EP0097992B1 - Method and apparatus for contour cutting of plastic products - Google Patents

Method and apparatus for contour cutting of plastic products Download PDF

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Publication number
EP0097992B1
EP0097992B1 EP83200884A EP83200884A EP0097992B1 EP 0097992 B1 EP0097992 B1 EP 0097992B1 EP 83200884 A EP83200884 A EP 83200884A EP 83200884 A EP83200884 A EP 83200884A EP 0097992 B1 EP0097992 B1 EP 0097992B1
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EP
European Patent Office
Prior art keywords
filaments
movement
starting material
framework
block
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Expired
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EP83200884A
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German (de)
French (fr)
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EP0097992A1 (en
Inventor
Hendricus Johannes Maria Van Dijk
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Gebr Van Dijk Bv
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Gebr Van Dijk Bv
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B26HAND CUTTING TOOLS; CUTTING; SEVERING
    • B26FPERFORATING; PUNCHING; CUTTING-OUT; STAMPING-OUT; SEVERING BY MEANS OTHER THAN CUTTING
    • B26F3/00Severing by means other than cutting; Apparatus therefor
    • B26F3/06Severing by using heat
    • B26F3/08Severing by using heat with heated members
    • B26F3/12Severing by using heat with heated members with heated wires
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B26HAND CUTTING TOOLS; CUTTING; SEVERING
    • B26DCUTTING; DETAILS COMMON TO MACHINES FOR PERFORATING, PUNCHING, CUTTING-OUT, STAMPING-OUT OR SEVERING
    • B26D1/00Cutting through work characterised by the nature or movement of the cutting member or particular materials not otherwise provided for; Apparatus or machines therefor; Cutting members therefor
    • B26D1/01Cutting through work characterised by the nature or movement of the cutting member or particular materials not otherwise provided for; Apparatus or machines therefor; Cutting members therefor involving a cutting member which does not travel with the work
    • B26D1/547Cutting through work characterised by the nature or movement of the cutting member or particular materials not otherwise provided for; Apparatus or machines therefor; Cutting members therefor involving a cutting member which does not travel with the work having a wire-like cutting member
    • B26D1/553Cutting through work characterised by the nature or movement of the cutting member or particular materials not otherwise provided for; Apparatus or machines therefor; Cutting members therefor involving a cutting member which does not travel with the work having a wire-like cutting member with a plurality of wire-like cutting members

