DK202001073A1 - Apparatus and method to reset a floor or repair a cracked wall - Google Patents

Abstract

The invention relates to an apparatus for filling a void or crack in a building structure. The apparatus comprises an injection nozzle, a cartridge with a liquid adhesive in its lumen, a cartridge, and a caulking gun or the like adapted for forcing said adhesive out of the cartridge. The injection nozzle is needle-shaped with a hollow shaft and a hub. The hub is threaded and adapted for being directly or indirectly fastened to the outlet of said cartridge. The adhesive in the cartridge has a shear-thinning rheological behavior.

Description

DK 2020 01073 A1 Apparatus and method to reset a floor or repair a cracked wall Field of the Invention The present invention relates to the field of repair tools for walls and floors.

Background of the Invention Traditional methods for repairing a floor where the flooring material has become separated from subfloor, such as a concrete slab, usually involve removing the flooring material from the subfloor and cleaning both the subfloor and the flooring material, then reinstalling the flooring material. In some situations, the flooring material cannot be reinstalled, which then requires finding matching replacement flooring material or replacing all the flooring material. Similarly, methods for repairing cracked walls involve removing a part of the wall material delimiting the crack, and then filling the created recess with a filler material, often having inferior mechanical properties than the original material or at least resulting in a wall that may very easily crack in the same spot again due to the original material and the filler material having different mechanical properties. More recent methods for repairing a floor where the flooring material has become separated from the subfloor include delivering a liquid adhesive between the flooring material and the subfloor via a hole drilled in the floor while leaving the flooring material in place. The liquid adhesive is then allowed to set, thereby adhering the flooring material to the subfloor. A method like this is disclosed in US9151066. However, this method suffers from inadequate filling of the void between the subfloor and the flooring material. The flooring may be fastened to a certain extent, but the flooring will still sound hollow, especially when the flooring material comprises large tiles with a width of more than 20 cm.

, DK 2020 01073 A1 Object of the Invention The objective of the present invention is therefore to provide an apparatus and a method for repairing a tile floor that sounds hollow. Description of the Invention A first aspect relates to an apparatus for filling a void or crack in a building structure, such as a floor or a wall, said apparatus comprising: - an injection nozzle; - a cartridge with a liquid adhesive in its lumen, said cartridge comprising a threaded outlet; and - a caulking gun or the like adapted for forcing said adhesive out of the outlet of said cartridge; wherein said injection nozzle is needle-shaped with a hollow shaft and a hub; wherein said hub is threaded and adapted for being directly or indirectly fastened to the outlet of said cartridge. Preferably, the adhesive has a shear-thinning rheological behavior and more preferably the adhesive has a thixotropic rheological behavior.

As used herein, the term “shear thinning” refers to the common property of non- Newtonian fluids where fluid viscosity decreases with increasing shear rate or shear stress. As used herein, the term “thixotropic” is used to describe an adhesive, which fluid viscosity decreases with increasing shear rate or shear stress, and then increase again when left standing.

The rheological properties of the liquid adhesive for use in the present invention is of great importance. For the adhesive to flow easily into the void after being forced out of the needle, it should have a shear-thinning rheological behavior and more preferably a thixotropic rheological behavior. The present invention describes the use of a caulking gun to force the liquid adhesive out of the cartridge and through a very thin needle, preferably 0.5-2.0 mm in thickness, and more preferably 1.0-1.5 mm in thickness. This operation provides sufficient shear

2 DK 2020 01073 A1 stress to make the liquid adhesive flow easily and fast into all areas of the void or crack. When the adhesive rests, its fluid viscosity increases again and its properties as an adhesive are restored. Hence, the shear rate is induced by pumping, but could be combined by mixing, provided that a static mixer is introduced between the needle and cartridge. The shear rate will reduce the viscosity, allowing the adhesive to flow more easily. The pumping, optionally in combination with static mixing, is speculated, without being bound to it, to generate shear rates of from 100 to 10,000 second. When the application is finished and the shear rate falls off to only that induced by gravity, the viscosity will build up again to help hold the adhesive in place until it has cured.

The caulking gun/sealant gun is a familiar tool to workers in the construction industry. It is a simple means of dispensing pastes from standard sized cartridges. The cartridge is secured in the gun; and squeezing or triggering the handle depresses a plunger at the base of the adhesive cartridge that forces the paste out through the cartridge nozzle. Guns are available for a range of standard size one or two component adhesive cartridges. The simplest guns are manually driven but pneumatically or motor driven systems are also available.

