DE102006009537B3 - Cylinder for compressed fuel-gas has pressure relief device with relief valve whereby relief valve has closing body which stops in closing position in crossover channel - Google Patents

Abstract

Cylinder (1) has a pressure relief device (2) with a relief valve (6). The relief valve has a closing body which stops in the closing position in a crossover channel over which the combustible gas can be lead from the inlet channel to the outlet channel of the relief valve by which the closing body reaches into a discharge chamber. A pressure signal line (3) is attached to the discharge chamber in the form of a high-pressure hose. A thermal release unit (4,5) is provided at a distance from the relief valve in the pressure signal line. Thermal release unit has bursting body with filling content. The closing body can be shifted freely, with the decrease of pressure, from the closing position to open position in the crossover channel.

Description

The The invention relates to a fuel pressurized gas container for a combustible gas a pressure relief device with a discharge valve.

Around the bursting of a pressure vessel due to increasing internal pressure, caused by external heat, To prevent, there are pressure relief devices directly at the usually cylindrical Compressed gas containers are arranged. These pressure relief devices will too referred to as a pressure relief device or as a thermofuse. The so-called thermofuse comprises a thermosensitive element, which responds when reaching a certain threshold temperature and usually destroyed irreversibly. About appropriate components the pressure relief device is then released a transfer channel, via which Gas can escape from the compressed gas container. This drops the pressure inside the gas cylinder, causing a burst is prevented.

A Pressure relief device of this type can increase the temperature naturally only locally detect. When the heat source now acts on the pressure vessel remote from the pressure relief device, does this in certain circumstances to a local exceedance the threshold temperature at which the pressure relief device trigger would, which is due to the spatial Removal did not happen. Only when the threshold temperature has been exceeded in the area of the pressure relief device speaks the pressure relief device on. Due to these technical reasons Tripping delay can the internal pressure in the meantime has risen sharply, so that the pressure vessel Danger runs, too burst.

The DE 199 11 530 C2 shows a safety device for a compressed gas container with a thermal trip unit, which has a movable in a housing from a standby position into a release cap having a guide shaft positioned in the standby position by a bursting body in a pressure gas container with an outlet channel connecting overflow channel and circumferentially with respect to the Overflow channel is sealed.

The DE 35 33 304 C2 shows a safety valve for connection between a source of pressurized fluid and a container to be pressurized. The housing has an inlet that connects to the source of pressurized fluid and an outlet that connects to the reservoir. The housing connects to the inlet and outlet via a pressure chamber. A frangible membrane is provided which separates the pressure chamber from the vented chamber and which breaks when a predetermined pressure is reached within the pressure chamber. Furthermore, valve formations are provided in the housing which cooperate with the frangible membrane and block the inlet and outlet as the membrane breaks.

From the DE 28 13 219 A1 is a release valve for carbonated containers known. In a housing, a standing under spring tension opening bolt is provided, which opens a pressurized gas container when it is triggered. In the opening bolt engages under spring tension transverse transverse locking pin, which is part of a Berstkörperauslösevorrichtung.

By the DE 838 531 C a safety device for pressure vessels is known in the art. This has a Abblaseorgan, for example, a pressure plate which is dimensioned so that it would respond to an overpressure, wherein an auxiliary force is provided which triggers a pressure applied by the pressure vessel and the diaphragm, the response is forced automatically at the desired Abblasedruck.

A temperature controlled safety device for high pressure gas containers shows the DE 298 09 230 U1 on. The safety device has a pressure bore which can be closed by a rupture disk, which is held by a thermal release element. The thermal release element is a glass ampoule, which is destroyed when a certain internal pressure, exerted by the thermal expansion of the liquid contained, is exceeded.

From the DE 602 08 563 T2 goes out a monitoring system for a pressure vessel. The monitoring system has a sensor and a control unit. The sensor is used to monitor the pressure vessel.

The DE 695 12 285 T2 shows an impact-proof solenoid valve for a natural gas-powered vehicle. The valve has a housing in which a valve body is disposed between an inlet and an outlet. The valve body is electromagnetically actuated and blocks the passage in the bidirectional direction.

Another temperature and overpressure protection device is further by CH 671 278 A5 demonstrated. The temperature and overpressure protection device is responsive to self-destruct on reaching a certain response temperature or by remote triggering provided by a detonator destructible burst body. The bursting body is provided in the form of a bursting vessel filled with an expansion fluid and supported by a support.

Of these, Based on the invention, the object is to show a fuel gas tank, which is better protected against bursting in case of fire.

