The subject of the invention relates to a unit for the production of volume-increased, scoop-dispensed ice cream preparation at a ready temperature of under -4 °C, which has mixing vessel with a delimiting wall surrounding the work space suitable for accommodating the ice cream preparation and a mixing body fitted with blades and located in the mixing vessel so that it may rotate, the mixing vessel's wall is supplied with at least one transfer opening serving to place the ingredients used for the production of the ice cream preparation into the work space of the mixing vessel and to remove the ready ice cream preparation from the work space, and the transfer opening is sealed with a removable cover, and the wall of the mixing vessel and/or the cover is supplemented with a gas-feed pipe end that has a dispensing channel suitable for placing the gas phase ingredients also required for the production of the volume-increased ice cream preparation into the work space of the mixing vessel.

The present invention also relates to a procedure for the production of volume- increased ice cream preparation, during which a prepared ice cream base is placed in the work space of the mixing vessel and there it is subjected to mixing with the help of the mixing body.

One of the well-known summer cooling desserts is ice cream, of which several, various forms are in existence. Scooped ice creams served in a cone belong to one of these groups. Equipment has been used for preparing such ice cream for a long time, the essence of which is that the liquid and/or coarse, granular basic materials are placed in a vessel where the liquid and solid phase ingredients may be homogenised by mixing, then the basic ice cream mixture produced in this way may be frozen, finally the frozen ice cream preparation may be removed from the vessel and offered for sale. A device serving for placing the basic ingredients of ice cream into a freezer vessel is presented, by e.g. patent specification registration number GB 1.062.517, the essence of which is that the liquid basic materials are transferred to the work space with the help of a part-unit regulated with a pressure sensor, where the pressure sensor monitors the pressure value in the work space and depending on this value it transfers the next amount of basic material to be frozen into the work space. While patent specification registration number GB 1.114.072 presents a solution that makes it possible to keep the ice cream preparation device clean with the help of over-pressure.

Patent specification registration number US 4.659.575 relates to a structure in the case of which gases are placed in the work space to increase the basic creaminess of the ice cream, and it endeavours to mix these gases among the particles of the basic material to as great an extent as possible. The essence of the solution is that the gas gets into the work space via the base of the mixing vessel and the gas passing through the material mixture and collected in the free upper part of the mixing vessel is transferred from the upper part of the mixing vessel via a pipe and then returned to the lower part of the vessel to be passed through the material mixture once again.

The disadvantage of the solution, however, is that returning the gas passing through the mixture and not capable of being absorbed and its repeated mixing is energy and time-consuming, it efficiency is inappropriate, therefore the creaminess of the ice cream preparation can only be improved within certain limits.

A further disadvantage of the solution is that the feeding of the mixed gas that is desired to be absorbed by returning it does not make it possible to always have the desired amount of gas absorbed into the material mixture which is required for achieving the appropriate degree of creaminess, in this way the physical characteristics of the ready ice cream preparation will not be consistent, which may be unfavourable with respect to sales due to the quality differences between the individual ice cream batches. Our aim with the solution according to the invention was to overcome the deficiencies of the known equipment suitable for the preparation of scoop-served ice creams and to create a production unit that makes it possible to maintain the amount of gas state medium absorbed in the ice cream preparation at a continuous value, to mix in the given amount of gas quickly, evenly and in an energy-efficient way, and to ensure that the ice cream preparation can be appropriately foamed up with this absorbed gas, i.e. so that the volume of the ice cream preparation may be sufficiently increased with the given amount of gas.

The recognition that led to the creation of the unit according to the invention was that if work space of the unit serving as the location of the mixing is created in an unusual way as a pressure vessel and if the amount of gas desired to be absorbed is introduced into the work space in a novel way, and the gas in the work space is worked together with the basic preparation in a way different to that known of, then the given amount of gas may be reliably absorbed into the basic material of the ice cream preparation and in this way the task may be solved.

In accordance with the set aim the unit according to the invention for the production of volume-increased, scoop-dispensed ice cream preparation at a ready temperature of under -4 °C, which has mixing vessel with a delimiting wall surrounding the work space suitable for accommodating the ice cream preparation and a mixing body fitted with blades and located in the mixing vessel so that it may rotate, the mixing vessel's wall is supplied with at least one transfer opening serving to place the ingredients used for the production of the ice cream preparation into the work space of the mixing vessel and to remove the ready ice cream preparation from the work space, and the transfer opening is sealed with a removable cover, and the wall of the mixing vessel and/or the cover is supplemented with a gas-feed pipe end that has a dispensing channel suitable for placing the gas phase ingredients also required for the production of the volume-increased ice cream preparation into the work space of the mixing vessel - is set up in such a way that the mixing vessel is constructed as a pressure vessel suitable for withstanding at least 1.2 bar, the cover is fixed to the mixing vessel sealing the transfer opening with a gas- tight seal suitable for retaining the pressure in the work space, and the gas-feed pipe end is connected to the mixing vessel in a way suitable for receiving a gas phase medium at least 1.2 bar and for transferring it into the mixing vessel.

