DE3422705A1 - Pressure-relief valve arrangement for the cooling circuit of a liquid-cooled internal combustion engine - Google Patents

Abstract

The invention proposes a pressure-relief valve arrangement for the cooling circuit of a liquid-cooled internal combustion engine for limiting the pressure during operation of the internal combustion engine and for limiting a comparatively higher pressure after the internal combustion engine has been switched off. This arrangement has a multi-stage pressure-relief valve which, in one stage, opens to the environment at operating pressure and, in a subsequent stage, opens to the environment at the comparatively higher pressure, in each case automatically. This multi-stage pressure-relief valve is integrated directly into a screw-on sealing cover and can be screwed on and off as part of the latter. It simultaneously contains a vacuum relief valve for automatically compensating the vacuum when the coolant cools down. The valve is simple, has only small dimensions and, in a single element that can be screwed directly onto the filler neck of the expansion tank, combines, on the one hand, a pressure-relief valve for limiting the operating pressure and, on the other hand, a pressure-relief valve for limiting the maximum pressure, in order to prevent damage in the cooling system and loss of coolant.

Description

Patent attorney Mülbergerstrasse 65 Authorized representative at Dipl.-Ing. Volkhard Kratzsch D-7300 Esslingen European Patent Office European patent attorney Telephone Stuttgart (0711) 317000 Deutsche Bank Esslingen 210906 cable «krapatent» esslingenneckar Post check office Stuttgart 10004-701

Kühlerfabrik Längerer June 8, 1984

& Reich GmbH & Co KG. . Attorney File 3788

7024 Filderstadt 1

Pressure relief valve device for the cooling circuit

running a liquid-cooled internal combustion engine

The invention relates to a pressure relief valve device for . 5 'the cooling circuit of a liquid-cooled internal combustion engine of the type otherwise defined in the preamble of claim 1.

It is common for the cooling circuit to be a liquid-cooled Secure internal combustion engine so that during operation of the Internal combustion engine, the pressure in the cooling circuit is limited to an operating pressure, this value being lower than that when the internal combustion engine is overheated and at a standstill. You can also see the expansion tank before, which should compensate for changes in the volume of the coolant caused by temperature changes and to avoid coolant ejection with loss of coolant, which occurs after the internal combustion engine has been switched off due to the formation of vapor bubbles can still occur as a result of a heat build-up within the internal combustion engine.

It is a pressure relief valve device of the type mentioned at the beginning known, which has two independent pressure relief valves, which are set to different pressures. The one pressure relief valve that is to limit the operating pressure is set to a lower value than the other pressure relief valve that '25 to avoid damage and loss of coolant on the Maximum pressure is set. Both pressure relief valves are one

EPO COPY

gornüinsüinen valve group combined and on a pipe socket arranged, which is connected to the expansion tank of the cooling circuit. Furthermore, this pressure relief valve device a solenoid valve in the pipeline leading to the operating pressure overpressure valve sits. The solenoid valve is controlled electrically depending on the operation of the internal combustion engine. With running Internal combustion engine, the solenoid valve is controlled so that it is in the open position, so that the Pressure limitation takes place via the overpressure valve provided for limiting the operating pressure. When switching off the internal combustion engine, the solenoid valve is electrically reversed. It now blocks the connection to the operating pressure relief valve, so that now the pressure equalization takes place via the other pressure relief valve, that of the limitation the maximum pressure is used. Such a pressure relief valve device is relatively expensive. It requires two separate separate pressure relief valves with different settings, also the solenoid valve described and also Control lines for connection to the electrical system of the internal combustion engine. These individual components are laborious and expensive. They also have a large footprint. The control device including the Solenoid valve is also quite prone to failure, so that a long-term trouble-free operation is not guaranteed. .

The invention is the. Task is based on a pressure relief valve device to create the genus mentioned in the preamble of claim 1 that is simple and inexpensive is, has small dimensions and ensures a high level of operational reliability.

