Patent Publication Number: US-2015088321-A1

Title: Self-Learning Closed-Loop Control Valve System

Description:
STATEMENTS REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not Applicable. 
     NAMES OF THE PARTIES TO A JOINT RESEARCH AGREEMENT 
     Not Applicable. 
     REFERENCE TO A “SEQUENCE LISTING”, A TABLE, OR A COMPUTER PROGRAM 
     Not Applicable. 
     BACKGROUND 
     Technical field: Valve systems are used in heating, ventilation, and air-cooling (HVAC) pipe systems, including in regard to pressure independent control valves used to regulate and maintain the fluid flow rate and/or energy use/transfer of said pipe systems. 
     Conventional pressure-independent control or energy valves rely on the use of magnetic flow meters or sensors for measuring flow and ball valves for controlling flow. Such systems often have low accuracy levels because magnetism-based sensors can fail to function properly due to debris, metal, or wayward ferrous materials in the pipe system while the ball valves require special characterization to accurately control flow. Further, such systems may rely on the use of ball valves to modulate the flow of fluid which are expensive to manufacture and thus increases the overall costs of these valve systems. In addition, at certain pipe diameters, ball valves as implemented into prior systems may become prohibitively expensive to produce for a piping system. 
     Thus, a need exists for a lower cost, and higher-accuracy alternative to the traditional pressure independent control valve systems. 
     BRIEF SUMMARY OF THE EMBODIMENTS 
     An adaptive and/or self-learning, predictive, and based upon known C, characteristics, closed loop control butterfly valve system, apparatus, and method for the purpose of regulating or maintaining a predetermined flow rate and/or energy usage/transfer, including a pipe system defining a flow path for a volume of fluid to regulate flow downstream of the pressure independent control valve system, wherein the pipe system has a butterfly valve configured to control a flow rate of the volume of fluid; an ultrasonic sensor configured to transmit and receive a signal across the flow path; and an electronic transducer processor in data communication with the ultrasonic sensor and the butterfly valve. 
     As used herein, “C v ” is defined as the volume of water in U.S.G.P.M. (U.S. gallons per minute) that will flow through a given restriction or valve opening with a pressure drop of one (1) p.s.i. (pound per square inch) at room temperature. “C v  characteristic” may be expressed as and is inclusive of values, coefficients, and plotted curves or curves. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
       The embodiments may be better understood, and numerous objects, features, and advantages made apparent to those skilled in the art by referencing the accompanying drawings. These drawings are used to illustrate only typical embodiments of this invention, and are not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments. The figures are not necessarily to scale and certain features and certain views of the figures may be shown exaggerated in scale or in schematic in the interest of clarity and conciseness. 
         FIG. 1  depicts a schematic side, elevation view of one embodiment of a self-correcting closed loop control valve system. 
         FIG. 2  depicts a cross sectional view of one embodiment of an ultrasonic flow sensor arrangement for use in a self-correcting closed loop control valve system. 
         FIG. 3  depicts a cross sectional view of an alternative embodiment of an ultrasonic flow sensor arrangement for use in a self-correcting closed loop control valve system. 
         FIG. 4  depicts a schematic view of a butterfly valve for use in a self-correcting closed loop control valve system. 
         FIG. 5  depicts a block diagram of an embodiment of data storage, input, collection and processing for output in the self-correcting closed loop control valve system. 
     
    
    
     DETAILED DESCRIPTION OF EMBODIMENT(S) 
     The description that follows includes exemplary apparatus, methods, techniques, and instruction sequences that embody techniques of the inventive subject matter. However, it is understood that the described embodiments may be practiced without these specific details. 
       FIG. 1  depicts a schematic side view of one embodiment of a self-correcting closed loop control valve system  100  in which a flow path  130  runs therethrough as part of a pipe system  101 . On the upstream end  105  of the valve system  100  and as part of the pipe system  101  is spool or measurement-conduit  102 , which defines a flow chamber  114  through which flow path  130  travels into. On the downstream end of valve system  100  is valve assembly  120 , through which flow path  130  exits into the remainder of the pipe system  101 . The fluid which travels along flow path  130  may be any type of fluid. For example, the fluid may be any fluid typically used within an HVAC system, including, but not limited to: water, or a water/glycol mixture; or the fluid may be any other type of fluid travelling through a pipe system  101 . 