Definitions

  • the invention relates to a method for simultaneously contour cutting a plurality of identical uniform plastic products from a single block of starting material, using a plurality of filaments disposed in parallel array for engagement of said single block and heated by an electric current, the filaments being given an oscillating movement along their longitudinal axis, the starting material being given a movement in the horizontal direction and at least some of the filaments being given a synchronised alternating movement in the vertical direction.
  • the invention also relates to an apparatus for simultaneously contour cutting a plurality of identical uniform plastic products from a single block of starting material, according to the above method, comprising a work table movable substantially in a horizontal direction for receiving at least a part of a block of starting material, a drive mechanism for horizontal movement of the work table, a number of substantially vertical columns, a framework supporting a plurality of electrically heated filaments in parallel array as cutters for said block of starting material, a drive for imparting an oscillating movement to the filaments along their longitudinal axis, and drive means for imparting alternating vertical movement synchronised with the horizontal movement to at least some of the filaments.
  • Such a method and apparatus are known from US ⁇ A ⁇ 3 786 701 in which a method and apparatus are disclosed for simultaneously contour cutting a plurality of identical uniform plastic products from a single block of starting material, using a plurality of filaments disposed in parallel array and heated by an electric current, the filaments being given an oscillating movement along their longitudinal axis and the starting material being given a movement in the horizontal direction, and at least some of the filaments being given a synchronised alternating movement in the vertical direction.
  • This known method and apparatus are only intended for cutting during motion of the supporting platform in one single direction, and the framework in which two sets of parallel cutting filaments are mounted is given an oscillating movement as a whole.
  • One set of parallel cutting filaments is directly connected to the frame by means of longitudinally aligned springs, while a second set of parallel cutting filaments is connected to movable bars by means of springs in which the movable bars move vertically in the plane of mounting of the filaments and are directly controlled by guide wheels, following patterns which are fixedly connected to the apparatus.
  • the array of filaments is maintained in a common horizontal plane during cutting whereby said array has imparted to it an alternating programmed movement in the vertical direction, and a correspondingly programmed alternating movement is imparted to the block of starting material in the horizontal direction, thus defining in combination a prescribed cutting contour of each filament relative to the block of starting material.
  • an apparatus of the type indicated above is characterized in that the framework is U-shaped and is disposed substantially in a horizontal plane such that the array of filaments is supported in a common horizontal plane, the drive for longitudinal oscillation of the filaments being adapted to oscillate the filaments within said U-shaped frame, in that the driving means for alternating vertical movement of the array of filaments are adapted to move the U-shaped framework up and down along the vertical columns according to a program thus transporting the plane of the filament array vertically, and in that the drive mechanism for horizontal movement of the work table is provided with a program for the horizontal alternating displacement of the work table, such that in combination with the programmed movement of the framework, the filaments follow a prescribed cutting contour relative to the block of starting material.
  • a method for contour cutting a plurality of uniform plastic products from a block of starting material using a plurality of filaments disposed in parallel array and heated by an electric current, in which the block of starting material is given a programmed alternating movement, that is substantially parallel to the plane of the filaments.
  • the filaments are only given a vertical movement, which is not alternating when the method is carried out, and the corresponding programmed movement in the horizontal direction of the block of starting material is obtained by means of a cammed wheel, by which it is only possible to obtain a quite simple form of contour.
  • EP-A-0 035 852 an apparatus for contour cutting is described using four vertical columns disposed around the work table to support and guide a U-shaped framework, each column being provided with drive means for the vertical displacement of that part of the framework supported by the column.
  • this known apparatus use is made of an endless cutting wire rotating on discs, and the framework, in which the cutting wire has been mounted, is given a movement in one direction, and the product to be cut a movement at right angles to the first movement. It is possible, by using this apparatus, to cut at most two blocks of material into a shape having a desired contour.
  • this apparatus for cutting two identical products at the same time is already quite complicated, and it cannot be seen how an increased number of products could easily be cut at the same time.
