Flow controls are important in many industries. Whether found on process lines, gas distribution networks, or any system that carries flowing material, flow devices like valve assemblies are vital to regulate material flow within set parameters. Or, in case of problems, the valve assembly can shut-off flow altogether.
Valve assemblies often leverage mechanical mechanisms to regulate flow. These mechanisms may include an actuator that couples with a closure member via a stem. The closure member may embody a plug, a ball, a butterfly valve, and/or like implement that can contact a seat to prevent flow. A sensing mechanism may be useful to monitor the position of the closure member relative to a seat. This sensing mechanism can have a position sensor and a mechanical linkage that couples the position sensor with the stem or other structure that moves in concert with the closure member. In some examples, the actuator includes a pneumatic actuator that converts energy (e.g., compressed air) into mechanical motion to cause the closure member to move between an opened position, a partially opened position, and a closed position.
Valve assemblies may also include computing components that automate operation of the device. These components may integrate as part of a “controller” or “valve positioner.” During operation, the valve positioner receives and processes a control signal from a process control system (also “distributed control system” or “DCS system”). The control signal may define operating parameters for the valve assembly. These operating parameters may set an appropriate flow of material through the valve assembly and into the process line. The valve positioner can translate the operating parameters, often in combination with the output from the position sensor, to regulate instrument gas into the actuator. The instrument gas may pressurize (or de-pressurize) the actuator in a way that moves the valve stem and, in turn, locates the closure member in position relative to the seat to coincide with the operating parameters.
The subject matter disclosed herein relates to improvements that provide seamless data exchange between a valve assembly and a remote device. Of particular interest are embodiments that leverage wireless data transmission technology, like near-field communication or NFC, to allow an end user (e.g., technician) to interact with the device using a smartphone or tablet (or, generally, a remote or handheld computing device). This concept makes use of computing power available on the remote computing device, which is typically better suited to support a user interface or other rich, interactive environment, as compared to the valve positioner on the valve assembly. The embodiments may also do away with any wired data connection between the valve positioner and the handheld computing device. This feature can alleviate safety concerns, as well as to ensure integrity of the valve positioner, because the technician no longer needs to remove any parts (e.g., covers) that would normally facilitate data access by way of physical electronics or connectors on the valve positioner.
Reference is now made briefly to the accompanying drawings, in which:
Where applicable, like reference characters designate identical or corresponding components and units throughout the several views, which are not to scale unless otherwise indicated. The embodiments disclosed herein may include elements that appear in one or more of the several views or in combinations of the several views. Moreover, methods are exemplary only and may be modified by, for example, reordering, adding, removing, and/or altering the individual stages.
The discussion that follows describes improvements to enhance flow control hardware to wirelessly exchange data. The improvements are discussed in context of a valve assembly, but the subject matter may apply to other devices, including many of those in the flow control space (e.g., pressure regulators, actuators, etc.). Valve assemblies may benefit because these devices often have power limitations that frustrate design changes to incorporate relevant new technology. In this regard, the embodiments here leverage components that work within these power limitations to expand functions for wireless connectivity. Some configurations of these components may, in fact, generate or harvest energy to provide power in situ so as to avoid or reduce power draw on the power loop of the valve assembly. This feature may permit valve assemblies to not only wirelessly transfer new classes of data, such as for diagnostics, but also wirelessly connect into a larger system of inter-networked devices and components. Other embodiments are within the scope of this disclosure.
At a high level, the data exchange device 100 facilitates simple and efficient data exchange between the devices 102, 104. Its hardware, namely the exchange components 120, 122, can be configured so that the field 124 conforms with near-field communication (NFC) protocols that provide short-range wireless connectivity. In accordance with these NFC protocols, the exchange components 120, 122 may operate as a “target” and an “initiator,” respectively. The initiator 122 launches the communication protocol and controls the data exchange and the target 120 responds to the requests from the initiator 122.
Use of NFC-configured hardware on the valve assembly 106 overcomes limitations that often foreclose use of energy “hungry” devices, like WIFI and mobile antennas, to enable wireless communication. For example, the first exchange component 118 draws very little power to operate as the “target.” This characteristic is ideal for use within power limitations on flow controls and similar devices. These limitations may cap available power at less than 40 mW because the valve assembly 106 often finds itself as part of a larger control network, or distributed control system (DCS), that operates the device (and, generally, a process line) using protocols (e.g., 4-20 mA, FOUNDATION Fieldbuss, PROFIBUS, etc.) in this low power range. Location and design of the valve assembly and the process lines can also limit access to supplemental power like a battery (or similar “on-board” supply) or facility power (or other “off-board” power options).
The NFC-configured hardware may foreclose the need for such supplemental power anyway. Interestingly, bringing the exchange components 120, 122 in proximity to one another may allow the exchange component 120 to harvest energy from the exchange component 122. This energy may be enough to power the exchange component 120 on the valve assembly 106 so that very little to no extra power is necessary to operate this component. This feature not only addresses power limitations, but also certain drawbacks that prevail with any potential supplemental power supply. For example, battery cells are often not a viable option due to safety requirements in hazardous areas (e.g., arcing and sparking concerns). Duty cycle of the exchange component 120 (e.g., short duration, high power) may also tend to drain battery cells rather quickly. And, rechargeable battery cells might not be viable either because the prevailing power available (e.g., less than 40 mW) would not likely provide sufficient power to maintain charge of the battery cell.
