DE102013220622A1 - Cutting device and method for energy buffering and fixation for extruded plastic profiles - Google Patents

Abstract

The invention relates to a device for cutting a preferably thick-walled extruded tube (6), with at least one separating tool (7) and a receiving unit (8) for the separating tool (7) wherein the separating tool (7) is movable radially to the extrusion axis (9) and is rotatable about other means around the pipe to be cut (6) around to cut the pipe. According to the invention, it is provided that the receiving unit (8) comprises two racks (11, 12) arranged in a block (13), the first rack (11) being parallel and the second rack (12) being radially directed towards the extrusion axis (9) is movable and on the second rack (12) the separating tool (7) is arranged and the ring member (29) via an axial drive (17) is movable and by means of an adjusting unit (18) the penetration depth of the separating tool (7) and the travel determinable and the receiving unit (8) with a receiving disc (15) and a sleeve (14) is in communication, wherein on the sleeve (14) linear guide elements (22) are arranged parallel to the extrusion axis (9), wherein at least four linear guide elements (22) evenly distributed on the circumference of the sleeve (14). Furthermore, the invention relates to a clamping device for profiles and a method for cutting the profiles.

Description

The invention relates to a device for cutting a preferably thick-walled extruded tube, with at least one cutting tool and a receiving unit for the cutting tool, wherein the cutting tool is movable radially to the extrusion axis and rotatable about other means around the pipe to be cut off to cut the pipe.

For cutting extruded tubes usually so-called flying saws are used, with a circular saw blade either from below (underfloor saw), from above (dip saw) or from the side (cross saw) is brought to the pipe to be sawed, immersed in the cross section of the pipe and in the first step the wall thickness is severed. In the second step, the saw blade is passed around the pipe to completely cut the pipe. Here, the pipe to be cut is clamped during the sawing process; the saw carriage or saw carriage then moves synchronously with the continuous extrusion process with the extrusion speed ("flying saw").

If pipes are sawn, sawdust occurs. In addition, due to the friction of the saw blade on the pipe, in particular a plastic pipe, generates a static charge. This has the disadvantage that the sawdust stick to the pipe, which has a pollution result. The resulting waste often has to be declared as hazardous waste, which makes recycling impossible.

For small tubes, a device is already used, in which cutting to length without cutting takes place. Instead of a running saw, a round knife is passed around the pipe until the pipe wall is severed.

With the latter, non-cutting separation it is achieved to clean small pipe diameter with a thin cross-section clean, but it has not been possible to successfully cut off even thick-walled pipes with large to very large diameter - about 2m diameter. In these pipes, the saws described above were used again and again, which has the known disadvantages.

Experiments have shown that the main problem lies in guiding the knives exactly through the thick-walled pipe. Due to the large thickness and the large diameter of the knife is already misunderstood in the material at the slightest inclination, which has a breakage of the knife result.

The market requirement for such separation units is a high line speed with short cutting lengths and the ability to attach a chamfer, for example, in sewer pipes made of PP / PVC. Although there are known separation machines that can perform the separation process very quickly, but these usually have the disadvantage that they then can not chamfers or are not suitable for any plastic material. Separators, by means of which chamfering is possible, but usually have a relatively large sawing carriage and are therefore slow. The time required for a cut is very long.

In today's machines such as saws (flying saw) pipes of various diameters are cut through a Trennmesserarm or saw arm running around the pipe. All required functions such as arm forward / backward, clamp / release pipe and the corresponding position feedback messages are mounted on the rotating disk around the pipe. For this purpose slip rings are used for the electrical signals. The usual procedure is to use a separate slip ring track for each signal. Due to the size of smaller machines and the costs per slip ring, the signals and thus the available functions are limited.

One solution to the problems described above is in the DE 20 104 200 but does not yet provide satisfactory solutions.

The invention is therefore the object of the known expertise of a generic separator equipped with a knife to develop such that it is possible to accomplish a reproduced separation process, wherein the delivery of the knife takes place such that tilting is excluded and as few components are needed. Furthermore, the task is to offer a method to deal with the energy used energy and environmentally conscious. The same applies to the clamping of the profiles.

