Patent Publication Number: US-11391307-B2

Title: Hydraulic tank protection system

Description:
The present disclosure relates generally to a hydraulic tank protection system and, for example, to a hydraulic tank protection system for preventing diesel exhaust fluid from entering a hydraulic system. 
     BACKGROUND 
     A hydraulic machine, such as, for example, a backhoe loader, a cold planer, a wheel loader, a compactor, a paver, a forest machine, a forwarder, a harvester, an excavator, an industrial loader, a tractor, a dozer, or another type of mining, construction, farming, robotic, and/or transportation equipment, may include a hydraulic system for using liquid fluid power to perform work. The hydraulic system may include a motor, a pump, a generator, a hydraulic tank or reservoir, a hydraulic cylinder, and/or the like. To utilize liquid fluid power to perform work, the hydraulic system may cause hydraulic fluid contained in the hydraulic tank to be pumped to the hydraulic cylinder. 
     Diesel exhaust fluid (DEF) is an aqueous urea solution that is commonly used to lower nitrogen oxide (NOx) concentration in diesel exhaust emissions from a diesel engine of a machine such as a hydraulic machine. DEF is stored in a tank on board a vehicle and injected into an exhaust stream by a metering system. 
     Commonly, an inlet or fill tube of the tank storing the DEF is positioned near an inlet or fill tube of a hydraulic tank of a hydraulic system. The proximity of the fill tube of the tank storing the DEF to the fill tube of the hydraulic tank may cause DEF fluid to be inadvertently added to the hydraulic tank and subsequently distributed throughout the hydraulic system. Although non-toxic, DEF can corrode some metals. Because DEF can corrode some metals, the addition of the DEF fluid to the hydraulic tank and/or the subsequent distribution of the DEF throughout the hydraulic system may cause the hydraulic system to be damaged. The damage caused to the hydraulic system may result in the repair and/or replacement of one or more components of, or the entire, hydraulic system. 
     One attempt to determine a type of fluid being utilized in a machine is disclosed in U.S. Pat. No. 7,647,844 B2 that issued to Toshiaki Kawanishi et al. on Jan. 19, 2010 (“the &#39;844 patent”). In particular, the &#39;844 patent discloses a flow rate/liquid type detecting method for detecting the flow rate of a fluid and, at the same time, detecting any one of or both the type of the fluid and the concentration of the fluid. 
     While the flow rate/liquid type detecting method of the &#39;844 patent may detect a type of a fluid being utilized within a system, the &#39;844 patent does not suggest that the flow rate/liquid type detecting method can prevent a fluid that may harm or damage the system from entering the system. Further, the &#39;844 patent does not suggest a system that can prevent a fluid that may harm or damage a hydraulic system from entering the hydraulic system. 
     The hydraulic tank protection system of the present disclosure solves one or more of the problems set forth above and/or other problems in the art. 
     SUMMARY 
     According to some implementations, a method may include receiving, via a fill tube of a hydraulic tank, a fluid; determining, by a sensor, a characteristic of the fluid; determining, based on the characteristic of the fluid, whether the fluid comprises a first type of fluid; and selectively actuating a fluid control device to control a flow of the fluid into or out of a reservoir of the hydraulic tank based on whether the fluid comprises the first type of fluid. 
     According to some implementations, a machine may include a hydraulic tank and a protection system. The hydraulic tank may include a fill tube and a reservoir. The protection system may include a sensor to detect a characteristic of the fluid, a fluid control device to control a flow of the fluid into or out of the reservoir, and an electronic control module to receive, from the sensor, information indicating the characteristic of the fluid, determine, based on the characteristic of the fluid, whether the fluid comprises a first type of fluid, and selectively provide a control signal to actuate the fluid control device to control the flow of the fluid into or out of the reservoir based on whether the fluid comprises the first type of fluid. 
