JP2015066608A - Reciprocating tool - Google Patents

Abstract

A reciprocating tool capable of reducing the weight of a plunger at low cost and reducing vibrations is provided. A power unit 16 that outputs rotational motion, a speed reducing unit 22 that decelerates the rotational motion output from the power unit 16, a connecting piece 31 that is eccentrically provided in the speed reducing unit 22, and a reciprocating motion in the vertical direction. A plunger 36 that moves, and a connector 38 provided on a part of the plunger 36, and by engaging the connector 38 with the connecting piece 31, the rotational movement is converted into the reciprocating movement of the plunger 36. In the jigsaw 11 that reciprocates the mounted tip tool 40, the connector 38 is provided with a single protruding portion 38b, and the connecting piece 31 is provided with an engaging portion 31a that engages with the protruding portion 38b. [Selection] Figure 1

Description

  The present invention relates to a reciprocating tool such as a jigsaw, and more particularly to a reciprocating tool having a motion conversion unit that applies a reciprocating motion to a cutting blade by rotation of a motor.

  FIG. 6 shows a longitudinal sectional structure of a reciprocating cutting tool that performs cutting by converting the rotational force of a motor, which is an electric motor, into reciprocating motion. FIG. 7 shows a perspective view of the plunger. As shown in FIGS. 6 to 7, in this reciprocating tool a, a connecting piece that is circular on the side surface of the gear c that is a reduction gear of the motor b and is close to the outer peripheral portion and is rotatable about its axis. d is attached. The plunger e is provided with a connector f having a U-shaped cross section having a pair of upper and lower guides fa and fb for guiding the connecting piece d so as to be movable in the horizontal direction. The connecting piece d is moved in the horizontal direction to the connector f. Engaged as possible. The connecting piece d moves along a circular orbit by the rotation of the gear c.

  The connector f is fixed to the plunger e, and the plunger e is supported so as to be movable in the vertical direction. Therefore, the rotational motion of the connecting piece d is converted into the reciprocating motion of the connector f in the vertical direction. A saw blade g, which is a blade, is attached to the lower end of the plunger e, and the object can be cut by moving the saw blade g in the manner of a saw. Further, in order to reduce vibration due to the reciprocating motion of the plunger e, the gear c is provided with a balance weight h so as to operate in a phase opposite to that of the plunger e.

JP 2006-175524 A

  In the reciprocating tool a configured as described above, it is considered most effective to reduce the mass of the plunger e in order to reduce vibration. That is, if the plunger e is lightened, the corresponding balance weight h can be lightened.

  However, since the plunger e needs strength for cutting an object, there is a problem that a high-cost material must be used to reduce the weight.

  The present invention has been made to solve the above problems. An object of the present invention is to provide a reciprocating tool capable of reducing the weight of a plunger at low cost and reducing vibration.

  Among the present inventions, the first invention is a power unit that outputs rotational motion, a speed reduction unit that decelerates rotational motion output from the power unit, a connecting piece that is eccentrically provided in the speed reduction unit, and a vertical A plunger that reciprocates in a direction; and a connector provided on a part of the plunger, and by engaging the connector with the connecting piece, the rotational movement is converted into a reciprocating movement of the plunger, A reciprocating tool that reciprocates a tip tool attached to a plunger, wherein the connector is provided with a single protrusion, and the connecting piece is provided with an engaging part that engages with the protrusion.

  Here, it is preferable that the protrusion is a groove. It is preferable that the engaging portion includes a pair of pins facing each other with the protruding portion interposed therebetween. It is preferable that a low friction material is applied to at least one of the protrusion and the engagement portion. In addition, it is preferable that at least one of the protruding portion and the engaging portion is made of a sintered material. Furthermore, it is preferable that at least one of the protruding portion and the engaging portion is tapered toward the tip.