The task is with a pressure relief valve device The genus defined in the preamble of claim 1 according to the invention solved by the features in the characterizing part of claim 1. Further advantageous measures result from claims 2 and 3.

EPO COPY M

The multi-stage pressure relief valve according to the invention makes it possible to establish a connection to the atmosphere or to a container at several, for example two, different pressures. Although the multi-stage pressure relief valve according to the invention contains only the elements of a single pressure relief valve, it nevertheless enables the multi-stage function, e.g. two-stage function, i.e. in a first stage the pressure limitation to one pressure value, e.g. to operating pressure, and in the subsequent next stage the pressure limitation to an opposite higher pressure value, ·. eg to the maximum pressure when designed as a two-stage valve. With the means of a single pressure relief valve, this double function or multiple function is achieved. The function and automatic switchover from one to the next stage depending on the rate of increase in pressure are important. Only if the pressure increase has a predetermined minimum speed, this automatic switching takes place ^o n the next level. The multi-stage pressure relief valve according to the invention is extremely simple, consists of only a few components, is inexpensive and has only a small footprint, which is practically no larger than that of a single pressure relief valve.

At the same time includes the multi-stage pressure relief valve according to the invention also a vacuum valve in a conventional design for the vacuum equalization during cooling the coolant. It is also advantageous that the multi-stage pressure relief valve according to the invention no additional controls and control lines or the like. needed. This also means that there is a great deal of operational safety given, the risk of malfunctions or failures is averted even with prolonged use. at Integration of the multi-stage pressure relief valve in the cap forms this with the cap a single screw-on and screw-off unit.

EPO COPY

Further advantageous refinements emerge from claims 4 to 24. This means that they are simple, cheap and space-saving means, the individual channels and control surfaces for the multi-stage function, e.g. two-stage function.

Further details and advantages emerge from the following description.

The complete wording of the claims is not given above solely to avoid unnecessary repetition reproduced, but instead only referred to by naming the claim number, which however all of these claim features are to be considered expressly disclosed at this point and as essential to the invention to have. .

The invention is based on one of the drawings illustrated embodiment explained in more detail. It· demonstrate: " - .

· ■ .- ■■

Fig. 1 is a schematic section with partial side view of an expansion tank for which Cooling liquid for liquid-cooled internal combustion engines with screwed on pressure relief valve device,

Fig. 2 is a schematic section of part of the pressure relief valve device along the line H-II in Fig. 1,
-

3 is a schematic perspective view,

partially cut, the guide sleeve of the pressure relief valve device, on a larger scale,
35

4 shows a schematic perspective view of the valve piston of the pressure relief valve device, on a larger scale.

EPOCOPY &

- 41.

The pressure relief valve device shown in the drawings is a liquid-cooled one for the cooling circuit Internal combustion engine and intended for the operation of the internal combustion engine, a pressure limitation to a predetermined Operating pressure, e.g. in the order of magnitude of 0.6 ban and when the internal combustion engine is switched off, a pressure limitation to an increased overpressure, e.g. of the order of 1.2 bar.

The overpressure valve device is formed by a multi-stage overpressure valve, which is designed here as a two-stage overpressure valve 10, which is integrated in an approximately cap-like ^{closure cover 11, which on:} an upper cover part 12 has a cylinder neck 13 'which is integral with it seine'innengewinde 14 on the external thread

, p- 15 of a filler neck 16 is screwed on. The filler neck 16 is firmly and tightly attached to an expansion tank 17, namely where it is above the level in normal operation 18 of the cooling liquid 19 a certain air cushion 20 sets. The expansion tank 17 and also the filling

OQ stubs 16 are made of plastic, for example.

In another exemplary embodiment, not shown, is the filler neck 16 is an integral part of the expansion tank 17. In another exemplary embodiment, not shown is the cap 11 with two-stage pressure relief valve 10 instead on the filler neck of a The collecting tank of the water cooler of an internal combustion engine is screwed on.