     According to some implementations, a system may include a hydraulic tank and a protection system. The hydraulic tank may include a reservoir and a fill tube. The fill tube may allow a fluid to flow into the reservoir. The protection system may include at least one of a first fluid control device to control a flow of the fluid into the reservoir or a second fluid control device to control a flow of the fluid out of the reservoir, a sensor to determine a characteristic of the fluid, and an electronic control module to receive a signal from the sensor, the signal indicating the characteristic of the fluid, determine, based on the characteristic of the fluid, that the fluid comprises a first type of fluid, and selectively provide, based on whether the fluid comprises the first type of fluid, a control signal to actuate the at least one of the first fluid control device or the second fluid control device. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is diagram of an example machine having a hydraulic system. 
         FIG. 2  is a diagram of an example hydraulic tank protection system. 
         FIG. 3  is a diagram of an example hydraulic tank that includes a hydraulic tank protection system. 
         FIG. 4  is a diagram of an example hydraulic tank that includes a hydraulic tank protection system. 
         FIG. 5  is a diagram of an example hydraulic tank that includes a hydraulic tank protection system. 
         FIG. 6  is a flow chart of an example process for controlling a flow of a fluid into and/or out of a reservoir of a hydraulic tank. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  is a diagram of an example a machine  100 . In the example of  FIG. 1 , the machine  100  is a cold planer that includes a hydraulic system  102 . The machine  100  is used to remove material, such as hardened asphalt, from a ground surface, such as a roadway. A conveyor system  104  may transfer the material from the ground surface to a haul vehicle  106  (e.g., a wagon or tractor trailer). 
     As shown in  FIG. 1 , the machine  100  has a frame  108  supported by one or more traction devices  110 , a milling drum  112  rotationally supported under a belly of the frame  108 , and an engine (not shown) mounted to the frame  108  and configured to drive traction devices  110  and milling drum  112 . The traction devices  110  may include either wheels or tracks that are connected to actuators  114  of the hydraulic system  102  to controllably raise and lower frame  108  relative to a ground surface. The same or different actuators  114  may be used to steer the machine  100  and/or to adjust a travel speed of the traction devices  110 . The conveyor system  104  is connected at a leading end to the frame  108  and is configured to transport material away from the milling drum  112  and into a receptacle, such as the haul vehicle  106 . The frame  108  also supports an operator station  118 . The operator station  118  houses a control console  120  with any number of interface devices  122  used to control the machine  100  and/or the hydraulic system  102 . 
     As indicated above,  FIG. 1  is provided as an example. Other examples may differ from what is described in connection with  FIG. 1 . 
       FIG. 2  is a diagram of an example hydraulic tank protection system  200 . The hydraulic tank protection system  200  may be configured to prevent an unwanted fluid, such as diesel exhaust fluid (DEF), from entering and/or exiting one or more portions of a hydraulic tank  300  (e.g., a reservoir  302  and/or a fill tube  304 ) (shown in  FIGS. 3-5 ). As shown in  FIG. 2 , the hydraulic tank protection system  200  includes a sensor  202 , a fluid control device  204 , an electronic control module (ECM)  206 , and/or an alert system  208 . 
     The sensor  202  is a sensor device configured to detect a characteristic of a fluid and transmit information identifying the detected characteristic to the ECM  206 . For example, the sensor  202  may be a pH sensor, an urea sensor, a liquid density sensor, and/or the like. The sensor  202  may be configured to detect a pH balance and/or an urea content of a fluid and may transmit a signal that indicates, and/or information identifying, the pH balance and/or urea content of the fluid to the ECM  206 . 
     The fluid control device  204  is a device configured to control a flow of fluid. The fluid control device  204  may be a gate, a valve, and/or the like that can be actuated between an open state or position to permit a flow of the fluid and a closed state or position to prevent a flow of the fluid. For example, the fluid control device  204  may be actuated to control a flow of a fluid into and/or out of one or more portions of the hydraulic tank  300 , such as the reservoir  302 , the fill tube  304 , and/or the conduit  306 . 
