Abstract: The disclosed embodiments include a capacitance diaphragm gauge that includes a self-heated micro-electro-mechanical-system sensor for measuring pressure. The self-heated micro-electro-mechanical-system has at least one integrated heater component and at least one membrane on the self-heated micro-electro-mechanical-system.

Abstract: The disclosed embodiments include a pressure balance valve that solves one or more problems associated with existing designs. For example, in one embodiment, a pressure balancing valve assembly is disclosed that provides a low cost frictionless assembly that is constructed to not seal the leak path between an inlet port and an outlet port. Instead, this leak path is minimized with small angle tapered plunger and a precision bored annulus to provide a defined area for the pressure drop to occur and to limit the flow from the inlet to the outlet.

Abstract: A magnetic core (106) is adapted for a solenoid valve (100). The magnetic core (106) includes a base (113), a stem (112), and an inner cavity (115). The inner cavity (115) is formed in a portion of the base (113) and in a portion of the stem (112). The inner cavity (115) defines a thin wall (108) of the stem (112). The magnetic core (106) further comprises a non-magnetic pressure retaining sleeve (420). The non-magnetic pressure retaining sleeve (420) is arranged in such a way that either the non-magnetic pressure retaining sleeve surrounds at least a portion of the thin wall of the stem or that at least a portion of the thin wall portion surrounds the non-magnetic pressure retaining sleeve.

Abstract: A method is disclosed for determining leakby in a flow controller (100) comprising a flow sensor (102), a flow control valve (106) and electronics (104). The electronics are coupled to the flow sensor, the flow control valve and configured to adjust the flow control valve in response to the signal of the flow sensor indicating the flow rate of the material such that a set flow rate of material through the flow controller is maintained. The steps of the method comprise determining (302) a zero drift (Qdrift) value for the flow sensor (102). Determining (304) a flow rate (Qflow) through the flow controller (100) when the control valve (106) is in the fully closed position. And determining (306) the leakby through the flow controller (100) where the leakby is equal Qflow-Qdrift.

Abstract: Performance of mass flow controller may be vulnerable to pressure transients in a flow path to which the controller is coupled for the purpose of controlling the fluid flow. A system and method are provided for reducing or eliminate performance degradations, instabilities, and/or inaccuracies of a mass flow controller caused by changes in the pressure environment. In particular, a method and system are provided for compensating for pressure transients in the pressure environment of a flow path and mass flow controller.

Abstract: A monolithic manometer and method of sensing pressure changes may include sensing a change in parasitic capacitive coupling between multiple parasitic capacitive coupled conductive elements in response to a diaphragm disturbing the parasitic capacitive coupling between the conductive elements. A signal representative of the sensed change in parasitic capacitive coupling may be output.

Abstract: The present invention relates to a system, method, and computer program product for determining the flow rate of a fluid. The system, method, and computer program product generate a thermal sensor based mass flow rate for the fluid, where the thermal sensor based mass flow rate is determined at least in part from the thermal sensor signal (36). The system, method, and computer program product generate a pressure sensor based mass flow rate for the fluid, wherein the pressure sensor based mass flow rate is determined at least in part from the pressure sensor signal (51a). The system, method, and computer program product generate at least one calibration factor (?) using the thermal sensor based mass flow rate and the pressure sensor based mass flow rate. The system, method, and computer program product may generate a calibrated pressure sensor based mass flow rate by using the at least one calibration factor (?) to modify the pressure sensor based mass flow rate.

Abstract: A system and method for compensating for thermal drift. A temperature is measured in a meter as a temperature voltage. The temperature voltage is converted to a digital signal. The digital signal is processed to generate an offset voltage in response to the digital signal. The offset voltage is applied as an input to an amplifier. The amplifier receives as a second input a gauge voltage. An output is generated from the meter that corrects the gauge voltage using the offset voltage to compensate for thermal drift.

Abstract: A monolithic manometer and method of sensing pressure changes may include sensing a change in parasitic capacitive coupling between multiple parasitic capacitive coupled conductive elements in response to a diaphragm disturbing the parasitic capacitive coupling between the conductive elements. A signal representative of the sensed change in parasitic capacitive coupling may be output.

Abstract: The disclosed embodiments include an apparatus and a method for controlling fluid flow. In accordance with certain of the disclosed embodiments, a valve is disclosed that comprises a yoke that encases a coil. The yoke has a gap adjacent to a central aperture of the yoke. A core tube is placed in the central aperture. The core tube has a core slidingly disposed within an interior chamber for controlling a fluid flow rate from a flow inlet to a flow outlet. A current is provided to the coil. Magnetic flux, generated by the coil in response to the current, is directed through the gap to cause the core to move proportionally based on the amount of current provided to the coil for changing the fluid flow rate from the flow inlet to the flow outlet.

Abstract: A system and method of characterizing or controlling a flow of a fluid is provided that involves a sensor conduit and a bypass. A plurality of fluids may be utilized in the flow control device based on characteristic information of the device generated during calibration thereof. The characteristic information, in turn is based on a dimensionless parameters, such as adjusted dynamic pressure and adjusted Reynolds number.