The solution of the objects is given in the claims.

This embodiment of the device ensures uniform rectilinear movement. The axial and radial movement of the separating device along the extrusion axis can thus be combined in one drive.

The drive of the racks takes place by means of a single axial drive. As a result, both installation space and material is saved, whereby the entire device can build smaller.

Advantageously, the racks are coupled in the block. In this way we achieved that the distance of the first rack corresponds to the distance of the second rack. The distances traveled by the number bars are absolutely synchronous. After appropriate adjustment of the racks, it is ensured that the penetration depth of the separating device into the outer wall of the plastic profile is substantially identical for all separating devices arranged on the circumference. Differences can only be accompanied by tolerances in the profile cross-section.

It is also proposed that the cutting tool is a cutting knife or a tool for chamfering the edges. Depending on the desired application, either the transection of the profile strand or the attachment of a bevel on the front side of the tube can be done. It is also conceivable to design a cutting tool so that both the cutting and the chamfering are included.

In a further development it is provided that the block with the racks are arranged on a receiving disk, wherein the first rack is in communication with a ring element, which is movable on a sleeve along the extrusion axis back and forth. The pickup disc is rotated about the extruded tube by means of a drive. Several units of the block with the racks can be arranged on the receiving disk, whereby the required rotation about the profile and / or the time required for cutting or chamfering is minimized.

Furthermore, we proposed that the cutting tool is operatively connected to a ring member and the ring member is bewergbar via an axial drive and by means of an adjustment the penetration depth of the cutting tool and the travel can be determined.

By means of this embodiment of the device, the travel distance and the penetration depth of the separating tool are realized via one and the same drive and thus at least two functions are implemented over a part of the device.

The axial drive is adjustable via pneumatic cylinders. The drives over which several functions are realized is thus a pneumatic drive according to the invention.

The adjustment has limit switches by means of which the switching of the direction of movement is initiated. The position of the limit switches during manual adjustment can be determined via a scale.

The adjustment of the limit switch can also be done via an electric linear drive. Advantageously, this is controlled via the machine control of the extrusion line. Likewise, the pneumatic cylinder of the axial drive can be an electric drive, for example a servomotor.

Advantageously, the ring element consists of an inner ring and an outer ring, wherein the outer ring is coupled via a connecting part with the axial drive. Thus, the ring member can be axially displaced without it being completely rotated, as between the inner ring and the outer ring of the ring member axial forces are transferable. The axial movement is transferred from the axial drive to the inner ring via the outer ring and passed on to the first pay bar. By coupling the first rack to the second rack via the block, an axial movement into a radial movement of the separating device can be realized via a drive. The radial movement serves as a cutting movement for the separating device

Advantageously, the ring element is designed as a thrust bearing.

The receiving unit is connected to a receiving disk and a ring element, wherein on the ring element linear guide elements are arranged parallel to the extrusion axis, wherein at least four linear guide elements are distributed uniformly on the circumference of the ring member.

Such linear guide element unnecessary a hardened and smooth surface of the ring member, it is sufficient for the exact positioning of the linear guides on the circumference of the ring member.

According to training, the receiving disk is axially guided over the linear guide elements and thus moved equidistantly around the extrusion axis. It is provided that the linear guide elements are commercially available linear guide profiles.

On the receiving unit is arranged on a receiving disk, wherein the receiving disk along the extrusion axis is moved back and forth, wherein the receiving disk rotates about the extrusion axis, wherein for the movement of the receiving disk, a three-phase motor is arranged, wherein for moving the receiving disk energy is provided and Braking the pick-up disk energy is generated, wherein the energy generated is buffered and delivered to consumers connected in the system.

By this method, the flywheel of the receiving disk is used to absorb stored potential energy during braking and to make it available to other consumers.

According to training, it is provided that the energy thus obtained / generated is used to accelerate the pickup disk, whereby the effectiveness is increased, since the starting current can be designed smaller.

As a further possible use, it is proposed that the energy generated be used to move the separator.