OQ The expansion tank 17 is in a conventional manner with the cooling circuit of a liquid-cooled internal combustion engine tied together. The two-stage pressure relief valve 10 is able in a first stage at operating pressure and in addition, if the pressure rises more rapidly in a subsequent second stage, if the pressure is higher than that, i.e. overpressure, e.g. of the order of magnitude over 1.2 bar, each automatically towards the environment or towards one To open the container and thus a connection between this and the Produce expansion tank 17 to reduce the pressure.

EPO COPY di

The two-stage pressure relief valve 10 is either, as shown, with its yet to be described individual elements loosely inserted into the filler neck 16 or not in another shown embodiment held on the cap 11 and attached such that it is unscrewed and unscrewed 5

of the closure cover 11 forms a unit with this.

This training is an advantage, because then a complete _ tes part for screwing on and unscrewing results. The connection

of the elements of the two-stage pressure relief valve 10 on the -, Q locking cover 11 takes place in a conventional manner, e.g. by means of a snap connection or in another form-fitting and / or non-positive manner.

The two-stage pressure relief valve 10 has a cylindrical Guide sleeve 21 within the filler neck 16. Inside the guide sleeve 21 is at least one valve piston 22 added, which is guided up and down in it. The valve piston 22 is designed as a hollow piston. He takes inside a return spring 23, which with one end

_{nn is supported} on the piston head and with the other end on the cover part 12 of the closure cover 11. At the lower end in FIGS. 1 and 3, the guide sleeve 21 carries, preferably in one piece therewith, an inwardly projecting annular collar 24 which forms a valve seat for the valve piston 22.

op- The collar 24 carries a molded sealing ring 25, which is in Cross-section has the shape of an outwardly open lip ring with two sealing lips 26, 27 which form the annular collar 24 encompass. The one sealing lip 26 extends over the valve seat surface of the annular collar 24. The inner surface as well

_on of the annular collar 24 is covered by the molded sealing ring 25. The other sealing lip 27 covers the downwardly facing annular end face 28 of the annular collar 24. There the sealing lip 27 forms a negative pressure compensation element which, when there is negative pressure inside the expansion tank 17, is released from the

"£. Ring face 28 can lift off and in the event of overpressure in the expansion tank is pressed against the ring face 28.

EPO copy m

The valve piston £ 2 is on by means of the return spring 23 the sealing lip 26 pressed on. On its end face 29, the valve piston 22 is with the pressure in the cooling circuit and thus acted upon inside the expansion tank 17.

On its inside, the guide sleeve 21 has several, in the illustrated embodiment a total of six, in equal circumferential angular distances from one another, Axial channels 30 which open out freely at their two axial ends at 31 • and 32, respectively. Here are the axial channels 30 of the guide sleeve 21 between the two ends 31, 32, and here in particular approximately in the area of the middle of the axial length of the guide sleeve 21, closed by means of a circumferential annular web 33 and via this into upper axial channels 30a and divided lower axial channels 30b. The ring web 33 is integral with the guide sleeve 21. Along the length, on which the lower axial channels 30b continue through the annular collar 24 down to the free opening end 32, they are in the form of holes. The free opening lower end 32 is closed by the sealing lip 27 in the over-

pressure operation and is released in the case of negative pressure and lifting sealing lip 27 for negative pressure compensation.

At the upper end in FIG. 1, the guide sleeve 21 has a collar 34 which is integral therewith and protrudes radially outward

on. On its lower side in FIG. 1, this forms a support surface 35 for placing on the free end edge 36 of the filler neck 16 · with the intermediary of a seal 37 to be arranged in between. The collar 34 has an axial channel and a radial channel 38 at the same point,

wherein each radial channel 38 opens out freely with the outer end 39 to the outside and with the end pointing inwards 40 opens into the freely opening end 31 of the respectively associated upper axial channel 30a. The axial channels 30 and Radial channels 38 consist of corresponding grooves. Rib-like are located between the individual axial channels 30 Web 41 with a smooth inner cylindrical guide surface 42 which is aligned with that of the annular web 33.

