JPH0453635A - Bolt-nut clamper - Google Patents

Abstract

PURPOSE:To secure such a bolt-nut clamper that is large in a relative shiftable valve between a socket and a driven member and they are kept in a concentric state at freedom, by connecting the socket and the driven member through an intermediate transmission shaft and two sets of coupling and shaft alignment device. CONSTITUTION:Preload is given to both compression coil springs 66, 77, and taper surfaces 62 and 64 as well as taper surfaces 72 and 74 are all kept in an engaging state, whereby a driven member 10, an intermediate transmission shaft 12 and a socket 14 are concentrically positioned by both coupling and shaft alignment devices 68, 81, while a pin 110 is engaged with two slots 114, 116, keeping a holding sleeve 82 and both engaging holes 88, 86 of the socket 14 in the same phase. If a piston 122 advances forward in a state of being inserted into the engaging holes 86, 88, the pin 110 goes forward and a rotary sleeve 92, rotating the holding sleeve 82, so that a nut is firmly held. A joint 24 couples the driven member 10 and the intermediate transmission shaft 12 rotatably around one point and relatively shiftable in the axial direction, and another joint 26 couples the transmission shaft 12 and the socket 14 as well.

Description

DETAILED DESCRIPTION OF THE INVENTION FIELD OF INDUSTRIAL APPLICATION The present invention relates to a bolt/nut tightening device for tightening bolts or nuts using power, and particularly relates to improved usability.

BACKGROUND ART A bolt/nut tightening device for tightening bolts or nuts using power is widely known, and the present applicant has also developed this type of bolt/nut tightening device and filed Utility Application No. 1-57333.
The application is currently being filed as a No. This device consists of a socket that is engaged with the head of a bolt or a nut (hereinafter referred to as the nut, etc.), a driven member that is engaged with the drive shaft of a rotary drive device, and a rotation of the socket and the driven member. and a coupling device capable of transmitting torque and capable of constant relative movement.

According to this device, even if the axis of the nut or the like to be tightened does not coincide with the axis of the driven member, the nut or the like can be tightened, and the tightening work can be easily performed.

Problems to be Solved by the Invention However, in this device, the degree of freedom of the coupling device is still not sufficient, and therefore, if there is a large deviation of the axis of the socket with respect to the axis of the driven member, the tightening operation is not necessary. There was a problem that it could not be done properly.

Further, the above-mentioned coupling device allows relative movement between the socket and the driven member when tightening a nut, etc., but normally it is equipped with an elastic member that serves to align the axes of the socket and the driven member. However, there was a problem in that the axis alignment function was not yet sufficient. Since the elastic member undergoes deformation that is approximately proportional to the load, when the bolt/nut tightening device is used in a horizontal position where the load applied to the elastic member is maximum based on the weight of the component, In a free state where no force is applied to the socket, the tip of the bolt/nut tightening device bends downward due to its own weight, making it possible to press the nut, etc. held by the socket against the mating bolt, etc. in an appropriate posture. This caused the problem that the tightening work was difficult.

The present invention provides a bolt/nut tightening device that allows relative movement between the socket and the driven member to be larger than conventional ones, but in which the socket and the driven member are reliably maintained in a coaxial state in a free state. This was done with the goal of obtaining it.

Means for Solving the Problems In order to solve the above problems, a bolt/nut tightening device according to the present invention includes a socket that is engaged with a nut, etc., and a driven member that is engaged with a drive shaft of a rotary drive device. and an intermediate transmission shaft that transmits the rotation of the driven member to the socket, and the socket and the intermediate transmission shaft, and the intermediate transmission shaft and the driven member are connected to each other as connected members by one set of connection and alignment devices. , and each of these sets of connection/alignment devices (a) connects the connected members to each other so as to be capable of transmitting rotational torque and to be rotatable in all directions around approximately one point at least within a certain angular range; a joint; (c) a first engagement member and a second engagement member each having a first engagement surface and a second engagement surface that coaxially position the connected members by engaging with each other; and a biasing means for biasing the first and second engagement members in a direction in which the first and second engagement surfaces engage with each other.

