JPS5973251A - Auxiliary clamping device for steel pipe cutting machine - Google Patents

Abstract

PURPOSE:To make it possible to relieve chips bit by clamping rolls irrespective of the size of the space between the clamping rolls, by constituting a hydraulic cylinder for pipe clamping arms with a large diameter chamber and a small diameter chamber, and as well by fitting a floating piston in the large diameter chamber. CONSTITUTION:A cylinder 14 for actuating arms 8 for clamping a pipe P, is constituted with a large diameter chamber 13 and a small diameter 14. A floating piston 15 is fitted into the large diameter chamber 13 and a piston 10 is fitted in the small diameter chamber. The pipe P is clamped between a pair of devices which are opposed to each other under the condition in which hydraulic pressure is applied such that the floating piston and the piston leave away from each other in the case of the pipe having a small diameter, but they approach together in the case of the pipe having a large diameter. In both cases, when chips are bit by clamping rollers 4, the arms 8 are temporarily set free, due to the provision of relief valves 18, and then clamp the pipe again.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an auxiliary clamp device for a steel pipe cutting machine□. More specifically, the present invention relates to an auxiliary clamp device that is disposed near the cutting position of a pipe to be cut and is used to hold pipe ends and the like.

In such an auxiliary clamp device, the present invention is designed to prevent flying chips from being caught between the clamp roller and the steel pipe while clamping and supporting the steel pipe to be cut.
Regardless of the distance between the clamp rollers, which are adjusted in two stages (large diameter and small diameter) at a distance of 70 m*, each clamp roller is individually and instantaneously retreated and restored to remove the trapped chips and remove the steel pipe. The purpose is to prevent damage. Furthermore, the clamping state of the steel pipe by the clamp rollers should not be changed to prevent cutting vibrations that may cause the blade of the carbide saw blade to spill. The purpose is to

By the way, when the steel pipe to be cut is supported by clamp rollers placed at a curved surface near the cutting part, it is conceivable to change the roller interval in two stages at the stroke end of the hydraulic cylinder, corresponding to large diameter pipes and small diameter pipes. . At this time, the biting of chips when the roller spacing is small can be avoided by using pressure oil relief. If the spacing between the cutting rollers is large, it will not be possible to avoid chips from getting caught, which will cause dents in the cut tube and reduce its commercial value, which is a problem. there were.

The present invention was invented to solve these problems, and its structure and operation will be described as follows. That is, it is equipped with a pair of upper and lower arms that are swingably supported in the middle, a clamp roller is attached to the tip of each arm to support the pipe to be cut, and a hydraulic pressure roller is attached to the rear end to adjust the opening degree. The cylinders are directly connected. A pair of upper and lower arms are arranged to face each other on the left and right with the tube to be cut as the center.

The cylinder chamber of the hydraulic cylinder is composed of a large diameter chamber and a small diameter chamber, and a 70-ring piston is fitted in the large diameter chamber. The rod side oil chamber of the small diameter chamber and the floating piston operating chamber of the large diameter chamber are connected by a branch pipe, so that the piston connected to the arm and the 70-ring piston are operated in a direction toward each other. are doing. Further, the oil chambers on the opposite side of the rod-side oil chamber in the small diameter chamber are connected to the same hydraulic power source so that both pistons are operated in the direction of separation.

Preferred embodiments in which the configuration of the invention described above is actually implemented will be described below with reference to the drawings.

FIG. 1 shows a tube cutting device equipped with the auxiliary clamping device of the present invention. Reference numeral 1 denotes a pipe rotating clamp device which grips and rotates the pipe P to be cut with a plurality of segments (not shown), and cuts the pipe P along a cutting line 2a with a carbide saw blade 2. Reference numeral 6 denotes an auxiliary clamp device according to the present invention, which holds the pipe P with an idling type clamp roller 4. Reference numeral 5 denotes a saw blade head, which is movable on a rail 7 provided on a cutting machine frame 6 as shown by arrow a in FIG.

Referring to FIG. 3, reference numeral 8 denotes an arm of the auxiliary clamping device 3, whose intermediate portion is swingably supported by a pin 8a.

The clamp roller 4 is attached to the tip of this arm 8, and the other end of the arm 8 is provided with a hydraulic cylinder 9. 1o is a piston, and the rod 1 of the piston 1o
0a is a sliding block 11 attached to the end of the arm 8
It has been pinned to 12. The cylinder chamber is composed of a large diameter chamber 13 and a small diameter chamber 14. A floating piston 15 is fitted into the large diameter chamber 13, and the piston 10 slides within the small diameter chamber 14. Once this piston 1° comes into contact with the cylinder block 16, it cannot move any further, so this determines the distance between the pair of clamp rollers 4.4.

The 70-ring piston 15 slides a short stroke within the large diameter chamber 13. 15a is floating piston 1
Floating piston working chamber provided at the top of 5, 15
1] is a side chamber of the floating piston 15, and the oil passage 15
It communicates with the small diameter chamber 14 by C. 10b is a rod-side oil chamber formed on the rod 10a side of the piston 10.

The rod side yth chamber 10b and the 70-ring piston working chamber 15a are connected by a branch pipe 17.

The pipe line 17 has a relief valve 18 and a pilot check valve 1.
9, it communicates with the hydraulic pump P via an electromagnetic switching valve 20. On the other hand, the small diameter chamber 14 also communicates with the hydraulic pump P via an IJ valve 18, a pilot check valve 19, and an electromagnetic switching valve 20. 21 is a pressure reducing valve.

Reference numeral 22 denotes a hydraulic cylinder for moving the frame, by which the frame 26 slides on a rail 24 provided on the cutting machine frame 6. As shown in Fig. 5, the upper part of the frame 23 has a frame support roller 25 attached to the cutting machine frame A.
Move with support and guidance.

