A REFRIGERATOR

FIELD OF THE INVENTION

This invention relates to a refrigerator.

BACKGROUND TO THE INVENTION

Refrigerators are known. Most refrigerators require a source of fuel, such as gas or electricity to operate. However, in many situations fuel or electricity is not available, nor is it necessarily affordable.

Where natural resources like water, wind or solar power is being utilized to generate electricity, the added expense of the equipment required to perform such conversion to electricity also becomes a prohibitive factor. Many situations require a refrigerator with a large degree of portability, meaning that an entire solar or wind or water conversion system together with the storage facilities like batteries cannot be practically portable.

In addition, the Inventor has identified a growing concern of global warming largely caused by the world's electricity consumption, for which a normal home refrigerator accounts for about 15% of all household electricity consumption during an average month.

The current invention seeks to propose a possible solution to the above problems.

SUMMARY OF THE INVENTION

According to an aspect of the invention there is provided a refrigerator which includes an enclosure; a condenser positioned outside said enclosure for exchanging heat with the atmosphere, in use;

an expansion valve arranged in fluid communication with the condenser which valve facilitates the flow of refrigerant from a high pressure zone to a low pressure zone, in use, to allow evaporation of said refrigerant; an evaporator positioned inside the enclosure, which evaporator is arranged in fluid communication with the expansion valve for absorbing heat from within the enclosure; and a compressor arrangement arranged in fluid communication with said evaporator and condenser, which compressor is for compressing refrigerant, in use, and is configured for manual actuation by including a suitable mechanism to allow manual energization of said compressor.

It is to be appreciated that, in this specification, the term "manual" refers to actuation not performed by automatic equipment or electrical assistance, but to actuation performed by physical effort by man and/or animal. In addition, reference to the term "manual" must be interpreted to include actuation by natural means, e.g. air, water, or the like.

The mechanism may include a crankshaft configured to actuate a suitable piston of the compressor in a reciprocating manner, or the like. The mechanism may include a suitable gearing system to provide a suitable relationship between input rotation and required rotation of a shaft of the compressor, i.e. revolutions versus torque characteristics.

The mechanism may include a handle for actuating the compressor. The mechanism may include a pedal arrangement for actuating the compressor. The mechanism may be configured for harnessing motive power from an animal, e.g. a mule, a horse, cattle, or the like.

The mechanism may be configured for actuating the compressor under the influence of flowing water, e.g. the mechanism may include a water wheel arrangement, or the like. The mechanism may be configured for actuating the compressor under moving air power, e.g. the mechanism may include a propeller, or the like. The mechanism may include any suitable manual input able to actuate the compressor.

The compressor arrangement may include inertial storage means, such as a flywheel, or the like. The flywheel may be configured so that a mass thereof is easily alterable by said flywheel defining a sealable cavity therein for receiving a liquid, in use. The sealable cavity may include compartments for minimizing fluid movement, in use.

The enclosure may include heat insulation material to maintain cool temperatures in the enclosure, in use. The insulation material may include polystyrene, a gel-like substance, or any other suitable temperature insulating material. The enclosure may define a double-walled arrangement so that a vacuum between the walls provide insulating capability.

The enclosure may include a see-through portion to allow visual identification of the contents of such enclosure without requiring an opening of the enclosure to be opened.

The refrigerator may include a thermostat. Accordingly, the compressor may be configured to charge a suitable pressure storage container, either once the thermostat detects that the interior of the enclosure has reached a particular temperature, or when manually set to do so. The refrigerator may include the pressure storage container, e.g. a fluid cylinder, or the like. It is to be appreciated that the pressure stored when the suitable storage container is charged may be used at a later stage to drive the compressor, or the like.

It is to be appreciated that the refrigerator may include any suitable refrigerant, typically a phase changing substance, or the like.

It is further to be appreciated that the evaporator and condenser, as is conventional practice, are configured to include a large surface area for efficient heat exchange with the interior of the enclosure and the outside atmosphere, respectively.

