JP2007175837A - Hammering tool - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hammering tool capable of effectively absorbing vibration due to a drive of a hammering element. <P>SOLUTION: A counter weight unit 53 is disposed in a sub cylinder 32B. The counter weight 50 is made of a magnetic body, and slidably disposed in the sub housing 32B in the longitudinal direction. A second spring 51 is made of a nonmagnetic body and interposed between the counter weight 50 and a damping housing 32 in the front side and a third spring 52 is made of nonmagnetic body, and interposed between the counter weight 50 and the damping housing 32 in the rear side of the counter weight 50. The magnetic generation body 54 is coaxially fixed at the position opposed to the counter weight 50 of a crankshaft 34, and rotated together with the rotation of the crankshaft 34. The magnetic generation body 54 is equipped with a permanent magnet and the nonmagnetic body which are not shown in a figure. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an impact tool, and more particularly to an impact tool having a vibration control mechanism.

  Conventionally, hitting tools having a vibration control mechanism have been proposed. For example, in an impact tool including a casing made up of a handle portion, a motor housing, and a gear housing connected to each other, an electric motor is accommodated in the motor housing, and the gear housing includes a motion conversion housing, a vibration damping housing, and an impact housing. It has. A motion conversion mechanism for converting the rotational motion of the electric motor into reciprocating motion is provided in the motion conversion housing. A cylinder extending in a direction orthogonal to the rotation axis of the electric motor is provided in the striking housing. A tool holding portion is provided on the tip side of the cylinder, and the tip tool is detachably attached.

  Further, the cylinder is provided with a piston slidably on its inner periphery. The piston is reciprocated along the inner circumference of the cylinder by the motion conversion mechanism. A striker is slidably provided on the inner periphery of the cylinder at the tip side in the cylinder. An air chamber is defined in the cylinder and between the piston and the striker. On the tip side of the striker, an intermediate element is provided in the cylinder so as to be slidable in the front-rear direction. The above-described tip tool is located on the tip side of the meson.

  The vibration damping housing is provided on the side of the impact housing and communicates with the impact housing through an air passage. A space defined by the vibration control housing, the counterweight, the striking housing, the cylinder, and the piston is configured to be a sealed space. A counterweight capable of reciprocating in parallel with the reciprocating direction of the piston and two springs provided at both ends of the counterweight are disposed in the vibration damping housing.

  The rotational driving force of the electric motor is transmitted to the motion conversion mechanism, and the piston is reciprocated in the cylinder by the motion conversion mechanism. Due to the reciprocating motion of the piston, the pressure of the air in the air chamber repeatedly rises and falls, giving a striking force to the striker. The striking element moves forward and collides with the rear end of the intermediate element, and the striking force is transmitted to the tip tool via the intermediate element. Thereby, a work material is crushed.

Further, when the piston moves to the tip side during the operation of the impact tool, the space defined by the vibration control housing, the counter weight, the impact housing, the cylinder, and the piston is a sealed space. Move to the rear end. Conversely, when the piston moves to the rear end side, the counterweight moves to the front end side. Thus, the counterweight is configured to reciprocate in conjunction with the reciprocating motion of the piston. (For example, refer to Patent Document 1).
JP 2004-299036 A

  However, in the above-described impact tool, the vibration control housing and the impact housing must be communicated with each other through an air passage, and the space defined by the vibration suppression housing, the counterweight, the impact housing, the cylinder, and the piston needs to be a sealed space. Therefore, the structure of the impact tool is complicated and expensive. Further, a lubricant for maintaining lubricity is enclosed around the cylinder and the piston around the impact tool. As the impact tool is used, the lubricant may move to the air passage, and the operation of the counterweight may be affected. Furthermore, since the vibration-damping housing is provided on the side of the striking housing, work on the side of the wall and the like is reduced.

  Therefore, an object of the present invention is to provide an impact tool that can solve the above-described problems and can effectively absorb vibration caused by driving of the impactor.

  In order to achieve the above object, the present invention provides a housing, an electric motor accommodated in the housing and generating a rotational driving force, a cylinder accommodated in the housing, and a slidable inner periphery of the cylinder. A striking tool comprising: a piston, a motion converting unit that converts a rotational driving force of the electric motor into a reciprocating motion of the piston, and a striking element driven by the reciprocating motion of the piston. Provided is a striking tool comprising a magnetic body, a magnetic force generator that is rotated by the rotational driving force of the electric motor, and a counterweight made of the magnetic body and driven by the magnetic force of the permanent magnet of the magnetic generator. is doing.

