JP2012161899A - Cutting tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance holding feeling so that force mainly for a movement operation can be more efficiently applied to a handle part held by a user in a cutting tool performing cutting by supporting a tool body on an upper surface of a base abutting on a cutting material and moving the tool body in a cutting advancing direction.SOLUTION: A first swelling part K1 and a second recessed part K2 are provided in a first holding part 31 on a rear side in relation to a third swelling part K3 corresponding to a chevron-shaped apex. A fourth swelling part K4, a fifth recessed part K5 and a sixth swelling part K6 are made smoothly continuous on a front side. Each of the swelling parts and the recessed parts is coated with elastomer.

Description

  The present invention relates to a cutting tool called, for example, a portable saw (Circular Saw), in which a user moves in a cutting direction while rotating a circular cutting blade to perform a cutting process.

This type of cutting tool supports a tool body having a circular cutting blade that rotates using an electric motor as a driving source on the upper surface of a base that comes into contact with the upper surface of a cutting material. It protrudes to the lower surface side, and this protruding portion is cut into a cutting material to be cut.
The tool body is provided with a handle that is gripped by the user. The user can perform cutting by holding the handle portion and moving the cutting tool in the cutting progress direction. Various techniques have been provided for the handle portion. In the following Patent Document 1, a sub handle that is gripped by the other hand is provided at the front portion of the handle portion, and an elastomer (a polymer having a rubber-like elastic force (polymer)) is included on the surface of the handle portion including the sub handle. ) To improve the gripability (mainly fit when gripped) of the handle portion.

JP2007-15287

However, with respect to the handle portion described above, it is necessary to further improve the operability when the cutting tool is moved and operated with both hands, for example.
It is an object of the present invention to further improve the handleability of the handle portion and to improve the operability when moving (the ability to easily apply a force for moving operation to the handle).

The above problems are solved by the following invention.
A first invention is a cutting tool that performs a cutting process by moving a tool body in a cutting progress direction with respect to a cutting material, the first gripping part that a user grips with one hand and the other on the tool body A handle portion having a second gripping portion to be gripped by the hand, and the handle portion is a side surface in which the second gripping portion is connected to the front portion of the first grip via a third bulge portion that protrudes upward. The first gripping portion has a second concave portion that protrudes downward in a side view on the back side of the third bulge portion, and a side view on the rear side of the second concave portion. And the second gripping portion has a fourth bulging portion that protrudes upward in a side view on the front side of the third bulging portion, and a side surface on the front side of the fourth bulging portion. A fifth dent that is convex downward in view, and a sixth bulge that is convex upward in side view on the front side of the fifth dent, A range including said a bulge second recess bulge the third, a cutting tool coated with elastomer along a range including the fourth bulge portion and said sixth bulge portion and the fifth recess.
According to the first invention, for example, the first gripping part can be gripped with the right hand, the second gripping part can be gripped with the left hand, and the cutting tool can be pressed against the cutting material and pushed in the cutting progress direction. In this case, the first bulge portion is pressed against the palm of the right hand, and the crotch portion between the thumb and index finger of the right hand is fitted into the second dent portion, so that the right hand moves forward (slips with respect to the handle portion). By being regulated by the third bulge portion, the force for pushing the cutting tool forward in the cutting progress direction can be efficiently transmitted to the handle portion. In addition, the sixth bulge is pressed against the palm of the left hand so that the vicinity of the base of the thumb is fitted into the fifth dent and the rearward movement of the left hand (slip with respect to the handle) is restricted by the fourth bulge. A force for suppressing the movement of the cutting tool toward the front side in the cutting progress direction can be efficiently applied to the handle portion.
Thus, when the first gripping part on the rear side with respect to the third bulge part is gripped with one hand and the second gripping part on the front side is gripped with the other hand, the part that comes into contact with the hand Since all the elastomer is covered, it is possible to obtain a high fit between both hands and to efficiently apply a force to move the cutting tool to the front side in the cutting direction and a force to suppress it. As a result, efficient cutting can be performed.
A second invention is a cutting tool according to the first invention, wherein the elastomer is seamlessly coated along a range including all of the first, third, fourth, and sixth bulge portions and the second and fifth dent portions. is there.
According to the second aspect of the invention, the elastomer is covered seamlessly with respect to the entire handle portion including the first gripping portion and the second gripping portion, so that the elastomer covering portion is always applied regardless of the position or size of the gripped hand. Since it hits the hand, it is possible to have a better fit.
According to a third invention, in the first or second invention, a switch lever that is pulled by an index finger of a hand that grips the first gripping portion is provided, and a second recess is formed on the upper side in the pulling operation direction of the switch lever. It is the arranged cutting tool.
According to the third invention, when the switch lever is pulled by the hand holding the first holding part, for example, with the index finger, the crotch part between the thumb and the index finger is held in a state where it is in contact with the second recessed part. Thus, since the pulling direction (bending direction) of the index finger matches the pulling operation direction of the switch lever, the switch lever can be easily pulled by a natural bending operation of the index finger. In addition, since the circumferential length (thickness) of the handle portion is shortened in the second dent portion, the index lever can be easily bent and the switch lever can be pulled by this point.
A fourth invention is a cutting tool according to any one of the first to third inventions, wherein a finger contact portion is provided for contacting the thumb of the gripped hand to the side portion of the second recess portion.
According to the fourth invention, when the first gripping part is gripped by placing the crotch part between the thumb and the index finger against the second dent part, the thumb can be pressed against the finger resting part, The first gripping portion can be gripped more reliably and the gripability can be improved.
According to a fifth invention, in any one of the first to fourth inventions, the tool body includes a rotating circular cutting blade, and can be tilted up and down on the upper surface side of the base to be brought into contact with the upper surface of the cutting material. The cutting depth of the cutting blade with respect to the cutting material can be adjusted by changing the projecting dimension of the cutting blade to the lower surface side of the base, and the cutting depth of the cutting blade can be adjusted by positioning the tool body at the lower moving end. In the state where the height is maximized, the cutting tool has an inclination angle of 20 ° to 30 ° with respect to the base of the first gripping portion.
According to the fifth aspect of the present invention, in the state where the most frequently used cutting depth is maximum, the force of pushing the cutting tool forward with respect to the first gripping portion with respect to the first gripping portion with one hand gripping the first gripping portion and the A force for pressing the cutting tool against the cutting material can be efficiently applied to the first gripping portion, and the operability of the cutting tool can be enhanced in this respect.

