JPS63200928A - Semi-automatic screw fastening device - Google Patents

Abstract

PURPOSE:To make it possible to engage a screw threadedly with a workpiece by gripping and securing the workpiece by use of a motor, gears and a sensor on the motor driven chuck side, and by screwing the screw into the workpiece to a predetermined depth by use of a motor, gears, a clutch and a sensor on the spindle side. CONSTITUTION:A joint J is inserted into a holder 21 under such a condition that a pipe is inserted into the joint J by 2 or 3 thread ridges, and a motor 11 is started to grip and fix the outer surface of the pipe P with the use of the pawls 14 of a motor driven chuck 14 through the intermediary of gears G1, G2, and the condition of the gripping is confirmed by use of a sensor 15. Then a motor 22 is started so as to associatingly drive gears G5, G6 through the intermediary of gears G3, G4, intermediate shafts 24, 26 and a clutch 25, and a spindle 20 is rotated in the fastening direction. Further, when the threaded engagement of the screw is inserted to a predetermined depth, the clutch 25 is automatically disengaged due to the resistance against the rotation while a sensor 27 confirms the stop of rotation of the gear G5, and then the motor 22 is stopped so as to complete the screw. Thus, it is possible to enhance the efficiency of the screw fastening and the production quality.

Description

[Detailed Description of the Invention] [Objective of the Invention] (Industrial Application Field) The present invention provides a method for attaching a screw to a male thread carved into the end of a pipe, for example, when performing piping work at a construction site. This invention relates to a semi-automatic screw tightening machine that is used to connect female threads carved into pipe joints such as elbows, cheeses, and various sockets and unions by screwing them together.

(Prior art) Generally, for this type of work, a simple vertical vise and hand tools such as a pipe wrench are used to adjust the pipes and pipe joints to the specified construction dimensions. He performs a wide variety of plumbing work while tightening screws.

(Problems to be solved by the invention) However, in the conventional construction method described above, almost all the processing is done by hand, so the work efficiency is very low and the construction is extremely time-consuming. Of course, when tightening a screw, it is easy to use too much or too little torque, so when the turning force is weak, it can cause water or gas leaks, and on the other hand, when the turning force is too strong, it can destroy important screw threads. There is a problem in that it is very difficult to always tighten the screws with the appropriate torque using manual operation because there is a risk of the screws being damaged.

This invention was developed in order to solve the above-mentioned difficulties, and its purpose is that once the machining setup is completed, the operator only needs to carry out the loading and unloading of the workpiece. It is an object of the present invention to provide a semi-automatic screw tightening machine that can always accurately and efficiently adjust torque, open and close a chuck, rotate a workpiece, etc.

[Structure of the invention]

(Means for Solving the Problems) The structure of the semi-automatic screw tightening machine according to the present invention for achieving the above object is such that one of the workpieces to be screwed is gripped and fixed from the outer periphery to the main operating part of the machine body. An electric chuck that holds the other workpiece and a main shaft with a holder that rotates while holding the other side of the workpiece are installed facing each other on the same central axis. A motor, a power transmission gear, and a sensor for detecting the completion of operation are installed on the main shaft side, and a clutch that interlocks with the motor, the power transmission gear, and its intermediate shaft only at a predetermined torque or less, and a sensor for detecting the completion of operation are installed on the main shaft side. It is characterized by being equipped with a sensor for use.

(Embodiment) Hereinafter, the present invention will be specifically explained with reference to drawings of embodiments. The drawings show an example of an implementation structure when the present invention is applied to a vertical screw tightening machine for piping.

In the drawings, reference numeral 1 is the frame of the aircraft, and a base plate 1a provided at the bottom of the frame 1 has a pair of handles 2, 2 on the left and right protruding upward, as well as a pair of handles 2, 2 on the four corners of the base plate 1a. Legs 3 for level adjustment are extendably protruded downward, and one of the workpieces to be screwed (pipe P in this example) is attached to the main operating part of the machine.
An electric chuck 1o that grips and fixes the workpiece from its outer circumferential surface and a main shaft 20 with a holder 21 that rotates while gripping the other workpiece (in the case of this example, the pipe joint J) are vertically opposed to each other. It is installed on the central axis.

Among these, various chucks can be used as the electric chuck 10 depending on the shape and dimensions of the workpiece, but in the case of this embodiment, a commercially available hammer chuck is used, and its prime mover is a frame An induction motor 11 attached to the upper left side of the chuck 1 is used.
0 is operated by a gear G□P Gz that rotates in conjunction with the output shaft 12 of the motor 11, and engages with the protrusion 13a without rotating the disc 12 having a spiral protrusion 13a on the upper surface. The claws 14 are moved back and forth toward the center to grasp and fix the workpiece P from the outer periphery. In addition,
Reference numeral 15 in the drawings denotes a photosensor provided on the side of the output shaft 12 of the motor 11. When the chuck 10 is in operation, a notch 16a provided in the rotary plate 16 at the top of the gear G□ is optically detected using a slit 15a. Sense and turn it on and off
Completion of the operation of the chuck 10 is confirmed when the signal disappears for one second or more.

On the other hand, on the upper part of the main shaft 20 which is rotatably supported in the center of the frame 1 facing the chuck 10, there are holders 21 of different sizes depending on the dimensions of the pipe joint to be clamped. A flange 20a that fits into the groove 21a on the lower surface of the holder
The power for rotating the main shaft 20 is supplied from the base plate l of the frame 1.
Power is supplied from the motor 22 installed on the main shaft 20 through the following power transmission path.