These Task is with a fuel gas container with the features of Patent claim 1 solved. Advantageous developments are the subject of the dependent claims.

Of the Fuel gas container according to the invention comprises a pressure relief device with a relief valve. The Relief valve has a closure body in the closed position a transfer channel locks, over which the combustible gas from the interior of the gas cylinder of the at the compressed gas tank connected inlet channel in an outlet channel of the relief valve can be transferred is. The closure body is guided in a discharge chamber, which has a Equalizing channel with the combustible gas and the internal pressure of the compressed gas tank acted upon is. To the discharge chamber is a pressure signal line in the form a high-pressure hose connected to at least one arranged by the high-pressure hose at a distance from the relief valve, when triggered causing a pressure drop in the pressure signal line, thermal trip unit is provided, which a burst body with a filling content contains. The closure body is due to the pressure drop from the closure position in a the bypass channel releasing Open position relocatable.

Of the essential advantage of the fuel-gas container according to the invention, that the pressure relief device regardless of their spatial Location and independent be triggered by the positioning of the gas cylinder can. This can reduce the trip delay become. With the appropriate distance of the thermal trip unit from the compressed gas tank is it even possible imminent temperature effects on the compressed gas tank too so that the temperature increase can not be dangerous.

The Pressure signal line can be connected to any number of thermal trip units be provided. The arrangement of the thermal trip units is from the local Conditions dependent. For example, could the pressure signal line run parallel to the longitudinal axis of the fuel-compressed gas container, so that with a corresponding number of thermal trip units a much better detection of local temperature conditions on the compressed gas tank is possible as in a single pressure relief device. The relief valve is basically directly on the fuel gas cylinder, this means to be protected Object attached. To allow rapid pressure relief, the relief valve has a transfer channel with a relatively large nominal size from e.g. 10 mm to 14 mm. By contrast, the pressure signal line has a comparatively small cross-section of e.g. 2 mm to 3 mm. This small cross section is perfect for inducing a pressure drop sufficient. Important in this context is that the gas off the compressed gas tank no over the pressure signal line, but via the transfer channel flow out should.

The Pressure signal line with the small cross-section also has a only slightly larger outer diameter and is therefore particularly light and preferably flexible. It only wears depending on the length Insignificant to the total weight of the pressure relief device at.

In the closure position, the closure body is held by a spring. The spring force is chosen smaller as the force emanating from the inlet channel at a pressure drop of the overflowing gas. The closure body is designed as a so-called pressure differential piston, wherein the smaller Cross sectional area facing the inlet channel and its larger cross-sectional area to the discharge chamber shows. At pressure equilibrium of the closure body is exclusively by the spring held in the closed position. At a pressure drop leads the Difference in cross-sectional areas to the desired Displacement of the closure body against the spring force.

Of the Compensation channel for the induction the pressure equilibrium on both sides of the closure body preferably designed as a bore in the closure body itself. These so-called pilot hole can have a very small cross-section and serves only for the production of pressure equalization. under no circumstances should over the pilot hole a larger volume of gas flow out. This pilot bore is in particular centric and longitudinal of the closure body progressively placed.

The closure body itself is preferably sealed circumferentially with respect to the transfer channel. In addition, a further circumferential seal against the discharge chamber is provided so that even in the closed position no fuel from the discharge chamber or the pressure signal line connected thereto can escape. In the closed position, the closure body is in both the transfer channel and guided circumferentially within the discharge chamber, so that the closure body is properly position-oriented, even if the transfer channel is released.

The connected to the discharge chamber pressure signal line is preferably a flexible high-pressure hose. Due to its small cross-section let yourself easy to lay the pressure signal line and claimed in particular in the automotive sector little space. Basically it is conceivable that the Pressure signal line is not only single-stranded, but multi-stranded, this means, that branch the printing signal line, for example, on T-pieces or Y-pieces can. In this way, the pressure signal line can be called as Network configured.

The Thermal trip units connected to the pressure signal line preferably have a bursting body when exceeded a threshold temperature bursts. The bursting body stops you when you burst outflow channel releasing blocking body. This locking body becomes out of its rest position by the internal pressure of the pressure signal line hurled and allows that gas escapes from the pressure signal line with the result that at the discharge chamber the pressure drops.

Of the outflow channel the thermal trip units can be either longitudinally the pressure signal line point. This is especially the case when the thermal trip unit end the pressure signal line is attached. The thermal trip unit but can also have a transversely extending to the outflow passage, at which both ends the pressure signal line can be connected. In this configuration, the discharge channel forms with the passage so to speak a T-shaped Branch, wherein the branch is closed by the blocking body.

