SU941954A1 - Reduction-type pneumatic valve - Google Patents

Description

The invention relates to pneumatic valves reducing pressure regulation, intended to reduce the gas pressure and maintain it at a constant level and can be used in various pneumatic systems.

A reduction pneumatic valve is known in which the control chamber is divided into two cavities by the sensitive element. The sensing element consists of two membranes, which are fixed to the discs in the center by means of a nut, and on the periphery they are located between the housing, the annular spacer and the cover.

One of the cavities of the control chamber communicates through the throttle opening with the outlet of the pneumatic valve, and the other - with a source of control pressure.

The sensing element controls the throttle valve and the overpressure relief valve. The cf6poca valve inlet is connected to the pneumatic valve outlet through the throttle orifice that supplies the submembrane cavity, and the outlet through the sensing element, the cavity between the membranes and the hole in the annular spacer is connected to the atmosphere 1.

Closest to the present invention, there is a reduction pneumatic valve, comprising a housing with inlet and outlet channels, a lid forming a control chamber with the housing with a sensing element located in it, and a throttle valve connected via the deflector valve 2,

However, for reducing pneumatic valves, the non-unloading of the sensitive element from overpressure is characteristic due to the constant communication of the cavity with the atmosphere, which reduces the reliability and durability of the reducing pneumatic valves.

The presence of moving parts with a large mass (inertia) adversely affects the sensitivity of the pneumatic valve.

The purpose of the invention is to increase reliability.

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Claims (2)

This goal is achieved by the fact that there are holes in the lid of the control chamber and in the sensing element, in which an excess pressure relief valve is placed in the atmosphere-30 fer. In the drawing, the proposed reduction pneumatic valve, longitudinal section. The reduction pneumatic valve contains a housing 1 in which the throttle valve 2 is located. The inlet of the throttle valve 2 is connected to the inlet 3 of the reducing pneumatic valve and the outlet is connected to the outlet of the 4. The submembrane cavity 5 is connected to the outlet of the pressure of the throttle tube 6. Seat 7 of the butterfly valve 2 made directly in the housing 1. For the direction of the throttle valve 2 when it is moved, the spike 8, having a special boring, serves. In the closed position, the throttle valve 2 is clamped to the seat 7 using the force of the spring 9 and the differential pressure of the compressed gas. The pusher is pressed with one 10 end into the throttle valve 2, its second end 11 abuts against the seat 12 of the relief valve 13 and seals it. The shank 14 of the relief valve has a central through hole 15 and passes through the lid 16 of the control chamber 17, The lid 16 has a threaded hole 18 for supplying control pressure to the cavity 19. The sensor 20 uses one membrane 20 fixed to the overpressure relief valve 13 between two discs 21 by means of a nut 22. A reducing pneumatic valve works as follows. When pressure is applied to the cavity 19, the deflection of the membrane 20 causes the pusher 10 to move along with the throttle valve 2. The latter moves away from the seat 7 and through the annular gap formed, the compressed gas from the inlet 3 enters the outlet 4. The outlet pressure acting on the membrane 20 from below through the throttle tube 6 is balanced by the force of the control pressure supplied to the cavity 18. If the outlet pressure 4 falls below a predetermined value (as the flow rate increases), the balance will be broken, the membrane 20 will be propelled to the sides the cavity 5 and the push rod 10 will press the throttle valve 2 by increasing the area of the gas passage and thus pressure at the outlet 4 to the same magnitude. When the pressure at outlet 4 increases (when the flow rate decreases) and at the same time in cavity 5, diaphragm 20 will be propelled toward cavity 19, which will make it possible to move the throttle valve 2. This movement results in the corresponding closing of the throttle valve 2, reduction of the gas flow rate and ultimately , to restore the original pressure. Possible after closing the throttle valve 2, the excess pressure at outlet 4 (for example, due to leakage through the throttle valve 2 in the absence of discharge at the outlet) causes the membrane 20 to be pressed together with the valve 13 for depressurization. In this case, the relief valve 13 opens and compressed gas through the opening 15 in the relief valve 13, the shank 14 of which passes through the cover 16 of the control chamber exits to the atmosphere. Such a reset valve device increases the sensitivity of the reducing pneumatic valve, increases reliability and durability, reduces size and weight, and makes it possible to unify with pressure reducing pneumatic valves with spring loading. Claim I A pressure reducing pneumatic valve comprising a housing with inlet and outlet ducts, a lid forming a control chamber with a sensing element in it and a throttle valve through a tappet associated with a relief valve, characterized in that, in order to improve the reliability of the pneumatic valve, In the control chamber lid and in the sensing element there are holes in which the overpressure relief valve is placed into the atmosphere. Sources of information taken into account in the examination 1. Pneumatic valve type 20AA-8GG. 2. USSR author's certificate number 121294, cl. G 05 D 16/06, 1958 (prototype). 20