FR2555637A1 - Method for injecting and expanding an insulating material in a construction element and machine for the implementation of this method - Google Patents

Abstract

The present invention relates to a method and a device for injecting and expanding an insulating material in a construction element. The machine for the implementation of the method comprises a frame 11 carrying a worktable 15 consisting of the lower part 12 of a mould, the upper part 14 of which can move vertically. This upper part 14 is carried by a carriage 18 capable of sliding vertically on columns 13 by means of a hydraulic or pneumatic jack 19. The upper part 14 of the mould comprises an expansible peripheral tie 21 intended to exert, on the external walls of a construction element 16, a predetermined pressure which is sufficient to compensate for the internal pressures exerted on this element during the phase of expansion of the insulating material. This method and this machine are intended in particular for producing insulating bricks which can be used for building a vertical isothermal masonry construction.

Description

METHOD FOR INJECTING AND EXPANDING AN INSULATING MATERIAL IN AN ELEMENT
CONSTRUCTION METHOD AND MACHINE FOR IMPLEMENTING THIS METHOD.
The present invention relates to a method for injecting and expanding an insulating material into a building element comprising an outer wall and an inner wall separated by connecting partitions connecting the two walls together and defining at least one cell intended to contain said insulating material .

It also relates to a machine for implementing this method.

Various methods are already known for carrying out the installation of an insulating material inside a prefabricated or molded construction element. Generally the insulating material designed in the form of a block or a plate is produced in the factory and attached to the construction element, this operation can be carried out in the factory or in the field. However, there is also known a process consisting in injecting and expanding a loose insulating material, in particular pre-expanded polystyrene6, which is injected into the space separating two plates of a rigid material, for example of prestressed concrete, and which is intended to ensure the lateral connection between the two plates.

However, it is not. little known to make a terracotta brick and a slab in the cells of which one injects and expands directly an insulating material such as pre-expanded polystyrene. Bricks with vertical perforations and thin walls are generally not strong enough to withstand the stresses which they must undergo at the time of the injection of the insulating material and especially during the expansion of the latter.
The present invention proposes to overcome this drawback and to fill this gap by proposing a method as mentioned above, characterized in that said building element is introduced into a mold, in that it surrounds said element. of an expandable belt, in that one expands said belt to exert on said walls of building element a determined pressure #, in that one injects the insulating material in said mold and in particular inside said cell, in that one expands this insulating material, in that one returns said expandable belt in its initial state and in that one extracts said construction element from said mold.

According to a preferred embodiment, said belt comprises at least one inflatable hose and preferably compressed air is injected into this hose at a pressure sufficient to compensate for the pressures exerted on the interior surfaces of the walls of the element of construction during the expansion phase of the insulating material.

This method is particularly applicable to the production of a brick comprising a protective outer wall provided with multiple vertical perforations separated by a network of fine partitions, a second load-bearing interior wall, also provided with a network of fine partitions and partitions. connecting connecting said first wall to said second wall by defining several cells whose cross section is substantially larger than that of said vertical perforations, these cells crossing the brick right through. According to a particularly advantageous embodiment, the brick is introduced into a mold designed so that the insulating material injected and expanded in this mold forms a unitary block composed of interior elements filling said cells, an exterior element resting on one of the exterior sides of the brick and a plate connecting the elements inside and outside, this plate having a thickness substantially equal to the thickness of the layer of mortar separating two superimposed rows of bricks.

The insulating material which is injected into the mold preferably comprises expanded polystyrene beads and the expansion cycle of these beads is completed using heated water vapor.

The machine according to the invention is characterized in that it comprises a work table and transfer members for bringing the raw construction elements onto the work table, a removable mold and means for placing this mold in position around said construction element, an expandable belt housed inside the mold and means for causing the expansion of this belt in order to exe # - cer on the walls of the construction element a determined pressure, means for injecting the insulating material in bulk in the mold and means for causing its expansion, members for removing the mold and means for evacuating the building elements at the end of this process.

According to a preferred embodiment, the mold consists of a fixed lower part comprising said work table onto which the raw construction elements are transferred and a movable part on the top containing said expandable belt.

This expandable belt advantageously comprises at least one hose connected to a source of compressed air. This hose is preferably constituted by a textile structure having a high resistance and which is sealed by an inner coating of an elastomer and resistant to high temperatures.

The present invention and its main advantages will be better understood with reference to the description of an exemplary embodiment and the attached drawing in which
FIG. 1 represents a schematic elevation view of the machine according to the invention, and
FIG. 2 represents a view in horizontal section through the upper part of the mold during the process of injection and expansion of the insulating material.

With reference to FIG. 1, the machine 10 described below essentially consists of a chassis, the lower part 11 of which carries on the one hand the fixed lower part 12 of the mold and on the other hand a column structure 13 which carries the movable upper part 14 of the mold. The upper surface of the fixed part 12 of the mold constitutes a work table 15 on which the building elements 16 are brought, such as for example a brick with vertical perforations and with cells which are intended to receive an insulating material or slabs or any other similar material. The construction elements 16 can be positioned manually or brought in by an automatic transfer system such as for example a roller guide 17, a conveyor belt, etc.

The movable upper part 14 of the mold is mounted on a carriage 18 capable of moving vertically along the columns 13 under the action of a hydraulic or pneumatic cylinder 19, the body of which is carried by a cross member 20 fixed between the upper ends of the columns 13.

