WO2014085752A1

WO2014085752A1 - Method for battery powered fuel level measurement

Info

Publication number: WO2014085752A1
Application number: PCT/US2013/072471
Authority: WO
Inventors: Mark Daniel Leasure; Russell Lee Sanders; Matthew Jay Srnec; Mark Alan Johnson
Original assignee: Robertshaw Controls Co; Thermo King Corp
Current assignee: Robertshaw Controls Co; Thermo King Corp
Priority date: 2012-11-30
Filing date: 2013-11-29
Publication date: 2014-06-05
Anticipated expiration: 2015-05-30

Abstract

Device, system, and method for wirelessly communicating a fuel level of a fuel tank to a TRS controller. The electronics of the fuel level sensor, which include a temperature sensor for measuring ambient temperature, are completely sealed and protected from the elements. The fuel level sensor can quickly connect and disconnect to a mechanical floater assembly and/or a fuel tank.

Description

METHOD FOR BATTERY POWERED FUEL LEVEL MEASUREMENT

FIELD

The embodiments disclosed herein relate generally to a device and method for measuring a fuel level in a fuel tank of a transport refrigeration system ("TRS").

BACKGROUND

An electrical/mechanical fuel level sensor device can have a mechanical assembly connected to a potentiometer. The mechanical assembly typically has mechanical gears connected to an arm with a floater. The arm and the floater are disposed inside a fuel tank. A simple fuel level display, that is basically a dial with a needle, can be connected to the mechanical gears so that the needle moves based on the position of the floater. The metal gears can be connected to the potentiometer, such that when the metal gears move, the potentiometer's divided resistances change accordingly. The potentiometer is connected to a remote power source. Generally, the remote power source is a generator set ("genset") of a TRS and electricity is delivered through the potentiometer via an electrical wire. Accordingly, the potentiometer is powered only when the TRS is on and/or is set to provide electricity to the potentiometer. Based on the position of the arm of the mechanical assembly, the mechanical gear can move a sliding contact of the potentiometer to affect its electric potential. Accordingly, the movement of the mechanical gears due to the position of the arm displaced by the floater being floated by the fuel in the fuel tank, can change the electric potential at the potentiometer, which can be detected via the same electrical wire. The measurement of electric potential which may be an approximation of a fuel level in the fuel tank can be sent via measurement signal to a TRS controller of the TRS

The electrical/mechanical fuel level sensor device's accuracy is dependent on the mechanical design and properties of one or more of the fuel tank, mechanical gears, the arm, the floater, and the condition of the wire(s) and any wire connectors that connects the potentiometer to the vehicle's components. Accordingly, the electrical/mechanical fuel level sensor device is not accurate. In particular, the electrical/mechanical fuel level sensor device is not accurate when there is movement of the fuel in the fuel tank (e.g. movement of the transport, vibration from the engine, etc.) and/or when the fuel tank is not in a perfectly leveled position horizontally. That is, the fuel level displayed on the remote display would be inaccurate when the transport temperature controlled trailer unit is going up an incline or going down a decline, because the floater position would move up or down based on the incline or decline angle (i.e. position of the fuel in the fuel tank), and not necessarily an amount of the fuel contained in the fuel tank. There are also many other factors and conditions that prevent the electrical/mechanical fuel level sensor device from an accurate measurement of the fuel level in the fuel tank.

SUMMARY

The embodiments described herein are directed to a fuel level measurement system and a fuel level measurement device for a fuel tank of a transport refrigeration system. The

embodiments described herein include a fuel level measurement system without having a wired connection between the fuel level measurement device and a remote controller that receives the fuel level. An embodiment of the wireless fuel level measurement device includes a memory, which stores computer-readable instructions for: calculating a fuel level, adjusting operation of a fuel level sensor based on a plurality of extrinsic data and intrinsic data, wherein the extrinsic data are data about conditions external to the wireless fuel level measurement device, and the intrinsic data is data about conditions about the wireless fuel level measurement device; and storing a raw data of the fuel level. The embodiment includes a processor in communication with the memory, which executes the computer-readable instructions; a wireless network interface in

communication with the processor for communicating the fuel level to a remote controller; a temperature sensor configured to communicate temperature data to the processor; and a battery that powers the processor, the memory, the temperature sensor, and the wireless network interface. The processor receives the plurality of extrinsic data and the intrinsic data and adjusts the operation of fuel level measurement performed by the processor, and the processor that writes to the memory the data of the fuel level. Examples of extrinsic data, but not limited by, are ambient temperature, noise due to motion of the system. Examples of intrinsic data, but not limited by, are battery condition, system fault detected (out of range condition, detected values outside normal range, expected range, acceptable range, etc.). For example, what is acceptable in regards to range of values, information, and/or data can be predetermined, static, preset, dynamically set, by a user and/or the processor executing a set of computer-readable instructions that can determine what is acceptable. For example, what is unacceptable in regards to values, information, and/or data can be those that are outside the acceptable range of values, information, and/or data.