  Here, it is preferable to further have an elastic body that urges the counterweight toward the magnetic force generator.

  Furthermore, the counterweight is preferably made of a permanent magnet.

  The electric motor further includes an output shaft that outputs a rotational driving force of the electric motor, and a transmission shaft that transmits the rotational driving force generated by the rotation of the output shaft to the motion conversion unit, and the magnetic force generator includes the transmission shaft. It is preferable to be fixed to.

  A tip tool that is reciprocally driven by the striking force of the striker; a tool holding portion that is rotatably provided to hold the tip tool; an output shaft that outputs a rotational driving force of the electric motor; and the output A first transmission shaft that transmits a rotational driving force due to rotation of the shaft to the motion conversion unit; and a second transmission shaft that transmits a rotational driving force due to rotation of the output shaft to the tool holder. It is preferable that the generator is fixed to the second transmission shaft.

  In addition, it is preferable to further include a first elastic body that urges the counterweight toward the sub-piston, and a second elastic body that urges the counterweight toward the counter-piston direction.

  Moreover, when the said striker moves to the said piston side, it is preferable that the said counterweight moves to the said piston side by the magnetic force of the said permanent magnet.

  Moreover, when the said striker moves to the said piston side, it is preferable that the said counterweight moves to the said piston side with the magnetic force of the said permanent magnet.

  Moreover, it is preferable that the said permanent magnet is provided with two or more along the rotation direction of the said magnetic force generation body.

  Moreover, it is preferable that the magnetic poles of the permanent magnets adjacent to each other on the side away from the rotation axis of the magnetic force generator are different magnetic poles.

  According to the striking tool of claim 1, the permanent magnet is composed of a permanent magnet and a non-magnetic material, and includes a magnetic body that rotates by the rotational driving force of the electric motor, and the magnetic body. Since the counterweight to be driven is provided, vibration due to driving of the striker can be reduced, and the operability of the impact tool can be improved.

  According to the impact tool of the second aspect, the impact tool further includes an elastic body that biases the counterweight toward the magnetic force generator. Therefore, since the counter weight is driven by the magnetic force of the permanent magnet of the magnetic force generator and the biasing force of the elastic body, the counter weight can be driven more appropriately.

  According to the striking tool of the third aspect, since the counter weight is made of a permanent magnet, the counter weight can be driven with respect to the magnetic force of the permanent magnet of the magnetic force generator.

  The impact tool according to claim 4 further includes an output shaft that outputs the rotational driving force of the electric motor, and a transmission shaft that transmits the rotational driving force generated by the rotation of the output shaft to the motion conversion unit, and generates magnetic force. Since the body is fixed to the transmission shaft, it is not necessary to newly provide a shaft for fixing the magnetic force generator, and the striking tool can be simplified.

  According to the striking tool according to claim 5, a tip tool that is reciprocally driven by a striking force of the striking element, a tool holding portion that is rotatably provided to hold the tip tool, and a rotational driving force of the electric motor. Output shaft, a first transmission shaft that transmits the rotational driving force due to the rotation of the output shaft to the motion converting portion, and a second transmission shaft that transmits the rotational driving force due to the rotation of the output shaft to the tool holding portion. Since the magnetic force generator is fixed to the second transmission shaft, it is not necessary to newly provide a shaft for fixing the cam, and the striking tool can be simplified. Furthermore, in addition to the impact force, a rotational force can be applied to the tip tool.

  The striking tool according to claim 6 further includes a first elastic body that biases the counterweight toward the sub-piston, and a second elastic body that biases the counterweight toward the counter-piston direction. Therefore, since the counter weight is driven by the permanent magnet and the elastic body of the magnetic force generator, the counter weight can be driven more appropriately.

  According to the striking tool according to claim 7 and 8, when the striker moves to the piston side, the counterweight moves to the anti-piston side by the magnetic force of the permanent magnet, and the striker moves to the anti-piston side. When the counterweight moves to the piston side due to the magnetic force of the permanent magnet, the occurrence of vibration due to the driving of the striker can be reduced, and the operability of the impact tool can be improved.

