JPH0786319B2 - Automatic bolt / nut fastening device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bolt / nut automatic fastening device, and more particularly to a bolt / nut automatic fastening device provided in a segment automatic assembly device in a shield construction method.

[0002]

2. Description of the Related Art Conventionally, when a tunnel is excavated by a shield excavator, a ring-shaped inner peripheral surface of a pit behind the shield excavator is provided with a plurality of curved reinforced concrete bodies every time a predetermined length is excavated. Will be covered by the segment. The segment automatic assembly apparatus for assembling the segments one by one on the inner peripheral surface of the mine and connecting the segments to the existing segments includes a bolt / nut automatic fastening apparatus for fastening a plurality of bolts for connecting the segments to each other. Is provided. Recently, along with the increase in size of the shield, there has been a demand for an increase in size of bolts, an increase in fastening torque, and a higher speed of automatic bolt fastening.

As a conventional bolt / nut automatic fastening device, for example, as described in Japanese Patent Laid-Open No. 3-224998, a support frame which is movable in two directions of an axial direction and a radial direction of a tunnel is opposed to each other. A pair of hydraulic cylinders for moving drive for slidably mounting a pair of arms at their base end portions so as to be relatively close to and away from each other in the circumferential direction of the tunnel, and for moving and driving the pair of arms, respectively. And one fixed-side socket is provided on one arm, and one drive-side socket rotatably driven by a hydraulic motor provided on the base end of the other arm via a gear train is provided on the other arm. Bolts and nuts automatic fastening devices are in practical use.

[0004]

In the conventional bolt / nut automatic fastening device, the pair of arms is provided with the pair of fixed-side sockets and the drive-side socket. There is a limit to the change. Therefore, it is conceivable to provide a plurality of pairs of fixed side sockets and drive side sockets on one pair of arms. In this case, it is necessary to provide a plurality of hydraulic motors that respectively drive a plurality of drive-side sockets with high torque and high speed, but arrange the large-sized hydraulic motors as described above at the base end of the relatively small width arm. It is difficult to do so, the equipment becomes large, and if multiple hydraulic motors are driven in parallel by the parallel hydraulic drive circuit, the amount of oil required for low torque / high speed drive at the initial stage of bolt / nut fastening will be extremely high, The capacity of the pump becomes very large, and when driven in parallel as described above, the rotation amounts of multiple drive-side sockets cannot be synchronized, and multiple bolts and nuts can be synchronously fastened at the time of low torque fastening at the initial stage of fastening. There are problems such as becoming difficult.

Moreover, in the conventional bolt / nut automatic fastening device, a pinch mechanism for gripping each bolt one by one is provided on the arm provided with the fixed side socket, and the arm is gripped with the pinch mechanism. There is a bolt feed mechanism that automatically moves the bolts one by one in the axial direction by moving them with a hydraulic cylinder to automatically feed them to a predetermined fastening position. Therefore, it is also required to improve the efficiency of the bolt feeding mechanism.

An object of the present invention is to enable a plurality of bolts and nuts to be simultaneously fastened in a bolt and nut automatic fastening device, and to simultaneously fasten a plurality of bolts and nuts at the time of low torque fastening. It is to prevent the hydraulic pump from increasing in size, to prevent the hydraulic pump from increasing in size, and to improve the efficiency of bolt feeding.

[0007]

According to another aspect of the present invention, there is provided a bolt and nut automatic fastening device, wherein a pair of arms facing each other are provided on a support frame movable in at least one direction or two directions orthogonal to each other. A pair of movement drive means for moving and driving the pair of arms respectively is provided so as to be slidable relative to each other in a direction orthogonal to each other, and one arm is provided with a fixed side socket and the other arm is provided. In a bolt / nut automatic fastening device provided with a driving side socket that is rotationally driven, a plurality of fixed side sockets are provided on the one arm so as to be in a predetermined arrangement state corresponding to a plurality of bolts to be fastened. A plurality of drive-side sockets arranged in a predetermined arrangement state corresponding to the plurality of bolts on the other arm, and a plurality of drive units respectively linked to the drive-side sockets. The transmission system is provided, the other arm, via a plurality of drive force transmission system, in which a plurality of driving-side socket, provided with a plurality of rotary driving means for rotationally driving each independently.