     Alternatively, and/or additionally, the fluid control device  204  is a device configured to stop the operation of a machine associated with the hydraulic system  102  to control a flow of a fluid into and/or out of one or more portions of the hydraulic tank  300 , such as the reservoir  302 , the fill tube  304 , and/or the conduit  306 . For example, the fluid control device  204  may be a device configured to stop the operation of the machine  100  and/or the hydraulic system  102  to prevent a fluid from flowing out of the reservoir  302  and/or into the conduit  306 . 
     The ECM  206  includes one or more processors and may execute software that permits the ECM  206  to provide signals to, or interpret signals from, one or more components of the hydraulic tank protection system  200 . The one or more processors are implemented in hardware, firmware, or a combination of hardware and software and take the form of a central processing unit (CPU), a graphics processing unit (GPU), an accelerated processing unit (APU), a microprocessor, a microcontroller, a digital signal processor (DSP), a field-programmable gate array (FPGA), an application-specific integrated circuit (ASIC), or another type of processing component. 
     The software permits the ECM  206  to receive a signal from the sensor  202 , determine a type of a fluid based on the signal received from the sensor  202 , provide a signal to the fluid control device  204  to actuate the fluid control device  204  between the open and closed positions, and/or provide a signal to the alert system  208  to cause the alert system  208  to perform an action as described below. 
     The alert system  208  is a system configured to receive a signal from the ECM  206  and to perform an action based on the received signal. The action may be any action intended to notify a user that a fluid has been determined to be a particular type of fluid and/or that a fluid has been determined not to be a particular type of fluid. For example, the action may include causing a set of one or more light emitting diodes (LEDs) to be illuminated, causing an audible message to be emitted via a speaker, preventing operation of the hydraulic system, preventing an operation of a vehicle associated with the hydraulic system, causing a notification to be transmitted to a user device, and/or the like. 
     As indicated above,  FIG. 2  is provided as an example. Other examples may differ from what is described in connection with  FIG. 2 . For example, while the hydraulic tank protection system  200  is described as including a single sensor  202  and a single fluid control device  204 , the hydraulic tank protection system  200  may include a plurality of sensors  202  and/or a plurality of fluid control devices  204 . 
       FIG. 3  is a diagram of an example hydraulic tank  300  that includes a hydraulic tank protection system  200 . As shown in  FIG. 3 , the hydraulic tank  300  includes the reservoir  302 , the fill tube  304 , the conduit  306 , the sensor  202 , the fluid control device  204 , the ECM  206 , and the alert system  208 . 
     The reservoir  302  is a container that holds hydraulic fluid, such as a petroleum-based hydraulic fluid, utilized by the hydraulic system  102 . For example, a hydraulic fluid may be input into the hydraulic system via the fill tube  304 . The fill tube  304  is a structure that allows the hydraulic fluid to flow into the reservoir  302 . A pump (not shown) of the hydraulic system  102  causes the hydraulic fluid to be provided from the reservoir  302  to one or more actuators  114  of the hydraulic system  102  (and/or from the one or more actuators  114  and into the reservoir  302 ) via a conduit  306 . 
     The hydraulic tank protection system  200  may control a flow of a fluid exiting the fill tube  304  and/or entering the reservoir  302 . For example, a user may pour a fluid into the fill tube  304 . As shown in  FIG. 3 , the sensor  202  may be located or positioned within the fill tube  304 . As the fluid is being poured into the fill tube  304 , the sensor  202  detects a characteristic of the fluid. In some implementations, the sensor  202  is a pH sensor and detects a pH level of the fluid. Alternatively, or additionally, the sensor  202  is an urea sensor and detects an urea content of the fluid and/or another property of the fluid. 
     Based on detecting the characteristic of the fluid, the sensor  202  transmits a signal to the ECM  206 . The signal includes information identifying the detected characteristic of the fluid. The ECM  206  receives the signal and determines the characteristic of the fluid based on the included information. The ECM  206  determines a type of the fluid based on the characteristic of the fluid. 
     In some implementations, the ECM  206  determines a property of the fluid based on the characteristic. The ECM  206  determines a type of the fluid based on the property of the fluid. 
