JP2016187842A - Desktop cutter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a desktop cutter capable of surely returning a sub-cover to an initial position, when rocking a cutting part so as to separate from a base part.SOLUTION: A cutting part 11 is journaled to a circular saw part holder 7 via a shaft 10. A circular saw blade 18 is rotatably supported by the cutting part 11. The cutting part 11 comprises a saw cover 11b for covering the upper outer periphery of the circular saw blade 18, a protective cover 28 and a sub-cover 40 for covering the lower outer periphery of the circular saw blade 18. A hinge arm 43 is fixed to the circular saw part holder 7 by screw-fastening. The tip of the hinge arm 43 is provided with an arm pin 44 engageable with the sub-cover 40. The arm pin 44 is positioned on a rotary range of the sub-cover 40. When a malfunction of the sub-cover 40 is caused, the arm pin 44 abuts on the sub-cover 40, and forcedly returns the sub-cover 40 to an original position in the middle when the cutting part 11 returns to an upper limit position.SELECTED DRAWING: Figure 5

Description

  The present invention relates to a tabletop cutting machine that cuts a workpiece with a cutting blade such as a circular saw blade.

  A tabletop cutting machine generally includes a base portion and a cutting portion (a circular saw portion) that is swingably supported by the base portion. The cutting unit includes an electric motor that rotationally drives a cutting blade such as a circular saw blade. The user swings the cutting portion rotating the cutting blade downward, and cuts the workpiece placed on the base portion. The upper outer periphery of the cutting blade is covered with a saw cover, and the lower outer periphery of the cutting blade is covered with a protective cover and a sub cover. The protective cover is connected to the saw cover by a link mechanism, and rotates upward (in the direction in which the cutting blade is exposed) when the cutting portion swings downward. The sub-cover is pivotally supported by the rear portion of the saw cover, and when the cutting portion swings downward, it rotates upward with respect to the saw cover while contacting the workpiece.

Japanese Utility Model Publication No. 3-108407

  In the conventional tabletop cutting machine, when the cutting operation is finished and the cutting part is swung upward, the sub cover is rotated downward with respect to the saw cover by its own weight and covers a part of the lower outer periphery of the cutting blade. It will return to the position. However, if chips of work material adhere to the movable mechanism part of the sub-cover during cutting work, the sub-cover may malfunction and the sub-cover may not return to the initial position even if the cutting part is swung upward. There is.

  Further, in the conventional tabletop cutting machine, when a force is applied to the sub cover from below when the cutting portion is at a position other than the upper limit, the sub cover rotates upward and the cutting blade is inadvertently exposed. There was a possibility.

  The present invention has been made in view of such a situation, and its first object is to reliably return the sub-cover to the initial position when the cutting portion is swung away from the base portion. Is to provide a simple tabletop cutting machine.

  The second object of the present invention is to provide a tabletop cutting machine capable of suppressing the sub-cover from moving carelessly and exposing the cutting blade.

The first aspect of the present invention is a tabletop cutting machine. This tabletop cutting machine
A base portion having a placement surface on which a workpiece can be placed;
A cutting part that rotatably supports the cutting blade;
A holder portion that swingably supports the cutting portion so as to be close to and away from the base portion;
The cutting portion includes a saw cover that covers an upper outer periphery of the cutting blade, a protective cover and a sub-cover that covers a lower outer periphery of the cutting blade,
The protective cover rotates around the rotation axis of the cutting blade in conjunction with the swinging of the cutting portion,
When the sub cover swings the cutting part toward the base part, the sub cover moves relative to the saw cover while contacting the workpiece on the mounting surface.
The holder part has an engaging member that can engage with the sub-cover;
The engaging member may come into contact with the sub cover to return the sub cover to an initial position covering the lower outer periphery of the cutting blade when the cutting portion is swung away from the base portion. it can.

  When the engaging member swings the cutting portion away from the base portion, the sub-cover is subject to its own weight, or the urging force that urges the own weight and itself toward the base portion side. If it is not possible to return to the initial position, the sub cover may be returned to the initial position by contacting the sub cover.

  When the relative movement of the sub-cover with respect to the saw cover is hindered when the engaging member swings the cutting portion away from the base portion, the engaging member contacts the sub-cover to You may return to the said initial position.

