The invention relates to a method for closing a hole, such as a mounting hole, which is constructed with a circular opening that is located in a surface and which contains a mounting member such as a screw, pointed screw or threaded bolt at the bottom of the hole, and wherein the surface forms part of a system that is located in an environment that places special requirements on hygiene.

Furthermore, the invention relates to the use of the described method.

There are several known methods for closing holes such as mounting holes extending from the surface of a product. It could for example be desirable to close the holes for hygienic reasons, so that no impurities and / or bacteria can accumulate in the holes.

Several known methods for closing holes include the use of plugs, including, for example, plugs formed with barbs, which are inserted into the holes to be closed.

However, it has been shown that the previously known methods for closing holes cannot meet the hygiene requirements of standards such as the so- called 3A and EHEDG.

The disadvantages of the currently know methods that employ plugs for closing holes include the fact that the plugs, not least over time, cannot effectively prevent all impurities and / or bacteria from entering into the holes, for example in connection with the use of liquid cleaners.

It is therefore an object of the invention to provide a method without the above disadvantages.

The object of the invention is achieved by a method of the type described in the introduction to claim 1 which is characterised in that a hole is closed by an elastic ball that is pressed into the hole through the circular opening, where the inside of the hole is shaped as part of a sphere having a diameter which is larger than the diameter of the hole's circular opening, and which is equal to or less than the diameter of the ball.

This way, it becomes possible to achieve effective closure of a hole, as the elastic ball will press against the hole's inner spherical surface, thus ensuring that the closure of the hole remains effective - also over time.

Other preferred embodiments of the method are described in claims 2 through 6.

As mentioned, the invention also includes the use of the above described method for closing holes in systems and applications that place special demands on hygiene and clean design as specified by the so-called 3A and EHEDG standards.

This makes it possible to manufacture products which include holes to be closed, which meet the hygiene requirements for the most demanding standards.

Additional applications are described in claim 8.

The invention will now be further explained with reference to the drawings, in which:

Fig. 1 shows a product depicted in perspective which comprises a cylinderlike device that surrounds a shaft, where the mounting holes in the cylinderlike device are closed with the elastic balls.

Fig. 2 shows the same product as Fig. 1 but from another perspective.

Fig. 3 shows the same product as Fig. 1 and 2 but as a sectional view.

Fig. 4 shows a section of Fig. 3 which comprises a contact surface between the product and an elastic ball.

Fig. 5 shows another section of Fig. 3 which comprises the placement of an elastic ball in a hole in a product, whereby the ball closes the hole.

Fig. 6 shows a sectional view in perspective of the same configuration as depicted in Fig. 5.

Fig. 7 shows a perspective view of a traversed hole that can be closed by an elastic ball.

Fig. 8 shows a sectional view of a ball inserted for closing a hole which at the bottom is fitted with a mounting member such as a threaded bolt with a cavity between the ball and the mounting member.

Fig. 1 shows a product that comprises a cylinder-like device (2,3,4) which encloses a shaft (1) wherein mounting holes (5,7,9) in the cylinder-like device (2,3,4) are closed with elastic balls (6,8,10).

The product is also depicted in Fig. 2, seen from an end that is perpendicular to the product's longitudinal axis, and wherein a sectional A-A axis is plotted.

Fig. 3 depicts the sectional A-A axis shown in Fig. 2. Fig. 3 shows that the product's cylinder-like device (2,3,4) is constructed with semi-spherical holes that are filled with balls (6,8,10) which are elastic.

Threaded screws (11) are placed below the elastic balls (6,8,10) which are used for mounting of the shaft (1) that is enclosed by the cylinder-like device (2,3,4).

Fig. 3 contains graphical definition of two detail areas B and C.

Fig. 4 depicts an enlarged view of the detail area B from Fig. 3, comprising a circular cross-section of the contact surface between an elastic ball (8) and the surface of the corresponding product part (3) from which it appears that the edge (14) of the opening on the hole, in which the ball (8) is located, is rounded. It is also shown that the surface (13) located between the rounded edge (14) and the product's surface part (3) is constructed as a truncated cone.

Practical tests have shown that the disclosed details B, C, which include the rounded edge (14) and the truncated cone surface (13) have a significant impact on the method which comprises introducing an elastic ball (8) into a semi-spherical hole to be closed by the elastic ball (8).

The details described ensure that an elastic ball can be easily squeezed into a semi-spherical hole to be closed by the elastic ball, without the ball being damaged during insertion.

Fig. 5 shows an enlarged view of detail C from Fig. 3 which comprises an elastic ball (6) that is located in a semi-spherical hole with opening to the surface of a product part (2).

A threaded bolt (11) is located below the ball (6). This is used to fasten a shaft (1) relative to the product part (2).

As will be apparent from Fig. 5, the circular opening of the hole in which the ball (6) is located, has a diameter (15) which is smaller than the inner diameter (16) of the semi-spherical hole in which the ball (6) is located.

It is also a special feature of the method that the inner diameter (16) of the semi-spherical hole in which the ball (6) is located, is equal to or less than the ball's (8) diameter (19). This ensures that the ball (6) by virtue of its elasticity, independently of time, will press against the hole's inner part of its spherical surfaces in which the ball (6) is located, whereby the hole becomes effectively closed. Fig. 6 shows the same detail section C as Fig. 5, but depicted in perspective.

Fig. 7 depicts a cross-section of a semi-spherical hole that can be closed with an elastic ball, wherein the hole comprises a ball member (17) and a threaded member (12), and wherein the surface (18) of the ball member (17) is polished.

Fig. 8 shows a preferred embodiment of the invention, where a ball (6) is located in a hole and the underlying mounting member such as a threaded bolt (11 ) is placed in a cavity (20).

This ensures that the cavity (20), which will normally be filled with atmospheric air, will have a resilient effect, which results in the ball (6) in the event of an action of an external force, such as from a finger, will be resilient and thus difficult to remove from the hole without the use of a tool.

From figures 1 to 8 and the accompanying description it can thus be summarised that the method of the invention is characterised in that: · a hole is closed by an elastic ball (6,8,10) which is pressed into the hole through the circular opening (5,7,9), where the inside of the hole is formed as part of a sphere having a diameter (16) which is larger than the diameter of the hole's circular opening (15) and which is equal to or less than the diameter of the ball (19).

• the edge (14) of the hole's circular opening (5,7,9) is rounded. • a truncated cone surface (13) is present between the edge (14) of the hole's circular opening (5,7,9) and the surface (2,3,4). · there is a cavity (20) between an inserted ball (6,8,10) and a mounting member such as a threaded bolt (11).

It is a furthermore a special characteristic of the method that: · balls (6,8,10) for closing the holes are constructed in whole or in part of a polymeric material, which cam for example optimise the balls' elasticity.

• balls (6,8,10) for closing the holes can be produced in different colours, thus enabling the balls to be colour-coded balls.

As mentioned, the invention also includes the use of the above described method for closing holes in systems and applications that place special demands on hygiene and clean design as specified by the so-called 3A and EHEDG standards.

The application includes facilities for manufacturing of food and beverages and installations for the manufacture of drugs including medicines and for facilities for the treatment of humans and animals, including hospitals.