The NFC-configured hardware also addresses limitations with the resident integrated interface 108 available on the valve assembly 106. Practice to date has been to leverage the on-board devices 110, 112 as the primary modality for the technician to interact with the valve assembly 106. Here, however, the technician may leverage features of the user interface 118 in lieu of the on-board devices 110, 114. These features may be available via software (and like executable instructions) on the computing device 114, which itself may have expanded memory and processing to offer a rich, robust user experience via the user interface 118. This environment may provide access to functions (e.g., diagnostics) not previously available via the on-board devices 108, 110. Moreover, this user experience may offer more robust features and tools that are far superior to the typical “pushbutton” configuration of the keyboard 112 that often frustrates technicians because it is limited in functionality and particularly cumbersome and time-consuming to use in the field. Shifting operation to the computing device 114 is also beneficial because the on-board display 108 may have a dearth of usable visible space, ineffective brightness (e.g., there is often no backlighting that can frustrate reading), and insufficient operational capabilities (e.g., the on-board display 108 is often operational only to −20° C., but the valve assembly 106 may find use in conditions with temperatures as low as −40° C.).
Further, the NFC-configured hardware can simplify certain operation and maintenance tasks on the valve assembly 108. For example, practices to date have technicians carry out local firmware updates with “hard-wired” connections that extend from the valve assembly 106 to, e.g., a laptop computer. This approach requires the technician to remove covers to properly access connection points in the valve assembly 106 for connectors (e.g., banana plugs or the like). The proposed “wireless” connection via NFC-configured hardware forecloses the need for this hard-wired approach, which itself can save time and money, not only by speeding up the update process but also avoiding common pitfalls like restrictions that prevent access to the covers due to safety concerns or process interruption.
Use of the NFC devices 126, 128 may facilitate data exchange in the normal course of operation at a plant or industrial site. These operations may have a technician approach the valve assembly 106 (on a process line) to interrogate it for maintenance or other diagnostics. The technician can bring his smartphone 114 (or other “handheld” computing device) within close proximity to the valve assembly 106, measured here generally as a threshold distance D, to stimulate data exchange via the field 124. The threshold distance D may be defined in accordance with the construction of NFC devices 126, 128 and NFC protocol standards. Inductive coupling between the coils 130 can occur at distances from 0 to about 20 cm. But in practice the best distance for inductive coupling may occur from 0 to about 5 cm, so the threshold distance D may be within a range of about 0 to 5 cm for reliable communication between the target 120 and initiator 122. NFC standards provide proper RF signal format and modulation, as well as proper coding schemes for the data to be transferred on the RF signal (e.g., Manchester coding format, 10% modulation, and amplitude shift keying as the format for the NFC modulation). Depending upon the chosen coding scheme, data transfer rates may be one of 106, 212 or 424 kbps, but this is does not limit transfer in scope as other technology may be developed to increase transfer in appropriate formats.
Induction coil 130 may be configured to facilitate data exchange between the devices 126, 128 via the field 124. Care should also be taken to locate the coil 130 in position relative to the enclosure 148 so as to promote communication between the devices 126, 128. Any position should permit field 124 to readily pass through side walls of the enclosure 148. The winding may occupy as much surface area as possible within confines allowable by structure adjacent the devices 126, 128. That is, it may benefit use of the disclosed and contemplated concepts to make the coil 130 as large as possible, with as many turns as possible, given any physical limitations for the NFC device 126 on the valve assembly 106 and, to the extent possible, for the NFC device 128 on the computing device 114. In one implementation, a majority of the winding should be close to the enclosure 148, for example, not more than 10 millimeters from a side wall. It may be useful to encapsulate or conformally coat the coil 130 so as to meet safety and operational requirements.
Industry standards at the time of this writing limit the size of memory available on the tag device 132. The limitations are often 2 kilobytes (kB). The data stored on the tag device 132 can include various executable instructions or “code” that configure the tag device 132 to interact with the NFC reader 134 on the computing device 114. These instructions may configure the tag device 132 to respond to an initialization protocol when the tag device 132 is energized. The instruction may also configure the tag device 132 to complete a handshake-type protocol or sequence establishing a communication link with the NFC reader 134. This communication link may permit full transfer of user-defined data related to the flow control 102. The data stored on the tag device 132 typically is read-only in normal use, but in some implementations may be rewritable as well.
The NFC reader 134 may be configured to read from or write to the tag device 132. These configurations may embody an integrated circuit that can modulate the 13.56 MHz RF signal (e.g., field 126) that carries the data messages to the tag device 132. In practice, the NFC reader 134 may store executable instructions (e.g., computer programs, firmware, application software, etc.) that are specific to the valve assembly 106, such as graphical displays for data history, calibration, configuration, and diagnostic functions.