Function In the bolt/nut tightening device configured as described above, the socket and the driven member are connected by the intermediate transmission shaft and two sets of coupling/alignment devices, so that the socket is connected to the driven member in the radial direction (driven relative movement (direction perpendicular to the axis of the member) is permitted by rotation of the intermediate transmission shaft, and
The orientation of the socket can be changed by rotating the socket with respect to the intermediate transmission shaft. In other words, compared to the bolt/nut tightening device described above, it is easier to increase the relative movable amount of the socket with respect to the driven member (the relative movable amount in the radial direction and the relative rotatable amount), and especially When the intermediate transmission shaft is lengthened, the relative movable amount of the socket in the radial direction with respect to the driven member can be increased even if the rotation angle allowed by the coupling/alignment device is small.

Moreover, in the free state, the first engagement surface and the second engagement surface are engaged by the biasing force of the biasing means to position the connected members coaxially, so that the driven member, the intermediate transmission shaft The socket is located in a straight line and will not bend downward even when the bolt/nut tightening device is used in a horizontal position. The positioning of connected members is
Since this is done by the engagement between the first engagement surface and the second engagement surface, the biasing force of the biasing means is applied between the first engagement surface and the second engagement surface even when the bolt/nut tightening device is in a horizontal position. If the size is set so that the engagement surface does not separate, the bolt/nut tightening device can be kept in a straight line.

Effects of the Invention As described above, according to the present invention, the relative movable amount of the socket to the driven member in the bolt/nut tightening device can be increased. Even if there is a large deviation in position or direction from the rotating/driving device, nuts etc. can be properly tightened. Moreover, in the free state, the bolt/nut tightening device is kept in a straight line, so it is easy to press the nut or the like against the device to be tightened in an appropriate posture.

Therefore, the work of tightening nuts and the like becomes easier, and the effect of improving work efficiency can be obtained. In particular, when the rotational drive device is held by a robot or the like and the tightening work is performed automatically,
If the rotary drive device is positioned at a constant position, the socket will also be accurately positioned at a constant position, making it easier to control the robot.

Furthermore, even when the axis of the nut or the like is considerably inclined with respect to the axis of the driven member, the tightening operation can be performed without any problem.

EXAMPLE Hereinafter, an example of the present invention will be described in detail based on the drawings.

As is clear from FIGS. 1 and 2, this bolt/nut tightening device has a driven member 10. An intermediate transmission shaft 12 and a socket 14 are provided. The driven member IO is a member that is connected to a drive shaft 18 of a rotary drive device 16 operated by air or electric power so as to be capable of transmitting rotational torque.

The driven member 10 is engaged with an engagement recess 22 of the intermediate transmission shaft 12 by an engagement protrusion 20 at the tip. The engaging recess 22 has a hexagonal cross-sectional shape, and the engaging protrusion 20 also has a hexagonal cross-sectional shape at the center in the axial direction and can transmit rotational torque. The outer peripheral surfaces of both ends of the mating projection 20 in the axial direction are spherical, so that the axes of the intermediate transmission shaft 12 and the driven member 10 can rotate relative to each other within a certain angular range around the center of the spherical surface. be. Engagement protrusion 2
0 and an engagement recess 22, the joint 2 connects the driven member 10 and the intermediate transmission shaft 12 so as to be rotatable around one point.
It consists of 4. Note that the engagement protrusion 20 and the engagement recess 22 are also movable relative to each other in the axial direction within a range in which the engagement protrusion 20 does not separate from the engagement recess 22.

The intermediate transmission shaft 12 and the socket 14 are connected by a joint 26 that is separate from the socket 14 so that rotational torque can be transmitted and the shaft can rotate relative to each other within a certain angular range. The joint 26 includes a joint member 28 shown in FIGS. 3 and 4. The joint member 28 is generally a cylindrical member with a bottom, and has a through hole 30 and a rectangular groove 32 at the bottom, and two rectangular protrusions 3 at the opposite end.
It is equipped with 4. In the rectangular groove 32, a rectangular projection 36 (see FIG. 1) formed on the end surface of the intermediate transmission shaft 12 is fitted, while in the rectangular projection 34, the socket 14 is fitted.
By fitting into the rectangular groove 38, the intermediate transmission shaft 12 and the socket 14 are connected so that rotational torque can be transmitted. By sliding both groove wall surfaces of the rectangular groove 32 and both side surfaces of the rectangular protrusion 36, the joint member 28 is movable relative to the intermediate transmission shaft 12 in the longitudinal direction of the rectangular groove 32, and also moves parallel to the groove wall surface. Relative rotation within a plane is possible. Also,
The socket 14 has both groove wall surfaces of the rectangular groove 38 and the rectangular protrusion 34.
It is possible to move relatively in the longitudinal direction of the rectangular groove 38 by sliding with both side surfaces of the rectangular groove 38, and to rotate relative to each other within a plane parallel to the side wall surface of the rectangular groove 38.

