WO2024095828A1

WO2024095828A1 - Work machine

Info

Publication number: WO2024095828A1
Application number: PCT/JP2023/038345
Authority: WO
Inventors: 朴人伊勢
Original assignee: 工機ホールディングス株式会社
Priority date: 2022-11-01
Filing date: 2023-10-24
Publication date: 2024-05-10

Abstract

The present invention suppresses a deterioration in work efficiency. In a tilting mechanism 60 of a circular saw 10, a front tilting mechanism section 70 includes a front tilting plate 72 connected to a circular saw body 20 and a front guide 71 for guiding rotation of the front tilting plate 72, and a rear tilting mechanism section 80 includes a rear tilting plate 82 connected to the circular saw body 20 and a rear guide 81 for guiding rotation of the rear tilting plate 82. When the circular saw body 20 is tilted (rotated) from an upright position to a tilting position, the circular saw body 20 as a whole is separated from the base 12 along a side surface of a circular saw blade 14 by the front guide 71 and the rear guide 81. Thus, even when the circular saw body 20 is tilted from the upright position, downward displacement of a washer member 16 for connecting the circular saw blade 14 to an output shaft 44 can be suppressed.

Description

Work Machine

The present invention relates to a work machine.

In the portable cutting machine (working machine) described in the following Patent Document 1, the main body having a circular saw blade is supported by a tilting mechanism so as to be rotatable around a connecting member (a rotation axis extending in the front-rear direction) on a base. This allows the operator to tilt the main body relative to the base to change the angle of the cutting surface of the workpiece. In addition, the following Patent Document 2 discloses a working machine that is compatible with a member (guide rail) that assists in linear cutting. The working machine in Patent Document 2 also has a tilting mechanism similar to that of the working machine in Patent Document 1, but does not have a rotation axis as a mechanical configuration, but has a virtual rotation axis (tilting axis V). The reason why the tilting axis V in Patent Document 2 is virtual is because it is necessary to set the tilting axis below the bottom surface of the base to accommodate cutting with a guide rail. In addition, in the working machine in Patent Document 2, the position of the virtual tilting axis is aligned with the end of the guide rail to improve workability.

International Publication No. 2017/187894 JP 2017-196853 A

When the main body is tilted, the washer member, which acts as a holding member that holds the circular saw blade to the main body, is displaced downwards depending on the position of the central axis of rotation when the main body is tilted. For this reason, in order to prevent the workpiece and the washer member from interfering with each other when the main body is tilted, it was necessary to space the washer member somewhat above the workpiece when the main body is not tilted (at a right angle). However, in this case, the cutting depth into the workpiece when in the non-tilted state is reduced, which may reduce the operability of the portable cutting machine.

On the other hand, by setting the rotation center axis when the main body is tilted to the left side of the circular saw blade when viewed from the front, the washer member is displaced upward when the main body is tilted, so that interference between the workpiece and the washer member when the main body is tilted can be suppressed. However, even in this case, the cutting depth into the workpiece may be reduced, and the operability of the portable cutting machine may be reduced. In addition, some working machines are configured to be tiltable in the reverse direction, and in this case, the washer member is displaced downward in the tilted state, but is displaced upward in the reverse tilted state. Therefore, the cutting depth is reduced during reverse tilting. Another issue is that tilting requires relative movement between the base and the main body, and the base and the main body must be shaped so as not to hinder this relative movement. For example, in working machines, there are cases where additional functions such as a lighting device and a blower mechanism are used to improve operability, but when attempting to place these additional functions in a place with high effectiveness, the placement of the functions may hinder the tilting (relative movement) or the mechanical structure of the tilting mechanism, so it may be necessary to place them in a place with low effectiveness. As a result, workability is reduced. Another issue is that in a configuration in which tilting is achieved by the movement of a guide shaft inside a guide groove as described in Cited Document 1, if there is excessive contact between the guide groove and the guide shaft, smooth tilting becomes difficult, which reduces workability.

The present invention takes into consideration the above facts and aims to provide a work machine that can suppress a decrease in workability.

One or more embodiments of the present invention include a main body having a motor and an output shaft whose axial direction is in the left-right direction and which rotates when driven by the motor, a circular saw blade connected to the output shaft so as to be rotatable together with the output shaft and extending in the front-rear direction, a washer member for holding the circular saw blade on the output shaft, a base disposed below the main body and having an insertion portion through which the circular saw blade is inserted, and a tilting mechanism configured to tilt the main body from a non-tilted state in which the output shaft extends in the left-right direction relative to the base by a predetermined angle to one side in the left-right direction to a tilted state, the tilting mechanism being provided on one of the main body and the base and having a guide portion. The machine has a guide member and a guided part that is provided on the other of the main body and the base, operates inside the guide part, and has its movement guided by the guide part. In both the non-tilted state and the tilted state, the circular saw blade is configured to overlap with a virtual axis extending in the front-rear direction at a position below the washer member, and in a virtual state in which the main body in the non-tilted state is rotated by the specified angle around the virtual axis, at least a part of the washer member is positioned below the bottom surface of the base, and when transitioning from the non-tilted state to the tilted state, the tilting mechanism operates the washer member above the bottom surface of the base.

One or more embodiments of the present invention are a work machine in which at least a portion of the washer member is located inside the insertion portion in at least one of the non-tilted state and the tilted state.

In one or more embodiments of the present invention, the guide portion is formed in an arc shape, and the radius of curvature of the guide portion is set to be large at least in a portion of the work machine.

One or more embodiments of the present invention are a work machine in which a pair of guide portions are formed on the guide member, with one guide portion being positioned radially outside the other guide portion.

In one or more embodiments of the present invention, the guided portion includes a pair of guide shafts with the axial direction being the front-to-rear direction, and the guide shafts are movably inserted into the pair of guide portions, respectively, in the work machine.

One or more embodiments of the present invention are a work machine in which the guide shaft is formed into a cylindrical shape.

One or more embodiments of the present invention are a work machine in which a bearing member is provided on the guided portion, and the bearing member is movably inserted into the guide portion.

In one or more embodiments of the present invention, the guide portion and the guided portion are provided in pairs, the pair of guided portions are arranged so as to be spaced apart in a direction perpendicular to the front-to-rear direction, and the bearing member is provided on the side of the pair of guided portions that is located on the outer side at least in the direction perpendicular to the front-to-rear direction.

In one or more embodiments of the present invention, the guide portion and the guided portion are provided in pairs, the guide portion is formed in an arc shape, the guide member is formed with an arc-shaped fixed hole separate from the guide portion, the tilting mechanism has a fixed shaft inserted through the fixed hole and a fixed member provided at the tip of the fixed shaft and operable by an operator, the operator can operate the fixed member to allow or restrict tilting of the main body portion relative to the base, and the fixed hole is configured to be located between the pair of guide portions in a direction perpendicular to the front-rear direction.

In one or more embodiments of the present invention, the tilting mechanism has a regulating member configured to be rotatable about the axis, and the regulating member is configured to guide the movement of the main body so as to allow relative movement in a predetermined direction with respect to the regulating member.

In one or more embodiments of the present invention, the restricting member has a restricting hole formed therein that extends in a direction intersecting the extension direction of the output shaft, and a part of the main body is inserted through the restricting hole, so that the restricting member and the main body engage in the extension direction of the output shaft, thereby restricting the relative movement of the main body with respect to the restricting member in a direction intersecting the predetermined direction.

One or more embodiments of the present invention are a work machine in which the regulating member is made of a material having a higher mechanical strength than the guide member, is configured to be impregnated with a lubricating oil, or is molded by sintering.

One or more embodiments of the present invention are a work machine comprising a main body having a motor and an output shaft that rotates when driven by the motor, a circular saw blade connected to the output shaft so as to rotate integrally with the output shaft, a washer member for holding the circular saw blade on the output shaft, a base disposed below the main body and having an insertion portion through which the circular saw blade is inserted, and a tilting mechanism capable of tilting the main body from a non-tilted state to a tilted state tilted 45 degrees relative to the base, the work machine being configured such that the lower end position of the washer member in the tilted state is at the same position as or higher than the lower end position of the washer member in the non-tilted state.

One or more embodiments of the present invention are a work machine comprising a main body having a motor and an output shaft that rotates when driven by the motor, a circular saw blade connected to the output shaft so as to be rotatable together with the main body, a base disposed below the main body and having an insertion portion through which the circular saw blade is inserted, and a tilting mechanism capable of tilting the main body from a non-tilted state to a tilted state tilted by 45 degrees with respect to the base, the circular saw blade being connected to the output shaft via a washer member, and the intersection point between the circular saw blade and a horizontal plane located below the washer member and parallel to the bottom surface of the base is configured to be in substantially the same position when the main body is in the non-tilted state as when the main body is in the tilted state, and the difference in the vertical direction between the bottom end position of the washer member in the non-tilted state and the bottom end position of the washer member in the tilted state is configured to be equal to or less than the vertical distance between the bottom end of the washer member in the non-tilted state and the bottom surface of the base.