  When the sub-cover is in a first swing range separated from the base portion and a force is applied to the sub-cover to make a relative movement in a direction away from the base portion, Relative movement in a direction away from the base portion by engaging with the protective cover may be restricted.

  The sub cover may not engage with the protective cover when the cutting portion swings toward the base portion beyond the first swing range.

  When the cutting portion is within a second swing range that is a part of the swing range in which the sub cover does not engage the protective cover, the sub cover moves relative to the sub cover in a direction away from the base portion. When a force to be applied is applied, relative movement of the sub cover in a direction away from the base portion may be restricted by the engagement member.

The second aspect of the present invention is a tabletop cutting machine. This tabletop cutting machine
A base portion having a placement surface on which a workpiece can be placed;
A cutting part that rotatably supports the cutting blade;
A holder portion that swingably supports the cutting portion so as to be close to and away from the base portion;
The cutting portion includes a saw cover that covers an upper outer periphery of the cutting blade, a protective cover and a sub-cover that covers a lower outer periphery of the cutting blade,
The protective cover rotates around the rotation axis of the cutting blade in conjunction with the swinging of the cutting portion,
When the sub cover swings the cutting part toward the base part, the sub cover moves relative to the saw cover while contacting the workpiece on the mounting surface.
The holder part has an engaging member that can engage with the sub-cover;
When the cutting portion is within a second swing range that is a part of the swing range in which the sub cover does not engage the protective cover, the sub cover moves relative to the sub cover in a direction away from the base portion. When a force to be applied is applied, the engagement member restricts relative movement of the sub cover in a direction away from the base portion.

  The second swing range is a swing in which the sub cover comes into contact with a workpiece having a maximum height that can be cut by the tabletop cutting machine from a swing position where the sub cover does not engage with the protective cover. It may be a range up to the position.

  An urging means for urging the sub cover toward the base portion side may be provided.

  The sub cover may be rotatably supported by the saw cover, and the relative movement may be a rotation.

  The holder part may have a guide bar extending in parallel with the placement surface, and the cutting part may be movable in the extending direction of the guide bar by the support of the guide bar.

  The holder part may be connected to the base part via an inclination axis extending in parallel with the mounting surface, and may be inclined with respect to the base part using the inclination axis as a fulcrum.

  The base portion includes a base and a turntable rotatably provided on the base via a rotation shaft orthogonal to the placement surface, and the holder portion is configured to turn the turn via the inclined shaft. It may be connected to a table.

  It should be noted that any combination of the above-described constituent elements, and those obtained by converting the expression of the present invention between methods and systems are also effective as aspects of the present invention.

  According to the first aspect of the present invention, it is possible to provide a tabletop cutting machine that can reliably return the sub cover to the initial position when the cutting portion is swung away from the base portion.

  According to the second aspect of the present invention, it is possible to provide a tabletop cutting machine capable of suppressing the sub cover from moving carelessly and exposing the cutting blade.

The side view of the state which has the cutting part 11 in an upper limit position of the tabletop cutting machine which concerns on embodiment of this invention. The front view of the said tabletop cutting machine. AA sectional drawing of FIG. BB sectional drawing of FIG. CC sectional drawing of FIG. The enlarged side view of the cutting part 11 when the cutting part 11 of the said tabletop cutting machine rocks | fluctuates below from an upper limit position, and the protective cover 28 and the sub cover 40 do not overlap. The expanded side view of the cutting part 11 of the state rock | fluctuated further downward from the state of FIG. FIG. 8 is an enlarged side view of the cutting part 11 when it swings further downward from the state of FIG. 7 and the engagement with the arm pin 44 is released. The side view of the state which rock | fluctuated the cutting part 11 to the minimum position of the said tabletop cutting machine. The side view at the time of slide cutting | disconnection of the said tabletop cutting machine. The expanded side view of the cutting part 11 when the sub cover 40 becomes malfunctioning in the desktop cutting machine of a comparative example.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. In addition, the same code | symbol is attached | subjected to the same or equivalent component, member, etc. which are shown by each drawing, and the overlapping description is abbreviate | omitted suitably. In addition, the embodiments do not limit the invention but are exemplifications, and all features and combinations thereof described in the embodiments are not necessarily essential to the invention.

