JPH09295278A - Nut runner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To tighten a nut strongly by screwing, while high speed rotating it with a low torque and seathing it on the seat surface quickly at the no load time, and converting the output shaft to a low speed and high torque by the load after seating, in the tightening time of the nut. SOLUTION: A sun gear 61 of a speed reduction part 6 consisting of a planet gear mechanism is formed on a first output shaft 45 connected to the rotor shaft 24 of an air motor 2 and also a bottomed cylinder body part 51 whose rear end surface is formed into a pressure receiving surface 52 is arranged around the first output shaft 45 rotatably. The internal gear 62 of the speed reduction part 6 is installed in this bottomed cylinder part 51 and the output shaft 65 of the speed reduction part 6 is connected integrally with the planet gear 63 meshed with the internal gear 62 and the sun gear 61. At the no load time of this output shaft 65 side, the bottomed cylinder body part 51 is rotated integrally with the first output shaft 45 by the friction force between a disc pad 54 arrange don the first output shaft 45 and the pressure receiving surface 52 of the bottomed cylinder body part 51 and the output shaft 65 of the speed reduction part 6 is rotated at a high speed. At a load time, a rotation torque of the opposite direction to the bottomed cylinder body part 51 is generated by overcoming the friction force and also the output shaft 65 is made in a rotation state with a low speed and high torque by making the bottomed cylinder body part 51 in a fixed state.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a nut runner for tightening or loosening a nut or a bolt head.

[0002]

2. Description of the Related Art Conventionally, a nut liner has been known as an automatic tightening tool for screws such as nuts and bolts. This nut runner is provided with a sun gear of a first reduction gear unit consisting of a planetary gear mechanism at the tip of the rotor shaft of an air motor, and the rotation speed of a first output shaft integrally connected to the planetary gear of the first reduction gear unit. The output torque of the third reduction gear unit by increasing the output torque by increasing the output torque of the third reduction gear unit by further connecting the second reduction gear unit and the third reduction gear unit, which also include the planetary gear mechanism, to the first reduction gear unit. A high torque is generated in the nut tightening socket body, and the nut is tightened by the torque.

[0003]

However, according to the nut runner as described above, the rotation speed of the air motor is set to the first to the third from the start of tightening the nut until the nut is seated and the tightening is completed. Since the nuts are tightened while sequentially decelerating by the speed reducing unit, there is a problem in that it takes a long working time until the nut with little load is seated and the working efficiency is reduced.

The present invention has been made in view of these problems, and an object thereof is to fasten the nut at a high speed when the nut is seated and when the load is low until the nut is seated. It is to provide a nut runner that can perform screw tightening work at low speed and high torque under high load.

[0005]

In order to achieve the above object, a nut runner of the present invention transmits rotation of a rotor shaft of a rotary drive source to an output shaft via a speed reduction unit composed of a planetary gear mechanism. In the configured nut runner, the internal gear of the planetary gear mechanism, which is the reduction gear unit, is configured to be rotatable, and the internal gear rotates the output shaft and the internal gear integrally when the output shaft side is unloaded, and when the load is loaded, the internal gear The present invention is characterized in that a clutch portion for decelerating and rotating the output shaft in a stopped state is provided.

In the nut runner, according to the invention described in claim 2, the rotation drive source is an air motor, and a planetary gear is formed by forming a gear at a front end portion of a rotor shaft of the air motor and fixing the gear to an internal gear. A sun gear of a first reduction gear unit consisting of a gear mechanism, while a gear is formed at the front end of a first output shaft integrally connected to the planetary gear of the first reduction gear unit, and the internal gear is rotatably provided. The sun gear of the second reduction gear unit including the planetary gear mechanism described above is provided, and the clutch portion is disposed on the rotatable internal gear and the planetary gear of the second reduction gear unit is connected to the output side for nut tightening. It is characterized by that.

