JP3372398B2 - Rotary tool - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary tool used for screw tightening, and more particularly, a rotary tool in which a main body portion for accommodating a motor and a drive body portion for accommodating a drive shaft are bent and arranged in an angle. It is about.

[0002]

2. Description of the Related Art As a rotary tool used for screw tightening, a pistol-type tool has been generally used. However, since this tool has a long length from the rear end to the tip, it can be inserted in a narrow space. It becomes impossible to work in a narrow space.
Therefore, as seen in Japanese Patent Laid-Open No. 6-285771 (see FIG. 4), a vertical main body portion 2 accommodating a motor 1 is accommodated.
There is provided a rotary tool formed into a substantially L-shape (angle type) from the horizontal drive body portion 4 that houses the drive shaft 3 that drives the anvil 20. In this case, since the motor 1 is housed in the vertical main body portion 2, the length of the horizontal drive body portion 2 becomes short, and it can be conveniently used for work in a narrow space.

In such a rotary tool, it is desired to provide a motor control section 13 including a relay 14 and the like so that torque control and rotation speed adjustment of the motor 1 can be performed. . The motor control unit 13 is preferably arranged in the vicinity of the motor 1 in order to turn on and off the electric current to the motor 1. For this reason, as shown in FIG.
It is easily conceivable to provide the rear side of the motor 1 in the main body 2 as shown in FIG. 5A or the lower side of the motor 1 in the main body 2 as shown in FIG. 5B. .

[0004]

However, when the motor control section 13 is arranged on the rear side of the motor 1 as shown in FIG. 5A, the motor control section 13 causes the back side of the main body section 2 to swell and this section Since it projects from the back surface of the rotary tool, this projecting part interferes with work in a narrow space, and when the rotary tool is dropped, the projecting part collides directly with the motor control unit 13 and a shock is applied. Easy,
There is a problem that the motor control unit 13 is likely to fail. In addition, since the vertical length of the rotary tool formed in the angle type is longer than that in the pistol type, the weight balance when gripping the grip 53 of the main body portion 2 becomes poor, but FIG. When the motor control unit 13 is disposed below the motor 1 as described above, the vertical length of the main body unit 2 becomes longer, and the weight balance becomes worse, which makes it difficult to use.

The present invention has been made in view of the above points, and does not interfere with work in a narrow space, is less susceptible to the impact of a drop, and does not adversely affect the weight balance. It is an object of the present invention to provide a rotary tool that can be provided with.

[0006]

SUMMARY OF THE INVENTION According to the present invention, a drive body portion which houses a motor body 1 and a drive shaft 3 which is rotationally driven by the motor 1 and which is arranged at the tip of the body body portion 2 is provided. In the rotary tool in which the housing 27 is formed in a substantially L shape from 4 and 4, the impact torque of tightening is not less than a certain value.
The motor control unit 13 for controlling the motor 1 is arranged in the entry corner space S between the main body 2 and the drive main body 4 to stop the rotation of the motor 1 and limit the torque. And is provided in the housing 27.

Further, according to the present invention, the battery pack 52 is attached to the rear end of the main body portion 2 so as to project in the same direction as the driving body portion 4, and the tip of the drive shaft 3 projecting from the driving body portion 4 and the battery pack. It is characterized in that the motor control section 13 is provided so as to be arranged closer to the main body section 2 than the line connecting the projecting tips of 52. The invention further motor control unit 13 to form comprises a relay 14 provided with an impact mechanism section 11 to drive the body portion 4, the vibration closing direction of the contact 16, 17 of the relay 1 4 by the impact mechanism 11 It is characterized in that the relays 14 are arranged so as not to coincide with the direction.

[0008]

The motor control section 13 for controlling the motor 1 is arranged in the housing corner space between the main body section 2 and the drive body section 4 and provided in the housing 27. Even if it projects from 2, it is housed in this entering corner space S, and the projecting part by the motor control part 13 does not interfere.

