Abstract: Application interface software provides communication between a network of computer nodes and user applications of a host processor. Interpreters or gateways are used between the host processor and the network of computer nodes. The application interface software employs a redundancy routine to ensure host access of computer node data through the gateways. The redundancy routine changes access of computer node data from one gateway to a second gateway during times of dysfunctioning of the one gateway. The redundancy routine changes access in a manner which is transparent to the host processor. A database is employed to hold computer node data for direct access by the host processor. The redundancy routine ensures the latest computer node data values to be reflected in the database.

Abstract: A monolithic flowtube for use with an electromagnetic flowmeter includes an inner portion formed of an improved purity dielectric material having a reduced number of mobile ions, a pair of electrodes adjacent the exterior surface of the inner portion and capacitively coupled thereto, and an outer layer of ceramic material adjacent the exterior surface of the inner conduit and electrodes. A method of manufacturing the flowtube includes the steps of forming a dielectric material into a substantially tubular conduit, depositing a conductive material, preferably a refractory metal, onto the exterior of the tubular conduit, forming an outer layer of ceramic material over the tubular conduit, and firing all components simultaneously in a reducing atmosphere to form a monolithic flowtube body.

Abstract: An adaptive PID.tau..sub.d controller has a proportional derivative section that generates an error signal representing an error in the control signal, particularly, as a function of (i) a time rate of change of the controlled variable signal and (ii) a difference between the controlled variable signal and a predetermined setpoint. A summation element sums that error signal with a time-delayed integral signal to generate a summation signal. That summation signal, in turn, is filtered by the aforementioned adaptive noise filter to generate a manipulated variable signal, which is selectively applied to the process by an output section. A feedback element processes the manipulated variable signal to generate the time-delayed integral signal, referred to above. That processing includes time-delaying the manipulated variable signal an mount substantially equal to the deadtime of the process, .tau..sub.

Abstract: An analyzer for detecting a selected chemical (such as oxygen) in a process fluid includes a plurality of electrodes that are separated from the fluid by a membrane that is permeable to the selected chemical, each of the electrodes when energized producing a signal in response to the selected chemical in the fluid. The selected chemical level in the process fluid is determined based on the signal produced by a first one of the electrodes, and the determined level is used with the signal produced by a second one of the electrodes to detect whether the membrane has become faulty (e.g., fouled by materials in the process fluid).

Abstract: A capacitive differential pressure sensing device with pressure overrange protection and a method of making the same are described. The device employs a doped polysilicon diaphragm overlying a cavity in a doped single crystal silicon wafer having a port extending into the cavity from the opposite side. The cavity floor serves as an overrange protector.

Abstract: A control system for a process machine, preferably an injection molding machine, and having an improved control system architecture. The system includes a machine controller which is coupled to and drives the machine and a separate display/operator interface. Both of the units are independently processor driven and function in a decoupled fashion. A communication bus links the display/operator interface and the machine controller, and standardized messages are communicated bidirectionally on the bus. By means of that sole linkage, the machine controller is utilized to drive the machine while the display/operator interface emulates a tightly coupled control panel, but operates independently, except for the communication of messages on the data bus. Preferably, a power supply for the display/operator interface is mounted in the machine controller enclosure and coupled to the interface by a power supply cable.

Abstract: An improved system for tuning process control equipment applies a load change of amplitude .delta.q to the process to effect a change in it and, therefore, in the controlled variable. Monitoring the response of the controller to that change, the system identifies an observed overshoot, OVS.sub.o, in the manipulated variable signal. From that overshoot signal and a predetermined theoretical overshoot signal, OVS.sub..tau., the system generates an optimum gain, K.sub.opt, as a function of the mathematical expression K.sub.opt =K*(1+OVS.sub..tau.)/(1+OVS.sub.o), where K is the current gain of the automatic control subsection, OVS.sub.o is the observed overshoot, and OVS.sub..tau. is the predetermined overshoot.

Abstract: A microporous, photoprocessable, moderately hydrophilic material on which metal can be deposited directly using electroless plating techniques, and its use in preparing printed wiring boards and circuit components.

Abstract: A monolithic flowtube for use with an electromagnetic flowmeter includes an inner portion formed of an improved purity dielectric material having a reduced number of mobile ions, a pair of electrodes adjacent the exterior surface of the inner portion and capacitively coupled thereto, and an outer layer of ceramic material adjacent the exterior surface of the inner conduit and electrodes. A method of manufacturing the flowtube includes the steps of forming a dielectric material into a substantially tubular conduit, depositing a conductive material, preferably a refractory metal, onto the exterior of the tubular conduit, forming an outer layer of ceramic material over the tubular conduit, and firing all components simultaneously in a reducing atmosphere to form a monolithic flowtube body.

Abstract: A pressure sensor sub-assembly (18) has a solid-state sensing element (22) mounted on a laminated ceramic substrate (20) and has the electrical signal contacts (22a) on the sensing element electrically connected to connector pins (24) on the substrate. A manufacturing process can fabricate a batch of sub-assemblies on a substrate structure that is sub-divided to form the separate sub-assemblies. The sensor sub-assemblies can be tested, and graded, before or after the sub-division step, and then each mounted in a housing.