A third aspect of the present invention is a concrete structure from the second speed reducer to the final output shaft. The second output shaft is integrated with the planetary gear of the second speed reducer including the planetary gear mechanism. And the gear formed at the front end portion of the second output shaft is used as a sun gear of a third reduction gear unit formed of a planetary gear mechanism to which an internal gear is fixed, and is integrally connected to the planet gear of the third reduction gear unit. A sun gear of a fourth reduction gear unit formed of a planetary gear mechanism in which a gear is formed at the front end portion of the third output shaft and an internal gear is fixed to the fourth gear, and the fourth gear is integrally connected to the planetary gear of the fourth reduction gear unit.
The nut tightening socket body is detachably attached to the front end portion of the output shaft.

Further, as the clutch portion, a rear end portion of the first reduction gear portion rotatable around the first output shaft is formed on the bottom portion, and an inner gear of the second reduction gear portion is formed on the inner peripheral surface of the front end portion. A bottomed cylindrical body portion is provided, and a pad shoe that rotates integrally with the first output shaft and is slidable in the length direction of the first output shaft is provided in the bottomed cylindrical body portion. A cylindrical member having a structure in which the shoe is pressed against the inner surface of the rear end portion of the bottomed cylindrical body portion by a spring force, and a concave arc surface is formed at a plurality of positions on the inner peripheral surface of the bottomed cylindrical body portion. A small ring-shaped member is fixed at a small interval, and a circular ring member, which rotatably holds rollers provided corresponding to each of the concave arc-shaped surfaces, is rotatably interposed in the small space portion in the circumferential direction, One of the concave arc-shaped surfaces of the roller can be obtained by rotating the circular ring member by an external operation so as to switch between left and right. It is configured to engaged with the state bite between the outer peripheral surface of the end portion and the bottomed cylindrical body portion.

[0009]

When the air motor is driven to rotate its rotor shaft in one direction, the output shaft of the speed reduction unit composed of the planetary gear mechanism rotates in the same direction. At this time, when the internal gear of the planetary gear mechanism is configured to rotate integrally with the sun gear when there is no load, the output shaft integral with the sun gear rotates at high speed to rotate the nut with low torque, Initial screw tightening is done quickly. On the other hand, when a load is generated on the output shaft side, the internal gear stops rotating, the output shaft rotates at low speed, and the screw is tightened with high torque.

That is, when the rotor shaft rotates, the output shaft of the first reduction gear unit, which is a planetary gear mechanism, rotates in the same direction, and the rotation of the output shaft changes. It is transmitted from the second reduction gear unit, which also includes the planetary gear mechanism, to the fourth reduction gear unit via the third reduction gear unit. At this time, the internal gear of the second reduction gear portion is formed on the inner peripheral surface of the front end portion of the bottomed tubular body portion which is one component of the clutch portion described in claim 4, and the bottomed tubular body portion is formed. Is rotatably arranged around the output shaft of the first reduction gear unit, rotates integrally with the output shaft in the bottomed cylindrical body portion, and is pressed against the inner surface of the rear end portion of the bottomed cylindrical body portion by a spring force. Since the pad shoe is provided, when the frictional force between the pad shoe and the bottomed tubular body is larger than the tightening torque of the nut, the output shaft of the first reduction gear unit and the bottomed tubular body are separated from each other. The nuts are screwed together by rotating integrally and transmitting the rotation of the output shaft of the first reduction gear to the third reduction gear side as it is without being decelerated by the second reduction gear and rotating at high speed in the same direction. It is a thing.

When the nut is seated, the tightening resistance (load) increases, and the load torque of the output shaft of the third reduction gear part also increases. At this time, if the output shaft of the second reduction gear unit tries to continue to drive further, the output gear of the second reduction gear unit is added to the internal gear provided in the bottomed cylindrical body portion via the planetary gear of the second reduction gear unit. Torque in the opposite direction is applied. When the torque in the opposite direction exceeds the frictional force between the pad shoe and the inner surface of the bottomed tubular portion, a slip occurs between the two and the internal gear tries to rotate in the opposite direction to the output shaft of the first reduction gear unit. By the rotation in the opposite direction, the roller arranged on the outer peripheral surface of the bottomed cylindrical body bites into one end of the arc-shaped surface provided on the inner surface of the fixed cylindrical member, and the bottomed cylindrical body cannot be rotated. To lock (lock).

