EP3394528B1

EP3394528B1 - Safety system for a container having a refrigeration system and method of providing safety

Info

Publication number: EP3394528B1
Application number: EP15828855.5A
Authority: EP
Inventors: Cédric RIVIERE; André STUMPF
Original assignee: Carrier Corp
Current assignee: Carrier Corp
Priority date: 2015-12-22
Filing date: 2015-12-22
Publication date: 2023-08-09
Anticipated expiration: 2035-12-22
Also published as: WO2017109531A1; EP3394528A1

Description

BACKGROUND

The subject matter disclosed herein generally relates to containers having refrigeration systems and, more particularly, to safety systems for containers having refrigeration systems.
Transport refrigeration systems be included and/or incorporated with cargo/shipping containers, trailers, trucks, light commercial vehicles, etc. Each system involves one or more refrigerated compartments and a refrigeration system positioned to cool a recirculating airflow within the compartment or cargo space. Depending upon the implementation, refrigeration equipment may be mounted to an exterior of the container, within a subcompartment in the container, or a combination thereof, e.g., with some components within the compartment and other components mounted to an exterior of the container.
Many truck and trailer configurations mount the equipment to the front of the container, often high on the front wall so that the outlet for discharging cooled air into the compartment is near the compartment ceiling. For a vapor compression refrigeration cycle, the equipment typically includes: an electrically-powered compressor; a heat rejection heat exchanger; an expansion device; and a heat absorption heat exchanger. An internal combustion engine (ICE) generator may also be provided to power the compressor.
The document WO 2015/032905 A1 also discloses a container according to the relevant state of the art.
Thermochemical refrigeration systems may operate in an intermittent fashion or may be operated continuously using parallel loops. The process is based on liquid thermochemical refrigerant (e.g., ammonia) evaporation to a gas which reacts with a medium (e.g., reactive salts). The system has three main elements; an evaporator containing liquid ammonia; a valve; and a reactor containing the reactive salts. These operate in two stages: stage one being a refrigeration stage; and stage two being a recharging or regeneration stage. In a continuous system operation configuration, two parallel flows may be configured with one flow in a refrigeration stage and the other in a regeneration stage, and then switch. The thermochemical refrigerant may be toxic or otherwise hazardous and thus adequately sealed refrigeration systems may be used to prevent leakage of the thermochemical refrigerant into the compartment and/or cargo space. JP 2006 317127 discloses an ammonia abatement method and apparatus including a refrigeration system, an ammonia detection sensor and electric shutters.

