Apparatus and method for removing adhesive layers from finishing materials on concrete surfaces of buildings

Abstract

Conventional removal tools have difficulty completely removing asbestos-containing adhesive layers, especially those that exist under thin paint or flooring materials. The cutting edge tends to slip on the surface of the adhesive layer, and additional sanding work is required with a sander to remove any remaining adhesive layer, resulting in poor work efficiency. [Solution] In this peeling tool, which is attached to a handheld electric impact device, the flat blade base, consisting of the base end side of the joining notch and the front side of the flat blade, is made of die steel, and the cutting edge is made of high-speed steel, allowing the cutting edge to penetrate into the concrete surface even in thin adhesive layers, enabling efficient and reliable peeling and removal of the adhesive layer. Setting the inclination angle of the cutting edge to 15° to 45° enables even more effective removal.

Description

[Technical Field]

[0001] The present invention relates to an apparatus and method for removing an adhesive layer from a finishing material on a concrete surface of a building. [Background technology]

[0002] The paint applied as a finishing material to the concrete surface of a building consists of a main material that forms the outermost layer, and an adhesive layer that adheres the paint to the concrete surface. However, not only the main material but also the surface preparation material may contain asbestos. In addition, flooring materials used as finishing materials for the floors of buildings are also bonded to the concrete surface by an adhesive layer formed between the flooring material and the concrete surface. Flooring materials include tiles and painted floors, and adhesives also include mortar. The adhesive may also contain asbestos to increase its viscosity.

[0003] Asbestos, which is contained in finishing materials such as paints and flooring materials, as well as in the adhesive layers used to adhere these materials to concrete surfaces, can produce dust that is harmful to humans if dispersed during demolition work on buildings, etc., and regulations to prevent its dispersion are established under the Air Pollution Control Act and other laws.

[0004] Therefore, when demolishing a building, demolition companies do not immediately demolish the building, but instead remove finishing materials such as paint and flooring as a preliminary step.This prevents the scattering of asbestos contained in the paint and the flooring and its adhesives during the demolition work, and takes measures to prevent asbestos from remaining in the concrete blocks after the building is demolished.

[0005] As a means for solving such problems, the removal method disclosed in Patent Document 1 was developed.

[0006] The method disclosed in Patent Document 1 is a removal method using a removal tool, which can peel and remove the paint while slightly scraping the concrete.

[0007] In other words, the conventional removal method disclosed in Patent Document 1 involves the cutting edge of the stripping tool striking the concrete surface, slightly scraping it off, for example, at the adhesive boundary between the paint used as a finishing material and the concrete surface. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Japanese Patent Application Laid-Open No. 2024-134050 Summary of the Invention [Problem to be solved by the invention]

[0009] However, it has been found that this conventional removal method may not be effective in some cases, particularly when using a stripping tool whose cutting edge and tip are made of die steel.

[0010] For example, in some areas of the coating, the thickness of the coating down to the concrete surface may be particularly thin. The concrete surface is not perfectly flat, but rather has a certain degree of unevenness (unevenness), resulting in an uneven coating thickness. In areas where the coating is particularly thin (e.g., 0.3 mm or less), conventional tools with cutting edges made solely of die steel would slip on the surface of the surface conditioner before fully penetrating the concrete surface. The surface conditioner also functions as an adhesive to adhere the coating to the concrete surface. However, if the surface conditioner remains as an adhesive layer, the asbestos contained within it also remains, creating a problem.

[0011] Similarly, when it comes to floor materials such as P tiles on floors, conventional tools with cutting edges made only of die steel have a problem in that the cutting edge slips on the surface of the adhesive formed between the floor material and the concrete surface, leaving behind an adhesive layer containing asbestos.

[0012] As a result, the remaining adhesive layer has been removed by grinding it with a sander. However, if the sanding work is required in addition to the method of removing the finishing material and its adhesive layer by striking, it requires extra time and effort.

