JP2012218082A - Power tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power tool capable of enhancing the action of a blade to a material to be ground by effectively utilizing a movement amount of reciprocal movement while suppressing vibration accompanied by the reciprocal movement.SOLUTION: One slider 9 to which a cutter 2 is attached and the other slider 10 as a counter weight perform reciprocal movement with reverse phases and thus vibration accompanied by reciprocal movement is suppressed. One slider 9 and the other slider 10 are disposed in positions separated in a direction orthogonal to movement directions and a rotational moment by the movement of the one slider 9 and the cutter 2 and a rotational moment by the movement of the other slider 10 are made to act toward the material to be ground during the movement in a direction in which the cutter 2 is made to act on the material to be ground in the reciprocal movement of one slider 9 and the cutter 2, and thus, the action of the cutter to the material to be ground is enhanced.

Description

  The present invention relates to an electric tool such as a reciprocating saw or a jigsaw provided with a reciprocating motion mechanism for converting a rotational motion by a driving source such as a motor into a reciprocating motion.

  As this type of electric tool, for example, one described in Patent Document 1 has been proposed. This is provided with a rotating sleeve that is rotated by a drive source such as a motor, and a pair of sliders are inserted and mounted in a rotation-restricted state on the rotating sleeve, and the rotating sleeve and each slider are integrated into one of them. The ball provided is connected to the other through an annular groove which is fitted to the other and which is inclined with respect to the axis of the rotating sleeve.

  According to this configuration, as the ball moves in the annular groove as the rotating sleeve rotates, one of the sliders inserted in the rotating sleeve reciprocates and is attached to the one slider accordingly. While the blade (saw) reciprocates, the other sleeve covered by the rotating sleeve reciprocates with one slider in the opposite phase. For this reason, the momentum of the one slider and the cutter and the momentum of the other slider as the counterweight cancel each other, thereby suppressing the vibration associated with the reciprocating motion of the one slider and the cutter.

JP 2000-291762 A

  In the electric power tool described in Patent Document 1, the pair of sliders reciprocate on the same axis of the cylindrical body, so that space saving can be achieved. However, the effect that such a power tool can achieve is limited to this.

  The present invention has been made in view of such circumstances, and an electric tool capable of enhancing the action of a blade on a work material by effectively utilizing the momentum of the reciprocating motion while suppressing vibrations associated with the reciprocating motion. It is an issue to provide.

  The present invention includes a rotating shaft that is rotated by a drive source and a pair of sliders that are provided in a rotation-restricted state, and the rotating shaft and each slider are provided on one of the balls, and the other is provided with a ball Are connected to each other via an annular groove inclined with respect to the axis of the rotary shaft, and the rotary shaft rotates, so that one slider to which the blade is attached and the other slider as the counterweight are reversed. In a power tool configured to reciprocate in phase, the rotational moment due to the movement of one slider and the blade and the rotational moment due to the movement of the other slider are subject to the blade being covered in the reciprocating motion of one slider and the blade. During movement in the direction that acts on the work material, one slider and the other slider are separated in a direction perpendicular to the direction of movement so as to act on the work material. Characterized in that it is arranged at a position.

  According to this configuration, one slider to which the blade is attached and the other slider as the counterweight reciprocate in opposite phases, so that the momentum of one slider and the blade and the momentum of the other slider cancel each other. Fit. Thereby, the vibration accompanying the reciprocating motion of one slider and a cutter can be suppressed.

  Further, one slider and the other slider are arranged at positions separated in a direction orthogonal to the direction of motion, and the rotational moment due to the motion of one slider and the blade and the rotational moment due to the motion of the other slider are: Of the reciprocating motion of one slider and the blade, during the movement in the direction in which the blade acts on the work material, by acting on the work material, when the blade acts on the work material, The effect of rotational moment is added. Thereby, the effect | action of the cutter with respect to a workpiece can be improved.

  Here, in the present invention, it is possible to adopt a configuration in which the blade is a saw, and one of the sliders is disposed on the work material side. According to this configuration, the rotational moment due to the movement of one slider and the blade and the rotational moment due to the movement of the other slider are directed toward the work material during the movement in the direction in which the blade pulls the work material. By acting, when the blade cuts the work material, the load of the blade on the cutting portion of the work material increases. As a result, the degree of engagement of the blade (the degree of biting) can be improved, and the machinability can be improved (the action of the blade on the work material can be enhanced).

