JP3038466B2 - Socket automatic screw fitting method and screw fitting 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 method and an apparatus for automatically screwing a socket with a threaded socket fitted to an end of a steel pipe.

[0002]

2. Description of the Related Art At present, when shipping a steel pipe having threaded outer peripheral walls at both ends of a pipe, generally, a socket is screwed into one end of the pipe and a temporary socket (protection cap) is fitted into the other end. Have been done.

Conventionally, as means for screwing a socket into an end of a steel pipe, a method of chucking the outer peripheral surface of the socket with a grip-type chuck, pushing the socket toward the steel pipe while rotating the steel pipe, and fitting and screwing the socket. Is generally adopted.

[0004] However, the above-mentioned conventional method has the following problems. That is, the shape of the outer peripheral surface of the socket may not be constant, and particularly in the case of a malleable cast iron socket, the shape of the outer peripheral surface is not uniform. Therefore,
With the method of chucking the outer peripheral surface of the socket, if the center of the claw of the chuck is aligned with the centerline of the steel pipe, but the centerline of the threaded surface of the socket can not exactly match the centerline of the pipe When occurs, centering is crazy even a little, particularly for tapered threads, without exactly fit the threads, screw engagement, when you put this in unreasonable,
You will break the threads. Therefore, in the conventional method, defective products were generated due to screw engagement, and the occurrence rate of the defective products increased in proportion to the operation speed of the apparatus.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has a threaded socket stably and efficiently fitted and screwed into a threaded portion at the end of a steel pipe without meshing screws. It is an object of the present invention to provide a socket automatic screw-fitting method and a screw-fitting device.

[0006]

Means for Solving the Problems In order to achieve the above object, of the present invention , the invention according to claim 1 is characterized in that a steel pipe having a tapered external thread formed on an outer peripheral wall surface of an end of a pipe is provided with a cylindrical body. Insert a tapered female screw into the inner wall surface
In a socket automatic screwing method for fitting and screwing a symmetrically formed socket, there is provided a support means for horizontally supporting a steel pipe and a chuck mechanism provided opposite to an end face of the steel pipe supported by the support means. And the chuck mechanism is
The outer wall surface of each of these nails has an inner peripheral surface of the cylindrical body.
Formed on an arc surface corresponding to the wall surface and a tapered tapered surface
By pressing each of the claws of the chuck mechanism against the inner peripheral wall surface of the socket to fix and support the socket, centering of the socket with respect to the steel pipe is performed, and the supporting means or /
And, the socket is fitted to the screw portion of the steel pipe by rotating and approaching the steel pipe and the socket relatively by the chuck mechanism.

[0007] In the present invention, the invention according to claim 2 is a tube.
Steel pipe with tapered external thread formed on outer peripheral surface of body end
And a tapered female screw that engages with the above screw on the inner peripheral wall of the cylindrical body.
A socket for fitting and screwing a socket with a symmetrically formed socket
In the automatic screw-fitting device, a supporting means for horizontally supporting a steel pipe, a chuck mechanism provided opposite to an end face of the steel pipe supported by the supporting means, and supported by the supporting means
Driving means for rotating the steel pipe or / and the chuck mechanism,
And a drive that makes the steel pipe and the chuck mechanism relatively close to each other.
And a motion means, the chuck mechanism has a plurality of claws, the outer peripheral wall surface of each of these claws pair on the inner peripheral wall surface of the tubular body
Formed on the corresponding arc surface and tapered taper surface.
Each of the claws is configured to be pressed against the inner peripheral wall surface of the socket to fix and support the socket.

