GB2059038A - Refrigerated probes - Google Patents

Abstract

The invention relates to refrigeration apparatus (10) having a probe (19) projecting outwardly therefrom, the refrigeration apparatus being operable to cool the probe and the probe (19) being insertable into a container (38) to cool any contents such as, for example milk, soft drinks or wine, of the container. As shown, the probe comprises an evaporator (18), a thermostat (28) and a paddle stirrer (30). <IMAGE>

Description

SPECIFICATION Refrigeration apparatus The invention relates to refrigeration apparatus.

The invention provides refrigeration apparatus having a probe projecting outwardly therefrom, the refrigeration apparatus being operable to cool the probe and the probe being insertable into a container to cool any contents of the container to cool any contents of the container.

It will be appreciated that since the refrigeration apparatus according to the invention has a probe which projects outwardly therefrom, unlike known refrigeration apparatus, the probe is easily accessible to be cleaned and can also be used to cool the contents of a variety of containers by being inserted therein.

The refrigeration apparatus may have a switch arranged to switch the refrigeration apparatus on when the probe is inserted into a container. The switch may be arranged to engage with and be operated by the container, the switch being switched off again when the probe is removed from the container.

The refrigeration apparatus may have an agitation means arranged to agitate the contents of a container once the probe has been inserted into the container. The agitation means may comprise a paddle stirrer or a vibration means.

The refrigeration apparatus may be provided with mounting means for securing the apparatus to a wall or the like surface.

The refrigeration apparatus may be provided with fastening means arranged to releaseably secure to the refrigeration apparatus a container in which the probe has been inserted.

Sealing means may be provided to seal around an opening of the container in which the probe has been inserted, to restrict the passage of air moisture or the like into, or from the container.

The probe may comprise a tube and the refrigeration apparatus may be arranged to supply refrigerant to the tube.

Preferably the tube is looped and/or coiled so that the refrigerant can be recirculated back to the refrigeration apparatus. The tube may be formed of stainless steel to inhibit the corrosion thereof, and to facilitate cleaning of the tube.

Preferably the refrigeration apparatus is thermostatically controlled.

It is preferred that the refrigeration apparatus further comprises a container arranged to receive the probe, the container being releaseably securable to the refrigeration apparatus. The container is preferably formed of stainless steel or the like corrosion resistant material which can be easily sterilised or otherwise cleaned. The container may be insulated so as to reduce the transfer of heat from the environment to the container or its contents.

The container may have a dispenser such as, for example a tap arranged to dispense the contents of the container therefrom. The container may also be sealable when removed from the refrigeration apparatus so that the contents thereof can be isolated within the container. The container may have a relealable aperture through which the probe can be inserted, through which the probe can be inserted, and a sealing means may be provided on the container to seal around the probe as the probe is inserted into, or withdrawn from the container and/or when the container is releaseably secured to the refrigeration apparatus.

Two embodiments of a refrigeration apparatus according to the invention will now be described, by way of example only, with reference to the accompanying drawings of which; Figure 1 is a diagrammatic side elevation of a refrigeration apparatus incorporating a container, and Figure 2 is a part-sectional side elevation of an alternative form of probe and evaporator for the apparatus shown in Fig. 1.

Referring now to Fig. 1 of the drawings, a refrigeration apparatus is indicated generally at 10 and comprises a compressor 12, a condenser 14, a fan 1 6 and an evaporator 1 8 in the form of a probe 1 9 extending downwardly from the apparatus 1 0. The refrigeration apparatus 10 is supported on a plinth 20 having wall mounting brackets 22 located on, and upstanding one from each side thereof.

The brackets 22 are arranged to be secured to a wall or other support surface (not shown) for example, by screws (not shown), so that the refrigeration apparatus can be mounted on the wall or other surface.

The evaporator 1 8 comprises a U-shaped tube 24 formed of stainless steel, and the "arms" of the U-shaped tube each extend through a respective aperture (not shown) in the plinth, the tube 24 thus projects downward away from the plinth 20 with the base of the U being remote from the plinth. The tube 24 is coiled at 25 which increases the available surface area of the tube over which heat can be transferred to the tube.

A series of copper conduits 26 interconnect the compressor 1 2 and the evaporator 18, the evaporator 1 8 and the condenser 14, and the condenser 14 and the compressor 12. A closed circuit is thus formed in which a working fluid (not shown) can be circulated.

