METHOD FOR CASTING A SLOPE

Technical Field

The present invention relates to a procedure for manufacturing a device intended to be used for casting a slope of a floor with a correct inclination toward a floor drain.

Also, the present invention relates to a device, intended to be used for casting a slope of a floor toward a floor drain, comprising a bottom surface which corresponds to the inclination of the slope and a part that is arranged at said bottom surface for arrangement to the floor drain.

Also, the invention relates to a method for casting a slope of a floor toward a floor drain by using a device manufactured according to the procedure. Background of the invention

In different types of rooms or spaces in an ordinary house or in other buildings, such as garages, sport halls, swimming arenas, and industrial facilities or plants, there is a need for one or more floor drains arranged into the floor for discharging water. For example, floor drains are necessary in shower rooms, bathrooms, lavatories, laundry rooms, garages, or in floors of balconies and terraces, where waste water, excess water or rain water can be pooled and then must be discharged. The floor of such a space or an area is designed to allow water to flow towards the floor drain or waste water outlet.

In most cases, said floors are constructed by firstly produce an under floor made of cement, concrete or similar material. A floor drain is then arranged in the concrete floor. Thereafter, a slope toward the floor drain is constructed by use of solid putty or solid spackling paste to form an inclined part of the floor, which is manually made by hand. An upper layer is then applied by supplying floating putty or floating spackling paste on top of the inclined part and on the rest of the floor for adapting the slope in alignment with the rest of the floor and for providing a smooth surface of the floor. Finally, a top layer may be provided by titles, hard-burned bricks or clinkers with joint filling material between these.

The difficulty in obtaining a symmetric slope toward and around the floor drain in accordance to construction standards is a well-known problem, since the slope often is manually made and the result depends on the skill of the person performing the work.

Experienced craftsmen can produce such floors so that the floor drops evenly toward the floor drain according to determined construction standards, which for example is a requirement for a shower area. It is a well-known fact that a skilled person within the art cannot reproduce the same slope at every occasion since it is made by hand, and also that this is a laborious and time consuming moment despite long experience. A less skilled person or a trainee needs more time, and problems can arise to reach construction standards.

Floors that are inclined too steeply are uncomfortable and are a slipping risk for a user of for example a shower, and a floor that are not inclined enough results in a poor drain. A slope that is unsymmetrical around the floor drain results in pooling of water in corners of the wet area or tends to pool water in other undesired areas. This can lead to cracks in the joint filling material and to mildew arising into the cracks, or even worse; overflow in adjacent rooms.

SE470216 describes a method for making a slope toward a floor drain when casting a floor. To produce the slope, a form is fixed by fastening means to the floor drain. The form has a circumferential reinforcement for keeping its stability when cement is supplied around and under the form at casting.

The Swedish patent application SE1 100231-8 describes a cone shaped casting form for casting a sloped floor toward a floor drain. The casting form with a tip is placed over a floor drain to which the tip is attached. When floating putty or cement has been supplied and has dried, the material under the casting form obtains the same angle as the casting form.

US6568140 shows a plate with an inclined bottom surface. The plate is used as a form to obtain a drop of the slope toward a floor drain when casting cement floors. The bottom side of the plate provides a fan shaped gradient into the cement under the form toward the floor drain.

The existing forms on the market for casting a slope toward a floor drain have limitations since existing models only show a weak stability and hence have limited usability.

There is a strong demand within the building trade to find an effective and time saving way for making a slope toward a floor drain by means of a device and to repetitively reach approved standard, which also is ergonomic and simple to apply for a professional worker within this field.

Summary of the invention

An object of the present invention is to mitigate or eliminate one or more deficiencies and disadvantages of the prior art, and to provide a procedure for manufacturing a device intended to be used for casting a slope with correct inclination toward a floor drain according to claim 1.

A more specific object of the present invention is to provide a procedure for manufacturing a device intended to be used for casting a slope with correct inclination toward a floor drain, where the device comprises a bottom surface which corresponds to the inclination of the slope and a part that is arranged at said bottom surface for connection to the floor drain. The procedure comprises to provide an element having a first and a second sheet of metal foil, which are arranged in parallel to each other, and a core of polymeric material between the first and second sheet. A through circular hole is made into the element, and is arranged at the center of the element. Several grooves are made into the first sheet, which are arranged along their lengths between an outer circumference of the element and the circular hole to allow the polymeric material of the core to flow out into the groves. The grooves are symmetrical arranged, and has a width of 1 to 10 mm, preferably 2 to 6 mm. The number of grooves may vary, for example 4 to 16, and according to a preferred embodiment the number is 8.