[0009]

EXAMPLES The present invention will be described in detail below with reference to examples. 1 to 3 show an embodiment of the present invention, in which a housing 27 is a vertical body portion 2 for accommodating a motor 1,
It is formed by a horizontal drive body portion 4 that houses and supports the drive shaft 3, and the drive body portion 4 is formed in a substantially inverted L shape by projecting to the front surface side of the main body body portion 2.

A bevel gear 6 is fixed to the output shaft 5 of the motor 1, and the bevel gear 6 is fixed by a retaining ring 30 to a bearing 29 enclosed in a motor mount 28 screwed to the motor 1. . A gear shaft 31 provided with a bevel gear 7 that meshes with the bevel gear 6 is pivotally supported on the housing 27 by bearings 32 and 33, and a spur gear 9 is provided on the gear shaft 31.

The drive shaft 3 is composed of a rotary shaft 3a and an anvil 20. The rotary shaft 3a has its rear end pivotally supported by a bearing 34 and its front end in a fitting hole 35 provided in the anvil 20. It is rotatably supported. A cam groove 36 in a direction inclined with respect to the axial direction (X-Y direction) is provided on the outer periphery of the rotary shaft 3a. A spur gear 8 is fixed to the rear end of the rotary shaft 3a, and the spur gear 8 is meshed with the spur gear 9. The anvil 20 is rotatably supported on the housing 27 by bearings 39, and an anvil arm 41 is provided on the outer periphery of the bottom of the anvil 20. Anvil 20
The tip of the drive unit is a mounting portion 42 for mounting the tip tool 19, such as a screwdriver or a wrench, and is projected from the tip of the drive body 4.

A hammer 25 is attached to the outer periphery of the rotary shaft 3a of the drive shaft 3 so as to be slidable in the axial direction (X-Y direction), and a cam groove 45 provided in the inner periphery of the hammer 25 in the axial direction. A ball 46 made of a steel ball is fitted between the rotary shaft 3a and the cam groove 36. Since the ball 46 is thus fitted between the cam grooves 36 and 45, the hammer 2
5 is connected to the rotary shaft 3a, and the ball 46 has a cam groove 3
The hammer 25 moves forwards and backwards in the axial direction (X-Y direction) of the rotary shaft 3a by rolling along 6 and 45, but the hammer 25 is also rotated in accordance with the rotation of the rotary shaft 3a. A spring 12 formed of a coil spring is attached between the hammer 25 and the spur gear 8 so as to urge the hammer 25 toward the anvil 20 side.
By urging the hammer 25 toward the anvil 20 in this manner, the hammer claw 47 provided on the hammer 25 engages with the anvil arm 41 of the anvil 20 and the rotation of the hammer 25 is transmitted to the anvil 20. ing. The impact mechanism section 11 is formed by the anvil 20, the hammer 25, the cam grooves 36 and 45, the ball 46, the spring 12 and the like, and the structure itself of the impact mechanism section 11 is conventionally known.

A lower portion of the main body 2 is formed as a grip 53, and a battery pack 52 for supplying power to the motor 1 is detachably attached to the lower end of the main body 2. The battery pack 52 is formed such that the front end portion thereof protrudes forward from the front surface of the main body portion 2. The motor control unit 13 is provided in the housing 27 so as to be arranged in the entry corner space S between the upper portion of the main body portion 4 that bends in an L shape and the drive body portion 2. That is, the housing 27 of the main body portion 2 is swollen into the inside corner space S, and the motor controller 13 is housed in the swollen portion 21 of the housing 27 on the front side of the motor 1.
By arranging the motor control unit 13 in the entry corner space S in this way, even if the motor control unit 13 projects from the main body portion 2, the motor control unit 13 is housed in this entry corner space S, and when working in a narrow place. The protruding portion of the motor control unit 13 does not interfere with the operation, and the motor control unit 13 is directly bumped by the main body 2 and the drive body 4 even if the power tool is dropped. Therefore, the motor control unit 13 can be prevented from malfunctioning.
Further, by arranging the motor control unit 13 in this way, the height of the main body 2 is not further increased unlike the case of arranging the motor control unit 13 on the lower side of the motor 1, and the weight balance is eliminated. Can be prevented from getting worse.

