SU1252894A1 - Electric drive - Google Patents

Abstract

The invention relates to electrical engineering and is used in a hand-held electroplating tool. The purpose of the invention is to improve the accuracy of stabilization speed. After the transition, the voltage through zero under the action of self-induced EMF through the motor 1 current flows, part of which branches into the measuring chain (IC) 4. The voltage from the voltage W 4 through the amplifier (Y) 5 is fed to the input of the pulse width selector 6. If the pulse duration Y 5 is less than the speed set by the setting device 7, then the feedback circuit does not affect the operation of the electric drive. In case of longer duration of voltage, U 5 starts trigger 8. Introduction of control generator 10, generator of synchronizing pulses 11, decade counter 12, circuit 9 of coincidence with increasing load on the shaft ensures the restoration of a given speed and setting of a quasi-static engine operation mode. 1 il. & O) I ate to 00 4;

Description

This invention relates to electrical engineering and can be used in a hand-held electrofused tool.

The aim of the invention is to improve the speed stabilization accuracy.

The drawing shows the layout of the drive.

The DC electric drive contains an electric motor 1, the main winding of which is connected to a thyristor converter 2 connected to the power source 3, a measuring chain 4 connected to the main winding of the electric motor 1, the output of which is connected to the input of the amplifier 5,

In addition, the electric drive contains a pulse width selector 6 connected in series, one input of which is connected to the output of amplifier 5, and the other to the output of speed reference 7, trigger 8 and coincidence circuit 9, the code of which is connected to the control input of the thyristor converter 2, A control generator 10 is connected to the second input of the coincidence circuit 9, the synchronization pulse generator oscillator 11 is connected to power supply 3, and the output via decade counter 12 is connected to the second trigger input 8 and to control input sch5istornogo transducer 2

The device works as follows.

After the voltage passes through zero, under the action of self-induction EMF, a current flows through motor 1, a part of which branches into measuring chain 4. The constant time of self-induction current for electric motor 1 of sequential excitation depends on the frequency of rotation of its core and electric motor 1 in such a way the decay time of this current and zero with a high degree of accuracy is proportional to the ratio of the motor current to its frequency of rotation

, "-0 -" Tj

where K - kozffits}; the proportionality;

I is the motor electric current; J is the motor speed. The voltage from the output of the measuring chain 4 is amplified by the amplifier 5

five

0 5 0

five

0 5

0

five

and is fed to the input of the pulse width selector 6. If the duration t of the voltage pulse coming from the amplifier 5 is less than the speed set by the t setpoint adjuster 7, then the feedback circuit does not affect the operation of the electric drive. In the case where the input voltage pulse duration exceeds the set time, the time difference is tj trigger 8 is started, which is set to zero by means of a decade counter 12 connected to the output of the generator 11 - synchronizing pulses, the output of the trigger 8 through the coincidence circuit 9, to which the control, the generator 10, is also connected, connected to the input of the thyristor converter 2. With an increase in the load on the shaft of the electric motor 1, the current 1 increases and the speed uj decreases;

tat. what increases about

and, if to exceeds t., then a triggering voltage pulse arrives at the input of trigger 8, which leads to a voltage applied to the electric motor, which will act until the set speed is restored, after which the drive system i will continue its work in quasistatic mode .

Claims (1)

Claims. A DC motor containing a series excitation motor, the main winding of which is connected to a thyristor converter connected to a power source, a measuring chain connected to a corium winding of an electric motor whose output is connected to the amplifier input, a speed gauge that differs from fettf that The aim is to increase the accuracy of speed stabilization, a control generator, a generator with iN pulse impulses, decaJp and I: counter, as well as in series with The pulse duration selector, whose input is connected to the output of the amplifier and the other to the speed master input, triggers a coincidence circuit, the output of which is 1 pin to the control input of the thyristor transducer 3112289Л4 The body is connected to the second input of the coincidence circuit, and the output through the decade counter NIN is connected to the control generator, connected to the second input of the trigger, and the generator input to the synchronous clock qih km is connected to the control input of the thyristor pulses. Compiled by M, Kr Khtunova Editor P. Kossey Tehred V. Kadar Proofreader M. Samborska Order 4629/55 Circulation 631 Subscription VNIIPI USSR State Committee for inventions and discoveries 113035, Moscow, Zh-35, Raushsk iab., d. 4/5 Production and printing company, Uzhgorod, st. Project, 4