One or more embodiments of the present invention are a working machine comprising a main body having a motor and an output shaft that rotates when driven by the motor, a circular saw blade connected to the output shaft so as to be rotatable together with the main body, a base disposed below the main body and having an insertion portion through which the circular saw blade is inserted, and a tilting mechanism capable of tilting the main body from a non-tilted state to a tilted state relative to the base, the circular saw blade being connected to the output shaft via a washer member, and configured such that the intersection point between the circular saw blade and a horizontal plane located below the washer member and parallel to the underside of the base is in substantially the same position when the main body is in the non-tilted state as when the main body is in the tilted state, and the lower end of the washer member is configured to move continuously upward or downward when the main body is tilted from the non-tilted state to the tilted state.

According to one or more embodiments of the present invention, it is possible to suppress the deterioration of workability.

1 is a plan view showing a circular saw according to an embodiment of the present invention, as viewed from above. FIG. 2 is a right side view of the circular saw shown in FIG. 1 . 3 is a cross-sectional view (cross-sectional view taken along line 3-3 in FIG. 2) showing the inside of the circular saw shown in FIG. 2 as seen from the front side. 4 is a cross-sectional view seen from the front side, showing a state in which the circular saw body shown in FIG. 3 is tilted to a tilted position. FIG. 2 is a plan view showing the tilt mechanism shown in FIG. 1 . 6 is an exploded perspective view of a front tilting mechanism in the tilting mechanism shown in FIG. 5, as viewed diagonally from the rear left side. FIG. 6 is an exploded perspective view of a front tilting mechanism in the tilting mechanism shown in FIG. 5, as viewed obliquely from the front right side. 6 is an exploded perspective view of a rear tilting mechanism in the tilting mechanism shown in FIG. 5, as viewed from the diagonally front right side. FIG. 9 is a cross-sectional view (cross-sectional view taken along line 9-9 in FIG. 2) showing the inside of the front tilting mechanism shown in FIG. 2 as seen from the rear side. 10 is a cross-sectional view corresponding to FIG. 9 and illustrating the inside of the front tilting mechanism when the circular saw body is tilted to a tilted position. (A) is a cross-sectional view from the front showing the inside of the rear tilting mechanism shown in Figure 2 (cross-sectional view along line 11A-11A in Figure 2), and (B) is a cross-sectional view corresponding to (A) showing the inside of the rear tilting mechanism when the circular saw body is tilted to the tilted position.

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

As shown in Figures 1 and 2, the circular saw 10 is configured as an electric tool for cutting workpieces. The circular saw 10 includes a base 12 and a circular saw body 20 as a main body. The circular saw 10 also has a tilting mechanism 60 that connects the circular saw body 20 to the base 12 so that it can be tilted. Each component of the circular saw 10 will be described below.

(Regarding the base 12) As shown in Figures 1 to 5, the base 12 is made of metal and is formed in a generally rectangular plate shape with the plate thickness direction being the up-down direction and the length direction being the front-rear direction. When cutting with the circular saw 10, the base 12 is placed on the workpiece and moved forward. An insertion portion 12A for arranging the circular saw blade 14 is formed through the right part of the base 12. The insertion portion 12A is formed in a generally rectangular shape with the length direction being the front-rear direction, and is a through hole with a width in the up-down direction. Here, the circular saw blade 14 is formed in a generally circular plate shape with the plate thickness direction being the left-right direction, and the center of the circular saw blade 14 is fixed to the output shaft 44 of the drive mechanism 40 described later so as to be able to rotate together. A part of the circular saw blade 14 is arranged within the insertion portion 12A, and the upper part of the circular saw blade 14 protrudes upward from the base 12, and the lower end part of the circular saw blade 14 protrudes downward from the base 12 (the base lower surface 12C). The base 12 is provided with an engagement portion 12B for accommodating a guide rail as shown in the patent document. In other words, the circular saw 10 is configured to accommodate a guide rail.

(Regarding the circular saw body 20) As shown in Figures 1 to 3, the circular saw body 20 includes a housing 22, a battery 32, and a drive mechanism 40.

(About the housing 22) The housing 22 is made up of multiple housing members, forms the outer shell of the circular saw body 20, and is positioned above the base 12. The housing 22 includes a saw cover 24 that covers the circular saw blade 14, a motor housing 26 that houses the drive mechanism 40 (described below), and a battery holder 28 in which the battery 32 is attached.

The saw cover 24 forms the right end of the housing 22. The saw cover 24 is formed in a roughly semicircular plate shape with its thickness in the left-right direction and a convex shape that is upwardly convex, and is formed in a concave shape that is open downwardly. The upper part of the circular saw blade 14 is housed within and covered by the saw cover 24.

The saw cover 24 is connected to the base 12 by the cutting depth adjustment mechanism 30 via the tilting mechanism 60, which will be described later. Specifically, the front end of the saw cover 24 is connected to the front end of the tilting mechanism 60 by the front connecting mechanism 30A of the cutting depth adjustment mechanism 30, and the rear end of the saw cover 24 is connected to the rear end of the tilting mechanism 60 by the rear connecting mechanism 30B of the cutting depth adjustment mechanism 30. This connects the circular saw body 20 to the base 12. A cover connecting portion 24A is provided on the left side of the saw cover 24. The cover connecting portion 24A is formed in a substantially cylindrical shape with its axial direction in the left-right direction, and protrudes to the left from the saw cover 24.

The motor housing 26 is generally box-shaped and opens to the right. The motor housing 26 is located to the left of the cover connection portion 24A of the saw cover 24 and is fastened to the cover connection portion 24A at a position not shown.

The battery holder 28 extends rearward from the top of the motor housing 26. A battery 32 is attached to the battery holder 28 from the rear, and is disposed below the battery holder 28 and at the rear of the motor housing 26. The battery 32 is electrically connected to a controller (not shown) and a motor 42 of a drive mechanism 40, which will be described later.

A handle portion 28A is provided above the battery holder 28. When viewed from the right side, the handle portion 28A is formed in a roughly U-shape that opens diagonally downward and forward, with the front end of the handle portion 28A connected to the motor housing 26 and the rear end of the handle portion 28A connected to the battery holder 28. A trigger 34 is provided on the handle portion 28A so that it can be pulled. By pulling (pushing) the trigger 34, a switch (not shown) housed inside the handle portion 28A is pressed. This switch is electrically connected to a controller, and a drive mechanism 40 (described later) is activated in response to the operation of the trigger 34.

(Regarding the drive mechanism 40) As shown in FIG. 3, the drive mechanism 40 includes a motor 42 and an output shaft 44. The motor 42 is configured as a brushless motor, is housed in the motor housing 26, and is electrically connected to the controller. The motor 42 has a rotating shaft 42A whose axial direction is in the left-right direction, and the rotating shaft 42A is rotatably supported by a motor bearing (not shown) fixed to the motor housing 26. A pinion gear is formed on the right end of the rotating shaft 42A.

The output shaft 44 has its axial direction in the left-right direction and is disposed below the right end of the rotating shaft 42A and within the cover connecting portion 24A of the saw cover 24. The left end of the output shaft 44 is rotatably supported by a metal bearing 46 fixed to the cover connecting portion 24A, and the left-right middle portion of the output shaft 44 is rotatably supported by a bearing 48 fixed to the cover connecting portion 24A. An output gear 50 is provided at the left-right middle portion of the output shaft 44 so as to be integrally rotatable, and the output gear 50 is connected to the pinion gear of the rotating shaft 42A by a transmission mechanism (not shown).

The center of the circular saw blade 14 is fixed to the right end of the output shaft 44 by a fixing bolt 52. Specifically, the center of the circular saw blade 14 is sandwiched from the outside in the left-right direction by a washer member 16 that serves as a holding member for holding the circular saw blade 14, and the washer member 16 is fastened and fixed to the output shaft 44 by the fixing bolt 52. As a result, when the motor 42 is driven, the output shaft 44 and the circular saw blade 14 are configured to rotate to one side around the axis of the output shaft 44. In addition, the lower end of the washer member 16 is located within the insertion portion 12A of the base 12 (within the vertical width range of the insertion portion 12A).

The lower part of the circular saw blade 14 is covered by a protective cover 54. The protective cover 54 is formed in a generally semicircular shape that is convex downward when viewed from the right side, and is formed in a concave shape that is open upward. The protective cover 54 is connected to the output shaft 44 so as to be rotatable around the axis of the output shaft 44. The protective cover 54 is biased around the axis of the output shaft 44 by a biasing spring (not shown) and is held in the position shown in FIG. 2. During cutting with the circular saw 10, the protective cover 54 rotates around the axis of the output shaft 44 against the biasing force of the biasing spring due to the workpiece, exposing the blade portion of the circular saw blade 14.