[0013] The concrete surface to which finishing materials are attached is essentially intended to be formed into a vertical or horizontal (flat) surface when the concrete is poured. For this reason, when fresh concrete is poured into a pre-assembled formwork and allowed to harden, measures are taken to compact it so that it appears vertical to the formwork. This is to prevent distortion (deflection) of the formwork due to the weight of the poured fresh concrete.

[0014] However, in reality, even if such compaction measures are taken, it is difficult to make the concrete surface perfectly vertical. As a result, the concrete surface formed after the formwork is removed is not perfectly flat, but has some unevenness (unevenness).

[0015] In order to create a flat surface on such an uneven concrete surface, a base conditioner is applied, and then the main material is applied on top of that, finally completing the above-mentioned coating that has a flat surface.In the case of a floor, an adhesive is applied to the uneven concrete surface to create a flat surface, and a tile floor or painted floor is completed.

[0016] The thickness of the coating varies according to the unevenness of the concrete surface, with some areas being 2 mm or more, others being half that, at 1.0 mm, and others being particularly thin, at 0.3 mm or less. The inventors' investigations revealed that in areas where the coating is 1.0 mm or less, the cutting edge of a conventional tool with a cutting edge made only of die steel would slip on the surface of the surface conditioner, making it impossible to remove the adhesive layer made of the surface conditioner.

[0017] Furthermore, if you try to use a sander to remove paint that is 0.3 to 1.0 mm thick, which would cause slippage with a conventional cutting edge, the paint is too thick for the sander and is prone to seizing. To avoid this, the sander must be operated multiple times to perform the sanding removal work, with resting periods at regular intervals. This type of sanding removal work is very inefficient. [Means for solving the problem]

[0018] Therefore, as a means for solving the above problem, the adhesive layer removal device of the present invention is a device for removing an adhesive layer from a finishing material adhered to the concrete surface of a building body, and is characterized in that it is configured to have a peeling tool attached to a hand-held electric impact device, and the peeling tool has a main body connected to the electric impact device and a flat blade formed at the tip of the main body, and the back side of the flat blade from the middle position in the thickness direction is formed with a joint notch that runs across the entire width from the middle part in the front-to-back direction to the tip, and the cutting edge is joined to the joint notch, and the flat blade base consisting of the base side and front side part of the flat blade from the joint notch is made of die steel, and the cutting edge is made of high-speed steel, and is configured to perform an impact operation by the front-to-back vibration applied from the impact device.

[0019] Furthermore, as a means for solving the above-mentioned problems, the method of removing an adhesive layer according to the present invention comprises providing a peeling tool on a handheld electric impact device, the peeling tool having a main body connected to the electric impact device and a flat blade formed at the tip of the main body, the back side of the flat blade from the middle position in the thickness direction being formed with a joint notch that runs the entire width from the middle part in the front-to-back direction to the tip, and the cutting edge being joined to the joint notch, the flat blade base consisting of the base side of the joint notch and the front side of the flat blade being made of die steel, and the cutting edge being made of high-speed steel, the cutting edge made of high-speed steel being opposed to the adhesive layer of the finishing material formed on the concrete surface of the building body and abutting it at a predetermined inclination angle, and performing a striking action by applying forward and backward vibrations to the cutting edge from the impact device, thereby continuously peeling off the adhesive layer together with the surface part of the concrete.

[0020] The die steel is an alloy of carbon steel containing alloying elements such as Cr (chromium), Mo (molybdenum), Mn (manganese), Si (silicon), and V (vanadium). For example, JIS standards such as SKD11 and SKD61 can be used. SKD11 is particularly preferred. Meanwhile, the high-speed steel (high-speed tool steel) is an alloy of carbon steel containing alloying elements such as W (tungsten), V (vanadium), and Cr (high chromium). For example, JIS standards such as SKH3 and SKH4 can be used as tungsten-based high-speed steels, and SKH50 and SKH51 can be used as molybdenum-based high-speed steels containing Mo (molybdenum) in addition to the above alloying elements. SKH51 is particularly preferred. SKH51 contains alloying elements such as tungsten, molybdenum, chromium, and vanadium. The carbon steel is preferably an SK material.