     Valve assembly  120  and spool  102  may be coupled together through flange connections  122 . Valve assembly  120  includes a valve  128  (which flow path  130  travels therethrough) and an actuator  112 . Valve  128  is preferably a butterfly valve  129  (see  FIG. 4 ) although the valve  128  may be any type of valve able to control and gradually modify the flow of a fluid, including, but not limited to ball valves, or any type of valve as best determined by one of ordinary skill in the art. The selection of the valve  128  may be dependent on a desired C, characteristic, or flow coefficient or flow characteristic, curve of the type of valve. By way of example only, a butterfly valve  129  may have a C, curve that is more linear than a ball valve, and as a result may be more desirable to rapidly and easily control the flow rate. In certain exemplary preferred embodiments it is critical or desirable to implement the valve  128  as a butterfly valve  129  to achieve a more linear relationship between the valve opening position and its corresponding C, characteristic. Valve  128  or butterfly valve  129  may be actuated by any type of automated actuator  112  best determined by one of ordinary skill in the art, including, but not limited to: a pneumatic, or electric powered actuator. 
     With reference to  FIG. 4 , the valve  128  is represented as a butterfly valve  129 . The butterfly valve  129  has a stem  124 , a disc  125 , and a diameter  131  defined by the opening through the butterfly valve  129 . The stem  124 , disc  125 , diameter  131  and the disc  125  angular position relative to the opening/diameter  131  are all factors in determining a C, characteristic of the butterfly valve  129 . In certain exemplary and preferred embodiments it is critical that the valve  128  is a butterfly valve  129 . Such a butterfly valve  129  may be a resilient seated butterfly valve commercially available from Bray International, Inc. of Houston, Tex., USA. 
     In the embodiment depicted within  FIGS. 1-2 , two sensors  110   a  and  110   b  are positioned diametrically at an angle across the flow chamber  114  of spool  102 , in such a way that transmitted and received signals are directed towards the other respective sensor  110   a  or  110   b.  Sensors  110   a  and  110   b  are retained in sensor supports  106 , which are mounted to the external surface of spool  102 . Further, sensors  110   a  and  110   b  are preferably flush with or slightly recessed into the interior surface  103  of spool  102  so as to not introduce additional disturbance, turbulence or variance into the flow path  130 . Sensors  110   a  and  110   b  are ultrasonic sensors (comprising an ultrasonic flow meter) capable of both transmitting and receiving signals  126  in the form of ultrasonic waves or vibrations across the flow of fluid in flow chamber  114 . The angle at which sensors  110   a  and  110   b  are positioned, may be increased or decreased to modify the distance or length traveled by the signal  126  through the fluid medium (the angle can vary depending upon the application e.g.: pipe diameter). Spool  102  may also include temperature sensor(s)  134  to collect and record the fluid temperature and temperature change of flow chamber  114  and/or pipe system  101  and to communicate to an electronic transducer processor  104  (although the temperature sensor(s) may be mounted elsewhere in or connected to the pipe system  101 ). 
     To calculate the flow of fluid in the pipe system, the sensor  110   a  transmits an ultrasonic signal  126  at an angle across the flow path  130  to sensor  110   b,  which receives the signal  126 . The period of time taken by signal  126  to reach a sensor  110   a  or  110   b  is affected by the velocity of the fluid in flow path  130 . Sensor  110   b  records the time at which the signal  126  is received, and may also transmit a signal  126  back to sensor  110   a.  Sensor  110   a  also records the time at which any second signal  126  is received, and may transmit another signal  126  to sensor  110   b.  The back-and-forth transmittal and receipt process between the sensors  110   a  and  110   b  is continuously, periodically, or intermittently conducted, as desired, while the flow of the pipe system is to be monitored and maintained at a predetermined or preferred flow rate as entered into electronic transducer processor  104 . The data regarding the recorded times of transmission and receipt of the signals  126 , and the temperature and temperature change of the valve system  100  are used to calculate the flow rate of the fluid in the flow chamber  114 . 
     Wires  108  may carry the data from sensors  110   a,    110   b,  and  134  to electronic transducer processor  104  where the data are collected, recorded, compared, and calculated. Although wires  108  are illustrated within the included drawings, wires  108  are not necessary for communication of the data; wireless communication of the data from the sensors  110   a,    110   b,  and  134  to electronic transducer processor  104  is also envisioned to be a part of the disclosed embodiments. 