(Regarding the tilting mechanism 60) As shown in Figures 1, 2, and 5 to 11, the working machine in this embodiment has a tilting mechanism 60 that changes the relative position of the circular saw body 20 and the base 12 to tilt (tilt) the circular saw blade 14 relative to the base 12. Specifically, the tilting mechanism 60 is configured to allow the circular saw body 20 to rotate between an upright position (non-tilted position, position shown in Figures 1 to 3) and a tilted position tilted approximately 45 degrees to the right from the upright position (position shown in Figure 4). The tilting mechanism 60 is configured to be able to tilt the circular saw body 20 relative to the base 12 so that the position of the axis AL does not change, assuming that the intersection of the circular saw blade 14 (left side) in the non-tilted state (right angle state) and the horizontal plane GB is the axis AL. The underside of the attachable guide rail is configured to be on the same plane as the horizontal plane GB. That is, the axis AL is approximately the same as the position where the circular saw blade 14 intersects with the top surface of the workpiece during cutting using the guide rail. The axis AL is not an axis that actually exists as an object, like the imaginary tilting axis shown in Patent Document 2. In appearance, the tilting mechanism 60 can be said to be a mechanism that rotatably connects the circular saw body 20 to the base 12 around an imaginary (virtual) axis AL (see Figures 9 to 11) that extends in the front-to-rear direction, but the position of the axis AL (the intersection of the circular saw blade 14 and the horizontal plane GB) with respect to the circular saw body 20 changes relatively with tilting (details will be described later).

As shown in FIG. 5, the tilting mechanism 60 is provided on the upper side of the base 12, spanning from the front to the rear. The tilting mechanism 60 includes a front tilting mechanism 70 that constitutes the front end of the tilting mechanism 60, and a rear tilting mechanism 80 that constitutes the rear end of the tilting mechanism 60, and the front tilting mechanism 70 and the rear tilting mechanism 80 are connected so that they operate simultaneously.

(Regarding the front tilting mechanism 70) As shown in Figures 5 to 7, 9, and 10, the front tilting mechanism 70 includes a front guide 71 as a guide member, a front tilting plate 72 as a movable member, and a front link 78 as a regulating member.

(Regarding the front guide 71) The front guide 71 is made of metal (aluminum in this embodiment) and is formed as a generally rectangular plate with its thickness direction in the front-to-rear direction as a whole. A guide fixing portion 71A that protrudes outward in the left-right direction is provided at the lower end of the front guide 71. The front guide 71 is positioned at a distance in front of the saw cover 24, and the guide fixing portion 71A is fastened and fixed to the base 12 by a fixing screw SC1. The top surface of the front guide 71 is curved and inclined upwards towards the right side in a rear view seen from the rear. The axis AL is located below the right part of the front guide 71.

A storage recess 71B is formed on the rear surface of the front guide 71 to accommodate a front link 78, which will be described later. The storage recess 71B is formed in a concave shape that is open to the rear, and extends along the rotation direction of the circular saw body 20 (see the directions of arrows A and B in Figures 9 and 10) when viewed from behind, and is curved and inclined upward as it approaches the right side. The right end of the storage recess 71B is open to the right, and the left end of the storage recess 71B is open diagonally downward to the left.

The rear surface of the front guide 71 is formed with an inner guide groove 71C as a guide groove for guiding the inner guide shaft 73 described later, at the radially inner portion of the storage recess 71B. The inner guide groove 71C is formed in a groove shape that is open to the rear side. When viewed from the rear, the inner guide groove 71C extends in a curved (arcuate) shape along the rotation direction of the circular saw body 20. As will be described in detail later, the inner guide groove 71C is configured so that the curvature (radius of curvature) changes at least in a part. In other words, in the non-tilted state (right angle state) shown in FIG. 9, the radius of curvature of the inner guide groove 71C centered on the axis line AL is set to increase from the lower end (the end on one side in the longitudinal direction, which is also the left end) of the inner guide groove 71C to the upper end (the end on the other side in the longitudinal direction, which is also the right end). The end surface 71C1 of the lower end of the inner guide groove 71C is inclined toward one side in the longitudinal direction of the inner guide groove 71C as it approaches the rear side (the opening side of the inner guide groove 71C).

The rear surface of the front guide 71 is formed with an outer guide groove 71D as a guide groove for guiding the outer guide shaft 74 described later, at the radial outer portion of the accommodation recess 71B and radial outer side of the inner guide groove 71C. The outer guide groove 71D is formed in a groove shape that is open to the rear side. The outer guide groove 71D extends parallel to the inner guide groove 71C when viewed from the rear side. The outer guide groove 71D is curved in a substantially arc shape centered on the axis line AL. As will be described in detail later, the outer guide groove 71D is configured so that the curvature (radius of curvature) changes at least in a part. In other words, the radius of curvature of the outer guide groove 71D centered on the axis line AL is set to increase from the lower end (the end on one side in the longitudinal direction, which is also the left end) of the outer guide groove 71D to the upper end (the end on the other side in the longitudinal direction, which is also the right end). The groove width of the outer guide groove 71D is set to be wider than the groove width of the inner guide groove 71C. Furthermore, the end surface 71D1 of the lower end of the outer guide groove 71D is inclined toward one side in the longitudinal direction of the outer guide groove 71D as it approaches the rear side (the opening side of the outer guide groove 71D).

A fixing hole 71E is formed through the front guide 71 between the inner guide groove 71C and the outer guide groove 71D. The fixing hole 71E is a hole through which a fixing shaft 76, which will be described later, is inserted. When viewed from the rear, the fixing hole 71E extends so as to be parallel to the inner guide groove 71C and the outer guide groove 71D. The radius of curvature of the fixing hole 71E is set to increase from the lower end to the upper end of the fixing hole 71E.

Figures 9 and 10 respectively show point CA1, which is the center position of the outer guide shaft 74, point CB1, which is the center position of the inner guide shaft 73, and point CC1, which is the center position of the fixed shaft 76, in the right-angle state (non-tilted). Similarly, point CA2, which is the center position of the outer guide shaft 74, point CB2, which is the center position of the inner guide shaft 73, and point CC2, which is the center position of the fixed shaft 76, in the tilted state (45-degree tilted state), are respectively shown. Furthermore, arc TA, which is the trajectory of the center position of the outer guide shaft 74, arc TB, which is the trajectory of the center position of the inner guide shaft 73, and arc TC, which is the trajectory of the center position of the fixed shaft 76 are shown. Arcs TA, TB, and TC each correspond to a partial arc of a specified ellipse (elliptical arc). The center positions of the outer guide shaft 74, inner guide shaft 73, and fixed shaft 76 move between points CA1, CB1, and CC1 and points CA2, CB2, and CC2, but in Figures 9 and 10, the arcs (TA, TB, and TC) that form the trajectory are drawn overrunning. As shown in the figures, the arc TA is an arc that gradually moves away (radially) from the axis AL. That is, as described above, the arc TA is an arc whose radius of curvature gradually increases (curvature decreases) starting from CA1. The same is true for the arcs TB and TC. The arcs TA, TB, and TC are also lines that connect the center positions in the width direction (radially) of each guide groove (71C, 71D, and 71E).

9 and 10 show points CA', CB', CC', arc TA', TB', and TC' as comparative examples (conventional examples) for points CA2, CB2, CC2, arc TA, arc TB, and arc TC. Points CA', CB', and CC' are the center positions of the outer guide shaft 74, inner guide shaft 73, and fixed shaft 76 in the tilted state when the radius of curvature of each guide groove (71C, 71D, 71E) is constant. Arcs TA', TB', and TC' are the orbits through which the center positions of the outer guide shaft 74, inner guide shaft 73, and fixed shaft 76 pass when the radius of curvature of each guide groove (71C, 71D, 71E) is constant. The arcs TA', TB', and TC' are parallel to each other, and each arc is a part of a perfect circle centered on a predetermined axis AL. Point CA2, which is the end point of the outer guide shaft 74, is located above point CA'. In other words, the position of the guide shaft in the tilted state is located higher than in the past. As shown in the figure, the arcs TA, TB, and TC are longer than the conventional arcs TA', TB', and TC'. Therefore, when the present invention (a configuration in which the guide groove is an arc with a gradually increasing radius of curvature) is adopted, the front guide 71 may become larger than in the past.

Figures 9 and 10 show straight lines L1 and L2 passing through the axis AL. Straight line L1 is inclined at an angle of 45 degrees with respect to the left-right direction (up-down direction). Straight line L2 extends parallel to the up-down direction. In other words, straight lines L1 and L2 intersect at an angle of 45 degrees. When the circular saw body 20 is in an upright position (right angle state), points CA1, CB1, and CC1 are located on straight line L1 when viewed from behind. Also, as shown in the figures, when the circular saw body 20 is in a tilted state (45 degree tilt state), the center positions of the outer guide shaft 74, inner guide shaft 73, and fixed shaft 76, which would conventionally be located on straight line L2, are each shifted to the upper right.

