Work machine

Abstract

The present invention provides a work machine that suitably collects machining chips such as dust generated during work. In a circular saw (10), a chip discharge port (27H) and a hood opening (27J) are formed in an inner hood (27), and a dust collection chamber inlet portion (62L1) and a dust collection chamber outlet portion (62L2) are formed in a dust collection housing (60). Moreover, at least a part of the dust collection chamber inlet portion (62L1) and at least a part of the dust collection chamber outlet portion (62L2) are arranged at the same position in the vertical direction.

Description

Technical Field

[0001] The present invention relates to a working machine. Background Art

[0002] The portable circular saw (working machine) described in Patent Document 1 below has a dust box, and chips generated during work are collected in the dust box. Specifically, the dust box has an opening, and the chips rolled up by the rotation of the circular saw flow into the dust box through the opening. Thus, during cutting work, the chips can be collected in the dust box.

[0003] Prior Art Documents

[0004] Patent Documents

[0005] Patent Document 1: Japanese Patent Application Laid-Open No. 2011-68073 Summary of the Invention

[0006] Problems to be Solved by the Invention

[0007] However, in the portable circular saw, there is room for improvement in the following aspects. That is, in the portable circular saw, when cutting a workpiece, an air flow is generated due to the rotational force of the circular saw, and the chips and air flow into the dust box together.

[0008] Here, in the portable circular saw, since air continuously flows into the dust box during cutting work, the pressure in the dust box rises, and there is a possibility that the dust collection efficiency of the dust box decreases.

[0009] In view of the above fact, an object of the present invention is to provide a working machine capable of appropriately collecting processing pieces such as dust generated during work.

[0010] Technical Means for Solving the Problems

[0011] One or more embodiments of the present invention are a work machine, including: a base formed in a plate shape; a housing supported on one side in the plate thickness direction of the base, accommodating a motor for driving a tip tool, and including a cover member covering the tip tool; and a dust collector housing fixed to the housing, having a dust collection chamber capable of collecting machining chips generated by driving the tip tool. A first opening for transporting the machining chips to the dust collection chamber and a second opening for transporting the air in the dust collection chamber to the inside of the cover member are provided in the cover member. In the dust collector housing, an inlet for transporting the machining chips transported from the first opening to the dust collection chamber, a flow-in portion connecting the inlet and the first opening, an outlet for transporting the air in the dust collection chamber to the second opening, a flow-out portion connecting the outlet and the second opening, and a partition portion dividing the dust collection chamber from the flow-in portion and the flow-out portion are provided. In the plate thickness direction of the base, at least a part of the inlet and at least a part of the outlet are arranged at the same position.

[0012] One or more embodiments of the present invention are a work machine, wherein a through hole for allowing a part of the tip tool to protrude to the other side in the plate thickness direction of the base is formed in the base, and an adjustment mechanism capable of adjusting the protruding amount of the tip tool from the through hole is connected to the housing. At least when the protruding amount of the tip tool is the largest, at least a part of the inlet and at least a part of the outlet are arranged at the same position in the plate thickness direction of the base.

[0013] One or more embodiments of the present invention are a work machine, wherein the tip tool is a circular saw blade in a circular plate shape, and the cover member covers the circular saw blade from one side in the plate thickness direction of the base.

[0014] One or more embodiments of the present invention are a work machine, wherein the inlet and the outlet are arranged side by side in the plate thickness direction of the circular saw blade.

[0015] One or more embodiments of the present invention are a work machine, wherein the first opening is arranged on the upstream side in the rotation direction of the circular saw blade relative to the second opening.

[0016] One or more embodiments of the present invention are a work machine, wherein the second opening is composed of a plurality of holes.

[0017] One or more embodiments of the present invention are a work machine, wherein the area of the inlet is 80% - 120% of the area of the outlet.

[0018] One or more embodiments of the present invention are a work machine, wherein a partition wall that divides the inflow portion and the outflow portion is provided in the dust collection housing.

[0019] One or more embodiments of the present invention are a work machine, wherein a guide portion that divides the inflow portion and the outflow portion in a direction different from the partition wall is provided in the dust collection housing.

[0020] One or more embodiments of the present invention are a work machine, wherein chips or air discharged from the inlet portion to the dust collection chamber are guided away from the outlet portion by the guide portion. One or more embodiments of the present invention are a work machine, wherein due to the guide portion, the flow path area of the inflow portion decreases as it approaches the inlet portion side. One or more embodiments of the present invention are a work machine, wherein the dust collection chamber has an upper housing wall, a bottom housing wall, and a side housing wall that connects the upper housing wall and the bottom housing wall, and at least one of the inlet portion and the outlet portion is adjacent to the upper housing wall.

[0021] One or more embodiments of the present invention are a work machine that performs a machining operation in the forward direction, and the work machine has a dust collection structure that collects dust generated by the machining operation. The dust collection structure includes: a dust collection chamber that stores dust; a transfer portion that includes an inflow portion that conveys dust to the storage portion and an outflow portion that discharges air in the dust collection chamber to the outside of the dust collection structure; a first partition portion that extends upward while being connected to the lower portion of the dust collection chamber to divide the dust collection chamber and the transfer portion; and a communication portion that is located above the upper end of the first partition portion and communicates the dust collection chamber and the transfer portion. In the work machine, an inlet portion connected to the inflow portion and an outlet portion connected to the outflow portion are provided in the communication portion, and the positions of one ends of the inlet portion and the outlet portion in the left-right direction are different. One or more embodiments of the present invention are a work machine configured such that at least a part of the inlet portion and the outlet portion are in different positions in the left-right direction or in the same position in the up-down direction. One or more embodiments of the present invention are a work machine, wherein in the transfer portion, a second partition portion that divides the inflow portion and the outflow portion in the front-rear direction and a third partition portion that divides the inflow portion and the outflow portion in the left-right direction are provided.

[0022] One or more embodiments of the present invention are a work machine, including: a base formed in a plate shape; a housing supported on one side in the plate thickness direction of the base, accommodating a motor for driving a tip tool, and including a cover member covering the tip tool; a first opening and a second opening formed in the cover member, configured such that processing pieces generated during driving of the tip tool can pass through; and a dust collector provided in the cover member for collecting the processing pieces, the dust collector including the following members: a first discharge path connected to the first opening, together with the first opening, constituting a first dust collection path that communicates the inside of the cover member with the outside of the dust collector, and discharging the processing pieces that have passed through the first opening to the outside; and a second discharge path connected to the second opening and the first discharge path, together with the second opening, constituting a second dust collection path that communicates the inside of the cover member with the first discharge path, and discharging the processing pieces that have passed through the second opening to the first discharge path, and the minimum flow path area of the second dust collection path is set to be equal to or less than the minimum flow path area of the first dust collection path.

[0023] Effects of the Invention

[0024] According to one or more embodiments of the present invention, it is possible to appropriately collect processing pieces such as dust generated during operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a perspective view of the circular saw according to the present embodiment as viewed from the upper right front.

[0026] Figure 2 is Figure 1 A side view of the circular saw shown as viewed from the right side.

[0027] Figure 3 is Figure 1 A side view of the circular saw shown as viewed from the left side.

[0028] Figure 4 is showing Figure 1 A perspective view of the tool body of the circular saw shown as viewed from the upper right front.

[0029] Figure 5 is showing Figure 3 A cross-sectional view of the inside of the tool body shown as viewed from the upper side ([[: Figure 3 Cross-sectional view taken along line 5-5).

[0030] Figure 6 is showing Figure 5 A partially cut-away perspective view of the adjustment mechanism shown as viewed from the lower left rear.

[0031] Figure 7 It shows Figure 2 a cross-sectional view of the inside of the dust collection housing in the initial state of the circular saw shown, as viewed from the right side.

[0032] Figure 8 It is a view that Figure 7 magnifies and shows a cross-sectional view of the front part of the dust collection housing shown.

[0033] Figure 9 It shows Figure 7 a cross-sectional view of the inside of the dust collection housing in the minimum protrusion state of the circular saw shown, as viewed from the right side.

[0034] Figure 10 It shows in the state of removing the housing member on the right side of the housing main body Figure 1 a perspective view of the dust collection housing shown, as viewed from the right rear.

[0035] Figure 11 It shows Figure 1 a partially cut-away perspective view of the inside of the front part of the dust collection housing shown.

[0036] Figure 12 It shows Figure 7 a cross-sectional view of the middle part in the front-rear direction of the dust collection housing shown, as viewed from the rear side ( Figure 7 sectional view taken along line 12 - 12 of

[0037] Figure 13 It shows Figure 8 a cross-sectional view of the front part of the dust collection housing shown, as viewed from the front side ( Figure 8 sectional view taken along line 13 - 13 of

[0038] Figure 14 a view showing the inflow part, outflow part, and storage part of the dust collection structure in the present invention.

[0039] Figure 15 It shows a state where Figure 2 instead of the dust collection housing shown, a dust collection adapter is installed on the tool main body, as viewed from the right side.

[0040] Figure 16 It shows Figure 15 a cross-sectional view of the inside of the dust collection adapter in the initial state of the circular saw shown, as viewed from the right side.

[0041] [Explanation of reference signs]

[0042] 10: Circular saw (working machine)

[0043] 12: Circular saw blade (tip tool)

[0044] 22: Base

[0045] 22B: Tool insertion part (through hole)

[0046] 25A: Saw cover part (cover member)

[0047] 27: Inner cover (cover member)

[0048] 27H: Chip discharge port (first opening part)

[0049] 27J: Cover opening part (second opening part)

[0050] 27J1: Opening hole part (hole)

[0051] 33: Adjustment mechanism

[0052] 47: Motor

[0053] 60: Dust collector housing

[0054] 62A: Housing bottom wall

[0055] 62B: Housing right wall (housing side wall)

[0056] 62C: Housing left wall (housing side wall)

[0057] 62D: Housing upper wall

[0058] 62L1: Dust collection chamber inlet part (inlet part)

[0059] 62L2: Dust collection chamber outlet part (outlet part)

[0060] 62P: Guide wall (guide part)

[0061] 62R: Inflow path

[0062] 62T: Exhaust path Detailed implementation mode

[0063] Hereinafter, the circular saw 10 as a working machine of the present embodiment will be described with reference to the drawings. In addition, the arrows UP, FR, and RH appropriately shown in the drawings respectively indicate the upper side, front side, and right side of the circular saw 10. Moreover, in the following description, when the up, down, front, back, left, and right directions are used for description, unless otherwise specified, they are assumed to represent the up, down, front, back, left, and right directions of the circular saw 10.

