GB1591604A - Device for filling a tank of a vehicle - Google Patents

Description

(54) A DEVICE FOR FILLING A TANK OF A VEHICLE (71) We, SOCIETE NATIONALE INDUS TRIELLE AEROSPATIALE, a French Body Corporate of 37 Boulevard de Montmorency, Paris, France, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:- The invention relates to a device for filling a tank of a vehicle, and may find particular application as a filling device for a fuel tank on an aircraft.

Devices for filling fuel tanks on aircraft, e.g. helicopters, are exposed to serious risks of damage, inter alia when the aircraft falls to the ground and overturns so that the filling device is deformed or broken, in which case the spilt fuel may of course catch fire and burn the helicopter.

A known device for filling a fuel tank on an aircraft is constructed so as substantially to prevent any fuel being ejected from the tank if the filling device is seriously damaged. The known filling device comprises a first flange, collar or the like for a plug, the collar being rigidly secured to the aircraft structure and a second collar bearing a filling tube and provided with a valve which is subjected by a resilient means to a closing pressure towards the plug. In the known device the first and the second flange are relatively thick (of the order of 12 mm) and are directly connected by a thinner, breaking portion, the second flange being rigidly secured to the edge of the filling hole in the tank wall.When the filling device is subjected to considerable external forces transmitted via the aircraft structure and the first flange, the first flange becomes separated from the second flange at the breaking portion, provided the second flange and the tank wall to which it is secured are sufficiently rigid to withstand the reactive forces resulting from the aforementioned external forces. To meet the iast-mentioned condition, the tank wall must itself be sufficiently rigid and thick-i.e. the known filling device is not adaptable to tanks having flexible walls.

Furthermore, since the two flanges of the known device must be thick, the device must be relatively heavy, which is undesirable for applications to light helicopters. In addition, the valve associated with the filling tube of the known device is disposed at the bottom end of the tube and can be opened only by the pressure of the stream of fuel coming out of the supply rod introduced into the filling tube. At the end of the filling operation, when the flow rate of fuel decreases, the valve may be prematurely closed by the corresponding resilient means.

The invention relates to a device for filling a tank of a vehicle which likewise comprises a first flange, collar or the like for a plug, the first flange being rigidly secured to the vehicle structure, and a second flange bearing a filling tube provided with a valve which is subjected by a resilient means to a closing pressure in the direction of the plug. The filling device according to the invention however, does not have any of the aforementioned disadvantages of the known device; it is characterised in that one end of the filling tube is slideably mounted, with interposition of an annular gasket, in the second flange which in turn is rigidly secured to the vehicle structure, and a sealing-tight bellows is disposed between the outer wall of the filling tube and the edge of the filling hole in the tank wall.When the outer part of the filling device according to the invention is subjected to sufficient force to tear off the plug, e.g. if the aircraft falls to the ground, the valve, which is kept in the closed position by the corresponding resilient means, prevents the fuel coming out of the tank. If however, the filling device is subjected to even stronger forces which smash in the aircraft structure around the flanges of the filling device, both of which are rigidly secured to the aircraft structure, the filling tube can slide in the second flange and, if required move with respect to the tank walls, owing to the deformability of the bellows, without any fuel escaping from the tank. This results from the sealing-tightness of the valve and from the fact that the valve is held in the closed position.The latter advantageous result is obtained even if the first flange of the filling device, the associated plug and the adjacent parts of the aircraft structure are substantially destroyed. In that case, more particularly, a relatively considerable length of the filling tube may be driven into the tank by the external forces without fuel leaking.

Since the two flanges of the filling device according to the invention are independent of one another and do not have to withstand considerable forces, they and the filling tube can have relatively thin walls, so that the entire device according to the invention is much lighter than the aforementioned prior art device, which is particularly advantageous for application to light helicopters. On the other hand, since the second flange of the filling device according to the invention is independent of the tank walls. it does not directly transmit to them any considerable external forces applied to it. Since the tank walls do not have to contribute to the resistance of the second flange to external forces, they do not need high rigidity or strength.Consequently, the filling device according to the invention can be applied to a tank having either flexible or rigid walls. It can even be applied to special kinds of aircraft fuel tanks comprising means giving protection against perforation by bullets.

Another known aircraft tank filling device likewise comprises a flange, collar or the like for a plug and secured to the aircraft structure by a breakable element. The flange is rigidly secured to a first end of a filling tube, which rigidly fits in a filling hole formed in the tank wall. Even if considerable external forces break the breakable elements and detach the flange from the aircraft structure, the forces are still transmitted to the tank wall via the filling tube, which is rigidly secured thereto. There is consequently a serious risk of fuel leaking from the portion of the filling tube outside the tank.

To obviate this disadvantage, the known filling device also comprises a sealing-tight bellows surrounding the external portion of the filling tube. Of course, this sealing-tight bellows does not serve the same purpose as in the filling device according to the invention since, in the prior-art device, the filling tube is rigidly secured to the tank wall. Finally, the known device does not comprise a valve which prevents any leak of fuel even after the plug has been torn off.