In one or more embodiments, the adhesive has a viscosity of less than 3,000 mPa*s when measured at 20° Celsius at a shear rate of 100 second", and preferably within the range of 100-3,000 mPa*s when measured at 20° Celsius at a shear rate of 100 second", and even more preferably within the range of 200- 2,000 mPa*s when measured at 20° Celsius at a shear rate of 100 second", such as within the range of 200-1,000 mPa*s when measured at 20° Celsius at a shear rate of 100 second, e.g. within the range of 400-800 mPa*s when measured at 20° Celsius at a shear rate of 100 second!. The viscosity may be measured by an Anton Paar Rheometer (Physica MCR 302) using a measuring bob and cup (system CC27). Adhesives with these characteristics are well known to the skilled person with the field of adhesives and are commercially

1 DK 2020 01073 A1 available. A suitable type of adhesives could e.g. be a cyanoacrylate that is an enclosed cure adhesive, based on acrylic monomer, that polymerizes into an acrylic polymer in contact with alkaline surfaces, such as cement. The presence of surface moisture helps neutralize acidic stabilizers in the adhesive and promote the hardening reaction. The rheological properties of the adhesive may be controlled by using so-called “rheological control agents” or “thixotropes” as additives. Several commercially available thixotropes, such as fumed silica, talc, asbestos, modified bentonite, colloidal silica and certain hydrated magnesium aluminum silicates, can be utilized to impart the desired rheological characteristics for the adhesive for use in the present invention. A preferred thixotrope is fumed silica. It has the advantages of being an effective rheological control agent, which will not undergo swelling, and which exhibits chemical inertness.

When compared to the injection nozzle disclosed in US9151066, the injection nozzle of the present invention is needle shaped. This difference is very important as the thin needle, preferably 0.5-3.0 mm in thickness, and more preferably 1.0-2.5 mm in thickness, e.g. 1.0-1.5 mm in thickness secures that sufficient shear stress is provided to make the liquid adhesive flow easily and fast into all areas of the void or crack. This will not happen when using a conical tip disclosed in US9151066. The needle is preferably straight to avoid that the flow of adhesive is slowed down before reaching its destination. Preferably, the needle is made from metal, such as stainless steel.

In one or more embodiments, the apparatus further comprises a kit of injection nozzles of different thicknesses within the range of 0.5-3.0, such as within the range of 1.1-2.4 mm.

In one or more embodiments, the needle-shaped injection nozzle has a blunt tip.

This embodiment allows for a controlled and uniform flow of adhesive from the needle tip compared to a needle with a bevel. To avoid that the needle tip during

É DK 2020 01073 A1 insertion into the hole or crack is clogged with filler material or material from the wall or subfloor, the injection nozzle preferably comprises a side port positioned at most 1-10 mm from the tip end, and more preferably 2-5 mm from the tip end. This position also secures that the adhesive may flow directly into the void below a tile as it corresponds to the height of the original glue layer. In one or more embodiments, the injection nozzle has a closed ended tip with one or more side ports positioned at most 1-10 mm from the tip end, and more preferably 2-5 mm from the tip end.

When using such relatively small needles as injection nozzles, they may become worn relatively fast. To avoid having to change the entire injection nozzle, it can be divided into a needle part and an adapter part, such as a threaded bushing, where only the needle part is to be replaced. This configuration is also suitable when there is a need for different types of needles for different types of work, depending on whether it is a wall or a flooring that needs to be repaired.

In one or more embodiments, the injection nozzle is adapted for being indirectly fastened to the outlet of said cartridge via an adapter having a first end and a second end, and wherein said adapter is threaded in both ends.

A second aspect relates to a method for repairing a portion of a floor where one or more tiles have become separated from a subfloor, the method comprising the steps of: - determining the position of a void between said one or more tiles and said subfloor; - drilling an injector hole of 1-2.5 mm in the filler material between tiles positioned above said void; - providing an apparatus according to the present invention; - injecting liquid adhesive of said apparatus into said void via said injector hole and via the needle-shaped injection nozzle of said apparatus, said injection nozzle having a diameter corresponding to said injector hole;

. DK 2020 01073 A1 - removing said injection nozzle from said injector hole to allow said liquid adhesive to increase in viscosity; and - allowing said liquid adhesive to set. In one or more embodiments, the liquid adhesive is preheated to a temperature of 15-30 degrees Celsius prior to injection. A third aspect relates to a method for repairing a portion of a building structure, such as a wall or a floor, where a crack has formed, the method comprising the steps of: - determining the position of the crack in said building structure; - drilling an injector hole of 1-2.5 mm into said crack; - providing an apparatus according to the present invention; - injecting liquid adhesive of said apparatus into said crack via said injector hole and via the needle-shaped injection nozzle of said apparatus, said injection nozzle having a diameter corresponding to said injector hole; - removing said injection nozzle from said injector hole to allow said liquid adhesive to increase in viscosity; and - allowing said liquid adhesive to set.

In one or more embodiments, the liquid adhesive is preheated to a temperature of 15-30 degrees Celsius prior to injection.

As used in the specification and the appended claims, the singular forms "a", "an", and "the" include plural referents unless the context clearly dictates otherwise. Ranges may be expressed herein as from "about" or "approximately" one particular value and/or to "about" or "approximately" another particular value. When such a range is expressed, another embodiment includes from the one particular value and/or to the other particular value. Similarly, when values are expressed as approximations, by use of the antecedent "about", it will be understood that the particular value forms another embodiment.

, DK 2020 01073 A1 It should be noted that embodiments and features described in the context of one of the aspects of the present invention also apply to the other aspects of the invention.