Abstract: Systems and methods for liquid flow sensing and control for use with a variety of different types of liquid flow measurement and control systems. The liquid flow sensor system senses a flow signal indicative of the flow rate of the liquid flowing in a sensor conduit and analyzes the flow signal to determine, by detecting characteristic changes in the signal, whether a bubble is present in the sensor conduit. Where the system determines that a bubble is present, it may generate an alarm signal indicative of the presence of the bubble. A flow control system incorporating the flow sensor as a feedback source may respond to the detection of a bubble by temporarily freezing the flow control parameters until the bubble has exited the sensor conduit. The flow control system can implement procedures for clearing a bubble from the sensor conduit where the system detects that the bubble has become stuck.

Abstract: According to an illustrative embodiment, a system for calculating an average phase difference in a Coriolis flow meter includes a conduit for transferring a fluid. The conduit is caused to vibrate when the fluid flows through the conduit. The system also includes a first and a second detector operable to detect vibrations at first and second portions of the conduit, respectively. The first and second detectors measure the phase of the first and second vibrations, respectively. The system may also include a timer operable to measure a phase difference between the phases of the first and second vibrations, and a memory operable to store one or more values associated with a plurality of phase differences. The plurality of phase differences may include the phase difference measured by the timer. The system may also include a processor operable to calculate an average phase difference using the one or more values.

Abstract: A system and method of compensating for pressure variations in a flow controller entails the use of the compressibility of the gas being controlled to provide a more accurate measurement of the flow.

Abstract: An improved flow measuring device, such as a mass flow meter or mass flow controller, providing a high turn-down ratio as compared to prior art devices. In accordance with various embodiments of the invention, a flow sensor includes a sensor flow path that includes one or more restrictions configured to provide the sensor flow path with a non-linear relationship between a pressure drop across the sensor flow path and the flow of fluid through the flow sensor conduit. Such a flow sensor preferably achieves a high turn-down ratio by way of a variable bypass ratio that is directly proportional to the sensor tube mass flow rate so that the turn-down ratio of the mass flow controller will be ideally proportional to the square of the turndown achievable by the flow sensor conduit fluid sensing portion alone. In some embodiments, the restriction can be employed as a part of a fluid seal having an orifice and disposed between a flow sensor portion of a flow meter and a bypass portion of the flow meter.

Abstract: A thermal mass flow controller or mass flow meter having a novel sensor housing that reduces heat conduction from the housing mounting plate or base to the sensor itself. The housing also greatly minimizes the thermal gradient that can result from the uneven application of heat to the housing base. This reduction is accomplished in part by the use of one or more thermal isolation slots to isolate the upper portion of the housing (which holds the sensor) from the lower portion of the housing. Heat transfer to the sensor housing is also minimized by raising the middle portion of the bottom of the housing so that thermal contact is made between the base and the housing only at the two ends of the housing.

Abstract: A method of obtaining at least one representation of a characteristic function of a sensor from a test fluid during calibration of the sensor according to a sensor model having a transfer function operating on flow rate, at least one sensor property and at least one fluid property and employing the at least one representation of the characteristic function to determine flow rates through the sensor during operation with an arbitrary fluid.

Abstract: Systems and methods for digitally controlling sensors. In one embodiment, a digital controller for a capacitance diaphragm gauge is embedded in a digital signal processor (DSP). The controller receives digitized input from a sensor AFE via a variable gain module, a zero offset module and an analog-to-digital converter. The controller automatically calibrates the received input by adjusting the variable gain and zero offset modules. The controller also monitors and adjusts a heater assembly to maintain an appropriate temperature at the sensor. The controller utilizes a kernel module that allocates processing resources to the various tasks of a gauge controller module. The kernel module repetitively executes iterations of a loop, wherein in each iteration, all of a set of high priority tasks are performed and one of a set of lower priority tasks are performed. The controller module thereby provides sensor measurement output at precisely periodic intervals, while performing ancillary functions as well.

Abstract: Systems and methods for producing and delivering vapor are disclosed. A vaporizer tank containing a liquid may be heated such that liquid within the tank is heated and vapor generated. The flow of this vapor to a destination may then be regulated. Embodiments of the present invention may control the temperature of this liquid such that a saturated vapor condition is substantially maintained in the vaporizer tank. The vaporizer tank is coupled to a mass flow controller which regulates the delivery of the vapor to downstream components. By substantially maintaining the saturated vapor condition within the vaporizer tank the pressure of vapor at the mass flow controller can be substantially maintained and a stable and consistent flow rate of vapor achieved.

Abstract: A system and method of characterizing or controlling a flow of a fluid is provided that involves a sensor conduit and a bypass. A plurality of fluids may be utilized in the flow control device based on characteristic information of the device generated during calibration thereof. The characteristic information, in turn is based on a dimensionless parameters, such as adjusted dynamic pressure and adjusted Reynolds number.