Therefore, the planetary gear of the second reduction gear unit meshing with the sun gear formed at the front end of the output shaft of the first reduction gear unit rotates while meshing with the internal gear of the fixed bottomed cylindrical body unit,
The second deceleration portion exerts a deceleration action to tighten the nut at low speed and high torque through the third and fourth deceleration portions. Further, when loosening the nut, it is performed by rotating in the opposite direction to the above, and at that time, the roller arranged on the outer peripheral surface of the bottomed cylindrical body part is provided on the inner surface of the fixed cylindrical member. This bites into the other end of the arcuate surface to generate high torque.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described with reference to the drawings. An air motor 2 as a rotary drive source is arranged in the rear end of a cylindrical housing 1 and a nut (not shown) is provided at the front end. (3) The tightening socket body 3 is rotatably provided, and the air motor 2 and the socket body 3 are further provided.
Between the first and second speed reducing parts 4, 7 and 8 composed of a planetary gear mechanism, the clutch part 5, and the second, third, and fourth speed reducing parts 6, 7, and 8 composed of a planetary gear mechanism. The rotation torque is input to the first reduction gear unit 4, is output to the second to fourth reduction gear units via the clutch unit 5, and the rotation torque is transmitted to the socket body 3.

As is well known, the air motor 2 has a rotor 21.
A plurality of grooves are radially provided at regular intervals in the circumferential direction, and the blades 22 are inserted into and retracted from the grooves, and the tip end surface of the blades 22 is eccentric to the rotor 21. It is slid on 23 by air pressure or spring force. Further, a compressed air supply passage 12 is provided in a handle portion 11 fixed to the lower surface of the rear end portion of the housing 1, and an on-off valve for the passage.
13, an opening / closing operation lever 14, a compressed air passage 15 provided through the opening / closing valve 13, and an air motor communicating from the compressed air passage 15 to the air motor 2 side through a switching valve (not shown). A branch passage (not shown) is provided for rotating 2 in the clockwise and counterclockwise directions. Reference numeral 16 is an exhaust passage for the compressed air used to drive the rotation of the air motor 2.

A rotor shaft 24, which serves as an input shaft for the first speed reducer 4 side, is integrally projectingly provided at the center of the front surface of the rotor 21 of the air motor 2, and a front end portion of the rotor shaft 24 has a first end. The sun gear 41 of the first reduction gear unit 4 is formed. The first reduction gear unit 4 includes the sun gear 41, the fixed internal gear 42 fixed to the inner peripheral surface of the housing 1, the sun gear 41 and the fixed internal gear.
Two or three planetary gears 43 meshing with each other at an angular interval of 180 degrees or 120 degrees in the circumferential direction, a short shaft 44 rotatably supported at the center of the planetary gears 43, and a rear shaft Flange part at the end
A first output shaft 45 which is integrally provided with the flange portion 46, and in which a protruding portion of the short shaft 44 protruding from each planetary gear 43 is inserted into a hole formed in the flange portion 46 to rotate integrally with the planetary gear 43. It consists of

The clutch portion 5 has a bottomed cylindrical body portion 51 rotatably fitted on the first output shaft 45 via bearings 90 and 91, an intermediate portion of the first output shaft 45 and a bottomed cylinder. A disk-shaped spring receiver 53 slidably contacted between intermediate portions of the inner peripheral surface of the body portion 51 via a sealing material, and a disk pad 54 press-contacted to a vertical pressure-receiving surface 52 of the bottom portion of the bottomed tubular body portion 51. It consists of a pad shoe 55 and a spring 56 consisting of a disc spring press-fitted between the spring receiver 53 and the pad shoe 55. The pad shoe 55 is attached to the first output shaft 45 so as to be movable in the front-rear direction and integrally rotatable. Has been.

