Matches 1 - 16 out of 16
Match Document Document Title
7535351 Acoustic intrusion detection system  
An active acoustic intrusion detection system includes a pair of dipole emitters (180 degrees out of phase with each other) which emit an audible frequency f (preferably 1 KHz) and a pair of...
7338398 Continuously variable transmission or clutch with ortho-planar compliant mechanism  
A continuously variable transmission or clutch device ( 10 ) includes at least one pulley ( 18 ) rotatable on a pivot ( 28 ) and having a pair of adjustable sheaves ( 30, 34 ) including a movable...
5734626 Synchronisation device comprising a time zone detector  
The invention concerns a synchronisation device for synchronising the analogue display with the digital display of a timepiece. The device includes a contact wheel (1), driven by the hour-wheel of...
5555222 Low distortion geophone spring  
An improved reduced distortion spring spider for geophones is disclosed that has the desired ratio of spurious resonant frequency to the natural frequency of the geophone and can absorb the sharp...
5450375 Geophone shock absorber  
A geophone is disclosed that has a cylindrical housing closed at one end by a bottom and the other end by a top. A magnet assembly with pole pieces at each end of the magnet is centrally mounted in...
5134593 Geophone spring  
A spring for a seismometer for suspending one body relative to a fixed reference point within a housing including an outer ring and an inner ring interconnected by a plurality of arcuate legs. Each...
5134594 Geophone spring  
An improved spring spider for geophones is disclosed that has the desired ratio of spurious resonant frequency to the natural frequency of the geophone and can absorb the sharp lateral forces...
4685094 Lateral compliance device for geophone springs  
A spring system for use with a geophone for suspending a reference mass axially and laterally. One spring of the spring system flexes more axially than laterally, and the other spring of the spring...
4623991 Delta-shaped geophone spring  
For use in geophones to support either the coil or the permanent magnet, a spring formed from a disc, said spring having an outer ring, an inner ring, and three legs connecting the outer and inner...
4504932 Geophone having a non-conductive coilform  
A geophone having a non-conductive coilform thereby avoiding the disadvantages of conductive coilform damping and allowing closer control of both sensitivity and damping solely through shunt...
4458344 Tapered geophone spring  
A geophone spring is disclosed in which an inner ring member and an outer ring member are connected by a plurality of leg members. Each leg member includes a tapered segment that is wider at its...
4412317 Transducer for picking up mechanical vibrations, in particular seismic waves, and a seismic measuring system including such a transducer  
Transducer for converting mechanical vibrations into corresponding electrical signals. Two separate coils are disposed in permanent magnetic fields produced by a magnet assembly. The coils on the...
4323994 Geophone spring  
A new geophone spring is disclosed wherein the outer and inner rings of the spring are connected by leg members having a substantially straight segment which will pivot about an outer portion of...
4285054 Geophone  
A geophone comprising an annular coil-mass and a permanent magnet assembly positioned inside the annular coil-mass with their longitudinal axes generally coinciding to place the coil-mass in the...
3878504 Damped geophone  
A damped geophone which includes a closed housing wherein a magnet supported between a pair of pole pieces is axially supported on an upstanding post connected with a bottom closure member and...
2788511 Lightweight seismometer  
Matches 1 - 16 out of 16