According to a second aspect of the present invention, there is provided a bolt / nut automatic fastening device according to the first aspect, wherein each of the rotary drive means is provided with a first drive motor which is interlocked with an input portion of a drive force transmission system corresponding to the rotary drive means. And a second drive motor that is interlockingly connected to the section via clutch means. According to a third aspect of the invention, in the bolt / nut automatic fastening device of the second aspect, the first drive motor is a first hydraulic motor, the second drive motor is a second hydraulic motor, a plurality of first hydraulic motors and a plurality of first hydraulic motors. The hydraulic drive circuit for driving the second hydraulic motor is configured to be switchable between a series circuit that synchronously drives the plurality of first hydraulic motors and a parallel circuit that drives the plurality of first and second hydraulic motors in parallel. It was done.

According to a fourth aspect of the invention, in the second aspect, the first drive motor comprises an electric motor and the second drive motor comprises a hydraulic motor. According to a fifth aspect of the present invention, in the bolt / nut automatic fastening apparatus according to the first aspect, each rotation driving means is composed of a hydraulic motor interlockingly connected to an input portion of a driving force transmission system corresponding thereto.
The hydraulic drive circuit for driving the plurality of hydraulic motors is configured to be switchable between a series circuit that drives the plurality of hydraulic motors in series and a parallel circuit that drives the plurality of hydraulic motors in parallel. According to a sixth aspect of the present invention, in the bolt / nut automatic fastening apparatus according to the third aspect, the one arm is provided with pinch means capable of gripping a plurality of bolts of at least a part of the plurality of bolts. A plurality of bolts are configured to be movable in the axial direction through a movement driving means for moving and driving the arm and a pinch means.

[0010]

In the bolt / nut automatic fastening device according to the first aspect of the present invention, a plurality of fixed side sockets provided on one arm and a plurality of drive side sockets provided on the other arm cooperate with each other. Multiple bolts and nuts can be automatically fastened. This makes it possible to significantly improve the work efficiency of bolt / nut fastening.

According to another aspect of the present invention, there is provided a bolt / nut automatic fastening device, wherein each rotation driving means is interlocked with an input portion of a driving force transmission system for transmitting a rotation driving force to a driving socket, and a first driving motor. Since the second drive motor is interlocked and connected to the input unit via the clutch means, the plurality of first drive motors can be engaged and driven at the time of low torque and high speed engagement at the initial stage of the engagement, and the high torque at the latter stage of the engagement can be achieved. At the time of low speed engagement, engagement can be performed by the plurality of first drive motors and the plurality of second drive motors with the plurality of clutch means connected. As a result, the size of each motor can be reduced, the layout of the motor can be improved, and the size of the device can be prevented from increasing.

According to another aspect of the present invention, there is provided a bolt / nut automatic fastening device as set forth in claim 2, wherein the first drive motor is a first hydraulic motor and the second drive motor is a second hydraulic motor. When torque / high-speed engagement is performed, the hydraulic drive circuit is switched to a series circuit, and a plurality of first
Drive the hydraulic motor in series. As a result, a plurality of bolts and nuts can be synchronously fastened, and as a result, low torque and high speed fastening can be completed simultaneously for a plurality of bolts and nuts at the initial stage of fastening. When high torque / low speed engagement is performed in the latter half of the engagement, the hydraulic drive circuit is switched to the parallel circuit to drive the plurality of first and second hydraulic motors in parallel. This makes it possible to fasten with high torque.
The nut can be securely fastened to a predetermined fastening state. By providing the hydraulic drive circuit as described above, it is possible to reduce the size of the hydraulic pump.

In the bolt and nut automatic fastening device of the fourth aspect, in the second aspect, the first drive motor is an electric motor, and the second drive motor is a hydraulic motor. Torque / high-speed engagement is performed with a relatively small electric motor, and a high-torque hydraulic motor can be used for high-torque / low-speed engagement in the latter half of the engagement, and hydraulic pressure must be supplied to the first drive motor. Therefore, a relatively small hydraulic pump may be provided.

