DE2738842A1 - OVERFLOW VALVE - Google Patents

Description

R. 4095

August 18, 1977 He / Hm

Robert Bosch GmbH, Stuttgart

via trömventi1

summary

An overflow valve is proposed, the closing part of which is provided on the bottom of a cup-shaped member and which is intended for cooperation with a valve seat fixed to the housing and connected to a compressed air inlet, against which it is pressed under the action of a spring arranged in the cup-shaped member.

The valve seat is formed on an annular body which is inserted into a corresponding expansion of an air inlet duct and is sealed there by a ring seal.

If the overflow valve is to be combined with a check valve, a frustoconical closing body is used attached to the ring body and forms an elastic ring edge of the closing body together with a shoulder the check valve in the air inlet duct.

The overflow valve can preferably be used for compressed air brake systems of motor vehicles; For a four-circuit protection valve, for example, four such overflow valves are required. The check valves then serve to protect the individual brake circuits.

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909812 / OQU

State of the art

The invention is based on an overflow valve according to the preamble of the main claim. Such an overflow valve is known (DT-OS 1 750 822).

This known valve is not suitable for installation

she;

in a housing. In the case of multiple arrangements, such as fz. B. is necessary when used as a multi-circuit protection valve, its aggregation results in a cumbersome, space-wasting structure.

Advantages of the invention

The overflow valve according to the invention with the characterizing features of the main claim has the advantage that its single cartridge, i.e. cup-shaped member and ring body, can be used in many ways. You can at more cost effective Manufactured both as a single overflow valve and as a built-in element in a multi-circuit protection valve be ^ and it can be constructed with or without a check valve. The ring body for a 4-circuit protection valve and for an overflow valve, however, differ in terms of sealing diameter and throttling effect.

By using the ring body, both the valve seat and a throttle gap are not on the housing - which is an expensive one Housing machining would require - but provided on the ring body, whereby the production is simplified. The ring body is an inexpensive die-cast part or injection-molded part that can be finished separately from the housing. To When it is manufactured in series, the ring body is inserted into the housing and fastened there by caulking.

In this way it is possible, if necessary, to fasten the closing body of a check valve on the underside of the annular body, the seat of which is formed on a shoulder of an air inlet duct.

909812/0014

40 0 5

drawing

An embodiment of the invention is shown in the drawing and in more detail in the following description explained. They show: FIG. 1 an overflow valve in section, and FIG. 2 a section through a / ^ Areis protection valve.

description

An overflow valve has a housing 1 which has an inlet 2 with a threaded connection 3 on one side and an outlet 4 with a threaded connection 5 lying on the same axis as the inlet 2 on the other side. To the inlet 2, an air inlet duct 6 connects to a right angle, which is arranged coaxially to a multi-stepped housing bore 7, whose axis is perpendicular to the axis of the inlet 2-outlet ¹ J.

In the air inlet duct 6, a shoulder 8 is provided, which serves as an abutment for an annular body 9. The ring body 9 is a die-cast part or injection-molded part and is finished outside the housing 1. It has on its outer surface an annular groove 10 for fastening the annular body 9 in the housing 1. This is achieved by caulking 13, which - evenly Distributed on the circumference - a housing shoulder 14 is attached at several points.

With its sealing ring 11, the ring body 9 is inserted into an extension 12 of the air inlet duct 6 and onto this Way sealed.

Within the caulking 13, the annular body 9 is provided with an annular valve seat 29. The housing bore 7 receives a pipe section 15 and a cap 16, each with a flange 17 and 18, respectively. The two flanges 17 and 18 are fastened between a bore shoulder 19 and a snap ring in the bore 7.

909812 / OOU

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In the cap l6 is inserted an externally-operable screw 21 with a nut 22, the nut 22 is inserted into the cap 16 is Fogt that they can not rotate. On the inner end of the screw, a spring plate 23 of a spring 2k is placed, which penetrates the pipe section 15 and the other end on a cup-shaped member

25 attacks.

This pot-shaped member 25 is a metal-reinforced plastic part, the one on the edge of the pot with a ring sealing lip

26 is provided with which it is attached to an outer surface of the pipe section 15 is slidably and sealingly attached. A bottom surface of the cup-shaped member 25 is the closing part of the Overflow valve and is intended for cooperation with the valve seat 29 carried by the annular body 9> wherein a throttle gap is formed between the bottom surface and the ring body.