Figure 9 shows the vertical distance S1 between the lower end of the washer member 16 and the lower surface of the base 12 in the upright position (right angle state). Furthermore, Figure 10 shows the vertical distance S2 between the lower end of the washer member 16 and the lower surface of the base 12 in the tilted state (45 degree tilted state) in addition to the distance S1. Furthermore, both Figures 9 and 10 show the axis AL (the intersection of the circular saw blade 14 and the horizontal plane GB) corresponding to each state, and Figure 10 shows the position of the axis AL relative to the circular saw body 20 in the state of Figure 9 as AL'. Also, Figure 9 shows the position of the washer member 16 in a state (virtual state) in which the circular saw body 20 in the upright position (upright state) is tilted 45 degrees around the axis AL relative to the base 12 as a virtual position 16' by a dotted line. In other words, the virtual position 16' is the position of the washer member 16 in the tilted state when the virtual tilt axis is fixed as in the conventional case. In other words, the virtual position 16' is the position of the washer member 16 in the tilted state when the radius of curvature of each guide groove (71C, 71D, 71E) is constant. That is, in this embodiment, the cutting depth in the upright position is set to such an extent that in the conventional configuration (with the virtual tilting axis fixed), at least a part of the washer member 16 is located below the base underside 12C in the tilted state. Also, in this embodiment, in order to accommodate cutting using a guide rail, the intersection point (axis AL) between the circular saw blade 14 and the horizontal plane GB is not changed between the upright position and the tilted position. In other words, in both the upright position and the tilted position, a part of the circular saw blade 14 is configured to pass through the virtual axis (axis AL). Therefore, in the tilted position, the intersection point between the circular saw blade 14 and the base underside 12C when viewed from behind moves in the direction in which the circular saw body 20 tilts (to the right). Due to the change in the radius of curvature of each of the guide grooves (71C, 71D, 71E) described above, as the circular saw body 20 moves from the upright position (non-tilted state) to the tilted position, it moves away from the base 12 along the planar direction of the circular saw blade 14. As a result, the position of the axis AL relative to the circular saw body 20 changes between the upright position and the tilted position. Specifically, as shown in FIG. 10, the axis AL at the tilted position is located farther away from the washer member 16 (the center of the circular saw blade 14) than the axis AL' at the upright position. Therefore, the cutting depth changes between the upright position and the tilted position. In the configuration shown in FIGS. 9 and 10, the cutting depth is large in the upright position and small in the tilted position. That is, according to this embodiment, the cutting depth is changed by guiding the guide shaft into the guide groove due to the shape of the guide groove. Specifically, the cutting depth is shallowed (the amount of protrusion of the circular saw blade 14 protruding downward from the base underside 12C is reduced) according to the tilting operation by adjusting the radius of curvature of the guide groove. In this embodiment, the distance S2 is configured to be larger than the distance S1. Specifically, the distance S1 is 1 mm and the distance S2 is 1.5 mm. Therefore, it is 0.5 mm larger than the distance S1. In other words, the amount of movement of the lower end position of the washer member 16 accompanying the tilting is 0.5 mm, which is less than the distance S1. In this way, the lower end of the washer member 16 is gradually moved upward from the lower surface 12C of the base 12 as the washer member 16 tilts. Note that the lower end position of the washer member 16 is configured not to move downward when transitioning from the upright state to the tilted state. That is, in this embodiment, the lower end position of the washer member 16 is configured to move continuously upward when transitioning from the upright state to the tilted state. It is desirable that the amount of movement of the lower end position of the washer member 16 accompanying tilting be equal to or less than the vertical distance (distance S1) between the lower end position of the washer member 16 in the upright position (non-tilted state) and the base underside 12C. By configuring in this way, as shown in virtual position 16' in Figure 9, even if the cutting depth in the upright state is increased to such an extent that part of the washer member 16 is positioned below the base underside 12C during tilting in the conventional configuration (fixed virtual shaft), the washer member 16 can be operated in a range above the base underside 12C.

(Regarding the front tilting plate 72) The front tilting plate 72 is made of metal (aluminum in this embodiment). The front tilting plate 72 is formed as a generally long plate with its thickness in the front-to-rear direction and extending along the rotation direction of the circular saw body 20, and is disposed adjacent to the rear side of the front guide 71. A plate fixing portion 72A is formed in the approximate center of the rear surface of the front tilting plate 72, which is raised one step toward the rear, and the plate fixing portion 72A is fastened and fixed to the front connecting mechanism 30A of the cutting depth adjustment mechanism 30. In this way, the front tilting plate 72 is connected to the front end of the circular saw body 20.

The inner guide shaft 73 is provided as a guide shaft at a position corresponding to the inner guide groove 71C of the front guide 71 on the radial inner part of the front tilting plate 72. The inner guide shaft 73 is formed in a substantially cylindrical shape with the axial direction being the front-rear direction, and the rear end of the inner guide shaft 73 is pressed into the shaft hole 72B formed in the front tilting plate 72, so that the inner guide shaft 73 protrudes forward from the front tilting plate 72. The diameter of the inner guide shaft 73 is set slightly smaller than the groove width of the inner guide groove 71C, and the front end of the inner guide shaft 73 is movably inserted into the inner guide groove 71C and is disposed within the lower end of the inner guide groove 71C. As a result, when the circular saw body 20 rotates between the upright position and the tilted position, the inner guide shaft 73 is guided by the inner guide groove 71C. In addition, when the circular saw body 20 is in the tilted position, the inner guide shaft 73 is disposed within the upper end of the inner guide groove 71C.

An outer guide shaft 74 is provided as a guide shaft at a position corresponding to the outer guide groove 71D in the front guide 71 on the radial outer portion of the front tilting plate 72. The outer guide shaft 74 is formed in a substantially cylindrical shape with the axial direction being the front-rear direction, and has the same shape as the inner guide shaft 73. The rear end of the outer guide shaft 74 is pressed into an axial hole 72C formed in the front tilting plate 72, and the outer guide shaft 74 protrudes forward from the front tilting plate 72. A cylindrical bearing member 75 is provided at the front end of the outer guide shaft 74, and the bearing member 75 is configured as a ball bearing. The diameter of the bearing member 75 is set slightly smaller than the groove width of the outer guide groove 71D, and the bearing member 75 is movably inserted into the outer guide groove 71D and is disposed in the lower end of the outer guide groove 71D. As a result, when the circular saw body 20 rotates between the upright position and the tilted position, the outer guide shaft 74 (bearing member 75) is guided by the outer guide groove 71D. Furthermore, when the circular saw body 20 is in the tilted position, the outer guide shaft 74 (bearing member 75) is disposed within the upper end of the outer guide groove 71D. The outer guide shaft 74 and the inner guide shaft 73 are guide shafts in the present invention and are an example of a guided portion.

The front tilt plate 72 is provided with a fixed shaft 76 between the inner guide shaft 73 and the outer guide shaft 74. The fixed shaft 76 is provided between the inner guide shaft 73 and the outer guide shaft 74 in the radial direction (direction perpendicular to the front-rear direction) centered on the axis line AL. The fixed shaft 76 is formed in a substantially cylindrical shape with the front-rear direction as the axial direction, and the rear end of the fixed shaft 76 is connected to the front tilt plate 72 so as not to rotate relative to the front tilt plate 72, and the fixed shaft 76 protrudes forward from the front tilt plate 72. The diameter of the fixed shaft 76 is set smaller than the width dimension of the fixed hole 71E, and the fixed shaft 76 passes through the lower end of the fixed hole 71E, and the front end of the fixed shaft 76 protrudes forward from the front guide 71. The front end of the fixed shaft 76 is provided with a fixed lever 77 (see Figures 1 and 2) as a substantially elongated fixed member, and one end of the fixed lever 77 is screwed into a threaded portion formed on the outer periphery of the front end of the fixed shaft 76. As a result, by tightening the fixing lever 77 to the front guide 71, the front tilt plate 72 is fixed to the front guide 71.

Furthermore, a plate connection part 72D is integrally provided at the lower end of the left part of the front tilt plate 72 to connect the front tilt plate 72 to a rear tilt plate 82 of the rear tilt mechanism part 80 (described later). In other words, the front tilt plate 72 and the rear tilt plate 82 are composed of a single inseparable member. The plate connection part 72D is formed in a generally elongated plate shape with the thickness direction being the up-down direction and the longitudinal direction being the front-to-rear direction, and extends rearward from the front tilt plate 72.

(Regarding the front link 78) The front link 78 is made of sintered metal (iron in this embodiment), and the front link 78 is impregnated with lubricating oil. In other words, the front link 78 is made of a material with higher mechanical strength than the front guide 71. The front link 78 is formed in a plate shape with the plate thickness direction being in the front-to-rear direction and extending along the rotation direction of the circular saw body 20, and is movably accommodated in the accommodating recess 71B of the front guide 71. Specifically, the radial outer surface of the front link 78 is arranged close to the radial inner side of the upper inner surface of the accommodating recess 71B, and the radial inner surface of the front link 78 is arranged close to the radial outer side of the lower inner surface of the accommodating recess 71B. Here, the upper inner surface of the accommodating recess 71B and the lower inner surface of the accommodating recess 71B are in a form equivalent to a partial arc of a perfect circle centered on the axis AL (the intersection of the circular saw blade 14 and the horizontal plane GB). As a result, the front link 78 is connected to the front guide 71 so that it can rotate around the axis AL, and when the front tilt mechanism 70 is activated, the front link 78 rotates around the axis AL while being guided by the accommodation recess 71B. For the purposes of durability and lubrication, the front link 78 is made of sintered metal, but if these problems are minor, it may be made of another material such as resin.