1 is an overall front view of a cutting tool according to an embodiment of the present invention. It is (II) arrow line view of FIG. 1, Comprising: It is the whole top view of a cutting tool. It is (III) arrow directional view of FIG. 1, Comprising: It is the whole cutting tool side view. It is (IV) arrow directional view of FIG. 3, Comprising: It is the whole rear view of a cutting tool. It is the (V)-(V) sectional view taken on the line of FIG. 1, Comprising: It is a longitudinal cross-sectional view of a cutting tool. It is an enlarged view of the internal structure of an electric motor and a reduction gear part. In this figure, a longitudinal sectional view along the axis of the intermediate shaft is shown. It is a rear view of the operation lever of a cutting depth adjustment mechanism, and its periphery. In this figure, the operating lever at the fixed position is indicated by a two-dot chain line, and the operating lever at the loosened position is indicated by a solid line. Moreover, in this figure, the operation member is shown by the structure integrally provided in the base part of the operation lever. It is a perspective view of a single operation lever. It is a surrounding surface of an operation member, and is a side view of a friction part. It is a side view of the friction part of another form. This figure has shown the friction part of the lattice pattern. It is a side view of the friction part of another form. This figure has shown the friction part of a wave pattern. It is a side view of the friction part of another form. This figure has shown the friction part which provided many convex parts. It is a side view of a handle part. It is the schematic diagram which looked at the positional relationship of the motor output shaft of a reduction gear part, an intermediate shaft, and a spindle from the front side.

Next, an embodiment of the present invention will be described with reference to FIGS. As shown in FIG. 1, as an example of the cutting tool 1, a cutting tool called a so-called portable saw (Circular Saw) is illustrated. The cutting tool 1 includes a base 2 that is brought into contact with the upper surface of the cutting material W, and a tool body 10 that is supported on the upper surface of the base 2. The tool main body 10 is supported on the upper surface of the base 2 in a state in which it can be tilted up and down via a main body tilting support shaft 11 on the front side in the cutting progress direction indicated by a white arrow in the drawing. In FIG. 1, the user is located on the left side (rear side) of the cutting tool 1. In the following description, in the front-rear direction of the members and the like, the direction in which cutting proceeds is the front side, and the opposite side is the rear side. The left and right direction is used with reference to the user. Note that the right side of the cutting direction is also referred to as the front side, and the left side is also referred to as the back side.
As shown in FIGS. 1 to 4, the tool body 10 includes a circular cutting blade 13 that is rotated by an electric motor 12. The periphery of the upper half of the cutting blade 13 is covered with a blade case 14. The lower side of the cutting blade 13 protrudes to the lower surface side of the base 2. This protruding portion is covered with a movable cover 15 that can be opened and closed. The movable cover 15 is opened in the clockwise direction in FIG. 1 and the cutting blade 13 is exposed by moving the cutting tool 1 in the cutting progress direction by bringing the front end of the movable cover 15 into contact with the cutting material W. Then, the exposed portion is cut into the cutting material W to be cut.
As shown in FIGS. 2 and 3, the electric motor 12 is attached to the back side of the blade case 14 via a reduction gear portion 20. A handle portion 30 that is gripped by the user is provided in the vicinity of the coupling portion between the reduction gear portion 20 and the electric motor 12. The handle portion 30 has a loop shape extending from the upper surface to the rear surface of the reduction gear portion 20. The handle part 30 includes a first grip part 31 on the rear side that the user grips with one hand, a second grip part 32 on the front side that the user grips with the other hand, and a reduction gear part for the rear part of the first grip part. 20 includes a coupling portion 33 for supporting the rear surface of the battery 20 and a battery mounting base portion 34 provided between the rear portion of the first gripping portion 31 and the rear portion of the coupling portion 33. As shown in FIG. 4, a trigger-type switch lever 35 is provided on the inner peripheral side of the handle portion so that the user can perform a pulling operation with the fingertip (mainly the index finger) of the hand holding the first holding portion 31. . A battery pack 40 as a power source is mounted on the battery mounting base 34 at the rear of the handle 30. The battery pack 40 includes a plurality of cells in a battery case. The battery pack 40 can be repeatedly used as a power source by being removed from the battery mounting base 34 and charged by a separately prepared charger. In the present embodiment, the battery pack 40 can be attached and detached by sliding up and down with respect to the battery attachment base 34.
Details of the handle portion 30 will be described later.

