JPH081456A - Automatic bolt and nut loosening and fastening device - Google Patents

Abstract

PURPOSE:To loosen and fasten a large diameter bolt and nut which require large torque by providing a rotary means through the intermediary of a clutch for transmission and cut-off of drive torque in accordance with rotary reaction torque of a rotary means. CONSTITUTION:If reaction torque is less than prescribed torque, a socket rotating tool 4 is fixed. Further, if the reaction torque exceeds the prescribed torque, the socket rotating tool 4 itself can be rotated by a clutch 7 in a direction reverse to a direction in which is a socket is rotated, about the rotation axis 4a of the socket 3. With this arrangement, a reaction receiver 5 fixed to the lower outer peripheral side part of the socket rotating tool 4 abuts against a projected part of the wall surface 8 or the like of a workpiece in the vicinity of a bolt to be fastened. Accordingly, reaction torque exceeding prescribed torque for a robot 6 for handling the socket rotating tool 4 is cut off, and simultaneously the bolt 2 is loosened.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to automation of loosening and tightening work of bolts and nuts, and it is possible to efficiently and safely automate the work of loosening and tightening large-diameter bolts and nuts which require a large torque. The present invention relates to a bolt / nut attaching / detaching device for tightening.

[0002]

2. Description of the Related Art In industries such as the steel industry, which are so-called equipment industries, in order to maintain the function of production equipment and provide stable production, the production equipment is disassembled to repair the inside or replace consumable parts. Maintenance work such as performing and reassembling is regularly performed. Loosening and tightening work of bolts and nuts is one of the main works in such disassembly and assembly.Because large diameter bolts and nuts that require large torque are handled, loosen the bolts and nuts while striking a spanner with a hammer. The current situation is to force workers to perform dangerous and heavy muscle work such as tightening work. Also,
There is a large-diameter bolt fastening machine equipped with a reaction force receiver for hand tools, which is used in the bridge and construction industry in actual work and contributes to the improvement of dangerous and heavy muscle work, but dangerous and heavy muscle work is still complete. Is not solved yet.

On the other hand, a technique relating to automation of bolt / nut tightening work has been proposed and put to practical use in many fields including automobile manufacturing and tunnel construction. For example, the automatic tightening device disclosed in Japanese Utility Model Laid-Open No. 62-172527 is an automatic tightening device in which a socket having a hole for inserting a bolt head or a nut is connected to a rotary shaft extending from a tool body through a universal joint. By providing guide means for fixing the socket to the tool body so as to be rotatable and movable in the X and Y directions, and by providing a fixed position holding means for holding the guide means in a fixed position,
This enables automatic alignment of the axis of the tightening tool and the axis of the bolt hole regardless of the size, shape or type of the work.

[0004]

However, in the tightening device in which the guide means and the tool body are fixed, when the large-diameter bolt is tightened, the moving means itself for handling the guide means and the tightening device is tightened. It must have the rigidity to withstand the large torque of time,
It is necessary to increase the size of the entire device to ensure rigidity, and in many cases when designing the device assuming automation
There is a problem that it is contrary to the fact that weight reduction can be an important design condition.

Further, in the case of a manual tool, the transmission of a large torque to the operator is eliminated by providing a reaction force receiver. In this case, the bolt fastening machine is fitted to the bolt so that the reaction force receiver functions. Is easy, but if you assume automation,
In order for the reaction force receiver to function, the tool body should be positioned so as to cancel the reaction force by abutting the reaction force receiver on the protrusion or wall with the bolt and socket engaged, or by rotating the reaction force receiver to react. It is necessary to move to a position where the force receiving works. The device for automating the tightening work of the bolts and nuts is described in the above-mentioned Japanese Utility Model No. 62-17252.
Although a large number of proposals have been made including the publication No. 7, there have been few proposals so far for a device that is intended for automation of loosening work.

[0006]