SUMMARY

According to one embodiment, a safety system comprising: a container comprising a door wherein the container defines a cargo space; a refrigeration system, wherein at least a portion of the refrigeration system is located at one end of the container and having at least one thermochemical refrigerant; at least one sensor located within the container and configured to detect a presence of the at least one thermochemical refrigerant within an ambient air in the container; a locking mechanism operably configured to automatically lock and seal the door of the container such that persons cannot enter; and a safety controller in communication with the at least one sensor and operably connected to the refrigeration system and the locking mechanism, the safety controller configured to lock and seal the container with the locking mechanism when the at least one sensor detects the presence of the at least one thermochemical refrigerant within the ambient air in the container above a predetermined threshold.
Further embodiments of the system may include that the safety controller is configured to shut off the refrigeration system when the at least one sensor detects the presence of the at least one thermochemical refrigerant within the ambient air in the container above a predetermined threshold.
Further embodiments of the system may include that the at least one thermochemical refrigerant is ammonia.
Further embodiments of the system may include that the at least one sensor comprises a sensor located on a ceiling of the container and a sensor located on a floor of the container.
Further embodiments of the system may include that the locking mechanism is configured to lock and seal a door of the container.
Further embodiments of the system may include that the refrigeration system includes a tank configured to contain the thermochemical refrigerant, the tank located within the container.
Further embodiments of the system may include that the container is a container of a tractor trailer system.
Further embodiments of the system may include that the safety controller is configured to control at least one of a valve or a power supply to the refrigeration system such that when the safety controller shuts off the refrigeration system it prevents fluid flow of the thermochemical refrigerant within the refrigeration system.
Further embodiments of the system may include a notification system configured to provide a notification that the at least one thermochemical refrigerant is present within the container above the threshold.
According to another embodiment, a method of providing safety for a container having a refrigeration system wherein the container defines a cargo space, the method comprising: monitoring with at least one sensor located within the container for a presence of the at least one thermochemical refrigerant within an ambient air in the container; detecting the presence of the at least one thermochemical refrigerant within the ambient air in the container above a predefined threshold; and controlling a locking mechanism to lock and seal a door of the container when the presence of the at least one thermochemical refrigerant within the ambient air in the container above a predetermined threshold is detected.
Further embodiments of the method may include controlling the refrigeration system to shut off the refrigeration system when the presence of the at least one thermochemical refrigerant within the ambient air in the container above a predetermined threshold is detected.
Further embodiments of the method may include that the at least one thermochemical refrigerant is ammonia.
Further embodiments of the method may include that both the locking mechanism and the refrigeration unit are controlled when the presence of the at least one thermochemical refrigerant within the ambient air in the container is detected above the predetermined threshold.
Further embodiments of the method may include that the locking mechanism is configured to lock and seal a door of the container.
Further embodiments of the method may include that the refrigeration system includes a tank configured to contain the thermochemical refrigerant, the tank located within the container.
Further embodiments of the method may include providing a notification that the at least one thermochemical refrigerant is present within the container above the threshold.
Further embodiments of the method may include that controlling the refrigeration system comprising controlling at least one of a valve or a power supply to the refrigeration system such that when the refrigeration system shuts off it prevents fluid flow of the thermochemical refrigerant within the refrigeration system.
Technical effects of embodiments of the present disclosure include a refrigeration safety system configured to detect the presence of a thermochemical refrigerant leak within a container and automatically locking and sealing the container such that persons cannot enter the container. Further technical effects include a refrigeration safety system configured to automatically shut down a refrigeration system when the presence of a thermochemical refrigerant is detected within a container (e.g., outside of a refrigeration system).
The foregoing features and elements may be combined in various combinations without exclusivity, unless expressly indicated otherwise. These features and elements as well as the operation thereof will become more apparent in light of the following description and the accompanying drawings. It should be understood, however, that the following description and drawings are intended to be illustrative and explanatory in nature and non-limiting.

BRIEF DESCRIPTION OF THE DRAWINGS

The subject matter is particularly pointed out and distinctly claimed at the conclusion of the specification. The foregoing and other features, and advantages of the present disclosure are apparent from the following detailed description taken in conjunction with the accompanying drawings in which:

FIG. 1A is a schematic view of an embodiment of a container transportation system having a refrigeration unit and a cargo compartment;
FIG. 1B is a schematic view of an embodiment of a refrigeration unit for a cargo compartment of the container transportation system of FIG. 1A;
FIG. 2 is a schematic view of an container and safety system in accordance with a non-limiting embodiment of the present disclosure; and
FIG. 3 is a flow process of a refrigerated container safety system in accordance with a non-limiting embodiment of the present disclosure.

