(19)
(11) EP 1 864 767 B1

(12) EUROPEAN PATENT SPECIFICATION

(45) Mention of the grant of the patent:
02.12.2009 Bulletin 2009/49

(21) Application number: 06115239.3

(22) Date of filing: 09.06.2006
(51) International Patent Classification (IPC): 
B26D 1/40(2006.01)
B26D 1/62(2006.01)

(54)

Method and device for cutting material comprising gypsum

Verfahren und Vorrichtung zum Schneiden von gipsartigem Schneidgut

Procédé et appareil pour la coupe des materiaux comprenant gypse


(84) Designated Contracting States:
AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IS IT LI LT LU LV MC NL PL PT RO SE SI SK TR

(43) Date of publication of application:
12.12.2007 Bulletin 2007/50

(73) Proprietor: Aliatool AB
459 22 Ljungskile (SE)

(72) Inventor:
  • Giaever, Stig Asbjörn
    459 93 Ljungskile (SE)

(74) Representative: Vink, Charlotta et al
AWAPATENT AB Södra Hamngatan 37-41 Box 11394
404 28 Göteborg
404 28 Göteborg (SE)


(56) References cited: : 
DE-A1- 2 626 151
US-A1- 2003 121 381
US-A- 3 380 328
   
       
    Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention).


    Description

    Technical Field



    [0001] The present invention relates to a method for cutting material comprising gypsum. Furthermore, the invention relates to a gypsum-cutting device.

    Technical Background of the Invention



    [0002] Within the construction industry, it has been generally known to use plasterboards for the construction of non-load carrying dividing walls and as interior/exterior cladding in connection with renovation and/or insulation of exterior walls.

    [0003] Plaster boards of the type described above has a number of advantageous features such as fire retardant, noise insulating and relatively simple to mount. These characteristics in addition to a relatively low square meter price have made this type of plaster boards relatively wide used.

    [0004] Due to increased prices on the raw materials as well as stricter environmental demands, especially regarding storage on the landfill sites, the feasibility of reusing materials has become economically viable. Another driving force is that the price of storage varies enormously and it is especially expensive for mixed waste. Therefore, a higher degree of separation is desirable such that a major part of the waste material may be stored in a non-mixed landfill where it is less costly than in a mixed landfill. The method and the gypsum plasterboard-cutting device according to the present invention may be used for any type of waste material comprising gypsum. Generally, there exist three types of plasterboard waste:
    1. 1, cut-aways resulting from construction work where plasterboards are cut to fit,
    2. 2, new plasterboard with quality problems resulting from the manufacturing process, and
    3. 3, waste from demolition work.


    [0005] Thus, it is realised that there is a need to improve the handling of waste material comprising gypsum, especially at construction sites. There exist in the art a cutting device which has an inlet for said plasterboards and one roller around which spaced apart cutting edges are provided, said cutting device also comprises cutting edges for performing a cutting operation of said plasterboard in a longitudinal and a transverse direction in relation to a feeding direction of the plasterboard. However, the manner in which the cutting is performed is considered rather energy consuming since the transverse cutting force is applied once per revelation of the roller in question leading to a high impact of the system.

    [0006] Furthermore, since conventional plasterboards are provided with paper on each side the cutting operation according to the state of the art is not always sufficient since the resulting plasterboard-pieces are still connected and thus not easily compactly stacked after cutting. Thus, it is an issue to provide an improved cutting method and at the same time, possibly, lower the energy demand for performance of said method. Since, small particles of gypsum easily mix with dirt and dust it is desirable to enable a cutting operation with a clean cut and a suitable plasterboard size once cut.

    [0007] Rollers with a spiral cutting edge have been known for reducing forces in a variety of applications, see for example US 3,380,328.

    Summary of the Invention



    [0008] The fundamental idea of the invention is to solve the problems outlined above and to enable a rapid and efficient cutting of waste material comprising gypsum, preferably plasterboard.