     For example, the signal may include information identifying the pH level of the fluid. The ECM  206  determines a type of the fluid based on determining whether the pH level of the fluid satisfies a threshold pH level. 
     Alternatively, or additionally, the signal may include information identifying an urea content of the fluid. The ECM  206  determines a type of the fluid based on the urea content of the fluid. 
     The ECM  206  determines a state or position of the fluid control device  204 . For example, the ECM  206  determines whether the fluid control device  204  is in the open state or position or the closed state or position. Based on the fluid being DEF, and when the fluid control device  204  is in the open state or position, the ECM  206  transmits a signal to the fluid control device  204  to cause the fluid control device  204  to transition from the open state or position to the closed state or position to prevent the DEF from entering the reservoir  302 . 
     When the fluid control device  204  is in the closed state or position, the ECM  206  transmits a signal to the fluid control device  204  to prevent the fluid control device  204  from transitioning from the closed state or position to the open state or position. Alternatively, when the fluid control device  204  is in the closed state or position, the ECM  206  may determine not to transmit a signal to the fluid control device  204 . 
     As shown in  FIG. 3 , the fluid control device  204  may be positioned at or near an end of the fill tube  304  to control a flow of the fluid into the reservoir  302 . The fluid control device  204  receives the signal transmitted by the ECM  206  and actuates (or refrains from actuating) into the open or closed state or position based on the signal. 
     As indicated above,  FIG. 3  is provided as an example. Other examples may differ from what is described in connection with  FIG. 3 . 
       FIG. 4  is a diagram of an example hydraulic tank  300  that includes a hydraulic tank protection system  200 . As shown in  FIG. 4 , the hydraulic tank protection system  200  may be located or positioned within the reservoir  302  to control a flow of a fluid exiting the reservoir  302  and/or entering the conduit  306 . For example, a user may pour a fluid into the fill tube  304 . The fluid may flow through the fill tube  304  and into the reservoir  302 . 
     As the fluid enters the reservoir  302 , and/or while the fluid is within the reservoir  302 , the sensor  202  detects a characteristic of the fluid. To detect a characteristic of the fluid as the fluid enters the reservoir  302 , the sensor  202  may be positioned in the reservoir  302  near or adjacent to an end of the fill tube  304 . Because DEF is a denser fluid relative to hydraulic fluid, DEF may settle to be within a bottom portion of the reservoir  302 . As shown in  FIG. 4 , to detect DEF within the reservoir  302 , the sensor  202  may be positioned near (e.g., on and/or adjacent to) a bottom surface of the reservoir  302 . 
     The sensor  202  may transmit a signal including information identifying the characteristic of the fluid to the ECM  206 , in a manner similar to that as described above with respect to  FIG. 3 . The ECM  206  receives the signal and determines a type of the fluid in a manner similar to that described above with respect to  FIG. 3 . 
     The ECM  206  determines a state or position of the fluid control device  204 . For example, the ECM  206  determines whether the fluid control device  204  is in the open state or position or the closed state or position. When the fluid is a type of fluid that is unwanted or harmful (e.g., DEF), and when the fluid control device  204  is in the open state or position, the ECM  206  transmits a signal to the fluid control device  204  to cause the fluid control device  204  to transition from the open state or position to the closed state or position to prevent the DEF from exiting the reservoir  302  and/or entering the conduit  306 . 
     When the fluid is a type of fluid that is unwanted or harmful (e.g., DEF), and when the fluid control device  204  is in the closed state or position, the ECM  206  transmits a signal to the fluid control device  204  to prevent the fluid control device  204  from transitioning from the closed state or position to the open state or position. Alternatively, when the fluid control device  204  is in the closed state or position, the ECM  206  may determine not to transmit a signal to the fluid control device  204 . 
     As shown in  FIG. 4 , the fluid control device  204  is positioned at or near an end of the conduit  306  to control a flow of the fluid exiting the reservoir  302  and/or entering the conduit  306 . The fluid control device  204  may actuate to, or remain in, the open or closed state/position to control a flow of the fluid out of the reservoir  302  and/or into the conduit  306  based on the signal received from the ECM  206 . 