  Of the present invention, the second invention is a power unit that outputs rotational motion, a speed reduction unit that decelerates rotational motion output from the power unit, and a connecting piece that is eccentrically provided in the speed reduction unit, A plunger that reciprocates in a vertical direction; and a connector provided on a part of the plunger, and by engaging the connector with the connecting piece, the rotational movement is converted into a reciprocating movement of the plunger. A reciprocating tool for reciprocating a tip tool attached to the plunger, wherein the connector is provided with a projecting portion, and the connecting piece is sandwiched between the projecting portion in the reciprocating direction of the plunger. And a second engaging portion.

  ADVANTAGE OF THE INVENTION According to this invention, the plunger can be reduced in weight at low cost, and the reciprocating tool which can reduce a vibration can be provided.

It is a longitudinal section showing a jigsaw which is one embodiment of the present invention. It is a principal part expanded sectional view of FIG. It is a perspective view of the connector which transmits motive power to a plunger. It is a perspective view of a connecting piece. It is a perspective view which shows the modification of a connecting piece. It is a longitudinal cross-sectional view which shows the conventional jigsaw. It is a perspective view of the plunger used for the jigsaw of FIG.

  Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an overall structure of a jigsaw 11 that cuts an object 10 as a reciprocating tool. The object 10 includes wood, mild steel plate, and stainless steel. The jigsaw 11 has a tool body 12. The tool body 12 includes a first tube portion 13 extending in the horizontal direction, a second tube portion 14 extending upward from an end portion of the first tube portion 13, an end portion of the first tube portion 13, and an end of the second tube portion 14. And a handle portion 15 that connects the two portions. Here, the horizontal direction is a direction along the surface 10 a of the object 10. The center line of the first cylinder part 13 and the center line of the second cylinder part 14 intersect each other. Moreover, the 2nd cylinder part 14 has an opening part in the front part, and the cover 14a which covers an opening part is provided.

  An electric motor 16 that is a power unit that outputs rotational motion is provided in the first tube portion 13. A rotating shaft 17 that is an output portion of the electric motor 16 is provided with a fan for cooling the electric motor and a pinion 18. A gear holder 19 is provided from the first tube portion 13 to the inside of the second tube portion 14. A rotating shaft 17 is rotatably supported in the first cylinder part via a first bearing 20 attached to the gear holder 19 and a second bearing 20A provided at the rear part of the first cylinder part 13.

  A support shaft 21 is fixed to the gear holder 19 in parallel with the rotation shaft 17, and a gear 22 that is a speed reducing portion is rotatably supported on the support shaft 21. The gear 22 is meshed with the pinion 18. The gear 22 is provided with an eccentric portion 23 continuous with the gear 22. The eccentric portion 23 protrudes from the side surface of the gear 22 in a direction along the rotation center B <b> 1 of the support shaft 21. The outer peripheral shape of the eccentric part 23 is circular, and the center of the eccentric part 23 is eccentric from the rotation center B1.

  A balance weight 24 is attached to the outer periphery of the eccentric portion 23. The balance weight 24 is integrally formed of metal. The balance weight 24 is provided with a long hole 25 penetrating in the direction along the rotation center B <b> 1, and the eccentric portion 23 is disposed in the long hole 25. The long axis of the long hole 25 extends along the horizontal direction. The eccentric part 23 is movable in the horizontal direction within the long hole 25. Further, the balance weight 24 is provided with a linear slit 24a extending in the vertical direction. On the other hand, a guide pin 26 is fixed to the gear holder 19, and the guide pin 26 is disposed in the slit 24a. The guide pin 26 can move in the slit 24a, and the guide pin 26 regulates the movement direction of the balance weight 24 in the vertical direction.

  Further, the holder 27 is fixed to the tip of the eccentric part 23 using a screw 28. The holder 27 is integrally formed of a steel material. A connecting piece 31 is attached to the holder 27 via a needle bearing 30. The connecting piece 31 is formed by integrally forming a steel material into a cylindrical shape. The center line C1 of the connecting piece 31 is eccentric from the rotation center B1 of the gear 22.