The invention is described in more detail in the following detailed description of a preferred embodiment, with reference to the figures. Brief description of the figures Figure 1 is a schematic drawing of a floor to be repaired; Figure 2 shows a cross-sectional view of an injection nozzle, adapter, and adhesive cartridge according to specific embodiments of the present invention; and Figure 3 shows an adhesive cartridge to be inserted into a caulking gun according to specific embodiments of the present invention. References 110 Outline 120 Tile 130 Injector hole 140 Filler material line 150 Injection nozzle 160 Adapter 170 Cartridge 180 Gun g DK 2020 01073 A1 Detailed Description of the Invention Figure 1 shows a tile floor to be repaired. At first the repairer will have to determine the location and extent of a separated area under the tile floor. Such areas may vary much in size as exemplified with area A and B. This is done by tapping the tiles 120 on the floor with a solid object (not shown), thereby finding the outline 110A, 110B of the separated area by sound. While tapping the outline of the separated area it can be marked by chalk or other removable material. The repairer would then select a starting point in the separated area and drill an injector hole 130A, 130B in the filler material line 140 between adjacent tiles 120.

If the separated area is relatively large as exemplified with area B, it may be necessary to drill more than a single injector hole. However, due to the apparatus' construction of the present invention the adhesive flows very easily into the separated area, thereby obviating the need for drilling many injector holes. Before injecting the adhesive, the drilled injector hole is preferably cleaned from dust, e.g. by vacuum suction. Contrary to the method disclosed in US9151066 there is no need for drilling ventilation holes and there is no need for a seal or tight fit between the injector nozzle and the injector hole. This is because the injected adhesive flows readily from the injector hole and throughout the separated area as exemplified with arrows in area A. As the adhesive flows readily, and the lack of said tight fit, there is little risk of pressure increases resulting in the breakage of filler material lines or lifting of tiles in the separated area. Figure 2 shows a cross-sectional view of a part of the system according to specific embodiments of the present invention, i.e. an injection nozzle 150, adapter 160, and cartridge 170. The injection nozzle 150 is adapted for being indirectly fastened to the outlet of the cartridge 170 via an adapter 160, here embodied as a threaded bushing. The adapter 160 is threaded in both ends.

Figure 3 shows the cartridge 170 about to be inserted into a caulking gun 180 (only the front part is shown). The injection nozzle and adapter are not shown.

Claims (10)

o DK 2020 01073 A1 Claims

1. An apparatus for filling a void or crack in a building structure, said apparatus comprising: - an injection nozzle; - a cartridge with a liquid adhesive in its lumen, said cartridge comprising a threaded outlet; and - a caulking gun or the like adapted for forcing said adhesive out of the outlet of said cartridge; characterized in that said injection nozzle is needle-shaped with a hollow shaft and a hub; wherein said hub is threaded and adapted for being directly or indirectly fastened to the outlet of said cartridge; wherein said adhesive has a shear-thinning rheological behavior.

2. The apparatus according to claim 1, further comprising an oven adapted for heating said cartridge to a temperature of 15-30 degrees Celsius.

3. The apparatus according to claim 1, wherein said injection nozzle comprises a side port positioned at most 1-10 mm from the tip end.

4. The apparatus according to claim 3, wherein said injection nozzle has a closed ended tip with one or more side ports positioned at most 1-10 mm from the tip end.

5. The apparatus according to any one of the claims 1-4, wherein said adhesive has a thixotropic rheological behavior.

6. The apparatus according to any one of the claims 1-5, wherein said injection nozzle is adapted for being indirectly fastened to the outlet of said cartridge via an adapter, such as a threaded bushing, having a first end and a second end, and wherein said adapter is threaded in both ends.

0 DK 2020 01073 A1

7. A method for repairing a portion of a floor where one or more tiles have become separated from a subfloor, the method comprising the steps of: - determining the position of a void between said one or more tiles and said subfloor; - drilling an injector hole of 1-2.5 mm in the filler material between tiles positioned above said void; - providing an apparatus according to any one of the claims 1-6; - injecting liquid adhesive of said apparatus into said void via said injector hole and via the needle-shaped injection nozzle of said apparatus, said injection nozzle having a diameter corresponding to said injector hole; - removing said injection nozzle from said injector hole to allow said liquid adhesive to increase in viscosity; and - allowing said liquid adhesive to set.

8. The method according to claim 7, wherein said liquid adhesive is preheated to a temperature of 15-30 degrees Celsius prior to injection.

9. A method for repairing a portion of a building structure, such as a wall or a floor, where a crack has formed, the method comprising the steps of: - determining the position of the crack in said building structure; - drilling an injector hole of 1-2.5 mm into said crack; - providing an apparatus according to any one of the claims 1-6; - injecting liquid adhesive of said apparatus into said crack via said injector hole and via the needle-shaped injection nozzle of said apparatus, said injection nozzle having a diameter corresponding to said injector hole; - removing said injection nozzle from said injector hole to allow said liquid adhesive to increase in viscosity; and - allowing said liquid adhesive to set.

10. The method according to claim 9, wherein said liquid adhesive is preheated in an oven to a temperature of 15-30 degrees Celsius prior to injection.