JPH04210318A - Method for precise processing of pipe member - Google Patents

Abstract

PURPOSE:To shear cut pipe members with diversified inner radii with sharp cut section by arranging an expandable core metal piece within the space between a movable blade and a fixed blade, inserting a pipe member into the space between the contracted core metal piece and the respective blades, and fixing the pipe member in the expanded condition of the core metal piece. CONSTITUTION:There is arranged in a movable blade 3 a core metal piece 5 in a contracted condition which consists of a wedge 8, an expandable ring 7 which is composed of a plurality of pieces, and a hydraulic cylinder 12 to move the wedge 8 in the axial direction. A similarly composed core metal piece 6 is radially contracted and inserted in the end of a pipe member P in advance. Then, the pipe member P is inserted into a guide hole 21 by a member feeding means 23, and the core metal piece 5 is brought into contact with the core metal piece 6. This arrangement allows the pipe member P to pass through a fixed blade 4, then through the space between the core metal piece 5 and the movable blade 3, and the tip of the pipe member is brought into contact with a recessed part 10 and positioned. Then, the pipe member P is fixed by expanding the core metal pieces 5,6 by means of the cylinders 12, 17 respectively and cut.

Description

[Detailed description of the invention]

[00011

[Industrial Field of Application] The present invention relates to a precision shearing method for pipe materials. BACKGROUND OF THE INVENTION When precisely shearing pipe materials, it is essential to use a metal core to reduce deformation such as crushing of the cut surface. When a fixed core metal is provided in the mold as the core metal, there is a limit to the length of the material that can be subjected to shearing. As a way to solve this problem,
No. 727 proposes a method of shearing pipe materials using a floating core. [0003]

[Problems to be Solved by the Invention] This prior art provides a fixed core metal on the punch side that fits with the pipe material to be cut,
A floating mandrel facing the fixed mandrel is placed in a pipe material, and cutting is performed along the surfaces where the fixed mandrel and floating mandrel come into contact with each other. However, pipe materials generally have very large variations in internal diameter due to manufacturing problems. For this reason, in actual shearing, if only the prior art is applied, the core metal may not be able to be inserted into the pipe, or conversely, a large gap will be created between the core metal and the pipe material, reducing the effect of using the core metal. There was a problem that they were not performing to their full potential. [0004]

