DE102019103119A1 - Overflow valve for closing and opening a fluid line system - Google Patents

Abstract

The present invention relates to an overflow valve (10) for closing and opening a fluid line system (45), comprising a line system (26) running through the overflow valve (10) with a first line section (28) which has a first fluidic connection to a fluid reservoir (36). and a second line section (30) which provides the fluidic connection to a container valve (43) and a throttle (66) arranged in the line system (26) of the overflow valve (10) for throttling the fluid flowing through the line system (26).

Description

The present invention relates to an overflow valve for closing and opening a fluid line system.

A spill valve on which the present invention is based is in the DE 10 2016 115 360 A1 described. Further overflow valves are in the DE 39 02 616 A1 , of the US 2015 0192 213 A1 and the JP 2014 214 804 A described.

A large number of technical applications require a fluid that is under a certain pressure. Particularly relevant technical applications are gas-powered vehicles that run on LPG, natural gas or hydrogen, for example. The pressurized fluid is stored in a fluid reservoir, in particular in a pressure tank. Depending on the application, the pressure at which the fluid is stored in the pressure tank is up to 325 bar for compressed natural gas (CNG) and up to 700 bar for hydrogen. Via a suitably designed fluid line system, which can include pressure lines, the fluid is fed to a number of components that can be pressurized, in particular to the internal combustion engine, where the chemical energy stored in the fluid is converted into mechanical energy with which the vehicle is operated . On its way into the internal combustion engine, the fluid can flow through other components, for example container valves, pressure reducers and inlet valves. Refueling devices that operate in this way are in the JP 2005 221 049 A and the FR 2 935 774 A1 described.

A particular danger arises from an impermissibly high mass flow, for example as a result of a line break in the fluid line system or as a result of damage to components connected to the fluid line system. In this case, a connection to the environment under atmospheric pressure is created, so that suddenly a very large pressure difference arises, which leads to an uncontrolled outflow of the fluid from the fluid reservoir. This leakage can lead, among other things, to explosions or fires, which can endanger people in the vicinity of the torn off pipe.

In order to prevent the uncontrolled outflow of fluid from the fluid reservoir in the event of a line break, overflow valves are used. The overflow valves often protrude into the fluid reservoir or directly adjoin the fluid reservoir and are in fluid communication with the container valve. In many cases, the overflow valve and the container valve are screwed together. Consequently, the container valve is arranged between the overflow valve and the other components that are connected to the fluid line system, for example the internal combustion engine. The line system runs through the overflow valve and is in fluid communication with the fluid line system which is arranged outside the overflow valve. The fluid must flow through this line system both when filling the fluid reservoir and when flowing out of the fluid reservoir. Furthermore, the overflow valve has a valve seat which interacts with a movable closing element. Depending on the position, the closing element closes the line system or releases it. Due to the arrangement of the overflow valve on the fluid reservoir, the pressure of the fluid in the fluid reservoir is applied to the end of the overflow valve with which it is connected to the fluid reservoir, hereinafter referred to as the first pressure.

The closing element is designed such that the second pressure is applied to the end which is connected to the components to which the fluid can act. Due to pressure losses when flowing through the pressure lines and / or due to pressure reductions intentionally carried out outside the overflow valve, there may be a pressure difference between the first pressure and the second pressure. In normal operation, the maximum value of the pressure difference that occurs, hereinafter referred to as the threshold value, is known. The overflow valves are designed in such a way that they release the line system as long as the pressure difference does not exceed the threshold value. Typical threshold values for the pressure difference in the overflow valve are, depending on the design, between 1 and 10 bar, 1 to 5 bar or 2 and 3 bar, these threshold values being heavily dependent on the flow behavior of the fluid as it flows through the fluid line system.

In the above-described case of a line break, the pressure difference between the first and the second pressure assumes values that are well above the threshold value. In this case, the overflow valve closes the line system so that the fluid is prevented from flowing out of the fluid reservoir into the environment. However, since a line break can be an indication of an accident, in particular of the gas-powered vehicle, the fluid in the fluid reservoir under the first pressure can pose an additional risk, for example in that the fluid reservoir is damaged as a result of an impact. The overflow valve can therefore be designed in such a way that when the shooting element is in the closed position, the fluid from the fluid reservoir is nonetheless can flow out. For this purpose, the closing element can have a channel which accordingly establishes the fluid communication. The cross-section of the channel is, however, chosen so that only a small mass flow can pass through the channel. This ensures that the fluid exits the fluid reservoir in a controlled manner over a certain period of time. The dangers emanating from a sudden emptying of the fluid reservoir are thereby prevented.