  Further, in the present invention, the annular groove is formed on the outer periphery of the rotating shaft, and the ball provided on one slider and the ball provided on the other slider are arranged at opposite positions of the same annular groove, It is preferable to adopt a configuration in which the slider and the other slider are arranged at opposite positions with the rotation axis in between. According to such a configuration, one slider and the other slider can be reciprocated by one annular groove, the structure is simplified, the manufacturing cost can be reduced, and maintenance and repair are easy. Can be done.

  In the present invention, the annular groove may be configured so that the shape from one end to the other end in the axial direction of the rotating shaft and the shape from the other end to the one end are asymmetric. . According to this configuration, it is possible to increase the degree of freedom in designing the reciprocating motion of one slider and the other slider, and to pursue better cutting conditions.

  As described above, according to the present invention, the action of the blade on the work material can be enhanced by effectively utilizing the momentum of the reciprocating motion while suppressing the vibration associated with the reciprocating motion.

The side view containing the partial cross section of the reciprocating saw as an electric tool which concerns on this embodiment is shown. It is a principal part of the reciprocating saw, wherein (a) is a side view including a partial cross section, and (b) is a bottom view. It is a rotating shaft in the same reciprocating saw, (a) shows a top view, (b) shows a side view. It is a side view containing the partial cross section of the principal part of the same reciprocating saw, (a) shows the state where the saw blade was pushed, (b) shows the state where the saw blade was pulled. 5 is a graph showing the profile of the annular groove formed on the outer periphery of the rotating shaft in the reciprocating saw, that is, the relationship between the rotation angle of the rotating shaft and the stroke amount of the saw blade (the displacement amount of the annular groove in the axial direction of the rotating shaft). (A) and (d) are patterns in which the shape from one end to the other end of the annular groove in the axial direction of the rotation axis is symmetrical to the shape from the other end to one end, (b) and (c) Indicates an asymmetric pattern. The side view containing the partial cross section of the reciprocating saw which concerns on other embodiment is shown.

  Hereinafter, a reciprocating saw as a cutting tool will be described in detail with reference to the drawings as an embodiment of an electric tool according to the present invention.

  The reciprocating saw according to the present embodiment includes a main body 1 extending in one direction and a saw blade as a cutter attached to the tip of the main body 1 and reciprocating along the direction in which the main body 1 extends as shown in FIG. 2 is provided. The main body 1 is roughly composed of a base end portion 1a, an intermediate portion 1b connected to the base end portion 1a, and a tip end portion 1c connected to the intermediate portion 1b.

  The base end 1 a accommodates the main body 3 a of the motor 3. More specifically, the base end 1a accommodates the main body 3a of the motor 3 so that the axis of the drive shaft 3b of the motor 3 is arranged along the direction in which the main body 1 extends. Further, a power cord 4 extends from the base end 1a, and the motor 3 is driven by receiving power supply from a power source (household power source or industrial power source) via the power cord 4.

  The intermediate part 1b accommodates the drive shaft 3b of the motor 3 and the intermediate shaft 5 connected to the drive shaft 3b. More specifically, the intermediate portion 1b accommodates the drive shaft 3b of the motor 3 so that the axis of the drive shaft 3b of the motor 3 is arranged along the direction in which the main body portion 1 extends, and the axis of the intermediate shaft 5 However, the intermediate shaft 5 is accommodated so as to be arranged along the direction in which the main body 1 extends. The intermediate shaft 5 is disposed such that its axis coincides with the axis of the drive shaft 3 b of the motor 3. That is, the intermediate shaft 5 rotates coaxially with the drive shaft 3 b of the motor 3.

  The intermediate part 1b also serves as a grip part when the operator holds the main body part 1. For this reason, the outer shape of the intermediate portion 1b is ergonomically easy to grip. A switch 6 is provided at the tip of the intermediate portion 1b. In the switch 6, the operator grips the main body 1 (intermediate portion 1b) so that the blade of the saw blade 2 faces downward (so that the blade of the saw blade 2 moves away from the worker). At this time, the switch 6 is provided on the operator's fingertip so as to be directed downward (the direction toward the blade side of the saw blade 2) of the main body portion 1 (intermediate portion 1b).