  According to the striking tool of claim 9 and 10, a plurality of permanent magnets are provided along the rotation direction of the magnetic force generator, and the magnetic poles on the side away from the rotation axis of the magnetic generators of the permanent magnets adjacent to each other are Since the magnetic poles are of different types, the different types of magnetic poles can be applied to the counterweight including the permanent magnet portion, and the counterweight can be reciprocated more appropriately.

  A striking tool according to a first embodiment of the present invention will be described with reference to FIGS. 1 to 7B. In the following description, the left side in FIG. 1 is the front end side of the impact tool 1 and the right side is the rear end side of the impact tool 1. The impact tool 1 includes a casing including a handle portion 10, a motor housing 20, and a gear housing 30 that are connected to each other.

  A power cable 11 is attached to the handle portion 10 and a switch mechanism 12 is built therein. A trigger 13 that can be operated by a user is mechanically connected to the switch mechanism 12. The power cable 11 is connected to an external power source (not shown) and operates the trigger 13 to switch between connection and disconnection of an electric motor 21 and an external power source, which will be described later.

  The motor housing 20 is provided at the lower end on the front end side of the handle portion 10. The electric motor 21 is accommodated in the motor housing 20. The electric motor 21 includes an output shaft 22 that outputs the rotational driving force. A pinion gear 23 is provided at the tip of the output shaft 22 and is located in the gear housing 30.

  The gear housing 30 includes a motion conversion housing 31, a vibration damping housing 32, and a striking housing 33. The motion conversion housing 31 is located at the upper part of the motor housing 20, and the rear end thereof is connected to the handle portion 10. The striking housing 33 is located in the upper part of the motor housing 20, and the damping housing 32 is located between the striking housing 33 and the motor housing 20 (see also FIG. 2).

  A crankshaft 34 extending parallel to the output shaft 22 is rotatably supported in the motion conversion housing 31. A first gear 35 that meshes with the pinion gear 23 is coaxially fixed to the lower end of the crankshaft 34. A motion conversion mechanism 36 is provided at the upper end of the crankshaft 34. The motion conversion mechanism 36 will be described with reference to FIG. 3A, which is a horizontal sectional view taken along line III (a) -III (a) in FIG. The motion conversion mechanism 36 includes a crank weight 37, a crank pin 38, and a connecting rod 39. The crank weight 37 is fixed to the upper end of the crankshaft 34 (FIG. 1). The crank pin 38 is fixed to the end of the crank weight 37. A crank pin 38 is inserted at the rear end of the connecting rod 39.

  As shown in FIG. 1, a cylinder 40 extending in a direction orthogonal to the output shaft 22 is provided in the striking housing 33. The central axis of the cylinder 40 and the rotation axis of the output shaft 22 are located on the same plane. Further, the rear end portion of the cylinder 40 faces the electric motor 21. A plurality of intake holes 40 a are formed in the cylinder 40. A tool holding portion 60 is provided on the tip side of the cylinder 40, and a tip tool 61 is detachably attached. A slide sleeve 41 slidable in the front-rear direction is provided on the outer periphery of the cylinder 40 so as to open and close the plurality of intake holes 40a. The slide sleeve 41 is urged forward by the first spring 42.

  A piston 43 is provided in the cylinder 40 so as to be slidable on the inner periphery thereof. The piston 43 has a piston pin 43 </ b> A, and the piston pin 43 </ b> A is inserted at the tip of the connecting rod 39. A striking piece 44 is slidably provided on the inner periphery of the cylinder 40 at the tip end side in the cylinder 40. An air chamber 45 is defined in the cylinder 40 and between the piston 43 and the striker 44.

  On the tip side of the striker 44, an intermediate element 46 is provided in the cylinder 40 so as to be slidable in the front-rear direction. A sleeve 47 is provided on the outer periphery of the rear end side of the intermediate element 46. The rear end portion of the sleeve 47 is in contact with the slide sleeve 41. A damper 48 and a damper holder 49 are arranged on the outer periphery of the rear end side of the intermediate element 46. The tip tool 61 described above is located on the tip side of the intermediate element 46.