Moreover, since the rectangular groove 32 and the rectangular groove 38 are formed to intersect with each other at right angles, the socket) 1
4 is rotatable in all directions around one point with respect to the intermediate transmission shaft 12 within a certain angular range (within a range in which the rectangular groove 32.38 and the rectangular protrusion 36.34 do not separate in the axial direction), and , within a certain distance range in all directions within a plane perpendicular to the axis of the intermediate transmission shaft 12 (the rectangular protrusion 34 and the rectangular groove 3
8 does not separate in the radial direction and the inner circumferential surface of the through hole 30 does not come into contact with the outer circumferential surface of a guide 70 (described later)). Further, the socket 14 and the intermediate transmission shaft 12 are also movable relative to each other in the axial direction within a range in which the rectangular groove 32.38 and the rectangular protrusion 36.34 do not separate in the axial direction.

The driven member 10 is rotatably supported by a device main body 42 via two bearings 40. Although the device main body 42 is divided into a first member 43 and a second member 44 for manufacturing reasons, they act as an integrated member after assembly. The rotation drive device 16 is fixed to this device main body 42 .

The device main body 42 is positioned by a key 45, fixed to the tip of a robot arm (not shown), and can be moved to an arbitrary position.

A housing 50 is rotatably attached to the intermediate transmission shaft 12 via hair rings 46 and 48. For manufacturing reasons, the housing 50 has a first member 52. Although it is divided into a second member 54 and a third member 56, they function as an integrated member after assembly. The housing 50 is connected to the device main body 42 by a spherical bearing 58. The spherical bearing 58 is slidably fitted to the outer peripheral surface of the second member 44 of the device main body 42, and the housing 50 is fitted to the outer peripheral surface of the second member 44 of the device main body 42.
It is possible to rotate in all directions around one point (the spherical center of the spherical bearing 5) and to move relative to it in the axial direction.

A plurality of guides 6 are provided on the first member 52 of the housing 50 on one circumference centered on the axis of the housing 50.
0 are vertically arranged at equal angular intervals, and the tapered surface 62 of the head thereof is fitted into the tapered surface 64 of a tapered hole formed in the second member 44 of the device main body 42. A compression coil spring 66 is disposed on the outside of each guide 60 and biases the housing 50 and the device main body 42 in a direction that separates them from each other.
By engaging the tapered surface 64 of the housing 50
This prevents the device main body 42 from being separated beyond a certain limit. Furthermore, when the tapered surfaces 62 and 64 are engaged, the housing 50 and the device main body 42 are positioned coaxially. However, if a force above a certain level is applied to the housing 50, the compression coil spring 66 is compressed as the spherical bearing 58 moves relative to the second member 44 in the axial direction, and the engagement between the tapered surfaces 62 and 64 is released. As a result, the housing 50 can rotate in any direction within a certain angular range around the spherical center of the spherical bearing 58 relative to the device main body 42. Note that since the separation limit between the housing 50 and the device main body 42 is defined by the engagement of the tapered surfaces 62 and 64, the engagement protrusion 20 of the joint 24 is also prevented from detaching from the engagement recess 22.

As is clear from the above description, the tapered surfaces 62 and 64 function as a first engagement surface and a second engagement surface that engage with each other and position the driven member IO and the intermediate transmission shaft 12 coaxially. , the compression coil spring 66 has a tapered surface 62.6
4 in the direction of engagement with each other. The guide 60 and device main body 42 having these tapered surfaces 62 and 64, and the compression coil spring 6
6 is connected to the coupling/alignment device 6 in cooperation with the joint 24.
8.