At this time, the motor control section 13 is located closer to the main body section 4 than the line connecting the tip of the drive shaft 3 protruding from the drive body section 4 (the mounting section 42 of the anvil 20) and the projecting tip of the battery pack 52. It is preferably formed to fit. By disposing the motor control unit 13 in this way, the drive shaft 3 and the battery pack 5 protruding from the drive body unit 4 are arranged.
The motor control unit 13 is housed in a concave space surrounded by the body 2 and the main body unit 4, so that the motor control unit 13 can be prevented from becoming an obstacle, and the motor control unit 13 can be protected from three sides by electric power. When the tool is dropped, the motor controller 13 is less likely to directly hit. In the illustrated embodiment, the battery pack 52, the motor 1, and the impact mechanism section 11 are arranged near the grip 53 so that the weight balance when carrying an electric tool is good. is there.

When the grip 53 is held and the switch button 51 is pressed, the output shaft 5 of the motor 1 is rotationally driven,
This rotational force is transmitted to the rotary shaft 3a of the drive shaft 3 via the bevel gears 6 and 7 and the spur gears 8 and 9, and the drive shaft 3 is rotationally driven. When the rotary shaft 3a is rotationally driven in this manner, the hammer 25 rotates with this rotation, and the anvil arm 41 is engaged with the hammer claw 47 of the hammer 25.
When 0 is rotated, rotation is output to the tip tool attached to the attachment portion 42, and rotation fastening work such as screw tightening can be performed. When rotational fastening work such as screw tightening progresses and a load is applied to the rotation of the anvil 20, a force for relatively rotating the hammer 25 with respect to the anvil 20 acts, so that the hammer 25 moves together with the ball 46 in the cam groove 36. And the hammer claw 47 is disengaged from the anvil arm 41. After disengagement in this way, the hammer 25
When the hammer claw 47 moves over the anvil arm 41 by rotating, the hammer 25 advances in the Y direction by the elastic force of the spring 12, and the hammer claw 47 shock-engages the anvil arm 41 and impacts the anvil 20. Can be rotated. In this way, the rotary tightening work such as screw tightening can be strongly performed by the impact operation due to the rotary impact force.

When performing the rotary tightening work such as the screw tightening as described above, the motor control unit 13 functions to stop the rotation of the motor 1 and control the torque when the impact torque of the tightening exceeds a certain level. Is done. The motor control unit 13 detects the impact of the hammer 25 and the anvil 20 and performs torque control, and a torque control circuit.
It is formed by including a relay 14 for opening and closing the energization of the motor 1 by a signal from the torque control circuit, and a setting dial 22 for setting a limiting torque value in the torque control circuit. The relay 14 is formed by providing a coil 15 and contacts 16 and 17 on the fixed side and the movable side. When the switch button 51 is pressed, the coil 15 is excited and the contact 1
6 and 17 are closed, the motor 1 is energized to operate the motor 1, and the rotary tightening work such as screw tightening can be performed by the impact operation by the viewpoint impact force as described above. Then, when the tightening impact torque reaches the set value, the excitation of the coil 15 is stopped by the signal from the torque control circuit, the contacts 16 and 17 are opened, the power supply to the motor 1 is stopped, and the rotation of the motor 1 is stopped. It is like this.