[Means for Solving the Problems] The present invention was developed through research in order to solve the above-mentioned problems, and its purpose is to closely fit pipe materials with varying inner diameters. The object of the present invention is to provide a method capable of shearing. [0005] In order to achieve the above object, the present invention provides a method for shearing pipe material using a core metal, which includes a wedge, a plurality of expansion/contraction ring bodies located on the outer periphery of the wedge, and means for moving the wedge in the axial direction. Using an expandable core metal consisting of a movable blade and a fixed blade, the core metal is placed inside the movable blade and the fixed blade, a pipe material is inserted with the diameter reduced, and then the expansion ring body is expanded by moving the wedge. The diameter of the expansible ring is brought into close contact with the pipe material, and in this state, the movable blade is operated to perform shearing, and the wedge is returned to reduce the diameter of the expandable ring body and discharge the off-cut material. [0006] (Example) Examples of the present invention will be described below with reference to the accompanying drawings. Figure 1 shows an overview of the present invention, and Figure 2 shows a core metal used in the present invention. The punch is fixed to a punch holder (not shown) and is moved up and down by a press ram. 2 is a die arranged and fixed on the side of the punch L, and has a guide hole 21 for the pipe material P. [0007] ]3 is the front side of the punch 1, that is, the die 2
A ring-shaped movable blade 4 is fitted and fixed in a recess 10 provided on the side opposite to the punch 1.
These movable blades 3 and 4 have a cross-sectional shape that matches the outer contour of the pipe material P, and cut the opposing surfaces. The blades shear the pipe material. [0008] Reference numeral 5 denotes a first core metal that can be expanded and contracted in the radial direction, and 6 is a second core metal that can be expanded and contracted in the radial direction, which are housed in the pipe material P. The first core bar 5 and the second core bar 6 each include an expansion ring body 7, a wedge 8 disposed on the inner diameter side of the expansion ring body 7, and a means 9 for moving the wedge 8 in the axial direction by fluid pressure. It is equipped with Compressed air or hydraulic pressure is suitable as the fluid pressure. [0009] In detail, the expansion/contraction ring body 7 has an outer surface shape corresponding to the inner surface shape of the pipe material P (cylindrical in this embodiment).
It consists of two or more divided blocks 70 having
Grooves are formed at appropriate locations on the outer periphery as necessary, and O-rings 71 for fixing the divided blocks are attached to the grooves. The inside of the expansion/contraction ring body 7 has a tapered shape that matches the wedge 8. FIG. 2 shows an example of a wedge 8 and an expansion ring body 7. In (a), the expansion/contraction ring body 7 is split in half, and the wedge 8 has a rectangular cross section. In (b), the expansion/contraction ring body 7 is split in half, and the wedge 8 has a circular cross section with a portion of parallel surfaces. In addition, the expansion ring body 7
is not limited to two divisions, but may be three, four, or more divisions. [00101 The expansion/contraction ring body 7 of the first core metal 5 is the movable blade 3
A guide hole 11 communicating with the back side of the punch is provided at the center of the bottom of the recess 10.
is provided. On the other hand, as a means 9 for moving the wedge 8 in the axial direction, a fluid pressure cylinder 12 is fixed to the back of the punch, particularly concentrically with the movable blade 3. The fluid pressure cylinder 12 has a piston 13, and a piston rod 130 coupled to the piston 13 passes through the guide hole 11 to reach the expansion ring body 7, and is inserted into the rear end of the wedge 8 inserted into the expansion ring body 7. connected. In this example, wedge 8
By pulling, the expansion ring body 7 is moved in a direction perpendicular to the pipe material axis (parallel to the shearing direction), and a fluid supply/discharge port 120 is provided on the rod side, and a conduit 15 connected to this is provided. is connected to a fluid pressure source (compressed air source or hydraulic pressure source) via a switching valve 150. A spring 6 is disposed on the piston side, and is configured to advance the piston 13 and push in the wedge 8 under normal conditions. [0011] In the second core bar 6 as well, the means 9 for moving the wedge 8 in the axial direction is the fluid pressure cylinder 17, but this fluid pressure cylinder 17 is coaxial with the expansion ring body 7. Moreover, it has an outer diameter smaller than the diameter when expanded, and is connected to the expansion/contraction ring body 7 via a connecting portion 173 at the tip so as not to move in the relative axial direction. The fluid pressure cylinder 17 has an O-ring 174 attached to its outer periphery that contacts the inner surface of the pipe material P, a piston 18 disposed inside, and a piston rod 1 connected to the piston 18.
80 is connected to the rear end of the wedge 8 in the expansion ring body 7. In this embodiment, the expansion/contraction ring body 7 is expanded in diameter by pushing the wedge 8. Therefore, a fluid supply/discharge port 170 is provided on the piston side, and a flexible hose 19 is connected to this. It is led out from the end of the pipe material P and connected to a fluid pressure source (compressed air source or hydraulic pressure source) via a switching valve] 790. A spring 22 is disposed on the rod side, and is configured to move the piston 18 backward in a normal state and pull the wedge 8. If the flexible hose 19 is made sufficiently long, it can be used with long pipe materials, and even if the length of the pipe material changes, it can be easily handled. [0012] In addition, in the drawings, 23 is a material feeding means arranged at the rear of the die 2, and in this embodiment, a roller is used. This material feeding means may have the function of applying an axial compressive force to the pipe material. or