    [0009] A further object of the invention is to suggest a method and a device enabling cleaner cut and a suitable resulting non-mixed product in the noisy and dusty environment of a construction site.

    [0010] In accordance with the teachings of the invention these objects are obtained by means of the cutting device defined in the appended claim 7 and the cutting method defined in the appended claim 1. Preferred embodiments of the device are defined in the dependent claims 8-14.

    [0011] Preferably, the plasterboard being cut when introduced in between at least two complementary arranged spiral cutting edges, wherein at least one is provided on respective roller.

    [0012] Said cutting method has the benefit of enabling a compact recyclable gypsum product. In addition the clean cutting method reduces the amount of small particles and hence the risk of mixing with other material particles which would make it difficult to recycle. This is foreseen to be an issue in today's building industry which is often dusty and full of small particles of various materials. Another benefit associated to the compact handling of the resulting plasterboard-pieces is that the required amount of containers may be kept at a minimum as well as the number of freights of the resulting material since the volume is significantly reduced.

    [0013] Advantageously, the peripheral speed of the complementary spiral cutting edges are equal during cutting so that the respective part of the spiral cutting edges faces one another when in their nearest position to one another. It is realised that this nearest position of the oppositely arranged spiral cutting edges changes during rotation of the same and thus a cut in the paper layer of the plasterboard all along the width of the plasterboard is rapidly accomplished without the necessity to increase the force or impact. The pressure from oppositely arranged cutting edges is also sufficent to enable the gypsum itself to give in during performance of the cutting method.

    [0014] According to the invention, the rollers are movable in a tensioned manner in relation to one another such that plasterboards of different thicknesses may be cut.

    [0015] Suitably, the rollers are held by pivotable holder elements. The cutting operation is performed by a motorized cutting device.

    [0016] Advantageously, the resulting plasterboard pieces are collected in a recycling-container. Plasterboard generally consist of paper on each side and gypsum in between. The thickness of the plasterbords are normally ranging between 6 and 22 mm, and typically around 12 mm, although there exist extremes.

    [0017] There is also according to the invention provided a cutting device for cutting material comprising gypsum, as defined in claim 7.

    [0018] Preferably, complementary arranged spiral cutting edges are provided on a respective roller such that said plasterboard being cut when introduced in between two complementary arranged spiral cutting edges provided on a respective roller.

    [0019] Advantageously, the peripheral speed of the complementary spiral cutting edges are equal during cutting so that the respective part of the spiral cutting edges faces one another when in their nearest position.

    [0020] According to the invention, the rollers are movable in a tensioned manner in relation to one another such that plasterboards of different thicknesses may be cut. Suitables, the rollers are held by pivotable holder elements. Said cutting device is motorized.

    [0021] The peripheral speed of the complementary spiral cutting edges arranged on opposite rollers are equal during cutting so that the respective part of the spiral cutting edges faces one another when in their nearest position in relation to one another.

    [0022] Suitably, any one of said cutting edges is arranged such on the roller that the resulting plasterboard-pieces have a side length of between 2 to 35 cm, preferably 5 to 20 cm and more preferably around 10 to 15 cm. Moreover, any one of said cutting edges has a height of 2-10 mm and preferably 3-6 mm. The cutting edges are exchangeable such that worn out or damaged cutting edges may easily be replaced, e.g. by screwing on new cutting edges. The spiral cutting edge is advantageously tooth-shaped.

    [0023] By combining characteristic features of different alternative embodiments of the invention described herein additional possible varieties may be obtained that are within the scope of the claims. It is considered to be within the competence of the expert in the field to choose a suitable motor to provide suitable embodiments within the scope of the invention.