According to a fifth aspect of the present invention, in the bolt / nut automatic fastening device according to the first aspect, each rotary drive means is composed of a hydraulic motor, and when the low torque / high speed fastening is performed at the initial stage of fastening, the hydraulic drive circuit is provided. By switching to a series circuit, a plurality of hydraulic motors are driven in series. As a result, a plurality of bolts and nuts can be synchronously fastened, and as a result, low torque and high speed fastening can be completed simultaneously for a plurality of bolts and nuts at the initial stage of fastening. When high torque / low speed engagement is performed in the latter half of the engagement, the hydraulic drive circuit is switched to a parallel circuit to drive a plurality of hydraulic motors in parallel. As a result, it is possible to fasten the bolts and nuts with a high torque and securely fasten the bolts and nuts to a predetermined fastening state.
By providing the hydraulic drive circuit as described above, it is possible to reduce the size of the hydraulic pump.

According to a sixth aspect of the present invention, in the bolt / nut automatic fastening apparatus according to the third aspect, the one arm is provided with pinch means capable of gripping at least a part of a plurality of bolts, and the one arm is moved. Since a plurality of bolts are configured to be movable in the axial direction through a moving drive means for driving and a pinch means, it is possible to efficiently feed a plurality of bolts to a predetermined fastening position prior to automatic fastening of bolts and nuts. Can be increased and the cycle time of bolt and nut fastening can be shortened.

[0016]

Embodiments of the present invention will be described below with reference to the drawings. This embodiment is an example of a case where the present invention is applied to a bolt / nut automatic fastening device of a segment automatic assembly device provided as an accessory of a shield excavator for excavating a tunnel. It is called an "automatic fastening device." Here, when excavating a tunnel with a shield excavator, the inner peripheral surface of the tunnel excavation is lined with a segment made of reinforced concrete for each ring-shaped portion of a predetermined length in the axial direction of the tunnel.

As shown in FIG. 1, the segment 1 is
It has a predetermined length in the axial direction of the tunnel and a curved shape obtained by dividing the circumference in the circumferential direction, and when lining the inner peripheral surface of the mine, it has a ring shape of a predetermined length in the axial direction. Due to the lining for each part, the new segment 1A is
One axial end face and one circumferential end face are arranged in abutting contact with the existing adjacent segment 1B, and are connected to the adjacent segment 1B at a plurality of locations via bolts and nuts. With the automatic fastening device, three sets of bolts and nuts will be connected at each connection point.

In this automatic fastening device 10, a radial slide frame 12 is provided on a main body frame 11 of the automatic segment assembling device so as to be movable in the radial direction of the tunnel.
3 and is radially driven via the hydraulic motor 15 and the screw shaft 14. An axial slide frame 16 is provided at a guide portion at the tip of the radial slide frame 12 so as to be movable in the axial direction of the tunnel through a guide member 17, and the axial slide frame 16 serves as a hydraulic motor. It is axially moved and driven via a screw shaft.

A flexible hanger 18 is provided at the tip of the axial slide frame 16, and a support frame 20 extending for a predetermined length in the circumferential direction of the tunnel is vertically supported on the flexible hanger 18, and the flexible hanger is provided. 18 is configured to be switchable between an unlocked state in which the support frame 20 is rotatably supported around the support shaft 19 and a locked state in which the support frame 20 is fixedly supported by a mechanism provided therein. There is.

A first guide member 21 extending straight in the circumferential direction is provided at the lower end of the left half of FIG. 1 among the lower ends of the support frame 20, and the lower end of the right half is provided at the lower end. A second guide member 22 is provided which is higher than the first guide member 21 by a predetermined height and extends straight in the circumferential direction. A feed arm 23 is attached to the first guide member 21 so as to be slidable in the circumferential direction (left and right direction in FIG. 1) at its base end portion, and can be moved and driven in the left and right direction by a hydraulic cylinder 24 corresponding to a movement driving means. The fastening arm 25 is slidably attached to the second guide member 22 in the circumferential direction at the base end thereof, and can be moved and driven in the left and right directions by a hydraulic cylinder 26 corresponding to a movement drive means. It is configured.

The structure of the connecting portion for connecting the segments 1 to each other with bolts will be described. A recess 2 is formed in the vicinity of the end surface 1a of the segment 1 (circumferential end surface in FIG. 1). 2 and the end face 1a between the connecting wall portion 3
Is formed, and the steel plate 4
Is provided in an embedded state, and the connecting wall portion 3 is preliminarily formed with two bolt insertion holes 5 in the upper stage and the lower stage as shown in the figure.