In a preferred embodiment of the filling device according to the invention the valve is disposed in the filling tube so as to be pushed into the open position by a supply pipe when introduced into the filling tube. This prevents the risk of prematurely closing the valve as mentioned in the case of the prior-art filling device, in which the valve is opened by the stream of fuel coming out of the supply pipe.

By way of example, an embodiment of the filling device according to the invention mounted on a helicopter fuel tank, is described hereinafter and diagrammatically illustrated in the accompanying drawings, in which: Figure 1 shows the embodiment in section through a plane through the filling tube axis, and Figure 2 shows a detail A on a larger scale.

The drawings show a helicopter structure wall 1 formed with a recess la. Recess la is bounded at the bottom by a wall element lb which is preferably disposed so that it is slightly inclined to the horizontal when the helicopter is on the ground in its normal position. A first flange 3, e.g. metal, is secured by bolts 2 above a circular hole in wall element lb. Flange 3 can have relatively thin walls, and it is adapted to receive a conventional removable plug 4. A second flange 5 is secured, if required by the same bolts 2, to the inner surface of wall element lb. In the embodiment under consideration, flange 5 is a substantially cylindrical collar made of thin sheet metal and having an internal annular groove 5a in its central part, groove 5a having a substantially semicircular crosssection.An e.g. metal filling tube 6 having thin walls has a top end which slides in flange 5. A conventional annular gasket 7 is secured in a circular groove 6a formed externally in a thick portion of the top end of tube 6. In the normal operating position, gasket 7 engages in both grooves 5a and 6a so as to secure tube 6 in flange 5 as illustrated in the drawing.

However, the system is such that if a given force is applied to the top end of tube 6 gasket 7 comes out of the inner groove 5a of flange 5 so that tube 6 can slide downwards inside flange 5.

A pivoting valve 8 is mounted in the central part of the filling tube 6 and a resilient means, inter alia a metal wire spring 8a, permanently holds valve 8 in the closed position by thrusting it in the direction towards plug 4. A conventional strainer is mounted in the bottom end of tube 6.

Reference 10 denotes the tank wall, which can be either flexible or rigid and can have any required thickness. Wall 10 has a filling hole through which the filling tube 6 extends into the tank. A sealing-tight bellows 11, e.g.

made of reinforced elastomer, is placed between (a) the edge of the filling hole in the tank wall, to which the top end of bellows 11 is vulcanized and (b) the outer wall of the bottom end of tube 6. The bottom end of bellows 11 has a collar 11 a which is used for connecting it to the end of the filling tube 6 via a clamping collar or flange 12.

In order to fill the tank by means of the aforementioned filling device, it is sufficient to withdraw plug 4 and then insert a fuel supply pipe inside the filling tube 6 until the downward opening thrust exerted by the supply pipe on valve 8 is sufficient to overcome the force of spring 8a. The fuel conveyed by the supply pipe can then flow freely inside the tank through the filter or strainer 9 without any risk of valve 8 prematurely closing when the fuel flow rate decreases at the end of the filling operation.

In the operating position the filling device according to the invention is kept sealingtight by two distinct means i.e. valve 8 and plug 4.

If a helicopter equipped with the aforementioned filling device falls to the ground and overturns so that the filling device and, possibly, the corresponding part of the helicopter structure 1 come into violent contact with the ground or various structures, the least that can occur is for plug 4 to be torn out. In that case, any leakage of fuel from the tank is prevented by valve 8 which spring 8a holds in the closed position.

In the worst eventuality, i.e. destruction of all that part of structure 1 near plug 4, inter alia the various components of the recess la together with flange 3, tube 6 may be subjected to strong thrust towards the interior of tank 10.

As a result of this thrust, bellows 11 is extended but still keeps tank 10 sealing-tight, both at the filling hole, to which the bellows is vulcanized, and at the other end of the bellows, which is firmly secured to the bottom end of the filling tube. If the second flange 5 has not been damaged, the aforementioned thrust pushes gasket 7 out of groove 5a, so that the corresponding end of tube 6 can slide freely in flange 5. If, however, the flange has been damaged or destroyed, it of course does not resist the motion of tube 6. In both cases, the filling device is still sealed by valve 8, which is held closed by spring 8a.

The invention is not restricted to the aforementioned embodiment, but includes modified embodiments within its scope. The construction of the bellows, inter alia the material of which it is made and the methods of securing one end of the valve to the tank walls and the other end to the filling tube may be modified. As stated, valve 8 is preferably disposed inside tube 6, but this is an optional feature. Gasket 7, instead of being secured in the circular groove 6a of the filling tube 6 may be secured in circular groove 5a in flange 5 if the cross-sections of the said grooves are reversed compared with those shown in the drawings. In that case, gasket 7 will remain secured to flange 5 when the filling tube 6 moves.

Of course, the filling device according to the invention can be mounted on any kind of tank of any vehicle which may be overturned, e.g. an armoured vehicle.

