JP7601672B2 - Benchtop cutting machine - Google Patents

Description

The present invention relates to a bench cutter used for cutting materials such as wood.

For example, this type of bench cutter has a base that is placed on a table or floor, a turntable on which the material to be cut is placed, and a cutting machine body equipped with a cutting tool that is provided above the turntable. The turntable is supported on the base so that it can rotate horizontally. The cutting machine body is supported on the turntable so that it can swing up and down. The cutting tool is rotated using an electric motor as a drive source, and the cutting machine body is swung downward toward the turntable. This allows the cutting tool to cut into the material to be cut that is placed on the top plate of the turntable.

When the cutting machine body is swung downward, the support arm that supports the cutting machine body is subjected to a force that pulls it upward. The support arm is connected to a connecting part at the rear of the turntable. As a result, the connecting part and the rear part of the turntable, which is integrated with the connecting part, are subjected to stress that causes them to bend and deform upward. For example, the top plate of the turntable is subjected to stress that causes the rear part to bend and deform upward. When the top plate is bent and deformed, the horizontality of the top plate is lost, making it difficult to cut the placed material with precision.

Patent documents 1 and 2 describe a protrusion (rib) that extends downward from the underside of the top plate of the turntable. The rib extends linearly from the rear of the top plate toward the front. By providing the rib on the underside of the top plate, bending deformation of the top plate is suppressed. The rib described in Patent document 1 is configured to also serve as the vertical wall of the cutting edge near the center of the top plate. The cutting edge is recessed downward so that the cutting tool can enter below the upper surface of the top plate when the cutting machine body is swung downward. By having the rib also serve as the vertical wall of the cutting edge, deformation of the cutting edge is suppressed.

JP 2007-331289 A JP 2008-137165 A

In order to make bench cut-off machines lighter than conventional ones, for example, it is possible to provide a lightweight turntable. To make the turntable lighter, a highly rigid structure that suppresses bending deformation more than conventional ones is required. Therefore, there has been a demand for bench cut-off machines in which bending deformation is suppressed by improving the rigidity of the turntable.

According to one feature of the present disclosure, the tabletop cutter has a cutter body that rotatably supports a disk-shaped cutting tool in a position extending in the front-rear direction, and a turntable that supports the cutter body so that it can move in the up-down direction. The turntable is provided with a disk-shaped top plate portion on which the material to be cut is placed, and a connecting portion at the rear of the top plate portion to which the cutter body is connected. A rotating shaft portion that extends downward from the center of the bottom surface of the top plate portion and is rotatably attached to the base, and a vertical wall portion that extends downward from the outer periphery of the top plate portion and has a lower end that slides against the base. At least one protrusion is provided on the bottom surface of the top plate portion, extending forward from the rear front surface of the vertical wall portion. The protrusion has a rear protrusion that extends in the front-rear direction in either the left or right region of the rotating shaft portion. The protrusion has a front protrusion that extends further forward from the front end of the rear protrusion in a direction away from the cutting tool and until it reaches a front region forward of the rotating shaft portion.

Therefore, the rigidity of the turntable can be increased by the ridges provided on the underside of the top plate. The ridges have a rear ridge that protrudes forward from the rear of the turntable, and a front ridge that extends further forward from the front end of the rear ridge and away from the cutting tool. Therefore, the ridges extend along the flow of the stress direction of the bending stress that the turntable receives when the connecting part is pulled upward. Therefore, the ridges can efficiently suppress bending deformation of the turntable. Moreover, the front ridges extend to the front area of the top plate on which the material to be cut is placed. Therefore, the rigidity of the front area of the top plate can be improved. Therefore, the horizontality of the upper surface can be maintained in the front area of the top plate. This allows the material to be cut to be placed in a stable position on the top surface of the top plate.

FIG. 1 is a perspective view of a bench cutter according to a first embodiment. FIG. 2 is a left side view of the bench cutter including a vertical cross-sectional view of the base and the turntable. FIG. 13 is a left side view illustrating a bending deformation of the turntable. FIG. FIG. 6 is a cross-sectional view taken along line VI-VI in FIG. 5, and is a vertical cross-sectional view of the base and the turntable. FIG. 2 is a perspective view of the turntable as viewed from above. 2 is a perspective view of the turntable as viewed from the bottom right side. FIG. FIG. 2 is a perspective view of the turntable as viewed from the bottom side. FIG. FIG. 13 is a bottom view illustrating a flow of bending stress acting on the turntable in a stress direction. FIG. 11 is a bottom view of the turntable according to the second embodiment. FIG. 11 is a bottom view of the turntable according to the third embodiment. FIG. 13 is a bottom view of the turntable according to the fourth embodiment. FIG. 13 is a bottom view of the turntable according to the fifth embodiment. FIG. 13 is a bottom view of the turntable according to the sixth embodiment.

According to another feature of the present disclosure, the front end of the front protrusion is connected to the vertical wall portion. This further improves the rigidity of the front area of the turntable. This increases the stability of the workpiece placed on the top surface of the front area of the top plate.

According to another feature of the present disclosure, the front ridge extends in an arc shape away from the cutting tool. The arc shape of the front ridge is therefore closer to the flow of the bending stress on the turntable. This allows the rigidity of the turntable to be improved without significantly changing the total weight of the ridge.

According to another feature of the present disclosure, the front protrusion intersects with an imaginary plane that passes through the center of the rotating shaft and extends in the left-right direction at an angle of 10° to 80°. Therefore, the front protrusion is provided across the rear region of the turntable behind the imaginary plane and the front region of the turntable ahead of the imaginary plane. The flow of the stress direction has already changed direction to a direction away from the cutting tool behind the imaginary plane. Therefore, by providing the front protrusion along the flow of the stress direction, the rigidity of both the rear region and the front region of the turntable can be improved.

According to another feature of the present disclosure, the rear protrusion extends so as to intersect with the vertical wall portion, and the rear end of the rear protrusion is connected to the connecting portion. Thus, the rear protrusion is connected to the top plate portion, the vertical wall portion, and the connecting portion. Therefore, the rigidity of the top plate portion on which the rear protrusion is provided can be improved by utilizing the rigidity of the vertical wall portion and the connecting portion.

According to another feature of the present disclosure, the connecting portion is tubular and extends in the front-rear direction. The rear protrusion extends along either the left or right side surface of the connecting portion. The rear protrusion is therefore connected to the connecting portion along the left or right side surface of the connecting portion extending in the front-rear direction. This makes it possible to increase the rigidity of the rear protrusion in the front-rear direction. The rear protrusion is connected to the underside of the top plate portion, extending in the front-rear direction. This makes it possible to improve the rigidity of the top plate portion to which the rear protrusion is connected.

