SU1724386A1 - Vibration riddle case - Google Patents

Abstract

Usage: separation of grain mixtures in grain cleaning machines. SUMMARY OF THE INVENTION: A vibrating sieve mill includes a duct 2 mounted on frame 7 by means of elastic couplings 4, an electromagnetic vibration exciter (B) 1, and a control system 3 that is configured with a voltage regulator supplied to B 1 and sets the time and duration for shutdown B 1. To create a braking force between duct 2 and frame 7, the sieve mill is equipped with electromagnetic brakes 5 with a power source 6 and a regulator of the current supplied to them. 1 il.

Description

FIELD OF THE INVENTION The invention relates to agricultural machinery, in particular to grain cleaning machines.

Drives of lattice mills for creating oscillations with the corresponding parameters of amplitude and frequency are known; these are crank, crank, eccentric, and unbalanced mechanisms.

The disadvantages of these drives are: the difficulty of adjusting the oscillation parameters and the high power consumption. This is due to the fact that the amplitude is controlled by changing the eccentricity, or by rearranging the guides for the roller carriage, for which it is necessary to stop the working machine and carry out the appropriate changeover.

The oscillation frequency is controlled by changing the revolutions of the eccentric shaft or by replacing pulleys of different diameters during the transmission of rotation, which also requires additional costs in re-equipment of machines.

A linear drive of a sieve mill of grain cleaning machines is known, comprising a linear motor and an automatic control circuit,

In this electric drive, the linear motor (LD) has two magnetizing coils that control the movement of the moving part of the LD when moving forward and backward. The magnetic system of the LD is constructed in such a way that it provides the required law of motion of the core. The electronic circuit allows you to smoothly adjust the oscillation frequency from 3 to 9 Hz.

In this drive, the disadvantage is that the amplitude of the oscillations remains unchanged, and the frequency control area (3-9) Hz is small.

A vibratory machine is also known, which contains a working body mounted on the frame by means of elastic elements, an electromagnetic vibration exciter of the working body oscillations and a control system for setting the time and duration of the activation of the vibration exciter.

The purpose of the invention is to increase the efficiency of sieving by making it possible to adjust its vibration parameters during operation.

The goal is achieved by the fact that a vibrating sieve mill containing a duct mounted on a frame by means of elastic connections, an electromagnetic vibration exciter of a duct and a seat control for setting the time and duration of activation of the exciter, is additionally supplied with a voltage regulator supplied to the vibration exciter, and electromagnetic brakes with a power source and a regulator of the current supplied to them, mounted on the frame to create a braking force between the duct and the frame.

The drawing shows a vibrating sieve mill.

Vibrating sieve mill consists

0 from an electromagnetic exciter 1, the measles of which is directly connected to the box 2, the automatic control system 3 together with the voltage regulator, the elastic connections 4, the electromagnetic brake 5 for 5, the winding of which is powered from the power source b, and the frame 7.

The camp works as follows. When the electric motor is turned on in an electrical network, the elastic element (spring) is deformed, and a certain amount of energy is stored. After the engine is shut off, the duct, moving back to its original position under the action of elastic forces, makes an oscillatory motion,

5 When the sign of the speed changes again, the motor is connected to the network through an automatic control system and generates a power pulse in tact with a forward stroke. Thus, the lattice mill swings and a self-oscillating regime occurs with a frequency of free oscillations.

f,

m,

where c is the stiffness of the elastic elements; m 5 - the mass of the sieve mill (box).

Change the current of the electromagnetic brake, change the total rigidity (C) of the system, the elastic element - the electromagnetic brake. This adjusts the frequency of St. fluctuations. ,

The amplitude of oscillation of the duct can be adjusted by varying the voltage of the LD in a parametric manner. Moreover, as the stiffness of the elastic elements increases, the amplitude changes in the direction of decreasing, which is required by the conditions of the technological process.

Example. Vibration sieve mill for SMC grain cleaning machine

0 with a linear motor 1 Rtreb 500 watts. self-made leads box 2, electromagnetic brake 5 of the type SE-918 W (4 pcs.), the latter are powered from the U source 6 of power supply 220 V.

5 In the proposed vibratory sieve mill, the use of an electromagnet allows smoothly changing the rigidity of the system an elastic element — an electromagnetic brake, which makes it possible to adjust the parameters of the oscillations.

According to preliminary data, the ability to adjust the vibration parameters of a vibrating sieve mill makes it possible to increase its productivity by 70-100%.

Claims (1)

The invention of the Vibrating sieve mill, including a duct mounted on the frame by means of elastic connections, is an electromagnetic vibration exciter of the duct oscillations and a control system for setting the time and duration of activation vibration exciter, characterized in that, with a chain of increasing the efficiency of sieving by allowing the parameters of the vibration of the box to be controlled during operation, the sieve mill is equipped with a voltage regulator supplied to the vibration exciter and electromagnetic brakes with a power source and a regulator of the current supplied to them, mounted on a frame to create a braking force between the duct and the frame.