Further, as shown in FIG. 2, the clutch portion 5 is a circular ring member rotatably fitted on the outer peripheral surface of the bottomed cylindrical body portion 51.
5a, a cylindrical roller 5c movably held in the circumferential direction in holes 5b penetrating the circular ring member 5a at regular angular intervals in the circumferential direction, and integrally fixed to the inner circumferential surface of the housing 1. Then, the fixed cylindrical member 5d covering the outer peripheral surface of the circular ring member 5a, and the both ends provided at a plurality of inner peripheral surfaces of the fixed cylindrical member 5d corresponding to the respective rollers 5c are spherical locking surfaces 5f, 5g. Concave arc surface formed
5e, a ring-shaped switching member 5h rotatably fitted on the outer peripheral surface of the housing 1, and a connecting pin 5i made of a screw body integrally connecting the switching member 5h and the ring member 5a, The long hole 5j provided in the above-mentioned housing 1 and fixed cylindrical member 5d that enables the connecting pin 5i to reciprocate in the circumferential direction at a constant angle.
And

Then, when the circular ring member 5a is integrally rotated through the connecting pin 5i by the rotation operation of the switching member 5h, the roller 5c arranged in the hole 5b of the circular ring member 5a is moved. The outer peripheral surface of the bottomed cylindrical body portion 51 and the locking surface 5f of the concave arc surface 5e of the fixed cylindrical member 5d.
Alternatively, it is configured such that the bottomed cylindrical body portion 51 is prevented from rotating in the biting direction side by making it wedge-like into 5 g, and is freely rotatable in the opposite direction side.

The second speed reducer 6 is a first speed reducer of the first speed reducer 4.
The gear formed at the front end portion of the output shaft 45 is used as the sun gear 61, and the internal gear 62 is formed or provided on the inner peripheral surface of the front end expanded cylinder portion of the bottomed cylindrical body portion 51 of the clutch portion 5. 61
Two or three planetary gears 63 mesh with the inner gear 62 and the inner gear 62 at an angular interval of 180 degrees or 120 degrees in the circumferential direction, and a minor shaft 64 is rotatably supported at the center of each planetary gear 63. In addition, the second output shaft 65 is rotatably provided in front of the shaft center of the first output shaft 45, and each of the above-mentioned holes is formed in the hole formed in the flange portion 66 provided at the rear end of the second output shaft 65. Short shaft 64 protruding from the planetary gear 63
The second output shaft 65 is configured to rotate integrally with the planetary gear 63 by inserting the protruding portion of the above.

The third speed reducer 7 is the second speed reducer 6 of the second speed reducer 6.
The gear formed at the front end of the output shaft 65 is used as the sun gear 71, and the housing 1 on the outer peripheral side of the sun gear 71 is provided.
The internal gear 72 is fixed to the inner peripheral surface of the, and two or three planetary gears 73 are provided at an angular interval of 180 degrees or 120 degrees in the circumferential direction between the sun gear 71 and the fixed internal gear 72. The short shaft 74 is rotatably supported at the center of each planetary gear 73, and the third output shaft 75 is rotatably provided in front of the axis of the second output shaft 65. A short shaft 74 protruding from each planetary gear 73 is inserted into a hole formed in a flange portion 76 provided at the rear end.
The third output shaft 75 is configured to rotate integrally with the planetary gear 73 by inserting the protruding portion of the above.

Similarly, in the fourth reduction gear unit 8, the sun gear 81 is a gear formed at the front end of the third output shaft 75 of the third reduction gear unit 7.
In addition, an internal gear 82 is formed or fixed to the inner peripheral surface of the housing 1 on the outer peripheral side of the sun gear 81, and the sun gear 81 and the fixed internal gear 82 are circumferentially 180 degrees or
Two or three planetary gears 83 are engaged with each other with an angular interval of 120 degrees, a short shaft 84 is rotatably supported at the center of each planetary gear 83, and the axial center forward of the third output shaft 75. Rotatably provided with a fourth output shaft 85, and a protruding portion of the short shaft 84 protruding from each planetary gear 83 is provided in a hole formed in a flange portion 86 provided at a rear end of the fourth output shaft 85. Insert and fit the fourth output shaft 85
Is configured to rotate integrally with the planetary gear 83.