With the method according to the invention, the kinetic energy is recovered and used beneficially. The proposed method can be seen analogously to the KERS system used in Formula 1, again, the kinetic energy is buffered and retrieved as needed.

For fixing the profile, it is proposed that a clamping element is arranged in each of the clamping devices and the clamping elements are movable via a drive radially to the extrusion axis, wherein each clamping device is connected to the adjacent clamping device via a coupling device.

This configuration ensures that all clamping devices arranged around the tube are simultaneously adjusted, whereby a centric position of the tube about the extrusion axis is ensured. Thus, it can not be any of the clamps before or after

Training is provided that two to eight clamping devices are arranged equidistant around the profile. With two clamping devices, the tube is already held firmly, with three clamping devices sufficiently centered. With more than three clamping devices, an even better positional fixation of the tube is achieved.

According to a further development, it is proposed that all clamping elements of all arranged clamping devices can be moved via the drive, whereby all clamping elements are adjusted synchronously, since none of the clamping devices can move forward or behind via the coupling.

Advantageously, the coupling device is a propeller shaft with gear arranged and the clamping elements are connected to a rack.

In the drawings, a device according to the invention is shown schematically:

1 shows a typical extrusion line

2 the part of the separator

3 the part of the separator in a different position

4 an enlarged view of the adjustment

5 the part of the clamping device

1 shows a typical extrusion line, as used today for profile extrusion, whether for the production of window profiles or pipes. It shows an extruder 1 , in which plastic is melted, and continuously for shaping in the extrusion tool 2 is encouraged. This is followed by a calibration and cooling station 3 Depending on the profile, additional cooling stations can be used. After the cooling stations, a trigger device closes 4 at. To the endless profiles 6 to cut to the desired length is then a separator 5 arranged.

2 shows a schematic representation of the separation device according to the invention and corresponds to the position 5 as shown in 1 , Around the extrusion axis 9 is a sleeve 14 with linear guides 22 arranged, which with a ring element 29 is in active connection. At the pick-up disc 15 are separating tools 7 arranged over racks 11 and 12 be adjusted.

The ring element 29 can along the extrusion axis 9 in or against the extrusion direction 10 be moved. To move the ring element 29 is an axial drive 17 intended.

The ring element 29 consists of an inner ring 30 and an outer ring 31 the over the connecting part 32 with the axial drive 17 is coupled. The drive is a pneumatic cylinder 19 its direction switching by means of limit switches 21 is realized. For determining the position of the limit switches 21 a manual adjustment uses a scale 20 ,

Depending on the position of the limit switch 21 become the dental forceps 11 and 12 more or less over the pneumatic cylinder 19 moves and thus the penetration depth of the separation tool 7 in the pipe to be cut 6 certainly. Furthermore, the rotary drive 16 for the pick-up disc 15 represented, which rotates the one or more cutting knife to the abzulängende pipe.

The real parting tool 7 is at a receiving unit 8th arranged, this can be screwed, clamped or otherwise attached. In the illustrated embodiment, a circular cutting blade is used. It could be too be a mold by means of which a chamfer can be attached. The recording unit 8th is in turn on a second rack 12 arranged over a block 13 with a first rack 11 is in active connection. The block 13 is on a pickup disk 15 arranged, via the rotary drive 16 around the extrusion axis 9 is rotatable.

By means of this axial drive 17 we are moving the two racks 11 . 12 over the block 13 implemented, so that only one drive is required for the axial and radial movement of the cutting blade. About the coupling in the block 13 we converted the axial into a radial movement, the radial movement serves as a cutting movement for the separating device.

At the pick-up disc 15 can be several of the blocks 13 be arranged with the number bars, for example, only two are shown here, these are arranged so that an imaginary straight connecting line of the two centers of the cutting tool 7 the extrusion axis 9 radial cuts.

Furthermore, a ring element 29 arranged that with the first racks 11 is in operative connection and along the linear guides 22 on the sleeve 14 is movable back and forth. The ring element 29 is equidistant to the sleeve 14 and is about the axial drive 17 along the extrusion axis 9 postponed. The pipe / profile, not shown 6 we in the extrusion direction 10 emotional.