  • the apparatus depicted in Figure 1 comprises a base frame 1 on which four vertical columns 2 have been mounted in a rectangle. Enclosed within the columns is a work table 3. In the long direction of the apparatus a supporting beam 4 has been provided at both ends. These supporting beams are suspended on vertical carrier heads 5 which can be moved along the columns 2. Each of the carrier heads 5 is connected through a chain 6 and a sheave 7 with a counterweight 8. The load of this counterweight 8 is chosen such that it virtually compensates the load of the framework with supporting beams and any other components fitted to it weighing on each carrier head 5. Each of the carrier heads 5 can be displaced in a vertical direction by driving means - not shown in the drawings - moving synchronously for each carrier head, such as a screw spindle with nut. All these driving means are linked together for the four columns by means of drive shafts 9 and 10 in the longitudinal and crosswise direction, respectively.
  • a drive motor is denoted by 11. Obviously, more drive motors may be applied, provided a vertically uniform displacement of the carrier heads is ensured.
  • the columns are connected together at the top by means of structural shapes 12 and 13, respectively.
  • Each of the supporting beams 4 is provided at the location of a vertical column 2 facing the carrier head with a coupling flange 14 for the attachment of the U-shaped framework to be discussed below.
  • a screw spindle 15 with driving motor 16 has been mounted underneath the work table 3. This screw spindle meshes with a nut incorporated into a support 17 underneath the work table 3.
  • the motor 16 enables the work table 3 to be moved to and fro over a distance of about two metres.
  • the left-hand portion of the work table in Figure 1 is provided with a number of rollers 20 which allow of telescopic movement relative to a stationary supply conveyor 21.
  • the work table 3 terminates above a delivery conveyor 22.
  • a combined drive through the motors 11 and 16 any desired movement can be realized of the work table 3 in a horizontal direction and of the supporting beams 4 with the parts mounted in between to be described hereinafter in a vertical direction.
  • these drives may be operated under numerical control.
  • Figure 3 is top view of a substantially U-shaped frame consisting of two longitudinal bars 30 connected by a cross bar 31.
  • Each bar 30 is provided with two coupling flanges 32 to permit mounting between the supporting beams 4 by means of the coupling flanges 14 mounted thereon.
  • the longitudinal bars 30 are of the box type and each provided with a fan with motor 33 for the supply of cooling air to each bar 30.
  • a rocker arm 35 At the side of each bar 30 a rocker arm 35 has been fitted. The rocker arms 35 move synchronously in opposite directions.
  • a support 36 is provided for tension bars 37.
  • a filament 40, a tension spring 41 and two terminal pull cables 42, 43 are invariably mounted between the two tension bars (see figure 6).
  • the hollow bar is provided with discharge openings 45. Cold air supplied flows through these openings and thereby cools the part of the filaments 40 that projects from a block 46 to be cut.
  • a lever 50 On the end of the rocker arms 35 that is located near the cross bar 31 a lever 50 has been mounted. The tip of this lever rests at 51 on an eccentric 52 which forms part of a short axle provided with a gear wheel 53.
  • the two gear wheels 53 are interconnected by a rubber driving belt 54 which is provided with an internal toothing and which is held under initial tension by means of a movable thrust collar 55.
  • the eccentric shaft mounted on the right-end side in Figure 4 is driven by a motor 56 (see also Figure 3).
  • a synchronous displacement of the two rocker arms is accomplished by the use of a toothed belt.
  • the initial tension of the several springs 41 ensures that the levers 50 continuously lie against the eccentric 52.
  • the work table is designed for receiving a block of starting material at least four metres long. It is also possible to process blocks of starting material twelve metres long by running such blocks through the apparatus in three passes.
  • the block of starting material can be pushed on to position 60, it being understood that its front will have been profiled in accordance with the contours of the cut products, and subsequently a corresponding number of products can be cut by a substantially upward movement of the U-shaped frame, to be followed by a third series of products made from the block of starting material.
  • oscillating contour cutting can be practised not only on thermoplastic synthetics such as polystyrene foam, but also on rigid foam material such as polyurethane.
  • the surface so obtained is smooth and comparable to that produced by mechanical sawing, but without any sawdust being formed.
  • Cutting according to the invention involves a material loss of at most 1 mm, whilst the cutting speed attainable for, say, rigid polystyrene foam may be as much as four metres per minute.
  • the temperature of the filament is set to a value of 80 to 90°C, but, depending on the resistance of the material to be cut, a higher equilibrium temperature may be reached on account of the friction.
  • An effective straight cut proves to be feasible at an average initial tension of the filaments of 10 kg.

