The invention relates to a dispensing unit for dispensing ice, snow or snow like particles to a customer on demand. In particular, the invention relates to a machine for making instant packing ice or powdered snow for use as an ice or crushed ice substitute. Typically such products are used for cooling foods and beverages in ice boxes, coolers and the like. The present specification forms part of a continuation-in-part application based on our earlier application Ser. No. 10/475,228.
Over the years, a number of methods of making snow have been proposed, and two examples will now be discussed.
The “Polar Process” is a cryogenic form of snow making, where liquid nitrogen (N2) is mixed with water atomised by an air compressor in a snow pipe to make snow. This has proven a popular form of snow production for events and promotions. While the capital cost is not great, the operational costs for making the snow are very high, as up to 500 kg of liquid nitrogen is required to be mixed with water to form one cubic metre of snow.
Another known method is the “Crushed Ice Process”. This process of snow production is expensive and very labour intensive and the snow product is more in the form of shaved ice, and not a true snow crystal. The process relies on the production of, say, 150 kg, blocks of ice which are transported to a site, where they are put through an ice grinding machine to be shaved into shaved ice particles for use as snow. The process is expensive as the blocks are expensive to buy, and require specialised transport and labour to transport and handle the blocks. The machinery to make the ice blocks is large and cumbersome, and there are very few ice-making works capable of producing the blocks. The use of this form of snow production for events has been limited.
The supply of ice cubes in plastic bags is a multi billion industry throughout the world. The ice can be supplied in 2 ways. The first way is through an ice making factory where the ice is first produced by ice making machines. The ice produced is transported by conveyor to be bagged, stockpiled on a pallet, transported to a cold room where it is stored for later use, transported to a truck that delivers it to a service outlet where it is unloaded into a smaller storage box requiring refrigeration, where the customer can purchase and use the ice for their intended use. The product when used by the customer has gone through a number of refrigeration processes and it is not uncommon for the ice cubes to have frozen together making them impossible to separate without first applying force. Further, because of the large particle size being between ½ to 1 cubic inch (1.3 to 2.5 cm), it is difficult to distribute the ice evenly to the food to be cooled.
The second known mode of operation is where the same type of ice particles are formed but are done so at the point of sale of the product. In this application a small capacity ice making machine is installed and the ice is made and bagged by a machine. The bags are then stored at the premises for sale. The system requires mechanical refrigeration both to make and store and the machines are normally built to meet the peak demand period. As ice is a product with seasonal use, there is a lot of redundancy and down time with the system. In both cases the capital expenditure is high to set up the operating plants and the returns need to be generated in the peak seasons.
In accordance with a first aspect of the present invention, there is provided a dispensing unit for dispensing ice, snow or snow-like particles to a customer, the unit including:
Preferably the invention described in this document relates to a self dispensing machine that can deliver optionally a 40 pound, 20 pound or 7 pound bag of packing ice (snow) every 30 seconds by feeding a container such as a bag or tub into the machine. The container may be purchased by the customer from the shop assistant and then placed by the customer at the feed section of the machine. The container may include a scanner code. Once the machine reads the scanner code, the machine knows that the container is in place and it starts the process of filling the container with packing ice. In the present form of the invention, the code reader comprises the actuation device to commence operation of the apparatus. In an alternative form of the invention, a button or a coin or note insert mechanism may start the process. Alternatively, tokens may be inserted in place of currency. The coin/token/note receptor may comprise the actuation device to commence operation of the apparatus.
Once the process is started, preferably water and liquid refrigerant are mixed together in a mixing process to produce a granulated or particulate product referred to as packing ice. The packing ice produced is expelled from the machine to fill the container below. The process is quick and energy efficient as power is only used at the time of making the product and there is no requirement for storage, transport or expensive refrigeration or bagging equipment. As well, the cost of producing the product may be a similar gross cost as the current method of producing bagged ice but the consumer is provided with a free flowing product that is easy to spread in their cooler box. The packing ice can also be provided at a desired selected temperature from 0 degrees Celsius to −20 degrees Celsius or lower for use.
The packing ice making machine may be operated by adding pure water to liquid carbon dioxide, nitrogen or similar type of cryogenic refrigerant whereby a mixture of both are mixed in the machine as described below to convert the mixture into a powder ice product for immediate use by the consumer. The machine can also be operated by adding other liquids such as soft drinks, syrup and also other ingredients such as pure ice.
The cryogenic material or refrigerant can be recycled for reuse. The amount of cryogenic material such as carbon dioxide or nitrogen can be as little as 2 to 10% of the total mixture and up to 99% of this material may be recovered for further use. The mixing of the materials may be done in a specially designed insulated vessel that can create the powder snow product in amounts of up to 40 pounds or more in less than 10 seconds.
The packing ice or snow produced by this cryogenic process may also be created to have a longer life cycle than any other snow produced by varying the amount of cryogenic material included in the process. This also makes the storage of the product in cold rooms more favourable as the snow does not stick together due to the elimination of water from the final product.
Preferably, an additive, such as salt, sugar or other soluble material, is included in the mixture, preferably in the range of 0.25% to 1.0% (w/w).