As described above, the tool body 10 is supported at the front portion thereof so as to be tiltable up and down via the body tilting support shaft 11. By changing the vertical tilt position of the tool body 10 with respect to the base 2, the projecting dimension of the cutting blade 13 toward the lower surface of the base can be changed, and thereby the cutting depth with respect to the cutting material W can be adjusted.
As shown in FIGS. 2 and 4, a guide member 3 called a depth guide is attached to the rear portion of the upper surface of the base 2. As shown in FIG. 2, the guide member 3 is provided so as to stand along the back side of the blade case 14 between the blade case 14 and the handle portion 30 when viewed in plan. The guide member 3 is curved in an arc shape along an arc centered on the main body tilting support shaft 11. The guide member 3 is formed with a long arc-shaped guide hole 3a over the almost entire length thereof. A fixing screw 4 is inserted through the guide hole 3a. The fixing screw 4 is fastened to the back surface of the blade case 14. As shown in FIG. 2, the fixing screw 4 extends from the back surface of the blade case 14 to the left (upward in FIG. 2) through the guide hole 3 a of the guide member 3. An operation lever 5 is attached to the left end portion of the fixing screw 4 that extends to the left as viewed from the user. The user can rotate the fixing screw 4 in a tightening direction or a loosening direction by rotating the operation lever 5 by picking the operation lever 5 with a fingertip or the like. When the fixing screw 4 is loosened by operating the operation lever 5, the tool body 10 can be tilted up and down with respect to the base 2. While the fixing screw 4 is loosened, the tool body 10 is tilted up and down with respect to the base 2, thereby adjusting the cutting depth by changing the protruding dimension of the cutting blade 13 to the lower surface side of the base 2. When the operating screw 5 is operated in the tightening direction and the fixing screw 4 is tightened while being tilted to the cutting depth, the vertical tilting position of the tool body 10 is fixed and the cutting depth is fixed to a target dimension. . The cut depth adjusting function is a conventionally known technique, and no particular change is required in the present embodiment.

The cut depth adjusting mechanism according to the present embodiment is characterized by the operation lever 5. The operation lever 5 of this embodiment is shown alone in FIG. The operation lever 5 has an annular base end portion 5a into which the left end portion of the fixing screw 4 is inserted on the inner peripheral side, and a lever portion 5b extending radially from the base end portion 5a. A sawtooth serration is formed in the inner peripheral hole 5c of the annular base end portion 5a, so that the operation lever 5 is integrated with the fixing screw 4 for rotation.
On the peripheral surface of the base end portion 5a, a friction portion M1 against the user's fingertip is provided. In the present embodiment, a plurality of protrusions 5d to 5d that are trapezoidal in cross section and extend in the axial direction are provided on the peripheral surface of the base end portion 5a in the circumferential direction in a parallel state (vertical stripe pattern) to form the friction portion M1. The anti-slip action of the large number of protrusions 5d to 5d functions as the friction part M1 against the fingertip. The user can rotate the operation lever 5 by gripping the lever portion 5b with the fingertip, and press the fingertip against the peripheral surface of the base end portion 5a to apply the force in the rotation direction. It can be rotated, and the fixing screw 4 can be rotated in the tightening direction or the loosening direction. Therefore, in the present embodiment, the base end portion 5 a functions as the rotation operation member S, and the rotation operation member S is provided integrally with the operation lever 5. Note that anti-slip ridges 5e to 5e are also provided at the tip of the lever portion 5b.
According to the friction part M1 (the protrusions 5d to 5d) of the rotary operation member S provided integrally with the operation lever 5, it is possible to improve the operability when adjusting the cutting depth. In FIG. 7, the operation lever 5 that is turned to the tightening position is indicated by a two-dot chain line, and the operation lever 5 that is turned to the loosened position is indicated by a solid line. When the operation lever 5 is turned to the tightening position, the fixing screw 4 is tightened, and the tilting position of the tool body 10 (the cutting depth of the cutting blade 13) is fixed. When the operation lever 5 is turned to the loosened position, the fixing screw 4 is loosened and the tool body 10 can be tilted up and down.

