SU966595A1 - Device for monitoring electric motor rotational speed - Google Patents

Description

one

The invention relates to automation and can be used to control the speed of rotation of a shaft, in particular a micromotor shaft equipped with a tachometer.

A device for controlling the rotational speed is known, which contains series-connected circuits for generating pulses, the number of which is proportional to the measured number of revolutions, differentiating and integrating circuits and triggers. Schmitt with different levels of operation and with separate load P J.

It is also known a device for controlling the speed of rotation of an electric motor shaft, comprising a tachometer mounted on an electric motor shaft, a calibrated divider, a threshold element, a differentiating circuit, a time delay circuit, and an alarm and shutdown unit whose output is connected to the input of an E2J motor.

However, these devices have a low control accuracy (due to the presence of an intermediate amplitude-frequency signal to analog transducer), inertia response and a limited range of controlled speeds (due to fQ using smoothing capacitors), as well as limited functionality, in particular , the inability to control the motion parameters of objects having 15 at the output of an aperiodic pulse sequence.

The purpose of the invention is to improve the accuracy of control and speed while expanding the range of controlled 20 speeds and functionality.

Claims (2)

The goal is achieved by the fact that the device is equipped with a limited amplitude at the bottom, two coincidence circuits with a BAN system, a single vibrator and an additional threshold element, and a calibrated divider is equipped with an additional output that through the first coincidence circuit, an additional threshold element and a differentiating circuit are connected to the enable input of the BREAK scheme, and os. the calibrated divider's output through the second coincidence circuit, the threshold element and the one-shot are connected to the inhibit input c; the BANE output, the output of which is connected, to the input of the alarm unit. and the second output of which is connected to the second inputs of the coincidence circuit the output of the tachometer through the amplitude limiter from the bottom is connected to the input of the calibrated object tel. Figure 1 shows the structural diagram of the device; Fig.2 time diagrams of channels about, processing information. The device for controlling the speed of rotation of the motor shaft contains a tachometer 1, which through an amplitude limiter from below 2 is connected to the input of a calibrated divider 3, equipped with two outputs connected to the inputs of the coincidence circuits k and 5 - The output of the first coincidence circuit C through an additional threshold element 6 and differentiates A common circuit 7 is connected to a permissive input of the BAN 8 circuit, and the output of a coincidence circuit 5 through a threshold element 9 and a one-shot 10 with a locking input of the BAN circuit. The output of the BAN 8 circuit is connected to the input of the shutdown and signaling circuit 11, one output of which is connected to the second inputs of the coincidence circuit t and 5 via the time delay circuit 12 and the second output is connected to the input of the electric motor 13. The device operates as follows. The signal i amplitude of which is proportional to the parameter being measured, in particular, the angular velocity of rotation of the shaft of the electric motor 13, from the output of the tachometer 1 through the amplitude limiter from below 2 is fed to the input of the calibrated divider 3. From the first 1 output of the calibrated divider 3, the signal x is removed, level 4 of exceeds the level of the U4 signal taken from the second output. At the time of the start of the electric motor 13 from the shutdown and signaling unit, a time delay circuit 12 is activated, the output pulse of which blocks the passage of signals x, y and the outputs of the coincidence circuits k and 5 for the time of engine acceleration. When the speed of the engine depressing 13 decreases to a level equal to the limit value, the voltage y, at the input of the threshold element 9 will fall below the threshold of its operation, and the pulses y, y, respectively, at the output of the threshold element and the one-shot 10 stop. At the same time, from the first output of the calibrated divider 3, the signal x through the coincidence circuit, the threshold element 6 (X2) and the differentiating circuit 7 (x) will be fed to the enable input of the BANE 8 circuit and pass to its output in connection with the absence of a blocking signal at the prohibitory entrance. From the timing diagram of FIG. 2), it can be seen that the pulses y, over time, overlap the pulses of positive polarity x t, and as the shaft rotates at a lower speed, they first of all disappear, thereby providing the signal to the input of the shutdown and signaling unit. The use of new elements: coincidence circuits, a BREAK scheme, a single vibrator, a threshold element and a calibrated divider with an additional output, the signal of which exceeds the amplitude of the signal taken from the main output, allows you to process information without intermediate conversion to analog value. As a result, an intermediate converter with an inertial element - a storage capacitor is eliminated, which increases the device performance, control accuracy, expands the range of controlled speeds and functionality. Apparatus of the Invention A device for monitoring the rotational speed of an electric motor shaft, comprising a tachometer mounted on an electric motor shaft, a calibrated divider, a threshold element. a differentiating circuit, a time delay circuit, and an alarm and trip unit, the output of which is connected to the input of an electric motor, characterized in that, in order to increase the control accuracy and speed when extending the range of controlled speeds, it is equipped with an amplitude limiter from below, two coincidence circuits, a BAN circuit, a single vibrator and an additional threshold element, and the calibrated divider is provided with an additional output, which through the first matching circuit, an additional threshold element and diff rentsiruyuschuyu circuit is connected to the inverted enable input circuit and the main output of the calibrated divider through the second coincidence circuit, the threshold element and the one-shot are connected to the prohibitory input of the BANCH circuit, the output of which is connected to the input of the signaling and shutdown unit, the second output of which is connected to the second inputs of the coincidence circuit via the time delay circuit and is connected to input calibrated divider. Sources of information taken into account in the examination 5 1. Japanese Application No. 3 -16436, cl. 111A22, Republican. 1979 2. Patent of France No. 205870, cl. G 01 P 3/00, published. 1971 (prototype). R / rf YES Al All Xf