In the socket holder 30 below the feed arm 23, as shown in FIG. 2, three fixed side sockets 31 (two upper stages and one lower stage) are arranged so as to correspond to the bolt insertion holes 5. The fixed sockets 31 are provided with the nuts 8 to which the washers are previously fixed via the rigid resin fasteners. As shown in FIG. 3, three drive side sockets 32 (two upper stages and one lower stage) are provided in the lower portion of the fastening arm 25 in an arrangement corresponding to the bolt insertion holes 5. The side sockets 32 are configured so that the nuts 8 to which washers are previously fixed can be mounted via the rigid resin fasteners, respectively.

Next, a fastening drive device for rotationally driving the three drive side sockets 32 will be described. 3 to 4
As shown in FIG. 3, at the base end (upper end) of the fastening arm 25, three first hydraulic motors 33 (corresponding to the first drive motors) and three second hydraulic motors 34 (second drive motors) are provided. Equivalent) and are provided. One of the center of the three first hydraulic motors 33 is on the right side of the fastening arm 25, and two of the three first hydraulic motors 33 on both sides are on the left side of the fastening arm 25. The output shaft 36 is provided with the output shaft protruding into the housing 35 of the fastening arm 25, and the output shaft 36 of the central first hydraulic motor 33 is composed of a plurality of gears 37 to 42 arranged in the right part of the housing 35. A gear train 44 (corresponding to a driving force transmission system) is interlocked with a gear 43 that is integral with the lowermost drive-side socket 32.

The output shafts 36 of the two first hydraulic motors 33 on the front and rear ends are a gear train 50 (corresponding to a driving force transmission system) composed of a plurality of gears 45 to 49 arranged in the left part of the housing 35. Via the upper two drive side sockets 3
The gears integrated with 2 are linked together. One of the center of the three second hydraulic motors 34 is on the left side of the fastening arm 25, and two of the two sides of the three second hydraulic motors 34 are on the right side of the fastening arm 25. , The output shaft 51 of the central second hydraulic motor 34 is provided in a state where the output shaft is projected into the housing 35 of the fastening arm 25 and concentrically with respect to the three first hydraulic motors 33.
Is the output shaft 36 of the central first hydraulic motor 33 via the one-way clutch 52 capable of transmitting driving force in the fastening direction.
Is connected to the gear 37 (corresponding to the input portion of the gear train 44). The output shafts 51 of the two second hydraulic motors 34 on the front and rear ends are connected to the gears of the output shafts 36 of the two first hydraulic motors 33 on the front and rear ends via the one-way clutch 52 capable of transmitting the driving force in the fastening direction. 45 (corresponding to the input section of the gear train 50). Further, in order to detect the number of rotations of the three drive side sockets 32, the gear train 44
Rotary encoder 53 for detecting the number of rotations of the two-stage gears 38 and 39 of the two gear trains 50 and the two-stage gears 46 and 47 of the two gear trains 50.
But each is provided. However, it is also possible to employ an electromagnetic clutch instead of the one-way clutch 52.

Next, the three first hydraulic motors 33 and 3
A hydraulic drive circuit that drives the two second hydraulic motors 34 will be described. As shown in FIG. 5, a hydraulic drive circuit 60 is configured, and the three first hydraulic motors 33 include a gear train 44,
The gears 37 and 45 corresponding to the input portions of the gear trains 50 and 50 are connected to the gears 37 and 45 corresponding to the input portions of the gear trains 44 and 50, respectively. Are connected through.

The hydraulic drive circuit 60 is provided with eight electromagnetic direction switching valves 61 to 68, which are connected via oil passages as shown in the drawing, and these switching valves 61 to 68 are shown in the drawing. It is controlled by an external control unit. The state of the switching valves 61 to 68 shown in the figure is the first position, and the state switched from the state shown is the second position.

At the early stage of fastening the bolts and nuts, when the low torque and high speed fastening is performed, the switching valve 6
4, 66, 68 in the first position and the switching valve 61,
When 62, 63, 65, 67 are switched to the second position, it is 3
The first hydraulic motors 33 are connected in series, and the hydraulic pump 6
The hydraulic pressure supplied from 9 is supplied in series to the three first hydraulic motors 33, the three first hydraulic motors 33 are driven in series, and the hydraulic pressure is not supplied to the three second hydraulic motors 34.

