Electrical generator or motor structure – Non-dynamoelectric – Piezoelectric elements and devices
Patent
1994-06-14
1995-02-07
Dougherty, Thomas M.
Electrical generator or motor structure
Non-dynamoelectric
Piezoelectric elements and devices
310316, 333151, 333194, H03H 9145
Patent
active
053878337
ABSTRACT:
A method and apparatus in which signal output of an acoustic wave device is separated into desired and undesired components. An excitation signal to an input of the acoustic wave device is periodically interrupted for durations based upon the time required for acoustic waves to travel from the input to the output of the device. The duration of excitation is less than the time required for wave travel, allowing electromagnetic interference to complete its passage to the output before the arrival of acoustic wave energy. The non-simultaneous arrival of electromagnetic interference and acoustic wave-generated energy allows the electromagnetic interference to be gated from the output. Electrical switches are employed, such as double-balanced mixers or PIN diode switches. The period of pulses for providing the interruptions of excitation is at least as great as the sum of the required time for acoustic wave travel and the time during which the device is excited. The switch for gating the output remains open during intervals in which the device is excited.
REFERENCES:
patent: 3551837 (1970-12-01), Speiser et al.
patent: 3845418 (1974-10-01), Weglein
patent: 3855556 (1974-12-01), Hartmann
patent: 4078210 (1978-03-01), Lewis
patent: 4221132 (1980-09-01), Poole
patent: 4247903 (1981-01-01), Grudkowski et al.
patent: 4333342 (1982-06-01), Gilden et al.
patent: 4939387 (1990-07-01), Popek et al.
patent: 5076094 (1991-12-01), Frye et al.
patent: 5111168 (1992-05-01), Panasik et al.
patent: 5130257 (1992-07-01), Baer et al.
patent: 5221871 (1993-06-01), Fuchs et al.
Martin, S. J. et al., "Characterization of SH Acoustic Plate Mode Liquid Sensors," Sensors and Actuators, 20 (1989), pp. 253-268.
M. Hoummady et al. "Acoustic Wave Viscometer", 1991, vol. 62 (8), pp. 1999-2003, Rev. Sci. Instrum.
Akihiro Sawaguchi et al. "Liquid Viscosity Measurement Using SH Wave Propagation . . . ", 1992, vol. 31 (9B), pp. 3094-3097, Jpn. J. Appl. Phys.
U. Kaatze et al. "Acoustical Absorption Spectroscopy of Liquids between 0.15 and 3000 MHz . . . ", 1988, vol. 21 (4), pp. 402-406, J. of Phys. E. Sci. Instrum.
Dougherty Thomas M.
Hewlett--Packard Company
LandOfFree
Method and device for separating acoustic wave-generated energy does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and device for separating acoustic wave-generated energy , we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and device for separating acoustic wave-generated energy will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1112632