Preferably, the cryogenic material constitutes 2% to 10% (w/w), more preferably 5% to 7% of the mixture.
Preferably, the cryogenic material is placed in the mixing vessel, before the introduction of the water and/or ice, to assist in cooling the walls of the vessel.
Preferably, the mixture is agitated or mixed by at least two sets of rotating blades or knives, which are preferably mounted on the shaft, rotatably journalled in the vessel. Preferably, the first set of blades or knives urge the mixture in a direction opposed by the second set of blades or knives.
The resultant snow may be tipped from the vessel into a suitable receptacle; may be discharged from the vessel by gravity via a valve; be drawn from the vessel by vacuum or suction means; or be discharged through an outlet in a side wall of the vessel by centrifugal force; or by other suitable discharge means.
In order that the invention may be more fully understood, some embodiments will now be described by way of example with reference to the drawings in which:
FIGS. 6 to 8 are schematic views of alternative apparatus for discharging the snow from the mixing vessels;
Referring to
A shaft 15 is rotatably journalled in the bottom wall 14, substantially c-axial with the vertical axis of the vessel 10. The shaft 15 is driven via an electric motor 16 via a drive system 17 (eg., mechanical transmission/pulleys and belt/sprockets and chain).
Respective first and second blades 18,19 are mounted on the shaft 15 at spaced locations and extend substantially radially to the shaft 15. As per the second embodiment shown in
A snow discharge outlet 20 is provided in the side wall 13, or floor 14, of the body 11 and is selectively closable by a valve controlled by an air cylinder 21.
The top wall or lid 12 has a cryogenic material inlet 22, a water inlet 23 and an additive inlet 24, where each may have a respective inlet valve (not shown).
Dry ice (CO2) pellets or snow are deposited into the mixing vessel 10, via the inlet 22, from a storage source or snow horn 25. Water is deposited into the mixing vessel 23, together with an additive (eg., sugar/salt/at a concentration of 0.25-1.0% (w/w)). The electric motor 16 is operated to drive the shaft 15 and the mixture in the mixing vessel 10 is agitated/mixed by the blades 18,19 to cause the water to be converted into snow crystals, eg., within 10-15 seconds.
Preferably, the shaft 15 is rotated between 300 rpm and 5000 rpm, with 2000 rpm to 3000 rpm being a typical rotational speed. It is believed that the release of the CO2 gas from the dry ice, together with the agitation/mixing of the mixture by the blades, operates to “aerate” or “foam” the mixture so that the water is converted into fine snow crystals of a nature identical, or similar, to natural snow. The snow produced by the present method has an appearance, texture and/or characteristic equal, or substantially identical, to natural snow.
The snow crystals are discharged into a suitable container 26, eg., a wheeled bin by operation of the air cylinder 21 to open the snow discharge outlet 20.
The operation is then repeated for the next batch.
The CO2 gas released from the dry ice can be recovered for recycling into liquid or solid CO2, to minimise the operational costs.
The CO2 gas is drawn from the vessel 10 via a gas outlet 27 by a non-lubricating compressor 28, which compresses the CO2 to, eg., 12 Bar. The compressed CO2 gas is passed through at least one drier 29 and condenser 30 to remove any water moisture. The dried gas is then passed through an evaporator 31 of a refrigeration unit 32, the evaporator being at a temperature of −5 C. to −70 C., preferably approximately −20 C.
The CO2 gas will liquefy and collect at the bottom of the liquefier unit 33 and may be stored at a pressure of 1-3 Mpa, at −20 C. or lower, before return to the vessel 10 via CO2 line 34 and liquid CO2 inlet 35. The inlet 35 incorporates expansion valves and/or expansion chambers 35a to cause the liquid CO2 to be released into the vessel 10 in the form of CO2 snow or like solid particles, for mixing with the aqueous mixture in the vessel 10.
The CO2 from the liquefier unit 33 may be stored in a tank (not shown) or be directed to the CO2 source 25 when the mixer vessel 10 is not in operation.
In low temperature applications such as at a ski resort, the low ambient temperatures may be sufficient to condense the gaseous CO2 avoiding the need for the refrigeration unit 32.
For safety, the mixing vessel 10 can be provided with a gas safety valve (not shown).
Referring now to
The snow can be discharged via the snow discharge outlet 120 onto a belt conveyor 140 into containers 126 on a vehicle 150 for transport to a remote site, eg., a sports stadium, sporting event or the like.
Ice, in block and/or lump form, is discharged from an ice making machine 160 through an ice inlet 136 provided with an inlet valve 137 and is mixed with CO2 gas or liquid injected via CO2 gas inlet 122 and water injected via water inlet 123, the CO2 gas and water being supplied from respective sources 170,171.
The water/ice/CO2 mixture is agitated/mixed by the blades 118,119 and the water/ice are converted to snow, for periodic, or batch, discharge via the snow discharge outlet 120.
The CO2 gas liberated by the mixing may be drawn off via a CO2 gas outlet 127 and may be refrigerated to a liquid state by a refrigeration unit 132 and returned to the CO2 source 170 for re-use.