However, it can also be that the overflow valve is triggered by events other than a line break, for example in the event of a system flooding after maintenance work or in special conditions during normal operation. In this case, pressure equalization is established between the fluid reservoir and the fluid line system via the channel, with the overflow valve automatically opening again completely when the pressure difference falls below a certain threshold value.

In the event that the fluid reservoir is to be refilled with the fluid, the flow through the overflow valve is in the opposite direction. A fluid source, for example at a gas station, holds the fluid at the appropriate pressure. Since the first pressure in the fluid reservoir falls as the degree of filling decreases and the higher pressure of the fluid source is applied on the side facing away from the fluid reservoir, the pressure difference between the first pressure and the second pressure assumes negative values. As a result, the firing element is opened or remains open, whereby the fluid flows from the fluid source into the fluid reservoir.

In order to keep the filling process as short as possible, efforts are made to use the highest possible mass flows. When the fluid flows from the fluid source into the fluid reservoir, the fluid must flow through sections with reduced cross-sectional areas which are arranged within the components and in particular within the container valve and which act as throttles. This leads to a significant drop in the temperature of the fluid, as a result of which the temperature, in particular of the entire container valve, also drops. As a result, seals can suffer a loss of elasticity and therefore temporarily lose their sealing effect, so that the fluid can get into the vicinity of the container valve in an uncontrolled manner. The leaked fluid can pollute the environment and pose a risk of explosion. In addition, the loss of the fluid is undesirable from an economic point of view.

The object of one embodiment of the present invention is to create an overflow valve which acts on the temperature of the container valve in such a way that it falls less sharply than known overflow valves, especially during filling. In addition, it is an object of the present invention to create a component arrangement with which the temperature of the container valve, in particular during filling, falls less sharply than known component arrangements.

This object is achieved with the features specified in claims 1 and 13. Advantageous embodiments are the subject of the subclaims.

• - ein das Überströmventil durchlaufendes Leitungssystem mit einem ersten Ende und einem zweiten Ende, wobei
• - das Leitungssystem über das erste Ende direkt oder unter Zwischenschaltung eines Teils des Fluidleitungssystems mit einem Fluidreservoir fluidisch verbindbar ist, in welchem ein Fluid gelagert werden kann, und
• - das Leitungssystem über das zweite Ende (34) direkt oder unter Zwischenschaltung eines Teils des Fluidleitungssystems mit einem Behälterventil fluidisch verbindbar ist,
• - einen Ventilsitz, wobei
• - das Leitungssystem einen ersten Leitungsabschnitt, der eine erste fluidische Verbindung zum Fluidreservoir bereitstellt, und einen zweiten Leitungsabschnitt aufweist, der die fluidische Verbindung zum Behälterventil bereitstellt und der erste Leitungsabschnitt und der zweite Leitungsabschnitt am Ventilsitz ineinander übergehen, und
• - ein erstes Schließelement, welches zwischen einer ersten Schließstellung, in welcher das erste Schließelement mit dem Ventilsitz zur Anlage kommt und die fluidische Verbindung zwischen dem ersten Leitungsabschnitt und dem zweiten Leitungsabschnitt trennt, und einer ersten Offenstellung, in welcher das erste Schließelement die fluidische Verbindung zwischen dem ersten Leitungsabschnitt und dem zweiten Leitungsabschnitt freigibt, bewegbar ist, wobei
• - im Leitungssystem des Überströmventils eine zumindest Drossel zum Drosseln des das Leitungssystem durchströmenden Fluids angeordnet ist.

One embodiment of the invention relates to an overflow valve for closing and opening a fluid line system, comprising

• - A line system running through the overflow valve with a first end and a second end, wherein
• the line system can be fluidically connected via the first end directly or with the interposition of part of the fluid line system to a fluid reservoir in which a fluid can be stored, and
• - the pipe system via the second end ( 34 ) can be fluidically connected to a container valve directly or with the interposition of a part of the fluid line system,
• - a valve seat, where
• the line system has a first line section which provides a first fluidic connection to the fluid reservoir, and a second line section which provides the fluidic connection to the container valve and the first line section and the second line section merge at the valve seat, and
• - A first closing element, which between a first closing position, in which the first closing element comes into contact with the valve seat and separates the fluidic connection between the first line section and the second line section, and a first open position, in which the first closing element the fluidic connection between releases the first line section and the second line section, is movable, wherein
• - In the line system of the overflow valve, at least one throttle for throttling the fluid flowing through the line system is arranged.