When the operation lever 5 is rotated from the tightening position indicated by the two-dot chain line in FIG. 7 to the loose position indicated by the solid line, the operation lever 5 can be rotated by picking the tip of the lever portion 5b of the operation lever 5 with a fingertip. . By rotating the operating lever 5 to the loosened position, the vertical tilting position of the tool body 10 can be changed to adjust the cutting depth of the cutting blade 13.
When the user presses the base 2 with one hand H (for example, the left hand) and tilts the tool body 10 up and down with the other hand (for example, the right hand), and the cutting depth of the cutting blade 13 reaches the target dimension. Therefore, the cutting depth of the cutting blade 13 can be fixed by rotating the operation lever 5 to the tightening position indicated by the two-dot chain line in FIG. At this time, the user presses the base 2 with one hand H and holds the tool body 10 in the vertical tilt position with the other hand, so that the fingertip reaches the tip of the lever portion 5 b of the operation lever 5. There may not be. Even in this case, as shown in FIG. 7, for example, the index finger Hf of the left hand H holding the base 2 is extended and pressed against the peripheral surface (friction part M1) of the proximal end portion 5a closer to the operation lever 5. By moving the fingertip in the circumferential direction, the operating lever 5 can be rotated in the tightening direction, whereby the tip of the lever portion 5b of the operating lever 5 can be moved to a position on the near side where the fingertip reaches, or The vertical tilt position of the tool body 10 can be temporarily fixed.
For this reason, while holding the positions of the base 2 and the tool body 10, the friction part M1 is moved with the fingertip to move the operation lever 5 forward, and then the lever part 5b is picked and rotated to the tightening position to fix the fixing screw 4 Can be tightened firmly, or after the above-described temporary fixing, the fixing screw 4 can be firmly tightened by rotating the lever 5b of the operating lever 5 downward while releasing the hand from the base 2 or the tool body 10. Can be tightened.
Thus, in the operation of adjusting the cutting depth of the cutting blade 13, the base 2 is pressed with one hand H, and the operation lever 5 is securely held while the vertical tilt position of the tool body 10 is held with the other hand. Further, since it can be easily rotated in the tightening direction, it is possible to reliably fix the target depth of cut once set without being displaced.

In the present embodiment, the configuration in which the base end portion 5a of the operation lever 5 functions as the rotation operation member S is illustrated as described above. However, a cylindrical rotation operation member S2 may be disposed separately from the operation lever 5. . The rotation operation member S2 prepared separately from the operation lever 5 is attached to the fixing screw 4 between, for example, the blade case 14 and the handle portion 30 (upper side of the guide member 3 in FIG. 2) in plan view. can do. The operation lever 5 may be omitted and the fixing screw 4 may be tightened and loosened only by the rotation operation member. 9 to 12 show a rotation operation member S provided separately from the operation lever 5.
Further, the rotation operation member S has a cylindrical shape with a circular cross section as illustrated, a truncated cone shape, a cylindrical shape with an elliptical cross section, a cylindrical shape with an elliptical cross section, a triangular shape (a rice ball shape), or a rectangular shape. Or it is good also as a structure which provides the friction part M1 in the surrounding surface of the member which has a polygonal cylindrical shape, or the member which makes | forms a spherical body.
Furthermore, although the structure which provided the protrusion 5d-5d of trapezoidal cross section in a vertical stripe pattern as the friction part M1 was illustrated, as a friction part of the rotation operation member S, it can change into another form. For example, a frictional part M2 in which ridges or grooves having a cross-sectional mountain shape, V-shape or semicircular shape are arranged in a lattice pattern as shown in FIG. 9, and a frictional part M3 in a wave pattern as shown in FIGS. , M4, or a plurality of protrusions (bottom points) on the peripheral surface as shown in FIG. Moreover, a wrinkle pattern and a shark skin (skin skin, rough surface) may be used as the friction part, or vinyl may be attached to the peripheral surface as the friction part. Further, the characteristics of the material itself may be used as the friction part by molding the rotary operation part using rubber or silicon as a material. Thus, by providing the fixing screw 4 with a substantially cylindrical (columnar shape) rotation operation member having sufficient frictional resistance with respect to at least the fingertip, it is possible to perform rotation operation mainly in the tightening direction with one finger. As a result, it is possible to achieve convenience when adjusting the cutting depth.

