EP0272559B1 - Process for stripping an adhesive cover, and device for carrying out the process - Google Patents

Abstract

PCT No. PCT/EP87/00772 Sec. 371 Date Aug. 19, 1988 Sec. 102(e) Date Aug. 19, 1988 PCT Filed Dec. 11, 1987 PCT Pub. No. WO88/04617 PCT Pub. Date Jun. 30, 1988.Heavy wall, ceiling and floor coverings with closed surfaces can be pulled or pushed off relatively easily if the material connecting the coating with the substrate in an adhesive joint can at least be loosened with the aid of a stripping fluid. In accordance with the invention, a stripping fluid is pressed in an air-free, pulse-like way with the aid of a needle nozzle (1) through the coating with a high pressure into the adhesive joint (FIG. 1).

Description

The invention is directed to a method for detaching a covering which has a closed surface and is glued to a substrate with the aid of a detaching liquid which emerges airlessly from nozzles under high pressure. Furthermore, the invention is directed to a device with nozzles which release air-free release liquid under high pressure for removing a covering which has a closed surface and is bonded to a substrate.

Glued coverings with a closed surface, such as wall, ceiling or floor coverings, can only be removed with difficulty, especially in the case of heavy versions. The group of these coverings includes wallpaper-like wall coverings consisting of PVC foam plastic; PVC films with fabric backing; plucking, jute and glass fiber fabrics coated with silicate paints or emulsion paints or lacquer paints; Woodchip with multiple coats of emulsion paint; Elephant skin-protected wallpaper and ceiling panels made of foamed polystyrene. Such coverings can be removed by steam jet devices, by planing, with the aid of a spatula and manual repulsion by the centimeter, by pretreating the cover with a nail roller and / or by wetting with a wallpaper stripper. Exposed adhesive residues can also be softened and removed by brushing with a paint remover.

Removing glued carpets is also particularly difficult. New floors are removed by wetting and tearing out, by cutting into strips and tearing out the individual strips or by flat cutting or filing and sanding off the remains. All of the detachment processes used in the past are extremely labor-intensive, time-consuming and involve considerable amounts of dirt.

A method of the type mentioned is known from DE-B-25 52 611. In this method, the covering to be detached is mechanically destroyed in some areas, for example cut into strips, by means of a device which has flat jet nozzles and from which the detaching liquid is dispensed. These individual areas, for example the strips, of the covering are then easier to remove than the entire covering. It can also be provided that the working fluid jet already lifts the covering to be removed. This way of working is labor-intensive, time-consuming and in particular accompanied by a considerable amount of dirt.

The invention has for its object to provide a method and an apparatus which make it possible to soften or detach the connection means between the covering and the subsurface in the present context, for the sake of simplicity, even in the case of a heavy covering with a closed surface, in such a way that the covering can be removed by pulling off or pushing off with the help of a spatula.

In a method of the type described in the introduction, this object is achieved according to the invention in that the release liquid is injected in pulses with the aid of at least one needle nozzle through the covering into the adhesive joint between the covering and the substrate.

This makes it possible for the adhesive located in the space between the covering and the substrate to be dissolved or chemically decomposed before the covering is mechanically separated or lifted off. This first destroys the adhesive bond between the covering and the surface, and then the covering can be removed easily and simply by simply pulling it off the surface. A solution is thus created which enables the release agent to get onto the back of the covering.

By the invention it is achieved that the adhesive located in the adhesive joint between the covering and the substrate is to be softened or dissolved or chemically decomposed before the mechanical separation of the covering, because the pure, airless release liquid is under sufficient pressure to penetrate the covering, e.g. B.
under 100 to 400 bar, is pressed directly into the adhesive joint. Airless piston or diaphragm pumps can be used to pump the release liquid at high pressure. The depth of penetration of the release liquid is therefore adjusted by changing the pressure at the inlet of the nozzle. The process is particularly effective with a slightly viscous release liquid, which improves the removal of the covering from the surface (wedge effect).

In a device of the type mentioned, the object is achieved according to the invention in that it injects at least one detaching liquid into the adhesive joint between the substrate and the covering with a needle-like valve by pressing the needle nozzle against the covering to be detached with a pressure line of the detaching liquid, in particular a nozzle opening about 0.3 mm in diameter, which is surrounded by a concave hollow shell to be placed on the covering.

The result of the hollow shell is that the release liquid possibly present at the nozzle opening with high pressure can also be pressed through a dense and heavy covering. A cutting ring, an O-ring, in particular made of rubber, or a flat gasket is expediently used to seal the hollow shell.