The interior of the upper part 14 of the mold is preferably lined on at least its two large lateral surfaces with an expandable belt 21, preferably consisting of at least one inflatable hose connected to a source of compressed air (not shown) . The inflatable belt preferably consists of segments of pipes formed by a particularly resistant textile structure sealed by an inner coating of an elastomer resistant to high temperatures. It can be carried out using a single section lining three walls or the four interior walls of the upper part 14 of the mold or in several separate sections and possibly supplied independently. The purpose of this expandable belt is to allow to exert on the outer walls of the building element a pressure intended to compensate for the pressure exerted on the inner walls of the building element at the time of injection and expansion of the insulating material.

A tank 22 containing a reserve of raw materials is mounted on the cross-member 20. Two flexible pipes 23 connecting the tank 22 to two tubular elements 24 carrying injection nozzles (not shown) make it possible to inject the polystyrene beads pre-expanded to the inside the mold.

Since the expansion of the pre-expanded polystyrene beads is carried out using superheated steam, the machine is preferably connected by a conduit 25 to a steam generator (not shown). The compressed air supply used both to inject the pre-expanded polystyrene beads and to inflate the expandable belt, is schematically represented by line 26.

FIG. 2 represents a view in section through the upper part 14 of the mold containing a building element 16. In this case, the building element is constituted by a brick intended for the realization of a vertical isothermal masonry construction, and comprising a first protective external wall 30 provided with multiple vertical perforations 31 separated by a network of fine partitions 32. It also comprises a second bearing internal wall 33 also provided with vertical perforations 34 separated by a network of fine partitions 35. The protective external wall and the load-bearing interior wall are separated by connecting partitions 36 defining cells 37. The mold 14 is designed in such a way that a unitary block of expanded polystyrene forms, filling both the cells 37, forming a localized vertical band. in the lateral recess 38 of the brick and a horizontal strip connecting the upper surface of this vertical strip and blocks housed in the cells 37. To avoid breaking the relatively fragile side walls of the brick, the mold, or at least its upper part 14 is lined on at least three sides of the inflatable belt 21 which can be produced in one piece or in three sections supplied with compressed air by one or more supplies 39.

 It is understood that the mold must be adapted to the shape of the building element to be treated. For this purpose, the upper part of the mold is interchangeable to present a structure adapted to the shape and dimensions of the building element.

Although this machine has been described with reference to a drawing illustrating a particular embodiment, it is not limited to this embodiment but can undergo different modifications and come in various variants obvious to those skilled in the art .

Claims (9)

Claims 1. Method for injecting and expanding an insulating material into a building element comprising an outer wall and an inner wall separated by connecting partitions connecting the two walls together and defining at least one cell intended to contain said insulating material, characterized in that one introduces said construction element (16) into a mold (12, 14), in that one surrounds said element with an expandable belt (21), in that one expands said belt to exert on said construction walls a determined pressure, in that the insulating material is injected into said mold and in particular inside said cell, in that this insulating material is expanded, in that one returns said expandable belt to its initial state and in that said construction element is extracted from said mold. 2. Method according to claim 1, characterized in that said belt (21) comprises at least one inflatable hose, and in that one injects into this hose compressed air at a pressure sufficient to compensate for the pressure exerted on 1at inner surface of the walls of the building element (16) at the time of the expansion phase of the insulating material. 3. Method according to la.revendication 1, wherein the building element (16) is a brick having a protective outer wall (30) provided with vertical perforations (31) separated by a network of fine partitions (32), a second load-bearing inner wall (33) also provided with vertical perforations (34) separated by a network of. vertical partitions (35), and connecting partitions (36) connecting the. said first wall to said second wall by defining several cells (37) whose section is substantially larger than those of said vertical perforations, these cells passing through the brick right through, characterized in that the brick is introduced into a mold (12, 14) designed so that the insulating material injected and expanded in this mold forms a unitary block composed of interior elements filling said cells, an exterior element resting on one of the exterior sides of the brick and a plate connecting the interior elements and the exterior element, this plate having a thickness substantially equal to the thickness of the layer of mortar separating two superimposed rows of bricks. 4. Method according to claim 1, characterized in that the insulating material which is injected into the mold comprises pre-expanded polystyrene beads and in that the expansion cycle of these beads is completed using superheated steam. 5. Machine for injecting and expanding a thermally insulating material into a construction element comprising an outer wall and an inner wall separated by connecting partitions connecting the two walls together and defining at least one cell intended to contain said thermally insulating material, characterized in that it comprises a work table (15) and transfer members (17) for bringing the construction elements to the work table, a removable mold part (14) and means for placing this mold in position around said building element (16), an expandable belt (21) housed inside the mold and means for causing the expansion of this belt to exert on the walls of the building element a determined pressure, means (24) for injecting the loose insulating material into the mold and means (25) for causing its expansion, members (19) for removing the mold and means for removing the The building blocks at the end of this process.  6. Machine according to claim 5, characterized in that the mold consists of a lower fixed part (12) comprising said work table (15) on which the building elements are transferred, and an upper movable part (14) containing said expandable belt (21). 7. Machine according to claim 6, characterized in that said expandable belt (21) comprises at least one hose connected to a source of compressed air. 8. Machine according to claim 7, characterized in that the hose is constituted by a textile structure having a high resistance, and sealed by an inner coating of an elastomer resistant to high temperatures. 9. Machine according to claim 8, characterized in that the belt consists of several sections supplied independently with compressed air.