ES2551410T3 - Improvements in or relating to refrigeration - Google Patents

Abstract

A refrigeration apparatus comprising a cavity for receiving a product (20) to be refrigerated; a rotating means for rotating the product received in the cavity and coolant supply means to provide a coolant to the cavity; wherein the means of rotation is adapted to rotate the product (20) around two parallel shafts (21, 22); and in which one of the axes (21) is an axis of the product.

Description

5

10

fifteen

twenty

25

30

35

40

Four. Five

fifty

55

E11710555

10-27-2015

DESCRIPTION

Improvements in or relating to refrigeration

The present invention relates to improvements in or relating to refrigeration.

In the catering, retail and entertainment sectors, various forms of sales devices are used to keep products cool. For cold drinks these devices form two typical groups of commercial beverage refrigerators and machines for selling cold drinks. Both types of devices are essentially large refrigerators with front glass that have hinged or sliding doors in the case of the first group (for manual dispensing) or a dispensing mechanism in the case of the second. They previously refrigerate and store ready-to-buy drinks. In many cases, drinks are kept at low temperatures for long periods before they are finally purchased. As a result, considerable energy is used potentially unnecessarily. Increasing the problem, both types of devices work inefficiently. During use, the first group beverage refrigerators suffer substantial losses of cold air each time the large door is opened. Sales machines must provide an easy step to the sales tray when the item is picked up by the user, resulting in poor sealing. Refrigeration systems generally have the requirement to be exercised through background execution cycles to maintain efficiency, but this uses additional energy that does not directly contribute to the cooling of the content.

The storage of beverages in refrigerated cabins with the front open for easy access and visibility of the product is also known to many beverage retailers. These cabins obviously suffer from an even greater waste of energy.

The net result is high levels of wasted electrical energy used keeping drinks in a long-term cold state ready for purchase, regardless of when this may occur.

Energy waste is not limited to corporate locations that maintain vending machines. Many small stores, gas stations and coffee shops maintain beverage cooling booths. For these operators, electricity costs represent a high proportion of their operating costs. Waste of energy is not the only problem. Since refrigeration systems generate heat, frequently wasted heat energy as a byproduct of refrigeration systems causes unwanted heating of the area around the machines. This creates an inconsistency in which users should drink their drinks satisfactorily cooled in unsatisfactorily hot areas.

The speed of refrigeration is also a problem, particularly in establishments that have a high volume of beverages, such as special events - concerts, sporting events and the like. Frequently at the beginning of the event the drinks are properly refrigerated having been in the refrigerators for several hours. However, once the event is in progress, the volume of beverages sold exceeds the capacity of the refrigerators to cool additional beverages. The drinks should then be sold only partially cooled or not cooled at all.

The present invention seeks to tackle these problems by providing an apparatus that allows the cooling of beverages on demand. The apparatus can be a stand-alone device or it can be incorporated into a vending machine.

US 4,172,365 (McClintock) describes a reliable refrigerator for transporting and cooling drinks in boats.

The previous application of the present inventors, WO2011 / 012902, describes a refrigeration apparatus comprising a cavity for receiving a product to be refrigerated. The apparatus comprises a means of rotation for rotating a product received in the cavity and a means of supplying coolant fluid to provide a coolant fluid to the cavity. The reader is referred to that cited publication for additional background. The rotation means is adapted to provide a pulsed or discontinuous rotation for a predetermined period.

The present inventors have developed an apparatus comprising a cavity for receiving a canister or other container for a beverage to be refrigerated. The cavity includes a motor-driven rotary table to allow the beverage to be rotated at speed and also includes means for keeping the boat in position on the rotating table while rotation is allowed. The apparatus also includes means for supplying a cooling liquid. The cavity itself can be rotated or the container can be rotated inside the cavity.

A sealed boat cooling platform was manufactured for the use of a salt water solution that is cooled to approximately -16 ° C, in a cooling tank with a rotary stirrer to reduce salt solidification. A diaphragm pump was used to fill the cooling vessel, at a rate of up to 5 liters / minute. The cooling vessel was designed to accept a standard boat, which can be rotated up to 12 Hz / 720 RPM. Pump flow and boat rotation speed are controllable. Speeds were recorded

5

10

fifteen

twenty

25

30

35

40

Four. Five

fifty

E11710555

10-27-2015

Real-time cooling of the drink.

The present inventors have determined that, during the rotation of a boat, a forced vortex is developed, the depth of which inside the boat depends on the speed of rotation. A forced convection takes place and creates artificially induced convection currents inside the boat. Then when the rotation stops, a free or collapsing vortex is formed and a natural convection takes place, promoting the mixing of the contents of the boat but without the incorporation of air bubbles that could lead to nucleating and excessive effervescence.