     The electronic transducer processor  104  is generally implemented as electronic circuitry and processor-based computational components controlled by computer instructions stored in physical data-storage components, including various types of electronic memory and/or mass-storage devices. It should be noted, at the onset, that computer instructions stored in physical data-storage devices and executed within processors comprise the control components of a wide variety of modern devices, machines, and systems, and are as tangible, physical, and real as any other component of a device, machine, or system. Occasionally, statements are encountered that suggest that computer-instruction-implemented control logic is “merely software” or something abstract and less tangible than physical machine components. Those familiar with modern science and technology understand that this is not the case. Computer instructions executed by processors must be physical entities stored in physical devices. Otherwise, the processors would not be able to access and execute the instructions. The term “software” can be applied to a symbolic representation of a program or routine, such as a printout or displayed list of programming-language statements, but such symbolic representations of computer programs are not executed by processors. Instead, processors fetch and execute computer instructions stored in physical states within physical data-storage devices. Similarly, computer-readable media are physical data-storage media, such as disks, memories, and mass-storage devices that store data in a tangible, physical form that can be subsequently retrieved from the physical data-storage media. 
     When electronic transducer processor  104  determines that the flow rate in flow chamber  114  requires adjustment in order to maintain or modify to the desired flow rate or energy usage/transfer, the electronic transducer processor  104  communicates the necessary correction to an electronic controller  136  connected to the actuator  112  of the valve assembly  120  to change the position of valve  128 . The electronic controller  136  manipulates the actuator  112  to the desired amount of actuation for the necessary movement of the valve  128  in order to regulate flow rate or volume. Alternatively, the electronic transducer processor  104  can directly communicate to and manipulate the actuator  112  if it is an electronic type actuator (in other words the electronic transducer processor  104  and controller  136  may be combined into a unitary controller as further described below). The control/determination steps may also occur within the electronic transducer processor  104  and/or controller  136 , or in combination between the two, despite that the algorithm and associated computational steps are generally discussed as occurring within electronic transducer processor  104  within this disclosure. Upon receipt of instructions from electronic transducer processor  104 , the position of valve  128  is adjusted accordingly by actuator  112  such that the flow rate, flow volume or energy use/transfer is maintained at the predetermined, or set rate. 
     On an ongoing basis for self-correction of valve system  100 , the electronic transducer processor  104  processes the learned and sensed information according to one or more advanced control algorithms or calculations, and then automatically adjusts the actuator  112  to a set-point flow rate or energy usage level, and/or to optimize energy usage. The amount of adjustment required can be predicted or inferred by knowing in advance and stored within the memory of the electronic transducer processor  104  or electronic controller  136  the C v  curve/characteristic of the controlling butterfly valve  129 . The electronic transducer processor  104  accesses and uses a variety of different types of stored information, data, and inputs, including optionally user/operator input, in order to generate output control commands that control the operational behavior of the electronic controller  136 . Such information or data, whether received to the electronic transducer processor  104  by user-input or sensor feedback, includes at least: flow rate feedback from sensors  110   a  and  110   b,  temperature feedback from sensor(s)  134 , and valve positioning in order to control/determine whether the actuator  112  should change or adjust the valve position so as to maintain a desired or constant flow rate downstream of the valve  120  whilst accounting for, e.g., input pressure changes. Historical data may be a further input into the control/determination in order to improve the efficiency of the self-correcting, “smart” system as implemented input into the algorithm to enhance and optimize dynamic, “real-time”, control of (or ability to maintain a constant) flow rate or energy use/transfer. Additional information used by the electronic transducer processor  104  in its algorithms may include one or more stored control schedules, immediate control inputs received through a control or display interface, and data, commands, and other information received from remote data-processing systems, including cloud-based data-processing systems. In addition to generating control output to manipulate the electronic controller  136 , the electronic transducer processor  104  may also provide a graphic or display interface that allows users/operators to easily input data for a desired flow-rate or energy usage level, to create and modify control schedules and may also output data and information to remote entities, other “smart” electronic transducer processors, and to users through an information-output interface. 
