EP4105166A1 - Dispensing valve - Google Patents

Abstract

The invention relates to a dispensing valve, comprising an inlet (13) for connecting a fluid supply line, an outlet (14) for dispensing the fluid, a fluid channel (15) connecting the inlet to the outlet, a main valve (16) located in the fluid channel (15). ) which is preloaded against a valve seat in a closed position, a hand lever (17) for actuating the main valve (16), and a clutch device (22) which is operatively connected to the hand lever (17) and which, in the coupled state, is set up to To convert the movement of the hand lever (17) into an actuation of the main valve (16), the main valve (16) being pushed into the closed position in the uncoupled state, independently of the position of the hand lever (17). The dispensing valve also has a membrane (26) which separates a first membrane space (27) from a second membrane space (28) and which, due to a pressure difference existing between the first membrane space (27) and the second membrane space (28), is used to actuate the clutch device (22) is movable. A vacuum can be applied to the first membrane space (27), with a sensor line (19) opening into the first membrane space (27). According to the invention, the second membrane chamber (28) is sealed off from the fluid channel (15) and is fluidically connected via a ventilation channel (29) to an environment outside the dispensing valve, with a part of the coupling device (22) located outside the second membrane chamber (28) when the main valve is open (16) is washed by the fluid. The reliability of the release of the clutch device can be significantly improved in this way.

Description

The subject matter of the invention is a dispensing valve with an inlet for connecting a fluid supply line and an outlet for dispensing a fluid. The inlet is connected to the outlet via a fluid channel, with a main valve being arranged in the fluid channel and being biased into a closed position against a valve seat. The dispensing valve also includes a hand lever for actuating the main valve and a clutch device which is operatively connected to the hand lever and which, in the coupled state, is set up to convert a movement of the hand lever into an actuation of the main valve. In the uncoupled state, the main valve is forced into the closed position, regardless of the position of the hand lever. The dispensing valve also has a membrane which separates a first membrane space from a second membrane space and which can be moved by a pressure difference existing between the first membrane space and the second membrane space to actuate the clutch device, wherein the first membrane space can be acted upon by a vacuum and wherein a Sensor line opens into the first membrane space.

Nozzles of this type are, for example, from the document EP 2 386 520 B1 famous. The sensor line can be routed to a downstream end of an outlet pipe, so that the sensor line is covered and closed by the liquid in the tank at the end of a refueling process. Due to the loading of the first membrane space with a vacuum, the pressure in the first membrane space is reduced by the closing of the sensor line, which leads to a movement of the membrane in the direction of the first membrane space. This movement can be used to actuate the clutch device. By actuating the coupling device, it can into the decoupled state in which the main valve is moved to the closed position regardless of the position of the hand lever. In this way, after the tank has been completely filled, further fluid delivery and thus overflowing of the tank is prevented.

A problem occurring in the state of the art is that, in order to ensure that the clutch device is always released reliably and safely, a great deal of design effort and high maintenance effort must be made.

Against this background, it is the object of the present invention to provide a nozzle of the type mentioned above, in which the release of the clutch device can be realized in a structurally simpler, safer and less maintenance manner.

This problem is solved with the features of the independent claims. Advantageous embodiments are specified in the dependent claims. According to the invention, the second membrane space is sealed off from the fluid channel and fluidly connected via a ventilation channel to an environment outside the dispensing valve, with a part of the coupling device located outside the second membrane space being flushed with fluid when the main valve is open.

First, some terms used within the scope of the invention are explained. The coupling device is set up to convert a movement of the hand lever into an actuation of the main valve in the coupled state. It is not necessary for the coupling device to establish a direct connection between the hand lever and the main valve. Rather, it may be sufficient, for example, that the coupling device for the hand lever with a device Prestressing of the main valve in the closed position couples, so that this prestressing can be compensated or canceled with the help of the hand lever. The main valve can then be moved to the open position by upstream fluid pressure, such as that shown in FIG EP 2 386 520 B1 is known. Alternatively, the coupling device can also be set up to couple the hand lever to a fixed point, which serves as a counter bearing when the hand lever is actuated and enables power transmission to the main valve in the first place, as can be seen, for example, from FIG U.S. 2018/037452 A1 is known. Other clutch devices that are basically known to those skilled in the art and can be actuated by a pressure-sensitive membrane are also included in the concept of the invention.