However, in a static boat without this collapsing vortex, as the coldest drink is denser, it is submerged towards the base of the boat. The mixing of the contents of the boat is very poor, leading to poor thermal uniformity, and also leading, in many cases, to the formation of ice or "slush". In the previous work of the present inventors, it was determined that intermittent or pulsed rotation overcame this problem. However, this introduces delays in refrigeration since the beverage container is slowed down and brought back to speed.

The present invention seeks to provide additionally improved cooling rates.

Accordingly, the present invention provides a refrigeration apparatus comprising a cavity for receiving a product 20 to be refrigerated; a rotating means for rotating a product received in the cavity and coolant supply means to provide a coolant to the cavity; wherein the rotation means are adapted to rotate the product 20 around two unmatched parallel axes 21, 22; and in which one of the axes 21 is an axis of the product.

Preferably, the rotation means is adapted to rotate the product at a rotation speed of 90 revolutions per minute or more, more preferably at least about 180 revolutions per minute, even more preferably at least about 360 revolutions per minute.

Preferably, the refrigerant is a refrigerant fluid and the means of supply of the refrigerant fluid is adapted to provide a flow of refrigerant fluid to the cavity.

Preferably, the cooling fluid is supplied to the cavity at a temperature of -10 ° C or less, more preferably -14 ° C or less, even more preferably -16 ° C or less.

In certain embodiments, the apparatus comprises a plurality of cavities as defined above.

In typical embodiments, the apparatus is incorporated into a sales apparatus and the sales apparatus further comprises insertion and extraction means for the insertion of the product to be refrigerated in the cavity and the extraction of the refrigerated product therefrom.

Preferably, the sales apparatus further comprises storage means for the storage of a product or range of products and selection means for the selection of a product from the storage medium for insertion into the cavity.

The foregoing and other aspects of the present invention will now be described in additional detail, by way of example only, with reference to the accompanying drawings, in which Figure 1 is a perspective view of an apparatus that is not in accordance with the present invention although it is useful for the explanation of some details of the invention; Figure 2 is a graph showing the cooling rates obtained in various tests on the apparatus of Figure 1; and Figure 3 is a schematic plan view of an apparatus according to the present invention.

In its crudest form, the cooling liquid is simply poured into the cavity and then extracted at the end of the cooling process. In preferred embodiments, a flow of coolant is provided through the apparatus.

Figure 1 shows the equipment 10 comprising a cavity 11 for receiving the beverage container mounted on a table 12. The cavity 11 is rotatable by means of an electric motor 13 mounted below the table 12. The table 12 moves alternatively, when the slide is mounted on a pair of parallel tracks 14 and is caused to oscillate by means of a cam arrangement comprising an eccentrically mounted link bar 15 driven by an additional motor 16. The link bar 15 is adjustable to provide a variable travel range of 5 to 25 mm. Alternative arrangements are apparent to those skilled in the art, including gear arrangements to allow the use of a single motor. Consequently, the apparatus can apply a movement to a beverage container placed in the cavity 11 around two degrees of freedom - a rotation movement around the axis of rotation of the cavity 11 and a linear movement around the direction of the alternative movement from table 12—.

The cooling rates achieved for a 330 ml aluminum pot at room temperature are shown in Figure 2. The rotation speed in the three cases was 350 revolutions per minute. The alternative movement was at a speed of 120 oscillations per minute with a single travel length of 18.5 mm

5

10

fifteen

twenty

25

30

35

40

Four. Five

fifty

E11710555

10-27-2015

(equivalent to a movement of 74 mm / s). The coolant temperature was -14.5 ° C flowing through cavity 11 at a speed of 4.25 l / min. The effective volume of the cavity was 650 ml, which is equivalent to a jacket of refrigerant fluid of approximately 20 mm around a standard diameter canister.

As a control, the cooling rate that can be achieved by the apparatus of WO2011 / 012902 (rotation interrupted only without linear movement) is shown as line (i), showing cooling from an exemplary ambient temperature of 22 ° C to 4 ° C in a liter in 70 seconds. In comparison, the equipment in Figure 1 achieved refrigeration at 4 ° C in 54 seconds (line iii), and 58 seconds (line ii), an improvement of 18-23%.

It has been suggested that the apparatus leads (at least in an idealized arrangement) to the development of a Rankine vortex within the beverage container. Visual observation in a transparent cavity 11 and a transparent beverage container confirms that this is the case.