An embodied method for adjusting an operation of a battery powered device includes detecting an ambient temperature with a temperature sensor and communicating the ambient temperature to a processor, detecting a battery condition and communicating the battery condition to the processor, receiving a raw fuel level data from a mechanical fuel gauge potentiometer by the processor, and the processor determining whether the raw fuel level data is within an acceptable range of values, and adjusting operation of the battery powered device by the processor based on the ambient temperature, the battery condition, and the raw fuel level data. In an embodiment of the method, the raw fuel level data includes a rapid change in a fuel level in a fuel tank; and adjusting operation includes increasing a frequency of generating an electronic report about the fuel level.

In one embodiment, a fuel measurement system and a wireless fuel level measurement device for a TRS are provided. An embodiment of the wireless fuel level measurement device includes a memory, which stores computer-readable instructions for: calculating a fuel level, adjusting operation of a fuel level sensor based on an ambient temperature data and a battery condition data, and logging a data of the fuel level. The wireless fuel level measurement device includes a processor in communication with the memory, which executes the computer-readable instructions, and a wireless network interface in communication with the processor for

communicating the fuel level to a remote controller. The embodiment of the fuel level

measurement device includes a battery that powers the processor, the memory, and the wireless network interface. The fuel level measurement device includes a temperature sensor, wherein the processor receives the ambient temperature data from the temperature sensor and battery condition data from the battery and adjusts the operation of fuel level measurement performed by the processor based on the ambient temperature data and the battery data, and the processor writes to the memory the data of the fuel level to the memory. An embodiment of the wireless fuel level measurement device includes a sealed casing that encases the processor, the memory, the temperature sensor, the wireless network interface, and the battery. The sealed casing can include a housing and a potting material, wherein the processor, the memory, the temperature sensor, the wireless network interface, and the battery are disposed in the housing, and the potting material seals the housing to encase the processor, the memory, the temperature sensor, the wireless network interface, and the battery inside the sealed casing.

In an embodiment, the wireless fuel level measurement device includes a potentiometer connected to the processor for communicating raw fuel level data. The potentiometer can be contained in a compartment that is separated from a compartment of the housing containing the processor, the memory, the temperature sensor, wireless network interface, and the battery.

The potentiometer can be connected to a floater assembly, which includes a floater configured to be floated by a fuel in a fuel tank, and an arm connected to the floater, wherein the arm is displaced when the floater is moved, and the raw fuel level data is determined by a position of the floater.

An embodiment of a fuel level measurement system includes a remote controller that displays the fuel level communicated from the wireless network interface of the wireless fuel level measurement device. The remote controller can also send data to the wireless fuel level measurement device.

An embodiment of a method for producing a sealed wireless fuel level measurement device includes providing a housing; placing logic board inside the housing, wherein the logic board includes a memory, a processor, the temperature sensor, and a wireless network interface; and completely sealing the logic board that is inside the housing by covering an opening of the housing with a layer of a potting material.

The logic board may include a battery for powering the logic board inside the housing. Alternatively, the method can include a step of placing the battery that powers the logic board inside the housing, prior to the step of completely sealing the logic board.

The embodiments described herein can avoid a reset of a battery powered device (e.g., the fuel level sensor) when battery aging and cold temperatures deplete the battery capacity to the point where a low voltage condition is detected or assumed.

The embodiments described herein also can monitor ambient temperature and use an algorithm to adjust wireless transmission and reception rates as part of the fuel level sensor operational profile in order to conserve battery life.

The embodiments described herein can further monitor ambient temperature and use an algorithm to adjust sensor operations in order to conserve battery life.

The embodiments described herein can additionally create a log in the fuel level sensor to capture sensor data for later transmission to a TRS controller when the algorithm prevents wireless data transmission at the normal interval based on ambient temperature or a receiver out of range condition.