[0008]

[Function] The inner peripheral wall surface of the threaded socket is subjected to thread cutting, so that the precision is accurately obtained. According to the present invention, the inner peripheral wall surface where accuracy is obtained by this threading is used as a reference surface, and the nail of the chuck mechanism is pressed against the inner peripheral wall surface to center the socket with respect to the steel pipe. The center line does not deviate exactly from the center line of the steel pipe, so that the socket is perfectly supported and the socket is fixedly supported. When the steel pipe and the socket are relatively rotated in this state and approached to each other, the socket is fitted to the end of the pipe while maintaining the centering state by the claw, so that the screw is not engaged with the steel pipe, and It is screwed in orderly.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an explanatory view showing the principle configuration of a socket automatic screwing device according to the present invention. An external thread 2 is formed, and the illustrated thread 2 is formed by a tapered tapered thread. The socket S connects the steel pipes P to each other, and is made of a material such as malleable cast iron, steel, or plastic, and has a female screw 4 screwed to the screw 2 on the inner peripheral wall surface of the cylindrical body 3 having an appropriate diameter and length. To form
The screw 4 of the illustrated socket S is configured such that a taper screw corresponding to the screw 2 is bilaterally symmetric.

The above apparatus has a support means 11 for horizontally supporting a steel pipe P, and a chuck mechanism 12 provided opposite to an end face of the pipe P supported by the support means 11. Is pressed against the inner peripheral wall surface (worked surface of the screw 4) of the socket S to fix and support the socket S, and the tube P and the socket S are relatively rotated and approached, and the socket S is inserted into the male screw 2 of the tube P. In this figure, the pipe P is rotated and the socket S is advanced to approach the pipe P in this figure, and the chuck mechanism 13 advances the chuck mechanism 12 in the pipe P direction. -Shows the driving means for retreating.

FIG. 2 is a side view showing an embodiment of a socket automatic screwing apparatus constructed by applying the principle of the present invention, and FIG.
FIG. 4 is a longitudinal sectional front view and a side view showing a state in which the socket is fixedly supported by the chuck mechanism of the embodiment device. In these figures, a supporting means 11 for horizontally supporting a steel pipe P of the apparatus of this embodiment comprises a pair of rollers 31, 31 having two rollers rotatably mounted with their outer peripheral surfaces facing each other at an appropriate distance. Arranged on the same axis with an interval, a steel pipe P is placed in the upper valley between the rollers of each roller pair 31 so as to be supported horizontally, and an arbitrary roller pair 31 is formed. By rotating in a predetermined direction, the pipe P
Is configured to rotate.

The steel pipe P is configured to be supplied to the support means 11 at a predetermined timing by a steel pipe supply section of an arbitrary configuration (not shown) and to be sent out of the support means 11 by a steel pipe delivery section at a predetermined time. In this case, the support means 1
It is also possible to arrange a plurality of tubes 1 in parallel so that a plurality of tubes P can be simultaneously supplied and delivered.

Chuck mechanism 1 for fixing and supporting socket S
Reference numeral 2 denotes a plurality of (three in the figure) claws 21, which are formed in an expanding chuck type for expanding the claws 21 and fixing an object to be fixed, that is, a socket S, and expanding the claws 21 to form a socket. The socket S is configured to be pressed against the inner peripheral wall surface (worked surface of the screw 4) to fix and support the socket S. The chuck mechanism 12 is arranged so that the center point 22 of the claw 21 (see FIG. 3) coincides with the center line of the pipe P supported on the roller pair 31 and guided by a guide 23 so as to be reciprocally movable in the horizontal direction. And
The drive means 13 such as a pressure cylinder 24 is configured to move forward and backward at a predetermined timing. Above
The outer wall surface 21A of each claw 21 of the jack mechanism 12 is
The circular arc surface corresponding to the inner peripheral wall surface of the cylindrical body 3 of the
It is formed on a tapered surface.

In FIG. 2, reference numeral 14 denotes an elevating means for pushing up the socket S. The elevating means 14 comprises a mounting table 41 on which the socket S is mounted, and an elevating drive unit 42 for moving the table 41 up and down.
The socket S supplied from a socket supply unit (not shown) is placed and pushed up to a predetermined position in front of the claw 21 of the chuck mechanism 12 at a predetermined timing.

The apparatus of the embodiment shown in FIG. 2 is structured as described above.
Then, the chuck mechanism 12 is advanced by the driving means 13 to insert the claw 21 into the socket S, and the claw 21 is expanded and pressed against the inner peripheral wall surface of the socket S to center and fix the socket S. Next, the chuck mechanism 12 is further advanced, and the socket S is fitted to the end of the rotating steel pipe P, so that the screws 2 and 4 are fitted and the socket S is screwed into the pipe P.

