Abstract: A fluid flow control system that includes a fluid inlet to receive a flow of process fluid and a plurality of fluid outlets. The plurality of fluid outlets include a first fluid outlet and at least one second fluid outlet. The first fluid outlet provides a first predetermined portion of the flow of process fluid, and the at least one second fluid outlet provides the remaining portion of the flow of process fluid. In one embodiment, the control system includes a pressure transducer, first and second multipliers, and first and second flow controllers. The first multiplier multiplies a pressure signal received from the pressure transducer by a first setpoint to control a first flow controller that provides the first predetermined portion of the flow of process fluid. The second multiplier multiplies the pressure signal by a second setpoint to control a second flow controller that provides the remaining portion.

Abstract: Embodiments of the present invention provide a system and method of valve control that eliminates, or at least substantially reduces, the shortcomings of prior art valve control systems and methods. More particularly, embodiments of the present invention provide systems and methods for multi-channel valve control. One embodiment of the present invention includes a system of valve control that comprises a processor, a computer readable medium accessible by the processor and a set of computer instructions that are executable by the processor to output a first signal on a first channel indicating an initial force to be applied to a valve by an actuator and output a second signal on a second channel indicating a control force to be applied to the valve.

Abstract: Embodiments of the present invention provide a diaphragm pressure gauge with an interface printed circuit board (“PCB”) contained in a reference pressure chamber of the diaphragm pressure gauge for receiving signals from one or more sensing elements in the reference pressure chamber. The sensing elements can comprise, for example, piezoelectric strain gauges, piezoresistive strain gauges, capacitor elements or other elements used in determining the deflection in the diaphragm. The interface PCB can be configured to connect the sensing elements to pass-through electrical connections in the housing of the reference pressure chamber. Thus, signals can be communicated from the sensing elements, through the interface board and out of the reference pressure chamber via the pass-through electrical connections.

Abstract: A heater that includes a substantially flat layer of electrical resistance material having a first end and a second end, a first electrical conductor electrically connected to the first end of the substantially flat layer of electrical resistance material, a second electrical conductor electrically connected to the second end of the substantially flat layer of electrical resistance material, and an electrically insulating material surrounding the substantially flat layer of electrical resistance material and electrically insulating the first end of the substantially flat layer of electrical resistance material from the second end of the substantially flat layer of electrical resistance material. The heater may be mounted to a surface of a fluid component and used to heat the fluid component, and where the heater includes an aperture that extends through the electrically insulating material, the heater may be placed between a fluid component and a fluid substrate and used to heat both.

Abstract: A flow restrictor (30) for a mass flow metering device formed of a solid material and slots (32) originating from an outer surface towards inward.

Abstract: An ultrasonic flow meter includes a conduit, a first ultrasonic transducer, a second ultrasonic transducer, and a controller. The first ultrasonic transducer is disposed at a first position about a first portion of the conduit to transmit a first ultrasonic signal and to receive a second ultrasonic signal. The second ultrasonic transducer is disposed at a second position about a second portion of the conduit that is spaced apart from the first position along a length of the conduit to transmit the second ultrasonic signal and to receive the first ultrasonic signal. The controller is configured to cross-correlate the first and second received ultrasonic signals and generate a resulting time-domain signal, analyze the resulting time-domain signal to determine a difference in transit time between the first and second received ultrasonic signals, and calculate a rate of flow of a fluid in the conduit based upon the determined difference.

Abstract: Embodiments of the present invention can include the steps of (i) filtering the indicated flow to derive an intermediate filtered indicated flow, (ii) deriving a weighted first derivative of the intermediate filtered indicated flow, and (iii) outputting a filtered indicated flow comprising the sum of the intermediate filtered indicated flow and the weighted first derivative of the intermediate filtered indicated flow. The indicated flow can be filtered using a FIR, an IIR a running average or other filtering scheme.

Abstract: A resistive bridge sensor circuit that includes a first resistive bridge circuit having a first variable resistance resistor and a second resistive bridge circuit having a second variable resistance resistor. The first and second resistive bridge circuits share at least a portion of a common reference leg that sets a resistance of a first and second variable resistors. The common reference leg or a portion of the common reference leg is alternately switchably connected to one of the first and second resistive bridge circuits.

Abstract: A variable capacitance measuring device can comprise a glass-ceramic insulator having a coefficient of thermal expansion that closely matches the coefficient of thermal expansion of a metallic materials used within the device. The glass-ceramic material may chemically bond to the surfaces of the metallic materials to provide a hermetic seal and eliminate the need for a separate glass seal or grooves within the electrode assembly. Additionally, a single-piece electrode assembly can be used instead of a separate electrode assembly (for the electrical feedthrough) and electrode. A shim may be used during the formation of the insulating material to reduce the likelihood of the insulator adhering to surfaces of the electrode portion during the manufacturing process. Also, separate bake-out and getter activation cycles may be combined into a single heat cycle.

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 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: A gas panel comprising a first gas stick, a second gas stick, and a first manifold. The first gas stick has a first flow path that includes a first plurality of ports formed in a common plane, and the second gas stick has a second flow path that includes a second plurality of ports formed in the common plane. The first manifold has first and second ports formed in the common plane, the first port being fluidly connected to one port of the first plurality of ports of the first gas stick, and the second port being fluidly connected to one port of the second plurality of ports of the second gas stick. A thermally and vibrationally insulating mounting assembly may be used to mount the first and second gas sticks to a mounting plate.

Abstract: A fluid flow control system that includes a fluid inlet to receive a flow of process fluid and a plurality of fluid outlets. The plurality of fluid outlets include a first fluid outlet and at least one second fluid outlet. The first fluid outlet provides a first predetermined portion of the flow of process fluid, and the at least one second fluid outlet provides the remaining portion of the flow of process fluid. In one embodiment, the control system includes a pressure transducer, first and second multipliers, and first and second flow controllers. The first multiplier multiplies a pressure signal received from the pressure transducer by a first setpoint to control a first flow controller that provides the first predetermined portion of the flow of process fluid. The second multiplier multiplies the pressure signal by a second setpoint to control a second flow controller that provides the remaining portion.

Abstract: A method and apparatus for blending and supplying process materials. The method and apparatus are particularly applicable to the blending of ultra-high purity chemicals, the blending of abrasive slurries with other chemicals for the polishing of semiconductor wafers, and high-accuracy blending of chemicals. The apparatus may include a dispensing subsystem that supplies process materials to a mixing subsystem where they are blended with a static mixer. The method may include supplying process materials with a dispensing subsystem and blending the process materials in a static mixer.