As mentioned at the beginning, the aim is to use the highest possible mass flow when filling the fluid reservoir in order to keep the time for the filling process short. Within the Fluid line system there are sections with reduced cross-sectional areas which act as throttles, but which are not primarily designed as throttles.

According to the proposal, at least one throttle is arranged in the line system of the overflow valve. The throttle is designed in such a way that the throttling of the fluid takes place exclusively or almost exclusively in the overflow valve, especially during filling. For the most part, the temperature of the fluid falls in the throttle. According to the proposal, the greater drop in the temperature of the fluid is relocated to a point, here in the overflow valve, which is determined by the arrangement of the throttle. The temperature of the other components that are connected to the fluid line system, in particular of the container valve, therefore drops to a significantly smaller extent during filling. The above-mentioned temporary loss of elasticity of the seals, in particular of the container valve, is avoided, so that the risk of leaks caused by this is significantly reduced in comparison to conventional overflow valves.

• - weist das Leitungssystem einen dritten Leitungsabschnitt auf, der eine zweite fluidische Verbindung zum Fluidreservoir bereitstellt und in den ersten Leitungsabschnitt oder den zweiten Leitungsabschnitt mündet, wobei
• - ein zweites Schließelement zwischen einer zweiten Schließstellung, in welcher das zweite Schließelement den dritten Leitungsabschnitt verschließt, und einer zweiten Offenstellung, in welcher das zweite Schließelement den dritten Leitungsabschnitt freigibt, bewegbar ist, und
• - die Drossel im dritten Leitungsabschnitt zum Drosseln des den dritte Leitungsabschnitt durchströmenden Fluids angeordnet ist.

According to a further developed embodiment

• the line system has a third line section which provides a second fluidic connection to the fluid reservoir and opens into the first line section or the second line section, wherein
• a second closing element can be moved between a second closed position, in which the second closing element closes the third line section, and a second open position, in which the second closing element releases the third line section, and
• the throttle is arranged in the third line section for throttling the fluid flowing through the third line section.

The third line section provides a second fluidic connection to the fluid reservoir, the third line section only being flowed through when filling. According to the proposal, the drop in the temperature in the third line section has hardly any effect on the temperature of the other components connected to the fluid line system, and in particular of the container valve. In particular, the temperature of the seals hardly drops, so that the above-mentioned leaks due to a temporary loss of elasticity are avoided.

As mentioned at the beginning, the overflow valve is blocked if there is a line break and the pressure difference thus exceeds the threshold value. In this regard, the proposed arrangement of the throttle in the third line section is of further importance because the throttle is not flowed through during normal withdrawal of fluid from the fluid reservoir. If the flow would also flow through the throttle during normal extraction operation, the threshold value of the pressure difference required to block the overflow valve would be increased, so that a defined triggering cannot be ensured and false triggering can occur. However, since there is no flow through the throttle during withdrawal, the pressure difference required for triggering is not influenced.

According to a further embodiment, the overflow valve has a housing with a housing wall, the throttle being designed as at least one bore that runs through the housing wall. In this embodiment, the throttle can be easily manufactured from a manufacturing point of view. In addition, the resulting cold can be dissipated well to the environment via the housing wall, so that the drop in the temperature of the overflow valve can be limited to an uncritical level.

Die kleinste Querschnittsfläche liegt idealerweise außerhalb des Überströmventils und beschreibt die kleinste Querschnittsfläche des gesamten Fluidleitungssystems mit Ausnahme der Drosselquerschnittfläche.In a further developed embodiment, the throttle can have a throttle cross-sectional area and the rest of the fluid line system can have a smallest cross-sectional area and the smallest cross-sectional area can be arranged so that the fluid flows through both the throttle cross-sectional area and the smallest cross-sectional area when flowing from the components through the third line section into the fluid reservoir. The following can apply to the ratio of the throttle cross-sectional area to the smallest cross-sectional area: $$\frac{A_D}{A_k}\le \frac{1}{2}$$

The smallest cross-sectional area is ideally outside the overflow valve and describes the smallest cross-sectional area of the entire fluid line system with the exception of the throttle cross-sectional area.

It has been found that the drop in the temperature of the fluid with this ratio can be concentrated on the throttle in such a way that the remaining components and in particular the seals of the container valve are not cooled down beyond a critical level. In principle, the ratio can be chosen to be as small as possible, with ratios between 1: 2 and 1:10 having proven to be practicable, particularly in the endeavor to limit the time required to fill the fluid reservoir to an acceptable level.