3 corresponds essentially to the illustration according to 2 , The difference is that the ring element 29 is shown in a different position. About the axial drive 17 became the ring element 29 moved axially. The outer ring 30 of the ring element 29 is over the connecting part 32 with the axial drive 17 coupled. The outer ring 30 transfers the axial forces to the inner ring 31 and moves the ring element 29 along the linear guides 22 and in the extrusion direction 10 , The inner ring 31 of the ring element 29 stands with the first rack 11 the separator in connection. By coupling the racks over the block 13 becomes the second rack at the same time 12 moved in the radial direction. There on the rack 12 the cutting knife over the receiving unit 8th is arranged, the lengthening of the pipe, not shown, is made.

Around the extrusion axis 9 is a sleeve 14 with linear guides 22 arranged, which with a ring element 29 is in active connection. At the pick-up disc 15 are separating tools 7 arranged over racks 11 and 12 be adjusted.

The ring element 29 becomes so along the extrusion thing 9 over on the sleeve 14 assembled linear guide elements 22 moved axially.

The ring element 29 can along the extrusion axis 9 in or against the extrusion direction 10 be moved. To move the ring element 29 is an axial drive 18 provided also with the ring element 19 is in active connection. The drive is a pneumatic cylinder 19 its direction switching by means of limit switches 21 is realized. For determining the position of the limit switches 21 a manual adjustment uses a scale 20 ,

Furthermore, the rotary drive 16 for the pick-up disc 15 shown.

The 4 shows in an enlarged view the part of the adjustment 18 out 2 , wherein like parts are marked with like reference numerals.

5 shows a schematic representation of the clamping device according to the invention. It is preferably in the region of the separating device 5 be used, so that the profile to be cut 6 is fixed during separation process itself. However, it is also conceivable to use the proposed clamping device at a different location of the extrusion line, where fixation of the profile is required. Particularly useful is the device for fixing pipes, since the profile cross-section is circular.

Around the extrusion axis 9 along the extrusion direction 10 is part of the profile 6 shown. The profile 6 is fixed in position via clamping devices. For this purpose, several of the clamping devices on the circumference of the profile 6 arranged distributed. All arranged clamping devices are via coupling devices 28 connected to each other, wherein the coupling device 28 in each case a first clamping device 23 with an adjacent second clamping device 24 combines.

Each of the arranged clamping devices has a clamping element 25 its contact surface 27 on the outer surface of the profile 6 can be applied. Each of the clamping devices has a servomotor, which is advantageously a servomotor, about the clamping element radially to the extrusion axis 9 to move. One of the clamping devices is with a drive 26 equipped to take over the main control of the clamping devices. Similar to a server / client solution, the other clamping devices, via the coupling device 28 connected after the drive 26 , This design ensures that all around the pipe 6 arranged clamping devices are adjusted synchronously, creating a centric position of the pipe 6 around the extrusion axis 9 is guaranteed.

LIST OF REFERENCE NUMBERS

1

 extruder

18

 adjustment

2

 extrusion die

19

 pneumatic cylinder

3

 Calibration and cooling tank

20

 scale

4

 off device

21

 limit switch

5

 separating device

22

 linear guide

6

 profile

23

 first clamping device

7

 parting tool

24

 second clamping device

8th

Recording unit for 7

25

 clamping element

9

 extrusion axis

26

Drive for 23 and 24

10

 extrusion direction

27

Bearing surface of 25

11

 first rack (parallel)

28

Coupling device between 23 and 24

12

 second rack (radial)

29

 ring element

13

 block

30

Outer ring of 29

14

 shell

31

Inner ring of 29

15

 receiving disc

32

 connecting part

16

Rotary drive for 15

17

Axial drive for 29

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 20104200 [0009]

Claims (8)

