical main body portion having an opening groove formed between the left and right side surfaces of the protective cover body, and air supplied from the one end opening side of the cylindrical main body portion by the air branch hose. A first air blowing portion that blows out air, and a second air blowing portion that blows out air supplied from the other end opening side of the cylindrical main body portion by the air branch hose,
The cylindrical main body is formed with a flow path in the plate thickness direction, and the air from the air branch hose is supplied to the first air blowing part and the second air blowing part through the flow path,
The first air blowing part is formed with a blowing hole for blowing out the air supplied from the air branch hose at the position of the one-side closed end surface of the cylindrical main body part that is in a range facing the opening groove.
The second air blowing portion is formed with a dust collection blowing hole for blowing air supplied from the air branch hose on the inner circumferential side surface of the cylindrical main body portion or the other closed end surface of the cylindrical main body portion . A portable cutting tool characterized by that. The second air blowing part is an air nozzle that faces the inner peripheral side of the cylindrical main body part, is supported by the cylindrical main body part, and directs the dust collection blowing hole in the direction of blowing air to the other end opening side. Yes,
The portable cutting tool according to claim 1, wherein the air branch hose is connected to supply air from the air branch hose to the air nozzle.   The protective cover body has an opening end portion that exposes the rotary blade and abuts when the rotary blade is cut into the member to be cut. Linearly so that a part of the cutting edge of the rotary blade is exposed from the protective cover body when the guide part comes into contact with the member to be cut. The portable cutting tool according to claim 1, further comprising a notch portion formed by notching an end side of the typical guide portion. The cutout portion is interposed between the rotary blade and the protective cover body in the range of the cutout portion, and is provided with a dustproof member toward the rotary blade, and the dustproof member is in the range of the cutout portion. The portable cutting tool according to claim 3 , wherein the portable cutting tool is installed adjacent to the rotary blade.   The dust collecting portion is provided with a cylindrical tapered portion having a tapered inner peripheral surface in which a space gradually narrows from the other closed end surface of the cylindrical main body portion continuously to the other closed end surface of the cylindrical main body portion. The portable cutting tool according to claim 1.   A connection interposition part for connecting the air branch hose is provided between the main body part and the air supply hose, and the air branch hose is connected to the connection interposition part and the cylindrical main body part. The portable cutting tool according to claim 1, wherein The protective cover body has a brush-shaped inscribed member provided in a line so as to contact the substrate of the rotary blade between the drive shaft side and the blade edge side of the rotary blade inside. The portable cutting tool according to any one of claims 1 to 6, wherein the portable cutting tool is characterized.   The cylindrical main body is provided with a connecting pipe for connecting the dust collecting hose so as to protrude in the cylinder axial direction from the outer peripheral side of the cylinder at the other end opening, and the inner peripheral diameter of the cylindrical main body is The portable cutting tool according to any one of claims 1 to 7, wherein the portable cutting tool is formed to have a diameter larger than or equal to an inner diameter of the connection pipe. The cylindrical main body portion is formed with a dust collection blowing hole of the second air blowing portion on the inner diameter side from the center on the other closed end surface forming the second air blowing portion, which is the other end opening side. The portable cutting tool according to claim 1 . A disk-shaped rotary blade attached to a drive shaft is rotated by air supplied from an air supply hose and is detachably attached to a support portion around the drive shaft of a portable cutting tool that cuts a workpiece. A dust collection structure to be used,
An arc-shaped protective cover body that is provided over a predetermined angular range of the rotary blade so as to expose a predetermined arc range of the rotary blade, and covers a blade tip and left and right side surfaces of the rotary blade other than the exposed blade,
A dust collecting portion provided on one end side of the arc shape of the protective cover body;
An air branch hose branched from the air flow path supplied by the air supply hose and connected to the dust collecting part,
The dust collecting portion includes a cylindrical main body portion having an opening groove formed between the left and right side surfaces of the protective cover body, and air supplied from the one end opening side of the cylindrical main body portion by the air branch hose. A first air blowing portion that blows out air, and a second air blowing portion that blows out air supplied from the other end opening side of the cylindrical main body portion by the air branch hose,
The cylindrical main body is formed with a flow path in the plate thickness direction, and the air from the air branch hose is supplied to the first air blowing part and the second air blowing part through the flow path,
The first air blowing part is formed with the blowing hole for blowing the air supplied from the air branch hose at a position of one side closed end surface of the cylindrical main body part in a range facing the opening groove,
The second air blowing portion is formed with a dust collection blowing hole for blowing air supplied from the air branch hose on the inner circumferential side surface of the cylindrical main body portion or the other closed end surface of the cylindrical main body portion . A dust collection structure characterized by that.   The cylindrical main body is provided with a connecting pipe for connecting a dust collection hose for dust collection so as to protrude in the cylinder axial direction from the outer peripheral side of the cylinder at the other end opening, and the inner periphery of the cylindrical main body 11. The dust collecting structure according to claim 10, wherein the diameter is larger than or equal to the inner diameter of the connection pipe.   The cylindrical main body portion is formed with a dust collection blowing hole of the second air blowing portion on the inner diameter side from the center on the other closed end surface forming the second air blowing portion, which is the other end opening side. The dust collection structure according to claim 11.

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