[0064] The circular saw 10 is configured as a tool for cutting a workpiece. As Figures 1 to 4 shown, the circular saw 10 has a tool body 20 that performs cutting on a workpiece. In addition, as Figure 2 and Figure 15As shown, the circular saw 10 has a dust collector housing 60 or a dust collection adapter 70 as a dust collector, and the dust collector housing 60 or the dust collection adapter 70 is used to collect chips as processed pieces generated during cutting. The dust collector housing 60 and the dust collection adapter 70 are configured to be detachable from the tool body 20, and depending on the dust collection form of the chips, the dust collector housing 60 or the dust collection adapter 70 is alternatively installed on the tool body 20 by an operator. Specifically, in the case where a dust collection device (dust collector, cleaner) driven by a power source (not shown) is not used to collect chips, the dust collector housing 60 is installed on the tool body 20, and in the case where a dust collection device is used to collect chips, the dust collection adapter 70 is installed on the tool body 20. Hereinafter, first, the structure of the tool body 20 will be described, and then the structures of the dust collector housing 60 and the dust collection adapter 70 will be described.

[0065] (Regarding the tool body 20) As Figures 1 to 7 shown, the tool body 20 is composed of the following components: a base 22, a housing 24, a drive mechanism 46 and a control unit 54 housed in the housing 24, and a battery pack 56. In addition, the tool body 20 has an adjustment mechanism 33 for connecting the housing 24 to the base 22.

[0066] (Regarding the base 22) The base 22 is formed in a substantially rectangular plate shape with the vertical direction as the plate thickness direction and the front-rear direction as the length direction. The lower surface of the base 22 is configured as a sliding surface 22A. During the cutting of the circular saw 10, the base 22 is placed on the upper side of the workpiece, and the sliding surface 22A slides along the upper surface of the workpiece.

[0067] In the base 22, a tool insertion portion 22B as a through hole is formed therethrough, and the tool insertion portion 22B is used to dispose the circular saw blade 12 as a tip tool. The tool insertion portion 22B is formed in a substantially long hole shape with the front-rear direction as the length direction. Here, the circular saw blade 12 is formed in a substantially circular plate shape with the left-right direction as the plate thickness direction, and the central portion of the circular saw blade 12 is fixed to the output shaft 50 so as to be integrally rotatable with the output shaft 50 of the drive mechanism 46 described later. Moreover, the circular saw blade 12 is disposed within the tool insertion portion 22B, the upper portion of the circular saw blade 12 protrudes upward from the base 22 (one side in the plate thickness direction of the base 22), and the lower end side portion of the circular saw blade 12 protrudes downward from the base 22 (the other side in the plate thickness direction of the base 22). Moreover, during the cutting of the workpiece, when viewed from the right side, the circular saw blade 12 rotates about the axis of the output shaft 50 toward one side ( Figure 7 the arrow A direction side).

[0068] In addition, a fixing wall 22C for fixing the fixing shaft 36 of the adjustment mechanism 33 described later is formed at the front end portion of the base 22 (see Figure 1 and Figure 4) The fixed wall 22C protrudes upward from the base 22 with the front-rear direction as the plate thickness direction. A fixing groove 22D is formed through the fixed wall 22C (refer to Figure 1 and Figure 4 ). When viewed from the front side, the fixing groove 22D is bent in a substantially arc shape protruding obliquely upward to the left.

[0069] (Regarding the housing 24) The housing 24 forms the outer contour of the tool main body 20 and is disposed above the base 22. The housing 24 is composed of the following components: a main body housing 25 that houses a drive mechanism 46 described later, a handle housing 26 that forms the upper part of the housing 24, and an inner cover 27.

[0070] The main body housing 25 includes a plurality of housing members and is integrally formed into a substantially bottomed cylindrical shape open to the right. A saw cover portion 25A protruding radially outward is formed at the right end portion of the main body housing 25 (refer to Figures 4 to 6 ). The saw cover portion 25A is formed into a substantially semicircular shape protruding upward when viewed from the right side. The saw cover portion 25A and the inner cover 27 described later together constitute a member that covers the upper part of the circular saw blade 12, and the saw cover portion 25A and the inner cover 27 correspond to the cover member of the present invention. Moreover, the saw cover portion 25A and the inner cover 27 are connected to the base 22 at the front end portion and the rear end portion by an adjustment mechanism 33 described later.

[0071] At the left end portion of the main body housing 25, a plurality of air inlets 25B are formed through the front and rear corner portions. The plurality of air inlets 25B are formed across the bottom wall (left end portion) and the front and rear side walls of the main body housing 25, and are arranged at a predetermined interval in the vertical direction.

[0072] The handle housing 26 is formed into a substantially D shape that is hollow when viewed from the left side, is disposed so as to cover the main body housing 25 from above and behind, and is connected to the main body housing 25. The upper end portion of the handle housing 26 is configured as a handle portion 26A for an operator to hold, and the handle portion 26A is inclined downward as it faces the rear side in a side view.

[0073] A trigger 30 is provided at the front side portion of the handle portion 26A. The trigger 30 protrudes downward from the handle portion 26A and is configured to be able to perform a trigger operation upward. In addition, on the handle portion 26A, above the trigger 30, a lock button 31 for locking the trigger operation of the trigger 30 is provided. Further, a switch mechanism (not shown) is provided inside the handle portion 26A. The switch mechanism has a switch (not shown) operated by the trigger 30. The switch is electrically connected to a control unit 54 described later and is configured to output an output signal corresponding to the operation state of the trigger 30 to the control unit 54.

[0074] In addition, the lower end portion of the rear side of the handle housing 26 is configured as a battery mounting portion 26B for mounting a battery pack 56 described later. A connector (not shown) is provided in the battery mounting portion 26B, and the connector is electrically connected to a control portion 54 described later.

[0075] The inner cover 27 is adjacently disposed on the right side of the saw cover portion 25A of the main body housing 25, and is configured to cover the circular saw blade 12 from above and the right side. Specifically, the inner cover 27 includes the following members: a cover side wall 27A having a substantially semi-circular plate shape that protrudes upward with the left-right direction as the plate thickness direction, a cover front wall 27B extending from the front end portion of the cover side wall 27A to the left side, a cover rear wall 27C extending from the rear end portion of the cover side wall 27A to the left side, and a cover upper wall 27D extending from the upper outer peripheral portion of the cover side wall 27A to the left side. When viewed from the right side, the cover upper wall 27D is curved in an arc shape protruding upward corresponding to the outer peripheral portion of the circular saw blade 12, and the front end portion of the cover upper wall 27D extends along the front-rear direction in a side view. On the left side of the front end portion of the inner cover 27, a cover left wall 27P that constitutes a left wall of a chip discharge portion 27E described later is provided.

[0076] Moreover, the inner cover 27 is adjacently disposed on the right side of the saw cover portion 25A of the main body housing 25, and the cover front wall 27B is fixedly fastened to the front end portion of the saw cover portion 25A, and the cover rear wall 27C is fixedly fastened to the rear end portion of the saw cover portion 25A. As a result, a tool accommodation space 28 that is open downward is formed inside the inner cover 27 and the saw cover portion 25A (refer to Figure 5 and Figure 7 ), and the upper portion of the circular saw blade 12 is accommodated in the tool accommodation space 28.

[0077] At the front end portion of the inner cover 27, a substantially rectangular cylindrical chip discharge portion 27E having the up-down direction as the axial direction is formed. The chip discharge portion 27E is disposed at a position that is more forward than the center portion of the circular saw blade 12 in a side view. More specifically, the front end portion of the circular saw blade 12 is disposed below the chip discharge portion 27E. The front wall of the chip discharge portion 27E is constituted by the cover front wall 27B, the right wall of the chip discharge portion 27E is constituted by the cover side wall 27A, and the left wall of the chip discharge portion 27E is constituted by the cover left wall 27P. The rear wall of the chip discharge portion 27E is configured as a partition wall 27F that serves as a partitioning portion. A partition slit 27G that is open downward is formed in the lower portion of the partition wall 27F (refer to Figure 13) The outer peripheral portion on the front end side of the circular saw blade 12 is disposed within the dividing slit 27G. Thus, the chip discharge portion 27E is formed in a cylindrical shape by the front cover wall 27B, the cover side wall 27A, the cover left wall 27P, and the partition wall 27F. In addition, the upper end portion of the chip discharge portion 27E is formed in a shape protruding upward from the arcuate cover upper wall 27D. Further, the upper side opening portion of the chip discharge portion 27E is configured as the chip discharge port 27H which is the first opening portion. Thereby, it is configured that when cutting the workpiece, the chips rolled up by the circular saw blade 12 are introduced into the chip discharge portion 27E and discharged upward from the chip discharge port 27H. Thus, the lower end of the chip discharge portion 27E becomes the entrance of the rolled-up chips. In addition, in the chip discharge portion 27E, the partition wall 27F and the front cover wall 27B are inclined in a direction away from each other as they face downward in a side view, and the opening area at the portion of the chip discharge port 27H is set to be the smallest.

[0078] In the cover upper wall 27D, a cover opening 27J which is the second opening portion is formed therethrough at a position behind the chip discharge port 27H and closer to the front side than the center portion of the circular saw blade 12. That is, the cover opening 27J is disposed on the downstream side in the rotation direction of the circular saw blade 12 with respect to the chip discharge port 27H. The cover opening 27J is constituted by opening hole portions 27J1 which are a plurality of (four portions in the present embodiment) holes. The opening hole portions 27J1 are formed in a long hole shape with the left-right direction as the longitudinal direction and are arranged in the front-rear direction (the rotation direction of the circular saw blade 12). The opening areas of the opening hole portions 27J1 constituting the chip discharge port 27H and the cover opening 27J are each set to an area that allows the chips generated during the cutting process to pass through. In addition, the opening area of the cover opening 27J (the total area of the plurality of opening hole portions 27J1) is set to be smaller than the opening area of the chip discharge port 27H.

[0079] In addition, the partition wall 27F is disposed between the chip discharge port 27H and the cover opening 27J, and the upper portion of the tool accommodation space 28 is separated front and rear by the partition wall 27F below the chip discharge port 27H and the cover opening 27J.

[0080] On the cover upper wall 27D, a first rib 27K (refer to [[ID=IO]] Figure 4 ) is formed behind the cover opening 27J. The first rib 27K extends in the front-rear direction with the left-right direction as the plate thickness direction. Further, on the cover upper wall 27D, a second rib 27L (refer to Figure 4 ) is formed behind the first rib 27K. Similar to the first rib 27K, the second rib 27L extends in the front-rear direction with the left-right direction as the plate thickness direction.

[0081] A cover protrusion 27M for mounting a dust collector housing 60 or a dust collection adapter 70 described later (an element generally regarded as a mounting portion, refer toFigure 4 and Figure 7 ). The cover projection 27M projects forward from the cover front wall 27B and extends in the left-right direction. On the other hand, an installation groove portion 27N (an element grasped as an installation portion in a broad sense, refer to Figure 7 ) for installing a dust collector housing 60 or a dust collection adapter 70 described later is formed in the cover rear wall 27C. The installation groove portion 27N opens rearward and extends in the left-right direction. The inner cover 27 is a part of the dust collection structure in the present invention.

