KR100929738B1 - Device for cutting a rotationally symmetrical body - Google Patents

Abstract

The invention relates to an apparatus for cutting a body (30) which is rotationally symmetric in a plane perpendicular to the longitudinal axis (M) of the body (30).

a) the table 10 comprises two or more supports 18, 20 arranged on the table 10, the supports being positioned spaced apart from each other in the axial direction of the body 30, and positioned in the table 10. It is provided to accommodate the body 30,

b) each support 18, 20 comprises two or more rotatable rollers 22, 24 spaced apart from one another such that the shaft is offset with respect to the axial direction of the body 30 by 3 ° and extends parallel to each other. and,

c) Counter support 32 is provided with a central ball bearing from which three or more arms 36, 38, 40 radially spread in various directions along the plane,

d) While the body 30 is rotating, the counter support 32 is arranged such that the arms 36, 38, 40 are adjacent to the free end face 30s of the body 30, positioned above the table 10. , And

e) The cutting device 42 is characterized in that it is movable relative to the body 30 located perpendicular to the longitudinal axis.

Description

DEVICE FOR CUTTING A ROTATIONALLY SYMMETRICAL BODY}

The present invention relates to an apparatus for cutting a rotationally symmetrical body. The body which is rotationally symmetrical can be, for example, a pipe or a drain for conveying a beverage or wastewater. Rotationally symmetrical bodies are constructed of solid material or have a cylindrical or tubular form.

Such tubular bodies can be made of plastic, for example by the so-called rotational molding method. Such a rotary molding method is disclosed in detail in EP 0 360 758 A2.

In this way, the wall of the pipe is formed inside the rotary mold. When the pipe is removed from the mold, the pipe has a constant inner and outer diameter. However, the free end face of the pipe includes certain irregularities caused by the manufacturing process. That is, the two end faces of the tubular body do not always extend inside the face lying perpendicular to the pipe axis. In the shape of the pipe end face, some irregularities can be accommodated in certain applications. However, the exact planar end face of the tubular body is required in other fields. This is the so-called "improved pipe". In this case, the pipe is installed directly on the ground without prior digging. Pipes pressurize the ground in a hydraulic manner. For example, the pipe is required to be installed in this way for a distance of several hundred meters. The pipeline thus consists of several pipe portions which adjoin each other to the end faces of the pipeline and which are continuously pressed to the ground. If the end face of the improved pipe is not formed with the correct face and is not aligned exactly perpendicular to the pipe axis, stress concentration is inevitably generated, whereby the stress concentration is a pipe-pushing process. Disruptive effects are induced during the formation and are large enough to exceed locally acceptable stress limits.

It is known to cut the end of a pipe with a circular saw to produce a pipe end face of the correct face. For this purpose, the pipe is positioned on the table, and at least two supports for receiving the body positioned on the table are arranged to be spaced apart from each other in the axial direction of the body. Each support consisting of at least two rotatable rollers is positioned spaced apart from one another so that the pipe to be cut can be received between the respective rollers.

The pipe is cut by the saw mentioned above while rotating over the table, for example to cut into small end portions. However, during this operation, an axial displacement of the pipe on the table occurs. Due to this axial displacement, the cutting surface is not positioned to form exactly perpendicular to the pipe axis, but extends helically. For example, one reason for displacing the pipe in the axial direction is that the above mentioned roller of the pipe support does not extend to be exactly parallel to the axial direction of the pipe or the roller is repositioned in excess time while the cutting device is operating. .

In this respect, the observed deviation from the correct vertical cut (on the horizontally correctly supported pipe) is formed in centimeters and, consequently, is unacceptable.

1 shows an apparatus according to the invention comprising a pipe placed in the apparatus, an end part being cut off in a schematic representation.

* Symbol description *

10: table

18,20: support

22, 24: roller

30: body

30 s: end face

36, 38, 40: cancer

It is therefore an object of the present invention to provide an apparatus for cutting a rotationally symmetrical body, capable of accurate cutting in a plane located perpendicularly to the longitudinal axis of the rotationally symmetrical body.

In order to achieve this purpose, the following characteristics are followed.

In certain applications, it is practically impossible to ensure accurate alignment of the support rollers beyond the extension time. Even if such precise alignment is ensured, it is impossible to prevent axial displacement of the body (eg pipe) which is rotationally symmetrical caused by the force generated on the table during the cutting operation.

