Electricity: measuring and testing – Impedance – admittance or other quantities representative of... – Lumped type parameters
Patent
1995-08-31
1997-07-08
Wieder, Kenneth A.
Electricity: measuring and testing
Impedance, admittance or other quantities representative of...
Lumped type parameters
324676, 73 5301, 73 5305, 73 5307, 7386108, G01N 2722, G01N 1102, G01N 1504, G01F 156
Patent
active
056465394
ABSTRACT:
An apparatus for sensing two parameters of a hydraulic system having a hydraulic line includes a pair of electrodes contained within the line and oppositely spaced, forming a capacitor. The apparatus alternately produces first and second charging currents having first and second constant magnitudes, respectively, and charges the capacitor to respective first and second predetermined voltages. The apparatus detects the time needed to charge to the first and second predetermined voltages and produces a pulse width modulated signal having a series of alternating first and second pulses. The first and second pulses are indicative of the first and second parameters, respectively. The first pulse is defined by the time required to charge the capacitor to the first predetermined voltage. The second pulse is defined by the time required to charge the capacitor to the second predetermined voltage. The apparatus determines the two parameters as a function of the pulse width modulated signal.
REFERENCES:
patent: 3595078 (1971-07-01), Beck et al.
patent: 3635082 (1972-01-01), Prellwitz et al.
patent: 3724474 (1973-04-01), DeVale
patent: 3802261 (1974-04-01), Zimmerman et al.
patent: 4074184 (1978-02-01), Dechene et al.
patent: 4240028 (1980-12-01), Davis, Jr.
patent: 4266188 (1981-05-01), Thompson
patent: 4468611 (1984-08-01), Tward
patent: 4604904 (1986-08-01), Massen
patent: 4646070 (1987-02-01), Yasuhara et al.
patent: 4658208 (1987-04-01), Lee et al.
patent: 4713603 (1987-12-01), Thorn
patent: 4714048 (1987-12-01), Jefferies et al.
patent: 4751842 (1988-06-01), Ekrann et al.
patent: 4853718 (1989-08-01), ElHatem et al.
patent: 4894604 (1990-01-01), Dowling et al.
patent: 4920795 (1990-05-01), Codazzi et al.
patent: 5262732 (1993-11-01), Dickert et al.
patent: 5274334 (1993-12-01), Mills
patent: 5347848 (1994-09-01), Schoeffel et al.
patent: 5382942 (1995-01-01), Raffa et al.
patent: 5461321 (1995-10-01), Sanders et al.
patent: 5540086 (1996-07-01), Park et al.
patent: 5554937 (1996-09-01), Sanders et al.
Saloka et al. SAE Technical Paper Series - 910497 Feb. 25-Mar. 1, 1991 "A Capacitive Oil Deterioration Sensor".
Codina George
Murr Donna J.
Ramamoorthy Chandrasekar
Brown Glenn W.
Caterpillar Inc.
Wieder Kenneth A.
Yee James R.
LandOfFree
Multi-purpose capacitive sensor does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Multi-purpose capacitive sensor, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Multi-purpose capacitive sensor will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2410684