Next, the cutting tool 1 according to the present embodiment is characterized by the handle portion 30. Details of the handle portion 30 are shown in FIG. The handle portion 30 has a loop shape in which a first grip portion 31 on the rear side and a second grip portion 32 on the front side are connected in a mountain shape. A battery mounting base 34 is provided at the rear of the first grip 31. A coupling portion 33 is provided at the rear portion of the first grip portion 31 via the battery mounting base portion 34. The front portion of the coupling portion 33 is coupled to the rear surface of the reduction gear portion 20. The front portion of the second grip portion 32 is coupled to the front side of the reduction gear portion 20.
The upper surface of the handle portion 30 mainly has a bulge (bumpy) shape with a slight bulge or dent in accordance with the undulation (bulge) of the hand to be gripped. A connecting portion between the first gripping portion 31 and the second gripping portion 32 that is the apex of the mountain shape of the handle portion 30 is provided with a third convex portion K3 having a convex shape that is smooth upward in a side view. The first grip portion 31 extends from the third bulge portion K3 so as to fall obliquely downward rearward. The inclination angle θ of the first grip portion 31 with respect to the base 2 that is inclined obliquely downward is set to about 20 ° in a state where the cutting depth is maximized. The inclination angle θ of the first grip portion 31 with respect to the base 2 is desirably set in the range of 20 ° to 30 °. By giving the inclination angle θ larger than usual in this range, when the cutting tool 1 is moved in the cutting progress direction with the maximum cutting depth that is frequently used, the operation force pushed by the user is most effectively increased. 1 can be added to the gripping portion 31, whereby the operability and workability of the cutting tool 1 can be further enhanced.
In the first grip portion 31, a second concave portion K2 having a smooth convex shape downward in a side view is provided behind the third bulge portion K3. On the rear side of the second dent K2, a first bulge K1 having a convex shape that is smooth upward in a side view is provided. In the second grip 32, a fourth bulge K4 having a convex shape that is smooth upward in a side view is provided on the front side of the third bulge K3. On the front side of the fourth bulge portion K4, a fifth concave portion K5 having a smooth convex shape downward in a side view is provided. On the front side of the fifth recess K5, a sixth bulge K6 having a convex shape that is smooth upward in a side view is provided. The second grip 32 is provided with a front grip 36 protruding forward. The upper surface of the front grip portion 36 is a sixth bulge portion K6, and the upper surface of the base portion is a fifth recess portion K5. From the front side of the handle portion 30, the sixth bulge portion K6, the fifth dent portion K5, the fourth bulge portion K4, the third bulge portion K3, the second dent portion K2, and the first bulge portion K1 are each continuous and smooth. It is connected with a straight line
Further, the upper surface of the handle portion 30 from the front side of the handle portion to the sixth bulge portion K6, the fifth dent portion K5, the fourth bulge portion K4, the third bulge portion K3, the second dent portion K2, and the first bulge portion K1. All of them are covered with an elastomer to prevent slipping, and have good gripping properties (fitting to the palm and fingertips). In particular, in the present embodiment, the entire surface except the left and right side portions of the front grip portion 36 is covered with an elastomer.
Furthermore, the lower surface side and the left and right side surfaces of the first grip portion 31 are also covered with an elastomer. The elastomer is also covered in the upper half range of the battery mounting base 34. In this way, when the handle portion 30 is gripped with one or both hands, the elastomer is covered over almost the entire range where the user's hand hits, the handle portion 30 is prevented from slipping, and has a good gripping property. Has been. In FIG. 13, the area covered with the elastomer is shaded.
In the present embodiment, the upper surface, the lower surface, and the left and right side surfaces of the handle portion 30 and the elastomer that covers the upper surface and the left and right side surfaces of the battery mounting base portion 34 are connected to each other at the rear portion of the first grip portion 31. Thus, the moldability of the handle portion 30 in the elastomer coating process is enhanced.

The handle portion 30 has improved gripping performance in both cases where the user performs a moving operation with one hand and a moving operation with both hands. For example, when gripping the first grip portion 31 with the right hand and gripping the second grip portion with the left hand, the base portion (crotch portion) between the thumb and forefinger of the right hand is fitted into the second recess K2. The first bulge portion K1 is pressed against the palm of the hand and can be gripped. By grasping in this way, the third bulging portion K3 having a convex shape is positioned on the front side of the crotch portion between the thumb and the index finger of the right hand. Therefore, when the cutting tool 1 is pushed forward in the cutting progress direction In addition, the right hand force can be efficiently applied to the cutting tool 1 through the handle portion 30, thereby improving the operability of the cutting tool 1.
Further, a switch lever 35 is disposed obliquely forward and downward of the second concave portion K2 that is convex downward in a side view. Thus, the second recess K2 is located on the operation line in the pulling operation direction (backward and upward) of the switch lever 35. For this reason, for example, when the first grip portion 31 is gripped with the crotch portion between the thumb and index finger of the right hand fitted in the second recess K2, the bending direction of the index finger matches the moving direction of the switch lever 35. Therefore, pull the index finger on the switch lever 35 to perform its pulling operation (ON operation), and reversely perform the return operation (OFF operation) by twisting the index finger, etc. The switch lever 35 can be operated, thereby reducing the burden on the index finger and improving the operability of the switch lever 35.
Furthermore, a finger rest 37 that is an oval depression is provided between the second recess K2 and the switch lever 35 on the operation direction line of the switch lever 35. The finger contact portion 37 is provided in an elastomer (elastomer covering region) covered on the lower surface side of the first grip portion 31. By pressing the thumb of the hand gripping the first gripping portion 31 against the finger contact portion 37, the slip is more reliably prevented, thereby improving the gripping performance of the first gripping portion 31 and thus the handle portion 30. it can. The finger rests 37 are provided on both the left and right sides of the first grip 31. The right finger pad 37 shown in FIG. 13 is pressed against the thumb when the first grip 31 is gripped with the left hand.
In addition, as described above, the fourth bulge portion K4 is provided between the third bulge portion K3 and the fifth dent portion K5 and at a portion closer to the fifth bulge portion K5 than the third bulge portion K3. . When the front grip portion 36 of the second grip portion 32 is gripped by, for example, the left hand and the vicinity of the base of the thumb is fitted into the fifth recess portion K5, the cutting direction with respect to the handle portion 30 is cut by the fourth bulge portion K4. It becomes easier to apply backward force.

