JPH079356A - Nut runner - Google Patents

Abstract

PURPOSE:To provide a nut runner which can accurately align a socket with a bolt and a nut at low cost. CONSTITUTION:The output shaft 2 of a motor 1 is connected to socket 19 by a joint member composed of more than two knots, so that the socket 19 is made freely rocked in the direction perpendicularly intersected with an output shaft. The joint member is made up of one joint 14, and of two joint pins 15 and 20 and is made up of two joints, and of two ball joints.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to improvements in nut runners for tightening bolts and nuts.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 10, there has been proposed a nut runner NR3 for tightening bolts and nuts with a socket 3 connected to an output shaft 2 of a motor 1 (see Japanese Utility Model Publication No. 63-48388). Above nut runner N
R3 engages the connecting pin 4 of the output shaft 2 with the elongated hole 3a of the socket 3 to mount the socket 3 so as not to rotate and to move in the axial direction, and urge the spring 3 downward. .

Then, as shown in FIG. 11 (A), the bottom plate 6 with the nut runner NR set is lowered to fit the socket 3 into the bolt / nut 7,
The motor 1 is driven to rotate the socket 3 and tighten the bolts and nuts 7.

[0004]

However, it is good when the center alignment of the socket 3 and the bolt / nut 7 of the nut runner NR3 is accurate as shown by the one-dot chain line in FIG. Is difficult to align accurately, and as shown in FIG.
On the other hand, the socket 3 is often inserted obliquely, which causes a problem that the bolt / nut 7 is not tightened properly. In addition, vision sensor (video)
Although there is a method of aligning the socket 3 and the bolts / nuts 7 by checking their positions, the cost is high.

Therefore, an object of the present invention is to provide a nut runner capable of accurately aligning a socket with a bolt / nut and at a low cost.

[0006]

In order to achieve the above object, a nut runner according to claim 1 is a socket connected to an output shaft of a motor, and a nut runner for tightening bolts and nuts is used. The shaft and the socket are connected via a joint member having at least two joints capable of swinging the socket in a direction orthogonal to the axis.

Further, in the nut runner according to a second aspect of the present invention, the joint member is attached to the output shaft of the motor so as not to rotate and to move in the axial direction, the rear end portion of the joint and the output. A first joint pin that connects the tip of the shaft to allow the tip of the joint to swing in a direction orthogonal to the axis, and connects the tip of the joint and the rear end of the socket to the tip of the socket. And a second joint pin that can swing in the direction orthogonal to the axis.

In the nut runner according to a third aspect of the present invention, the joint member is a first joint attached to the output shaft of the motor so as to be non-rotatable and axially movable, and the first joint and the socket. And a second joint interposed between the second joint and the rear end of the second joint and the tip of the first joint so that the tip of the second joint can swing in the direction orthogonal to the axis. It comprises a first ball joint, a second ball joint that connects the tip end of the second joint and the rear end of the socket, and can swing the tip end of the socket in a direction orthogonal to the axis.

[0009]

According to the nut runner of the first aspect, the output shaft of the motor and the socket are connected to each other through the joint member having two or more joints so that the socket can swing in the direction orthogonal to the axis. The bolts and nuts can be accurately aligned with each other, and the tightening of the bolts and nuts does not occur, and the joint member can be manufactured at low cost.

When the joint member is composed of one joint and two joint pins as in the nut runner of the second aspect, the manufacturing cost can be reduced.

On the other hand, when the joint member is composed of two joints and two ball joints as in the nut runner of the third aspect, the swinging amount of the socket is increased and the allowable range of centering is expanded.

[0012]

The present invention will be described in detail below with reference to the embodiments shown in the drawings.

FIG. 1 shows the nut runner NR of the first embodiment.
It is a type that is vertically attached to the bottom plate 10 and tightens the bolts and nuts 7 from the vertical direction.

