JPH06246502A - Steel pipe surface cutting machine - Google Patents

Abstract

(57) [Summary] [Purpose] Automatic control of machining is made possible by the steel pipe chamfering machine that makes it possible to greatly simplify the setup change work and the NC in the Z-axis direction and the X-axis direction. [Structure] In this steel pipe chamfering machine, the copying slider of the rotating chamfering tool moving in the Z-axis feeds the differential gear mechanism 17 inward in the direction perpendicular to the Z-axis, that is, in the X-direction. It is moved forward and backward by the screw mechanism and the biasing means 16. The copying roller 8 moves integrally with the copying slider 14, and the biasing means 16 is provided.
The inner surface of the steel pipe 31 is copied while being urged by. The end surface is processed with the inner surface of the steel pipe 31 as a reference by the copying roller 8 and the processing blade 7 that moves as one body.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steel pipe face mill for performing various kinds of end face processing on a conveyed steel pipe on a production line of seamless steel pipes and the like, for example, groove chamfering and end face finishing. Regarding the machine.

[0002]

2. Description of the Related Art Seamless steel pipes are cut into lengths according to their use on the production line. The cut steel pipe is immediately subjected to various end face processing on the production line. There are various types of end face processing such as groove chamfering, inner and outer chamfering, and end face finishing.
It is applied according to the application of the steel pipe.

Tolerances of such steel pipes include outer diameter tolerances, roundness tolerances, and wall thickness tolerances. Especially, the wall thickness tolerance is ± 10
It is large at ± 15%, and the concentricity of the inner and outer diameters is allowed within the wall thickness tolerance. On the other hand, as shown in the example of FIG. 7, the groove processing includes α = 14 ° to 18 °, θ ± 2.5 ° = 30 °, 3
2.5 °, 37.5 °, R = 1.6 ± 0.8, C = about 0.5.

Further, such end face processing is performed according to the pipe forming speed. In order to perform such processing in accordance with the pipe making speed, it is required to increase the efficiency of the steel pipe chamfering machine.
Since it is necessary to carry in / out and attach / detach the steel pipe in a short time according to the pipe making speed, a centripetal type chuck having two claws in the horizontal direction is used as a chuck for grasping the steel pipe. Therefore, chucking is performed on the basis of the outer diameter.

In order to obtain a desired surface shape from the tolerances of the uneven thickness and roundness and the conditions of the above dimensions based on the inner diameter, it is necessary to perform machining according to the inner diameter. In the steel pipe chamfering machine in (1), a system is adopted in which the pipe is fixed and the blade is rotated, and machining is performed according to the inner diameter of the steel pipe. 8 and 9 show a steel pipe chamfering machine according to this conventional method.

The steel pipe 81 is sandwiched by two claws (not shown) that move centripetally horizontally and is held by a chuck of a type that does not rotate. The chamfering tool 84, which is provided with three cutting blades 82, 82 ', and 83 for respectively performing three types of machining and is rotated, is composed of a main body portion 84a and a radial direction moving portion 84b, and both main body portions 84a, 84b are It is movable in one body in the axial direction (hereinafter referred to as the Z-axis direction).

The radial moving portion 84b of the chamfering tool 84
The cutting blade 82 is attached to the. Further, a copying roller 85 having an axis parallel to the Z-axis direction is attached to the radial movement portion 84b in an integral relationship with the cutting blade 82.
The radial moving portion 84b is radially moved by the compression spring 86 (downward in the drawing, hereinafter referred to as X-axis direction) to the main body portion 84.
Stopper 87 that has been pressed from a but has a tapered surface
Is adjusted so that only the length S shown in the drawing moves from the position shown. This moving length S is determined by the stopper 87.
Is adjusted by moving the Z axis in the Z axis direction.

In such a conventional steel pipe chamfering machine, since the copying roller 85 follows the inner peripheral surface of the steel pipe 81, the end surface can be machined on the basis of the inner diameter. According to the above-mentioned conventional steel pipe chamfering machine, even if the chamfered shape is the same, if the inner and outer diameters of the pipe and the wall thickness change, it is necessary to move the chamfering tool to reposition the cutting blade and the copying roller. Yes, and each time, setup work on the machine is required. Further, since this setup change work is manual work and NC control is not naturally performed, interlocking control of the chamfering tool in the Z-axis direction and the X-axis direction cannot be performed.