The output shaft 85 of the fourth speed reducer 8 reaches near the front end opening of the housing 1, and the socket body 3 is provided between the outer peripheral surface of the output shaft 85 and the inner peripheral surface of the opening of the housing 1.
There is a gap into which the latter half of the can be inserted. As is well known, the socket body 3 has a square hole (hexagonal hole) 31 for tightening a nut or bolt head formed on the inner peripheral surface of the front end portion thereof. Further, the inner peripheral surface of the rear end portion of the socket body 3 is connected to the output shaft.
It is configured to be detachably fitted to the outer peripheral surface of the front end portion of 85 so as to rotate integrally with the output shaft 85. The socket 3 and the output shaft 85 may be fitted to each other by spline fitting or square shaft and square hole fitting. In addition, the fourth speed reducer 8
The output shaft 85 may be configured so as to project forward from the front end of the housing 1.

Reference numeral 17 denotes an arm member having an upper end integrally fixed to the lower peripheral surface of the front end of the housing 1, and a short tubular body 19 having a hole 18 into which a nut can be fitted at the lower end thereof, which is integrated in the front-rear direction. The hole 18 of the short tubular body 19 is already fastened to the nut, or the nut fitted to the socket body 3 is fitted to another fixing member, and the fastening work is performed. It supports the reaction force on the side of the hanging 1 that occurs occasionally.

In order to tighten the nut with the nut runner thus constructed, first, the switching member 5h of the clutch portion 5 is operated to move the circular ring member 5a as shown in FIG. 2 in the nut tightening direction (clockwise direction). Rotate in the opposite direction to
By moving the roller 5c provided on the circular ring member 5a to one locking surface 5f side of the concave arcuate surface 5d provided on the inner surface of the fixed cylindrical member 5d, the bottomed cylindrical body portion 51 is clockwise. Is rotatable, but is prevented from rotating in the counterclockwise direction by engaging the roller 5c in the wedge-shaped space between the bottomed cylindrical body portion 51 and the locking surface 5f.

In this state, after the socket body 3 is fitted on the nut (not shown), compressed air is supplied to the air motor 2 to rotate the rotor shaft 24 of the air motor 2 clockwise. By the rotation of the front end sun gear 41 of the rotor shaft 24, the planetary gear 43 of the first reduction gear unit 4 revolves around the sun gear 41 while rotating around the sun gear 41, and the first output shaft 45 connected to the planetary gear 43 is decelerated by one stage. Transmits rotational speed and increased torque.

Further, the rotation of the output shaft 45 of the first reduction gear unit 4 is transmitted to the second, third, and fourth reduction gear units 6 to 8 and is fitted to the output shaft 85 of the fourth reduction gear unit 8 in the socket body. 3 is rotated clockwise to screw the nut in the tightening direction, but there is almost no load until the nut is seated on the seating surface, and the output shaft side of the second reduction gear unit 6 is Resistance that opposes the rotational torque of the output shaft 65 does not occur. On the other hand, the bottomed cylindrical body portion 51 of the clutch portion 5 having the internal gear 62 of the second reduction gear portion 6
, The disc pad 54 of the pad shoe 55 disposed on the output shaft side of the first speed reducer 4 is pressed against the pressure receiving surface 52 at the rear end thereof by the force of the spring 56. Output shaft of the first speed reducer 4 by force
45 and the bottomed cylindrical body portion 51 rotate integrally at the same rotation speed without slipping, and the sun gear 61 provided at the front end portion of the first output shaft 45 and the front end inner circumference of the bottomed cylindrical body portion 51. The planetary gear 43 of the second reduction gear unit 6 meshing with the internal gear 62 provided on the surface rotates integrally with the bottomed cylindrical body portion 51 without rotating, and the output shaft 65 of the second reduction gear unit 6 has the first reduction gear unit. It will rotate at the same speed as the output shaft 45 of No. 4 at a high speed.