The refrigeration apparatus 10 is arranged to be connected to a mains electrical supply (not shown) so that when the electrical supply is connected to the apparatus 10 a refrigeration operation is commenced so that the working fluid (not shown) is circulated through the apparatus around the closed circuit thereof.

During the refrigeration operation the working fluid (not shown) is pumped under pressure from the compressor 1 2 through a conduit 26 to the condenser 14 where heat from the working fluid (not shown) is dissipated by the fan 1 6 which circulates air (not shown) over the condenser 14 to promote heat transfer from the working fluid through the condenser to the air passing thereover. The result of the heat lost by the working fluid (not shown) in the condenser 14 and the pressurisation of the working fluid by the compressor 12, is that the working fluid condenses to a liquid within the condenser 1 4.

The now liquid working fluid (not shown) passes via a drier 27 to a capillary tube 29 where it is expanded to a lower pressure and passes on via a second conduit 26 to the evaporator 1 8. As the pressure of the working fluid (not shown) is lowered it begins to vaporise within the evaporator 1 8. As it vaporises, the working fluid extracts the latent heat required for its vaporisation from the tube 24, and the ambient fluid (not shown) immediately surrounding the outside of the tube 24. The vaporised working fluid (not shown) is then returned in a further conduit 26 to the compressor 1 2 under the suction provided by the compressor.The vaporised working fluid returned to the compressor 1 2 is thereafter pressurised by the compressor 1 2 for re-circulation to the condenser 14 ready for a second cycle of the refrigeration operation to commence.

The net result of the refrigeration operation is that heat is extracted from the tube 24 and the ambient fluid (not shown) by the working fluid (not shown), the heat being later given up by the working fluid in the condenser 14.

As heat is progressively transferred to the working fluid (not shown) from the tube 24 and the ambient fluid (not shown) on each cycle of the refrigeration operation, the tube 24 and the ambient fluid become correspondingly cooler. It will therefore be appreciated that when the tube 24 is placed in any fluid (i.e. the ambient fluid) the latter fluid is cooled on energisation of the refrigeration apparatus 10. There is, however, a limit to the degree of cooling which can be achieved by the-refriger- ation apparatus 10, and eventually on pro longed energisation of the apparatus 10 a steady state minimum temperature of the tube 24 and ambient fluid is reached beyond which no further cooling action takes place.

The tube 24 and the ambient fluid can, however, be maintained at any temperature between the ambient temperature and the minimum temperature by controlling the ener gisation of the apparatus 10 and hence controlling the duration of the refrigeration operation. For this purpose a thermostat 28 is connected to the refrigeration apparatus 10 and extends through an aperture (not shown) in the plinth 20 downwardly adjacent to the tube 24. The thermostat can be preset to regulate the energisation of the apparatus 10 to maintain the tube 24 and the ambient fluid (not shown) at any predetermined desired temperature within its working range of between ambient temperature and the minimum temperature as mentioned above.Because the thermostat 28 is located adjacent to the tube 24, it is capable of responding accurately to any change in the temperature of the tube 24 and the ambient fluid to return them to the predetermined temperature in a relatively short space of time.

A mechanical paddle stirrer 30 is located through a hole (not shown) in the plinth 20 and extends downwardly adjacent to thettube 24 and the thermostat 28. The stirrer 30 is connected to a motor 32 which is arranged to be energised for the same period as the apparatus 10 remians energised, the stirrer 30 being thereby rotated to cause a circulation of the ambient fluid (not shown) over the tube 24 and the thermostat 28.

A contact switch 34 is connected to the upper surface of the plinth 20 and has an operating button 36 which projects through yet a further aperture (not shown) in the plinth 20 and is located below the lower level of the plinth. The button 36 is arranged to be contacted by a container 38 when the latter is pushed upwardly over the tube 24, the stirrer 30 and the thermostat 28 to press the switch into an on position. The switch 34 is arranged to supply electrical energy from the mains supply (not shown) to the apparatus 10 to energise the latter when the switch is in the on position. The button 36 is urged downwardly into the inoperative position when the container is disengaged therefrom, the button moves downwardly so that the switch 34 returns to an off position causing the apparatus 10 to be de-energised.The operation of the switch 34 thus conserves energy since the apparatus 10 is not energised all of the time but only when the container is placed in contact with the switch.