On the lower surface of the bottom plate 10 is a bolt 1
In the holding ring 12 fixed by 1, the output shaft 2 of the motor 1
The joint shaft 13 connected to is inserted vertically. The joint shaft 13 is the output shaft 2 of the motor 1.
May be one with.

As shown in detail in FIG. 4, the joint shaft 13 has a quadrangular insertion hole 13b into which the output shaft 2 of the motor 1 is inserted at the rear end portion 13a, and a spline on the outer periphery of the front end portion 13c. The shaft 13d is formed, and the tip portion 13c is formed.
Is provided with a pin hole 13e in a direction orthogonal to the axis.

As shown in detail in FIG. 3, the spline hole 1 that engages with the spline shaft 13d of the joint shaft 13 described above.
A joint 14 having a rear end 14b is provided.
When the spline hole 14a of the joint 14 is engaged with the spline shaft 13d of the joint shaft 13, the joint 14 is attached to the joint shaft 13 so as not to rotate and to move in the axial direction.

At the rear end portion 14b of the joint 14,
A pair of elongated holes 14c, 14c that are long in the axial direction are formed, and after the spline hole 14a is engaged with the joint shaft 13d, one elongated hole 14c passes through the pin hole 13e of the joint shaft 13d to the other elongated hole 14. When the first joint pin 15 (see FIG. 1) is inserted, the joint 14 is allowed to move in the axial direction with a stroke corresponding to the length of the elongated holes 14c, 14c with respect to the joint shaft 13 and is joined. .

As shown in FIG. 1, the joint shaft 13 is
A coil spring 16 is contracted to the outer periphery of the coil spring 16, the rear end of the coil spring 16 is abutted against the washer 17 on the lower surface of the holding ring 12, and the tip is the outer periphery of the rear end portion 14b of the joint 14. With the coil spring 16 biasing the joint 14 downward, the rear end of the elongated hole 14c has the rear end of the first joint pin 1
The movement is restricted by being hit by 5.

As shown in FIG. 3C, a predetermined gap t1 is provided between the spline shaft 13d of the joint shaft 13 and the spline hole 14a of the joint 14, and the tip of the joint 14 is formed by this gap t1. Part 14d
It swings around the first joint pin 15 in the direction orthogonal to the axis.

A spline shaft 14e is formed on the outer periphery of the tip portion 14d of the joint 14, and the tip portion 14d is formed.
Is provided with a pin hole 14f in the direction orthogonal to the axis, and a hemispherical recess 14g is formed on the tip surface.

As shown in detail in FIG. 2, the spline hole 19 that engages with the spline shaft 14e of the joint 14 is provided.
A socket 19 having a at the rear end portion 19b is provided. The spline hole 19a of the socket 19 is connected to the joint 1 described above.
4 is engaged with the spline shaft 14e, the joint 1
The socket 19 can be attached to the shaft 4 such that it cannot rotate but can move in the axial direction.

Pin holes 19c, 19c are formed in the rear end portion 19b of the socket 19 in a direction orthogonal to the axis, and after the spline hole 19a is engaged with the spline shaft 14e,
One pin hole 19c to the pin hole 14f of the joint 14
Through the other pin hole 19c into the second joint pin 20
When inserted (see FIG. 1), the socket 19 will be joined to the joint 14.

On the bottom surface of the spline hole 19a of the socket 19, the hemispherical recess 14 of the tip surface of the joint 14 is formed.
A hemispherical recess 19d is formed opposite to g.
By interposing the ball 21 (see FIG. 1) between 4g and 19d, the impact from the socket 19 side can be received by the ball 21 and the deformation of the second joint pin 20 can be prevented.

As shown in FIG. 2C, a predetermined gap t2 is provided between the spline shaft 14e of the joint 14 and the spline hole 19a of the socket 19, and the tip end portion of the socket 19 is formed by this gap t2. 19e swings about the second joint pin 20 in the direction orthogonal to the axis.

A fitting hole 19f into which the bolt / nut 7 is fitted is provided in the tip portion 19e of the socket 19.

