DE2814438A1 - METHOD AND DEVICE FOR CUTTING A TUBE - Google Patents

Description

DR.-ING. DIPL.-INS. hi. 3C. OlPL.-PKYj. D "?. DIPL.-PHYS.

HÖGER - LEGAL RIGHTS - GSRIESSBACH - HAECKER

PATENT LAWYERS IN STUTTGART

A 42 808 m Applicant: Paul Werner Vormbaum

m - 168 14-7th Street

March 29, 1978 New Doornfontein

Johanne sbur g Transvaal Republic of South Africa

description

Method and device for cutting a pipe

The invention relates to methods and devices for trimming of a pipe with a cutting tool. The invention is particularly suitable for the formation of pipe sections, as used in the manufacture of pipe bends.

Pipe bends, e.g. for ventilation or air conditioning purposes, are often made from specially shaped sections of pipe that are connected to each other and a Form the curvature of the desired radius and angle. The outline of each pipe section is usually drawn on a metal sheet o. The like. Projected or recorded, after which the sheet is usually cut by hand and then into a pipe of the desired diameter is closed. This process is time consuming and especially costly in countries where where labor costs are high.

It is the object of the invention to provide a simple and improved method for cutting pipes and for implementation indicate suitable devices for the procedure.

According to the invention, a method for trimming a pipe with a cutting tool is characterized by the following method steps: the cutting tool is in the cutting position applied to the pipe and the pipe and the cutting tool are rotated relative to each other in this way.

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that the pipe is cut in a first plane which forms a first, acute angle with the longitudinal axis of the pipe includes.

In a preferred embodiment of the invention, the Tube rotated about a first axis which intersects the longitudinal axis of the tube and with this axis a first, predetermined Includes angle. In an alternative embodiment of the invention, the cutting tool is a first Rotated axis which intersects the longitudinal axis of the pipe and includes a first, predetermined angle with this. Furthermore, according to the invention, the first, predetermined angle can be equal to the first acute angle. _

According to the invention it is further provided to form a flange on the cut end of the pipe. To this end a flange-forming tool is attached to the trimmed end of the tube, followed by the tube and the tool rotated relative to each other in such a way that an outwardly protruding flange is formed at the trimmed end of the pipe, which is on the first level. Again, either the tube or the tool forming the flange around the first Axis can be set in rotation.

Said, first acute angle is preferably approximately 7.5. Because of this angle it is relatively easy to Manufacture pipe bends at angles of 15 °, 30 °, 45 °, 60 ° and 90 °.

According to the invention, a pipe cutting device is further provided which comprises a cutting tool, as well as means, in order to place this cutting tool in the cutting position on the pipe.

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zen, and further means to cut the pipe and the cutting tool to rotate relative to each other in such a way that the pipe is cut along a first plane which coincides with the longitudinal axis of the tube encloses a first, acute angle. Either the cutting tool or the pipe can be moved around a first axis are rotated, which intersects the longitudinal axis of the pipe and with this axis a first, predetermined Includes angle.

If the tube is set in rotation, the rotating device comprises a flat turntable which is inclined at an acute angle to the first axis, as well as means to put the tube on to fasten the axis of rotation in such a way that the longitudinal axis of the pipe intersects the first axis and with this axis the first, forms a predetermined angle.

In another preferred embodiment of a device According to the invention, a tool is provided for forming a flange, as well as means for this tool on the trimmed End of the pipe to set, and further means to the pipe and the flange tool relative to each other in such a way twist so that there is an outwardly protruding flange at the trimmed pipe end, which lies in the first plane. In this case, too, it is possible to rotate either the pipe or the tool forming the flange about the first axis offset.

The following description of preferred embodiments of the Finding is used in conjunction with the accompanying drawing further explanation. Show it:

Fig. 1 is a side sectional view of a pipe cutting

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Device according to the invention;

FIG. 2 is a front view of the device from FIG. 1, partially cut;

Figure 3 is a trimmed, flanged tube;

4 shows the connection of two pipes trimmed according to the invention to one another;

5 shows the production of a pipe bend from pipe sections according to the invention and

6 shows a schematic view of a modified embodiment a pipe cutting device according to the invention.

As can be seen from FIGS. 1 and 2, a device according to the invention comprises a housing 10, a spindle housing 12 and a Electric motor 14 with an adjustable gear for setting different speeds. Parts 12 and 14 are arranged in the housing 10. Furthermore, a turntable 16 is provided, a stand 18 and an arm 20 which protrudes from the stand 18 and is slidably attached thereto.