[0021] High-speed steel has traditionally been used as a material for cutting tools and molds, and because it is brittle when struck by a striking device, it was difficult to imagine using it for blades for striking devices. However, by combining it with die steel based on the structure of this invention, it can withstand impacts and achieve effects that could not be achieved with tools made solely of conventional die steel.

[0022] Furthermore, the peeling tool may be a tip tool detachably attached to the tip of a handheld electric impact device, and may be configured to perform impacting action by vibrations in the forward and backward directions imparted by the impact device.

[0023] Furthermore, it is preferable that the cutting edge peels off and removes the adhesive layer at the adhesive boundary between the coating and the concrete surface while slightly scraping the concrete by the striking action.

[0024] Furthermore, it is preferable that the inclination angle θ of the cutting edge when the cutting edge is in contact with the adhesive layer is set to 15°≦θ≦45°.

[0025] Furthermore, when the finishing material is a coating, it is also preferable that the coating thickness t includes a portion in the range of 0.3 mm≦t≦1 mm.

[0026] Furthermore, the adhesive layer preferably contains asbestos. [Effects of the Invention]

[0027] According to the present invention, while conventional tools with cutting edges made only of die steel have a structure in which the cutting edge slips on the surface of the adhesive layer, the structure of the present invention, made of die steel and high-speed steel, allows the cutting edge to penetrate all the way to the concrete surface. This makes it possible to peel off the asbestos-containing adhesive layer that exists under thin paint or flooring material in sheet form, and remove it efficiently and reliably. In particular, high-speed steel is a material traditionally used for cutting tools and molds, and because it is brittle when struck by a striking device, it was difficult to imagine using it for blades for striking devices. However, by combining it with die steel based on the structure of the present invention, it can withstand impacts and can even be removed from structures where the cutting edge of a conventional tool made only of die steel would slip on the surface of the adhesive layer.

[0028] In particular, when removing thin paint with a thickness of around 0.3 to 1 mm, it is possible to completely remove the adhesive layer, which was difficult with conventional tools, eliminating the need for additional sanding work using a sander, significantly improving work efficiency. Note that when removing paint thinner than 0.3 mm, it is sufficient to use a sander to perform the removal work.

[0029] Furthermore, since the asbestos-containing adhesive layer can be removed reliably while minimizing scattering, worker safety is improved and it becomes possible to more appropriately comply with regulations such as the Air Pollution Control Act. [Brief explanation of the drawings]

[0030] [Figure 1] 1A and 1B are diagrams showing a method of removing paint using an adhesive layer removal device according to a first embodiment of the present invention, in which (a) is a perspective view showing the state in which paint on the exterior wall of a building is being removed upward, and (b) is a perspective view showing the state in which paint on the exterior wall of a building is being removed downward. [Figure 2] 1A and 1B are cross-sectional views showing the relationship between the cutting edge of a stripping tool according to a first embodiment of the present invention and the coating, where FIG. 1A shows the inclination angle of the cutting edge just before stripping begins, and FIG. 1B shows the inclination angle of the cutting edge as stripping progresses. [Figure 3] FIG. 2 is an enlarged cross-sectional view showing the structure of the coating on the concrete surface. [Figure 4] 1A and 1B are diagrams showing a peeling tool according to a first embodiment of the present invention, in which FIG. 1A is an overall perspective view, and FIG. 1B is an enlarged perspective view of a flat blade. [Figure 5]1A, 1B, and 1C are diagrams showing the configuration of a flat blade of a peeling tool according to a first embodiment of the present invention, in which FIG. 1A is a plan view, FIG. 1B is a side view, and FIG. 1C is a bottom view. [Figure 6] 1 is a perspective view showing the overall configuration of an adhesive layer removal device according to a first embodiment of the present invention; [Figure 7] 1A and 1B are diagrams showing a conventional tool having a flat blade made only of die steel, where (a) is a plan view and (b) is a side view. [Figure 8] 1 is a photograph showing an example of the first embodiment of the present invention, where (a) shows the area where the present invention was implemented, and (b) shows the area where a conventional technique using a flat blade made only of die steel was implemented. The value indicated by the electronic caliper is 0.47 mm, and the photograph shows the state where the thickness of the coated piece in this embodiment is being measured by clamping it. [Figure 9] 1 is a photograph showing an example of the first embodiment of the present invention, where (a) shows the area where the present invention was implemented and (b) shows the area where a conventional technique using a flat blade made only of die steel was implemented. In this figure, it can be seen that the paint has peeled off in area (a), exposing the concrete on the exterior wall of the building, while in area (b) the adhesive layer, which is a surface preparation material, remains. [Figure 10] This is a photograph showing the backside of a flat blade according to the present invention. The boundary line of the joining notch is visible above the sticky note f, and the cutting edge made of high-speed steel is located above the joining notch. [Figure 11] 10 is a photograph showing an example of the second embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0031] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In this specification and drawings, components having substantially the same functional configurations are designated by the same reference numerals, and redundant description will be omitted.

