Field of the Invention

The present invention relates to a mechanism which ensures that the shadow of an umbrella that is under the sun always falls on an area comprising the same fixed point.

In particular, the present invention relates to a mechanism with two degrees of freedom which allows an umbrella to move on a spherical surface.

Background of the Invention

The position of the shadow on the ground created by a fixed umbrella that is directly exposed to sunlight changes constantly due to the movement of the sun in the sky. This situation leads to the need of regularly moving an object (for example a sunbed) that is intended to be kept in shade to wherever the shade is. It is possible to solve this problem by having the umbrella follow the sun by means of a mechanism that has at least two degrees of freedom.

One of the simplest solutions to provide an umbrella with the ability to track the sun is described in patent document no US3044478. In this design, the umbrella can be rotated by hand about an axis perpendicular to its pole and therefore a mechanism with two degrees of freedom is achieved by including the natural rotation ability about the pole. The application of this logic with the automatic control principle is the subject matter of the patent document no US 10250817. In such a mechanism, since the elevation angle of the umbrella is changed by tilting the umbrella pole via a hinge, the useful volume just below the umbrella decreases as the umbrella approaches the ground. European patent no EP3039986A1 discloses a design with a multi-degree of freedom that allows the umbrella to be fixed in different positions. Here, the umbrella is located next to the pole, not on top of it. The connection of these two elements is provided by the slider-crank mechanism, and the fact that the umbrella is highly adjustable causes complexity.

A design in which the pole is in the form of a partial circle and the umbrella can slide on the pole can be found at: “http://web.archive.org/web/202002292026 /https ://fiberbuiltumbrellas.com/wp-content/uploads/2018/09/Bali. pdf’. The second degree of freedom is achieved with the rotation of the pole about the vertical axis of the ground.

Even though the abovementioned umbrella designs provide a certain authority over the position of the shadow, they are not capable of meeting the need for the shadow to always fall on the same fixed point.

Objective of the Invention

The objective of the present invention is to provide an umbrella system which will always project the shadow on an area comprising the same fixed point regardless of the position of the sun in the sky.

Another objective of the present invention is to provide an umbrella system which does not reduce the useful volume under it while tracking the sun.

Description of the Figures

Figure 1 is an isometric view of the spherical mechanism according to the present invention with an umbrella attached thereon, shown in dashed lines since it is not a part of the invention. Figure 2a is an isometric view of the spherical mechanism.

Figure 2b is a side view of the spherical mechanism.

Figure 3 is a view of sliding part with a handle which can be attached to it when the spherical mechanism is operated by muscle force.

Figure 4a is an isometric view comprising an example solution of an alternative configuration of the spherical mechanism in which the rotating part can be folded over the pole.

Figure 4b is a side view of the alternative configuration of the spherical mechanism in which the rotating part can be folded over the pole, showing the rotating part folded on the pole.

Description of the References in the Figures

1: Pole

2: Rotating part 3: Sliding part

Description of the Invention

In this detailed description, the preferred embodiments of the spherical mechanism of the present invention are described only to facilitate better understanding of the invention without creating any limiting effect.

In order to turn to the sun from a point on the earth, one should utilize appropriate azimuth and elevation angles. The mechanism of the present invention provides these two angular degrees of freedom and always projects the shadow of an umbrella attached thereto onto an area which will always comprise the same fixed point.

The spherical mechanism of the present invention, in its most general form, comprises - a pole (1);

- a rotating part (2) which is connected to the pole (1) with a revolute joint,

- a sliding part (3) which moves along a circular path on the rotating part (2).

The pole (1) is fixed to the ground and bears the weight of the system. The rotating part (2) is connected to the pole (1) by a revolute joint located at the top portion of the pole (1). By means of this joint, the rotating part (2) has the ability to rotate while remaining parallel to the ground. The sliding part (3) connected to the rotating part (2) has the ability to move on the rotating part (2) by making circular motion. For this purpose; both the sliding part (3) and the relevant part of the rotating part (2) on which it moves have a partial circular profile in terms of general structure. The said rotating and moving abilities enable the sliding part (3), which has a mechanical interface thereon required for mounting the useful load, to travel on a spherical surface. This allows the adjustment of the azimuth and elevation angles of the mechanism, and thus the tracking of the sun.

The spherical mechanism of the present invention can be moved by muscle power or motor power. In case the mechanism is moved by muscle power, a handle can be added to the sliding part (3) as shown in Figure 3.

For reasons such as packageability concerns and/or to prevent bad weather from damaging the system, an alternative mechanism configuration in which the rotating part (2) folds on the pole (1) may be preferred. An example solution for this requirement is presented in Figure 4.

While the spherical mechanism may comprise a lock mechanism which enables the sliding part (3) to be fixed on the rotating part (2), it may also comprise a lock mechanism which enables the rotating part (2) to be fixed on the pole (1). The Industrial Applicability of the Invention

It is possible to realize the above-mentioned spherical mechanism with common mechanical production techniques. The resulting umbrella system can be used to obtain effective sun protection in places such as parks, gardens, beaches and balconies.