SUMMARY OF THE INVENTION The present invention advantageously solves the problems of the prior art described above.
(1) A bolt / nut that includes a socket for loosening and tightening a bolt and a nut, has a drive source that can rotate the socket forward and backward, and has a rotating means that can be positioned relative to the bolt and the nut. In the loosening and tightening device, the rotating means is provided via a clutch that transmits and cuts the drive torque according to the rotational reaction torque generated by the rotating means, and the reaction force receiving means is provided below the outer peripheral side surface of the rotating means. (2) In the above item (1), the clutch includes a rolling element, a mounting flange having a groove for positioning the rolling element, and capable of mounting a socket rotary tool, and an elastic member. Body, a cover having a groove for positioning the rolling element and holding the rolling element, the mounting flange and the elastic body, the socket of the rotating means. Rotating shaft bolts and nuts automatic loosening clamping device being characterized in that the said rotating means rotates and fixed that can toggle between the torque limiter itself centered on,
(3) In the preceding paragraph (1), the clutch is a slip joint composed of an elastic body and a sliding plate, and a bolt and nut automatic loosening and tightening device is provided, (4) The preceding paragraph (1)
In the above, the gist of the present invention is a bolt / nut automatic loosening and tightening device, characterized in that the clutch comprises a means for detecting the rotational reaction torque, an electromagnetic clutch, and a control means for the electromagnetic clutch.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows an embodiment based on claim 1, which has a socket 3 for loosening and tightening the bolt 1, and a rotary shaft 4a having a tip shape to which the socket can be attached. The socket rotating tool 4 for generating the loosening and tightening torque of the socket, and the moving device such as the robot 6 for moving and positioning the socket 3 to the attachment / detachment position of the bolt 1 are set to the extent of the reaction torque due to the rotating torque of the socket rotating tool 4. Accordingly, a bolt provided with a reaction force receiver 5 mounted on a clutch 7 capable of interrupting the transmission of the reaction force torque to the moving device and receiving the reaction force torque on the outer peripheral lower side surface of the socket rotation tool 4. It is an automatic attachment / detachment device.

The present invention will be described by taking the bolt loosening work as an example. It is possible to limit the transmission of the reaction torque to the entire apparatus by switching the transmission torque between two steps or steplessly according to the reaction torque due to the rotation. By connecting the robot 6 and the socket rotation tool 4 having the reaction force receiver 5 that receives the reaction force torque via the simple clutch 7,
If the reaction torque is less than the specified torque, the socket rotating tool 4 is fixed. If the reaction torque exceeds the specified torque, the socket rotating tool 4 itself rotates the socket 3 by the clutch 7 around the rotating shaft 4a. The socket rotation tool 4 can be rotated in the direction opposite to the socket rotation.
The robot 6 for handling the socket rotation tool 4 receives the reaction torque due to the large torque as the reaction force receiver 5 fixed to the outer peripheral portion of the lower part of the workpiece abuts the projecting portion such as the work wall surface 8 near the target bolt. The reaction torque exceeding the specified torque can be cut off and the bolt 1 can be loosened at the same time.

As an example, the case of performing the automatic loosening work of the bolt will be described. Since the bolt 1 is in a state in which the upper work 2a and the lower work 2b having the work wall surface 8 near the bolt are already fastened, the robot 1 is first described. 6, the socket 3 and the socket rotation tool 4 provided with the reaction force receiver 5 are moved above the bolt 1 and positioned. Next, the socket rotation tool 4 is activated, and the robot 6 is lowered to a position where the tip of the socket 3 comes into contact with the upper work 2a.
Is engaged with one bolt. At the same time when the socket 3 engages with the bolt 1, the driving torque of the socket rotation tool 4 starts loosening the bolt 1. However, when the reaction torque generated at this time exceeds the specified torque, the clutch 7 operates to rotate the socket. The transmission of the reaction torque between the tool 4 and the robot 6 is interrupted, and at the same time, the socket rotation tool 4 itself is freely rotatable about the rotation shaft 4a. In addition,
At this time, the specified torque at which the clutch 7 is released from the fixed state and is rotatable is set to a value as small as possible within a range in which it is larger than the torque required when the socket 3 and one bolt are engaged. When the socket rotating tool 4 itself becomes rotatable by the operation of the clutch 7, the driving torque of the socket rotating tool 4 acts as a force for rotating the socket rotating tool 4 itself in the direction opposite to the rotation of the socket 3. Therefore, the socket rotation tool 4 starts to rotate about the socket 3 as a fulcrum, and accordingly, the reaction force receiver 5 fixed to the socket rotation tool 4 rotates until it abuts on the work wall surface 8 in the vicinity, and the reaction force receiver 5 rotates. The rotation of the socket rotation tool 4 itself, which comes into contact with the wall surface 8, stops, and the torque applied to the socket 3 increases again. At this time, the reaction torque is received by the reaction force 5 from the socket 3.
The reaction torque is not transmitted to the entire device because it is received between them. Then, when the drive torque of the socket rotation tool 4 reaches the loosening torque of the bolt 1, the bolt 1 starts to loosen, and then the bolt 1 can be easily loosened.

