DD273359A3 - PRESSURE REGULATOR WITH INTEGRATED SWITCH RELAY - Google Patents

Abstract

The invention relates to compressed air control devices, in particular for motor vehicles. The invention has for its object to design a pressure regulator so that the back pressure of the effluent medium is kept at a relatively low level during the Abstroemvorgang and the switching and Abblasgeraeusche are low while securing a small Druckreglerschaltspanne. According to the invention this is achieved in that in addition to a veraenderlichen axial play a relay piston is provided with stroke limitation. Fig. 1

Description

For this 2 pages drawings

Field of application of the invention

The invention relates to compressed air control devices, in particular in motor vehicles, in which a storage volume is filled with compressed air and in which the otherwise steadily conveyed compressed air is discharged to reduce energy consumption in the atmosphere with reaching a certain pressure levels.

Characteristic of the known state of the art

It is known from DD-PS 141144 a pressure control device in which with filling a memory device at the same time a control piston which is fixedly connected to a valve stem, against oine adjustable arranged compression spring is moved and whereby compressed air is passed to a shut-off when reaching the set pressure levels. The shut-off piston is in turn coupled to an outlet valve, so that after switching off the woiterhin promoted air flow is passed into the atmosphere.

But because the compressor in a motor vehicle very different operating conditions act, i. different pressures, flow rates and compressor speeds are present and the air flow pulsates in itself by the stroke of the compressor, pressure regulator of this type act so that act at certain frequencies or pressures only partial pressures on the shut-off and thus only a partial opening of the exhaust valve. There are relatively high pressure drops on the exhaust valve, whereby the compressor operates in principle against resistance, which has a cost-effective effect on the energy balance. In addition, blown noise caused by this congestion. There are also known pressure regulator, which operate on the principle of differential surfaces. This principle causes large Druckreglerschaltspannen or requires large active surfaces that must be caught by high spring forces wr rden, bt, causes cost-inefficient construction volumes and masses.

Object of the invention

It is the object of the invention to achieve a more economical working catfish by reducing the energy expenditure due to the modified design of the pressure regulator, and to eliminate additional noise disturbances which have hitherto occurred in the event of certain operating conditions.

Explanation of the essence of the invention Dur invention is the object of developing a pressure regulator of the type described above so that he,

regardless of the pressure of the flow or compressed air oscillations always switched so that in the outflow indie atmosphere in the back pressure of the effluent medium is kept at a relatively low level that the switching and

Blow-off noise is relatively low and that the Druckreglerschaltspanne can be kept relatively small. Self-adjusting force equilibrium between control and shut-off piston and between shut-off piston and counter-spring

the sealing cone on the exhaust valve to be disturbed by interposition of relay-like acting components and unambiguously acting force components are converted for the open and closed positions.

Erfindungsgomäß this is achieved by an axially displaceable sleeve is arranged, which seals against the housing

and is pressurized on one side of the seal with supply pressure, on the other side by the pressure of the compressor delivery stream. In the center axis of the sleeve, a seat of a valve double seat is arranged, the second seat of the

Valve double seat is located on the valve stem fixedly connected to the control piston. At the beginning of Schaltvorgangeo, which is initiated by a lifting movement of the control piston on the valve double seat, entstoht

as a result of minor opening or closing of the exhaust valve, a pressure and thus force change on the

Compressor pressure acted upon sleeve side, whereby the sleeve always one opposite to the control piston Performs lifting movement and the switching process or the opening and closing operation on the valve double seat relay-like

supported.

The axial play of the sleeve can be made variable, whereby the size of the pressure regulator range can be influenced The relay-like effect of the sleeve can be achieved by arranging a compression spring between the sleeve and the housing, which is a constant Force exerted on the sleeve in the flow direction of the compressed air, supported or caused exclusively by this

become.

Vibration, opening and closing noises are due to the arrangement of shock-elastic stops frontally between Insulate sleeve and housing. The sealing cone of the outlet valve is additionally a radially sealed, compared to the sealing cone with a larger diameter

provided relay piston fixed or arranged as a loose intermediate piston, which is acted on dor to the sealing cone side facing the pressure of the compressor flow and on the opposite side with atmospheric pressure. The sealing cone is pressed by a spring arranged in the closed position, wherein the closing force by the pending on the relay piston

Compressor pressure is increased and a greater force is caused against the shut-off piston. To open the exhaust valve is thus applied by the shutdown a relatively large force. At the beginning of the opening

creates a minimal pressure drop in the compressor pressure, whereby the forces on the relay piston also si ken and

Excess force em Abschaltkolben to open the sealing cone is formed, which increases in a servo-like manner. To close the exhaust valve is then on the sealing cone to a relatively low spring force, which initially on Shutdown piston the pressure and thus excess power on the double seat valve is so far to reduce until the Druckfeder'den Sealing cone closes easily and forms back pressure in the compressor flow. The dynamic pressure acts in the closing direction

against the remaining power of the shut-off piston on the relay piston, whereby the closing of the

Exhaust valves is sorvoartig amplified. Is the relay piston designed as a loose intermediate piston, the only additional force against the shut-off, but no

directly acting closing force generated on the sealing cone and thus the sealing cone is firmly connected to a smaller piston

Diameter, independently movable in the opening direction, the exhaust valve against an adjustable compression spring also

be arranged as overpressure or safety valve.

