Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B28—WORKING CEMENT, CLAY, OR STONE
  • B28B—SHAPING CLAY OR OTHER CERAMIC COMPOSITIONS; SHAPING SLAG; SHAPING MIXTURES CONTAINING CEMENTITIOUS MATERIAL, e.g. PLASTER
  • B28B19/00—Machines or methods for applying the material to surfaces to form a permanent layer thereon
  • B28B19/0092—Machines or methods for applying the material to surfaces to form a permanent layer thereon to webs, sheets or the like, e.g. of paper, cardboard

Definitions

• the present invention relates to a method of manufacturing plates based on hydraulic binder such as plaster, these plates having thinned edges.
• the invention also relates to a production line for such plates and to a device that can be used to manufacture these plates.
• the solution proposed by the first of these patents consists in making a transverse groove in the lower sheet of paper by folding the latter before pouring the plaster composition and arriving on the conveyor belt.
• the transverse groove protruding from the bottom sheet of paper creates, after the sheet of paper on the conveyor belt, a hollow whose walls are oblique.
• By then cutting the plate at the end of each part at an angle two plates with thinned transverse edges are obtained.
• Such a solution is difficult to implement because it requires the installation of special rollers for the production of the groove.
• the plate must be cut in two places, which has the further disadvantage of producing a large amount of waste.
• the invention therefore aims to provide a method for manufacturing plasterboard having thinned transverse edges. This process manages to remedy the drawbacks of the techniques proposed in the prior art.
• the invention relates to a method of manufacturing a plate based on hydraulic binder, with thinned edges, in which: 1) a hydraulic binder composition is poured over a facing material supported by a conveyor belt, so as to obtain a preform,
• a slat whose length is at least approximately equal to the width of the preform is introduced under the preform;
• step 2) said slat is removed; and in that b) the cutting of step 3) is carried out at the level of the thinning created by the slat.
• the invention also relates to a production line for plates based on hydraulic binder having thinned edges from a preform comprising a facing material covered with a hydraulic binder composition, this production line comprising a conveyor belt as well as, near this conveyor belt, means for introducing, between the preform and the conveyor belt, a slat whose length is at least approximately equal to the width of the preform.
• the invention also provides a device for the introduction of slats on a conveyor belt with a view, in particular, to manufacturing plates based on hydraulic binder having thinned edges, this device comprising:
• FIG. 3 shows a plate as obtained by the method according to the invention
• FIG. 4 shows a plate obtained by the method according to the preferred embodiment of the invention.
• FIG. 7 shows schematically and in top view, the device according to the invention.
• FIG. 10 shows schematically and in section, a detail of the device according to the invention illustrating one introduction of the slat under the plate based on hydraulic binder, during training.
• transverse edges is meant in the present description the edges perpendicular to the direction of movement of the conveyor belt in a production line for sheets based on hydraulic binder.
• a production line of plates produced by casting on a facing material 1 of a hydraulic binder composition 2 and covering with a second facing material 3. The passage of one set under the forming plate 4 gives a preform 5.
• the hydraulic binder composition preferably includes plaster.
• the facing materials 1 and 3 may consist of sheets of paper or cardboard, glass mats or any material known to those skilled in the art as being able to serve as facing material.
• a batten 6 is introduced between the preform 5 and the start of the conveyor belt 7.
• the distance between the forming plate 4 and the start of the conveyor belt 7 is such that the preform 5 has not yet had time to harden substantially and is still present great plasticity.
• the introduction is carried out in such a way that the longitudinal axis of the slat 6 is substantially perpendicular to the direction of movement of the conveyor belt 7.
• the slat 6 is then driven by the conveyor belt 7, just like the preform 5.
• the hydraulic setting and hardening of the plaster composition 2 is then carried out throughout the movement of the preform 5, designated by the arrows A.
• the slat 6 is removed before the preform 5 is cut.
• the hardness of the preform 5 is sufficient so that the slat 6 can be removed without deforming the preform 5 and without the plaster composition 2 come fill the space or thinning 8 ( Figure 2) left by the removal of the slat 6.
• the removal of the slat 6 can be carried out in any suitable manner. For example, when the length of the slat 6 is greater than the width of the preform 5, the slat 6 protrudes relative to the preform 5, and it can then be removed quickly in a direction substantially perpendicular to the direction of movement of the conveyor belt 7 and away from it. This withdrawal action is illustrated by the arrow B.
• the withdrawal of the batten 6 can also occur by the fall of this batten 6 in the space situated between two rollers constituting the system of conveyor belts which, in general, is not continuous throughout the production line, but is formed by several mats driven by rollers between which there are free spaces.
• the preform 5 continues to move, still driven by the conveyor belt 7 and the hardening of the plaster composition 2 continues.
• the thinning 8 arrives at the height of the cutting device generally constituted by a roller provided with a knife 9, the latter starts up and cuts the preform 5.
• This plate 9 therefore has two thinned transverse edges 10.
• the cutting device is adjusted so that the knife 9 cuts the preform 5 approximately in the middle of the thinning operation 8.
• each thinning 8 depends on the dimensions of the slat 6.
• the latter is generally a parallelepiped whose thickness is generally between 0.5 and 4 mm, preferably between 1.5 and 4 mm. Its width is generally between 5 and 20 cm and its length is at least approximately equal to the width of the preform 5 (possibly reduced by the width of the longitudinal “tape” bands present if necessary), but in general greater in order to be able to grasp it to remove it from beneath the preform 5.
• the slat 6 be of a length greater than the width of the preform 5, so as to project from it, which can facilitate its removal.