[0082] (Regarding the adjustment mechanism 33) As Figures 4 to 6 shown, the adjustment mechanism 33 is configured as a mechanism for connecting the housing 24 to the base 22, and has: a protrusion amount adjustment mechanism for adjusting the protrusion amount of the adjustment circular saw blade 12 downward from the base 22, and an inclination adjustment mechanism for adjusting the angle of the circular saw blade 12 protruding downward from the base 22 with respect to the base 22. The adjustment mechanism 33 includes a connection plate 34, a link 40, and a fixed rod 43.

[0083] The connection plate 34 is disposed between the saw cover portion 25A and the inner cover 27 and the fixed wall 22C of the base 22 with the front-rear direction as the plate thickness direction. The lower end portion of the connection plate 34 is rotatably supported by a front-side connection shaft 35 with the front-rear direction as the axial direction, and the front-side connection shaft 35 is fixed to the base 22. The front-side connection shaft 35 is disposed on the right side of the fixed wall 22C and at a position that is the center of the fixed groove 22D. When viewed from the front, the fixed groove 22D extends along the circumferential direction of the front-side connection shaft 35. In addition, a fixed shaft 36 is provided on the connection plate 34. The fixed shaft 36 protrudes forward from the connection plate 34 with the front-rear direction as the axial direction, is inserted into the fixed groove 22D of the base 22 so as to be relatively movable, and is disposed at the lower end portion of the fixed groove 22D. Moreover, a fixed arm 37 is screwed to the front end portion of the fixed shaft 36, and the fixed shaft 36 is fixed to the fixed wall 22C by the fixed arm 37.

[0084] A pair of left and right support pieces 34A that bend rearward are formed at the upper end portion of the connection plate 34, and the support pieces 34A are disposed with the left-right direction as the plate thickness direction. A support shaft 38 with the left-right direction as the axial direction is spanned between the pair of support pieces 34A. Moreover, the front end portions of the saw cover portion 25A and the inner cover 27 are rotatably supported by the support shaft 38. Thus, the front end portion of the housing 24 is connected to the base 22 through the support shaft 38, the connection plate 34, and the fixed shaft 36. In addition, the front end portion of the housing 24 is configured to be rotatable about the axis of the front-side connection shaft 35 and is configured to be rotatable about the axis of the support shaft 38. When the housing 24 rotates about the axis of the front-side connection shaft 35, the circular saw blade 12 can be inclined with respect to the base 22.

[0085] The connecting rod 40 is disposed on the left side at the rear of the saw cover portion 25A. The connecting rod 40 is composed of the following members: a connecting rod main body portion 40A that extends in the vertical direction; and a connecting rod connecting portion 40B that extends rearward from the lower end portion of the connecting rod main body portion 40A. The connecting rod connecting portion 40B is formed in a substantially L shape when viewed from above. That is, the rear end portion of the connecting rod connecting portion 40B bends to the right side and is disposed at the rear of the saw cover portion 25A and the inner cover 27. The top end portion of the connecting rod connecting portion 40B is rotatably supported by a rear connecting shaft 41 (refer to Figure 6 ) having an axial direction in the front-rear direction. The rear connecting shaft 41 is fixed to the base 22 and is arranged coaxially with the front connecting shaft 35.

[0086] The connecting rod main body portion 40A is curved in a substantially arc shape that protrudes rearward when viewed from the side. Specifically, the connecting rod main body portion 40A is curved in a substantially arc shape centered on the support shaft 38 when viewed from the side. A connecting rod groove 40C is formed in the connecting rod main body portion 40A. The connecting rod groove 40C extends along the length direction of the connecting rod main body portion 40A and penetrates in the left-right direction. A connecting rod shaft 42 having an axial direction in the left-right direction is inserted into the connecting rod groove 40C so as to be relatively movable. The right end portion of the connecting rod shaft 42 is fixed to the saw cover portion 25A. Thus, it is configured that the housing 24 rotates about the support shaft 38 by the relative movement of the connecting rod shaft 42 in the connecting rod groove 40C. That is, it is configured to change the posture of the circular saw 10 and adjust the protruding amount of the circular saw blade 12 downward with respect to the base 22.

[0087] Specifically, in Figure 7 the initial state of the circular saw 10 shown, the connecting rod shaft 42 is disposed at the lower end portion of the connecting rod groove 40C, and the protruding amount of the circular saw blade 12 downward with respect to the base 22 is the largest. On the other hand, it is configured that by disposing the connecting rod shaft 42 at the upper end portion of the connecting rod groove 40C, the protruding amount of the circular saw blade 12 downward with respect to the base 22 is the smallest (the state shown in Figure 9 is hereinafter referred to as the minimum protrusion state). In addition, the left end portion of the connecting rod shaft 42 protrudes to the left side more than the connecting rod main body portion 40A, and an external thread is formed on the outer peripheral portion of the left end portion of the connecting rod shaft 42.

[0088] The fixed rod 43 is formed in a substantially long plate shape that extends in the front-rear direction with the left-right direction as the plate thickness direction. A nut 44 is provided at the front end portion of the fixed rod 43, and the nut 44 is screwed onto the left end portion of the link shaft 42. In addition, a washer (not shown) is provided between the nut 44 and the link main body portion 40A. Moreover, by rotating the fixed rod 43, the washer is fastened to the link main body portion 40A, so that the saw cover portion 25A (housing 24) is fixed to the link 40 via the link shaft 42. That is, the rear end portion of the housing 24 is connected to the base 22 via the link 40 and the rear side connecting shaft 41. The link 40, the link main body portion 40A, the rear side connecting shaft 41, the connecting plate 34, the support shaft 38, the fixed rod 43, and the nut 44 are part of the protrusion amount adjusting mechanism. In addition, it is configured that by releasing the fixed state of the fixed arm 37 with respect to the fixed shaft 36, the housing 24 can rotate about the axes of the front side connecting shaft 35 and the rear side connecting shaft 41, and the angle of the circular saw blade 12 with respect to the base 22 can be changed. Specifically, although not shown, it is configured that the housing 24 can be tilted to the right with respect to the base 22. The connecting plate 34, the front side connecting shaft 35, the fixed shaft 36, the fixed arm 37, the rear side connecting shaft 41, the fixed wall 22C, and the fixed groove 22D are part of the tilting mechanism.

[0089] (Regarding the drive mechanism 46) As Figure 5 shown, the drive mechanism 46 includes a motor 47 and an output shaft 50. The motor 47 is housed in the main body housing 25 and is electrically connected to a control unit 54 described later. The motor 47 has a rotating shaft 47A with the left-right direction as the axis. Moreover, the left end portion of the rotating shaft 47A is rotatably supported by a first motor bearing 48 fixed to the main body housing 25, and the right side portion of the rotating shaft 47A is rotatably supported by a second motor bearing 49 fixed to the main body housing 25. The right end portion of the rotating shaft 47A protrudes to the right from the second motor bearing 49, and a pinion 47B is formed at the right end portion of the rotating shaft 47A.

[0090] The output shaft 50 is arranged inside the main body housing 25 with the left-right direction as the axis. Specifically, the output shaft 50 is arranged below the right end portion of the rotating shaft 47A of the motor 47 and is slightly rearward with respect to the rotating shaft 47A, and is rotatably supported by the main body housing 25. At the left end portion of the output shaft 50, an output gear (not shown) can be integrally rotated.

[0091] Furthermore, a transmission gear (reduction mechanism) (not shown) is provided between the rotary shaft 47A and the output shaft 50. The transmission gear is configured as a two-speed gear and meshes with the pinion 47B of the rotary shaft 47A and the output gear of the output shaft 50. In addition, the right end portion of the output shaft 50 is configured as a tool mounting portion, and the tool mounting portion is disposed within the tool housing space 28. The tool mounting portion is formed in a substantially cylindrical shape that is open to the right, and an external thread is formed on the inner peripheral portion of the tool mounting portion. Moreover, the central portion of the circular saw blade 12 is externally inserted into the tool mounting portion, and the circular saw blade 12 is fixed to the right end portion of the output shaft 50 by a bolt BL. Thus, when the motor 47 is driven, the output shaft 50 and the circular saw blade 12 rotate about the axis of the output shaft 50.

[0092] In addition, the lower portion of the circular saw blade 12 is covered by a protective cover 52 (see Figures 1 to 4 ). The protective cover 52 is formed in a substantially semi-circular shape that protrudes downward when viewed from the right, and is formed in a concave shape that is open upward. In addition, the protective cover 52 is rotatably connected to the output shaft 50 about the axis of the output shaft 50 (see Figure 5 ). Furthermore, the protective cover 52 is biased about the axis of the output shaft 50 by a biasing spring (not shown) and is held in the Figures 1 to 4 shown position. Moreover, when the circular saw 10 is used for cutting, the protective cover 52 rotates about the axis of the output shaft 50 to the other side against the biasing force of the biasing spring by the workpiece, thereby exposing the cutting edge of the circular saw blade 12.

[0093] (Regarding the control unit 54) As Figure 3 shown, the control unit 54 is housed in the front end portion of the battery mounting portion 26B in the handle housing 26. In the control unit 54, the switch mechanism of the trigger 30 and the motor 47 are electrically connected. Thus, by operating the trigger 30, the motor 47 is driven and the circular saw blade 12 rotates about the axis of the output shaft 50.

[0094] (Regarding the battery pack 56) The battery pack 56 is formed in a substantially rectangular parallelepiped shape. Moreover, the battery pack 56 is mounted on the battery mounting portion 26B of the circular saw 10 from the rear side. Furthermore, the battery pack 56 has a connector (not shown), and is configured such that in the mounted state of the battery pack 56, the connector is connected to the connector of the battery mounting portion 26B to supply power from the battery pack 56 to the control unit 54.

[0095] (Regarding the dust collection housing 60) As Figures 1 to 3 and Figures 6 to 13As shown, the dust collecting housing 60 is detachably mounted on the inner housing 27 of the tool main body 20 and is disposed adjacent to the upper side of the inner housing 27. Moreover, it is configured to accumulate the chips discharged from the chip discharge portion 27E of the inner housing 27 within the dust collecting housing 60. The dust collecting housing 60 includes a housing main body 62, a mounting rod 64, and a cover member 66. The dust collecting housing 60 is a part of the dust collecting structure in the present invention.

[0096] (Regarding the housing main body 62) The housing main body 62 is formed in a hollow box shape that extends in the front-rear direction and is open to the rear side, and is curved in a substantially arc shape that bulges upward corresponding to the upper wall 27D of the inner housing 27 when viewed from the side. Specifically, the housing main body 62 includes a housing bottom wall 62A, a housing right wall 62B and a housing left wall 62C that serve as housing side walls, a housing upper wall 62D, and a housing front wall 62E. The housing main body 62 is composed of housing members that are divided into two parts in the left-right direction, and these housing members are assembled with each other. The rear portion of the housing left wall 62C is formed in a shape that is recessed to the right so that the hand of the operator holding the grip handle portion 26A is difficult to touch.