  On the other hand, a plunger holder 32 is provided in the second cylindrical portion 14. A support shaft 32a for supporting the upper end of the plunger holder 32 is provided. When the jigsaw 11 is viewed from the front, the plunger holder 32 can be swung within a predetermined angle range. The plunger holder 32 is provided with a first shaft hole 33 and a second shaft hole 34 that penetrate in the direction along the center line D1. The first shaft hole 33 and the second shaft hole 34 are arranged coaxially, and the center line D1 is arranged along the vertical direction, that is, the vertical direction. When the jigsaw 11 is viewed from the front, the center line D1 is perpendicular to the rotation center B1. FIG. 1 shows a case where the center line D1 is substantially perpendicular to the surface 10a of the object 10.

  The plunger holder 32 is provided with an elastic member that urges clockwise around the support shaft 32a within a plane parallel to all of the center lines C1 and D1.

  A plunger 36 made of a steel material is provided inside the tool body 12, and the plunger 36 can move in the direction along the center line D <b> 1 in the first shaft hole 33 and the second shaft hole 34. Needle bearings 37 are respectively provided in the first shaft hole 33 and the second shaft hole 34, and the plunger holder 32 is supported by the two needle bearings 37, 37 so as to be capable of reciprocating in the direction along the center line D1. ing.

  The plunger 36 is provided with two recesses 36a in series from both ends in the longitudinal direction along the center line D1. A solid portion 36b is provided between the concave portions 36a of the plunger 36, and a connector 38 is fixed to the solid portion 36b. The connector 38 is made of steel, and the connector 38 is fixed to the plunger 36 by using a fixing element 44.

  As shown in FIG. 3, the connector 38 has a rectangular plate 38a and a single protrusion (projection) 38b provided along the upper side of the plate 38a. The protruding portion 38 b extends along the width direction E1 of the jigsaw 11. In the embodiment, the width direction E1 is substantially horizontal, and the width direction E1 intersects the center line D1. In the embodiment, the center line D1 and the width direction E1 intersect at a substantially right angle.

  As shown in FIGS. 2 to 4, the connecting piece 31 is provided with an engaging portion 31 a that is slidably engaged with the protruding portion 38 b. The engaging portion 31a is a groove along the horizontal direction. That is, the engaging portion 31a can be called an engaging groove. Focusing on the transmission of force in the reciprocating direction, the engaging portion 31a is positioned above the connecting piece 31, and a first engaging portion that transmits the force in the direction in which the connecting piece 31 protrudes from the tool body 12, and the connecting piece And a second engaging portion that transmits force in a direction in which the connecting piece 31 is pulled back to the tool body 12. That is, the first engaging portion and the second engaging portion are provided so as to sandwich the protruding portion (the protruding portion 38 b) in the reciprocating direction of the plunger 36. The protruding portion 38b has a first pressure receiving surface that can come into contact with the first engaging portion, and a second pressure receiving surface that can come into contact with the second engaging portion.

  Moreover, the engaging part 31a is formed in the taper shape gradually expanded toward the front-end | tip. Corresponding to this, the protrusion 38b is formed in a taper shape in which the cross-sectional dimension (thickness) in the reciprocating direction decreases toward the tip. The holder 27, the connecting piece 31, and the connector 38 constitute a motion conversion mechanism 47. The connector 38 converts the moving force of the connecting piece 31 into the reciprocating motion force of the plunger 36. The gear 22 and the holder 27 are provided in a power transmission path from the electric motor 16 to the plunger 36.

  Further, a grip portion 39 is provided at the lower end of the plunger 36, and the blade 40 is gripped by the grip portion 39. A base 42 having a flat surface is attached to the second cylindrical portion 14, and an opening 42 a of the base 42 is provided. The handle portion 15 is provided with a trigger 15a. A power cord 41 is connected to a boundary portion between the handle portion 15 and the first tube portion 13. A control unit is provided inside the tool body 12. The control unit includes an electric circuit for connecting the power cord 41 and the electric motor 16 and a switch provided in the electric circuit. The control unit connects or disconnects the switch based on the operation of the trigger 15a.