  FIG. 1 is a side view of the tabletop cutting machine according to the embodiment of the present invention in a state where the cutting unit 11 is at the upper limit position. With reference to FIG. 1, the front, rear, top and bottom directions are defined. FIG. 2 is a front view of the tabletop cutting machine. 3 is a cross-sectional view taken along the line AA in FIG. 4 is a cross-sectional view taken along line BB in FIG. 5 is a cross-sectional view taken along the line CC of FIG. FIG. 6 is an enlarged side view of the cutting unit 11 when the cutting unit 11 of the tabletop cutting machine swings downward from the upper limit position so that the protective cover 28 and the sub cover 40 do not overlap. FIG. 7 is an enlarged side view of the cutting part 11 in a state of swinging further downward from the state of FIG. FIG. 8 is an enlarged side view of the cutting part 11 when it swings further downward from the state of FIG. 7 and the engagement with the arm pin 44 is released. FIG. 9 is a side view of the tabletop cutting machine in a state where the cutting unit 11 is swung to the lower limit position. FIG. 10 is a side view of the tabletop cutting machine at the time of slide cutting. In the following description, the clockwise direction and the counterclockwise direction are rotation directions in the side view shown in FIG.

  In the tabletop cutting machine of the present embodiment, the workpiece 35 such as wood is placed on the upper surface of the base portion. The base portion includes a base 1 that can be placed on a floor surface and the like, and a turntable 2 that is embedded in the center of the base 1 and whose upper surface is substantially flush with the upper surface of the base 1. The turntable 2 is rotatably connected to the base 1 via a rotation shaft (not shown) orthogonal to the upper surface of the turntable 2. A pair of fences 3 is provided on the upper surface of the base 1, and a stable cutting operation can be performed by bringing the workpiece 35 into contact with the fence 3. When the turntable 2 is rotated with respect to the base 1, the positions of a holder 5 and a cutting part 11 (described later) connected to the turntable 2 with respect to the fence 3 change. As a result, the angle between the fence 3 and the side surface of the circular saw blade 18 (the angle seen from above) changes, and the workpiece 35 abutted on the fence 3 is cut (angle cut) at various angles. Can do.

  In the vicinity of the rear end (left side in FIG. 1) of the turntable 2, a holder 5 is erected upward. The holder 5 is connected to the turntable 2 via a holder shaft (inclined shaft) 4 extending substantially parallel to the side surface of the circular saw blade 18 as a cutting tool (cutting blade) and the upper surface of the turntable 2. By making the axis of the holder shaft 4 substantially coincide with the upper surface of the turntable 2, the holder 5 is pivotally supported with respect to the turntable 2 so that the holder shaft 4 can be tilted to the left and right. In the rear part of the turntable 2, a long hole 2a (FIG. 2) centering on the holder shaft 4 is formed. The clamp lever 30 passes through the long hole 2 a, and a screw portion (not shown) formed at the tip of the clamp lever 30 is screwed into a screw hole portion formed on the back surface of the holder 5. When the clamp lever 30 is loosened, the holder 5 tilts within the range of the long hole 2a with the holder shaft 4 as a fulcrum (the tilt position of the holder 5 can be adjusted). When the clamp lever 30 is tightened, the turntable 2 is tightened between the clamp lever 30 and the holder 5, and the tilt position of the holder 5 is fixed at an arbitrary position. In addition, in the example of FIG. 2, the long hole 2a is formed in the range in which the holder 5 can incline about 45 degrees right and left.

