Work equipment

Abstract

The objective of the present invention is improve workability. In a protrusion amount adjusting mechanism 80 of a circular saw 10, a fixing bolt 90 extending from a saw cover portion 34 is inserted, in such a way as to be capable of relative movement, through a link hole 83A in a link 83 supported on a base 20. Furthermore, rotating a fixing implement 92 tightens the saw cover portion 34 and the link 83 together by means of the fixing implement 92 and the fixing bolt 90, thereby fixing a circular saw main body 30 to the base 20. Here, a first operating lever 96 having a first operating portion 96E, and a second operating lever 98 having second operating portions 98B1 and 98B2 are linked to the fixing implement 92 so as to be capable of rotating integrally. Furthermore, with the fixing implement 92 in a fixed state, the first operating portion 96E is disposed to the rear of an axis 90E of the fixing bolt 90, and with the fixing implement 92 in a released state, one second operating portion 98B1 is disposed below the axis 90E of the fixing bolt 90. As a result, workability during work to adjust an amount of protrusion can be improved.

Description

[Technical Field]

[0001] The present invention relates to a work machine. [Background technology]

[0002] The work machine described in Patent Document 1 below has a cutting depth adjustment mechanism that allows the position of the main body relative to the base to be changed in the vertical direction, thereby adjusting the amount by which the circular saw blade protrudes from the base. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-200842 Summary of the Invention [Problem to be solved by the invention]

[0004] When adjusting the protrusion of the circular saw blade using the cutting depth adjustment mechanism, one hand holds the handle of the main body, the other holds the base, and the other hand moves the main body up and down. After adjustment, the other hand operates the operating part of the main body to secure the main body to the base. If the operating part is far from the base, the work of securing the main body to the base becomes complicated, which can lead to poor workability.

[0005] SUMMARY OF THE INVENTION In consideration of the above, an object of the present invention is to provide a work machine that can improve workability. [Means for solving the problem]

[0006] One or more embodiments of the present invention comprise: The device comprises a housing that accommodates a motor, a movable part connected to the housing so as to be movable relative to the housing, a first lever supported by the housing and rotatable about a rotation axis extending in a predetermined direction, and a second lever rotatable about the rotation axis, wherein the second lever is configured so that its relative rotation position about the rotation axis with respect to the first lever can be changed, and the first lever can be rotated by rotating the second lever, and by operating the first lever, it is possible to switch between a fixed state in which the position of the movable part with respect to the housing is fixed and a released state in which the fixed state is released and the housing is movable relative to the movable part, and it is also possible to switch between the fixed state and the released state by operating the second lever. It is a work machine.

[0008] One or more embodiments of the present invention comprise: The movable part is a base having an insertion portion and sliding on the workpiece during machining, the housing is provided above the base and has a tool bit that is inserted through the insertion portion and partially protrudes downward from the base, and the housing is connected to the base and the base is movable relative to each other and has a protrusion amount adjustment mechanism that is configured to adjust the amount of protrusion of the tool bit from the base, the protrusion amount adjustment mechanism having the first lever and the second lever, a fixed shaft that extends from the housing, and a link that is supported by the base and has a link hole through which the fixed shaft is inserted. It is a work machine.

[0009] One or more embodiments of the present invention comprise: The first lever extends in a direction perpendicular to the predetermined direction. With the first operation unit The second lever extends in a direction perpendicular to the predetermined direction. 2nd operation section By adjusting the rotational position of the second lever relative to the first lever, the rotational position of the second operating unit can be set to a position different from that of the first operating unit, and can also be set to the same position as that of the first operating unit. It is a work machine.

[0010] In one or more embodiments of the present invention, the first lever and The work machine has a fixing device that is connected so as to be rotatable together, and the fixing state and the released state are switched by the rotation of the fixing device.

[0011] One or more embodiments of the present invention are a work machine in which a male thread portion is formed at the tip of the fixed shaft, the fixing device is formed in a cylindrical shape with a female thread portion on the inner periphery, and the male thread portion is screwed into the female thread portion on the base end side of the fixing device.

[0013] In one or more embodiments of the present invention, the second operating portion is provided as a pair, and in the released state, one of the second operating portions is Rotation center position of the first lever and the second operating unit is disposed below the first operating unit and rearward of the first operating unit. Rotation center position of the first lever The work machine is disposed above the first operating section and rearward of the first operating section.

[0014] One or more embodiments of the present invention comprise: Rotation center position of the first lever In contrast, the first operating unit is In a direction perpendicular to the predetermined direction From the second operating unit Outside It is a work machine located next to the

[0015] One or more embodiments of the present invention are directed to a work machine in which the second lever is attached to the fixing tool and is configured so that the angle of the second lever relative to the fixing tool can be changed steplessly.

[0019] One or more embodiments of the present invention comprise: the first lever has a first operating portion extending in a direction perpendicular to the predetermined direction, and the second lever has a second operating portion extending in a direction perpendicular to the predetermined direction, The first operating unit Rotation center position of the first lever When the second operating portion is positioned in front of and above the Rotation center position of the first lever It is a work machine located behind and below the In one or more embodiments of the present invention, the movable part is a base having an insertion portion and sliding on the workpiece during machining, the housing is provided above the base and has a tool bit that is inserted into the insertion portion and a portion of which protrudes downward from the base, the base and the housing are connected to be movable relative to each other and a protrusion adjustment mechanism is provided that is configured to adjust the amount of protrusion of the tool bit from the base, the housing has a regulating portion that regulates rotation of the first lever, the first lever is turned to the released state by rotating it in one direction around the predetermined direction from the fixed state, and in the released state, rotation in one direction from a regulated position around the predetermined direction is regulated by the regulating portion, the housing is positioned at a position where the amount of protrusion is smallest, and when the first lever is in the regulating position, at least a portion of the second operating portion is positioned inside a circle that passes through a rotation center position of the first lever and is centered on the rear end of the underside of the base, as viewed in the predetermined direction. One or more embodiments of the present invention are a work machine in which the second lever is rotatable integrally with the first lever by restricting changes in the relative rotational position of the second lever about the rotational axis with respect to the first lever by a fixed member that contacts the second lever, and the relative rotational position of the second lever about the rotational axis with respect to the first lever can be changed by keeping the fixed member and the second lever out of contact. [Effects of the Invention]

[0020] According to one or more embodiments of the present invention, workability can be improved. [Brief explanation of the drawings]

[0021] [Figure 1] 1 is a plan view showing a circular saw according to an embodiment of the present invention, viewed from above; [Figure 2] 2 is a side view of the circular saw shown in FIG. 1 as seen from the left side. [Figure 3] 3 is a side view showing the circular saw body shown in FIG. 2 in a state where the circular saw body has been tilted from an initial position to a predetermined tilted position, with a motor housing and a battery holder removed. FIG. [Figure 4] 3 is a side view showing the circular saw body shown in FIG. 2 in a state where the circular saw body has been moved from an initial position to a maximum tilt position, with a motor housing and a battery holder removed. FIG. [Figure 5] 5 is a plan cross-sectional view (cross-sectional view taken along line 5-5 in FIG. 2) showing the inside of the circular saw body shown in FIG. 2 as seen from above. [Figure 6] 6 is a cross-sectional view (cross-sectional view taken along line 6-6 in FIG. 1) seen from the front side, showing a state in which the guide member shown in FIG. 1 is attached to a base. [Figure 7] 2 is an enlarged perspective view of the guide mechanism and its periphery shown in FIG. 1, seen obliquely from the right rear. FIG. [Figure 8] 8A is a plan view of the guide mechanism shown in FIG. 7 as seen from above, and FIG. 8B is a plan view showing a state in which the switching lever of FIG. 8A has been rotated from the adjustment position to the retracted position. [Figure 9] (A) is a cross-sectional view of the adjustment mechanism shown in Figure 8(A) as seen from the right rear side (cross-sectional view along line 9A-9A in Figure 8(A)), and (B) is a cross-sectional view of the adjustment mechanism shown in Figure 8(B) as seen from the rear side (cross-sectional view along line 9B-9B in Figure 8(B)). [Figure 10]10 is a cross-sectional view (cross-sectional view taken along line 10-10 in FIG. 2) seen from above, showing a fixed state between a link and a saw cover of the protrusion amount adjustment mechanism shown in FIG. 2; FIG. [Figure 11] FIG. 3 is an exploded perspective view of the protrusion amount adjustment mechanism shown in FIG. 2. [Figure 12] 10A is a perspective view of a modified example of the protrusion amount adjustment mechanism shown in FIG. 2, seen from diagonally rear left, and FIG. 10B is a side view of the modified example of the protrusion amount adjustment mechanism of FIG. 10A, seen from the left side. [Figure 13] 13(B) ) is a cross-sectional view (cross-sectional view taken along line 13-13 in FIG. 12(B)) showing the periphery of the lower end of the link in the modified example of the protrusion amount adjusting mechanism shown in FIG. 12(B). [Figure 14] 4 is a side view showing an example in which the first lever and the second lever of the protrusion amount adjustment mechanism shown in FIG. 3 are integrated. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0022] The following describes a circular saw 10 as a work machine according to this embodiment, with reference to the drawings. Note that the arrows UP, FR, and LH shown as appropriate in the drawings respectively indicate the upper side, front side, and left side of the circular saw 10. In the following description, when the up / down, front / rear, and left / right directions are used, they refer to the up / down, front / rear, and left / right directions of the circular saw 10 unless otherwise specified.

