Title of Invention

'DEVICE FOR REDUCTION OF SURGE NOISES IN A FUEL TANK'

Abstract Guiding elements (9-11) and baffles (4) are positioned inside the fuel tank (1) of an engine-driven vehicle; they deflect a flow of the fuel in a low angle against a wall (3) of the fuel tank (1). This reduces surge noises caused by the fuel. The baffles (4) form a channel (5) with a calming area (6), in which the flow of fuel is throttled (reduced).
Full Text Description
Device for reduction of surge noises in a fuel tank
The invention comprises a device for reduction of surge noises in the fuel tank of an engine-driven vehicle with damping elements arranged in the fuel tank.
Such devices are frequently used, for example, in racing cars and are thus known. In these cases, the damping elements are frequently configured as surge plates arranged in the interior of the fuel tank. The surge plates divide the fuel tank into several chambers. Fuel accelerated in the direction of one wall of the fuel tank first flows around a surge plate placed in front of the wall before it flows against the wall.
The disadvantage of the known fuel tank configuration is that disturbing surge noises result despite the arrangement of the surge plates inside the fuel tank. In the least favourable case, the surge plates in the known device configuration may even

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themselves cause surge noises when fuel sloshes against the surge plates or when the surge plates guide the fuel flow vertically towards the wall of the fuel tank.
The invention addresses the problem of designing a device of the type named at the outset such that it reduces disturbing surge noises to the greatest possible extent.
The invention solves this problem by positioning the damping elements, as guiding elements and/or baffles, at an angle deviating from 90° to guide the flow of the fuel towards the wall of the fuel tank or forming them so as to reduce the speed of the flow.
This configuration prevents right-angled impact of a strong flow. Reduction of the resulting surge noises increases the lower the angle is at which the flow is directed against the wall and the lower the fuel flow speed is. The fuel deflected by the guiding elements or baffles then flows along the wall, causing almost no noise at all. Thus surge noises inside the fuel tank are reduced markedly. Reducing the flow speed of the flow and deflecting it at same time prevents surge noises almost completely.
Fuel flow can be deflected in a desired direction by simple means, due to an advantageous further development of the invention, if the baffles form a channel amongst themselves or together with the floor of the fuel tank. In such a configuration, the baffles are arranged at a low angle to the direction of flow so as to

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avoid disturbing surge noises when the flow hits the baffles.
The flow speed of the fuel is reduced, due to an advantageous further development of the invention, if the channel features a section with a widened cross-section as a calming area. In the simplest configuration, the baffles are positioned with a minimum gap between them and the floor of the fuel tank, rising towards the lateral walls of the fuel tank. The fuel flowing under the baffles is slowed in the calming area and fuel flowing above the baffle is deflected upwards. Other guiding elements intended to deflect the flow can be located, for instance, on the baffles or the floor of the fuel tank.
When the vehicle brakes or accelerates, the resulting surge noises are particularly loud. These surge noises can be reduced particularly well, due to an advantageous further development of the invention, if baffles forming channels are positioned in a front and a rear area of the fuel tank.
The flow rate of the fuel flowing over the baffles is reduced, due to an advantageous further development of the invention, if a funnel-shaped inflow area is positioned before the calming area. The funnel shape also ensures uniform flow into the calming area at different fuel tank filling levels.
The flow speed of the fuel can be further reduced, due to an advantageous further

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development of the invention, if an outflow area with a larger cross-section than that of the calming area is positioned after the calming area.
A contribution to further reduction of the surge noises in the fuel tank is made, due to an advantageous further development of the invention, by positioning the guiding elements on the flow-sided end of the channel.
When the fuel filling level in the tank submerges the baffles, the fuel flowing over the baffles could slosh against the walls of the fuel tank and cause surge noises. It might appear logical to arrange guiding elements on the upper side of the baffles as well in order to guide the fuel flowing over the baffles against the wall at a low angle. However, such additional guiding elements are rendered unnecessary, due to an advantageous further development of the invention, if the guiding elements are given the form of scoop-like blades so as to reverse the direction of flow of the fuel exiting from the channel. Thus the portion of fuel flowing over the baffles is deflected from the fuel which is deflected by the guiding blades used to reverse the flow.
The fuel leaves the calming area at a particularly low speed, due to an advantageous further development of the invention, if at least one of the guiding elements is positioned within the calming area.
The surge noises are particularly low-level, due to an advantageous further development of the invention, if in the calming area a banking-up element is