A window hole may be provided in the die 2 at the rear of the fixed blade 4, and a pressing member may be disposed in the window hole to apply pressure to the pipe material from a direction perpendicular to the axis when the punch plate is lowered, thereby applying a restraining force. 24
is a stripper means, and in this embodiment, an air bushing method is adopted in which a guide hole 240 communicating with the bottom between the movable blade 3 and the expansion/contraction ring body 7 is provided, and this guide hole 240 is connected to an external compressed air circuit. However, it is not limited to this. [00131 FIGS. 3 to 5 show the pipe material P according to the present invention.
It shows the process of shearing. First, in processing, as shown in FIG. 3, the movable blade 3 of the punch 1 and the fixed blade 4 of the die 2 are positioned so as to concentrically contact each other, and the diameter of the core metal 5 in the movable blade 3 is reduced. Further, the core metal 6 is reduced in diameter and inserted into the end of the pipe material P in advance, and in this state, the material feeding means 23 is driven to insert the pipe material P into the guide hole 21. Core metal 5
．． The diameter reduction of cylinder 6 is performed by operating the switching valves 150 and 190 shown in FIG. 1 and communicating the supply and discharge ports 120 and 170 of the cylinders 12 and 17 to the low pressure side, respectively. When the pressure medium is compressed air, the supply/discharge ports 120, 170 are communicated with the atmosphere. This causes the pressure chamber of the cylinder 12.17 to be under low pressure, so that the spring 12.22 causes the piston 13.18 to
is moved. On the movable blade 3 side, a piston rod 130 with a wedge 8 connected to its tip advances in the direction of the fixed blade, and the wedge 8 advances in the direction of enlarging the taper hole of the expansion/contraction ring body 7, so that the expansion/contraction ring body 7 contracts in diameter. Further, on the fixed blade 4 side, the piston rod 180 retreats, and the wedge 8 connected to the tip of the piston rod 180 retreats in the direction of enlarging the taper hole of the expansion ring body 7, so the diameter of the expansion ring body 7 is reduced, and the O-ring 174
comes into contact with the inner diameter of the pipe material P and is stopped by frictional force. [0014] Since the outer diameter of the core metals 5 and 6 is reduced by the above operation, even if the inner diameter of the pipe material is smaller than the specified value due to variations during manufacturing, the core metals 5 and 6 can be inserted smoothly. The core metal 6 on the fixed blade 4 side has an O-ring 17 on the inner surface of the pipe material P.
4 are in contact with each other, they move together with the feeding of the pipe material P, and the expansion and contraction ring body 7 is positioned by coming into contact with the expansion and contraction ring body 7 on the movable blade side. The pipe material P passes through the fixed blade 4, passes through the gap between the diameter-reduced core metal 5 and the movable blade 3, and is positioned with its tip touching the bottom of the four parts 10. [00151] Next, the switching valves 150 and 190 are operated to send the pressure medium into the cylinder 12.17 as indicated by the arrow in FIG. As a result, the pressure in the pressurizing chamber increases, and the piston 13
．． 18 is moved against the spring force of the spring 16.22, the piston rod 130 and the wedge 8 are pulled on the movable blade 3 side, and the screw 1-in rod 180 and the wedge 8 are pushed in on the fixed blade 4 side. Since the moving direction of the wedge 8.8 is in the direction of decreasing the diameter of the tapered hole, the expansion/contraction ring body 7, which is divided in the circumferential direction, moves in the radial direction, and the outer circumferential surface comes into close contact with the inner surface of the pipe material P. The expanded diameter dimension of the expansion ring body 7 is variable depending on the movement stroke of the piston 13.18, and therefore, even if the inner diameter of the pipe material P is larger than the specified value, the core bar 5.6 can be reliably brought into close contact with the pipe material P. be able to. [0016] The cylinders 12.17 are then as described above.
A press ram (not shown) is moved while the press is held under pressure. As a result, the punch 2 descends as shown in FIG. 5, and the movable blade 3 descends while contacting the fixed blade 4, so that the pipe material P is sheared. Since the outer surface of the pipe material P is in contact with the movable blade 3 and the fixed blade 4, and the inner surface is in close contact with the core metals 5 and 6 whose diameter has been expanded, the pipe material P is precisely sheared without deformation of the cut surface. [0017] When the movable blade 3 reaches its lower limit, the pressure chamber of the cylinder 12 on the fixed blade side is made conductive to the low pressure side as shown in FIG. As a result, the piston 13 and the piston rod 130 move forward by the spring force of the spring 16, and the wedge 8 is pushed in, so that the expansion/contraction ring body 7 is reduced in diameter and separated from the inner surface of the sheared off-cut material P'. After that, when the stripper means 24 is operated, the off-cut material P'' is discharged to the outside from the discharge recess 25 of the die 2.The cylinder 17 on the remender side also reduces the pressure in the pressurizing chamber. piston 18 and piston rod 180
is retracted, and the wedge 8 is compressed by the force 1, so that the expansion and contraction ring body 7 contracts in diameter so as to be separated from the inner surface of the Remender side member. Therefore, the O-ring 17 is attached to the inner surface of the core bar 6 and the mender side material P.
4, and the Remender side member P is in a state where it can be easily moved in the axial direction. [00181] Next, when the bunch 1 is returned to return to the state shown in FIG. 3, the material feeding means 23 is operated to feed the pipe material P. By repeating the above operations, the pipe material is continuously sheared. In order to further improve the cut surface, when the state shown in Fig. 4 is reached, the material feeding means 23 should be activated to apply an axial compressive force, or a restraining force should be applied from a direction perpendicular to the axis of the pipe material. good. [0019]

