AUTOMATIC COLD TREATMENT

Field of the Invention

[0001] This invention relates generally to a system and method for applying automatic temperature control, and in particular, to a system and method of providing automatic temperature control to apply cold treatment to harvested produce, such as fruit or vegetables, that is typically being transported between different jurisdictions.

Background of the Invention

[0002] Generally, a destination jurisdiction, such as a destination country, requires that a cold treatment protocol (procedure) be applied to harvested produce, such as fruit or vegetables, before that produce is allowed to be imported and sold within the destination country. Typically, a cold treatment protocol includes criteria a cold and controlled temperature be applied to a quantity of produce, for a period of time, in order to rid the produce of problems associated with insects that could be infest the produce prior to being cold treated. The cold and controlled temperature is typically near or below the temperature at which water freezes, namely 32 degrees Fahrenheit (0 degrees Centigrade). The criteria are expressed as a set of operating procedures and rules, depend not only on the type of produce being cold treated, but also depend on the identity of the source jurisdiction (country) from which the harvested produce is being transported from.

Summary of the Invention

[0003] A system and method of providing reliable and energy efficient automatic temperature control for the purpose of applying cold treatment to harvested produce that is being transported between a source and a destination jurisdiction. The method includes steps that iteratively transition between declining cooling temperatures and that iteratively transition between difference sets of cold treatment criteria (operating procedures and rules) in pursuit of a compliance with a cold treatment protocol required by a particular destination jurisdiction.

[0004] The foregoing as well as other objects, aspects, features, and advantages of the invention will become more apparent from the following description and from the claims.

Brief Description of the Drawings

[0005] The objects and features of the invention can be better understood with reference to the claims and drawings described below. The drawings are not necessarily to scale and the emphasis is instead generally being placed upon illustrating the principles of the invention. Within the drawings, like reference numbers are used to indicate like parts throughout the various views. Differences between like parts may cause those like parts to be each indicated by different reference numbers. Unlike parts are indicated by different reference numbers.

[0006] FIG. 1 is an illustration of an embodiment of a container including an internal cavity, a temperature monitoring and control device, a quantity of harvested produce and a plurality of temperature sensing devices.

[0007] FIG. 2A is a flow chart that illustrates an embodiment of a method of cold treatment that iteratively transitions to lower cooling temperatures in pursuit of compliance with a particular cold treatment protocol.

[0008] FIG. 2B is a flow chart that illustrates the method of FIG. 2A that iteratively transitions to different sets of cold treatment criteria (sets of rules) after an attempt to apply a first set of cold treatment criteria (operating procedures and rules) has failed.

Detailed Description of the Invention

[0009] FIG. 1 is an illustration of an embodiment of a container 110 including an internal cavity 112, a temperature monitoring and control device 120, a quantity of produce 114 and a plurality of temperature sensing devices 118a- 118d. As shown, the produce 114 is disposed on one or more pallets 116. The temperature sensing devices 118a- 118d are each disposed adjacent to one or more items (pieces) of produce 114 and/or are disposed at least partially inside of an item (piece) of produce 114. The produce is also referred to as a cold treatment target.

[00010] The temperature monitoring and control device 120 is configured to output a flow of cold (temperature reduced) air within the internal cavity 112. The cold air functions as a coolant. As shown, the cold air flows from the device 120 and flows down along a near wall 124a and under the produce 114 by entering and flowing through a near side 126a of the pallets 116 and continuing to flow under the pallets 116 and continuing to flow up and out from under a far side 126b of the pallets 116 and then flowing up along a far wall 124b and flowing above and around the produce 114 and back towards the device 120. [00011] The pallets 116 are configured to provide passage of flowing air from the near side 126a to the far side 126b of the pallets. Some of the flowing air below the pallets 116 flows up from the pallets 116 and into the produce 114. The flowing air flows (circulates) within the cavity 112 and returns back to the device 120 and the device 120 inputs, re-cools and re-outputs the flowing air to re-circulate the flowing air within the internal cavity 112. [00012] Each of the temperature sensing devices 118a- 118d is configured to measure a temperature proximate (local) to each respective device 118a-l 18d and is configured to communicate the proximate (local) temperature measurements to the temperature monitoring and control device 120. Each of the temperature measurements are communicated via a communications channel (not shown) that connects each respective device 118a-l 18d to the temperature monitoring and control device 120. In some embodiments, a communications channel (not shown) is provided for each device 118a-l 18d. Preferably, the temperature measurements are communicated near simultaneously (in real time) to the device 120. [00013] The temperature monitoring and control device 120 is configured to input local temperature measurements and to perform actions based upon those local temperature measurements. In some embodiments, the device 120 includes a processor (CPU) and software stored in memory (not shown). The software is configured to control the behavior of the device 120.

[00014] In some embodiments, the software inputs and processes a data set (not shown) that includes information that describes a particular set of automated cold treatment rules. The automated cold treatment rules are typically required by a particular international jurisdiction. For example, a first data set can describe a first set of automated cold treatment rules and a second data set can describe a second set of automated cold treatment rules. Hence, in one scenario, processing of the first data set performs the first set of automated cold treatment rules. Alternatively, processing the second data set performs the second set of automated cold treatment rules.

