WO2015155912A1

WO2015155912A1 - Electrically driven tool

Info

Publication number: WO2015155912A1
Application number: PCT/JP2014/084592
Authority: WO
Inventors: 隆如田原; 太輔鵜飼; 祐大杉野
Original assignee: 株式会社マキタ
Priority date: 2014-04-08
Filing date: 2014-12-26
Publication date: 2015-10-15
Also published as: JP2015199167A

Abstract

[Problem] To provide an electrically driven tool in which vibration is reduced in spite of the fact that the electrically driven tool has a reciprocating output section. [Solution] A reciprocating saw (1) has: a motor; a rotating drive shaft (42) driven by the motor; a left crank (50) engaging with the rotating drive shaft (42); a slider (58) driven by the left crank (50) while being eccentric relative thereto; a left counterweight (80) driven by the left crank (50) while being eccentric relative thereto; and a left crank bearing (54) for rotatably supporting the left crank (50). The left counterweight (80) is disposed between the left crank bearing (54) and the left crank (50).

Description

Electric tool

The present invention relates to an electric tool having an output unit that reciprocates, such as a reciprocating cutting tool that reciprocates a blade to cut a workpiece.

As shown in Patent Document 1 below, a reciprocating saw that performs a cutting operation by reciprocating a rod attached with a blade is known.
In this reciprocating saw, the rotational motion output from the electric motor is converted into the reciprocating motion of the rod by the reciprocating motion mechanism.

JP 2002-370123 A

Since the reciprocating saw of Patent Document 1 has a reciprocating mechanism, the blade can be reciprocated to perform a cutting operation, but vibration is generated during the cutting operation. Even if vibrations occur, work assuming vibrations can be performed. However, if vibrations are suppressed, the work becomes even easier.
Accordingly, the main object of the present invention is to provide an electric tool capable of suppressing vibration while having an output unit that reciprocates.

In order to achieve the above object, the invention according to claim 1 is directed to a motor, a first gear driven by the motor, a second gear meshing with the first gear, and the second gear. A slider that is driven centrally, a counterweight that is driven eccentrically with respect to the second gear, and a bearing that rotatably supports the second gear, wherein the bearing and the second gear The counterweight is arranged between them.
In order to achieve the above object, a second aspect of the present invention is directed to a motor, a first gear driven by the motor, a second gear meshing with the first gear, and the second gear. A slider that is driven centrally, a counterweight that is driven eccentrically with respect to the second gear, and a bearing that rotatably supports the second gear, and is provided between the bearing and the counterweight. Further, the slider is arranged.
In order to achieve the above object, the invention according to claim 3 is directed to a motor, a first gear driven by the motor, a second gear meshing with the first gear, and the second gear. A center driven slider, a first counterweight driven eccentrically with respect to the second gear, a second counterweight driven eccentrically with respect to the second gear, and the second gear rotatable. And the first counterweight is disposed between the bearing and the slider, and the slider is disposed between the first counterweight and the second counterweight. It is characterized by being.
In addition to the above object, the invention according to claim 4 achieves the object of further improving vibration proofing and durability by simply realizing a balanced arrangement while ensuring a reliable operation. The first counterweight is connected to the second gear, and the second counterweight is connected to the crank. It is characterized by this.
In order to achieve the above object, the invention according to claim 5 is characterized in that, in the invention, the eccentric position of the first counterweight with respect to the second gear and the eccentric position of the second counterweight with respect to the second gear are: It is characterized by being aligned with each other.
In addition to the above-mentioned object, the invention according to claim 6 can achieve the object of further improving the vibration proof property and durability by making the operation of the counterweight more reliable with a simple configuration. A counterweight guide that can contact the counterweight is provided.

According to the present invention, it is possible to provide an electric tool capable of suppressing vibration while having an output unit that reciprocates.

It is a partial central longitudinal cross-sectional view of the reciprocating saw according to the present invention. FIG. 2 is a partial cross-sectional view taken along line AA in FIG. FIG. 2 is a partial cross-sectional view taken along line BB in FIG. FIG. 2 is a partially omitted perspective view of the front part of FIG. 1. FIG. 2 is a partially omitted perspective view of the front part of FIG. 1. FIG. 2 is a partially omitted perspective view of the front part of FIG. 1.