DETAILED DESCRIPTION

As shown and described herein, various features of the disclosure will be presented. Various embodiments may have the same or similar features and thus the same or similar features may be labeled with the same reference numeral, but preceded by a different first number indicating the figure to which the feature is shown. Thus, for example, element "a" that is shown in FIG. X may be labeled "Xa" and a similar feature in FIG. Z may be labeled "Za." Although similar reference numbers may be used in a generic sense, various embodiments will be described and various features may include changes, alterations, modifications, etc. as will be appreciated by those of skill in the art, whether explicitly described or otherwise would be appreciated by those of skill in the art.
Shown in FIG. 1A is a schematic of an embodiment of a container transportation system 100. The container transportation system 100 includes a tractor 102 including an operator's compartment or cab 104 and also including an engine, which acts as the drive system of the container transportation system 100. A container 106 is coupled to the tractor 102. The container 106 is a refrigerated container 106 and includes a top wall 108, a directly opposed bottom wall 110, opposed side walls 112, and a front wall 114, with the front wall 114 being closest to the tractor 102. The container 106 further includes a door or doors (not shown) at a rear wall 116, opposite the front wall 114. The walls of the container 106 define a cargo compartment. The container 106 is configured to maintain a cargo 118 located inside the cargo compartment at a selected temperature through the use of a refrigeration system 120 located on or next to the container 106. The refrigeration system 120, as shown in FIG. 1A, is located at or attached to the front wall 114.
Referring now to FIG. 1B, the refrigeration system 120 is shown in more detail. The refrigeration system 120 includes a compressor 122, a condenser 124, an expansion valve 126, an evaporator 128, and an evaporator fan 130. The compressor 122 is operably connected to a refrigeration engine 132 which drives the compressor 122. The refrigeration engine 132 is connected to the compressor in one of several ways, such as a direct shaft drive, a belt drive, one or more clutches, and/or via an electrical generator. A refrigerant line 123 fluidly connects the components of the refrigeration system 120.
Airflow is circulated into and through the cargo compartment of the container 106 by means of the refrigeration system 120. A return airflow 134 flows into the refrigeration system 120 from the cargo compartment of the container 106 through a refrigeration unit inlet 136, and across the evaporator 128 via the evaporator fan 130, thus cooling the return airflow 134 to a selected or predetermined temperature. The cooled return airflow 134, now referred to as supply airflow 138, is supplied into the cargo compartment of the container 106 through a refrigeration unit outlet 140, which in some embodiments is located near the top wall 108 of the container 106. The supply airflow 138 cools the cargo 118 in the cargo compartment of the container 106. It is to be appreciated that the refrigeration system 120 can further be operated in reverse to warm the container 106 when, for example, the outside temperature is very low.
The refrigeration system 120 is positioned in a frame 142 and contained in an accessible housing 144, with the frame 142 and/or the housing 144 secured to an exterior side of the front wall 114 such that the refrigeration system 120 is positioned between the front wall 114 and the tractor 102, as shown in FIG. 1A.
It will be appreciated by those of skill in the art that the systems and configurations of FIGS. 1A and 1B are merely exemplary and provided for illustrative and descriptive purposes only. The disclosure is not limited thereby. For example, although a tractor-trailer configuration is shown, systems may be employed in other trailer configurations, in various truck configurations, and/or in other systems and configurations employing refrigeration units and/or systems, transportation or otherwise.
In some refrigeration systems, a chemical coolant-based refrigeration system may be employed. In a chemical coolant-based refrigeration system, a tank or other container may be configured within the cargo compartment of the trailer, and may be in fluid communication with the refrigeration unit to provide a coolant to the system, i.e., the chemical coolant. For example, in some configurations the chemical coolant may be ammonia, although other chemicals may be used without departing from the scope of the present disclosure. Further, in some configurations, the condenser may be located external to the cargo compartment of the trailer.
Turning now to FIG. 2, a thermochemical refrigerant refrigeration system is shown. In FIG.2, a container transportation system 200 or other cargo transportation system may include a trailer 202 and a container 206. The container 206 may define a cargo space therein and at one end of the container 206 may be a refrigeration system 220. The refrigeration system 220, as shown, includes a condenser 224 and an evaporator 228. The refrigeration system 220 includes other components that are not shown for simplicity. The evaporator 228 may include a tank or be fluidly connected to a tank that contains a thermochemical refrigerant, such as ammonia. As shown, the condenser 224 may be located outside of the container 206, such as mounted thereto, and the evaporator 228 may be located within the container 206, such as mounted to a sidewall of the container 206. The refrigeration system 220, configured as a thermochemical refrigerant refrigeration system may not include a compressor. Rather, the cooling effect is provided by a chemical reaction of the thermochemical refrigerant. The evaporator 228 may provide cooled air 246 into a cargo space defined by the container 206. The refrigeration system 220 may be a closed or sealed refrigeration system that is configured to minimize and/or prevent leaks of the thermochemical refrigerant into the cargo or container space.