A practical design of the device for pressing the release liquid into the adhesive joint between the covering and the substrate is created when the needle nozzle at the end of a cavity that is movably guided in a cylinder against a spring force possessing nozzle piston and the cavity has a cross hole to be switched by pressing the nozzle piston against the spring force on the pressure line of the release liquid. This nozzle piston is to be guided with a precise fit, for example in a slotted cylinder, in order on the one hand to exactly meet the connection of the piston to the pressure line of the release liquid and on the other hand to prevent squeezing out of release liquid through the piston / cylinder seal.

The movable nozzle is pressed into the cylinder by pressing such a device onto the surface carrying the covering to be removed. The cross sections of the connection between the piston cavity and the pressure line of the release liquid opening into the cylinder are covered and the release liquid shoots into the coating with high pressure. As a result, a recoil is exerted on the device, which pushes the device away from the wall, so that the piston is pushed out of the cylinder again by the spring force acting on it and thus the liquid supply is interrupted. The device is immediately ready for the next injection.

In the case of a device according to the invention to be guided by hand, two or more needle nozzles can also be arranged linearly or areally on a carrier element designed as a hollow body connected to a pressure line of the release liquid. The operator only needs to apply the force necessary to guide the device and to push the nozzle (open the nozzle against a spring). In contrast, the force required to press the release liquid into the adhesive joint is supplied by the connected pump due to the high liquid pressure.

The carrier element carrying one or more needle nozzles can also be resiliently suspended as a larger machine in a roller box, wherein a mechanism, in particular cam mechanism, which periodically lowers the carrier element when the box is advanced, is provided and controlled by the roller. The suspension of the carrier element should be adjusted so that it pulls the carrier element upwards into the roller box in the rest position. The wheels are to be coupled to the lowering mechanism of the carrier element in such a way that when the roller box is pushed, the carrier element is periodically lowered in such a way that the nozzles are pressed abruptly against the covering. The associated pressing of the nozzles on the substrate triggers an injection of detachment liquid.

• Fig. 1 eine Prinzipskizze der Düse und deren Lagerung;
• Fig. 2 einen Schnitt durch ein mit der Hand zu führendes Injektionsgerät für Ablöseflüssigkeit;
• Fig. 3 einen Schnitt durch eine über den Boden zu schiebende Vorrichtung zum Einpressen von Ablöseflüssigkeit in die Klebefuge zwischen einem Bodenbelag und dem Untergrund.

Details of the invention are explained on the basis of the schematic representation of exemplary embodiments. Show it

• Figure 1 is a schematic diagram of the nozzle and its storage.
• FIG. 2 shows a section through an injection device for detachment liquid which is to be guided by hand;
• Fig. 3 shows a section through a device to be pushed over the floor for pressing release liquid into the adhesive joint between a floor covering and the substrate.

The needle nozzle denoted overall by 1 in FIG. 1 is designed as a movable hollow nozzle piston 2 with a cavity 4 leading to the nozzle opening 3. The cavity 4 has a transverse bore 5 which, when the nozzle is moved in the direction of the arrow 6, is to be covered with a pressure line 7 transporting a release liquid. Reliable guidance with elastic restoring force of the nozzle piston 2 is obtained when the piston 2 is guided in a cylinder 8 with a spring 11 acting therein with a spring 11 acting on the inner piston surface 10 facing the cylinder interior 9. The sealing of the line 7, which is under a pressure of, for example, 200 to 400 bar, with respect to the piston 2 or the cylinder interior 9 becomes particularly stable when the line 7 in the form of a precisely fitting socket 12 is brought up to the, for example, cylindrical surface of the nozzle piston 2.

On the circumference of the nozzle piston 2, a seal 14 designed as a connecting piece 13 to a handle or the like is provided. This seal 14 is intended to enclose the body of the nozzle 1 with a precise fit. Furthermore, the underside of the nozzle 1 which is to be faced with the covering to be removed should be designed as a hollow shell 15 in order to ensure that the release liquid is pressed into the covering in a targeted manner. In the exemplary embodiment, a cutting ring 16 is provided as a seal for the hollow shell and an O-ring, e.g. made of rubber, or a surface seal.

2 shows a section through a hand-held device equipped with a plurality of needle nozzles 1. The nozzles 1 are arranged linearly and / or flatly on a carrier element 17 of this device having a handle 18. The carrier element 17 is designed as a hollow body, and its cavity is provided with a connection 19 for a high-pressure feed line of a pump which provides the release liquid.

By pressing the hand-held device according to FIG. 2 against the covering to be removed (on the floor, ceiling or wall), the nozzles 1 movable in the direction of the arrow 6 are pressed into the carrier element 17. Characterized valves of the nozzles 1 are opened to the pressurized cavity of the support member 17, for example the transverse bores come 5 of the nozzle 1 and the leads 7 (shown in FIG. I) is intended to cover, then shoots the under _{'pressurized,} airless conveyed stripping liquid in or by the covering to be removed. This "shot" results in a recoil to the device, which moves the device (against the force of the operator) away from the pad. This in turn pushes the nozzle forward by the spring 11, the liquid supply is interrupted and the device is ready for the next shot.

