Refrigeration unit temperature alarm using thermal properties of food to eliminate false alarms

Abstract

A temperature sensing system for refrigeration and related methodology. The system has a refrigeration unit containing one or more food products, a temperature sensor disposed in the refrigeration unit. The temperature sensor is in communication with a remote computing device that is configured to calculate thermal data pertaining to said one or more food products. The remote computing device in communication with a temperature monitor that receives real-time temperature information from the temperature sensor. The monitor includes an alarm function that is activated if temperature inside said refrigeration unit causes a rise of the actual product temperature above a specified threshold such as 41° F. while noting the time remaining to return the product temperature to a safe level within the government specified 4 hour limit.

Claims

1. A method for sensing the temperature of a refrigeration unit, comprising: providing said refrigeration unit having an initial inside temperature below a threshold value; providing one or more food products into said refrigeration unit; providing into said refrigeration unit a temperature sensing unit, wherein said temperature sensing unit measures inside air temperature of said refrigeration unit; establishing a communications link between said temperature sensing unit and a remote computing device, wherein said computing device is configured to determine thermal properties of said one or more food products; transmitting from said temperature sensing unit to said remote computing device, temperature data corresponding to said inside air temperature of said refrigeration unit; upon detection by said temperature sensing unit of a temperature above said threshold value, determining on said computing device based on said thermal properties, time needed for said one or more food products to spoil; determining on said computing device based on said thermal properties, time needed for said one or more food products to return to said threshold value; and providing an alarm signal if said computing device determines that said time needed for said one or more food products to spoil is less than time needed for said one or more food products to return to said threshold value.

2. The method of claim 1, wherein said temperature sensing unit includes a transmitter comprising a network adapter.

3. The method of claim 1, wherein said computing device comprises a central processing unit, a database, and a computer program.

4. The method of claim 1, wherein said thermal properties are determined based on discharge air temperature of said refrigeration unit, specific heat of said food product, bulk density and moisture content of said food product, heat transfer coefficient of said food product, time intervals, surface area of aid food product, the volume of said food product, and combinations thereof.

5. The method of claim 1, including the step of: activating an alarm if the temperature inside the refrigeration unit causes a rise of a selected actual product temperature above a specified threshold such as 41° F. while noting the time remaining to return the actual product temperature to a safe level within a specified time limit.

Description

BRIEF DESCRIPTION OF THE DRAWING

(1) FIG. 1 shows a schematic diagram of the system in accordance with the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT OF THE INVENTION

(2) Referring now to the drawing and in particular FIG. 1, one embodiment of the overall system 10 is shown. Included is a refrigeration unit 12 that has contained therein a specific food package 14 that is being refrigerated and a temperature sensor 16 that monitors the real-time temperature inside the refrigerator 12. The temperature sensor 16 can send a wireless signal of actual temperature data to a local area network or supplied access point 18. The temperature data is transmitted over the Internet 20 to a remote computing device 22 having a server 24, and a central processing unit (CPU) 26 containing a database and a computer software program 28 that calculates thermal data of the specific food product 14. The computing device 22 is also attached to the Internet 30 which is connected to a customer computer 32 that includes a monitor 34 that can receive real-time information concerning the food product 14 contained in refrigeration unit 12. The monitor 34 also includes an alarm function to alert the user of a critical temperature variation that requires action.

(3) In some embodiments, the specific food product 14 in the refrigeration unit 12 is selected to be the worst-case scenario and most sensitive food product contained in the refrigeration unit 12 for the computer program analysis of its thermal properties. This assures a bottom-line fail safe for the system, by monitoring and regulating the temperature of the most sensitive food product. In some embodiments, the refrigeration unit 12 contains only one type of food product 14 and, therefore, the system is programmed for the temperature and condition requirements of that single food product. Computer program 28 includes information corresponding to the thermal properties of the specific food product 14 in order to calculate food temperatures while the food product is in the refrigeration unit 12. The computer program 28 analyzes variables including discharge air temperature of the refrigeration unit, specific heat of the food product, bulk density and moisture content of the product, heat transfer coefficients, time intervals, surface area of the specific food product 14 and packaging, and the volume of the specific food product 14.

(4) The computer program 28 and databases calculate and assign alarm data based on the actual real-time temperature and any temperature change inside the refrigeration unit to determine whether or not there is a danger of food spoilage. The computer program 28 also calculates an important temperature of the specific food product 14 that will determine a period of time for specific food product 14 temperature to reach a different temperature. This process analyzes discharge air temperature and the other variables mentioned including the humidity and the rate of change of temperature variation. The purpose is to determine the amount of time it would take the food product 14 to reach a temperature that has changed inside the refrigeration unit 12. To wit, if the temperature inside the refrigeration unit 12 increases to a particular temperature above a threshold value, the computer program 28 will calculate the time that it would take the food product 14 to reach a spoilage temperature and a period of time to correct the temperature. If the time to reach spoilage is less than the time needed to correct the temperature, the system will trigger the alarm in the monitor 34 of the customer computer 32. Thus, it is also necessary to determine when a food product temperature goes above a threshold value, such as 41° F., to determine how long it will take for the specific food product 14 to return to 41° F. With knowledge of this calculation that is provided by the computer program, the system can inform an operator if the system is too far out of the temperature range to have enough time to correct the temperature for the specific food product 14 to avoid spoilage. Essentially it would take too long to correct the temperature for the food product 14 to remain at a safe temperature indicating that the operator must use or discard the food product 14.