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  • Life Sciences & Earth Sciences (AREA)
  • Forests & Forestry (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Perforating, Stamping-Out Or Severing By Means Other Than Cutting (AREA)
  • Processing And Handling Of Plastics And Other Materials For Molding In General (AREA)
  • Details Of Cutting Devices (AREA)

Abstract

Apparatus for contour cutting of a number of uniform plastic products from a block of starting material by means of a plurality of parallel filaments heated by an electric current, provided with a work table (3) that is movable in a horizontal direction for receiving at least part of a block of starting material, a supply conveyor (21) and a delivery conveyor (22), a number of vertical columns (2), a horizontal U-shaped framework that is mounted between two horizontal supporting beams (4), which framework is provided with a number of parallel cutting filaments and is movable up and down in a vertical direction along the columns (2), driving means (16) for the working table, driving means (11) for the supporting beams with the U-shaped frame, and means for imparting a synchronous oscillating movement of each of the filaments in the U-shaped frame in their long direction.

Description

  • The invention relates to a method for simultaneously contour cutting a plurality of identical uniform plastic products from a single block of starting material, using a plurality of filaments disposed in parallel array for engagement of said single block and heated by an electric current, the filaments being given an oscillating movement along their longitudinal axis, the starting material being given a movement in the horizontal direction and at least some of the filaments being given a synchronised alternating movement in the vertical direction.
  • The invention also relates to an apparatus for simultaneously contour cutting a plurality of identical uniform plastic products from a single block of starting material, according to the above method, comprising a work table movable substantially in a horizontal direction for receiving at least a part of a block of starting material, a drive mechanism for horizontal movement of the work table, a number of substantially vertical columns, a framework supporting a plurality of electrically heated filaments in parallel array as cutters for said block of starting material, a drive for imparting an oscillating movement to the filaments along their longitudinal axis, and drive means for imparting alternating vertical movement synchronised with the horizontal movement to at least some of the filaments.
  • Such a method and apparatus are known from US―A―3 786 701 in which a method and apparatus are disclosed for simultaneously contour cutting a plurality of identical uniform plastic products from a single block of starting material, using a plurality of filaments disposed in parallel array and heated by an electric current, the filaments being given an oscillating movement along their longitudinal axis and the starting material being given a movement in the horizontal direction, and at least some of the filaments being given a synchronised alternating movement in the vertical direction. This known method and apparatus are only intended for cutting during motion of the supporting platform in one single direction, and the framework in which two sets of parallel cutting filaments are mounted is given an oscillating movement as a whole. One set of parallel cutting filaments is directly connected to the frame by means of longitudinally aligned springs, while a second set of parallel cutting filaments is connected to movable bars by means of springs in which the movable bars move vertically in the plane of mounting of the filaments and are directly controlled by guide wheels, following patterns which are fixedly connected to the apparatus.
  • It is the object of the present invention to provide an improved method of the type specified above, in which a plurality of contoured products of an intricate form can be obtained and in which each simultaneously cut product has identical dimensions and has a substantially identical form over its entire width and in which at least some parts of the contour are cut in an opposite direction compared to adjacent parts of the contour, as well as an improved apparatus for carrying out such a method.
  • To this end according to the invention it is proposed, starting from a method of the type specified above, that the array of filaments is maintained in a common horizontal plane during cutting whereby said array has imparted to it an alternating programmed movement in the vertical direction, and a correspondingly programmed alternating movement is imparted to the block of starting material in the horizontal direction, thus defining in combination a prescribed cutting contour of each filament relative to the block of starting material. By means of such correspondingly programmed alternating movements a plurality of virtually identical products, depending on the number of filaments used, is obtained from a single block of starting material. The products obtained have a uniform profile or contour over the whole width of the products cut, while a sharp cornered contour can be obtained.
  • According to the invention, an apparatus of the type indicated above is characterized in that the framework is U-shaped and is disposed substantially in a horizontal plane such that the array of filaments is supported in a common horizontal plane, the drive for longitudinal oscillation of the filaments being adapted to oscillate the filaments within said U-shaped frame, in that the driving means for alternating vertical movement of the array of filaments are adapted to move the U-shaped framework up and down along the vertical columns according to a program thus transporting the plane of the filament array vertically, and in that the drive mechanism for horizontal movement of the work table is provided with a program for the horizontal alternating displacement of the work table, such that in combination with the programmed movement of the framework, the filaments follow a prescribed cutting contour relative to the block of starting material. By oscillating all filaments along their longitudinal axis within the U-shaped framework a nearly vibration-free drive is obtained. By oscillating all filaments in a common horizontal plane and by giving the U-shaped framework an alternating vertical movement sharp-cornered products are obtained.