In Regarding the relief valve, it is considered advantageous when the spring within the pressure relief device at a in the closure body recorded spring inner guide supported is. This spring inside guide forms with the closure body an annular space in which the spring is guided. This will be the Improved functional reliability of the pressure relief device. To equalize the pressure between the discharge chamber and the interior of the compressed gas tank to enable the compensation channel is preferably also guided by the spring inner guide.

All in all it is considered appropriate if the discharge chamber in a connecting piece for the pressure signal line is formed, wherein the connecting piece transversely to the inlet channel is screwed to the relief valve. This allows a very compact design at low height, as it is aimed in particular in the motor vehicle sector. As the pressure relief device according to the invention no bursting body or a thermal trip unit has at least one thermal trip unit via the pressure signal line near be arranged the pressure relief device.

The Invention is particularly suitable for compressed gas containers, the used in the automotive sector. In the recorded in the fuel pressure gas container Gas can be both gaseous and liquid gas act. In particular, it is natural gas (CNG), that is methane or LPG, this means a mixture of propane and butane.

Just In the context of motor vehicles, fuel pressurized gas cylinders are particularly dangerous exposed. For example, a cylindrical fuel pressurized gas container in Composite construction local thermal stresses in its middle Area materially very poor at its ends, where pressure relief devices are arranged. On the other hand it uneconomical, thermal trip units in very low intervals to arrange along a pressure signal line, so a gapless Temperature detection also in the range of a fuel gas cylinder enable. It is therefore considered appropriate if the pressure signal line itself is formed meltable. This allows impermissible temperature increases over the entire course of the signal line can be detected and not only in the field of thermal tripping units. additionally should at defined, especially fire risk points thermal trip units be arranged over there the thermal trip units realized a more accurate triggering can be considered over meltable pressure signal lines. For example, it is also conceivable that in the engine compartment of a motor vehicle only at a temperature above of 150 ° C a trip takes place should, while in other areas of the vehicle, where usually no heat is expected to be triggered already at a temperature of 110 ° C should. These different requirements can be a uniform signal line do not do it justice. It is therefore in addition to the meltable executed pressure signal line trip units required.

A particular advantage of fusible signal lines is that they can be wrapped around them in the area of the fuel pressurized gas containers. Looping in this context is not necessarily a wrapping of the force Instead, it means that a fuel-compressed gas container is protected by an additional, arranged in its immediate vicinity signal line, which is arranged, for example, meandering or serpentine in the region of the fuel-compressed gas container. The safety advantages are particularly serious in composite gas pressure containers, since such containers can be spanned in a manner of net like pressure lines in particular in cylindrical form, so that local temperature increases detected and can reliably lead to a pressure relief by triggering.

The invention will be described below with reference to the 1 to 4 illustrated embodiments explained in more detail. It shows:

1 a perspective view of a fuel pressure gas container with a pressure relief device;

2 the pressure relief device of 1 in longitudinal section;

3 a first embodiment of the thermal trip unit in longitudinal section and

4 a second embodiment of a thermal trip unit in longitudinal section.

1 a fuel gas container 1 in the form of a cylinder. This fuel gas cylinder 1 is at one end with a pressure relief device 2 Mistake. The pressure relief device 2 includes a relief valve 6 and a pressure signal line 3 in the form of a flexible high-pressure hose, which in the illustrated variant approximately the length of the fuel-compressed gas container 1 has. The pressure signal line 3 is with two thermal trip units 4 . 5 Mistake. A first thermal trip unit 4 is configured as a T-piece, with the pressure signal line 3 on both sides of the thermal trip unit 4 continues. The second thermal trip unit 5 is at the far end of the pressure signal line 3 attached. The closer construction of the fuel gas tank 1 screwed relief valve 6 or the thermal trip units 4 and 5 is described below on the basis of 2 to 4 explained.

2 shows the relief valve 6 of the 1 in longitudinal section. It is a valve housing 7 to recognize that over a threaded connector 8th into the fuel gas cylinder 1 is screwed in. Essential part of the relief valve 6 is a transverse to the orientation of the threaded neck 8th movable closure body 9 , The closure body 9 is in the illustrated position in the closed position. This prevents the closure body 9 in that combustible gas from the interior of the pressure vessel via an inlet channel 10 that goes through the threaded connector 8th extends into an exhaust duct 11 flows. The outlet channel 11 is in this embodiment in the image plane above the entrance channel 10 , The outlet channel 11 and the central longitudinal axis MLA of the relief valve 6 have the same orientation.

