Abstract: An oil pressure warning system for an outboard motor for detecting and alarming an abnormal oil pressure of an internal combustion engine, the system including a first oil pressure switch which generates an ON signal when the oil pressure is less than or equal to a first predetermined oil pressure, and a second oil pressure switch which generates an ON signal the oil pressure is less than or equal to a second predetermined oil pressure set higher than the first predetermined oil pressure. The abnormality of oil pressure is detected and alarmed based on the ON signal of the switches. The first and second predetermined oil pressures are determined based on an oil pressure characteristic of a (possible) maximum oil temperature (under which the engine has been warmed up) set relative to the engine speed, thereby ensuring to detect and alarm the abnormality of oil pressure under any engine speed and any oil temperature.

Abstract: A vacuum chamber (22) of a pneumatically operated servo unit (30) of a motor vehicle is subjected to vacuum by an electric suction pump (28). In order to monitor the vacuum chamber (22) and the electric suction pump (28), the invention proposes that a starting pressure in the vacuum chamber (22) be determined. In addition, after a certain time interval, an ending pressure in the vacuum chamber (22) is determined. Furthermore, the difference between the ending pressure and the starting pressure is calculated and compared to a limit value. If this difference falls below the limit value, a signal is generated, in particular a warning and/or alarm signal.

Abstract: A method and apparatus for detecting a restricted or bypassed transmission oil filter by providing pressure transducers on both sides of the oil filter whereby the pressure differential will indicate the extent of filter restriction. A first alarm is activated at a first pressure differential to indicate a restricted filter and the need for filter replacement. A second, higher level, alarm is activated to indicate the filter is bypassed and the engine is reduced in speed to allow the pressure and the pressure differential to drop to the point that the filter is no longer bypassed. This enables the vehicle to be operated with limited capabilities to allow the vehicle to be driven to the shop for filter replacement. If the lowered engine speed is insufficient to reduce the pressure differential to stop the bypass, then the engine speed is further reduced to a low idle and the transmission shifted to neutral.

Abstract: An oil maintenance indicator for recording one or more parameters indicative of when an engine oil filter has been changed. The maintenance indicator includes a sensor that measures oil pressure of an engine at start up. A comparator compares an output provided by the sensor to known parameters to determine whether the oil filter has been changed. A recorder coupled to the comparator records one or several parameters indicative of when the oil filter has been changed.

Abstract: A flight control indicator for an aircraft, intended to supply the engine pressure ratio, includes acquisition and processing units (2, 3) which determine the actual value of the engine pressure ratio and a display unit (4) provided with a dial (6) and with a needle (7) whose position on the dial (6) corresponds to the actual value of the engine pressure ratio. Moreover, the acquisition and processing units (2, 3) determine minimum and maximum values for the engine pressure ratio, and the display unit (4) presents on the dial (6) a circular sector (8) which is delimited by two radii (8A, 8B) whose positions correspond respectively to the minimum and maximum values for the engine pressure ratio.

Abstract: This invention is relating to a barbed wire, of which one strand is a conventional iron wire, and the other strand is a conductor embedded plastic wire that includes a conductor covered by a sturdy plastic insulator. The purpose of using a conductor embedded plastic wire is that it can be used for an alarm system where high security is demanded. This invention provides easier manufacturing process and simpler method for the application of the barbed wire to an alarm system than the products of prior art of U.S. Pat. No. 4,317,955. Therefore, this invention is less expensive to produce the product.

Abstract: An oil pressure switch failure detection system for an outboard motor, having a first oil pressure switch which generates an ON signal indicating that the oil pressure is less than or equal to a first predetermined oil pressure and a second oil pressure switch which generates an ON signal indicating that the oil pressure is less than or equal to a second predetermined oil pressure which is set higher than the first predetermined oil pressure. In the system, by discriminating whether the generated signals of the first and second oil pressure switches are equal to be expected signals expected under operating conditions of the engine, it is determined whether at least one of the first and second oil pressure switches fails. With this, it become possible to detect failure of the first and second oil pressure switches, accurately.