At one end of the container 206 may be a door 248 that is configured to open and close. In an open state, the door 248 may enable access from the outside into the cargo space of the container. In the closed state, the door 248 may provide a closed or contained state of the container. In some embodiments, the door 248 may be configured to provide a seal such that fluids, such as liquids and/or gases may not be able to pass through the door 248.
The door 248 and/or the container 206 may include a locking mechanism 250. The locking mechanism 250 may be configured to lock or seal the door 248 in the closed state. Further, the locking mechanism 250, as shown, is located on the interior of the container 206 such that when engaged and locking the door 248, the locking mechanism 250 may not be accessible from the exterior of the container 206.
The container 206 may also include one or more sensors 252. The sensors 252 may be configured to detect the presence of the thermochemical refrigerant that is used in the thermochemical refrigerant based refrigeration system 220. That is, the sensors 252 may be configured to detect a leak of the thermochemical refrigerant within the container 206 and/or any thermochemical refrigerant that is present outside of the refrigeration system 220. As shown, a first sensor is located on the ceiling of the container 206 and a second sensor is located on the floor of the container 206. In some embodiments, the sensors 252 may be configured to detect the presence of the thermochemical refrigerant within the ambient air of the container 206. In some embodiments, only one sensor and/or one general location of sensor may be employed. Some, thermochemical refrigerants are lighter than air and appropriate sensors may only be required to be installed on a ceiling or roof of a container. For example, ammonia may be used as a thermochemical refrigerant, with ammonia being lighter than air, and thus ammonia sensors may only be installed on the top, ceiling, or roof of a container in which an ammonia-based thermochemical refrigerant system is used.
The sensors 252 may be in communication with a safety controller 254 that may be located within the container 206, as shown, although the location of the safety controller 254 is not limited to being located within the container 206. The safety controller 254 may be configured to receive data or signals from the one or more sensors 252. The communication between the safety controller 254 and the one or more sensors 252 may be by wired and/or wireless communication. The safety controller 254 may also be in operable communication with the locking mechanism 250 and the refrigeration system 220.
The safety controller 254 may be configured to operably controller the locking mechanism 250 and at least a portion of the refrigeration system 220. For example, the safety controller 254 may be configured operably control a valve and/or a power supply of the refrigeration system 220. The safety controller 254 may be configured to determine if a leak of the thermochemical refrigerant is leaking within the container 206. For example, a threshold value, which may be zero or greater, may be set such that when the safety controller 254 receives data or information from the sensors 252 that a presence of the thermochemical refrigerant within the container 206 is above the threshold, the safety controller may control the locking mechanism 250 to lock and seal the door 248 and/or may turn off the refrigeration system 220 and/or shut a thermochemical refrigerant flow within the refrigeration system 220 by operation of a valve.
As such, in the event of a leak of the thermochemical refrigerant from the refrigeration system 220, a safety mechanism and operation is provided to prevent users to access the cargo space of the container 206 such that the user may be kept from harmful contact with the thermochemical refrigerant. In some embodiments, the safety controller 254 may be optionally configured to send a signal or notification to a user or other system to indicate that a leak is present and/or may be configured to provide an alarm such as a light or sound indicating there is a leak.
The safety controller 254 and/or the locking mechanism 250 may be configured to maintain the locked and sealed state of the door 248 until the concentration of the thermochemical refrigerant within the container 206 drops below the threshold and/or until a proper treatment and/or maintenance operation is performed.
As shown, the container 206 includes two sensors 252. However, any number of sensors may be used and the position may be varied and is not limited to only the top and/or bottom of the container 206. For example, in one non-limiting embodiment, only one sensor may be used and may be positioned in a location to readily detect a leak of the thermochemical refrigerant. In other embodiments, multiple sensors may be used at various locations. Further, in some embodiments, the sensor location may be based, in part, on the type of thermochemical refrigerant to be detected. For example, if the thermochemical refrigerant, in a leak, is lighter than the air within the container, the sensor may be located above the evaporator, the thermochemical refrigerant tank, and/or a portion of the refrigeration system. However, if the thermochemical refrigerant, in a leak, is heavier than the air within the container, it may be appropriate to locate the sensor below the evaporator, the thermochemical refrigerant tank, and/or a portion of the refrigeration system.