[0032] As shown in Figure 6, the adhesive layer removal device according to the present invention is configured by providing a peeling tool 2 on a handheld electric impact device 6. The electric impact device 6 has a main body 8, an operating unit 9, a trigger 10, and a power cord 11. The peeling tool 2 is detachably attached to a tip 6a of the electric impact device 6. The electric impact device 6 may also be a battery-powered, rechargeable electric impact device.

[0033] As shown in Fig. 4(a), the peeling tool 2 has a main body 5 (shank 5) connected to an electric impact device 6, and a flat blade 3 formed at the tip of the main body 5. A cutting edge 4 is formed at the tip of the flat blade 3. Fig. 4(b) is an enlarged perspective view of the flat blade 3.

[0034] FIG. 5(a) is a plan view of the flat blade 3, FIG. 5(b) is a side view, and FIG. 5(c) is a bottom view. As shown in FIGS. 5(b) and 5(c), a notch 7 is formed on the back side of the flat blade 3 from the midpoint in the thickness direction, spanning the entire width from the midpoint in the front-rear direction to the tip. The cutting edge 4 is joined to this notch 7. Brazing is preferred as a method for joining the cutting edge 4. The flat blade base 3a (excluding the part of the flat blade 3 where the cutting edge 4 is joined), consisting of the base end side of the notch 7 and the front side of the flat blade 3, is made of die steel. This die steel is an alloy containing alloying elements such as Cr (chromium), Mo (molybdenum), Mn (manganese), Si (silicon), and V (vanadium) in addition to carbon steel. For example, JIS standard SKD11 or SKD61 can be used. SKD11 is particularly preferred. On the other hand, the high-speed steel (high-speed tool steel) is an alloy of carbon steel containing alloying elements such as W (tungsten), V (vanadium), and Cr (high chromium). For example, it can be selected from tungsten-based high-speed steels such as JIS standard SKH3 and SKH4, and molybdenum-based high-speed steels such as SKH50 and SKH51, which contain Mo (molybdenum) in addition to the alloying elements. SKH51 is particularly preferred. SKH51 contains alloying elements such as tungsten, molybdenum, chromium, and vanadium. SK material is preferred as the carbon steel. This allows the cutting edge 4 made of high-speed steel to penetrate all the way to the concrete surface Ca, even on thin coating 12 that would have slipped with a conventional cutting edge made only of die steel, and ensures the removal of the surface preparation material 12a, which is the adhesive layer 14. In a preferred embodiment, the flat blade base 3a in FIG. 5 can be made of SKD11 and the cutting edge 4 can be made of SKH51.

[0035] Here, the structure in which the cutting edge 4 made of high-speed steel is joined to the joint notch 7, i.e., the flat blade base 3a on the base side and on the front side of the high-speed steel (cutting edge 4) is made of die steel, is a composite structure that is thought to be effective in preventing the high-speed steel from being damaged by impacts in the forward and backward directions, and in enabling it to bite into the concrete surface Ca even under conditions in which a conventional cutting edge made only of die steel would slip.

