Patent Description:
In the food industry it is important to mix food products together. Mixing processes in which granulate or powdered particles must be mixed together are often used. In practice it is often desirable to mix particles with differing agglomeration properties or to mix powdered particles with granulate particles, meaning mixing particles of solid material of various sizes.

In this, it is important that a mixed product is achieved with a good homogeneity and mixture ratio, and that no undesired agglomerates are added.

It is known to use a sieve to filter out the undesired particles out of the food products. This known technique has the disadvantage that it is a time consuming, and possibly manual, process. In particular, when this must be used with particles of various sizes.

<CIT> discloses a mixing device with a mixing chamber encompassing two inlet openings and two discharge ports.

The present invention and the preferred embodiments thereof have the goal of offering a solution for one or more of the disadvantages presented. One objective of the invention can therefore be to provide a mixing device of the aforementioned type that allows for the effective and efficient mixture of powdered particles with granulate particles.

This objective is achieved, according to the invention, with a mixing device that displays the technical characteristics of the independent claim <NUM>. The current invention is a mixing device for forming mixed powdered food products. In particular, the invention involves a mixing device with at least one vertical mixing body that rotates around an essentially vertical axis for mixing at least two types of powder.

In a first aspect of the invention, which may occur in combination with the other aspects and embodiments of the invention described herein, the invention comprises a mixing device for forming mixed powder containing a mixing chamber suitable for mixing powdered particles. The mixing chamber can have a minimum volume of <NUM> liters, preferably <NUM> liters, to be able to create large quantities in one batch.

The mixing chamber is equipped with at least one outlet opening to discharge mixed powder as well as two input openings at a distance from each other, in a top side of the mixing chamber, for separate addition of the powdered particles in the mixing chamber. There is a mixing assembly in the mixing chamber to generate at least one mixing zone, the mixing assembly encompassing preferably in each mixing zone one vertical mixing body that rotates around an essentially vertical axis for mixing at least two types of powder.

Both input openings are equipped with a first, finer sieve with smaller maximum sieve openings and a second, coarser sieve with larger maximum sieve openings respectively. Therefore, it is possible to introduce particles with different agglomeration properties in a time-efficient manner, such as simultaneously, without undesired agglomerates remaining in the sieve. Ultimately, a mixed product is achieved with a well-determined homogeneity and mix ratio.

A first embodiment, which can occur in combination with the other aspects and embodiments of the invention described herein, involves an aforementioned mixing device, wherein the maximum surface of the sieve openings of the first sieve falls between <NUM> and <NUM><NUM>, preferably about <NUM><NUM>.

A second embodiment, which can occur in combination with the other aspects and embodiments of the invention described herein, involves an aforementioned mixing device, wherein the maximum surface of the sieve openings of the second sieve falls between <NUM> and <NUM><NUM>, preferably about <NUM><NUM>.

A third embodiment, which can occur in combination with the other aspects and embodiments of the invention described herein, involves an aforementioned mixing device, wherein the first sieve is designed as a vibrating sieve and/or wherein the second sieve is designed as a vibrating sieve. In other embodiments, the first and/or second sieve may be designed as a rod sieve, a flat sieve, a rotating sieve, a shaking sieve, an oscillating sieve and a sieve that rocks back and forth.

A fourth embodiment, which can occur in combination with the other aspects and embodiments of the invention described herein, involves an aforementioned mixing device, wherein the input openings are designed as sunken openings that are consistent in shape and dimensions with the first and second sieves.

A fifth embodiment, which can occur in combination with the other aspects and embodiments of the invention described herein, involves an aforementioned mixing device, wherein the mixing chamber is designed to symmetrically rotate around a vertical axis. For example, the mixing chamber is designed as a cylinder with a figure-eight base surface.

A sixth embodiment, which can occur in combination with the other aspects and embodiments of the invention described herein, involves an aforementioned mixing device, wherein the mixing assembly is designed for the generation of two mixing zones in the mixing chamber, the assembly encompassing preferably two vertical mixing bodies for the generation of the two mixing zones that rotate respectively around essentially vertical axes for the mixing of at least two types of powders.

A seventh embodiment, which can occur in combination with the other aspects and embodiments of the invention described herein, involves an aforementioned mixing device, wherein each mixing body is designed as a ribbon mixer. The spiral shaped ribbon makes a three-dimensional mixture of various ingredients possible; a rotating, upward flow on the sides, as well as a downward flow in the middle. The embodiment is particularly suitable for the mixing of fragile products, such as in the food industry.

According to the invention, the vertical mixing body is designed for the generation of a first mixing zone and wherein the mixing assembly also has a horizontal mixing body for the generation of a second mixing zone, such as a side mixer as described in <CIT>.

A ninth embodiment, which can occur in combination with the other aspects and embodiments of the invention described herein, involves an aforementioned mixing device, wherein the horizontal mixing body is designed as a central axis or central tube equipped with at least one mixing device, wherein the at least one mixing device has a housing with a central opening that can be slid over the central axis or central tube and wherein the housing has at least one cutting element wherein the at least one cutting element welded seamlessly to the housing.

