GB2533364A

GB2533364A - In-tank pump module with labyrinth on inlet

Info

Publication number: GB2533364A
Application number: GB1422556.9A
Authority: GB
Inventors: De Biasio Ennio; Robin Jean-François; Bungartz Gerhard
Original assignee: Delphi Automotive Systems Luxembourg SA
Current assignee: BorgWarner Luxembourg Automotive Systems SA
Priority date: 2014-12-18
Filing date: 2014-12-18
Publication date: 2016-06-22

Abstract

An in-tank fuel pump module reservoir 18 adapted to be immersed inside a tank (10, fig.1) containing a fluid such as fuel. The reservoir 18 is divided by an internal wall 40 in a first compartment 42 and a second compartment 44 adapted to receive a fuel pump (14, fig.2). The reservoir 18 is further provided with partitioning walls 52 arranged inside the first compartment 42, said partitioning walls forming a labyrinth, maze or tortuous path followed by the flow of the liquid between the inlet orifice (38, fig.2) and the inner transfer passage (72, fig.4) so that, contaminant particles present in the fuel may be retained in order to protect the pump (14). Preferably the partitioning walls (52, 54, 62, fig.4) are substantially parallel to each other extending between a bottom wall (56, fig.4) and an opposed top face (60, fig.4), the partitioning walls driving the flow into opposed down-and-up directions.

Description

In-tank pump module with labyrinth on inlet

TECHNICAL FIELD

The present invention relates generally to the reservoir of a pump module, said reservoir comprising a partitioned compartment enabling to trap and retain particle contaminants.

BACKGROUND OF THE INVENTION

Fuel injection systems of a vehicle engine are generally provided with an in-tank pump module aiming at taking fuel in a low pressure tank and flowing it at a few bars toward the engine. The pump module comprises a low pressure pump that requires to be at least partially immersed in the fuel. To achieve this independently of the fuel level in the tank, the pump module comprises its own reservoir, shaped as a bowl, and in which is arranged the pump. Fuel is sucked from the bottom of the tank into a first compartment of the pump module reservoir, wherefrom it transfers into a second compartment where it is pumped and flown toward the engine. The first compartment aims at segregating particle contaminants that may be present in the fuel, and retain said particles at the bottom of the first compartment. This has proven some efficiency but, as more stringent level of fuel de-contamination is required said efficiency is no longer sufficient.

SUMMARY OF THE INVENTION

It is the intention of this invention to propose a way to resolve, or at least to mitigate, the above mentioned problem by proposing an in-tank fuel pump module reservoir adapted to be immersed inside a tank containing a fluid such as fuel F. The reservoir has peripheral walls defining an internal volume divided by an internal wall in a first compartment and a second compartment adapted to receive a fuel pump. The reservoir is provided with: - an inlet orifice arranged through a bottom peripheral wall and adapted to enable fuel to flow inside the first compartment, - an inner transfer passage arranged through the internal wall and adapted to enable fuel to flow from the first compartment to the second compartment and, -an outlet orifice arranged through a peripheral wall and adapted to enable fuel pressurized by the pump to flow outside the pump module toward a fuel consuming device.

The reservoir is further provided with partitioning walls arranged inside the first compartment, said partitioning walls forming a labyrinth followed by the flow between the inlet orifice and the inner transfer passage so that. contaminant particles present in the fuel may be retained in order to protect the pump.

The partitioning walls form a plurality of chambers in fluid connection with each other creating obstacles to the flow forcing it to change direction.

The partitioning walls are substantially parallel to each other extending between a bottom wall that is the lower most peripheral wall of the reservoir and an opposed top face. The partitioning walls drive the flow into opposed downand-up directions.

The reservoir is provided with separating partitioning walls upwardly extending from the bottom wall of the reservoir to a top extremity that is in the vicinity to the top face and with at least one other partitioning wall downwardly extending inside a chamber, from the top face toward a bottom extremity that is in the vicinity to the bottom face so that, the fluid inside said chamber flows downwardly then upwardly prior to exit said chamber.

More particularly, each of the chambers is partitioned by a downwardly extending partitioning wall.

Furthermore, the reservoir comprises a plurality of small ribs arranged inside at least one of the chambers and upwardly protruding from the bottom wall, said ribs creating further obstacles adapted to retain particle contaminants present in the flow.

The invention also extends to an in-tank fuel pump module comprising a reservoir as described in the above paragraphs.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention is now described by way of example with reference to the accompanying drawings in which: Figure 1 is a general representation of a low pressure tank within which is arranged a pump module as per the invention.

- Figure 2 is an exploded view of the pump module of figure 1.

- Figure 3 is top view of the reservoir of the pump module of figure 2.