     As indicated above,  FIG. 4  is provided as an example. Other examples may differ from what is described in connection with  FIG. 4 . 
       FIG. 5  is a diagram of an example hydraulic tank  300  that includes a hydraulic tank protection system  200 . In some implementations, the hydraulic tank protection system  200  controls a flow of a fluid exiting the fill tube  304  (e.g., entering the reservoir  302 ) and controls a flow of a fluid exiting the reservoir  302  (e.g., entering the conduit  306 ). For example, as shown in  FIG. 5 , the hydraulic tank protection system  200  includes a sensor  202 - 1  and a fluid control device  204 - 1  positioned to control a flow of a fluid exiting the fill tube  304  and/or entering the reservoir  302  in a manner similar to that described above regarding  FIG. 3 . Additionally, the hydraulic tank protection system  200  includes a sensor  202 - 2  and a fluid control device  204 - 2  positioned to control a flow of a fluid exiting the reservoir  302  and/or entering the conduit  306  in a manner similar to that described above regarding  FIG. 4 . 
     In operation, the fluid control device  204 - 1  may be in an open state or position and a rate at which a type of fluid that is unwanted or harmful (e.g., DEF) flows through the fill tube  304  may be sufficient to allow a portion of the unwanted or harmful fluid to enter the reservoir  302  prior to the fluid control device  204 - 1  actuating into the closed state or position. The sensor  202 - 2  detects a characteristic of the portion of the unwanted or harmful fluid that entered into the reservoir  302  and transmits a signal to the ECM  206  that includes information identifying the characteristic of the portion of the unwanted or harmful fluid. 
     The ECM  206  determines a type (e.g., DEF) of the portion of the unwanted or harmful fluid based on the information identifying the characteristic of the portion of the unwanted or harmful fluid. The ECM  206  determines whether the fluid control device  204 - 2  is in the open state or position or the closed state or position. Based on the fluid being identified as a type of fluid that is unwanted or harmful, and when the fluid control device  204 - 2  is in the open state or position, the ECM  206  transmits a signal to the fluid control device  204 - 2  to cause the fluid control device  204 - 2  to transition from the open state or position to the closed state or position to prevent the portion of the unwanted or harmful fluid from exiting the reservoir  302  and/or entering the conduit  306 . 
     When the fluid control device  204 - 2  is in the closed state or position, the ECM  206  transmits a signal to the fluid control device  204 - 2  to prevent the fluid control device  204 - 2  from transitioning from the closed state or position to the open state or position. Alternatively, when the fluid control device  204 - 2  is in the closed state or position, the ECM  206  may determine not to transmit a signal to the fluid control device  204 - 2 . 
     As shown in  FIG. 5 , the fluid control device  204 - 2  is positioned at or near an end of the conduit  306  to control a flow of the fluid exiting the reservoir  302  and/or entering the conduit  306 . The fluid control device  204 - 2  receives the signal transmitted by the ECM  206  and actuates (or refrains from actuating) into the open or closed state or position to prevent the portion of the unwanted or harmful fluid from exiting the reservoir  302  and/or entering the conduit  306 . 
     As indicated above,  FIG. 5  is provided as an example. Other examples may differ from what is described in connection with  FIG. 5 . 
       FIG. 6  is a flow chart of an example process  600  for controlling a flow of a fluid into and/or out of a reservoir  302  of a hydraulic tank  300 . In some implementations, one or more process blocks of  FIG. 6  may be performed by a hydraulic tank protection system (e.g., hydraulic tank protection system  200 ). 
     As shown in  FIG. 6 , process  600  may include receiving, via a fill tube of a hydraulic tank, a fluid (block  602 ). For example, to add a fluid to a hydraulic system, fluid may be poured into a reservoir  302  of a hydraulic tank  300  via a fill tube  304  of the hydraulic tank  300 , as described above. 