26 is a frame clamp device for fixing the frame 23. As shown in FIG. 6, the frame 26 and the rail 24, which are sandwiched between the cylinder member 27 and the piston member 27 having a pressure oil supply/discharge port 27a, are tightened by the spring force of the disc spring 28, and the pressure oil flows into the oil chamber 29. When fed, the frame 23 is free with respect to the cutting machine frame 6.

Now, while cutting a small diameter steel pipe, if flying chips get caught in the clamp roller 4 (arrow b in Figure 3), the arm holding pressure oil is released by the IJ valve 18, and the chips are removed. pass. After drying and removing chips, the pressure reducing valve 21 → the (a) position of the switching valve 20 → the pilot check valve 1
Pressure oil is replenished at step 9, and the clamp roller 4 is instantly restored to its original state.

Next, the case of holding a large diameter pipe will be described. The solenoid valve 20 is switched to the (b) position by a command signal from a control device (not shown). Then, the pressure oil flows from the pressure reducing valve 21 → the (b) position of the switching valve 20 → the pilot check valve 19 →
It flows through the pipe line 17 into the rod side oil chamber 10b of the small diameter chamber 14 and the 70-ring piston working chamber 15a of the large diameter chamber 13. Then, the piston 10 and the 70-ring piston 15 are operated in the direction of approaching each other, and the distance at which the piston 10 connected to the arm 8 should hit the floating piston 15 to support the large diameter pipe P of the clamp roller 4 is determined. do. Note that the 70-ring piston 15 has a large diameter chamber 13.
Since it is fitted inside, it operates before the arm connecting piston 10 due to the pressure difference.

When cutting chips are caught on the clamp roller 4 during cutting of a large diameter steel pipe, the arm 8 rotates around the pin 8a, and the arm connecting piston 10 pushes the floating piston 15. Then 7
The pressure oil in the piston working chamber 15a is pushed out, and a part of it flows into the rod side chamber 10b, but the rest is blown off by the relief valve 18 and passes through the chips. Immediately, pressure oil is replenished into the 70-ring piston working chamber 15a through the path of the pressure reducing valve 21→(b) of the switching valve 20→pilot check valve 19, and the floating piston 15 pushes back the piston 10 due to the pressure difference, and the clamp roller 4 to be restored.

When changing the roller spacing of the clamp rollers 4, after changing the roller spacing at the retracted position, the frame 23 is moved by the hydraulic cylinder 22 to a position where the rollers 4 abut and hold the pipe P, and the frame clamp device 26 cuts the pipe P. Fix it to the machine frame B. Note that the upper member of the frame 23 is the frame 2
A rail 25a, which is integrally formed in each frame 3, is in contact with the frame support roller 25 to prevent vibration. Further, the rod guide 30 is in sliding contact with the piston rod 10a, and similarly prevents vibration.

As described above, according to the present invention, when the auxiliary clamp device clamps and cuts the steel pipe to be cut, even if flying chips get caught between the clamp roller and the steel pipe, the clamp roller is instantly retracted to remove the chips. Let it pass and restore it immediately, so
Damage to steel pipes due to chips can be prevented.

Also, since the clamping condition of the steel pipe does not change during clamping,
Steel pipes can be cut efficiently with a carbide saw blade without causing cutting vibration.

[Brief explanation of drawings]

FIG. 1 is a plan view of a tube cutting device equipped with an auxiliary clamp device according to the present invention. FIG. 2 is a front view of the auxiliary clamp device. FIG. 5 is an enlarged front view (partially cut away) of only one side of the auxiliary clamp device according to the present invention. FIG. 4 is a view taken along the line IV-IV in FIG. 6. FIG. 5 is the same <VV sectional view. FIG. 6 is the same <Vl-Vl sectional view. FIG. 7 is a hydraulic circuit diagram. In the figure; P Pipe to be cut 1 Pipe rotating clamp device 2 Carbide saw blade 2a Cutting line 3 Auxiliary clamp device 4 Clamp roller 5 Saw blade head 6 Cutting machine frame
7 Rail 8 Arm 8a Pin 9 Hydraulic cylinder 10 Piston 10a
Piston rod 10b Rod side oil chamber 11
Sliding block 12 Bin 13 Large diameter chamber
14 Small diameter chamber 15 Floating piston 16 Cylinder block 15a Floating piston working chamber 15b (of floating piston) side chamber 15C oil passage 17 Branch pipe 18 Relief valve 19
Pilot check valve 20 Solenoid switching valve 21
Pressure reducing valve 22 Hydraulic cylinder 23 Frame 24 Rail 25 Frame support roller 26 Frame clamp device 27
Cylinder member 28 Disc spring 27 Piston member 29 Oil chamber 30 Long guide and above Applicant Sumitomo Heavy Industries, Ltd. Sub-agent Patent attorney Isamu Ohashi 5vA 25a Figure 6 Figure 7

Claims (1)

[Claims] A pair of upper and lower arms are arranged to face each other on the left and right, and the intermediate part is swingably supported, a clamp roller is freely supported at the tip, and a hydraulic cylinder is disposed at the rear end. Consisting of a large diameter chamber and a small diameter chamber, a floating piston is fitted in the large diameter chamber, and the rod side oil chamber on the small diameter chamber side and the floating piston operating chamber in the large diameter chamber are connected to the arm by a branch pipe. The piston and the 70-ring piston are operated in directions that approach each other, and the opposite side of the rod side oil chamber of the small diameter chamber is connected to the same hydraulic power source so that both pistons are operated in opposite directions. Auxiliary clamp device for steel pipe cutting machine.