Device for measuring the time of propagation of elastic waves in the array
(57) Abstract:The invention relates to mining equipment, and is intended to assess the stress-strain state of rocks and diagnostics of array. The goal is to improve the accuracy of measurement of elastic wave propagation in the array and extending functionality by measuring the damping of the waves. When the wave propagation in rock mass fires closest to the source sensor-breaker and disconnects the DC circuit. Then after a certain period of time, due to the speed of wave propagation, works far sensor-breaker and disconnects the DC circuit. When triggered, each sensor pulse occurs, respectively starting and stopping the first counter node, which is the measurement of the travel time of the waves between the two sensors-breakers. The attenuation of the wave is determined by the time intervals between the opening and re-closure of both sensors-breakers, which are fixed second and third counting nodes. 1 Il. The invention relates to mining and can be used for evaluating the stress-deformiroemosti to determine the time of propagation of elastic waves in rocks /1/, consisting of two sensors connected with the accounts node is configured to start and stop the account by the sensor signals.A disadvantage of the known device is the impossibility of measuring the amplitude of an acoustic wave and a significant error of measurement of propagation time of the waves in the array, due to the instability of the acoustic signal from the sensors.The purpose of the invention is to improve the accuracy of measurement of elastic wave propagation in the array and the assessment of their amplitude.This objective is achieved in that in the known device introduced two additional accounts of the node, and each sensor is made in the form of sensor-breaker in the circuit constant current ability to supply pulses to the corresponding additional counting site for the beginning and termination of the account by measuring the duration between the moments of opening and closing the DC circuit, proportional to the amplitude of the acoustic signal.In the known technical solution such distinctive features is not found, which makes the proposed solution with a significant difference.The drawing shows a block when its in the array of rocks 9, blocks DC circuits 3, 4, counting the nodes 5, 6, 7. The inputs of the amplifiers counting nodes 5 and 6 and 5 and 7 are interconnected. Sensors-breakers included in the DC circuit, connected to respective amplifiers counting nodes 5, 6, 7.The proposed device operates as follows.The elastic wave generated by pulse source 8 will extend through the array of rocks 9 and reaching the sensor-breaker 1, will break the circuit constant current, resulting in an excitatory pulse AC, which is stable in amplitude and frequency. This momentum will be counting amplifier node 5, which will start the pulse count. Then after a certain period of time due to the propagation velocity of elastic waves, wave reaches the transducer-breaker 2 and opens the second DC circuit, which includes the sensor-breaker 2, there will be a pulse AC, also stable in frequency and amplitude, which goes to the input of the second amplifier in the counting node 5, and the pulse count in the counting node 5 will be on the scoreboard counting node locks the transit time of the waves from the sensor-breaker 1 to sensor-breaker 2.Similarly operates and the second channel with sensor-circuit breaker 2. Time of opening and closing the DC circuit sensor-circuit breaker 2 is fixed on a digital display counting node 7.Knowledge of the amplitude of the wave at different bases sounding allows to determine the ratio and logarithmic decrement of damping of waves by known formulas.Sources of information
Properties of rocks under different types and modes of loading, as amended Beron, A. I., Izd-vo "Nedra", 1983, S. 182 - 186. Device for measuring the time of propagation of elastic waves in the array that contains two sensor connected with the accounts node vypolnennyh countable units, as each sensor is made in the form of sensor-breaker in the circuit constant current ability to supply pulses to the corresponding additional counting site for the beginning and termination of the account by measuring the duration between the moments of opening and closing the DC circuit, proportional to the amplitude of the acoustic signal.
FIELD: optical engineering.
SUBSTANCE: method can be used for optical images received from holograms. According to the method, two-exposition object hologram is made by sin out-of-axis scheme. Interfering wave fields are restored from hologram by strong coherent radiation received from tested object. Interference pattern is registered at the direction of initial reference beam.
EFFECT: simplified process of finding deformations of objects.
FIELD: measuring technique.
SUBSTANCE: when measuring air-tightness of close jars made of dielectric material, measurement of resonant frequency and frequency of beating of frequency-modulated oscillations is used followed by analytical conversion of mentioned characteristics which have information on air-tightness of closed jars.
EFFECT: reduced error of measurement.
FIELD: machine building.
SUBSTANCE: device comprises a force-measuring machine and a reference dynamometer fixed to measure tension in grips of the specified machine, and to measure compression - installed on a roller support of this machine. According to the invention it comprises a bar code rack rigidly fixed with the help of a metal bracket on a movable cross beam of the force-measuring machine and a highly accurate digital level installed at the distance of at least 2 metres from the force-measuring machine.
EFFECT: higher accuracy and validity of measurement results, expansion of the field of application, higher convenience in performance of measurements.
FIELD: electric engineering.