In a further developed embodiment, the first line section can run at least partially inside the first closing element and the first closing element can have a number of first bores, via which the first line section is in fluid communication with a cavity surrounding the first closing element.

In a further embodiment, the second closing element can be designed as a sleeve that is movably arranged in the cavity. In these two embodiments, the overflow valve can be designed to be particularly compact, so that it only requires a small amount of space.

A further developed embodiment is characterized in that the sleeve and the first closing element subdivide the cavity into a first sub-section and a second sub-section, the first bores being in fluid communication with the first sub-section. In this embodiment, too, the overflow valve can be designed to be particularly compact, so that it only requires a small amount of space.

According to a further embodiment, the first closing element has a number of second bores which are in fluid communication with the second subsection. In an alternative embodiment, the housing wall has a number of second bores which are in fluid communication with the second subsection and can be fluidically connected to the fluid reservoir. Because of the fluid communication, the first pressure that is also present in the fluid reservoir is at least essentially always present in the second subsection. There can be no pressure differences in the second subsection which can undesirably influence and change the selected threshold values. The volume of the second subsection changes depending on the state of the overflow valve. Because of the second bores, it is avoided that the fluid in the second subsection is compressed or relaxed when changing the overflow valve between the operating states, whereby the threshold values can likewise be influenced in an undesirable manner.

In a further embodiment, the valve seat is formed by the housing in which the second line section runs. Depending on the mechanical stress, the overflow valve can have a valve body which is separated from the housing and which forms the valve seat. The material of the valve body can be selected according to the demands. However, this complicates the structure of the overflow valve. If the housing forms the valve seat, a separate valve body can be dispensed with, which simplifies the design and manufacture of the overflow valve. In addition, the overflow valve can be provided with compact dimensions. Furthermore, it is not necessary to provide additional pressure lines in order to connect the third line section to the fluid reservoir. The overflow valve according to this embodiment is inserted into the fluid reservoir like a known overflow valve. Additional measures are not required, so that the installation of the proposed overflow valve is not complicated.

In a further developed embodiment, the valve seat is formed by the second closing element, the second line section partially running in the second closing element. In this refinement, the valve seat can remain closed during filling, so that no fluid can flow from the second line section into the first line section if the very low mass flow flowing through the channel is neglected. The entire fluid must flow through the third line section during filling, so that a particularly effective throttling is achieved.

According to a further embodiment, a filter for filtering the fluid is arranged in the first line section. The fluid typically contains particles which can cause damage or malfunctions in the internal combustion engine or the other components, for example. It is therefore advisable to filter the fluid. However, the filter can only be subjected to a limited mass flow without being damaged. Since, in known overflow valves, the path of the fluid during filling and removal are the same and only the direction of flow is reversed, the fluid must pass through the filter both during filling and removal. While the mass flow during removal is very low, efforts are made during filling to achieve a significantly higher mass flow in order to keep the time required for filling as short as possible. The filter therefore sets certain limits on the mass flow during filling. Due to the proposed possibility of using the third line section when filling the fluid reservoir, the filter can be arranged in the first line section so that only a small part of the mass flow flows through it during filling, while the greater part of the fluid is via the third line section flows into the fluid reservoir. Alternatively, the overflow valve can also be designed in such a way that the entire mass flow flows through the third line section during filling. Therefore, the mass flow during filling can be increased and the time required for this shortened without damaging the filter. In this respect, the third line section forms a type of bypass with respect to the filter.

As already explained, during filling the fluid flows almost exclusively into the reservoir via the third line section. When switching from the removal position to the filling position, a fluid impulse flows to the filter, which removes the filter cake that has accumulated in the filter, thereby preventing the filter from blocking.

As mentioned at the beginning, the filter cannot be arranged within known overflow valves, since the installation space available there is not sufficient to make the filter so large that a sufficiently large mass flow can be realized when filling the fluid reservoir. However, since with the proposed overflow valve no or almost no fluid flows through the first line section during filling, the filter can be made so small that it can also be arranged inside the overflow valve. This simplifies the structure of the fluid line system, since no special measures are required for arranging the filter inside the fluid line system and outside the overflow valve.