Next, the cutting tool 1 according to the present embodiment is characterized by a reduction gear unit 20 that decelerates the rotational output of the electric motor 12 in two stages and outputs it to the spindle 29. 5 and 6 show details of the reduction gear unit 20. The gear case 21 of the reduction gear unit 20 is integrally provided on the back side of the blade case 14. A motor case 12 b of the electric motor 12 is coupled to the back side of the gear case 21. The output shaft 12 a of the electric motor 12 enters the gear case 21. The drive gear portion provided on the output shaft 12 a is meshed with the intermediate drive gear 22. The intermediate drive gear 22 is fixed on the intermediate shaft 23. The intermediate shaft 23 is rotatably supported by the gear case 21 via bearings 23a and 23b between the output shaft 12a of the electric motor 12 and the spindle 29. On the intermediate shaft 23, the intermediate drive gear 22 and the intermediate driven gear 24 are fixed. The intermediate driven gear 24 is meshed with an output gear 26 fixed to the spindle 29. The rotational output of the electric motor 12 is decelerated and output to the spindle 29 in two stages: meshing between the drive gear portion and the intermediate drive gear 22 and meshing between the intermediate driven gear 24 and the output gear 26. The spindle 29 is rotatably supported by the gear case 21 via bearings 25 and 27. The tip end side (left end side in FIG. 5) of the spindle 29 protrudes into the blade case 14, and a circular cutting blade 13 is attached to the protruding portion.
The output shaft 12a, the intermediate shaft 23, and the spindle 29 of the electric motor 12 are not on the same plane, and the intermediate shaft 23 is on the front side with respect to a reference line J connecting the axis C1 of the output shaft 12a and the axis C3 of the spindle 29. It is arranged at a position shifted from the center. This positional relationship is shown in FIGS. As shown in the drawing, the axis C2 of the intermediate shaft 23 is disposed so as to be displaced by a dimension D to the front in the cutting progress direction with respect to a reference line J connecting the axis C1 of the output shaft 12a and the axis C3 of the spindle 29. . For this reason, the reduction gear unit 20 is configured to be compact in the height direction as compared with a configuration in which the intermediate shaft 23 is disposed on the reference line J. Further, since the speed is reduced in two stages via the intermediate shaft 23, the gear diameter of the output gear 26 can be made smaller than that in the single speed reduction, and thus the tool body 1 can be moved relative to the base 2. A greater depth of cut can be set by closer approach.
In addition, since the intermediate shaft 23, the drive-side intermediate gear 22, and the driven-side intermediate gear 24 are displaced to the front side with respect to the reference line J, the reduction gear unit 20 and thus the cutting are compared with the configuration to be displaced to the rear side. The center of gravity of the tool 1 can be displaced forward. For this reason, in the configuration in which the battery pack 40 having a relatively large weight is attached to the rear portion of the handle portion 30, the center of gravity of the cutting tool 1 can be displaced to the front as much as possible, and the weight balance thereof can be achieved. Or workability can be improved.