  The damping housing 32 is formed with a communication hole 32 a that extends in parallel with the cylinder 40 and communicates with the outside air and the motion conversion housing 31. A sub cylinder 32B is provided in the communication hole 32a. A counterweight unit 53 is disposed in the sub cylinder 32B. The counterweight unit 53 is disposed on the cylinder 40 side with respect to the center of gravity G of the impact tool 1.

  As shown in FIG. 3B, the counter weight unit 53 includes a counter weight 50, a second spring 51, a third spring 52, and a magnetic force generator 54. The counterweight 50 is made of a magnetic material and is slidable in the front-rear direction within the sub-housing 32B. The sliding direction of the center of gravity of the counterweight 50 is configured to be on the same plane as the central axis of the cylinder 40 and the rotation axis of the output shaft 22. The second spring 51 is made of a nonmagnetic material, and is interposed between the counterweight 50 and the vibration damping housing 32 on the front side of the counterweight 50, and the third spring 52 is made of a nonmagnetic material, and the counterweight 50 On the rear side, it is interposed between the counterweight 50 and the vibration control housing 32.

  The magnetic force generator 54 is coaxially fixed at a position facing the counterweight 50 of the crankshaft 34 and rotates with the rotation of the crankshaft 34. The magnetic force generator 54 has a disk shape as shown in FIG. 3B, and includes a permanent magnet 54A and a non-magnetic material 54B.

  Next, the operation of the impact tool 1 according to the first embodiment will be described. The tip tool 61 is pressed against a work material (not shown) in a state where the handle portion 10 is gripped by hand. Thereby, the tip tool 61 and the intermediate element 46 are pushed toward the rear end side, and the rear end portion 47A of the sleeve 47 pushes the slide sleeve 41 toward the rear end side against the urging force of the first spring 42. By the retraction of the slide sleeve 41, the intake hole 40a is closed, and the air chamber 45 becomes a sealed space.

  Next, the trigger 12 is pulled, and electric power is supplied to the electric motor 21 to rotate it. This rotational driving force is transmitted to the crankshaft 34 via the pinion gear 23 and the first gear 35. The rotation of the crankshaft 34 is converted into a reciprocating motion of the piston 43 in the cylinder 40 by the motion conversion mechanism 36 (crank weight 37, crankpin 38, and connecting rod 39). Due to the reciprocating motion of the piston 43, the pressure of the air in the air chamber 45 repeatedly rises and falls, giving a striking force to the striking element 44. The striking element 44 advances and collides with the rear end of the intermediate element 46, and the striking force is transmitted to the tip tool 61 through the intermediate element 46. Thereby, a work material is crushed.

  Next, the operation of the counter weight unit 53 during the operation of the impact tool 1 will be described with reference to FIGS. 3 (a) to 7 (b). FIG. 4 shows the relationship between the rotation angle (horizontal axis) of the crankshaft 34 (crankweight 37) and the positions (vertical axis) of the piston 43, the striker 44 and the counterweight 50. The horizontal axis is defined with the counterclockwise direction of the crankshaft 34 as the positive direction, and the state of the crankshaft 34 shown in FIGS. 3A and 3B is 0 °. The vertical axis is defined as the direction in which the rear end side increases. Curve A indicates the position of the piston 43, curve B indicates the position of the striker 44, and curve C indicates the position of the counterweight 50. 3 (a) and 3 (b) correspond to the 0 ° and 360 ° states, and FIGS. 5 (a) and 5 (b) correspond to the 90 ° state and FIG. 6 (a). 6B corresponds to a state of 180 ° (−180 °), and FIGS. 7A and 7B correspond to a state of 270 ° (−90 °).

  The state where the crankshaft 34 is at −180 ° in FIGS. 6A and 6B will be described as a starting point. 6A and 6B, both the piston 43 and the striker 44 (not shown in FIG. 6A) are located on the most distal side. Next, as shown in FIG. 7A, the piston 43 moves to the rear end side by the rotation of the crankshaft 34. As a result, the pressure of the air in the air chamber 45 is reduced, and the striker 44 is pulled to the rear end side due to the pressure drop, and moved to the rear end side by a repulsive force due to a collision with the intermediate element 46 described later. At this time, the non-magnetic material 54B of the magnetic force generator 54 is in close proximity to the counterweight 50.