A pair of link holes 78A are formed through the front link 78 as restriction holes. The link holes 78A are holes that penetrate in the front-rear direction. The link holes 78A are formed as elongated holes (extending in a direction that intersects with the extension direction of the output shaft 44) with the vertical direction (direction that intersects with the extension direction of the output shaft 44) as the longitudinal direction. The width dimension of the link holes 78A is set to be slightly larger than the diameters of the inner guide shaft 73 and the outer guide shaft 74. The link holes 78A are disposed at positions corresponding to the inner guide shaft 73 and the outer guide shaft 74, respectively, and the front-rear middle parts of the inner guide shaft 73 and the outer guide shaft 74 are inserted into the lower part of the link holes 78A. As a result, the front link 78 is connected to the front tilt plate 72 with the inner guide shaft 73 and the outer guide shaft 74 engaged with the link holes 78A in the left-right direction. As described above, when the circular saw body 20 rotates between the upright position and the tilted position, the circular saw body 20 is configured to move toward and away from the base 12 along the side of the circular saw blade 14, so the inner guide shaft 73 and the outer guide shaft 74 move relatively within the link hole 78A in the longitudinal direction of the link hole 78A.

A through hole 78B is formed between a pair of link holes 78A in the front link 78, and the through hole 78B is formed as an elongated hole with the vertical direction as the longitudinal direction. The width dimension of the through hole 78B is set to be larger than the diameter of the fixed shaft 76. The through hole 78B is disposed at a position corresponding to the fixed shaft 76, and the middle part of the fixed shaft 76 in the front-rear direction is inserted through the lower part of the through hole 78B. When the circular saw body 20 rotates between the upright position and the tilted position, the fixed shaft 76 moves relative to the through hole 78B in the longitudinal direction of the through hole 78B.

(Regarding the rear tilting mechanism 80) As shown in Figures 5, 8, and 11, the rear tilting mechanism 80 is disposed on the rear side of the saw cover 24, and is configured such that the front tilting mechanism 70 is inverted in the front-to-rear direction. That is, the rear tilting mechanism 80 includes a rear guide 81 as a guide member, a rear tilting plate 82 as a movable member, and a rear link 88 as a regulating member. The rear tilting plate 82 is disposed in front of the rear guide 81, and the rear link 88 is disposed between the rear guide 81 and the rear tilting plate 82.

(Regarding the rear guide 81) The rear guide 81 is made of metal (aluminum in this embodiment) and is configured in substantially the same way as the front guide 71 inverted in the front-to-rear direction. That is, the rear guide 81 is formed in the shape of a plate whose thickness direction is in the front-to-rear direction, and a guide fixing portion 81A provided at the lower end of the rear guide 81 is fastened and fixed to the base 12 by a fixing screw SC2. A storage recess 81B is formed in the front surface of the rear guide 81, and the storage recess 81B extends along the rotation direction of the circular saw body 20 when viewed from the front side.

In addition, the front surface of the rear guide 81 is formed with an inner guide groove 81C and an outer guide groove 81D as guide grooves that are open to the front side. The inner guide groove 81C and the outer guide groove 81D are curved in an approximately arc shape centered on the axis AL in the upright state, similar to the inner guide groove 71C and the outer guide groove 71D. The radius of curvature of each of the inner guide groove 81C and the outer guide groove 81D is set to increase from the lower end (one end on one side in the longitudinal direction, which is also the left end) to the upper end (the other end on the other side in the longitudinal direction, which is also the right end). The end face 81C1 of the lower end of the inner guide groove 81C is inclined toward one side in the longitudinal direction of the inner guide groove 81C toward the front side (the opening side of the inner guide groove 81C), and the end face 81C2 of the upper end of the inner guide groove 81C is inclined toward the other side in the longitudinal direction of the inner guide groove 81C toward the front side. Additionally, the end surface 81D1 of the lower end of the outer guide groove 81D is inclined toward one side in the longitudinal direction of the outer guide groove 81D as it approaches the front side (the opening side of the outer guide groove 81D). In addition, in the rear guide 81, the groove widths of the inner guide groove 81C and the outer guide groove 81D are set to the same dimension.

Furthermore, a fixing hole 81E is formed through the front surface of the rear guide 81. The fixing hole 81E is disposed between the inner guide groove 81C and the outer guide groove 81D, and like the fixing hole 71E, is curved in a substantially arc shape centered on the axis AL so as to be parallel to the inner guide groove 81C and the outer guide groove 81D in a front view, and the radius of curvature of the fixing hole 81E is set to increase from the lower end to the upper end. The characteristics and effects of the radius of curvature of the guide groove in the rear guide 81 are similar to those of the front guide 71, so details are omitted.

(Regarding the rear tilt plate 82) The rear tilt plate 82, like the rear guide 81, is made of metal (aluminum in this embodiment). The rear tilt plate 82 is formed in a generally trapezoidal plate shape with the plate thickness direction being in the front-to-rear direction. A plate fixing portion 82A is formed at the lower end of the front surface of the rear tilt plate 82, which is raised one step forward, and the plate fixing portion 82A is fastened and fixed to the rear connecting mechanism 30B of the cutting depth adjustment mechanism 30. In this way, the rear tilt plate 82 is connected to the rear end of the circular saw body 20.

The rear tilt plate 82 is provided with an inner guide shaft 83 as a guide shaft, an outer guide shaft 84 as a guide shaft, and a fixed shaft 86, similar to the front tilt plate 72, and the inner guide shaft 83, the outer guide shaft 84, and the fixed shaft 86 protrude rearward from the rear tilt plate 82. The inner guide shaft 83 and the outer guide shaft 84 have the same shape as the inner guide shaft 73 and the outer guide shaft 74 of the front tilt plate 72. The inner guide shaft 83 is press-fitted into the shaft hole 82B formed in the rear tilt plate 82, and the rear end of the inner guide shaft 83 is movably inserted into the inner guide groove 81C and is disposed in the lower end of the inner guide groove 81C. The outer guide shaft 84 is press-fitted into the shaft hole 82C formed in the rear tilt plate 82, and the rear end of the outer guide shaft 84 is movably inserted into the outer guide groove 81D and is disposed in the lower end of the outer guide groove 81D. In addition, when the circular saw body 20 is in the tilted position, the inner guide shaft 83 is disposed at the upper end of the inner guide groove 81C, and the outer guide shaft 84 is disposed at the upper end of the outer guide groove 81D. The outer guide shaft 84 and the inner guide shaft 83 are guide shafts in the present invention, and are an example of a guided portion.

The fixed shaft 86 is inserted through the lower end of the fixed hole 81E, and the rear end of the fixed shaft 86 protrudes rearward from the rear guide 81. A fixed knob 87 (see Figures 1 and 2) is provided at the rear end of the fixed shaft 86 as a fixing member, and the fixed knob 87 is screwed into a threaded portion formed on the outer periphery of the rear end of the fixed shaft 86. As a result, by tightening the fixed knob 87 to the rear guide 81, the rear tilt plate 82 is fixed to the rear guide 81.

The plate fixing portion 82A of the rear tilt plate 82 protrudes to the left from the rear tilt plate 82, and the rear end of the plate connecting portion 72D of the front tilt plate 72 is connected to the plate fixing portion 82A. This connects the rear tilt plate 82 to the front tilt plate 72.

(Regarding the rear link 88) The rear link 88, like the front link 78, is made of sintered metal (iron in this embodiment), and is impregnated with lubricating oil. The rear link 88 is formed in a plate shape with its thickness direction in the front-to-rear direction and extending along the rotation direction of the circular saw body 20, and is movably housed in the accommodation recess 81B of the rear guide 81. That is, like the front link 78, the rear link 88 is connected to the rear guide 81 so as to be rotatable about the axis AL, and when the rear tilting mechanism 80 is operated, the rear link 88 rotates around the axis AL while being guided by the accommodation recess 81B.

The rear link 88, like the front link 78, has a pair of link holes 88A and an insertion hole 88B formed therethrough as restriction holes, and the link hole 88A and the insertion hole 88B are formed as elongated holes with the vertical direction as the longitudinal direction. The link holes 88A are arranged at positions corresponding to the inner guide shaft 83 and the outer guide shaft 84 of the rear tilt plate 82, respectively, and the front-rear middle parts of the inner guide shaft 83 and the outer guide shaft 84 are inserted through the lower part of the link hole 88A. As a result, the rear link 88 is connected to the rear tilt plate 82 with the inner guide shaft 83 and the outer guide shaft 84 engaged with the link hole 88A in the left-right direction. The insertion hole 88B is arranged at a position corresponding to the fixed shaft 86, and the front-rear middle part of the fixed shaft 86 is inserted through the lower part of the insertion hole 88B.