In prior art dispensing valves, it was common for the space below the diaphragm to communicate with the fluid passage. This has the advantage that the fluid flows around the clutch device connected to the membrane when the main valve is open. In this way, the clutch device is continuously lubricated by the fluid and dirt is flushed away, which is beneficial to the functionality and reduces the maintenance effort.

Within the scope of the invention, however, it was recognized that the connection of the second membrane space to the fluid channel leads to the disadvantage that the pressure below the membrane is influenced by the volume flow of the fluid. In the case of high volume flows or also in the case of flow turbulence and associated pressure peaks, in the prior art this could lead to an undesired actuation of the clutch device and thus to an undesired closing of the main valve. The maximum volume flow therefore had to be limited in the solution known from the prior art.

By contrast, since the second membrane space is sealed off from the fluid channel and is connected to the surrounding fluid via a ventilation channel, the pressure within the second membrane space can be kept constant at the level of the ambient pressure regardless of the volume flow. In this case, when the first diaphragm chamber is subjected to a specified vacuum, the covering of the sensor line leads to a defined pressure difference. The pressure difference between the first and second diaphragm space can thus be controlled much better, so that the clutch device can be actuated in a defined and safe manner. Since it is also provided that a part of the clutch device located outside of the second diaphragm chamber is flushed by the fluid, the fluid can flush and lubricate the clutch device despite the sealing of the second diaphragm chamber, so that the clutch device can be kept running smoothly for long periods of time without additional maintenance effort can be. Regular cleaning or the introduction of additional lubricants is not required.

In a preferred embodiment, the coupling device has a latching element for coupling the hand lever to a valve actuating element. The latching element can preferably be moved into or out of a coupling position by a movement of the membrane. The valve actuating element can, for example, have a first valve stem connected to the hand lever, which can be coupled to a second valve stem by means of the latching element, the second valve stem being prestressed in a closing direction by a restoring element and designed to urge the main valve into the closed position. In the coupled state, the force exerted by the restoring element can be compensated for by means of the hand lever, so that the main valve is no longer forced into the closed position and by one Fluid pressure can be moved to the open position. The first valve stem can be designed as an inner valve stem and the second valve stem can be designed as an outer valve stem, which concentrically surrounds the inner one. The locking element can have locking rollers or locking balls, for example.

It has been shown that the latching element, which couples the hand lever to the valve actuating element, when moving into the latched position or out of the latched position, can strike corners or edges of the elements to be coupled and become wedged in the process. In a preferred embodiment, the latching element is therefore positioned in such a way that the fluid flows around it when the main valve is open. As a result of the continuous lubrication of the locking element made possible in this way when the main valve is open, it can slide more easily into or out of the locking position, so that the coupling process becomes significantly more reliable.

In an advantageous embodiment, the second membrane chamber is sealed off from the fluid channel by means of a cover, with the coupling device preferably having a connecting element connected to the membrane, which is guided in a sliding manner through a through-opening in the cover. The connecting element preferably has a section which is located outside of the second diaphragm chamber and is connected to the latching element. Because the connecting element is slidably guided through the cover, the connecting element can move relative to the cover when the membrane moves, and in this way transfer the movement of the membrane to the latching element. Because the second membrane space is sealed off from the fluid channel, the pressure within the second membrane space is not influenced by the pressure conditions in the fluid channel.

At least one sealing element can be arranged between the connecting element and the cover, which is preferably designed as an O-ring, X-ring, membrane seal or lip seal. The connecting element can have an outwardly pointing circumferential groove into which the sealing element is let. It is also possible for the through-opening of the cover to have an inward-pointing circumferential groove into which the sealing element is embedded. In this way, the entire peripheral surface of the connecting element can be sealed off from the cover. By inserting the sealing element into a groove, it is also reliably protected against displacement along the axial direction of the connecting element.

The use of one or more ventilation ducts, which connect the second membrane space with the environment, is fundamentally associated with the risk that dirt, such as dust particles or liquids, can penetrate into the second membrane space. In an advantageous embodiment, the at least one ventilation channel therefore opens into an opening of the nozzle pointing towards the environment, the opening being covered by a flexible protective cover in such a way that pressure equalization is possible. In addition, the ventilation channel is preferably led to the opening in the manner of a labyrinth. In this way, penetrating dirt particles cannot at least not penetrate directly into the second membrane space, but rather have to change their direction of movement several times in order to approach the membrane space along the labyrinthine channel. This means that dirt can be significantly reduced or even completely prevented.