    Brief Description of the Drawings



    [0024] The method of the present invention as well as examples of embodiments of a device for performing the method will be described in the following in more detail with reference to the accompanying drawing. In the drawing:

    Fig 1 is a schematic perspective view of the cutting device,

    Fig 2 is a schematic perspective view of an enlarged embodiment of a roller,

    Fig 3 is an exploded perspective view of a part of the cutting device shown in more detail,

    Fig 4 is perspective view of a part of the cutting device,

    Fig 5 is a side view of the cutting device in accordance with Fig 4.


    Detailed Description of Preferred Embodiments



    [0025] One preferred embodiment of the invention will be described in the following with reference to the accompanying drawings.

    [0026] Fig 1 shows a cutting device 1 in accordance with a preferred embodiment of the invention. The cutting device 1 comprises an inlet 15 for said plasterboards 1. The inlet 15 is preferably about 1 meters wide in order to fit most shapes of waste plasterboard. The cutting device 10 is provided with a supporting structure which may carry wheels. According to a preferred embodiment (not shown) the cutting device 10 may be folded in order to save space during transport etc. The cutting device comprises cutting edges 25 for performing at least one cutting operation of said plasterboard 1 in a longitudinal and an essentially transverse direction in relation to a feeding direction of the plasterboard 1.

    [0027] With reference to fig 3 it is disclosed that a spiral cutting edge 25 is provided around said at least one roller 11. There are complementary arranged spiral cutting edges 25, 25' provided on a respective roller 11, 11' such that said plasterboard 1 being cut when introduced in between two complementary arranged spiral cutting edges 25, 25' provided on a respective roller 11, 11'. The peripheral speed of the complementary spiral cutting edges 25; 25' arranged on opposite rollers are equal during cutting so that the respective part of the spiral cutting edges 25, 25' faces one another when in their nearest position in relation to one another. At least one of said cutting edges 13, 13'; 25, 25' is arranged such on the roller 11, 11' that the resulting plasterboard-pieces have a side length of between 2 to 35 cm, preferably 5 to 20 cm and more preferably around 10 to 15 cm after the cutting operation. Furthermore, any one of said cutting edges 13, 13'; 25, 25' has a height of 2-10 mm and preferably 3-6 mm.

    [0028] Preferably, any one of said cutting edges 13, 13'; 25, 25' is tooth-shaped.

    [0029] Now, with reference to fig 4 and 5 further features and advantages will be explained. The cutting device has rollers 11, 11' that are movable in a tensioned manner in relation to one another such that plasterboards 1 of different thicknesses may be cut. The tension in the cutting device is accomplished by attached springs and interposed holder elements 23, 23'.

    [0030] Furthermore, the rollers 11, 11' are held by pivotable holder elements 16, 16'. The cutting device 10 is suitably motorized. Driving wheels 18, 18' are interconnected with the motor through a shaft (not shown). The rollers 11, 11' are rotated by the driving wheels 18, 18' via drive belts 19, 19' and roller wheels 17, 17' .

    [0031] In accordance with a preferred embodiment, the cutting device 10 is provided with safety means of standard type, such as emergency stop means, two-hand control devices and no-voltage circuit breakers. As will be appreciated, the method of cutting the plasterboard 1 may be implemented by making the cutting device 10 operate in a more or less automated way.



    [0032] With reference now to fig 2 it is disclosed a roller 11 according to a preferred embodiment. The roller 11 comprises a spiral recess 12 along the elongated axis of said roller 11. The spiral recess 12 preferably has an inclination corresponding to one twist around the roller 11 along its propagation. Although other helical angles may be suitable the at least one whole turn around the roller is preferred for the spiral cutting edge 25, 25'/ edges. This will allow the two oppositely arrange spiral cutting edges to start from facing pair position regardless of starting point. Furthermore, the spiral recess is adapted to host a spiral cutting edge 25, 25' (not shown in fig 2). For this purpose there is provided holes for fastening the spiral cutting edge by screws or similar means. It is also disclosed a first cutting edge 13 around the roller 11. The first cutting edge 13 propagetes in the revelation direction of the roller 11 and thus provides for the longitudinal cuts or substantially longitudinal cuts, when there is a deviation in the propagating direction of the first cutting edge 13 from a normal direction in relation to the elongated axis of the roller 11.