Next, in the latter half of the engagement, when high torque / low speed engagement is performed, the switching valves 63, 65, 67 are held in the first position, and the switching valves 61, 62, 64, 66, 68 are switched to the second position. The three first hydraulic motors 33 and the three second hydraulic motors 34 are connected in parallel to the hydraulic pump 69, and the hydraulic pressure from the hydraulic pump 69 is supplied to the three first hydraulic motors 33 in parallel. Thus, the three first hydraulic motors 33 are driven, and at the same time, the hydraulic pressure from the hydraulic pump 69 is supplied in parallel to the three second hydraulic motors 34 via the switching valve 68, and the three second hydraulic motors 34 are supplied.
Will be driven in parallel. The control oil passage 70 is for tilting angle control of the hydraulic motors 33, 34, that is, speed control.

As described above, the hydraulic drive circuit 60 includes a series circuit for driving the three first hydraulic motors 33 in series and a parallel circuit for driving the three first hydraulic motors 33 and the three second hydraulic motors 34 in parallel. It is configured to be switchable to.

Next, the bolt pinch mechanism 80 provided on the feed arm 23 for feeding the bolt 7 previously arranged in the bolt insertion hole 5 to the recess 2 to a predetermined fastening position will be described. As shown in FIG. 6, a left-side portion of the lower portion of the feed arm 23 is provided with a pivot shaft 81 oriented in the left-right direction, and the pivot shaft 81 is provided with a pair of first levers 82 in the front-rear direction.
A pair of second levers 83 is rotatably pivotally attached, and an upper end of the first lever 82 on the front side and an upper end of the second lever 83 are connected by a hydraulic cylinder 84. The upper end and the upper end of the second lever 83 are connected by a hydraulic cylinder 84.

The first lever 82 and the second lever 83 on both the front and rear sides are configured to be rotatable between a position shown by a solid line and a position shown by a chain line to retract the rod of the hydraulic cylinder 84. And the first and second levers 82 on the front and rear sides,
The solid line 83 indicates the state shown in the figure, and the hydraulic cylinder 84
When the rod is advanced, the first and second levers 82 and 83 on the front and rear sides are in the state shown by the chain line. Therefore, when grasping one bolt 7 at the bottom (see FIG. 7),
By switching the second levers 82 and 83 from the state shown by the chain line in FIG. 6 to the state shown by the solid line in FIG. 7,
The bolt 7 can be grasped by the pair of first levers 82, and when the upper two bolts 7 are grasped at the same time,
By setting the second levers 82 and 83 in the state shown by the solid line in FIG. 6 and then switching them to the state shown by the chain line,
The bolt 7 of the book can be grasped at the same time. As described above, by moving the feed arm 23 to the right by the hydraulic cylinder 24 in a state where one or two bolts 7 are gripped, the bolt 7 can be fed to the right (bolt axial direction). I can.

Next, the operation of the automatic fastening device described above will be described. First, in the state where the newly installed segment 1A is arranged, as shown in FIG. 8, the three bolts 7 are arranged as shown in the drawing, and the three fixed side sockets 31 of the feed arm 23 and the fastening arm 25 are arranged. The three drive-side sockets 32 are preloaded with nuts 8 to which washers are attached from a nut supply device (not shown).

First, the feed arm 23 is positioned on the left side of the recess 2 and lowered, and the bolt pinch mechanism 80 grips the two upper bolts 7 as described above.
The feed arm 23 is fed to the right by the hydraulic cylinder 24 until the socket holder 30 of the feed arm 23 comes into contact with the connecting wall portion 3, and the bolt feed is repeated a plurality of times in the same manner. Is set to a predetermined fastening position where it abuts against. Next, the lower one bolt 7
Is set to a predetermined fastening position where the right end of the bolt 7 comes into contact with the drive side socket 32 by bolt feeding a plurality of times as described above.

Next, after lowering the support frame 20 to a predetermined height position where the three fixed side sockets 31 and the three drive side sockets 32 face the three bolts 7,
The feed arm 23 is moved to the right by the hydraulic cylinder 24, the three fixed side sockets 31 are brought into contact with the left ends of the three bolts 7, respectively, and the fastening arm 25 is moved to the left by the hydraulic cylinder 26. 3 drive side sockets 3
When 2 is brought into contact with the right ends of the three bolts 7, respectively, the preparatory work for fastening the bolts and nuts is completed.

