SU1527703A1 - Device for controlling stepping motor - Google Patents

Abstract

The invention relates to electrical engineering and can be used to create a discrete electric drive for an object with a limited range of motion. The purpose of the invention is to increase reliability. The device provides continuous monitoring of the state of the elements limiting the range of movement, eliminating false blockage of movement when working out the limit positions in the microdisplacement mode, when the working stroke of the pushbutton of the limit switch 4 is processed by several movements of the controlled object and thereby increases the reliability of control of the emergency situation work with a limited range of motion. For this, the device contains the first 13 and second 22 elements 2 OR, element 4 OR 15, the one-shot 14 and the counter 16, the blocking signal at the output of which appears only in the case when the displacement of the controlled object exceeds the working stroke of the limit switch. 2 Il.

Description

Mr. J

ate

ND

About WITH

(Shgg /

The invention relates to the control of electrical machines and can be used to create a discrete electric drive for an object with a limited range of motion.

The purpose of the invention is to improve reliability when working with a limited range of movement.

Fig. 1 is a functional block diagram of a device for controlling a stepper motor; Fig. 2 shows stress plots at the nodal points of the circuit.

A device for controlling a stepper motor contains a clock bus 1, a bus 2 directions, a resolution bus 3, limit switches 4, resistors 5-8 first 9 and second 10 triggers, first and second 2 elements of the IS1 SHOCCH1 OR, first element 2 of ILN 13, one-oscillator 14 , element 4ILI 15, counter 16 element 2И 17, control unit 18, consisting of the element NOT 19, the first

20 and the second 21 4I-NOT elements, the second 2ILI element 22, the pulse distributor 23 and the multichannel power amplifier 24, the inputs of the multi-channel power amplifier 24 are connected to the corresponding outputs of the pulse distributor 23, the inputs of which are connected to the outputs of the first 20 and second 21 elements 4I-HE , the first inputs of the latter are connected to the bus 3, the second inputs of the first 20 n second 21 elements 4I-NOT are connected

with the output of element 2I 17, the first input of which is connected to bus 1, the third input of the second element 4I-NOT,

21 through the element NOT 19 and the third input of the first element 4I-NOT 20 is connected to the bus 2 directions, the fourth inputs of the first 20 and second 21 elements 4I-NOT are connected respectively to the first and fourth inputs of the element 4ILI 15 and the outputs of the first 9 and second 10 triggers, installation inputs through resistors 5,

6 and 7, 8 are connected to the power bus and through limit switches 4 to buses of zero potential, and are also connected to the inputs of the first 11 and second 12, respectively, EXCLUSIVE OR, the outputs of the latter are connected to the inputs of the first element 2IL 13, the output of which is connected to the third the input element 4ILI 15 and through one vibrator 14 with the second input element 4ILA 15, the output of which is connected to the input of the zero setting of the counter 16,

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the output of the latter is connected to the second input of the element 211 17, and the counting input of the counter 16 is connected to the output of the second element 2ILI 22, which is connected by its inputs to the outputs of the first 20 and second 21 elements 4I-NOT,

FIG. 2 shows plot 25 (1) - clock input I (clock frequency); plot 26 (9-S) - S-input of the first trigger 9, disconnecting contact of the corresponding limit switch and the first input of the first element IGKLYU- OR 11; plot 27 (9-R) - R-input of the first trigger 9, the closing contact of the limit switch and the second input of the first element ISKGPAChAUPEEE or 11; plot 28 (9) - the output of the first trigger 9; plot 29 (11) - the output of the first element EXCLUSIVE OR 11; plot 30 (14) - output of one-shot 14; plot 31 (15) - the output of the element 4ILI 15; plot 32 (2) is the signal level at the input 2 of the direction; plot 33 (20) - the output of the first element 4I-NOT 20; plot 34 (21) - the output of the second element 4I-NOT 21; plot 35 (22) - the output of the second element 2ILI 22; plot 36 (16) - the output of the counter 16; plot 37 (17) is the output of element 2 and 17 and the clock input of the control unit 18.

The device works as follows.

Suppose that in the initial state (time T1, FIG. 2) the controlled object is not in one of the limit positions, t, e, none of the limit switches 4 is pressed. The first 9 and second 10 triggers are set in one state due to the passage of a logical zero through the opening contacts of the limit switches 4 to the S inputs of the trigger 9 and 10, At the outputs of the first 11 (plot 29) and the second 12 elements EXCLUSIVE OR there are potential signals of high level coming to the inputs of the first element 2ILI 13, which provides the addition of low level signals by OR, and that caKfciM at the output of the first element 2IL 13 there is a high level signal, From the output of the one-shot 14 The signal at its input removes a high level signal, so that all signals arriving in the initial state at the inputs of element 4IL 15 have a high level and at the output of the element

15, providing the addition of OR

low level signals, a high level signal is present coming at the zero input of the counter

16 and providing a reset, in which a high level signal is set at the output of the counter 16

(the counter may include a decoder decrypting the specified connection of the counter, for example, after highlighting eight pulses).

The high signal from the output of counter 16 (plot 36, time T1) arrives at the second input of element 2I 17 and does not prevent the passage of clock pulses through element 17. When a high signal is applied to bus 3 at the first inputs of the first 20 and second 21 elements 4I-NOT potential high-level signals are present, removing the ban on the passage of clock pulses through the first 20 and second 21 elements 4I-NOT. However, the distributor has 23 pulses, the multichannel power amplifier 24 and the stepping motor clock pulse, do at time T2, passes only through the first element 4H-HE 20, the choice of which and thus the rotation of the engine in a given direction is determined by the level of the potential signal at input 2, the negative clock pulses through the second element 21 of the output of the first element 4I-II 20 22 arrive at the counter input of counter 16, which is blocked by a high level signal applied to the zero input of the counter.