Device for cutting a preferably thick-walled extruded tube ( 6 ), with at least one separating tool ( 7 ) and a recording unit ( 8th ) for the cutting tool ( 7 ) wherein the separating tool ( 7 ) radially to the extrusion axis ( 9 ) and by further means around the pipe to be cut ( 6 ) is rotatable around to cut the tube, characterized in that the receiving unit ( 8th ) two in one block ( 13 ) arranged racks ( 11 . 12 ), wherein the first rack ( 11 ) parallel and the second rack ( 12 ) radially to the extrusion axis ( 9 ) is movable back and forth and on the second rack ( 12 ) the separating tool ( 7 ) and the separating tool ( 7 ) with a ring element ( 29 ) is in operative connection and the ring element ( 29 ) via an axial drive ( 17 ) is movable and by means of an adjustment ( 18 ) the penetration depth of the separating tool ( 7 ) and the travel path can be determined and the receiving unit ( 8th ) with a receiving disk ( 15 ) and a sleeve ( 14 ), wherein on the sleeve ( 14 ) Linear guide elements ( 22 ) parallel to the extrusion axis ( 9 ) are arranged, wherein at least four linear guide elements ( 22 ) evenly on the circumference of the sleeve ( 14 ) are distributed. Apparatus according to claim 1, characterized in that the drive of the racks ( 11 . 12 ) by means of a single axial drive ( 17 ) and in block ( 13 ), wherein the path of the first rack ( 11 ) the distance of the second rack ( 12 ) or the axial drive ( 17 ) via pneumatic cylinders ( 19 ) is adjustable and the adjusting unit ( 18 ) a scale ( 20 ) or via the linear guide elements ( 22 ) the ring element ( 15 ) is axially feasible and the linear guide elements ( 22 ) are commercially available linear guide profiles. Device according to claim 2, characterized in that the block ( 13 ) with the racks ( 11 . 12 ) on a receiving disc ( 15 ) are arranged, wherein the first rack ( 11 ) with a ring element ( 29 ) connected to a sleeve ( 14 ) along the extrusion axis ( 9 ) is movable to and fro or limit switch ( 21 ) initiate the switching of the direction of movement and the limit switches ( 21 ) are manually adjustable or the adjustment ( 18 ) and the axial drive ( 17 ) is adjustable via an electric linear drive. Device for profile extrusion consisting of at least two clamping devices ( 23 . 24 ) equidistant around the circumference of a profile to be extruded ( 6 ) are arranged, wherein a clamping element ( 25 ) directly on the profile to be extruded ( 6 ) can be applied, characterized in that the clamping element ( 25 ) in each of the clamping devices ( 23 . 24 ) is arranged and the clamping elements ( 25 ) via a drive ( 26 ) radially to the extrusion axis ( 9 ) are movable, each clamping device ( 23 ) with the adjacent clamping device ( 24 ) via a coupling device ( 28 ) connected is. Apparatus according to claim 4, characterized in that two to eight clamping devices ( 23 . 24 ) equidistant around the profile ( 6 ) are arranged and via the drive ( 26 ) all clamping elements ( 25 ) of all arranged clamping devices are movable, wherein the coupling device ( 28 ) is a propeller shaft with arranged gear. Device according to one of claims 5 or 5, characterized in that the clamping elements ( 25 ) are connected to a rack. Method for cutting to length a preferably thick-walled extruded tube ( 6 ), with at least one separating tool ( 7 ) and a recording unit ( 8th ) for the cutting tool ( 7 ) wherein the separating tool ( 7 ) radially to the extrusion axis ( 9 ) and by further means around the pipe to be cut ( 6 ) is rotated around to cut the tube, characterized in that the receiving unit ( 8th ) on a receiving disc ( 15 ), wherein the receiving disc ( 15 ) along the extrusion axis ( 9 ) is moved back and forth, wherein the receiving disc ( 15 ) around the extrusion axis ( 9 ) is rotated, whereby for the rotation of the receiving disc ( 15 ) a three-phase motor ( 16 ) is arranged, wherein for moving the receiving disc ( 15 ) Energy is provided and when braking the recording disc ( 15 ) Energy is generated, whereby the generated energy is buffered and delivered to consumers connected in the system. A method according to claim 7, characterized in that the energy generated for accelerating the receiving disk ( 15 ), wherein the energy generated for the process of the separation device ( 5 ) is used.

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