In conclusion, a first feature of the invention lies in generating specific and positive axial displacements of the body by aligning the rollers of the support at a particular angle.

It is a second feature of the present invention to simultaneously counteract this undesirable axial displacement of the body.

In this aspect, during the cutting operation, the body rotates to produce an irregular cutting surface, thus only providing static counter support for the end faces of the rotationally symmetrical body to be cut. Is not enough.

In conclusion, the third aspect of the present invention is to design a counter support which is freely movable in all three directions of the coordinate system. Of course, the counter support is generally required to have a stable position.

A general embodiment of the present invention includes the following features and relates to an apparatus for cutting a body that is rotationally symmetrical in a plane perpendicular to the longitudinal axis of the body.

a) the table comprises two or more supports arranged on the table, the supports being positioned spaced apart from each other in the axial direction of the body and provided to receive a body positioned with the table,

b) each support comprises two or more rotatable rollers spaced apart from each other such that the shaft is offset with respect to the axial direction of the body by 3 ° and extends parallel to each other,

c) the counter support is provided with a central ball bearing, from which three or more arms spread radially in various directions along the plane,

d) while the body is rotating, the counter support is arranged such that the arm is adjacent to the free end face of the body located above the table, and

e) The cutting device can be moved relative to the body 30 located perpendicular to the longitudinal axis.

The angle of the roller is sufficient to be formed, for example, less than 1 ° or 2 °, 3 °.

Due to the specific minimum angle of the roller (relative to the axial direction of the tubular body and the longitudinal direction of the table), the turning body is axially oriented in the direction of the counter support (counter bearing) above the support so that a certain pressure is applied to the counter support. Is moved to.

The counter bearing has a fixed position, and the central ball bearing allows the counter bearing to operate substantially in a cardanic fashion. In such a case, the above-mentioned arms, which radiate radially from the ball bearings, are adjusted to match the shape of the end face formed in the body, ie the arm is in contact with the still irregular end face of the body.

In addition to the stationary mounting of the arm on the ball bearing, the shape of the counter bearing provided with the ball bearing allows the axial position of the rotationally symmetrical body to be fixed and rotated simultaneously (while cutting operation). .

Corresponding cutting devices, for example circular saws, can be aligned with respect to the pipe (rotating symmetrical body) such that the saw blade extends exactly perpendicular to the longitudinal central axis of the body, the cutting surface being about the entire circumference of the tubular body. It is made to extend in a plane located perpendicular to the longitudinal central axis of the pipe.

The cutting device can be for example a high pressure water jet cutter or a laser cutter.

In one embodiment, it is proposed to arrange the counter support to axially adjust the rotationally symmetrical body. However, the counter supports are each fixed in a controlled position. The counter support can be arranged such that the height can be adjusted. This is practically required, especially when bodies of various diameters need to be cut in the same system (apparatus). The position of the ball bearings is in each case fixed at an adjustable height.

In another embodiment, the method includes cutting a body having various diameters, and the length of the counter bearing arm can be variously formed. This can be accomplished by attaching the extension to the arm present. However, cancer can be achieved in a telescopic manner. In any case, the arm is required to have a length such that the arm can contact the end face of the pipe.

One side faces the body which is rotationally symmetrical, and the arms can be achieved such that the arms are all located in one plane. However, this is not necessary because the counter support is provided with a ball bearing. In general, the counter support may preferably comprise only two arms extending in opposite directions. There can be provided a planar end support, for example a circular disk, in which the pressure surface of the planar end support (contact surface to the end face of the body) can be reversibly deformed within certain limits, thereby providing a pressure surface Can be applied to irregular end faces of the body. In the context of the present invention, the present invention may conform to an embodiment having “innumerable cancers”. However, while the body rotates on the table without causing axial displacement of the body, it is required that a central ball bearing be provided to mitigate the desired wobbling movement.

The arm may be provided with a friction lining to improve static friction between the corresponding end face of the rotationally symmetrical body and the arm of the counter support. Such friction linings may be provided on the rollers of the support.

The radial arrangement of the counter support arms can be achieved by the arms forming an angle at 120 ° to each other, like a star. This example is described below.

The inclined position of the support roller can be chosen such that the roller offsets from the free end of the roller by 5 mm (particularly 0.5 to 1.5 mm) with respect to the axial direction of the tubular body. However, it is always required to ensure that the axes of the support rollers extend parallel to each other.