- Figure 4 is a representation of a labyrinth followed by a fuel flow inside the pump module of figures 1 and 2.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

In reference to figure 1 is represented a low pressure fuel tank 10 in which is arranged a pump module 12, detailed in the exploded figure 2, adapted to be immersed in the fluid F contained in the tank 10. The pump module 12 aims at maintaining an operational fuel level for a pump 14 that sucks the fuel F and flows it toward an internal combustion engine 16 or any type of fuel consuming device. In a vehicle fuel injection system the pump 14 is identified by professionals as the low pressure pump.

To achieve this objective the pump module 12 comprises a reservoir 18 that has the shape of a bowl, said reservoir 18 defining an internal volume V in which is placed the pump 14. The reservoir 18 comprises peripheral wall 20 and, it is closed by a cover plate 22, 36. A jet pump 24 fixed over an inlet opening provided under the reservoir 18 fills it up to maintain inside the reservoir 18 said operational level of fuel F. Terms such as "under, above, top, bottom... are utilized in the reference to the general orientation of figure 1 which is the orientation when the system is at rest.

The pump 14 is protected from particle contaminants present in the fuel F by a strainer assembly 26 arranged over the inlet 28 of the pump 14. At the outlet 30 of the pump 14, which is the outlet of the pump module, the fuel F flows at a few bars pressure via specific conduits towards the engine 16. In the reservoir are also arranged further well-known components such as a fuel level sensor 32 or one-way check valves 34 which are not detailed any further.

In reference to figure 2, the pump 14 is placed in a pump holder 36 on which the strainer assembly 26 is firmly clipped. This assembly is fixed under the cover plate 22 which holds, in a specific sealed compartment, an electronic control unit that controls the operation of the pump module 12. Alternatively, the electronic unit may be arranged in another location remote from the module.

Arranged over the reservoir 18, the cover plate 22 closes the pump module 12. The jet pump 24 is fixed over an inlet opening 38 provided under the reservoir 18. In the embodiment of figure 2, the level sensor 32 is fixed outside of the reservoir 18.

The reservoir 18 comprises an internal wall 40 that divides the internal volume V into a small first compartment 42 and a large second compartment 44 adapted to receive the pump N. As better visible on the top view of figure 3, although multiple alternative embodiments are made, the first compartment 42 is confined on a side of the reservoir 14 and it extends along a peripheral wall, from an inlet side 46 to a transfer side 48. On the inlet side 46 a conduit 50 upwardly extends from the jet pump 24 and the inlet opening 38 to deliver fuel F from the top of the first compartment 42. Furthermore, a plurality of partitioning walls 52 substantially parallel to each other vertically extend in the first compartment 42 from the inlet side 46 to the transfer side 48. On figure 3 the transvers trace of said partitioning walls 52 is observable and, as shown, some of said walls may be plane while others comprise two, or more, planes. This configuration depends upon the shape of the peripheral wall of the reservoir 18 which in the present case comprises a flat portion followed by a circular portion.

In figure 4 a portion of the peripheral wall 20 of the reservoir 14 has been removed enabling to show the inside of the reservoir 14 and to detail the first 42.

As visible, the partitioning walls 52 extend only partially over the height of the first compartment 42. The partitioning walls 52 are alternately arranged as upwardly extending walls 54 fixed to the bottom peripheral wall 56 and extending up to a distant top extremity 58 that is close to a top face 60 and, downwardly extending walls 62 fixed to said top face 60 and extending to a distant bottom extremity 64 that is close to the bottom peripheral wall 56.

An exemplary embodiment and the flow path associated.

The inlet side 46 is represented on the right of the figure where the conduit 50, which is as a reservoir for the jet pump 24, is. In the middle of the first compartment 42 is arranged a central upwardly extending wall 54 that divides the first compartment 42 into a first chamber 66, on the right of the figure, and a second chamber 68, on the left. As said priory, the top extremity 58 of the central upwardly extending wall 54 is at a distance of the top face 60. In the middle of each chamber 66, 68, is arranged a downwardly extending partitioning wall 62 and, as said priory the bottom extremity 64 of said wall 62 is at a distance from the bottom wall 56. Furthermore, inside each of the chambers 66, 68, upwardly protrude from the bottom peripheral wall 56 two small ribs 70, the height of said ribs 70 being smaller than the distance from the bottom extremity 64 of the downward walls 62 to the bottom wall 56. Alternatively, any number of ribs 70 may be arranged at the bottom of the chambers.