  • It is remarked that in FR-A-1 355 283 a method is disclosed for contour cutting a plurality of uniform plastic products from a block of starting material, using a plurality of filaments disposed in parallel array and heated by an electric current, in which the block of starting material is given a programmed alternating movement, that is substantially parallel to the plane of the filaments. However, according to this method the filaments are only given a vertical movement, which is not alternating when the method is carried out, and the corresponding programmed movement in the horizontal direction of the block of starting material is obtained by means of a cammed wheel, by which it is only possible to obtain a quite simple form of contour. By carrying out such a method adjacent parts of the contour cannot be cut in an opposite direction. Owing to the use of cammed wheels only a slight alteration of the direction of the cut can be obtained, as can be seen from figures 5 and 7 of this publication. Furthermore, according to this publication, no reciprocating movement of the filaments is proposed and the method can only be used for a quite restricted height of the block of starting material.
  • It is furthermore remarked that in EP-A-0 035 852 an apparatus for contour cutting is described using four vertical columns disposed around the work table to support and guide a U-shaped framework, each column being provided with drive means for the vertical displacement of that part of the framework supported by the column. In this known apparatus use is made of an endless cutting wire rotating on discs, and the framework, in which the cutting wire has been mounted, is given a movement in one direction, and the product to be cut a movement at right angles to the first movement. It is possible, by using this apparatus, to cut at most two blocks of material into a shape having a desired contour. However, this apparatus for cutting two identical products at the same time is already quite complicated, and it cannot be seen how an increased number of products could easily be cut at the same time.
  • Further particulars of the invention also become apparent from the following description of an embodiment of apparatus according to the invention.
  • In the drawings:
    • Figure 1 is a schematic side view of an apparatus according to the invention;
    • Figure 2 is a top view of the same apparatus;
    • Figure 3 is a detailed top view of a U-shaped frame;
    • Figure 4 is an end view on IV-IV in figure 3;
    • Figure 5 is a sectional view on V-V in figure 3;
    • Figure 6 depicts a section along the line VI-VI in figure 3 on an enlarged scale; and
    • Figure 7 shows a few products.
  • The apparatus depicted in Figure 1 comprises a base frame 1 on which four vertical columns 2 have been mounted in a rectangle. Enclosed within the columns is a work table 3. In the long direction of the apparatus a supporting beam 4 has been provided at both ends. These supporting beams are suspended on vertical carrier heads 5 which can be moved along the columns 2. Each of the carrier heads 5 is connected through a chain 6 and a sheave 7 with a counterweight 8. The load of this counterweight 8 is chosen such that it virtually compensates the load of the framework with supporting beams and any other components fitted to it weighing on each carrier head 5. Each of the carrier heads 5 can be displaced in a vertical direction by driving means - not shown in the drawings - moving synchronously for each carrier head, such as a screw spindle with nut. All these driving means are linked together for the four columns by means of drive shafts 9 and 10 in the longitudinal and crosswise direction, respectively.
  • A drive motor is denoted by 11. Obviously, more drive motors may be applied, provided a vertically uniform displacement of the carrier heads is ensured. The columns are connected together at the top by means of structural shapes 12 and 13, respectively.
  • Each of the supporting beams 4 is provided at the location of a vertical column 2 facing the carrier head with a coupling flange 14 for the attachment of the U-shaped framework to be discussed below. On the base frame 1, a screw spindle 15 with driving motor 16 has been mounted underneath the work table 3. This screw spindle meshes with a nut incorporated into a support 17 underneath the work table 3. By means of schematically shown carrier wheels 18, the work table 3 rests on guiding tracks 19. The motor 16 enables the work table 3 to be moved to and fro over a distance of about two metres. The left-hand portion of the work table in Figure 1 is provided with a number of rollers 20 which allow of telescopic movement relative to a stationary supply conveyor 21. On the right-hand side, the work table 3 terminates above a delivery conveyor 22. By a combined drive through the motors 11 and 16, any desired movement can be realized of the work table 3 in a horizontal direction and of the supporting beams 4 with the parts mounted in between to be described hereinafter in a vertical direction. Optionally, these drives may be operated under numerical control.
  • Figure 3 is top view of a substantially U-shaped frame consisting of two longitudinal bars 30 connected by a cross bar 31. Each bar 30 is provided with two coupling flanges 32 to permit mounting between the supporting beams 4 by means of the coupling flanges 14 mounted thereon. The longitudinal bars 30 are of the box type and each provided with a fan with motor 33 for the supply of cooling air to each bar 30. At the side of each bar 30 a rocker arm 35 has been fitted. The rocker arms 35 move synchronously in opposite directions. On top of the rocker arm 35 a support 36 is provided for tension bars 37. A filament 40, a tension spring 41 and two terminal pull cables 42, 43 are invariably mounted between the two tension bars (see figure 6). As the bars 37 move away from one another, the increased distance will be accommodated by an elongation of the tension spring 41. In the embodiment according to figure 6, the bottommost filament 40 will then move to the left. A large number of wires, say 50, have been strecthed between the two rocker arms 35 in the manner indicated, such that the tension spring 41 is alternately attached to either one of the tension bars. In consequence, when the tension bars 37 move outwards, one half of the filaments 40 travel to the left and the other half of the filaments to the right, and when the tension bars move back inwards these filaments will each travel in opposite direction.