[0023] The circular saw 10 is configured as a power tool that cuts the workpiece W. Specifically, the circular saw 10 is placed on the workpiece W, and an operator positioned behind the circular saw 10 grips the handle portion 40 (described later) and moves the circular saw 10 forward (to one side in the first direction), thereby cutting the workpiece W.

[0024] 1 to 5, the circular saw 10 is configured to include a base 20, a circular saw body 30 as the main body, a guide mechanism 60 that guides the movement of the circular saw 10 during cutting, and a protrusion amount adjustment mechanism 80 that connects the circular saw body 30 to the base 20 and adjusts the amount of protrusion of the circular saw blade 12 of the circular saw body 30 from the base 20. Each component of the circular saw 10 will be described below.

[0025] (Regarding the base 20) The base 20 is made of metal and is formed in the shape of a generally rectangular plate with the thickness direction in the up-down direction and the length direction in the front-to-back direction. The underside of the base 20 is configured as a sliding surface 20A, and when the circular saw 10 is cutting, the sliding surface 20A is placed on the workpiece W and slides on the workpiece W (see FIG. 6).

[0026] An insertion portion 20B (see FIGS. 1 and 6) for accommodating a circular saw blade 12 serving as a tool insert is formed through the right portion of the base 20. The insertion portion 20B is formed in a generally rectangular shape with the longitudinal direction extending in the front-to-rear direction. The circular saw blade 12 is formed in a generally circular plate shape with the thickness direction extending in the left-to-right direction, and the center of the circular saw blade 12 is fixed to an output shaft 54 ​​of a drive mechanism 50 (described later) so as to be rotatable together with the circular saw blade 12. The circular saw blade 12 is disposed within the insertion portion 20B, with an upper portion of the circular saw blade 12 protruding upward from the base 20 and a lower end portion of the circular saw blade 12 protruding downward from the base 20. In other words, the insertion portion 20B is configured as a hole for allowing a portion of the circular saw blade 12 to protrude from the underside of the base 20 toward the workpiece W (the opposite side of the circular saw body 30).

[0027] An upwardly protruding base rib 20C is formed at each of the left and right ends of the base 20, and the base rib 20C extends in the front-rear direction. As shown in FIG. 6 , a left guide support portion 20D is provided at the front end portion of the base 20, to the right of the left base rib 20C, to support a guide member 62 (described later). A left guide hole 20E penetrates the left guide support portion 20D and the left base rib 20C in the left-right direction. The left guide hole 20E is formed in a generally rectangular shape with its longitudinal direction extending in the front-rear direction. The left base rib 20C is partially cut out so that the left end of the left guide hole 20E is open upward. A right guide hole 20F penetrates the right base rib 20C in the left-right direction. The right guide hole 20F has the same shape as the left guide hole 20E and is arranged coaxially with the left guide hole 20E.

[0028] (Regarding the Circular Saw Body 30) As shown in FIGS. 1, 2, and 5, the circular saw body 30 includes a housing 32 and a drive mechanism 50.

[0029] (Regarding the housing 32) The housing 32 is made up of multiple housing members, forms the outer shell of the circular saw body 30, and is disposed above the base 20. The housing 32 is connected to the base 20 by a protrusion adjustment mechanism 80, which will be described later. The connection of the housing 32 to the base 20 will be described later. The housing 32 is configured to include a saw cover portion 34 that covers the circular saw blade 12, a motor housing portion 36 that houses a drive mechanism 50, which will be described later, and a battery holder portion 38 to which the battery 14 is attached.

[0030] The saw cover portion 34 constitutes the right end portion of the housing 32. The saw cover portion 34 is formed in a generally semicircular plate shape with a thickness extending in the left-right direction and a concave shape that is open downward. The upper portion of the circular saw blade 12 is housed within and covered by the saw cover portion 34. A generally cylindrical cover tube portion 34A that protrudes to the left is formed at the lower end of the left wall of the saw cover portion 34 in the middle in the front-to-rear direction. A connecting tube portion 34B (see FIG. 1) is formed integrally with the front end portion of the saw cover portion 34, and the connecting tube portion 34B is formed in a generally cylindrical shape with the left-to-right direction as its axial direction.

[0031] A locking hole 34C (see FIG. 10) for locking a fixing bolt 90 of the protrusion amount adjustment mechanism 80 (described later) is formed through the rear end of the left wall of the saw cover portion 34, and the locking hole 34C is formed in a square shape. Furthermore, a fixing boss 34D (see FIG. 10) for fixing an operating lever biasing spring 104 of the protrusion amount adjustment mechanism 80 (described later) is integrally formed on the left wall of the saw cover portion 34, in front of the locking hole 34C. The fixing boss 34D is formed in a substantially cylindrical shape with its axial direction extending in the left-right direction and protrudes to the left from the saw cover portion 34. A restricting portion 34E is formed on the left wall of the saw cover portion 34. The restricting portion 34E abuts against a first operating lever 96 (described later) to restrict rotation of the first operating lever 96. The rotation position of the first operating lever 96 abutting against the restricting portion 34E is defined as the restricted position.

[0032] The motor housing 36 is formed in a generally cylindrical shape with a bottom that is open to the right. The motor housing 36 is disposed on the left side of the cylindrical cover portion 34A of the saw cover 34 and is fastened and fixed to the cylindrical cover portion 34A.

[0033] The battery holder portion 38 extends rearward from the upper portion of the motor housing portion 36 and is disposed at a distance to the left of the saw cover portion 34. The battery 14 is attached to the lower portion of the battery holder portion 38 from the rear, and is disposed below the battery holder portion 38 and at the rear of the motor housing portion 36. The battery 14 is electrically connected to a control portion (not shown) and a motor 51 of a drive mechanism 50, which will be described later.

[0034] A handle portion 40 is provided above the motor housing portion 36 and the battery holder portion 38. When viewed from the left side, the handle portion 40 is formed in a generally U-shape that opens diagonally downward and forward, and both ends of the handle portion 40 are connected to the motor housing portion 36 and the battery holder portion 38. A trigger 42 is provided on the handle portion 40 so that it can be pulled. The trigger 42 is electrically connected to the control portion, and operation of the trigger 42 activates a drive mechanism 50, which will be described later.

[0035] (Regarding the Drive Mechanism 50) As shown in FIG. 5, the drive mechanism 50 includes a motor 51 and an output shaft 54. The motor 51 is configured as a brushless motor, is housed in the motor housing 36, and is electrically connected to the control unit. The motor 51 has a motor shaft 51A whose axial direction is the left-right direction. The left end of the motor shaft 51A is rotatably supported by a first motor bearing 52 fixed to the motor housing 36, and the right portion of the motor shaft 51A is rotatably supported by a second motor bearing 53 fixed to the saw cover 34. The right end of the motor shaft 51A protrudes to the right from the second motor bearing 53, and a pinion gear is formed on the right end of the motor shaft 51A.

[0036] The output shaft 54, whose axial direction is the left-right direction, is disposed below the right end of the motor shaft 51A and is rotatably supported by the housing 32. An output gear (not shown) is provided on the output shaft 54 ​​so as to rotate integrally therewith. A two-stage transmission gear (not shown) is provided between the output gear and the output shaft 54, and the transmission gear is meshed with the pinion gear and output gear of the motor shaft 51A. The center of the circular saw blade 12 is fixed to the right end of the output shaft 54. As a result, when the motor 51 is driven, the output shaft 54 ​​and the circular saw blade 12 rotate around the axis of the output shaft 54.

[0037] The lower part of the circular saw blade 12 is covered with a protective cover 55 (see FIG. 2). The protective cover 55 is formed in a generally semicircular shape that is convex downward when viewed from the left side, and is formed in a concave shape that is open upward. The protective cover 55 is connected to the output shaft 54 ​​so as to be rotatable about the axis of the output shaft 54. The protective cover 55 is urged about the axis of the output shaft 54 ​​by a spring (not shown) and is held in the position shown in FIG. 2. When cutting with the circular saw 10, the workpiece W causes the protective cover 55 to rotate about the axis of the output shaft 54 ​​against the urging force of the spring, exposing the cutting portion of the circular saw blade 12.

[0038] (Regarding the Guide Mechanism 60) As shown in FIGS. 1 to 3 and 6 to 9, the guide mechanism 60 includes a guide member 62 and an adjustment mechanism .

[0039] (Regarding the guide member 62) The guide member 62 includes a guide bar 62A and a guide plate 62B serving as a guide portion. The guide bar 62A is formed in a generally rectangular rod shape extending in the left-right direction (second direction). The outer shape of the guide bar 62A as viewed in the left-right direction is set to be slightly smaller than the hole shapes of the left guide hole 20E and the right guide hole 20F in the base 20, and the guide bar 62A is inserted into the right guide hole 20F and the left guide hole 20E from the right side. In other words, the guide bar 62A is connected to the base 20 so as to be movable in the left-right direction. A bent portion 62A1 is formed on the right end side of the guide bar 62A, and the bent portion 62A1 is bent downward and to the left.