  Next, the piston 43 moves most to the rear end side by the rotation of the crankshaft 34 (FIG. 3A), and further moves to the front end side by the rotation of the crankshaft 34 (FIG. 5A). At this time, the striker 44 moves to the rear end side due to the above-described inertia of the air pull and the repulsive force caused by the collision with the intermediate piece 46 described later. When the rotation angle of the crankshaft 34 is approximately 110 ° due to the movement of the piston 43 toward the front end side and the movement toward the rear end side of the striker 44, the piston 43 and the striker 44 come closest to each other, and the air chamber The pressure of the air in 45 rises most. Due to the increase in the air pressure, the striker 44 moves to the tip side vigorously.

  When the rotation angle of the crankshaft 34 is about 170 °, the striker 44 is located on the most distal end side and collides with the rear end of the intermediate piece 46, and the strike force of the striker 44 passes through the intermediate piece 46. It is transmitted to the tool 61. At the same time, the permanent magnet 54A rotates to a position facing the counterweight 50, and the counterweight 50, which is a magnetic body, is pulled to the rearmost end side by the magnetic force of the permanent magnet 54A. At this time, the third spring 52 is compressed.

  Next, the rotation of the crankshaft 34 causes the permanent magnet 54 </ b> A to move away from the position facing the counterweight 50. Thereby, the counterweight 50 is released from the magnetic force of the permanent magnet 54A, and moves to the tip side by the urging force of the compressed third spring 52 (FIG. 9B). At this time, the striker 44 moves to the rear end side as described above.

  Thus, according to the impact tool 1 of the present embodiment, when the impact element 44 moves to the front end side, the counterweight 50 is moved to the rear end side, and when the impact element 44 moves to the rear end side. Can move the counterweight 50 to the tip side. Thereby, generation | occurrence | production of the vibration by the drive of the striker 44 can be reduced, and the operativity of the impact tool 1 can be improved. In the present embodiment, since the counterweight 50 is driven by the urging force of the permanent magnet 54A, the second spring 51, and the third spring 52, the counterweight 50 can be driven more appropriately. Further, since the magnetic force generator 54 is fixed to the crankshaft 34, it is not necessary to newly provide a shaft for fixing the magnetic force generator 54, and the striking tool 1 can be simplified. In addition, the configuration of the hitting tool 1 as described above eliminates the need to form an air passage as in the conventional hitting tool. Therefore, the counterweight 50 made of lubricant applied around the cylinder 40 and the piston 43 is used. The influence on the operation can be suppressed.

  Next, an impact tool 101 according to a second embodiment of the present invention will be described with reference to FIGS. 1 and 8 to 12B. The same members as those in the first embodiment are denoted by the same reference numerals, description thereof is omitted, and only different portions are described.

  As shown in FIG. 9B, the counter weight unit 153 includes a counter weight 150, a second spring 51, a third spring 52, and a magnetic force generator 154. The counterweight 150 has a permanent magnet portion 150A and is arranged so that the N pole is located on the rear end side. Further, the counter weight 150 is disposed so as to be slidable in the front-rear direction within the sub-cylinder 32B. The sliding direction of the center of gravity of the counterweight 150 is configured to be on the same plane as the central axis of the cylinder 40 and the rotation axis of the output shaft 22.

  The magnetic force generator 154 is coaxially fixed at a position facing the counterweight 150 of the crankshaft 34 and rotates with the rotation of the crankshaft 34. The magnetic force generator 154 has a disk shape as shown in FIG. 9B, and includes a first permanent magnet 154A, a second permanent magnet 154B, and a non-magnetic body 154C. The first permanent magnet 154A is arranged so that the N pole is located on the outer peripheral side of the magnetic force generator 154, and the second permanent magnet 154B is arranged so that the S pole is located on the outer peripheral side of the magnetic force generator 154. Yes.

  The operation of the impact tool 101 in the present embodiment is substantially the same as the operation of the impact tool 1 in the first embodiment, but the movement of the counterweight unit 153 is different. Therefore, the operation of the counterweight unit 153 will be described with reference to FIGS. 8 to 12B. FIG. 8 is a diagram corresponding to FIG. 4 of the second embodiment. FIGS. 9A to 12B are diagrams corresponding to FIGS. 3A and 3B and FIGS. 5A to 7B of the second embodiment, respectively. It is.