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positioned essentially at a right angle to the direction of flow. The banking-up element reduces flow speed in the calming area. Additional guiding elements can be positioned so as to guide the previously decelerated flow.
A contribution is made to further reduction of surge noises at varying filling levels in the fuel tank by positioning the baffles at various heights, mainly parallel to the floor of the fuel tank. When the fuel tank is nearly full, the uppermost guiding elements prevent surge noises, whereas the lowest guiding elements deflect the flow so as to reduce noises when the fuel tank is nearly empty.
The flow within the fuel tank is guided in a low angle against the lateral walls of the fuel tank practically free of turbulence, due to an advantageous further development of the invention, if the guiding elements are given a vane-like shape.
Frequently, the directions the flow within the fuel tank will take, thus causing surge noises, cannot be predicted reliably. Surge noises resulting from right-angled contact between the flow and a guiding or banking-up element can be simply reduced, due to an advantageous further development of the invention, if the guiding or banking-up elements are provided with multiple perforations. This design allows part of the fuel hitting the guiding element at right angles to flow through the perforations. This considerably attenuates the impact of the flow. Fuel flow hitting the

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guiding elements with perforations at an angle will however be deflected mainly in the intended direction.
A strong impact of the fuel against the guiding element can be dampened simply, due to an advantageous further development of the invention, if the guiding elements are elastic.
The flow is deflected in accordance with flow intensity, due to an advantageous further development of the invention, if the guiding elements feature an elastic arm to which a guiding vane is attached.
Flow of fuel in a direction that causes surge noises can readily be prevented if the invention device features flap valves to throttle fuel flow in one direction.
The invention device can be produced at particularly low cost if the guiding elements and/or baffles are of a piece with a wall or the floor of the fuel tank. This is particularly advantageous in the case of plastic fuel tanks made by means of the injection moulding method, since the guiding elements and/or baffles can be integrated in the fuel tank at the production stage.
Modern fuel tanks usually feature an opening at the top for insertion of a pumping unit. The guiding elements can easily be placed in such fuel tanks if the guiding elements are designed for insertion through an opening integrated in the wall of the fuel tank. This is of particular advantage in the case of fuel tanks made by means of

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the blowing method, since the guiding elements can be positioned with a high level of reliability following the blowing procedure.
The guiding elements and/or baffles can be fastened inside the fuel tank by means of, for example, bolting or clamping. The guiding elements and/or baffles can, however, be fastened with a particularly high degree of permanence in the fuel tank, due to an advantageous further development of the invention, if they are welded onto the floor or wall of the fuel tank.
The invention allows for numerous different configurations. To further clarify its basic
principle, some of these variant configurations are shown in the accompanying drawing(s) and

described below:
Fig. 1 Channel in a fuel tank, bordered by a baffle,
Fig. 2 Several baffles arranged parallel to one floor of the fuel tank,
Fig. 3 Guiding elements and baffles fastened to the floor of the fuel tank,
Fig. 4 Guiding elements for flow reversal.
Figure 1 shows the lower part of a fuel tank 1 with a floor and lateral wall 3. A baffle 4 is located in the fuel tank 1, which baffle, together with the floor 2, forms a channel 5. The channel, 5, features a calming area 6 with an widened cross-section. An outflow area 7 follows the calming area with a larger cross-section than that of the calming area 6. A funnel-shaped inflow area 8 is positioned upstream from the