Heat is supplied to the element, for example by radiation such as infrared (IR) radiation, induction, convection or conduction, and also hybrid solutions can exist. A pressure force is applied to the first sheet of metal foil for forming the sheets of metal foil so that the bottom surface of the element corresponds to an inclination that provides a correct slope toward the floor drain, and simultaneously for bending the edges of the circular hole downwards forming a tubular part intended to be connected to the floor drain. During the form pressing, the polymeric material is allowed to flow out into the grooves of the first sheet in a zone adjacent to the tubular part close to the circular hole. The preheating temperature on the sheet is adapted so that the zones which require the largest change in form will get a higher temperature. When using IR-radiation, this is made by applying a dark layer, such as dark color or a dark foil layer, to said zone surrounding the circular hole, before supplying heat, for increasing the ability of the element to absorb heat in this zone, when heat is supplied, and in such way increase the formability of the element.

The pressure force is applied by means of a pressing tool. The metal foils serve as cooling flanges during the cooling of the device, which will reduce the time for production of the device.

In a second aspect the invention relates to a device, which is manufactured according to the procedure and which is intended to be used at casting a slope of o floor toward a floor drain, wherein the device comprises a bottom surface that corresponds to the inclination of the slope and a part that is arranged at said bottom surface intended for connection to the floor drain.

In a third aspect the invention relates to a method for casting a slope of a floor toward a floor drain by using a device manufactured according to the procedure. The method comprises to provide the device with a bottom surface, which corresponds to the inclination of the slope, and a tubular part for connecting to the floor drain, and then to connect the device to the floor drain. Further, levelling-screws are provided, which are arranged in the grooves at the outer circumference of the device and which are going through the polymeric core and said second metal foil, and by which the device is horizontally aligned in relation to the floor. By means of the levelling-screws the device is aligned in relation to the floor to secure that the bottom surface of the device will take and maintain a correct inclination. Floating putty is supplied so that the interspace between the device and the floor is filled in, finally the levelling-screws are cut off and the device is removed when the floating putty has solidified.

Further objects, features and advantages of the present invention will appear from the following detailed description, the attached drawings and the dependent claims.

Brief description of the drawings

In order to explain the invention, embodiments of the invention will be described below with reference to the drawings, in which:

Fig 1 shows schematically an element of a device intended to be used for casting a slope toward a floor drain,

Fig 2 shows schematically the element of the device in Fig 1 , which has been provided with grooves in a first sheet and a trough hole,

Fig 3 shows schematically the element in Fig 1 according to an alternative

embodiment,

Fig 4 shows schematically the device arranged to the floor drain at casting the slope toward the floor drain, and

Fig 5 shows schematically the finished slope toward the floor drain.

Same reference numerals have been used to indicate the same parts in the figures to increase the readability of the description and for the sake of clarity.

Description of embodiments of the invention

A procedure for manufacturing a device 40 intended to be used for casting a slope with a correct inclination toward a floor drain 41 according to the invention will be described below with reference to the drawings.

The device comprising a bottom surface 42 that corresponds to the inclination of the slope and a part 44, which is arranged at said bottom surface for connection to the floor drain and which is produced according to the procedure, will also be described.

A method for casting a slope toward a floor drain by means of the device 40 that is manufactured by the procedure will then be described.

Elements with a good flexural rigidity and a good bending strength, while

simultaneously other criteria such as low weight and low price must be satisfied, are available as prefabricated elements for use within different types of construction. One example is sandwich structures comprising sheet elements with different properties. Since such an element also must present properties as being formable by means of different technologies where the final product must have a specific shape with maintained flexural rigidity, a deeper material knowledge is required for choosing material and process technology to obtain the final product with desired properties at casting.

A device 40 that is intended to be used at casting a slope of a floor 43 must have a specific inclination of a bottom surface 42 which corresponds to the slope of the floor. By using a prefabricated element 10 comprising two sheets of metal foil 1 1 , 12 that are arranged in parallel with a polymeric core 13 arranged between said sheets, the device can be manufactured according to the invention.

Fig 1 shows an element 10 that will be used as a blank for producing the device. The element comprises a first sheet 1 1 and a second sheet 12, which both are made of metal foil and are arranged in parallel with each other. Further, the element comprises a polymeric core

13 that is arranged between said first and second metal foil. The sheets are for example made of aluminum, or an alloy of aluminum and another metal. The element has a thickness of about 3-5 mm as a prefabricated blank, according to a first embodiment the thickness is 4 mm, which means that it is light and simultaneously has stiffness. The element is square according to the first embodiment, and has a width and a length of 1000-1500 mm, respectively, preferably 1200 mm. This size of the element ensures that a slope toward a floor drain with a correct inclination can be produced without later adjustment of the slope, since the element is able to cover the entire area surrounding the drain.

The procedure for manufacture of the device is initiated by providing an element 10 according to Fig 1. Then, a through hole 20 is made in the element by means of a cutting tool or a boring tool. The hole is arranged in the center of the element according to a first embodiment, and has a diameter of 10-16 mm, preferably 14 mm.

Thereafter, grooves 21 are made in the first sheet 1 1 of the element. The grooves are arranged between the outer circumference of the element and the circular hole 20. Said grooves are going through the sheet according to a first embodiment, and are symmetrically arranged between the outer circumference of the element and the circular hole. The grooves have a width of 1-10 mm, preferably 4 mm. The grooves are arranged for increasing the formability of the element during heating, which will be explained in detail below. According to an alternative embodiment, the grooves can be made through only in some parts of the grooves, while being not through in the remaining parts.