According to another feature of the present disclosure, the front protrusion extends from the front end of the rear protrusion and decreases in height in the vertical direction. Therefore, the vertical height of the front protrusion can be changed according to the rigidity required at each position on the turntable. The bending stress that the turntable receives decreases from the rear to the front. Therefore, the weight of the turntable can be reduced while ensuring the rigidity required at each position on the turntable.

According to another feature of the present disclosure, the turntable has a second ridge on the underside of the top plate, which extends rearward from the rear surface of the rotating shaft and away from the cutting tool. The second ridge intersects with the ridge. Thus, the second ridge intersects with the ridge at a relatively large angle. Therefore, by having the ridge and the second ridge work together, it is possible to increase the rigidity of a wide area of the rear region of the turntable.

According to another feature of the present disclosure, the turntable has a third ridge that extends in the front-rear direction in an area closer to the cutting tool than the ridge. The third ridge can therefore further increase the rigidity of the center of the turntable. Moreover, the third ridge can be provided along the flow of the stress direction. This further suppresses bending deformation of the top plate.

The first embodiment of the present disclosure will be described with reference to Figs. 1 to 10. In this embodiment, a bench cutter 1, which is called a sliding circular saw, is illustrated. As shown in Fig. 1, the bench cutter 1 has a base 2 that is placed on a table or floor, a turntable 4 for placing the material to be cut, and a cutter body 10. The turntable 4 is located above the base 2 and supported by the base 2. The cutter body 10 is provided above the turntable 4. A substantially disk-shaped blade 11 called a tipped saw blade is rotatably supported on the cutter body 10. A user performs cutting work by positioning himself in front of the bench cutter 1. In the following description, the direction in which the side of the blade 11 extends is defined as the front-rear direction of the members and configuration, and the front side is defined as the front side as seen from the user. The up-down and left-right directions of the members and configuration are defined based on the blade 11 as seen from the user positioned in front.

As shown in Figures 1 and 4, the turntable 4 has a tabletop portion 50 that is disk-shaped in plan view. The table top surface 50a of the tabletop portion 50 is horizontal. The turntable 4 can rotate horizontally around a table rotation shaft 2a located in the center of the tabletop portion 50. The rotation structure of the turntable 4 on the table rotation shaft 2a will be described in detail later.

As shown in FIG. 1, the base 2 has an auxiliary table 3 on both the left and right sides of the turntable 4. The upper surface of the auxiliary table 3 is set at the same upper surface height as the table upper surface 50a. The turntable 4 has a table extension 5 that extends forward from the front of the top plate 50 along the side of the cutting tool 11. A cutting edge plate 5a extending horizontally is provided on the table upper surface 50a and the upper surface of the table extension 5. A notched groove 5b extending in the front-rear direction along the side of the cutting tool 11 is provided in the center of the cutting edge plate 5a. An adjustment bolt 43 that supports the table extension 5 from below is provided at the bottom of the table extension 5. The adjustment bolt 43 is supported by the table extension 5 and can be moved up and down by screw operation. The adjustment bolt 43 is moved up and down to abut the lower end of the adjustment bolt 43 against the floor surface. This allows the height of the table extension 5 to be adjusted. In addition, it is possible to eliminate any wobbling when installing the table extension 5.

As shown in Figures 1 and 2, above the table top 50 and auxiliary table 3, a wall-shaped positioning fence 6 is provided that extends in the left-right direction and upward. The positioning fence 6 is supported on the upper surfaces of the left and right auxiliary tables 3. The positioning fence 6 has a positioning surface 6a that stands vertically on the front surface. The positioning surface 6a is located on a vertical plane that passes through the table rotation support shaft 2a. The workpiece W placed on the table top surface 50a is positioned in the front-rear direction by being pressed against the positioning surface 6a.

As shown in Figs. 1 and 4, an arc-shaped miter scale plate 7 is provided in a region of approximately half the circumference of the front part of the base 2. The miter scale plate 7 is provided so as to extend horizontally below the table top surface 50a. The miter scale plate 7 has a plurality of groove-shaped positioning recesses 7b extending radially. The positioning recesses 7b are provided at a predetermined angular interval in the circumferential direction of the miter scale plate 7. The tip of a positioning pin 41a (described later) can enter the positioning recesses 7b. The miter scale plate 7 is fixed to the base 2 by a fixing screw 7a. The fixing screw 7a is inserted into a long hole in the base 2. The angle between the positioning fence 6 and the cutting tool 11 can be finely adjusted by loosening the fixing screw 7a and moving the miter scale plate 7 left and right. For example, when the positioning pin 41a is inserted into the positioning recess 7b at a right angle, the angle between the cutting tool 11 and the positioning fence 6 can be precisely adjusted to a right angle. This adjustment is mainly performed during the production process.

1 and 2, a main body support arm 30 extending substantially upward is provided behind the turntable 4. The main body support arm 30 can be tilted left and right around a left and right tilting support shaft 30a extending in the front and rear direction. The arm side connecting part 30b at the lower part of the main body support arm 30 is connected to a cylindrical connecting part 51 provided on the turntable 4 so as to be tiltable left and right. A long slide bar 31 extending parallel to the side of the cutting tool 11 and along a horizontal line is provided on the upper part of the main body support arm 30. Two slide bars 31 are provided in the vertical direction. The slide bar 31 supports a slide base 32 that can slide in the front and rear direction. By sliding the slide base 32 in the front and rear direction, the cutting tool 11 can cut a workpiece W that is placed on the turntable 4 and has a wide width in the front and rear direction. The cutting machine main body 10 can be swung up and down relative to the slide base 32 around a vertical swing support shaft 10a provided on the slide base 32 and extending in the left and right direction.

As shown in FIG. 2, the cutting tool 11 is rotatably attached to the cutting machine body 10 forward of the vertical swing support shaft 10a. The cutting tool 11 is attached integrally to an output shaft (not shown) that extends in the left-right direction. By swinging the cutting machine body 10 downward, the cutting tool 11 can be caused to cut into the workpiece W placed on the top plate 50 and table extension 5.

As shown in Figs. 1 and 2, the cutting machine body 10 has a fixed cover 12 and a movable cover 13 that cover the periphery of the cutting tool 11. The fixed cover 12 covers the upper half of the cutting tool 11. A white arrow 12a indicating the rotation direction of the cutting tool 11 is displayed on the left side of the fixed cover 12. The movable cover 13 can cover the lower half of the cutting tool 11. The movable cover 13 rotates in conjunction with the up and down swing of the cutting machine body 10 to open and close the lower half of the cutting tool 11. When the cutting machine body 10 is swung upward, the movable cover 13 rotates in the closing direction (clockwise direction in Fig. 2). This covers the lower half of the cutting tool 11. When the cutting machine body 10 is swung downward, the movable cover 13 rotates in the opening direction (counterclockwise direction in Fig. 2). This exposes the lower half of the cutting tool 11.