The embodiments described herein can be used to monitor the fuel level sensor battery and the ambient temperature from an internal or external source, and adjust the operation of the fuel level sensor device accordingly based on the battery condition, either measured or assumed. The adjustments to the operation can avoid a device reset condition and limit battery

consumption in non-ideal conditions. This can limit high current sensor operations and/or limit wireless communications until ideal conditions return. When communications are interrupted, the fuel level sensor can log and store the sensor data until communications are reestablished.

BRIEF DESCRIPTION OF THE DRAWINGS

Referring now to the drawings in which like reference numbers represent corresponding parts throughout.

FIG. 1 A illustrates a side view of an embodiment of a transport temperature controlled trailer unit with a transport refrigeration system.

FIG. IB illustrates a side view of an embodiment of a trailer unit with a fuel level measurement device system and a cutaway side view of a fuel tank.

FIG. 2 illustrates a cutaway side view of an embodiment of a fuel level measurement device.

FIG. 3 illustrates a front perspective view of an embodiment of a fuel level sensor for a fuel tank of a transport refrigeration system.

FIG. 4 illustrates a rear view of an embodiment of a fuel level sensor for a fuel tank of a transport refrigeration system.

FIG. 5 illustrates a block diagram of an embodiment of the logic board.

FIG. 6 illustrates a flowchart of an embodiment of a method for adjusting an operation of a battery powered device.

DETAILED DESCRIPTION

The embodiments described herein are directed to a transport fuel level measurement device and system. References are made to the accompanying drawings that form a part hereof, and in which is shown by way of illustration of the embodiments in which the methods and systems described herein may be practiced. The term "reefer" generally refers to, for example, a temperature controlled trailer, container, or other type of transport unit, etc. The term "transport refrigeration system" refers to a refrigeration system for controlling the refrigeration of an in internal space of the reefer. The term "wireless" refers to a communication system that is configured to transmit data via a wireless connection over a short distance, such as, for example, between different points of a reefer that is in transport. The term "remote controller" refers to an electronic device that is configured to wirelessly communicate with another wireless device to receive data, manage, command, direct and/or regulate the behavior of the wireless device. An example of the remote controller is a TRS control unit. The term "TRS control unit" refers to an electronic device that is configured to manage, command, direct and regulate the behavior of one or more TRS refrigeration components (e.g., an evaporator, a blower, a heat exchanger, etc.), a TRS engine, a TRS main battery, a TRS alternate battery (if included in the transport refrigeration system), a TRS fuel tank, etc.

FIG. 1A illustrates a side view of a temperature controlled transport unit 100 with a TRS 50. The TRS 50 includes a transport refrigeration unit (TRU) 101, a genset (not shown), and a plurality of wireless sensors including a door sensor 113 and a fuel level sensor 114. The TRU 101 is installed on a side wall of the transport unit 100. In some embodiments, the generator set of the TRS 50 can be mounted under the transport unit 100. The TRS 50 is configured to transfer heat between an internal space 30 of the transport unit 100 and the outside environment. In some embodiments, the TRS 50 is a multizone system in which different zones or areas of the internal space 30 are controlled to meet different refrigeration requirements based on the cargo stored in the particular zone. The TRS 50 also includes a wireless communication system 10 and a fuel tank 110. The wireless communication system 10 includes a network coordinator (not shown), an antenna 20, and a plurality of wireless sensors (e.g., the door sensor 113 and the fuel level sensor 114). The wireless communication system 10 is configured to communicate information regarding the TRS 50 to a remote controller, such as a TRS controller (not shown) of the TRS 50. In some embodiments, the TRS controller can be housed in the TRU 101.

FIG. IB illustrates a side view of an embodiment of a transport temperature controlled trailer unit 100 with a fuel level measurement system 102. The transport temperature controlled trailer unit 100 may be for delivering a reefer with a transport refrigeration system. The fuel level measurement system 102 includes a remote controller 104 (e.g. a TRS controller) that is in wireless communication 106 with a wireless fuel level measurement device 108. The wireless fuel level measurement device 108 is connected to a fuel tank 110 of the transport temperature controlled trailer unit 100. FIG. IB illustrates a cutaway side view of the fuel tank 110 to show the configuration of the fuel level measurement device 108 that is connected to the fuel tank 110. The fuel level measurement device 108 has a floater assembly 1 12 disposed inside the fuel tank 110, and a fuel level sensor 114 disposed outside the fuel tank 110.

FIG. 2 shows a cutaway side view of an embodiment of the fuel level measurement device 108 shown in Fig. IB. The fuel level measurement device 108 includes the floater assembly 112 and the fuel level sensor 114.

