The present invention relates to an improved centrifuge, particularly for drying vegetable products.

In the food industry, it is often necessary drying vegetable products, such as spinach or lettuce, from the water used to wash them before packaging. To accomplish this drying, they are generally used to centrifuges. The centrifuges are machines comprising an inner rotor inserted into an external stator, both having cylindrical shape. A cavity is located between stator and rotor for collecting and conveying the water to the drain.

The inner rotor is hollow, and has a plurality of holes on its lateral surface, said holes do not allow the passage of vegetable products, but allow water to flow towards the cavity.

The operation of a conventional centrifuge is as follows: the vegetable products, washed and optionally cut, are loaded into the inner rotor, which is subjected to rotation. The vegetable products, due to the centrifugal force, impact on the inner lateral surface of the rotor; water passes through the holes due to the centrifugal force, reaches the cavity between the rotor and the stator and is conveyed in appropriate outflow tubes provided in the lower part of the centrifuge.

Centrifuges of this type currently available on the market have several drawbacks.

Particularly, they are characterized by a low drying efficiency, so that, at the end of the process, loaded vegetable products are not sufficiently dried, otherwise the drying process requires too much time.

Additionally, when hard vegetables are subjected to processing, their impact against the inner surface of the rotor during the rotation and can deform the same rotor.

In the light of the above, object of the present invention is to provide an improved centrifuge, particularly for drying vegetable products, able to overcome the drawbacks of prior art solutions.

It is therefore specific object of the present invention an improved centrifuge, in particular for drying vegetable products, comprising:

- at least one hollow stator, having a vertical axis, and a lateral wall and a lower statoric base,

- at least one hollow rotor, internally coaxial with respect to said stator and providing a perforated lateral wall, and a lower rotoric base,

said centrifuge being characterized in that it by comprises a plurality of lateral fins arranged externally on said rigid lateral wall of said rotor, inclined at a set angle comprised between 15° and 60° with respect to said vertical axis, and in that a space open at the top by an opening is provided between the side wall of said rotor and the side wall of said stator.

Preferably, said set inclination angle of said lateral fins with respect to said vertical axis is about 30°.

Preferably, said rotor includes a plurality of bottom fins, disposed radially on said lower rotoric base, in correspondence of, integral or not, said lateral fins.

Preferably, said rotor includes an upper closure element.

Preferably, said lower statoric base comprises at least one channel for the water outflow.

Preferably, said lower base is inclined from the center towards the outside. Preferably, said stator provides a partial lateral closure, arranged in correspondence of said opening.

Preferably, said centrifuge is hinged around a tilting axis substantially perpendicular to said vertical axis, to allow the expulsion from said centrifuge of the dried vegetable products.

The present invention will be described, for illustrative, but not limitative, purposes, according to a preferred embodiment, with reference to the enclosed figures, wherein:

figure 1 is a section view, according to a plane passing through the axis of rotation of a centrifuge according to the invention; and

figures 2-4 are perspective views of an element of an improved centrifuge according to the invention.

Making reference to the figures, an improved centrifuge is shown, particularly to dry vegetable products, generally indicated by the reference number 100.

Centrifuge 100 provides a rotor 1 and a stator 2, which in a preferred embodiment are cylindrical. The stator 2 includes lower channels 3 for outflow of the water, and a central cavity 4, inside which the rotor 1 is housed, so that the rotor 1 axis of rotation 5 is coincident with the symmetry axis of the stator 2.

Rotor 1 provides a central cavity 6, for loading the vegetables to be dried, and a plurality of holes 7 along the lateral wall 8, to allow the passage of water. Rotor 1 is connected to a motor unit (not shown) through a drive shaft 9.

According to the present invention, the rotor 1 comprises a plurality of lateral fins 10, of rigid material, which are arranged along the outer lateral wall 8 of the rotor 1 , and inclined at an angle between 15° and 60°, preferably about 30°, with respect to the rotation axis 5 of the rotor 1. Further, rotor 1 and stator 2 are coupled in such a way that between the two there is a space 11 , open at the top with respect to the statoric base 12 of the stator 2.

The operation of the centrifuge 100 is as follows: if it is wished drying the vegetable products from water used for their washing, they are loaded into the cavity 6 of the rotor 1. Thereafter, the motor unit is activated, rotating the rotor 1 around to its rotation axis 5. Vegetables are pushed by the centrifugal force along the inner surface of the lateral wall 8, loosing some water, which passes through the holes 7 and ends up in the cavity 11 under the thrust of the centrifugal force, for flowing then into the outflow channels 3. The rotation of the rotor 1 causes the side flaps 10, being inclined, thus behaving like a propeller, causing a vortex in the cavity 11 , open at the top. On one hand, this vortex increases the ventilation of the vegetable products placed into the rotor 1 promoting, or speeding, their drying. The vortex also creates a sort of suction effect, or a depression, towards the area between the rotoric base 13 and the statoric base 12, through the transfer of the water extracted from the vegetables in outflow channels 3, thus facilitating the evacuation. Additionally, the presence of the side flaps 10 makes it more resistant the lateral wall 8 to shocks caused by hard plant products, such as for example the core salad.

Making reference to figure 1 , the stator 2 includes a partial lateral closure 14, located at the distal end with respect to its statoric 12. Advantageously, in this way it is avoided that the water extracted from the vegetable products can splash from an upper opening 15, having an annular shape, communicating with the space 11.

Making reference to figure 1 , stator 12 of the statoric base 2 is inclined from the centre towards the outside. Advantageously, in this way the water extracted from the vegetable products are conveyed towards the outflow channels 3.

Making reference to figures 1 , 3 and 4, the rotor 1 provides lower fins 16, placed radially on its rotoric base 13. Advantageously, in this way the rotor is more resistant to impact with hard vegetable products.

Making reference to figure 1 , rotor 1 provides an upper closure element 17. Advantageously, in this way it is prevented the exit of vegetable products from the rotor 1 during its rotation.

Furthermore, as shown in figure 1 , stator 2 is rotatively connected to two lateral opposite supports 18a, 18b, in such a way to allow the ejection of the vegetable products at the end of the drying process, by means of tilting of the centrifuge 100 around a tilting axis A orthogonal with respect to the rotation axis 5.

The present invention has been described, for illustrative but not limitative purposes, according to its preferred embodiments, but it is to be understood that variations and/or modifications may be introduced by those skilled in the art without departing from the scope as defined by the appended claims.