Abstract: A reliable capacitive oil deterioration and level sensor has a conductive housing member that includes a conductive shielding member defining a ground electrode, and a conductive inner member defining a measuring electrode. The shielding member protects the sensor from moving objects that could adversely affect its performance. The housing member is adapted to provide a fluidic connection between an oil container and a space between the ground electrode and the measuring electrode. The sensor also includes electronics adapted to employ this capacitor geometry to generate signals indicative of a degree of deterioration and a level of the oil within the gap. The electronics further include at least one isolating capacitor to eliminate a flow of current between the electrodes that may cause a build up of material on the two electrodes that define the capacitor. This build up of unwanted material may cause an undesirable effect in the sensor output signal.

Abstract: Several sensors are provided for determining one of a number of physical roperties including pressure, temperature, chemical species, and other physical conditions. In general, the sensors feature a resonant circuit with an inductor coil which is electromagnetically coupled to a transmitting antenna. When an excitation signal is applied to the antenna, a current is induced in the sensor circuit. This current oscillates at the resonant frequency of the sensor circuit. The resonant frequency and bandwidth of the sensor circuit is determined using an impedance analyzer, a transmitting and receiving antenna system, or a chirp interrogation system. The resonant frequency may further be determined using a simple analog circuit with a transmitter. The sensors are constructed so that either the resonant frequency or bandwidth of the sensor circuit, or both, are made to depend upon the physical properties such as pressure, temperature, presence of a chemical species, or other condition of a specific environment.

Abstract: A real-time maintenance alert system and method for use in a heavy-duty truck having an engine controller with memory are provided. The system includes a sensor operative to indicate an engine condition from the group consisting of: oil filter restriction, air filter restriction, fuel filter restriction, oil level, and coolant reserve tank fluid level. Control logic at the engine controller processes the sensor signal to determine a real-time fault condition, when appropriate.

Abstract: A warning system for an outboard motor, includes: an oil-pressure switch for outputting the low-pressure state signal when the oil pressure of the lubricating oil lowers than a fixed reference pressure; a control device for controlling the operation of the warning device; a determining device which judges whether the low-pressure state signal continues to be output longer than the predetermined delay time and determines that the oil pressure is abnormal if the judgment is affirmative; and a control device for actuating the warning device so as to perform a warning operation when the determining device has determined that the oil pressure is abnormal.

Abstract: Several sensors are provided for determining one of a number of physical properties including pressure, temperature, and other physical conditions. In general, the sensors feature a resonant circuit with an inductor coil which is electromagnetically coupled to a transmitting antenna. When an excitation signal is applied to the antenna, a current is induced in the sensor circuit. This current oscillates at the resonant frequency of the sensor circuit. The resonant frequency and bandwidth of the sensor circuit is determined using an impedance analyzer, a transmitting and receiving antenna system, or a chirp interrogation system. The resonant frequency may further be determined using a simple analog circuit with a transmitter. The sensors are constructed so that either the resonant frequency or bandwidth of the sensor circuit, or both, are made to depend upon the physical properties such as pressure, temperature, presence of a chemical species, or other condition of a specific environment.

Abstract: A portable alarm system for alerting a central station of an emergency. The portable alarm system includes a central unit for monitoring a desired area and a remote control unit for activating and signaling the central unit. The central unit includes a detector for detecting an emergency situation and generating a signal in response thereto, a processor for receiving the detection signal and generating an alarm signal in response thereto, a receiver for receiving an emergency signal and providing the emergency signal to the processor and an alarm for alerting the central station upon receipt of one of the alarm signal and emergency signal. The remote control unit includes a device for generating the emergency signal upon receipt of a user generated command and a transmitter for transmitting the emergency signal to the receiver of the central unit.

Abstract: An apparatus (10) comprises an inflatable vehicle occupant protection device (12) and an inflator (20) for inflating the inflatable vehicle occupant protection device. The inflator (20) has a wall (32) defining a chamber (40) in the inflator. Inflation fluid is stored at a predetermined pressure in the chamber (40). The apparatus (10) further comprises a first device (102) for generating electrical energy. The first device (102) is located in the chamber (40). A second device (106, 108) senses a change in the predetermined pressure and transmits a signal indicative of the change in the predetermined pressure through the wall (32). The second device (106, 108) is located inside the chamber (40) and is electrically connected to the first device (102). A third device (122, 124) senses the signal. The third device (122, 124) is located outside of the chamber (40).