According to the structure of the first embodiment, when the bottom plate 10 with the nut runner NR1 is lowered, the fitting hole 19f of the socket 19 is fitted into the bolt / nut 7, and then the motor 1 is driven. By rotating the socket 19 via the joint shaft 13 and the joint 14, the bolt / nut 7 can be tightened.

When the socket 19 and the bolt / nut 7 are eccentric (offset) when the fitting hole 19f of the socket 19 is fitted into the bolt / nut 7, the joint 14 is the first joint with respect to the joint shaft 13. The socket 19 swings around the pin 15 (first section), so that the socket 19 has the second joint pin 20 (second section) with respect to the joint 14.
Since it swings about, the socket 19 can be accurately aligned with the bolt / nut 7.

As a result, the socket 19 will not be inserted into the bolt / nut 7 from an oblique direction, and the bolt / nut 7 will not be defectively tightened. Further, basically, only the components such as the joint shaft 13, the joint 14, and the joint pins 15 and 20 are added, so that the manufacturing cost can be reduced.

FIG. 5 shows the nut runner NR of the second embodiment.
2 is a type that is horizontally attached to the bottom plate 30 and tightens the bolts and nuts 7 from the horizontal direction.

A bolt 3 is attached to the side surface of the bottom plate 30.
The joint shaft 32 is horizontally connected to the output shaft 2 of the motor 1 fixed by 1. The joint shaft 32 may be integrated with the output shaft 2 of the motor 1.

The joint shaft 32 has a square insertion hole 32b into which the output shaft 2 of the motor 1 is inserted at the rear end portion 32a.
And a square-shaped square shaft 32d on the outer periphery of the tip portion 32c.
Are formed.

As shown in detail in FIG. 9, a square insertion hole 33 that engages with the angular shaft 32d of the joint shaft 32 is provided.
A first joint 33 having a at the rear end portion 33b is provided. When the angular shaft 32d of the joint shaft 32 is engaged with the insertion hole 33a of the first joint 33, the first joint 33 is attached to the joint shaft 32 so as not to rotate and move in the axial direction.

As shown in FIG. 5, the joint shaft 32 is
A coil spring 34 is compressed around the outer periphery of the coil spring 34. The rear end of the coil spring 34 is abutted against a washer 35 fitted to the rear end portion 32a of the joint shaft 32, and the front end thereof is the first joint 33. The first joint 33 is pressed against a washer 36 fitted to the rear end portion 33b, and the coil spring 34 urges the first joint 33 forward (to the left in FIG. 5).

A joint guide plate 37 parallel to the bottom plate 30 is arranged in front of the bottom plate 30, and a guide ring 38 having a tapered hole 38a at the rear is arranged on the front surface of the joint guide plate 37. At the same time, a retaining ring 39 is arranged on the rear surface, and both rings 38, 39 are fixed by bolts 40.

Needle rollers 41 are arranged on the inner circumference of the holding ring 39, and the outer circumference of the rear side of the first joint 33 is rotatably supported by the needle rollers 41.

A hexagonal first ball joint 42 is integrally provided at the tip portion 33c of the first joint 33, and the first ball joint 42 is provided with a pin hole 42a in the direction orthogonal to the axis and the tip end. A hemispherical recess 42b is formed on the surface.

As shown in detail in FIG. 8, a second joint 44 having a hexagonal ball joint hole 44a at the rear end portion 44b into which the first ball joint 42 of the first joint 33 is fitted is provided.

As shown in FIG. 6A, the rear end portion 44b of the second joint 44 has a pin hole 44 extending in the direction orthogonal to the axis.
c, 44c are formed, and the first ball joint 42 is formed.
After being fitted into the ball joint hole 44a, the pin hole 42c of the first ball joint 42
Joint pin 45 to the other pin hole 44c through a
When the second joint 44 (see FIG. 5) is inserted, the second joint 44 is joined to the first joint 33. As a result, the tip portion 44f of the second joint 44 swings about the first joint pin 45 in the direction orthogonal to the axis.