  • As the forces exerted by the several filaments are oriented in opposite directions, the resulting force on the material to be processed will be virtually nil.
  • As appears from figure 6 in particular, the hollow bar is provided with discharge openings 45. Cold air supplied flows through these openings and thereby cools the part of the filaments 40 that projects from a block 46 to be cut.
  • For the synchronous drive of the tension bars on the rocker arms 35, reference is made to the terminal view of figure 4.
  • On the end of the rocker arms 35 that is located near the cross bar 31 a lever 50 has been mounted. The tip of this lever rests at 51 on an eccentric 52 which forms part of a short axle provided with a gear wheel 53. The two gear wheels 53 are interconnected by a rubber driving belt 54 which is provided with an internal toothing and which is held under initial tension by means of a movable thrust collar 55. The eccentric shaft mounted on the right-end side in Figure 4 is driven by a motor 56 (see also Figure 3). A synchronous displacement of the two rocker arms is accomplished by the use of a toothed belt. The initial tension of the several springs 41 ensures that the levers 50 continuously lie against the eccentric 52.
  • It has been found that an efficient, vibrationproof drive of the whole can be achieved by maintaining an initial tension for the two rocker arms 35 relative to the U-shaped framework such that the overall tension of the springs 41 is substantially compensated provided that sufficient force is at all times preserved for the levers 50 to lie against the eccentrics 51. Depending on the requisite driving frequency, the initial tension may be adapted.
  • The work table is designed for receiving a block of starting material at least four metres long. It is also possible to process blocks of starting material twelve metres long by running such blocks through the apparatus in three passes.
  • By the application of fifty cutting wires between the two rocker arms, forty-nine pieces can be cut at a time in one vertical movement. This is illustrated in Figure 7, where the dot-dash line represents the contour of a block to be cut. A number of successive cutting wires are denoted by A', N, 0. The block to be cut is placed with its foremost boundary line at the desired distance. Next, the cut A'-A is made by a vertical displacement of the U-shaped framework. All the other cutting wires perform a corresponding cut. Then, a combined displacement of the work table in a horizontal plane and of the filaments in the U-shaped frame upwards takes place for the cut A-B and the corresponding cuts of the other filaments. Subsequently, a horizontal displacement is continued in the same direction, whereas the U-shaped frame moves down, so that the cut B-C is carried out. Thereupon, the vertical displacement is continued but the work table inverts the direction of travel for the cut C-D to be made. Next to follow is the cut D-E, upon inversion of the direction of travel of the work table, and then the cut E-F, again requiring inversion of the direction of travel of the work table. Finally, a cut F-G is made, whereupon the U-shaped frame moves down to the indicated G'. In this position the filaments 40 have all come to rest in local recesses 70 in the work table 3.
  • As the consecutive wire N has in the mean time gone through a corresponding movement along the points A, K, L, G to N', the foremost product has been cut loose with one vertical movement of the U-shaped frame, and as a matter of course so have all the other forty-nine products.
  • Thereupon, the block of starting material can be pushed on to position 60, it being understood that its front will have been profiled in accordance with the contours of the cut products, and subsequently a corresponding number of products can be cut by a substantially upward movement of the U-shaped frame, to be followed by a third series of products made from the block of starting material.
  • It is worth noting that a very sharp cut is obtained by the use of oscillating filaments with hardly any deflection of the filament. As a result, it is possible to produce clear-cut contours over the entire width of the block to be processed, even when acute angles are cut as in the example of Figure 7. In the cutting of angles, therefore, the cutting speed need hardly be reduced, although this is easily done, if desired. In this fashion, products are obtained with a sharply profiled appearance. In this case of thermoplastic starting material, all cells at the surface of cut are sealed by annealing, affording an extremely smooth appearance, because no dust is formed during cutting which could roughen the surface.
  • It has been found that oscillating contour cutting can be practised not only on thermoplastic synthetics such as polystyrene foam, but also on rigid foam material such as polyurethane. The surface so obtained is smooth and comparable to that produced by mechanical sawing, but without any sawdust being formed. Cutting according to the invention involves a material loss of at most 1 mm, whilst the cutting speed attainable for, say, rigid polystyrene foam may be as much as four metres per minute. The temperature of the filament is set to a value of 80 to 90°C, but, depending on the resistance of the material to be cut, a higher equilibrium temperature may be reached on account of the friction. An effective straight cut proves to be feasible at an average initial tension of the filaments of 10 kg.