  Fixed to the upper part of the holder 5 are rear end portions of two guide bars 6 extending parallel to the holder shaft 4 (parallel to the upper surface of the base portion). A support 8 that supports the guide bar 6 is provided at the front end of the guide bar 6. Between the holder 5 of the guide bar 6 and the support 8, the circular saw holder 7 is supported so as to be slidable along the guide bar 6. Specifically, the two guide bars 6 pass through two through holes (not shown) of the circular saw part holder 7 so that the circular saw part holder 7 can slide back and forth. The holder 5 and the circular saw part holder 7 are examples of the holder part of the present invention. A slide position fixing knob 9 provided on the side surface of the circular saw part holder 7 presses the guide bar 6 to fix the slide position of the circular saw part holder 7. A cutting portion (round saw portion) 11 is pivotally supported by the circular saw portion holder 7 via a shaft (oscillating shaft) 10. The cutting part 11 can swing up and down with respect to the upper surfaces of the base 1 and the turntable 2 by supporting the shaft 10. Between the circular saw part holder 7 and the cutting part 11, a spring 12 for biasing the cutting part 11 upward is provided. Although not shown, the lower limit position of the swing of the cutting portion 11 is determined by the stopper bolt supported by the cutting portion 11 coming into contact with the stopper receiving portion provided in the circular saw portion holder 7.

  The front surface of the holder 5 is provided with stoppers 5d and 5e that serve as positioning members during tilting. Stopper bolts 20 and 21 that are angle adjusting members are screwed in the vertical direction behind the upper surface of the turntable 2 so as to be positioned on the movement locus of the stoppers 5d and 5e. When the holder 5 is tilted, the stoppers 5d and 5e are engaged with the heads of the stopper bolts 20 and 21 at a predetermined tilt angle, and the tilt position of the cutting portion 11 is set. The stopper bolt 20 is provided so as to be engaged with the stopper 5d when the holder 5 is inclined to the position of 45 degrees to the left. Further, the stopper bolt 21 is provided so as to engage with the stopper 5e when the holder 5 is inclined to the position of 45 degrees in the right direction. Further, the above-described through hole 2a is provided in the upper part of the turntable 2, and a right-angle positioning pin 22 serving as a positioning member at a right angle is pivotally supported so as to be horizontally movable back and forth. Further, a stopper bolt 23 is screwed to the holder 5 in the vertical direction so as to be positioned on the movement locus of the right-angle positioning pin 22. When the holder 5 is in a right angle cutting position (a position where the side surface of the circular saw blade 18 is perpendicular to the turntable 2), the tip of the stopper bolt 23 and the outer diameter portion of the right angle positioning pin 22 come into contact with each other.

  A circular saw blade 18 is rotatably supported on the saw blade shaft of the cutting portion 11 by a bolt 25 and a flange 27. The cutting unit 11 is connected to a motor unit 16 for generating power, and a handle 19 having a switch (trigger switch) 31 is provided. A discharge port 13 to which a hose of a dust collector can be connected is provided at the rear part of the cutting unit 11, and chips and the like generated by the cutting operation can be discharged. The cutting unit 11 includes a saw cover 11 b that covers the upper outer periphery of the circular saw blade 18, and a protective cover 28 and a sub cover 40 that cover the lower outer periphery of the circular saw blade 18.

  The sub cover 40 is pivotally supported by a sub cover support pin (shaft) 41 at a position behind the circular saw blade 18 in the saw cover 11 b and covers the rear lower outer periphery of the circular saw blade 18. Note that “covering” means that the outer periphery of the rear lower portion of the circular saw blade 18 is hidden by the sub cover 40 in a side view shown in FIG. As shown in FIG. 4, the sub-cover 40 is divided into both sides of the plane where the circular saw blade 18 exists and covers the outer periphery of the rear lower portion of the circular saw blade 18.

  The sub cover 40 is urged clockwise (toward the base portion) about the axis of the sub cover support pin 41 by a spring 42 as an urging means, and the abutting portion 40a comes into contact with the saw cover 11b. Thus, rearward rotation is restricted (the lower rotation limit position with respect to the saw cover 11b is determined). The sub cover 40 is located between the protective cover 28 and the rear portion of the saw cover 11b, and when the cutting portion 11 is in the swing upper limit position (the swing position farthest from the base portion), the outer periphery of the sub cover 40 and the protective cover 28. Part of each other.

  A hinge arm 43 is fixed to the circular saw part holder 7 by screwing or the like. The hinge arm 43 extends from the circular saw part holder 7 toward the saw blade shaft side, and an arm pin 44 as an engaging member that can engage with the sub cover 40 is provided at the tip of the hinge arm 43. The arm pin 44 passes through the long hole 11 c provided in the saw cover 11 b and extends substantially parallel to the saw blade shaft, and is positioned on the rotation range of the sub cover 40.