Abstract: A method is provided for accurately determining the complexing capacity (or free HF concentration) of a pickling liquor. A sample of pickling liquor is obtained and an excess of ferric ion is added thereto to complex with all of the free HF in the sample. A back titration is performed to determine the residual free ferric ion. The difference between the amount of ferric ion added and that found by the titration is related to the free HF in the original sample.The method is useful in conjunction with an automated, on-line system which periodically monitors a pickling bath and makes any necessary adjustments thereto.

Abstract: A rigid central manifold block defines a coaxial inlet and outlet of the flowmeter and supports at least one continuous conduit loop substantially encircling the block and having its inlet and outlet ends closely spaced and rigidly connected to the block. Preferably, the loop includes a straight section perpendicular to the inlet and outlet ends. Dual drive means are preferably provided for oscillating the straight section back and forth about its perpendicular bisector and complementary position detectors employed at or near the opposite ends of the straight section, preferably at the same location as the drive units, provide readouts which are combined algebraically and synchronously demodulated to yield a Coriolis-related output indicative of mass flow. Preferably, a second loop, identical and parallel to the first, is supported by the same block. The block is channeled to serve as a manifold and interchangeable manifolds are disclosed for series and parallel flow through the two loops, respectively.

Abstract: A method for patterning a tape to which an integrated circuit may be bonded including providing a tape having a top layer of unexposed film which, when exposed in an interconnection pattern and developed, acts as a mask for processing a photoprocessable layer of the tape to provide conductive portions in an interconnection pattern on the tape.

Abstract: A CAD driven photoplotter selectively exposes a photographic imaging layer without affecting the underlying UV sensitive resist on a substrate to make a printed wiring board, for example. The image layer is developed on the board and used as an in situ mask for the underlying UV resist during exposure to UV. After UV exposure, the image layer is peeled off to allow conventional processing of the resist. The in situ mask is preferably applied in the form of a baseless, high contrast, high gamma emulsion layer bonded to the protective cover sheet over the uncured resist. To facilitate application, the emulsion layer is carried by a release paper which is removed before photoplotting. After UV exposure, the cover sheet and emulsion layer are integrally peeled from the resist.

Abstract: A token passing media access protocol provides distributed time scheduling. The token provides an indication of each time at which a network device is to perform a cyclic or time critical operation. The token also provides an indication of system time to enable all devices on the network bus to be synchronized. The format of data transmissions on the network bus employs a shortened device address when referencing the device as a source. The source address corresponds to a unique portion of the device address.

Abstract: A language structure and translator specifically adapted for use in constructing computer programs for controlling chemical and physical processing. The translator converts to compilable code programs written as statements expressing control intentions or results. Each textual function and statement is expressed as a data structure which expresses the function, as configured, and the state and values most recently calculated for the relevant variables. Provision is made for treating the program structure (i.e., control connections, program order and components, etc.) as a part of the dynamic state of the application. Graphical symbols, or icons, are employed to draw the eye to critical features in the control program and to lead the eye through critical interrelationships among the several commands of a complicated control system. At the same time, the translator treats the keystrokes generating these icons as statements (i.e.

Abstract: An improved setpoint control system is disclosed for use in conjunction with process control equipment. The system generates signals representing a statistical characteristic of batches, or subgroups, of monitored values of a controlled variable. From these statistical characteristic signals, the system generates an optimum setpoint signal as a sum of a specification limit and a scaled value of the standard deviation of averages of each of a plurality of batches controlled variable values.

Abstract: An external electrode seal assembly (10) for magnetic flow meter tubes (12) is disclosed. The assembly includes a polymeric gasket (36) compressed between a head portion of an electrode (17) and an external seal area (18) of a ceramic tube (12). A stem portion (30) of the electrode extends from the head portion (28) to the interior wall (26) of the tube and is in contact with process fluid flowing through the tube. A clamp assembly (42) compresses the polymeric gasket (36) between the head portion (28) of the electrode (17) and the ceramic tube (12) to form the seal.

Abstract: An overpressure-protected, differential pressure sensor (37) is formed by depositing diaphragm material (24) over a cavity (23) formed and filled with sacrificial material (22) into a front surface of a substrate. The sacrificial material (22) is then removed to create a free diaphragm. The floor of the cavity (23) defines a first pressure stop to limit the deflection of the diaphragm in response to pressure applied to the top of the diaphragm. A port (33) is created to allow pressure to be applied to the bottom side of the diaphragm (24). An optional second pressure stop, which limits the deflection of the diaphragm in response to pressure applied to the bottom side of the diaphragm, is formed by bonding a cap (35) to standoffs (34) placed around the top of the diaphragm. The standoffs are spaced to allow pressure to be applied to the top of the diaphragm.

Abstract: The present invention relates to a path management system for regulating equipment resources which moves process material through a process system. The process system includes a control procedure for implementing a specific process application. The path management system includes a path editor for building different path specifications, each of which defines an equipment set and sequences of equipment operations for a specific process application. A database is interconnected to the path editor for storing the plurality of path specifications built by the path editor. The path management system further includes a path selector for selecting a single path specification for the specific process application from a plurality of path specifications stored in the database. The path selector then validates the availability of equipment resources identified by the selected single path specification at a particular instant in time.