EPO COPY

The valve piston 22 has on its outer peripheral surface, in the piston wall, also axial channels 52 which communicate with the axial channels 30a, 30b of the guide sleeve 21. These axial channels 52 also consist of axial grooves made in the piston wall. On the perimeter that the

The end face 29 is adjacent, the valve piston 22 has a cylindrical control shoulder 53, via which the axial channels 52 are closed at this lower end in FIGS. 1 and 4. On the other, the end face 29 opposite At the end of the valve piston 22, the axial channels 52 open upwards with their ends 54 there. the Axial channels 52 follow one another in the circumferential direction with such small circumferential angular distances that in each relative rotational position between valve piston 22 and guide sleeve 21. * ·

at least one axial channel 52 of the valve piston 22 in circumferential overlap with an associated upper axial channel 30a and lower axial channel 30b of the guide sleeve 21 is (Fig. 2). As you can see, the axial channels 52 of the Valve piston 22 arranged in the circumferential direction so that the Valve piston 22 on the outside approximately the cross-sectional profile of a Has splined shaft or star profile. The valve piston 22 and the guide sleeve 21 can also, as not is further shown in the circumferential direction over at least

a radial protrusion on one part that turns into an axial 25

channel or an extra recess engages radially on the other part, in a fixed relative rotational position in relation to one another be fixed.

The closure cap 11 carries on the inside of its 30th

Lid part 12 one or more axial projections that Press on the collar 34 of the guide sleeve 21 from above. Individual bars or pins are sufficient here. When shown Embodiment carries the cover part 12 as a projection

an annular ridge 43.
35

EPO COPY

ι On the inside of the cylinder neck 13 are several, e.g. four, placed at equal circumferential angular distances from one another Channels 44 arranged in the form of grooves, which on the free lower edge of the cylinder neck 13 with their local End freely to the outside at the end of 45. In the upper area, the channels 44 are in the vicinity of the upper cover part and of the web 43 via a circumferential, inner annular groove 46 within the cylinder neck 13 in connection with one another. The annular groove 46 runs in the axial region of the collar 34 of the

η guide sleeve 21 and communicates with the radial channels 3Θ, which open with their ends 39 into the annular groove 46.

In the state shown in FIG. 1, the expansion tank 17 has a certain air cushion 20 above the level 18.

This liquid level can be a shutdown internal combustion engine correspond in cold condition. After the internal combustion engine has been started up, the pressure in the expansion tank rises 17 gradually increases as a result of the heating of the cooling liquid 19. If this operating pressure is a certain overpressure,

for example 0.6 bar, overcomes the The force acting on the valve piston 22 is that of the return spring 23. The valve piston 22 is in FIG. 1 upwards raised, the annular edge of the end face 29 lifting from the sealing lip 26 and thus from the valve seat. The one in between formed gap allows a connection of the interior of the expansion tank 17 with the lower Axial channels 30b. These each communicate with at least one associated axial channel 52 of the valve piston 22, which is also above the ring web 33 with the

associated upper axial channels 30a communicate. Since this via the radial channels 38, the annular groove 46 and the channels 44 are in communication with the atmosphere with an open end 45, so is the interior of the expansion tank 17 on the aforementioned individual grooves and channels with the

Connected atmosphere. A further increase in pressure during operation is therefore avoided. Even if now the pressure is gradually increasing

EPO COPY

would rise even further, this position of the valve piston 22 and this pressure limitation would remain as a result of the possible pressure reduction.

After switching off the normally loaded internal combustion engine cools the cooling liquid 19 with an accompanying reduction of pressure. About the return spring 23 is thereby the valve piston 22 is returned to the starting position shown. The one that occurs in the cooling system Underpressure is compensated for by the fact that the sealing lip 27 lifts down from the annular end face 28 in FIG. 1, releasing the opening end 32 of the lower axial channels 30b. As a result, the interior of the expansion tank 17 is in turn connected to the atmosphere, so that the negative pressure compensation can take place.

