DEVICE FOR MEASUREMENT OF GAS-AIR FLOW SPEED Russian patent published in 2010 - IPC G01P5/24 

FIELD: mining.

SUBSTANCE: invention may be used to detect average speed of gas-air flow along section of mine working. Device comprises excitation pulse shaper 3, piezoceramic converters 1 and 2, commutators 4 and 5, two channels of received signals processing, every of which comprises amplifier 10 (11), attenuator 12 (13) and received waveform envelope detector 14 (15), at the outlet of which the following circuits are connected in parallel - circuit of received signal 16 (17) capture and circuit of tracking 18 (19) of its position in specified range. Each circuit 16 (17) consists of counter 22 (23) with count control unit 24 (25) connected to clock pulse oscillator 8 of shaper 3, comparator 20 (21), detector of pulse capture 26 (27) and detector of phase difference sign 28 (29). Each tracking circuit 18 (19) includes doubled circuit of sampling - storage 30 (31), control keys of which are managed by signals of sampling pulses shaper 36 (37), differential amplifier 32 (33) and analyser of zero level 34 (35). Signals of counters 22 (23) and shaper 3 arrive into unit of time ranges measurement 6, including two channels - to measure difference of received signals arrival times and to measure time range of signal distribution from radiating to receiving converter and connected to computing block 6.

EFFECT: improved accuracy of flow speed measurement due to more accurate detection of received signal arrival moment.

2 cl, 2 dwg