Abstract: A reserve activated electrochemical cell in a battery embodiment uses a tubular electrolyte storage compartment arranged in a concentric spiral having similar diameter turns thereof located on a common axis. The tubular spiral is assembled concentrically with a battery plate stack container in a volumetrically efficient package with a first end of the spiral having an outwardly projecting flange located adjacent to one wall of the stack container. An intermediate annular spacer is located between the flange and the wall of the stack container to provide a fluid-tight seal therebetween, to define a fluid channel therethrough and to separate different materials forming the stack container and the electrolyte storage spiral. A first rupturable diaphragm is attached with a fluid-tight seal across the inner diameter of the first end of the tubular spiral facing the battery stack to maintain hermeticity therein.

Abstract: A sensor and control module have a housing with an internally mounted printed circuit board which supports a sensing element located in an outwardly projecting hollow portion formed at the lower part of the housing. The projecting portion is prism-shaped and includes air intake slots at its bottom side to enable external air to reach the element. The upper side of the projecting portion which is adjacent to control elements on the module is sealed. The housing is provided with an internal air passage adjacent to the printed circuit board between the air intake slots and air exit slots at a top side of the housing spaced from the control elements. In one embodiment, the module is a thermostat, and the sensing element is a temperature responsive resistor used to sense air temperature.

Abstract: A reserve activated electrochemical cell with a cell condition checking apparatus uses a sealed electrolyte storage reservoir having an expandable pressurized capsule within the reservoir for pressurizing the electrolyte. The reservoir is provided with a rupturable diaphragm providing a fluid-tight seal across an opening in a wall of the electrolyte reservoir. The reservoir is formed integrally with a container for a reserve cell electrode assembly or stack with the wall therebetween containing the rupturable diaphragm. A selectively operable lance is arranged with a pointed first end adjacent to the diaphragm and a second or opposite end projecting out of the cell stack container. A resilient bellows is attached externally of the cell stack container to cover the projecting end of the lance while providing a fluid-tight seal to the external wall of the cell stack container.

Abstract: A reserve activated electrochemical cell has a sealed electrochemical fluid, e.g., an electrolyte, storage reservoir having an expandable free-floating capsule within the reservoir for selectively pressurizing the fluid. The reservoir is provided with a rupturable diaphragm arranged as a fluid-tight seal across an opening defining a fluid conduit through a wall of the reservoir. The reservoir is formed integrally with a container for a cell electrode assembly or stack, e.g., opposite polarity battery electrodes, with a wall therebetween containing the rupturable diaphragm. A selectively operable gas generator within the reservoir is connected to one end of the expandable capsule for providing a gas pressure therein to expand the capsule. The gas generator is operated by a signal applied to the gas generator by electrical connecting leads passing through fluid-tight seals in a wall of the reservoir.

Abstract: An apparatus for recording a plurality of variable analog signals individually and sequentially scanned during the recording operation. The analog signals are digitized, and the digital values multiplexed into a microprocessor which uses a stored program to determine significant changes in the scanned analog input and to store only meaningful data representing a significantly changed analog input in a buffer memory for subsequent recording on a recording chart. Specifically, the apparatus provides a selection of input values to be recorded whereat the recorded input values differ by a predetermined amount with respect to the measured value or the time basis of a recording chart. The buffer memory serves to match the velocities between scanning of the inputs and the printing of the measured variables since the inputs are scanned at a rate which is much higher than the print rate of the recorder to allow a follow-up of the measured variable which provides equidistant recording of the measured values.

Abstract: A reserve activated electrochemical cell with a cell condition checking apparatus uses a sealed electrochemical fluid, e.g., an electrolyte, storing reservoir having an expandable pressurized capsule within the reservoir for pressurizing the fluid. The reservoir is provided with a rupturable diaphragm arranged as a fluid-tight seal across an opening in a wall of the reservoir. A selectively operable lance is arranged with a pointed end adjacent to the diaphragm for activating the cell by piercing the diaphragm to release the fluid into the electrode assembly. A reservoir leak indicator is located in the reservoir to provide an indication of a leakage path between the pressurized capsule and the fluid stored in the reservoir allowing a migration of the fluid into the capsule. In a first embodiment of the reservoir leak detector, a visual indication of fluid leakage is provided through a transparent window in a wall of the reservoir by a visual change in a fluid reactive substance located in the capsule.

