SU1392271A1 - Automatic system for controlling operation of electromagnetic friction clutch - Google Patents

Abstract

The invention relates to mechanical engineering, in particular to devices for transmitting rotation, and can be used to prevent friction electromagnetic overload. couplings with slide valve and circulating lubrication system. The goal is to increase the reliability of the protection of Lrica's young electromagnetic clutch by controlling the specific power of the slip. The system contains the rotational speed sensors for the drive and clutch plates, the reference voltage delay units, the comparator, the OR, AND element, the pressure regulator, and the lubrication control relay. When slipping the friction discs, the determined current specific power of the slip is compared with the critical value specified as a reference voltage signal. When it is exceeded, the clutch is disconnected. The magnitude of the current power density of the skidding is formed by multiplying the clutch power signal, proportional to the moment of friction, and the relative speed signal of the driving and driven disks. 1 il. (L of her QD GCHE N3

Description

one

The invention draws marginos to the structure, in particular to angles. for rotation.

The aim of the invention is to increase the reliability of the coupling sleeves 1.1 by controlling the specific slipping potential. ; The drawing shows block diagrams of an automatic control system for the operation of a friction electromagnetic coupling,

I The system contains a friction-type – disk-type electromagnetic clutch 1 jc spool-pusher 2, ip-ipKy- | lionno lubrication system 3, connected with clutch 1 and containing lubrication control relay 4 and pressure relay 5, element And 6, the delay unit 7, the clutch control unit 8, the drive control unit of the mechanism 9, the rotational speed sensors conduct 10 and the slave 11 drives, the subtraction unit 12, the multiplication unit 13, comparator 14, the reference voltage unit 15, the element OR 16 and winding 17.

In this case, the lubrication control relay 4 is connected to the first input of the drive control unit of the mechanism 9, the second input of which is connected to the output of the element 6 and the output to the input of the control unit of the coupling 8, the second output of which is connected through the delay block 7 to the first input of the element. And 6, and the first output - with the winding 17 of the electromagnetic magnetic coupling 1 and with the first input of the multiplication unit 13, the second input of which is connected to the output of the subtraction unit 12, the inputs of which are connected to the rotational speed sensors of the driving axle 10 and the slave 11 drives. The output of multiplier 13 is connected to the first input of the comparator 14, the second input of which is connected to: the reference voltage unit 15, and the output to the first input of the OR 16 element, the second input of which is connected to the pressure relay 5, and the output to the second the input element And 6,

Automatic control system of the operation of the friction electromagnetic clutch works as follows.

When the lubricating system 3 is turned on} and the coupling 1 is disconnected (spool 2, the pusher 2 closes the channel), the lubricant control 4 of the lubricant 4 and the pressure switch 5 fix the pressure rise. The signal from the relay to} 1 control of lubrication 4 on the possibility of the mechanism working is fed to

1392Z71

the control unit of the drive mechanism 9, and the signal from the pressure switch 5 through the element OR 16 - to the input element AND

6. At the other input of the latter, there is no signal, since when the signal is given to turn on the Koufet 1 from the drive control unit of the mechanism 9

clutch control unit 8 simultaneously outputs a signal to the input of the delay unit

7, which is adjusted to a shutter speed slightly longer than the clutch activation time.

After switching on the coupling 1 (spool, the pusher 2 opens the channel) the pressure in the lubricating system 3 drops and the pressure regulator 5 does not give out God: signal to the element 6, When the signal from the output of the delay unit 7 arrives at the first input of the element 6 its output does not change, since at the second input there is no longer any signal from rels pressure 5, and comparator 14 is not. issuing a signal if there is no slipping of the friction discs. If clutch 1 is not turned on for any reason, then the signal from pressure switch 5 still arrives at the first input of element 6. At the CM, the signal arriving from the delay unit 7 at the first input of element 6 and the last gives a prohibitive signal to the block. control of the drive mechanism 9, which in turn issues a command to the control unit of the sleeve 8 to disconnect the clutch 1.

If the clutch discs 10 and 11 slip when the clutch 1 is turned on, then the signal of the relative angular velocity comes from the output of the subtraction unit 12 to the second input of the multiplication unit 13, the first input of which receives a signal to turn on the coupling from the output of the converting unit 8, proportional contact pressure in the disks 10 and 11, and consequently, the moment tr (nor, since the moment of friction of the electromagnetic clutch is determined by the expression

50

M (f) -t

ET

where K is the moment ratio;

exponent rate;

Magnetic flux;

and

Tj is the time constant of the discharge circuit;

- rated voltage of the winding; W is the number of turns of the winding. Thus, the supply voltage of the coupling 1 is directly proportional to its friction torque. In the multiplication unit 13, by multiplying the voltage of the coupling supply and the signal of the relative angular velocity of the coupling disks, we obtain in accordance with the expression

VA

And (+)

S

where f is relative angle

disk rotation speed; S is the total surface area

training,

the signal is proportional to the specific power of the slippage, which goes to the first input of the comparator 14 and is compared with the signal proportional to the allowable (critical) individual power of the slipping, continuous, power supply; the output of the reference voltage block 15 remains active until , while the specific power of slipping is less than permissible. If the signal at the output of multiplier 13 is equal to or greater than the signal from the output of voltage reference block 15, then at the output of comparator 14 a signal is generated that through the OR element 16 is fed to the first input of the AND 6 element and the last signal prohibits the green signal to the drive control unit Clutch 1 is turned off by clutch control unit 8 when a trip signal is received from the drive control unit of the mechanism.

The use of an automatic system for monitoring the operation of a friction electromagnetic clutch prevents overloading of the friction clutch by slipping power and its premature

Q

five

0

0

five

0

five

wear and tear, resulting in significantly increased reliability of the clutch closure.

Claims (1)

Invention Formula An automatic control system for the operation of a friction electromagnetic clutch, comprising an electromagnetic clutch control unit, a drive control unit, a delay unit, an I element, a pressure regulator and a lubrication control relay, connected to the first input of the drive control unit, the output of which is connected to the electromagnetic control unit input the coupling, the first output of which is connected to the electromagnetic coupling, and the second through the delay unit to the first input of the element I, the output of which is connected to the second input of the control unit Neither actuator, characterized in that in order to increase the reliability of the coupling protection by controlling the specific power of the slip, two rotational speed sensors of the driving and driven disks of the electromagnetic clutch, the subtraction unit, the multiplication unit, the reference voltage unit, the comparator and the OR element are introduced into it , while the rotational speed sensors of the master and slave disks are connected respectively to the non-invertible and invertible inputs of the subtraction unit, the output of which is connected to the first input of the multiplication unit, the second input of which is connected to The first output of the electromagnetic clutch control unit, and the output to the first input of the comparator, to the second input of which the output of the reference voltage block is connected, and the code of the comparator is connected to the first input of the IGO element, to the second input of which the output of the pressure regulator is connected, and the output of the OR element connected to the second input element I. eleven