  The protective cover 28 is provided on the outer periphery of the saw blade shaft so as to be rotatable around the saw blade shaft inside the saw cover 11b, and covers the saw blade rotation direction 18a (clockwise direction), that is, the circular saw blade 18 by a spring (not shown). Is biased in the direction. Further, the protective cover 28 rotates counterclockwise when the cutting part 11 swings downward (base part side), specifically, so as to rotate around the saw blade axis in conjunction with the swinging of the cutting part 11. It is engaged with the saw cover 11b by a link mechanism such as a link (not shown) so as to rotate in a direction (direction in which the circular saw blade 18 is exposed). In addition, since the engagement structure of the protective cover 28 and the saw cover 11b by a link mechanism may be the same as the past, description is abbreviate | omitted here.

  When the workpiece 35 is cut, depending on the height of the workpiece 35, the protective cover 28 rotated by the link mechanism in the process of the cutting portion 11 swinging to the lower limit position is attached to the workpiece 35. It rotates counterclockwise while abutting and rotating. In addition, when the cutting portion 11 swings downward from the upper limit position shown in FIG. 4 to the position shown in FIG. 6, the sub cover 40 has no overlap with the protective cover 28 (the engagement with the protective cover 28 is released). ), Which can be rotated in the counterclockwise direction (the direction away from the base portion) and rotated in the counterclockwise direction with respect to the saw cover 11b (relative movement) while being in contact with the workpiece 35 in the same manner as the protective cover 28. To do.

  In the above configuration, in order to set the cutting portion 11 to the vertical position and cut the workpiece 35 at a right angle, when the holder 5 is at the right angle cutting position, the right angle positioning pin 22 is moved forward and a stopper which is an inclination adjusting member. The position of the bolt 23 and the outer diameter portion of the right-angle positioning pin 22 are brought into contact with each other, and the clamp lever 30 is tightened to fix the inclined position of the holder 5. When the handle 19 is grasped and the switch 31 provided on the handle 19 is pulled, the motor unit 16 is driven to rotate, and the rotation of the motor unit 16 is rotated via a rotation transmission mechanism such as a belt and a gear (not shown) and a saw blade shaft. 18 and the circular saw blade 18 rotates. In this state, the handle 19 is pushed down against the urging force of the spring 12, the cutting part 11 is swung to the lower limit position, and the workpiece 35 is cut.

  After the cutting of the workpiece 35 is completed, if the force pushed down by the handle 19 is weakened, the cutting portion 11 is pushed upward by the spring 12 and returns to the original upper limit position. In the process where the cutting part 11 returns to the original position, the sub cover 40 and the protective cover 28 also return to the original position by their own weight and the respective springs.

  When the cutting portion 11 is in a first swinging range described later including the upper limit position, even if the sub-cover 40 is pressed from below (force to rotate away from the base portion), it is protected. At the overlapping portion of the cover 28 and the sub-cover 40, the sub-cover 40 abuts (engages) the outer periphery of the protective cover, and the rotation of the sub-cover 40 upward (in the direction away from the base portion) is restricted. Exposure of the circular saw blade 18 is prevented. In this way, the first swing range in which the rotation of the sub cover 40 is restricted by the engagement with the protective cover 28 is as follows. The cutting portion 11 swings downward from the upper limit position shown in FIG. As shown in the figure, the swing range is until the protective cover 28 rotated by the link mechanism and the sub cover 40 are not overlapped (until the engagement between the protective cover 28 and the sub cover 40 is released). When the cutting part 11 swings to the base part side (downward) beyond the first swinging range, the sub cover 40 does not engage with the protective cover 28.

