SU1551928A1 - Controllable shut-off valve - Google Patents

Abstract

The invention relates to hydraulically controlled valves in hydropneumatic systems that require fast and reliable remote shut-off of the line. The aim of the invention is to increase the reliability of the valve without selecting a working medium for controlling the speed of the valve and increasing its speed. The device provides a shock-free fit of the piston to the valve seat due to negative feedback, which reduces the force exerted by the solenoid on the ferromagnetic shank rigidly connected to the piston as the piston moves toward the valve seat. The negative feedback element is a linear potentiometer 10, the length of the working part 16 of which is equal to the working stroke of the piston 5, and the slider 14 is rigidly fixed on the ferromagnetic shank 13. 1 sludge.

Description

The invention relates to mechanical engineering, in particular to hydraulically controlled valves of hydropneumatic systems in which fast and reliable shut-off of a line is required upon command.

The purpose of the invention is to increase the reliability of the valve without selecting the working medium to control the speed of the valve and increase the speed

The drawing shows a schematic diagram of the hydraulic valve

The controlled shut-off valve consists of body I, two sealed cavities 2 and 3 of which are separated by a spring-loaded (spring 4) piston 5. Two cavities 2 and 7 are formed in cavity 2 and connected to a working line. In cavity 3, an opening 8 is connected. The valve is equipped with a solenoid-type electromagnet 9, a potentiometer 10, a source of 11 EMF and an adjusting resistor 12 The piston 5 is made with a shank 13 connected rigidly to the engine 14 of the potentiometer 10 Winding 15 of the electromagnet 9, engine 14 of the potentiometer 10, Part 16 of the potentiometer 10, the adjusting resistor 12 and the source I I EMF form an electrical circuit of the successors of the 6th switching on of these elements. The working part of the 16 potentiometer 10 is less than the stroke of the piston 5 by

where H - piston stroke 5;

And // - the stroke of the slider 14 of the potentiometer 10 from the initial position before the start of contact with the winding 15;

H is the length of the winding 15 of the potentiometer 10.

Managed shut-off valve operates as follows.

When pressure appears in the control line (in cavity 3), the piston 5, the shank 13, the slider 14 of the potentiometer 10 begin to move, overcoming the rigidity of the spring 4, in the direction of the holes 6 and 7

At the same time, in the area equal to the distance from the initial position before the beginning of the contact of the slider 14 with the working part 16. There is no current in the electric circuit, the speed of movement increases from zero to the maximum value and, and the dynamic state of the system is described by the equation

tx (Rusch. -P) -5 "- / h - (F. + C", -x where t is the mass of moving parts; Ru e is the pressure in the control line; is the pressure in the working line;

/ Vp - friction force, - spring compression force; Se is the piston area; C - piston stiffness

At the moment corresponding to the beginning of the contact of the slider 14 with the working part 16 of the potentiometer 10, a current appears in the electric circuit, the force of which increases as the slider 14 moves along the working part 16 inversely to the reduction of the resistance of the winding 15. An increase in the current in the circuit leads to pointing The electromagnetic field of the electromagnet 9, with the force of the electromagnetic field directed in the direction opposite to the direction of movement of the piston 5 and increases as it approaches the holes 6 and 7;

Mr. Mn-KP-n -S

 CC (x) where F, is the force of the electromagnet; 5 Цо 4л 10 7 Гн / м - magnetic constant; I / - voltage of EMF source; n is the number of turns per unit length

solenoid,

5pcs is the cross-sectional area of the solenoid core;

 - the total resistance of the electric circuit without taking into account the potentiometer winding;

R (x) is the dependence of the change in resistance of the potentiometer on the displacement of the slider; 5x - piston movement.

On the section of the piston 5 from H to H, its dynamic state is described by the equation

(p-p) S "- / V - (ft. + C" -x) - 0io (c-1) UU & "g

% Rt (x) + R,

By accepting the law of variation of the potentiometer linear resistance, one obtains

hell 45M-I,

(- //.) +, ““. (I)

where the magnitude of the minimum resistance of the winding of the potentiometer is selected from the condition of equality of the strength of the electromagnetic field and the sum of the remaining forces acting on the piston 5.

in -V., ipsI-ILUZshg,

 2 | (PW -Р) -5Я-Г „- (Рп„ + С. -х) К (2)

V

and the value of K, KP, "and 11, 55 Equation (1) with regard to equation (2)

where A is the braking coefficient, it is defined as

experienced by every D,, „x - Hi,. I

A, (x) (| (- AO + KJ.

specific case

When the piston 5 is in contact 6 with the orifice 6, the slider 14 comes out of contact with the working part 16 of the potentiometer 10 and the pressure in the control line presses the piston 5 against the orifice 6 with sealing force. The flow of medium along the working line is terminated. When the pressure in the control main is relieved, the spring 4 returns the piston 5 to the initial position.

Using an adjustable resistor 12 provides a change in the current in the electromagnet 9 in order to adjust the speed of movement of the piston 5 in the process of debugging or operation.

Claims (1)

Invention Formula A controlled shut-off valve, comprising a housing with channels for supplying and discharging working medium, a shut-off member made in The form of a piston, the rod of which is connected with a damping device, serving to rot the impact energy of the gate valve with the saddle in the process of operation, with a lenoid mounted on the housing coaxially with the piston of the damping device and forming an electromagnet with the piston rod, characterized in that the goal is to increase the reliability of the valve without selecting the working medium to control the speed of the valve and increase its speed in the solenoid circuit. the element of the damping device included a sliding potentiometer, the slider of which is rigidly connected with the stem shank made of dielectric material, the full stroke of the slider of the potentiometer being equal to the full stroke of the locking member, and the initial portion of the potentiometer is made non-conductive. 0