SU1435189A1 - Method and apparatus for emergency stop of rollers of feeding apparatus for forage harvester - Google Patents

Abstract

FIELD OF THE INVENTION The invention relates to the field of agricultural engineering, in particular, to safety devices of the working bodies of fodder harvesters. The purpose of the invention is to increase reliability by preventing foreign objects, mainly stones, from entering the combine shredder. The essence of the method of an emergency stop of the rollers of the feeding apparatus of a forage harvester consists in the following. By means of the sensor 9, the torque is continuously measured at the Vapets 2 and 3 drive. The control signal is analyzed for duration and frequency with the aid of an electronic unit 10. A pulse signal of torque increment is extracted to the drive of the rollers and the amplitude of this signal is measured. It is compared in the comparator 12 with a permissible threshold, which is set by the sensor 13 threshold. The resulting signal is formed and sent a command to the brake 8 to stop the drive of the rollers 2, 3. 2 sec. f-ly, 1 ill. i (L O9 SP CX

Description

 1435189

FIELD OF THE INVENTION The invention relates to agricultural machine building, and

Power expended on the message to the plant mass kinetic

but to the safety devices of the working organs of fodder harvesters.

The purpose of the invention is to increase reliability by preventing foreign objects, mainly stones, from falling into a combo shredder.

The drawing shows a functional diagram of the device for an emergency stop of the rollers of the feeding apparatus of a forage harvester.

The essence of the method of emergency dewatering of the rollers of the feeding machine, the Combine Harvester, concludes with and the following.

When the plant mass passes through a pair of compacting rollers, the power expended on the three-drive is determined by the following ratio,

(un nud + nvhh + n x). (one)

where is m and to

pN, upA j N KMri and N

torque and rotational speed of the drive shaft

 -. power expended

on compaction, the message of kinematic energy to the vegetable mass and idling.

Considering the costs of idling to be constant, consider the change in the magnitude of the torsional torque on the drive of the rollers during the passage of a foreign object, for example, a stone.

Power expended on compaction

N UPA

where f f G V

(2)

coefficient of friction of the mass of the rolls G - the force of compression of the plant

masses;

V - vegetation mass transfer rate

In turn, the compression force is determined by

G

Gokd

de G.

k

D is the compressive force at the initial gap, the spring constant;

the increase in clearance caused by the passage of plant mass or stone

energy,

Q v

N

KIM

J

(four)

where Q is the second supply of vegetable

masses.

When passing through a pair of stone rollers with an average diameter D, the power components defined by expressions (2) and (4) increase by the following values:

five

N

(upl

fk G v;

N

Khh

m T

(5) (6)

np

20 where m is the mass of the stone;

t np v

the time of interaction of the stone with rollers;

25

e

thirty

R

-35

40

45

50

55

k

coefficient of stone firing on rollers.

Analysis of expressions (5) and (6) shows that for typical parameters of a pair of compacting rollers (G 2000 N, the initial gap is 2–5 cm) the stone with a mass of 0.5–0.6 kg and an average diameter of 6–8 cm is already passing causes a short-term increase in torque per drive of a pair of rollers by 30-60%. And the duration of the moment increase is determined by the time of interaction of the stone with the rollers and can be 0.02-0.1 s.

Thus, the passage of the stone through a pair of compacting rollers, if the thickness of the stone C11 is equal to the thickness of the vegetable mass layer or several more, is accompanied by a short-term increase in the torque on the drive of the rollers. And the simultaneous carrying out of amplitude and time analyzes allows to identify the passage of the stone. Duration analysis can also be performed by frequency filtering. The increase in torque, caused by an increase in the mass supply, is longer and smoother, which is a prerequisite for the signal to be passed.

Thus, by analyzing the control signal in terms of duration and frequency, the pulse signal is incremented in torque, its amplitude is measured, compared with the allowable threshold, and a command to stop the drive of the rollers is generated and the resulting signal is received.

The device for emergency stop of the rollers of the feeding machine of the forage harvester contains successively arranged feeding mechanism 1 and the feeding machine, made in the form of a pair of rollers 2 and 3, and the upper roller 3 is made floating and spring-loaded due to the spring 4, the drive of rollers 2 and 3 does not cut the shaft 5 and the clutch 6 is connected to the engine 7. The driven shaft 5 is connected to the brake 8. A torque sensor 9 is mounted on the shaft 5, the output of which is connected via an electronic unit 10 to the control input of the brake 8. The electronic unit 10 contains a filter 11 ezhutochnoy hour Toty coupled to the comparator 12, the other input of which is connected to the threshold setting unit 13.

The feed mechanism 1 directs the crop, in which there may be stones, into the feeding apparatus. The latter compresses the mass and travels to a grinding apparatus (not shown). The compression force is regulated by means of the spring 4. The rollers are driven from the engine 7 through the coupling 6,

When a foreign object, for example a stone, passing through a pair of rollers 2 and 3 with dimensions not less than the thickness of the vegetable mass layer, the torque to the roller drive increases for a short time. The torque is measured continuously by the sensor 9, and the electronic block 10 by analyzing the amplitude and duration of the torque rise identifies the passage of a foreign object. For this, a priori set the threshold amplitude and pulse duration.

The separation of signals of different durations is carried out by frequency filtering using appropriate frequency filters. The amplitude of the filtered signal, containing information about rapid changes in torque when a foreign object passes, is compared with the threshold of the comparator 12. When the threshold at the output of the composite is exceeded

Q 5 0

5 o

. "

0 5

five

Parator 12 is signaled by the presence of a foreign object.

When the stone passes through a pair of rollers 2 and 3, the electronic unit 10 prepares a command to activate the brake 8, which carries out an emergency braking of the feeding apparatus and thereby prevents the ingress of a foreign object into the chopper.

Claims (2)

1. An emergency stopping method for the rollers of the feeding machine of a forage harvester, including compaction and transportation of plant mass with a pair of rollers, uninterrupted torque measurement to the roller drive, generation of a control signal, activation of the drive shaft brake and shutdown of the roller drive, characterized in that in order to increase reliability by preventing the ingress of foreign objects, mainly stones, into the combine's chopper, analyze the control signal in terms of duration and frequency, asc. The pulse signal of the increment of torque on the drive of the rollers is measured, its amplitude is measured, compared to the allowable threshold, and a command is generated to stop the drive of the rollers from the resulting signal. 2. An emergency stop device for the rollers of the feeding machine of a forage harvester containing a pair of rollers installed with a gap, the upper drum floating and spring loaded, driving a drive shaft connected through a clutch to the engine, a driven shaft brake and a twisting sensor connected to the driven shaft the moment is that, in order to increase reliability by. prevent foreign objects from entering, it is equipped with an electronic unit containing an intermediate frequency filter, a comparator and threshold adjuster, the first input of the comparator is connected to the output of the torque sensor through an intermediate frequency filter, the second input of the comparator is connected to the threshold adjuster, and its output is with the driven shaft brake.