SUBSTANCE: device has stable frequency generator, counter and indicator. Launch signal to start input of counter is sent through galvanic device, inverter and operation mode switch. Counting stop signal is sent to stop input of counter through another inverter and operation mode switch.
EFFECT: higher efficiency.
FIELD: electric engineering.
SUBSTANCE: device has support generator, forming means, distributor, main counter and three measuring channels. Each measuring channel includes OR circuit, nonius generator, nonius counter, main and additional buffer registers. Two channels operate simultaneously in device: one measures time intervals between input pulses, and on basis of measurements of second one calibration of this couple of channels is performed. During calibration signal concurrently is sent to inputs for launching and stopping nonius generator in channel, performing calibration, and from same signal nonius generator is launched in channel, performing working measurements.
EFFECT: higher precision.
FIELD: measurement technology.
SUBSTANCE: second register is introduced into the meter additionally which register has data inputs connected with corresponding outputs of multiphase pulse oscillator. Outputs of the second register are connected with corresponding inputs of second coder and clock-pulse input of the register is connected with input signal terminal of the beginning of time interval to be measured. Meter also has third and fourth registers, flip-flop and inverter unit. First input of second register and outputs of second coder are connected with corresponding junior digital inputs of adder through inverter unit. Senior digital inputs of adder and its transition input are connected with logic "unit" bus. Senior digital inputs of adder are connected with corresponding outputs of the third register which has data inputs connected with corresponding outputs of pulse counter. Inverting input of pulse counter is connected with first input of multiphase pulse oscillator.
EFFECT: improved speed of operation; improved precision of measurement.
FIELD: measuring equipment, possible use in multi-channeled transformers with greater number of recorded time intervals in experimental physics and radiolocation.
SUBSTANCE: in accordance to method, a series of clock impulses is generated, input signals are processed on n-channels. Input signals are recorded. After receipt of input signals they are compared to input signals on previous clock impulse. In case of their difference, changed input signals and time of change of input signals are recorded. In proposed solution rational usage of memory of recording device is provided as well as increase of dynamic range of registered time intervals because constant input signals are recorded into memory no longer and recording is continued if input signals change.
EFFECT: expanded functional capabilities.
2 cl, 2 dwg
FIELD: devices for measuring time intervals, possible use for measuring radio impulses delay time.
SUBSTANCE: claimed device for measuring time intervals contains generator of impulses, high frequency generator, object, during passage through which the radio-impulse generated by high frequency generator is weakened, amplifier and oscillograph, while first output of impulse generator is connected through high frequency generator to input of object, during passage through which the radio-impulse generated by high frequency generator is weakened, second output of impulse generator is connected to first input of oscillograph, output of object, during passage through which the radio-impulse generated by high frequency generator is weakened, through the amplifier is connected to second input of oscillograph. The oscillograph included in composition of claimed device may be made in single-channel or double-channel form.
EFFECT: expanded arsenal of technical means serving aforementioned purpose.
3 cl, 1 dwg
FIELD: physics; radio.
SUBSTANCE: time-interval metre is designed for taking frequency and time measurements in radio measuring devices. The time-interval metre comprises series-connected reference generator (1) and a cyclic pulse counter (2), N request channels, each of which includes memory units (31-32) with outputs combined and connected to the corresponding input of an information processing device (4), a unit for generating and fixing reference frequencies (5), series-connected switch (6), with number of outputs equal to number of request channels N, and a control unit (7), two pulse counters (81-82) and a control trigger (9) in each of the N request channels, and a unit for stopping counting and preliminary set up of a decade (10). In the version of the device there is a channel for measuring time-interval, duration and period (11). The control unit (7) is made with auxiliary (N+1) and (N+2) outputs, and the information processing device (4) with an auxiliary (N+1) (information) input. The device is essentially made in form of a single complex-functional block on a large integrated circuit of the K1897AIT type.
EFFECT: reduced measurement errors, faster information output, possibility of measuring single (random) intervals, duration and period of recurrent pulses with averaging.
2 cl, 4 dwg
SUBSTANCE: recirculation time-code converter comprises multi drop delay line, pulse counter, memory register, D-trigger, element OR-NO, pulse generator, n excluding OR elements and encoder.
EFFECT: higher accuracy of conversion.
SUBSTANCE: alternating odd and even separate measurement intervals with duration equal to Tx+τx and Tx-τx, where Tx is the period of the input signal, τx is the duration of the input signal, are formed. Quantising pulses with repetition period T0 during n measurement intervals Tx are counted. The averaged value of duration of the input time interval over the overall measurement interval is determined using the formula: where n is the even number of periods of the input signal in the overall measurement interval; T0 is the repetition period of the counted pulses; N2j-i and N2j denote the number of quantizing pulses in the j-th odd and even separate measurement interval, respectively.
EFFECT: wider range for measuring duration of time intervals while increasing measurement accuracy and simplifying hardware implementation.