[00015] Generally, an international jurisdiction, such as a country, also referred to as a destination country, requires a particular cold treatment protocol (procedure) to be applied to produce, such as fruit or vegetables, before that produce is allowed to be sold within the country. Typically, a cold treatment protocol requires that a cold and controlled temperature be applied to a quantity of produce, for a period of time, in order to rid the produce of problems associated with insects that could infest the produce. The cold and controlled temperature is typically near or below the temperature at which water freezes, namely 32 degrees Fahrenheit (0 degrees Centigrade).

[00016] A specific cold treatment protocol may depend not only on the type of produce, but also depends on the identity of the jurisdiction (country), also referred to as the source country, that is the source of the particular type of produce being shipped to the destination country

[00017] For example, the United States requires grapes being transported from Peru to be cold treated with a 35 degree F temperature for 17 consecutive days. In another example, China requires that citrus being transported from Peru to be cold treated with a 0.5 degree Centigrade temperature for 15 days.

[00018] In some circumstances, a jurisdiction (country) may allow an importer to select one of a plurality of cold treatment options. In one hypothetical example scenario, a country requires that particular produce being imported from a particular country be cold treated with a 5 degree F temperature for 15 days, or at 0.0 degree F temperature for 12 days or at a -5 degree F temperature for 9 days.

[00019] Typically, cold treatment is performed aboard a ship transporting produce and in transit between a source country and a destination country. A transit schedule for a ship may or may not allow for 15 days to perform a cold treatment procedure, but may allow for 9 or 12 days to perform a cold treatment procedure. The energy costs to lower the temperature of a container to -5 degrees F are higher than the energy requirements to lower the same container to a temperature of 0 degrees F. Likewise, the energy costs to lower the same container to a temperature of 5 degrees F are higher than the energy requirements to lower the same container to a temperature of 0 degrees F or -5 degrees F.

[00020] When not being actively cooled, the container 110 will have a temperature approximating that of ambient (atmospheric) temperature. When being actively cooled to a target temperature below that of ambient temperature, the active cooling extracts heat from the container 110 and transfers the heat to the atmosphere. In parallel with the active cooling,

in response to the difference in temperature between the container and the atmosphere, heat (energy) naturally transfers from the atmosphere to the container. To compensate for heat transfer from the atmosphere to the container when the container 110 is being cooled below ambient temperature, coolant having a cooling temperature below that of the target temperature is supplied to the container. Typically, the cooling temperature is at least 0.5 degree F below that of the target temperature.

[00021] Generally, the lower the cooling temperature of the supplied coolant, the more energy is required to supply the coolant at that lower cooling temperature. Hence, the higher the cooling temperature of the supplied coolant, the less energy is required to supply the coolant to the container.

[00022] As a consequence, depending upon the quantity of time and energy required to perform a cold treatment procedure onboard a ship transporting produce between a source jurisdiction (country) and a destination jurisdiction (country), one of a plurality of cold treatment procedures may be more advantageous (desirable) than another of the plurality of cold treatment procedures required by a destination jurisdiction (country), for a particular set of circumstances.

[00023] FIG. 2A is a flow chart that illustrates an embodiment of a method of cold treatment that iteratively transitions to lower cooling temperatures in pursuit of compliance with a particular cold treatment protocol.

[00024] The method includes a first step 210 that performs identifying a cold treatment protocol expressed as a first set of cold treatment operating parameters. The first set of operating parameters is in accordance with a first cold treatment protocol (procedure) for a particular jurisdiction (country). For example, the first cold treatment procedure can employ a first target temperature parameter of -5 degrees F and a first waiting period parameter of 9 days, also referred to as a first waiting period of time. The aforementioned -5 degree F temperature and the 9 day waiting period constitute a hypothetical example of a set of cold treatment protocol parameters. In actual practice, the values of cold treatment protocol parameters vary widely. Embodiments of the invention are designed to be programmable so that any of the wide variety of cold treatment protocol parameters can be carried out according to those parameters by the invention.

[00025] The next step 212 performs supplying coolant at a first cooling temperature.

For example, the first cooling temperature is equal to (-6 degrees F) which is equal to the target temperature (-5 degrees F) minus a temperature offset (0.5 degrees F), in an attempt to reduce the temperature of the cavity within the container 110 to -5 degrees F.

[00026] The next step 214 determines whether any of the temperature sensing devices

118a-l 18d are reporting a local temperature, also referred to as a current waiting period temperature, greater than a target (maximum limit) temperature (-5 degrees F) minus the temperature offset (0.5 degree F). For this example, the temperature offset equals 0.5 degrees

F. If true 216, meaning that the target temperature minus the temperature offset equal to 0.5 degrees F has not yet been reached, then coolant at a first cooling temperature continues to be supplied to the container 110.

