EP0616125B1 - Liquid pressuring device in a tank, particularly for the pressurizing of fuel in a vehicle tank - Google Patents

Description

The present invention relates to the field of devices for drawing liquid from a vehicle tank.

The invention applies very particularly but not exclusively to the drawing of fuel from a tank of a motor vehicle.

The invention is however not limited to this particular application. It can for example be applied to the drawing of liquids other than fuel, such as for example the lubricating oil in an engine crankcase. Similarly, the invention is not limited specifically to the field of motor vehicles but can also apply for example to the tank of boats.

More specifically, the invention relates to the field of reservoirs on which a drawing point is very far from an access area.

It is known that on motor vehicles used today, fuel tanks often have a fairly large horizontal surface, generally one or two horizontal dimensions relatively large in relation to the height. These tanks pose delicate problems when drawing water. Indeed, these large surface tanks are very sensitive to the tilt and / or acceleration of the vehicle. The resulting buildup of fuel at one end of the tank can cause the draw-off device to over-prime.

Furthermore, car manufacturers frequently impose a single access zone on the tank, sometimes very off-center with respect to the optimum drawing point.

Numerous devices for drawing fuel from the tanks of motor vehicles have already been proposed.

The document US-A-1866280, published in 1923, describes, for example, an oil drawing system in an engine crankcase comprising a pump centered in the crankcase and comprising two rigid diametrically opposed horizontal conduits. The ducts are connected to the pump by a ball valve system sensitive to the tilt or acceleration of the vehicle. When necessary, the ball automatically closes one of the conduits to prevent the pump from sucking air.

The document US-A-2934077, published in 1960, describes a system equivalent to the document US-A-1866280 cited above. More specifically, document US-A-2934077 describes a drawing assembly comprising a central connection block into which various rigid conduits open which lead to distant drawing points in the tank. The connection between the connection block and the various conduits is controlled by a ring sensitive to the inclination of the tank.

Document DE-A-2505740, published in 1976, describes a drawing system for a fuel tank of a motor vehicle. This system comprises a vertical well centered on the reservoir and provided with a rigid horizontal arm pivotally mounted at the base of the well, around the vertical axis thereof. The horizontal arm communicates with the well and has a suction mouth at its radially outer end.

The document EP-A-0264197, published in 1988, describes a system fairly close to the document US-A-1866280. More specifically, the document EP-A-0264197 describes a drawing device for a vehicle fuel tank comprising a vertical main well placed at a first end of a tank and comprising a drawing mouth at its base. The system also includes a rigid horizontal duct connected to the base of the aforementioned main well and the suction mouth of which is placed near the second end of the tank. The system further comprises means for selectively connecting a pumping system with the mouth provided at the base of the main well at the first end of the reservoir, or with the suction mouth provided at the end of the horizontal rigid duct at the second end of the tank. These selective connection means comprise a movable ball in a housing and sensitive to the accelerations and / or inclination of the vehicle.

The document FR-A-2639405, which is considered to be the closest state of the art, published in 1990, describes another device for drawing fuel from the tank of a motor vehicle. The system described in this document comprises a central well associated with at least two drawing means located in zones distant from each other in the vicinity of the bottom of the tank. The drawing means are connected to a selector placed at the base of the central well. The selector can be actuated as a function of the attitude and the acceleration imposed on the reservoir in order to activate more or less each of the drawing means in order to increase or decrease the flow rate of liquid drawn through this means.

The present invention now aims to improve the existing drawing devices.

The present invention aims in particular to present an economical solution for optimizing the drawing of fuel from a motor vehicle tank.

• une trappe d'accès formée dans la paroi du réservoir,
• un puits généralement vertical fixé sur la paroi du réservoir, au niveau de la trappe d'accès, lequel puits plonge au moins sensiblement jusqu'à la paroi inférieure du réservoir,
• au moins un conduit souple relié par une première extrémité à la base du puits, et qui forme, par sa seconde extrémité, un point de puisage éloigné de la base du puits, et
• un rigidificateur élastique associé au conduit souple pour maintenir fermement celui-ci contre la paroi inférieure du réservoir, au repos, tout en autorisant une déformation du conduit souple lors de l'insertion du dispositif dans le réservoir, par la trappe d'accès.

This object is achieved in the context of the present invention by means of a device for drawing liquid from a tank, in particular drawing fuel from a tank of a motor vehicle, comprising

• an access hatch formed in the wall of the tank,
• a generally vertical well fixed to the wall of the tank, at the access hatch, which well dives at least substantially as far as the bottom wall of the tank,
• at least one flexible conduit connected by a first end to the base of the well, and which forms, by its second end, a point of drawing away from the base of the well, and
• an elastic stiffener associated with the flexible conduit to firmly hold the latter against the bottom wall of the reservoir, at rest, while allowing deformation of the flexible conduit during the insertion of the device into the reservoir, by the access hatch.

According to another advantageous characteristic of the present invention, the elastic stiffener is formed of an elastic thread.

According to another advantageous characteristic of the present invention, the well comprises main means of drawing at its base, associated with a reserve of liquid, and the flexible conduit defines secondary drawing means leading to said reserve.

According to another advantageous characteristic of the present invention, the secondary drawing means are controlled by the fuel return pipe coming from the engine.

According to another advantageous characteristic of the present invention, the secondary drawing means comprise a jet pump controlled by the fuel return pipe coming from the engine.