    [0033] As will be appreciated, some of the characteristic features defined above may be combined in various ways to form additional embodiments within the scope of protection of the invention. The method and the device in accordance with the invention are thus not restricted to what has been shown and described herein. The invention thus may be modified further in several ways within the scope of the appended claims.

    [0034] The device is for example applicable also to armoured plasterboards of various thickness. When armoured plasterboards are used, these should be regarded as included in the concept of plasterboards as referred to herein. Further preferred embodiments of the invention thus may be created by providing the cutting device with additional equipment within the scope of what the expert in the field considers to be obvious, such as containers 3 of different kinds, not shown in detail. Examples of containers are sacks or carriage. By combining characteristic features of different alternative embodiments of the invention described herein additional possible varieties may be obtained that are within the scope of the claims. It is considered to be within the competence of the expert in the field to choose a suitable motor to provide suitable embodiments within the scope of the invention.


    Claims

    1. A method of cutting material comprising gypsum, preferably plasterboards. (1),
    said method comprising the steps of:

    feeding a cutting device (10) with said plasterboards (1), said cutting device (10) comprising at least one roller (11) around which spaced apart cutting edges (13) are provided,

    said method further comprises the step of performing at least one cutting operation of said plasterboard (1) in a longitudinal and an essentially transverse direction in relation to a feeding direction, said method being

    characterised in that said essentially transverse cut is accomplishable, with a spiral cutting edge (25) provided around said at least one roller (11), during rotation of said roller (11) and in that the rollers are movable in a tensioned manner in reflation to one another such that plasterboards of different thicknesses may be cut.
     
    2. The method according to claim 1, in which said plasterboard (1) being cut when introduced in between two complementary arranged spiral cutting edges (25, 25') provided on a respective roller (11, 11').
     
    3. The method according to any one of the preceding claims, in which method the peripheral speed of the complementary spiral cutting edges (25; 25') are equal during cutting so that the respective part of the spiral cutting edges (25, 25') faces one another when in their nearest position in relation to one another.
     
    4. The method according to any one of the preceding claims, in which the rollers (11, 11') are held by pivotable holder elements (16, 16').
     
    5. The method according to any one of the preceding claims, in which the cutting operation is performed by a motorized cutting device (10).
     
    6. The method according to any one of the preceding claims, in which the resulting plasterboard pieces (2) are collected in a recycling-container (3).
     
    7. A cutting device (10) for cutting material comprising gypsum, preferably plasterboards (1), said cutting device (10) comprising an inlet (15) for said plasterboards (1) and at least one roller (11), said cutting device (10) comprises cutting edges for performing at least one cutting operation of said plasterboard (1) in a longitudinal and an essentially transverse direction in relation to a feeding direction of the plasterboard, said cutting device (10) comprises a spiral cutting edge (25) provided around said at least one rollers (11),
    characterized in that the rollers (11, 11') are movable in a tensioned manner in relation to one another such that plasterboards (1) of different thicknesses may be cut.
     
    8. The cutting device (10) according to claim 7, wherein complementary arranged spiral cutting edges (25, 25') are provided on a respective roller (11, 11') such that said plasterboard (1) being cut when introduced in between two complementary arranged spiral cutting edges (25, 25') provided on a respective roller (11, 11').
     
    9. The cutting device (10) according to any one of the preceding claims 7-8, wherein the peripheral speed of the complementary spiral cutting edges (25; 25') are equal during cutting so that the respective part of the spiral cutting edges (25, 25') faces one another when in their nearest position.
     
    10. The cutting device (10) according to any one of the preceding claims 7-9, wherein the rollers (11, 11') are held by pivotably holder elements (16, 16').
     
    11. The cutting device (10) according to any one of the preceding claims 7-10, wherein said cutting device (10) is motorized.
     