[00027] If false 218, meaning that all current waiting period temperatures are equal to or below the target temperature minus the temperature offset equal to 0.5 degrees, then a first waiting period timer is started 220. In accordance with this first set of rules for this hypothetical example, the first waiting period timer is set to expire (alarm) after 9 days.

[00028] The next step 222 determines if the first waiting period timer has expired. If true 224, then a post cold treatment procedure step 226 is performed and this method terminates via a first path of completion 228.

[00029] If false 230, the next step 232 determines if any of the temperature sensing devices 118a- 118d are reporting a local temperature greater than a target (maximum limit) temperature minus the temperature offset equal to 0.5 degrees F.

[00030] If false 234, then coolant at the first cooling temperature continues to be supplied to the container 110 and the step 222 of determining if any of the temperature sensing devices are reporting a local temperature greater than a target (maximum limit) temperature minus the temperature offset is re-performed. If false 234, then none of the current waiting period temperatures are classified as approaching the maximum limit temperature.

[00031] If true 236, at least one of the current waiting period temperatures are classified as approaching the maximum limit temperature. If true 236, then the next step 238 determines whether coolant at a further reduced cooling temperature, colder than the first cooling temperature, can be supplied to the container 110.

[00032] If yes 239, then coolant at a further reduced cooling temperature is supplied

240 to the container 110 and step 242 transitions to and re-performs step 214. For example, the further reduced cooling temperature equals -7 degrees F. Optionally, in some embodiments, a temperature reduction waiting period expires before the step 232 is re- performed. For example, the temperature reduction waiting period can be equal to 1 hour. [00033] When step 232 is re-performed, if at least one of the current waiting period temperatures are approaching (rising to) the maximum limit temperature, then step 238 is re- performed to determine if coolant can be supplied at a further reduced cooling temperature. [00034] If false 244 (no coolant can be supplied at a further reduced cooling temperature) and the current further reduced cooling temperature is the furthest reduced cooling temperature that can be supplied. Then step 246 is performed to determine if any if the current waiting period temperatures exceed the first maximum limit temperature equal to -5 degrees F.

[00035] If false 249, then the coolant at a furthest reduced cooling temperature continues to be supplied and step 222 is re-performed while the current waiting period temperatures are less than the first maximum limit temperature for and until a remaining portion of the first waiting period of time has elapsed, constituting a second path of completion according to the first set of rules.

[00036] Otherwise, if true 248, then step 250 is performed as fully illustrated in FIG.

2B. Step 250 searches for other cold treatment rules permitted by the destination jurisdiction. [00037] FIG. 2B is a flow chart that illustrates the method of FIG. 2A that iteratively transitions to different sets of cold treatment criteria (sets of rules) after an attempt to apply a first set of cold treatment criteria (rules) has failed.

[00038] Step 250 searches for another (second) applicable set of cold treatment criteria

(rules and operating parameters) requiring another (second) maximum limit temperature to be applied to a cold treatment target for a second waiting period of time. Further, this search 250 searches for a second maximum limit temperature that is greater than or equal to the highest current temperature reported from the temperature sensing devices. [00039] If another applicable set of rules is found 254, then the timer is modified 260 in accordance with the waiting period of the other found applicable set of rules. For example, if the first waiting period of the first applicable set of rules is 9 days and the length of the

another found waiting period is 12 days, then (12-9) = (3) days are added to the current time remaining on the timer for the current waiting period, also referred to as the remainder of the current (first) waiting period. The timer is also referred to as the current waiting period timer. [00040] Else if another applicable set of rules is not found 256, then this procedure is aborted 272, meaning that the procedure is terminated (aborted) before it can be completed successfully. This procedure is aborted because despite the fact that coolant having the furthest reduced cooling temperature is being supplied, the highest (least restrictive) maximum limit temperature for all applicable sets of rules cannot be maintained for the entire waiting period of this cold treatment procedure. Optionally, an alarm is activated. Optionally, the container can be maintained at a predefined cargo set point temperature hereafter until further action is taken by associated personnel.

[00041] The next step 262 determines if the current waiting period timer has expired.

If true 264, then a post cold treatment procedure step 266 is performed and this method correctly terminates via a first path of completion 266 according to another set of cold treatment rules.

[00042] Else if the current waiting period timer has not expired 263, then the next step

270 determines whether the highest current temperature reported by the temperature sensing devices is greater than the current maximum limit temperature.

[00043] If not true 265, then the steps 262 and 270 are re-performed in a cyclic fashion until the timer expires or the highest current temperature reported by the temperature sensing devices is greater than the current maximum limit temperature.

[00044] Else if true 267, then step 250 is re-performed to search for another applicable set of rules permitting another maximum limit temperature and where the maximum limit temperature of the another set of rules is greater than or equal to the highest current temperature reported from the temperature sensing devices. If no other set of rules is found 256, the procedure is aborted (see step 272) as explained above.

[00045] While the present invention has been explained with reference to the structure disclosed herein, it is not confined to the details set forth and this invention is intended to cover any modifications and changes as may come within the scope and spirit of the following claims.