SU926630A2 - Pressure regulator - Google Patents

Description

I

The invention relates to power pneumatic automation, and can be used in various pneumatic systems to reduce the pressure of the working medium.

According to the main auth. of- A pressure regulator comprising a housing with an inlet and outlet cavities and a spring-loaded throttling valve installed therein, connected through a pusher to a piston-type sensing element associated with an adjustable spring. The valve seat is designed in the form of a two-stage piston which is spring-loaded in the direction of the sensing element, the lower stage of which is facing the inlet and the larger is towards the outlet cavity m l,

The high static accuracy of the regulator causes a decrease in the stability of its operation and causes self-oscillations of the regulator. In addition, the saddle and the sensing element

The known regulator is loaded with cylindrical springs, the elastic characteristic of which is linear and is characterized by a constant stiffness coefficient. This, in turn, causes a decrease in the control accuracy at low output pressures and the impossibility of using the whole range of compression of the spring of the sensing element and the seat to control the output pressure. The latter limits the operational setting range.

The purpose of the invention is to increase the stability of the regulator to self-oscillations, to increase its accuracy and to expand the range of operating pressures.

This goal is achieved by the fact that the pressure regulator contains a piston, a closed container with a viscous medium, as well as a cup covering it and fixed on a larger stage of a two-stage piston, on the 3 internal surfaces of which there is a sleeve of a ferromagnetic material, and in a closed container fixed On the piston type sensor, a piston is installed, made in the form of a cylindrical permanent magnet with a channel connecting its end cavities in which the choke is located. In addition, the regulator contains additional springs mounted concentrically to the springs associated with the piston type sensing element and the two-stage piston, respectively, and having a length. smaller than specified springs. When the sensitive element and the two-stage piston (seat) oscillates in antiphase (with the automatic regulator mode of the controller), relative movements of the closed container and the cup surrounding it take place. Piston and bushing. magnetic interconnected

No, they do not move relative to each other. This causes a displacement of the pistons in the vessel, in which the viscous medium is squeezed through a channel with a throttle from one end cavity of the container to another and vice versa. At this extrusion, the energy of the oscillation source is expended, the oscillations of the moving parts of the regulator are damped. With synchronous oscillations of the sensing element and the saddle, the piston in a closed container moves under the action, the inertial forces and the dissipation of the oscillation energy also takes place in this case.

When compressing the spring devices (with increasing output pressure), the springs are alternately switched to parallel operation. As the tuning pressure increases, the rigidity of the spring devices increases. In this case, the absolute error of the regulator increases. However, the relative error (the ratio of the absolute error to the adjustment pressure) either remains unchanged or even decreases, which allows for the required control accuracy with an increase in the setting pressure up to the maximum corresponding to the full compression of the spring devices. When the output pressure decreases (decreasing the compression of the spring devices), it alternately emerges with the adjusting screw 13.

A cavity 14 is formed between the steps of the saddle and the body, in which a spring 15 is placed, lifting the saddle k upwards. The end surface of the smaller step of the saddle 4 faces the entrance cavity 2, and the end surface of the larger step is towards the output space 3. The sensitive element can be a membrane one.

Claims (2)