In certain operating states, especially when operating internal combustion engines in a relatively warm environment, for example tropical countries, it happens that after Ab-. ■ provide a relatively high-temperature, hot-run internal combustion engine due to a heat build-up vapor bubbles form in the internal combustion engine. These cause a very rapid pressure increase in the cooling system and normally an ejection of cooling liquid 19 from the expansion tank 17 with associated losses of cooling liquid 19.. -. -----

This is now through the two-stage pressure relief valve 10 in avoided a single valve element. With such a rapid increase in pressure, the valve piston 22 is against the Force of the return spring 23 initially printed so far in Fig. 1 upwards until the tax paragraph 53 with the cylindrical outer control surface is located at least approximately at the level of the annular web 33 of the guide sleeve 21. In this Position there is a throttled passage. WtMHi uji: h ι Iu r 'oil.iunu-nbüii t / Γ> .Ί iiriil der Ri ri ^ s ti · ^ ΓΚ1 mif ßlciieher Height, the throttling effect is greatest.

EPO COPY

With a further rapid increase in pressure, e.g.

to ■ ·. above a value of 1.2 bar, the valve piston will 22 is shifted even further upward in FIG. 1, its tax paragraph 53 being upward via the annular web 33 in FIG. 1

g migrates out and comes out of overlap with this. Then the inside of the expansion tank is directly above the upper axial channels 30a, radial channels 38, the annular groove 46 and the channels 44 are connected to the atmosphere. Here the axial channels 52 of the valve piston 22 are practical, Q completely inoperative. This second pressure stage is chosen so that damage in the cooling system of the internal combustion engine can be avoided.

The two-stage overpressure valve 10 is simple and stylish, g cheap, at the same time functionally reliable to a high degree, l.-s united in a single component on the one hand a pressure relief valve

for the limitation to the normal operating pressure, e.g. in the range of D, B bar, and on the other hand a pressure relief valve for limiting to maximum pressure, e.g. above 1.2 bar, on the one hand to prevent damage to the cooling system and on the other hand to prevent or as far as possible loss of coolant due to any ejection of this to reduce. . - '

"J- In another exemplary embodiment not shown the multi-stage pressure relief valve not only has two working stages at associated pressures, but also rnuhrerc !. The pressure relief valve then automatically takes one one after the other first, second, third and next following level depending on

_or . the developing pressure conditions and the respective rate of pressure increase. The special advantage of the multi-stage pressure relief valve is that it is automatically dependent on the rate of pressure increase from one stage to the next

"P. transforms. Increases with the illustrated two-stage pressure relief valve 10 the pressure gradually increases, the pressure relief valve 10 goes over to the first stage with pressure limitation this first pressure value. If the pressure is increased, and

EPO COPY

If this is done at a sufficient speed, the pressure relief valve 10 then switches to the next stage associated with this pressure increase speed, with a limitation to this next pressure value. The individual ° valve stages are set automatically depending on certain pressure increase rates.

In another exemplary embodiment, not shown several valve pistons are arranged inside the guide sleeve, e.g. could be. The number of individual valve pistons then corresponds, for example, to that of the possible working stages of the valve. Is the pressure relief valve as a two-stage en-pressure relief valve, the valve IS piston contains a second piston inside, i.e. an inner piston, Axial channels are formed between which and the valve piston. The axial channels are by means of a ring shoulder on the inner piston, which is on a valve seat of the. 'The outer valve piston is seated and by means of the return spring is pressed against it, controllable and releasable to the environment or to the container. The inner piston can be here be designed as a hollow piston whose piston head forms that of the outer valve piston and as Serves abutment for the return spring. Then is located the annular shoulder of the inner piston at an axial distance

from the piston crown. The outer valve piston can be used as an axial

channels in the piston skirt contain axially continuous bores. The end of this that opens out towards the surroundings Bores are then tightly closed by an annular collar of the guide sleeve which is arranged at an axial distance therefrom and provided with a seal, if at a correspondingly high rate of pressure increase at first both pistons are moved together; -be, ir, t, however, in normal operation under gradually increasing operating pressure u ['Fun, whereby Hi buidu Kolhun as uinu unit against the action of the The return spring in the guide sleeve is axially displaced into a stable position Only when there is an increase in pressure a higher value, the outer valve piston together with the inner piston is axially displaced

EPO COPY A

- JLd

1 pushed that the outer mouth ends of the holes

are closed and that then relative to the fixed outer valve piston of the inner piston against the Effect of the return spring releasing the thereby 5 controlled, ■ internal axial channels shifted further will.