The spindle housing 12 contains a hollow spindle 22 which is connected to a wheel 2 4, which in turn has another Wheel 26 is driven by motor 14 by means of a belt 28. The upper end of the spindle 22 protrudes through the upper wall of the housing 10 and is non-rotatably connected to the turntable 16 outside this wall. A rod 30 inside

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the hollow spindle 22 is conical at its upper end with a beveled disc 32 and connected to a pedal 34 at its lower end.

The turntable 16 has a flat surface 36 that is at an angle of about 7.5 to the axis of the spindle 22 is inclined. An expandable clamping ring 38 is on the Surface 36 attaches and surrounds rod 30.

Two further, bow-shaped arms 40, 42 are pivotably mounted on the arm 20. The distance between these arms can be adjusted by a Screw 44 can be adjusted. The arm 40 carries a cutting roller 46 as well as one used to form a flange, another roller 48, while only one roller 50 is mounted on the arm 42, which serves as a shearing and forming roller. Because of the pivotable attachment of the arms 40, 42, the rollers have a certain degree of freedom so that they are in a limited Can move dimensions parallel to the arm 20. However, the arms 40, 42 are not appreciably movable in the direction of the arm 20.

The arrangement of the surface 36 of the turntable 16 relative to The axis of rotation of the disk, which coincides with the vertical axis of the spindle 22, is made such that the longitudinal axis 54 of a tube 52 pushed over the clamping ring 38 intersects the axis of rotation 56 of the turntable. The angle between the Axes 54 and 56 is approximately 7.5 °.

The tube 52 is held in place on the turntable by depressing the pedal 34. This will make the Rod 30 downwards and the beveled disc 32 into the clamping ring 3 8, so that it is expanded outwards and in frictional engagement with the inside of tube 52

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got. Thus, when the motor 40 is rotated, both the turntable and that held on it will rotate Pipe.

The arm 20 is lowered so that the various rollers 46, 48 and 50 are in their respective cutting or flange-forming positions reach. When the screw 44 is tightened, the rollers 46 and 50 cut through the pipe wall. Virtually at the same time, rollers 48 and 50 form an outwardly extending L-shaped flange at the trimmed end of the pipe. During the rotation of the pipe describes the point at which the cutting and flanging take place an elliptical path. The rollers 46, 48 and can move freely because of their pivotable mounting on the arm 20 adapt to the eccentric movement. Since the cutting point is fixed relative to the device and only the position of the Rotary disk is changeable relative to the device, cut the pipe and at the same time cut the flange along a Formed plane which is perpendicular to the axis of rotation 56 and with respect to the longitudinal axis of the tube at an angle of 7.5 ° is inclined.

Once the flange is formed, the pedal is released so that the tube separates from the clamping ring. The pipe can then removed from the device. Fig. 3 shows a perspective view of the flanged, trimmed Tube after removal from the device according to the invention. Fig. Shows a possibility for the mutual connection of two with Using the device described, trimmed and flanged pipes. A lower tube 60 has a L-shaped flange 62 on its upper edge, while an upper tube 64 has a simple flange 66 on its lower edge owns. The flanges 66 and 62 are engaged with each other

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brought. Then the upwardly protruding part of the flange 62 is knocked over the top of the flange 66, whereby the tubes are fastened to one another. In this way, several pipe sections can be connected to one another, for example in such a way that the pipe curvature shown in FIG. 5 arises over 90 °. The pipe bend shown in Fig. 5 consists of seven pipe sections 68, 70, 72, 74, 76 _{; /} and 80. The end faces of the segments 68 and 80 are perpendicular to the longitudinal axes of the pipe sections. However, their inner edges are trimmed at an angle of 7.5 °. In all sections 70 to 7 8 the ends are trimmed at angles of 7.5 °. If the pipe sections are put together accordingly, the result is a pipe curvature of 90 ° in total.

6 shows schematically an alternative to the embodiment 1 and 2. In FIGS. 1 and 2, the pipe is set in rotation while the cutting tool and that forming the flange Tool can be held stationary. In the embodiment of FIG. 6, the tube is held stationary while the cutting and flange forming rollers are rotated around the pipe. As in FIGS. 1 and 2, the tube 82 again held on an inclined plane 84 by means of an expandable clamping ring 86. An arm 88 that carries an electric motor 90 protrudes over the pipe. A radially protruding arm 92 is attached to the shaft 94 of the motor 90. At the end of the arm 92 the rollers for trimming the pipe and forming the flange are provided. The cutting process runs exactly as described above, with the only difference that the rollers are rotated around the pipe around the Cut off and cause the formation of the flange.