[0097] As Figures 7 to 10 shown, the inner peripheral surface of the front end portion of the housing main body 62 is curved in a substantially arc shape that bulges obliquely upward to the front when viewed from the side, and the lower end portion of the front end portion of the housing main body 62 is disposed adjacent to the upper side of the front wall 27B of the inner housing 27. In addition, at the lower end portion of the front end portion of the housing main body 62, a mounting groove portion 62F that is open to the rear side is formed (refer to Figure 7 and Figure 8 ). Moreover, the housing protrusion 27M of the inner housing 27 is disposed within the mounting groove portion 62F, and the housing protrusion 27M and the mounting groove portion 62F are engaged in the up-down direction. Thereby, the upward movement of the front end portion of the housing main body 62 is restricted. In addition, the front portion of the housing bottom wall 62A is curved in a substantially arc shape that bulges upward corresponding to the upper wall 27D of the inner housing 27. In the housing bottom wall 62A, engaging grooves 62G that are open to the lower side are formed at positions corresponding to the first rib 27K and the second rib 27L of the inner housing 27. The engaging grooves 62G extend in the front-rear direction, and the first rib 27K and the second rib 27L are inserted into the engaging grooves 62G, and the housing main body 62 and the inner housing 27 are engaged in the left-right direction (refer to Figure 12 ). In addition, the right end portion of the housing bottom wall 62A is bent downward so as to cover the upper outer peripheral portion of the inner housing 27 from the right side, and the lower end portion of the housing right wall 62B is bent to the left and connected to the right end portion of the housing bottom wall 62A (refer to Figure 12 ).

[0098] As Figure 11 and Figure 12As shown, inside the housing main body 62, a housing partition wall 62H is formed at the front end side portion. The housing partition wall 62H is formed in a rectangular plate shape with the substantially front-rear direction (specifically, the direction from the upper rear to the lower front) as the plate thickness direction, and the inside of the housing main body 62 is partitioned front and rear by the housing partition wall 62H. Moreover, the rear portion of the housing main body 62 (the portion more rearward than the housing partition wall 62H) is configured as a dust collection chamber 62J, and the front portion of the housing main body 62 (the portion more forward than the housing partition wall 62H) is configured as a dust collection passage portion 62K. In addition, the housing partition wall 62H is disposed at a position more forward than the center portion of the circular saw blade 12 when viewed from the side. Further, at the upper end portion of the housing partition wall 62H, a dust collection chamber entrance / exit portion 62L is formed through, and the dust collection chamber entrance / exit portion 62L is disposed adjacent to the lower side of the housing upper wall 62D and extends in the left-right direction from the housing right wall 62B to the housing left wall 62C. That is, the dust collection chamber 62J and the dust collection passage portion 62K are communicated through the dust collection chamber entrance / exit portion 62L. The housing partition wall 62H is an example of the first partition portion in the present invention. The housing partition wall 62H functions as a partition portion for partitioning the transfer portion and the storage portion in the present invention.

[0099] At the front portion of the housing bottom wall 62A (the portion more forward than the housing partition wall 62H), a housing opening 62M is formed through, and the housing opening 62M is disposed above the chip discharge port 27H and the cover opening 27J of the inner cover 27. That is, the dust collection passage portion 62K is opened downward through the housing opening 62M.

[0100] In the dust collection passage portion 62K, a partition wall 62N for partitioning the inside of the dust collection passage portion 62K is formed. The partition wall 62N extends forward from the lower edge portion of the dust collection chamber entrance / exit portion 62L when viewed from the side, the front portion of the partition wall 62N inclines downward as it goes forward, and is curved in a substantially arc shape so as to protrude forward and obliquely upward. The front end portion of the partition wall 62N is disposed adjacent to the upper side of the partition wall 27F of the inner cover 27 and is disposed at the middle portion in the front-rear direction of the housing opening 62M (refer to Figure 7 and Figure 8 ). Thereby, the housing opening 62M is divided into a housing inlet portion 62M1 constituting the front portion of the housing opening 62M and a housing outlet portion 62M2 constituting the rear portion of the housing opening 62M. That is, the partition wall 62N divides the inflow path 62R (inflow portion) and the exhaust path 62T (outflow portion) in the front-rear direction. Moreover, the housing inlet portion 62M1 is disposed above the chip discharge port 27H of the inner cover 27, and the housing outlet portion 62M2 is disposed above the cover opening 27J of the inner cover 27. The partition wall 62N is an example of the second partition portion for partitioning the space of the transfer portion in the present invention.

[0101] Furthermore, in the dust collection passage portion 62K, a guide wall 62P as a guide portion is formed between the partition wall 62N and the upper wall 62D of the housing. Figures 10 to 12 ) The guide wall 62P extends in a substantially front-rear direction with the left-right direction as the plate thickness direction. The rear end portion of the guide wall 62P is disposed at the middle portion in the left-right direction of the dust collection chamber entrance portion 62L. The dust collection chamber entrance portion 62L is divided by the guide wall 62P into a dust collection chamber entrance portion 62L1 as an entrance portion that constitutes the right side portion of the dust collection chamber entrance portion 62L, and a dust collection chamber exit portion 62L2 as an exit portion that constitutes the left side portion of the dust collection chamber entrance portion 62L. That is, the guide wall 62P divides the inflow path 62R (inflow portion) and the exhaust path 62T (outflow portion) described later in the left-right direction. In addition, it is configured such that the position of one end in the left-right direction of the entrance portion (dust collection chamber entrance portion 62L1) is different from the position of one end in the left-right direction of the exit portion (dust collection chamber exit portion 62L2) due to the guide wall 62P. In addition, the dust collection chamber entrance portion 62L1 and the dust collection chamber exit portion 62L2 are configured such that the position of the other end in the left-right direction is also different. The guide wall 62P is an example of a third dividing portion that divides the space of the transfer portion in the present invention.

[0102] Accordingly, the dust collection chamber entrance portion 62L1 and the dust collection chamber exit portion 62L2 are arranged and disposed in the left-right direction. Therefore, in a state where the housing 24 does not tilt to the right with respect to the base 22, in either the initial state or the minimum protrusion state of the circular saw 10, the dust collection chamber entrance portion 62L1 and the dust collection chamber exit portion 62L2 are disposed at overlapping positions in the up-down direction. In other words, at least a part of the dust collection chamber entrance portion 62L1 and the dust collection chamber exit portion 62L2 are at the same position in the up-down direction. In addition, in either a state where the housing 24 tilts to the right with respect to the base 22 or in either the initial state or the minimum protrusion state of the circular saw 10, a part of the dust collection chamber entrance portion 62L1 and a part of the dust collection chamber exit portion 62L2 are disposed at overlapping positions in the up-down direction. In addition, the opening area of the dust collection chamber entrance portion 62L1 is set to 80% to 120% of the opening area of the dust collection chamber exit portion 62L2 (in the present embodiment, the opening area of the dust collection chamber entrance portion 62L1 and the opening area of the dust collection chamber exit portion 62L2 are set to be substantially the same area).

[0103] In addition, the guiding wall 62P is inclined to the left as it faces the front side, and the front end portion of the guiding wall 62P is connected to the left housing wall 62C of the housing body 62. Thus, in the dust collection passage portion 62K, an inflow path 62R is formed with one end being the housing inlet portion 62M1 and the other end being the dust collection chamber inlet portion 62L1, and the dust collection chamber 62J and the chip discharge portion 27E of the inner cover 27 communicate with each other through the inflow path 62R. That is, the inflow path 62R is a passage that connects the housing inlet portion 62M1 and the dust collection chamber inlet portion 62L1 located behind it. Moreover, the flow path area of the inflow path 62R is set to become smaller as it faces the dust collection chamber inlet portion 62L1 side (downstream side of the flow path) due to the guiding wall 62P. That is, the flow path area on the downstream side of the inflow path 62R is set to be smaller than the flow path area on the upstream side of the inflow path 62R.

[0104] In addition, in the partition wall 62N, an exhaust hole portion 62S is formed through in a portion surrounded by the guiding wall 62P and the left housing wall 62C. Thus, in the dust collection passage portion 62K, an exhaust path 62T is formed with one end being the housing outlet portion 62M2 and the other end being the dust collection chamber outlet portion 62L2, and the dust collection chamber 62J and the cover opening portion 27J of the inner cover 27 communicate with each other through the exhaust path 62T. That is, the exhaust path 62T is a passage that connects the housing outlet portion 62M2 and the dust collection chamber outlet portion 62L2 located behind it.

[0105] (Regarding the loading and unloading rod 64) As Figure 7 and Figure 10 shown, the loading and unloading rod 64 is formed in a substantially V-shaped block that is open to the rear lower oblique side in a side view. Specifically, the loading and unloading rod 64 is composed of the following components: a engaging arm 64A that extends in the vertical direction; and a handle rod portion 64B that extends from the upper end portion of the engaging arm 64A to the rear lower oblique side. At the upper end portion of the engaging arm 64A, a rod shaft 64C is formed with the left-right direction as the axial direction, and the rod shafts 64C protrude outward from the loading and unloading rod 64 in the left-right direction. Moreover, the rod shafts 64C are rotatably connected to the housing body 62 at the lower end portion of the rear end of the housing body 62. In addition, the loading and unloading rod 64 is biased in the counterclockwise direction when viewed from the right by a spring (not shown).

[0106] At the lower end portion of the engaging arm 64A, a hook portion 64D that protrudes forward is formed. Moreover, the hook portion 64D is inserted into the mounting groove portion 27N of the inner cover 27, and the hook portion 64D and the mounting groove portion 27N are engaged in the vertical direction. Thus, the upward movement of the rear end portion of the dust collection housing 60 is restricted. Moreover, an operator holds the handle rod portion 64B and rotates the loading and unloading rod 64 clockwise when viewed from the right to release the engagement state between the hook portion 64D and the mounting groove portion 27N, thereby removing the dust collection housing 60 from the inner cover 27.

[0107] (Regarding the lid member 66) The lid member 66 is composed of the following members: a lid main body portion 66A, which constitutes the front portion of the lid member 66; and a lid cylinder portion 66B, which constitutes the rear portion of the lid member 66. The lid main body portion 66A is formed in a substantially rectangular box shape that is open toward the front side. Moreover, the lid main body portion 66A is connected to the rear end portion of the housing main body 62 so as to close the rear end portion of the housing main body 62. Specifically, the upper end portion of the lid main body portion 66A is rotatably connected to the upper end portion of the rear end portion of the housing main body 62 in the left-right direction as the axis.