[0036] On the other hand, Figure 7 shows an outline of the structure of a conventional tool using a flat blade made only of die steel. That is, the flat blade 3 is made entirely of die steel.

[0037] 10 is a photograph showing the back surface of the flat blade 3 according to the present invention. The boundary line of the joining notch 7 is visible above the sticky note f on the paper, and it can be seen that the cutting edge 4 made of high-speed steel is located above the joining notch 7 on the paper.

[0038] The electric impact device 6 receives power via a power cord 11, and by operating the trigger 10, it applies vibrations back and forth to the stripping tool 2 via the main body 5, performing an impact motion. This impact motion causes the cutting edge 4 to remove the adhesive layer of the coating 12 (finishing material) adhered to the surface Ca of the concrete exterior wall C of a building, as shown in FIGS. 1(a) and 1(b). Note that while this embodiment describes a case where the coating 12 is applied to an exterior wall, the same applies to coating 12 applied to the concrete surface that constitutes an interior wall or floor.

[0039] Fig. 2(a) is a cross-sectional view showing the state immediately before starting to peel off the coating 12. The operator holds the peeling tool 2 by hand and abuts the cutting edge 4 against the coating 12. As shown in Fig. 2(a), the inclination angle θ of the cutting edge 4 when it is abutting against the coating 12 is preferably set to 15°≦θ≦45°.

[0040] FIG. 1(a) is a perspective view showing the state of the paint 12 as it peels upwards on the exterior wall. FIG. 1(b) is a perspective view showing the state of the paint 12 as it peels downwards on the exterior wall. The forward and backward vibrations applied by the electric impact device 6 cause the cutting edge 4 to perform an impact action, slightly scraping the concrete C at the adhesive boundary between the paint 12 and the concrete C, while peeling and removing the paint 12 in sheets along with the concrete surface Ca. This causes the peeled paint 12 to be continuously peeled off. FIG. 2(b) is a cross-sectional view showing the inclination angle of the cutting edge 4 as it peels.

[0041] 3 shows the cross-sectional structure of the coating 12 applied to the concrete C in this embodiment. A surface preparation material 12a is applied to the surface of the concrete C, and a main material 12b is further applied to the surface of the surface preparation material 12a, forming a layered structure. Here, the surface preparation material 12a constitutes an adhesive layer 14. In this embodiment, the cutting edge 4 joined to the joining notch 7 of the removal tool 2 is made of high-speed steel, and the flat blade base 3a is made of die steel. This allows the cutting edge 4 to penetrate into the concrete surface Ca without slipping on the surface of the surface conditioner 12a serving as the adhesive layer 14, even when the coating 12 is thin, such as in a region where the thickness T1 is 0.3 mm≦T1≦1 mm (see FIG. 3), and reliably remove the adhesive layer 14 (surface conditioner 12a). Examples of coating surface conditioners include cement-based and synthetic resin emulsion-based materials.

[0042] Figure 8 is a photograph showing an example of this embodiment. Figure 8(a) shows the area where the present invention was implemented, and Figure 8(b) shows the area where the conventional technique using a flat blade made only of die steel was implemented. In the area of ​​Figure 8(a), the coating 12 has been peeled off, exposing the concrete C. The value indicated by the electronic caliper is 0.47 mm, showing the state in which the coating piece in this embodiment is clamped and the thickness is measured. This thickness of 0.47 mm is within the range of thin coating thicknesses that are prone to slippage with conventional tools.

[0043] Figure 9 is also a photograph showing an example of this embodiment. Figure 9(a) shows the area where the present invention was implemented, and Figure 9(b) shows the area where the conventional technique using a flat blade made only of die steel was implemented. In area (a), it can be seen that the paint 12 has been completely peeled off in sheets, exposing the concrete C on the exterior wall of the building. On the other hand, in area (b), it can be seen that the adhesive layer 14, which is a surface preparation material, remains. This indicates that it is difficult to completely remove the adhesive layer underneath the thin paint using conventional tools.