If necessary, as shown, a check valve 27 can be provided within the annular body 9. The check valve 27 has a closing body 28 which is fastened to the ring body 9. The closing body 28 is used for this purpose a frustoconical soft body attached to its small Diameter has an approach 30, with which it is centered in the ring body 9 while leaving coaxial air passage channels 31 is attached. At its large diameter, the closing body 28 has an elastic ring rim 32, which usually rests on the shoulder 8 like a lip.

Mode of action

When the inlet 2 is depressurized, the moving parts of the overflow valve assume the position _o shown in the drawing. If the pressure in inlet 2 is now increased, the check valve 27 opens by lifting the ring rim 32 - * from the shoulder 8. Then the pressure is below the pot

> - »shaped link 25. Depending on the bias of the spring 2Ί set via the screw 21 _o , the overflow valve then opens at a certain pressure level of the inlet pressure in that the cup-shaped member 25 lifts off its valve seat 29. At the beginning of the withdrawal there is a

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Throttling effect for the air passage present in that the existing within the annular valve seat 29 narrow annular surface, a pressure build-up below the surface lying within the valve seat 29 can only reach through with a delay leaves. In the course of the lifting process, the throttling effect is reduced until it is completely lifted off the limb 25 becomes zero.

When the overflow valve is fully open, air can flow through it unhindered; however that remains Check valve 27 always fully effective. If the pressure drops in inlet 2, the overflow valve closes again below the Force of spring 24.

Fig. 2 shows the use of the overflow valve according to the invention in multiple grouping as a multi-circuit protection valve for compressed air brake systems, preferably of motor vehicles. It can be seen that its essentially made up of a closing part, i.e., a cup-shaped member 25, and an annular body 9 existing single cartridge is versatile, e.g. as shown, with a / fe / jfi ^ reis protection valve. One such Valve unit 35 is connected between a compressor and two compressed air reservoirs / and has one of the Number of circuits to be protected corresponding number of overflow valves, which from a certain pressure level the Release the passage of air through the overflow valves and each with a throttle point and a check valve each are equipped. The non-return valves are designed to provide full pressure if the pressure supply fails Maintain pressure in the individual circles. They also serve to secure the individual circles against each other

* ° in the event of a circuit failure, so that the pressure does not arise ο

<o the closing pressure of the overflow valve drops.

^ If necessary, a valve unit can be grouped in multiple ° Can be created by placing relief valves next to and / or

- »can be assembled one behind the other. It is of course too

** possible by omitting a closing body 28 on a To dispense with check valve 27 in an overflow valve.

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Claims (7)

27388A2 R- 40 9 5 August 18, 1977 He / Hm Robert Bosch GmbH, Stuttgart Expectations U Overflow valve, especially for compressed air brake systems of motor vehicles, with a closing body which is provided on the bottom of a cup-shaped member and which is used for cooperation with a valve seat fixed to the housing, connected to a compressed air inlet, against which it is determined is pressed under the action of a spring arranged in the cup-shaped member, characterized in that the Valve seat (29) is formed on an annular body (9) which is in a corresponding extension (12) of an air inlet duct (6) is inserted and sealed there by a sealing ring (11). 2. Overflow valve according to claim 1, characterized in that that the ring body (9) is held in the valve housing (1) by caulking (13). 3. Overflow valve according to claim 1 or 2, characterized in that that the ring body (9) is a die-cast part or injection-molded part. 909812 / OOU -2- 4. Overflow valve according to one of claims 1 to 3, with a check valve, characterized in that a closing body (28) of the check valve (27) on the ring body (9) is attached and that a valve seat of the check valve (27) on a shoulder (8) of the air inlet channel (6) is provided. 5. Overflow valve according to claim 4, characterized in that that the closing body (28) is a frustoconical soft body with an elastic ring rim (32) at its large diameter. 6. Overflow valve according to claim 4 or 5> characterized in that that the frustoconical closing body (28) at its small diameter has a shoulder (30) with which it is fastened centrally in the ring body (9) leaving coaxial air passage channels (31). 7. Overflow valve according to one of claims 1 to 6, characterized in that it is for use as a multi-circuit protection valve for compressed air brake systems in multiple grouping next to and / or one behind the other to form a valve unit (35) is assembled. 909812 / OOU