Although shown with an independent or separate controller 254 in FIG. 2, those of skill in the art will appreciate that other control configurations are possible. For example, a locking controller may be integrally configured with the locking mechanism 250, with the locking controller in communication with the one or more sensors 252, and when a thermochemical refrigerant level is detected above the threshold, the locking controller controls the locking mechanism 250 to lock the door 248. Similarly, a refrigeration controller integral with the refrigeration system 220 may be configured in communication with the one or more sensors 252 and upon a leak or other event where the sensors detect the thermochemical refrigerant above the threshold, the refrigeration controller may control the refrigeration system to shut down or otherwise prevent further leakage of the thermochemical refrigerant.
Further, in some embodiments, the sensors may be integrally located and positioned within or on a portion of the refrigeration system. For example, one or more sensors may be located at predetermined locations that may be subject to leaks, such as along coolant fluid lines.
In some embodiments, the sensors 252 and/or the safety controller 254 may be provided with dedicated power, such as batteries or other power sources. In some embodiments, the power may be supplied from a vehicle or other engine or motor and/or from grid power, depending on the configuration.
Turning now to FIG. 3, a flow process in accordance with a non-limiting embodiment of the present disclosure is shown. The flow process 300 may be performed within and as part of a refrigeration system that is configured to cool a space using thermochemical refrigerants. For example, the flow process 300 may be performed with systems described herein and/or other refrigeration systems.
At block 302, one or more sensors located within a cargo space may be configured to detect the presence of a thermochemical refrigerant in the air. For example, the sensors may be configured to detect the presence of a thermochemical refrigerant that is used in a refrigeration system that is configured to cool the cargo space. The sensors may monitor for the presence of the thermochemical refrigerant in the air and/or may be configured to detect a particular concentration and/or threshold amount of the thermochemical refrigerant in the air. As such, a threshold may be any concentration, including zero. The sensors may be in communication with a controller or other device.
At block 304, the sensors may detect the presence of the thermochemical refrigerant at a level above a predefined threshold. For example, the threshold may be the mere presence of the thermochemical refrigerant in the air or may be a specific concentration, such as a value in parts per million or parts per billion, or some other measurement. When the sensors detect the presence of the thermochemical refrigerant above the predefined threshold, the sensors are configured to send a signal or other information to the controller, either wirelessly or by wired connection.
At block 306, the controller is configured to operate a locking mechanism on a door of the container to secure the door closed and prevent someone from opening the door. The locking mechanism may be a magnetic or electromagnetic lock, may be a mechanical lock, or other type of locking mechanism.
Further, at block 308, the controller may be configured to operate a portion of the refrigeration system to stop the refrigeration system. For example, the controller may be configured to electrically turn off the refrigeration system, may be configured to control a valve to prevent further flow of the thermochemical refrigerant coolant within the refrigeration system, or may be configured to provide other control of the refrigeration system to stop the system, and thus prevent further leakage of the thermochemical refrigerant into the cargo space of the container.
At block 310, the controller may be optionally configured to provide a notification of thermochemical refrigerant levels above the predefined threshold. In some embodiments, the notification may be a message sent to a monitoring system or a user, such as an email or text. In some embodiments, the notification may be an alert such as a sound or light that is located on the container to indicate that a leak of the thermochemical refrigerant has occurred and notifies persons of the potential for hazardous conditions.
Advantageously, embodiments described herein provide a safety system for containers that is configured to automatically detect the presence of a thermochemical refrigerant within a container space and automatically lock doors and/or shut down a refrigeration system of the container.
For example, as noted above, although two sensors are provided in the example, those of skill in the art will appreciate that any number of sensors may be used without departing from the scope of the present disclosure. Further, although described and show with respect to containers that are located and part of a trucks, those of skill in the art will appreciate that containers include the present systems may include transportation containers, shipping containers, sea containers, or storage rooms or other confined or enclosed spaces that have refrigeration systems.
Accordingly, the present disclosure is not to be seen as limited by the foregoing description, but is only limited by the scope of the appended claims.