In a further developed embodiment, the filter comprises a circular filter which can be or is connected to the housing and which serves as a stop for the first closing element. A filter disc refers to a rigid enclosure in which the filter is attached. For example, the filter blank can have a rigid circular ring-shaped section in which the actual filter is held, which extends over the opening enclosed by the circular ring-shaped section. Installation in the overflow valve is simplified because the round filter can be attached to the housing with a flange, for example. Furthermore, the circular section can protrude into the cavity and serve there as a stop for the first closing element, so that no further component is required for the stop.

• 1 ein Überströmventil nach dem Stand der Technik,
• 2 ein erfindungsgemäßes Überströmventil im Normalbetrieb in einer Offenstellung bei der Entnahme,
• 3 das in 2 gezeigte Überströmventil in einer Schließstellung infolge einer Ausnahmesituation,
• 4 das in 2 gezeigte Überströmventil in einer weiteren Offenstellung beim Befüllen, und
• 5 eine Schaltanordnung für das erfindungsgemäße Überströmventil.

Exemplary embodiments of the invention are explained in more detail below with reference to the accompanying drawings. Show it

• 1 a state-of-the-art overflow valve,
• 2 an overflow valve according to the invention in normal operation in an open position during removal,
• 3 this in 2 The overflow valve shown in a closed position due to an exceptional situation,
• 4th this in 2 Overflow valve shown in a further open position when filling, and
• 5 a switching arrangement for the overflow valve according to the invention.

In 1 is an overflow valve 10P according to the prior art shown in a first open position. The overflow valve 10P includes a housing 12th with a housing wall 14th that has a cavity 18th forms in which a first closing element 20th between the first open position ( 1 ) and a first closed position (not shown) along a longitudinal axis L of the overflow valve 10P is movable. In the cavity 18th is a first biasing element 22nd arranged, which the first closing element 20th biases into the first open position. The first closing element is in the first open position 20th at a stop 24 which one with the housing 12th connected is.

The overflow valve also includes 10P on the overflow valve 10P continuous pipe system 26th , which has a first line section 28 and a second conduit section 30th having. The line system 26th has a first end 32 on which from the first line section 28 is formed and over which the pipeline system 26th with a fluid reservoir 36 , for example a pressure tank, is fluidically connected in a manner not shown in detail. In the fluid reservoir 36 a fluid (not shown) can be kept available.

Starting from the first end 32 goes the first line section 28 from an opening 38 of the housing 12th and sits down through a passage 40 of the attack 24 in the first closing element 20th away. The first closing element 20th points in the example shown four radially to the longitudinal axis L running first holes 42 on which the fluid communication between the first line section 28 and the cavity 18th provide. The second line section 30th goes from a valve seat 16 from the second line section 30th from the first line section 28 separates, and sits down to a second end 34 of the pipeline system 26th continue with which the line system 26th by means of a fluid line system arranged outside the overflow valve 45 fluidically with a number of components 44 is connected, which can be acted upon with the fluid. Such components 44 can tank valves 43 , Fluid sources, pressure lines, throttles, internal combustion engines, etc. A basic circuit arrangement is in the 5 shown.

Next to the first closing element 20th has the overflow valve 10P a second closing element 48 on, which in the illustrated embodiment, the already mentioned valve seat 16 forms and with which a third line section 50 of Line system 26th can be closed and opened. The third line section 50 is in the example shown with four or six the housing 12th implemented radially continuous channels in the second line section 30th flow out. But it is also possible to put the channels in the first line section 28 to flow out. The third line section 50 stands with the fluid reservoir 36 in fluid communication.

The second closing element 48 is along the longitudinal axis L in the cavity 18th movable between a second open position and a second closed position. The second closing element 48 acts with a second biasing element 52 together which a closing force on the second closing element 48 applies, whereby the second closing element 48 is moved into the second closed position, in which the second closing element 48 against the housing 12th as in 1 shown. The second closing element closes in the second closed position 48 the third line section 50 .

The first biasing element 22nd and the second biasing element 52 are to a common biasing element 54 summarized. The second closing element 48 is as a sleeve 55 formed, which has a radially extending projection 56 having, with which the second closing element 48 the first closing element 20th encloses. This creates the cavity 18th in a first subsection 57 and a second subsection 58 divided, the common biasing element 54 in the second subsection 58 is arranged. In addition, the second closing element 48 on the first closing element 20th stored. He first subsection 57 and the second subsection 58 are not in fluid communication with each other. In the housing wall 14th are second holes 59 arranged that the fluid communication between the fluid reservoir 36 and the second subsection 58 produce.