The floater assembly 112 includes a floater 116 configured to float on fuel housed inside the fuel tank 110 (shown in Fig. IB). The floater 116 is connected to an arm 118, which is connected to mechanical gears 120. The floater 116 and the arm 118 are configured to be disposed inside the fuel tank. The fuel level sensor 114 includes a potentiometer 122 that connects to the mechanical gears 120. For example, the potentiometer 122 can include one or more magnets 124 that match with one or more magnets 126 of the mechanical gears 120. The potentiometer 122 can be a high impedance potentiometer for enhancing battery life (or service life) of the fuel level sensor 114. The high impedance potentiometer 122 (e.g., 30 kΩ) allows a relatively small amount of current through at this region of the circuit of the fuel level sensor 114 as compared to a low impedance potentiometer (e.g., 240 Ω). Thus, the fuel level sensor 114 including the high impedance potentiometer 122 can have a longer battery life than a sensor which uses the low impedance potentiometer.

The fuel level sensor 114 includes a casing 128. The casing 128 has a housing 130 and a layer of potting material 132. The housing 130 can be made from, for example, an epoxy encapsulant which cures at room temperature to a tough, semi-rigid polymer, which has very good resistance to water, acids and bases and organic solvents.

The housing 130 has a first compartment 134 for containing the potentiometer 122, and a second compartment 136 for containing a logic board 138.

The first compartment 134 has a shaped wall portion 140 configured to mate with the floater assembly 112. For example, the first compartment 134 can include interface fitting structure (e.g. crush ribs) configured to fit tightly with the floater assembly 112.The shaped wall portion 140 is between the first compartment 134 and the second compartment 136. The shaped wall portion 140 may have one or more grooves 142 for wire(s) 144 to travel across between the first compartment 134 and the second compartment 136. The one or more grooves 142 can provide positioning of the wire(s) 144 so as to protect the wire(s) 144 from the environment (e.g. rain, snow, mud, dirt, rocks, etc.) when the fuel level sensor 114 is installed to the fuel tank 110. In an embodiment, the wire(s) 144 are integrally connected to the potentiometer 122 and the logic board 138, without any wire "connectors" (which generally have plastic clips and/or thin metal connectors) that can rust or wear out during normal use over time.

The housing's 130 second compartment 136 is configured to receive and contain the logic board 138. The second compartment 136 is separated from the first compartment 134, such that the second compartment 136 can contain the logic board 138 and be sealed completely and separately from the first compartment 134. The sealing of the second compartment 136 can be performed by providing the layer of potting material 132 over the logic board 138. The result provides a completely sealed logic board 138 contained in a sealed compartment 136 of the casing 128 that protects the logic board 138 from the elements.

FIG. 5 illustrates a block diagram of an embodiment of the logic board 138 for the fuel level sensor 114. The logic board 138 can include (or be connected to) one more or more of a processor 200, a memory 201, a network interface 202, a battery 203, and a temperature sensor 204. In another embodiment, the second compartment 136 contains one more or more of the processor 200, the memory 201, the network interface 202, the battery 203, and the temperature sensor 204. The memory 201 stores computer-readable instructions for carrying out the embodiments of the method described herein.

FIG. 6 illustrates a flowchart of an embodiment of a method 300 for adjusting an operation of a battery powered device, such as the fuel level sensor 114. The method 300 measures and reports fuel levels in a fuel tank, for example, of a commercial transportation environment using a battery powered device. The method 300 can improve the accuracy of reporting the fuel level in the fuel tank when using a mechanical float system (e.g. floater assembly 112 shown in FIG. 3) to provide the raw fuel level data to the fuel level sensor 114. The raw fuel level data does not provide accurate fuel level because there are many factors that can affect the real fuel level in a fuel tank, such as, fuel tank configuration, temperature, etc. The method 300 includes using a computer readable instructions executed by a processor of the fuel level sensor 114, wherein the computer readable instructions include an algorithm which uses either internal or external ambient temperature measurement made by the fuel level sensor 114 to compensate for temperature variations in the fuel tank capacity due to expansion of liquid contents. Further, the method 300 includes computer readable instructions for detecting and compensating for when the fuel tank is in-motion and the fuel level is constantly changing. Thus, the method 300 can achieve improved accuracy of reporting the fuel level in the fuel tank.