The flow path inside the first compartment 42is now detailed. It follows the arrows Al-A9 shown on the figure and so, from the jet pump 24, the fuel F upwardly flows Al in the conduit 50 then it downwardly flows A2 in the channel limited by the proximal downward wall 62, prior going under A3 said wall 62 and moving upward A4 in another channel limited by the central upward wall 54. Then, the fuel F exits the first chamber 66 by going over AS said central wall 54 and it continues by following in the second chamber 68 a similar down-and-up path A6-A9 as in the first chamber 66. When reaching the end of the last channel, the fuel F exits the first compartment 66 and transfers into the second compartment 44 via a transfer passage 72 arranged on the top of the transfer side 48 of the internal wall 40. The alternate partitioning walls 54, 62, and the small ribs 70 create a labyrinth 74 for the fuel flow. In said labyrinth the particle contaminants present in the fuel F are trapped and retained at the bottom of the chambers 66, 68, and remain between the ribs 70.

The person skilled in the art of pump modules will know how to extend the labyrinth 74 of the present embodiment to alternative embodiments such as comprising more than two chambers.

From a manufacturing stand point, the reservoir 18 is known to be plastic molded and, the partitioning walls 52 and ribs 70 are integrally molded with the reservoir. A non-integral alternative wherein the partitioning walls are individually arranged, or even the complete labyrinth is arranged separately is possible.

LIST OF REFERENCES

F fuel V internal volume Al-A9 fluid flow fuel tank 12 pump module 14 pump 16 engine 18 reservoir peripheral walls 22 cover plate 24 jet pump 26 strainer assembly 28 inlet outlet 32 level sensor 34 check valve 36 pump holder 38 inlet opening of the reservoir internal wall 42 first compartment 44 second compartment 46 inlet side of the first compartment 48 transfer side conduit 52 partitioning walls 54 upwardly extending partitioning walls 56 bottom peripheral wall 58 top extremity of a partitioning wall top face of the first compartment 62 downwardly extending partitioning walls 64 bottom extremity of a partitioning wall 66 first chamber 68 second chamber small ribs 72 transfer passage 74 labyrinth

Claims

CLAIMS1. In-tank fuel pump module reservoir (18) adapted to be immersed inside a tank (10) containing a fluid such as fuel (F), the reservoir (18) having peripheral walls (20) defining an internal volume (V) divided by an internal wall (40) in a first compartment (42) and a second compartment (44) adapted to receive a fuel pump (14), the reservoir (18) being provided with: - an inlet orifice (38) arranged through a bottom peripheral wall and adapted to enable fuel to flow inside the first compartment (42), -an inner transfer passage (72) arranged through the internal wall (40) and adapted to enable fuel to flow from the first compartment (42) to the second compartment (44) and, - an outlet orifice (30) arranged through a peripheral wall and adapted to enable fuel pressurized by the pump (14) to flow outside the pump module (12) toward a fuel consuming device (16), characterized in that the reservoir (18) is further provided with partitioning walls (52, 54, 62) arranged inside the first compartment (42), said partitioning walls (52) forming a labyrinth (74) followed by the flow (Al-A9) between the inlet orifice (38) and the inner transfer passage (72) so that, contaminant particles present in the fuel may be retained in order to protect the pump (14).
2. Reservoir (18) as claimed in claim 1 wherein said partitioning walls (52, 54, 62) form a plurality of chambers (66, 68) in fluid connection with each other creating obstacles to the flow forcing it to change direction.
3. Reservoir (18) as claimed in claim 2, wherein the partitioning walls (52, 54, 62) are substantially parallel to each other extending between a bottom wall (56) that is the lower most peripheral wall (20) of the reservoir (18) and an opposed top face (60), said partitioning walls (52, 54, 62) driving the flow into opposed down-and-up directions.
4. Reservoir (18) as claimed in claim 3 wherein the chambers (66, 68) separating partitioning walls (54) upwardly extends from the bottom wall (56) of the reservoir (18) to a top extremity (58) that is in the vicinity to the top face (60), and wherein the reservoir (18) is further provided with at least one other partitioning wall (62) downwardly extending inside a chamber (66, 68) from the top face (60) toward a bottom extremity (64) that is in the vicinity to the bottom face (60) so that, the fluid inside said chamber flows downwardly then upwardly prior to exit said chamber.
5. Reservoir (18) as claimed in claim 4 wherein each of the chambers (66, 68) is partitioned by a downwardly extending partitioning wall (62). 10
6. Reservoir (18) as claimed in any one of the claims 3 to 5 further comprising a plurality of small ribs (70) arranged inside at least one of the chambers (66, 68) and upwardly protruding from the bottom wall (56), said ribs (70) creating further obstacles adapted to retain particle contaminants present in the flow.
7. In-tank fuel pump module (12) comprising a reservoir (18) as claimed in any one of the preceding claims.