A tenth embodiment, which can occur in combination with the other aspects and embodiments of the invention described herein, involves an aforementioned mixing device, wherein in the mixing chamber there is at least one sprayer to spray a liquid in the second mixing zone.

An eleventh embodiment, which can occur in combination with the other aspects and embodiments of the invention described herein, involves an aforementioned mixing device, wherein the sprayer atomizes the liquid.

In a second aspect of the invention, which can occur in combination with the other aspects and embodiments of the invention described herein, the invention involves a method for forming a mixed powder for food products encompassing the steps of the provision of an aforementioned mixing device; the simultaneous addition of first and second powdered particles via the first and second input openings respectively into a mixing chamber of the mixing device; and the mixing of the first and second powdered particles in the mixing chamber. In a preferred embodiment, the mixing chamber has a fill level of at least <NUM>% after the powdered particles are added.

The invention will be explained in more detail using an example embodiment shown in the figure.

<FIG> shows an openwork view of a simplified representation of a mixing device according to one embodiment of the present invention.

The current invention will be described with regard to certain embodiments and with reference to certain drawings, but the invention is not limited to these and is only determined by the claims. The figures described are only schematic and non-limiting. In the figures, the size of certain element may be exaggerated and not drawn to scale for illustrative purposes. The dimensions and the relative dimensions are not necessarily consistent with actual practical designs of the invention.

In addition, terms such as "first, "second, "third" and the like in the descriptions and in the claims are used to differentiate between comparable elements are not necessarily to describe a sequential or chronological order. The terms are interchangeable under suitable circumstances and the embodiments of the invention may be applied in sequences other than those described or illustrated here.

In addition, the terms, top, bottom, over, under and the like in the description and claims are used for illustrative purposes and not necessarily to describe relative positions. The terms used are interchangeable under fitting circumstances and the embodiments of the invention described can be applied in other orientations than described or illustrated here.

Furthermore, the various embodiments, even though called "preferred designs" must be considered rather as a manner of example of how the invention can be designed than as a limitation of the range of the invention.

The term "encompassing", used in the claims, must not be interpreted as being limited to the resources or steps listed after it. The term does not exclude other elements or steps. The term should be interpreted as specifying for the presence of the listed features, elements, steps or components which are referenced, but does not exclude the presence or addition of one or more other features, elements, steps or components or groups thereof. The range of the expression "a design encompassing resources A and B" must thus not be limited to designs that consist only of A and B.

The systems represented in the figures are mixing devices, or elements for these, for the mixing of a first and second powder.

<FIG> shows a mixing device <NUM> for creating a mixed powder from a first and a second powder encompassing a cylindrical mixing chamber <NUM> suitable for receiving the first and second powders. The mixing chamber has two input openings <NUM>, <NUM> in a top surface at a distance from each other for the respective addition of the first and second powders. The mixing chamber also has multiple ribbon shaped mixing bodies <NUM>, <NUM> for mixing the additive powders. On the bottom of the mixing chamber <NUM> there are one or more discharge openings <NUM> for discharging the mixed powder.

A first of the input openings <NUM> has a first cylindrical sub-chamber <NUM> of the mixing chamber <NUM> and is designed for the addition of the first powder into the first sub-chamber <NUM> via a first, finer sieve <NUM> with smaller maximal sieve openings. A second input opening <NUM> is provided in a second cylindrical sub-chamber <NUM> of the mixing chamber <NUM> and is designed for the addition of the second powder into the second sub-chamber <NUM> via a second, coarser sieve <NUM> with larger maximal sieve openings.

The first of the ribbon-shaped mixing bodies <NUM> is located in the first cylindrical sub-chamber and extends vertically between the top surface <NUM> and the bottom surface <NUM>. The second of the mixing bodies <NUM> is located in the second cylindrical sub-chamber <NUM> and extends vertically between the top surface <NUM> and the bottom surface <NUM>. Both mixing bodies <NUM>, <NUM> are designed to rotate around an essentially central, vertical axis of the respective sub-chamber <NUM>, <NUM> to mix the added powders together.

Claim 1:
Mixing device for forming mixed powders for food products encompassing a mixing chamber (<NUM>) suitable for mixing powdered particles, the mixing chamber containing at least one discharge opening (<NUM>) for discharging mixed powder, as well two input openings (<NUM>, <NUM>) at a distance from each other in a top side of the mixing chamber for the separate addition of powdered particles into the mixing chamber.
wherein there is a mixing assembly in the mixing chamber to generate at least one mixing zone, the mixing assembly encompassing preferably in each mixing zone one vertical mixing body (<NUM>; <NUM>) that rotates around an essentially vertical axis for mixing at least two types of powder,
wherein both input openings (<NUM>, <NUM>) are respectively covered with a first, finer sieve (<NUM>) with smaller maximum sieve openings and a second, coarser sieve (<NUM>) with larger maximum sieve openings respectively, wherein the vertical mixing body (<NUM>; <NUM>) is designed for the generation of a first mixing zone and wherein the mixing assembly also has a horizontal mixing body (<NUM>; <NUM>) for generating a second mixing zone.