[0108] The lid cylinder portion 66B is formed in a substantially cylindrical shape with the front-rear direction as the axis and projects rearward from the lid main body portion 66A. In addition, the interior of the lid cylinder portion 66B communicates with the interior of the lid main body portion 66A, and a bottomed cylindrical cap 68 is installed at the rear end portion of the lid cylinder portion 66B.

[0109] (Regarding the dust collection adapter 70) As Figure 15 and Figure 16 shown, when using a power-driven dust collection device (not shown) to suck chips during cutting, instead of the dust collection housing 60, the dust collection adapter 70 is installed on the inner cover 27 of the tool main body 20. When installing the dust collection adapter 70 on the inner cover 27, the dust collection adapter 70 is arranged adjacent to the upper side of the inner cover 27 in the same manner as the dust collection housing 60. Moreover, in the dust collection mode using the dust collection adapter 70, the chips discharged from the chip discharge port 27H and the cover opening 27J of the inner cover 27 are discharged to the dust collection device (outside the dust collection adapter 70) via the dust collection adapter 70. The dust collection adapter 70 is composed of an adapter main body 72 and an adapter connection portion 74. In addition, similar to the dust collection housing 60, a handling rod 64 is provided on the adapter main body 72.

[0110] (Regarding the adapter main body 72) The adapter main body 72 is formed in a hollow box shape that extends in the front-rear direction, similar to the housing main body 62 of the dust collection housing 60, and is curved in a substantially arc shape that bulges upward corresponding to the upper wall 27D of the inner cover 27 when viewed from the side. Specifically, the adapter main body 72 is composed of the following members: an adapter bottom wall 72A, an adapter right wall 72B, an adapter left wall 72C, an adapter upper wall 72D, an adapter front wall 72E, and an adapter rear wall 72F. The adapter main body 72 is composed of adapter members that are divided into two parts in the left-right direction, and these adapter members are assembled with each other. In addition, the lower end portion of the adapter right wall 72B projects downward more than the adapter bottom wall 72A to cover the outer peripheral portion of the upper end of the cover side wall 27A of the inner cover 27 from the right side.

[0111] At the lower end of the front wall 72E of the adapter, a mounting groove portion 72G that opens to the rear side is formed. Moreover, the cover projection 27M of the inner cover 27 is disposed within the mounting groove portion 72G, and the cover projection 27M and the mounting groove portion 72G are engaged in the vertical direction. Thereby, the upward movement of the front end portion of the adapter body 72 is restricted. At the rear end portion of the adapter body 72, a loading and unloading rod 64 is rotatably provided in the left-right direction axis, and the hook portion 64D of the loading and unloading rod 64 is engaged with the mounting groove portion 27N of the inner cover 27. Thereby, the upward movement of the rear end portion of the adapter body 72 is restricted.

[0112] In addition, the bottom wall 72A of the adapter is curved in a substantially arc shape that bulges upward corresponding to the upper cover wall 27D of the inner cover 27. In the adapter bottom wall 72A, at positions corresponding to the first rib 27K and the second rib 27L of the inner cover 27, an engaging groove 72H that opens downward is formed. Moreover, although not shown in the figure, the first rib 27K and the second rib 27L are inserted into the engaging groove 72H, and the adapter body 72 and the inner cover 27 are engaged in the left-right direction.

[0113] At the front end portion of the adapter body 72, a cylindrical connecting tube portion 72J is formed in the up-down direction axis. The upper end portion of the connecting tube portion 72J is formed in a substantially cylindrical shape and protrudes upward beyond the adapter upper wall 72D. On the inner peripheral surface of the upper end portion of the connecting tube portion 72J, a pair of upper and lower guide rail portions 72L that protrude radially inward are formed, and the guide rail portions 72L extend in the entire circumference of the connecting tube portion 72J.

[0114] The lower portion of the connecting tube portion 72J is formed in a substantially rectangular tube shape. Specifically, the peripheral wall of the lower portion of the connecting tube portion 72J is composed of a part of the adapter right wall 72B, the adapter left wall 72C, and the adapter front wall 72E. The connecting tube portion 72J penetrates in the up-down direction, and the lower end opening portion of the connecting tube portion 72J is configured as a main suction port 72K. Moreover, the upper end portion of the chip discharge portion 27E of the inner cover 27 is inserted into the main suction port 72K.

[0115] In addition, on the rear wall of the lower portion of the connecting tube portion 72J, a communication hole 72M that penetrates in the front-rear direction is formed, and the communication hole 72M is formed in a substantially rectangular shape with the left-right direction as the length direction. Further, in the adapter bottom wall 72A, behind the connecting tube portion 72J, a sub-suction port 72N is formed through, and the sub-suction port 72N is disposed above the cover opening portion 27J of the inner cover 27.

[0116] Inside the adapter main body 72, a first connecting wall 72P is formed that connects the upper edge portion of the communication hole 72M and the rear edge portion of the sub-suction port 72N. The first connecting wall 72P extends rearward from the communication hole 72M, and the rear end portion of the first connecting wall 72P bends obliquely downward and rearward. Further, inside the adapter main body 72, a second connecting wall 72R is formed that connects the lower edge portion of the communication hole 72M and the front edge portion of the sub-suction port 72N. The second connecting wall 72R extends obliquely downward and rearward from the communication hole 72M. The first connecting wall 72P and the second connecting wall 72R are connected to the adapter right wall 72B and the adapter left wall 72C. Thus, in the adapter main body 72, a sub-suction path 70A serving as a second discharge path is formed with one end being the sub-suction port 72N and the other end being the communication hole 72M.

[0117] The adapter connection portion 74 is formed in a substantially cylindrical shape with the vertical direction as the axis, and the upper portion of the adapter connection portion 74 inclines rearward as it goes upward. Moreover, a hose of the dust collection device is connected to the upper end portion of the adapter connection portion 74. The lower end portion of the adapter connection portion 74 can be rotatably inserted into the upper end portion of the connection cylinder portion 72J of the adapter main body 72. On the outer peripheral portion of the lower end portion of the adapter connection portion 74, a pair of upper and lower guide grooves 74A that open radially outward of the adapter connection portion 74 are formed, and the guide grooves 74A extend in the entire circumference of the adapter connection portion 74. Moreover, the guide portion 72L of the adapter main body 72 can be rotatably inserted into the guide grooves 74A. Thus, the lower end portion of the adapter connection portion 74 is rotatably connected to the adapter main body 72 with the vertical direction as the axis. That is, the inside of the adapter connection portion 74 communicates with the inside of the lower end portion of the connection cylinder portion 72J, and the communicating portion is configured as a main suction path 70B serving as a first discharge path.

[0118] Moreover, a first dust collection path 76 that communicates the inside of the inner cover 27 (that is, the inside of the inner cover 27, the tool accommodation space 28) with the outside of the dust collection adapter 70 (that is, the dust collection device) is formed by the chip discharge portion 27E of the inner cover 27 and the main suction path 70B. The first dust collection path 76 extends in a substantially vertical direction, and is configured such that chips in the tool accommodation space 28 are conveyed toward the dust collection device side via the first dust collection path 76.

[0119] Further, a second dust collection path 78 that communicates the tool accommodation space 28 with the main suction path 70B is formed by the sub-suction path 70A of the dust collection adapter 70 and the cover opening portion 27J of the inner cover 27. Thus, the second dust collection path 78 is disposed on the downstream side in the rotation direction of the circular saw blade 12 with respect to the first dust collection path 76 and is connected to the first dust collection path 76. Moreover, it is configured that chips not inserted into the first dust collection path 76 are discharged to the main suction path 70B via the second dust collection path 78 and are conveyed toward the dust collection device side together with the chips in the main suction path 70B.

[0120] In addition, in the first dust collection path 76, the flow path area at the position of the chip discharge port 27H of the chip discharge portion 27E is set to be the smallest, and in the second dust collection path 78, the flow path area at the position of the communication hole 72M is set to be the smallest. Further, the minimum flow path area of the second dust collection path 78 is set to be equal to or smaller than the minimum flow path area of the first dust collection path 76.

[0121] In addition, in the dust collection adapter 70, a cover portion 72S is formed that connects the lower end portion of the second connection wall 72R and the lower end portion of the rear wall of the connection cylinder portion 72J. The cover portion 72S is disposed above the opening hole portion 27J1 that is disposed at the most front side (upstream side in the rotation direction of the circular saw blade 12) in the cover opening portion 27J of the inner cover 27, and closes the opening hole portion 27J1 from above. Thus, it is configured that the opening area of the cover opening portion 27J when the dust collection adapter 70 is installed in the inner cover 27 is smaller than the opening area of the cover opening portion 27J when the dust collection housing 60 is installed in the inner cover 27.

[0122] (Function and effect) Next, the dust collection of chips when the dust collection housing 60 and the dust collection adapter 70 are installed in the tool main body 20 will be described, and the functions and effects of the present embodiment will be described.

[0123] When using the circular saw 10 configured as described above, the base 22 is placed on the workpiece, and the trigger 30 is operated by pressing. As a result, while the motor 47 is driven, the driving force of the motor 47 is transmitted to the circular saw blade 12, so that the circular saw blade 12 rotates together with the output shaft 50. Then, by moving the circular saw 10 forward, a cutting process is performed on the workpiece.

[0124] (Regarding the dust collection using the dust collection housing 60) When performing a cutting process on a workpiece, the chips generated during the cutting process are rolled up to the upper side of the circular saw blade 12 by the rotational force of the circular saw blade 12. In addition, an air flow flowing from the tool accommodation space 28 into the dust collection housing 60 is generated by the rotational force of the circular saw blade 12 or the movement of the chips. Thus, as Figure 7 and Figure 10As shown, the chips flow into the dust collector housing 60 together with the air. The air flowing inside the dust collector housing 60 is shown as AR1. The air AR1 flows inside the dust collector housing 60 as indicated by the arrow. Specifically, the chips and the air AR1 flow together from the chip discharge portion 27E of the inner cover 27 into the inflow path 62R of the dust collector housing 60. Moreover, the chips and the air AR1 flowing into the inflow path 62R are discharged from the dust collection chamber inlet portion 62L1 into the dust collection chamber 62J, and the chips are accumulated in the dust collection chamber 62J. More specifically, the chips entering the dust collection chamber 62J from the dust collection chamber inlet portion 62L1 are accumulated in a manner of piling up on the upper side of the housing bottom wall 62A. In addition, the air AR1 conveyed into the dust collection chamber 62J is exhausted from the dust collection chamber outlet portion 62L2 to the exhaust path 62T. Then, the air AR1 exhausted to the exhaust path 62T is exhausted into the tool accommodation space 28 through the cover opening 27J of the inner cover 27.