In addition, the overflow valve 10P a round filter 60 on in which a filter 62 is attached. The round filter 60 is in the area of the first end 32 of the pipeline system 26th arranged and by means of a flange 64 on the housing 12th attached. The round filter 60 protrudes into the interior of the overflow valve 10P and forms the already mentioned stop 24 for the first closing element 20th in the first open position, so that no additional component is required to provide the stop 24 is needed. In addition, the round filter forms 60 the passage 40 of the first line section 28 .

In the 2 to 4th an embodiment of a proposed overflow valve is shown on the basis of a sectional view. The basic structure of the proposed overflow valve is similar to that of the known overflow valve described above. Also the mode of operation of the proposed overflow valve 10 and its arrangement within the fluid line system 55 corresponds essentially to that of the overflow valve known from the prior art 10P .

The 2 shows the proposed overflow valve 10 in normal operation in an open position, 3 in a closed position as a result of an exceptional situation, and 4th in a further open position when filling.

In contrast to the overflow valve known from the prior art 10P has the proposed overflow valve 10 one in the third line section 50 arranged throttle 66 on, with which the fluid can be throttled when flowing through the third line section. The thrush 66 does not necessarily have to be within the third line section 50 but could also be arranged at a different point within the line system 26th to be ordered. In the illustrated embodiment, the throttle 66 than one in a housing wall 14th of the housing 12th arranged hole 68 executed. The thrush 66 has a throttle cross-sectional area A _D on that compared to the cross-sectional area A ₃ of the third line section 50 of the 1 shown overflow valve 10P is significantly lower.

The proposed overflow valve 10 is operated in the following way: In normal operation, that is, when the pressure difference between the first pressure p1 and the second print p2 is positive and does not exceed a certain threshold value, the common biasing element exercises 54 on the one hand, the already described opening force on the first closing element 20th and on the other hand, a closing force on the second closing element 48 out. As a result, the first closing element 20th into the first open position and the second closing element 48 biased into the second closed position. The fluid can from the fluid reservoir 36 via the first and the second line section 28 , 30th to the components 44 flow, but the third line section 50 from the second closing element 48 is closed. This ensures that the fluid passes through the filter 62 must go through and is therefore filtered.

In contrast to the overflow valve known from the prior art 10P according to the 1 the second hole runs 59 not inside the housing wall 14th , but within the first closing element 20th and opens into the first line section 28 so that the cavity 18th with the second subsection 58 of the cavity 18th is in fluid communication. The second holes 59 ensure that in the second subsection 58 of Cavity 18th same first print p1 prevails as in the first line section 28 and consequently in the first subsection 57 of the cavity 18th .

In the event that the pressure difference between the first pressure p1 and the second print p2 exceeds the threshold value, for example as a result of a line break, the first closing element 20th due to the pressure force acting as well as in the overflow valve known from the prior art 10P against the valve seat 16 moves into the first closed position and closes the line system 26th from (see 3 ).

However, it may be desirable for the fluid reservoir 36 in the event of damage to the pressure line or one or more of the other components 44 to be emptied in a controlled manner, since it is also under the first pressure p1 standing fluid in the fluid reservoir 36 danger can arise. The first closing element provides a controlled emptying 20th a channel 46 on which the fluid communication between the first line section 28 and the second line section 30th is maintained even when the first closing element 20th is in the first closed position. The channel 46 has a compared to the first line section 28 and to the second line section 30th significantly smaller flow cross-section, so that the fluid flows through the channel 46 can only flow through with a correspondingly low mass flow. As a result, the fluid reservoir 36 controlled emptied. If the pressure difference has fallen below a certain threshold during emptying, the overflow valve opens again. The second closing element 48 remains in the second closed position (see 2 ).

When filling the fluid reservoir 36 decreases the pressure difference between the first pressure p1 and the second print p2 a negative value. As a result, the first closing element 20th against the round filter 60 moved to the first open position. As soon as the first closing element 20th is in the open position, the second pressure acts p2 also on the second closing element 48 , which due to the compressive force against the closing force of the common biasing element 54 is moved into the second open position. The fluid flows through the third line section into the fluid reservoir 36 . Although there is over the canal 46 fluid communication between the first conduit section 28 and the second line section 30th , the channel 46 but the diameter is chosen so small that the through the channel 46 flowing mass flow is extremely low and can therefore be neglected.

