SU1473999A1 - Pneumatic booster - Google Patents

Abstract

The invention relates to vehicles equipped with a pneumatic system, and is intended to facilitate the control of vehicles. The purpose of the invention is to simplify the design. The housing 1 contains a stepped piston 2, which forms a hydraulic control 3 and a pneumatic 4 cavity with the walls of the housing 1. When the control pressure of the fluid is applied to the stepped piston 2 and the hollow piston 7, the latter, moving, compresses the spring 14 and communicates the cavity 8 with the cavity 4. The stepped piston 2 and the power rod 5 under the influence of the pressure of compressed air move beyond the load. In the absence of compressed air pressure, this movement is due to the control pressure of the fluid, which in this case increases sharply. 1 il.

Description

The invention relates to vehicles equipped with a pneumatic system, and is intended to facilitate the management of vehicles.

The aim of the invention is to simplify the design of the pneumatic amplifier.

The drawing shows a pneumatic amplifier, General view, section.

The pneumatic amplifier comprises a housing 1, a step piston 2, forming a hydraulic control cavity 3 and a power pneumatic cavity 4 with the walls of the housing 1. The power rod 5 is rigidly connected to the step piston 2. A hollow piston 7 is installed in the additional bore 6 of the housing 1, in the inner cavity 8 which is located control valve 9, preloaded by the spring 10. The valve 9 is able to alternately interact with the seat 11, made on the end wall of the piston 7, and with the seat 12, located on the end wall of the bore 6 body and 1 atmospheric central channel 13 which is connected with the atmosphere. Hollow piston 7 is spring-loaded

14. In the wall of the housing 1 there is a bypass channel 15 connecting the cavity of the bore 6 with the power pneumatic cavity 4. The radial channel 16 connects the internal cavity of the hollow piston 7 through the annular groove 17, the supply channel 18 with a source of compressed air. The hydraulic cavity 3 is in communication with the cavity of the bore 6 through the bore 19 in the cover 20, where the control pressure of the fluid enters through the hole 21.

Pneumatic amplifier operates as follows.

Compressed air from an external source enters through the supply channel 18, the annular groove 17 and the channel 16 into the cavity 8. The control valve 9 is pressed against the seat 11.

In the initial position between the seat 12 and the valve 9 there is a gap, while the power pneumatic cavity 4 through the channel 15, the cavity 6 and the channel 13 is connected with the atmosphere.

Through the hole 21, a control fluid pressure is applied, which acts on the stepped piston 2 from the side of the smaller diameter and on the hollow piston 7. Since the force applied to the power rod 5 is much greater than the compression force of the spring 14, the hollow piston 7 begins to move along with control valve 9. At the beginning of the movement of the hollow piston 7, the valve 9 abuts against the seat 12, thereby separating the cavity 4 with the atmosphere. With further movement of the hollow piston 7, the valve 9 opens from the seat 11 and the compressed air from the cavity 8 enters the cavity 4, while the stepped piston 2 moves. 2 together with the power rod 5, overcoming the load applied to it.

With the cessation of the supply of the control fluid pressure to the cavity 3, the spring 14 returns the hollow piston 7 to its original position, while the control valve 9 sits on the seat 11 and disconnects the cavity 8 with the power pneumatic cavity 4. With the further movement of the hollow piston 7, the valve 9 comes off the saddle 12 and cavity 4 through channels 13 and 15 is associated with the atmosphere. Under the influence of the power load applied to the power rod 5, the stepped piston 2 and the power rod 5 return to their original position.

In the intermediate position of the hollow piston 7 and the stepped piston 2, the pressure value of the compressed air in the cavity 4 and the force on the power rod 5 vary depending on the magnitude of the control pressure of the liquid in the cavity 3.

In the absence of compressed air pressure in the cavity 8 (emergency option) after moving the hollow piston 7 all the way to the end of the housing 1, the control fluid pressure in the cavity 3 moves the step piston 2 together with the power rod 5, overcoming the load applied to it. In this case, the value of the control fluid pressure increases sharply.

Claims (1)

Claim A pneumatic amplifier comprising a housing in which there is a stepped power piston with a power rod and a control valve having a control rod in the form of a spring-loaded hollow piston installed in the bore with a radial channel in the side wall and an opening in the end wall and a two-seat valve shut-off element for selective messages bypass channel leading to the power pneumatic cavity, with the inlet channel from a source of compressed air under pressure and with the atmospheric channel, while in the housing a hydraulic cavity for controlling a stepped valve is characterized in that, in order to simplify the design, a bore for the control valve piston is made in the body wall, a two-seat locking element is installed in the valve piston cavity, one valve seat is made on the inner end wall of its piston, and the other in the end wall of the bore, the atmospheric and bypass channels made in the end wall of the bore, the inlet channel is made in the side wall of the bore and is in communication with the radial channel of the piston, and hydraulically the control cavity is formed by the blind end of the valve piston, the walls of the bore, the end of the lower stage of the power piston and the walls of the housing.