[0125] Use Figure 14 A more detailed description of the dust collection situation of the present invention will be given. In Figure 14 it, the inner cover 27 and the dust collector housing 60 constituting the dust collection structure of the present invention are described, and the saw blade 12 is also described. In addition, Figure 14 It shows a state of a cross-sectional view of the dust collection structure (the inner cover 27 and the dust collector housing 60) of the present invention cut along a plane extending vertically and horizontally through a position on the right side of the guide wall 62P and on the left side of the right end of the housing partition wall 62H as viewed from the right side. In Figure 14In this case, the passage through which the chips (processed pieces) generated by machining move to the dust collection chamber 62J along with the air flow is denoted as the inflow portion S1, and the passage through which the air flows from the dust collection chamber 62J to the outside of the dust collection structure (tool accommodation space 28) is denoted as the outflow portion S2. In addition, to facilitate understanding that the inflow portion S1 and the outflow portion S2 are spatially separated, the dust collection chamber 62J is denoted as the dust collection space S3. The inflow portion S1 is the space from the lower end opening of the chip discharge portion 27E to the dust collection chamber entrance portion 62L (dust collection chamber inlet portion 62L1), and includes the chip discharge portion 27E, the chip discharge port 27H, the housing inlet portion 62M1, the inflow path 62R, and the dust collection chamber inlet portion 62L1. The lower end opening of the chip discharge portion 27E is the inflow inlet portion (beginning end of the inflow portion) in the present invention, and the dust collection chamber inlet portion 62L1 is the inflow outlet portion (ending end of the inflow portion) in the present invention. The outflow portion S2 is the space from the dust collection chamber entrance portion 62L (dust collection chamber outlet portion 62L2) to the cover opening portion 27J, and includes the dust collection chamber outlet portion 62L2, the exhaust path 62T, the housing outlet portion 62M2, and the cover opening portion 27J. The dust collection chamber outlet portion 62L2 is the outflow inlet portion (beginning end of the outflow portion) in the present invention, and the cover opening portion 27J is the outflow outlet portion (ending end of the outflow portion) in the present invention. The inflow portion S1 and the outflow portion S2 are part of the transfer portion in the present invention, and the dust collection chamber 62J (dust collection space S3) is an example of the storage portion in the present invention. The inflow portion S1 and the outflow portion S2 are spaces (passages) through which chips or air move and pass. As Figure 14 shown, the inflow portion S1 and the outflow portion S2 are divided by the partition wall 62N and the guide wall 62P. The inflow portion S1 and the outflow portion S2 are divided left and right by the guide wall 62P. To facilitate understanding of the region divided by the guide wall 62P, the Figure 14 region of the guide wall 62P in is shaded with a dot pattern. In addition, the inflow portion S1 and the outflow portion S2 are divided by the partition wall 62N in the front-rear direction and the up-down direction. The inflow portion S1 is indicated by a dotted line. The outflow portion S2 is indicated by a dashed line. The dust collection space S3 is indicated by a single dotted line.

[0126] The circular saw 10 is a working machine that performs cutting operations forward, and chips are generated around the working direction end (front end) of the tip tool. In order to suppress the deterioration of visibility of the working part or the deterioration of workability caused by the enlargement of the main body, it is also preferable to arrange at least most of the part for dust collection (storage) of chips in an area further back than the chip generation part. In addition, in order to collect chips by the action of gravity, the dust collection chamber needs to be formed in a container shape with at least a bottom on the lower side. Therefore, for the dust collection structure of the present invention, by providing a housing partition wall 62H connected to the lower part (housing bottom wall 62A) of the dust collection structure (dust collection housing 60) and extending upward, the dust collection chamber 62J (dust collection space S3) is separated from the transfer part (inflow part S1, outflow part S2), and the dust collection chamber 62J is formed in a container shape. In addition, the housing partition wall 62H is configured to extend upward, and on the other hand, it is not connected to the housing upper wall 62D, thereby forming a dust collection chamber entrance part 62L as a communication part. Therefore, the chips generated at the lower part of the tool insertion part 22B move upward through the chip discharge part 27E by the flow of air generated by the cutting impulse and the rotation of the saw blade 12, pass through the inflow path 62R and exceed the vertical position P1 (height) of the upper end of the housing partition wall 62H, and move upward from here and then move backward and exceed the front-rear position P2 of the upper end of the housing partition wall 62H. The chips are held in the dust collection chamber 62J by the action of gravity at the time point when they are located further back than the front-rear position P2. Conversely, in a state where it is located in front of the front-rear position P2, when the impulse of the chips or the flow of air that assists in movement disappears, the chips move downward inside the inflow path 62R and are discharged to the tool accommodation space 28 and are not dust-collected. Therefore, in the case of achieving appropriate dust collection, it is important to move the chips further back than the front-rear position P2. The air flowing into the inside of the dust collection chamber 62J (S3) is removed to the outside of the dust collection chamber 62J (S3) through the outflow part S2.

[0127] Thus, in the circular saw 10 equipped with the dust collecting housing 60, a chip discharge port 27H for conveying chips in the tool accommodation space 28 to the dust collecting chamber 62J side of the dust collecting housing 60 and a cover opening 27J for conveying the air AR1 exhausted from the dust collecting chamber 62J into the tool accommodation space 28 are formed in the inner cover 27. In addition, a dust collecting chamber inlet 62L1 for conveying the chips discharged from the chip discharge port 27H to the dust collecting chamber 62J and a dust collecting chamber outlet 62L2 for conveying the air AR1 in the dust collecting chamber 62J to the cover opening 27J are formed in the dust collecting housing 60. Thereby, the chips in the tool accommodation space 28 can be conveyed into the dust collecting chamber 62J via the chip discharge port 27H and the dust collecting chamber inlet 62L1 and accumulated in the dust collecting chamber 62J. In addition, the air AR1 conveyed into the dust collecting chamber 62J together with the chips can be conveyed back to the tool accommodation space 28 side via the dust collecting chamber outlet 62L2 and the cover opening 27J. That is, the air AR1 conveyed into the dust collecting housing 60 together with the chips during cutting can be returned to the tool accommodation space 28. Thereby, an increase in the pressure of the dust collecting chamber 62J can be suppressed. In addition, since the inflow portion S1 and the outflow portion S2 are brought together in the front portion of the dust collecting structure, it is easy to ensure the internal space of the dust collecting chamber 62J (S3). Assuming that the cover opening 27J is provided at a position more rearward than the center of the saw blade 12 (the axis of the output shaft 50), the necessity of providing an air passage in the lower part of the dust collecting chamber 62J increases, and thus there is a risk that the internal space of the dust collecting chamber 62J becomes smaller or the dust collecting housing 60 becomes larger upward. However, according to the present embodiment, such a situation can be suppressed.

[0128] Moreover, the dust collecting chamber inlet 62L1 and the dust collecting chamber outlet 62L2 are located at positions higher than the vertical position P1 (height) of the upper end of the housing partition wall 62H. Therefore, when a dust collecting space is formed below the dust collecting chamber inlet 62L1 and the dust collecting chamber outlet 62L2 as in the present embodiment, the volume of the dust collecting space (dust collecting chamber 62J) can be ensured to be large, and the chips discharged from the dust collecting chamber inlet 62L1 into the dust collecting chamber 62J can be prevented from flowing back from the dust collecting chamber 62J to the dust collecting chamber outlet 62L2. As described above, according to the circular saw 10 of the present embodiment, chips can be appropriately collected in the dust collecting chamber 62J. Further, the housing partition wall 62H extending upward from the lower part of the dust collecting housing 60 is configured to be inclined forward. In other words, the upper end of the housing partition wall 62H is located more forward than the lower end. Thereby, a larger space in the dust collecting chamber 62J can be ensured. In addition, even when the protruding amount of the circular saw blade 12 is minimized, the housing partition wall 62H will not be horizontal (parallel to the sliding surface 22A of the base 22), so that dust leakage can be suppressed.

[0129] In addition, as described above, when the dust collection housing 60 is installed on the tool main body 20, the air AR1 that is conveyed into the dust collection chamber 62J during cutting returns to the tool accommodation space 28 inside the inner cover 27. Therefore, for example, compared with a structure in which the air AR1 conveyed into the dust collection chamber 62J is exhausted from the right wall 62B or the upper wall 62D of the housing to the outside of the housing main body 62, it is possible to suppress the exhausted air AR1 from interfering with the work of the operator. Specifically, when exhausting air from the right wall 62B or the upper wall 62D of the housing, there is a risk of scattering dust and the like accumulated in the surroundings, but this can be suppressed in the present embodiment. Thus, compared with the above exhaust form, the workability during cutting can be improved.

[0130] In addition, as Figure 14 shown, etc., the dust collection chamber inlet portion 62L1 and the dust collection chamber outlet portion 62L2 are configured to overlap in the vertical direction. That is, the dust collection chamber inlet portion 62L1 and the dust collection chamber outlet portion 62L2 are configured such that at least a part thereof is in the same position in the vertical direction. In addition, even when the protruding amount of the circular saw blade 12 is minimized, the above positional relationship can be maintained. By doing so, it is easy to make the lower end position of the dust collection chamber entrance / exit portion 62L, which is a communication port with the outside of the dust collection chamber 62J, located above, and a large internal space of the dust collection chamber 62J can be ensured. Furthermore, the dust collection chamber inlet portion 62L1 and the dust collection chamber outlet portion 62L2 are configured such that at least a part thereof is in different positions in the horizontal direction. In other words, it is configured such that the positions of one end in the horizontal direction of the dust collection chamber inlet portion 62L1 and the dust collection chamber outlet portion 62L2 are different from each other. By doing so, as Figure 10 shown, it is easy to configure the flow of air in the dust collection chamber 62J to flow from one side in the horizontal direction to the other side. Therefore, it is possible to suppress the interference between the flow of chips that flow in from the dust collection chamber inlet portion 62L1 and move rearward and downward due to gravity and the flow of air that moves forward and upward in the dust collection chamber 62J to the dust collection chamber outlet portion 62L2, and thus a smooth flow of air AR1 can be achieved. In particular, since the dust collection chamber inlet portion 62L1 and the dust collection chamber outlet portion 62L2 have substantially the same area or shape for the balance of inflow and outflow, by making the position of one end in the horizontal direction of one of them different from that of the other, the center positions can be different (offset) in the horizontal direction, and thus it is easy to form a flow of air moving in the horizontal direction. In the present embodiment, the dust collection chamber inlet portion 62L1 and the dust collection chamber outlet portion 62L2 are arranged and configured adjacent to each other in the horizontal direction, that is, in positions that are completely offset in the horizontal direction. Thus, an appropriate flow of air AR1 and a compact dust collection housing 60 are achieved. However, the dust collection chamber inlet portion 62L1 and the dust collection chamber outlet portion 62L2 may not be completely offset in the horizontal direction, and may also be configured not to be adjacent and separated by a certain distance in the horizontal direction.

