Abstract: An early warning system detects the failure of a marine cooling system by monitoring a resistance ground signal generated by a sensing element inserted into the cooling system. An alarm is given upon the detection of an increased resistance value of the resistance ground signal due to cessation or a severe reduction of water flow through the cooling system and hence contacting the sensing element. The sensing element is preferably inserted into the exhaust system portion of a marine engine cooling system and a detection circuit is connected to the sensing element. An alarm signal is generated by the detection circuit if insufficient water flow is present to maintain a low resistance value for the resistance ground signal generated by the sensing element. Such low resistance signal is maintained either by the electrical conduction of the water or the cooling effects of the water on the sensing element.

Abstract: An early warning system detects the failure of a marine cooling system by monitoring the presence of water within the cooling system so that an alarm is given upon cessation or a severe reduction of water flow therethrough. A water sensing element is inserted within the cooling system preferably within an exhaust system of a marine engine cooled by the cooling system and a detection circuit is connected to the water sensing element. An alarm signal is generated by the detection circuit if insufficient water flow is sensed by the water sensing element. The circuit preferably comprises a darlington amplifier having a power input terminal, a power output terminal and a control terminal. A resistor and a capacitor are connected in parallel between the power input terminal and the control terminal of the darlington amplifier, the water sensing element is connected to the control terminal and an audible or visual or combined audible and visual alarm device is connected to the power output terminal.

Abstract: A discontinuity detector detects a sudden change or discontinuity in a medium moving relative to the detector such as a liquid plug in a gas flowing along a conduct, an air bubble in a liquid, or a change form one liquid or gas to another. It has a sensor which senses the discontinuity and a circuit which compensates for gradual changes in the medium or sensor, but responds to the sensed discontinuity. The preferred circuit also determines that the sensor is functioning properly and is properly set up for sensing the discontinuity. The preferred circuit is an analog-to-digital delta modulator which periodically resets a clock pulse counter until a discontinuity is sensed. The clock pulses then increment the counter to a higher-than-normal count to signal the discontinuity. The preferred embodiments are intended for detecting discontinuities in patient gas or liquid supplies in a medical diagnostic or therapeutic instrument.

Abstract: A sewer line backup detection device and alarm are provided which can be installed in place of the cleanout access cap in a conventional sewer line. The device comprises a housing having male connecting threads adapted to fit standard female receptacles which have been used in the past to provide cleanout access to sewer lines, the housing containing alarm means or alarm transmitting means actuated by a pneumatic switch. The pneumatic switch is actuated by a flexible diaphragm which is fitted snugly onto the lower end of the housing which extends into the sewer line. In the event of a blockage of the sewer line, the blocked material exerts pressure on the flexible diaphragm which closes the pneumatic switch thereby setting off an alarm, either locally or at a remote location such as the dwelling from which the sewer line exhausts. The alarm system is utilized especially advantageously in combination with a detention tank located in the basement or lower level of a high rise building.

Abstract: A flow sensing apparatus for providing an indication of the presence of an exiting flow stream from a coal processing plant cyclone includes a probe member disposed in the edge of the flow stream, an electronic sensing circuit cooperatively arranged with the probe member in order to provide either a high or a low level signal, depending upon whether the probe member is being contacted by the exiting flow stream or whether such contact is not being made. A display light is cooperatively arranged with the sensing circuit so as to flicker on and off as the exiting flow stream intermittently and irregularly contacts the probe member. The flickering of the display light indicating proper outlet flow from the coal processing plant cyclone while a constantly on condition of the light indicates that flow is not occurring.

Abstract: A sewer back up warning system includes a pair of electrically-conductive probe rods fixedly securable within a sewer clean out pipe and being in electrical communication with a sewer back up alarm. An electrically-conductive float is hingedly attached to a free end of one of the rods, such float serving to rise in the clean out pipe as a sewer backs up so as to eventually come into contact with the second rod to thus complete the electrical circuit containing the back up alarm. A corrosion check device is also provided which essentially consists of a manually-operable chain pull for effectively bringing the metallic float into electrical communication with the second rod so as to determine the presence of corrosion build up which would prevent the operation of the alarm.

Abstract: A method and apparatus for monitoring flow rate through a conduit. A flow number indicative of the flow rate of a liquid through the conduit is compared with a preselected reference number. The actual liquid flow through the conduit provides a clocking signal which determines the time span during which a count signal, indicative of the intended flow rate into the conduit, is accumulated thereby providing the flow number.

