SU1299539A1 - Apparatus for automatic estimating of load of revolving cutting working member - Google Patents

Abstract

FIELD OF THE INVENTION The invention relates to agricultural machinery. The aim of the invention is to increase the productivity of a combine by timely detection of excessive blunting of knives or a counter-cutting bar. When the processed mass enters the cutting drum, a torque sensor (D) 1 produces an analog electrical signal proportional to the torque value. At the same time, D 2 rotational speed produces pulses, the frequency of which is proportional to the angular velocity of rotation of the drum. Upon enrolment

Description

The feed mass D 4 produces an analog signal proportional to the thickness of the layer of the incoming mass. This signal is fed to the input of comparator 5. When a layer exceeds a certain mass, the unit potential from comparator 5 is fed to the inputs of all coincidence circuits 8, 9, 10 and 11, opening circuits 8 and 9 to pass signals with D 2 and timer 3, Signals from D 1 and D 4 through analog-digital converters 6 and 7 and circuits 10 and 11 are fed to the inputs of memory registers 14 and 16, asD2- to the input of register 15. At the same time, the falling edge of the pulse from the output of timer 3 after the time delay to the element to agricultural machinery engineering, namely to the device ystvam for controlling the operation of working bodies kormouborochngh combines, In particular for evaluating the degree of blunting of the cutting drum blades.

The aim of the invention is to increase productivity by timely detecting excessive blunting of knives or a counter beam.

The drawing shows a diagram of the proposed device for automatic evaluation of the load of a rotating cutting tool.

The device contains a torque sensor 1, a rotation speed sensor 2, a timer 3, a mass arrival sensor 4, a comparator 5, analog-digital converters 6 and 7, two input circuits 8 and 9, three matches three input circuits 10 and 11, pulse counter 12, pulse time delay element 13, memory registers 14-16, microcomputer 17 and indicator 18.

Structural diagram of the device re

It is altered using serial micro circuits. The low demands placed on the number of commands executed by the microcomputer and its speed can be used for this purpose.

13, enters the Reset input of the counter 12 and, after resetting it, prepares for the next pulse counting. At the same time, the trailing edge of this pulse enters the input of microcomputer 17, in which the current power on the cutting drum shaft is calculated, and allows registering values of registers 14, 15 and 16 to be overwritten. The resulting specific power consumption value is then compared with the target, received when working with new knives. When the current specific power consumption is significantly exceeded, a decision is made to regrind the knives. 1 3 i p. F-ly, 1 ill.

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 ABOUT

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targets programmable microcalculator with built-in communication channels Electronics MK-46, or electronics controller K1-20.

A multivibrator assembled according to any of the known schemes is used as a timer.

An electromagnetic-type design is used as speed sensors. A non-contact sensor is used as a torque sensor.

The mass arrival sensor is made in the form of a variable resistor with a linear characteristic, the slider of which is mechanically connected to the axis of the upper rollers. The resistor is fed from a stabilized source of constant voltage, a feedstuff, the spring-loaded upper rollers are raised in proportion to the thickness of the layer of feedstuff. Moving the rollers causes the slider to move and the voltage taken from it, which is fed to the input of the analog-to-digital converter, changes.

The device works as follows.

During the operation of the combine, the processed mass (grass, corn, etc.) enters the cutting drum

on grinding. The torque sensor 1 mounted on the drum shaft outputs an analog electrical signal proportional to the torque value. At the same time, the rotation speed sensor 2 generates pulses, the frequency of which is proportional to the angular velocity of rotation of the drum. This data is sufficient to calculate the power consumed by the rotation of the drum, which is calculated by the microcomputer 17.

To determine the angular velocity, it is necessary to measure the number of pulses per unit time. For this purpose, the device has a timer 3, which produces periodic pulses, for example, with a period of 1 s.

When the feed mass arrives, the sensor A generates an analog signal proportional to the thickness of the layer of the incoming mass. This signal is fed to the input of the comparator 5, the output of which produces a voltage drop in the event that the value of the incoming mass exceeds a certain value. A single potential from the comparator output is fed to the inputs of all matching circuits by opening two-code circuits 8 and 9 for passing signals from the output of the speed sensor 2 and timer 3.