[0131] Furthermore, since the dust collection chamber inlet portion 62L1 and the dust collection chamber outlet portion 62L2 are arranged in the left-right direction, in a state where the housing 24 does not tip to the right with respect to the base 22, in either the initial state or the minimum protrusion state of the circular saw 10, the dust collection chamber inlet portion 62L1 and the dust collection chamber outlet portion 62L2 can be arranged at the same position in the up-down direction. Thus, it is possible to effectively suppress the backflow of the chips discharged from the dust collection chamber inlet portion 62L1 into the dust collection chamber 62J from the dust collection chamber 62J to the dust collection chamber outlet portion 62L2. In addition, by arranging the dust collection chamber inlet portion 62L1 and the dust collection chamber outlet portion 62L2 in the left-right direction, compared with the case of arranging them vertically, it is possible to suppress the enlargement of the size of the dust collection housing 60 in the up-down direction. In addition, by arranging the dust collection chamber inlet portion 62L1 and the dust collection chamber outlet portion 62L2 in the left-right direction, compared with the case of arranging them at positions separated from each other in the left-right direction, it is possible to suppress the enlargement of the size of the dust collection housing 60 in the left-right direction.

[0132] Thus, in the present embodiment, by making at least a part of the dust collection chamber inlet portion 62L1 and the dust collection chamber outlet portion 62L2 be at the same position in the up-down direction and making at least a part of the dust collection chamber inlet portion 62L1 and the dust collection chamber outlet portion 62L2 be different in the left-right direction, both ensuring the capacity of the dust collection chamber 62J and the smooth flow of the air AR1 are achieved, but even if only either one is achieved, the dust collection performance can be improved. These features can be realized by making the positions of one end (left end or right end) in the left-right direction of the dust collection chamber inlet portion 62L1 and the dust collection chamber outlet portion 62L2 different. The inner cover 27 covers a part of the outer periphery of the saw blade 12, but since the width in the left-right direction is not large, the chip discharge port 27H and the cover opening 27J are arranged adjacent to or separated from each other in the front-back direction instead of in the left-right direction. In order to spatially connect the chip discharge port 27H located in the front, the cover opening 27J, and the dust collection chamber 62J in the shape of a container, the passage from the chip discharge port 27H and the cover opening 27J toward the dust collection chamber 62J needs to be configured to extend upward and rearward. Here, in the case of providing passages extending upward and rearward from the chip discharge port 27H and the cover opening 27J with different positions in the front-back direction, in the normal case, the passage from the cover opening 27J located behind the chip discharge port 27H to the dust collection chamber 62J is formed inside (rear side and lower side) the passage from the chip discharge port 27H to the dust collection chamber 62J, and the dust collection chamber inlet portion 62L1 and the dust collection chamber outlet portion 62L2 are arranged vertically while having the same position in the left-right direction. However, in the present embodiment, due to the guide wall 62P, the positions of one end in the left-right direction of the dust collection chamber inlet portion 62L1 and the dust collection chamber outlet portion 62L2 are different. Thus, it is easy to adopt a structure that ensures the capacity of the dust collection chamber 62J or a structure that realizes the smooth flow of the air AR1.

[0133] In addition, in the inner cover 27, the chip discharge port 27H is disposed upstream of the circular saw blade 12 in the rotational direction with respect to the cover opening 27J. That is, on the downstream side of the circular saw blade 12 in the rotational direction with respect to the chip discharge port 27H, the air AR1 is exhausted from the cover opening 27J into the tool accommodation space 28. Therefore, it is possible to suppress the discharge of chips from the chip discharge port 27H into the dust collecting housing 60 from being obstructed by the air AR1 exhausted into the tool accommodation space 28. Thus, even if the cover opening 27J for exhausting the air AR1 of the dust collecting housing 60 is provided in the inner cover 27, the chips can be efficiently discharged from the chip discharge port 27H toward the dust collecting housing 60 side.

[0134] In addition, at the upper end of the tool accommodation space 28 of the inner cover 27, a partition wall 27F is provided, and the partition wall 27F is disposed between the chip discharge port 27H and the cover opening 27J. Thereby, it is possible to suppress the air AR1 exhausted from the cover opening 27J into the tool accommodation space 28 from flowing out toward the chip discharge portion 27E side. Therefore, also in this regard, it is possible to suppress the discharge of chips from the chip discharge port 27H into the dust collecting housing 60 from being obstructed by the air AR1 exhausted into the tool accommodation space 28. In addition, the cover opening 27J is composed of a plurality of opening holes 27J1. Therefore, the covering property of the inner cover 27 with respect to the circular saw blade 12 can be ensured, and the cover opening 27J for exhausting the air AR1 of the dust collecting housing 60 is provided in the inner cover 27. In addition, the opening area of the dust collecting chamber inlet portion 62L1 is set to 80% to 120% of the opening area of the dust collecting chamber outlet portion 62L2. Thereby, the opening area of the dust collecting chamber inlet portion 62L1 and the opening area of the dust collecting chamber outlet portion 62L2 can be set to substantially the same area. In other words, it is possible to suppress the ratio of the opening area of the dust collecting chamber inlet portion 62L1 to the opening area of the dust collecting chamber outlet portion 62L2 from becoming too large. Therefore, the chips can be efficiently discharged from the inflow path 62R into the dust collecting chamber 62J, and the air AR1 can be efficiently exhausted from the dust collecting chamber 62J to the exhaust path 62T.

[0135] In addition, in the dust collecting housing 60, an inflow path 62R is provided, and the chip discharge port 27H and the dust collecting chamber inlet portion 62L1 are communicated through the inflow path 62R. Further, in the dust collecting housing 60, an exhaust path 62T is provided, and the cover opening 27J and the dust collecting chamber outlet portion 62L2 are communicated through the exhaust path 62T. Moreover, the dust collecting chamber 62J is disposed on the rear side (downstream side in the rotational direction of the circular saw blade 12) of the inflow path 62R and the exhaust path 62T. Therefore, the chips and the air AR1 discharged from the chip discharge port 27H to the dust collecting housing 60 can be well transported into the dust collecting chamber 62J. In addition, it is possible to effectively suppress the chips discharged from the dust collecting chamber inlet portion 62L1 into the dust collecting chamber 62J from flowing back to the exhaust path 62T, and to exhaust the air AR1 from the exhaust path 62T into the tool accommodation space 28.

[0136] In addition, in the inflow path 62R, a guide wall 62P is provided. The guide wall 62P inclines to the right as it faces the rear side (the dust collection chamber 62J side) in a plan view. Therefore, the chips and the air AR1 conveyed to the dust collection chamber 62J are guided by the guide wall 62P and discharged obliquely to the right rear from the dust collection chamber inlet portion 62L1. That is, the chips and the air AR1 are discharged from the dust collection chamber inlet portion 62L1 in a manner away from the dust collection chamber outlet portion 62L2. Therefore, it is possible to effectively suppress the backflow of the chips and the air AR1 discharged from the dust collection chamber inlet portion 62L1 to the dust collection chamber outlet portion 62L2.

[0137] In addition, since the guide wall 62P inclines to the right as it faces the rear side as described above in a plan view, the flow path area of the inflow path 62R becomes smaller as it approaches the dust collection chamber inlet portion 62L1 side. Therefore, the flow velocity of the air flow discharged from the dust collection chamber inlet portion 62L1 to the dust collection chamber 62J can be increased. Therefore, it is possible to more effectively suppress the backflow of the chips and the air AR1 discharged from the dust collection chamber inlet portion 62L1 to the dust collection chamber outlet portion 62L2.

[0138] In addition, the dust collection chamber inlet portion 62L1 and the dust collection chamber outlet portion 62L2 are adjacently arranged below the upper wall 62D of the housing constituting the dust collection chamber 62J. That is, at the upper end portion of the dust collection chamber 62J, the dust collection chamber inlet portion 62L1 and the dust collection chamber outlet portion 62L2 are arranged. Thereby, it is possible to prevent the dust collection chamber inlet portion 62L1 and the dust collection chamber outlet portion 62L2 from being blocked by the chips accumulated in the dust collection chamber 62J.

[0139] (Regarding dust collection using the dust collection adapter 70) In the case of dust collection using the dust collection adapter 70, the hose of the dust collection device is connected to the upper end portion of the adapter connection portion 74 in the dust collection adapter 70. Moreover, by operating the dust collection device, the chips and the air in the tool accommodation space 28 are sucked into the dust collection device via the dust collection adapter 70.

[0140] Specifically, as Figure 16As shown, the chips and air AR2 rolled up by the circular saw blade 12 are inserted into the chip discharge portion 27E of the inner cover 27 from the tool accommodation space 28, and are discharged from the chip discharge portion 27E into the main suction path 70B of the dust collection adapter 70. Moreover, the chips and air AR2 discharged into the main suction path 70B are discharged from the upper end portion of the adapter connection portion 74 to the dust collection device. In addition, in the tool accommodation space 28, the chips that are not inserted into the chip discharge portion 27E are discharged together with the air AR3 from the cover opening portion 27J of the inner cover 27 into the sub-suction path 70A of the dust collection adapter 70. The chips and air AR3 discharged into the sub-suction path 70A are discharged from the communication hole 72M of the sub-suction path 70A into the main suction path 70B, and merge with the chips and air AR2 in the main suction path 70B. Thus, the chips and air AR3 discharged into the main suction path 70B are discharged from the upper end portion of the adapter connection portion 74 to the dust collection device.

[0141] In this way, when the dust collection adapter 70 is installed in the circular saw 10, the main suction path 70B connected to the chip discharge port 27H of the inner cover 27 is provided in the dust collection adapter 70. The main suction path 70B and the chip discharge port 27H together constitute the first dust collection path 76, and the first dust collection path 76 communicates the tool accommodation space 28 with the outside of the dust collection adapter 70. In addition, in the dust collection adapter 70, a sub-suction path 70A connected to the cover opening portion 27J of the inner cover 27 and the main suction path 70B is provided. The sub-suction path 70A and the cover opening portion 27J together constitute the second dust collection path 78, and the second dust collection path 78 communicates the tool accommodation space 28 with the main suction path 70B. Thus, during cutting, the chips in the tool accommodation space 28 can be sucked into the main suction path 70B and the sub-suction path 70A, and discharged to the outside of the dust collection adapter 70. That is, the chips that are not inserted into the chip discharge portion 27E of the inner cover 27 can be sucked from the cover opening portion 27J into the sub-suction path 70A and discharged to the outside of the dust collection adapter 70.

[0142] Here, the minimum flow path area of the second dust collection path 78 is set to be equal to or less than the minimum flow path area of the first dust collection path 76. Specifically, the area of the communication hole 72M of the sub-suction path 70A is set to be equal to or less than the area of the chip discharge port 27H of the inner cover 27. Thus, it is possible to suppress a decrease in the suction force of the first dust collection path 76 mainly for the insertion of chips rolled up from the front end portion of the circular saw blade 12, and discharge the chips from the first dust collection path 76 to the outside of the dust collection adapter 70. In addition, the chips that do not flow into the main suction path 70B and flow downstream in the rotation direction of the circular saw blade 12 can be sucked by the second dust collection path 78 and discharged to the main suction path 70B of the first dust collection path 76. Therefore, the dust collection efficiency of the chips can be improved, and a suitable dust collection structure can be formed.