[0040] The guide plate 62B is formed as a generally elongated plate with its thickness in the left-right direction and extending in the front-rear direction. The guide plate 62B is disposed adjacent to the left side of the right end of the guide bar 62A, and the right end of the guide bar 62A is fixed to the middle of the right side of the guide plate 62B in the front-rear direction. By abutting the guide plate 62B against the end surface of the workpiece W, the circular saw 10 can be moved in the front-rear direction along the end surface of the workpiece W.

[0041] A fixing plate 64 formed of a leaf spring or the like is provided on the left guide support portion 20D of the base 20. The fixing plate 64 is formed in a generally U-shape that opens to the right when viewed from the front, and is disposed on the left guide support portion 20D so as to sandwich the left guide support portion 20D from both sides in the vertical direction. A guide fixing screw 66 is threadedly engaged with the left guide support portion 20D, and the lower end of the guide fixing screw 66 is disposed above the lower wall of the fixing plate 64. As a result, by rotating the guide fixing screw 66, the lower wall of the fixing plate 64 is pressed downward by the guide fixing screw 66, and the fixing plate 64 elastically deforms downward and presses the guide member 62 downward. As a result, the guide member 62 is fixed to the base 20.

[0042] (Regarding the Adjustment Mechanism 70) The adjustment mechanism 70 is provided on the base 20 and is arranged behind the left end portion of the guide member 62. The adjustment mechanism 70 is configured to include a switching lever 71 as a switching member, a roller unit 73, a lever biasing spring 76 as a biasing member, and a shaft biasing spring 77 as a shaft biasing member.

[0043] (Regarding the Switching Lever 71) As shown in FIGS. 7 to 9, the switching lever 71 is formed in a generally long block shape. A lever tubular portion 71A is formed in the longitudinal middle portion of the switching lever 71, and the lever tubular portion 71A is formed in a generally cylindrical shape with its axial direction extending in the vertical direction. The lever tubular portion 71A is fitted onto a rotation shaft 20G (see FIG. 8(A) and FIG. 8(B)) formed on the base 20 and is rotatably supported by the rotation shaft 20G. As a result, the switching lever 71 is rotatably connected to the base 20 with its axial direction extending in the vertical direction. Specifically, by rotating the switching lever 71, the switching lever 71 is switched between an adjustment position (position shown in FIG. 8(A)) and a retracted position (position shown in FIG. 8(B)) rotated clockwise from the adjustment position in a plan view. The rotation shaft 20G is formed in a generally cylindrical shape with its axial direction extending in the vertical direction, and a female thread is formed inside the rotation shaft 20G. A set screw 72 is threaded from above into the female thread of the rotation shaft 20G, and the set screw 72 prevents the switching lever 71 from coming off the rotation shaft 20G.

[0044] A spring accommodating portion 71B (see FIGS. 9A and 9B) that is open downward is formed on the underside of the lever cylinder portion 71A. When viewed from below, the spring accommodating portion 71B is formed in a circular shape with a larger diameter than the inner peripheral surface of the lever cylinder portion 71A, and is arranged coaxially with the lever cylinder portion 71A.

[0045] An arm portion 71C is provided at one end of the switching lever 71, and the arm portion 71C extends from the upper part of the lever cylinder portion 71A to one end side of the switching lever 71. The tip portion of the arm portion 71C is formed in a substantially cylindrical shape with a connecting hole 71D therein. An arm recess 71E (see FIGS. 9A and 9B) that is open downward is formed on the underside of the tip portion of the arm portion 71C. When viewed from below, the arm recess 71E is formed in a circular shape with a larger diameter than the connecting hole 71D, and is arranged coaxially with the connecting hole 71D.

[0046] A switching operation part 71F is provided at the other end of the switching lever 71, and the switching operation part 71F extends from the lower part of the lever cylinder part 71A toward the other end side of the switching lever 71. An operation knob part 71G is formed integrally with the switching operation part 71F, and the operation knob part 71G is formed in a substantially rectangular plate shape and extends upward from the switching operation part 71F.

[0047] (Regarding the Roller Unit 73) The roller unit 73 includes a roller shaft 74 serving as an adjustment shaft and a roller 75 serving as an adjustment member. The roller shaft 74 is formed in a generally stepped cylindrical shape (see FIGS. 9(A) and 9(B)). Specifically, the roller shaft 74 includes a knob 74A that forms the upper end of the roller shaft 74, a roller rotation shaft portion 74B that forms the vertical middle portion of the roller shaft 74, and a connecting shaft portion 74C that forms the lower end of the roller shaft 74. The roller rotation shaft portion 74B has a larger diameter than the connecting shaft portion 74C, and the knob 74A has a larger diameter than the roller rotation shaft portion 74B.

[0048] The roller rotation shaft 74B is inserted into the connecting hole 71D of the switching lever 71 so as to be relatively movable in the vertical direction and is rotatably supported by the connecting hole 71D. That is, the roller shaft 74 is connected to the arm 71C of the switching lever 71 so as to be rotatable about its axis in the vertical direction and movable in the vertical direction. The knob 74A serves as a grip for an operator and is disposed above the arm 71C. The lower end surface of the connecting shaft 74C is formed in a downwardly convex hemispherical shape. When the switching lever 71 moves between the adjustment position and the retracted position, the lower end surface of the roller shaft 74 slides on the upper surface of the base 20. When the switching lever 71 is in the retracted position, the lower end (one end) of the connecting shaft 74C fits into a fitting hole 20H formed in the base 20 (see FIG. 9B). This holds the switching lever 71 in the retracted position.

[0049] The roller 75 is formed in a generally cylindrical shape with its axis extending vertically. The roller 75 includes a core portion 75A that forms the radially inner portion of the roller 75 and a pressing portion 75B that forms the radially outer portion of the roller 75 (see FIGS. 9A and 9B). The core portion 75A is made of a metal material. The connecting shaft portion 74C of the roller shaft 74 is inserted into the core portion 75A from above by press-fitting or the like, so that the roller 75 is connected to the roller shaft 74 so as not to rotate relative to it. When the roller 75 is connected to the roller shaft 74, the lower end of the roller shaft 74 protrudes downward beyond the roller 75.

[0050] The pressing portion 75B is made of a rubber material having elasticity. That is, the pressing portion 75B is made of a material having a higher coefficient of friction than a metal material. When the switching lever 71 is in the adjustment position, the pressing portion 75B abuts against the rear surface of the guide bar 62A of the guide member 62.

[0051] 9(A) and 9(B), the lever-biasing spring 76 is configured as a torsion spring. The lever-biasing spring 76 is attached to the rotation shaft 20G of the base 20 and accommodated in the spring accommodation portion 71B of the switching lever 71. One end of the lever-biasing spring 76 is engaged with the base 20, and the other end of the lever-biasing spring 76 is engaged with the switching lever 71. The lever-biasing spring 76 urges the switching lever 71 counterclockwise in a plan view. As a result, when the switching lever 71 is in the adjustment position, the biasing force of the lever-biasing spring 76 presses the pressing portion 75B of the roller 75 against the rear surface of the guide bar 62A, thereby maintaining the switching lever 71 in the adjustment position. In addition, when an operator rotates the roller shaft 74 in this state, the guide member 62 in the unlocked state moves left and right. That is, the frictional force generated between the roller 75 and the guide member 62 transmits the rotational force of the roller 75, thereby moving the guide member 62. More specifically, the biasing force of the lever biasing spring 76, the hardness of the pressing portion 75B of the roller 75, and the like are set so that when a predetermined rotational force is applied to the roller 75, the guide member 62 moves left and right in conjunction with the rotation of the roller 75.

[0052] (Regarding the axial biasing spring 77) The axial biasing spring 77 is configured as a compression coil spring. The axial biasing spring 77 is attached to the lower end of the roller rotation shaft portion 74B of the roller shaft 74 and is housed in the arm recess 71E of the switching lever 71. The upper end of the axial biasing spring 77 is engaged with the upper surface of the arm recess 71E, and the lower end of the axial biasing spring 77 is engaged with the upper surface of the roller 75, so that the axial biasing spring 77 urges the roller unit 73 (roller shaft 74) downward. As a result, when the switching lever 71 is in the retracted position, the urging force of the axial biasing spring 77 causes the lower end of the roller unit 73 (roller shaft 74) to fit into the fitting hole 20H of the base 20, and the roller unit 73 is held by the base 20. As a result, the roller shaft 74, the fitting hole 20H of the base 20, and the axial biasing spring 77 form a holding mechanism that holds the roller 75 in the retracted position.When the worker lifts the roller shaft 74 upward against the biasing force of the axial biasing spring 77 in the retracted position, the engagement between the roller unit 73 and the base 20 is released, and the switching lever 71 is allowed to rotate toward the adjustment position.

[0053] 1 to 3, 10, and 11, the protrusion adjustment mechanism 80 is configured as a mechanism for connecting the circular saw body 30 to the base 20, and also as a mechanism for adjusting the amount of downward protrusion of the circular saw blade 12 from the base 20 (sliding surface 20A). The protrusion adjustment mechanism 80 is configured to include a front connecting member 81, a link 83, a fixing bolt 90 as a fixed shaft, a fixture 92, a first operating lever 96 (first lever) as a lever, a second operating lever 98 (second lever) as a lever, and an operating lever biasing spring 104.