On the other hand, the alignment between the intermediate transmission shaft 12 and the socket 14 is as follows:
Tapered surface 72 of guide 70 and tapered surface 7 of socket 14
This is done by engagement with 4. The guide 70 passes through the joint member 28 and is coaxially fixed to the distal end surface of the intermediate transmission shaft 12 by a bolt 76, and the joint member 28 and the socket 14 are biased away from each other by a compression coil spring 77. By doing so, the tapered surface 72.74
are engaged, and the socket 14 is positioned coaxially with respect to the intermediate transmission shaft 12. Moreover, the tapered surface is 72.7
4 engages, the annular protrusion 78 of the guide 70 is guided by the guide surface 79 to fit with the annular protrusion 80 of the socket 14, so that the socket 14 and the intermediate transmission shaft 1
2 is positioned coaxially with even greater accuracy. Note that the elastic force applied to the joint member 28 by the compression coil spring jig 77 is caused by the rectangular protrusion 36 of the intermediate transmission shaft 12
It is received by coming into contact with the bottom surface of the rectangular groove 32 of No. 8.

In this way, in the free state, the socket 14 and the intermediate transmission shaft 12 are positioned coaxially, but
If a force above a certain level is applied to the socket 14, the compression coil spring 77 is compressed and deformed, the tapered surfaces 74 and 72 are separated, and the annular projections 80 and 78 are disengaged, causing the socket 14 is the intermediate transmission shaft 12
It becomes possible to move and rotate relative to each other in the radial direction.

As is clear from the above description, the tapered surfaces 72 and 74 function as a first engagement surface and a second engagement surface for coaxially positioning the intermediate transmission shaft 12 and the socket 14 by engaging each other, and the compression coil Spring 77 has both tapered surfaces 72.74
It functions as a biasing means for engaging. The guide 70 having tapered surfaces 72, 74, the socket 14, and the compression coil spring 77 together with the joint 26 constitute a coupling/alignment device 81.

A gripping sleeve 82 is fitted on the outside of the socket 14,
A removal prevention member 84 prevents removal. The pull-out prevention member 84 is fixed in a state protruding from the outer circumferential surface of the socket 1-14, and as is clear from FIG.
5 to prevent the gripping sleeve 82 from being pulled out while allowing rotation within a certain angular range. Gripping sleeve 8
2 is provided with a fitting hole 88 having the same shape and dimensions as the fitting hole 86 into which the nut etc. of the socket 14 is fitted, and after the nut etc. is fitted into the re-fitting holes 86, 8B which are in the same phase. By rotating the gripping sleeve 82 relative to the socket 14, the phases of the refitting holes 86 and 88 are shifted, and a nut or the like is firmly gripped.

A sleeve rotating device 90 that rotates the gripping sleeve 82 for gripping a second nut, etc. includes a rotating sleeve 92 fitted on the outside of the intermediate transmission shaft 12, and a rotating sleeve 92 fitted on the outside of the intermediate transmission shaft 12.
A joint 94 connects the rotary sleeve 92 to the gripping sleeve 82, and a rotary drive device 96 rotates the rotary sleeve 92.

The joint 94 has substantially the same configuration as the joint 26, including a joint member 97, and includes a gripping sleeve 82 and a rotating sleeve 92.
and are connected to each other so that rotational torque can be transmitted, relative movement is possible in the axial direction, and relative rotation is possible. Further, the rotating sleeve 92 is coupled to the intermediate transmission shaft 12 by a pin 98 so as to be relatively rotatable and axially immovable. pin 98
extends through the intermediate transmission shaft 12 in the diametrical direction, and both ends protruding from the intermediate transmission shaft 12 are engaged with two elongated holes 100 formed long in the circumferential direction in the rotating sleeve 92. be. Notches are formed at both ends of the pin 98 protruding from the rotating sleeve 92, and an annular spring retainer 102 is engaged with the notches to prevent the pin 98 from being pulled out. This spring retainer 102
A compression coil spring 106 is disposed between the rotary sleeve 92 and an annular spring retainer 104 slidably fitted to the outer peripheral surface of the rotating sleeve 92 . Spring retainer 1
04 is fitted into a bearing retaining ring 108, and the bearing retaining ring 108 supports the pin 110. The pin 110 extends along one diameter of the bearing retaining ring 108 and has both ends connected to the bearing retaining ring 1.
08, and a U-shaped notch 112 of the spring retainer 104 is engaged with the end protruding from the spring retainer 104. A pair of elongated holes 114 and 116 are formed in each of the intermediate transmission shaft 12 and the rotating sleeve 92, and the pin 110 extends through these elongated holes 114 and 116. The elongated hole 114 is formed parallel to the axial direction, but the elongated hole 116 is formed inclined at a certain angle with respect to the axial direction, so that the pin 110 moves in the axial direction together with the spring retainer lO4 and the bearing retaining ring 108. At this time, the rotating sleeve 92 is rotated by an angle corresponding to the inclination angle of the elongate 116.