Abstract: A method and apparatus for monitoring char flow in a coal gasifier system cludes flow monitor circuits which measure acoustic attenuation caused by the presence of char in a char line and provide a char flow/no flow indication and an indication of relative char density. The flow monitor circuits compute the ratio of signals in two frequency bands, a first frequency band representative of background noise, and a second higher frequency band in which background noise is attenuated by the presence of char. Since the second frequency band contains higher frequencies, the ratio can be used to provide a flow/no flow indication. The second band can also be selected so that attenuation is monotonically related to particle concentration, providing a quantitative measure of char concentration.

Abstract: A pneumatic remote sensing device having a passageway, a connecting tube connected to the downstream end of the passageway, and blockage means for preventing or permitting the escape of gas from the downstream end of the connecting tube. The passageway includes a venturi section, and means for detecting the pressure within the venturi section and producing an output signal dependent on that pressure are provided. Gas under a supply pressure can be introduced at the upstream end of the passageway. Thus, so long as the blockage means are open, the gas can flow through the passageway and the connecting tube, and the pressure within the venturi section of the passageway will remain low. However, when the blockage means close and prevent the escape of gas from the downstream end of the connecting tube, the pressure in the venturi section rises rapidly and the detector means produces an output signal indicative of the closure of the blockage means almost instantaneously after such closure occurs.

Abstract: A flow rate monitor of solid particles or liquid drops and totalizing count display apparatus including a pulsed infrared light source and receiver forming a monitoring beam of high immunity to ambient light, transversely passing through a sensing chamber. A particular application is wherein the system is applied to the drop chamber of an intravenous set having electronic circuitry for pulsing the infrared light source and pulsing the sensing period of the monitoring beam receiver and producing a drop signal for each drop and a visible light flash for each sensed drop. Circuitry responds to the drop signals for maintaining a count of the number of drops and activating a visible numerical display indicating the drop count according to a selected numeric function, and an additional numeric display is provided adjacent the total count display indicating a selected checkpoint number.

Abstract: Method and apparatus for monitoring the flow of coal from a bunker through a conduit to a coal feeder. A radiation sensitive detector detects the amount of coal present at a zone of the conduit and generates a stream of pulses which is sampled at discrete sample intervals of time to determine whether the conduit zone is empty, partially filled or filled. If the conduit zone is partially filled, a partial alarm is generated, and a determination is made as to whether the conduit zone is empty. If the conduit zone is empty, an empty alarm is generated and the feeder is stopped after a predetermined amount of coal has been deposited on the feeder. If the conduit zone is partially filled and a shut-off valve between the bunker and conduit is closed, a coal build-up alarm is generated. If the conduit zone is filled and the profile of coal at the feeder is not at full profile, a coal hang-up alarm is generated.

Abstract: A nozzle condition monitor for detecting the adequacy of the flow through a fertilizer application nozzle. The monitor comprises a nonmagnetic housing having an up-right passage. Within the passage, a magnetic piston is arranged as the flow may take place along the sides of the piston. Stoppers are arranged to restrict travel of the piston. A magnetic switch is arranged near one end of the up-right passage to be closed when the piston is moved against the stop at that end. Means for detecting the condition of the magnetic switch generate a signal indicative of the adequacy of the flow through the nozzle and therefore the condition of the nozzle.

Abstract: A method and apparatus to monitor a compressible gas volume of one or more hydropneumatic storage tanks of an energy-storing system includes at least one pump to fill the individual storage tanks with hydraulic fluid. The fluid is isolated from the gas volume in each storage tank or unit by a movable partition. The gas volumes of the storage tanks are monitored continuously and free of error for the early detection and signaling of gas volume losses by the use of a minimum of maintenance-free devices. The monitoring is accomplished by determining the state of flow of the hydraulic fluid entering the several hydropneumatic storage tanks while the pump is running. In the event of a coincidence of a running pump and an interruption of the flow to a tank, a loss of gas volume is indicated. A flow monitor having a control contact within each pipeline supplying the hydraulic fluid as well as a signal device for indicating the pump operation is provided.