In the area of the outlet channel 11 is a discharge hood 12 in the valve body 7 screwed. The exhaust hood 12 has several holes on its outer circumference 13 on, over which the outflowing gas laterally, that is transverse to the central longitudinal axis MLA of the valve housing 7 flows.

The entrance channel 10 and the outlet channel 11 are via a transfer channel 14 connected in the representation of 2 from the front portion of the closure body 9 Is blocked. The closure body 9 is therefore in the above-mentioned closure position. He is in this closing position of a spring 15 held, which the closure body 9 in the picture plane from left to right against a covenant 16 urges. The feather 15 is located in a discharge chamber 17 , in turn, in a longitudinally channeled connection piece 18 is trained. This connection piece 18 is transverse to the central longitudinal axis MLA in the valve housing 7 screwed in and stands with the inlet channel 10 via a compensation channel 19 in connection. The equalization channel 19 is initially as a small diameter bore in the inlet channel 10 facing the end of the closure body 9 educated. In its further course towards the discharge chamber 17 is another hole 19a in a spring interior guide 20 to recognize which in the closure body 9 is included. The spring inner guide 20 is pin-shaped and is a separate component of the spring 15 in the image plane to the right, that is in the interior of the multi-stage sleeve-like closure body 9 pressed into it. The spring inner guide 20 forms together with the closure body 9 an annulus in which the spring 15 is conducted on both sides. The summit 21 the spring inner guide 20 is rounded and enters the open position of the closure body 9 that is, when the closure body 9 with the spring inside guide 20 is displaced to the left, at an outflow channel 22 to the plant, the funnel-shaped mouth area 23 has, in which the tip 21 the spring inner guide 20 sets. This prevents gas in the open position from the fuel pressure gas container into the connection piece 18 connected pressure signal line 3 flows in or flows over this. The summit 21 the spring inner guide 20 serves for this purpose, so to speak, as a valve body, whereas the mouth 23 the outflow channel 22 acts as a valve seat.

The closure body 9 is in the transfer channel 14 guided circumferentially and a sealing ring 24 sealed on the circumference. Another sealing ring 25 is at the other end of the closure body 9 provided and seals this circumferentially opposite the discharge chamber 17 from. Between these two sealed areas is an annulus 26 as part of the transfer channel 15 , The annulus 26 has a much larger diameter than the transfer channel 15 and thus a larger diameter than the closure body 9 , The annulus 26 therefore surrounds the entire closure body 9 and has a sufficient cross-sectional area to allow substantially unimpeded outflow of the gas. The annulus 26 is fluid-conducting with another annulus 27 the outlet channel 11 in connection. The two annular spaces 26 . 27 are arranged substantially perpendicular to each other.

3 shows a possible embodiment of a thermal trip unit 5 as they are in 1 is shown. The thermal trip unit 5 has a cylindrical housing with a longitudinally extending outflow channel 29 that of a locking body 30 is blocked. The locking body 30 is in the illustrated ready position of a burst body 31 held. In the burst body 31 it is preferably a glass body with a filling with a high coefficient of thermal expansion. The bursting body 31 bursts when a threshold temperature is exceeded, so that the blocking body 30 by the pressure applied in the image plane from below from the outflow channel 29 is thrown. The not shown in detail from below connected pressure signal line 3 applied pressure can be bored through peripheral holes 32 in the housing of the trip unit 5 escape laterally. The resulting pressure drop in the connected pressure signal line 3 leads to a pressure drop in the discharge chamber 17 and thus to a displacement of the closure body 9 in an open position. As a result, gas from the fuel gas cylinder 1 over the outlet channel of the valve body 7 flows.

The embodiment of the thermal trip unit according to 4 is different from the one of 3 by the orientation of the outflow channel 29 , Regarding the bursting body 31 or the blocking body 30 Turns to the above explanation 3 and the reference numbers introduced there referenced. at 4 is only a passage 33 to recognize, at right angles to the discharge channel 29 runs. As a result, the passageway forms 33 together with the discharge channel 29 sort of a tee. The passage 33 allows it on both sides of the case 34 this thermal trip unit 4 Pressure signal lines 3 can be connected. In this way, a variety of thermal trip units 4 be connected in series.