[0054] The front connecting member 81 is formed in a generally block shape extending in the left-right direction. It is disposed in front of the saw cover 34 and fixed to the base 20. Shaft support portions 81A are provided at both left and right ends of the front connecting member 81. The shaft support portions 81A protrude rearward from the front connecting member 81 and are disposed adjacent to the outside of the connecting tube portion 34B of the saw cover 34 in the left-right direction. A main body support shaft 82, whose axial direction is the left-right direction, spans the pair of shaft support portions 81A. The main body support shaft 82 is inserted into the connecting tube portion 34B and rotatably supports the connecting tube portion 34B. This allows the front end of the saw cover 34 (circular saw body 30) to be rotatably connected to the base 20 with the axial direction being the left-right direction. More specifically, when the circular saw blade 12 protrudes a maximum amount from the base 20, the circular saw body 30 is disposed in the initial position (the position shown in FIG. 2 ). In addition, as the circular saw body 30 is displaced upward from the initial position, the amount of protrusion of the circular saw blade 12 from the base 20 decreases. The position of the circular saw body 30 displaced upward a predetermined distance (angle) from the initial position is defined as a predetermined tilted position (see FIG. 3). Note that FIG. 3 illustrates a state in which the first operating lever 96 abuts against the restricting portion 34E, thereby restricting rotation. Note that the position of the circular saw body 30 displaced maximum upward from the initial position is defined as a maximum tilted position (see FIG. 4). In this embodiment, the circular saw blade 12 does not protrude from the base 20 (protrusion amount is zero) at the maximum tilted position. Note that FIG. 4 illustrates a circle C centered at the rear end of the underside of the base 20. Circle C passes through the axis 90E when viewed in the axial direction of the axis 90E. Similar to FIG. 3, in FIG. 4, the first operating lever 96 abuts against the restricting portion 34E, thereby restricting rotation.

[0055] The link 83 is disposed adjacent to the left side of the rear of the saw cover section 34. Specifically, the link 83 is disposed between the saw cover section 34 and the battery holder section 38 and battery 14. The link 83 is formed in a generally elongated block shape with its thickness in the left-right direction, extends in the up-down direction, and is curved in an arc shape that convexly extends obliquely upward and rearward in a side view. Specifically, the center of the arc-shaped link 83 is disposed at a position offset from the axis of the main body support shaft 82. The lower end of the link 83 is rotatably supported by the base 20 with the left-right direction as its axial direction. Specifically, a support plate 84 fixed to the base 20 is provided behind the link 83, and a link support shaft 85 is provided on the support plate 84 with the left-right direction as its axial direction. The lower end of the link 83 is rotatably supported by the link support shaft 85. A link hole 83A is formed through the link 83 in the left-right direction, and the link hole 83A is formed in the shape of an elongated hole extending along the longitudinal direction of the link 83.

[0056] (Regarding the Fixing Bolt 90) As shown in Figures 10 and 11, the fixing bolt 90 is disposed with its axial direction aligned with the left-right direction. The fixing bolt 90 includes a head 90A that forms the base end of the fixing bolt 90, and a bolt body 90B that extends to the left from the head 90A. The head 90A is formed in a generally circular plate shape with its thickness aligned with the left-right direction. The bolt body 90B is formed in a generally cylindrical shape with a smaller diameter than the head 90A. A locking portion 90C is formed at the base end of the bolt body 90B, and the locking portion 90C is formed in a square shape similar to the locking hole 34C of the saw cover portion 34 when viewed in the axial direction of the fixing bolt 90. The fixing bolt 90 is inserted from the right side into the locking hole 34C in the left wall of the saw cover portion 34, and the locking portion 90C fits into the locking hole 34C. As a result, the fixing bolt 90 is connected to the saw cover portion 34 so as not to be able to rotate relative to the saw cover portion 34, and protrudes to the left from the saw cover portion 34. Note that the length of the locking portion 90C in the axial direction of the fixing bolt 90 is set so that when the fixing bolt 90 is connected to the saw cover portion 34, the locking portion 90C does not protrude to the left beyond the saw cover portion 34.

[0057] The fixing bolt 90 (bolt body 90B) is inserted into the link hole 83A of the link 83 so as to be relatively movable, and the tip of the bolt body 90B protrudes to the left of the link 83. When adjusting the protrusion amount of the circular saw blade 12, the fixing bolt 90 moves within the link hole 83A along the longitudinal direction of the link 83. Specifically, in the initial position of the circular saw body 30, the fixing bolt 90 is disposed at the lower end of the link hole 83A. Furthermore, although not shown, when the fixing bolt 90 is disposed at the upper end of the link hole 83A, the circular saw blade 12 does not protrude downward from the base 20. In other words, when the circular saw body 30 is in the tilted position, the fixing bolt 90 is disposed between the lower end and the upper end of the link hole 83A. A male thread portion 90D is formed on the outer periphery of the bolt body 90B, except for the locking portion 90C.

[0058] (Regarding the Fixture 92) The fixture 92 is formed in a generally cylindrical shape with its axial direction extending in the left-right direction as a whole. A female thread portion 92A is formed on the inner periphery of the fixture 92. The male thread portion 90D of the fixing bolt 90 is screwed into the female thread portion 92A on the base end side (right end side) of the fixture 92, and the fixture 92 is attached to the tip end portion of the fixing bolt 90.

[0059] As a result, when viewed from the tip end of the fixing bolt 90, by rotating the fixing device 92 clockwise (one side in the rotation direction), the fixing device 92 is displaced toward the base end side of the fixing bolt 90 (toward the link 83). Then, the fixing device 92 presses the link 83 to the right (toward the saw cover portion 34), and the link 83 (base 20) and the saw cover portion 34 (circular saw body 30) are fixed together by a tightening force acting from the fixing bolt 90 and the fixing device 92 to the saw cover portion 34 and the link 83 (hereinafter, this state of the fixing device 92 is referred to as the fixed state). On the other hand, when the fixing device 92 is in the fixed state, by rotating the fixing device 92 counterclockwise (the other side in the rotation direction), the fixing device 92 is displaced toward the tip end side of the fixing bolt 90 (in the direction away from the link 83), and the fixed state between the link 83 (base 20) and the saw cover portion 34 (circular saw body 30) is released (hereinafter, this state of the fixing device 92 is referred to as the released state).

[0060] A flange portion 92B is formed at the right end of the fixing device 92, and the flange portion 92B protrudes radially outward from the fixing device 92. A nut portion 92C serving as an engagement portion is formed on the fixing device 92 to the left of the flange portion 92B, and the outer shape of the nut portion 92C is formed in a regular hexagonal shape. A locking groove 92D is formed on the outer periphery of the fixing device 92 to the left of the nut portion 92C, and the locking groove 92D extends circumferentially around the fixing device 92 and is formed around the entire circumference of the fixing device 92. An E-ring 94 is locked in the locking groove 92D. The hexagonal outer shape of the nut portion 92C is intended to transmit the operating force of the first operating lever 96 to the fixing device 92, and a polygonal shape enables the transmission of high torque. The outer shape of the nut portion 92C may be any polygon, such as a pentagon or a rectangle.

[0061] (Regarding the First Operating Lever 96) The first operating lever 96 is formed in a generally elongated plate shape with its thickness extending in the left-right direction. The first operating lever 96 includes a lever engaging portion 96A constituting one end of the first operating lever 96 and a lever arm portion 96B extending from the lever engaging portion 96A. An engaging hole 96C is formed through the lever engaging portion 96A, and the inner periphery of the engaging hole 96C is formed in a zigzag pattern. Specifically, a plurality of engaging grooves 96D (12 in this embodiment) are formed in the inner periphery of the engaging hole 96C. The engaging grooves 96D are formed in a generally V-shape that opens toward the center of the engaging hole 96C and are arranged at equal intervals around the circumferential direction of the engaging hole 96C. The nut portion 92C of the fixing device 92 is inserted into the engaging hole 96C of the first operating lever 96 from the right side, and the lever engaging portion 96A is attached to the radially outer side of the fixing device 92.

[0062] When the lever engagement portion 96A is attached to the fixing device 92, the first operating lever 96 and the fixing device 92 are engaged in the circumferential direction of the fixing device 92 due to the inner circumferential shape of the engagement hole 96C and the outer circumferential shape of the nut portion 92C. As a result, the first operating lever 96 and the fixing device 92 are engaged to be able to rotate together, and the first operating lever 96, together with the fixing device 92, is configured to be switched between a locked state and a released state. In addition, a first operating portion 96E is provided at the tip of the lever arm portion 96B, and an operator grasps the first operating portion 96E to input an operating force (rotational force) to the first operating portion 96E. When the fixing device 92 is in the fixed state, the lever arm portion 96B extends diagonally upward and rearward from the lever engagement portion 96A, and the first operating portion 96E is disposed diagonally upward and rearward with respect to the axis 90E of the fixing bolt 90 (see FIG. 2). On the other hand, when the fixing device 92 is in the released state (a state in which the lever arm portion 96B of the first operating lever 96 is in contact with the restricting portion 34E), the lever arm portion 96B extends obliquely upward and forward from the lever engaging portion 96A, and the first operating portion 96E is disposed obliquely upward and forward with respect to the axis 90E of the fixing bolt 90 (see the first operating lever 96 indicated by the solid line and the two-dot chain line in FIG. 3). Note that the E-ring 94 restricts the first operating lever 96 from moving to the left.