• the material of the slats 6 does not matter, as long as it allows these slats to resist the weight of the thickness of preform 5 which is located above each slat 6. It can therefore be a plastic material, wood , metal, paper, cardboard, etc. with good wear resistance and stability over time.
• the slats can be obtained by cutting from a continuous strip from a roll.
• the method which has just been described complements a known method for manufacturing plasterboards having two thinned longitudinal edges.
• the latter generally provides for the installation of a strip, generally made of plastic, generally called a "tape", on each longitudinal side of the conveyor belt 7.
• a strip generally made of plastic, generally called a "tape”
• Such a process is described for example in European patent application No. 482,810 This therefore makes it possible to obtain a plate based on hydraulic binder 11 as illustrated in FIG. 4, having, in addition to its two thinned transverse edges 10, two longitudinal thinned edges 25, ie in total four thinned edges.
• the length of the plasterboard produced depends, of course, on the speed of movement of the conveyor belt and the frequency of the cutting operations.
• the frequency of cutting operations is generally directly related to the frequency of insertion of the slats, because it is generally sought to obtain plates having two thinned transverse edges.
• the method according to the invention is very flexible, because to change the length of the plates produced, it suffices simply to modify the frequency of introduction of the slats.
• the method according to the invention further comprises an intermediate step in which an impression 12 of the preform 5 is produced opposite the place where it is planned to introduce the batten 6 and / or an imprint 12bis at the place where it is planned to introduce batten 6.
• the 12 or 12bis impression can be made by any means, for example, by following the teachings of American patents No. 2,991,824 or 4,781,558.
• the conveyor belt 7 may possibly have been sanded and / or waxed, for example using a mineral oil.
• JP 53051227 proposes to coat a conveyor belt using a silicone mineral oil.
• FIG. 6 shows a part of a production line for plates based on hydraulic binder implementing the method according to the invention.
• a slatted magazine 20 formed of a horizontal rectangular surface 21 from the corners of which rise vertically and in parallel, four angular pieces 22, in the form of angle iron and turned towards each other, so as to frame a stack of slats 23.
• the dimensions of this slat magazine 20 are such that it can store a large number of slats 23 (see also Figures 7 and 8).
• the horizontal surface 21 of the slat magazine 20 is supported by feet 24.
• two cylinders 26 are arranged in parallel, which are oriented so as to extract the first batten 23 from the stack by pushing and sliding it to an inclined plane 27 consisting of a downwardly inclined surface 28 and a flange 29 at its lower part to retain the slat which has just been extracted and guide it later.
• a cylinder 31 is arranged parallel to the longitudinal axis of the inclined plane 27, so that the actuation of this jack 31 can give an impetus to the slat which has just been extracted from the slat magazine 20.
• the slat thus propelled can then move by sliding parallel to the longitudinal axis of the inclined plane 27, the flange 29 of which guides it , towards a second inclined plane 32 which extends the first inclined plane 27, on the transverse side opposite to the side 30.
• This second inclined plane 32 also consists of an inclined surface 33 provided with a flange 34 at its lower part.
• a stop 35 at its end opposite to the jack 31, this stop being generally made up of a pneumatic shock absorber and being intended to stop the movement of the slat propelled by the jack 31.
• the flange 34 is provided with openings 36 in front of which are arranged two jacks 37 oriented so as to propel the batten positioned on the second inclined plane 32 upwards of the inclined surface 33.
• the first inclined plane 27 and the second inclined plane 32 are supported by feet, respectively, 38 and 39.
• a flat surface 40 is provided parallel to the surface 23, between this last and the first inclined plane 27 for horizontally supporting a slat extracted from the slat magazine 20 before its descent on the inclined surface 28 of the first inclined plane 27.
• the height of the feet 24, 35 and 36 is chosen such that a slat positioned on the second inclined plane 32 is situated at a height less than that of the preform 5.
• the longitudinal axis of the flange 34 of the second inclined plane 32 is perpendicular to the longitudinal axis of the conveyor belt; - The means 32, 33, 34, 35 for supporting the displaced batten are located opposite the start of the conveyor belt 7; and the inclined surface 33 of the second inclined plane 32 is adjacent to the conveyor belt 7.
• the length of the second inclined plane 32 is at least equal to that of the slat 23, that is to say at least equal, and preferably greater than the width of the preform 5.
• the difference between the length of the slat and the width of the preform 5 makes it possible to grip the slat and remove it once the plaster composition has hardened.
• the production line according to the invention generally comprises electronic means which control its operation and make it possible, if necessary, to control between them the implementations of different operations.
• the production line further comprises a device making an imprint 12.
• the electronic means controlling the production line according to the invention are then adjusted with the electronic means controlling the device making the impression 12, so that each slat is introduced under the plate based on hydraulic binder on the side of the preform 5 opposite the place where an impression 12 is located, as can be see it in figure 10.

Landscapes

• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Ceramic Engineering (AREA)
• Mechanical Engineering (AREA)
• Dry Formation Of Fiberboard And The Like (AREA)

Priority Applications (1)

Applications Claiming Priority (4)

Publications (1)

Family

ID=8184774

Family Applications (2)

Family Applications Before (1)

Country Status (2)

Families Citing this family (1)

Family Cites Families (3)

• 2001
  • 2001-11-16 EP EP01830706A patent/EP1321261A1/de not_active Withdrawn
• 2002
  • 2002-11-15 WO PCT/FR2002/003919 patent/WO2003041930A1/fr not_active Application Discontinuation
  • 2002-11-15 EP EP02791903A patent/EP1448347A1/de not_active Withdrawn

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events