In an advantageous embodiment, the membrane and the coupling device connected to it are part of a safety shutdown module that is integrated into a housing of the nozzle can be used. The modular design makes it possible to replace the entire safety shutdown module in the event of a malfunction. The use of safety shutdown modules is basically known from the prior art. The safety shutdown module can therefore be configured in principle to be compatible with previously known nozzles, so that the features according to the invention can be retrofitted to a nozzle of the prior art by replacing the safety shutdown module.

In one embodiment, the dispensing valve can also have a shut-off device which moves the main valve into the closed position independently of a position of the hand lever when a liquid pressure at the inlet falls below a minimum value. The switch-off device is therefore triggered when the pressure falls below the minimum, such triggering preferably being accompanied by a movement of the membrane. Such an additional switch-off device is basically state-of-the-art (see e.g EP 2 386 520 ) famous. The shutdown device can be integrated into the safety shutdown module. In a known manner, triggering of the shut-off device leads to the diaphragm moving in the direction of the first diaphragm chamber and thereby releasing the coupling between the main valve and the hand lever (for example by locking rollers being lifted out of a locking position), so that the main valve is pushed into the closed position will. Since the second membrane space is sealed off from the fluid channel according to the invention, a subsequent resetting of the shut-off device, in which the membrane is moved back into the starting position (ie in the direction of the second membrane space), can take place much faster and more reliably. In particular, in the prior art, during the reset movement of the membrane, fluid had to be displaced from the second membrane space through often narrow channels, which was particularly the case in viscous fluids (e.g. when dispensing diesel at low temperatures) could cause problems. On the other hand, due to the sealing of the second diaphragm chamber, fluid displacement is no longer required when resetting, so that the disconnection device can be reliably reset after it has been triggered.

The subject matter of the invention is also a petrol pump with a dispensing hose and a dispensing valve according to the invention, the dispensing hose being connected to the inlet of the dispensing valve. The petrol pump can be further developed by further features described within the scope of the invention.

Figur 1:

ein erfindungsgemäßes Zapfventil in einer seitlichen Schnittansicht;

Figur 2:

einen Ausschnitt aus der Figur 1 in vergrößerter Ansicht;

Figur 3:

das in der Figur 2 gezeigte Sicherheitsabschaltungsmodul in vergrößerter Ansicht;

Figur 4:

das Sicherheitsabschaltungsmodul der Figur 3 in einem anderen Zustand;

Figur 5:

das Sicherheitsabschaltungsmodul der Figur 4 in einer Querschnittsansicht entlang einer anderen Schnittebene;

Figur 5a:

eine Schnittansicht entlang der in Figur 5 eingezeichneten Linie A-A;

Figur 6:

ein Sicherheitsabschaltungsmodul einer alternativen Ausführungsform eines erfindungsgemäßen Zapfventils;

Figur 7:

eine Detailansicht eines Kontaktbereichs zwischen Verbindungselement und Abdeckung zur Illustration einer alternativen Ausführungsform;

Figur 8:

eine Detailansicht eines Kontaktbereichs zwischen Verbindungselement und Abdeckung zur Illustration einer weiteren alternativen Ausführungsform;

Figur 9:

eine Detailansicht eines Kontaktbereichs zwischen Verbindungselement und Abdeckung zur Illustration einer weiteren alternativen Ausführungsform;

Figur 10:

eine Detailansicht eines Kontaktbereichs zwischen Verbindungselement und Abdeckung zur Illustration einer weiteren alternativen Ausführungsform;

Figur 11:

eine Detailansicht eines Kontaktbereichs zwischen Verbindungselement und Abdeckung zur Illustration einer weiteren alternativen Ausführungsform

Figur 12:

eine Detailansicht eines Kontaktbereiches zwischen Verbindungselement und Abdeckung zur Illustration einer weiteren alternativen Ausführungsform.