In addition, the enclosure may include a fan configured to be operated from the mechanical mechanism for circulating cold air inside the enclosure. Similarly, the condenser may include a fan configured to maximize the flow of air across the condenser, in use.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is now described, by way of non-limiting example, with reference to the accompanying drawing wherein Figure 1 shows, in diagrammatic view, a refrigerator, in accordance with the invention.

DETAILED DESCRIPTION OF THE INVENTION

With reference to the accompanying drawings, a refrigerator, in accordance with the invention, is generally indicated by reference numeral 10.

In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the invention. It will be apparent, however, to one skilled in the art that the invention can be practiced without these specific details.

Reference in this specification to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the invention. The appearances of the phrase "in one embodiment" in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Moreover, various features are described which may be exhibited by some embodiments and not by others. Similarly, various requirements are described which may be requirements for some embodiments but not other embodiments.

In general, conventional refrigerators make use of the phase changing properties of certain chemicals known as refrigerants. A characteristic of typically refrigerants is that these refrigerants evaporate at very low temperatures which, in turn, require heat for the change of phase from liquid form to vapour form. In this manner, it is possible to absorb heat at a specific location in order to cool said location.

As such, a refrigerator 10 generally consists of a refrigerant, an evaporator 30, a condenser 14, an expansion valve 16, and a compressor 20. The evaporator 30

is also typically located inside a suitable enclosure 12 in which the temperature is then lowered below ambient, in use.

It is to be appreciated that conventional refrigerators also require some automatic energizing means for actuating the compressor 20. Electric motors are typically used for this task. The Inventor is also aware of natural gas powered refrigerators.

For example, the general refrigeration process will now be explained with reference to Figure 1 commencing with the refrigerant at position 18.2 in the sealed system of the refrigerator 10. In the refrigerator 10, the refrigerant in gaseous form is forced through a system of tubes collectively known as the condenser 14. This forcing is accomplished with the compressor 20 and increases the pressure of the refrigerant and also raises its temperature. On the other side of the condenser 14 at position 18.3, the gas passes through a very thin capillary tube or expansion valve 16, which forms an impediment to the gas flow.

The length of the tubing comprising the condenser 14 together with the lower ambient temperature present at the condenser 14 allows the pressurized gas to cool down and to condensate into liquid form. Due to the impediment to gas flow provided by the expansion valve 16, this liquid refrigerant is at a higher pressure than that present at position 18.4. As the liquid refrigerant continues its pressurized flow through the expansion valve 16, the liquid is allowed to evaporate at the lower pressure portion 18.4 to reach a further tubing system comprising the evaporator 30 which is located inside the enclosure 12 of the refrigerator 10.

This evaporation of the liquid refrigerant at the lower pressure present in the evaporator 30 requires the refrigerant to absorb heat, which it takes from the air inside the refrigerator's enclosure 12. This extraction of heat is what lowers the temperature inside the enclosure 12 to below the ambient temperature outside the enclosure.

Having absorbed heat inside the enclosure 12 allowing the gaseous refrigerant to change phase back into a gaseous form, the refrigerant continues its

journey towards the low-pressure portion at location 18.1 at the input of the compressor 20, from where the entire process repeats itself.

Accordingly, the refrigerator 10, as shown, includes the enclosure 12, and a condenser 14 positioned outside said enclosure 12 for exchanging heat with the atmosphere when in use. Also included is the expansion valve 16 which is arranged in fluid communication with the condenser 14. This valve 16 facilitates the flow of refrigerant from the high pressure zone 18.3 to the lower pressure zone 18.4, in use, to allow evaporation of the refrigerant. In one embodiment of the invention, the valve 16 may be configured to be automatically or manually adjustable in order to adjust the flow of refrigerant through the system. Similarly, the valve may be automatically adjusted according to a thermostat reading, or the like.

Further included is the evaporator 30 which is positioned inside the enclosure 12, with the evaporator 30 arranged in fluid communication with the expansion valve 16 for absorbing heat from within the enclosure 12. In one embodiment, the refrigerant includes carbon dioxide gas which does not present a significant health risk to users should a leakage occur.