At the time of the TZ, the controlled object reaches one of its limiting positions. In this case, the switching contact of the corresponding limit switch begins to move away from the opening contact (plot 26) with some chattering ending by the time T4, and after the switching contact is disconnected from the opening switch on the last (due to resistor R 6) a high level that does not change the state of the trigger 9, but causes the appearance of a low level signal at the output of the first element of the UIT and EOI OR 1 1, coming further through the first element 2ILI 13 to the third input of the element 4ШШ and the input one-shot 14. By differential

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The one-shot 14 signal generates a negative pulse, the duration of which is chosen such that the one-shot 14 is restarted by each subsequent bounce signal difference, thereby forming a negative pulse at its output up to time point T5 (plot 30).

After the next clock pulse arrives at time T6, the switching contact of the limit switch, due to further displacement of the controlled object and the push switch of the limit switch, comes into contact at time T7 with the closing contact, causing some chattering until the time point of the TZ. According to the signal drops when bounce, the one-shot 14 until the time T9 continues to form a negative impulse as described. At the first contact of the switching contact with the closing first trigger 9 is transferred to the zero state, blocking the passage of clock pulses through the first element 4I-HE 20 and ensuring further maintenance of the low signal at the output of the element 4IinH 15. Starting from the time point of the TZ to point of time T7, the low level signal at the output of element 15 is maintained due to the arrival at its inputs of low level signals from the output of the One-Vibrator 14 and the first element of the IC1SChochL (LECEE OR J 1, respectively. E This low level signal arrives at the zero-setting input of counter 16, enables the counting, and the counter starts counting the clock pulses starting from the time point of the TOR. After the time point T7 the clock pulses go to the distributor 23 pulses and thus the counting input of the counter 16 stops due to for blocking movement in this direction and is resumed only after time T10, when by changing the signal level at input 2, the passage of clock pulses through the second element 4I-NOT 21 is allowed. tim clock pulse at time T11 object begins to move down from the end of the switch and its switching contact begins to retreat at a time T from the switching contact 12 also

At the same time, the described process of chattering and the formation of negative signals at the outputs of the first element EXCLUSIVE IL1 11 and single-vibrator 14 is caused. After the application of a certain number of clock pulses necessary for the object to exit the limit switch, the switching contact at time T13 contacts the normally open contact, causing returning the first trigger 9 to the one state. At the same time, the low level signal at the output of the AILI 15 element is maintained due to the restart of the one-shot 14 n moment of time T 14 and the formation of a negative pulse at its output up to the time point T15. Upon completion of this pulse at time T15, only the high level signals are present at all inputs of element 4IL 15 and the high level signal appears at the output of element 15 and resets the counter 16 to its initial state and does not change the signal at its output, while the counter 16 counts the number of clock pulses necessary for the normal operation of the limit switch, i.e. for us: yes a controlled object to and from the limit switch, and this number is less (by 1-2 pulses) of the number decoded at the output of the counter.

The movement of the object in the opposite direction B continues normally, for example, up to time point T16, when the communication line terminates at the breaker. At the inputs of the first element, TURNING OR 11 (epyuoy 26 and 27), signals of the same high level appear, causing a low level signal at the output of element 11 (plot 29) and the same at the output of element 4IL1 15 (plot 31). For counter 6, this signal is the counting enable signal and the counter begins to count clock pulses arriving at its counting input from the output of the second element 211PI 22 (plot 35). By reaching the number decoded at the output of the counter, the low level of the output signal of the counter 16 blocks, at the time T17, the passage of clock pulses through the element 2I 17 and thereby causes the stepping motor to stop, and

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This can only be removed after the fault has been rectified. A low-level signal that occurs when the limit switches malfunction or their connection line 11 at the counter output can be used to indicate an emergency situation,

The closure of the communication lines of the limit switch to the housing or between each other, and also the breaking of the limit switches results in an anapotny result, i.e. to blocking movement.

The second trigger 10 and the second element EXCLUSIVE 1 SHI 12 function in a similar way, providing, together with the rest of the device element, regular testing of the second of the limiting positions of the controlled object in mode 1–1 displacement 1.

The pulse distributor 23 forms, when the device is in operation, a series of pulsed C1 cushions required for switching the windings of the selected stepper motor and amplified by a multi-channel power amplifier 24.

Thus, the proposed device with thio provides a higher degree than the known accuracy of controlling an emergency situation when controlling an object with a limited e; displacement of movement when limiting positivities in the 1-1-micro mode: when the working stroke of the push-switch of the limit switch is processed by means of several clock pulses.

Claims (1)

Invention Formula U s-roist in step for control by a stepper motor, containing a series-connected multichannel power amplifier, distribution of an impeller, 1 control unit, with a control input and a direction input, connected to the corresponding buses, and a clock an input connected to the input of element 2I, the first input of which is connected to the clock bus, as well as two elements of the IS1SHOCH10CHIE OR or two triggers, each connected to one of the ends of the output switches n with the inputs of one of the elements EXCLUSIVE 1 | DI, and s With these, with the inputs of the control unit, characterized in that, in order to ensure reliability when working with a limited range of movement, the first and second elements 21SH, element 41SH, one-oscillator and counter, the output of which is connected to the second input of element 2I, are entered. connected to the output of the second element 21, connected in with the outputs of the control unit, and the input of the zero meter installation is connected to the output of the 4NL11 element, the inputs of which are connected to the trigger outputs, the output of the first element 2IL, and the output of the one-vibrator connected by the input to the output of the first element 2IL, the inputs of which are connected to the outputs of the elements IC1SHYuCHA1EPa OR.