Advantageous embodiments of the invention are explained below by way of example with reference to the accompanying drawings. Show it:

Figure 1:

a nozzle according to the invention in a side sectional view;

Figure 2:

a section of the figure 1 in enlarged view;

Figure 3:

that in the figure 2 shown safety shutdown module in an enlarged view;

Figure 4:

the safety shutdown module figure 3 in a different state;

Figure 5:

the safety shutdown module figure 4 in a cross-sectional view along another cutting plane;

Figure 5a:

a sectional view along the in figure 5 drawn line AA;

Figure 6:

a safety shutdown module of an alternative embodiment of a nozzle according to the invention;

Figure 7:

a detailed view of a contact area between the connecting element and cover to illustrate an alternative embodiment;

Figure 8:

a detailed view of a contact area between the connecting element and cover to illustrate a further alternative embodiment;

Figure 9:

a detailed view of a contact area between the connecting element and cover to illustrate a further alternative embodiment;

Figure 10:

a detailed view of a contact area between the connecting element and cover to illustrate a further alternative embodiment;

Figure 11:

a detailed view of a contact area between the connecting element and cover to illustrate a further alternative embodiment

Figure 12:

a detailed view of a contact area between the connecting element and cover to illustrate a further alternative embodiment.

figure 1 shows a dispensing valve according to the invention with an inlet 13 to which a dispensing hose for supplying a liquid fuel can be connected. The dispensing valve has a housing 12 into which an outlet pipe 11 is inserted. There is an outlet 14 at the end of the outlet pipe 11 . The inlet 13 is connected to the outlet 14 via a fluid channel 15 . In the fluid channel 15 there is a main valve 16, which is biased in a closing direction against a valve seat. The main valve 16 can be actuated by the hand lever 17.

For this purpose, the hand lever 17 is coupled in a manner known in principle to an inner valve stem 30 by means of an actuating pin 21, which in turn can be coupled to an outer valve stem by means of a coupling device. The coupling takes place by means of a safety shutdown module 23 which is inserted into the housing 12. The functioning of the safety shutdown module 23 is described below with reference to FIG Figures 2 to 5 explained in more detail.

figure 2 shows an enlarged section of the figure 1 . In figure 3 only the safety shutdown module 23 is shown in an enlarged view. It can be seen that the dispensing valve has a closing spring 34 which urges the outer shaft 31 in the closing direction (upstream). The upstream end of the outer shaft 31 lies in the in figure 2 shown state at the downstream end of the main valve 16, so that the main valve 16 is pressed against the valve seat 35 and thus held in the closed position.

In the state shown, the inner valve stem 30 is coupled to the outer valve stem 31 by means of a coupling device 22 . To this end, the coupling device 22 comprises a locking roller holder 33 in which the locking rollers 32 are mounted. There are locking openings 37 in both the outer valve stem 31 and the inner valve stem 30, which are in figure 2 state shown are aligned with each other, wherein the locking rollers 32 are inserted into the locking openings 37. An axial movement of the inner valve stem 30 is transmitted to the outer valve stem 31 by means of the locking rollers 32 . When the hand lever is actuated, the actuating pin 21 is moved downstream and the inner valve stem 30 is carried along by the actuating pin 21 . Due to the coupling mediated by the locking rollers 32 as described above, the outer valve stem 31 is carried along by the inner valve stem 30 and in this way is lifted off the main valve 16 counter to the closing force of the closing spring 34 . The main valve 16 can then be moved to the open position by an upstream fluid pressure.

The clutch device 22 is actuated with the aid of a membrane 26 which separates a first membrane space 27 from a second membrane space 28 . The coupling device 22 also includes a connecting element 36 that connects the membrane 26 to the locking roller holder 33 in which the locking rollers 32 are mounted. A movement of the membrane 26 can be transmitted to the locking rollers 32 in this way. In particular, the locking rollers 32 can be lifted out of the locking openings 37 by moving the membrane 26 upwards in order to decouple the inner valve stem 30 from the outer valve stem 31 .