Hereinafter, embodiments of the present invention and modifications thereof will be described with reference to the drawings as appropriate.
The said form concerns the reciprocating cutting tool as an example of an electric tool, More specifically, it concerns a reciprocating saw.
In addition, this invention is not limited to the said form and the example of a change.

1 is a partial central sectional view of a reciprocating saw 1, FIG. 2 is a partial sectional view taken along line AA in FIG. 1, and FIG. 3 is a partial sectional view taken along line BB in FIG. It is. 4, 5 and 6 are partially omitted perspective views of the front portion of the reciprocating saw 1 (the front housing 22 and the front right inner housing 48b which will be described later are omitted in FIG. 4, and the right crank bearing which will be further described in FIG. 5). 54 and the right counterweight guide 86 are omitted. In FIG. 6, a later-described right counterweight 82 and right crank 52 are omitted). 1 and FIG. 2 is the front of the reciprocating saw 1, the top of FIGS. 1 and 3 is the top of the reciprocating saw 1, and the top of FIG. 2 and the right of FIG. Each direction is determined for convenience of explanation, and may actually change depending on the work material, the orientation of the operator, and the like.
The reciprocating saw 1 includes a power unit 2, a power transmission unit 4 as a reciprocating conversion unit, a rod 6 as an output unit connected to the power transmission unit 4, a counterweight mechanism 8 combined with the rod 6, and a housing for housing these 10, a guide shoe 12 protruding from the front end of the housing 10, and a battery V attached to the rear lower portion of the housing 10.

The housing 10 includes a main body housing 20 that houses the power unit 2, and a front housing 22 that houses the power transmission unit 4, the rod 6, and the counterweight mechanism 8 on the front side of the main body housing 20.
The main body housing 20 is separated into a front part and a rear part, and only the rear part is separated into left and right. The front part of the main body housing 20 is a cylindrical front main body housing 20a, the rear left part of the main body housing 20 is a rear left main body housing 20b, and the rear right part of the main body housing 20 is a rear right main body housing 20c. These are

screws

24, 24 with respect to the rear left main body housing 20b and the rear right main body housing 20c with the rear end of the front main body housing 20a aligned with the front end portions of the rear left main body housing 20b and the rear right main body housing 20c.・ Associating each other by passing left and right.
The rear portion of the main body housing 20 is formed in a loop shape, and the rear portion of the loop is a handle portion 26 that extends in the vertical direction. A trigger-type switch 28 is disposed on the front side of the handle portion 26.
The front housing 22 is separated into right and left, and includes a front left housing 22a and a front right housing 22b. The front left housing 22a and the front right housing 22b are fixed to each other by a plurality of left and

right screws

30, 30,... With the front end portion of the front main body housing 20a sandwiched therebetween.
A front left inner housing 48a, a front right inner housing 48b, or a base plate 48c, which will be described later, also has a function as a housing 10 that houses the power transmission unit 4, the rod 6, and the counterweight mechanism 8.

The power unit 2 has an electric motor (not shown). The motor drives the rotary drive shaft 42 as the first gear. The rotational drive shaft 42 extends along the front-rear direction and is disposed on the front side of the motor. Teeth are formed around the tip of the rotary drive shaft 42.
The motor is electrically connected to the attachment portion of the battery V and the switch 28 of the handle 26 in the lower rear portion of the main body housing 20, and the battery V is attached so as to be electrically connected at the attachment portion. The motor is supplied with power from the battery V when the switch 28 is turned ON (trigger is pulled).
A fan 44 is disposed outside the rear portion of the rotation drive shaft 42. The fan 44 is fixed to the rotation drive shaft 42.
Exhaust ports 45 through which the exhaust of the fan 44 passes are provided at locations on the rear end of the front left housing 22a and the rear end of the front right housing 22b on the radially outer side of the fan 44 (left and right sides of the fan 44). 45... Are provided. Each exhaust port 45 is formed by arranging a plurality of slits.
A bearing 46 is disposed in front of the fan 44 and around the rotation drive shaft 42. The bearing 46 rotatably receives the rotary drive shaft 42, and includes a rear end portion of a front left inner housing 48a provided on the inner side of the front left housing 22a and a front right inner side provided on the inner side of the front right housing 22b. It is fixed by being sandwiched between the rear ends of the housing 48b.
A horizontal base plate 48c is fixed between a front lower portion of the front left inner housing 48a and the front right inner housing 48b and a front lower portion of the front left housing 22a and the front right housing 22b. The base plate 48c is attached to the front left inner housing 48a and the front right inner housing 48b by

screws

49, 49. The base plate 48c has a horizontal upper surface, and has a plurality of

ribs

48d, 48d,.