  The tip portion 1 c accommodates the reciprocating mechanism 7. As shown in FIG. 2, the reciprocating mechanism 7 includes a rotary shaft 8 connected to the intermediate shaft 5, a first slider 9 provided in a rotation restricted state, and a second slider 10 provided in the same rotation restricted state. Is provided. More specifically, the tip 1c accommodates the rotary shaft 8 so that the axis of the rotary shaft 8 is arranged along the direction in which the main body 1 extends, and the axis of the first slider 9 is The first slider 9 is accommodated so as to be disposed along the direction in which the main body 1 extends, and the second slider 10 is accommodated so that the axis of the second slider 10 is disposed along the direction in which the main body 1 extends. . The rotating shaft 8 is arranged such that its axis line coincides with the axis line of the drive shaft 3 b of the motor 3 (and the axis line of the intermediate shaft 5). That is, the rotary shaft 8 rotates coaxially with the drive shaft 3b (and the intermediate shaft 5) of the motor 3.

  The first slider 9 and the second slider 10 are both block-shaped, and are arranged at positions spaced apart (in parallel) in a direction perpendicular to the direction in which the main body 1 extends (that is, the direction in which the saw blade 2 reciprocates). Is done. More specifically, the first slider 9 and the second slider 10 are disposed at opposite positions with the rotation shaft 8 in between. Preferably, the first slider 9 and the second slider 10 are arranged at symmetrical positions around the rotation axis 8. More specifically, with respect to the rotating shaft 8, the first slider 9 is disposed closer to the work material, and the second slider 10 is disposed farther from the work material.

  On one surface of the first slider 9 (the surface on the rotating shaft 8 side), the ball 11 is disposed in a recess that is recessed in a substantially hemispherical shape. The ball 12 is also disposed in a concave portion that is formed in a substantially hemispherical shape on one surface of the second slider 10 (the surface on the rotating shaft 8 side). On the other hand, an annular groove 8a is formed on the outer periphery of the rotating shaft 8 (see FIG. 3). Then, when the balls 11 and 12 are fitted into the annular groove 8a, the rotary shaft 8 and the sliders 9 and 10 are operatively connected.

  The annular groove 8 a is formed so as to be inclined with respect to the axis of the rotary shaft 8. More specifically, the annular groove 8a has one end of the annular groove 8a in the axial direction of the rotating shaft 8 (the point where the tangent to the annular groove 8a is perpendicular to the axial direction of the rotating shaft 8; The shape from the other end (another point where the tangent of the annular groove 8a is perpendicular to the axial direction of the rotary shaft 8, hereinafter referred to as “bottom dead center” for convenience). And a profile in which the shape from the other end to the one end is symmetric (see FIG. 5A). Therefore, the ball 11 and the ball 12 are disposed at positions opposite to the annular groove 8a.

  A through hole is formed in the first slider 9 along the axial direction, and the shaft portion 13a of the blade attachment member 13 is inserted therethrough. For example, the first slider 9 is fixed to the shaft portion 13 a of the blade attachment member 13 by tightening a screw (not shown) that is screwed into the first slider 9. The shaft portion 13a of the blade mounting member 13 is slidably supported by bearings (metal bushes) 14 and 15 that are inserted and fixed to the tip portion 1c at two spaced apart positions. That is, the shaft portion 13a of the blade attachment member 13 is connected to the main body portion 1 (the front end portion 1c) via a pair of bearings 14 and 15 disposed at spaced positions in the main body portion 1 (the front end portion 1c). Supported slidably. Therefore, when the ball 11 moves in the annular groove 8a as the rotary shaft 8 rotates, the first slider 9 and the blade attachment member 13 integrated with the first slider 9 are extended in the direction in which the main body 1 extends. Reciprocate along.