In this embodiment, in addition to the intermediate shaft 23 and the like by two-stage deceleration, the front grip portion 36, the illumination device 41, the blower outlet 42, the spindle lock lever 43, the wrench holding portion 44, and the like are also weight balanced with the battery pack 40. Are arranged in front of the reference line J. As shown in FIG. 1, the front grip portion 36 of the second grip portion 32 is disposed in front of the reference line J. Further, on the back side of the blade case 14, an illumination measure 41 is provided to illuminate mainly the cutting site (the cut portion of the cutting blade 13 with respect to the cutting material W). An LED as a light source constituting the illumination device 41, a substrate on which the LED is mounted, and the like are arranged in front of the reference line J.
On the back side of the blade case 14, a blower device is provided for blowing the cooling air of the electric motor 12 toward the smear line alignment guide 2 a provided on the entire surface of the base 2. It is arranged in front of the line J. As shown in FIGS. 5 and 6, a cooling air fan 12 c is attached to the output shaft 12 a of the electric motor 12. When the cooling fan 12c rotates integrally with the output shaft 12a, outside air is introduced from the rear portion of the motor case 12b, and the electric motor 12 is cooled. The cooling air is introduced into the motor case 12b and blown out from the blow-out port 42 of the blower device toward the smear line guide 2a. The cutting powder in the vicinity of the sumi guide 2a is blown off by the wind blown from the blow-out port 42, and the visibility is ensured.
As shown in FIG. 4, a spindle lock lever 43 is disposed at the front portion of the electric motor 12. When the spindle lock lever 43 is operated to move in the pushing direction with respect to the motor case 12b, the spindle lock lever 43 is engaged with the two-surface width portion formed on the output shaft 12a of the electric motor 12, and its rotation is locked. Thereby, the rotation of the spindle 29 is locked, and the convenience at the time of replacement of the cutting blade 13 is achieved. The spindle lock lever 43 is also arranged on the front side with respect to the reference line J.
As shown in FIGS. 3 and 4, a wrench holding portion 44 is integrally provided at the front portion of the electric motor 12. For example, a hexagon wrench 45 can be inserted and held in the wrench holding portion 44. The hexagon wrench 45 is used, for example, for tightening and loosening a fixing screw for fixing the cutting blade 13 to the spindle 29 in the replacement operation of the cutting blade 13. Since the hexagon wrench 45 can be held along the front portion of the electric motor 12, it is not necessary to bother to search for the necessary hexagon wrench for exchanging the cutting blade. Can be done quickly. Since the hexagon wrench 45 is held in front of the electric motor 12 and in front of the reference line J, a weight balance with respect to the battery pack 40 can be achieved.
As described above, in the rechargeable cutting tool 1 according to this embodiment, the center of gravity of the reduction gear unit 20 is displaced to the front side in order to balance the weight with the battery pack 40 having a relatively large weight. Is devised to be displaced more forward than the reference line J. By taking a weight balance with respect to the battery pack 40, it is possible to improve the handleability and operability such as reducing the fatigue of the user's hand for supporting the cutting tool 1 during the cutting operation.

According to the cutting tool 1 of the present embodiment configured as described above, the first bulge portion K1 and the first bulge portion K1 are connected to the first grip portion 31 on the rear side of the handle portion 30 having a mountain shape with the third bulge portion K3 as a vertex. A second dent K2 is provided, and a fourth bulge K4, a fifth dent K5, and a sixth bulge K6 are provided in the second grip 32 on the front side. For this reason, for example, the first grip portion 31 is gripped with the right hand, the front grip portion 36 of the second grip portion 32 is gripped with the left hand, and the cutting tool 1 is pressed against the cutting material W and pushed in the cutting progress direction to perform cutting processing. When performing, the first bulge portion K1 is pressed against the palm of the right hand, and the crotch portion between the thumb of the right hand and the index finger is fitted into the second recess portion K2 to move forward of the right hand (handle portion 30 By regulating the third bulge portion K3, the force for pushing the cutting tool 1 forward in the cutting progress direction can be efficiently transmitted to the handle portion 30. Further, the sixth bulge portion K6 is pressed against the palm of the left hand, and the vicinity of the base of the thumb is fitted into the fifth dent portion K5 so that the rearward movement of the left hand (sliding with respect to the handle portion 30) is performed by the fourth bulge portion K4. By regulating, a force for suppressing the movement of the cutting tool 1 toward the front side in the cutting progress direction can be efficiently applied to the handle portion 30.
Thus, since the bulge part and the dent part are finely set in the handle part 30 according to the unevenness of the user's hand, the handle part 30 can be given high gripping properties and the cutting tool 1 can be A force for moving to the front side in the cutting progress direction and a force for suppressing the force can be efficiently applied to the handle portion 30, whereby an efficient cutting process can be performed. In addition, since the elastomer is seamlessly covered over almost the entire front-rear direction of the handle portion 30, a high-fitting feeling (good gripping properties) of both hands can be obtained.
Further, according to the handle portion 30 according to the present embodiment, since the second recessed portion K2 is disposed on the upper side in the pulling operation direction of the switch lever 35, the switch with the index finger of the hand holding the first holding portion 31 is used. When pulling the lever 35, the pulling direction (bending direction) of the index finger is changed to the pulling operation direction of the switch lever 35 by gripping the crotch portion between the thumb and the index finger in contact with the second recess K 2. Since they match, the switch lever 35 can be easily pulled by the natural bending operation of the index finger. In addition, since the circumferential length (thickness) of the handle portion 30 is shortened in the second recess K2, the switch lever 35 can be operated by pulling the index finger easily.
Furthermore, according to the handle part 30 according to the present embodiment, the finger rest part 37 for bringing the thumb of the hand holding the first holding part 31 into contact with the side part of the second recessed part K2 is provided. . Since the first gripping portion 31 can be gripped by pressing the thumb against the finger rest portion 37, the gripping performance can be improved by gripping the first gripping portion 31 more reliably.
Further, according to the handle portion 30 of the present embodiment, the inclination angle of the first gripping portion 31 with respect to the base 2 is set to about 20 ° with the cutting depth of the cutting blade 12 being maximized. The tilt angle is tight. According to the first gripping portion 31, in the state where the most frequently used cutting depth is maximum, the force that pushes the cutting tool 1 forward with the one hand gripping the first gripping portion 31 and the cutting tool 1. Can be efficiently applied to the first gripping portion 31, and the operability of the cutting tool 1 can be improved in this respect.
Various modifications can be made to the embodiment described above. For example, the case where the inclination angle θ of the first grip portion 31 with respect to the base 2 is set to about 20 ° with the cutting depth set to the maximum is illustrated, but the inclination angle θ is in the range of 20 ° to 30 °. The angle of inclination can be set more tightly.