Next, experimental data for comparison between the conventional method of chucking the outer peripheral surface of the socket (conventional method) and the method of the present invention will be described. As a test object, a malleable cast iron socket was adopted, and as a result of an experiment for each of sockets of sizes 15A, 20A, and 25A, the conventional method was 800 to 1000 P / Hr
In the case of (quantity / hour), about 3% to 6% of defective products (such as screw-engaged products) occurred. Also, set the speed to 1000
When the ratio was increased to P / Hr or more, the rate of occurrence of defective products sharply increased, so that it became impossible to carry out. On the other hand, in the method of the present invention, each of the above-mentioned sizes achieved a speed of up to 1440 P / Hr, during which time no defective products were generated. Further, it was found that the method of the present invention can increase the production speed to about 1800 P / Hr by shortening the handling time.

In the embodiment shown in FIG. 2, the steel pipe P is rotated at a fixed position, and the socket S is moved forward and backward. However, the socket (chuck mechanism) is used.
Can be arbitrarily changed, for example, by rotating the tube or rotating both to move the tube P forward and backward.

[0018]

According to the present invention, the socket can be accurately centered and fixedly supported on the steel pipe, and the socket can be stably and efficiently screwed to the end of the steel pipe without meshing with screws. .

[Brief description of the drawings]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an explanatory view showing the principle configuration of a socket automatic screw fitting device according to the present invention. FIG. 1A shows a front work step, and FIG.

FIG. 2 is a side view showing one embodiment of an automatic socket fitting device configured by applying the principle of the present invention.

FIG. 3 is a longitudinal sectional front view A and a side view B showing a state in which a socket is fixedly supported by a chuck mechanism of the embodiment device.

[Explanation of symbols]

 P Steel pipe S Socket 2 Male screw 4 Female screw 11 Supporting means 12 Chuck mechanism 21 Claw

──────────────────────────────────────────────────続 き Continuation of the front page (56) References Japanese Utility Model Showa 47-34281 (JP, U) Japanese Utility Model Showa 57-181561 (JP, U) (58) Fields surveyed (Int. Cl. ⁷ , DB name) B23P 19/06

Claims (2)

(57) [Claims] 1. A tapered male taper on the outer peripheral wall of an end of a tubular body.
In a socket automatic screw-fitting method of fitting and screwing a socket in which a tapered female screw which is screwed with the above screw on the inner peripheral wall surface of a cylindrical body is symmetrically fitted to a screwed steel pipe, the steel pipe is horizontally supported. Means, and a chuck mechanism provided opposite to the end face of the steel pipe to be supported by the support means,
The chuck mechanism has a plurality of claws, and each of these claws
The outer wall surface is an arc surface corresponding to the inner peripheral wall surface of
The socket is fixed on the steel pipe by pressing each of the claws of the chuck mechanism against the inner peripheral wall surface of the socket, thereby centering the socket with respect to the steel pipe. Wherein the socket is fitted to the screw portion of the steel pipe by relatively rotating and approaching the steel pipe and the socket. 2. A tapered male thread on the outer peripheral surface of the end of the tubular body.
Screw on the inner peripheral wall of the cylindrical body
Socket with a symmetrical tapered female screw
In socket automatic screw fitting device for coupling-screwed, and a support means for supporting the steel tube horizontally, a chuck mechanism provided by the end surface facing the steel pipe to be supported by the support means, said support
Rotating the steel pipe supported by means and / or the chuck mechanism.
Driving means for rotating the steel pipe and the chuck mechanism relative to each other.
Manner and a drive means for approaching the chuck mechanism has a plurality of claws, the outer peripheral wall surface of each of these claws the tubular body
Arc surface corresponding to the inner peripheral wall surface and tapered tapered surface
Is formed, each pawl socket automatic screw fitting device being characterized in that it presses against the inner peripheral wall surface of the socket configured to be fixedly supporting the socket.