Other techniques are possible for the generation of Rankine vortices or a vortex similar to Rankine, including epicyclic rotation, single plane agitation, and multi-plane agitation; by introducing asymmetries in the container, for example by means of a localized groove, off-axis rotation or rotation of the container perpendicular to its axis; or the introduction of a shock wave into the vessel during rotation; an introduction of a centripetal force, for example.

In essence, a vortex such as a vortex similar to Rankine results in a tangential velocity that is not equal to the angular velocity multiplied by the radius along the entire radius. As a result the drink does not behave as a solid dough, there is a presence of rupture and therefore the mixing takes place.

In typical embodiments, the apparatus is incorporated in a sales apparatus and further comprises insertion and extraction means for the insertion of the product to be refrigerated in the cavity and the extraction of the refrigerated product therefrom.

Preferably, the sales apparatus further comprises storage means for storage of a product or range of products and selection means for the selection of a product from the storage medium for insertion into the cavity.

The sales apparatus will also typically include a payment collection apparatus such as a coin operated mechanism or a card reading apparatus for deducting a charge from a card.

The beverage container of Figure 3 shows an arrangement in which the container is rotated in an epicyclic manner. That is, the apparatus includes a main rotation means for the rotation of the container, such as a boat 20, around its own axis 21 and a secondary rotation means for rotating the axis of the boat around a non-coincident parallel secondary axis 22 . Said rotational arrangement provides greater agitation of the beverage itself, thereby reducing the temperature gradients with the container.

Convection heat transfer is largely controlled by the fluid flow rate within the boundary layers. Increasing the velocity gradient within the boundary layer will increase heat transfer by convection. Although the Reynolds number is a key parameter that controls whether the boundary layer is laminar or turbulent, it may change due to surface textures or roughness and the local pressure gradient. The more complex movement of the container and the refrigerant provided by this arrangement gives more degrees of freedom to control the thickness and velocity of the gradient within the boundary layer. This allows the apparatus to maximize heat transfer by convection while eliminating the formation of slush or ice that has hindered past attempts to achieve rapid cooling.

The present invention also seeks to provide a sales machine incorporating the apparatus described above. In a conventional vending machine, the entire storage cavity should be insulated, but the insulation for a cavity that stores perhaps 400 boats can typically only be achieved using insulating foam or padding or other materials that trap the air to prevent heat transmission. These materials are relatively inefficient thermal insulators.

In addition to providing a vending machine that cools drinks exclusively on demand, the present invention provides a vending machine in which most of the cans or other beverage containers can store me at room temperature and only a small number, perhaps 16 or so, they can be stored at a reduced temperature or for drinking.

As a result, the cavity in which the containers are stored at reduced temperature can be isolated with more effective means, such as vacuum insulation panels. The cooling apparatus is provided between the ambient storage cavity and the cooled storage cavity.

The use of two storage areas significantly reduces the overall energy consumption and will also reduce the nominal power required for the rapid cooling apparatus.

E11710555

10-27-2015

A low level of additional cooling can be provided to the cooled storage cavity to maintain the correct temperature, but the energy consumption to maintain the temperature in a small vacuum insulated capacity cavity is substantially lower than in conventional machines.

Claims (6)

1. A refrigeration apparatus comprising a cavity for receiving a product (20) to be refrigerated; a rotating means for rotating the product received in the cavity and coolant supply means to provide a coolant to the cavity; in which the rotation means is adapted to rotate the product (20) 5 around two axes (21, 22) not coincident parallel; and in which one of the axes (21) is an axis of the product. 2. A refrigeration apparatus according to claim 1, wherein the rotation means is adapted to rotate the product (20) at a rotational speed of 90 revolutions per minute or more, more preferably at least about 180 revolutions per minute, even more preferably at least about 360 revolutions per minute. A refrigeration apparatus according to any preceding claim, wherein the refrigerant is a cooling fluid and the means of supplying the cooling fluid is adapted to provide a flow of cooling fluid to the cavity. 4. A refrigeration apparatus according to any preceding claim, wherein the cooling fluid is supplied to the cavity at a temperature of -10 ° C or less, more preferably -14 ° C or less, even more preferably 15 -16 ° C or less.

5.

 A refrigeration apparatus according to any preceding claim, wherein the rotation means is adapted to provide a pulse or discontinuous rotation for a predetermined period.

6.

An automatic sales apparatus comprising a refrigeration apparatus according to any claim

above, and also comprising means for insertion and extraction for the insertion of the product (20) to be refrigerated in the cavity and the extraction of the refrigerated product therefrom. 7. An automatic sales apparatus according to claim 6, further comprising storage means for storing a product (20) or range of products and selection means for selecting a product (20) from the storage medium for its insertion inside the cavity. 6