When Zusammenw'rken the sleeve movement with the relay piston clear switching functions at the slightest stroke of the Control piston, whereby the friction of the control piston is suppressed, usual, the shift range magnifying Differential surfaces on the control piston, can be kept small who Jf η or virtually absent, so that relatively small Switching margins between switch-off and switch-on pressure can be achieved. Ausführungsbelsplel The invention will be explained with reference to an embodiment. In the accompanying drawings

Figure 1: Pressure regulator with inventive design Figure 2: Inventive execution of a solid relay piston

It shows the following arrangement: In this case, according to Figure 1 in a pressure regulator, the components according to the invention supplemented and executed, arranged such that in Housing 1 adjustable via adjusting screw 2, a control spring 3 is arranged, extending between adjusting screw 2 and Control piston 4 is supported. With control piston 4 is firmly connected valve stem 5, at the bottom of a seat 6 of the Valve double seat angsord iet is. A bore 8 in the valve stem 5 connects SiU β with the control chamber 9, which with the supply air of an operating system

connected is. Valve tappet 5 is radially sealed by seal 10. Below the control piston 4 and the control chamber 9 is

a sleeve 11 with a small axial clearance 12 is arranged. The sleeve 11 centrally receives the zweiton seat 7 of the valve double seat. A Querbo'irung 13 in the sleeve 11 connects the double seat valve 6/7 with the space 14 above the annular Abschaltkolbens 15, which is also disposed in the sleeve 11. By a compression spring 16, a sealing compound 17 is pressed sealingly against the seats 6 and 7.

Sleeve 11 receives a radial seal 18, which sleeve 11 seals against the housing 1 and is suitably designed as a check valve.

The radial seal 18 separates the control chamber 9 from the inflow chamber 19, which is acted upon by compressed air of the compressor. The compressed air flowing from the inflow chamber 19 via the radial seal acting as a return valve into the control chamber 9 is cleaned at the filter 20. The underside of the sleeve 11 is closed by a cover 21 which receives a loose relay piston 22, which is cup-shaped and radially sealed. By the cup-shaped formation ', an upwardly acting stop 23 to the lid 21 and a non-acting bottom stop 24 to the outlet, consisting of a piston 25 smaller diameter, which is radially sealed to the loose relay piston 22, and a sealing cap 26 sealing the outlet Has. Piston 25 and sealing cone 26 are firmly coupled. From below acts against the sealing cone 26, a compression spring 27, which can be made adjustable. The diameter of the loose Relaiskoibens 22 is greater than the diameter of the sealing seat of the sealing cone 26. The arranged in sleeve 11 space 28 is centrally located in the bottom of the shut-off 15, the loose relay piston 22 and the piston 25 through the holes 29,30 and 31 , connected to the atmosphere.

FIG. 2 shows an embodiment according to the invention, in which the loose relay piston 22 is replaced by a part fixedly connected to the sealing cone 26, the reflection piston 32

 The result is the following function:

The compressed air supplied by the compressor passes through inflow chamber 19, radial seal 18 and Steuerkamrr he 9 in the reservoir of an operating system. By increasing pressure, the control piston 4 moves against the control spring 3 upwards. At the same time the rising pressure in the inflow chamber 19 presses the loose relay piston 22 with constantly increasing force against the upward-acting stopper 23. The small pressure difference between the pressures of the inflow and the control chamber inevitably occurring at the radial seal 18 holds the sleeve 11 in the upper position, the axial play 12 is overcome.

After a certain stroke 17 seat 7 is closed in the sleeve 11 and at the same time seat 6 on the valve lifter 5 is released from the sealing element. Reservoir air passes from the control chamber 9 into the chamber 14 via bore 8 and transverse bore 13 and acts on the switch-off piston 15. If the force arising at the switch-off piston 15 is slightly greater than the opposing forces of the loose relay piston 22 and the compression spring 27, switch-off piston 15 moves over the loose actuator Relay piston 22 and 'piston 24 the sealing cone 26 in the opening direction, sealing cone 26 airs a little. This starting leads to a small pressure drop in the inflow chamber 19, whereby a downwardly acting force surplus is produced on sleeve 11 and sleeve 11 moves counter to the direction of movement of the control piston, 4 and the valve stem 5 down. As a result, seat 6 opens clearly. At the same time, the force acting on the loose relay piston 22 force is reduced by the pressure drop in the F.inströmkammer 19, so that the turn-off 15 servo-like significant excess force to open the sealing cone 26 is formed, whereby this is completely opened and no back pressure in the inflow chamber is present.