The refrigerator proposed by the current invention is characterized in that the compressor arrangement 20 is arranged in fluid communication with the evaporator 30 and condenser 14, so that the compressor 20 is able to compress the refrigerant, in use, and is also further configured for manual actuation by including a suitable mechanism 22 to allow manual energization of said compressor 20.

The mechanism 22 typically includes a suitable gearing system to provide a suitable relationship between input rotation and required rotation of a shaft of the compressor 20, i.e. revolutions versus torque characteristics, and the like. This is generally determined by the speed at which a person is able to turn the handle, for example, and the rotation required by the compressor 20 to allow sufficient compression for refrigeration.

As such, the mechanism 22 may include a handle for actuating the compressor 20, a pedal arrangement for actuating the compressor 20, or the

mechanism 22 may be configured for harnessing motive power from an animal, and/or any suitable manual input.

In addition, the mechanism 22 may also include a water wheel for actuating the compressor 20 under the influence of flowing water, or a propeller for actuating the compressor 20 under wind power, or the like.

In a preferred embodiment of the invention, the compressor arrangement 20 includes an inertial storage means 24, typically in the form of a flywheel. The flywheel 24 is configured so that a mass thereof is easily alterable by said flywheel 24 defining a sealable cavity therein for receiving a liquid, such as water, in use. This sealable cavity generally includes compartments for minimizing fluid movement when the flywheel 24 is rotating. It is to be appreciated that this altering of mass of the flywheel 24 typically reduces the weight of the flywheel 24 for easier carrying when not in use.

The enclosure 12 typically includes heat insulation material to maintain the cool temperatures inside the enclosure 12, in use. This insulation material can include polystyrene, a gel-like substance, and/or any other suitable temperature insulating material. The heat insulation material may include any portion of such material located at any suitable location in or near the enclosure, and may include means applicable as so-called "cold storage" means, such as ice-packs, gel-packs, or the like. In another embodiment of the invention, the enclosure 12 may define a double-walled structure wherein a vacuum or a gas between the walls acts as insulation. It is to be appreciated that in an embodiment where the refrigerator 10 is portable, the insulation material is typically a lightweight material.

In one embodiment, the enclosure 12 also includes a see-through portion to allow visual identification of the contents of such enclosure without requiring opening of the enclosure which prevents heat from entering.

In a further embodiment, the refrigerator 10 may include a thermostat. In addition, the compressor 20 is then configured to charge a suitable container once the thermostat detects that the interior of the enclosure 12 has reached a particular

temperature. It is to be appreciated that the energy stored when the suitable container is charged may be used at a later stage, or the like.

It is further to be appreciated that the evaporator 30 and condenser 14, as is conventional practice, are configured to include a large surface area for efficient heat exchange with the interior of the enclosure 12 and the outside atmosphere via the condenser 14, respectively.

In addition, as shown, the enclosure 12 include a fan 28 configured to be operated from the mechanism 22 to circulate cold air inside the enclosure 12. Similarly, the condenser 14 includes a fan 26 configured to maximize the flow of air across the condenser 12, in use, and is also powered from the mechanism 22.

It is to be appreciated that the refrigerator 10 may also be applied as a freezer for freezing goods, or the like. The refrigerator may be shaped and dimensioned according to a particular application or requirement, such as a small flask or a walk-in fridge, or the like.

Although only certain embodiments of the invention have been described herein, it will be understood by any person skilled in the art that other modifications, variations, and possibilities of the invention are possible. Such modifications, variations and possibilities are therefore to be considered as falling within the spirit and scope of the invention and hence forming part of the invention as herein described and/or exemplified.

It shall further be understood that the examples are provided for illustrating the invention further and to assist a person skilled in the art with understanding the invention and is not meant to be construed as unduly limiting the reasonable scope of the invention.

The Inventor regards it as an advantage that the invention provides for a refrigerator which is usable independently of the availability of power sources such as electricity or gas, which finds particular application in the fields of medicine, outdoor activities, military applications, and the like.