  The shaft portion 13a of the blade attachment member 13 has a length such that the tip side protrudes from the tip portion 1c. More specifically, the blade mounting member 16 is attached in a state where the retaining bush 16 is attached to the distal end of the distal end portion 1c and the shaft portion 13a of the blade mounting member 13 is inserted into the insertion hole formed in the retaining bush 16. The front end side of the 13 shaft portions 13a protrudes from the front end portion 1c. The protruding amount of the shaft portion 13a of the blade attachment member 13 is minimized at the position where the first slider 9 is most pulled, that is, the position where the first slider 9 is farthest from the tip of the tip portion 1c.

  A fixture 13 b is attached to the tip of the shaft portion 13 a of the blade attachment member 13. The fixture 13b includes a slit (not shown) for inserting the root portion of the saw blade 2, and a fixing screw for fixing the saw blade 2 in a state where the root portion of the saw blade 2 is inserted into the slit. 13c. The fixture 13b is formed flat in the width direction so that the width size does not increase (see FIG. 2B).

  A through hole is formed in the second slider 10 along its axial direction, and a bearing (metal bush) 17 is mounted in the through hole. The guide shaft 18 for the second slider 10 is inserted into the bearing 17 and is inserted into the distal end portion 1c so that both ends are supported and fixed by elements in the distal end portion 1c. Accordingly, when the ball 12 moves in the annular groove 8a as the rotary shaft 8 rotates, the second slider 10 reciprocates along the guide shaft 18 (that is, along the direction in which the main body 1 extends). To do. In addition, as described above, since the ball 11 of the first slider 9 and the ball 12 of the second slider 10 are disposed at positions opposite to the annular groove 8a, the second slider 10 reciprocates in the opposite phase to the first slider 9. Exercise.

  A speed reduction unit 19 is provided between the intermediate shaft 5 and the rotary shaft 8. For this reason, the rotating shaft 8 rotates at a lower speed than the drive shaft 3 b of the motor 3. Thereby, the saw blade 2 detachably attached to the first slider 9 and the second slider 10 and the first slider 9 (via the blade attachment member 13) can be reciprocated at a desired speed. The speed reduction part 19 is composed of a plurality of planetary gears 19a,... Arranged around the axis of the intermediate shaft 5. The planetary gears 19a, ... are housing parts 8b formed at the base end of the rotary shaft 8 (see FIG. 3). ).

  Incidentally, the configuration of the reference numeral 20 is a guard bar of the saw blade 2 that is attached to the distal end of the distal end portion 1 c of the main body 1, more precisely, the retaining bush 16. The configuration of reference numeral 21 is for rotatably supporting the rotating shaft 8 (the distal end and the proximal end thereof) in the main body portion 1 (the distal end portion 1c) and restricting the movement of the rotating shaft 8 in the axial direction. It is a bearing. The structure of the code | symbol 22 is a bearing (bearing) for supporting the intermediate shaft 5 (front-end | tip) rotatably within the main-body part 1 (front-end | tip part 1c). The configuration of reference numeral 23 is for rotatably supporting the drive shaft 3b of the motor 3 in the main body portion 1 (the base end portion 1a or the intermediate portion 1b thereof) and restricting the movement of the rotary shaft 8 in the axial direction. This is a bearing.

  As described above, according to the reciprocating saw according to the present embodiment, the first slider 9, the blade attachment member 13 and the saw blade 2 move forward while the rotary shaft 8 is rotated halfway (0 to 180 degrees). The second slider 10 commensurate with these momentums moves in the opposite direction. Moreover, while the rotating shaft 8 makes another half rotation (180-360 degree rotation), while the 1st slider 9, the blade attachment member 13, and the saw blade 2 return, the 2nd slider 10 returns in the opposite direction. . That is, the first slider 9 to which the saw blade 2 is attached (via the blade attachment member 13) and the second slider 10 as the counterweight reciprocate in opposite phases, whereby the first slider 9 (the blade attachment) The momentum of the member 13) and the saw blade 2 and the momentum of the second slider 10 cancel each other. For this reason, according to the reciprocating saw according to the present embodiment, it is possible to suppress vibration associated with the reciprocating motion of the first slider 9 (and the blade attachment member 13) and the saw blade 2.