The main difference to known overflow valves 10P occurs when filling the fluid reservoir 36 on (see 4th ): As mentioned, the fluid flows from the components 44 via the third line section 50 into the fluid reservoir 36 . As also mentioned, the filling should be able to be carried out within the shortest possible time, which is why the mass flow of the fluid is set as high as possible. With reference to 1 one is therefore with known overflow valves 10P endeavors to oppose the fluid with as few flow resistances as possible. Therefore, in the overflow valves described in the prior art 10P the cross-sectional area A ₃ of the third line section 50 at least as large, preferably even larger than the cross-sectional area A ₂ of the second line section 30th .

In contrast, the proposed overflow valve has 10 in the third line section 50 the already mentioned throttle 66 so that the fluid when flowing into the fluid reservoir, that is, when filling the fluid reservoir 36 , is throttled and cooled down in the process. Here is the throttle cross-sectional area A _D chosen so that it is the smallest cross-sectional area through which the fluid has to flow during filling. This ensures that the essential throttling of the fluid in the throttle 66 is carried out.

As explained, the throttling has the effect of lowering the temperature of the fluid in the throttle 66 . But there the throttle 66 in the third line section 50 is arranged, it is ensured on the one hand that there is no throttling in normal operation, that is to say when removing fluid from the fluid reservoir 36 , is made so that there is a sufficiently large pressure difference in the event of a line break, which ensures reliable triggering. On the other hand, the targeted throttling when filling the fluid reservoir 36 in the overflow valve 10 performed. Temperature-sensitive components of the rest with the fluid line system 45 connected components 44 , in particular the seals of the container valve 43 , are only cooled down to an uncritical extent, so that their functionality remains unaffected. As mentioned at the beginning, the overflow valve is 10 at the fluid reservoir 36 arranged and typically protrudes into the fluid reservoir 36 inside. The overflow valve 10 therefore does not itself have any external seals whose functionality could be impaired as a result of the falling temperatures during filling. In addition, the cold resulting from the throttling can be diverted into the fluid reservoir, so that the temperature in the overflow valve 10 can be kept at a relatively high level.

In addition to the throttle cross-sectional area A _D the fluid must flow from the components 44 through the third line section 50 into the fluid reservoir 36 yet another smallest cross-sectional area A _k flow through. The smallest Cross sectional area A _k is apart from the canal 46 the smallest cross-sectional area A _k of the entire fluid line system 45 and the piping system 26th , in this case the cross-sectional area A ₂ of the tank valve 43 which, however, does not necessarily have to be the case. The throttle cross-sectional area A _D is chosen so that its ratio to the smallest cross-sectional area A _k 1: 2 or less, for example 1: 5 or 1:10. It has been found that with this ratio there is sufficient throttling of the fluid when flowing from the components into the fluid reservoir 36 can be achieved to ensure that the fluid is essentially only in the throttle 66 throttled and mainly only cooled there.

In 5 a circuit arrangement is shown based on a basic representation. As mentioned, the overflow valve according to the invention is 10 at the fluid reservoir 36 attached and protrudes into this. The line system 26th passes through the overflow valve 10 . Starting from the fluid reservoir 36 behind the overflow valve 10 is as one of the components 44 the tank valve 43 arranged. The tank valve 43 can either directly with the overflow valve 10 screwed or via part of the fluid line system 45 that is outside the overflow valve 10 is arranged with the overflow valve 10 be connected. From the overflow valve 10 seen from behind the tank valve 43 are additional components 44 , for example an internal combustion engine, via the fluid line system 45 with the fluid reservoir 36 connected. When filling the fluid reservoir 36 becomes the fluid in the throttle 66 throttled so that there, that is, within the overflow valve 10 , the temperature of the fluid is reduced, while the temperature of the fluid outside the overflow valve 10 hardly sinks. Temperature-sensitive parts of the components 44 , especially the seals of the container valve 43 , are spared.

List of reference symbols

10

Overflow valve

10P

Prior art overflow valve

12th

casing

14th

Housing wall

16

Valve seat

18th

cavity

20th

first closing element

22nd

first biasing element

24

attack

26th

Piping system

28

first line section

30th

second line section

32

first end

34

second end

36

Fluid reservoir

38

opening

40

Passage

42

first hole

43

Container valve

44

Components

45

Fluid line system

46

channel

48

second closing element

50

third line section

52

second biasing element

54

common biasing element

55

Sleeve

56

head Start

57

first subsection

58

second subsection

59

second hole

60

Filter blank

62

filter

64

Flanging

66

throttle

68

drilling

A _D

Throttle cross-sectional area

A _k

smallest cross-sectional area

A ₂

Cross-sectional area of the second line section 30th

A ₃

Cross-sectional area of the third line section 50 in the prior art

L.