The rotation of the output shaft 65 of the second speed reducer 6 is transmitted to the socket body 3 via the third and fourth speed reducers 7 and 8, and the socket body 3 is decelerated by the second speed reducer 6. The nut is rotated at a high speed, and the nut is rotated and screwed until it is seated on the seating surface.

When the nut is screwed and seated on the seating surface, a tightening resistance force (load) is applied to the output shafts of the second to fourth speed reducers to rotate these output shafts in opposite directions. When the output shaft continues to rotate clockwise further against the load torque, the bottomed tubular portion 51 is proportional to the magnitude of the load torque.
A torque in the opposite direction to the output shaft is applied from the planetary gear 63 of the second speed reducer 6 via the internal gear 62 provided to the bottomed tubular body 51. When the torque in the opposite direction exceeds the frictional force between the pad shoe pressed by the spring 56 and the pressure receiving surface 52 of the bottomed tubular body portion 51, a slip occurs between the two and the bottomed tubular body portion
51 tries to rotate in the opposite direction to the rotation direction of the output shaft 45 of the first reduction gear unit 4.

By the rotating action in the opposite direction, the bottomed cylindrical body portion
A roller 5c, which is rotatably held in a hole 5b of a circular ring member 5a arranged on the outer peripheral surface of 51, moves counterclockwise in FIG. 2 and is provided on the inner surface of the fixed cylindrical member 5d. Arc surface
It bites into one locking surface 5f of 5e to fix (lock) the bottomed cylindrical body portion 51 in a non-rotatable manner.

Therefore, the internal gear 62 of the second reduction gear portion 6 provided in the bottomed tubular body portion 51 becomes the same fixed internal gear as the third and fourth reduction gear portions 7 and 8, and the second reduction gear portion 6 The planetary gear 63 revolves around the sun gear 61 formed at the front end of the output shaft 45 of the first reduction gear unit 4 while rotating around the sun gear 61, and the output shaft 65 of the second reduction gear unit integrated with the planetary gear 63 has a low speed. 3rd with high torque
It will be output to the deceleration unit 7 side. Therefore, the rotation of the air motor 2 is transmitted as low speed and high torque to the output shaft of the fourth speed reducer 8 having the socket body 3 attached thereto through the first to fourth speed reducers, and the nut is firmly seated on the seating surface. It is something to wear.

Next, when loosening the seated nut,
By operating the switching member 5h of the clutch portion 5, the circular ring member 5a is moved to the position shown in FIG.
As shown in FIG. 5, by rotating the nut 5c in the direction opposite to that when the nut is tightened, the roller 5c is provided on the inner surface of the fixed cylindrical member 5d. Leave it in a state where it bites into the wedge-shaped space between the outer peripheral surface of 51.

In this state, when compressed air is supplied to the air motor 2 to rotate the rotor shaft 24 in the counterclockwise direction, the load (resistance torque) on the seated side of the nut is seated in the initial stage of loosening the nut. A clockwise rotation torque is generated in the bottomed cylindrical body portion 51, and the roller 5c overcomes the frictional force between the pad shoe 55 and the pressure receiving surface 52 of the bottomed cylindrical body portion 51 to lock the other end of the concave arc surface 5e. The bottomed cylindrical body portion 51 becomes non-rotatable by biting into the surface 5g, and thus, similarly to the above, the output shaft of the second reduction portion 6
65 becomes a low speed and high torque, and the nut can be loosened with a strong torque through the third and fourth speed reducers.

When the nut moves away from the seating surface, there is almost no load. Therefore, the bottomed cylindrical body portion 51 rotates integrally with the output shaft 45 of the first reduction gear portion 4 and the second reduction gear portion 6 decelerates. The output shaft 65 rotates at high speed without any action,
The work of loosening the nut is quickly performed via the fourth speed reducer.

In the above embodiment, the third reduction gear unit 7 and the fourth reduction gear unit 8 are sequentially connected to the second reduction gear unit 6 having the bottomed cylindrical body portion 51, but the fourth reduction gear unit is used. 8 may be eliminated and the socket body 3 may be mounted on the output shaft 75 of the third reduction gear unit 7, or the second and third reduction gear units may be eliminated.
The socket body 3 may be attached to the output shaft 65 of the speed reducer 6.