The method 300 can also detect and accurately report rapid liquid level change events by altering the calculation methods applied to the sampled data stored in the memory, and a transmission rate (via wireless network interface) of the calculated data (by the processor) based on a fuel level sensor state, which can be adjusted by the processor based on various inputs and/or data. The method 300 can also have a purposefully set outputs from the wireless fuel level sensor to an out of range value for reporting a fault in the system (e.g. the fuel level sensor).

The method 300 allows a battery powered fuel level reporting system that has the ability to measure and report fuel levels wirelessly that is configurable. Further, the method 300 can preserve battery life by the fuel level sensor periodically measuring and transmitting the fuel level to a remote controller, which can store this data in its memory. The method 300 can filter out the noise created by fuel level fluctuation caused by vehicle motion and other external vibration sources while reporting an accurate fuel level. The method 300 can also allow for a rapid response in reporting rapid change events such as fuel loss and fill. A wireless transmission interval and calculation method used to process the data prior to transmitting can be adjusted based on the state of the fuel level sensor. For example, a temperature measurement can provide additional input to the method 300 to allow adjustment of reported fuel level to accommodate temperature-based volume changes. Examples of the method 300 are described below.

Condition 1 : Favorable ambient temperature and battery condition, vehicle in motion, and normal fuel consumption rate.

Sensor reads output of variable resistor coupled to fuel float assembly.

Sensor voltage is within the expected range.

• System determines if temperature and battery condition are acceptable and finds that they are.

Sensor reading is processed along with earlier logged readings.

• No rapid fill or drain activity is detected.

• System determines if out of range condition has been set and finds it has not.

• Transmission of the processed value to the receiver.

Condition 2: Favorable ambient temperature and battery condition, vehicle is stopped, and fuel theft in progress.

Sensor reads output of variable resistor coupled to fuel float assembly.

Sensor voltage is within the expected range.

Sensor reading is processed along with earlier logged readings.

• Processing determines that fuel loss at greater than the expected rate is occurring. Most current sensor reading is sent for transmit, by passing filter.

System determines if out of range condition has been set and finds it has not.

Transmission of the sensor value to the receiver using fast reporting exception.

Condition 3 : Ambient temperature is extremely cold, sensor has been in operation for over 3 years but the battery is generally in good condition, and vehicle is in motion over a rough road.

Sensor reads output of variable resistor coupled to fuel float assembly.

Sensor voltage is within the expected range.

• System determines if temperature and battery condition are acceptable and finds that they are not.

• Out of range condition set. LED is set to blink.

Sensor reading is processed along with earlier logged readings filtering out tank slosh and jarring road impacts.

• No rapid fill or drain activity is detected.

• System determines if out of range condition has been set and finds it has been set.

Transmission of the processed value to the receiver is delayed, sensor readings are logged for storage in the sensor until conditions improve.

• Out of range value is sent to the receiver once temperature conditions improve.

The fuel level sensor described herein improves upon existing wireless transport fuel sensors in the market by using exception-based level reporting and by accommodating motion and stationary states of operation even when subjected to external sources of vibration, mechanical shock, and/or transitional liquids and harmonic events. This fuel level sensor described herein can provide timely, high accuracy reporting while utilizing computer-readable instructions to conserve battery power. Further, the method and device described herein can improves upon existing float based mechanical assemblies that are highly subject to vibration, liquid transitions and mechanical shock where such conditions can cause erroneous reporting of the fuel level. The fuel level sensor also can use an on-board temperature measurement to adjustment for fuel tank volume prior to reporting the overall fuel level. Further, the method and system described herein improves upon other liquid level sensor technology by logging sensor data for later transmission when the conditions have the receiver out of range or ambient temperatures require battery conservation.

The method 300 includes monitoring a temperature 302 and logging 304 temperature data to a memory (i.e. logger) 201. The method 300 includes detecting fuel gauge (i.e. potentiometer) 122 raw data 308 and logging 310 the raw data (i.e. voltage across the potentiometer) to the memory 201.

The method 300 includes determining 312 whether the raw data is within expected range. If the raw data is within expected range, then the processor 200 receives 314 the raw data; if not, then an out of range condition is set 316.