[0009]

The present invention has been invented in the background as described above, and achieves the following objects.

An object of the present invention is to provide a steel pipe chamfering machine capable of greatly simplifying the setup change work.

Another object of the present invention is to provide a steel pipe chamfering machine which enables automatic control of machining by making NC in the Z-axis direction and the X-axis direction.

[0012]

The present invention adopts the following means in order to achieve the above object.

According to the present invention, the feed table (2) is fed and driven by the first driving means (3), and the chamfering tool (4) is rotatably driven by the rotary drive motor (5) on the feed table (2). ), A chamfering tool (4) for moving the chamfering tool (4) in a right angle direction orthogonal to the feed direction of the feed table (2), and a driving slider for driving the chamfering slider in the right angle direction. A feed screw mechanism (25, 26), a differential gear mechanism (17) for rotating the feed screw mechanism (25, 26), and a biasing force for the copying slider (14) in the perpendicular direction. A biasing means (16), a cutting blade (7) fixed to the copying slider (14) for processing a work (31), and the copying slider (14).
The steel pipe chamfering machine is characterized by comprising a copying roller (8) rotatably fixed to the work roller (31) and capable of contacting the inner peripheral surface of the work (31).

Further, it may be a steel pipe chamfering machine having a driver device (40) for adjusting the pressing force of the copying roller (8) to the work (31) by the urging means (16). .

[0015]

In the steel pipe chamfering machine of the present invention, the copying slider of the rotating chamfering tool that moves in the Z-axis direction is in the direction perpendicular to the Z-axis, that is, inward in the X-direction. It is moved forward and backward by the mechanism and the biasing means 16. The copying roller 8 moves integrally with the copying slider 14 and follows the inner peripheral surface of the steel pipe 31 while being biased by the biasing means 16. By the cutting blade 7 that moves integrally with the copying roller 8, the end surface processing is performed with the inner peripheral surface of the steel pipe 31 as a reference.

[0016]

EXAMPLES Next, examples of the present invention will be described.

Example 1 FIGS. 1 to 4 show Example 1 of the steel pipe chamfering machine of the present invention,
FIG. 1 is a sectional view showing the main part thereof. 2, 3, and 4 are a front view, a plan view, and a side view of the whole, respectively. The base 1 is a base forming a machine body.

A chamfering tool feed base 2 is mounted on the moving surface of the base 1 so as to be movable in the Z axis direction. The chamfering tool feed base 2 is mounted on the Z axis by a Z axis control motor 3 (see FIG. 3). Driven in the direction and controlled by NC. A chamfering tool 4 is rotatably provided on the chamfering tool feed base 2, and the chamfering tool 4 is rotationally driven by a rotary drive motor 5 (see FIG. 3).

FIG. 1 shows the main internal structure of the chamfering tool 4. The main body 4 a (or main shaft) is the main body of the chamfering tool 4. The main body 4a is rotationally driven about the central axis L by the rotational drive motor 5. Projecting portion 6a of rotating body 6 that rotates integrally with main body 4a
The cutting blade 7 is detachably fixed and attached to the. Further, the copying roller 8 is attached to the protruding portion 6a so as to be rotatable.

The rotating body 6 is provided with a screw rod 9 extending in the X-axis direction (radial direction). The non-threaded part of the threaded rod 9 is supported by the bearing 10, and the threaded part is the nut 1.
1 and is screwed. Nut 11
A part of it is fitted in the groove 11a and is movable in the X-axis direction. The nut 11 has a cylindrical portion 11b, and a push rod 12 is inserted and fixed to the tip of the cylindrical portion 11b.

A copying slider 14 is provided on the rotating body 6 so as to surround the threaded rod 9. The copying slider 14 can move in the radial direction with respect to the rotating body 6. The end portion of the copying slider 14 is closed by a closing lid 15, and the closing lid 15 and the flange 12 a of the push rod 12.
A compression spring 16 is interposed between and. After all,
By rotating the head portion 9a at the end of the threaded rod 9, the compression force of the compression spring 16 can be varied.

A differential gear unit 17 is mounted on the chamfering tool 4 integrally with the chamfering tool 4, and the differential gear mechanism 17 is rotated together with the chamfering tool 4. A rotating shaft 18 that rotates about the central axis L of the rotating body 6 is attached to the main body 4a. Bevel gear 19 attached to this rotating shaft 18
The two bevel gears 20 are meshed with each other. This bevel gear 2
The shaft 21 of 0 is rotatably attached to the main body 4a via a bearing 22.