Here, as shown in Figures 9 to 11, the axis AL is located below the base 12, and the position of the axis AL in the left-right direction is approximately the same as the position of the circular saw blade 14 (washer member 16) in the upright position (see Figure 9). As described above, the radius of curvature of the inner guide groove 71C and the outer guide groove 71D (inner guide groove 81C and outer guide groove 81D) of the front guide 71 (rear guide 81) is set to increase from the lower end to the upper end. Furthermore, the inner guide shaft 73 (inner guide shaft 83) is disposed at the lower end of the inner guide groove 71C (inner guide groove 81C), and the outer guide shaft 74 (outer guide shaft 84) is disposed at the lower end of the outer guide groove 71D (outer guide groove 81D). When the circular saw body 20 is tilted from the upright position to the tilted position by the tilting mechanism 60, the inner guide shaft 73 (inner guide shaft 83) moves to the upper end along the inner guide groove 71C (inner guide groove 81C), and the outer guide shaft 74 (outer guide shaft 84) moves to the upper end along the outer guide groove 71D (outer guide groove 81D). Therefore, when the circular saw body 20 is tilted from the upright position to the tilted position, the circular saw body 20 is set to move upward relative to the base 12. The radii of curvature of the inner guide groove 71C and outer guide groove 71D of the front guide 71 and the radii of curvature of the inner guide groove 81C and outer guide groove 81D of the rear guide 81 are set so that the amount of relative upward movement of the circular saw body 20 with respect to the base 12 by the front tilting mechanism 70 and the amount of relative upward movement of the circular saw body 20 with respect to the base 12 by the rear tilting mechanism 80 are the same amount.

More specifically, in the upright position, as described above, the lower end of the washer member 16 for connecting the circular saw blade 14 to the output shaft 44 is located within the insertion portion 12A of the base 12 and above the axis AL (see Figures 3 and 9). The radii of curvature of the inner guide groove 71C and the outer guide groove 71D of the front guide 71 and the inner guide groove 81C and the outer guide groove 81D of the rear guide 81 are set so that the lower end of the washer member 16 is displaced to the right within the insertion portion 12A of the base 12 when the tilting mechanism 60 rotates the circular saw body 20 from the upright position to the tilted position (see Figures 4 and 10). In other words, when the tilting mechanism 60 rotates the circular saw body 20 from the upright position to the tilted position, the circular saw body 20 moves upward relative to the base 12 so that the vertical position of the lower end of the washer member 16 does not change downward (so that the washer member 16 does not protrude below the base 12).

(Actions and Effects) Next, we will explain the actions and effects of this embodiment.

In the circular saw 10 configured as described above, when the circular saw body 20 is in the upright position, the circular saw blade 14 is arranged with the left-right direction being the thickness direction of the workpiece. Therefore, when cutting with the circular saw body 20 in the upright position, the cut surface of the workpiece is formed along a plane perpendicular to the left-right direction.

When the cutting surface of the workpiece is to be inclined, the tilting mechanism 60 tilts the circular saw body 20 from the upright position to the tilted position. For example, when the cutting surface of the workpiece is to be inclined at 45 degrees, the tilting mechanism 60 tilts the circular saw body 20 to the tilted position (45 degree inclined position). Specifically, in the front tilting mechanism 70, the fixed lever 77 is rotated to release the clamping state of the fixed lever 77 to the front guide 71, and in the rear tilting mechanism 80, the fixed knob 87 is rotated to release the clamping state of the fixed knob 87 to the rear guide 81. This allows the circular saw body 20 to tilt (move) to the tilted position.

Then, the operator tilts the circular saw body 20 from the upright position toward the tilted position. This causes the tilting mechanism 60 to rotate the circular saw body 20 so as to tilt to the right. Specifically, the inner guide shaft 73 of the front tilting plate 72 moves from the lower end to the upper end along the inner guide groove 71C of the front guide 71, and the outer guide shaft 74 of the front tilting plate 72 moves from the lower end to the upper end along the outer guide groove 71D of the front guide 71. Furthermore, the inner guide shaft 83 of the rear tilting plate 82 moves from the lower end to the upper end along the inner guide groove 81C of the rear guide 81, and the outer guide shaft 84 of the rear tilting plate 82 moves from the lower end to the upper end along the outer guide groove 81D of the rear guide 81. In the front tilting mechanism 70, the inner guide shaft 73 reaches the upper end of the inner guide groove 71C, and the outer guide shaft 74 reaches the upper end of the outer guide groove 71D. In the rear tilting mechanism 80, the inner guide shaft 83 reaches the upper end of the inner guide groove 81C, and the outer guide shaft 84 reaches the upper end of the outer guide groove 81D, so that the circular saw body 20 is placed in the tilted position. When the circular saw body 20 is tilted from the upright position to the tilted position, the fixed shaft 76 is placed at the upper end of the fixed hole 71E of the front guide 71, and the fixed shaft 86 is placed at the upper end of the fixed hole 81E of the rear guide 81. In this state, the fixed lever 77 is rotated to tighten the fixed lever 77 to the front guide 71, and the fixed knob 87 is rotated to tighten the fixed knob 87 to the rear guide 81, so that the circular saw body 20 is fixed to the base 12 (connected so as not to move relative to the base 12).

However, in a tilting mechanism in which the rotation during tilting is positioned below the washer member 16 (bottom left), the washer member 16 is displaced diagonally downward to the right when the circular saw body 20 rotates from the upright position to the tilted position. For this reason, in the past, it was necessary to avoid interference between the washer member 16 and the workpiece by positioning the circular saw body 2 sufficiently above the workpiece so that the washer member would not protrude below the base during tilting, which could result in reduced workability.

Here, in the tilting mechanism 60 of the circular saw 10, the front tilting mechanism 70 of the tilting mechanism 60 is configured to include a front tilting plate 72 connected to the circular saw body 20 and a front guide 71 that guides the rotation of the front tilting plate 72. Furthermore, the rear tilting mechanism 80 of the tilting mechanism 60 is configured to include a rear tilting plate 82 connected to the circular saw body 20 and a rear guide 81 that guides the rotation of the rear tilting plate 82. The front tilting plate 72 and the rear tilting plate 82 are configured not to move relative to the circular saw body 20 when the circular saw body 20 tilts. When the circular saw body 20 tilts (rotates) from the upright position to the tilted position, the front guide 71 and the rear guide 81 move the circular saw body 20 away from the base 12 along the side of the circular saw blade 14 as a whole. As a result, the cutting depth becomes shallower (the amount of protrusion of the circular saw blade 14 protruding downward from the bottom surface 12C of the base is reduced). This prevents the washer member 16 for connecting the circular saw blade 14 to the output shaft 44 from being displaced downward even when the circular saw body 20 is tilted from the upright position. Specifically, the lower end of the washer member 16 is located inside the insertion portion 12A of the base 12 at the upright position, tilted position, and a predetermined position between the upright position and the tilted position of the circular saw body 20. As a result, the washer member 16 is prevented from protruding below the base 12 while preventing a decrease in the cutting depth of the circular saw blade 14. Therefore, a decrease in the workability of the circular saw 10 can be prevented.

The front guide 71 has an inner guide groove 71C and an outer guide groove 71D that guide the rotation of the front tilt plate 72, and the rear guide 81 has an inner guide groove 81C and an outer guide groove 81D that guide the rotation of the rear tilt plate 82. The inner guide groove 71C (inner guide groove 81C) and the outer guide groove 71D (outer guide groove 81D) are formed in an arc shape centered on the axis AL when viewed from the front-rear direction, and are inclined upward as they move toward the right. The inner guide shaft 73 (inner guide shaft 83) is inserted into the lower end of the inner guide groove 71C (inner guide groove 81C), and the outer guide shaft 74 (outer guide shaft 84) is inserted into the lower end of the outer guide groove 71D (outer guide groove 81D). The radius of curvature of the inner guide groove 71C (inner guide groove 81C) and the outer guide groove 71D (outer guide groove 81D) is set to increase from the lower end to the upper end. This allows the circular saw body 20 to be moved upward relative to the base 12 while rotating the circular saw body 20 from the upright position to the tilted position with a simple configuration. In other words, the above configuration allows the amount of movement of the lower end position of the washer member 16 that moves with the tilting to be controlled, and the protrusion of a part of the washer member 16 downward from the base 12 to be suppressed. In other words, the length (amount) by which the circular saw blade 14 protrudes from the base lower surface 12C, that is, the change in the cutting depth, can be controlled. In particular, in this embodiment, the amount of vertical movement of the lower end of the washer member 16 caused by the tilting of the circular saw body 20 is configured to be equal to or less than the vertical distance between the lower end of the washer member 16 and the base lower surface 12C when the circular saw body 20 is in the non-tilted position. Specifically, the amount of vertical movement of the lower end of the washer member 16 is set to 0.5 mm, and the distance S1 is set to 1.0 mm. This allows the washer member 16 to be suitably suppressed from contacting the workpiece. When applying the present invention, if the purpose is to ensure the cutting depth in the upright position, the lower end position of the washer member 16 in the tilted state may be configured to be located at the same position as or higher than the lower end position of the washer member 16 in the upright state (non-tilted state). By making the lower end positions of the washer member 16 in the tilted state and the upright state the same, it is possible to suppress unnecessary reduction in the cutting depth. In this embodiment, since cutting using a guide rail is assumed, the position of the axis AL is set at a position below the base lower surface 12C by a predetermined distance, but the present invention is also applicable to circular saws that do not consider a guide rail. For example, the position of the axis AL may be at a position overlapping with the base lower surface 12C, and in this case, in cutting in a manner in which a guide rail is not used (the base 12 is slid directly on the workpiece), it is possible to configure so that the cutting position of the upper surface of the workpiece is not changed even if the workpiece is tilted. In other words, the horizontal plane GB and the base lower surface 12C may be set to be located on the same plane. The present invention works particularly well in a configuration in which the axis AL is located below the washer 16 (the holding member for the circular saw blade 14).