    12. The cutting device (10) according to any one of the preceding claims 7-11, wherein any one of said cutting edges (13, 13' ; 25, 25') is arranged such on the roller (11, 11') that the resulting plasterboard-pieces have a side length of between 2 to 35 cm, preferably 5 to 20 cm and more preferably around 10 to 15 cm.
     
    13. The cutting device (10) according to any one of the preceding claims 7-12, wherein any one of said cutting edges (13, 13'; 25, 25') has a height of 2-10 mm and preferably 3-6 mm.
     
    14. The cutting device (10) according to any one of the preceding claims 7-13, wherein any one of said cutting edges (13, 13'; 25, 25') is tooth-shaped.
     


    Ansprüche

    1. Verfahren zum Schneiden von gipshaltigem Material, vorzugsweise Gipskartonplatten (1), wobei das Verfahren folgende Schritte umfasst:

    Hineinführen von Gipskartonplatten (1) in eine Schneidvorrichtung (10), wobei die Schneidvorrichtung (10) mindestens eine Walze (11) umfasst, um die herum voneinander beabstandete Schneidkanten (13) angeordnet sind,
    wobei das Verfahren des Weiteren den Schritt umfasst, mindestens einen Schneidvorgang an der Gipskartonplatte (1) in einer Längsrichtung und einer im Wesentlichen quer verlaufenden Richtung in Bezug auf eine Zufuhrrichtung auszuführen, wobei das Verfahren dadurch gekennzeichnet ist, dass der im Wesentlichen in der Querrichtung verlaufende Schnitt mit einer spiralförmig verlaufenden Schneidkante (25), die um die mindestens eine Walze (11) herum verläuft, während der Drehung der Walze (11) bewerkstelligt wird und dass die Walzen, unter Spannung stehend, in Bezug aufeinander beweglich sind, dergestalt, dass Gipskartonplatten von unterschiedlichen Dicken geschnitten werden können.


     
    2. Verfahren nach Anspruch 1, wobei die Gipskartonplatte (1) geschnitten wird, wenn sie zwischen zwei komplementär angeordnete spiralförmige Schneidkanten (25, 25'), die an einer jeweiligen Walze (11, 11') vorhanden sind, eingeführt wird.
     
    3. Verfahren nach einem der vorangehenden Ansprüche, wobei die Umfangsgeschwindigkeiten der komplementären spiralförmigen Schneidkanten (25; 25') während des Schneidens gleich sind, so dass die jeweiligen Teile der spiralförmigen Schneidkanten (25, 25') einander zugewandt sind, wenn sie sich in ihrer nahesten Position in Bezug aufeinander befinden.
     
    4. Verfahren nach einem der vorangehenden Ansprüche, wobei die Walzen (11, 11') durch schwenkbare Halterelemente (16, 16') gehalten werden.
     
    5. Verfahren nach einem der vorangehenden Ansprüche, wobei der Schneidvorgang durch eine motorgetriebene Schneidvorrichtung (10) ausgeführt wird.
     
    6. Verfahren nach einem der vorangehenden Ansprüche, wobei die entstehenden Gipskartonstücke (2) in einem Recycling-Behälter (3) aufgefangen werden.
     
    7. Schneidvorrichtung (10) zum Schneiden von gipshaltigem Material, vorzugsweise Gipskartonplatten (1), wobei die Schneidvorrichtung (10) einen Einlass (15) für die Gipskartonplatten (1) und mindestens eine Walze (11) umfasst, wobei die Schneidvorrichtung (10) Schneidkanten zum Ausführen mindestens eines Schneidvorgangs an der Gipskartonplatte (1) in einer Längsrichtung und einer im Wesentlichen quer verlaufenden Richtung in Bezug auf eine Zufuhrrichtung der Gipskartonplatte umfasst, wobei die Schneidvorrichtung (10) eine spiralförmige Schneidkante (25) umfasst, die um die mindestens eine Walze (11) herum angeordnet ist, dadurch gekennzeichnet, dass die Walzen (11, 11'), unter Spannung stehend, in Bezug aufeinander beweglich sind, dergestalt, dass Gipskartonplatten (1) von unterschiedlichen Dicken geschnitten werden können.
     
