GB2304821A

GB2304821A - Fuel supply equipment for a vehicle fuel supply system

Info

Publication number: GB2304821A
Application number: GB9621413A
Authority: GB
Inventors: Klaus-Bernhard Laue; Karl Mielich; Kurt Frank; Werner Schmid; Wolfgang Soyer; Hans-Joachim Kuppel; Hellmut Kegel; Bernhard Lucas; Ulrich Projahn
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 1992-12-15
Filing date: 1993-12-14
Publication date: 1997-03-26
Anticipated expiration: 2013-12-14
Also published as: GB2304821B; GB9621413D0

Abstract

Fuel supply equipment for the supply of an internal combustion engine of a motor vehicle with fuel comprises a fuel storage tank, in which is arranged unit 414 having a fuel conveying device 417 is disposed for supplying fuel to the engine. At least one device ie filter 454 or the influencing of the fuel is arranged in the fuel-conveying path. The filling of the unit's casing 420 is ensured by a filling valve (non-return valve) 466 and a jet pump 460, 462 and 464. The jet pump is operated by excess fuel 472 flowing back in duct 473 from the engine or by a branch flow 474 from the pressure side of the device 417.

Description

FUEL SUPPLY EQUIPMENT FOR A VEHICLE FUEL SUPPLY SYSTEM The present invention relates to fuel supply equipment for a vehicle fuel supply system.

In conventional supply systems, components, such as a conveying pressure regulator, pressure wave damper, fuel filter, fuel conveying unit and so forth, influencing the fuel or fuel flow are arranged along the conveying path. Each of these components is mounted individually, which is expensive in the limited installation space available in motor vehicles. If a defect becomes evident after the final testing of the system, its elimination may be relatively difficult.

According to the present invention there is provided fuel supply equipment for a vehicle fuel supply system, comprising a fuel tank and a unit which is arranged in the tank and comprises a carrier element, a fuel conveying device for conveying fuel out of the tank and at least one device for influencing such fuel or a flow, thereof before or after conveying by the conveying device, the carrier element being provided with locating means locating at least one of the devices in position.

Fuel supply equipment embodying the invention has the advantage that the unit can be assembled and tested in simple manner before installation in the tank. The installation of the unit in the tank requires little more effort than the assembly of the fuel conveying device alone in the known fuel suoply equipment.

Embodiments of the present invention will now be more particularly described by way of example with reference to the accompanying drawings, in which: Fig. 1 is a schematic view of a motor vehicle engine with associated fuel supply system, including schematically indicated fuel supply equipment embodying the invention; Fig. 2 is a sectional elevation of a first form of unit in such supply equipment; Fig. 3 is a sectional elevation of a second form of unit in such supply equipment; Fig. 4 is a sectional elevation of a third form of unit in such supply equipment; Fig. 5 is a sectional elevation of a fourth form of unit in such a supply equipment; Fig. 6 is a detail view of a variant of the unit of Fig.

5; Fig. 7 is a sectional elevation of fifth form of unit in such supply equipment; Fig. 8 is a detail view of a variant of the unit of Fig. 6; Fig. 9 is a sectional elevation of sixth form of unit in such supply equipment; Fig. 10 is a sectional elevation of seventh form of unit in such supply equipment; and Fig. 11 is a sectional elevation of eighth form of unit in such a supply equipment Referring now to the drawings there is shown in Fig. 1 a fuel supply system in which fuel, which is to be fed to an internal combustion engine 12 of a motor vehicle, is stored in a fuel tank 10. A unit 14, which comprises a fuel conveying device 17, which by way of a pump inducts the fuel through a suction stub pipe 16 and then conveys it through a pressure duct 18 to the engine 12, is disposed in the tank 10.

As Fig. 2 shows, the unit 14 comprises a synthetic material carrier element 20, at which locating means for individual components of the unit are arranged. Thus, the carrier element 20 has a central pipe portion 22, which serves as mounting for the fuel conveying device 17. The fuel conveying device 17 comprises a pump part and a motor part. The motor part serves as an electric drive motor 26 for a pump 24 of the conveying part. When the motor 26 is actuated and the pump rotor of the pump 24 rotates, this inducts fuel in the direction of the arrow 28 and urges this through a housing of the device 17 until the fuel issues from a pressure outlet 30. The pipe portion 22 is surrounded by an annular pot 32, the base 34 of which is connected with the pipe portion 22. The wall of the pipe portion 22 thus forms the inner wall of the annular pot 32.The outer wall 36, which is also integrally connected with the base 34, of the annular pot 32 projects upwardly beyond the pipe portion 22 so that its end face 38 remote from the base 34 forms a support for a unit lid 40. The unit lid 40 closes the pot 32.