1

Fuel pressure gas container

2

Pressure relief device

3

Pressure signal line

4

thermal trip unit

5

thermal trip unit

6

relief valve

7

Valve housing v. 6

8th

threaded connector

9

closure body

10

inlet channel

11

exhaust port

12

Abströmhaube

13

drilling

14

transfer channel

15

feather

16

Federation

17

relief chamber

18

spigot

19

compensation channel

19a

drilling

20

Spring inside guide

21

Top v. 20

22

outflow

23

Estuary v. 22

24

seal

25

seal

26

annulus

27

annulus

28

Housing v. 5

29

outflow channel

30

blocking body

31

bursting body

32

Bore in 28

33

Durchleitkanal

34

casing

MLA

central longitudinal axis

Claims (16)

Fuel gas cylinder for a combustible gas comprising a pressure relief device ( 2 ) with a relief valve ( 6 ), the relief valve ( 6 ) a closure body ( 9 ), which in the closed position has a transfer channel ( 14 ) locks, via which the combustible gas from the to the compressed gas container ( 1 ) connected inlet channel ( 10 ) in an outlet channel ( 11 ) of the relief valve ( 6 ) is transferable, wherein the closure body ( 9 ) into a discharge chamber ( 17 ), which have a compensation channel ( 19 ) with the combustible gas and the internal pressure of the compressed gas container ( 1 ) is applied to the discharge chamber ( 17 ) a pressure signal line ( 3 ) in the Form a high-pressure hose connected to at least one through the high-pressure hose at a distance from the relief valve ( 6 ), when triggered a pressure drop in the pressure signal line ( 3 ) inducing thermal tripping unit ( 4 . 5 ), wherein the at least one thermal trip unit ( 4 . 5 ) a bursting body ( 31 ) with a filling content, and wherein the closure body ( 9 ) by the pressure drop from the closure position into a the Überleitkanal ( 14 ) releasing open position is relocatable. Fuel-compressed gas container according to claim 1, characterized in that the closure body ( 9 ) of a spring ( 15 ) is held in the closed position, wherein the spring force is smaller than that at a pressure drop from the inlet channel ( 10 ) outgoing force of the overflowing gas. Fuel-compressed gas container according to claim 1 or 2, characterized in that the compensation channel ( 19 ) as a bore in the closure body ( 9 ) is executed. Fuel-compressed gas container according to one of claims 1 to 3, characterized in that the closure body ( 9 ) opposite the transfer channel ( 14 ) is circumferentially sealed. Fuel-compressed gas container according to one of claims 1 to 4, characterized in that bursting body ( 31 ) one when bursting an outflow channel ( 29 ) releasing blocking body ( 30 ) holds. Fuel-compressed gas container according to claim 5, characterized in that the thermal trip unit ( 5 ) end of the pressure signal line ( 3 ) is attached, so that the outflow channel in the longitudinal direction of the pressure signal line ( 3 ). Fuel-compressed gas container according to claim 5, characterized in that the thermal tripping unit ( 4 ) a transversely to the discharge channel ( 29 ) passing passage ( 33 ), at which both ends the pressure signal line ( 3 ) is connectable. Fuel-compressed gas container according to one of claims 1 to 7, characterized in that the pressure signal line ( 3 ) is a flexible high-pressure hose. Fuel-compressed gas container according to one of claims 1 to 8, characterized in that the spring ( 15 ) at one in the closure body ( 9 ) spring internal guide ( 20 ) is supported. Fuel-compressed gas container according to one of claims 1 to 8, characterized in that the compensation channel by the spring inner guide ( 20 ) is guided. Fuel-compressed gas container according to one of claims 1 to 10, characterized in that the discharge chamber ( 17 ) in a connecting piece ( 18 ) for the pressure signal line ( 3 ) is formed, which transverse to the inlet channel ( 10 ) to the relief valve ( 6 ) is screwed. Fuel-compressed gas container according to one of claims 1 to 11, characterized in that a discharge chamber ( 17 ) with the pressure signal line ( 3 ) connecting outflow channel ( 22 ) in the open position of the closure body ( 9 ) is closed. Fuel-compressed gas container according to claim 9, characterized in that the spring inside leadership ( 20 ) a peak ( 21 ), wherein the tip ( 21 ) of the spring inner guide ( 20 ) in the open position of the closure body ( 9 ) one the discharge chamber ( 17 ) with the pressure signal line ( 3 ) connecting outflow channel ( 22 ) locks. Fuel-compressed gas container according to one of claims 1 to 13, characterized in that the pressure signal line ( 3 ) is meltable. Fuel-compressed gas container according to claim 14, characterized in that the pressure signal line ( 3 ) melts in a temperature range above 110 ° C. Fuel-compressed gas container according to one of claims 1 to 15, characterized in that it from the pressure signal line ( 3 ) is entwined.