Other features of the invention are disclosed in the dependent claims as well as other applications.

One embodiment of the present invention is described in more detail below.

Reference numeral 10 denotes a table comprising two parallel beams 12, 14 connected to each other by a crossbeam 16. The two supports 18, 20 are spaced apart from each other and are arranged between the beams 10 (referred to in the longitudinal direction of the beam 10). Each support 16, 18 has two rollers ( 22, 24, the axes 26 of the two rollers being offset by 0.5 ° with respect to the longitudinal center axis M of the pipe 30 positioned with the table 10, respectively. The two rollers 22, 24 of each support 18, 20 are positioned spaced apart from each other so that the pipe 30 can be received between the two rollers (with respect to the longitudinal direction of the beams 12, 24). Referred to in a vertically extending direction).

The counter support 32 is arranged at one end of the table 10 and the mounting of the counter support is not shown in the figure for a better illustration. The counter support 32 includes an annular body 34 arranged in the center, and ball bearings are arranged in the annular body. The three arms 36, 38, 40 extend radially outward from the annular body 34, and the arms 36, 38; 38, 40; 40, 36 are each 120 ° from each other. Is formed. The surface of the arms 36, 38, 40 is formed towards the corresponding end face 30s of the pipe 38 lying in one plane.

Due to the ball bearing, the counter support 32 can be moved in all three directions of the coordinate system independently of the shape of the end face 30s formed in the pipe 30. After operating the supports 18, 20, the pipe 30 moves towards the arms 36, 38, 40 in the axial direction M until it comes into contact with the arms. The pipe 30 cannot be moved further in the axial direction on the table 10 after reaching the position.

A saw 30 mounted to a swivel arm 44 and arranged at the other end of the pipe 30a may be guided vertically towards the surface of the pipe 30. Due to the correct axial positioning of the pipe 30, the cutting surface on the rotating pipe 30 can be provided to extend exactly perpendicular to the longitudinal axis M of the pipe 30.

In the figure shown, the pipe 30 is cut into end portions having a length L. In FIG.

Due to the suction tube 46 mounted to the beam 12, foreign matter accumulated during the cutting operation can be immediately removed.

The end face 30s of the pipe 30 is in contact with the arms 36, 38, 40 during the entire cutting operation, which arm is rotated relative to the ball bearing to coincide with the rotation of the pipe 30.

 In order to adjust the roller to the correct position, one embodiment proposes to align the roller shaft with the aid of the adjusting screw.

Claims (8)

In the device for cutting the body 30 which is rotationally symmetric in a plane perpendicular to the longitudinal axis M of the body 30, the device a) the table 10 comprises two or more supports 18, 20 arranged on the table 10, the supports being positioned spaced apart from each other in the axial direction of the body 30, and positioned in the table 10. It is provided to accommodate the body 30, b) each support 18, 20 comprises two or more rotatable rollers 22, 24 spaced apart from one another such that the shaft is offset with respect to the axial direction of the body 30 by 3 ° and extends parallel to each other. and, c) Counter support 32 is provided with a central ball bearing from which three or more arms 36, 38, 40 radially spread in various directions along the plane, d) While the body 30 is rotating, the counter support 32 is arranged such that the arms 36, 38, 40 are adjacent to the free end face 30s of the body 30, positioned above the table 10. , e) The cutting device 42 is characterized in that it is movable with respect to the body 30 positioned perpendicular to the longitudinal axis. 2. Device according to claim 1, characterized in that the counter support (32) is adjustable in the axial direction of the body (30). 2. Device according to claim 1, characterized in that the height of the counter support (32) is adjustable. 2. Device according to claim 1, characterized in that the length of the arms (36, 38, 40) formed on the counter support (32) is telescopically variable. 2. Device according to claim 1, characterized in that the counter support (32) comprises three arms (36, 38, 40) which form an angle with respect to each other at 120 degrees. 2. Device according to claim 1, characterized in that the arm (36, 38, 40) of the counter support (32) is provided with a friction lining on the side of the arm facing the body (30). 2. Device according to claim 1, characterized in that the rollers (22, 24) of the support (18, 20) are offset at or below 5 mm with respect to the axial direction of the body (30) at the free end of the roller. 2. Device according to claim 1, characterized in that the position of the rollers (22, 24) formed on the support (18, 20) is adjustable by screws.