Since the fuel conveying device 17 seated in the pipe portion 22 tightly closes the pipe portion 22, the annular pot 32 has a rising duct 42 which is conductively connected near the base 34 with the pot 32. The rising duct 42 is provided at its free end with a pressure stub pipe 44, in which a non-return valve 46 is accommodated. The pressure duct 18 illustrated in Fig. 1 is connected to the stub pipe 44. in addition, a passage 48 for electrical supply cables 50 of the motor 26 and an excess pressure valve 52 are provided in the lid 40. An annular filter Sa is placed in the annular space of the pot 32.When the fuel to be conveyed leaves the pressure outlet 30 of the fuel conveying device 17, it is initially disposed in the region of the lid 40 and then flows through the filter 54 in the direction of the arrows 56 until it collects in the region of the pot base 34 and passes from there into the rising duct 42 and thereafter into the duct 18. The unit 14 is connected by way of appropriate mountings 58 and vibration dampers 60 fastened thereto with a wall of the tank 10. The excess pressure valve 52 protects the pot-shaped carrier element against damage which could arise due to undesirably high internal pressure build-up.

In the following embodiments,those elements of the unit which correspond to elements described above by reference to Fig. 2, are provided with the same reference numerals or numerals with a distinguishing first digit.

In the embodiment shown in Fig. 3, the unit 114 likewise comprises a plastics material carrier element 120. In the case of the carrier element 120, the pot base 134 also closes one end of a pipe portion 122. In the region of the pipe portion 122, the base 134 is reinforced so that a chamber 136 for an impeller wheel 138 of a conveying pump 124 can be formed therein. A chamber cover 140 with a suction stub pipe 16 closes the chamber 136 at the suction side. Arranged in the now thus formed niche-like pipe portion 122 is a pre-assembled electrical drive motor 142, an armature shaft 144 of which is connected, secure against rotation, with the impeller wheel 138 of the pump 124. In this embodiment, too, a unit lid 40 is provided, which closes the annular pot 32 and the pipe portion 122.The lid 40 is similarly penetrated by supply cables 50 for the motor 142. Equally, it includes an excess pressure valve 52.

Finally, a fuel filter 54 is accommodated in the annular interior space of the pot 32 and a rising duct 42 with a non-rerurn valve 46 is connected near the pot base 134 with the annular space of the annular pot 32. Again, the carrier element 120 is provided with mountings 58 and vibration dampers 60, by way of which it can be fastened in the tank 10. In operation of the unit 114, the pump 124 inducts fuel by way of the suction stub pipe 16 and urges this by way of a pressure outlet 130 in the base 134 into a niche-like space 146 beside the wall of the pipe portion 122. The motor 1 & is cooled - by flow either therethrough or therearound - by the fuel, and the fuel then flows through the filter 54 in the direction of the arrows 156 and thereafter passes by way of the rising duct 42 and the non-return valve 46 into the duct 18.

In the unit 214 illustrated in Fig. 4, a fuel conveying device 17 as described in Fig. 2 is accommodated within a plastics material carrier element 220. However, no pipe portion is provided for the mounting of the device 17 in this embodiment. Instead, the carrier element base 234 has a central passage 236, through which the suction stub pipe 16 projects into the tank. At the rim of the passage 236, the base 234 has an annular collar 240, which projects inwardly into the pot-shaped carrier element 20 and serves for centring a first resilient damping ring 242. The damping ring 242 has an annular cut-out 244, in which the pump part 2a of the fuel conveying device 17 sits and thereby centres the fuel conveying device 17.In addition, the damping ring 242 is firmly connected with a carrier part 246, on which a filter 254 which surrounds the device 17, is seated. Connected to the end of the filter 254 remote from the damping ring 242 is a second rigid carrier ring 248, to which a second damping ring 250 is fastened. The second damping ring 250, too, has a centring cut-out 252 for the fuel conveying device 17. Through this described construction, the device 17 is centred relative to the carrier element 220 and the filter 254 is also held in correct position with respect to the device 17. The damping elements 242 and 250 ensure low-noise running of the device 17.In this case, too, the substantiasly pot-shaped carrier element 220 is provided with a lid 240, which has a passage for the electrical connections 50 of the electrical motor of the fuel conveying device 17. Equally, an excess pressure valve 52 is present. As in the case of the already described embodiments, the carrier element 220 also has a rising duct 42 with a non-return valve 46. The rising duct 42 is connected near to the pot base 234 with the interior space of the carrier element 220. When the device 17 is operating and inducts fuel through the stub pipe 16, this fuel flows through the device 17 and issues out of this above the filter 254. The fuel then follows the arrows 256, flows through the filter 254 and leaves the unit 214 by way of the rising duct 42 and the non-return valve 46, from where it passes into the pressure duct 18.