As shown in FIG. 8C, a hemispherical recess 44d is formed on the bottom surface of the ball joint hole 44a of the second joint 44 so as to face the hemispherical recess 42b of the tip end surface of the first ball joint 42. , These both recesses 42
By interposing the ball 46 (see FIG. 5) between b and 44d, the impact on the second joint 44 side can be received by the ball 46 and the deformation of the joint pin 45 can be prevented.

A taper 44e that fits into the taper hole 38a of the guide ring 38 is provided on the outer periphery of the rear end portion 44b of the second joint 44. This taper 44
e, the first joint 33 is the coil spring 34
Is urged forward by the second joint 4
4 is also urged forward, and is fitted in the tapered hole 38a to restrict the movement of the first joint 33 and the second joint 44.

Further, the taper 44e is the taper hole 38a.
The second joint 44 is held in the horizontal position by being fitted into. That is, when the nut runner NR2 is a horizontal type, unless the second joint 44 is held in the horizontal position before the bolt / nut 7 is tightened, the second joint 44 swings downward due to its own weight, which will be described later. This is because the socket 48 cannot be fitted into the bolt / nut 7.

As shown in FIG. 8D, a hexagonal second ball joint 47 is integrally provided at the tip end portion 44f of the second joint 44, and the tip end face of the second ball joint 47 is formed. A bolt hole 47a is formed in the.

As shown in detail in FIG. 6, a socket 48 having a hexagonal ball joint hole 48a into which a second ball joint 47 of the second joint 44 is fitted is provided at a rear end portion 48b. The tip 48 of this socket 48
A fitting hole 48d into which the bolt / nut 7 is fitted is provided in c, and the fitting hole 48d and the ball joint hole 4 are provided.
It communicates with 8a through a communication hole 48e.

As shown in detail in FIG. 7, a taper bolt 49 having a tapered head portion 49a is provided, and the bolt portion 49b of the taper bolt 49 is passed from the fitting hole 48d of the socket 48 to the communication hole 48e, and When bolted to the bolt hole 47 a of the second ball joint 47, the socket 48 comes to be jointed to the second joint 44. Thereby, the tip portion 4 of the socket 48
8c swings in the direction orthogonal to the axis with the head 49a of the taper bolt 49 as a fulcrum.

As shown in FIG. 5, a coil spring 50 is contracted between the rear end portion 48b of the socket 48 and the tip end portion 44f of the second joint 44, and the urging force of the coil spring 50 causes the socket spring to be depressed. 48 will be held in a horizontal position.

With the configuration of the second embodiment, in the nut runner NR2, in the retracted position of FIG. 5, the taper 44e of the second joint 44 has the taper hole 3 of the guide ring 38.
The socket 48 is held in the horizontal position by being fitted into the 8a, and the socket 48 is held in the horizontal position by the biasing force of the coil spring 50.

Then, the bottom plate 30 with the nut runner NR2 set and the joint guide plate 37
Is advanced, the insertion hole 48d of the socket 48 is inserted into the bolt / nut 7, and when it is further advanced, the socket 48 is stopped by the bolt / nut 7 and does not move forward. Therefore, the taper 44e of the second joint 44 is The guide ring 38 is separated from the tapered hole 38a. In this state,
Since the socket 48 is fitted into and supported by the bolt / nut 7, the second joint 44 is held in the horizontal position. After that, when the motor 1 is driven, the joint shaft 32,
By rotating the socket 48 via the first joint 33 and the second joint 44, the bolts / nuts 7 can be tightened.

When the socket 48 and the bolt / nut 7 are eccentric (offset) when the socket / hole 48d of the socket 48 is fitted into the bolt / nut 7, the second joint 44 is positioned with respect to the first joint 33. Swing about the first ball joint 42 (first section) to move the socket 48
Oscillates around the second ball joint 47 (second joint) with respect to the second joint 44, so that the socket 48 can be accurately aligned with the bolt / nut 7.