Effects of the Invention According to the present invention as described above, an expandable core metal consisting of a wedge, a multi-split expandable ring body located on the outer periphery of the wedge, and a means for moving the wedge in the axial direction is used, and the inside of the movable blade is Place the core metal inside the fixed blade and insert the pipe material with its diameter reduced, then move the wedge to expand the diameter of the expansion ring body and bring it into close contact with the pipe material, and move it in this state. The blade is activated to shear, and the wedge is returned to reduce the diameter of the expansion ring and discharge off-cut material, making it possible to shear pipe materials with large variations in internal diameter into clean cuts. You can get the same effect.

[Brief explanation of the drawing]

[Fig. 1] A cross-sectional view showing an overview of the precision shearing method for pipe materials according to the present invention and the equipment used to carry out the method.

[Fig. 2] A perspective view showing an example of the core metal in the present invention.

[Figure 3]
A sectional view showing the first stage of the precision shearing method for pipe material according to the present invention

[Fig. 4] A cross-sectional view showing the second stage of the precision shearing method for pipe material according to the present invention.

[Fig. 5] A cross-sectional view showing the third stage of the precision shearing method for pipe material according to the present invention.

[Fig. 6] A cross-sectional view showing the fourth stage of the precision shearing method for pipe material according to the present invention.

[Explanation of symbols]

1... Punch, 2... Dice, 3... Moving blade, 4
... fixed blade, 5.6 ... core metal, 7 ... expansion ring body, 8 ... wedge, 9 ... axial direction moving means, P.
・・Pipe material

[Figure 2]

Claims (1)

[Claims] Claim 1: A method for shearing pipe material using a cored metal, which includes an expandable and contractible cored metal consisting of a wedge, a plurality of expandable and contractible ring bodies located on the outer periphery of the wedge, and means for moving the wedge in the axial direction. The core metal is arranged inside the movable blade and the fixed blade respectively, and the pipe material is inserted with the diameter reduced, and then by moving the wedge, the expansion ring body is expanded in diameter and brought into close contact with the pipe material. , a precision shearing method for pipe material characterized by operating a movable blade in this state to perform shearing, and returning the wedge to reduce the diameter of the expansion ring body and discharge off-cut material.