The container 38 is a closed vessel having a sealing cap 40 in the top surface 42 thereof which can be removed to expose an opening (not shown) through which the tube 24, the stirrer 30 and the thermostat 28 can be inserted into the container 38. The container is formed of stainless steel but has an insulated lining therein to restrict the passage of heat into the container.

A tap 44 is secured to the lower portion 46 of the container and the tap can be operated so as to dispense from the container 38 any fluid contained therein. The tap 44 is nor mally retained in a close position so that no access to the interior of the container 38 is provided except through the opening (not shown) by removal of the sealing cap 40.

A downwardly depending hook 45 is formed one at each side of the container 38, and each hook 45 is arranged to be releaseably secured to an associated catch mechanism 47 located one on each side of the plinth 20. Each catch mechanism 47 comprises a latch 48 which has an upturned end portion 50 arranged to engage under a respective one of the hooks 45, and a spring 52 which urges the latch 48 inwardly towards a respective side of the plinth 20. The arrangement is such that when the sealing cap 40 is removed from the container 38 and the container is pushed upwardly relatively to the apparatus 10 so that the tube 24, the thermostat 28 and the stirrer 30 pass through the opening (not shown) and into the container, each latch 48 is urged outwardly against the action of its associated spring 52 by a hook 45 until the upturned end of the latch passes below the hook 45.The latch is then urged to engage under the associated hook 45 by its spring 52 so that each hook 45 becomes releaseably engaged on a respective latch 48.

When the container 38 is released, its own weight forces down each hook 45 relatively to the associated latch 48 causing engagement of each hook 45 and latch 48 to ensure that the container is then releaseably secured to the plinth 20. The container 38 can however be released from the plinth 20 by pushing the container upwardly relatively to the plinth 20 to disengage the upturned portion of each latch 48 from its associated hook 45 and then pulling the container 38 down and away from the plinth 20 whilst each latch 48 is held outwardly from its respective side of the plinth 20 against the action of the associated spring 52.

The container 38 may contain milk (not shown) and when it is required to cool the milk, the sealing cap 40 on the container 38 is firstly removed. The hooks 45 on container 38 is then brought into engagement with the latches 48 in the plinth 20 as previously described, to releaseably secure the container to the plinth whilst at the same time the tube 24, the thermostat 28 and the stirrer 30 are inserted through the opening (not shown) at the top 42 of the container 38 and into the milk confined within the container. As the container 38 is releaseably secured to the plinth 20, its top surface 42 engages with the button 36 of the switch 34 to thereby energise the refrigeration apparatus 10. The tube 24 therefore becomes cooled and the milk (not shown) in contact therewith is thus also chilled.The stirrer 30 rotates to circulate the milk (not shown) to promote an even temperature throughout the milk. The thermostat 28 responds to the temperature of the milk which it is in contact with, to control the refrigeration operation so as to thereby maintain the tube 24 and therefore the milk, at a predetermined temperature.

The milk (not shown) in the container can thus be maintained at a relatively low temperature by the refrigeration apparatus 10 until it is required to dispense the milk from the container 38, at which time the tap 44 is opened to allow the milk to flow from the container. When sufficient milk has been dispensed, the tap 44 is again closed. The milk remaining in the container 38 can still be maintained at the predetermined temperature by the apparatus 10, if desired.

It will be appreciated that the refrigeration apparatus could form a necessary part of a system of food or drink distribution such as, for example, the delivery of milk to the public.

A refrigeration apparatus according to the invention could be installed one in each home of a number of customers requiring a delivery of milk. A suitable container of milk once having been delivered to each customer could then be secured each one to a respective refrigeration apparatus in order that the milk container therein can be maintained at a temperature at which it will remain fresh for a number of days until the next delivery of milk is to take place. The container used for such a delivery system could of course be one in accordance with the invention as mentioned above, the container being either returned to a dairy for cleaning and later refilling with milk, or being retained and cleaned by the customer and refilled at the customers home when each delivery of milk takes place.

Although the refrigeration apparatus can be used, and is throught to be ideally suitable, for a system of food or drink distribution as described above, it is also envisaged that the apparatus in accordance with the invention will be useful for many other purposes. If the apparatus 10 is used to cool wine, for example, the apparatus 10 may be arranged to cool the wine at any desired temperature in the range 1 6 to 4 degrees centigrade.