When the bolt is automatically tightened, the socket rotary tool 4 is positioned in the bolt hole 1a, and then the temporary tightening is performed. The temporary rotary tightening is performed by driving the socket rotary tool 4. Since the reaction torque generated is small, the clutch 7 does not operate, and the reaction torque increases at the same time as the temporary tightening is completed, and the bolt is finally tightened. At this time, the clutch 7 whose reaction torque exceeds the specified torque
Is activated to make the socket rotation tool 4 rotatable, and a reaction force receiver 5 fixed to the lower side surface of the socket rotation tool 4
Rotates together with the socket rotation tool 4 until it comes into contact with the nearby work wall surface 8. When the reaction force receiver 5 comes into contact with the work wall surface 8, the rotation of the socket rotation tool 4 itself stops, and the torque applied to the socket 3 increases again to perform the final tightening. The reaction torque generated at this time is received between the socket 3 and the reaction force receiver 5 as in the tightening, so that the reaction torque is not transmitted to the entire device. Then, when the drive torque of the socket rotating tool 4 reaches the tightening torque of the bolt 1, the socket rotating tool 4 stops and the tightening of the bolt 1 is completed.

The embodiment shown in FIG.
2 is a sectional view showing an embodiment based on FIG.
FIG. 7B is an enlarged view of a portion B in (a), in which the roller 10a is pressed by a spring 9 into and out of a roller groove 10b provided between the mounting flange 12a and the case 11a. This is a torque limiter that switches between rotation and stop in stages.

The embodiment shown in FIG. 3 is a sectional view showing an embodiment based on the above-mentioned claim 3, in which the clutch 7 is provided with a spring 9a so that a mounting flange 15b presses a sliding plate 13 in a case 14b. This is a sliding joint system in which the rotation / stop of the mounting flange 15b is continuously changed by the frictional force generated by the provision.

An embodiment shown in FIG. 4 is a sectional view showing an embodiment based on the above-mentioned claim 4, in which the clutch 7 detects a reaction torque by a torque sensor 18, and a solenoid 19, a brake shoe 20, An electromagnetic brake composed of the mounting flange 17c and the case 16c is used to switch between rotation and stop of the mounting flange 17c.

Although the bolt automatic loosening and tightening work has been described above, it goes without saying that the nut automatic loosening and tightening work can be performed by the same method.

[0015]

As described above, according to the present invention, it is possible to satisfy the above problems while saving labor and rationalizing the bolt and nut automatic loosening and tightening work.

[Brief description of drawings]

FIG. 1 (a) is a side view showing an example of the device of the present invention, (b).
Is a view on arrow AA in (a).

FIG. 2A is a sectional view showing an example of a clutch mechanism in the device of the present invention, and FIG. 2B is a detailed view of a B portion in FIG.

FIG. 3 is a sectional view showing another example of the clutch mechanism in the device of the present invention.

FIG. 4 is a sectional view showing still another example of the clutch mechanism in the device of the present invention.

[Explanation of symbols]

 1 Bolt 1a Bolt hole 2a Upper work 2b Lower work 3 Socket 3a Hexagonal hole 4 Socket Rotating tool 4a Rotating shaft 5 Reaction force receiving 6 Robot 7 Clutch 8 Work wall surface 9 Spring 10a Roller 10b Roller groove 11a, 14b, 16c Case 12a, 15b , 17 Mounting flange 13 Sliding plate 18 Torque sensor 19 Solenoid 20 Brake shoe

Claims (4)

[Claims] 1. A bolt having a socket for loosening and tightening a bolt and a nut, having a drive source capable of rotating the socket forward and backward, and having a rotating means capable of positioning relative to the bolt and the nut. In the nut loosening and tightening device, the rotating means is provided via a clutch that transmits and cuts the drive torque according to the rotational reaction torque generated by the rotating means, and the reaction force receiving means is provided below the outer peripheral side surface of the rotating means. An automatic loosening and tightening device for bolts and nuts. 2. The clutch has a rolling element, a groove for positioning the rolling element, a mounting flange to which a socket rotary tool can be attached, an elastic body, a groove for positioning the rolling element, and the rolling element. 7. A torque limiter comprising a mounting flange and a cover for holding an elastic body, the torque limiter being capable of switching between rotation and fixation of the rotation means itself around a socket rotation axis of the rotation means. The bolt / nut automatic loosening and tightening device described in 1. 3. The bolt / nut automatic loosening and tightening device according to claim 1, wherein the clutch is a slip joint formed of an elastic body and a slide plate. 4. The automatic bolt / nut loosening / tightening device according to claim 1, wherein the clutch comprises a means for detecting the rotational reaction torque, an electromagnetic clutch, and control means for the electromagnetic clutch.