  When the cutting portion 11 is in a second swinging range described later that swings further downward from the position of FIG. 6, the sub cover 40 rotates counterclockwise around the sub cover support pin 41 in relation to the protective cover 28. However, this time, the arm pin 44 restricts the counterclockwise rotation as shown in FIG. For this reason, when the cutting portion 11 is in the second swing range where the sub cover 40 does not engage with the protective cover 28, the force (from the base portion) tries to rotate the sub cover 40 counterclockwise. Even if the force to rotate in the direction away is inadvertently applied, the arm pin 44 restricts the rotation in the direction away from the base portion of the sub-cover 40 and suppresses the exposure of the circular saw blade 18 as much as possible. Can do. As described above, the second swing range in which the rotation of the sub cover 40 is restricted by the engagement with the arm pin 44 is such that the cutting portion 11 is located below the swing position where the sub cover 40 does not engage with the protective cover 28. The swing range is up to the front (FIG. 8) before the sub cover 40 comes into contact with the workpiece having the maximum height that can be cut by the tabletop cutting machine. At the lower swing position (range from the swing position shown in FIG. 8 to the swing lower limit position), the engagement relationship between the arm pin 44 and the sub cover 40 is lost, and the sub-work material 35 is cut when the workpiece 35 is cut. The cover 40 abuts on the workpiece 35 and can be rotated counterclockwise.

  In the process in which the cutting part 11 is returned from the lower limit position to the upper limit position by the spring 12, the sub cover 40 is protected by the spring 42 and its own weight before the swing position (FIG. 6) where the protective cover 28 and the sub cover 40 start to overlap. The cover 28 is returned to the original position (position where the abutting portion 40a contacts the saw cover 11b) before the cover 28, and then the protective cover 28 enters the sub cover 40 and returns to the initial state shown in FIG.

  If a malfunction of the sub-cover 40 occurs due to adhesion of chips or wood edges during or after cutting, the sub-cover 40 comes into contact with the arm pin 44 while the cutting part 11 returns to the upper limit position, and the protective cover 28 Before the swing position (FIG. 6) where the sub-cover 40 starts to overlap, the sub-cover 40 is forcibly rotated outward from the outer periphery of the protective cover 28 by the arm pin 44, and is almost at its original position (the abutting portion 40a). Is returned to the position where the saw cover 11b comes into contact), and at the upper limit position, the sub cover 40 covers the lower outer periphery of the circular saw blade 18 and the initial state shown in FIG. That is, when the arm pin 44 swings the cutting part 11 away from the base part (upward), the sub cover 40 covers the lower outer periphery of the circular saw blade 18 depending on its own weight and the biasing force of the spring 42. When it cannot return to the initial position, it abuts on the sub cover 40 and returns the sub cover 40 to the initial position.

  When performing angle cutting, the turntable 2 may be rotated to a desired angle and the workpiece 35 may be cut by the cutting method described above. When performing inclined cutting, the clamp lever 30 is loosened to release the fixed state of the holder 5, and the holder 5 is inclined leftward or rightward. In the case of the inclination to the left, the stopper 5d comes into contact with the stopper bolt 20, and the cutting part 11 is positioned in a state of 45 degrees to the left. In this state, the clamp lever 30 is tightened to fix the inclined position of the holder 5. After that, the work 35 may be cut by the cutting method described above.

  In any of the right angle cutting, the angle cutting, and the inclined cutting, when performing the slide cutting for cutting the wide workpiece, the wide workpiece 35a is provided on the front surface of the fence 3 as shown in FIG. After the pressing and fixing, the slide position fixing knob 9 shown in FIG. 2 is loosened, and the handle 19 is pulled forward. Then, the circular saw holder 7 and the cutting part 11 are integrally slid forward along the guide bar 6. Moving. Then, the handle 19 is pushed down to the swinging lower limit position of the cutting portion 11 to cut the workpiece 35a, and then the slide cutting is performed while the cutting portion 11 is slid rearward. Although depending on the height of the workpiece 35a, as shown in FIG. 10, also in the slide cutting, the protective cover 28 and the sub cover 40 are cut while contacting the workpiece 35a. If the force that pushed down the handle 19 is weakened after cutting, the cutting portion 11 is pushed upward by the spring 12, and the protective cover 28 is pressed by a spring (not shown) biased in the saw blade rotation direction 18a. Return to state 1. In this way, right-angle cutting, angle cutting, tilt cutting, slide cutting, and combined cutting combining angle cutting and tilt cutting are possible.