As shown in Figures 1 and 4, the cutting machine body 10 has a motor housing 14 to the right of the fixed cover 12 and the movable cover 13 and to the left of the slide bar 31. The motor housing 14 houses an electric motor 15. As an example of the electric motor 15, a motor called a DC brushless motor is used. The output of the electric motor 15 is transmitted to the output shaft while being reduced in speed via a reduction gear train located between the electric motor 15 and the cutting tool 11.

As shown in Figures 1 and 4, a rectangular box-shaped controller housing 16 is provided behind the motor housing 14. The controller housing 16 houses the controller 17. The controller 17 has a shallow, roughly rectangular case and a control board housed within the case and molded with resin. The controller 17 is equipped with a control circuit, a drive circuit, an auto-stop circuit, etc., which are mainly used to control the operation of the electric motor 15.

As shown in Figures 1 and 2, a battery mounting section 18 is provided at the rear of the controller housing 16. The mounting surface of the battery mounting section 18 faces rearward when the cutting machine body 10 is at the top dead center and extends vertically. The battery mounting section 18 can be attached and detached by sliding a battery pack 19, which is in the shape of a substantially rectangular box. The battery pack 19 is, for example, a lithium-ion battery with an output voltage of 36 V. The battery pack 19 can be removed from the battery mounting section 18 and repeatedly charged using a separately prepared charger. The battery pack 19 can be used as a power source for other rechargeable power tools such as a screwdriver or an electric drill.

As shown in Figures 1 and 2, a handle unit 20 is provided at the upper front part of the cutting machine body 10. The handle unit 20 is located to the right of the fixed cover 12 and the movable cover 13. The handle unit 20 has a loop-shaped operating handle 21 that extends along the side of the cutting tool 11. A switch lever 22 is provided on the inner circumference of the operating handle 21. The user can pull the switch lever 22 with their finger while holding the operating handle 21. Pulling the switch lever 22 starts the electric motor 15. A lock-off button 23 is provided at the top of the operating handle 21. The switch lever 22 can be pulled by pressing the lock-off button 23. This prevents the electric motor 15 from being started unexpectedly.

As shown in FIG. 1, the handle section 20 has a carrying handle 24 behind the operating handle 21. The carrying handle 24 has one end connected to the left side of the fixed cover 12 and the other end connected to the left side of the controller housing 16, forming a loop shape. The carrying handle 24 is a gripping part that the user holds when carrying the bench cutter 1 with the cutting machine body 10 locked at the bottom dead center.

As shown in FIG. 2, a turntable fixing mechanism 35 is provided at the bottom of the table extension 5. A grip portion 36 having an uneven shape on the periphery is provided at the front of the table extension 5. A user can grasp the grip portion 36 to rotate the turntable 4 horizontally relative to the base 2. A fixed rod 37 extends from the grip portion 36 toward the rear inside the table extension 5. The fixed rod 37 is supported inside the table extension 5 by a screw engagement. By rotating the grip portion 36 around the axis of the fixed rod 37, the fixed rod 37 is displaced in the front-rear direction.

As shown in FIG. 2, the base 2 has a horizontal plate portion 2c extending horizontally. A clamping member 38 is provided behind the fixed rod 37. The clamping member 38 is substantially L-shaped when viewed from the left and right sides. The clamping member 38 has a rotation shaft 38a extending left and right near the bent portion of the substantially L shape. The clamping member 38 is supported by the table extension portion 5 so as to be rotatable around the rotation shaft 38a. One end of the L shape of the clamping member 38 abuts against the rear end of the fixed rod 37, and the other end of the L shape abuts against the underside of the horizontal plate portion 2c.

When the fixed rod 37 is displaced rearward and comes into contact with the clamping member 38, the clamping member 38 rotates around the rotation axis 38a. The clamping member 38 clamps the horizontal plate portion 2c between itself and the table extension 5. As a result, the table extension 5 and the clamping member 38 cannot move left or right relative to the horizontal plate portion 2c, and are locked to the base 2. This allows the turntable 4 to be locked at a predetermined miter angle. When the fixed rod 37 is displaced forward, the force pushing the clamping member 38 rearward becomes smaller (or disappears). As a result, the clamping of the horizontal plate portion 2c by the clamping member 38 and the table extension 5 is released.

As shown in FIG. 2, a positive lock mechanism 40 is provided at the bottom of the table extension 5. The positive lock mechanism 40 has an unlocking lever 41 (see FIG. 1) and a positioning pin 41a. The unlocking lever 41 is provided on the left side of the front of the table extension 5. The positioning pin 41a extends toward the rear inside the table extension 5. The positioning pin 41a is provided at approximately the same height as the miter scale plate 7. The rear end of the positioning pin 41a can enter the positioning recess 7b by displacing rearward. The rear end of the positioning pin 41a can disengage from the positioning recess 7b by displacing forward.

The front part of the positioning pin 41a shown in FIG. 2 is connected to the unlocking lever 41 (see FIG. 1). The positioning pin 41a rotates around its axis by operating the unlocking lever 41. An engagement pin extending perpendicular to the extension direction of the positioning pin 41a is provided at approximately the center of the positioning pin 41a. The engagement pin is provided integrally with the table extension 5 and abuts against a lead surface that extends spirally in the front-rear direction. The engagement pin can be displaced in the front-rear direction along the lead surface. The positioning pin 41a is biased backward by a compression spring 41c.

When the unlocking lever 41 is pressed downward, the positioning pin 41a rotates to displace the engagement pin forward along the lead surface. The positioning pin 41a displaces forward against the biasing force of the compression spring 41c. This disengages the rear end of the positioning pin 41a from the positioning recess 7b. When the unlocking lever 41 is pulled upward, the engagement pin displaces rearward along the lead surface. The positioning pin 41a displaces rearward due to the biasing force of the compression spring 41c. The rear end of the positioning pin 41a abuts against the outer periphery of the miter scale plate 7. When the grip portion 36 is gripped and the turntable 4 is rotated horizontally, the positioning pin 41a enters one of the positioning recesses 7b provided on the outer periphery of the miter scale plate 7. Thus, the turntable 4 is positioned at a predetermined miter angle position corresponding to the positioning recess 7b.