3 shows a device designed as a machine to be pushed on the floor for detaching a glued floor covering with the aid an airless and impulsive release liquid to be pressed through needle nozzles into the adhesive joint between the covering and the substrate. Here, the entire support element 17 (cf. FIG. 2) is suspended in a roller box 20 in a resilient manner, for example on leaf springs 21 shown symbolically. The roller box 20 has rollers 22. On the underside of the carrier element 17 there are between the rollers 22 nozzles 1 with a vertically downwardly directed nozzle opening 3. Above the carrier element 17 there is provided a cam mechanism symbolically indicated by an eccentric 23, which is directly via a friction wheel 24 is coupled to a roller 22 of the roller box 20. The weight of the roller box 20 can be predetermined by the choice of material. When used in the floor area, the roller box can be weighted down with a water tank or the like.

In the rest position of the machine indicated in FIG. 3, the springs 21 pull the carrier element 17 upward into the roller box 20. However, if this machine is pushed over the covering to be detached, the eccentric 23 coupled to one of the rollers 22 via the friction wheel 24 presses it Support element 17 in the direction of arrow 25 - possibly supported by the relaxation process of springs - downwards. As a result, the nozzles 1 are pressed onto the substrate and the desired injection is triggered. Otherwise, the removal liquid is pressed into the adhesive joint between the covering to be removed and the substrate, in principle, just as in the hand-held device according to FIG. 2.

Reference symbol list

• 1 = nozzle
• 2 = nozzle piston
• 3 = nozzle opening
• 4 = piston cavity
• 5 = cross hole
• 6 = arrow direction
• 7 = pressure line
• 8 = cylinder
• 9 = cylinder interior
• 10 = inner piston surface
• 11 = spring
• 12 = socket
• 13 = connector
• 14 = seal
• 15 = hollow shell
• 16 = cutting ring
• 17 = support element
• 18 = handle
• 19 = pressure connection
• 20 = roller box
• 21 = leaf spring
• 22 = role
• 23 = eccentric
• 24 = friction wheel
• 25 = arrow

Claims (10)

1. Method for the peeling of a covering, which displays a closed surface and is glued to a substrate, with the aid of a detaching fluid issuing from nozzles under high pressure and free of air, characterised thereby, that the detaching fluid is injected in pulsed manner through the covering into the adhesion joint between the covering and the substrate with the aid of at least one needle nozzle (1).

2. Method according to claim 1, characterised thereby, that the pressure of the detaching fluid at the entry of the needle nozzle (1) is set to about 100 to 400 bars.

3. Method according to one of the preceding claims, characterised thereby, that a needle nozzle with a nozzle opening of a diameter of about 0.3 millimetres is used.

4. Method according to one of the preceding claims, characterised thereby, that the detaching fluid is set to be viscous before being pressed into the adhesion joint.

5. Device with nozzles, which deliver detaching fluid under high pressure and free of air, for the peeling of a covering which displays a closed surface and is glued to a substrate, characterised thereby, that it displays at least one needle nozzle (1), which injects a detaching fluid into the adhesion joint between the substrate and the covering, with a nozzle opening (3), which is in particular of a diameter of about 0.3 millimetres and surrounded by a concave hollow cup (15) to be placed onto the covering and which is to be connected, in the manner of a valve with a pressure duct (7) of the detaching fluid through pressing the needle nozzle against the covering to be peeled.

6. Device according to claim 5, characterised thereby, that a knife edge ring (16), an 0-ring, in particular of rubber, or an areal seal is provided as sealing of the hollow cup (15).

7. Device according to one of the preceding claims, characterised thereby, that a pressure pump, which conveys at 200 to 400 bars and free of air, in particular a diaphragm pump or a piston pump, is associated with the pressure duct (7).

8. Device according to one of the preceding claims, characterised thereby, that the needle nozzle (1) is disposed at the end of a nozzle piston (2), which possesses a hollow space (4) and is guided in a cylinder (8) to be movable against a spring force (11), and that the hollow space (4) possesses a transverse bore (5) to be connected to the pressure duct (7) of the detaching fluid by pressing the nozzle piston in against the spring force.

9. Device according to one of the preceding claims, characterised thereby, that two or more needle nozzles (1) are arranged linearly or areally on a carrier element (17) constructed as hollow body connected to a pressure duct (19) of the detaching fluid.

10. Method according to claim 9, characterised thereby, that the carrier element (17) is resiliently suspended in a roller box (20) and that a mechanism is provided, in particular a cam mechanism, which is driven and controlled by the roller and periodically lowers the carrier element (17) during the advance of the box (20).

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