    8. Schneidvorrichtung (10) nach Anspruch 7, wobei komplementär angeordnete spiralförmige Schneidkanten (25, 25') an einer jeweiligen Walze (11, 11') vorhanden sind, dergestalt, dass die Gipskartonplatte

    (1) geschnitten wird, wenn sie zwischen zwei komplementär angeordnete spiralförmige Schneidkanten (25, 25'), die an einer jeweiligen Walze (11, 11') angeordnet sind, angeführt wird.


     
    9. Schneidvorrichtung (10) nach einem der vorangehenden Ansprüche 7-8, wobei die Umfangsgeschwindigkeiten der komplementären spiralförmigen Schneidkanten (25; 25') während des Schneidens gleich sind, so dass die jeweiligen Teile der spiralförmigen Schneidkanten (25, 25') einander zugewandt sind, wenn sie sich in ihrer nahesten Position befinden.
     
    10. Schneidvorrichtung (10) nach einem der vorangehenden Ansprüche 7-9, wobei die Walzen (11, 11') durch schwenkbare Halterelemente (16, 16') gehalten werden.
     
    11. Schneidvorrichtung (10) nach einem der vorangehenden Ansprüche 7-10, wobei die Schneidvorrichtung (10) motorgetrieben ist.
     
    12. Schneidvorrichtung (10) nach einem der vorangehenden Ansprüche 7-11, wobei jede der Schneidkanten (13, 13'; 25, 25') so an der Walze (11, 11') angeordnet ist, dass die entstehenden Gipskartonstücke eine Seitenlänge zwischen 2 und 35 cm, bevorzugt 5 und 20 cm und besonders bevorzugt etwa 10 und 15 cm aufweisen.
     
    13. Schneidvorrichtung (10) nach einem der vorangehenden Ansprüche 7-12, wobei jede der Schneidkanten (13, 13'; 25, 25') eine Höhe von 2-10 mm und bevorzugt 3-6 mm aufweist.
     
    14. Schneidvorrichtung (10) nach einem der vorangehenden Ansprüche 7-13, wobei jede der Schneidkanten (13, 13'; 25, 25') zahnförmig ist.
     


    Revendications

    1. Procédé pour la coupe de matériaux comprenant du gypse, de préférence des plaques de plâtre (1),
    ledit procédé comprenant les étapes consistant à :

    alimenter lesdites plaques de plâtre (1) dans un dispositif de coupe (10), ledit dispositif de coupe (10) comprenant au moins un rouleau (11) autour duquel des bords de coupe (13) espacés l'un de l'autre sont prévus,

    ledit procédé comprend en outre l'étape consistant à effectuer au moins une opération de coupe de ladite plaque de plâtre (1) dans une direction longitudinale et une direction essentiellement transversale par rapport à une direction d'alimentation, ledit procédé étant caractérisé en ce que ladite coupe essentiellement transversale peut être accomplie, avec un bord de coupe spiral (25) prévu autour dudit au moins un rouleau (11) pendant la rotation dudit rouleau (11), et en ce que les rouleaux sont déplaçables d'une manière l'un par rapport à l'autre telle que des plaques de plâtre d'épaisseurs différentes puissent être coupées.


     
    2. Procédé selon la revendication 1, dans lequel ladite plaque de plâtre (1) est coupée quand elle est introduite entre deux bords de coupe (25,25') spiraux agencés complémentairement prévus sur un rouleau respectif (11,11').
     