Alternatively, the method 300 can include the processor 200 receiving the raw data and then converting the raw data to derived data. Derived data includes, for example, fuel level (which can be read from the raw data after a scaling) and/or fuel volume (which can be calculated using the raw data and/or fuel level). Then, the method 300 includes determining 312 whether the derived data (e.g., fuel level and/or fuel volume) is within expected range. If derived data is not within expected range, then an out of range condition is set 316. A looping (or continuously monitoring) health check is performed for the sensor 318, and if the health check fails, an out of range condition is set 320. The processor 200 receives the raw data from the potentiometer, and accesses 317 the memory 201 for data retrieval of battery data and temperature data. Then the processor 200 determines 322 whether the fuel level in the fuel tank has changed greater than a normal rate, and if it has changed greater than the normal rate, then a fast reporting to a TRS controller is triggered 324; and if not, then a normal reporting rate 326 is set by the processor. For example, the determining step 322 can include an algorithm which includes a leaky integrator read from the memory 201. The term normal rate is used herein to mean what is expected based on one or more factors, such as the processor 200 determined expected rate based on one or more data according to computer-readable instructions being executed by the processor 200. As a non-limiting example, the fuel level in the fuel tank can have an expected rate of change which is considered to be "normal" based on the use of the fuel in driving a certain quantity of miles and/or use of the engine and other devices. Thus, the processor 200 can execute the computer-readable instructions and determine what would be the expected or normal rate of fuel level change based on the one or more factors involved in determining the fuel level rate of change, and also determine whether the detected fuel level in the fuel tank is outside the normal rate of change. For example, when a fuel level is determined to be 20% or less, a fast reporting can be triggered so the fuel level determination and reporting (transmitting) is performed at a much faster rate than a normal rate.

The processor 200 checks 328 for any out of range condition, for detecting fuel sensor failure, and if there are no out of range conditions 330, the processor 200 transmits the calculated fuel level and/or other data via the wireless network interface to, for example, the TRS controller. If the processor 200 determines that the out of range condition is set 332, then the error data is sent 334 to the wireless network interface and transmitted to, for example, the TRS controller.

A simple fuel level display 146, that is basically a dial with a needle, can be provided at the potentiometer 122 so that the needle moves based on the position of the floater 116.

The floater 116 is floated by a fuel contained in the fuel tank. The floater 116 is connected to the arm 118 of the floater assembly 112, and the displacement of the floater 116 due to the level of the fuel rotates the arm 118 about a pivot 148 at a gear mechanism 120 of the floater assembly 112. The gear mechanism 120 is connected to the potentiometer 122 of the fuel level sensor 114, by for example, a magnetic connection so that the fuel level sensor 114 can be quickly and easily be connected and disconnected from the floater assembly 112.

FIG. 3 shows an embodiment of a front side of an embodiment of a fuel level sensor 114 of a fuel level measurement device 108. The front side of the fuel level sensor 114 would face away from a fuel tank when the fuel level sensor 114 is connected to the fuel tank. The fuel level sensor 114 has a substantially cylindrical shape in general. The analog display 146 having a needle dial 150 is disposed at (or substantially near) the center of the fuel level sensor 114. A beveled view angle portion 152 is angled from a first surface portion 154 of the housing 130 of the fuel level sensor 114 towards the analog display 146. The beveled view angle portion 152 can enhance the visibility of the analog display 146.

In some embodiments, a light-emitting diode (LED) 156 is provided to be visible on the surface portion 154. The LED 156 can be connected to the processor on the logic board 138 for displaying an information regarding an operation and/or condition of the fuel level sensor 114. The housing 130 can include a recess for the LED 156 for enhancing viewability of the LED 156 when lit. FIG. 4 shows and embodiment of a backside (view from the rear) of an embodiment of a fuel level sensor 114. The backside would face towards the fuel tank when the fuel level sensor 114 is connected to the fuel tank. The embodiment of the fuel level sensor 114 shows a first compartment 134 and a second compartment 136 separated by a wall portion 140, wherein the first compartment 134 is disposed near the center of a substantially cylindrically shaped housing 130, with the second compartment 136 forming a ring-shaped compartment which surrounds the first compartment 134. Accordingly, the logic board contained in the second chamber 136 can be substantially ring-shaped to match the shape of the second compartment 136.

The wall portion 140 is configured to receive a gear mechanism of a floater assembly. For example, the wall portion 140 can include an interface fitting structure 141 (e.g. crush ribs) configured to fit tightly with most conventional types of floater assembly. The first compartment 134 contains a potentiometer 122, which has wire(s) 144 extending from it. The wire(s) 144 navigate through the wall portion 140 via matching groove(s) towards a logic board contained in the second compartment 136. The second compartment 136 is completely sealed with a layer of potting material 132.

In an embodiment, a fuel level sensor 114 can be added to an existing resistive fuel gauge and mechanical fuel float assembly, such that the combination provides the resistive fuel gauge to be embedded into a sealed casing with the fuel level measurement device digital component in order to provide a rugged fuel measurement device.