The power transmission unit 4 has a bevel tooth meshing with the teeth of the tip of the rotary drive shaft 42 and has a disk-like left crank 50 extending in the front-rear and up-down directions and a shape similar to the left crank 50 (but not having a bevel tooth). A right crank 52 arranged symmetrically with respect to the front and back and upper and lower surfaces, a left crank bearing 54, a right crank bearing 55 that receives the left crank 50 and the right crank 52 so as to be rotatable around a left and right axis; A guide roller 56 that is attached so as to connect the peripheral edge portions of the inner surfaces of the crank 50 and the right crank 52 and a slider 58 that receives the guide roller 56 so as to reciprocate up and down are provided.
The slider 58 can be handled not as a component of the power transmission unit 4 but as a component of the output unit (rod 6).

The left crank 50 as the second gear is disposed on the left front side of the tip of the rotary drive shaft 42 and is eccentric from the center of the innermost umbrella part 50a having the umbrella teeth and the outer surface of the umbrella part 50a. It has the eccentric part 50b which protruded outward in disk shape, and the axial part 50c which protruded outward in the column shape from the outer surface of the eccentric part 50b. The umbrella part 50a is a disk-shaped part which spreads up and down and up and down, and the gradient is provided to the inner peripheral part. The shaft portion 50c is concentric with the umbrella portion 50a.
Since the diameter (number of teeth) of the left crank 50 is larger than the diameter (number of teeth) of the rotation drive shaft 42 of the motor, the rotation of the rotation drive shaft 42 is decelerated by the left crank 50.
The right crank 52 is disposed on the right front side of the distal end portion of the rotary drive shaft 42, and protrudes outward from the innermost base portion 52a, an eccentric portion 52b that protrudes eccentrically from the base portion 52a, and the eccentric portion 52b. The shaft portion 52c is provided. Unlike the umbrella part 50a, the base part 52a does not include an umbrella tooth and does not have a gradient of the outer peripheral part. The eccentric part 52b and the shaft part 52c are the same as the eccentric part 50b and the shaft part 50c of the left crank 50. The eccentric positions of the

eccentric portions

50b and 52b are aligned.
The left crank bearing 54 as a bearing rotatably supports the shaft portion 50c of the left crank 50, and the right crank bearing 55 receives the shaft portion 52c of the right crank 52. The left crank bearing 54 is fixed to the central portion of the front left inner housing 48a, and the right crank bearing 55 is fixed to the central portion of the front right inner housing 48b.
On the outside of the left crank bearing 54, a plate-like bearing stopper 59a for fixing the inner ring is disposed. The bearing stopper 59a is fixed to the center of the shaft portion 50c by a pan head screw 60a. Similarly, a bearing stop 59b and a pan head screw 60b are arranged outside the right crank bearing 55.
On the outside of the bearing stopper 59a and the pan head screw 60a, a hook-shaped bearing retainer 61a that presses the outer ring of the left crank bearing 54 is provided so as to cover the bearing stopper 59a and the pan head screw 60a. The bearing retainer 61a has a flat plate portion that presses the outer ring of the left crank bearing 54 and the front left inner housing 48a inward. Similarly, a bowl-shaped bearing retainer 61b that presses the outer ring of the right crank bearing 55 is provided.

The guide roller 56 is attached to a position that is eccentric with respect to the rotation center of the left crank 50 or the right crank 52, and the eccentric position is opposite to the eccentric positions of the

eccentric portions

50b and 52b (so as to be 180 ° different). Has been placed.
The guide roller 56 is rotatably supported by a short shaft-like pin 62 passed between the left crank 50 and the right crank 52 and can rotate around the pin 62 in the left-right direction.
The slider 58 is a plate-like member that extends in the front-rear and up-down directions, and has a long hole portion 58 a that extends in the up-down direction at the rear portion. A guide roller 56 is contained in the long hole portion 58a. The guide roller 56 can move along the long hole portion 58 a by rotating in the long hole portion 58 a of the slider 58.
When the left crank 50 rotates and the guide roller 56 is displaced (revolved), a displacement component in the front-rear direction of the guide roller 56 is transmitted to the slider 58. Therefore, the slider 58 reciprocates back and forth via the guide roller 56. The vertical displacement component of the revolution of the guide roller 56 is not transmitted to the slider 58 as the guide roller 56 rotates in the slider 58 and reciprocates up and down.
The rotation of the left crank 50 is directly transmitted to the right crank 52 by the pin 62, and the right crank 52 rotates together with the left crank 50.