    3. Procédé selon une quelconque des revendications précédentes, dans lequel les vitesses périphériques des bords de coupe spiraux complémentaires (25 ;25') sont égales pendant la coupe de sorte que la partie respective des bords de coupe spiraux (25,25') fasse face à une autre quand ils sont dans leur position la plus proche l'un par rapport à l'autre.
     
    4. Procédé selon une quelconque des revendications précédentes, dans lequel les rouleaux (11,11') sont maintenus par des éléments de support pivotants (16,16').
     
    5. Procédé selon une quelconque des revendications précédentes, dans lequel l'opération de coupe est effectuée par un dispositif de coupe motorisé (10).
     
    6. Procédé selon une quelconque des revendications précédentes, dans lequel les pièces de plaques de plâtre (2) de résultat sont collectées dans un conteneur de recyclage (3).
     
    7. Dispositif de coupe (10) pour la coupe de matériaux comprenant du gypse, de préférence des plaques de plâtre (1), ledit dispositif de coupe (10) comprenant une admission (15) pour lesdites plaques de plâtre (1) et au moins un rouleau (11), ledit dispositif de coupe (10) comprend des bords de coupe pour effectuer au moins une opération de coupe de ladite plaque de plâtre (1) dans une direction longitudinale et essentiellement transversale par rapport à une direction d'alimentation de la plaque de plâtre, ledit dispositif de coupe (10) comprend un bord de coupe spiral (25) prévu autour dudit au moins un rouleau (11), caractérisé en ce que les rouleaux sont déplaçables d'une manière l'un par rapport à l'autre telle que des plaques de plâtre d'épaisseurs différentes puissent être coupées.
     
    8. Dispositif de coupe (10) selon la revendication 7, dans lequel des bords de coupe spiraux (25,25') agencés complémentairement sont prévus sur un rouleau respectif (11,11') de sorte que ladite plaque de plâtre (1) soit coupée quand elle est introduite entre deux bords de coupe spiraux (25,25') agencés complémentairement prévus sur un rouleau respectif (11,11').
     
    9. Dispositif de coupe (10) selon une quelconque des revendications précédentes 7 à 8, dans lequel les vitesses périphériques des bords de coupe spiraux complémentaires (25 ;25') sont égales pendant la coupe de sorte que la partie respective des bords de coupe spiraux (25,25') fasse face à une autre quand ils sont dans leur position la plus proche l'un par rapport à l'autre.
     
    10. Dispositif de coupe (10) selon une quelconque des revendications précédentes 7 à 9, dans lequel les rouleaux (11,11') sont maintenus par des éléments de support pivotants (16,16').
     
    11. Dispositif de coupe (10) selon une quelconque des revendications précédentes 7 à 10, dans lequel ledit dispositif de coupe (10) est motorisé.
     
    12. Dispositif de coupe (10) selon une quelconque des revendications précédentes 7 à 11, dans lequel n'importe lequel desdits bords de coupe (13,13' ;25,25') est agencé de sorte sur le rouleau (11,11') que les pièces de plaques de plâtre de résultat aient une longueur latérale comprise entre 2 et 35 cm, de préférence entre 5 et 20 cm et de manière encore préférée entre environ 10 et 15 cm.
     
    13. Dispositif de coupe (10) selon une quelconque des revendications précédentes 7 à 12, dans lequel n'importe lequel desdits bords de coupe (13,13' ;25,25') a une hauteur de 2 à 10 mm et de préférence 3 à 6 mm.
     
    14. Dispositif de coupe (10) selon une quelconque des revendications précédentes 7 à 13, dans lequel n'importe lequel desdits bords de coupe (13,13' ;25,25') est en forme de dents.
     




    Drawing














    Cited references

    REFERENCES CITED IN THE DESCRIPTION



    This list of references cited by the applicant is for the reader's convenience only. It does not form part of the European patent document. Even though great care has been taken in compiling the references, errors or omissions cannot be excluded and the EPO disclaims all liability in this regard.

    Patent documents cited in the description