As shown in FIG. 2, a cylindrical tilt-fix operation part 39 with an uneven shape on its periphery is provided between the grip part 36 and the front end of the table extension part 5. The tilt-fix operation part 39 can be rotated around an axis extending in the front-rear direction. The uneven shape of the tilt-fix operation part 39 is formed in a different pattern from the uneven shape of the grip part 36 so that it is easy for the user to distinguish.

As shown in FIG. 5, a transmission shaft 39a extending in the front-rear direction is provided at the bottom of the turntable 4. The front end of the transmission shaft 39a is connected to the tilt-fixing operation unit 39 via a reduction gear unit (not shown). The rotational power of the tilt-fixing operation unit 39 is reduced by the reduction gear unit to rotate the transmission shaft 39a around its axis. The rear end of the transmission shaft 39a extends to the arm side connecting unit 30b. A nut 39b that restricts the rotation of the transmission shaft 39a around its axis relative to the main body support arm 30 is fastened to the rear end of the transmission shaft 39a. When the tilt-fixing operation unit 39 is rotated to rotate the transmission shaft 39a around its axis, the axial force presses the connecting unit 51 and the arm side connecting unit 30b against each other in the front-rear direction. Therefore, the main body support arm 30 is positioned at a predetermined left-right tilt angle relative to the connecting unit 51. When the transmission shaft 39a is rotated in the opposite direction, the axial force is released. This allows the main body support arm 30 to tilt left and right around the left and right tilt support shaft 30a (see Figure 1) relative to the connecting part 51.

As shown in FIG. 1, a movable placement part 44 is provided on the left side of the table extension 5. The movable placement part 44 is a columnar shape that extends linearly in the horizontal direction. The movable placement part 44 can rotate horizontally around a support shaft 44a provided on the left side of the table extension 5. By rotating the movable placement part 44 to a leftward protruding position, the movable placement part 44 can support the workpiece W (see FIG. 2) protruding leftward from the table extension 5 from below. In addition, by rotating the movable placement part 44 to a storage position that extends in the front-rear direction along the table extension 5, the movable placement part 44 can be stored compactly. The movable placement part 44 is connected to the support shaft 44a so that the upper surface height is approximately the same height as the table upper surface 50a. At the tip of the movable placement part 44, a leg part 44b extending downward is provided. The length of the leg part 44b in the vertical direction can be adjusted by screw operation. This allows the upper surface height of the movable placement part 44 to be adjusted. It also eliminates any wobbling when installing the movable placement section 44.

As shown in FIG. 7, the turntable 4 has a cylindrical vertical wall portion 53 extending downward from the outer periphery of the top plate portion 50. As shown in FIG. 8, a cylindrical rotating shaft portion 52 extending downward is provided in the center of the underside of the top plate portion 50. The turntable 4 has a plate-shaped protrusion 54, a second protrusion 57, and a third protrusion 58 extending downward from the top plate portion 50. The protrusion 54, the second protrusion 57, and the third protrusion 58 are each provided with a substantially constant plate thickness. The top plate portion 50, the table extension portion 5, the connecting portion 51, the rotating shaft portion 52, the vertical wall portion 53, the protrusion 54, the second protrusion 57, and the third protrusion 58 are integrally molded.

As shown in FIG. 6, the rotating shaft 52 is attached to the center of the base 2 by a hexagonal bolt 2b. An adhesive is applied to the tip (lower end) of the hexagonal bolt 2b to prevent loosening of the base 2. A urethane ring 2f, a thrust needle bearing 2d, and two flat washers 2e are interposed between the head of the hexagonal bolt 2b and the rotating shaft 52. The urethane ring 2f is disposed below the thrust needle bearing 2d while being penetrated by the hexagonal bolt 2b. The thrust needle bearing 2d is sandwiched between the two flat washers 2e in the vertical direction. The turntable 4 can rotate smoothly with respect to the hexagonal bolt 2b fixed to the base 2 by the thrust needle bearing 2d. The hexagonal bolt 2b is fastened to the base 2 to such an extent that the urethane ring 2f is lightly crushed in the vertical direction. Therefore, the hexagonal bolt 2b is fastened with a substantially constant tightening amount with little variation due to the predetermined elastic force of the urethane ring 2f. As a result, a nearly constant axial force always acts on the thrust needle bearing 2d, stabilizing the rotation of the turntable 4.

As shown in FIG. 6, the lower end 53c of the vertical wall portion 53 abuts against the upper surface of the horizontal plate portion 2c provided on the base 2. When the turntable 4 rotates in the horizontal direction, the lower end 53c slides against the upper surface of the horizontal plate portion 2c.

As shown in FIG. 3, when the cutting machine body 10 is swung downward to cut the cutting tool 11 into the workpiece W, the body support arm 30 is subjected to a force pulling upward. At this time, the connecting part 51 connected to the arm side connecting part 30b is subjected to a bending stress that bends the rear side upward. The top plate part 50, which is integral with the connecting part 51, is subjected to a bending stress that bends the rear side upward.

The flow of the stress direction was simulated for a turntable 110 in which no protrusions are provided on the underside of the top plate portion 50. Figure 11 shows the analysis results of the simulation in a simplified manner. The flow of the stress direction when bending deformation is applied to the connecting portion 51 in the upward direction (in the depth direction of the paper in Figure 11) is indicated by black arrows. The flow of the stress direction goes from the connecting portion 51 to the front of the top plate portion 50, and as it goes further forward, it gradually changes direction to the left and right outward. The change in the stress direction starts roughly halfway between the rear end and the center of the top plate portion 50. The flow of the stress direction passes through the center of the top plate portion 50 and crosses at an angle with respect to a virtual plane S that extends in the left and right direction. The magnitude of the stress is larger the closer to the rear end of the top plate portion 50, and becomes smaller as it goes forward.

As shown in FIG. 10, the ridges 54 are arranged along the flow of the stress direction. The ridges 54 are provided symmetrically with respect to the cutting tool 11, one on each side of the top plate 50. The ridges 54 have a rear ridge 55 that intersects with the rear front surface of the vertical wall 53 and extends linearly in the front-to-rear direction, and an arc-shaped front ridge 56 that is connected to the front end 55a of the rear ridge 55 and extends forward.

As shown in FIG. 10, the rear of the rear ridge 55 extends further rearward from the vertical wall intersection 55c where it intersects with the vertical wall 53. The rear ridge 55 extends along the left or right side of the cylindrical connecting portion 51, approaching the center of the connecting portion 51 as it moves rearward outside the vertical wall 53. The rear end 55b of the rear ridge 55 is connected to the left or right side of the connecting portion 51. The front end 55a of the rear ridge 55 is located midway between the rear end of the top plate 50 and the imaginary plane S in the front-to-rear direction. The rear ridge 55 extends in a direction substantially perpendicular to the imaginary plane S between the front end 55a and the vertical wall intersection 55c.