Abstract: A relay driver circuit which protects a relay against contact degradation. A detector circuit within the relay driver circuit receives an AC signal at a random phase. The detector circuit correspondingly provides a detector signal to a threshold responsive circuit, such as a timer, which drives the relay. The threshold responsive circuit responds substantially the same to a detector signal provided on a positive cycle and to a detector signal provided on a negative cycle. The relay driver circuit is applied to control a blower fan in an air conditioning system.

Abstract: An anti-backflow valve to prevent back-flow of water within a water supply line comprises a cross-shaped housing arranged symmetrically with respect to a vertical center axis. A diaphragm is clamped between the housing and a cover and acts via a valve stem upon a relief valve. Parallel to the valve stem and located on each side of it are two check valves arranged within bores of the housing. Both check valves as well as the relief valve are arranged in a plane containing an inlet and outlet of the housing to produce a compact and symmetrical configuration which is easily inserted into a water supply line.

Abstract: A multiplexer having a plurality of semiconductor solid state input switches arranged to be connected to respective input signal sources and arranged in groups of input switches with a plurality of the switches in each group, a plurality of selectable leakage current shunting circuits with each circuit being connected by a leakage current control switch to a respective one of the groups of the switches to provide a shunt path for leakage currents through the switches in a corresponding group and a switch control for selectively operating the solid-state switches to connect a selected one of the input signal sources in a selected one of the groups of sources to an output of the multiplexer and the leakage current switches in the non-selected groups to connect each of the solid-state input switches in the non-selected groups to the respective ones of the current shunting circuits.

Abstract: An absolute pressure transducer includes a hollow glass tube supporting across one end thereof a differential pressure responsive semiconductor plate having piezoresistive elements diffused therein and an evacuated sealed chamber within the tube exposed to the plate. A method for making the transducer and providing the evacuated chamber within the tube adjacent to the plate includes the steps of mounting the plate across the end of the tube to form a first fluid-tight seal therewith, inserting a loose glass plug within the tube to define the chamber, exposing the interior of the tube to a vacuum, concurrently heating the tube in the vicinity of the plug to allow the heated tube wall to constrict around the plug in response to the internal vacuum and to fuse with the plug to form a second fluid-tight seal therewith and allowing the tube and plug to cool to trap the vacuum in the chamber.

Abstract: A method for improving cooling of a compressor element used in an air conditioning system and having a refrigerant compressor and associated drive motor hermetically sealed in a fluid-tight shell includes the steps of detecting an excessive increase in the temperature of the compressor element, intermittently operating the system during the excessive temperature detection with a superheat of a refrigerant in the system below zero superheat degrees to concurrently allow liquid refrigerant to enter the shell to enhance the cooling of the compressor apparatus by the latent heat of vaporization of the liquid refrigerant and terminating the intermittent operation and the admittance of the liquid refrigerant into the compressor element upon a detection of a desired temperature of operation of the compressor element.

Abstract: An overvoltage control circuit for a reserve battery includes a current limiting resistor connected in series with a thermal-lag type circuit interrupter such as a thermal-lag fuse or circuit breaker. The series combination is connected across a selectively activatable reserve battery which is connected across an electrical load to be energized by the battery. A high current drain through the circuit interrupter and the resistor during an initial activation of the reserve battery is effective to stabilize the output voltage of the battery at a level below a desired working limit of battery potential without an overshoot of the working limit. Subsequently, the current drain operates the circuit interrupter to isolate the limiting resistor to interrupt the current drain and allow the battery output to reach a level approximating the working limit.

Abstract: A printed circuit board mounted rotary electrical switch has a rotatable electrical contact carrier mounted for rotation within a cup-shaped housing and carrying indexing and rotation limiting devices cooperating with the housing. An electrical contact strip is carried by the rotatable carrier for selectively providing a direct electrically conductive bridge between pairs of a plurality of projecting electrical contacts attached to the circuit board and to corresponding printed wiring on the circuit board. The housing is attached to the circuit board by screws threaded into the circuit board through perforated ears projecting from respective sides of the housing. The carrier and the housing are made of an electrically non-conductive material to protect the strip and the contacts from extraneous electrical paths.