  FIG. 11 is an enlarged side view of the cutting part 11 when the sub cover 40 becomes defective in the desktop cutting machine of the comparative example. The tabletop cutting machine of this comparative example is different from that of the embodiment in that the hinge arm 43, the arm pin 44, and the long hole 11c through which the arm pin 44 passes are eliminated, and the other points are the same. The swinging position of the cutting part 11 shown in FIG. 11 is the same as that of FIG. 7, but in FIG. However, unlike FIG. 7, the lower outer periphery of the circular saw blade 18 is not covered.

  According to the present embodiment, the following effects can be achieved.

(1) When the rotation of the sub cover 40 with respect to the saw cover 11b is hindered by chips or the like when the cutting portion 11 is swung away from the base portion, the arm pin 44 comes into contact with the sub cover 40 to Since the cover 40 is returned to the initial position covering the lower outer periphery of the circular saw blade 18, unlike the structure of the comparative example, the risk that the sub cover 40 cannot cover the lower outer periphery of the circular saw blade 18 even if the cutting portion 11 is returned to the upper limit position. Can be reduced. That is, when the cutting part 11 is swung away from the base part (when the cutting part 11 is returned to the upper limit position), the sub cover 40 can be reliably returned to the initial position.

(2) When a force is applied to rotate the sub cover 40 counterclockwise when the cutting portion 11 is within the first swing range including the upper limit position, the protective cover 28 is Since the rotation of the sub cover 40 in the direction away from the base portion by engaging with the cover 40 is restricted, inadvertent exposure of the circular saw blade 18 can be suppressed.

(3) When the cutting portion 11 is within the second swing range described above where the sub cover 40 does not engage the protective cover 28, a force is applied to rotate the sub cover 40 counterclockwise. Since the arm pin 44 restricts the rotation of the sub cover 40 in the direction away from the base portion, inadvertent exposure of the circular saw blade 18 can be suppressed.

  The present invention has been described above by taking the embodiment as an example. However, it is understood by those skilled in the art that various modifications can be made to each component and each processing process of the embodiment within the scope of the claims. By the way. Hereinafter, modifications will be described.

  The relative movement of the sub cover 40 with respect to the saw cover 11b is not limited to the rotation exemplified in the embodiment, and may be other relative movement such as a slide. The spring 42 that urges the sub cover 40 toward the base portion may be omitted. In this case, since the urging force by the spring 42 is lost, malfunction of the sub cover 40 is likely to occur. However, when the cutting portion 11 is swung away from the base portion, the sub cover 40 returns to the initial position under its own weight. If this is not possible, the arm pins 44 come into contact with the sub-cover 40 to return the sub-cover 40 to the initial position, so that the sub-cover 40 can be reliably returned to the initial position as in the embodiment.

  In the embodiment, the guide bar 6 is fixed to the holder 5 and the circular saw part holder 7 and the cutting part 11 are slid along the guide bar 6 as an example. However, the guide bar 6 has the circular saw part holder 7 and The structure which slides with respect to the holder 5 with the cutting part 11 may be sufficient. Further, the tabletop cutting machine may be of a non-sliding type (a type in which the cutting unit 11 does not slide with respect to the holder 5).

1 base, 2 turntable, 2a long hole, 3 fence, 4 holder shaft (tilting shaft), 5 holder, 5d, 5e stopper, 6 guide bar, 7 circular saw holder, 8 support, 9 slide position fixing knob, DESCRIPTION OF SYMBOLS 10 Shaft (oscillating shaft), 11 Cutting part (circular saw part), 11b Saw cover, 11c Elongated hole, 12 Spring, 13 Discharge port, 16 Motor part, 18 Circular saw blade (cutting blade), 18a Saw blade rotation direction, 19 Handle, 20, 21 Stopper bolt, 22 Right angle positioning pin, 23 Stopper bolt, 25 bolt, 27 Flange, 28 Protective cover, 30 Clamp lever, 31 Switch (trigger switch), 35, 35a Work material, 40 Sub cover, 40a Abutting portion, 41 Sub-cover support pin (shaft), 42 Spring, 43 Hinge arm, 44 Arm pin (engaging member)

Claims (13)