A further feature of the unit according to the invention may be that the mixing vessel, and the gas-tight seal between the cover sealing the transfer opening of the mixing vessel and the mixing vessel is established to be suitable for withstanding an internal pressure of at least 4 bar, and the gas-feed pipe is suitable for receiving and forwarding a gas state medium at a pressure of at least 4 bar.

In the case of another version of the invention, two transfer openings are created in the wall of the mixing vessel, and each of the two transfer openings is sealed with a cover, the individual covers and the wall of the mixing vessel are connected to each other with a gas-tight seal.

In the case of yet another different structure of the unit the gas-feed pipe end is fitted with a sealing body, furthermore, in a given case a device limiting the flow direction, e.g. a flap valve is connected to the gas-feed pipe end and a pressure-regulating device is connected to the gas-feed pipe end.

In the case of another different embodiment of the invention the gas-tight seal is formed by a shaped profile sealing element inserted between the mixing vessel and the cover.

In the case of a further embodiment of the unit at least a part of the external edge delimiting the blade of the mixing body is in contact with the internal side of the delimiting wall of the work space, or the external edge delimiting the blade of the mixing body is separated from the internal side of the delimiting wall of the work space by a gap. From the point of view of the invention it may be preferable if the mixing vessel is coupled with a heat exchanger suitable for cooling the work space, and the heat exchanger is located on the external side of the wall of the mixing vessel.

In the case of yet another different version of the unit, the unit is installed in an ice cream making machine known of in itself and suitable for producing scoop-served ice cream.

In accordance with the set aim the procedure for the production of volume-increased ice cream preparation, - during which a prepared ice cream base is placed in the work space of the mixing vessel and there it is subjected to mixing with the help of the mixing body, - based on the principle that after placing the prepared ice cream base into the work space, the work space is hermetically sealed with a gas-tight seal, then a gas phase medium at a pressure of at least 1.2 bar is fed into the work space via the feed channel of the gas-feed pipe end, and the gas phase medium and the particles of the ice cream base are mixed with the help of the mixing body, and in this way at least a part of the gas phase medium is absorbed by being distributed among the particles of the ice cream base, and so the volume-increased ice cream preparation is produced in this way.

A further feature of the procedure according to the invention may be that the prepared ice cream base is placed into the work space of the mixing vessel in a crushed form at a temperature of under at least -10 °C.

The other version of the procedure according to the invention may be that the prepared ice cream base is placed into the work space of the mixing vessel in the liquid phase and is cooled there to a temperature of at least -4 °C whilst being mixed. In this case the feeding of the gas phase medium into the work space is only started after cooling down the prepared ice cream base to a temperature of -4 °C.

The further possible version of the procedure according to the invention is that the gas phase medium is fed into the work space of the mixing vessel at a pressure of at least 4 bar. In another possible version of the procedure according to the invention, before feeding the gas phase medium into the work space the pressure in the work space is reduced.

The further possible version of the procedure according to the invention is that the feeding of the gas phase medium into the work space and the mixing of the ice cream base are performed in parallel.

In another possible version of the procedure according to the invention, the work space of the mixing vessel is only half filled with the prepared ice cream base.

The unit and the procedure according to the invention has numerous advantageous characteristics. The most important of these is that due to the mixing vessel being established as a pressure vessel and due to the gas-feed pipe end set up so as to be able to insert the amount of gas desired to be absorbed into the mixing vessel in one batch, the given amount of ice cream preparation may be evenly mixed with the desired amount of gas simply, quickly and with a favourable amount of energy investment and so economically producing an ice cream preparation creating a creamy sensation.

Another feature that must be viewed as an advantage is that due to the novel mixing vessel and gas feed a greater volume, i.e. visually more, of ice cream preparation may be produced from a given amount of basic material as a result of the more effective mixing of the gas, i.e. due to the greater amount of gas being absorbed, which has a favourable effect on sales revenue. As an ice cream ball of the same weight has greater physical dimensions and so promises Ά more favourable investment for the purchaser, which results in better saleability of the volume-increased ice cream preparation.