As a result, the socket 48 is not fitted into the bolt / nut 7 from an oblique direction, and the bolt / nut 7 is not tightened badly. In addition, basically, only the components such as the joint shaft 32, the first joint 33, and the second joint 44 are added, so that the manufacturing cost can be reduced.

Further, since the first joint 33 and the second joint 44, and the second joint 44 and the socket 48 are connected by the ball joints 42 and 47, the swing amount becomes large and the allowable range of centering is expanded. .

[0051]

As is apparent from the above description, in the nut runner according to the first aspect, the output shaft of the motor and the socket are connected by a joint member having two or more joints, and the socket is oscillated in a direction orthogonal to the axis. Since it is movable, the centering of the bolts and nuts can be performed accurately, the tightening failure of the bolts and nuts does not occur, and the joint member can be manufactured at low cost.

If the joint member is composed of one joint and two joint pins as in the nut runner of the second aspect, the cost can be reduced.

On the other hand, when the joint member is composed of the two joints and the two ball joints as in the nut runner of the third aspect, the swing amount of the socket is increased and the allowable range of the centering is expanded. become.

[Brief description of drawings]

FIG. 1 is a side sectional view of a nut runner according to a first embodiment of the present invention.

2A is a front view, FIG. 2B is a side sectional view, and FIG. 2C is a rear view.

3A is a front view, FIG. 3B is a side sectional view, and FIG. 3C is a rear view.

FIG. 4 (A) of the joint shaft is a sectional side view of a main part,
(B) is a front view, (C) is a sectional view taken along line AA of (A),
(D) is a rear view.

FIG. 5 is a side sectional view of a nut runner of a second embodiment.

6A is a front view, FIG. 6B is a side sectional view, and FIG. 6C is a rear view.

7A is a front view and FIG. 7B is a side view of a taper bolt.

FIG. 8 is a rear view of (A) of the second joint, (B).
Is a front view, (C) is a cross-sectional side view of an essential part, and (D) is a cross-sectional side view of an essential part of the ball joint part.

9A is a front view of the first joint, FIG. 9B
Is a rear view, (C) is a cross-sectional side view of an essential part, and (D) is a cross-sectional side view of an essential part of the ball joint portion.

FIG. 10 is a side view of a conventional nut runner.

11 (A) and 11 (B) are side views of a bolt / nut tightening procedure.

[Explanation of symbols]

NR1, NR2 ... Nut runner, 1 ... Motor, 2 ... Output shaft, 7 ... Bolt / nut, 13 ... Joint shaft,
14 ... Joint, 15 ... First joint pin,
19 ... Socket, 20 ... Second joint pin, 32 ... Joint shaft, 33 ... First joint, 42 ... First ball joint, 44 ... Second joint, 47
… Second ball joint, 48… Socket.

Claims (3)

[Claims] 1. A socket connected to an output shaft of a motor,
A nut runner for tightening bolts and nuts, characterized in that the output shaft of the motor and a socket are connected via a joint member having at least two joints capable of swinging in a direction orthogonal to the axis. . 2. The joint member connects a joint attached to the output shaft of the motor so as to be non-rotatable and axially movable, and a rear end portion of the joint and a front end portion of the output shaft, A first joint pin capable of swinging the front end of the joint in the direction orthogonal to the axis, and a first joint pin capable of swinging the front end of the socket in the direction orthogonal to the axis by connecting the front end of the joint and the rear end of the socket. The nut runner according to claim 1, wherein the nut runner comprises two joint pins. 3. The joint member includes a first joint attached to the output shaft of the motor so as to be non-rotatable and axially movable, and a second joint provided between the first joint and the socket. A joint, a rear end of the second joint and a tip of the first joint, and a first ball joint capable of swinging the tip of the second joint in a direction orthogonal to the axis; and the second joint. The nut runner according to claim 1, comprising a second ball joint capable of connecting a front end portion of the socket and a rear end portion of the socket and swinging the front end portion of the socket in a direction orthogonal to an axis.