A gear 23 is fixed to one end of the rotary shaft 21. A gear 24 is provided so as to mesh with the gear 23. The gear 24 is rotatably attached to the main body 4a. As described above, the differential gear device 17 includes the rotating body 6,
Rotating shaft 18, main body 4a, bevel gear 19, bevel gear 20, shaft 2
1, a bearing 22, a gear 23, and a gear 24.

A ball screw 25 is provided at the center of the gear 24.
Is passing. A ball nut 26 is interposed between the ball screw 25 and the cylindrical portion 24 a of the gear 24. The ball nut 26 is screwed into the ball screw 25 and is fitted and fixed to the inner peripheral portion 24 a of the gear 24. A small diameter portion 25b having a smaller diameter than the screw portion 25a is formed at one end of the ball screw 25.

The small-diameter portion 25b is a spline shaft and fits into the spline hole 27, and the spline hole 27 is fixed to the hole of the protruding portion 28 integral with the copying slider 14. The spline hole 27 has one end surface 27a, and this one end surface 27a is joined between the thread portion 25a of the ball screw 25 and the end surface 27c at the boundary between the small diameter portion 25b and serves as a stopper surface of the ball screw 25.

The bevel gear 20 faces the central axis L and is
One differential gear unit (not shown) is provided. Two sets of the copying slider 14, the cutting blade 7, and the copying roller 8 are also provided, and the two copying rollers 8 are arranged in axial symmetry. The rotary shaft 18 is rotationally driven by a desired amount under the control of NC via a differential drive mechanism (not shown) arranged at the rear end thereof.

As shown in FIG. 4, the steel pipe 31, which is a workpiece, is sandwiched by a vise having two claws 32 which are orthogonal to the Z-axis direction and move in opposition to each other in the horizontal direction. Claw 32
Is driven by a hydraulic drive device 33. The two claws 32 are linked by a centripetal mechanism (not shown) so that the steel pipe 31 can be set so as to be always coaxial with the central axis L. Various known ones can be applied to the centripetal mechanism.

The work is carried out and carried in by four walking beams that move circularly. The loci (circles) 34a and 34b of the set points of the two walking beams are circumscribed on the central axis L. Two other walking beams are provided next to each of the walking beams, and the loci (circles) 34c and 34d of the set points of the other two walking beams are the loci 34.
It intersects with a and 34b, respectively.

The work can be transferred between two adjacent walking beams to be carried in from the carry-in side position A to the holding position B, and after processing, to be carried out from the holding position B to the carry-out position C. Although various known walking beams can be applied, this structure will not be described in detail here. A driver 40 is arranged above the chamfering tool 4. The driver 40 is a device for rotationally driving the head portion 9 a of the screwed rod 9.

The driver 40 is provided with a slider 41 that can move in two directions and can move in the X and Y axis directions. The movement of the slider 41 in the X-axis direction is driven by the X-axis servo motor 42, and the movement of the slider 41 in the Y-axis direction is driven by the Y-axis drive cylinder 43. When the chamfering tool 4 is stopped, the slider 41 is moved to a predetermined position, and a wrench mounted on the slider 41 is used to move the head 9 of the screwed rod 9 into the head 9.
A is rotated by the motor 44 to drive the threaded rod 9.
This drive moves the nut 11 to optimally adjust the compression force of the compression spring 16.

[0031] Operation of Example 1 Next, the operation of the first embodiment. The steel pipe 31, which is a work cut into an appropriate size on the pipe making line, is carried into the clamping position B by the walking beam, and the hydraulic drive device 33 is driven to clamp the steel pipe 31 with the claw 32 to fix it. Next, when the rotary drive motor 5 is driven, the chamfering tool 4
The main body (or main shaft) 4a rotates about the central axis L. The rotating body 6 and the copying slider 14 rotate together with the main body 4a around the central axis L. Hereinafter, in FIG. 1, the direction toward the central axis L in the X direction is referred to as the inward direction, and the opposite direction is referred to as the outward direction.

The copying slider 14 includes a compression spring 16
Is displaced in the outward direction by the compressive force of
When moving outward together with the protruding portion 28, the end surface 27c of the spline hole 27 comes into contact with the end surface 25c of the screw portion 25 of the ball screw 25. Since the main body 4a and the rotary shaft 18 are not rotationally driven relatively, the gear 24 is not rotating and the ball screw 25 is not displaced in the X direction due to the structure of the differential gear mechanism 17.

