SU808935A1 - Device for measuring instantaneous velocitu of shaft rotation - Google Patents

Description

The invention relates to a measuring technique and can be used in automatic devices in instrument making, machine tool building, mechanical engineering, when measuring the instantaneous speeds of rotating shafts that have a rigid mechanical connection with a pulse speed sensor. A device for measuring the speed of rotation is known, which contains a speed sensor, a reference frequency generator, a key, a reference frequency counter, a sensor pulse counter, a decoder, a register, and a comparator. 11 Such a device cannot measure speed during one period between speed sensor pulses, t. e. instantaneous speed It is also known a device for measuring the rotational speed of a shaft, which contains a pulse speed sensor, a reference frequency generator, a key, one input of which is connected to a speed sensor, another is connected to a reference frequency generator, a reference frequency pulse counter (hereinafter just a counter ) and additional counters and a decoder included in the block select the number of periods of the pulse of sensor 2. The purpose of the invention is to increase the accuracy of measurement of the instantaneous velocity and its deviation. The goal is achieved by introducing an additional decoder, an additional key and an oscilloscope into the device, with the reference frequency generator connected to the counting input of the reference frequency pulse counter, the set input to which is connected to the output of the key, and the output through the decoder to the second key input, the first input of the oscilloscope and the first input of the additional. a key whose output is connected to the installation input to zero of an additional counter, the counting input of which is connected to the reference frequency generator, and the output via an additional decoder with the second input of the additional key and the third input of the oscilloscope, the second input of which is connected to the output of the pulse speed sensor .. ya FIG. 1 is shown (Lsema device; Fig. 2 - graphs of its principle of operation. The device contains a generator 1 reference frequency, a counter 2 pulses, a decoder 3, a pulse sensor 4 speeds, a key 5, a time interval 6 before the interval is added, consisting of additional counter 7 decoder 8 and key 9, and oscilloscope 10 The generator 1 of the reference frequency is connected to the counting inputs of counter 2 and an additional counter 7. The output of the counter is connected to the decoder 3, the output of which is connected to one input of the key 5. The second input of the key 5 is connected to the output of the pulse sensor speed 4. The output of the key 5 is connected to the output of the installation of counter 2 to zero. The output of the additional counter 7 is connected to the additional decoder 8, the output of which is connected to one input of the additional key 9. The second input of the additional key 9 is connected to the output of the decoder 3. The output to. Achocha 9 is connected to the input of the installation of the additional counter 7 to zero. The output of the decoder 3 is connected to the input of the waiting sweep (the first input of the oscilloscope), the output of the pulse sensor

4- to the amplifier input (second input), and the output of the additional decoder 8 - to the oscilloscope modulator 10 (third input).

The device works as follows.

In the initial state, the counter 2 and the additional counter 7 are in the zero state, the key 5 and the additional key 8 are in the forbidden state. When pulses are received from the pulse speed sensor 4 (Fig. 2, plot A) to one key input

5, the latter is unlocked and permits the arrival of pulses from the generator 1 of the reference frequency to counter 2 (Fig. 2, plot B). The counter 2 and the decoder 3 generate pulses delayed by the speed sensor pulses by magnitude (Fig. 2, plot rj. The delay time is chosen so that it does not exceed the period between the pulses of the speed sensor corresponding to the maximum allowable speed of rotation of the shaft. Delayed pulse ( Fig. 2, plot D) on the second input locks the key 5, which resets the counter 2 to the zero state. At the same time, the delayed pulse triggers the oscilloscope waiting for scanning and the unlock device of the unlocking device are additional key 9

(Fig. 2, plot D), Key 9 permits the arrival of pulses of the reference frequency to the additional counter 7. The additional counter 7 and the decoder 8 form the time difference of the increment Td | - | (.c, at the end of which an impulse is formed (Fig 2, plot E). The magnitude of the time interval of the increment Tdosm BL iorpaeTCH such that the sum of the intervals of the delay time T AMB and the increment Tdgki (Tu - +

+ Tsetch.} Corresponds to the period between the pulses of the speed sensor at the nominal speed of rotation of the shaft. The pulses from the block 6 of the interval of time (Fig. 2, plot E) arrive at the input of the oscilloscope modulator 10, highlighting a point on its screen, the time reference of which relative to the start of the sweep (relative to the pulses of plot d) corresponds to the nominal shaft rotation speed . The pulses of the pulse. Sensor 4 speeds (Fig. 2, plot A) are fed to the input of the amplifier of the oscilloscope 10.

Thus, on the oscilloscope screen, each pulse of the speed sensor, whose temporal position relative to the light point will uniquely correspond to the deviation of the momentum speed of the enemy shaft relative to the nominal, will be viewed.

Shaping the delay interval, after which an oscilloscope sweep start pulse appears, makes it possible to exclude a significant portion of the period between the pulses of the speed sensor from viewing on the screen of the oscilloscope. This makes it possible to increase the oscilloscope scanning speed and thereby increase the measurement accuracy of the instantaneous rotational speed of the shaft.

Claims (1)

Invention Formula A device for measuring the instantaneous speed of rotation of the shaft, containing a pulse speed sensor, the output of which is connected to the first key input, a reference frequency generator, a pulse frequency counter of the reference frequency, the output of which is connected to the decoder input, and an additional A pulse counter, characterized in that, in order to increase the measurement accuracy of the instantaneous velocity and its deviation, an additional decoder is introduced into the device. additional key and oscilloscope. the reference frequency generator is connected to the counting input of the pulse counter of the reference frequency, the installation input of which is connected to the output of the key, and the output through the decoder with the second input of the switch, the first input of the oscilloscope and the first input of the additional switch, the output of which is connected to the installation input to zero additional About a counter whose counting input connected to the generator of the reference frequency, and the output through an additional decoder with the second input of the additional key and the third input of the oscilloscope, the second input that connects to the output of the pulse speed sensor. Sources of information taken in attention during examination certificate of the USSR 01 P 3/54, 1976. certificate of the USSR 01 R 3/54, 1973