  The state where the crankshaft 34 is at −180 ° in FIGS. 11A and 11B will be described as a starting point. 11A and 11B, the piston 43 and the striker 44 (not shown in FIG. 11A) are both located on the most distal side. Next, as shown in FIG. 12A, the piston 43 moves to the rear end side by the rotation of the crankshaft 34. As a result, the pressure of the air in the air chamber 45 is reduced, and the striker 44 is pulled toward the rear end side due to the decrease in the air pressure, and is moved toward the rear end side due to the repulsive force caused by the collision with the intermediate element 46 described later. . At this time, the non-magnetic body 154C of the magnetic force generator 154 faces the counterweight 150.

  Next, the piston 43 moves most to the rear end side by the rotation of the crankshaft 34 (FIG. 9A), and further moves to the front end side by the rotation of the crankshaft 34 (FIG. 10A). At this time, the striker 44 moves to the rear end side due to the above-described inertia of the air pull and the repulsive force caused by the collision with the intermediate piece 46 described later. Then, as shown in FIG. 10B, the first permanent magnet 154A faces the counterweight 150. In the first permanent magnet 154A, the N pole is located on the outer peripheral side of the magnetic force generator 154, and the N pole of the permanent magnet portion 150A is located on the rear end side. Therefore, the first permanent magnet 154A and the counterweight 150 are Repel each other. Thereby, the counterweight 150 moves to the tip side, and the second spring 51 is compressed.

  Further, when the rotation angle of the crankshaft 34 is about 110 ° due to the movement of the piston 43 toward the front end side and the movement toward the rear end side of the striking element 44, the piston 43 and the striking element 44 come closest to each other, and the air chamber The pressure of the air in 45 rises most. Due to the increase in air pressure, the striker 44 moves to the tip side vigorously. When the rotation angle of the crankshaft 34 is about 170 °, the striker 44 is located on the most distal end side and collides with the rear end of the intermediate piece 46, and the strike force of the striker 44 passes through the intermediate piece 46. It is transmitted to the tool 61.

  At this time, the second permanent magnet 154B faces the counterweight 150. In the second permanent magnet 154B, the S pole is located on the outer peripheral side of the magnetic force generator 154, and the N pole of the permanent magnet portion 150A is located on the rear end side. Therefore, the second permanent magnet 154B and the counterweight 150 are Inquire. Due to this attractive force and the urging force of the second spring 51, the counterweight 150 moves to the rear end side vigorously. Thereby, the third spring 52 is compressed.

  Next, the rotation of the crankshaft 34 causes the second permanent magnet 154 </ b> B to move away from the position facing the counterweight 150. Thereby, the counterweight 150 is released from the magnetic force of the second permanent magnet 154B, and moves to the distal end side by the urging force of the compressed third spring 52 (FIG. 12B). At this time, the striker 44 moves to the rear end side as described above. Thus, in this embodiment, when the striker 44 moves to the front end side, the counter weight 250 is moved to the rear end side, and when the striker 44 moves to the rear end side, the counter weight 250 is moved. Can be moved to the tip side. Thereby, generation | occurrence | production of the vibration by the drive of the striker 44 can be reduced, and the operativity of the impact tool 101 can be improved.

  In the present embodiment, the magnetic force generator 154 includes a first permanent magnet 154A in which the N pole is located on the outer peripheral side of the magnetic force generator 154 and a second permanent magnet in which the S pole is located on the outer peripheral side of the magnetic force generator 154. Since 154B is provided, different types of magnetic poles can be applied to the counterweight 150 including the permanent magnet portion 150A, and the counterweight 150 can be more appropriately reciprocated. Further, the other effects of the impact tool 101 are the same as the effects of the impact tool 1 of the first embodiment.

  Next, an impact tool 201 according to a third embodiment of the present invention will be described with reference to FIG. The same members as those in the first embodiment are denoted by the same reference numerals, description thereof is omitted, and only different portions are described.