Claims (6)

1. A method for simultaneously contour cutting a plurality of identical uniform plastic products from a single block of starting material, using a plurality of filaments (40) disposed in parallel array for engagement of said single block and heated by an electric current, the filaments (40) being given an oscillating movement along their longitudinal axis, the starting material being given a movement in the horizontal direction and at least some of the filaments being given a synchronised alternating movement in the vertical direction, characterized in that the array of filaments is maintained in a common horizontal plane during cutting whereby said array has imparted to it an alternating programmed movement in the vertical direction, and a correspondingly programmed alternating movement is imparted to the block of starting material in the horizontal direction, thus defining in combination a prescribed cutting contour of each filament relative to the block of starting material.
2. Apparatus for simultaneously contour cutting a plurality of identical uniform plastic products from a single block of starting material, according to the method of claim 1, comprising a work table (3) movable substantially in a horizontal direction for receiving at least a part of a block of starting material, a drive mechanism (15, 16, 17) for horizontal movement of the work table, a number of substantially vertical columns (2), a framework (30, 31) supporting a plurality of electrically heated filaments (40) in parallel array as cutters for said block of starting material, a drive (56, 54, 52, 53, 51, 50, 35, 36, 37) for imparting an oscillating movement to the filaments along their longitudinal axis, and drive means (11, 9, 10) for imparting alternating vertical movement synchronised with the horizontal movement to at least some of the filaments (40), characterized in that the framework (30, 31) is U-shaped and is disposed substantially in a horizontal plane such that the array of filaments (40) is supported in a common horizontal plane, the drive for longitudinal oscillation of the filaments being adapted to oscillate the filaments within said U-shaped frame, in that the driving means (11, 9, 10) for alternating vertical movement of the array of filaments are adapted to move the U-shaped framework up and down along the vertical columns (2) according to a program thus transporting the plane of the filament array vertically, and in that the drive mechanism (16, 15, 17) for horizontal movement of the work table is provided with a program for the horizontal alternating displacement of the work table (3), such that in combination with the programmed movement of the framework, the filaments follow a prescribed cutting contour relative to the block of starting material.
3. Apparatus according to claim 2, characterized in that it is provided with four vertical columns (2) disposed round the work table (3)- in a rectangle for supporting and guiding the U-shaped framework (30, 31), each column being provided with drive means (11) for the vertical movement of that part of the framework supported by that column, whilst the drive means of all four columns are connected together for a synchronous movement, each column also comprising a counterweight (8) arranged to provide substantially total counterbalancing of that part of the weight of the U-shaped framework, with components mounted on it, which is supported by the appropriate column.
4. Apparatus according to either one of claims 2 and 3, characterized in that each filament (40) is connected to a tension spring (41) such that filament and tension spring are continuously stretched between two tension bars (37) mounted parallel to one another within the U-shaped framework, which tension bars can be moved synchronously to and fro in opposite directions thus imparting a reciprocating movement to the filaments, whilst the tension springs fitted to successive filaments are preferably attached alternately to one or other of the tension bars.
5. Apparatus according to claim 4, characterized in that each tension bar (37) is mounted on a rocker arm (35) of which is rotationally supported on one of the two parallel side bars (30) of the U-shaped framework (30, 31), and is provided near the cross bar (31) of the U-shaped framework with a stretching device (51, 52, 53) and a lever (50), which lever is caused by the tension of the filaments (40), tension springs (41) and the stretching device (51, 52, 53) to rest against an eccentric (52) forming part of the respective stretching device (51, 52, 53), the eccentric on either side of the U-shaped framework being mounted on a shaft driven by means of a common driving motor (56) and a toothed belt (54), such that the corresponding tension bar (37) on its rocker arm (35) alternates in a sense opposite to that of the tension bar (37) facing it on the other side of the U-shaped frame.
6. Apparatus according to any one of claims 2 to 5, characterized in that the work table (3) is provided with a plurality of grooves (70) made in crosswise direction for receiving the filaments (40) in the bottommost position of the U-shaped framework.
EP83200884A 1982-06-16 1983-06-16 Method and apparatus for contour cutting of plastic products Expired EP0097992B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT83200884T ATE24682T1 (en) 1982-06-16 1983-06-16 METHOD AND DEVICE FOR CONTOUR CUTTING OF PLASTIC PRODUCTS.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
NL8202437 1982-06-16
NL8202437A NL8202437A (en) 1982-06-16 1982-06-16 METHOD AND APPARATUS FOR CONTOUR CUTTING OF PLASTIC PRODUCTS, AND IMPROVED CONTOUR CUTTING PRODUCTS.