The rod 6 is a member extending in the front-rear direction, and a blade attachment portion 70 is provided at the front end portion thereof. The blade mounting portion 70 swells up and down and left and right with respect to the round rod-shaped rod base 71 on the rear side. A blade (not shown) is attached to the blade attachment portion 70.
A rod guide 72 is disposed outside the rod base 71. The rod guide 72 has a hole in the front-rear direction having the same diameter as the rod base 71 that receives the rod base 71.
The rod guide 72 is fixed to the front left inner housing 48a and the front right inner housing 48b.
In the front portion of the rod guide 72, annular first seal rings 74a and second seal rings 74b are placed. The first seal ring 74a and the second seal ring 74b are seal members for preventing dust from entering inside, and are elastic bodies, and allow the rod base 71 to move back and forth in the hole of the ring. In contact with The second seal ring 74b is disposed between the front left inner housing 48a or the front right inner housing 48b and the first seal ring 74a. The first seal ring 74a is connected to the second seal ring 74b and the front left inner It is disposed between the housing 48a, the front right inner housing 48b or the seal pressing member 74c.
The rod 6 is guided by the rod guide 72 (and the first seal ring 74a and the second seal ring 74b) and is movable in the front-rear direction.
The rear end portion of the rod base 71 is fixed to the front end portion of the slider 58, and the rod 6 is reciprocated back and forth by a guide roller 56 received by the slider 58.
The blade passes through the guide shoe 12. The guide shoe 12 includes a shoe plate 77 that can contact a workpiece, and a shoe supporter 78 that is disposed between the shoe plate 77 and the base plate 48c. The shoe plate 77 is attached to the front end portion of the shoe supporter 78 through a shaft 79 in the left-right direction, and is rotatable around the shaft 79.

The counterweight mechanism 8 includes a left counterweight 80 and a right counterweight 82, a left counterweight guide 84, and a right counterweight guide 86. Note that the left counterweight guide 84 and the right counterweight guide 86 may belong to the housing.
The left counterweight 80 is a metal plate-like member that spreads up and down and up and down, and has an elliptical hole 80a that is long up and down at the rear. The eccentric portion 50b of the left crank 50 is inserted in the hole 80a.
The right counterweight 82 is similar to the left counterweight 80 and has a hole 82a for receiving the eccentric portion 52b.
When the left crank 50 rotates, the left counterweight 80 receives a force action from the eccentric portion 50b to the hole 80a and reciprocates back and forth. The forward / backward movement of the rod 6 and the forward / backward movement of the left counterweight 80 are in opposite phases (the phases differ by 180 °). When the rod 6 moves forward, the left counterweight 80 moves backward, and when the rod 6 moves backward, the left counterweight 80 Will move forward. The vertical component related to the rotation of the eccentric portion 50b does not act on the left counterweight 80 because the eccentric portion 50b reciprocates in the hole 80a in the vertical direction. The eccentric part 50b slides in the hole 80a.
The right counter weight 82 moves back and forth in the same manner as the left counter weight 80 by the rotation of the right crank 52. Since the right crank 52 rotates in the same manner as the left crank 50, the rotation of the right counter weight 82 is in phase with the rotation of the left counter weight 80.
The left counterweight guide 84 is a bent plate-like member, and is fixed (screwed) to the front left housing 22a. The left counterweight guide 84 includes a left guide base 84a that extends in the front-rear and up-down directions, left

guide support portions

84b, 84b,... That stand horizontally from the upper and lower sides of the left guide base 84a, and the left guide base 84a. It has a circular left hole 84c opened at the rear. The left guide base portion 84a can contact the outer surface of the left counterweight 80, and the left

guide support portions

84b, 84b,... Can contact the upper surface or the lower surface of the left counterweight 80. The left crank bearing 54 and the like enter the left hole portion 84c, and the left hole portion 84c avoids interference with the left crank bearing 54 and the like.
The right counterweight guide 86 is similar to the left counterweight guide 84, and includes a right guide base portion 86a, right

guide support portions

86b, 86b, and a right hole portion 86c. The right counterweight guide 86 is fixed to the front right housing 22b.
The left counterweight guide 84 guides the left counterweight 80 in the front-rear direction and restricts its movement in the front-rear direction, and the right counterweight guide 86 guides the right counterweight 82 in the front-rear direction.