A base portion having a placement surface on which a workpiece can be placed;
A cutting part that rotatably supports the cutting blade;
A holder portion that swingably supports the cutting portion so as to be close to and away from the base portion;
The cutting portion includes a saw cover that covers an upper outer periphery of the cutting blade, a protective cover and a sub-cover that covers a lower outer periphery of the cutting blade,
The protective cover rotates around the rotation axis of the cutting blade in conjunction with the swinging of the cutting portion,
When the sub cover swings the cutting part toward the base part, the sub cover moves relative to the saw cover while contacting the workpiece on the mounting surface.
The holder part has an engaging member that can engage with the sub-cover;
The engaging member may come into contact with the sub cover to return the sub cover to an initial position covering the lower outer periphery of the cutting blade when the cutting portion is swung away from the base portion. A desktop cutting machine that can.   When the engaging member swings the cutting portion away from the base portion, the sub-cover is subject to its own weight, or the urging force that urges the own weight and itself toward the base portion side. 2. The tabletop cutting machine according to claim 1, wherein when it is not possible to return to the initial position, the tabletop cutting machine contacts the sub cover and returns the sub cover to the initial position.   When the relative movement of the sub-cover with respect to the saw cover is hindered when the engaging member swings the cutting portion away from the base portion, the engaging member contacts the sub-cover to The tabletop cutting machine according to claim 1, wherein the tabletop cutting machine is returned to the initial position.   When the sub-cover is in a first swing range separated from the base portion and a force is applied to the sub-cover to make a relative movement in a direction away from the base portion, The tabletop cutting machine according to any one of claims 1 to 3, wherein relative movement in a direction away from the base portion by being engaged with the protective cover is restricted.   5. The tabletop cutting machine according to claim 4, wherein the sub cover does not engage with the protective cover when the cutting portion swings toward the base portion beyond the first swing range.   When the cutting portion is within a second swing range that is a part of the swing range in which the sub cover does not engage the protective cover, the sub cover moves relative to the sub cover in a direction away from the base portion. The tabletop cutting machine according to any one of claims 1 to 5, wherein when a force to be applied is applied, relative movement of the sub cover in a direction away from the base portion is restricted by the engagement member. A base portion having a placement surface on which a workpiece can be placed;
A cutting part that rotatably supports the cutting blade;
A holder portion that swingably supports the cutting portion so as to be close to and away from the base portion;
The cutting portion includes a saw cover that covers an upper outer periphery of the cutting blade, a protective cover and a sub-cover that covers a lower outer periphery of the cutting blade,
The protective cover rotates around the rotation axis of the cutting blade in conjunction with the swinging of the cutting portion,
When the sub cover swings the cutting part toward the base part, the sub cover moves relative to the saw cover while contacting the workpiece on the mounting surface.
The holder part has an engaging member that can engage with the sub-cover;
When the cutting portion is within a second swing range that is a part of the swing range in which the sub cover does not engage the protective cover, the sub cover moves relative to the sub cover in a direction away from the base portion. When a force to be applied is applied, a tabletop cutting machine in which relative movement of the sub cover in a direction away from the base portion is restricted by the engagement member.   The second swing range is a swing in which the sub cover comes into contact with a workpiece having a maximum height that can be cut by the tabletop cutting machine from a swing position where the sub cover does not engage with the protective cover. The tabletop cutting machine according to claim 6 or 7, which is a range up to a position.   The tabletop cutting machine according to any one of claims 1 to 8, further comprising an urging unit that urges the sub cover toward the base portion.   The tabletop cutting machine according to any one of claims 1 to 9, wherein the sub cover is rotatably supported by the saw cover, and the relative movement is rotation.   The said holder part has a guide bar extended in parallel with the mounting surface as described above, The said cutting part is movable in the extension direction of the said guide bar by the support of the said guide bar. A tabletop cutting machine according to claim 1.   12. The holder according to claim 1, wherein the holder portion is connected to the base portion via an inclined shaft extending in parallel with the placement surface, and can be inclined with respect to the base portion using the inclined shaft as a fulcrum. The tabletop cutting machine according to one item.   The base portion includes a base and a turntable rotatably provided on the base via a rotation shaft orthogonal to the placement surface, and the holder portion is configured to turn the turn via the inclined shaft. The tabletop cutting machine of claim 12, connected to a table.

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