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calming area. Guiding elements 9-11 are positioned in the inflow area 8, the calming area 6 and the outflow area 7.
The guiding element 9 positioned in the inflow area 8 features an elastic arm 12, to which is fastened a guiding vane 13. When the fuel flow hits the guiding vane 13, the arm 12 is turned in accordance with the flow rate. This initially dampens the flow and partly deflects it laterally. In the calming area 6, a banking-up element 14 is positioned that throttles the fuel flow rate. The banking-up element 14 features multiple perforations 15 through which fuel flows. The throttled flow is then deflected by the guiding elements 10, 11 in the calming area 6 and outflow area 7 in a low angle against the wall 3 of the fuel tank 1. Fuel flowing over the baffle 4 is deflected upwards by the portion of baffle 4 forming the outflow area 7. This prevents fuel accelerated in the direction of wall 3 of the fuel tank 1 from sloshing against wall 3. The flow direction of the fuel is indicated by arrows in the drawing for purposes of clarification.
Figure 2 shows several baffles 16-19 positioned on top of one another and next to one another in fuel tank 1. The uppermost baffle 16 runs mainly parallel to the floor 2 of the fuel tank 1 and is of a piece with a guiding element 20 pointing downwards at an angle. The middle baffle 17 features an opening 21, through which fuel can flow. The two lower baffles 18, 19 are positioned in a slant from right to left. Fuel flowing

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from right to left thus loses much of its kinetic energy. The throttled flow then meets with a perpendicular guiding element 23 featuring multiple perforations 22. Part of the fuel flows through the perforations 22 of guiding element 23. Most of the flow, however, is deflected by guiding element 23 into the drawing plane. This design throttles the flow at varying fuel filling levels in fuel tank 1, then deflecting it laterally.
Figure 3 shows a channel 26 form by two baffles 24, 25 in a view from above onto the floor 2 of the fuel tank. Two flap valves 27, 28 with vane gates 29, 30 are positioned in the inlet side of channel 26, which valves facilitate flow through channel 26 from left to right as positioned in the drawing. The vane gates 29, 30 open up (i.e. separate) when the fuel flows from right to left until they meet the baffles 24, 25 and close off the channel 26. In the drawing, the vane gates 29, 30 closing off channel 26 are drawn in with dotted lines. Further, two banking-up elements 31, 32 and two vane-shaped guiding elements 33, 34 are positioned in channel 26. The banking-up elements 31, 32 throttle the flow, whereas the guiding elements 33, 34 deflect the flow laterally.
Figure 4 shows a further variant configuration of the invention, in which a channel 37 is formed by two baffles 35, 36 positioned perpendicularly in the floor 2 of the fuel tank 1. At the end of the channel 37, two scoop-like guiding elements 38, 39 are positioned. These guiding elements 38, 39 guide a flow guided through the channel

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37 back along the outside of baffles 35, 36. This deflects fuel flowing along the outside of baffles 35, 36 away from the fuel the flow of which has been reversed by guiding elements 38, 39.

-11-We Claim
1. A device for reduction of surge noises in a fuel tank of an engine driven
vehicle by means of damping elements arranged in the fuel tank,
characterized in that, channel (5, 26, 37) is formed by baffles (4, 16-19,
24, 25, 35, 36) amongst themselves or with a floor (2) of said fuel tank
(1), said baffles and guiding elements (9-11, 20, 33, 34, 38, 39) are
designed for guiding the flow of fuel onto a wall (3) of the fuel tank at an
angle deviating from 90° and for throttling the speed of Flow.
2. A device as claimed in claim 1,
'wherein'
the channel (5) has a larger cross-section than the calming area (6).
3. A device as claimed in any one of the above claims,
'wherein'
baffles (4, 16-19, 24, 25, 35, 36) forming channels (5, 26, 37) in a front and a rear segment of the fuel tank.
4. A device as claimed in any one of the above claims,
'where in'
positioning of a funnel-shaped inflow area (8) upstream from the calming area (6).
5. A device as claimed in any one of the above claims,
'wherein'
positioning of an outflow area (7) with a larger cross-section than that of the calming area (6) downstream from the calming area (6).