In the modified embodiment of
The method of making the snow is as hereinbefore described and the resultant snow may be discharged via the snow discharge outlet 220, onto a conveyor 240 and into a storage or transport container 226 or vehicle 250.
The snow discharge outlet 20,120,220 may be provided in the side wall 13,113,213, of the mixing vessel 10,110,210, for discharge of the centrifugal force due to the blades 18, 19,118,119 rotating at, eg., 500-3000 rpm; or be provided in the floor 14,114 to enable gravity discharge from the mixing vessel 10,110,210.
A blower 324 forces pressurised air through an air pipe 325 and snow released via a rotary valve 326 is entrained in air flow 327 through a blower pipe 328 for pneumatic transfer to a remote location.
In the embodiment of
In the alternative embodiment of
In a further alternative embodiment (not shown), the top wall (or lid) 12,113 may be hingedly connected to, or removable from, the mixing vessel 10,110 and the latter may be tipped to discharge the snow from the vessel. This arrangement would preferably only be used for small volume, batch-type machines.
For ski slopes, the snow-making machine could be mounted on a vehicle, eg., a prime mover or trailer; to discharge the snow directly to the skiing slope.
The snow produced can be of a quality for use in the food and/or beverage industries, eg., to cool food, such as seafood (such as seafood for display or transportation); mixed in drinks as an alternative to ice; or the like.
As up to 99% of the cryogenic material, eg., the dry ice, can be recovered (and re-used), the cost of production is minimised.
The machines can be scaled to suit the particular snow requirements of a particular installation or site; can be mobile; or can be installed in an ice works.
Advantages of the above described snow making machines include:
Various changes and modifications may be made to the embodiments described and illustrated without departing from the present invention. For example, as illustrated in
FIGS. 9 to 11 are illustrative of the features of the invention claimed in the present application. Referring to the attached drawing the dispensing unit 601 comprises a mixing vessel of between 2-100 litres capacity, preferably in the form of an insulated stainless steel tank that holds water. The mixing vessel can also be made from polypropylene, plastic, mild steel or other non corrosive metals.
The vessel can be made of any size. Inside the vessel is a mixing implement 602 with sheer blades 603 that extend to the radius of the tank. Each vessel will have between 1 to 10 blades that can be spaced at 5 to 20 mm apart and are limited to the bottom half of the vessel. This will allow sufficient space for the aerated packing snow that is to be formed in the top half 604 of the vessel. The mixing vessel can also use other forms of mixing blades and utensils that are commonly used in sheering or milling vessels. The blades are attached to a centre shaft 605 that is connected to a rotating motor 606.
The ingredients are added by way of the clean filtered water pipe line and a liquid refrigerant feed line 608. Optionally, ice may be added from ice hopper 607.
The mixing implement 602 is rotated at 450 to 3000 rpm or more by a suitable hydraulic, air or electric motor 610. At the same time as the motor operates, a blower fan attached to the exhaust 611 removes any expandable refrigerant gas from the cryogenic material that is used in the process.
The machine can be placed on a tipping stand 612A. At the end of the cycle the mixing vessel or the machine can be tilted by an air ram or similar device to drop the packing ice into the container 612B. Alternatively the side gate 612 of the tank is opened by a cylinder 613 controlled by a solenoid valve and the snow is thrown from the tank by centrifugal force when the door is opened at the end of the cycle. The packing ice formed is collected in a container or bag 612B which can be placed by the consumer or operator into position or automatically placed into position by the machine. In another form of the invention, the machine may have a removable base that allows the packing ice formed to drop out.
In a preferred form of the invention a recovery system can be built into the process to recycle the cryogenic material and further reduce the cost of snow production.
Referring to
The CO2 liquid that is collected can be stored in a pressure vessel 620 at a pressure of 1 to 3 Mpa and can be maintained at a temperature of −20 degrees Celsius or lower. The liquid CO2 can be returned to the machine 601 by line 621 for reuse in the snow making system. A solenoid valve 622 is provided to control the flow. Expanding chambers (not shown) placed at the entry point of the liquid allow for the liquid to be released into the snow making machine as carbon dioxide snow. A suitable quantity is added and mixed with the aqueous solution to be made into packing ice. The CO2 snow is returned to its gaseous state and the cycle is again repeated. This process of recycling the CO2 cuts down on green house gas emissions and substantially reduces the cost of the snow produced.
A large liquid CO2 reservoir could be created to hold the liquid when not needed for use. The process described above may be appropriate for use with other cryogenic materials.
Referring to
The foregoing describes only some embodiments of the present invention and modifications can be made thereto without departing from the spirit of the invention set out in the following claims.
It will also be understood that the term “comprising” (or its grammatical variants) as used in this specification is equivalent to the term “includes” and should not be taken as excluding the presence of other elements or features.
The foregoing prior art discussion does not form part of the common general knowledge.
It will be understood that the invention disclosed and defined herein extends to all alternative combinations of two or more of the individual features mentioned or evident from the text or drawings. All of these different combinations constitute various alternative aspects of the invention.
Number | Date | Country | |
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Parent | 10475228 | Mar 2004 | US |
Child | 10909491 | Aug 2004 | US |