[0035]

As described above, according to the nut runner of the present invention, in the nut runner configured to transmit the rotation of the rotor shaft of the rotary drive source to the output shaft via the speed reducing unit including the planetary gear mechanism, When the output shaft is unloaded, the output shaft and the internal gear rotate integrally, and when the output shaft is loaded, the rotation of the internal gear is stopped and the output shaft is decelerated and rotated. In addition, the output shaft can be rotated at high speed with low torque until the screw is seated, and when the load increases due to seating, the output shaft can be screwed at low speed and high torque. Therefore, the screw tightening work can be performed efficiently and reliably.

[Brief description of drawings]

[Fig. 1] Vertical side view of the nut runner,

FIG. 2 is a vertical sectional front view showing a switching structure of a clutch unit,

FIG. 3 is a vertical cross-sectional front view showing a state of switching to the opposite direction.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Housing 2 Air motor 3 Socket body 4 1st reduction part 5 Clutch part 6 2nd reduction part 7 3rd reduction part 8 4th reduction part 51 Bottomed cylindrical part 62 Internal gear of the 2nd reduction part

Claims (4)

[Claims] 1. A nut runner configured to transmit the rotation of a rotor shaft of a rotary drive source to an output shaft via a speed reduction unit composed of a planetary gear mechanism, wherein an internal gear of the planetary gear mechanism serving as a speed reduction unit is rotatable. And the internal gear,
A nut runner, wherein the output shaft side and the internal gear are integrally rotated when there is no load on the output shaft side, and when the load is present, a clutch portion is provided for decelerating the output shaft by stopping the rotation of the internal gear. 2. A rotary drive source is an air motor, and a sun gear of a first reduction gear unit comprising a planetary gear mechanism in which a gear is formed at a front end portion of a rotor shaft of the air motor and an internal gear fixes the gear. On the other hand, a gear is formed at the front end of the first output shaft that is integrally connected to the planetary gear of the first reduction gear unit, and this gear has a second reduction gear unit formed of a planetary gear mechanism in which an internal gear is rotatably provided. The nut runner according to claim 1, wherein the nut gear is a sun gear, and the clutch portion is disposed on the rotatable internal gear and the planetary gear of the second reduction gear portion is connected to the output side for nut tightening. . 3. A planetary gear in which a second output shaft is integrally connected to a planetary gear of a second reduction gear unit including the planetary gear mechanism, and a gear formed at a front end portion of the second output shaft is fixed to an internal gear. A planetary gear mechanism in which a sun gear of a third reduction gear unit formed of a mechanism is formed, and a gear is formed at a front end portion of a third output shaft integrally connected to the planetary gear of the third reduction gear unit, and the gear is fixed to an internal gear. And a nut tightening socket body is detachably attached to a front end portion of a fourth output shaft integrally connected to the planetary gear of the fourth reduction gear unit. The nut runner according to claim 1 or claim 2. 4. The clutch portion has a rear end portion, which is rotatable around the first output shaft of the first reduction gear portion, formed on the bottom portion, and an internal gear of the second reduction gear portion formed on the inner peripheral surface of the front end portion. A bottomed cylindrical body portion is provided, and a pad shoe that rotates integrally with the first output shaft and is slidable in the length direction of the first output shaft is provided in the bottomed cylindrical body portion. A cylindrical member having a structure in which it is pressed against the inner surface of the rear end of the bottomed cylindrical body portion by a spring force and concave arcuate surfaces are formed at a plurality of locations on the inner peripheral surface of the bottomed cylindrical body portion. Fix at intervals
A circular ring member, which rotatably holds rollers provided corresponding to each of the concave arc surfaces, is rotatably interposed in the circumferential direction in the small interval portion, and the circular ring member is switched to the left or right by an external operation. 5. The roller is configured so as to be locked in a state of biting between one end of the concave arc surface and the outer peripheral surface of the bottomed cylindrical body portion by rotating the roller. Nut runner.