In the embodiment shown in Fig. 5, the fuel conveying device 317 is provided with a two-stage pump. Thus, a first conveying element 324 is fastened, secure against rotation, to the free end 328 of an armature shaft 322 of the electrical drive motor. The conveying element rotates in a pumo chamber 326, which is formed by a cut-out in the base 334 of a pot-shaped plastics material carrier element 320. This chamber, too, is closed by a cover 336. A second pump stage 340 is integrated into the housing of the device 317 in similar manner to that described for the embodiments of Figs. 2 and 4.The first pump stage 318 with the conveying element 324 inducts fuel by way of a suction opening 319 in the cover 336 and urges this by way of a pressure outlet 321 in the direction of the arrow 323 into a rising duct 325, from where it passes by way of a passage 327 in the wall 329 of the carrier element 320 into the interior space of the carrier element. Arranged therein, as for the other embodiments, is an annular or tubular filter 354, which completely surrounds the device 317. The fuel issuing from the rising duct 325 following the arrow 323, then flows through the filter 354 and passes, following the arrow 341, into the second pump stage 340, where it flows througn the device 317 and then by way of a pressure stub pipe 344 into the pressure duct 18.The unit lid 3a0 is in this case provided with a central cut-out 342 and so constructed that it assures a clean centring of the device 317. A pipe portion 346, which serves for the mounting of a pressure regulator 348, is also provided at the lid 340. The pressure space 350 of the pressure chamber 348 is connected by way of appropriate pipe connections 352 and 353 with the pressure duct 18 or with the interior soace of the carrier element 320.

In this embodiment, an adequate quantity of fuel, which is supplied by the first pump stage or preliminary stage 318 and degasifies while stored in the carrier element 320, is always available to the second pump stage or pressure stage 340.

The embodiment shown in Fig. 6 essentially corresponds to that of Fig. 5, but in the embodiment of Fig. 6 a return duct (not illustrated) by way of which the fuel not needed by the engine 12 is led back again to the unit 314, is connected to the pipe portion 346 in place of the pressure regulator 348.

In the embodiment of Fig. 7, the plastics material carrier element 420 for the unit 414 is constructed in pot shape. The unit lid 440 has a central cut-out, by which a fuel conveying device 417 engaging therethrough is centred. In this case, too, the device 417 is surrounded by an annular or tubular filter 454. The filter sits on a plate-shaped carrier 455, which has a convexity 456 engaged in a depression 457 in the pot base 434 and centred therein. Near to the pot base 434, the pot wall of the carrier element 420 is penetrated by an inflow opening 460 of a nozzle 462, which cooperates with a feed duct 464 in the sense of a jet pump. The jet pump 460, 462 and 464 serves for the filling of the carrier element 420, since the stub pipe 416 of the device 417 opens within the substantially closed carrier element 420.The device 417 is thus capable only of inducting fuel already situated in the carrier element. In order to ensure first-time filling of the carrier element, a first-time filling valve 466, which is constructed as a non-return valve, is arranged in the pot base 434. This valve 466 opens when fuel is filled into the tank 10, but the carrier element 420 is still filled with air. A pressure which brings the valve 666 into its open setting illustrated in Fig. 7 is then present at a plate-shaped closure member 468 of the valve 466 by way of inflow openings 470 in the pot base 434. The carrier element 420 now fills by way of the inflow openings 470, according to the level of fuel in the tank 10. The fuel conveying device 417 can then induct fuel and supply the engine 12 by way of the stub pipe 444. The jet pump serves for the continuing filling of the carrier element 20. This jet pump is operated either by the excess fuel (arrow 472) flowing back in a duct 473 from the engine or by a branch flow (arrow 474) taken from the pressure side of the device 417 or from the pressure duct 18. It is essential in that case that the jet pump is situated below the fuel level in the tank 10 so that the fuel flow (arrow 477) fed to the nozzle 462 entrains further fuel from the tank 0 and provides orderly filling of the carrier element 420.