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Claims (21)

DR.-ING. DIPL.-INS. M SH, DIPL ₁ -PhYa. Drt. DIPL.-PHYS. HÖGER - STELLREC HT- GRIEBSBACH - HAECKER PATENT LAWYERS IN STUTTGART 28H438 A 42 808 m Registrant: _Pau i Werner Vormbaum ^m - ¹⁶⁸ 14-7th Street March 29, 197 8 _New Doornfontein Johannesburg Transvaal Republic of South Africa Patent claims: (1.) Method of trimming a pipe with a cutting tool, characterized by the following process steps: the cutting tool is in the cutting position placed on the pipe and the pipe and the cutting tool are rotated relative to each other in such a way that that the pipe is cut in a first plane which has a first acute angle with the longitudinal axis of the pipe includes. 2. The method according to claim 1, characterized in that the tube is rotated about a first axis which is the longitudinal axis of the pipe and forms a first predetermined angle with this axis. 3. The method according to claim 1, characterized in that the cutting tool is rotated about a first axis which intersects the longitudinal axis of the pipe and forms a first predetermined angle with this axis. 4. The method according to claim 2 or 3, characterized in that the first, predetermined angle is equal to the first acute Angle is chosen. 5. The method according to any one of claims 2 to 4, characterized in that that one attaches a tool forming a flange to the end of the pipe to be trimmed and the pipe and the tool forming the flange rotates relative to one another such that it is at the trimmed end of the tube forms an outwardly protruding flange, which in B0984 1/0957 ORIGINAL INSPECTED A 42 808 m,, _ _Λ March 29, 1978 is on the first level. 6. The method according to claim 5, characterized in that the tube is rotated about the first axis. 7. The method according to claim 5, characterized in that the the tool forming the flange is rotated about the first axis. 8. The method according to any one of claims 1 to 7, characterized in that that the first acute angle is chosen to be approximately 7.5 °. 9. The method according to any one of claims 1 to 8, characterized in that that the pipe is held on its inside by a chuck during the cutting process, which is expandable in frictional engagement with the tube. 10. The method according to any one of the preceding claims, characterized in that the tube is set in rotation about an axis is, wherein the longitudinal axis of the tube is inclined with respect to the axis of rotation at a predetermined angle and this axis of rotation intersects, and that a cutting tool is attached to the tube in such a way that when the tube rotates this is clipped along a plane perpendicular to the axis of rotation. 11. Device for performing the method according to one of the The preceding claims, characterized by a pipe cutting tool (46), means (40, 42) for Applying the cutting tool to the pipe (52) and a 809841/0957 A 42 808 m March 29, 197 8 Rotary device (16) for the pipe and the cutting tool to rotate relative to each other in such a way that the tube is cut through in a first plane, the one with the longitudinal axis of the tube encloses a first acute angle. 12. The device according to claim 11, characterized in that the rotating device (90, 92) around the cutting tool (46) a first axis rotated which intersects the longitudinal axis of the tube (52) and with this a first, predetermined Angle forms. 13. The apparatus according to claim 12, characterized in that the rotating device (90, 92) the cutting tool (46) in rotated in a plane perpendicular to the first axis. 14. The device according to claim 12, characterized in that the rotating device (16) the tube (52) about a first axis twisted, which intersects the longitudinal axis of the tube and forms a first, predetermined angle with this. 15. The apparatus according to claim 14, characterized in that the rotating device includes a flat turntable (16), which is inclined at an acute angle with respect to the first axis, and that means (38) are provided which the Hold the tube on the turntable in such a way that the longitudinal axis of the tube intersects the first axis and with this encloses the first predetermined angle. 16. The apparatus according to claim 15, characterized in that the fastening means comprise a clamping ring (38) which is attached to the turntable (16), and that the clamping ring is expandable in this way after being inserted into the tube (52) is that it is in frictional engagement with the inside of the pipe 809841/0957 -4- A 42 808 m March 29, 1978 * ^{U In} ^ " occurs. 17. Apparatus according to claim 15 or 16, characterized in that that a drive motor is used to drive the turntable (16) (12) is provided with variable speed. 18. Device according to one of claims 12 to 17, characterized characterized in that the cutting tool is prevented from moving in a direction parallel to the first axis is. 19. Device according to one of claims 12 to 18, characterized characterized in that a flange forming tool (48) is provided, further means (50) for this tool to apply in the flange position to the cut end of the tube (52) and means (16, 90 ·, 94) through which the tube and the tool forming the flange can be rotated relative to one another in such a way that a forms an outwardly directed flange on the trimmed end of the tube which lies in the first plane. 20. The device according to claim 19, characterized in that the rotating device (16) the tube (52) about a first axis twisted. 21. The device according to claim 19, characterized in that the rotating device (90, 92) is the tool forming the flange rotated around the first axis. 809841/0957 - 5 -