An example of the operation of such a reciprocating saw 1 will be described.
The operator sets the blade on the rod 6 in the stopped state so that the saw blade is in front, and applies the front portion of the shoe plate 77 of the guide shoe 12 to the workpiece. When the stored battery V is attached and the handle portion 26 is gripped and the switch 28 is turned on, power is supplied to the motor, the rotary drive shaft 42 rotates, the left crank 50 rotates, and the pin 62 or the guide roller 56 revolves. Here, the rotation of the left crank 50 is transmitted to the right crank 52 through the pin 62, and the right crank 52 rotates in the same manner as the left crank 50.
As the guide roller 56 revolves, the rod 6 moves back and forth through the slider 58. The guide roller 56 also rotates within the long hole portion 58 a of the slider 58.

The rod 6 moves back and forth in a state where vibration is suppressed by the left counterweight 80 and the right counterweight 82 on both sides that move back and forth symmetrically.
The counterweight mechanism 8 reciprocates the left counterweight 80 and the right counterweight 82 symmetrically with the rod 6. The left counterweight 80 and the right counterweight 82 come into contact with the left counterweight guide 84 and the right counterweight guide 86 and are guided in the front-rear direction when moving back and forth.
When the rod 6 moves forward (FIGS. 1 to 6), the

eccentric portions

50b and 52b of the left crank 50 and the right crank 52 are positioned rearward, and the

holes

80a and 82a of the left counterweight 80 and right counterweight 82 are rearward. The left counterweight 80 and the right counterweight 82 move backward.
When the rod 6 moves rearward, the

eccentric portions

50b and 52b of the left crank 50 and the right crank 52 are positioned forward, and the

holes

80a and 82a of the left counterweight 80 and right counterweight 82 move forward, and the left counterweight 80 and right counterweight 82 move forward.
The left counterweight 80 and the right counterweight 82 have the same weight as each other, and are arranged symmetrically around the rod 6 (slider 58) in the left-right direction, so that a balance is ensured and vibration is prevented. It is possible to improve the property.

When the operator pushes the handle portion 26 while the rod 6 or the blade is in operation, the saw blade on the front side of the blade that moves back and forth hits the workpiece, and the workpiece is cut with the vertical direction as the cutting direction.
When the operator turns off the switch 28, the rotation drive shaft 42 of the motor stops and various back and forth movements stop.

The reciprocating saw 1 includes a motor, a rotary drive shaft 42 driven by the motor, a left crank 50 meshing with the rotary drive shaft 42, a slider 58 driven eccentrically with respect to the left crank 50, and a left crank 50. A left counterweight 80 that is driven eccentrically with respect to the left crankshaft, and a left crank bearing 54 that rotatably supports the left crank 50. A left counterweight is provided between the left crank bearing 54 and the left crank 50. 80 is arranged. Therefore, the reciprocating motion of the left counterweight 80 can be stabilized and the vibration of the rod 6 can be suppressed.
Further, the motor, the rotary drive shaft 42 driven by the motor, the left crank 50 meshing with the rotary drive shaft 42, the slider 58 driven eccentrically with respect to the left crank 50, and eccentric with respect to the left crank 50. The left counterweight 80 is driven, the right counterweight 82 is driven eccentrically with respect to the left crank 50, and the left crank bearing 54 that rotatably supports the left crank 50. A left counterweight 80 is disposed between the slider 54 and the slider 58, and a slider 58 is disposed between the left counterweight 80 and the right counterweight 82. Therefore, the left counterweight 80 and the right counterweight 82 can be arranged on both sides of the slider 58 connected to the rod 6, and the left counterweight 80 and the right counterweight 82 are balanced not only in the front-rear direction but also in the left-right direction. And the vibration of the rod 6 can be sufficiently suppressed.
Further, it has a right crank 52 connected to the left crank 50 via a pin 62, the left counter weight 80 is connected to the left crank 50, and the right counter weight 82 is connected to the right crank 52. . Therefore, it is possible to simply realize a balanced arrangement while ensuring a reliable operation for various members.
In addition, a left counter weight guide 84 (right counter weight guide 86) that can contact the left counter weight 80 (right counter weight 82) is provided. Therefore, the reciprocation of the left counterweight 80 (right counterweight 82) can be made to follow the left counterweight guide 84 (right counterweight guide 86), and the left counterweight 80 (right counterweight 82) reciprocates. The direction of movement can be stabilized and vibration of the rod 6 can be sufficiently suppressed.