The embodiment illustrated in Fig. 8 corresponds substantially to the just described construction. However, a pressure regulator 448, the arrangement of which corresponds to that of the pressure regulator 348 in Fig. 5, is provided in Fig. 8. However, in this construction the fuel (arrow 451) flowing out of a pressure space 450 of the pressure regulator 448 is fed by way of a branch duct 480 to the jet pump from where it passes by way of a rising duct 482 into the space of the carrier element 420 (see also the arrows 484 in Figs. 7 and 8). From there, the fuel conveying device 417 inducts the fuel (arrows 485) and leads this to the engine 12.

By contrast to the embodiments described so far, in which the fuel conveying device is always arranged within the carrier element, the fuel conveying device in the units of Figs. 9, 10 and 11 is disposed in mountings which are arranged outside the carrier element, but firmly connected therewith.

Thus, the arrangement according to Fig. 9 comprises a carrier element 520 with a pot-shaped receptacle 521, in which a filter 554 is arranged. A mounting 55, which has the form of a niche or pot, for an electrical drive motor 526 is arranged at the pot wall of the carrier element 520. The interior space of the pot and the interior space of the niche are closed by a common unit lid 540. Electrical connections 550 for the motor 526, as well as a non-return valve 546 and an excess pressure valve 552, are provided in the lid 540. The valve 552 is connected by way of a connecting duct 553 with the mounting space for the motor. The non-return valve 546 is accommodated in the pressure stub pipe 544, to which the pressure duct 18 is connected.A conveying pump 524 is accommodated - as in the embodiment according to Fig. 3 - in the pot base 534, which is constructed to be thickened in the region of the niche-shaped mounting 555 for the motor 526. An impeller wheel 538 of the pump 524 is arranged in a chamber-shaped cut-out 536, which is closed by a cover 540. In operation of the unit 514, the pump 524 inducts fuel by way of the stub pipe 16 and urges this through the mounting 555, from where the fuel passes, according to the arrow 525, by way of a passage 530 to the pot-shaped receptacle for the filter 554.

From there the fuel, after flowing through the filter,passes out of its central region - according to the arrows 535 - and into the pressure stub pipe to lead onto the pressure duct 18.

The foregoing description applies equally to the niche-shaped cut-out for the electrical motor 626 in the unit SId according to Fig. 10. In departure from the described embodiment, however, the receptacle pot 655 for the filter 654 is so arranged that the nicheshaped mounting for the electrical motor 626 is disposed at the pot base 634 of the filter receptacle pot 655. A lid 640 of the filter receptacle pot is thus disposed on that side of the filter receptacle pot which is remote from the motor 26. This, too has a pressure stub pipe 644 with a non-return valve 646. The nicheshaped receptacle 655 for the motor 626 has a separate niche lid 660, which is penetrated by electrical connections 650 of the motor 626. In addition, an excess pressure valve 652 is arranged in the lid 660.In operation of the unit 614, a pump 624 driven by the motor 626 inducts fuel through the stub pipe and then urges this by way of a passage 630, according to the arrows 625, into the rim region of the receptacle pot 655. After flowing through the filter 654, the fuel issues by way of the pressure stub pipe 644 arranged centrally in the lid 640 and thereafter passes into the pressure duct 18.