Abstract: A transmitting/receiving circuit for an acoustic transducer (W1, W2) wherein the transmitting transducer (W1) is sequentially controlled by different modulated carrier frequencies (f1, f2), where the control is first matched to the inherent frequency (f1) of the transducer (W1) and afterwards the control of the transducer (W1) is by a frequency (f2) outside of the inherent frequency. During a signal reception by the receiving transducer (W2), a lock-out of a phase-locking circuit (PLL) is detected, where with an object to be measured is in a near range an active lock-out due to the frequency shift of the reception signal outside a frequency bandwidth of the phase-locking circuit is detected, and where with an object to be measured is in a far range, a passive lock-out is detected due to the fact that the reception signal amplitude falls below a noise level.

Abstract: A method for process control to minimize hunting using a controller wherein a PID arithmetic operation is performed with respect to a deviation of a setting parameter and a processed variable fed back from a process, and a resultant manipulation variable is applied to the process including the steps of monitoring the waveforms of the setting parameter and the processed variable from the process to obtain an oscillation period of the deviation, identifying process characteristics of the process, obtaining a phase angle of a frequency response of an open-loop transfer function of a system from the oscillation period and the process characteristics, and detecting a hunting of the process by the magnitude of the phase angle.

Abstract: A sensor fault detector for detecting a missing or shorted environment condition sensor of a plurality of sensors includes a sensor circuit for supplying a concurrent output signal from each sensor, a reference voltage circuit for supplying a predetermined reference voltage, a plurality of comparators, each of the comparators concurrently comparing a repective one of the output signals with the reference signal to produce a corresponding comparator output signal representative of a predetermined relationship between the compared signals assure the presence of properly working and connected sensors and a monitoring circuit responsive to the concurrent effect of output signals from all of the comparators to produce a control signal representative of a concurrent properly working and connected state of all of the sensors.

Abstract: A pressure transmitter assembly includes a laminated ceramic structure for providing fluid passages as well as a support for a pressure sensor, electronic circuitry, fluid barrier diaphragms and input process fluid connections. The laminated structure is comprised of a plurality of co-fired ceramic layers having the fluid passages molded therein to enable fill fluids within the assembly to apply input pressures as a differential pressure across the pressure sensor. In one embodiment of the invention, three ceramic layers are used while a second embodiment uses four layers with an overload diaphragm captured between two of the layers. The laminated ceramic structure can be extended in either embodiment to include an outer ceramic circuit board which is bonded with a fluid-tight interface with an adjacent one of the other ceramic layers.

Abstract: A two-wire transmitter having a detecting section for detecting a physical variable to be measured to produce a detection output, first and second constant voltage devices connected in series with a two-wire transmission path, a signal processor driven by a voltage supplied by the first constant voltage device for converting the detection output into representative serial pulse signals and a switching circuit which is connected in parallel with the second constant voltage device and is turned on and off by the serial pulse signals to produce corresponding output signals from the transmitter on the two-wire transmission path by utilizing a current flowing in the two-wire transmission path while enabling the transmitter to connect in a single loop with another two-wire transmitter.

Abstract: A compensation circuit for sensor lag uses a sensor temperature signal modification circuit to provide a modified sensor temperature signal for subsequent use in controlling the sensed temperature. The compensation circuit digitally compares a current sensor temperature representative signal and a sensor temperature signal at a last or preceeding sample time to produce a difference signal which is converted to a sensor slope signal and is multiplied by a sensor time constant. The resulting signal is passed through a filter to eliminate transient effects and is summed with the original sensor temperature signal to provide a sensed temperature signal for control of the temperature whereby the sensed temperature is a better estimate of the actual environmental temperature controlled by a thermostat utilizing the sensed temperature signal.

Abstract: A communication apparatus inserted in parallel in a two-wire communication line of a two-wire measuring instrument which consists of a transmitter and a receiver connected to each other through the two-wire communication line and transmits a process value detected by the transmitter to the receiver as an analog signal, the communication apparatus being adapted to communicate with the transmitter, comprising a switching device for separating a closed loop constituted by the transmitter and the receiver into a first loop including the transmitter and a second loop including the receiver, a power source for supplying power to the transmitter in the first loop, and dummy output means for outputtting a dummy signal to the receiver in the second loop.