[0044] FIG. 11 is a photograph showing an example of the second embodiment of the present invention. This embodiment shows the adhesive layer 14 of floor tiles P being removed in sheet form. As with removing paint, the high-speed steel cutting edge 4 penetrates between the adhesive layer 14 and the concrete surface Ca, efficiently peeling and removing the adhesive layer 14. This ensures that even asbestos-containing adhesive layers present underneath the flooring material can be removed reliably. In the second embodiment, the adhesive layer includes, for example, an adhesive primarily made of epoxy resin, or mortar. Note that the second example shows a finishing material made of tiles, but it can also be applied to painted floors.

[0045] In this way, the adhesive layer removal method and adhesive layer removal device of the present invention enable efficient and reliable removal of adhesive layers that may contain asbestos. This is particularly effective for thin adhesive layers that are difficult to remove with conventional tools, significantly reducing the time and effort required for demolition work and contributing to a safer working environment. [Explanation of symbols]

[0046] C. Exterior wall concrete Ca exterior wall concrete surface T1 Paint Thickness T0 Minimum thickness of paint peeling 1. Painting 2. Removal tool 3 Flat blade 3a flat blade base 4 cutting edge 5 Main body (shank) 6 Electric Percussion Device 6a Tip of electric impact device 7 Joint notch 8 Main body 9 Control section 10 Triggers 11 Power cord 12 Painting 12a Base preparation material 12b Main material 14 Adhesive layer P-tile

Claims

1. A device for removing an adhesive layer of a finishing material adhered to the concrete surface of a building body, A peeling tool is provided on a handheld electric impact device, The peeling tool has a main body connected to the electric impact device and a flat blade formed at a tip of the main body, A back side portion of the flat blade from a middle position in the thickness direction is formed with a joint notch extending over the entire width from the middle portion in the front-rear direction to the tip, and the cutting edge is joined to the joint notch, a flat blade base portion including a base end side of the joining notch and a front side portion of the flat blade is made of die steel, The cutting edge is formed from high-speed steel, The impact action is performed by the forward and backward vibrations applied from the electric impact device. An adhesive layer removal device characterized by:

2. A peeling tool is provided on a handheld electric impact device, The peeling tool has a main body connected to the electric impact device and a flat blade formed at a tip of the main body, A back side portion of the flat blade from a middle position in the thickness direction is formed with a joint notch extending over the entire width from the middle portion in the front-rear direction to the tip, and the cutting edge is joined to the joint notch, a flat blade base portion including a base end side of the joining notch and a front side portion of the flat blade is made of die steel, The cutting edge is formed from high-speed steel, The cutting edge made of high-speed steel is opposed to the adhesive layer of the finishing material formed on the concrete surface of the building body and butted against it at a predetermined inclination angle, and a striking action is performed by applying back and forth vibrations to the cutting edge from the electric impact device, thereby continuously peeling off the adhesive layer along with the surface portion of the concrete. A method for removing an adhesive layer.

3. The peeling tool is a tip tool detachably attached to the tip of a handheld electric impact device, and is configured to perform impact operations by forward and backward vibrations applied from the electric impact device. The method for removing an adhesive layer according to claim 2 .

4. The blade tip, by the striking action, peels off and removes the adhesive layer at the adhesive boundary between the coating and the concrete surface while slightly scraping the concrete. The method for removing an adhesive layer according to claim 2 .

5. The inclination angle θ of the cutting edge when the cutting edge is in contact with the adhesive layer is set to 15°≦θ≦45°. The method for removing an adhesive layer according to claim 2 .

6. In the case where the finishing material is a paint, the thickness t of the paint includes a portion in the range of 0.3 mm≦t≦1 mm. The method for removing an adhesive layer according to claim 2 .

7. The adhesive layer contains asbestos The method for removing an adhesive layer according to claim 2 .

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