Therefore, the displacement of the copying slider 14 in the outward direction stops. Therefore, the copying roller 8 integrated with the copying slider 14 stops at a radial position separated from the central axis L by a certain distance. The radial position is shown by a two-dot chain line in FIG. The position of the copying roller 8 in this state is indicated by A.

Next, the differential gear unit 17 is operated while continuing the rotation of the main body 4a. The rotating shaft 18 is rotated relative to the main body 4a by a differential drive mechanism (not shown). The bevel gear 20, the shaft 21, the gear 23, and the gear 24 are sequentially rotated. The cylindrical portion 24a is rotated integrally with the gear 24, and the ball nut 26 fixed to the cylindrical portion 24a is rotated. The ball screw 25, which is screwed into the ball nut 26 via a ball, cannot rotate because one end of the ball screw 25 is blocked by the spline hole 27 fixed to the hole of the protrusion 28 integrated with the copying slider 14. . Therefore, the ball screw 25 is moved in the axial direction of the screw, that is, the X-axis direction (radial direction), and the ball screw 25 is moved in the radial outward direction.

With the outward movement of the ball screw 25, the force of the compression spring 16 causes the copying slider 14 to be displaced outward. Eventually, the copying roller 8 starts to hit the inner peripheral surface of the steel pipe 31. The outer peripheral surface of the steel pipe 31 is set coaxially with the central axis L with a fairly good accuracy, but the inner peripheral surface of the steel pipe 31 is
Eccentricity is within ± 15% of the wall thickness of 1. Therefore, the rotary shaft 18 is rotated a little further, and the differential gear device 17 is operated to displace the ball screw 25 outward. Since the copying roller 8 elastically contacts the inner peripheral surface of the steel pipe 31 by the force of the compression spring 16, the copying roller 8 comes into contact with the entire inner peripheral surface of the steel pipe 31 to rotate. The position of the copying roller 8 in this state is shown by a chain double-dashed line B.

Next, the control motor 3 is driven to move the feed base 2 and the feed main body 4a in the Z-axis direction. The copying roller 8 is advanced to the position shown by the solid line C, and a predetermined end surface processing is performed by the cutting blade 7. The rotary shaft 18 is rotated in the reverse direction, the copying roller 8 is sent to the position indicated by the chain double-dashed line D, and the first NC control motor 3 is rotated in the reverse direction to return it to the position shown by the original double-dotted chain line A.

When the operation of retracting the copying roller 8 from the position shown by the solid line C in the axial direction is performed, the gap d shown in FIG. 1 is provided between the spline groove 27 and the end surface 27a of the ball screw 25.
And place it. If such a gap d is provided, when the copying roller 8 retreats and separates from the inner peripheral surface of the tube, the copying roller 8 and the copying slider 14 are displaced outward by the width of the gap d, but the ball screw 25. Does not move any further because it acts as a stopper.

When the inner surface cannot be copied due to the small diameter of the pipe, the copying gear 14 is not received by the copying roller 8 by the differential gear device 17 but by the ball screw 25 so that the position toward the outside of the cutting blade 7 is fixed. Control and perform cutting. The operation of the copying roller 8 and the cutting blade 7 has been described only for one set, but the other set of the copying roller 8 and the cutting blade 7 are also arranged axially symmetrically and perform the same operation.

By driving the differential gear mechanism to drive the rotary shaft 18, the copying roller 8 can be arbitrarily displaced in the radial direction. Further, by moving the copying roller 8 and the cutting blade 7 in this manner, it is possible to cope with an arbitrary change of the outer diameter and the inner diameter of the steel pipe 31 without exchanging the tool or adjusting the clamp position of the cutting blade. Furthermore, if the degree of uneven wall thickness is individually measured while on the pipe making line and the measured value is entered into the software, tool replacement / cutting blade position is possible even if the wall thickness changes. It is also possible to automate the end face processing without adjustment.

The compression force of the compression spring 16 is adjusted as follows. When the chamfering tool 4 is stopped at a fixed position, the slider 41 is moved to a predetermined position, and the head 9a of the threaded rod 9 is rotated by the motor 44 with a wrench (not shown) mounted on the slider 41 to screw the screw. The attached rod 9 is driven. This drive moves the nut 11 to optimally adjust the compression force of the compression spring 16.