  Further, according to the reciprocating saw according to the present embodiment, as shown in FIG. 4, the first slider 9 is disposed closer to the work material X, and the second slider 10 is disposed farther from the work material X. Therefore, during the movement in the direction in which the saw blade 2 acts on the workpiece X, that is, during the movement in the direction in which the saw blade 2 pulls the workpiece X (from FIG. 4A to FIG. 4B). In the process of transition), the rotational moment M1 due to the movement of the first slider 9 (and the blade mounting member 13) and the saw blade 2 located on the distal end side of the main body 1 relative to the second slider 10 and the first slider 9 A combined rotational moment M3 with the rotational moment M2 due to the movement of the second slider 10 located on the base end side of the main body 1 acts toward the work material X. That is, when the saw blade 2 cuts the work material X, the load of the saw blade 2 on the cutting portion of the work material X increases. For this reason, according to the reciprocating saw according to the present embodiment, the amount of engagement (the degree of biting) of the saw blade 2 can be improved by effectively utilizing the momentum (rotational moments M1, M2) of the reciprocating motion in the form of the combined rotational moment M3. Thus, the machinability can be improved.

  When the saw blade 2 cuts the work material X, the load of the saw blade 2 on the cutting portion of the work material X increases, so that the operator loosens the force for pressing the saw blade 2 against the work material X. It is possible to reduce worker fatigue.

  Further, according to the reciprocating saw according to the present embodiment, the first slider 9 is disposed closer to the work material X, and the second slider 10 is disposed farther from the work material X. During the movement in the direction opposite to the direction in which the workpiece X is applied, that is, during the movement in the direction in which the saw blade 2 is returned to the state before the workpiece X is pulled (FIG. 4B to FIG. 4). (The process of shifting to (a)), the rotational moment M1 ′ due to the movement of the first slider 9 (and the blade mounting member 13) and the saw blade 2 located on the base end side of the main body 1 relative to the second slider 10, and A combined rotational moment M3 ′ with a rotational moment M2 ′ due to the movement of the second slider 10 located on the distal end side of the main body 1 relative to the first slider 9 acts in a direction away from the work material X. That is, when the saw blade 2 is returned to the state before cutting the work material X, the load of the saw blade 2 on the cutting portion of the work material X is greatly reduced or eliminated. For this reason, according to the reciprocating saw according to the present embodiment, the kickback to the worker (a phenomenon in which the saw blade 2 is caught by the work material X and the saw blade 2 rebounds to the worker side by the reaction force) is reduced. Or it can be eliminated.

  When the saw blade 2 is returned to the state before the work material X is pulled, the load on the motor 3 is reduced because the load of the saw blade 2 on the cutting portion of the work material X is greatly reduced or eliminated. , Can reduce power consumption.

  Further, according to the reciprocating saw according to the present embodiment, the ball 11 provided on the first slider 9 and the ball 12 provided on the second slider 10 are arranged at positions opposite to the same annular groove 8a, so that the first Since the slider 9 and the second slider 10 are disposed at opposite positions with the rotary shaft 8 in between, the first slider 9 and the second slider 10 can be reciprocated by the single annular groove 8, and the structure is simple. become. For this reason, according to the reciprocating saw according to the present embodiment, the manufacturing cost can be reduced, and maintenance and repair can be easily performed.

  Moreover, according to the reciprocating saw according to the present embodiment, the first slider 9, the rotating shaft 8, and the second slider 10 are arranged on a surface along a direction orthogonal to the direction in which the saw blade 2 reciprocates. Therefore, as is clear from FIG. 2B, the width of the tip 1c is small and is formed flat in the width direction. For this reason, for example, there is a wall in the vicinity of the cutting portion of the work material (the cutting portion of the work material is located near the wall), and the work material can be smoothed even in an environment where the tip 1c hits the wall. Can be cut. On the other hand, in the case of the electric power tool described in Patent Document 1, since the pair of sliders are inserted and packaged in the rotation restricted state on the rotating sleeve, the width size of the tip portion is increased. For this reason, there is a problem that the tip part hits the wall and gets in the way, and unless the saw blade 2 is bent greatly, the work material near the wall cannot be cut, and the cutting operation does not proceed smoothly.