On the sensing element 10, a capacitance 16 is fixed on the side of the output cavity 3 with a medium 17 and a piston 18, made in the form of a cylindrical permanent magnet and dividing the internal cavity of the container into two end cavities 19 and 20, interconnected by a channel 21 with a throttle 22 which can be made both in the piston 18 (as shown in the drawing) and in the wall of the container 16. On the saddle k there is a fixedly mounted cup 23 enclosing a closed container 16, on which is attached a ferromagnetic material sleeve 24, a connected magnet bubbled bonds with the piston 18, which can also be carried out and execution of the sleeve. 24 in the form of a permanent magnet, and the cylinder 18. Of a ferromagnetic material. In both cases, the piston 18 is suspended in the container 16 and occupies the middle position. 0 is excluded from the operation of the spring, the rigidity of the spring devices is reduced, the absolute regulation error is also reduced, the relative error is either reduced, or remains unchanged, but not exceeding the required value. This makes it possible to use during operation for changing pressure settings. The entire range of compression of spring devices, resulting in a significant expansion of the range of operating pressures of the regulator. The figure shows schematically a pressure regulator, a slit. The pressure regulator deletes from housing 1 from inlet 2 and outlet 3 cavities, two-stage piston (seat) if, with channels 5 and 6, loaded with spring 7 of the throttling valve 8, which interacts through piston 9 with piston-type sensitive element 10. Piston 10 loaded with a spring 11, the second end of which, through the plate 12 of the interactions Concentric to the springs 11 and 15, are installed springs 25 and 26 (at least two), respectively, made shorter than springs 11 and 15, which ensures alternate activation of springs 11 and 25, T5 and 26 in parallel operation as the adjusting screw 13 is screwed in. The latter can also be ensured by making the spring support surfaces stepwise. With a slight compression of the springs (when screwing the screw 13 by a small amount), the sensing element 10 and the saddle k are loaded with the springs 11 and 15, respectively. When the tuning pressure increases by the screw 13, the springs 25 and 26 come into contact with the piston 10 and the saddle, respectively t and included in the work. The proposed pressure regulator works as follows. In the initial position, the screw 13 is inserted by a small amount. The spring 11 is compressed, the piston 10 is lowered and rests against the upper edge of the bowl 23, through which the spring force 11 through the piston 10 and the saddle k is transferred to the spring 15, the compression force of which is equal to the spring 11 compression force, the saddle C is also lowered, the spring 15 is compressed. The compression of the spring 11 and 15 is small, and the spring 25 and 2-6 are not included in the work; The throttling valve 8 by the piston 10 through the container 16 and the pusher 9 is pressed from the seat and forms a throttling gap with the latter. The piston 18, being attracted to the sleeve 2, occupies a middle position in the tank 1b. The high pressure gas is supplied through the inlet cavity 2 to the valve 8. In the gap between the valve 8 and the saddle k, the gas is choked and its pressure decreases. Gas lowered. pressure through channels 5 and 6 enters the output cavity 3 of the regulator. The pressure in the exit cavity and its force on the sensing element 10 and the saddle k increase. The piston 10 rises upward, compressing the spring 11, and the saddle k drops downward, compressing the spring 15. This reduces the flow area between the seat C and the valve 8. If the outlet from the regulator is closed, then at a certain pressure in the cavity 3, called pressure settings 06 in statics, valve S overlaps the saddle 4, separating the input and output cavities. When gas is drawn into the volume downstream of the regulator, the pressure and the force of its effect on the piston 10 and the seat t decrease. This leads to lowering the first one down and lifting the second one upwards and, consequently, opening the valve 8 and throttling the gas in the resulting gap between the valve and the seat. The pressure in cavity 3 rises again and for some. Its value between the forces acting on the movable controller system is established by a dynamic equilibrium corresponding to a certain gas flow rate. If the gas flow rate changes, then a new equilibrium occurs at a different value of the throttling gap. When the regulator is unstable, its sensitive elements (piston 10 and seat) oscillate, causing fluctuations in outlet pressure. The most dangerous mode of operation of the regulator is that when the piston 10 and the saddle k oscillate in protypophase, i.e. when the piston 10 rises when it oscillates upwards and the seat then drops down. With this mode of oscillation of the moving parts of the regulator cup 23 with sleeve 2. moving relative to the container 16, and this relative movement consists of the movements of the piston 10 and the seat A. Since the piston 18 is magnetically coupled to the sleeve 2, then when the piston 10 and the seat k oscillate, the (movement) of the piston 18 oscillates relative to tank 16, as a result of which the medium 17 flows through channel 21 with throttle 22 from cavity 19 into cavity 20 of tank 1b and vice versa. At this flow of a viscous medium is consumed (converted into heat) the energy of the source of vibrations. The resulting oscillations of the moving parts are quickly damped. The damping device in the proposed controller provides significantly (almost twice) higher damping capacity, since the oscillation of two sensitive elements is almost the same with the known weight of the damping device. On the other hand, in the proposed controller, piston 18 oscillates in a viscous medium with an amplitude twice as large as the amplitude of oscillations of the inertial heat (piston) of the known device. With oscillations of the piston 10 and the seat in antiphase, which cause fluctuations in the throttling gap, the piston 18 moves in a viscous medium 17 (relative to the capacitance 16) not only under the influence of magnetic forces, but also under the action of inertial forces. Both of these forces add up, having introduced a large amplitude of the 4 4. piston 18. If, for example, piston 10 and seat A are dispensed with, TB sleeve 24, attracts piston 18, then the latter is not down. In the 3ty side, the inertia force is also directed, and vice versa. With synchronous oscillations of the piston 10 and the seat A (when their directions of movement with oscillations coincide), the piston 18 moves relative to the capacitance 16 under the action of inertia. Damping in such oscillations takes place in the proposed pressure regulator. and the adjustment pressure is increased (by screwing in the screw 13) the springs 25 and 2b come into contact, respectively, with the Piston 10 and the seat C, which are included in the work. As the stiffness of the spring devices increases, they can balance the higher output pressure. The upper limit of the tuning pressure increases. The absolute error of the regulator by this also increases, the relative error is either not changed or even reduced. When the output pressure is decreased by relaxing the spring devices, their component springs alternately in 1 point of work, their stiffness coefficients decrease, which is a decrease in the absolute accuracy of the controller and ensuring a constant (or even uMeeHtiioA) function. a bias regulator error that satisfies the requirements for any decrease in the output pressure. A decrease in the lower limit and an increase in the upper limit of regulation of the proposed pressure regulator cause a considerable expansion of the range. on the operating pressure of the regulator. The proposed gas pressure regulator is characterized by high accuracy and stability of operation, which is achieved without noticeably complicating the design and without a perceptible increase in weight. The stability of the regulator to auto-glue allows for a higher reliability of gas supply and an increase in the reliability of the operation of the entire pneumatic system connected to the regulator. The expansion of the range of operating pressures of the regulator creates favorable conditions for the wide unification and standardization of regulators, expands the area of their possible use. Claims. 1. Pressure control according to auth.St. characterized in that, in order to increase the stability of the regulator to self-oscillations, it contains a piston, a closed container with a viscous medium, as well as a cup enclosing it and fixed at a higher stage of the two-stage piston, on the inner surface of which is a ferromagnetic sleeve and in a closed vessel mounted on a piston-type sensitive element, a piston is installed, made in the form of a cylindrical constant mag; nit with a channel connecting its end cavities in which The choke is laid. 2. The regulator according to claim 1, in order to increase the accuracy and expand the range of operating pressure of the regulator, it contains additional springs mounted concentrically with the springs associated with the piston type sensitive element and piston, respectively, and having a length shorter than the specified spring. Sources of information taken into account in the examination, 1. USSR author's certificate, cl. G 05 D 16/10, 1977 (prototype).