Busses 152, 154 may embody standard or proprietary communication protocols. Examples of the protocols include UART, SPI, I2C, UNI/O, 1-Wire, or one or more like serial computer busses known at the time of the present writing or developed hereinafter. In operation, the tag device 132 can be passive, meaning it is not energized by the power supply 162. Rather, the tag device 132 (and memory 160, if present) can remain powered off until energized by voltage generated in the coil 130 on the NFC device 126. In other implementations, such as when the main controller 156 is powered on, the tag device 132 may communicate directly with the main controller via the first bus 140, and the memory 160 may not be needed. Use of the separate, second buss 154, however, may serve to couple the tag device 132 with memory 160. In this way, when the NFC device 126 is energized, data and information can transmit via the second bus 154 between the tag device 134 and memory 160, even when the main controller 156 is in a ‘sleep’ mode or otherwise not energized or without power.
As noted herein, the integrated interface 108 can allow the technician to understand and manipulate operations on the valve assembly 106. The display 110 may be an LCD alphanumeric display useful to convey information about operation of the valve assembly 106. This information may include position, pressure, and like values related to operating parameters at the device. The keyboard 112 may embody pushbuttons and like actuatable mechanisms; however, it is possible that the display 110 may include icons that operate in lieu of or to supplement the pushbuttons. The technician can use the pushbuttons, for example, to toggle through valve operating modes or menu structure to manually perform functions to calibrate, configure, or monitor the valve assembly 106.
Memory 160 may provide additional memory storage for data on the electronics assembly 138. It may embody non-volatile random-access memory (NVRAM), which is memory that retains its information when power is turned off. NVRAM can be useful because it stores vastly larger data sets than the tag device 132 which, due to industry standards, may be limited to 32 kilobytes (kB). By way of comparison, firmware upgrades for the controller 136 can comprise about 700 kB of data.
Referring back to
At stage 202, the method 200 receives the signal from the coil. This signal can stimulate the electronic tag device 132 so as to make any information stored thereon available to the NFC-enabled device. In practice, as voltage is applied to the coil 130 on NFC device 128, electric current flows through the windings and produces a magnetic field. Bringing the NFC device 128 in proximity to the coil 130 on the NFC device 126 (on the controller 136) and within their near-field distance (typically about 4 cm.) essentially forms an air-core transformer. This structure induces voltage and current through coil 130 on the NFC device 126, which can energize the electronic tag device 132. In one implementation, the signal may cause allow access to memory 160, whether directly by the NFC-enabled device or by the electronic tag device 132. This feature can increase the amount of data available for exchange between the proximate devices.
At stage 204, the method 200 can properly recognize the NFC-enabled device. This stage may require additional stages for implementing appropriate security measures. For example, stages for processing information that identifies the NFC-enabled device, like serial numbers, checksum valves, and like “password” related information may be important to avoid improper access. In turn, the method 200 may includes stages for processes that access data tables with entries with associate identifying formation with previously-cleared NFC-enabled device. This previously-stored data may, in turn, afford security “clearance” to avoid potential breaches or inappropriate access by non-cleared personnel or devices.
At stage 206, the method 200 generates the output for the handshake. Examples of the output may simply involve processes on-board the valve that, in turn, make certain data available to the NFC-enabled device. In one implementation, the tag device can transmit a reply with data to the NFC-enabled device that opens the communication link.
At stage 208, the method 200 can use the communication link to exchange data. Data can be transmitted from the interface device to the tag device, such as updated calibration information, or a firmware upgrade. Data can also be transmitted from the tag device to the reader module, such as diagnostic data, maintenance information, and valve status. As noted with reference to
In light of the foregoing discussion, the improvements herein allow technicians to easily interact with a valve assembly in the field. The embodiments can leverage powerful feature sets of, for example, a smartphone, to extract, view, and read data to the valve assembly. These features sets outstrip the pushbutton interface often found on the valve assembly. As noted above, the improvements may utilize hardware that resides on the valve assembly. This “valve” hardware may be compatible with NFC hardware found on many handheld devices. The “valve” hardware, however, draws little power from the valve assembly. Indeed its requirements may be well within existing power limitations available on flow controls found in process systems that utilize 4-20 mA, FOUNDATION Fieldbuss, PROFIBUS, and like industrial automation protocols. As an added benefit, the “valve” hardware may also harvest electrical energy that it can use to self-power operation, further reducing the energy “footprint” of this device.
This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. An element or function recited in the singular and proceeded with the word “a” or “an” should be understood as not excluding plural said elements or functions, unless such exclusion is explicitly recited. References to “one embodiment” of the claimed invention should not be interpreted as excluding the existence of additional embodiments that also incorporate the recited features. Furthermore, the claims are but some examples that define the patentable scope of the invention. This scope may include and contemplate other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal language of the claims.
Examples appear below that include certain elements or clauses one or more of which may be combined with other elements and clauses describe embodiments contemplated within the scope and spirit of this disclosure.