W ... Cutting material 1 ... Cutting tool
2 ... Base, 2a ... Sumi wire guide 3 ... Guide member (depth guide), 3a ... Guide hole 4 ... Fixing screw 5 ... Operation lever M1 ... Friction part S ... Rotation operation member H ... Left hand, Hf ... Index finger 5a ... Base end Part, 5b ... lever part, 5c ... inner peripheral hole, 5d ... ridge (friction part)
5e ... ridge (lever part)
DESCRIPTION OF SYMBOLS 10 ... Tool body 11 ... Main body tilting support shaft 12 ... Electric motor 13 ... Cutting blade 14 ... Blade case 15 ... Movable cover 20 ... Reduction gear part J ... Reference line which connects the shaft center C1 of a motor output shaft, and the shaft center C3 of a spindle C1 ... shaft center of motor output shaft, C2 ... shaft center of intermediate shaft, C3 ... shaft center of spindle 21 ... gear case 22 ... intermediate drive gear 23 ... intermediate shaft, 23a, 23b ... bearing 24 ... intermediate driven gear 25 ... bearing 26 ... output gear 27 ... bearing 29 ... spindle 30 ... handle part 31 ... first gripping part θ ... inclination angle K1 with respect to base of first gripping part K1 ... first bulge part, K2 ... second dent part, K3 ... third bulge part 32 ... 2nd grip part K4 ... 4th bulge part, K5 ... 5th dent part, K6 ... 6th bulge part 33 ... Connection part 34 ... Battery mounting base part 35 ... Switch lever 36 ... Front grip part 4 ... Battery pack 41 ... illuminating device 42 ... blower outlet 43 ... spindle lock lever 44 ... wrench holder 45 ... Allen wrench

Claims (5)

A cutting tool that performs cutting by moving the tool body in the cutting progress direction with respect to the cutting material,
The tool body includes a handle portion having a first grip portion gripped by a user with one hand and a second grip portion gripped by the other hand,
The handle portion has a chevron shape in a side view in which the second grip portion is connected to the front portion of the first grip through a third bulge portion that is convex upward.
The first gripping portion has a second dent that protrudes downward in a side view behind the third bulge, and the first bulge that protrudes upward in a side view behind the second dent. Part
The second gripping portion has a fourth bulge portion that is convex upward in a side view on the front side of the third bulge portion, and a fifth dent portion that is convex downward in a side view on the front side of the fourth bulge portion. And has a sixth bulge portion that is convex upward in a side view on the front side of the fifth dent portion,
A cutting tool coated with an elastomer along a range including the first bulge portion, the second dent portion, and the third bulge portion, and a range including the fourth bulge portion, the fifth dent portion, and the sixth bulge portion. . The cutting tool according to claim 1, wherein the elastomer is seamlessly coated along a range including all of the first, third, fourth, and sixth bulge portions and the second and fifth recess portions. The cutting tool according to claim 1 or 2, further comprising a switch lever that is pulled by an index finger of a hand that grips the first grip portion, and the second recess portion is provided above the switch lever in a pulling operation direction. Placed cutting tool. The cutting tool according to any one of claims 1 to 3, wherein a finger contact portion is provided for abutting a thumb of a gripped hand on a side portion of the second recess portion. It is a cutting tool given in any 1 paragraph of Claims 1-4,
The tool body is provided with a rotating circular cutting blade, and is supported on the upper surface side of the base that is in contact with the upper surface of the cutting material so as to be tiltable up and down, thereby changing the protruding dimension of the cutting blade to the lower surface side of the base The cutting depth of the cutting blade with respect to the cutting material can be adjusted by
A cutting tool in which an inclination angle of the first grip portion with respect to the base is set to 20 ° to 30 ° in a state where the cutting depth of the cutting blade is maximized by positioning the tool main body at the lower moving end.

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