Abstract: An air flow sensor has a hollow tubular housing partially filled with potting compound and having a printed circuit board mounted in the compound inside the tube. The board is mounted such that two power resistors and a first heat sensing switch mounted on the board are embedded in the potting compound, and a second heat sensing switch mounted on the board above the compound is in contact with the ambient atmosphere. The power resistors are connected in parallel to a power source driving a fan, and the first switch has an actuation temperature selected to activate the switch when the power resistors radiate a selected amount of heat. The second switch also has an actuation temperature due to lack of air flow chosen to activate the switch when the ambient atmosphere reaches the designated temperature.

Abstract: An agricultural implement, such as a cultivator or harrow has fluid sprayers mounted on a boom extending across the implement's width. Adjacent each sprayer, a monitoring device is positioned to signal if the sprayers malfunction. The monitoring device includes a dielectric housing having an upper holder for a wire probe and a detachable lower cover that is hollow and has an open lower end. The cover has an inner chamber and an external skirt. The probe extends through the chamber and out of the lower end to a location near the outer edge of the spraying pattern. It is preferred that the lower portion of the probe be curved and extend in the direction of the fluid being sprayed. Each probe communicates to a respective light mounted on a control box located within the view or supervision of the implement operator so that any malfunction of a sprayer is immediately sensed.

Abstract: The contaminants in the exhaust gas emissions from a motor vehicle such as carbon monoxide (CO) and hydrocarbons (HC) are analyzed within a nondispersive infrared analyzer which includes means for assuring that the vehicle being tested has achieved a predetermined engine speed and that no blockage has occurred in the gas transport system when the measurements are made.

Abstract: A hospital bed or mattress for neonatal infants with a respiration monitor and alarm to detect apnea. No sensor or other appliance is attached to the infant. The bed comprises a base or frame structure with a soft resilient membranous top or cover, e.g., of sheet rubber. The closed air space below the pan is vented to the outside as by a small hole or tube, the average air pressure inside being about atmospheric. The baby's breathing causes slight rhythmic displacements of portions of the body, which in turn transmit small dynamic "recoil" forces proportional to acceleration to the flexible membrane on which the baby rests. The resulting diaphragm-like displacements modulate the air pressure inside. Breathing is sensed by monitoring this acoustic signal by a vented pressure microphone or by sensitive anemometer means connected to the vent. Acoustic and electrical filtering are used to discriminate against higher-frequency signals from the heart-beat and from ambient vibration.

Abstract: A coffee making machine having a calcification indicator system which turns an indicator device on and off to warn of the presence of calcine deposits in the water flow path of a flow heater is disclosed. The coffee machine calcification indicator system includes a glow lamp in a circuit arrangement with a signal flasher circuit. At least a portion of the calcification indicator system is connected in a parallel circuit arrangement with a heater thermostat switch. A calcification indicator switch is actuated at a time dependent upon the conclusion of the coffee making process to disable the operation of the calcification indicator device.

Abstract: A method and apparatus for determining a change of the flow state of a flowable substance by transmitting ultrasonic or ultrasound waves of constant frequency to a spatial region of the substance, receiving ultrasonic waves backscattered by the substance, converting the backscattered ultrasonic waves into a primary signal which is amplitude- and phase-modulated in accordance with the backscattering and demodulating the primary signal in order to obtain a modulation signal. This modulation signal can be divided into a spectrum of signal components of different frequency and possessing pseudo periods which are defined as the time intervals between successive momentary values of the modulation signal, such momentary values corresponding to one another. The time duration corresponding to a predetermined number of pseudo periods is compared with a predetermined time duration.

Abstract: A method and apparatus for parenteral administration of medical fluids has a normally closed clamp on the intraveneous feeding tube which is opened by means of an electromagnetic actuator at a preselected drop frequency rate and closed when a drop is detected by a conductive path established by the drop passing between two opposing electrodes. The electrical system governing the drop counting electrodes also is provided with drop size measuring means which acts to control the preselected drop frequency rate wherein a desired volumetric rate is maintained. Safety features are also provided to prevent excessive or insufficient flow rates.

Abstract: A small diameter transparent visible fluid flow indicator suitable for mounting behind an opening in an instrument panel contains a six-bladed paddle wheel pivoted for rotation by the flow of fluid passing through orifices in the indicator housing. Each of the six blades of the wheel contains a small magnet oppositely polarized from the magnets in the adjacent blades to create alternate magnetic fields that pass through a pickup coil embedded in the housing. The resulting coil voltage is amplified and rectified to control a relay switch. Thus, the liquid flow indicator provides both a visible indication of fluid flow and also controls a switching circuit that may be used as an alarm if the fluid flow stops or varies from some predetermined value.