The embodiment, shown in Fig. 11 differs from the JUst described constructions in that the plastics material carrier element 720 of the unit 714 has a receptacle pot 721 for a filter 754, at the base 734 of which a beaker-shaped receptacle 735 is so arranged that the receptacle base and the pot base 234 are formed by a common wall 734. The receptacle 735 is integrally connected with the receptacle pot 721. A fuel passage opening 736 is arranged in the common base 734. The receptacle 735 contains an electrical motor 7a0 as well as also a conveying pump 724. Fuel inducted by the pump enters by way of the suction stub pipe 16 into the conveying pump 724 and passes from this into the interior space of the receptacle 735 and flows through the motor 72a.From there, the fuel passes, according to the arrow 745, into the filter receptacle pot 721, flows through the filter 754 and then issues from this, according to the arrows 750, through a pressure stub pipe 74a, in which a non-return valve 746 is arranged and to which the pressure duct 18 is connected. The stub pipe 744 is moulded on a lid 760, which also has an excess pressure valve 752 and closes the receptacle pot 721 for the filter 754. In this embodiment, the filter 754 is arranged on an apertured carrier 765, which is centred within the pot 721. Tn this embodiment, mountings 758 and vibration dampers 761 are provided at the receptacle 735 for the motor 7a0.

It is common to all embodiments that the equipment for the supply of the internal combustion engine of a motor vehicle with fuel present in a storage tank comorises a unit with a carrier element at which mountings for the unit components are arranged.

These unit components can be formed by a filter, an electrical drive motor and/or a conveying pump, a pressure regulator and so forth.

Claims

1. Fuel supply equipment for a vehicle fuel supply system, comprising a fuel tank and a unit which is arranged in the tank and comprises a carrier element, a fuel conveying device for conveying fuel out of the tank and at least one device for influencing such fuel or a flow thereof before or after conveying by the conveying device, the carrier element being provided with locating means locating at least one of the devices in position.

2. Equipment as claimed in claim 1, wherein the carrier element comprises plastics material.

3. Equipment as claimed in claim 1 or claim 2, the locating means defining a recess receiving the at least one device.

4. Equipment as claimed in any one of the preceding claims, the locating means comprising a stub pipe.

5. Equipment as claimed in any one of the preceding claims, the locating means comprising a tubular member.

6. Equipment as claimed in claim 1 or claim 2, wherein the at least one device is a fuel filter and the carrier element has a potshaped recess receiving the filter.

7. Equipment as claimed in claim 6, wherein the carrier element has a beaker-shaped recess receiving a component or components of the fuel conveying device.

8. Equipment as claimed in claim 6, wherein the carrier element has a beaker-shaped recess receiving the fuel-conveying device.

9. Equipment as claimed in claim 7 or claim 8, wherein the beaker-shaped recess is disposed in the pot-shaped recess, the fuel filter being annular and disposed to surround the beaker-shaped recess.

10. Equipment as claimed in claim 7 or claim 8, wherein the beaker-shaped recess is disposed at one side of the pot-shaped recess.

11. Equipment as claimed in any one of claims 7 to 10, wherein the beaker-shaped recess is connected to the pot-shaped recess by way of an overflow passage.

12. Equipment as claimed in any one of the claims 7 to 11, wherein the recesses are closed by a common cover member.

13. A motor vehicle provided with fuel supply equipment as claimed in any one of the preceding claims.

13. Equipment as claimed in any one of claims 7 to 11, wherein the recesses are closed by separatecover members.

14. Equipment as claimed in claim 7, wherein a drive motor of the fuel-conveying device is arranged in the beaker-shaped recess and the carrier element further has a pump chamber receiving a rotatable conveying member drivingly coupled to the motor, the pump chamber being closed by a closure member.

15. Equipment as claimed in claim 14, wherein the closure member has an inflow opening for the flow of fuel into the pump chamber.

16. Equipment as claimed in claim 12, wherein the cover member closing the pot-shaped recess has an outlet stub pipe.

17. Equipment as claimed in any one of claims 6 to 15, wherein the unit comprises an outlet stub pipe communicating with the pot-shaped recess.

18. Equipment as claimed in any one of claims 6 to 15, wherein the unit comprises an inlet which communicates with the pot-shaped recess and is connected to a fuel return duct.

19. Equipment as claimed in any one of claims 6 to 15, wherein the unit comprises a stub pipe which communicates with ;he pot-shaped recess and is connected to a pressure regulator.

20. Equipment as claimed in any one of claims 6 to 9, wherein the fuel-conveying device comprises a first pump stage arranged to induct fuel from the tank by way of an inflow opening of the unit and to discharge the fuel into the pot-shaped recess and a second pump stage arranged to induct fuel from the pot-shaped recess and to discharge the fuel by way of an outflow opening of the unit.