As shown in FIG. 10, the rear end 56b of the front ridge 56 is connected to the front end 55a of the rear ridge 55. The front end 56a of the front ridge 56 is connected to the front rear surface of the vertical wall portion 53. The front ridge 56 extends forward from the rear end 56b to the front end 56a and extends outward to the left and right away from the cutting tool 11. The front ridge 56 forms a smooth arc-shaped curve in a plan view. The radius of curvature of the front ridge 56 is approximately the same as the radius of curvature of the vertical wall portion 53. The front ridge 56 intersects with an imaginary plane S perpendicular to the cutting tool 11 at a central intersection 56c located halfway between the rear end 56b and the front end 56a. The front ridge 56 intersects with the imaginary plane S at an angle of 10° to 80° at the central intersection 56c, preferably at an angle of 40° to 60°.

As shown in Figures 8 and 9, the rear ridge 55 is provided at approximately the same vertical height between the front end 55a and the vertical wall intersection 55c. The rear ridge 55 is provided at approximately the same height between the vertical wall intersection 55c and the rear end 55b, but is formed so that its height decreases toward the rear only near the rear end 55b. The front ridge 56 is formed so that its height gradually decreases from the rear end 56b toward the front end 56a. The height of the front ridge 56 at the front end 56a is approximately half the height of the front ridge 56 at the rear end 56b.

As shown in Figures 8 to 10, the second ridge 57 extends linearly from the center of the top plate portion 50 toward the rear and away from the cutting tool 11. The front end 57a of the second ridge 57 is connected to the rear surface of the rotating shaft portion 52. The rear end 57b of the second ridge 57 is connected to the rear front surface of the vertical wall portion 53. The second ridge 57 intersects with the ridge 54 at a ridge intersection portion 57c located halfway between the front end 57a and the rear end 57b. The ridge intersection portion 57c is located near the rear end 56b (front end 55a). The second ridge 57 extends in a direction at an angle of, for example, 30° to 60° with respect to the imaginary plane S. The second ridge 57 intersects with the ridge 54 at a relatively large angle, for example close to a right angle.

As shown in Figures 8 to 10, the third ridge 58 extends linearly from the center of the top plate portion 50 toward the rear. The front end 58a of the third ridge 58 is connected to the rear surface of the left or right end of the rotating shaft portion 52. The front end 58a is located near the front end 57a. The rear end 58b of the third ridge 58 is connected to the rear front surface of the vertical wall portion 53. The third ridge 58 is located in the central region of the top plate portion 50, closer to the cutting tool 11 than the ridge 54. The third ridge 58 extends in a direction generally perpendicular to the imaginary plane S.

As described above, the bench cutter 1 has a cutting machine body 10 that rotatably supports the disk-shaped cutting tool 11 in a position extending in the front-rear direction as shown in Figures 2 and 5, and a turntable 4 that supports the cutting machine body 10 so that it can move in the vertical direction. The turntable 4 is provided with a disk-shaped top plate portion 50 on which the workpiece W is placed on the table top surface 50a, and a connecting portion 51 to which the cutting machine body 10 is connected at the rear of the top plate portion 50. A rotating shaft portion 52 that extends downward from the center of the lower surface of the top plate portion 50 and is rotatably attached to the base 2, and a vertical wall portion 53 that extends downward from the outer periphery of the top plate portion 50 and has a lower end 53c that slides against the base 2 are provided. A pair of protrusions 54 are provided on the lower surface of the top plate portion 50, extending forward from the rear front surface of the vertical wall portion 53. The protrusions 54 have rear protrusions 55 that extend in the front-rear direction in either the left or right region of the rotating shaft portion 52. The ridge 54 has a front ridge 56 that extends further forward from the front end 55a of the rear ridge 55 in a direction away from the cutting tool 11 and reaches a front region forward of the rotating shaft portion 52.

Therefore, the rigidity of the turntable 4 can be increased by the protrusion 54 provided on the underside of the top plate 50. The protrusion 54 has a rear protrusion 55 that protrudes forward from the rear of the turntable 4, and a front protrusion 56 that extends further forward from the front end 55a of the rear protrusion 55 and in a direction away from the cutting tool 11. Therefore, the protrusion 54 extends along the flow of the stress direction of the bending stress that the turntable 4 receives when the connecting portion 51 is pulled upward. Therefore, the bending deformation of the turntable 4 can be efficiently suppressed by the protrusion 54. Moreover, the front protrusion 56 extends to the front area of the top plate 50 on which the workpiece W is placed. Therefore, the rigidity of the front area of the top plate 50 can be improved. Therefore, the horizontality of the upper surface can be maintained in the front area of the top plate 50. As a result, the workpiece W can be placed in a stable position on the table top surface 50a of the top plate 50.

As shown in FIG. 10, the front end 56a of the front protrusion 56 is connected to the vertical wall portion 53. This further improves the rigidity of the front region of the turntable 4. This increases the stability of the workpiece W placed on the table top surface 50a (see FIG. 2) in the front region of the top plate portion 50.

As shown in FIG. 10, the front protrusion 56 extends in an arc shape away from the cutting tool 11. Therefore, the arc shape of the front protrusion 56 is closer to the flow of the bending stress that the turntable 4 receives. This makes it possible to improve the rigidity of the turntable 4 without significantly changing the total weight of the protrusion 54.

As shown in FIG. 10, the front protrusion 56 intersects with an imaginary plane S that passes through the center of the rotating shaft 52 and extends in the left-right direction at an angle of 10° to 80°. The front protrusion 56 is therefore provided across the rear region of the turntable 4 behind the imaginary plane S and the front region of the turntable 4 in front of the imaginary plane S. The flow of the stress direction has already changed direction to move away from the cutting tool 11 behind the imaginary plane S. Therefore, by providing the front protrusion 56 along the flow of the stress direction, the rigidity of both the rear region and the front region of the turntable 4 can be improved.

As shown in Figures 8 to 10, the rear protrusion 55 extends so as to intersect with the vertical wall portion 53, and the rear end 55b of the rear protrusion 55 is connected to the connecting portion 51. The rear protrusion 55 is therefore connected to the top plate portion 50, the vertical wall portion 53, and the connecting portion 51. Therefore, the rigidity of the vertical wall portion 53 and the connecting portion 51 can be utilized to improve the rigidity of the top plate portion 50 on which the rear protrusion 55 is provided.

