SU1410250A1 - D.c. electric drive with two-stage mechanical gearing - Google Patents

Abstract

The invention relates to electrical engineering and m. Used for embedded dead-stroke (MX) control of two-stage mechanical transmissions of DC drives. The purpose of the invention is to expand the functionality by providing built-in control of THEIR during operation. The actuator includes an electric motor 1 connected to the load 2 through the mechanical transmission 3, the sensor 4 of the main current and the driver 5 pulses. The device has two circuits for counting pulses, the number of which is proportional to the amount of dead strokes at, and pt of the first and second stages of mechanical transmission. Each circuit consists of a trigger 6 (10), logic elements NOT 13 (14), AND 7 (11) and counter 8 (12), equipped with a display with indication. 2 il. (ABOUT

Description

u sd

The invention relates to electro-texHHKe and can be used for the built-in monitoring of the dead strokes of two-step mechanical ne 1) power supply of direct current electric drives.

I The purpose of the invention is to expand (functionality by providing built-in control for dead moves during operation.

FIG. 1 is a block diagram of an electric drive; in fig. 2 - timing charts of the device.

A direct current drive with a two-stage mechanical transmission contains an electric motor 1 connected to load 2 via a two-step mechanical transmission 3 The sensor 4 of the electric current rf, the driver 5 pulses, the trigger 6, the logic element 7 and the counter 8 and the display are connected together.

The generator 9 pulses output connected to the second input of the logic element I. In addition, the drive contains connected in series the second trigger 10, the second logic element And 11c three inputs and the second counter 12 with the display. The first logic element AND 7 is provided with a third input connected to the output of the first logic element NO 13. The input of the first logic element NO 13 and the output of the second trigger 10 are connected to the output of the first trigger 6 by the first input. The second inputs of both triggers are combined and connected to output O. Install O. The output of the first trigger 6 through the second logic element is NOT connected to the second input of the second logic element And 11, the third input connected to the generator 9 pulses.

The drive works as follows.

Before starting the process of measuring the dead strokes of the two-stage mechanical transmission 3, the dead stroke oi of the high-speed and intermediate shaft is set to the maximum position c6 of the intermediate and low-speed shaft. The pulse generator 9 generates a sequence of pulses and, with the period following Tu (figv), which are supplied

0

five

0

five

0

five

0

five

0

five

At the inputs of logic elements, And 7 and 11. In the initial state, the triggers 6 and 10 at the output have low (zero) potentials O and U pftiO in the interval 0 t with t in FIG. 2g and d, which are fed from trigger 6 to the input of the logical element 7,. and from the trigger 10 to the input of the logical element 11, therefore, the logical elements 11 and 11 are closed.

At time t (FIG. 2), the DC motor 1 is started. In the winding of the core of the electric motor 1, a starting current pulse arises which generates a voltage pulse on the sensor 4 (V 4-i at the time t in Fig. 2a). The front of the voltage pulse U, from sensor 4, is applied to the pulse shaper 5, where it is differentiated, amplified and limited. The generated voltage pulse of the driver 5 (Uj at time t in Fig. 2b) enters the input of trigger 6 and brings it to a state characterized by a high potential at the output (U g at time t, in Fig. 2d). With the release of the trigger. 6, a high potential is applied to the second input of logic circuit 7. 7. The trigger 10 remains in its initial state (and, OI O at time t, fig.2d), its low output potential is inverted by the logical element HE 13 and fed to the input of the logic element And 7, which since time t, transmits the pulses produced by the pulse generator 9 to the counter 8 with the indication

last starts counting pulses. I

In the time interval t «t - t

(Fig. 2) the electric motor 1 and the high-speed shaft of the two-stage mechanical transmission 3 come into rotation, the starting current and the voltage on the sensor 4 decrease exponentially (interval tt "t / i of fig.2a), but the intermediate shaft of the two-stage mechanical transmission 3 does not is moving because the dead speed oi of the high speed and intermediate shaft is not yet selected. The counter 8 counts the pulses from the pulse generator 9 through the open logic element AND 7. The output signal of the logic element AND 7 is shown in FIG. 2e (interval, t, t: t). Trigger 10 remains in source co31

then research institute (11.0 о in the interval t, t

t in FIG. 2e) and its low output potential is fed to the input of the logical element 11 and keeps it in the closed state.