Claims

A safety system comprising:
a container (206) comprising a door (248) wherein the container defines a cargo space;

a refrigeration system (220), wherein at least a portion of the refrigeration system is located at one end of the container and having at least one thermochemical refrigerant;

at least one sensor (252) located within the container and configured to detect a presence of the at least one thermochemical refrigerant within an ambient air in the container;

a locking mechanism (250) operably configured to automatically lock and seal the door of the container such that persons cannot enter; and

a safety controller in communication with the at least one sensor and operably connected to the refrigeration system and the locking mechanism, the safety controller configured to lock and seal the container with the locking mechanism when the at least one sensor detects the presence of the at least one thermochemical refrigerant within the ambient air in the container above a predetermined threshold.
The safety system of claim 1, wherein the safety controller (254) is configured to shut off the refrigeration system when the at least one sensor detects the presence of the at least one thermochemical refrigerant within the ambient air in the container above a predetermined threshold.
The safety system of claim 1 or 2, wherein the at least one thermochemical refrigerant is ammonia.
The safety system of any of the preceding claims, wherein the at least one sensor (252) comprises a sensor located on a ceiling of the container (206) and a sensor located on a floor of the container.
The safety system of any of the preceding claims, wherein the refrigeration system (220) includes a tank configured to contain the thermochemical refrigerant, the tank located within the container (206).
The safety system of any of the preceding claims, wherein the container (206) is a container of a tractor trailer system.
The safety system of any of the preceding claims, wherein the safety controller (254) is configured to control at least one of a valve or a power supply to the refrigeration system (220) such that when the safety controller shuts off the refrigeration system it prevents fluid flow of the thermochemical refrigerant within the refrigeration system.
The safety system of any of the preceding claims, further comprising a notification system configured to provide a notification that the at least one thermochemical refrigerant is present within the container (206) above the threshold.
A method of providing safety for a container (206) having a refrigeration system according to claim 1, wherein the container defines a cargo space, the method comprising:
monitoring with at least one sensor (252) located within the container for a presence of the at least one thermochemical refrigerant within an ambient air in the container;

detecting the presence of the at least one thermochemical refrigerant within the ambient air in the container above a predefined threshold; and

controlling a locking mechanism (250) to lock and seal a door (248) of the container when the presence of the at least one thermochemical refrigerant within the ambient air in the container above a predetermined threshold is detected.
The method of claim 9, further comprising controlling the refrigeration system to shut off the refrigeration system when the presence of the at least one thermochemical refrigerant within the ambient air in the container above a predetermined threshold is detected.
The method of claim 9 or 10, wherein the at least one thermochemical refrigerant is ammonia.
The method of any of claims 9-11, wherein both the locking mechanism (250) and the refrigeration unit are controlled when the presence of the at least one thermochemical refrigerant within the ambient air in the container (206) is detected above the predetermined threshold.
The method of any of claims 9-12, wherein the refrigeration system (220) includes a tank configured to contain the thermochemical refrigerant, the tank located within the container (206).
The method of any of claims 9-13, further comprising providing a notification that the at least one thermochemical refrigerant is present within the container (206) above the threshold.
The method of any of claims 9-14, wherein controlling the refrigeration system (220) comprising controlling at least one of a valve or a power supply to the refrigeration system such that when the refrigeration system shuts off it prevents fluid flow of the thermochemical refrigerant within the refrigeration system.