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6. A device as claimed in any one of the above claims,
'wheren'
positioning of the guiding elements (11, 23,33, 3, 38, 39) at the flow-side end of the channels (5, 26,37).
7. A device as claimed in any one of the above claims,
'wherein'
giving the guiding elements (38, 39) a scoop-like form so as to reverse the direction of flow of the fuel flowing out of the channel (37).
8. A device as claimed in any one of the above claims,
'where in'
positioning of at least one of the guiding elements (10) in the calming area (6).
9. A device as claimed in any one of the above claims
Vherein'
positioning of a banking-up element (14) in the calming area (6), essentially perpendicular to the direction of flow.
10. A device as claimed in any one of the above claims,
'wherein'
positioning the baffles (16-19) at varying heights and essentially parallel to the floor (2) of the fuel tank (1).
11.A device as claimed in any one of the above claims, wherein there are shaped configuration of the guiding elements (33,34).

-13-
12. A device as claimed in any one of the above claims,
'wherein'
there are muitiple perforations (15, 22) in the guiding elements (23) or banking-up elements (14),
13. A device as claimed in any one of the above claims,
'wherein'
there are elastic guiding elements (9).
14. A device as claimed in any one of the above claims,
therein'
there are guiding elements (9) with an elastic arm (12) and attachment of a guiding vane (13) to the elastic arm (12).
15. A device as claimed in any one of the above claims,
'where in'
flap valves (27,18) are used for throttling a flow of fuel in one direction.
16. A device as claimed in any one of the above claims,
'wherein'
the guiding elements (9-11, 20, 33, 34, 38, 39) and / or baffles (4,16-19, 24, 25, 35, 36) being manufactured of a piece with a wall (3) or floor (2) of the fuel tank (1).

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17. A device as claimed in any one of the above claims, 'wherein'
the guiding elements (9-11, 20, 33, 34, 39) and / or baffles (4,16-19, 24, 25, 35, 36) being fitted with an opening in the wall (3) of the fuel tank (1) for purpose of insertion.
18.A device as claimed in any one of the above claims, wherein the guiding elements (9-11, 20, 33, 34 38, 39) and / or baffles (4, 16-19, 24, 25, 35, 36) being welded to floor 92) or wall 93) of the fuel tank (1).
Guiding elements (9-11) and baffles (4) are positioned inside the fuel tank (1) of an engine-driven vehicle; they deflect a flow of the fuel in a low angle against a wall (3) of the fuel tank (1). This reduces surge noises caused by the fuel. The baffles (4) form a channel (5) with a calming area (6), in which the flow of fuel is throttled (reduced).

Documents:

00132-cal-1998 abstract.pdf

00132-cal-1998 claims.pdf

00132-cal-1998 correspondence.pdf

00132-cal-1998 description(complete).pdf

00132-cal-1998 drawings.pdf

00132-cal-1998 form-1.pdf

00132-cal-1998 form-2.pdf

00132-cal-1998 form-3.pdf

00132-cal-1998 letters patent.pdf

00132-cal-1998 p.a.pdf

00132-cal-1998 priority document others.pdf


Patent Number 203593
Indian Patent Application Number 132/CAL/1998
PG Journal Number 11/2007
Publication Date 16-Mar-2007
Grant Date 16-Mar-2007
Date of Filing 27-Jan-1998
Name of Patentee MANNESMANN VDO AG.
Applicant Address Kruppstrasse 105, D-60388 Frankfurt, Germany
Inventors:
# Inventor's Name Inventor's Address
1 DIETER KELLER Hindemithstrasse 7, 63743 Aschaffenburg, Germany
PCT International Classification Number B 60K 15/077
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 19706658.5 1997-02-20 Germany