In the case of this embodiment, a gear motor is used as the motor 22, and the rotation of the motor 22 is transmitted to the lower intermediate shaft 24 via a gear G wedged on the output shaft 23 and a gear G meshing with the output shaft 23. , is transmitted to the input side of the powder clutch 25, and then transmitted from the output side to the upper intermediate shaft 2G only when the clutch 25 is connected, and further by the gear Gb meshing with the gear G of the upper intermediate shaft 26. The power is transmitted to the lower end of the main shaft 20, and the upper intermediate shaft 26
A photosensor 27 similar to that of the chuck 10 described above is provided on the side of the chuck 10, and when the main shaft 20 rotates, the intermediate gear G
, the notch 28a provided in the upper rotary plate 28 is connected to the slit 2.
7a, and when the ON/OFF signal is not output for one second or more, the role is to confirm that the rotation operation (screw tightening operation) of the workpiece J by the holder 21 on the spindle 20 side has been completed. fulfill

Note that FIG. 3 shows an example of the control panel 4 for operating the screw tightening machine M of the present invention, and the operation panel 5 of the control panel 4 includes a power switch, a motor start/stop switch, etc. A screw tightening torque adjustment dial 6 is provided to control the operation of the powder clutch 25 according to the type and dimensions of the workpieces P and J, and the control panel 4 and the screw tightening machine M are provided with a dial 6 for adjusting the screw tightening torque.
are connected by a cord 7 with an insertion plug, and a hand switch 8 for starting and stopping is attached to the top of the frame 1 of the screw tightening machine M, but the control panel 4 is not necessarily the same as in this embodiment. There is no need to use a separate type, and this may be incorporated into the screw tightening machine M itself.

In addition, the drawing shows an embodiment in which the present invention is applied to a vertical screw tightening machine for piping. The position facing the main shaft 20 that is held and rotated is 1 and 10.
20 are on the same axis, there is no problem even if they are arranged facing each other laterally or diagonally, and the workpiece P,
The machine may be configured so that processing can be performed with the fixed positions of J being reversed.

Since the screw tightening machine M of the present invention has the above-described structure, when the pipe fitting J is screwed onto one end of the pipe P during piping work, the operator has to tighten the pipe P. With the male threaded part screwed into the female threaded part of the pipe joint J by about 2 to 3 threads, pass the pipe joint J at the lower end through the center of the electric chuck 10 from above the machine and connect it to the upper end of the main shaft 20. After inserting it into the holder 21, when the push button of the hand switch 18 is pressed down to drive the machine, the upper condenser motor 11 is started and the winter melon 14 of the hammer chuck 10 is moved to the center through the gears G, , G. The claws 14 grip and fix the outer peripheral surface of the pipe P immovably. Said motor 1
During operation 1, the photo sensor 15 detects the movement of the claw 14 by the rotation of the gear G□, and when the ON/OFF signal is no longer output for about 1 second or more, it confirms that the gripping operation of the workpiece has been completed, and automatically restarts the operation. Then, the gear motor 22 at the bottom of the frame 1 is started to start screw tightening operation.

That is, when the gear motor 22 is driven, the rotational movement of the motor 22 is caused by the gear G3. It is transmitted to the lower intermediate shaft 24 through G4, and further transmitted to the upper intermediate shaft 2 through the powder clutch 25.
6, the main shaft 20 is rotated in the screw tightening direction by interlocking the gears G, , G. When the threads of the pipe joint J and the pipe P are screwed together to the desired depth by the above operation, the powder clutch 25 is automatically disconnected when the rotation resistance reaches a predetermined set value, and the gear G5 is turned off. When the photo sensor 27 confirms that the rotation has stopped by turning ON and OFF signals, the gear motor 22 is stopped, and the upper condenser motor 11 is rotated in the reverse direction to move the winter melon 14 of the electric chuck 10 back to its original position. Then, the series of screw tightening operations are completed, so after this, the pipe P and pipe joint J screwed together after processing are taken out upwards, the next workpiece is inserted, and the series of screws is tightened. Just repeat the action.

〔Effect of the invention〕

As described above, if the semi-automatic screw tightening machine of the present invention is used for various types of screw tightening work such as piping work at construction sites, the operator can only perform the feeding operation of the workpiece after setting up the machining process. By simply opening and closing the chuck, rotating the workpiece, adjusting the torque when tightening screws, etc., all operations are performed automatically and accurately at all times, simplifying the work and improving the quality and efficiency of construction. You can improve your performance.

[Brief explanation of the drawing]

Fig. 1 is a vertical cross-sectional view of the main parts showing an example of a specific implementation structure of a semi-automatic screw tightening machine according to the present invention, Fig. 2 is a cross-sectional view of the same, and Fig. 3 is a front view showing an example of a control panel. be.

Claims (1)

[Claims] An electric chuck that grips and fixes one of the workpieces to be screwed together from the outer periphery and a main shaft with a holder that rotates while gripping the other workpiece are placed on the same central axis in the main operating part of the machine. The electric chuck side is equipped with a motor that advances and retreats the jaws of the chuck toward the center, a power transmission gear, and a sensor for detecting the completion of operation. and a semi-automatic screw tightening machine, characterized in that a power transmission gear and its intermediate shaft are provided with a clutch that interlocks only when the torque is below a predetermined value, and a sensor for detecting completion of operation.