A ring 120 is fitted on the outside of the bearing 118 held by the outer peripheral surface of the bearing retaining ring 108, and a piston 122 is disposed opposite the ring 120. The piston 122 has a generally cylindrical shape and has a large diameter portion 124 at the rear end, and this large diameter portion 124 connects to the cylinder 126 fixed to the housing 50.
At the same time, the tip of the piston 122 projects outward from the cylinder 126, and this projecting end faces the ring 120. By fitting the piston 120 into the cylinder 126, the space inside the cylinder 126 is divided into two pressure chambers 128, 130.
Compressed air is selectively supplied to these pressure chambers 128 and 130 from ports 132 and 134, respectively, to move the piston 122 forward and backward. As piston 122 advances, it abuts ring 120 and moves pin 110 axially through bearing 118 and bearing retaining ring 108. When the viston 122 is retracted, the compression coil spring 106 retracts the bin 110 via the spring retainer 104 and bearing retaining ring 108. As the bin 110 moves forward and backward, the rotating sleeve 92 and the gripping sleeve 82 are rotated as described above.
The fitting holes 86 and 88 are in the same phase, allowing a nut or the like to be fitted into them, and as the piston 122 advances and the bottle 110 is advanced, the fitting holes 86 and 88 are out of phase. Fitting hole 8 so as to hold a nut etc.
A relative phase of 6,88 is determined.

The device main body 42 is provided with a spacing device 140 that stops the driven member 10 at a constant rotational phase, thereby stopping the socket 14 at a constant rotational phase. The driven member 10 is integrally provided with a cam 142 shown in FIG. 5, while a stopper member 144 is fitted to the device main body 42 so as to be slidable in the radial direction. an active position where the cylinder 146 engages with the cam 142, and a non-active position where the cylinder 146 disengages from the cam 142;
It can be moved to an intermediate position between these two positions. When the cam 142 rotates in the counterclockwise direction in FIG.
and an engagement groove 150 located on the same plane.

Therefore, after the engaging surface 148 comes into contact with the stopper member 144 and the driven member 10 stops, the stopper member 144
When the stopper member 144 is moved to the operating position, the stopper member 144 reliably fits into the engagement groove 150 and becomes in a state of preventing rotation of the driven member in both forward and reverse directions.

Next, the operation of the present bolt/nut tightening device will be explained using an example of tightening a nut onto a stud bolt.

Usually, the driven member 10. The intermediate transmission shaft 12 and the socket 14 are coaxially positioned by the coupling/alignment device 68, 81, and are maintained coaxially even if the entire bolt/nut tightening device is placed in a horizontal position. The compression coil springs 66.77 are preloaded to such a magnitude that the tapered surfaces 62, 64. Tapered surface 7
2 and 74 are kept in an engaged state.

Further, the piston 122 is at the rearward end position, and the bin 110
are engaged with the rear ends of the elongated holes 114 and 116, and the gripping sleeve 8
The fitting hole 88 of No. 2 and the fitting hole 86 of the socket 14 are kept in the same phase.

Therefore, when the robot is operated and a nut is supplied from the nut supply device with the socket 14 facing the nut supply device, the nut just fits into the fitting holes 86, 8B.

When the piston 122 moves forward in this state, it comes into contact with the ring 120 , and the bottle 110 is moved forward via the bearing 118 and the bearing retaining ring 108 , and the rotating sleeve 92 rotates accordingly, holding the gripping sleeve 82 via the joint 94 . Rotate.

As a result, the relative phase of the fitting hole 88 with respect to the fitting hole 86 changes, and the nut is firmly gripped.

