Abstract: A self-tuning system and method for controlling a process based on a measured parameter comprises modular parameter estimators and parameter controllers which are used in conjunction with the process and which receive as an input the measured parameter. An internal model controller is used as one of the parameter converters and incorporates a feed forward index which is used for gain scheduling. Regression analysis is also used in conjunction with the conventional gain scheduling to more accurate refine the control action. A limiter is also used in conjunction with the regression analysis to avoid an overly high or overly low correction signal for the controller.

Abstract: An apparatus and method for measuring mass flow rate which utilizes a pair of parallel conduits having fixed ends. A driving mechanism is connected between the conduits near their mid-point for applying transverse oscillations to the conduits at a selected frequency. The fluid whose mass flow rate is to be measured is divided roughly equally and supplied through the parallel conduits. A motion sensor upstream of the driving mechanism and another one downstream of the driving mechanism produce signals which have the same frequency as the driving frequency but which lead or lag the driving frequency with regard to phase. This difference in phase is a measurement of mass flow rate. The apparatus can be constructed to self compensate for changes in temperature and/or thermal gradients.

Abstract: A cover for a portion of a control panel module is disclosed. The cover is pivotally attached to an edge of the control panel module and encloses a configuration plug for reprogramming purposes and other switches on the control panel module. The top surface of the cover can be utilized to support the cord which interconnects a reprogramming device to the configuration plug on the control panel module during the programming process. A projection is provided on the top surface of the cover to prevent the cord from slipping off of the cover when the reprogramming device is so interconnected.

Abstract: A tube support for supporting horizontal tubes from an inclined vertical support tube passing between the horizontal tubes. A support button is welded to the vertical support tube. Two clamping bars or plates, the lower edges of one bearing on the support button, are removably bolted to the inclined vertical tube. The clamping bars provide upper and lower surface support for the horizontal tubes.

Abstract: A system for processing and selectively transmitting process signals to a computer and/or a display device is disclosed. The system utilizes a binary full adder (38) to add the incoming signal, in inverted form, to the previously transmitted signal to obtain the difference therebetween. A binary comparator (52) compares the difference with a predetermined value, established by thumbwheel switches (46), and if the difference exceeds the predetermined level, causes the actuation of a flip-flop (54) and a bistable latch (32) permitting the incoming signal to be transmitted to a computer and/or a display device.

Abstract: A thermally bonded fibrous product is composed of a sintered blend of ceramic fibers, low-grade silica material and boron nitride.

Abstract: A method of fabricating a tube having enlarged ends and made of material which can be strengthened by cold working comprises fabricating a pre-form having the overall configuration of the tube but with increased outside diameters and a decreased length. The pre-formed tube is cold forged or cold rolled over its entire length to reduce its outside diameter while maintaining its inside diameter substantially fixed. This elongates the tube and reduces its cross-sectional area. Cold working is continued until the final desired dimensions for the tube are reached. This produces a strengthening effect by cold working over the entire length of the tube.

Abstract: A robot drive for cutting fins having pipes extending on opposite sides therefrom, with the pipes laying in parallel spaced apart rows, comprises a carriage which can move in the longitudinal direction between rows of the pipes. A pair of driven guide rollers is mounted to the carriage for rolling against the pipe of one of the rows. The carriage also carries four spring loaded pressure wheels which bear against the fins of the pipe in an adjacent row so as to press the carriage and guide rollers against the pipe on which the guide rollers roll. A pair of cutting torches or mechanical cutters are connected to the carriage on opposite sides of the guide rollers so that they can cut the fins of the pipes on which the guide rollers roll.

Abstract: A panel indicator (10) which includes a light transmitting indicator rod (16) in engagement with the end (40) of a fiber optic cable (14). A portion of the rod protrudes beyond a retaining housing (12) and has a conical depression (28) formed axially thereof to provide maximum radial dispersion of light from the rod for lateral viewing thereof.

Abstract: A controller for close positioning or modulating control of an electric motor is disclosed. The controller compares a signal representative of the demand on the system with a signal representative of the actual position of the motor or a valve associated therewith, and if the difference between the signals exceeds a "deadband" and no action has been taken within a first time interval, and if the last movement of the valve was in the same direction and a second time interval has elapsed, a motor run pulse is generated. If the last movement of the valve was in a direction opposite to that desired, the motor run pulse is extended to overcome "backlash" resulting from the reversal of motor rotation.