21. Equipment as claimed in claim 20, wherein the unit has a rising duct connected to an outlet of the first pumo stage and to an inlet of the pot-shaped recess in the region of an uppermost portion of the filter.

22. Equipment as claimed in claim 1, wherein the at least one device is a tubular fuel filter provided at each end thereof with a support ring provided at its inner circumference with a resilient damping ring, the fuel-conveying element being seated in the damping rings and one of the damping rings being fixed to the carrier element.

23. Equipment as claimed in claim 22, wherein the damping rings are secured to the support rings.

24. Equipment as claimed in claim 18, wherein the inlet and a connecting end of the return duct form a jet pump for feed of fuel into the pot-shaped recess in the region of the base of the carrier element.

25. Equipment as claimed in claim 24, wherein the inlet opening communicates with the pot-shaped recess by way of a rising duct.

26. Equipment as claimed in claim 24 or claim 25, wherein the carrier element is provided in its base with a non-return valve which opens when the level of fuel in the tank is hiaher than that of fuel in the pot-shaped recess and closes when the level of fuel in the tank is lower than that of fuel in the pot-shaped recess.

27. Equipment as claimed in any one of claims 6 to 21, wherein the base of the carrier element has a central depression and the filter has a base plate with a protrusion so engaged in the depression as to centre the filter in the pot-shaped recess.

28. Equipment as claimed in any one of claims 7 to 11,. wherein the carrier element comprises means defining the pot-shaped recess, means defining the beaker-shaped recess and means closing the recesses.

29. Equipment as claimed in any one of the preceding claims, wherein the unit is fastened to a wall of the tank by way of vibration damping means arranged between the wall and the carrier element.

30. Fuel supply equipment substantially as hereinbefore described with reference to any one of Figs. 2 to 11 of the accompanying drawings.

31. A motor vehicle provided with fuel supply equipment as claii?ied in any one of the preceding claims.

32. A fuel pumping and filtering unit comprising a housing mountable in a vehicle fuel tank and provided with an inlet and an outlet, a fuel pump arranged in the housing and operable to pump a flow of fuel through the housing in direction from the inlet to the outlet, and a filter arranged in the housing and arranged to filter the fuel flow upstream or downstream of the pump with respect to the flow direction, the housing comprising a carrier element provided with locating means locating at leastoneof the pumpand the filter in position and closure means closing the carrier element.

Amendments to the claims have been filed as follows 1. Fuel supply equipment for a vehicle supply system, comprising a fuel tank and a unit which is arranged in the tank and comprises a carrier element, a fuel conveying device for conveying fuel out of the tank and an annular fuel filter for filtering fuel before or after conveying by the conveying device, the carrier element being provided with a potshaped recess receiving the filter and within the pot-shaped recess with a beaker-shaped recess which receives the fuel conveying device,wherein the pot-shaped recess annularly surrounds the fuel conveying device and the unit has an inlet which communicates with the pot-shaped recess and with a fuel return duct, the inlet and a connecting end of the return duct forming a jet pump for feed of fuel into the pot-shaped recess in the region of a base of the carrier element.

3. Equipment as claimed in claim 1 or claim 2, wherein the carrier element is provided with a stub pipe.

4. Equipment as claimed in any one of the preceding claims, wherein the carrier member is provided with a tubular member.

5. Equipment as claimed in any one of the preceding claims, wherein the recesses are closed by a common cover member.

6. Equipment as claimed in any one of claims 1 to 4, wherein the recesses are closed by separate cover members.

7. Equipment as claimed in claim 5, wherein the cover member closing the pot-shaped recess has an outlet stub pipe.

8. Equipment as claimed in any one of claims 1 to 9, wherein the unit comprises a stub pipe which communicates with the pot-shaped recess and is connected to a pressure regulator.

9. Equipment as claimed in any one of the preceding claims, wherein the inlet communicates with the pot-shaped recess by way of a rising duct.

10. Equipment as claimed in any one of the preceding claims, wherein the base of the carrier element has a central depression and the filter has a base plate with a protrusion so engaged in the depression as to centre the filter in the pot-shaped recess.

11. Equipment as claimed in any one of the preceding claims, wherein the unit is fastened to a wall of the tank by way of vibration damping means arranged between the wall and the carrier element.

12. Fuel supply equipment substantially as hereinbefore described with reference to Figs. 7 and 8 of the accompanying drawings.