Note that the curvature radius of the guide groove is configured to increase from the lower end to the upper end, but the present invention is not limited to this. For example, in the case of the above-mentioned reverse tilting, the washer member moves upward and the cutting depth decreases, so in the case of reverse tilting, the tendency of change may be reversed to ensure the cutting depth. In addition, in order to optimally arrange the auxiliary functions (illumination device and blower mechanism), the movement of the main body during tilting can be controlled by adjusting the curvature radius of the guide groove. In addition, in the case of the above-mentioned embodiment, there is a risk that the inclined guide parts (front guide 71, rear guide 81) will become large in exchange for ensuring the cutting depth, but it is also possible to make the inclined guide parts (front guide 71, rear guide 81) small by reversing the change in the curvature radius. In this case, although the lower end position of the washer member 16 moves continuously downward with tilting, in addition to the above-mentioned effect of miniaturization, the amount of left-right movement of the washer member 16 with tilting can also be suppressed. In other words, the effect of the present invention is not limited to ensuring the cutting depth. In addition, in the present embodiment, the guide groove is provided on the base 12 side and the guide shaft is provided on the circular saw body 20 side, but this relationship may be reversed, and the guide groove may be provided on the circular saw body 20 side and the guide shaft on the base 12 side. The guide groove is a groove shape with one side in the front-rear direction closed, but it may be a through hole. Although the washer member 16 serving as a washer has been described as a member for holding the circular saw blade 14, the present invention is not limited to a washer, and any member for holding the circular saw blade 14 may be used. That is, in the present invention, it is sufficient to configure the holding member for holding the circular saw blade 14 to adjust the vertical movement amount during tilting. In addition, in this specification, the washer 16 (holding member) has been described as an example of a member that may be located below the base lower surface 12C during tilting, but other members that move during tilting may be the subject of the description. For example, depending on the shape, parts of the fixing bolt 52 and the saw cover 24 may be located below the washer 16 when tilted, and parts of the motor housing 26 and battery 32 located on the left side of the circular saw body 20 move downward when tilting backwards, so care must be taken to ensure that these do not protrude below the base underside 12C or hit the base 12 when tilted.

As described above, the front guide 71 has an inner guide groove 71C and an outer guide groove 71D, and the rear guide 81 has an inner guide groove 81C and an outer guide groove 81D. That is, the front tilting mechanism 70 and the rear tilting mechanism 80 guide the rotation of the circular saw body 20 with two guide grooves. Therefore, the front tilting plate 72 and the rear tilting plate 82 can be well guided when they rotate.

In addition, in the front tilting mechanism 70, the cylindrical inner guide shaft 73 is movably inserted into the inner guide groove 71C, and the inner guide groove 71C guides the movement of the inner guide shaft 73. In addition, in the rear tilting mechanism 80, the cylindrical inner guide shaft 83 (outer guide shaft 84) is movably inserted into the inner guide groove 81C (outer guide groove 81D), and the inner guide groove 81C (outer guide groove 81D) guides the movement of the inner guide shaft 83 (outer guide shaft 84). As a result, when the tilting mechanism 60 is operated, these guide shafts come into line contact with the inner surfaces of the corresponding guide grooves and are guided by these guide grooves. Therefore, the sliding resistance during operation of the tilting mechanism 60 can be reduced, and the tilting mechanism 60 can be operated smoothly.

Furthermore, in the front tilting mechanism 70, a bearing member 75 configured as a ball bearing (rolling bearing) is provided at the tip of the outer guide shaft 74, and the bearing member 75 is movably inserted into the outer guide groove 71D. This makes it possible to further reduce the sliding resistance during operation of the front tilting mechanism 70, and to operate the front tilting mechanism 70 more smoothly. The invention in which a bearing member is provided on the guide shaft can also be applied to a configuration in which the radius of curvature of the arc-shaped guide portion is constant.

In the front tilting mechanism 70, the fixed shaft 76 extends forward from the front tilting plate 72 and passes through the fixing hole 71E of the front guide 71, with the front end of the fixed shaft 76 protruding forward from the front guide 71. A fixed lever 77 is screwed to the front end of the fixed shaft 76. As a result, by tightening the fixed lever 77 to the front guide 71, the circular saw body 20 can be fixed to the base 12 (connected so as not to move relative to the base 12). Similarly, in the rear tilting mechanism 80, the fixed shaft 86 extends rearward from the rear tilting plate 82 and passes through the fixing hole 81E of the rear guide 81, with the rear end of the fixed shaft 86 protruding rearward from the rear guide 81. A fixed knob 87 is screwed to the rear end of the fixed shaft 86. As a result, by tightening the fixed knob 87 to the rear guide 81, the circular saw body 20 can be fixed to the base 12 (connected so as not to move relative to the base 12).

In the front tilting mechanism 70, the front tilting plate 72 is disposed on the rear side of the front guide 71, and the inner guide groove 71C and the outer guide groove 71D of the front guide 71 are formed as grooves that are open to the rear side. In the rear tilting mechanism 80, the rear tilting plate 82 is disposed on the front side of the rear guide 81, and the inner guide groove 81C and the outer guide groove 81D of the rear guide 81 are formed as grooves that are open to the front side. This makes it possible to prevent chips generated during cutting from entering the inner guide groove 71C, the outer guide groove 71D, the inner guide groove 81C, and the outer guide groove 81D. Therefore, the tilting mechanism 60 can be operated well.

The front tilting mechanism 70 also has a front link 78, which is connected to the front guide 71 so as to be rotatable around the axis AL. The front link 78 has a pair of elongated link holes 78A with the vertical direction as the longitudinal direction, and the inner guide shaft 73 and the outer guide shaft 74 are inserted through the link holes 78A, so that the inner guide shaft 73 and the outer guide shaft 74 are engaged with the link holes 78A in the left-right direction. Similarly, the rear tilting mechanism 80 has a rear link 88, which is connected to the rear guide 81 so as to be rotatable around the axis AL. The rear link 88 has a pair of elongated link holes 88A with the vertical direction as the longitudinal direction, and the inner guide shaft 83 and the outer guide shaft 84 are inserted through the link holes 88A, so that the inner guide shaft 83 and the outer guide shaft 84 are engaged with the link holes 88A in the left-right direction. That is, the guide shafts (73, 74, 83, 84) in this embodiment are guided in tilting by two means: a guide portion (guide groove) provided on the base 12, and a regulating member (front link 78, rear link 88) that rotates relative to the base 12 when the circular saw body 20 is tilted. As a result, the guide shafts are able to move in the extension direction of the arc of the guide portion while the regulating member restricts the circular saw body 20 from moving relative to the regulating member (front link 78, rear link 88) in the extension direction of the output shaft 44. In other words, the circular saw body 20 is supported by the regulating member so that the circular saw body 20 can tilt relative to the base 12 by moving relative to the regulating member (front link 78, rear link 88) that rotates relative to the base 12 when the circular saw body 20 is tilted in a direction perpendicular to the extension direction of the output shaft 44. This prevents the guide shafts (73, 74, 83, 84) from moving in the direction of extension of the output shaft 44 within the arc-shaped guide portion during tilting, and prevents excessive contact between the guide shafts and the guide portion. Therefore, when the tilting mechanism 60 is operating, the front tilting plate 72 (and rear tilting plate 82) can be rotated smoothly, allowing the circular saw body 20 to be tilted even more smoothly.

In other words, if the front link 78 is omitted from the front tilting mechanism 70, the movement of the inner guide shaft 73 and the outer guide shaft 74 in the inner guide groove 71C and the outer guide groove 71D (particularly in the extension direction of the output shaft 44) will not be restricted. This is also true for the rear tilting mechanism 80. For this reason, when the tilting mechanism 60 is in operation, for example, if the circular saw body 20 moves relative to the base 12 in the extension direction of the output shaft 44, or if there is a left-right positional deviation between the front tilting plate 72 and the rear tilting plate 82, a part of the guide shaft (73, 74, 83, 84) may move in a direction intersecting the arc (guide direction) within the guide portion, causing excessive contact between the inner surface of the guide portion and the guide shaft, and the circular saw body 20 may not tilt smoothly.

