SU600263A2 - Device for controlling drive of single-bucket excavator - Google Patents

Description

The control component comprises a functional gain converter and an analog adder, the output of which is connected to the corresponding input of the functional gain converter.

FIG. 1 is a block diagram of the described device; in fig. 2 - input characteristic - output of a nonlinear element with an adjustable dead band; in fig. 3 is a graph of the total value of the maximum torques of the engines against the magnitude of the displacement at the optimum coefficient of heat load.

The drive control device of the single-bucket excavator contains a pulse sensor 1 of magnitude and direction of movement, a digital-to-analog speed sensor 2, a current sensor 3 and a sensor 4 of the first time derivative of the current, a sensor 5 of the second time derivative of the program control block 6 consisting of a software block 7 control, trigger 8, two reversible counters 9, node 10 specifying the direction of movement, trigger AND and converter code - voltage 12, control law shaping unit 13, block 14 dynamic components up the generator, the exciter exciter 15, the drive maximum torque control unit 16, consisting of the storage register 17, the converter code - voltage 18 and the nonlinear element 19 with adjustable deadband. The block of dynamic components of the control action includes an analog adder 20, to the output of which a function converter 21 is connected.

The device works as follows.

The initial entry of the task is carried out by the operator by moving the rotary platform of the excavator to the required angle during manual control and supplying a program offset signal to one of the reversible counters 9 through the node 7. When moving the platform, a pulse sensor of the magnitude and direction of movement produces pulses, the number of which is proportional to the amount of movement. The outputs of sensor 1 are connected to the counting inputs of two identical reversible counters 9. Depending on the direction of movement, one of the counters operates in the addition mode (writing) and the other in the subtraction (writing off) mode. Synchronous switching of counters 9 to write or write off produces a trigger 8, depending on the sign of the speed of the turntable of the excavator. In the counter 9, to which the write bus is connected, the count and memorization of the number of pulses coming from the pulse sensor 1 and their algebraic summation with the program shift signal occur. From the counters 9, the information about the amount of movement enters the storage register 17. In the storage register 17

full information about the amount of movement in this cycle is stored, recorded in any of the counters 9 or rewritable from one counter 9 to another during the movement

object. From the output of the storage register 17, this information enters the converter code - voltage 18 and the functional converter 21 of the transmission coefficient. In the code-voltage converter 18, the information on the total amount of movement is converted from digital to analog and then fed to the input of a non-linear element 19 with adjustable deadband, the characteristic input-output of which is shown in FIG. 2. The width of the dead zone of the characteristic of the non-linear element 19 is directly proportional to the magnitude of the displacement. Pelinear element 19 is included on the current feedback day of the core.

system GD, therefore the magnitude of the maximum current of the cor (motor torque) is directly proportional to the width of its deadband. Consequently, with the operation of the control unit 16

the drive torque, the value of the maximum torque, depending on the magnitude of the movement, varies according to the law shown in FIG. 3,

where L is the total moment of the engine,

lei in relative units;

Mmais. - the maximum value of the moment developed by the engines;

Mn is the rated torque of the engines;

f - movement;

frasch - calculated amount of movement.

A device that implements such a law, the change in torque from the magnitude of the displacement, allows the engine heat load coefficient to be maintained at an optimal level. Therefore, before the object starts moving in automatic mode, the cyclic movement program is entered and memorized in the single-blade excavator's drive control device, the maximum torque of the drive and the transmission coefficient of the total signal from current sensors and its derivatives are selected as a function of the specified movement. This is where the program entry process ends. At the operator's command to move automatically in a given direction, the node 10 specifying the direction of movement sets the corresponding counter 9 to the initial state and connects the converter code - voltage 12 to another counter 9 from which information is copied. After the counter 9 is connected to the converter, the code - voltage 12 from the latter is signaled about the magnitude of the movement in the formation unit 13

control law and begins the process of working out the task automatically.

When the excavator is moved, the pulses from sensor 1 produce a charge off of information from a counter connected to the converter code - voltage, and writing it to another counter.

Thus, a similar pattern of operation of the counters 9 ensures the safety of information about a given program and the determination of the current value of the movement error of the POROT excavator platform in the entire range of motion of the system. The control algorithm is formed in block 13 of the formation of the control law by algebraically adding and amplifying signals proportional to the error in mixing, the speed of the object, the current of the core and its first and second DERIVATIVES in time. These signals are fed to the control law generation unit 13, respectively, from the program control unit 6, the pyro-analogue SPEED sensor 2 and the transfer function converter 21. The signal converted into block 13 is fed to the input of the exciter generator 15, ensuring the reproduction of a given movement with a near-optimal speed.

Claims (3)

1. Device for driving a single bucket excavator according to the author. St. No. 442271, characterized in that, in order to increase the reliability of the drive and increase the performance of the excavator, a dynamic impact control component and a maximum drive torque control unit are inserted into the excavator, the inputs of which are connected to the drive root and software control outputs, respectively and the outputs to the input of the exciter generator and the corresponding input of the block of dynamic components of the control action, the other inputs of which are connected respectively to the outputs tchikov current and its first and second derivatives with respect to time, and an output connected to the input unit generating a control law. 2. The device according to c. 1, characterized in that the maximal control unit, 1n of the drive torque includes a storage register, a code-voltage converter and a non-linear element with a dead-band regimen, the input of which is connected via a code-voltage converter to the storage register output. 3. The device according to c. 1, characterized in that the block of dynamic components The control action includes a functional gain converter and an analog adder, the output of which is connected to the corresponding input of the functional gain converter. Sources of information taken into account in the examination I. USSR author's certificate LL 442271, cl. E 02F 9/20, 1972. r F-Q)% i J l i / i th jr , ZC % Estimated