The dispensing valve also has a vacuum line 38 which connects a venturi nozzle (not shown in the figures) positioned downstream of the main valve 16 to the diaphragm space 27 in order to apply a vacuum to the first diaphragm space. In addition, the sensor line 19 opens into the first diaphragm chamber 27 in the area 19'. During the dispensing of the fuel, air and/or fuel vapors are sucked in from the environment via the vacuum line 38, the first diaphragm chamber 27 and the sensor line 19 at the downstream end of the sensor line 19. If the end of the sensor line 19 is covered by the fuel level at the end of a refueling process, a negative pressure is created in the first diaphragm chamber 27 . This leads to a movement of the membrane 26 upwards in the direction of the first membrane space 27 (see figure 4 ), so that the locking rollers 32 are lifted out of the locking openings 37 in the manner explained above. The coupling between the inner valve stem 30 and the outer valve stem 31 is released accordingly, and the outer valve stem 31 is urged against the main valve 16 by the closing force of the closing spring 34, which is thereby moved to the closed position.

The second membrane chamber 28 is separated from the fluid channel 15 in a fluid-tight manner by a cover 40 . The fuel flowing through the fluid channel thus has no influence on the pressure inside the second membrane space 28. The second membrane space 28 is also connected via a ventilation channel 29 to the environment outside the dispensing valve. In the sectional view of figure 3 only the junction 42 of the ventilation channel 29 can be seen. The labyrinthine course of the ventilation channel 29 is in the figure 5 shown which the in the figure 3 represents elements shown along a different cutting plane. In particular, in figure 5 as well as in the Figure 5a , which is a sectional view along the in figure 5 drawn-in lines AA, it can be seen that a reversal of direction takes place several times along the ventilation duct 29, through which the ingress of dirt is prevented. The course of the ventilation channel 29 is in the Figures 5 and 5a partially illustrated by double arrows. In the figure 5 it can be seen in particular that the ventilation duct, starting from the membrane chamber 28, initially runs radially outwards (relative to the axis of the connecting element 36) and then branches off upwards, inwards, upwards, inwards and finally downwards. In Figure 5a it can be seen that the ventilation channel then (relative to the axis of the connecting element 36) in the circumferential direction (in the view of Figure 5a up and down) branches off and thus opens into a free space 43, which can in principle be open to the environment. However, he is Free space 43 in this case by an in figure 2 shown protective coating 44 covered in such a way that a pressure equalization between the free space 43 and the environment is possible. For this purpose, it can be provided that gaps or channels remain between the protective cover 44 and the outer wall of the housing 12 of the nozzle to ensure pressure equalization. At the same time, the protective cover 44 prevents dirt from entering the free space 43 (or the ventilation channel 29). Due to the connection of the second membrane space 28 with the environment, a pressure is always established in the second membrane space 28 which corresponds to the ambient pressure. The movement of the membrane 26 caused by the pressure difference prevailing between the membrane chambers 27, 28 and thus the actuation of the clutch device 22 can be realized in this way in a particularly safe and reliable manner.

The connecting element 36 has a cylindrical section which is passed through a corresponding through-opening in the cover 40 . In the area of the through-opening there is an inward-pointing groove into which a lip seal 41 is inserted. The lip seal 41 seals against the outer surface of the cylindrical section, so that the pressure within the membrane space 28 is not affected by the pressure conditions in the fluid channel. At the same time, the lip seal 41 allows a sliding movement of the connecting element 36 relative to the cover 40.

The area below the cover 40 is connected to the fluid channel 15 . The detent roller holder 33 and the detent rollers 32 are therefore washed around by the fuel while it is being dispensed. This results in continuous lubrication of the locking rollers 32 and the accumulation of dirt is avoided.

The embodiment of Figures 1 to 5 also includes a shutdown device integrated into the safety shutdown module 23, which is designed to move the main valve 16 into the closed position independently of a position of the hand lever 17 when a liquid pressure at the inlet 13 falls below a minimum value. The switch-off device is designed in a manner that is known in principle and should therefore not be described in detail here. In the in the Figures 2 to 4 In the states shown, there is sufficient pressure at the inlet 13 of the dispensing valve so that the shut-off device is activated and the main valve can be opened with the aid of the hand lever. in the in figure 5 The condition shown is that the pressure at the inlet is lower than the minimum pressure. Accordingly, the coupling device is in the uncoupled state and the main valve cannot be actuated.

the figure 6 12 shows the safety shutdown module 23 of an alternative embodiment of a nozzle according to the invention. This embodiment differs from the embodiment of FIG Figures 1-5 only due to the absence of the defeat device described above.

the Figures 7 to 12 14 each show partial views of alternative embodiments, each illustrating an enlarged cross-sectional view of the contact area between the connecting element 36 and the cover 40. FIG. In the embodiments of Figures 7-9 the cover 40 in the area of the through-opening has an inward-pointing groove into which different types of sealing elements 41 are inserted, namely an O-ring ( figure 9 ), an X ring ( figure 8 ) and a lip seal ( figure 7 ). The connecting element 36 is cylindrical in the area under consideration, the respective sealing element 41 being in annular contact with the cylindrical area.

