Eaton Corporation

Paul G Rops

James E Hansen

Richard Walter Hirthe

Ruth E Hubbell

Scott A Reid

Mark H Polczynski

Erich Rehm

Martin Arthur Seitz

Steven R Schachameyer

Lian Q Zou

Peter J McGinnis

Francis Christopher Edrozo

Robert A Bauer

A plug for insertion through the wall of a vessel filled with fluid to be monitored has an extension immersed in the fluid which has a pair of wire electrodes helically wound thereon in spaced arrangement. The electrodes are wound at a uniform pitch in one embodiment and wound with regions of closely and widely spaced pitches in another embodiment. In a third embodiment, the electrodes are helically wound in spaced parallel arrangement at a pitch greater than the spacing of the pair. A thermistor is disposed on the extension for providing a fluid temperature signal. The electrodes are excited sequentially by a low voltage at a fractional Hertz (low) frequency and a (high) frequency of at least one Hertz and the current and temperature are measured. The impedance and differential impedance are computed from the measured currents. From stored values of the differential impedance as a function of temperature for various known fluid conditions, the condition of the fluid is determined; and, if greater than a predetermined threshold, an alarm is activated and/or the fluid condition displayed.

Monitoring fluid condition with a spiral electrode configuration

A method for real time monitoring fluid in a vessel with a probe having a pair of electrodes immersed in the fluid. The disclosed probe has the electrodes arranged helically on a rod, sized and configured for insertion in an engine dipstick hole. Preferably, the probe has spiral electrode winding up regions different pitch to provide improved impedance response at low fractional Hertz and high (at least one Hertz) frequencies of excitation. In one version with alternating voltage the difference in current magnitude measured at the low and high frequencies is compared with stored known values for known fluid conditions and an electrical signal indicative of fluid condition is generated. Examples with engine drain oil and heavy duty transmission lubricant fluid are presented. The impedance properties measured can determine the percentage remaining useful life (RUL) of the fluid. In another version of the method the current phase shift angle is measured at the fractional Hertzian frequency; and, from known values of current phase shift angle of the fluid, at various conditions, the condition of the fluid determined. The differential current measured and the measured phase shift angle may be combined, for example, by the square of the sum of the squares procedure to provide an enhanced impedance change indicator.

Monitoring fluid condition through an aperture

A control circuit is provided for transferring power and communication signals through a wireless coupling device in a vehicle steering column. The device can comprise a rotary transformer having a primary and secondary magnetic structure respectfully associated with the wheel side and column side of the steering column. A squib power circuit transforms a high energy power signal suitable for firing an air bag from the column side to the wheel side. A low energy power circuit generates a signal from the column side to the wheel side suitable for operating isolated wheel side electronics, such as cruise control and the like. A tone encoder and decoder circuit communicates low level control signals suitable for signalling wheel side commands from the wheel side to the column side. The low energy power circuit and the tone encoder circuit operate simultaneously and continuously without signal debilitating interaction.

Vehicle steering column control system

A Hall-Effect position sensing system is provided that is particularly advantageous for use in vehicular applications such as for sensing position of a transmission gear change shift rail by requiring only a single power conductor (34) between a Hall-Effect switch device (90) and a remote power source (20) such as a battery by connecting a signal output terminal (16) of device (90) to conductor (34) in close proximity to device (90) and including a drop resistor (r.sub.1) such that a micro-processor (24) is able to provide an output control signal (32) indicative of position by monitoring the effect of the output signal of device (R) on conductor (34).

Hall-Effect position sensing system and device

Growing community of inventors

Germantown, WI, United States of America

Paul G Rops