Turning now to Fig. 2 of the accompanying drawings, there is shown therein a probe 54 which can be used to replace the probe 1 9 of the refrigeration apparatus 1 0. The probe 54 comprises an evaporator 56 which, like the evaporator 1 8 takes the form of a stainless steel U-shaped tube 58. Each of the arms of the tube 58 extends through an associated aperture 60 formed through the plinth 20 part of which is shown in Fig. 7. The tube 58 is coiled at 62 so that the area of the tube available for heat transfer is increased.

The portion of the tube 58 which extends below the plinth 20 is housed in a substantially cylindrical open-topped stainless steel flask 64. The flask 64 has a flange 66 extending around its upper end and a series of holes 68 are formed through the flange 66.

The holes 68 are each registered with an associated hole 70 formed through the plinth 20. The flange 66 secured to the plinth 20 by means of bolts 72, each bolt 72 passing through a hole 70 and the associated hole 68 and being tightened onto a nut 74 threaded on the free end thereof.

The outer surface of the coiled arm 62 of the tube 58 is flattened and is in intimate contact with portions of the internal surface of the flask 64 as shown in Fig. 2 to enhance conductive heat transfer between the tube 58 and the flask 64.

A motor 76 is housed in the lower end of the flask 64 below the tube 58, and the motor 76 is arranged to cause vibration of the flask 64 when energised. The motor 76 is intended to replace the motor 32 and stirrer 30 and the motor 76 is arranged to be energised for the same period as the apparatus 10 remains energised.

A conduit 78 is connected to the motor 76 and the conduit extends upwardly between the arms of the tube 58 and through a central hole 80 formed through the plinth 20. The conduit 78 houses a pair of electrical wires 82 which are connected to the motor 76 and are arranged to carry electrical energy thereto when the motor is energised. The conduit 78 also houses a thermostat 84 which like the thermostat 28, is arranged to energise the refrigeration apparatus 10 in response to the temperature sensed by the thermostat in the conduit 78 to maintain the probe 54 at a substantially constant temperature, the latter temperature being preset by regulating the temperature at which the thermostat 84 energises the refrigeration apparatus 10.

The flask 64 is filled with an antifreeze solution 86 which is sealed within the flask 64 between the motor 76 and the plinth 20, and the anti-freeze solution 86 is capable of being maintained at a low temperature by the evaporator 56 without freezing.

When the evaporator 58 and themostat 84 are coupled to the refrigeration apparatus 10 in place of the evaporator 18 and the thermostat 28, and a container 38 is secured to the apparatus 10 as previously described with reference to Fig. 1 with the probe 54 passing through the opening (not shown) in the top surface 42 of the container 38, the button 36 of the switch 34 is actuated to cause energisation of the refrigeration apparatus 10 and of the motor 76.

The thermostat 84 controls the operation of the apparatus 10 to maintain the evaporator 58 at a substantially constant predetermined low temperature. Heat is transferred to the evaporator 58 from the surrounding antifreeze solution 86 and from the flask 64 and as a result the solution 86 and flask 64 are maintained at a substantially constant low temperature which is of slightly higher value than the constant low temperature of the evaporator 58. Fluid (not shown) such as milk, housed in the container 38 is cooled by the probe 54 as heat is transferred from the fluid through the flask 64 and the solution 86 to the evaporator 56. Also, the vibrations induced in the flask 64 by the motor 76 are transmitted to the fluid (not shown) in the container 38 and cause agitation of the fluid so as to enhance the heat transfer between the fluid and the probe 54.

Alternative embodiments according to the invention are also envisaged, thus, for example, a sealing means could be provided on the plinth 20 or on the container 38 to seal around the opening (not shown) of the container once the tube 24, the thermostat 28 and the stirrer 30, or the probe 54 have been inserted into the container.

The container 38 could be replaced by an open-topped container the open-top of which could be sealed around the plinth to restrict the passage of warm air into the replacement container. Also, the container could be formed of materials other than stainless steel such as, for example a plastics material or a corrosion resistant metal.

It will be appreciated that side walls, and end walls could be provided on the plinth 20 upstanding therefrom to enclose the apparatus 10 on the plinth, to form a cabinet for the apparatus 10 whilst the tube 24 projected downwardly from the cabinet.