  Next, the operation of the jigsaw 11 will be described. After connecting the power cord 41 to the external power source, the worker holds the handle portion 15 and presses the base 42 against the object 10. When the trigger 15a is operated, a switch is connected, electric power is supplied to the electric motor 16, and the rotating shaft 17 rotates in one direction. When the torque of the rotation shaft 17 is transmitted to the gear 22, the rotation speed of the gear 22 is lower than the rotation speed of the rotation shaft 17. That is, the pinion 18 and the gear 22 are speed reduction mechanisms, and when the torque of the electric motor 16 is transmitted to the holder 27, the rotational speed of the holder 27 is lower than the rotational speed of the rotary shaft 17.

  When the gear 22 rotates about the support shaft 21, the gear 22 and the holder 27 rotate integrally. When the holder 27 rotates about the rotation center B1, the connecting piece 31 revolves around the rotation center B1 in a plane perpendicular to the rotation center B1. Then, the rotational force of the holder 27 is transmitted to the connector 38 via the connecting piece 31, and the connector 38 and the plunger 36 reciprocate in the direction along the center line D1, that is, ascend and descend repeatedly. Then, the blade 10 attached to the plunger 36 is repeatedly raised and lowered, whereby the object 10 is cut by the blade 40. Thus, in the jigsaw 11, the rotational motion of the rotating shaft 17 of the electric motor 16 is converted into the reciprocating motion of the plunger 36 and the blade 40.

  Further, the jigsaw 11 includes an orbital mechanism 50. The orbital mechanism 50 swings the blade 40 within a predetermined angle range with the support shaft 32a as a fulcrum when the plunger 36 moves up and down, and the blade 40 moves to the object 10 in the process in which the plunger 36 moves up. In the process of approaching and lowering the plunger 36, the blade 40 moves away from the object 10. Thereby, it becomes possible to cut efficiently. The orbital mechanism 50 is a well-known technique as described in Japanese Patent Laid-Open No. 2002-077941 and will not be specifically described.

  As described above, according to the jigsaw 11 of the present embodiment, the electric motor 16 that is a power unit that outputs the rotary motion, the gear 22 that decelerates the rotary motion output from the electric motor 16, and the gear 22 By connecting the connecting piece 31 eccentrically to the connecting piece 31, the plunger 36 reciprocating in the vertical direction, the connector 38 provided on a part of the plunger 36, and the connecting piece 38 with the connecting piece 31, In the jigsaw 11 that converts the rotational motion into the reciprocating motion of the plunger 36 and applies the reciprocating motion to the blade 40 attached to the plunger 36, the connector 38 is provided with a single protruding portion 38 b, and the connecting piece 31 is projected. Since the engaging portion 31a that is slidably engaged with the strip portion 38b is provided, the plunger 36 is Can be reduced in weight and cost, it is possible to provide a jigsaw 11 can be reduced vibration.

  In this case, since the engaging part 31a consists of a groove | channel, it is easy to process and the protrusion part 38b can be easily engaged so that sliding is possible. In addition, the groove that is the engaging portion 31a is formed in a tapered shape that gradually expands toward the tip, and the protruding portion 38b is also formed in a tapered shape corresponding to this (see FIG. 3). Assembly and smooth power transmission are possible.

  Since at least one of the protrusions 38b and the engagement parts 31a is coated with a low friction material such as grease or lubricating oil, the friction between the protrusions 38b and the engagement parts 31a can be reduced, Smooth operation can be maintained and durability can be improved. In addition, it is preferable that at least one of the protruding portion 38b and the engaging portion 31a is made of a sintered material that can impregnate and hold the lubricating oil. The low friction material may be a minimum friction material or a minimum ball bearing.

  Next, a second embodiment of the present invention will be described with reference to FIG. In the second embodiment, the entire reciprocating tool has the same structure as that of the first embodiment. In 2nd Embodiment, the engaging part 31a of the connecting piece 31 consists of a pair of pins 31b and 31b which oppose up and down on both sides of a protrusion part. The projecting portion transmits force in the reciprocating direction while sliding with respect to the pins 31b and 31b. Moreover, you may provide a roller rotatably with respect to the pins 31b and 31b in the outer periphery of the pins 31b and 31b. By providing the rollers, the friction of the protrusions with respect to the pins 31b and 31b can be reduced, and power can be transmitted more efficiently.