[0063] The second operating lever 98 is formed in a generally V-shaped block shape when viewed from the left and right. Specifically, the second operating lever 98 includes a lever mounting portion 98A as an attachment portion, a pair of second operating portions 98B1 and 98B2, an attachment hole 98C, and a screw hole portion 98D. The lever mounting portion 98A is formed in a generally bottomed cylindrical shape that is open to the right. The lever mounting portion 98A is fitted onto the tip end (left end) of the fixing device 92 from the left side and is rotatably supported by the fixing device 92. A mounting hole 98C is formed through the left wall of the lever mounting portion 98A. A fixing screw 100 as a fastening member is inserted into the mounting hole 98C from the left side and threadedly engages with the female thread portion 92A of the fixing device 92, thereby fixing the second operating lever 98 to the fixing device 92 by the fixing screw 100. In other words, the first operating lever 96 and the second operating lever 98 are connected to the fixing device 92 so as to be rotatable together. As a result, the second operating lever 98 can be switched between a locked state and a unlocked state together with the fixture 92 and the first operating lever 96. A hexagonal socket set screw 102 is threaded into a threaded hole 98D formed in the side wall of the lever mounting portion 98A, and the tip of the hexagonal socket set screw 102 abuts against the side surface of the fixing screw 100. As a result, the hexagonal socket set screw 102 generates a pressing force on the second operating lever 98 (threaded hole 98D) and the fixing screw 100, and the resulting frictional force maintains the fixing screw 100 in a good fixed state to the second operating lever 98. The second operating lever 98 is fixed to the fixing device 92 in the rotational direction only by the pressing force of the fixing screw 100 against the lever mounting portion 98A (left side surface of the second operating lever 98) and the frictional force caused by the pressing force of the hexagonal socket set screw 102 against the second operating lever 98 (threaded hole 98D) and the fixing screw 100. Therefore, the relative position (rotational position) of the second operating lever 98 with respect to the first operating lever 96 (fixing device 92) can be changed continuously.

[0064] The second operating portions 98B1, 98B2 are formed in a generally triangular shape when viewed from the left side and extend radially outward from the lever mounting portion 98A. Specifically, the second operating portions 98B1, 98B2 are connected to the lever mounting portion 98A so that the widths of the second operating portions 98B1, 98B2 decrease radially outward from the lever mounting portion 98A when viewed from the left side. The distance from the axis 90E of the fixing bolt 90 to the tips of the second operating portions 98B1, 98B2 is set shorter than the distance from the axis 90E of the fixing bolt 90 to the first operating portion 96E. In other words, in the radial direction of the fixing bolt 90, the first operating portion 96E is positioned radially outward from the second operating portions 98B1, 98B2. In other words, when viewed in the axial direction of the axis 90E, the first operating portion 96E is positioned outer than the second operating portions 98B1, 98B2 with respect to the axis 90E. Furthermore, if the distance from the axis 90E of the fixing bolt 90 to the tip of the second operating part 98B1 is L1 and the distance from the axis 90E of the fixing bolt 90 to the tip of the second operating part 98B2 is L2, then L1 > L2 (see the enlarged view of part a in FIG. 2). If the vertical distance between the axis 90E of the fixing bolt 90 and the upper surface of the base 20 when the circular saw body 30 is in the initial position is L3, then L3 > L1 (see the enlarged view of part a in FIG. 2). That is, even when the second operating lever 98 is rotated when the circular saw body 30 is in the initial position, the second operating parts 98B1, 98B2 are configured so as not to interfere with the base 20. The second operating part 98B2 is located closer to the axis 90E than the first operating part 96E, and corresponds to the second operating part of the present invention, similar to the second operating part 98B1. The second operating part 98B2 is an operating part that is located at a different position in the rotation direction about the axis 90E relative to the second operating part 98B1, and corresponds to the third operating part in the present invention.

[0065] Furthermore, one second operating portion 98B1 extends from the lever attachment portion 98A to the opposite side to the lever arm portion 96B of the first operating lever 96 (see FIG. 2). The other second operating portion 98B2 is disposed on one side in the rotation direction of the second operating portion 98B1 when viewed from the left side, and is disposed between the second operating portion 98B1 and the lever arm portion 96B. Specifically, the angle between the pair of second operating portions 98B1, 98B2 is set to be equal to or greater than 90 degrees and equal to or less than 180 degrees.

[0066] When the fixing device 92 is in the released state, one second operating portion 98B1 extends downward from the lever mounting portion 98A and is positioned below the axis 90E of the fixing bolt 90 and rearward of the first operating portion 96E of the first operating lever 96 (see the second operating lever 98 indicated by the solid line and the two-dot chain line in FIG. 3). When the fixing device 92 is in the released state, the other second operating portion 98B2 extends upward from the lever mounting portion 98A and is positioned above the axis 90E of the fixing bolt 90 and rearward of the first operating portion 96E (see the second operating lever 98 indicated by the solid line and the two-dot chain line in FIG. 3).

[0067] The operation lever biasing spring 104 is configured as a metal leaf spring. The operation lever biasing spring 104 is formed in a generally elongated plate shape with its thickness in the left-right direction and extending in the front-rear direction. The front end of the operation lever biasing spring 104 is configured as a spring fixing portion 104A, and a fixing hole 104B is formed through the spring fixing portion 104A. The spring fixing portion 104A is disposed adjacent to the left side of a fixing boss 34D of the saw cover portion 34 and is fastened and fixed to the fixing boss 34D by a spring fixing screw 106. Specifically, the spring fixing screw 106 is inserted into the fixing hole 104B and threadedly engaged with the fixing boss 34D, fastening and fixing the operation lever biasing spring 104 to the saw cover portion 34.

[0068] The rear end of the operating lever biasing spring 104 is configured as a mounting portion 104C, which is formed in a substantially annular plate shape. The mounting portion 104C is mounted on the fixture 92. Specifically, the mounting portion 104C is fitted onto the fixture 92 so that the mounting portion 104C is disposed between the flange portion 92B of the fixture 92 and the first operating lever 96.

[0069] Furthermore, when the fixing device 92 is in the released state, the mounting portion 104C is mounted on the fixing device 92 with the operation lever biasing spring 104 elastically deformed to the right. As a result, the operation lever biasing spring 104 biases the first operating lever 96 to the left, and the lever engaging portion 96A of the first operating lever 96 abuts against the E-ring 94. In other words, the biasing force of the operation lever biasing spring 104 to the left is applied directly to the first operating lever 96 and also to the fixing device 92 via the E-ring 94. Then, by rotating the first operating lever 96 and transitioning the fixing device 92 from the released state to the fixed state against the biasing force of the operation lever biasing spring 104, the circular saw body 30 is fixed to the base 20.

[0070] (Operations and Effects) Next, the operations and effects of this embodiment will be described while explaining a method for adjusting the position of the guide member 62 and a method for adjusting the protrusion amount of the circular saw blade 12.

[0071] (Method of adjusting the position of the guide member 62) When the guide mechanism 60 is in a non-operating state, the guide member 62 is fixed to the base 20 by the guide fixing screw 66. Furthermore, the switching lever 71 of the adjustment mechanism 70 is positioned in the retracted position, and the lower end of the roller shaft 74 is fitted into the fitting hole 20H of the base 20. When adjusting the left-right position of the guide member 62 using the adjustment mechanism 70, the fixed state of the guide member 62 by the guide fixing screw 66 is released.

[0072] Then, the operator grips the knob 74A of the roller shaft 74 of the roller unit 73 and lifts the roller unit 73 upward against the biasing force of the shaft biasing spring 77. This disengages the roller shaft 74 from the base 20, allowing the switching lever 71 to rotate. The switching lever 71 is also biased toward the adjustment position by the lever biasing spring 76. Therefore, the biasing force of the lever biasing spring 76 rotates the switching lever 71 to the adjustment position, and the pressing portion 75B of the roller 75 is pressed against the rear surface of the guide member 62.

[0073] In this state, the worker rotates knob 74A of roller unit 73. As a result, frictional force is generated between roller 75 and guide member 62, and the rotational force input by the worker is transmitted to guide member 62, causing guide member 62 to move in the left-right direction relative to base 20. As a result, the left-right position of guide member 62 is adjusted.

[0074] After adjusting the position of the guide member 62, the guide member 62 is fixed by the guide fixing screw 66. The operator also presses the operation knob portion 71G of the switching lever 71 against the biasing force of the lever biasing spring 76 to rotate the switching lever 71 from the adjustment position to the retracted position. This separates the roller 75 from the guide member 62. When the switching lever 71 is in the retracted position, the biasing force of the shaft biasing spring 77 causes the roller shaft 74 to move downward, and the lower end of the roller shaft 74 fits into the fitting hole 20H of the base 20. This holds the switching lever 71 in the retracted position.