  As shown in FIG. 13, a rotary cylinder 70 extending in a direction orthogonal to the output shaft 22 is rotatably supported in the impact housing 33. A first bevel gear 70 </ b> A is provided at the rear end of the rotating cylinder 70. The central axis of the rotation cylinder 70 and the rotation axis of the output shaft 22 are located on the same plane. Moreover, the tool holding part 60 is provided in the front end side of the rotation cylinder 70, and the front-end tool 61 is detachably attached. The cylinder 40 is provided on the inner periphery of the rotating cylinder 70.

  A second gear 71 is coaxially fixed to the crankshaft 34 below the first gear 35. A rotation transmission shaft 72 extending in parallel with the output shaft 22 is rotatably supported in the motion conversion housing 31. A third gear 73 that meshes with the second gear 71 is coaxially fixed to the lower end of the rotation transmission shaft 72. At the upper end of the rotation transmission shaft 72, a second bevel gear 72A that meshes with the first bevel gear 70A is provided. The magnetic force generator 54 is fixed to the rotation transmission shaft 72. Further, the deceleration rates of the crankshaft 34 and the rotation transmission shaft 72 with respect to the output shaft 22 are configured to be equal.

  The rotational driving force of the electric motor 21 is transmitted to the rotation transmission shaft 72 via the pinion gear 23, the first gear 35, the second gear 71, and the third gear 73. The rotation of the rotation transmission shaft 72 is transmitted to the rotation cylinder 70 via the second bevel gear 72A and the first bevel gear 70A, and the rotation cylinder 70 rotates. In the transmission of rotation from the rotation transmission shaft 72 to the rotation cylinder 70, the rotation speed is reduced. Further, a rotational force is applied to the tip tool by the rotation of the rotary cylinder 70. As in the first and second embodiments, a striking force by the piston 43 and the striking element 44 is applied to the tip tool 61. Therefore, in the impact tool 201 of the present embodiment, a rotational force and an impact force are applied to the tip tool 61. Further, since the magnetic force generator 54 is fixed to the rotation transmission shaft 72, it is not necessary to newly provide a shaft for fixing the magnetic force generator 54, and the impact tool 1 can be simplified. Moreover, the other effect of the impact tool 201 of this Embodiment is the same as the effect of the impact tool 1 of 1st Embodiment.

  In addition, the impact tool of this invention is not limited to embodiment mentioned above, A various deformation | transformation and improvement are possible in the range described in the claim. For example, the counterweight unit 53 of the impact tool 201 according to the third embodiment is the same as the impact tool 1 according to the first embodiment, but is the same as the counterweight unit 153 according to the second embodiment. It's okay. Further, the first gear 35 may be thickened to the position where the magnetic force generator 54 is disposed so that the first gear 35 has the function of the magnetic force generator 54. In the third embodiment, the rotary cylinder 70 is rotatably provided, the tool holding unit 60 is rotationally engaged with the rotary cylinder 70, and the first bevel gear 70A of the rotary cylinder 70 and the second bevel gear of the rotation transmission shaft 72 are provided. The rotational force is transmitted to the tip tool 61 by engaging with 72A. However, the tip tool 61 may be rotatably provided separately from the rotary cylinder 70, and the tip tool 61 and the rotation transmission shaft 72 may be engaged to transmit the rotational force to the tip tool 61.