The embodiments of the fuel level measurement device 108 described herein can provide one or more of the following features: Communication of fuel level in a fuel tank to a remote controller is performed wirelessly (wires can degrade over time); also no external wire connectors are needed (like wires, external connectors that connect various electrical components can wear out, be damages, rust, oxidize, etc.); and electronics of the fuel level sensor are completely sealed and protected from the elements.

Advantages of the above embodiments include, but are not limited to, an improvement in reliability of fuel level sensing technology for reefers due to elimination of exposed wires that are subject to damage during transport of the reefer; improvement in the serviceability of the fuel level sensing technology, because wired fuel sensor systems are time consuming to troubleshoot and can be costly to repair, while embodiments of the wireless fuel level measurement device can provide fast and easy installation and/or replacement of the fuel level measurement device to the fuel tank of the transport; and viewability of an analog display. For wired fuel sensor systems, wherein wires provide power to the electronic fuel level measurement devices and/or the wires are conduits of data from the fuel level measurement device to a TRS controller, the wires have been found to be subject to normal wear and tear which disables the fuel sensor system. When damaged, these systems and the wires can be time consuming to repair when there is a case of failure. A wireless fuel level measurement device and system has no exposed wires that can be damaged by normal wear and tear. Further, the wireless fuel level measurement device can be easily and quickly replaced, if there is a case of failure.

Aspects:

It is noted that any of aspects 1-14 and/or features therein can be combined with any of the aspects 15-18 and/or features therein.

1. A wireless fuel level measurement device, comprising:

a memory, which stores computer-readable instructions for: calculating a fuel level,

adjusting operation of a fuel level sensor based on a plurality of extrinsic data and intrinsic data, wherein the extrinsic data is data about conditions external to the wireless fuel level measurement device, and the intrinsic data is data about conditions about the wireless fuel level measurement device, and

storing a raw fuel level data;

a processor in communication with the memory, which executes the computer-readable instructions;

a wireless network interface in communication with the processor for communicating the fuel level to a remote controller;

a temperature sensor configured to communicate temperature data to the processor; and a battery that powers the processor, the memory, the temperature sensor, and the wireless network interface;

the processor receives one or more of the extrinsic data and the intrinsic data and adjusts the operation of fuel level measurement performed by the processor, and the processor that writes to the memory the data of the fuel level.

2. The wireless fuel level measurement device according to aspect 1, further comprising: a sealed casing that encases the processor, the memory, the wireless network interface, and the battery.

3. The wireless fuel level measurement device according to any of the aspects 1-2, wherein the sealed casing includes: a housing, and a potting material, wherein the processor, the memory, the wireless network interface, and the battery are disposed in the housing, and the potting material seals the housing to encase the processor, the memory, the wireless network interface, and the battery inside the sealed casing.

4. The wireless fuel level measurement device according to any of the aspects 1-3, wherein the housing includes a polymer material.

5. The wireless fuel level measurement device according to aspects 1-4, wherein the extrinsic data includes temperature information.

6. The wireless fuel level measurement device according to any of the aspects 1-5, wherein the extrinsic data includes noise information.

7. The wireless fuel level measurement device according to any of the aspects 1-6, wherein the intrinsic data includes a condition of the battery.

8. The wireless fuel level measurement device according to any of the aspects 1-7, wherein the intrinsic data includes a condition of the processor detecting a system fault.

9. The wireless fuel level measurement device according to any of the aspects 1-8, wherein adjusting the operation of fuel level measurement performed by the processor includes the processor changing a frequency of generating an electronic report for communicating the fuel level to the remote controller.

10. The wireless fuel level measurement device according to any of the aspects 1-9, wherein adjusting the operation of fuel level measurement performed by the processor includes the processor changing a wireless transmission rate and a reception rate with the remote controller in order to conserve the battery.

11. The wireless fuel level measurement device according to any of the aspects 1-10, wherein adjusting the operation of fuel level measurement performed by the processor includes the processor changing the temperature sensor operation in order to conserve the battery.

12. The wireless fuel level measurement device according to any of the aspects 1-11, further comprising a potentiometer connected to the processor for communicating the raw fuel level data.

13. A fuel level measurement system, comprising:

the wireless fuel level measurement device according to aspect 12; and

a floater assembly connected to the potentiometer, the floater assembly including:

the floater configured to be floated by a fuel in a fuel tank; and

an arm connected to the floater, wherein the arm is displaced when the floater is moved, and the raw fuel level data is determined by a position of the floater.