[0075] (Method for Adjusting the Protrusion Amount of the Circular Saw Blade 12) When the circular saw body 30 and the base 20 are connected and fixed by the protrusion adjustment mechanism 80, the fixture 92 presses the link 83 to the right, and the head 90A of the fixing bolt 90 and the flange 92B of the fixture 92 fasten the link 83 and the saw cover 34 from the outside in the left-right direction. When adjusting the protrusion amount of the circular saw blade 12, the first operating portion 96E of the first operating lever 96 is operated to rotate the first operating lever 96 toward the other rotational direction, switching the fixture 92 from the fixed state to the released state. This moves the fixture 92 away from the link 83 to the left, and the fastening of the link 83 by the fixture 92 and the saw cover 34 is released. In this state, the operator holds the handle 40 of the circular saw body 30 with one hand and holds the base 20 with the other hand, and moves the circular saw body 30 relative to the base 20 to adjust the protrusion amount of the circular saw blade 12.

[0076] After adjusting the protrusion amount of the circular saw blade 12 (after determining the position of the base 20 relative to the circular saw body 30), the operator operates one of the second operating parts 98B1, 98B2 of the second operating lever 98 with the other hand to switch the fixing device 92 from the release state to the fixing state, thereby temporarily fixing the circular saw body 30 and the base 20 to a temporary fixed state. Specifically, the fixing device 92 is rotated to one side in the rotation direction. As a result, the first operating part 96E of the first operating lever 96 is positioned diagonally rearward and upward from the fixing bolt 90. In this state, the operator grips the first operating part 96E of the first operating lever 96 and applies a rotational force to the first operating lever 96 to one side in the rotation direction. As a result, the circular saw body 30 and the base 20 are fixed to a permanent fixed state.

[0077] As described above, the guide mechanism 60 of the circular saw 10 includes the guide member 62 connected to the base 20 for left-right movement, and the adjustment mechanism 70 for adjusting the left-right position of the guide member 62. The adjustment mechanism 70 has a roller 75 that contacts the rear surface of the guide member 62. Rotating the roller 75 causes friction between the roller 75 and the guide member 62 to move the guide member 62 left-right. Specifically, the lever-biased spring 76 presses the outer circumferential surface of the roller 75 against the rear surface of the guide member 62, and the guide member 62 moves left-right in conjunction with the rotation of the roller 75. This facilitates the left-right position adjustment of the guide member 62. This improves the ease of adjusting the position of the guide member 62.

[0078] As described above, the lever-biasing spring 76 presses the outer peripheral surface of the roller 75 against the rear surface of the guide member 62. That is, the outer peripheral surface of the roller 75 abuts against the rear surface of the guide member 62 with a predetermined pressing force. Therefore, even if the roller 75 wears, the roller 75 is biased toward the guide member 62 by the lever-biasing spring 76, so that the roller 75 can maintain a good state of being in pressure contact (pressed) against the guide member 62. This improves the durability of the adjustment mechanism 70. Furthermore, because the lever-biasing spring 76 biases the roller 75 toward the guide member 62 (front side), the biasing force of the lever-biasing spring 76 can abut the guide member 62 against the base 20 (the front surfaces of the left guide hole 20E and the right guide hole 20F). This makes it easy to set the parallelism of the guide member 62 in the left-right direction.

[0079] Furthermore, the pressing portion 75B of the roller 75 is made of a rubber material. That is, the pressing portion 75B is made of a material with a higher coefficient of friction than metal. This generates a relatively large frictional force between the roller 75 and the guide member 62, and allows the rotational force input to the roller 75 to be transmitted to the guide member 62. Although the pressing portion 75B is made of a rubber material, it may be made of a material other than rubber as long as it has a higher coefficient of friction than metal.

[0080] In the adjustment mechanism 70, the roller 75 is connected to a switching lever 71. The switching lever 71 is rotatably supported on a rotation shaft 20G of the base 20 and is configured to be switchable between an adjustment position and a retracted position. In the adjustment position, the roller 75 is pressed against the guide member 62, and in the retracted position, the roller 75 is separated rearward from the guide member 62. This allows the roller 75 to be released from its pressed state against the guide member 62 when the adjustment mechanism 70 is not in use. This, for example, simplifies the process of removing the guide member 62 and also prevents deformation of the pressing portion 75B of the roller 75 due to aging or the like.

[0081] Furthermore, in the left-right direction, the roller 75 is disposed between the rotation shaft 20G and the circular saw body 30. This allows the roller 75 to be pressed against the longitudinal center portion of the guide member 62, compared to when the roller 75 is disposed on the opposite side of the rotation shaft 20G from the circular saw body 30. Therefore, the biasing force of the lever biasing spring 76 can be applied to the guide member 62 in a balanced manner.

[0082] Furthermore, roller shaft 74 is rotatably connected to switching lever 71 with the vertical direction as the axial direction, and roller 75 is connected to roller shaft 74 so as not to rotate relative to it. Knob 74A of roller shaft 74 is exposed and operable above switching lever 71. This allows the operator to easily input the operator's operating force (rotational force) to roller 75 by operating knob 74A.

[0083] The roller shaft 74 is connected to the switching lever 71 so as to be movable up and down. When in the retracted position, the lower end of the roller shaft 74 is fitted into the fitting hole 20H in the base 20. This allows the switching lever 71 to be held in the retracted position, maintaining the roller 75 spaced apart from the guide member 62. This configuration makes it possible to reproduce the feel of using a conventional circular saw that does not have a roller 75 (adjustment mechanism 70).

[0084] In addition, a shaft biasing spring 77 is attached to the roller shaft 74, and the shaft biasing spring 77 biases the roller shaft 74 downward. This makes it possible to maintain the switching lever 71 in a good state in the retracted position.

[0085] In the projection amount adjustment mechanism 80, a fixing bolt 90 extending to the left from the saw cover portion 34 of the circular saw body 30 is inserted through a link hole 83A of a link 83 supported on the base 20 so as to be relatively movably inserted therethrough. A fixing device 92 is threaded onto the male thread portion 90D of the fixing bolt 90, and as the fixing device 92 rotates in one direction, the fixing device 92 and the fixing bolt 90 fasten the saw cover portion 34 and the link 83 together. This fixes the circular saw body 30 to the base 20. A first operating lever 96 having a first operating portion 96E and a second operating lever 98 having a pair of second operating portions 98B1, 98B2 are connected to the fixing device 92 so as to be rotatable together. When the fixture 92 is in the fixed state, the first operating part 96E is located behind the axis 90E of the fixing bolt 90, and when the fixture 92 is in the released state (when the first operating lever 96 is in the restricting position), one of the second operating parts 98B1 is located behind and below the axis 90E of the fixing bolt 90. This improves the ease of operation when adjusting the protrusion amount of the circular saw blade 12.

[0086] That is, for example, when the circular saw body 30 is in the initial position, an operator positioned behind the circular saw body 30 can operate the first operating unit 96E to switch the fixing device 92 between the fixed state and the released state. Furthermore, when the circular saw body 30 is displaced upward relative to the base 20 to reduce the amount of protrusion of the circular saw blade 12, for example, the operator operates the first operating unit 96E to switch the fixing device 92 from the fixed state to the released state, as described above. Even if the distance between the fixing bolt 90 and the base 20 becomes longer when the circular saw body 30 is tilted upward relative to the base 20, the second operating unit 98B1 is located between the fixing bolt 90 and the base 20, so the operator can easily access the second operating unit 98B1 with the other hand that is holding the base 20.

[0087] This will be described in more detail with reference to FIG. 4. When adjusting the protrusion amount of the circular saw blade 12, for example, the operator holds the handle portion 40 with his left hand while supporting the rear portion of the base 20 with his right hand to adjust the position of the base 20 relative to the circular saw body 30. The reason for supporting the rear portion of the base 20 is that the left, right, and front sides of the operating levers (first operating lever 96, second operating lever 98) that are to be operated simultaneously are blocked by parts of the circular saw body 30. After completing the position adjustment, the operator needs to change from the released state to the locked state. Therefore, the operator needs to support the base 20 with the fingers of his right hand (e.g., the index finger and middle finger) while operating the operating levers (first operating lever 96, second operating lever 98) with the other fingers (e.g., the thumb). At this time, if the operator tries to operate the second operating part 98B2, there is a risk that the fingers will not be able to reach it because it is located some distance from the rear end of the base 20. Furthermore, even if the finger reaches the second operating part 98B2, the finger will hook and grab the rear end of the second operating part 98B2 and the base 20 (especially when tightening), which will generate a force that brings the second operating lever 98 and the rear end of the base 20 closer together, and there is a risk that the relative position of the circular saw body 30 and the base 20 will change.

[0088] In this embodiment, when the circular saw body 30 is positioned so that the protrusion of the circular saw blade 12 is at its smallest and the first operating lever 96 is in the restricting position (contacting the restricting portion 34E) as shown in FIG. 4, at least a portion of the second operating part 98B1 is positioned rearward and below the axis 90E. In other words, when viewed in the axial direction of the axis 90E, at least a portion of the second operating part 98B1 is positioned within the range of a circle C that passes through the axis 90E and is centered at the rear end of the underside of the base 20. This allows the operator to operate the operating lever from a position close to the rear end of the base 20 that supports it. In particular, when the second operating part 98B1 is operated to lock the second operating lever 98, the second operating lever 98 can be rotated by applying a force F (see FIG. 4) to the second operating part 98B1. However, the second operating lever 98 can also be rotated by a forward component F2 or a downward component F3 of the force F. Therefore, the operator can place the operation lever (second operation lever 98) in the locked state by pushing the second operation part 98B1 forward while supporting the rear end of the base 20. In this manner, in the state shown in FIG. 4 , i.e., when the protrusion is minimal and the first operation lever 96 is in contact with the restricting part 34E, the operator can place the operation lever (second operation lever 98) in the locked state by pushing a part of the operation lever (second operation lever 98) forward. This prevents the aforementioned "grabbing motion" and prevents changes in the relative positions of the circular saw body 30 and the base 20. In particular, when the second operation part 98B1 is rotated clockwise from the state shown in FIG. 4 , the tightening force F is directed further forward, enabling highly accurate temporary locking. Furthermore, because the first operation part 96E is configured to move rearward by operating the second operation part 98B1, temporary locking by the second operation lever 98 and final locking by the first operation lever 96 can be performed while supporting the rear end of the base 20. In this way, by operating the second operating part 98B1, the worker can easily switch the fixing device 92 from the released state to the fixed state. As a result, the workability when adjusting the protrusion amount of the circular saw blade 12 can be improved.