As shown in Figures 8 to 10, the connecting portion 51 is tubular and extends in the front-to-rear direction. The rear protrusion 55 extends along either the left or right side surface of the connecting portion 51. The rear protrusion 55 is therefore connected to the connecting portion 51 along the left or right side surface of the connecting portion 51 that extends in the front-to-rear direction. This makes it possible to increase the rigidity of the rear protrusion 55 in the front-to-rear direction. The rear protrusion 55 is connected to the underside of the top plate portion 50, extending in the front-to-rear direction. This makes it possible to improve the rigidity of the top plate portion 50 to which the rear protrusion 55 is connected.

As shown in Figures 8 and 9, the front protrusion 56 extends from the front end of the rear protrusion 55 and decreases in height in the vertical direction. Therefore, the vertical height of the front protrusion 56 can be changed according to the rigidity required at each position on the turntable 4. The bending stress that the turntable 4 receives decreases from the rear to the front. Therefore, the weight of the turntable 4 can be reduced while ensuring the rigidity required at each position on the turntable 4.

As shown in Figures 8 to 10, the turntable 4 has a second ridge 57 that extends rearward from the rear surface of the rotating shaft 52 on the underside of the top plate 50 in a direction away from the cutting tool 11. The second ridge 57 intersects with the ridge 54. Therefore, the second ridge 57 intersects with the ridge 54 at a relatively large angle. Therefore, by having the ridge 54 and the second ridge 57 work together, the rigidity of a wide area in the rear region of the turntable 4 can be increased.

As shown in FIG. 10, the turntable 4 has a third ridge 58 that extends in the front-rear direction in an area closer to the cutting tool 11 than the ridge 54. The third ridge 58 therefore further increases the rigidity of the center of the turntable 4. Moreover, the third ridge 58 can be provided along the flow of the stress direction. This further suppresses bending deformation of the top plate portion 50.

Next, a second embodiment of the present disclosure will be described with reference to FIG. 12. A bench cutter 60 of the second embodiment has a turntable 61 instead of the turntable 4 shown in FIG. 10. A plate-shaped protrusion 62 extending downward is provided on the underside of the top plate portion 50 of the turntable 61. The protrusion 62 is integrally formed with other components of the turntable 4, such as the top plate portion 50, the connecting portion 51, and the vertical wall portion 53. Although the second protrusion 57 and the third protrusion 58 are not shown in the following embodiments, either or both of the second protrusion 57 and the third protrusion 58 may be provided on the underside of the top plate portion 50.

As shown in FIG. 12, the protrusions 62 are provided symmetrically with respect to the cutting tool 11 (see FIG. 10), one on each side of the top plate 50. The protrusions 62 have a rear protrusion 63 that intersects with the rear of the vertical wall 53 and extends linearly in the front-rear direction, and an arc-shaped front protrusion 64 that is connected to the front end 63a of the rear protrusion 63 and extends forward. The rear of the rear protrusion 63 extends further rearward from the vertical wall intersection 63c that intersects with the vertical wall 53. The rear end 63b of the rear protrusion 63 is connected to the left or right side of the connection portion 51. The front end 63a of the rear protrusion 63 is located midway between the rear end of the top plate 50 and the imaginary plane S in the front-rear direction.

As shown in FIG. 12, the rear end 64b of the front protrusion 64 is connected to the front end 63a of the rear protrusion 63. The front end 64a of the front protrusion 64 is located halfway between the front end of the top plate portion 50 and the imaginary plane S. In other words, the front protrusion 64 is not connected to the vertical wall portion 53. The front protrusion 64 extends forward from the rear end 64b to the front end 64a and extends in an arc shape outward to the left and right away from the cutting tool 11 (see FIG. 10). The front protrusion 64 intersects with the imaginary plane S at a central intersection 64c located halfway between the rear end 64b and the front end 64a. The front protrusion 64 intersects with the imaginary plane S at an angle of 10° to 80° at the central intersection 64c, preferably at an angle of 40° to 60°.

Next, a third embodiment of the present disclosure will be described with reference to FIG. 13. A bench cutter 70 of the third embodiment has a turntable 71 instead of the turntable 4 shown in FIG. 10. A plate-shaped ridge 72 extending downward is provided on the underside of the top plate portion 50 of the turntable 71. The ridge 72 is molded integrally with the other components of the turntable 4.

As shown in FIG. 13, the ridges 72 are provided symmetrically with respect to the cutting tool 11 (see FIG. 10), one on each side of the top plate 50. The ridges 72 have a rear ridge 73 that intersects with the rear of the vertical wall 53 and extends linearly in the front-to-rear direction, and a front ridge 74 that is connected to the front end 73a of the rear ridge 73 and extends linearly forward. The shape of the rear ridge 73 and the positions of the front end 73a, rear end 73b, and vertical wall intersection 73c are the same as those of the rear ridge 63 shown in FIG. 12.

As shown in FIG. 13, the rear end 74b of the front ridge 74 is connected to the front end 73a of the rear ridge 73. The front end 74a of the front ridge 74 is connected to the front rear surface of the vertical wall portion 53. The front ridge 74 extends forward from the rear end 74b to the front end 74a and linearly extends outward to the left and right away from the cutting tool 11 (see FIG. 10). Therefore, the front ridge 74 is curved with respect to the rear ridge 73. The front ridge 74 intersects with the imaginary plane S at an angle of 10° to 80° at a central intersection 74c located halfway between the rear end 74b and the front end 74a at an angle of 40° to 60°.

Next, a fourth embodiment of the present disclosure will be described with reference to FIG. 14. A bench cutter 80 of the fourth embodiment has a turntable 81 instead of the turntable 4 shown in FIG. 10. A plate-shaped ridge 82 extending downward is provided on the underside of the top plate portion 50 of the turntable 81. The ridge 82 is molded integrally with the other components of the turntable 4.

As shown in FIG. 14, the ridges 82 are provided symmetrically with respect to the cutting tool 11 (see FIG. 10), one on each side of the top plate 50. The ridges 82 have a rear ridge 83 that intersects with the rear of the vertical wall 53 and extends linearly in the front-to-rear direction, and a front ridge 84 that is connected to the front end 83a of the rear ridge 83 and extends forward. The shape of the rear ridge 83 and the positions of the front end 83a, rear end 83b, and vertical wall intersection 83c are the same as those of the rear ridge 63 shown in FIG. 12.