When a signal appears at the output of circuit 9, it arrives at the second inputs of three-input circuits 10 and 11, on the third inputs of which there is already a signal from the output of comparator 5. The signals from the outputs of analog-to-digital converters 6 and 7, which are digital The signal paths from the outputs of sensors 1 and 4 arrive at the first inputs of circuits 10 and 11, and pass through them to the inputs of memory registers 14 and 16.

Writing to registers 14-16 of memory will occur when a back edge of a pulse generated by timer 3 arrives at their second inputs. In this case, register 14 recorded the previously measured torque value on the drum shaft, and the number of impulses will be overwritten into register 15 received at the input of the counter 12 from the speed sensor 2, and the register 16 will record the value of the forage mass that entered the cutting drum.

The falling edge of the pulse from the output of timer 3, after a time delay carried out by the element 13, arrives at the fta. Resetting the counter 12 and resetting it, prepares to count the number of pulses in the next time interval. At the same time, the leading edge of this pulse arrives at the input of the microcomputer 17, allowing the machine to overwrite the values of registers 14-16 in the memory of the machine.

In microcomputer 17, the current power calculated on the shaft of the cutting drum is calculated by the formula

N

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hp

5 o

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Q

Q

where M is the magnitude of the torque;

n - the number of revolutions of the shaft. The resulting power value is divided by the value of the feed mass fed into the cutting drum. The obtained value of the specific power consumption for cutting the unit of the fodder mass is compared with the set value obtained when working with new or re-sharpened knives. The comparison can be carried out automatically in the computer memory or by the mechanic with the help of the indicator 18. At significant power densities, the decision is made to regrind the blades.

The presence of a comparator with a set voltage level at one of the inputs eliminates the calculation of specific consumption in the absence of forage, for example, on turns. Otherwise, the microcomputer will crash due to division by zero. In the absence of a mass or a small amount of it, the value of the output signal of sensor 4 is less than the voltage set at the comparator and from the top of the comparator 5 to one of the inputs of all coincidence circuits, the zero level is received, thus closing all measurement channels. By increasing the volume of incoming mass to the threshold level at the output of the comparator 5, a single level is produced, which opens the matching circuits 8 and 9, and the output from the output of the matching circuit 9, together with the output signal of the comparator opens the matching circuits 10 and 11.

Claims (2)

Formula inventions 1299539 ni A device for automatically estimating the loading of a rotating cutting tool, comprising torque and speed sensors mounted on its shaft, interacting with an electronic control circuit containing, in particular, a pulse time delay element, characterized in that, in order to increase productivity by timely detecting oversized blunting of knives or a shear bar, it is equipped with a sensor for feeding forage, and the electronic control circuit has a time rum, comparator, analog-to-digital converters, two-input and three-input matching circuits, memory registers, pulse counter, micro-computer and indicator, while the output of the feed mass sensor is connected to the inputs of the comparator and the first analog-digital converter, the outputs of which connected respectively to two inputs of one of the three-input coincidence circuits, to the third input of which the output of the first two-input coincidence circuit is connected, the inputs of which are connected to the outputs of the timer and the comp. move the same coincidence circuit is also connected to the inputs of the three registers recording memory you five the strokes of which are connected to the microcomputer inputs, and the input of one of the memory registers is connected to the output of the first three-input matching circuit, the input of the second memory register is connected to the output of the pulse counter connected via another two-input coincidence circuit with the rotational speed sensor input, the second input of this coincidence circuit is connected to the output of the comparator, the fault input of the pulse counter is connected to the output of the time delay element, the input of which is connected to the output of the first two-input coincidence circuit, and the input of the third reg through another analog-to-digital converter and the second three-code matching circuit is connected to the output of the torque sensor, the second and third inputs of this matching circuit are connected to the second and third inputs of the first three-input matching circuit, one of the microcomputer inputs is connected to the output block time delay, and the output of micro-computers - with the indicator. 2. The device according to claim 1, wherein the intake sensor for the feed mass is made in the form of a variable resistor fed by a stabilized DC voltage, the slider of which is mechanically connected to the axis of the upper rollers and electrically - with an analog-to-digital converter input. 0 five 0