In response to this, the front tilting mechanism 70 (rear tilting mechanism 80) is provided with a front link 78 (rear link 88) that engages with the front tilting plate 72 (rear tilting plate 82) in the left-right direction (extension direction of the output shaft 44). Therefore, the front link 78 (rear link 88) can restrict the movement of the inner guide shaft 73 and the outer guide shaft 74 (inner guide shaft 83 and outer guide shaft 84) in the longitudinal direction (mainly the left-right direction) of the inner guide groove 71C and the outer guide groove 71D (inner guide groove 81C and outer guide groove 81D). Moreover, the front link 78 (rear link 88) is connected to the front guide 71 (rear guide 81) so as to be rotatable around the axis AL. Therefore, the inner guide shaft 73 and the outer guide shaft 74 (the inner guide shaft 83 and the outer guide shaft 84) move along the longitudinal direction of the inner guide groove 71C and the outer guide groove 71D (the inner guide groove 81C and the outer guide groove 81D) in accordance with the amount of left-right displacement of the front guide 71 (the rear guide 81) rotating about the axis line AL. As a result, it is possible to suppress the relative movement of the circular saw body 20 in the direction of the output shaft 44 with respect to the base 12 and the left-right positional deviation between the front tilting plate 72 and the rear tilting plate 82 when the tilting mechanism 60 is operated. Therefore, it is possible to improve the rotation of the front tilting plate 72 and the rear tilting plate 82 and to make the tilting operation of the circular saw body 20 even smoother when the tilting mechanism 60 is operated. The invention, which uses restricting members (front link 78, rear link 88) to restrict the movement of the guide shaft, can also be applied to a configuration in which the radius of curvature of the arc-shaped guide section is constant, and is particularly effective in a circular saw that has a tilting mechanism with a virtual tilt axis.

The front link 78 (rear link 88) is made of sintered metal made of iron, and the front guide 71 (rear guide 81) is made of aluminum. In other words, the mechanical strength of the front link 78 (rear link 88) is configured to be higher than the mechanical strength of the front guide 71 (rear guide 81). This improves the wear resistance of the front link 78 (rear link 88) and also improves the durability of the tilting mechanism 60.

The front link 78 (rear link 88) is impregnated with lubricating oil. This further improves the wear resistance of the front link 78 (rear link 88) and the durability of the tilting mechanism 60. In particular, the lubricating oil makes the sliding between the link hole 78A (link hole 88A) and the inner guide shaft 73 and the outer guide shaft 74 (the inner guide shaft 83 and the outer guide shaft 84) smooth, so that deterioration due to wear is suppressed and deterioration of operation due to excessive friction resistance is suppressed. In addition, the front link 78 (rear link 88) is interposed between the circular saw body 20 (front tilt plate 72) and the base 12 (front guide 11), and has the effect of reducing resistance (sliding resistance) when they move relative to each other. In the above, an invention that can improve cutting performance by changing the radius of curvature of the guide groove has been described, but the sliding resistance reduction mechanism by the front link 78 (rear link 88) can be applied independently of the invention of changing the radius of curvature of the guide groove.

10...Circular saw (working machine), 12...Base, 12A...Through-hole, 14...Circular saw blade, 16...Washer member, 20...Circular saw body (main body), 42...Motor, 44...Output shaft, 60...Tilting mechanism, 71...Front guide (guide member), 71C...Inner guide groove (guide groove), 71D...Outer guide groove (guide groove), 71E...Fixed hole, 72...Front tilt plate (movable member), 73...Inner guide shaft (guide shaft), 74...Outer guide shaft (guide shaft), 75...Bearing member, 76 ...Fixed shaft, 77...Fixed lever (fixed member), 78...Front link (regulating member), 81...Rear guide (guide member), 81C...Inner guide groove (guide groove), 81D...Outer guide groove (guide groove), 81E...Fixed hole, 82...Rear tilt plate (movable member), 83...Inner guide shaft (guide shaft), 84...Outer guide shaft (guide shaft), 86...Fixed shaft, 87...Fixed knob (fixed member), 88...Rear link (regulating member), 88A...Link hole (regulating hole), AL...Axis line

Claims

A main body portion having a motor and an output shaft whose axial direction is in the left-right direction and which rotates by being driven by the motor;
a circular saw blade connected to the output shaft so as to be rotatable together with the output shaft and extending in a front-rear direction;
a washer member for holding the circular saw blade on the output shaft;
a base disposed below the main body and having an insertion portion through which the circular saw blade is inserted;
a tilting mechanism configured to be able to tilt the main body from a non-tilted state in which the output shaft extends in the left-right direction relative to the base by a predetermined angle to one side in the left-right direction to set the main body in a tilted state;
Equipped with
the tilting mechanism includes a guide member provided on one of the main body portion and the base and having a guide portion, and a guided portion provided on the other of the main body portion and the base, operating inside the guide portion, and having its movement guided by the guide portion;
In either the non-tilted state or the tilted state, a virtual axis extending in the front-rear direction is overlapped with the circular saw blade at a position below the washer member,
a tilt mechanism for tilting the washer member above the bottom surface of the base when the main body is rotated a predetermined angle around the virtual axis in the non-tilted state, the tilt mechanism causing the washer member to operate above the bottom surface of the base when transitioning from the non-tilted state to the tilted state.
The work machine according to claim 1, wherein at least a portion of the washer member is located inside the insertion portion in at least one of the non-tilted state and the tilted state.
The work machine according to claim 1 or claim 2, wherein the guide portion is formed in an arc shape, and the radius of curvature of the guide portion is set to be large at least in a portion.
The work machine according to claim 3, wherein the guide member is formed with a pair of guide portions, one of which is positioned radially outward of the other guide portion.
The work machine according to claim 4, wherein the guided portion includes a pair of guide shafts whose axial direction is the front-rear direction, and the guide shafts are movably inserted into the pair of guide portions, respectively.
The work machine according to claim 5, wherein the guide shaft is formed into a cylindrical shape.
The work machine according to claim 1, wherein a bearing member is provided on the guided portion, and the bearing member is movably inserted into the guide portion.
The guide portion and the guided portion are provided in pairs,
The pair of guided portions are arranged to be spaced apart from each other in a direction perpendicular to the front-rear direction,
The work machine according to claim 7 , wherein the bearing member is provided on one of the pair of guided portions that is positioned on an outer side at least in a direction perpendicular to the front-rear direction.
The guide portion and the guided portion are provided in pairs,
The guide portion is formed in an arc shape,
The guide member is provided with a fixing hole having an arc shape, separate from the guide portion.
The tilt mechanism includes a fixed shaft that is inserted through the fixed hole, and a fixed member that is provided at a tip of the fixed shaft and can be operated by an operator.
An operator can allow or restrict tilting of the main body portion relative to the base by operating the fixing member,
The work machine according to claim 1 , wherein the fixing hole is configured to be located between the pair of guide portions in a direction perpendicular to the front-rear direction.
the tilt mechanism has a regulating member configured to be rotatable around a front-rear direction,
The work machine according to claim 1 , wherein the regulating member is configured to guide the movement of the main body portion so as to allow relative movement in a predetermined direction with respect to the regulating member.
The work machine according to claim 10, wherein the restricting member has a restricting hole extending in a direction intersecting the extension direction of the output shaft, and a part of the main body is inserted through the restricting hole to engage the restricting member and the main body in the extension direction of the output shaft, thereby restricting the relative movement of the main body in the direction intersecting the predetermined direction with respect to the restricting member.
The regulating member is
The work machine according to claim 10, wherein the work machine is made of a material having a higher mechanical strength than the guide member, is configured to be impregnated with a lubricating oil, or is formed by sintering.
A main body having a motor and an output shaft that is rotated by the driving of the motor;
a circular saw blade connected to the output shaft so as to be integrally rotatable;
a washer member for holding the circular saw blade on the output shaft;
a base disposed below the main body and having an insertion portion through which the circular saw blade is inserted;
a tilting mechanism capable of tilting the main body from a non-tilted state to a tilted state tilted by 45 degrees with respect to the base;
Equipped with
The working machine is configured such that a lower end position of the washer member in the tilted state is located at the same position as or higher than a lower end position of the washer member in the non-tilted state.
A main body having a motor and an output shaft that is rotated by the driving of the motor;
a circular saw blade connected to the output shaft so as to be integrally rotatable;
a base disposed below the main body and having an insertion portion through which the circular saw blade is inserted;
a tilting mechanism capable of tilting the main body from a non-tilted state to a tilted state tilted by 45 degrees with respect to the base;
Equipped with
The circular saw blade is connected to the output shaft via a washer member,
A working machine configured such that the intersection point between the circular saw blade and a horizontal plane located below the washer member and parallel to the underside of the base is at approximately the same position when the main body is in the non-tilted state as when the main body is in the tilted state, and such that the difference in the vertical direction between the lower end position of the washer member in the non-tilted state and the lower end position of the washer member in the tilted state is less than the vertical distance between the lower end position of the washer member in the non-tilted state and the underside of the base.
A main body having a motor and an output shaft that is rotated by the driving of the motor;
a circular saw blade connected to the output shaft so as to be integrally rotatable;
a base disposed below the main body and having an insertion portion through which the circular saw blade is inserted;
a tilting mechanism capable of tilting the main body from a non-tilted state to a tilted state relative to the base;
Equipped with
The circular saw blade is connected to the output shaft via a washer member,
A working machine configured such that the intersection point between the circular saw blade and a horizontal plane located below the washer member and parallel to the underside of the base is at approximately the same position when the main body is in the non-tilted state as it is when the main body is in the tilted state, and such that the lower end of the washer member moves continuously upward or downward when the main body is tilted from the non-tilted state to the tilted state.