1981-09-11
1986-01-28
Freeh, William L.
Pumps
Miscellaneous
73807, 73825, 417415, 417 18, F04B 4906, F04B 4908, F04B 3504, G01N 310
Patent
active
045668680
ABSTRACT:
A liquid pressure source, e.g. for use in soil mechanics laboratories, has a piston-cylinder unit driven by a stepper motor: a pressure transducer indicates the liquid pressure and a digital feedback control unit responds to generate stepping pulses to maintain a desired pressure. A step counter can be included to provide an accurate indication of volume change, and backlash compensation may be provided by arranging that the counter, following a direction change, ignores motor steps until a pressure change occurs.
REFERENCES:
patent: 3199341 (1965-08-01), Heuer, Jr. et al.
patent: 3666141 (1972-05-01), Ma et al.
patent: 3847507 (1974-11-01), Sakiyama
patent: 3882861 (1975-05-01), Kiettering
patent: 3915651 (1975-10-01), Nishi
patent: 3966358 (1976-06-01), Heimes
patent: 4076458 (1978-02-01), Jones
patent: 4137913 (1979-02-01), Georgi
patent: 4209258 (1980-06-01), Oakes
patent: 4259038 (1981-03-01), Jorgensen
patent: 4299541 (1981-11-01), Ohara
patent: 4313075 (1982-01-01), Stewart
patent: 4321014 (1982-03-01), Eborn
patent: 4326837 (1982-04-01), Gilson
patent: 4331262 (1982-05-01), Snyder
patent: 4336000 (1982-01-01), Jorgenson
patent: 4339699 (1982-07-01), de Jones
patent: 4396385 (1983-08-01), Kelly
patent: 4397610 (1983-08-01), Krohn
Freeh William L.
Gammons Robert T.
Geotechnical Digital Systems Limited
LandOfFree
Pressure source does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Pressure source, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Pressure source will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1304313