[0089] As described above, the first operating lever 96 having the first operating portion 96E and the second operating lever 98 having the pair of second operating portions 98B1 and 98B2 are connected to the fixing device 92 so as to be rotatable together. That is, the first operating lever 96 having the first operating portion 96E and the second operating lever 98 having the second operating portions 98B1 and 98B2 are configured as separate members. As a result, by appropriately changing the mounting positions of the first operating lever 96 and the second operating lever 98 relative to the fixing device 92, the positions of the first operating portion 96E and the second operating portions 98B1 and 98B2 relative to the fixing bolt 90 can be set to appropriate positions. In other words, the relative position (rotational position) of the second operating lever 98 with respect to the first operating lever 96 can be changed. While the first operating lever 96 can only be fixed in a stepwise position by engaging with the nut portion 92C (polygonal portion) and can transmit high torque, the second operating lever 98 is fixed to the fixture 92 by friction alone, allowing for stepless adjustment of its rotational position. This configuration allows the second operating lever 98 to be fixed in a desired position with low torque (temporary fastening), followed by high torque tightening (full fastening) with the first operating lever 96, improving workability. In other words, because the second operating lever 98's relative position (rotational position) to the first operating lever 96 is changeable, the relative positions of the respective operating parts can be adjusted, allowing for adjustment to an operating position that suits the operator's preferences, for example. While the second operating lever 98's rotational position can be changed within a 360-degree angular range in this embodiment, it may also be configured to allow stepless adjustment only to particularly popular positions. The second operating lever 98's rotational position may also be configured to be stepwise adjustable. Furthermore, this feature of "being able to change the position of the second operating lever 98 relative to the first operating lever 96" can be applied to other working machines besides circular saws as long as the working machine has a movable part that is connected so as to be movable relative to the housing. In this embodiment (circular saw), the base 20 corresponds to the movable part. Examples of applicable working machines include jigsaws and routers that have a base as a movable part, and grinders that have a wheel guard (a member covering the grinding wheel) as a movable part.The above features are applicable to such work machines as a configuration for fixing the position of a movable part relative to a housing.

[0090] The second operating lever 98 has a cylindrical lever attachment portion 98A rotatably supported on the tip portion of the fixture 92, and second operating portions 98B1, 98B2 extending radially outward from the lever attachment portion 98A. The second operating lever 98 is fixed to the fixture 92 by a fixing screw 100 that is threaded into the female thread portion 92A on the tip side of the fixture 92. This makes it possible to fix the second operating lever 98 to the fixture 92 while easily setting the positions of the second operating portions 98B1, 98B2 in the circumferential direction of the fixture 92.

[0091] As described above, the second operating lever 98 has a pair of second operating parts 98B1, 98B2. When the fixing device 92 is in the released state, one of the second operating parts 98B1 is located below the axis 90E of the fixing bolt 90 and rearward of the first operating part 96E, and the other of the second operating parts 98B2 is located above the axis 90E of the fixing bolt 90 and rearward of the first operating part 96E. Therefore, when the circular saw body 30 is in the initial position, the fixing device 92 can be switched from the released state to the fixed state by operating the second operating part 98B2. When the circular saw body 30 is in a tilted position, the fixing device 92 can be switched from the released state to the fixed state by operating the second operating part 98B1. That is, the fixing device 92 can be easily switched from the released state to the fixed state by selecting either the second operating part 98B1 or 98B2 depending on the position of the circular saw body 30. This effectively improves the workability when adjusting the protrusion amount of the circular saw blade 12.

[0092] Furthermore, in the radial direction of the fixing bolt 90, the first operating portion 96E of the first operating lever 96 is disposed radially outward of the second operating portions 98B1, 98B2 of the second operating lever 98. This makes it possible to prevent the overall size of the protrusion amount adjustment mechanism 80 from increasing, and to operate the second operating portions 98B1, 98B2 to put the fixing device 92 in a temporary fixed state, and then operate the first operating portion 96E to put the fixing device 92 in a permanently fixed state.

[0093] (Modification of protrusion amount adjustment mechanism 80) Next, a modification of the protrusion amount adjustment mechanism 80 will be described with reference to Figures 12 and 13. The modification of the protrusion amount adjustment mechanism 80 has the same configuration as this embodiment, except for the following points. In Figures 12 and 13, the same reference numerals are used to designate members that are configured in the same way as this embodiment.

[0094] In this modified example of the protrusion amount adjustment mechanism 80, the second operating lever 98 of the present embodiment is omitted from the circular saw body 30. That is, the axial length of the fixture 92 is set shorter than that of the present embodiment, and only the first operating lever 96 is connected to the fixture 92 so as to be rotatable integrally therewith.

[0095] Furthermore, in a modified example of the protrusion amount adjustment mechanism 80, a support mechanism 110 that supports the link 83 is provided on the base 20 instead of the support plate 84 and the link support shaft 85. The support mechanism 110 is configured to include a support plate 112 as a support member, a link bolt 114 as a support shaft, a link nut 116 as a rotating tool, and a second operating lever 118.

[0096] The support plate 112 is formed in a generally U-shaped plate shape that is open to the front in a plan view. Specifically, the support plate 112 includes a plate main body 112A whose plate thickness direction is the front-rear direction, a first clamping portion 112B extending forward from the left end of the plate main body 112A, and a second clamping portion 112C extending forward from the right end of the plate main body 112A. The plate main body 112A is connected to the base 20, and the lower end 83B of the link 83 is disposed between the first clamping portion 112B and the second clamping portion 112C. The lower end 83B of the link 83 is formed in a cylindrical shape with the axial direction extending in the left-right direction and protrudes leftward compared to the rest of the link 83.

[0097] The link bolt 114 is formed in a generally cylindrical shape with its axial direction extending in the left-right direction. The link bolt 114 is bridged between the first clamping portion 112B and the second clamping portion 112C of the support plate 112. The link bolt 114 is inserted through the lower end portion 83B of the link 83 to rotatably support the lower end portion 83B. The right end portion of the link bolt 114 engages with the second clamping portion 112C, and the link bolt 114 is connected to the support plate 112 so as not to rotate relative to the support plate 112.

[0098] A flange portion 114A is formed at the right end of the link bolt 114, and the flange portion 114A is disposed adjacent to the right side of the second clamping portion 112C of the support plate 112. This restricts movement of the link 83 to the left. The left end of the link bolt 114 protrudes leftward beyond the first clamping portion 112B of the support plate 112, and a male thread portion 114B is formed on the outer periphery of this left end.

[0099] Link nut 116 is formed in a generally cylindrical shape with its axial direction extending in the left-right direction, and a female thread portion 116A is formed on the inner periphery of link nut 116. Female thread portion 116A of link nut 116 is screwed onto male thread portion 114B of link bolt 114, and link nut 116 is attached to the left end of link bolt 114. When viewed from the left side, by rotating link nut 116 clockwise (one side in the rotation direction), link nut 116 is displaced to the right, and link nut 116 and flange portion 114A of link bolt 114 tighten first clamping portion 112B and second clamping portion 112C from the outside in the left-right direction, so that first clamping portion 112B and second clamping portion 112C clamp lower end 83B of link 83 from both the left and right sides. This prevents link 83 from rotating about the axis of link bolt 114 (hereinafter, this state of support mechanism 110 is referred to as the blocked state). On the other hand, when support mechanism 110 is in the blocked state, by rotating link nut 116 counterclockwise (the other side of the rotation direction), the blocked state of support mechanism 110 is released, and rotation of link 83 about the axis of link bolt 114 is permitted (hereinafter, this state of support mechanism 110 is referred to as the permitted state).

[0100] A flange portion 116B that protrudes radially outward is formed at the right end of link nut 116. A nut portion 116C is formed on link nut 116 to the left of flange portion 116B, and the outer shape of nut portion 116C is formed in a regular hexagonal shape.

[0101] The second operating lever 118 is configured similarly to the first operating lever 96. That is, the second operating lever 118 is formed in a generally elongated plate shape with its thickness extending in the left-right direction. The second operating lever 118 includes a lever engaging portion 118A that forms one end of the second operating lever 118, and a lever arm portion 118B that extends from the lever engaging portion 118A. An engaging hole 118C is formed through the lever engaging portion 118A, and the inner periphery of the engaging hole 118C is formed in a zigzag shape. The nut portion 116C of the link nut 116 is inserted into the engaging hole 118C of the second operating lever 118 from the right side, and the second operating lever 118 is attached to the link nut 116 so as to be rotatable integrally therewith. Furthermore, a second operating part 118D is provided at the tip of the lever arm part 118B, and an operator grips the second operating part 118D to input an operating force (rotational force) to the second operating part 118D.