Next, while the feed arm 23 is biased to the right by the hydraulic cylinder 24 and the fastening arm 25 is biased to the left by the hydraulic cylinder 26, low torque and high speed fastening is performed. In this case, as described above, when the three first hydraulic motors 33 are simultaneously driven in series, the drive-side sockets 32 are fastened to the threaded portions at the right ends of the corresponding bolts 7 for the first time, and then the fixed-side sockets 32. 31 are fastened to the threaded portions at the left end of the corresponding bolts 7 at high speed.

Next, similarly to the above, high torque and low speed fastening is performed while urging the feed arm 23 to the right and the fastening arm 25 to the left. In this case, when the three first hydraulic motors 33 and the three second hydraulic motors 34 are simultaneously driven in parallel as described above, the three sets of bolts 7 and nuts 8 are strongly fastened. After that, the feed arm 23
By moving the fastening arm 25 to the left and the fastening arm 25 to the right to release the fixed side socket 31 and the driving side socket 32 from the nut 8 and move the support frame 20 upward. finish.

As described above, with respect to the fastening drive device of the automatic fastening device, the central gear train 44 is connected to the fastening arm 25.
Since the front and rear gear trains 50 are disposed in the right part of the housing 35 of the fastening arm 25, the front and rear gear trains 50 are disposed in the left part of the housing 35 of the fastening arm 25.
It was possible to accommodate 4, 50 in a volumetrically efficient manner, and the fastening arm 25 could be constructed in a comparatively small size. Further, since the three drive-side sockets 32 can be simultaneously driven, the work efficiency of bolt fastening can be dramatically improved.

The drive motor for driving each drive-side socket 32 is composed of the first hydraulic motor 33 and the second hydraulic motor 34, and these hydraulic motors 33, 34 are arranged concentrically and oppositely. Fastening arm 25 without increasing the size
The front and rear width (width in the axial direction) of the fastening arm 2 can be reduced.
5 was able to be miniaturized. Further, the second hydraulic motor 34 is connected to the input parts of the gear trains 44, 50 via the clutch 52, and the three first hydraulic motors 33 are driven in series at the time of low torque / high speed engagement in the initial stage of engagement, and the engagement is performed. Since the hydraulic drive circuit 60 that can drive the three first hydraulic motors 33 and the three second hydraulic motors 34 in parallel is provided during the high torque / low speed engagement in the latter period, the three drive side sockets 32 are provided in the initial stage of the engagement. Since it can be driven synchronously, low torque and high speed fastening can be completed at the same time, and immediately after that, it is possible to shift to high torque and low speed fastening in the latter stage of fastening, resulting in an improvement in fastening efficiency.

Since the three first hydraulic motors 33 are driven in series at the time of high-speed engagement at the initial stage of engagement in which the maximum amount of oil is consumed, it can be driven by a relatively small hydraulic pump 69, which reduces the running cost of engagement drive. It can be reduced. Furthermore,
Since the feed arm 23 is provided with the bolt pinch mechanism 80 so that the two bolts 7 can be fed at the same time, the efficiency of bolt feeding can be increased and the bolt fastening cycle time can be shortened.

Next, a modification in which a part of the above embodiment is modified will be described. 1) An electric motor is provided instead of each first hydraulic motor 33 of the fastening drive device. In this case, the low torque / high speed engagement in the initial stage of engagement can be executed by the relatively small electric motor, and the high torque / low speed engagement in the latter stage of the engagement can be executed mainly by the second hydraulic motor 34 of high torque / low speed. Therefore, the hydraulic pump 69 can be further downsized. 2) The second hydraulic motor 34 and the clutch 52 of the engagement drive device are omitted, and the engagement drive is performed only by the three first hydraulic motors 33, and the hydraulic drive circuit 60 is substantially the same as the above (however, The circuit for the second hydraulic motor 34 is omitted), and a circuit for connecting the three first hydraulic motors 33 in series and a circuit for connecting the three first hydraulic motors 33 in parallel can be configured to be switched. The three first hydraulic motors 33 are serially driven at the time of engagement, and the three first hydraulic motors 33 are serially driven at the time of high torque / low speed engagement in the latter half of the engagement.