Here, during the impact operation by the impact mechanism 11, the hammer 25 is moved in the axial direction of the drive shaft 3 (X-
The rotary tool vibrates in the XY directions in order to move forward and backward in the Y direction), and the rotary tool engages with the anvil 20 while the hammer 25 rotates, so that the rotary tool moves in the outer peripheral direction (M- It vibrates in the N direction), but contact 1 of relay 14
When the opening and closing directions of the contacts 6 and 17 coincide with this vibration direction, the opening and closing of the contacts 16 and 17 is affected by the vibration, and the relay 1
4 may malfunction. Therefore, the opening / closing direction of the contacts 16 and 17 is orthogonal to the XY direction as shown in FIG. 1, and the opening / closing direction of the contacts 16 and 17 is substantially the MN direction as shown in FIG. So that they are in orthogonal directions,
The arrangement direction of the relay 14 is set so that the opening / closing direction of the contacts of the relay 14 does not coincide with the vibration direction to prevent the relay 14 from malfunctioning due to vibration.

[0018]

[0019]

As described above, according to the present invention, a main body portion that houses a motor and a drive body portion that houses a drive shaft that is rotationally driven by the motor and that is disposed at the tip of the main body portion are substantially L-shaped. In a rotary tool with a housing formed in
If the tightening impact torque exceeds a certain level, the motor
Since the motor control section for stopping the rotation of the motor and limiting the torque and controlling the motor is provided between the main body section and the drive body section and the corner space section is arranged in the housing, the motor control section is Even if it protrudes from the inside, it will be stored in this entering corner space, the protruding part by the motor control part will not be an obstacle when working in a narrow place, and even if the power tool is dropped, the main body part and drive This protects the motor control unit from being directly hit by the body portion and can prevent a failure of the motor control unit. Also, by arranging the motor control section in this way, the height of the main body does not become high unlike the case where the motor control section is arranged below the motor, and the weight balance is not deteriorated. It can be prevented.

Further, the battery pack is attached to the rear end of the main body so as to protrude in the same direction as the drive main body, and is more than the line connecting the tip of the drive shaft protruding from the drive body and the protruding tip of the battery pack. Since the motor control unit is provided so as to be arranged on the body body side, the motor control unit is housed in the drive shaft protruding from the drive body unit, the concave space surrounded by the battery pack and the body body unit. In addition, the motor control unit is less likely to get in the way, and the motor control unit is further protected from three sides so that the motor control unit is less likely to directly hit when the electric tool is dropped.

Further, since the impact mechanism section is provided in the drive body section and the motor control section is formed with the relay, the relay is arranged so that the opening / closing direction of the contact of the relay does not coincide with the vibration direction of the impact mechanism section. , The opening and closing of contacts is no longer affected by vibration,
It is possible to prevent the relay from malfunctioning due to vibration.

[Brief description of drawings]

FIG. 1 is a partially cutaway front view of an embodiment of the present invention.

FIG. 2 is a side view in which a part of the same is cut away.

FIG. 3 is an enlarged cross-sectional view of a part of FIG.

FIG. 4 is a sectional view of a conventional example.

FIG. 5 shows another conventional example, and includes (a) and (b).
Is a schematic front view.

[Explanation of symbols]

1 motor 2 Main body 3 drive axis 4 Drive body 11 Impact mechanism section 13 Motor control unit 14 relays 16 contacts 17 contacts 27 housing 52 battery pack

Claims (2)

(57) [Claims] 1. A rotary tool in which a housing is formed in a substantially L-shape from a main body body portion that houses a motor and a drive body portion that houses a drive shaft that is rotationally driven by the motor and that is located at the tip of the main body body portion. , Tightening impact torque
When it exceeds a certain level, stop the rotation of the motor and increase the torque.
A motor control unit for controlling the motor to be limited is provided in the housing by being arranged in the entering corner space between the main body and the drive body, and is installed at the rear end of the main body in the same direction as the drive body.
Insert the battery pack so that it projects, and project it from the drive body.
The line connecting the tip of the drive shaft and the protruding tip of the battery pack
The above-mentioned motor control unit so that it is arranged on the body side of the main body
Rotary tool, characterized by comprising providing a. 2. An impact mechanism section is provided in the drive body section.
In addition, the motor controller is equipped with a relay to form a relay.
-The opening and closing direction of the contact is the vibration direction of the impact mechanism
The rotary tool according to claim 1 , wherein the relay is arranged so as not to coincide with the above .