EPO COPY.

Claims (1)

Claims MJ overpressure valve device for the cooling circuit of a liquid-cooled internal combustion engine for pressure limitation during operation of the internal combustion engine as well as for limiting a pressure that is higher than that, in particular '; b. with the internal combustion engine switched off, gek ', Β, γ.-η * IK,?, e- ich η et, by ---- one in at least two different' high 'pressure stages depending on the pressure rise' total ' Speed-working multi-stage pressure relief valve (10) which, in one stage at operating pressure and in a subsequent stage at the opposite, preferably rapidly increased pressure, is automatically activated. The surrounding area or opens to a container. 2. Pressure relief valve device according to claim 1, d a d u raw characterized in that the multi-stage pressure relief valve (10) into a filler neck (16) of a compensation tank (17) or a collecting tank of a cooler of the cooling circuit, screw-on cap (11) integrated is. EPO COPY & 3. Pressure relief valve device according to claim 2, d a - ο
characterized in that the multi-stage pressure relief valve (10) is attached to the cap C11D in such a way that it forms a unit with the cap (11) when it is screwed on and off. 4. Pressure relief valve device according to one of the claims 1-3, characterized in that the multi-stage pressure relief valve (10) has a guide sleeve (21) and within the guide sleeve (21) has at least one valve piston (22) guided therein, which by means of a return spring (23) against an annular valve seat of the guide sleeve (21) 'is pressed and can be acted upon on its end face' (29) with the pressure in the cooling circuit. 5. Pressure relief valve device according to claim 4, d a through characterized in that the guide sleeve (21) and / or the valve piston (22) Have axial channels, the inlet of which is controlled by the valve piston (22) on the valve seat and the outlet of which is controlled has a free connection to the environment or to the container. 6. Pressure relief valve device according to claim 5, d a through characterized in that the axial channels (30,30a, 30b) of the guide sleeve (21) and / or those (52) of the valve piston (22) in each case as bores or as axial grooves within the wall the guide sleeve (21) or the valve piston '(22) are formed. EPO COPY 7. Overpressure valve device according to claim 5 or 6, characterized in that the axial channels of the valve piston "or preferably those (3D, 30a, 30b) of the guide sleeve (21) on both axial ends (31,32) open freely. 8. Pressure relief valve device according to one of the claims 5-7, characterized in that the guide sleeve (21) the axial channels (30,30a, 30b) JO on its inside facing the valve piston (22) and the valve piston (22) has the axial channels (52) on its outside and the axial channels (30,30a, 30b) of the guide sleeve (21) and the valve piston (22) communicate with one another. 9. Pressure relief valve device according to one of the claims 4-8, characterized in that the axial channels (30,30a, 30b) of the guide sleeve (21) in the area between the two ends (31, 32), in particular approximately in the area of the middle of the axial length, the guide sleeve (21) closed by means of a circumferential annular web (33) of the guide sleeve (21) and are divided by these into upper axial channels (30a) and lower axial channels (30b). 10. · Pressure relief valve device according to one of the claims 4-9, characterized in that the valve piston (22) on its end face (29) adjacent peripheral area a cylindrical Has control shoulder (53), via which the axial channels (52) of the valve piston (22) are closed at this end are. EPÖ COPY 11. Pressure relief valve device according to one of claims 5-10, characterized in that that the axial channels (52) at the other end of the valve piston (22) opposite the end face (29) have free axially opening ends (54). 12. Pressure relief valve device according to one of the claims 4-11., Characterized in that the guide sleeve (21) at the upper end, which is the the end bearing the valve seat is opposite, has a radially outwardly projecting collar (34), the one support surface (35) for placing on the free Front edge (36) of the filler neck (16), with the mediation of a seal (37) to be arranged between them, carries. . Overpressure valve device according to claim 12, characterized in that the collar (34) of the guide sleeve (21) each axial channel (30) at the same point a radial channel (3B), in particular special has a radial groove which opens out with its outer end (39) freely to the outside and to the inside pointing end (40) into the free opening end (31) of the respectively assigned axial channel (30a) opens. 