Fig 2 shows a device with four grooves which are through, and which are arranged between the middle of the sides of the element and the circular hole.

Fig 3 shows a device with eight grooves which are through, and which are arranged between the middle of the sides of the element and the circular hole, and along the diagonals and the hole, showing a preferred embodiment. According to an alternative embodiment, the element can comprise 12 or 16 grooves symmetrically distributed between the outer circumference of the element and the circular hole. Further, the element comprises a zone 22, which surrounds the circular hole and which is coated by a dark layer for increasing the ability to absorb heat in the zone in order to increase the formability of the element in this zone, as described below. For example, the zone can be coated by a layer of black color or a black foil layer.

The next step at the manufacturing of the device is to heat up the element 10 by radiation, conduction, convection, induction, or by combinations of these or by other means. For example, IR-lamps are used for the heating, which will give a desired temperature difference between the zone 22 surrounding the circular hole 20 and the remaining part of the element to increase the freedom to form said zone. The temperature of said zone having the dark layer is about 30 % higher after heating than the rest of the surface of the element.

Thereafter, the element is placed in a pressing tool (not shown), and a pressing force is applied to the first sheet 1 1 of metal foil for forming the sheets so that the bottom surface of the element obtains an inclination which corresponds to a correct slope toward the floor drain. Simultaneously, by effect from the pressing force, the edges of the circular hole are bent downwards forming a tubular part 44, which is intended to be connected to the floor drain 41, and the polymeric material flows out into the grooves of the first sheet in the zone 22 around the circular hole 20 and at the passage to the tubular part 44 close to the circular hole.

When the element 10 has been heated, a moderate pressing force can be used for forming the slope, which corresponds to the bottom surface of the device 40. Due to the grooves 21 of the first sheet 1 1, the polymeric material is allowed to flow out into said grooves. This provides a large freedom to form the element, especially in the zone 22 around the circular hole 20, which also contributes to keep the pressing force low and to reduce enclosed tensions of the element.

Finally, the produced device is cooled down while being in the pressing tool. During this step the foil sheets 1 1, 12 function as cooling flanges, which allow a short cooling cycle. The device 40 according to the procedure is now ready to be used for casting a slope toward a floor drain.

Fig 4 illustrates a method for casting a slope of a floor 43 toward a floor drain 41 by use of the device 40 produced according to the above described procedure.

The method comprises to provide the device 40 having a bottom surface 42, which corresponds to the inclination of the slope, and a tubular part 44 that is arranged at said bottom surface which is intended for connection with the floor drain. The device is connected to the floor drain by said tubular part. Levelling-screws 45 are provided and are arranged into the grooves at the outer circumference of the device, and through the polymer core and said second metal foil. Thereafter, the device 40 is horizontally aligned in relation to the floor 43, and the device is adjusted to the floor by means of the levelling-screws 45 to secure that its bottom surface 42 has and maintains a correct inclination toward the drain. The levelling- screws also provide a possibility to adapt the device to different floor materials to obtain a desired inclination toward the floor drain. Thereafter, floating putty 46 is supplied beneath the device so that the interspace between the bottom surface and the floor is filled. Finally, the level ling-screws are cut off and the device is removed when the floating putty has solidified.

Fig 5 shows that the inclination of the bottom surface of the device in relation to the floor is determined by a rate between a value A and a value B, where A is defined as the distance between the center of the floor drain to an outer point at the bottom surface of the device, and B is defined as the perpendicular distance between said outer point and the floor. For example, an ordinary Swedish construction standard is an inclination of 1 :50, which means that when A is 1000 mm the value of B should be 20 mm.

An advantage of the invention is that the size of the device ensures that a slope with correct inclination toward a floor drain can be produced without later manually adjustment of the slope, since the device covers the whole area around a drain and which shall include the slope.

A further advantage is that the device according to the invention provides a large flexibility at casting the slope toward a floor drain when these are not symmetrically arranged in a sanitary room or the like. It is easy to cut into the device for adapting it to drains which are placed close to a wall, and simultaneously maintain the stiffness of the device so that the inclination of the bottom surface is unchanged.

The benefits gained by the device described will increase the possibility to produce slopes according to approved standards in a repetitively and effective way, despite differences in the skills of the users of the device, which is a highly requested demand from both the construction business and the insurance companies for avoiding expensive complaints and damages.

The description above shall be considered as an exemplification of the principles of the invention and are not intended to limit the invention to the specific embodiments as illustrated. Other embodiments than the ones described can exist within the scope of protection, for example an alternative embodiment of the device can be produced by an element having another shape, such as rectangular, circular or polygonal.

In the claims, the term "comprise/comprising" does not exclude the presence of other elements or steps. Reference signs in the claims are provided as clarifying examples and shall not be construed as limiting the scope in any way.