When pressure drops in the control chamber 9, the control piston 4 moves down. Valve tappet 5 closes seat 6 and ventilates seat 7. The pending on the shut-off piston 15 compressed air is discharged through the transverse bore 13, space 28 and the holes 29,30 and 31 into the atmosphere. When the spring force of the compression spring 27 is slightly larger than the remaining force remaining on the shut-off piston 15, the sealing cone 26 moves upward until the back flow in the inflow chamber 19 is formed. The back pressure acts on the loose relay piston 22 also upwards, whereby the closing force of the compression spring against stopper 15 is servo-like reinforced and sealing cone 26 closes. After ν -eiterem pressure build-up in the inflow chamber 19 moves sleeve 11 because of the resulting low excess force caused by the outgoing from the radial seal 18 effect as a check valve back up, against the direction of movement of the valve stem 5, whereby seat 7 is fully opened.

If the diameter of the piston 25 is slightly smaller than the sealing diameter of the sealing cone 26, an adjustable compression spring 27 can be adjusted so that this system is additionally arranged as an overload or safety valve. Exceeds the pressure acting in the inflow chamber 19 for some reason, a value that is above the normal pressure regulator function, the sealing cone 26 is a downwardly acting force surplus, which 27 the sealing cone 26 against the spring force of the set compression spring. If the axial play 12 between sleeve 11 and housing 1 is made variable, then the stroke of the control piston 4 also changes between the opening and closing operation, whereby the size of the pressure regulator shift range can be influenced and thus is variable. The resulting between the inflow chamber 19 and the control chamber 9 pressure difference, which is used for relay function of the sleeve 11 can be replaced or supplemented by a sleeve 11 and housing 1 axially arranged, not shown in the image compression spring, which on the sleeve 11 in the direction of Control piston 4 acting force exerts. The arrangement shown in Figure 2 of a fixedly connected to the sealing piston 26 relay piston 32 causes the forces of these »relay piston 32 act directly as closing forces on the sealing cone 26.

Claims (5)

1. Pressure regulator with integrated switching relay, preferably for motor vehicles whose compressed air is constantly coming from a compressor via a check valve fills the Vorratsluftbohälter, wherein after reaching a certain pressure level a shut-off piston is acted upon by a double seat valve to control the pressure level in the housing of the pressure regulator with a sleeve radial seal between the housing and sleeve, which simultaneously separates the inflow chamber acted upon by the compressor of the acted upon by the supply pressure control chamber, characterized in that a seat (7) of the double valve seat (6 and 7) as part of the sleeve (11) , between the sleeve (11) and housing (1) for adjusting the required Druckreglerschaltspanne a variable axial clearance (12) that at the outlet of the inflow chamber (19) verschließonden sealing cone (26) a piston (25) fixedly arranged, as well cup-shaped trained, gegenüb he the sealing cone (26) axially movable, the piston (25) in a blind bore, radially sealing, axially movable and in the opening direction of the sealing cone (26) via stop (24) entnehmend, receiving, with a, relative to the sealing cone (26) larger Diameter provided relay piston (22) is provided, wherein on the Roiaiskolben (22) in the closing direction of the sealing cone (26) a stop (23) is provided as a stroke limiter. 2. Pressure regulator according to claim 1, characterized in that instead of the piston (25) with the relay piston (22) with the sealing cone (26) fixedly connected, radially sealed and provided with a, relative to the cone cone larger diameter Reiaiskolben (32), which is acted upon on the side facing the sealing cone (26) with the compressed air of the inflow chamber (19) and on the opposite side with the outside air, is arranged, this relay piston (32) expediently in the sleeve (11). 3. Pressure regulator according to claim 1 or 2, characterized in that axially between the sleeve (11) and the housing (1) a compression spring (33) which on the sleeve (11) in the direction of the control piston (4) exerts a force are arranged can. 4. Pressure regulator according to claim 1 bisa 3, characterized in that the voice side between the sleeve (11) and the housing (1) noise-damping elements are arranged from suitable materials therefor. 5. Pressure regulator according to claim 1, characterized in that the sealing cone (26) in conjunction with the piston (25) and an adjustable compression spring (27) is arranged as a safety valve.