In addition, this invention is not limited to the said form, For example, the following changes can be given suitably.
A slider may be disposed between the left crank bearing and the left counterweight.
That is, a motor, a rotary drive shaft driven by the motor, a left crank meshing with the rotary drive shaft, a slider driven eccentrically with respect to the left crank, and a left counterweight driven eccentrically with respect to the left crank And a left crank bearing that rotatably supports the left crank, and a slider may be disposed between the left crank bearing and the left counterweight.
Even in this case, the reciprocating motion of the slider and the left counterweight can be stabilized and the vibration of the rod can be suppressed.

You can form teeth on the right crank and make the right crank the second gear and connect it to the left crank, or you can form teeth on both cranks, or connect them to each other by gears that mesh with both cranks. Also good.
Two cranks may be arranged vertically with respect to the slider and the rod, respectively, and a horizontal counterweight may be combined with each of them to move the counterweight back and forth above and below the slider and rod.
The reciprocating motion of the slider or rod or counterweight may be the vertical direction with respect to the vertical handle portion.
In the reciprocating motion conversion unit, the gear type may be changed, the number of gears may be changed, or a configuration other than the crank may be adopted.
In the counterweight mechanism, the counterweight may be reciprocated in the opposite phase to the rod or the slider by other configurations such as using one or three or more counterweights, or employing a connecting rod instead of the crank.
The shape of the various members can be changed, for example, the shape of the counterweight is a rod shape as a whole and the guide surface shape of the counterweight guide corresponds to the outer surface of the rod. Also, two counterweight guides are provided for one counterweight, the rear left and rear right of the main body housing are integrated, or the front of the main body housing is separated into the front left and front right For example, the number and arrangement of various members can be changed. Furthermore, it can change to the member of another structure which has the same function about various members, such as fixing with a nail | claw part and a latching | locking part instead of fixing by screwing.
The blade may have a blade other than a saw blade.
Instead of power supply by a battery, power supply by a power cord may be used.
The present invention can be applied to reciprocating cutting tools other than reciprocating saws, and can also be applied to electric tools other than reciprocating cutting tools.

1 .. Reciprocating saw (reciprocating cutting tool, electric tool), 42 .. (motor) rotary drive shaft (first gear), 50 .. Left crank (second gear), 52 .. Right crank (crank), 54 .. Left crank bearing (bearing), 58 .. Slider, 62 .. Pin, 80 .. Left counter weight (counter weight, first counter weight), 82 .. Right counter weight (counter weight, second counter weight) ), 84... Left counter weight guide (counter weight guide), 86... Right counter weight guide (counter weight guide).

Claims

A motor,
A first gear driven by the motor;
A second gear meshing with the first gear;
A slider driven eccentrically with respect to the second gear;
A counterweight driven eccentrically with respect to the second gear;
A bearing rotatably supporting the second gear;
Have
The power tool, wherein the counterweight is disposed between the bearing and the second gear.
A motor,
A first gear driven by the motor;
A second gear meshing with the first gear;
A slider driven eccentrically with respect to the second gear;
A counterweight driven eccentrically with respect to the second gear;
A bearing rotatably supporting the second gear;
Have
The power tool, wherein the slider is disposed between the bearing and the counterweight.
A motor,
A first gear driven by the motor;
A second gear meshing with the first gear;
A slider driven eccentrically with respect to the second gear;
A first counterweight driven eccentrically with respect to the second gear;
A second counterweight driven eccentrically with respect to the second gear;
A bearing rotatably supporting the second gear;
Have
The first counterweight is disposed between the bearing and the slider;
The power tool, wherein the slider is disposed between the first counterweight and the second counterweight.
A crank connected to the second gear via a pin;
The first counterweight is connected to the second gear,
The electric power tool according to claim 3, wherein the second counterweight is connected to the crank.
5. The eccentric position of the first counterweight with respect to the second gear and the eccentric position of the second counterweight with respect to the second gear are aligned with each other. Electric tool.
The power tool according to any one of claims 1 to 5, further comprising a counterweight guide that can come into contact with the counterweight.