(5) The present invention contemplates various embodiments of a method regulating the temperature inside the refrigeration unit and providing an alarm if a spoilage condition is to occur. First, a refrigeration unit having an inside temperature below a threshold value is provided. Next, food is provided in the refrigeration unit. In some embodiments, the food is homogenous. In other embodiments, a plurality of types of food with different temperature characteristics is provided. Next, a temperature sensing unit is provisioned, wherein the temperature sensing unit can measure the inside air temperature of the refrigeration. The temperature sensing unit further includes a transmitter, such as a network adapter, to transmit temperature data to a local area network that, in some embodiments, is connected to the Internet. The temperature data is passed through to a computer server that includes a central processing unit (CPU), a computer program, and a database wherein the computer program is configured to execute calculations of the thermal properties of the specific food maintained in the refrigeration unit based on the discharge air temperature, specific heat of the food product, bulk density of the food product, moisture content of the food product, heat transfer coefficient, time intervals, time variation, rate of change, humidity, surface area of the food product package, and volume of the food product package. In some embodiments, the calculations executed by the computer program determine a measurement of the time it would take the food product to reach a temperature that has changed inside the refrigeration unit.

(6) After determining the time it will take for the food product to reach the new temperature of the refrigeration unit, the computer program will conduct an analysis of the temperature inside the refrigeration unit as it increases to a particular temperature in order to calculate the time that the specific food product will reach a spoilage temperature. The computer program will then determine when a food product temperature goes above the threshold value to determine how long it will take the food product to return to the threshold value or below. Finally, the computer program will provide an alarm signal to the user if the system variables exceed the safe limit of preserving the food product if the temperature change within the refrigeration unit is beyond the threshold value.

(7) The computer program and databases can generate alarm information based on actual real-time refrigeration unit temperature to determine whether there is a realistic danger of food spoilage to avoid false alarms. The alarm generated information is based on real-time temperatures within a refrigeration unit for a specific food product and will be set off if the computer program and system determine that the time to reach spoilage is less than the time needed to correct the temperature inside the refrigeration unit.

(8) The system and method described herein for protecting food from spoilage requires only a real-time temperature reading inside a specific refrigeration unit and the information described above to determine the parameters of a specific food product and its packaging. In a case with multiple different food products in one refrigeration unit, the worst-case scenario can be used for the most sensitive food product when determining whether or not to sound an alarm based on temperature variations in a refrigeration unit that exceed threshold values of the worst-case scenario which would indicate a problem that could cause spoilage.

(9) The computing systems described herein, such as the CPU 26, servers, and workstations may include a central processing unit (CPU) having a conventional microprocessor, random access memory (RAM) for temporary storage of information, and read only memory (ROM) for permanent storage of “read only” information. A memory controller is provided for controlling system RAM. A bus controller is provided for controlling a data bus, and an interrupt controller is provided for receiving and processing various interrupt signals from the other system components. Data storage may be provided by known non-volatile, removable media storage drives, such as a diskette drives, DVD drives, CD-ROM drives, flash drives, magneto-optical (“MO”) drives, and the like, or by non-removable storage systems like hard drives. Data and software may be exchanged with the computing systems via removable media, such as CD-ROMs, DVDs, MO disks, flash drives and the like. The removable media is insertable into a compatible removable media storage drive, which, in turn, utilizes a controller to interface with the data bus. The non-removable storage system is part of a fixed disk drive, which utilizes a hard drive controller to interface with the data bus. User input to the computer may be provided by a number of devices. Examples include a keypad, a keyboard, a mouse, and a trackball, which may be connected to the data bus by an input controller. A direct memory access (DMA) controller is provided for performing direct memory access to system RAM. A visual display may be generated by the graphics subsystem of the computing system that controls the display device attached to the computing system. The display device can be a conventional cathode ray tube (“CRT”), liquid crystal display (“LCD”), light-emitting diode (“LED”), or plasma monitor having individually addressable picture elements (“pixels”.) The pixels are arranged in a two-dimensional X-Y grid and are selectively illuminated, as directed by the graphics subsystem, for assembling an image, or a series of images (or frames) to create moving pictures.

(10) Reference to a network adapter or network communications in this disclosure refers to a network interface device that enables the various computing systems to connect to the described network via a network bus, either wired or wireless. The network, which may be a local area network (LAN), a wide area network (WAN), an electronics communication network, i.e. the Internet, or the like, may utilize general purpose communication protocols that interconnect a plurality of network devices. The computing system is controlled and coordinated by operating system (“OS”) software, such as, for exemplary purposes only, Windows®, Mac OSX, Apple iOS, Linux, Unix, Android OS, PalmOS, Windows Mobile OS, and the like. Among other functions, the OS controls allocation of system resources and performs tasks such as process scheduling, memory management, networking, and I/O services.

(11) While specific embodiments have been described in detail, those with ordinary skill in the art will appreciate that various modifications and alternatives to those details could be developed in light of the overall teachings of the disclosures. Accordingly, the particular arrangements disclosed are meant to be illustrative only and not limiting of the invention, which is to be given the full breadth of the appended claims, and any and all equivalents thereof.