Subsequently, the robot moves the socket 14 away from the nut supply device and approaches the stud bolt 152, as shown in FIG. At this time, even if the stud bolt 152 is tilted to some extent and there is some deviation between the socket 14 and the nut 154 gripped by the gripping sleeve 82, if the nut 154 is strongly (pressed) against the stud bolt 152, As shown in FIG. 7, the nut 154 is connected to the guide portion 15 of the stud bolt 152.
6, thereby placing the nut 154 and socket 14 in a coaxial position with respect to the stud bolt 152. At this time, the socket 14 moves a considerable amount in the radial direction and rotates by a considerable angle.
By bending at two places, 8 and the connection/alignment device 81, it is easily allowed.

Thereafter, when the rotational drive device 16 is activated and the socket 14 is rotated, the nut 154 is inserted into the stud bolt 15.
2 and tightened as shown in FIG.

In this embodiment, the joint 24 connects the driven member 10 and the intermediate transmission shaft 12 so that they are not only rotatable around one point but also movable relative to each other in the axial direction, In addition, the joint 26 also connects the intermediate transmission shaft 12 and the socket 1.
4 are connected in the same way. Then, due to the axial movement of the driven member 10 and the intermediate transmission shaft 12,
The compression coil spring 66 engages the tapered surfaces 62 and 64, and the relative movement in the axial direction between the intermediate transmission shaft 12 and the socket 14 causes the compression coil spring 77 to engage the tapered surfaces 72 and 74. ing. The joint 26 also allows relative movement in the radial direction between the socket 14 and the intermediate transmission shaft 12.

This is desirable but not essential;
It is also possible to connect the driven member 10 and the intermediate transmission shaft 12, or the intermediate transmission shaft 12 and the socket 14, using a joint that allows only rotation around a point such as a universal joint. However, in that case, it is necessary to change the mechanism for performing axis alignment.

An example thereof is shown in FIG. The guide 160 corresponds to the guide 60 in the above embodiment, and is attached to the first member 52 by a bolt 162 so as to be movable in the axial direction, and is also supported by a compression coil spring 164.
It is biased towards the 2nd side. The preload of the compression coil spring 164 is greater than the preload of the compression coil spring 66, and the bolt 162 is always in a state equivalent to being fixed to the first member 52. When the first member 52 and the second member 44 approach each other due to bending at the universal joint from a state in which the tapered surfaces 62 and 64 are engaged and aligned, the approach is caused by the compression coil. If the first member 52 and the second member 44 are allowed to separate due to the compression of the spring 66, the separation is allowed due to the compression of the compression coil spring 164.

The present invention can be implemented with various modifications and improvements based on the knowledge of those skilled in the art.

[Brief explanation of the drawing]

FIG. 1 is a front sectional view of a bolt/nut tightening device according to an embodiment of the present invention, and FIG. 2 is a front view of the same. FIG. 3 is a front view of a joint member which is one component of the above device, and FIG. 4 is a side view of the same. FIG. 5 is a sectional view taken along the line V--■ in FIG. 1. 6, 7, and 8 are front views showing the operating state of the bolt/nut tightening device. FIG. 9 is a front sectional view showing a part of a bolt/nut tightening device according to another embodiment of the present invention. 10: Driven member 12: Intermediate transmission shaft 14: Socket 16: Rotation drive device 24. 26: Joint
42: Device body 50: Housing 58 Two-spherical bearing 60 Guide 62.64: Tapered surface 66: Compression coil spring 68: Connection/alignment device 70 Guide 72.74: Tapered surface 77: Compression coil spring 81: Connection/axis alignment Device 160 Guide 164: Compression coil spring

Claims (1)

[Claims] A socket that is engaged with a bolt head or a nut;
A driven member that is engaged with a drive shaft of a rotary drive device and an intermediate transmission shaft that transmits rotation of the driven member to the socket, the socket and the intermediate transmission shaft, and the intermediate transmission shaft and the driven member are respectively connected. Connecting each set as a member
They are connected to each other by an alignment device, and each of the sets of connection/alignment devices (a) is capable of transmitting rotational torque between the connected members and, at least within a certain angular range, can rotate around approximately one point at any angle. (b) a first engagement member each having a first engagement surface and a second engagement surface that coaxially position the connected members by engaging with each other; (c) a biasing means for biasing the first and second engagement members in a direction in which the first and second engagement surfaces engage with each other; Bolt/nut tightening device.