3) An electric motor is provided instead of each first hydraulic motor 33 of the fastening drive device, and a high torque type electric motor is provided instead of each second hydraulic motor 34. 4) Instead of the gear trains 44 and 50 of the fastening drive device, a drive force transmission system using a sprocket and a chain is provided. The above-described embodiment is merely an example, and the structure for supporting the support frame 20 on the frame 11, the support frame 2
Regarding the structure of 0, the shapes of the feed arm 23 and the fastening arm 25, and the like, it goes without saying that various modifications can be appropriately made without departing from the present invention.

[Brief description of drawings]

FIG. 1 is a front view of a bolt / nut automatic fastening device according to an embodiment.

FIG. 2 is a side view of the feed arm of FIG. 1 (corresponding to the view of arrow 2 in FIG. 1).

3 is a side view of the fastening arm in FIG. 1 (a view corresponding to the arrow 3 in FIG. 1).

FIG. 4 is a sectional view taken along line 4-4 of FIG.

FIG. 5 is a configuration diagram of a hydraulic drive circuit.

FIG. 6 is a side view of a bolt pinch mechanism.

FIG. 7 is a side view of the bolt pinch mechanism.

FIG. 8 is a view corresponding to FIG. 1 when a bolt is fed.

[Explanation of symbols]

 20 Support Frame 23 Feeding Arm 25 Fastening Arm 31 Fixed Side Socket 32 Drive Side Socket 33 First Hydraulic Motor 34 Second Hydraulic Motor 44,50 Gear Train (Driving Force Transmission System) 52 One Way Clutch 60 Hydraulic Drive Circuit 61-68 Electromagnetic Direction Switching valve 69 Hydraulic pump

Claims (6)

[Claims] 1. A pair of opposing arms is slidably attached to a support frame movable in at least one direction or two directions orthogonal to each other so as to be able to relatively approach and separate in a direction orthogonal to the moving direction, A bolt / nut automatic fastening, in which a pair of movement driving means for moving and driving the pair of arms are provided, and one arm is provided with a fixed side socket and the other arm is provided with a rotationally driven drive side socket. In the device, a plurality of fixed-side sockets are provided on the one arm so as to be in a predetermined arrangement state corresponding to a plurality of bolts to be fastened, and a predetermined arrangement corresponding to the plurality of bolts is provided on the other arm. A plurality of drive side sockets arranged in a state and a plurality of drive force transmission systems linked to the drive side sockets respectively, and the other arm is provided with the plurality of drive force transmission systems. An automatic bolt / nut fastening device, characterized in that a plurality of rotation drive means for independently rotating and driving a plurality of drive-side sockets are provided via a drive system. 2. Each of the rotary drive means has a first drive motor interlockingly connected to an input portion of a corresponding drive force transmission system, and a second drive motor interlockingly connected to the input portion via clutch means. The bolt / nut automatic fastening device according to claim 1, characterized in that: 3. The hydraulic drive for driving the plurality of first hydraulic motors and the plurality of second hydraulic motors, wherein the first drive motor comprises a first hydraulic motor, the second drive motor comprises a second hydraulic motor. 3. The circuit is configured to be switchable between a series circuit that drives a plurality of first hydraulic motors in series synchronously and a parallel circuit that drives a plurality of first and second hydraulic motors in parallel. The described bolt / nut automatic fastening device. 4. The bolt / nut automatic fastening device according to claim 2, wherein the first drive motor is an electric motor, and the second drive motor is a hydraulic motor. 5. Each of the rotary drive means comprises a hydraulic motor linked to an input portion of a corresponding drive force transmission system, and a hydraulic drive circuit for driving the plurality of hydraulic motors comprises a plurality of hydraulic motors. The bolt / nut automatic fastening device according to claim 1, wherein the bolt / nut automatic fastening device is configured so as to be switchable between a series circuit for driving a plurality of hydraulic motors in series and a parallel circuit for driving a plurality of hydraulic motors in parallel. 6. The one arm is provided with pinch means capable of gripping at least some of the plurality of bolts, and the movement driving means and the pinch means for moving and driving the one arm. The bolt / nut automatic fastening device according to claim 3, wherein a plurality of bolts are configured to be movable in the axial direction via the.