WHAT WE CLAIM IS: 1. A device for filling a tank of a vehicle, the device comprising a first flange, collar or the like for a sealing plug, the said first flange being rigidly secured to the vehicle structure, and a second flange bearing a filling tube provided with a valve, on which resilient means applies a closing thrust in the direction of the said plug, and being characterised in that one end of the filling tube is slidably mounted, with interposition of an annular gasket, in the second flange which is also rigidly secured to the vehicle structure, and a sealing-tight bellows is disposed between the outer wall of the filling tube and the edge of the filling hole in the tank wall.

2. A device according to Claim 1, characterised in that the annular gasket is secured in an annular groove in the wall of the second flange or in the wall of the filling tube.

3. A device according to Claim 1 or Claim 2, characterised in that the valve is disposed in the filling tube so that it is pushed into the open position by a supply pipe when the latter is introduced into the filling tube.

4. A device according to any of Claims 1 to 3, characterised in that the bellows is made of a reinforced elastomer and one of its ends is vulcanised to the tank wall whereas its other end is secured to the filling tube by a collar or flange.

5. A device for filling a vehicle as claimed in any one of the preceding claims wherein the vehicle is an aircraft and the tank is a fuel tank of the aircraft.

6. A device for filling a tank of a vehicle substantially as hereinbefore described with reference to, and as shown in, the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (6)

**WARNING** start of CLMS field may overlap end of DESC **. bellows 11 has a collar 11 a which is used for connecting it to the end of the filling tube 6 via a clamping collar or flange 12. In order to fill the tank by means of the aforementioned filling device, it is sufficient to withdraw plug 4 and then insert a fuel supply pipe inside the filling tube 6 until the downward opening thrust exerted by the supply pipe on valve 8 is sufficient to overcome the force of spring 8a. The fuel conveyed by the supply pipe can then flow freely inside the tank through the filter or strainer 9 without any risk of valve 8 prematurely closing when the fuel flow rate decreases at the end of the filling operation. In the operating position the filling device according to the invention is kept sealingtight by two distinct means i.e. valve 8 and plug 4. If a helicopter equipped with the aforementioned filling device falls to the ground and overturns so that the filling device and, possibly, the corresponding part of the helicopter structure 1 come into violent contact with the ground or various structures, the least that can occur is for plug 4 to be torn out. In that case, any leakage of fuel from the tank is prevented by valve 8 which spring 8a holds in the closed position. In the worst eventuality, i.e. destruction of all that part of structure 1 near plug 4, inter alia the various components of the recess la together with flange 3, tube 6 may be subjected to strong thrust towards the interior of tank 10. As a result of this thrust, bellows 11 is extended but still keeps tank 10 sealing-tight, both at the filling hole, to which the bellows is vulcanized, and at the other end of the bellows, which is firmly secured to the bottom end of the filling tube. If the second flange 5 has not been damaged, the aforementioned thrust pushes gasket 7 out of groove 5a, so that the corresponding end of tube 6 can slide freely in flange 5. If, however, the flange has been damaged or destroyed, it of course does not resist the motion of tube 6. In both cases, the filling device is still sealed by valve 8, which is held closed by spring 8a. The invention is not restricted to the aforementioned embodiment, but includes modified embodiments within its scope. The construction of the bellows, inter alia the material of which it is made and the methods of securing one end of the valve to the tank walls and the other end to the filling tube may be modified. As stated, valve 8 is preferably disposed inside tube 6, but this is an optional feature. Gasket 7, instead of being secured in the circular groove 6a of the filling tube 6 may be secured in circular groove 5a in flange 5 if the cross-sections of the said grooves are reversed compared with those shown in the drawings. In that case, gasket 7 will remain secured to flange 5 when the filling tube 6 moves. Of course, the filling device according to the invention can be mounted on any kind of tank of any vehicle which may be overturned, e.g. an armoured vehicle. WHAT WE CLAIM IS:

1. A device for filling a tank of a vehicle, the device comprising a first flange, collar or the like for a sealing plug, the said first flange being rigidly secured to the vehicle structure, and a second flange bearing a filling tube provided with a valve, on which resilient means applies a closing thrust in the direction of the said plug, and being characterised in that one end of the filling tube is slidably mounted, with interposition of an annular gasket, in the second flange which is also rigidly secured to the vehicle structure, and a sealing-tight bellows is disposed between the outer wall of the filling tube and the edge of the filling hole in the tank wall.

2. A device according to Claim 1, characterised in that the annular gasket is secured in an annular groove in the wall of the second flange or in the wall of the filling tube.

3. A device according to Claim 1 or Claim 2, characterised in that the valve is disposed in the filling tube so that it is pushed into the open position by a supply pipe when the latter is introduced into the filling tube.

4. A device according to any of Claims 1 to 3, characterised in that the bellows is made of a reinforced elastomer and one of its ends is vulcanised to the tank wall whereas its other end is secured to the filling tube by a collar or flange.

5. A device for filling a vehicle as claimed in any one of the preceding claims wherein the vehicle is an aircraft and the tank is a fuel tank of the aircraft.

6. A device for filling a tank of a vehicle substantially as hereinbefore described with reference to, and as shown in, the accompanying drawings.