Longitudinal axis

p1

first print

p2

second print

QUOTES INCLUDED IN THE DESCRIPTION

This list of the documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• DE 102016115360 A1 [0002]
• DE 3902616 A1 [0002]
• US 20150192213 A1 [0002]
• JP 2014214804 A [0002]
• JP 2005221049 A [0003]
• FR 2935774 A1 [0003]

Claims (13)

Overflow valve for closing and opening a fluid line system, comprising - A line system (26) running through the overflow valve (10) and having a first end (32) and a second end (34), wherein - the line system (26) can be fluidically connected via the first end (32) directly or with the interposition of a part of the fluid line system to a fluid reservoir (36) in which a fluid can be stored, and - The line system (26) can be fluidically connected to a container valve (43) via the second end (34) directly or with the interposition of part of the fluid line system (45), - A valve seat (16), wherein - The line system (26) has a first line section (28) which provides a first fluidic connection to the fluid reservoir (36), and a second line section (30) which provides the fluidic connection to the container valve (43) and the first line section (28 ) and the second line section (30) merge into one another at the valve seat (16), and - A first closing element (20), which separates the fluidic connection between the first line section (28) and the second line section (30) between a first closed position in which the first closing element (20) comes into contact with the valve seat (16) , and a first open position in which the first closing element (20) releases the fluidic connection between the first line section (28) and the second line section (30), is movable, wherein - a throttle in the line system (26) of the overflow valve (10) (66) is arranged to throttle the fluid flowing through the line system (26). Overflow valve after Claim 1 , characterized in that - the line system (26) has a third line section (50) which provides a second fluidic connection to the fluid reservoir (36) and opens into the first line section (28) or the second line section (30), and second closing element (48) can be moved between a second closed position, in which the second closing element (48) closes the third line section (50), and a second open position, in which the second closing element (48) releases the third line section (50), wherein - the throttle (66) is arranged in the third line section (50) for throttling the fluid flowing through the third line section (50). Overflow valve after one of the Claims 1 or 2 , characterized in that the overflow valve has a housing (12) with a housing wall (13) and the throttle (66) is designed as at least one bore (68) running through the housing wall (13). Overflow valve according to one of the preceding claims, characterized in that - the throttle (66) has a throttle cross-sectional area (A _D ) and the rest of the fluid line system has a smallest cross-sectional area (A _k ), - the smallest cross-sectional area (A _k ) is arranged such that the Fluid flows through both the throttle cross-sectional area (A _D ) and the smallest cross-sectional area (A _k ) as it flows through the fluid line system into the fluid reservoir (36), and the following applies to the ratio of the throttle cross-sectional area (A _D ) to the smallest cross-sectional area (A _k ) : $$\frac{A_D}{A_k}\le \frac{1}{2}$$

Overflow valve according to one of the preceding claims, characterized in that the first line section (28) runs at least partially within the first closing element (20) and the first closing element (20) has a number of first bores (42) through which the first line section ( 28) is in fluid communication with a cavity (18) surrounding the first closing element (20). Overflow valve after Claim 5 , characterized in that the second closing element (48) is designed as a sleeve (55) which is movably arranged in the cavity (18). Overflow valve after Claim 6 , characterized in that the sleeve (55) and the first closing element (20) divides the cavity (18) into a first sub-section (57) and a second sub-section (58), the first bores (42) being connected to the first sub-section ( 57) are in fluid communication. Overflow valve after Claim 7 , characterized in that the first closing element (20) has a number of second bores (59) which are in fluid communication with the second sub-section (58). Overflow valve after the Claims 3 and 8th , characterized in that the housing wall has a number of second bores (59) which are in fluid communication with the second sub-section (58) and can be fluidically connected to the fluid reservoir (36). Overflow valve after Claim 9 , characterized in that the valve seat (12) from Housing (12) is formed, in which the second line section (30) runs. Overflow valve after one of the Claims 1 to 9 , characterized in that the valve seat (12) is formed by the second closing element (58) and the second line section (30) runs partially in the second closing element (58). Overflow valve according to one of the preceding claims, characterized in that a filter (62) for filtering the fluid is arranged in the first line section (28). Overflow valve after Claim 12 , characterized in that the filter (62) comprises a filter blank (60) which can be or is connected to the housing (12) and serves as a stop (24) for the first closing element (20).

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