Another feature that may be listed among the advantages is that by using the unit according to the invention volume-increased ice cream preparation may also be produced without a foaming additive, which reduces the costs even further. It may also be viewed as an advantage that due to the novel unit it is sufficient to perform the flavouring of the basic ice cream simultaneously with the volume increase, therefore it is not necessary to separately produce various flavours of ice cream base, which represents a large step forwards from the point of view of business organisation, as it is sufficient to prepare the two main ice cream bases - water-based and milk-based - in a larger quantity, and the flavouring may be performed depending on turnover directly in the volume-increasing phase with the help of the unit according to the invention. This advantage may result in a reduction of warehousing and chiller capacity, which may further reduce the operation costs of an ice cream sales unit.

In the case of a unit according to the invention where the ice cream base does not have to be chilled and so the blades of the mixing body do not come into contact with the internal side of the wall of the mixing vessel, the blades do not get worn.

It is also important to highlight that the unit according to the invention is also capable of producing ice cream by itself - by leaving out the ice cream making machine - if the pre-frozen base liquid ground using an ice grinder is placed in the mixing vessel and ice cream is made from this. Therefore, the ice cream production process becomes more economical.

Another feature that may be mentioned among the advantages is that the unit according to the invention may also be fitted into a traditional ice cream making machine, and so the specific capacity of these devices may also be improved.

The unit according to the invention is presented henceforward in more detail on the basis of drawings in connection with construction embodiments. In the drawing

Figure 1 shows a possible version of the unit according to the invention in side view, in partial cross-section,

Figure 2 shows a different embodiment of the unit according to the invention in side view, in partial cross-section. Figure 1 depicts a version of the unit 1 according to the invention in the case of which the work space 12 delimited by the wall 1 1 of the mixing vessel 10 is not chilled, therefore in the case of this embodiment the ice cream base consisting of the already frozen and crushed granular particles or even the ready ice cream waiting for volume- increasing processing maybe placed in the work space 12.

The mixing body 30 with blades 31 is located in the work space 12 delimited by the wall 1 1 of the mixing vessel 10, which mixing body 30 - in this case - carries four blades 31 and is connected to the base of the mixing vessel 10 with a gas-tight seat in such a way that the torque-receiving body 32 of the mixing body 30 is on the external side l ib of the wall 11 of the mixing vessel 10. The torque-receiving body 32 makes it possible to enable the mixing body 30 to be rotated, and in this way the blades 31 move around and around in the work space 12 of the mixing vessel 10 around the mixing body 30. It may be observed that in the case of the given embodiment the external edges 31a of the blades 31 do not come into contact with the internal side 11 a of the wall 11 of the mixing vessel 10, instead they are separated from it by a gap "T" with a size of 0.5-1 mm. From this point of view it is preferable that in this way the blades 31 essentially do not get worn during the mixing of the ice cream base. It may also be observed that the blades 31 are supplied with openings 31b, which make it possible to more intensively and effectively mix the ice cream preparation in the work space 12 of the mixing vessel 10, and so have the gas inserted into the work space 12 more evenly absorbed.

Figure 1 also shows that the wall 1 1 of the mixing vessel 10 encloses the transfer opening 13, which transfer opening 13, in the case of this embodiment, is the only opening through which the ice cream base may be placed into the work space 12 of the mixing vessel 10 and through which the ready volume-increased ice cream preparation may be removed from the work space 12.

The transfer opening 13 is sealed with a cover 20, and in such a way that between the edge of the wall 11 of the mixing vessel 10 enclosing the transfer opening 13 and the cover 20 there is a gas-tight seal 40, in this case a profile sealing element 41. With this sealing element 41 an air-tight seal may be ensured between the mixing vessel 10 and the cover 20 up to a pressure of 4.2 bar, therefore a pressure of 4 bar may be created in the work space 12 of the mixing vessel 10 without any loss of pressure occurring. In order to withstand the large pressure the gas-tight seal 40, apart from the sealing element 41, also contains a sealing structure 42, the task of which is to force the cover 20 up against the sealing element 41 located at the transfer opening of the mixing vessel 10 to the appropriate extent.

The unit 1 also includes a gas-feed pipe end 15, as well as - in this case - a gas- extraction pipe end 16, which are fixed into the wall 1 1 of the mixing vessel 10, e.g. by welding. The gas-feed pipe end 15 has a feed channel 15 a, which opens into the work space 12 of the mixing vessel 10, and makes it possible to insert high-pressure, e.g. 4- bar gas into the work space 12. The gas-extraction pipe end 16 may serve to reduce the pressure of the work space 12 of the mixing vessel 10.