  In addition, this invention is not limited to the said embodiment, A various change is possible in the range which does not deviate from the summary of this invention.

  For example, in the embodiment described above, since a saw is used, the first slider 9 is disposed closer to the work material X, and the second slider 10 is disposed farther from the work material X. Since one slider 9 is disposed farther from the work material X and the second slider 10 is disposed closer to the work material X, a push saw can be employed.

  Moreover, in the said embodiment, although the 1st slider 9 and the 2nd slider 10 are reciprocatingly moved in the opposite phase by the one annular groove 8, each for 1st slider 9 and 2nd slider 10 is used. Separate annular grooves may be formed on the outer periphery of the rotary shaft 8. According to such a configuration, the reciprocating motion of the first slider 9 (the reciprocating motion of the blade) and the reciprocating motion of the second slider 10 can be designed separately (independently), and the degree of design freedom can be increased. Can be increased. However, the first slider 9 and the second slider 10 are reciprocated by one annular groove 8 because the structure is complicated, high part accuracy is required, the manufacturing cost is increased, and maintenance and repair are complicated. A configuration that exercises is preferred.

  Moreover, in the said embodiment, as shown to Fig.5 (a), as a shape of the annular groove 8a, the shape from a top dead center to a bottom dead center and the shape from a bottom dead center to a top dead center become symmetrical. Although a profile is adopted, as shown in FIG. 5B, a profile in which the top dead center is shifted from the position opposite to the bottom dead center (180 degree position) to one side may be used. According to this configuration, the movement in the direction opposite to the direction in which the saw blade 2 acts on the work material, that is, the movement in the direction in which the saw blade 2 is returned to the state before the work material is pulled (FIG. 4). In the process of shifting from (b) to FIG. 4 (a): at the time of push-off, the movement time is shorter than in the standard pattern of FIG. 5 (a), so the movement speed becomes faster and the movement in the opposite direction ( In the process of shifting from FIG. 4 (a) to FIG. 4 (b): at the time of drawing, the movement time is longer than that of the standard pattern of FIG. For this reason, the scraping property at the time of drawing is good. Moreover, in the case of light cutting, the cutting performance at the time of push cutting is high. In the case of heavy cutting, although the speed at the time of cutting is slower than that of the standard pattern, the cutting performance is high because the torque is high.

  Conversely, as shown in FIG. 5C, the profile may be such that the top dead center is shifted from the position opposite to the bottom dead center (180 degree position) to the other side. According to this configuration, the movement in the direction in which the saw blade 2 acts on the work material, that is, the movement in the direction in which the saw blade 2 pulls the work material (from FIG. 4A to FIG. 4B). In the process of transition: at the time of drawing, since the movement time is shorter than the standard pattern of FIG. 5A, the movement speed is increased, and the movement in the opposite direction (from FIG. 4B to FIG. In the process of shifting to a): at the time of push-off, the movement time becomes longer compared to the standard pattern in FIG. For this reason, in the case of light cutting, the cutting performance at the time of cutting is high. In the case of heavy cutting, although the speed at the time of press cutting is slower than that of the standard pattern, the cutting performance is high because the torque is high.

  In the reciprocating saw according to the present embodiment, the saw blade 2 can be reciprocated by rotating the motor 3 forward, or the saw blade 2 can be reciprocated by reversing the motor 3. Therefore, the profile in FIG. 5C is the same as the profile in FIG. 5B when the motor 3 is reversed.

  Alternatively, as shown in FIG. 5D, a profile in which the rate of change of the stroke amount with respect to the rotation angle of the rotary shaft 8 is increased may be used. According to this configuration, the movement in the direction in which the saw blade 2 acts on the work material, that is, the movement in the direction in which the saw blade 2 pulls the work material (from FIG. 4A to FIG. 4B). Transition process: during pulling) and movement in the opposite direction (transition process from FIG. 4 (b) to FIG. 4 (a): during push-off) move compared to the standard pattern of FIG. 5 (a). Since the time is shortened, the moving speed is increased. For this reason, in the case of light cutting, cutting performance is high. Also, since the moving speed is sufficiently reduced before and after the top dead center and the bottom dead center (movement direction turning point), the annular groove is received from the ball at the top dead center and the bottom dead center (movement direction turning point). Impact is reduced and durability is improved.