Sectional drawing of the impact tool by the 1st and 2nd embodiment of this invention. The front view of the impact tool by the 1st Embodiment of this invention. FIG. 3 is a horizontal sectional view taken along line III (a) -III (a) in FIG. 1. FIG. 3 is a horizontal sectional view taken along line III (b) -III (b) in FIG. 1. The figure which shows the relationship between the rotation angle of the crankshaft (crankweight) of the impact tool by the 1st Embodiment of this invention, and the position of a piston, a striker, and a counterweight. Explanatory drawing of operation | movement of the piston and striker of the impact tool by the 1st Embodiment of this invention. Explanatory drawing of operation | movement of the counterweight unit of the impact tool by the 1st Embodiment of this invention. Explanatory drawing of operation | movement of the piston and striker of the impact tool by the 1st Embodiment of this invention. Explanatory drawing of operation | movement of the counterweight unit of the impact tool by the 1st Embodiment of this invention. Explanatory drawing of operation | movement of the piston and striker of the impact tool by the 1st Embodiment of this invention. Explanatory drawing of operation | movement of the counterweight unit of the impact tool by the 1st Embodiment of this invention. The figure which shows the relationship between the rotation angle of the crankshaft (crankweight) of the impact tool by the 2nd Embodiment of this invention, and the position of a piston, a striker, and a counterweight. Explanatory drawing of operation | movement of the piston and striker of the impact tool by the 2nd Embodiment of this invention. Explanatory drawing of operation | movement of the counterweight unit of the impact tool by the 2nd Embodiment of this invention. Explanatory drawing of operation | movement of the piston and striker of the impact tool by the 2nd Embodiment of this invention. Explanatory drawing of operation | movement of the counterweight unit of the impact tool by the 2nd Embodiment of this invention. Explanatory drawing of operation | movement of the piston and striker of the impact tool by the 2nd Embodiment of this invention. Explanatory drawing of operation | movement of the counterweight unit of the impact tool by the 2nd Embodiment of this invention. Explanatory drawing of operation | movement of the piston and striker of the impact tool by the 2nd Embodiment of this invention. Explanatory drawing of operation | movement of the counterweight unit of the impact tool by the 2nd Embodiment of this invention. Sectional drawing of the impact tool by the 3rd Embodiment of this invention.

Explanation of symbols

1, 101, 201 Impact tool, 21 Electric motor, 22 Output shaft, 30 Gear housing, 31 Motion conversion housing, 32 Damping housing, 33 Stroke housing, 34 Crankshaft, 36 Motion conversion mechanism, 37 Crank weight, 38 Crankpin , 39 connecting rod, 40 cylinder, 43 piston, 44 striker, 50, 150 counterweight, 51 second spring, 52 third spring, 53, 153 counterweight unit, 54, 154 magnetic force generator, 54A permanent magnet, 54B non-magnetic Magnetic body, 70 rotating cylinder, 72 rotation transmission shaft, 150A permanent magnet section, 154A first permanent magnet, 154B second permanent magnet, 154C non-magnetic body

Claims (10)

A housing;
An electric motor housed in the housing and generating a rotational driving force;
A cylinder housed in the housing;
A piston slidably provided on the inner periphery of the cylinder;
A motion converter that converts the rotational driving force of the electric motor into the reciprocating motion of the piston;
In a striking tool comprising a striking element driven by the reciprocating motion of the piston,
A magnetic force generator configured by a permanent magnet and a non-magnetic material, and rotated by a rotational driving force of the electric motor;
A striking tool comprising: a counterweight made of a magnetic body and driven by the magnetic force of the permanent magnet of the magnetic force generator.   The impact tool according to claim 1, further comprising an elastic body that urges the counterweight toward the magnetic force generator.   The impact tool according to claim 1, wherein the counterweight is made of a permanent magnet. An output shaft that outputs the rotational driving force of the electric motor; and a transmission shaft that transmits the rotational driving force generated by the rotation of the output shaft to the motion conversion unit,
The impact tool according to claim 1, wherein the magnetic force generator is fixed to the transmission shaft. A tip tool that is driven to reciprocate by the striking force of the striker, a tool holding portion that is rotatably provided to hold the tip tool, an output shaft that outputs the rotational driving force of the electric motor, and A first transmission shaft that transmits a rotational driving force due to rotation to the motion conversion unit; and a second transmission shaft that transmits a rotational driving force due to rotation of the output shaft to the tool holder,
35. The striking tool according to any one of claims 1 to 34, wherein the magnetic force generator is fixed to the second transmission shaft.   The first elastic body that urges the counterweight toward the sub-piston, and the second elastic body that urges the counterweight toward the sub-piston direction. The impact tool according to 1.   2. The striking tool according to claim 1, wherein when the striker moves to the piston side, the counterweight moves to the anti-piston side by the magnetic force of the permanent magnet.   2. The striking tool according to claim 1, wherein the counterweight moves to the piston side by the magnetic force of the permanent magnet when the striking piece moves to the piston side.   The said permanent magnet is provided with two or more along the rotation direction of the said magnetic force generation body, The impact tool as described in any one of Claim 1 to 8 characterized by the above-mentioned.   The impact tool according to claim 9, wherein the magnetic poles of the permanent magnets adjacent to each other on the side away from the rotation axis of the magnetic force generator are different magnetic poles.

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