Preferably a closing body 15b may be placed on the part of the gas-feed pipe end 15 distant from the mixing vessel 10, which opens or closes the pathway of the gas in the feed channel 15a of the gas-feed pipe end 15. It is also preferable if the closing body 15b is coupled with a flow-direction limiting structure 50, which in this case is a flap valve 51. This flow-direction limiting structure 50 ensures that no pressure drop occurs from the work space 12 of the mixing vessel 10 through the feed channel 15a of the gas-feed pipe end 15 even if the own pressure of the gas to be introduced were to drop under the pressure existing in the work space 12 of the mixing vessel 10.

The use of the unit 1 according to figure 1 according to the procedure takes place in the following way. First of all the ice cream base frozen and formed into a block using a technology procedure known of in itself must be crushed and made into a granulate. This granulate may be filled into the work space 12 of the mixing vessel 10 through the transfer opening 13 of the unit 1 in such a way that it only fills a part of the work space 12, preferably approximately half of it, as during the absorption of the gas the volume of the ice cream base increases significantly as a consequence of the absorbed gas. Following this with the sealing element 41 of the gas-tight seal 40 is placed on the edge of the wall 11 of the mixing vessel 10 surrounding the transfer opening 13 and then by placing the cover 20 on it the cover 20 may be forced up against the wall 11 of the mixing vessel 10 with the help of the sealing structure 42 of the gas-tight seal 40. After sealing the transfer opening 13 of the mixing vessel 10 torque is transmitted with the torque receiving body 32 of the mixing body 30 so making the mixing body 30 and the blades 31 rotate.

When the blades 31 are rotating and so mixing the granulate ice cream base at a temperature under -4 °C, preferably around -10 °C, filled into the work space 12 of the mixing vessel 10, then the sealing body 15b is opened the gas at a pressure of - in this case - 4 bar, which in this case is air, may be introduced into the work space 12 of the mixing vessel 10 through the feed channel 15a of the gas-feed pipe end 15. The high- pressure gas introduced into the work space 12 may be forced, absorbed into the components of the ice cream preparation that is disintegrating into increasingly finer particles with the help of the rotating blades 31 , and due to the temperature being under -4 °C the gas is distributed into the particles of the ice cream preparation and sustained there. When the given amount of introduced gas has been absorbed by the ice cream preparation, the mixing body may be stopped, the cover 20 opened and the volume- increased ice cream preparation under -4 °C may be removed from the work space 12 of the mixing vessel 10 through the transfer opening 13.

It must be noted here that not only air may be used for the production of the ice cream preparation and for its volume-increase, but also nitrous oxide gas or other suitable gas phase medium may be used.

Moving over now to figure 2, it depicts a different embodiment of the unit 1 according to the invention. Here the mixing vessel 10 of the unit 1 is supplemented with a heat exchanger 70 on the external side 1 lb of the wall 11 , which ensures that the work space 12 enclosed by the wall 11 of the mixing vessel 10 and the ice cream preparation located in it is cooled down to a temperature under -4 °C. In this version the mixing body 30 may also be found in the work space 12 of the mixing vessel 10, the torque receiving body 32 of which here also passes through the wall 11 of the mixing vessel 10 with appropriate sealing. The mixing body 30 also has blades 31 the external edges 31a of which here, however, come into contact with the internal side 1 la of the wall 11 of the mixing vessel 10. The reason for this is so that the ice crystals deposited on the internal side 11a of the wall 11 cooled by the heat exchanger 70 may be separated from the internal side 11a of the wall 11. Here also the blades 31 have openings 31b, but apart from this the blades 31 are also curved, which also promotes more intensive and effective mixing.

Naturally, the unit 1 here also has covers 20, of which the one seals the larger diameter transfer opening 13 located at the upper edge of the wall 11 of the mixing vessel 10, while the other seals the smaller diameter transfer opening 14 made at the base of the wall 11 of the mixing vessel 10. A sealing element 41 ensuring a gas-tight seal 40 may be found between the transfer opening 13 and the cover 20 and between the transfer opening 14 and the cover 20, and the covers 20 are forced up against the wall 11 of the mixing vessel by the sealing structures 42 of the gas-tight seal 40.

In the case of this version of the unit 1 the gas-feed pipe end 15 may be found on the cover 20 sealing the transfer opening 13 of the mixing vessel 10, which gas-feed pipe end 15 has a feed channel 15a. Here also the feed channel 15a is sealed by the sealing body 15b built into the gas-feed pipe end 15. In this embodiment the sealing body 15b of the gas-feed pipe end 15 is also coupled with the flow-direction limiting structure 50. Apart from this, however, a pressure regulating device 60 working together with the flow-direction limiting structure 50 is coupled with the gas-feed pipe end 15. The task of the pressure regulating device 60 is to adjust the pressure of the gas passing into the work space 12 through the feed channel 15a of the gas-feed pipe end 15 in accordance with the temperature conditions prevailing in the work space 12 of the mixing vessel 10.