[0143] In addition, at the upper end of the tool accommodation space 28 of the inner cover 27, a partition wall 27F is provided, and the partition wall 27F is disposed between the chip discharge port 27H and the cover opening 27J. Therefore, the chips rolled up by the circular saw blade 12 can be guided toward the chip discharge port 27H side by the partition wall 27F. Therefore, the chips rolled up by the circular saw blade 12 can be mainly guided to the first dust collection path 76 with high dust collection efficiency.

[0144] In addition, the cover opening 27J of the inner cover 27 is composed of a plurality of opening holes 27J1, and the opening holes 27J1 are arranged in the front-rear direction. Thereby, it is possible to suppress the opening area of the cover opening 27J from being larger than the opening area of the chip discharge port 27H, and the cover opening 27J is arranged in a relatively wide range in the front-rear direction. Therefore, it is possible to suck chips that have not been inserted into the chip discharge port 27H in a relatively wide range in the rotation direction of the circular saw blade 12 on the downstream side in the rotation direction of the circular saw blade 12 with respect to the chip discharge port 27H.

[0145] In addition, in the circular saw 10, the dust collection housing 60 and the dust collection adapter 70 are configured to be detachable from the inner cover 27, and according to the dust collection form of the chips, one of the dust collection housing 60 and the dust collection adapter 70 is installed on the inner cover 27. Moreover, when the dust collection housing 60 is installed on the inner cover 27, as described above, the chips are discharged from the chip discharge portion 27E of the inner cover 27 toward the dust collection housing 60 side, and the air AR1 from the dust collection housing 60 is exhausted from the cover opening 27J of the inner cover 27 into the tool accommodation space 28. On the other hand, when the dust collection adapter 70 is installed on the inner cover 27, as described above, the chips are discharged from the chip discharge portion 27E and the cover opening 27J of the inner cover 27 toward the dust collection adapter 70 side. That is, the cover opening 27J functions as a discharge portion for discharging the chips to the outside of the tool accommodation space 28 or an exhaust portion for exhausting the air into the tool accommodation space 28 according to the installed dust collection housing 60 and dust collection adapter 70. Thereby, different dust collectors (dust collection housing 60 and dust collection adapter 70) can be installed on the inner cover 27, and different forms of dust collection methods can be corresponded to. Therefore, an appropriate dust collection structure can be provided.

[0146] In addition, in the dust collecting adapter 70, a cover portion 72S is provided, and the cover portion 72S closes a part of the cover opening portion 27J of the inner cover 27. Therefore, compared with the case where the dust collecting housing 60 is installed in the inner cover 27, the opening area of the cover opening portion 27J can be reduced when the dust collecting adapter 70 is installed in the inner cover 27. Thus, in the inner cover 27 provided with dust collectors of different forms, the opening area of the cover opening portion 27J can be changed corresponding to different forms of dust collecting methods. That is, the opening area of the cover opening portion 27J when functioning as a discharge portion can be set smaller than the opening area of the cover opening portion 27J when functioning as an exhaust portion. Thus, in the dust collecting adapter 70, a reduction in the suction force of the main suction path 70B can be suppressed, and chips can be collected.

[0147] Moreover, the cover portion 72S closes the opening hole portion 27J1 disposed at the foremost side of the cover opening portion 27J. Therefore, chips that are not inserted into the chip discharge portion 27E of the inner cover 27 can be satisfactorily sucked into the sub-suction path 70A of the dust collecting adapter 70 from the cover opening portion 27J. That is, in the inner cover 27, since the partition wall 27F is disposed between the chip discharge port 27H and the cover opening portion 27J, chips that are not inserted into the chip discharge portion 27E flow beyond the lower side of the partition wall 27F toward the downstream side in the rotation direction of the circular saw blade 12. Therefore, it is difficult for the chips that flow beyond the lower side of the partition wall 27F and toward the downstream side to enter the opening hole portion 27J1 disposed at the foremost side of the cover opening portion 27J. Thus, compared with the structure in which the cover portion 72S closes the rear opening hole portion 27J1, chips that are not completely inserted into the chip discharge portion 27E can be satisfactorily conveyed into the sub-suction path 70A from the cover opening portion 27J.

[0148] In addition, in the present embodiment, in any of the initial state and the minimum protruding state of the circular saw 10, the entire dust collecting chamber inlet portion 62L1 and the dust collecting chamber outlet portion 62L2 of the dust collecting housing 60 are disposed at overlapping positions in the vertical direction, but as long as a part of the dust collecting chamber inlet portion 62L1 and a part of the dust collecting chamber outlet portion 62L2 are disposed at overlapping positions in the vertical direction.

[0149] In addition, in the present embodiment, the dust collecting chamber inlet portion 62L1 and the dust collecting chamber outlet portion 62L2 of the dust collecting housing 60 are arranged side by side in the left-right direction. That is, the front-rear positions of the dust collecting chamber inlet portion 62L1 and the dust collecting chamber outlet portion 62L2 coincide. Alternatively, the front-rear positions of the dust collecting chamber inlet portion 62L1 and the dust collecting chamber outlet portion 62L2 may be offset.

[0150] Further, in the present embodiment, in any one of the initial state and the minimum protrusion state of the circular saw 10, the entire dust collection chamber inlet portion 62L1 and the dust collection chamber outlet portion 62L2 of the dust collection housing 60 are arranged at overlapping positions in the vertical direction. However, at least in the initial state, the dust collection chamber inlet portion 62L1 and the dust collection chamber outlet portion 62L2 may be arranged at overlapping positions in the vertical direction.

[0151] Further, in the present embodiment, the dust collection chamber inlet portion 62L1 and the dust collection chamber outlet portion 62L2 are formed at the upper end portion of the housing partition wall 62H. However, the vertical positions of the dust collection chamber inlet portion 62L1 and the dust collection chamber outlet portion 62L2 can be arbitrarily changed as long as at least a part of them overlap each other in the vertical direction. For example, the dust collection chamber inlet portion 62L1 and the dust collection chamber outlet portion 62L2 may be arranged at the intermediate portion in the vertical direction of the housing partition wall 62H.

[0152] Further, in the present embodiment, the plurality of opening holes 27J1 of the cover opening 27J in the inner cover 27 are formed in a long hole shape with the left - right direction as the length direction and are arranged in the front - rear direction. Instead of this, the opening holes 27J1 may be formed in a long hole shape with the front - rear direction as the length direction and be arranged in the left - right direction.

Claims

1. A working machine comprising: The base is formed into a plate shape extending in the front-back and left-right directions; a housing supported on one side of the base in the plate thickness direction and accommodating a motor for driving a circular saw blade; as well as A dust collection structure including a dust collection chamber capable of collecting processing chips generated by driving the circular saw blade, The dust collecting structure is provided with an inlet portion serving as an entrance to the dust collecting chamber, an inlet portion connected to the inlet portion and serving as a passage for the processing sheet, and an outlet portion for conveying the air in the dust collecting chamber to a space for driving the circular saw blade. The circular saw blade is mounted on an output shaft driven by the motor. The inlet portion and the outlet portion are arranged side by side in the axial direction of the output shaft. At least a portion of the inlet portion and at least a portion of the outlet portion are arranged at the same position in a plate thickness direction of the base.

2. The work machine according to claim 1, wherein, The base is formed with a through hole for allowing a portion of the circular saw blade to protrude toward the other side in the plate thickness direction of the base. The housing is connected to an adjustment mechanism capable of adjusting the protrusion amount of the circular saw blade from the through hole. At least when the protrusion amount of the circular saw blade is maximum, at least a portion of the inlet portion and at least a portion of the outlet portion are arranged at the same position in the plate thickness direction of the base.

3. The working machine according to claim 1 or 2, wherein: The dust collecting structure includes a cover member provided on the housing and covering the circular saw blade. The cover member covers the circular saw blade from one side in a plate thickness direction of the base.

4. The work machine according to claim 3, wherein, The dust collecting structure includes a dust collecting casing detachable relative to the housing. The dust collecting housing is provided with the inlet portion and the outlet portion.

5. The work machine according to claim 4, wherein, The cover member is provided with a first opening for conveying the processed sheet to the dust collecting chamber and a second opening for conveying air in the dust collecting chamber to the inside of the cover member. The inlet portion connects the inlet portion and the first opening portion. The dust collecting housing includes an outflow portion connecting the outlet portion and the second opening portion, and the inflow portion.

6. The work machine according to claim 5, wherein, The first opening is arranged upstream of the second opening in the rotation direction of the circular saw blade.

7. The work machine according to claim 3, wherein, The area of the inlet portion is 80% to 120% of the area of the outlet portion.

8. The work machine according to claim 5, wherein, The dust collecting housing is provided with a partition wall that partitions the inflow portion and the outflow portion.

9. The work machine according to claim 8, wherein, The dust collecting housing is provided with a guide portion that divides the inflow portion and the outflow portion in a direction different from that of the partition wall.

10. The work machine according to claim 9, wherein, The chips or air discharged from the inlet portion into the dust collecting chamber are guided by the guide portion in a direction away from the outlet portion.

11. The working machine according to claim 4, The inlet and the outlet are arranged on one side of the dust collecting housing in a plate thickness direction.

12. A working machine that performs processing work in the forward direction. The working machine has a dust collecting structure for collecting dust generated by the processing operation. The dust collecting structure has: Dust collection room, storing dust; a transfer portion comprising an inlet portion for conveying dust to the dust collecting chamber, and an outlet portion for discharging air in the dust collecting chamber to the outside of the dust collecting structure; A first partitioning portion that extends upward while being connected to the lower portion of the dust collecting chamber to partition the dust collecting chamber and the transfer portion; and A communication portion that is located above the upper end of the first partitioning portion and allows the dust collecting chamber and the transfer portion to communicate with each other. In the working machine: An inlet portion connected to the inflow portion and an outlet portion connected to the outflow portion are provided in the communication portion. In the transfer portion, a second partitioning portion that partitions the inflow portion and the outflow portion in the front-rear direction and a third partitioning portion that partitions the inflow portion and the outflow portion in the left-right direction are provided, and the third partitioning portion is configured such that the positions of one ends of the inlet portion and the outlet portion in the left-right direction are different, and it is configured such that, when viewed in the left-right direction, a part of each of the inflow portion and the outflow portion overlaps.

13. The working machine according to claim 12, wherein at least a part of the inlet portion and the outlet portion is in different positions in the left-right direction or in the same position in the up-down direction.

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