14. The fuel level measurement system according to aspect 13, further comprising: the remote controller that stores the fuel level communicated from the wireless network interface.

15. A method of adjusting an operation of a battery powered device, comprising:

detecting an ambient temperature with a temperature sensor and communicating the ambient temperature to a processor;

detecting a battery condition and communicating the battery condition to the processor; receiving a raw fuel level data from a mechanical fuel gauge potentiometer by the processor, and the processor determining whether the raw fuel level data is within an acceptable range of values; and

adjusting operation of the battery powered device by the processor based on the ambient temperature, the battery condition, and the raw fuel level data.

16. The method according to aspect 15, wherein the raw fuel level data includes a rapid change in a fuel level in a fuel tank; and the adjusting operation includes increasing a frequency of generating an electronic report about the fuel level.

17. The method according to aspect 16, wherein the increasing the frequency of generating the electronic report is performed when the fuel level in the fuel tank has increased at a rate greater than a normal rate. 18. The method according to any of aspects 15-16, wherein the increasing the frequency of generating the electronic report is performed when the fuel level in the fuel tank has decreased at a rate greater than a normal rate.

With regard to the foregoing description, it is to be understood that changes may be made in detail, especially in matters of the construction materials employed and the shape, size and arrangement of the parts without departing from the scope of the present invention. It is intended that the specification and depicted embodiment to be considered exemplary only, with a true scope and spirit of the invention being indicated by the broad meaning of the claims.

Claims

1. A wireless fuel level measurement device, comprising:

a memory, which stores computer-readable instructions for:

calculating a fuel level,

adjusting operation of a fuel level sensor based on a plurality of extrinsic data and intrinsic data, wherein the extrinsic data is data about conditions external to the wireless fuel level measurement device, and the intrinsic data is data about conditions about the wireless fuel level measurement device, and storing a raw fuel level data;

2. The wireless fuel level measurement device according to claim 1, further comprising: a sealed casing that encases the processor, the memory, the wireless network interface, and the battery.

3. The wireless fuel level measurement device according to claim 2, wherein the sealed casing includes:

a housing, and a potting material, wherein the processor, the memory, the wireless network interface, and the battery are disposed in the housing, and the potting material seals the housing to encase the processor, the memory, the wireless network interface, and the battery inside the sealed casing.

4. The wireless fuel level measurement device according to claim 3, wherein the housing includes a polymer material.

5. The wireless fuel level measurement device according to claim 1, wherein the extrinsic data includes temperature information.

6. The wireless fuel level measurement device according to claim 1, wherein the extrinsic data includes noise information.

7. The wireless fuel level measurement device according to claim 1, wherein the intrinsic data includes a condition of the battery.

8. The wireless fuel level measurement device according to claim 1, wherein the intrinsic data includes a condition of the processor detecting a system fault.

9. The wireless fuel level measurement device according to claim 1, wherein adjusting the operation of fuel level measurement performed by the processor includes the processor changing a frequency of generating an electronic report for communicating the fuel level to the remote controller.

10. The wireless fuel level measurement device according to claim 1, wherein adjusting the operation of fuel level measurement performed by the processor includes the processor changing a wireless transmission rate and a reception rate with the remote controller in order to conserve the battery.

11. The wireless fuel level measurement device according to claim 1 , wherein adjusting the operation of fuel level measurement performed by the processor includes the processor changing the temperature sensor operation in order to conserve the battery.

12. The wireless fuel level measurement device according to claim 1 , further comprising a potentiometer connected to the processor for communicating the raw fuel level data.

13. A fuel level measurement system, comprising:

the wireless fuel level measurement device according to claim 12; and

the floater configured to be floated by a fuel in a fuel tank; and

14. The fuel level measurement system according to claim 13, further comprising:

the remote controller that stores the fuel level communicated from the wireless network interface.

15. A method of adjusting an operation of a battery powered device, comprising:

16. The method according to claim 15, wherein the raw fuel level data includes a rapid change in a fuel level in a fuel tank; and the adjusting operation includes increasing a frequency of generating an electronic report about the fuel level.

17. The method according to claim 16, wherein the increasing the frequency of generating the electronic report is performed when the fuel level in the fuel tank has increased at a rate greater than a normal rate.

18. The method according to any of claim 16, wherein the increasing the frequency of generating the electronic report is performed when the fuel level in the fuel tank has decreased at a rate greater than a normal rate.