[0102] As a result, the support mechanism 110 is switched between a blocked state and a permitted state by rotating the second operating lever 118. When the support mechanism 110 is in the blocked state, the second operating part 118D is disposed diagonally upward and rearward relative to the link bolt 114 (see FIGS. 12(A) and 12(B)). The second operating lever 118 is disposed to the left of the first operating lever 96 so that the first operating lever 96 and the second operating lever 118 do not interfere with each other. Furthermore, the E-ring 120 engaged with the link nut 116 restricts the second operating lever 118 from moving to the left.

[0103] When adjusting the amount of protrusion of the circular saw blade 12 using the modified extension adjustment mechanism 80, the support mechanism 110 is set to the permitted state. Then, the first operating part 96E of the first operating lever 96 is operated to rotate the first operating lever 96 toward the other rotational direction, switching the fixing device 92 from the fixed state to the released state. This moves the fixing device 92 away from the link 83 to the left, and the fixing device 92 and the saw cover part 34 no longer clamp the link 83. In this state, the operator holds the handle part 40 of the circular saw body 30 with one hand and the base 20 with the other hand, and moves the circular saw body 30 relative to the base 20 to adjust the amount of protrusion of the circular saw blade 12.

[0104] After adjusting the protrusion of the circular saw blade 12, the operator operates the second operating part 118D of the second operating lever 118 with the other hand to switch the support mechanism 110 from the permitted state to the blocked state. This prevents the link 83 from rotating around the axis of the link bolt 114. Furthermore, when viewed from the left and right, the center of the arc-shaped link 83 is offset from the axis of the main body support shaft 82. That is, the rotation path of the fixing bolt 90 around the main body support shaft 82 is offset from the link hole 83A of the link 83. Therefore, the rotation of the link 83 around the axis of the link bolt 114 is prevented, thereby prohibiting the fixing bolt 90 from moving relative to the link 83. Therefore, when the support mechanism 110 is in the blocked state, the circular saw body 30 can be temporarily fixed to the base 20. In this state, the operator grips the first operating part 96E of the first operating lever 96 and applies a rotational force to the first operating lever 96 in one direction. As a result, the circular saw body 30 and the base 20 are in a fully fixed state.

[0105] As described above, in the modified example of the projection amount adjustment mechanism 80, the second operating lever 118 (second operating part 118D) for temporarily fixing the circular saw body 30 relative to the base 20 is provided on the base 20 side. In other words, even when the circular saw body 30 is placed in the tilted position, the position of the second operating lever 118 relative to the base 20 does not change. This allows the other hand holding the base 20 to easily access the second operating part 118D, even when the circular saw body 30 is significantly displaced upward relative to the base 20. Therefore, even in the modified example of the projection amount adjustment mechanism 80, the operability when adjusting the projection amount of the circular saw blade 12 can be improved.

[0106] In the adjustment mechanism 70 of the present embodiment, the switching lever 71 is rotatably connected to the base 20, and the roller 75 is switched between the retracted position and the adjustment position by changing the position of the switching lever 71, but the method for switching the position of the roller 75 is not limited to this. For example, the switching lever 71 may be slidably connected to the base 20, and the roller 75 may be switched between the retracted position and the adjustment position by changing the position of the switching lever 71.

[0107] Furthermore, in the adjustment mechanism 70 of this embodiment, the switching lever 71 has the switching operation part 71F and the operation knob part 71G, but the switching lever 71 may omit the switching operation part 71F and the operation knob part 71G.

[0108] Furthermore, in the protrusion amount adjustment mechanism 80 of this embodiment, the first operating lever 96 and the second operating lever 98 are configured as separate bodies, but the first operating lever 96 and the second operating lever 98 may also be configured as a single integral part. For example, as shown in Fig. 14, an operating lever 108 that is a single part having a first operating portion 96E and second operating portions 98B1 and 98B2 may be connected to the fixing device 92 so as to be rotatable integrally with it. Furthermore, the second operating portions 98B1 and 98B2 were configured as part of a single part and inseparable, but they may also be configured as separate parts that allow for fine position adjustment. [Explanation of symbols]

[0109] 10...Circular saw (working machine), 12...Circular saw blade (tip tool), 20B...Through-through portion, 30...Circular saw body (body), 80...Protrusion amount adjustment mechanism, 83...Link, 90...Fixing bolt (fixing shaft), 90C...Latching portion, 90D...Male thread portion, 90E...Axis of fixing bolt (axis of fixed shaft), 92...Fixing device, 92A...Female thread portion, 96...First operating lever (lever, first lever), 96E...First operating portion, 98...Second operating Lever (lever, second lever), 98A... lever mounting portion (mounting portion), 98B1... second operating portion, 98B2... second operating portion, 100... fixing screw (fastening member), 110... support mechanism, 112... support plate (support member), 112B... first clamping portion, 112C... second clamping portion, 114... link bolt (support shaft), 116... link nut (rotating device), 118... second operating lever (lever, second lever)

Claims

1. a housing that accommodates a motor; and a movable part that is connected to the housing so as to be movable relative to the housing; a first lever supported by the housing and rotatable about a rotation axis extending in a predetermined direction, and a second lever rotatable about the rotation axis; the second lever is configured so that a relative rotational position about the rotation axis line with respect to the first lever can be changed, and so that the first lever can be rotated by rotating the second lever, By operating the first lever, it is possible to switch between a fixed state in which the position of the movable part with respect to the housing is fixed and a released state in which the fixed state is released and the housing is movable relative to the movable part, The work machine is configured so that the fixed state and the released state can be switched also by operating the second lever.

2. The movable part is a base having an insertion portion and sliding on the workpiece during processing; the housing is provided above the base, and has a tool bit that is inserted into the insertion portion and partially protrudes downward from the base, a projection amount adjustment mechanism that connects the base and the housing so as to be relatively movable relative to each other and is configured to adjust the amount of projection of the tool bit from the base; 2. The work machine according to claim 1, wherein the protrusion amount adjustment mechanism includes the first lever and the second lever, as well as a fixed shaft extending from the housing, and a link supported by the base and having a link hole through which the fixed shaft is inserted.

3. The first lever has a first operating part extending in a direction perpendicular to the predetermined direction, the second lever has a second operating portion extending in a direction perpendicular to the predetermined direction, 2. The work machine according to claim 1, wherein the rotational position of the second operating unit can be set to a position different from that of the first operating unit, or can be set to a position similar to that of the first operating unit, by adjusting the rotational position of the second lever relative to the first lever.

4. A work machine as described in claim 2, which has a fixing device that is connected to the first lever so that it can rotate integrally with the first lever, and the fixed state and the released state are switched between by rotating the fixing device.

5. A male thread portion is formed at the tip of the fixed shaft, 5. The work machine according to claim 4, wherein the fixture is formed in a cylindrical shape having a female thread portion on its inner periphery, and the male thread portion is threadedly engaged with the female thread portion on the base end side of the fixture.

6. The second operating unit is provided in a pair, 4. The work machine according to claim 3, wherein, in the released state, one of the second operating parts is positioned below the rotation center position of the first lever and to the rear of the first operating part, and the other of the second operating parts is positioned above the rotation center position of the first lever and to the rear of the first operating part.

7. A work machine as described in Claim 3, wherein the first operating part is positioned further outward than the second operating part in a direction perpendicular to the specified direction relative to the rotation center position of the first lever.

8. A work machine as described in claim 4 or claim 5, wherein the second lever is attached to the fixing device and is configured so that the angle relative to the fixing device can be changed continuously.

9. The first lever has a first operating part extending in a direction perpendicular to the predetermined direction, the second lever has a second operating portion extending in a direction perpendicular to the predetermined direction, 2. The work machine according to claim 1, wherein when the first operating part is located in front of and above the rotation center position of the first lever, the second operating part is located behind and below the rotation center position of the first lever.

10. The movable part is a base having an insertion portion and sliding on the workpiece during processing, the housing is provided above the base, and has a tool bit that is inserted into the insertion portion and partially protrudes downward from the base, a projection amount adjustment mechanism that connects the base and the housing so as to be relatively movable relative to each other and is configured to adjust the amount of projection of the tool bit from the base; the housing has a restricting portion that restricts rotation of the first lever, the first lever is brought into the released state by being rotated from the fixed state in one direction around the predetermined direction, and in the released state, the rotation in one direction around the predetermined direction from the restricted position is restricted by the restricting portion, 4. The work machine according to claim 3, wherein when the housing is positioned at a position where the amount of protrusion is smallest and the first lever is in the restricted position, at least a portion of the second operating part is positioned within a circle that passes through the rotation center position of the first lever and is centered at the rear end of the underside of the base, as viewed in the specified direction.

11. A work machine as described in claim 1, wherein the second lever is capable of rotating integrally with the first lever by restricting changes in its relative rotational position about the rotation axis with respect to the first lever by a fixed member that contacts the second lever, and wherein the relative rotational position about the rotation axis with respect to the first lever can be changed by keeping the fixed member and the second lever out of contact.

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