14.. Overpressure valve device according to one of claims 4 - 13, d a d u r c h characterized, " that the valve piston (22) and the guide sleeve (21) form-fit with one another in the circumferential direction are coupled that in a relative rotational position between 30th Valve piston (22) and guide sleeve (21) at least in each case one axial channel (52) of the valve piston (22) is in circumferential overlap with an associated upper and / or lower axial channel (30a and 30b) of the guide sleeve (21).
35 EPO COPY 15, pressure relief valve device according to claim 14, characterized in that the valve piston (22) and / or the guide sleeve (21) has at least one radial projection which is used for fixing the relative rotational position between the two engages in an axial groove on the other part. 16. Pressure relief valve device according to one of the claims 4-15, characterized in that the axial channels (52) of the valve piston (22) in Circumferential direction with such small circumferential angular distances successive that in each relative rotational position between valve piston (22) and guide sleeve (21) at least one axial channel (52) of the valve piston (22) in circumferential overlap with an associated upper and / or lower axial channel! (30a and 30b) of the guide sleeve (21). 17 · Pressure relief valve device according to one of the claims · 4-1B, characterized in that the axial channels (52) of the valve piston (22) in the circumferential direction are arranged in such a way that the valve piston (22) has approximately the cross-sectional profile of a multi-spline shaft on the outside or star profile. 19. 'Overpressure valve device according to one of the claims 4 - 17, characterized in that the valve seat consists of one on the guide sleeve (21) arranged, preferably one-piece, inwardly projecting annular collar (24) is formed. 19 .. pressure relief valve device according to claim 18, characterized in that the annular collar (24) carries a molded sealing ring (25) which extends with a sealing lip (26) over the valve seat surface, iPOGOPY also over the inner surface of the collar (24) and with a second sealing lip (27) over the collar (34) remote annular end face (28) covering the axially opening ends (32) of the lower axial channels (30b) of the Führunp.ühülsR (21) extends outward and which forms a negative pressure compensation element with this sealing lip (27). 20. Pressure relief valve device according to one of the claims 4-19, characterized in that the at least one valve piston (22) is a hollow piston is formed and has the return spring (23) inside, which has one end at one Piston part, e.g. on the piston head, and at its other end on the cap (11) is supported. 21. Pressure relief valve device according to one of the claims 4-20, characterized in that the valve piston inside at least one contains further inner piston, between which and the valve piston axial channels are formed, which by means of an annular shoulder on the inner piston, which rests on a valve seat of the valve piston, controllable and . can be released to the environment or to the container. 25th 22. Pressure relief valve device according to one of the claims 1-21, characterized in that that the cap-like closure lid (11) on the inside of its cylinder neck (13) preferably several, at preferably equal circumferential angular distances from one another arranged axial channels (44) which at the free edge of the cylinder neck (13) freely to the outside opening ends (45) and at a distance therefrom, in the vicinity .des upper cover part (12), over a circumferential inner annular groove (46) are connected to each other, which are in the axial area of the collar (34) der'Fleithülse (21) runs and communicates with its radial channels (38). EPO COPY . Overpressure valve device according to one of the claims 1-22, characterized in that the closure cover (11) on the cover part (12) has a or a plurality of axial projections which onto the collar 5 (34) of the guide sleeve (21). . Pressure relief valve device according to claim 23, characterized in that the cover part (12) carries a ring-shaped web (43) as a projection. EPO COPY