As shown in FIG. 14, the rear end 84b of the front protrusion 84 is connected to the front end 83a of the rear protrusion 83. The front end 84a of the front protrusion 84 is connected to the front rear surface of the vertical wall portion 53. The front protrusion 84 has a straight portion 84e that extends linearly and a curved portion 84d that extends in an arc shape. The straight portion 84e is provided in the area from the rear end 84b to the midpoint between the front end of the top plate portion 50 and the imaginary plane S. The straight portion 84e extends forward and linearly extends outward to the left and right away from the cutting tool 11 (see FIG. 11). Therefore, the straight portion 84e is provided curved with respect to the rear protrusion 83. The curved portion 84d is provided in the area from the front end of the straight portion 84e to the front end 84a. The curved portion 84d extends forward and extends in an arc shape outward to the left and right away from the cutting tool 11. The front protrusion 84 intersects with the imaginary plane S at an angle of 10° to 80° at the central intersection 84c located halfway between the straight line portions 84e, and preferably at an angle of 40° to 60°.

Next, a fifth embodiment of the present disclosure will be described with reference to FIG. 15. A bench cutter 90 of the fifth embodiment has a turntable 91 instead of the turntable 4 shown in FIG. 10. The bottom surface of the top plate portion 50 of the turntable 91 is provided with plate-shaped inner ridges 92 and outer ridges 95 that extend downward. The inner ridges 92 and outer ridges 95 are molded integrally with the other components of the turntable 4.

As shown in FIG. 15, the inner ridge 92 and the outer ridge 95 are provided symmetrically with respect to the cutting tool 11 (see FIG. 10), one on each side of the top plate 50. The inner ridge 92 has a rear ridge 93 that intersects with the rear of the vertical wall 53 and extends linearly in the front-rear direction, and a front ridge 94 that is connected to the front end 93a of the rear ridge 93 and extends forward in an arc. The rear of the rear ridge 93 extends further rearward from the vertical wall intersection 93c that intersects with the vertical wall 53. The rear end 93b of the rear ridge 93 is connected to the left or right side of the connection portion 51. The front end 93a of the rear ridge 93 is located midway between the rear end of the top plate 50 and the imaginary plane S in the front-rear direction.

As shown in FIG. 15, the rear end 94b of the front ridge 94 is connected to the front end 93a of the rear ridge 93. The front end 94a of the front ridge 94 is connected to the front rear surface of the vertical wall portion 53. The front ridge 94 extends forward from the rear end 94b to the front end 94a and extends in an arc shape outward to the left and right away from the cutting tool 11 (see FIG. 10). The front ridge 94 intersects with the imaginary plane S at a central intersection 94c located halfway between the rear end 94b and the front end 94a. The front ridge 94 intersects with the imaginary plane S at the central intersection 94c at an angle of 10° to 80°, preferably at an angle of 40° to 60°.

As shown in FIG. 15, the outer ridge 95 is located farther from the cutting tool 11 (see FIG. 10) than the inner ridge 92. The right outer ridge 95 is located to the right of the right inner ridge 92. The left outer ridge 95 is located to the left of the left inner ridge 92. The outer ridge 95 has a rear ridge 96 that is connected to the rear front surface of the vertical wall portion 53 and extends linearly in the front-rear direction, and a front ridge 97 that is connected to the front end 96a of the rear ridge 96 and extends forward in an arc. The front end 96a of the rear ridge 96 is located at approximately the same front-rear position as the front end 93a. The rear ridge 96 extends approximately parallel to the rear ridge 93. The rear end 96b of the rear ridge is connected to the rear front surface of the vertical wall portion 53 at a position farther from the cutting tool 11 than the rear ridge 93.

As shown in FIG. 15, the rear end 97b of the front ridge 97 is connected to the front end 96a of the rear ridge 96. The front end 97a of the front ridge 97 is connected to the front rear surface of the vertical wall portion 53. The front ridge 97 extends forward from the rear end 97b to the front end 97a and extends in an arc shape outward to the left and right away from the cutting tool 11 (see FIG. 10). The right (left) front ridge 97 extends approximately parallel to the right (left) front ridge 94. The front ridge 97 intersects with the imaginary plane S at an angle of 10° to 80°, preferably 40° to 60°, at a central intersection 97c located halfway between the rear end 97b and the front end 97a.

Next, a sixth embodiment of the present disclosure will be described with reference to FIG. 16. The bench cutter 100 of the sixth embodiment has a turntable 101 instead of the turntable 4 shown in FIG. 10. A plate-shaped protrusion 102 extending downward is provided on the underside of the top plate portion 50 of the turntable 101. The protrusion 102 is molded integrally with the other components of the turntable 4.

As shown in FIG. 16, the ridges 102 are provided symmetrically with respect to the cutting tool 11 (see FIG. 10), one on each side of the top plate 50. The ridges 102 have a rear ridge 103 that intersects with the rear of the vertical wall 53 and extends linearly in the front-to-rear direction, and a front ridge 104 that is connected to the front end 103a of the rear ridge 103 and extends linearly forward.

As shown in FIG. 16, the rear of the rear protrusion 103 extends further rearward from the vertical wall intersection 103c where it intersects with the vertical wall 53. The rear end 103b of the rear protrusion 103 is connected to the left or right side of the connecting portion 51. The front end 103a of the rear protrusion 103 is located midway between the rear end of the top plate 50 and the imaginary plane S in the front-to-rear direction. The rear protrusion 103 extends linearly from the vertical wall intersection 103c toward the front end in a direction approaching the cutting tool 11 (see FIG. 10).

As shown in FIG. 16, the rear end 104b of the front protrusion 104 is connected to the front end 103a of the rear protrusion 103. The front end 104a of the front protrusion 104 is connected to the front rear surface of the vertical wall portion 53. The front protrusion 104 extends forward from the rear end 104b to the front end 104a and linearly extends outward to the left and right away from the cutting tool 11 (see FIG. 10). Therefore, the front protrusion 104 is curved with respect to the rear protrusion 103. The front protrusion 104 intersects with the imaginary plane S at an angle of 10° to 80° at the central intersection 104c located halfway between the rear end 104b and the front end 104a at an angle of 40° to 70°.

Various modifications can be made to the bench cutters of the embodiments described above. Instead of the sliding circular saws exemplified in this disclosure, for example, the present disclosure may be applied to bench cutters that do not have a sliding function for the cutter body.

The configuration in which the protrusions are provided symmetrically on the top plate portion 50 has been exemplified. Alternatively, the protrusions may be provided asymmetrically on the top plate portion 50. For example, protrusions may be provided only on one of the left and right sides of the top plate portion 50. Alternatively, the shape and number of protrusions may differ between the left and right sides of the top plate portion 50. A rear protrusion that connects to the vertical wall portion 53 has been exemplified. Alternatively, a rear protrusion that is not connected to the vertical wall portion 53 may be applied. A rear protrusion that does not have a curved portion and extends linearly has been exemplified. Alternatively, the rear protrusion may include a portion that is curved or linear.