Abstract: An improved speed reducer assembly is provided. The assembly comprises an input shaft, an output shaft and a gear train interfacing the input shaft and the output shaft to effect a desired angular velocity ratio between the input shaft and the output shaft. A housing defines an interior area in which the gear train is disposed, the housing being configured to hold lubricant within the interior area. A pressure sensing device is mounted on the housing in communication with the interior area. The pressure sensing device is configured to output a pressure signal responsively to fluid pressure within the interior area. A second housing may be provided to sealingly enclose a portion of the pressure sensing device outside the speed reducer housing.

Abstract: A safety cap for containers under steam pressure contains internally a diaphragm that is actuated by the pressure of steam in such a way as to break the mechanical connection between a closure member forming part of the cap and screwed onto the container, and a knob forming part of the cap and by means of which the latter can be screwed on and off. In order to increase the safety features of the cap, the latter is fitted with a manometer, incorporated in the cap and readable from the outside, which detects the pressure of steam in the container.

Abstract: A digital signal obtained by A/D converting an output of a thermal type air flow meter is supplied along two paths. After a time constant is obtained in one path, inverse-transformation is performed to obtain an error together with an output of the other path. The inverse-transformed signal is linearized on the basis of the characteristic of the thermal type air flow meter, and a direction of flow is determined.

Abstract: The invention is directed to a method of detecting and documenting exhaust-gas relevant malfunctions of a vehicle equipped with an internal combustion engine utilizing onboard equipment. Malfunctions are detected by a sensor device and evaluated in a circuit unit. The malfunction is displayed by a warning lamp (fault announcement) and is stored in a fault memory. A pressure measurement in the fuel loop is made and the output as well as the storage of the fault announcement is made in dependence upon the measured pressure. This is done to differentiate fault announcements based on a fuel tank run to empty.

Abstract: A system for detecting leaks in a hydraulic system. The system shuts down the hydraulic system if a leak is detected and notifies individuals in the area that a leak has occurred. The leak detection system has sensors for measuring hydraulic system parameters and a computer for detecting abnormalities in the system based on values returned by the sensors. Sensors used in the example leak detection system include an RPM pickup, a pressure transducer, a flow meter and an hydraulic fluid level and temperature switch. Outputs of the sensors are analyzed by the computer to determine if the hydraulic system has a leak. If a leak is detected, the computer sends response signals to a device for engaging or disengaging the prime mover from the hydraulic pump and to another device for actuating a valve to stop hydraulic fluid flow from the reservoir. The computer may also send indicator signals to a display console for activating a warning light, a buzzer or a display.

Abstract: A leak diagnosis system for an evaporative emission control system executes a correction process of diagnosis decision value. When the purge control of the evaporative emission control system is not executed, a purging line of the system is set in the atmospheric condition for a predetermined time. A pressure sensor installed in the purging line detects a pressure value V.sub.A0 in the atmospheric condition. A control unit of the leak diagnosis system determines a leak decision value V.sub.P0 on the basis of the atmospheric pressure detection value and an equation V.sub.P0 =V.sub.A0 +.DELTA.V.sub.0 where .DELTA.V.sub.0 is a difference between the output value in the predetermined positive pressure P.sub.0 and the output value V.sub.A0 in the atmospheric pressure condition and is constant. Therefore, it becomes possible to accurately execute the leak diagnosis.

Abstract: An internal combustion engine system includes a plurality of pneumatic elements including pneumatic resistances, pneumatic capacitances, and pneumatic sources. A pneumatic state model determines a pressure rate of change and pressure for certain areas of the internal combustion engine system designated as pneumatic volume nodes. Intake port flow is determined from pressures at the intake and exhaust manifolds, engine RPM and density correction factors. Intake port flow in a variable valve timing engine system further includes a phase deviation of the valve timing in the determination thereof.