  The reciprocating tool according to the present invention is not limited to the above-described embodiment, and various modifications can be made within the scope described in the claims. For example, the protruding portion of the connector is not limited to a flat plate shape, and various modifications are possible as long as the protruding portion does not come off the engaging portion in the entire reciprocating process. For example, the connector can be further reduced in weight by providing a notch smaller than the width of the engaging portion in a part of the protruding portion. The reciprocating tool is not limited to a jigsaw and can be applied to a cutting tool, an electric drill, a screw tightener, and the like. The reciprocating tool is a reciprocating tool in which the power of the battery pack attached to the tool body is supplied to the electric motor in addition to the reciprocating tool in which the power of the commercial power source is supplied to the electric motor via the power cord. including. The battery pack contains battery cells, and the battery pack can be attached to and detached from the tool body.

  The reciprocating tool of the present invention includes a tool in which a gear transmission device, a winding transmission device, and a friction transmission device are provided in a power transmission path from a power source to a rotating member. Further, the power source that generates power to be transmitted to the tip tool includes an electric motor, an engine, and a hydraulic motor. The present invention also includes a reciprocating tool for transmitting the power of the power source to the tip tool, such as a hammer, a hammer driver, a hammer drill, a saver saw, and a hedge trimmer.

DESCRIPTION OF SYMBOLS 10 Object 10a Surface 11 Jigsaw 12 Tool main body 13 1st cylinder part 14 2nd cylinder part 14a Cover 15 Handle part 15a Trigger 16 Electric motor (power part)
17 Rotating shaft 18 Pinion 19 Gear holder 20 First bearing 20A Second bearing 21 Support shaft 22 Gear (reduction part)
23 Eccentric portion 24 Balance weight 24a Slit 25 Long hole 26 Guide pin 27 Holder 28 Screw 30 Needle bearing 31 Connecting piece 31a Engaging portion 31b Pin 32 Plunger holder 32a Support shaft 33 First shaft hole 34 Second shaft hole 36 Plunger 36a Recessed portion 36b Solid part 37 Needle bearing 38 Connector 38a Plate 38b Projection part 39 Grasping part 40 Blade (tip tool)
41 Power cord 42 Base 42a Opening 44 Fixing element 47 Motion conversion mechanism 50 Orbital mechanism B1 Center of rotation C1 Center line D1 Center line E1 Width direction

Claims (7)

A power unit that outputs rotational motion, a speed reduction unit that decelerates rotational motion output from the power unit, a connecting piece that is eccentrically provided in the speed reduction unit, a plunger that reciprocates in the vertical direction, and a A connector provided in part, and by engaging the connector with the connecting piece, the rotary motion is converted into the reciprocating motion of the plunger, and the reciprocating motion is given to the tip tool mounted on the plunger. A reciprocating tool,
The reciprocating tool which provided the single protrusion part in the said connector, and provided the engaging part engaged with the said protrusion part in the said connecting piece.   The reciprocating tool according to claim 1, wherein the engaging portion includes a groove.   The reciprocating tool according to claim 1, wherein the engaging portion includes a pair of pins facing each other with the protruding portion interposed therebetween.   The reciprocating tool according to claim 1, wherein a low friction material is applied to at least one of the protruding portion and the engaging portion.   The reciprocating tool according to claim 1, wherein at least one of the protruding portion and the engaging portion is made of a sintered material.   The reciprocating tool according to claim 1, wherein at least one of the protruding portion and the engaging portion has a tapered portion. A power unit that outputs rotational motion, a speed reduction unit that decelerates rotational motion output from the power unit, a connecting piece that is eccentrically provided in the speed reduction unit, a plunger that reciprocates in the vertical direction, and a A connector provided in part, and by engaging the connector with the connecting piece, the rotary motion is converted into the reciprocating motion of the plunger, and the reciprocating motion is given to the tip tool mounted on the plunger. A reciprocating tool,
The reciprocating tool which provided the protrusion part in the said connector, and provided the 1st engaging part and the 2nd engaging part which pinch | interpose the said protrusion part in the reciprocating direction of the said plunger in the said connecting piece.

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