The example shows a front protrusion that is curved in an arc or a straight line. Alternatively, the protrusion may be curved in another curved shape, such as a parabola. The example shows a plate-shaped protrusion of approximately constant thickness. Alternatively, the protrusion may be configured so that its thickness increases toward the rear. The example shows a second protrusion 57 and a third protrusion 58 that extend from the rear surface of the rotating shaft 52 to the rear front surface of the vertical wall 53. Alternatively, for example, the second protrusion 57 or the third protrusion 58 may not be connected to the vertical wall 53. The shape of the rotating shaft 52 is not limited to a cylindrical shape, and may be, for example, a columnar shape, a polygonal shape, or the like.

1...Benchtop cutting machine (first embodiment)
2...base, 2a...table rotation shaft, 2b...hexagonal bolt, 2c...horizontal plate portion 2d...thrust needle bearing, 2e...flat washer, 2f...urethane ring 3...auxiliary table 4...turntable 5...table extension portion, 5a...cutting edge plate, 5b...slot 6...positioning fence, 6a...positioning surface 7...miter scale plate, 7a...fixing screw, 7b...positioning recess 10...cutting machine body, 10a...up and down swing shaft 11...cutting tool 12...fixed cover, 12a...arrow 13...movable cover 14...motor housing 15...electric motor 16...controller housing 17...controller 18...battery mounting portion 19...battery pack 20...handle portion 21...operation handle 22...switch lever 23...lock-off button 24...carrying handle 30...main body support arm, 30a...left and right tilt shaft, 30b...arm side Connecting portion 31...slide bar 32...slide base 35...turntable fixing mechanism 36...grip portion 37...fixing rod 38...clamping member, 38a...rotation shaft 39...tilt fixing operation portion, 39a...transmission shaft, 39b...nut 40...positive lock mechanism 41...lock release lever, 41a...positioning pin, 41c...compression spring 43...adjusting bolt 44...movable mounting portion, 44a...support shaft, 44b...leg portion 50... Table top portion, 50a...table upper surface 51...connecting portion 52...rotating shaft portion 53...vertical wall portion, 53c...lower end 54...rib 55...rear rib, 55a...front end, 55b...rear end, 55c...vertical wall intersection portion 56...front rib, 56a...front end, 56b...rear end, 56c...central intersection portion 57...second rib, 57a...front end, 57b...rear end, 57c...rib intersection portion 58...third rib, 58a...front end, 58b...rear end 60...benchtop cutting machine (second embodiment)
61... turntable 62... ridge 63... rear ridge, 63a... front end, 63b... rear end, 63c... vertical wall intersection 64... front ridge, 64a... front end, 64b... rear end, 64c... central intersection 70... bench cutter (third embodiment)
71: turntable 72: ridge 73: rear ridge, 73a: front end, 73b: rear end, 73c: vertical wall intersection 74: front ridge, 74a: front end, 74b: rear end, 74c: central intersection 80: bench cutter (fourth embodiment)
81... turntable 82... ridge 83... rear ridge, 83a... front end, 83b... rear end, 83c... vertical wall intersection 84... front ridge, 84a... front end, 84b... rear end, 84c... central intersection 84d... curved portion, 84e... straight portion 90... bench cutter (fifth embodiment)
91... turntable 92... inner ridge 93... rear ridge, 93a... front end, 93b... rear end, 93c... vertical wall intersection 94... front ridge, 94a... front end, 94b... rear end, 94c... central intersection 95... outer ridge (first ridge)
96: rear protrusion, 96a: front end, 96b: rear end 97: front protrusion, 97a: front end, 97b: rear end, 97c: central intersection 100: bench cutter (sixth embodiment)
101... turntable 102... ridge 103... rear ridge, 103a... front end, 103b... rear end, 103c... vertical wall intersection 104... front ridge, 104a... front end, 104b... rear end, 104c... central intersection 110... turntable W... workpiece S... imaginary plane

Claims (9)

A benchtop cutting machine,
A cutting machine body that rotatably supports a disk-shaped cutting tool in a position that extends in the front-rear direction;
The cutter body has a turntable that supports the cutter body so as to be movable in the vertical direction, and the turntable has
A disk-shaped top plate portion on which a workpiece is placed;
a connecting portion to which the cutting machine body is connected at a rear portion of the top plate portion;
a rotation shaft portion extending downward from the center of the lower surface of the top plate portion and rotatably attached to a base;
a vertical wall portion having a lower end extending downward from an outer circumferential edge of the top plate portion and sliding relative to the base;
The lower surface of the top plate portion has at least one protrusion extending forward from an inner wall surface facing forward at the rear of the vertical wall portion, and the protrusion
a rear protrusion extending in a front-rear direction in either a left or right region of the rotary shaft portion;
A bench cutter having a front protrusion that extends further forward from the front end of the rear protrusion and extends in a direction away from an imaginary plane extending from the side of the cutting tool in a vertically upright position as it moves forward until it reaches a front end located in a front region forward of the rotating shaft portion. 2. The bench cutter according to claim 1,
A bench cutter, wherein the front end of the front protrusion is connected to the vertical wall portion. The bench cutter according to claim 1 or 2,
The front protrusion extends in an arc shape in a direction away from the imaginary plane . A bench cutter according to any one of claims 1 to 3,
The front protrusion intersects with a second imaginary plane that passes through the center of the rotating shaft and extends in the left-right direction at an angle of 10° to 80°. A bench cutter according to any one of claims 1 to 4,
The rear protrusion extends so as to intersect with the vertical wall portion, and a rear end of the rear protrusion is connected to the connecting portion. The bench cutter according to claim 5,
The connecting portion has a cylindrical shape extending in the front-rear direction,
The rear protrusion extends along either the left or right side surface of the connecting portion. A bench cutter according to any one of claims 1 to 6,
The front protrusion extends from the front end of the rear protrusion and decreases in height in the vertical direction. A bench cutter according to any one of claims 1 to 7,
The turntable has a second protrusion on the underside of the top plate portion, the second protrusion extending rearward from the rear surface of the rotating shaft portion and in a direction away from the imaginary plane , and the second protrusion intersects with the first protrusion. A bench cutter according to any one of claims 1 to 7,
The turntable has a third ridge extending in the front-rear direction in an area closer to the imaginary plane than the ridge.

Images