Abstract: An apparatus for indicating the extent to which an air filter in an internal combustion engine is fouled. For this purpose the apparatus includes a pressure sensor, a sensor to detect the rotational speed of the engine, and an additional sensor which determines the load state of the engine. The signals of the three sensors are combined and serve to produce an air filter dirtiness indicating signal.

Abstract: Disclosed is a method for monitoring the status of a motor vehicle engine cooling system including sensing the pressure and temperature of coolant in the cooling system, generating respective output signals, and processing the output signals to generate an indication of a coolant system fault condition when the pressure of the coolant falls below a preset limit in relation to the temperature of the coolant. Apparatus for performing the method is also disclosed. Several embodiments are disclosed for indicating a coolant system fault condition, such as adjacent gauges for visual comparison, summing of the signals to provide a combined output signal of temperature modified by pressure for display on a gauge, and/or comparing the signals to trigger a warning signal when the preset limit is exceeded.

Abstract: An apparatus for collecting data related to the internal pressure of a fuel tank in a motor vehicle includes an analog pressure transducer that outputs a signal to charge a capacitor to a level proportional to the pressure in the fuel tank of the vehicle. A programmable microprocessor signals a gate to open a communication path between the capacitor and a discharge resistor, then monitors the number of clock counts that occur before the voltage across the discharge resistor drops below a reference voltage. The microprocessor uses the clock count to determine the absolute pressure within the fuel tank and transmits it to a central vehicle computer via a multiplexed data bus system.

Abstract: A vehicle warning system for warning a vehicle operator of a dangerous condition resulting from an abnormal engine parameter for use in a vehicle having a sensor for measuring the engine parameter and a gauge connected to the sensor by a line. The vehicle warning system includes an input port, a connector for connecting the input port to the line connecting the sensor and the gauge, a voltage detector for detecting when a voltage level at the input port exceeds a threshold level, and an alarm generator for warning an operator of a dangerous condition when the voltage detector detects that the voltage level exceeds the threshold level.

Abstract: A monitoring and safety system for air-operated parking brakes and foot brakes on a vehicle employs electric contacts to provide alarms when movement of the actuators occurs in a manner indicative of failure or malfunction in the actuators or in the brakes themselves. The system also includes a number of air pressure sensors for monitoring and alarm functions. In addition, parking brake air pressure is monitored for purpose of overriding a movement sensor alarm when air pressure in the actuator indicates that the vehicle is parked.

Abstract: A method for detecting trouble in a fluid pressure system which has a fluid pressure source including a fluid pump, a pressure tank connected to the pump, a pressure detector for detecting fluid pressure in the pressure tank, and a control device for controlling the operation of the fluid pump on the basis of an output signal from the pressure detector, comprising the steps of operating such fluid pressure systems with output fluid pressure from the fluid pressure source, detecting variation in the output signal from the pressure detector and when the output signal is less than a first predetermined value during operation of the fluid pressure system driving said fluid pump regardless of the output signal from the pressure detector, and when the variation in output signal from the pressure detector is less than a second predetermined value as a result of such driving of said fluid pump energizing a signal to indicate that the system is out of order.

Abstract: A fuel-flow alarm includes a fuel-flow detector for detecting the volume of fuel flowing in a conduit connecting a fuel tank to an engine fuel supply device and provides a warning when the volume of fuel is either above or below predetermined limits. The fuel-flow alarm includes a setting unit used to pre-set fuel-flow limit values for various operational states of the engine, detectors which detect the operational status of the engine, a compensation unit for adjusting the pre-set fuel flow limit values in dependence upon the operational status of the engine and a comparator which compares the limit values outputted from the compensation unit with the actual, detected flow rate. When a determination is made that the fuel flow rate exceeds at least one permissible limit value, the alarm is activated.

Abstract: An oil pressure alarm device for a motor vehicle comprises, an oil pressure switch, the oil pressure switch being activated to a conductive state when the circulation oil pressure of engine oil decreases below a predetermined level, alarm device for forming first current path in response to a conductive and non-conductive operation of the oil pressure switch after main power switch is turned on, condition detecting device for producing a detection signal in response to rotation of the engine, delay device for producing an enabling signal after a predetermined time of period has elapsed from when the detection signal is supplied from the condition detecting device, and alarm control device for forming second current path for the alarm device when the oil pressure switch is turned on under the condition that the enabling signal is outputted by the delay device, and for maintaining the second current path while the enabling signal is supplied from the delay device to the warning control circuit.