At time t (Fig. 2), the dead stroke c (a, high-speed and intermediate shaft is selected, the intermediate shaft of the two-stage mechanical transmission 3 is brought to its working position, the load on the electric motor 1 increases abruptly, which causes a current pulse in the core and a pulse voltage on the sensor 4 (Ug at time t in Fig. 2a), which is applied to pulse shaper 5. Shaper pulse 5 produces a second pulse (U, at time t in Fig. 26), which enters the trigger input 6 and puts it into a state Induced by a low potential at the output (and J CZ O at the time point tg in FIG. 2d). The low potential of the output of the trigger 6 is transmitted to the input of the trigger 10 and translates it into a state characterized by a high potential at the output (U, at t in Fig. 2d). A low potential from the output of the trigger 6 is supplied to the second input of the logic element AND 7, in addition, a high potential from the output of the trigger 10 is inverted by the logical element NOT 13 and fed to the input of the logical element AND 7, the latter is closed and the arrival of pulses from the generator 9 pulses on counter 8 is stopped (U-j at time t in FIG. 2e). The number of pulses n, counted during the selection of dead run oi, speed and intermediate shaft of mechanism 3, is displayed on the display of the counter 8.

t, t - t, (1)

At this point in time t (Fig. 2), the high potential from the output of the trigger 10 is fed to the first input of the logic element 11 and the low potential of the output of the trigger 6 is inverted by the logic element NOT 14 and fed to the input of the logical element 11, which since time t transmits pulses generated by the generator 9 pulses on the counter 12, the latter starts counting pulses.

50

In the time interval tt - t (Fig. 2), the intermediate shaft of the two-stage mechanical transmission 3 is rotated. The starting current and voltage on the sensor 4 decrease exponentially (the interval tt .tj in Fig. 2a), but the low-speed shaft of the two-stage transmission 3 It does not move, since the dead stroke jt of the intermediate and the thrust shaft is not yet selected. The counter 12 counts the pulses from the pulse generator 9 through the open logic element 11. The output signal of the logic element 11 11 - U ,, is shown in FIG. 2g (interval C. t,). At time tj (figure 2) the dead stroke d of the intermediate and low-speed shaft is selected, the low-speed shaft of the two-stage mechanical transmission 3 is set to rotate, the load on the motor 1 increases abruptly, which causes a current pulse in

the winding of the core of the electric motor 1 and the voltage pulse on the sensor 4 (and at time tj in Fig. 2a), which is applied to the pulse shaper 5. Shaper 5 pulses

produces a third pulse (U at time tj in Fig. 2b), which enters the input of trigger 6 and translates it into a state characterized by a high potential at the output (and, at time t, at

Fig. 2d), and the trigger state 10

remains the same - at its output is a high potential (U at time t in Fig. 2e). The high potential from the output of the trigger 6 is fed to the second input of the logic element And 7, and the high potential from the output of the trigger 10 is inverted by the logical element NOT 13 and fed to the first input of the logical element And 7 and keeps the latter closed. The high potential from the output of the trigger 6 is inverted by the logic element HE 14 and fed to the input of the logic element 11, the latter is closed and the flow of pulses from the driver 5 pulses to the counter 12 stops (U, at time tj in Fig. 2g). The display of the counter 12 is displayed on the display of the number of pulses n, counted during the selection of the dead run nL of the intermediate and low-speed shaft of the mechanism 3

14

At.

t, - t,

zTu

(2)

Mathematical expressions for which the magnitude of the dead strokes flt can be calculated at a known value of t and t, and ei of the two-stage mechanical transmission 3,

ci. , T - TD (1-6), (3)

firt

  f- - (1 e TA) (4)

Where

about 6g

I

N

rated engine speed 1

at

about.1. L

TD4 - electromechanical constant of engine time 1, s;

TC is the pulse repetition period of the generator 9 pulses, s;

p and Hg - the number of pulses read in the information display of the counters 8 and 12 - dimensionless values i N - gear ratio

high-speed and intermediate shafts of a mechanical gear 3 - dimensionless dimension When substituting the values in specified dimensions into the formula (3) and (h) in the specified dimensions, the results of calculations of the dead strokes (1 (high-speed and intermediate) and a6j (intermediate shaft and low-speed shaft) will be obtained in D) hell with ah.

506

Claims (1)

Invention Formula DC power supply with a two-stage mechanical transmission, containing an electric motor connected to the load through two. - step mechanical transfer, consistently connected sensor motor current, pulse shaper, trigger, logical ground and pulse counter with indication, pulse generator, connected to the second input logic element And, characterized in that, in order to extend the functionality by providing built-in control of dead strokes in the process operation, the second trigger, the second logical element And with three inputs and the second pulse counter with indication, two logical the element is NOT, the first logical element And is equipped with a third input connected to the output of the first logical element NOT, the input of which is connected to the output of the second trigger, the first input connected to the output of the first trigger, the second inputs of both triggers are combined and connected to the installation terminal O, the output of the first trigger through the second logic element is NOT connected to the second input of the second logic element I, the third input is connected to the output of the pulse generator.