Abstract: A method and apparatus for processing optically generated signals to form a two-wire 4-20 mA signal comprises generating a control signal having pulses at a selected frequency to drive a light emitter which generates light pulses, transmitting the light pulses to a light detector over a transmission line having variable attenuation to form a sensor signal and amplifying the sensor signal in an operational amplifier. The variations and attentuations follow a process variable to be measured. To save power the operational amplifier has a low-current mode into which it is switched whenever no pulse is present in the sensor signal. The amplifier is switched into its high-current mode only when a pulse is present in the sensor signal. Switching is controlled by the control signal for the light emitter. Peaks in the signal from the operations amplifier are sampled and held and then subject to low pass filtering to remove the selected frequency componnent and leave a cyclic filtered signal.

Abstract: A mounting bracket assembly for electronic instrument mounting which also provides for heat dissipation and environmental protection. Side slots in the sides of the mounting bracket permit natural convection air currents to circulate through a plurality of openings in the top and bottom sides of the housing module secured by the assembly to a control panel, but prevent direct entry of liquids, particle contaminents or projections from coming into contact with the electronics contained therein.

Abstract: A position transmitter which can be incorporated in a pneumatic-pneumatic or electro-pneumatic converter, and which readily provides for calibration between a zero position and a maximum position of a device to be actuated by the converter. The invention also provides a virtually non-interacting zero and span or full scale adjustment, for ease of calibration.

Abstract: A technique, including an apparatus, for automatically regenerating a catalyst used in a process for obtaining a product in an exit stream from a raw material in a feed stream of a reactor, comprises determining the concentration of raw material in the feed and exit stream and obtaining a value for the catalyst selectively as a function of the difference between the concentrations. When a selected selectivity is reached, which is indicative of the need for the catalyst to be regenerated, regenerator equipment is activated for regenerating the catalyst in the reactor. To continue the process, the feed stream is transferred to an auxiliary reactor during regeneration of the primary reactor, which contains regenerated or fresh catalyst.

Abstract: A serial communication interface establishes communication to the microprocessor of a transmitter, from a current loop which is powered by a power supply. The microprocessor outputs an analog signal corresponding to a process variable and also can receive a serial communication voltage pulse signal. The analog signal is applied to a current regulating circuit which draws current from the power supply onto the current loop in an amount which is proportional to the process variable. A comparator in the form of an operational amplifier has an output connected to the microprocessor for applying the serial communication voltage pulse signal to the microprocessor. The comparator has one input which is held at a slight negative voltage and another input which is connected to a line of the current loop connected to the negative terminal of the power supply.

Abstract: A roll-and-race pulverizer is disclosed in which the throat vanes are mounted for rotation in the direction of rotation of the grinding ring.

Abstract: An attachment arrangement for attaching a boiler casing to a membrane tube wall utilizes an extension plate which is connected to and extends beyond an edge of the casing. The extension plate and the surface of the casing adjacent its edge define an attachment area which is attached to the tube wall. A slot extends in the casing and through part of the extension plate. The slot is covered by an expansion element having a termination covering the end of the slot. The termination is on the extension plate. The termination of the expansion element extending over the extension plate provides compensation for expansion in the attachment area which avoids deformation and tearing of the casing in this area.

Abstract: A system for mechanically attaching two layers of ceramic fiber material is disclosed. Each layer of ceramic fiber material contains one or more ceramic tubes which are parallel to the interface formed between the layers. Each ceramic tube in one layer is aligned with a ceramic tube in the other layer and ceramic links interconnect the aligned pairs of ceramic tubes forming a mechanical attachment between the layers of material.

Abstract: An apparatus for scanning header tube holes includes a probe assembly designed to engage the surface of the header encircling a header tube hole. The probe assembly includes a spring mounted sensor, in a preferred arrangement, an eddy current probe. A mechanism is provided for supporting and positioning the probe assembly. The mechanism is adapted, in operation, with resilient rings engaging the tube stub. A drive device is provided for imparting axial and circumferential movement to the probe relative to the surface of the hole which is to be inspected.

Abstract: A pneumatic-hydraulic proportional valve actuator system is provided having a relatively simple and adjustable means of achieving two stroking speeds by the hydraulic actuator, high speed in normal operation and low speed for small position adjustments and for the final part of any large position adjustments. This prevents overshoot and instability of the actuator.