     Operation of the electronic controller  136  will alter the pipe system  101  environment within which sensors  110   a,    110   b,  and  134  are embedded. The sensors return sensor output, or feedback, to the electronic transducer processor  104  through wires  108  or wireless communication. Based on this feedback, the electronic transducer processor  104  modifies the output control commands in order to achieve the specified flow rate or energy usage for the self-correcting closed loop valve system  100 . In essence, the electronic transducer processor  104  modifies the output control commands according to two different feedback loops. The first, most direct feedback loop includes feedback from sensors  110   a,    110   b,  and  134  that the electronic transducer processor  104  can use to determine subsequent output control commands or control-output modification in order to achieve the desired flow rate or energy use for the valve system  100 . The second feedback loop involves environmental, historical information, or other feedback to users which, in turn, may elicit subsequent user control and inputs to the electronic transducer processor  104 . In other words, users can either be viewed as another type of sensor that outputs immediate-control directives and control-schedule changes, rather than raw sensor output, or can be viewed as a component of a higher-level feedback loop. 
     The electronic transducer processor  104  itself may be mounted onto the external surface of spool  102  as depicted in  FIG. 1 , or may be located elsewhere within the valve system  100 . For example, but not limited to the following: the electronic transducer processor  104  may be physically coupled to the electronic controller  136  or, optionally, the electronic transducer processor  104 , electronic controller  136  and/or actuator  112  may be integrated into one physical electronic unit. Moreover, while  FIG. 1  depicts an electronic controller  136  mounted on top of actuator  112 , electronic controller  136  may be elsewhere located within valve system  100 , and may also be combined physically with the actuator  112 . 
       FIG. 5  depicts a schematic view of the valve system  100  including the electronic transducer processor  104  (or the integrated electronic transducer processor  104 , electronic controller  136  and/or actuator  112 ) according to an embodiment. The valve system  100  may have a storage device  140 , a data input  142 , a data collection unit  144 , an assessment analysis unit  146 , a historical data unit  148 , a comparative analysis unit  150 , and an output  152 . The storage device  140  may be any suitable storage device for storing data. 
     In a working example of the adaptive and/or self-learning, predictive functionality of the valve system  100 , the electronic transducer processor  104  is in communication with or integrated with the controller  136 , and the data input unit  142  may be used to input, for example, but not limited to, the C v  characteristic of the butterfly valve  129 . The data collection unit  144  and the historical data unit  148  may be used to input or collect and record, for example but not limited to, data of the flow rate, the temperature, and the valve position of the butterfly valve  129 . The comparative analysis unit  150  may be used to compare any or all of the data input  142  with the data collection unit  144  and the historical data unit  148  (for example, to compare historical data with the C v  characteristic of the butterfly valve  129 ) in order to determine the output  152  in response to the comparative analysis unit  150  and in communication with the controller  136 . The optional assessment analysis unit  146  may receive the categorized data from the data collection unit  144  in order to tabulate and/or determine if there is any present or future risk and/or maintenance item likely in the valve system  100 . The risk and/or maintenance may be based on real time events that are taking place in the operations and/or based on predictive events that are likely to occur. The assessment analysis unit  104  may classify the risks and/or maintenance for valve system  100 . 
     An alternate arrangement or embodiment of sensors  110   a  and  110   b  is depicted in  FIG. 3 , which may be a more favorable organization of sensors  110   a  and  110   b  for smaller diameter pipeline systems. In  FIG. 3 , the sensor  110   a  is mounted at angle to transmit a signal  126  against the interior surface  103  of the spool  102 . The interior surface  103  of spool  102  then reflects the signal  126  to sensor  110   b,  which records the time at which the signal  126  is received and transmits another signal  126  to bounce off of the interior surface of spool  102  to sensor  110   a.  Sensor  110   a  repeats the same to sensor  110   b.  The process is repeated continuously, periodically, or intermittently for so long as a regulated flow rate/volume or energy use/transfer of the pipe system is desired. In this embodiment, a reflector  132  may be optionally mounted on the interior surface  103  of spool  102  to assist in the reflection or “bouncing” of the signal  126  to the sensors  110   a  and  110   b.    
     While the embodiments are described with reference to various implementations and exploitations, it will be understood that these embodiments are illustrative and that the scope of the inventive subject matter is not limited to them. Many variations, modifications, additions and improvements are possible. For example, the techniques used herein may be applied to any valve system or assembly used for piping systems. 
     Plural instances may be provided for components, operations or structures described herein as a single instance. In general, structures and functionality presented as separate components in the exemplary configurations may be implemented as a combined structure or component. Similarly, structures and functionality presented as a single component may be implemented as separate components. These and other variations, modifications, additions, and improvements may fall within the scope of the inventive subject matter.