In the embodiments of Figures 10 and 11 a groove open to the outside is let into the cylindrical area of the connecting element 36 . In this groove is in the embodiment of figure 10 an O-ring and in the embodiment of figure 11 fitted with a lip seal. In these embodiments, the through-opening of the cover 40 has a cylindrical inner surface which bears against the respective sealing element over its entire circumference. In the embodiment of figure 12 an outwardly open groove is embedded in the cylindrical area of the connecting element 36 and an inwardly open groove in the cylindrical area of the cover 40 . A membrane-like sealing element (membrane seal) 41 is inserted into these two grooves, which ensures sealing by means of a flexing membrane without surfaces rubbing against one another.

A good seal can be achieved by the types of seal mentioned, without the ability to slide between the cover 40 and the connecting element 36 being impaired too much.

Claims (10)

Nozzle valve, comprising an inlet (13) for connecting a fluid supply line, an outlet (14) for dispensing the fluid, a fluid channel (15) connecting the inlet to the outlet, a main valve (16) located in the fluid channel (15) and acting against a valve seat is biased into a closed position, a hand lever (17) for actuating the main valve (16), and a coupling device (22) which is operatively connected to the hand lever (17) and which, in the coupled state, is set up to prevent a movement of the hand lever (17 ) into an actuation of the main valve (16), the main valve (16) being urged into the closed position in the uncoupled state, regardless of the position of the hand lever (17), the dispensing valve also having a diaphragm (26) which has a first Membrane chamber (27) separates from a second membrane chamber (28) and through a between the first membrane chamber (27) and the second membrane chamber (28) existing pressure difference for actuating the Coupling device (22) is movable, wherein the first diaphragm space (27) can be acted upon by a vacuum and wherein a sensor line (19) opens into the first diaphragm space (27), characterized in that the second diaphragm space (28) opposite the fluid channel (15 ) and is fluidically connected via at least one ventilation channel (29) to an environment located outside the dispensing valve, with a part of the coupling device (22) located outside the second diaphragm space (28) being flushed with the fluid when the main valve (16) is open. Fuel nozzle according to Claim 1, in which the coupling device has a latching element (32) for latching the hand lever with a valve actuating element, the latching element can be moved into or out of a locking position by moving the membrane. 3. The dispensing valve according to claim 2, wherein the detent element is positioned such that the fluid washes around it when the main valve is open. A dispensing valve according to any one of claims 1 to 3, in which the second diaphragm space (28) is sealed off from the fluid passage (15) by a cover, the coupling means preferably having a connecting element connected to the diaphragm which slides through a through-opening in the cover is passed through. Fuel nozzle according to Claim 4, in which at least one sealing element (41), which is preferably designed as an O-ring, X-ring, lip seal or membrane seal, is arranged between the connecting element and the cover. A dispensing valve according to claim 5, wherein the connecting member has an outwardly facing circumferential groove into which the sealing member (41) is embedded. A dispensing valve according to claim 5 or 6, wherein the through opening of the cover has an inwardly directed circumferential groove into which the sealing member (41) is embedded. Nozzle according to one of Claims 1 to 7, in which the ventilation channel extends in the manner of a labyrinth up to an opening which faces the surroundings and which is preferably covered by a flexible protective covering (44) in such a way that pressure equalization is possible. A dispensing valve according to any one of claims 1 to 8, further comprising a shut-off device which controls the main valve moved to the closed position, regardless of the position of the hand lever, if the liquid pressure at the inlet falls below a minimum value. A petrol pump with a dispensing hose and a dispensing valve according to any one of claims 1 to 9, wherein the dispensing hose is connected to the inlet (13) of the dispensing valve.

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