Publications (2)

Publication Number Publication Date
EP0097992A1 EP0097992A1 (en) 1984-01-11
EP0097992B1 true EP0097992B1 (en) 1987-01-07

Family

ID=19839892

Family Applications (1)

Application Number Title Priority Date Filing Date
EP83200884A Expired EP0097992B1 (en) 1982-06-16 1983-06-16 Method and apparatus for contour cutting of plastic products

Country Status (4)

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EP (1) EP0097992B1 (en)
AT (1) ATE24682T1 (en)
DE (1) DE3368888D1 (en)
NL (1) NL8202437A (en)

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NL8500525A (en) * 1985-02-25 1986-09-16 Dijk Bv Gebr Van METHOD AND APPARATUS FOR CONTOUR CUTTING
FR2665100A1 (en) * 1990-07-27 1992-01-31 Croma Sarl METHOD AND APPARATUS FOR CUTTING BLOCKS AND PLATES OF CELLULAR SYNTHETIC MATERIALS.
WO1995034354A1 (en) * 1994-06-16 1995-12-21 Giovanni Lavermicocca Three-dimensional puzzles
US5950512A (en) * 1996-10-11 1999-09-14 Gary D. Fields Apparatus to make building blocks for blockwork domed structures, and method and domed structure
DE29801499U1 (en) * 1998-01-30 1999-06-02 Kurtz Altaussee Gmbh, Altaussee Cutting device for cutting thermally processable material
FR2787376B1 (en) * 1998-12-22 2001-03-09 Esox METHOD AND INSTALLATION FOR CUTTING PARTS OF ANY SHAPE
ITVR20120072A1 (en) * 2012-04-13 2013-10-14 Oms Automation S R L CUTTING DEVICE FOR LASTRIFORMS ELEMENTS FOR THE PRODUCTION OF PANELS IN EXPANDED PLASTIC MATERIAL
CN115194892B (en) * 2022-07-28 2023-11-28 无锡焙斯机械有限公司 Butter cutting machine

Citations (1)

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Publication number Priority date Publication date Assignee Title
US3786701A (en) * 1971-11-05 1974-01-22 E Ludwig Device for cutting urethane foam

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Publication number Priority date Publication date Assignee Title
US3089526A (en) * 1960-06-23 1963-05-14 Lykkeberg Alfred Machine for slicing meat
FR1355283A (en) * 1963-04-29 1964-03-13 Simoniz Co Cutting machine
BE754761A (en) * 1970-08-12 1971-01-18 Vossen Claude Slicing meat
AU7815375A (en) * 1974-02-27 1976-08-12 Treffner P Method and apparatus for cutting plastics materials
AU4306579A (en) * 1978-01-09 1979-07-19 Charles Treffner Multi-bladed cutting apparatus
US4175455A (en) * 1978-03-22 1979-11-27 Mcneil Corporation Travelling cut-off saw
EP0035852A3 (en) * 1980-02-27 1981-09-23 J. MacA. King & Co., Limited Contour cutters

Patent Citations (1)

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Publication number Priority date Publication date Assignee Title
US3786701A (en) * 1971-11-05 1974-01-22 E Ludwig Device for cutting urethane foam

Also Published As

Publication number Publication date
ATE24682T1 (en) 1987-01-15
DE3368888D1 (en) 1987-02-12
NL8202437A (en) 1984-01-16
EP0097992A1 (en) 1984-01-11

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