Refrigeration device for regulating temperature of small volume loads

Back

Cooler boxes used to transport vaccines have no constant temperature monitoring system available. The refrigeration devices are bulky and need large amounts of power and space while transportation. This patent describes a lightweight portable refrigeration device to transport temperature sensitive objects using a cooling chamber with a refrigeration mechanism.

About Company

Startup Name	Blackfrog Technologies private limited
Location	Manipal, Karnataka
Patent No.	IN201941013056
Overview	Technology startup company that seeks to improve the efficiency of immunization supply chains. They have developed a patented system for precision cold-chain and vaccine traceability - Emvólio, a portable, battery-powered refrigeration device that will strictly maintain any preset temperature for over 12 hours for last mile transport of vaccines.

Based on patent titled Refrigeration device for regulating temperature of small volume loads published By Blackfrog Technologies private limited

4 Highlights from this Summary

1. Introduction
2. Illustrates the complete portable refrigeration device
3. Cooling chamber
4. Understanding the claims

1 Introduction

see source

Problem Statement: Vaccines are to be kept in a safe cool range of 2 degrees to 8 degrees. Cooler boxes used to transport vaccines in emerging economies have no reliable temperature monitoring systems and are highly unreliable.  Solution: The vaccine vials can be stored in the cooling chamber. The chamber also has a sensor that can detect the presence or absence of a vial. An absorbent at the bottom of the chamber helps absorb any spillage of fluid from the vials. The refrigeration mechanism uses the thermoelectric assembly (TEA). This patent describes a portable refrigeration device that is used to transport items that need regulated temperature control. The device also has a cooling chamber coupled to a refrigeration mechanism.  Key takeaways of the patent: 1. The temperature of the refrigerator is regulated by a proportional integral derivative(PID) controller.  2. This portable refrigeration device ensures the temperature is maintained within the specified range and helps keep the vials at the specified temperature.  3. The device is powered by a rechargeable battery and is economical compared to other bulky refrigeration devices.

2 Illustrates the complete portable refrigeration device

Power switch 11 is used to turn on/off the refrigerator. An LCD display 10 is used to display the temperature level, battery status, vial number and any warnings. Buzzer 16 gives an audible warning when the current parameters are not according to the set parameters

A rechargeable battery 14 is used to drive the whole device and its functionality. The battery is connected to case 13 where all the electronic components like microcontroller, embedded system and PCB are placed.

Vials 8(vaccine vials or any other temperature-sensitive materials) are stored in an acrylic or polypropylene vial holder 6 to hold the vials in position. These vials are stored in the Thermo-Electric Assembly 3 (TEA). A vial holder door 9 is used to seal the cooling chamber.

An illustration of the refrigerator used for storing the vaccine vials or other temperature-sensitive materials.

All the components of the cooling chamber are placed and separated from the surrounding using a casing 12. The temperature sensor 15 senses the internal temperature. The vacuum insulated container 5 is used to store the vaccines.

Show hotspots Large Image

see source

Fig 6 - The casing holds all the components together ergonomically and enables the user to transport the device easily.   The device is powered by a rechargeable battery. It has a rigid flask which forms a cooling chamber and is latched to the thermo-electric assembly. The flask holds items like temperature sensitive vaccine vials, that need a controlled temperature environment.

3 Cooling chamber

Airstream Q ensures there are no hotspots inside the cooling chamber.

Air deflector 24 guides the air from the lower parts of the cold chamber into the vial tray 7. Vial position sensor 26 placed under the vial is used to monitor the temperature and give a warning if the necessary temperature is to maintain in the refrigerator.

Thermal insulation - The head cap holds the TEA in such a manner that the hot side heat sink is held in the head cap in a collar made of thermal insulation

Head cap 1 holds the thermal electric assembly(discussed in highlight 2) with expandable foam for thermal insulation 2.

Acrylic or polypropylene holder is in the space where cooling is provided to the flask 4 by the cold side heat sink.

Flask 4 is screwed Collar P around its periphery separating the hot side heat and the cold side heat sinks. The hot side heat sink 17 is exposed to the surrounding air for heat loss. and the cold side heat sink 18 absorbs the heat from inside and transfers to the other side.

Show hotspots Large Image

see source

Fig 5A  Cooling chamber - Illustrates the fixing of the head cap to the flask and depicts cold air flows  <ol> <li>The refrigeration device maintains load at a constant set temperature in the cooling chamber. The slightest variation from preset temperature will start the Thermo-electric assembly (TEA) </li> <li>The fan in the cold side heat sink starts and circulates cold air over the holder and over the load.</li> <li>The load gets cooled again to the set temperature.</li> <li> The TEA is commanded to shut down based on the inputs from the temperature sensor.</li> <li>The control system proportional integral derivative (PID) is used to maintain the appropriate voltage for the TEA as per the temperature fluctuations inside the cooling chamber. The control loop feedback system modulates the temperature of the cold side heat sink and the speed of the fan and helps in cooling the load</li> </ol>

4 Understanding the claims

Show hotspots Large Image

Claims *Note- All of the claims have been covered in @@h2 and @@h3 1. A refrigerating device, the said device characterized in that comprising: a refrigeration mechanism; and a cooling chamber wherein the cooling chamber is operatively coupled to the refrigeration mechanism using any or a combination of a latching mechanism and a screwing mechanism, and is configured to hold a load to be cooled,  wherein the device includes a proportional integral derivative (PID) controller to set and regulate temperature inside the cooling chamber wherein the device is configured to have total operating weight less than 5 kilograms 2. The device as claimed in claim 1, wherein the said load having at least one vial containing a fluid said vial held in a spaced configured in a said cooling chamber wherein said space is configured with a sensor to detect absence or presence of said at least one vial. 3. The device as claimed in claim 2, wherein the said cooling chamber has an absorbent means at its bottom to absorb any spillage of said fluid from said at least one vial 4. The device as claimed in claim 1, wherein the refrigeration mechanism is a thermo-electric assembly (TEA) 5. The device as claimed in claim 4, wherein said cooling chamber is a flask, open end of said flask configured to thermally sealed with said TEA, wherein said flask provides thermal insulation between said load and ambient environment. 6. The device as claimed in claim 5, wherein said TEA has fan on its cold side heat sink, said fan configured to circulate air in said cooling chamber and over said load. 7. The device as claimed in claim 5, wherein said flask is thermally sealed with said TEA, by configuring the TEA in a collar of thermal insulation, the collar configured  to hold said flask by means of threads configured  on said collar and said flask. 8. The device as claimed in claim 5, wherein said flask is configured to provide said thermal insulation using any or a combination of vacuum and thermal insulation material. 9. The device as claimed in claim 8, where in said device is powered using at least one battery 10. The device as claimed in claim 1, wherein said device having a head cap configured to be attached  on to said refrigeration mechanism commences and wherein said head cap is designed for maximum thermal insulation to said cooling chamber. 11. The device as claimed in claim1, wherein said cooling chamber  has air deflector at its bottom , said air deflector configured to guide air falling on it equally over said load from beneath said load.