Other Embodiments of Tool The steel pipe chamfering machine of the present invention is not suitable for the end face machining of the plain end shown in FIG. Therefore, a special chamfering tool 100 used exclusively for processing the end face of the plane end will be briefly described with reference to FIGS. 5 and 6 for reference.
In FIG. 5 and FIG. 6, two copying sliders 102, 1 repelling in opposite directions by one compression spring 101.
03 is used. A copying roller 104 for copying the inner surface is attached to the inner copying slider 102, and a copying roller 105 for copying the outer surface is attached to the outer copying slider 103.

Cutting blades 106 and 107 for plane end processing are attached to both copying sliders 102 and 103.
The outer copying slider 103 repels inward in the X direction, and the inner copying slider 102 repels outward in the X direction.
Therefore, the inner copying roller 104 follows the inner peripheral surface of the steel pipe 31, and the outer copying roller 105 follows the outer peripheral surface of the steel pipe 31. Therefore, the inner processing is processed with the inner peripheral surface as a reference, and the outer processing is processed with the outer peripheral surface as a reference.
When performing this processing, the chamfering tool 100 is replaced.

Other Embodiments Some embodiments have been described above, but the present invention is not limited to the above embodiments, and various design changes can be made within the scope of the constitution and operation of the present invention. it can. For example, by converting the material pipe information such as pipe diameter, wall thickness, material, etc. and positioning information into NC and inputting it into the program software including the operation command, the rotation speed of the spindle 4a and the feed speed of the chamfering tool 4 can be changed by NC. Can be controlled. In addition, the variable pitch feed is performed and the load is controlled so that the cutting area is constant, so that the feed speed is controlled when the blade is biting or the finish feed before the dwell.

Further, in order to freely select the origin, the automatic tool changing position, and the manual maintenance work position in the automatic machining operation in a wide range, the spindle head (spindle 4
It is desirable to have a large Z-axis feed stroke in a).

[0045]

According to the steel pipe chamfering machine of the present invention, since it is not necessary to change the position of the cutting tool for each pipe diameter, the setup change work can be simplified. Further, since the movement of the blade in the radial direction can be controlled while copying the inner surface of the pipe by the copying roller, automation of end face processing can be achieved.

[Brief description of drawings]

FIG. 1 is a sectional view showing a main part of a steel pipe chamfering machine according to a first embodiment of the present invention.

FIG. 2 is a front view showing the entire embodiment 1 of the steel pipe chamfering machine of the present invention.

FIG. 3 is a plan view of FIG.

FIG. 4 is a side view of FIG.

FIG. 5 is a sectional view showing a reference example of a steel pipe chamfering machine.

FIG. 6 is a side view of FIG.

FIG. 7 is a cross-sectional view showing a typical groove processing example by a steel pipe chamfering machine.

FIG. 8 is a front sectional view showing a conventional steel pipe chamfering machine.

FIG. 9 is a side view of FIG.

FIG. 10 is a cross-sectional view showing another example of groove processing by a steel pipe chamfering machine.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Base 2 ... Chamfering tool feed base 3 ... Z-axis control motor 4 ... Chamfering tool 5 ... Rotation drive motor 7 ... Cutting blade 8 ... Copying roller 14 ... Copying slider 16 ... Compression spring 17 ... Differential gear unit 30 … Second motor

Claims (2)

[Claims] 1. A feed table (2) driven by a first driving means (3), and a chamfering tool (4) rotatably driven by a rotary drive motor (5) on the feed table (2). A copying slider (1) in which the chamfering tool (4) is moved in a direction perpendicular to the feed direction of the feed table (2).
4), a feed screw mechanism (25, 26) for driving the copying slider in the perpendicular direction, and a differential gear mechanism (17) for rotating the feed screw mechanism (25, 26). A biasing means (16) for biasing the copying slider (14) in the perpendicular direction, and a work (31) fixed to the copying slider (14).
A steel pipe characterized by comprising a cutting blade (7) for machining a workpiece and a copying roller (8) rotatably fixed to the copying slider (14) and capable of contacting an inner peripheral surface of a work (31). Chamfer. 2. The steel pipe chamfering machine according to claim 1, further comprising a driver device (40) for adjusting a pressure applied by the biasing means (16) to the work (31) of the copying roller (8). .