The working fluid could comprise a liquid or a liquified gas and may, for example, comprise liquified ammonia, ethylchloride, freon or the like refrigerant. Also, although the refrigeration operation described above is a compression refrigeration process, it will be understood that the refrigeration apparatus 10 could alternatively operated by means of an absorbtion refrigeration process having, for example, ammonia vapour as the working fluid.

If required, the paddle stirrer 30 or the motor 76 could be dispensed with since the fluid in the container would tend to flow around the probe 1 9 or 54 during a refrigeration operation owing to convective circulation currents set up in the fluid. Also, the antifreeze solution 86 of the probe 54 could be replaced by a similar fluid having a low freezing point temperature.

Claims (23)

1. Refrigeration apparatus having a probe projecting outwardly therefrom, the refrigeration apparatus being operable to cool the probe and the probe being insertable into a container to cool any contents of the container.

2. Refrigeration apparatus as claimed in Claim 1, having a switch arranged to switch the refrigeration apparatus on when the probe is inserted into a container.

3. Refrigeration apparatus as claimed in Claim 2, in which the switch is arranged to engage with, and be operated by the container, the switch being switched off again when the probe is removed from the container.

4. Refrigeration apparatus as claimed in any one of the preceding claims, having an agitation means arranged to agitate the contents of a container once the probe has been inserted into the container.

5. Refrigeration apparatus as claimed in Claim 4, in which the agitation means comprises a paddle stirrer or a vibration means.

6. Refrigeration apparatus as claimed in any one of the preceding claims, in which the refrigeration apparatus is provided with mounting means for securing the apparatus to a wall or the like surface.

7. Refrigeration apparatus as claimed in any one of the preceding claims, in which the refrigeration apparatus is provided with fastening means arranged to releaseably secure to the refrigeration apparatus a container in which the probe has been inserted.

8. Refrigeration apparatus as claimed in any one of the preceding claims, in which sealing means is provided to seal around an opening of the container in which the probe has been inserted, to restrict the passage of air, moisture or the like into, or from the container.

9. Refrigeration apparatus as claimed in any one of the preceding claims, in which the probe comprises a tube.

10. Refrigeration apparatus as claimed in Claim 9, in which the refrigeration apparatus is arranged to supply refrigerant to the tube.

11. Refrigeration apparatus as claimed in Claim 10, in which the tube is looped and/or coiled so that the refrigerant can be recirculated back to the refrigeration apparatus.

12. Refrigeration apparatus as claimed in any one of the Claims 9, 10 or 11, in which the tube is formed of stainless steel to inhibit the corrosion thereof, and to facilitate cleaning of the tube.

1 3. Refrigeration apparatus as claimed in any one of the preceding claims, in which the refrigeration apparatus is thermostatically controlled.

1 4. Refrigeration apparatus as claimed in any one of the preceding claims, further comprising a container arranged to receive the probe, the container being releaseably securable to the refrigeration apparatus.

1 5. Refrigeration apparatus as claimed in Claim 14, in which the container is formed of stainless steel or the like corrosion resistant material which can be easily sterilised or otherwise cleaned.

1 6. Refrigeration apparatus as claimed in Claim 14, or Claim 15, in which the container is insulated so as to reduce the transfer of heat from the environment to the container or its contents.

1 7. Refrigeration apparatus as claimed in any one of Claims 14, 15 or 16, in which the container has a dispenser arranged to dispense the contents of the container therefrom.

1 8. Refrigeration apparatus as claimed in Claim 17, in which the dispenser comprises a tap.

1 9. Refrigeration apparatus as claimed in any one of Claims 14 to 18, in which the container is sealable when removed from the refrigeration apparatus so that the contents thereof can be isolated within the container.

20. Refrigeration apparatus as claimed in any one of the Claims 14 to 19, in which the container has a resealable aperture through which the probe can be inserted.

21. Refrigeration apparatus as claimed in any one of Claims 14 to 20, in which the container is provided with a sealing means to seal around the probe as the probe is inserted into, or withdrawn from the container and/or when the container is releasably secured to the refrigeration apparatus.

22. Refrigeration apparatus constructed arranged and adapted to operate substantially as herein described with reference to the accompanying drawings.

23. Refrigeration apparatus as claimed in Claim 22, and as illustrated in the accompanying drawings.