     As further shown in  FIG. 6 , process  600  may include determining a characteristic of the fluid (block  604 ). For example, a sensor  202  of the hydraulic tank protection system  200  may be a pH sensor, an urea sensor, and/or another type of sensor and may determine a characteristic of the fluid, such as a pH level, an urea content, and/or another property of the fluid, as described above. 
     As further shown in  FIG. 6 , process  600  may include determining, based on the characteristic of the fluid, whether the fluid comprises a first type of fluid (block  606 ). For example, the characteristic of the fluid may be a pH level and/or an urea content of the fluid and the ECM  206  may determine, based on the pH level and/or the urea content of the fluid, whether the fluid comprises a first type of fluid, such as DEF, as described above. 
     As further shown in  FIG. 6 , process  600  may include selectively actuating a fluid control device to control a flow of the fluid into or out of a reservoir of the hydraulic tank based on whether the fluid comprises the first type of fluid (block  608 ). For example, the ECM  206  may selectively actuate a fluid control device  204  to control a flow of the fluid into or out of the reservoir  302  of the hydraulic tank  300  based on whether the fluid comprises the first type of fluid, as described above. 
     Selectively actuating the fluid control device  204  may include closing, when the fluid comprises the first type of fluid, the fluid control device to prevent the fluid from entering the reservoir; opening, when the fluid comprises the first type of fluid, the fluid control device to permit the fluid to exit the reservoir; refraining from opening, when the fluid does not comprise the first type of fluid, the fluid control device to allow the fluid to enter the reservoir; or refraining from closing, when the fluid does not comprise the first type of fluid, the fluid control device to prevent the fluid from exiting the reservoir. 
     The hydraulic tank  300  may be operatively coupled to a machine  100  and when the fluid is determined to be the first type of fluid, an operation of the machine  100  may be prevented and/or an alert to a user of the machine  100  may be output, for example, by the alert system  208 . 
     Process  600  may include additional implementations, such as any single implementation or any combination of implementations described above and/or in connection with one or more other processes described elsewhere herein. 
     Although  FIG. 6  shows example blocks of process  600 , in some implementations, process  600  may include additional blocks, fewer blocks, different blocks, or differently arranged blocks than those depicted in  FIG. 6 . Additionally, or alternatively, two or more of the blocks of process  600  may be performed in parallel. 
     INDUSTRIAL APPLICABILITY 
     The disclosed hydraulic tank protection system  200  may be used with any hydraulic system  102  where prevention of a particular type of fluid, such as DEF, from entering the hydraulic system  102  is desired. The disclosed hydraulic tank protection system  200  may determine a type of fluid entering and/or within a reservoir  302  of a hydraulic tank  300  and may actuate a fluid control device  204 , such as a valve, a gate, and/or a device configured to stop an operation of a machine  100  associated with the hydraulic tank protection system  200 , to control of a flow of the fluid into and/or out of the reservoir  302  based on the type of the fluid. 
     In this way, the hydraulic tank protection system  200  protects the hydraulic system  102  from damage and/or the inefficient or impaired operation of the hydraulic system  102  caused by the introduction of a harmful fluid, such as DEF, into the hydraulic system  102 . By protecting the hydraulic system  102  from damage and/or the inefficient or impaired operation of the hydraulic system  102 , the hydraulic tank protection system  200  protects a machine  100  utilizing the hydraulic system  102  (e.g., a cold planer) from damage and/or inefficient or impaired operation caused by the introduction of a harmful fluid, such as DEF, into the hydraulic system  102 . Such damage and/or impairment may occur due to the harmful fluid negatively impacting parts of the hydraulic system  102  and/or the machine  100 , causing mechanical failures (e.g., due to causing corrosion to of one or more metal parts of the hydraulic system  102 ) and/or the like. Accordingly, including the hydraulic tank protection system  200  with a hydraulic system  102  may lower costs of replacing equipment, maintenance, and/or repairs relative to previous hydraulic systems by preventing harmful fluids from entering and/or exiting the reservoir  302  of the hydraulic tank  300 .