  Moreover, in the said embodiment, as shown to Fig.5 (a), as the shape of the annular groove 8a, the shape from a top dead center to a bottom dead center, and the shape from a bottom dead center to a top dead center are point-symmetric, respectively. The absolute value of acceleration when accelerating and the absolute value of acceleration when decelerating are the same value, but the acceleration during acceleration (absolute value) is the acceleration during deceleration ( Or an acceleration (absolute value) during deceleration may be greater than an acceleration (absolute value) during acceleration.

  In the above embodiment, both ends of the guide shaft 18 that guides the second slider 10 are supported and fixed by the elements in the tip 1c. However, the guide shaft 18 is not fixed and the first shaft 18 is fixed. Similarly to the relationship between the slider 10 and the shaft portion 13 a of the blade attachment member 13, the guide shaft 18 may be fixed to the second slider 10, and the guide shaft 18 may reciprocate together with the second slider 10.

  Moreover, in the said embodiment, although the deceleration part 19 is arrange | positioned between the intermediate shaft 5 and the rotating shaft 8, as shown in FIG. 6, the base end side part 8c equivalent to the intermediate shaft 5 of FIG. A rotating shaft 8 in which a tip end side portion 8 d corresponding to one rotating shaft 8 is integrated may be adopted, and a speed reducing portion 19 may be disposed between the drive shaft 3 b of the motor 3 and the rotating shaft 8. . According to such a configuration, since the planetary gears 19a,... Are arranged around the shaft, the speed reduction portion 19 that inevitably increases in width size is further away from the tip portion 1c of the main body portion 1, and thus the flatness of the tip portion 1c The shape is further extended, and accordingly, the cutting work of the work material near the wall can be performed more smoothly.

  DESCRIPTION OF SYMBOLS 1 ... Main-body part, 1a ... Base end part, 1b ... Intermediate | middle part, 1c ... Tip part, 2 ... Saw blade (blade), 3 ... Motor (drive source), 3a ... Main-body part, 3b ... Drive shaft, 4 ... Power supply Code 5 ... Intermediate shaft 6 ... Switch 7 ... Reciprocating motion mechanism 8 ... Rotating shaft 8a ... Annular groove 8b ... Housing part 8c ... Base end side part 8d ... Tip side part 9 ... First slider (One slider), 10 ... second slider (the other slider), 11, 12 ... ball, 13 ... blade mounting member, 13a ... shaft, 13b ... mounting tool, 13c ... fixing screw, 14, 15 ... bearing, DESCRIPTION OF SYMBOLS 16 ... Retaining prevention bush, 17 ... Bearing, 18 ... Guide shaft, 19 ... Deceleration part, 19a ... Planetary gear, 20 ... Guard bar, 21-23 ... Bearing

Claims (4)

  A rotation shaft rotated by a drive source and a pair of sliders provided in a rotation-restricted state are provided, and the rotation shaft and each slider are provided in one of the balls, and the other is provided in the ball. The slider is connected via an annular groove that is inclined with respect to the axis of the rotary shaft, and when the rotary shaft rotates, one slider to which the blade is attached and the other slider as the counterweight reciprocate in opposite phases. In a power tool configured to perform the rotation moment due to the movement of one slider and the blade and the rotation moment due to the movement of the other slider, the blade acts on the work material out of the reciprocating movement of the one slider and the blade. The position where one slider and the other slider are separated in a direction perpendicular to the direction of movement so that they act toward the work material during movement in the direction of movement Power tool characterized in that it is arranged.   The power tool according to claim 1, wherein the blade is a draw saw, and is arranged so that one slider is on a workpiece side.   An annular groove is formed on the outer periphery of the rotating shaft, and the ball provided on one slider and the ball provided on the other slider are arranged at opposite positions of the same annular groove, so that one slider and the other slider The power tool according to claim 1, wherein the power tool is disposed at an opposite position across the rotation shaft.   The annular groove is formed according to any one of claims 1 to 3, wherein the shape from one end to the other end in the axial direction of the rotating shaft and the shape from the other end to the one end are asymmetric. Power tools.

Images