Abstract: An oil-pressure warning apparatus for automobiles includes an oil-pressure switch which is turned on when the circulation pressure of engine oil drops below a predetermined level, an alarm circuit which provides an electrical path in response to the on-off operation of the oil-pressure switch, and a warning control circuit which energizes the alarm circuit when the oil-pressure switch is turned on and maintains the energization of the alarm circuit. Thus, even when the oil pressure switch fluctuates back and forth between its on and off positions, the warning lamp will not flash.

Abstract: A starter-powered interlock switch means is provided for disabling a low oil pressure switch in power-driven apparatus such as lawn mowers, pumps, generators, tractors and the like. The interlock switch means disables the low oil pressure switch when the engine is not running to permit the engine to be easily started. Several embodiments of the interlock switch means are disclosed. The embodiments include a capacitor that is charged by the starter motor during cranking of the engine, and a relay switch that interrupts the circuit between the ignition primary and the low oil pressure switch to disable the low oil pressure switch. When the engine has started, the capacitor discharges to control one or more other switches that in turn close the circuit between the ignition primary and the low oil pressure switch. The closing of the latter circuit enables the low oil pressure switch to be activated when a low oil pressure condition is sensed.

Abstract: Method and system for detecting a level of an engine oil of an engine include an operation for detecting a time duration in which the engine is operating. When the engine operation has continued for more than a predetermined time period, and the engine is stopped subsequently, the oil level is detected after the elapse of a second predetermined time period in which the engine is stopped. By this feature, the engine oil level is detected very accurately.

Abstract: A closed-loop control for sensing the completion of popcorn popping in a microwave oven and automatically shutting down the oven. A sensor is acoustically coupled to the microwave oven cavity and provides an electrical signal to an amplifier and filter. The amplified and filtered signal is processed by a pop detector which includes an integrator and shut-down command generator responsive to a decreasing rate of popping to shut the oven off. The integrator provides a pre-pop timer function to maintain the oven on until popping commences. In an alternative embodiment, the peak rate of popping is detected and held and the oven is shut off when the popping rate falls to a predetermined ratio of the peak rate or a predetermined time elapses after the peak rate is detected, whichever first occurs.

Abstract: Off-highway trucks generally rely on a suspension system which employs a plurality of gas-over-liquid type struts. These struts are critical to proper operation of the vehicle such that a single collapsed strut can have serious manifestations in structural damage, tire wear, and payload monitor accuracy. These consequences can be mitigated by an accurate and reliable strut monitor. Pressure type sensors are disposed on each of the struts and their pressure is monitored during three critical phases of operation. These phases include static, loading, and roading modes and each mode requires a distinct method for detecting a collapsing strut. The presence of a collapsing strut, detected by any of the three methods, is communicated to the vehicle operator whereby operation can be immediately suspended. The system avoids the serious consequences of vehicle operation with a collapsed strut by providing the operator with immediate and positive feedback on the condition of the struts.

Abstract: A brake condition warning system for liquid cooled brakes that includes an indicator showing whether pressure in the cooling liquid passing through the erodable brake members has exceeded an acceptable valve which corresponds to an excessive amount of brake wear. Also, there may be included temperature sensitive means for sensing the temperature of the liquid in the chamber preventing the pressure indication until the cooling liquid has reached a predetermined operating temperature thus preventing false indications of excessive wear due to the viscosity of cold cooling liquid.

Abstract: An electronic oil pressure transducer circuit interfaces a piezoresistive pressure sensor to magnetic needle movement and lamp or electronic instrument control computer for reliable automotive engine oil pressure instrumentation. Circuit design uses standard components suited for automotive under-hood environment. Calibration is performed at the design level, eliminating the need for expensive on-line procedures. Circuit assembly is designed for automated, high-volume production.