SU1541569A1 - Device for regulation of gas pressure - Google Patents

Abstract

The invention relates to the field of automatic control and can be used in gas supply systems. The purpose of the invention is to improve the accuracy of regulation in the non-expenditure and low-consumption modes. The device for regulating the gas pressure consists of a body 3 with an inlet and an outlet cavity, two valves and two seats, a sensing element in the form of a stepped piston 14, a force actuator 16, a rod 13, a device 2 for issuing a correction pressure, an elastic element consisting of a radially directional strips fixed on the central part, and a cone-sphere with a rod 13 pivotally connected according to the scheme 13. The device 2 for issuing a corrective pressure comprises a housing 17, a sensing element 19 associated with a driver spring 20 and a valve 21 1 hp f-ly, 3 ill.

Description

2 Issuances Corrective

The invention relates to the field of automatic control and can be used in pneumatic systems for various purposes.

The purpose of the invention is to improve the control accuracy in low-flow and non-expenditure modes. .

FIG. 1 shows the proposed device; in fig. 2 — node I in FIG. one; in fig. 3 shows section A-A in FIG. one.

The device (Fig. 1) contains a reducing unit 1 and a rectifying pressure unit; the unit includes a housing 3 with an input 4 and an output 5 cavities, between which the first seat 6 and the first valve 7c of the first support surface B and the second support surface B are installed, the second seat 8 and the second valve 9 located in the first valve are protruding above the first valve. There is a gap G. and the elastic element 10. The elastic element 1U consists of radially directed strips 11 mounted on a rigid-central part 12 and has a hinged connection | D according to the cone-sphere scheme with a rod 13, transmitting the sensitivity movement of the element 14, made by a stepped piston, forming in its case with its steps a cavity 15 of the corrective pressure. A large piston stage 14 forms a control pressure cavity 16 in the housing, creating a driving force on the piston.

Corrective pressure output unit 2 includes a housing 17, an inlet channel 18 connected to the output cavity 5 of the reducing unit 1, the piston 19 is a sensitive element, connected to the driver spring and a valve 21 having the ability to shut off the saddle 22. The output channel 23 connects the device issuing with a cavity VJ corrective pressure, which

0

five

five

0

5 0 ds

0

five

formed by inflow of medium from cavity 24 through saddle 22 and its outflow through throttle 25.

The device works as follows.

In the initial position, the valves 7.9 and 21 are pressed to their seats, the elastic element 10 contacts the peripheral sections with the second bearing surface B, and between the second valve 9 and the central part 12 of the elastic element 10 there is a gap G.

The driver spring 20 is loaded to a force that balances the output pressure of the piston 19.

With the flow of control pressure into the cavity 16 at the inlet pressure supplied and the shut-off element closed on the output line, the stepped piston 14 through the rod 13 begins to act on the elastic element 10. The bars 11 begin to deform and the central part 12 of the element moves to the gap value G, act on the second valve 9. The medium at the inlet cavity 4 begins to flow in the cavities 5 and 24. When the pressure in the cavity 24 reaches the required value, the piston 19, overcoming the force of the spring 20 of the task, moves, the valve 21 opens the saddle 22 and the medium through the channel 23 enters the cavity. From the pressure of the medium to the annular area of the piston 14, totaling with the force of the output pressure, to the area of the smaller piston stage and some component of the elastic force of the elastic element 10, the piston 14 moves, in the direction of closing the seat 8 by the valve 9D in non-expendable and low-flow modes, the output pressure is maintained by the reaction of the piston 19 on the pressure in the cavity 24, the automatic opening or closing of the saddle 22. Correcting 51Ј

The pressure in the channel 23 is formed by the inflow of the medium through the saddle 22 and the outflow through the throttle 25. By applying this pressure to the piston 14, the opening and closing of the saddle 8 is ensured.

The ideal steady-state adjustment process corresponds to the equality of ai on pistons x 1 and 19 and the equality of inflow of medium through saddle 8 by the consumer, and also of inflow through saddle 22 to outflow through throttle 2i. Real steady-state processes due to such non-linearities as efforts to seal saddles, frictional forces and due to lagging of connections and filling of containers are characterized by periodic displacements of moving parts that are close to discrete.

As a result, without taking additional measures, output pressure fluctuations become especially noticeable in non-expenditure (outflow only through throttle 25) and low flow rates.

In the device in question, the indicated negative effect is significantly reduced by the operation of the elastic element. The stiffness of the element changes the dependence (reduced steepness) of the second valve movement and the flow rate of the medium due to the change in the driving force on piston 1. (The above changes are made automatically and only in low dynamic stability modes - non-expendable and low-expenditure.

The hinged connection D of the rod 13 with the elastic element 10 allows the element to be centered on the rod and self-aligning on the second bearing surface. At the same time, possible intersecting effects on the stock and valve are removed and the conditions for symmetric loading of the strips 11 are created.

96

Claims (2)

1. A device for regulating gas pressure, consisting of a reducing unit comprising a housing, between the inlet and outlet cavities of which a first valve and a seat are installed and installed in the first valve the second seat and the second valve protruding above the first bearing surface, made on the first valve, the sensing element, made in the form of a stepped piston, forming with its steps and body a corrective pressure cavity and connected with one step with the force adjuster, and the other with the stem, connected with the second valve and the first bearing surface of the corrective pressure dispensing unit connected by an inlet with a pneumatic power source and an outlet with a corrective pressure cavity, characterized in that, in order to improve the control accuracy in the low-flow and low-flow conditions, the first valve is made first and between which and the stem is installed with the possibility of limiting the deformation by the first support surface of the elastic element, between which and the second valve in the initial position there is a gap. . 2. A device according to claim 1, about 1 tl, which is characterized by the fact that the elastic element is made in the form of radially directed strips peripherally in contact with the second bearing surface and cantilever connected in a rigid central part that is hingedly connected to the stem. eight Aa