When using the unit 1 illustrated in figure 2 according to the other version of the procedure, after opening the cover 20 belonging to the transfer opening 13 of the mixing vessel 10, the prepared, still liquid phase ice cream base may be poured into the work space 12 through the transfer opening 13 of the mixing vessel 10. Following this, after sealing the cover 20 the blades 31 of the mixing body 30 may be made to rotate with torque connected to the torque receiving body 32, while by starting the heat exchanger 70 the cooling of the wall 11 of the mixing vessel 10 may be started.

As a consequence of the cooling of the heat exchanger 70, the internal side 1 la of the wall 11 of the mixing vessel cools down to under -8 °C, as a result of which the liquid drops of the liquid ice cream base coming into contact with the internal wall 1 la of the wall 11 are frozen. The frozen drops are scraped off the internal side 1 la of the wall 1 of the mixing vessel 10 by the rotating blades 31 and so slowly the liquid ice cream base is transformed into a fine particulate icy mass.

When the average temperature of this icy mass drops to under -4 °C then after opening the sealing body 15b the air set at a pressure of 4 bar by the pressure regulating device 60 passes through the flow-direction limiting structure 50 into the feed channel 15a of the gas-feed pipe end 15, from where it gets into the work space 12 of the mixing vessel 10. The air passing into the work space 12 is mixed into the ice cream preparation formed as an icy mass upon the effect of the rotating blades 31 and is absorbed into it upon the effect of the temperature conditions.

Naturally the introduction of the gas may also be started even before the temperature of -4 °C is reached, but the absorption of the gas at temperatures above -4 °C is not so effective and so the volume-increasing process may take a significantly longer time.

After the desired part of the entire amount of introduced air has been absorbed the volume-increasing of the ice cream preparation ends and the heat exchanger may be switched off as may be the torque on the torque receiving body 32.

Finally after removing cover 20 sealing the transfer opening 14 or the transfer opening 13 the volume-increased ice cream preparation may be removed from the work space 12 of the mixing vessel 10 of the unit 1. Here it must be noted that the unit 1 according to figure 2 may also be fitted into an ice cream making machine, or even the vessel delimiting the work space of an already manufactured device suitable for producing scoop dispensed ice cream preparations but not constructed as a pressure vessel may be converted into the construction according to the invention. In this case the unit 1 forms just a part-unit of the ice cream making device, but this part-unit realises all those characteristics that relate to the invention.

It must also be noted that the volume increasing of the ice cream preparation may be made more effective if before introducing the air or other gas to be absorbed into the work space 12 of the mixing vessel 10 by creating a drop in pressure by removing a part of the air from the work space 12. In this case, naturally, the sealing body 15b and/or the flow-direction limiting structure 50 and/or the pressure regulating device 60 connected to the gas-feed pipe end 15 are of a type complying with this. Also, as illustrated in figure 1, a further gas-extraction pipe end 16 suitable for creating a drop in pressure may also be connected to the mixing vessel. The gas-extracting pipe end 16 may also be suitable for terminating the overpressure in the work space 12 of the mixing vessel 10 after the volume-increasing of the ice cream preparation has been completed.

It is also obvious that the mixing body 30 may not only be located in the wall 11 of the mixing vessel 10 but also in the cover 20 sealing the transfer opening 13 or the transfer opening 14 of the mixing vessel 10. The same may be said of the installation location of the gas-feed pipe end 15 and of the gas-extraction pipe end 16 as well.

It must also be mentioned that the shape of the blades 31 of the mixing body 30 may range within a wide scope, therefore, the shape of the blade 31 presented in the figures supplied with openings 31b is not mandatory. For example, a mixing body 30 assembled from fork-like blades 31 may also be imagined.

The unit according to the invention may be used to good effect for performing quick, reliable, energy-saving and economic volume increasing of ice cream preparations in such a way that the characteristics of the ready, volume-increased ice cream preparation are essentially identical in the various batches.

List of references

unit 0 mixing vessel 11 wall

11a internal side l ib external side

12 work space

13 transfer opening

14 transfer opening

15 gas-feed pipe end 15a feed channel 15b sealing body

16 gas-extraction pipe end 0 cover 0 mixing body 31 blade

31a external edge

31b opening

32 torque receiving body 0 gas-tight seal 41 sealing element

42 sealing structure

50 flow-direction limiting structure 51 flap valve

60 pressure regulating device

70 heat exchanger

"T" gap