• la figure 1 représente une vue schématique en coupe verticale d'un dispositif de puisage conforme à la présente invention, selon le plan de coupe référencé I-I sur la figure 2,
• la figure 2 représente une vue de dessus d'un dispositif de puisage conforme à la présente invention,
• la figure 3 représente une seconde vue en coupe verticale du dispositif de puisage conforme à la présente invention, selon le plan de coupe référencé III-III sur la figure 2, lequel plan de coupe est orthogonal à celui de la figure 1, et
• la figure 4 illustre schématiquement la structure des moyens de puisage principaux utilisés dans le cadre de la présente invention.

Other characteristics, aims and advantages of the present invention will appear on reading the detailed description which follows, and with reference to the appended drawings given by way of nonlimiting example and in which:

• FIG. 1 represents a schematic view in vertical section of a drawing device in accordance with the present invention, according to the section plane referenced II in FIG. 2,
• FIG. 2 represents a top view of a drawing device according to the present invention,
• FIG. 3 represents a second view in vertical section of the drawing-off device according to the present invention, according to the section plane referenced III-III in FIG. 2, which section plane is orthogonal to that of FIG. 1, and
• Figure 4 schematically illustrates the structure of the main drawing means used in the context of the present invention.

In the appended figures, there is shown under the general reference 10, an exemplary embodiment of a motor vehicle fuel tank.

More specifically, in the appended figures, the upper wall of the tank is referenced 12, 14 the lower wall of the latter and 16 the side wall of said tank.

Of course, the representation given in the appended figures cannot be considered as limiting.

In practice, as mentioned above, today motor vehicle fuel tanks generally have complex and irregular shapes which are best suited to the space available on the motor vehicle.

The tanks 10 are generally made in the form of a plastic shell.

In addition, motor vehicle fuel tanks nowadays most often have the shape of a large horizontal surface and low height. More specifically, the fuel tanks are often extended horizontally in one direction.

In this context, it is desirable to provide two drawing points located respectively near of the ends of the reservoir, considered in the direction of horizontal elongation thereof. Thus, whatever the inclination and / or the acceleration of the vehicle, at least one of the two tapping points is located in the fuel, since the tank contains a minimum quantity of fuel.

As indicated above, according to the preferred embodiment of the present invention, the drawing device essentially comprises a vertical well 100 comprising main drawing means 200, and flexible conduits 300 provided with secondary drawing means 400 and associated with an elastic stiffener 500.

More specifically, in the context of the embodiment shown in the appended figures, the tank 10 comprises a single access hatch referenced 20, provided at one of the ends of the tank.

The vertical well 100 is fixed by any suitable leaktight means to this access door 20. These fixing means known to man will not be described in detail below.

However, it will be noted that the vertical well 100 essentially comprises a fixing plate 110 and means 120 for guiding the main drawing assembly 200.

The plate 110 is adapted to be fixed on the upper wall 12 of the tank 10 at the access hatch 20. Essentially, the plate 110 supports a suction pipe 112 through which the fuel from the drawing means 200 is directed towards the engine. The plate 110 also supports a return pipe 114 in which inversely is directed the fuel not used by the engine and returned to the tank.

The guide means 120 are adapted essentially to elastically stress the assembly main drawing 200 towards the bottom 14 of the tank 10. For this purpose, the guide means 120 can be adapted to guide the main drawing means 200 in vertical translation and urge these means 200 towards the bottom of the tank, as shown on the diagram Figure 1. Alternatively, the guide means 120 can support the main drawing assembly 200 pivoting about a horizontal axis, while urging these means 200 towards the bottom 14 of the tank as indicated above.

Such means of indexing a drawing assembly on the bottom of the tank, both by telescopic mounting and by pivoting mounting, are well known to those skilled in the art and will therefore not be described in detail by the after. It will be recalled that the purpose of these means is to maintain contact between the drawing point and the bottom 14 of the tank, whatever the deformations thereof, for example under the effect of aging, temperature variation, or else the weight of fuel contained in the tank 10.

The main drawing means 200 placed vertically on the access hatch 20 have the essential function of taking fuel from the tank 10 and directing it towards the suction pipe 112.

The main drawing means 200 can therefore be formed of any structure suitable for this purpose.

However, preferably, the main drawing means 200 are formed from a module marketed for a few years by the American company WALBRO. This module essentially comprises a pump 210 associated with a reserve bowl 250.

The general structure of this drawing module 200 has been shown diagrammatically in FIG. 4 appended.

We find in Figure 4 attached, a schematic representation of the reservoir 10 and a bowl of reserve 250 placed in it. The reserve bowl 250 is closed at its base, it can if necessary be opened at its upper end as shown diagrammatically in FIG. 4.

The pump 210 has its inlet 211 placed in the bowl 250 and its main outlet 212 connected to the suction pipe 112 carried by the plate 110. Thus, the pump 210 draws the fuel into the reserve bowl 250 and directs this fuel to the suction pipe 112, ie towards the motor. The pump 210 can be formed from any suitable known structure. It is preferably formed by a gear pump. Preferably a filter 123 is placed on the input 211.

Furthermore, as shown diagrammatically in FIG. 4, the module 200 preferably comprises a jet pump 220 for filling the reserve bowl 250, or at least maintaining a minimum level of fuel therein.

More precisely still, the jet pump 220 is supplied by a bypass line 214 taken from the outlet 212 of the pump 210, or at an intermediate pressure stage of this pump.

The jet pump 220 comprises a chamber 222 connected by a tube 224 passing through the lower wall of the bowl 250, at the bottom of the tank 10.

Preferably, the lower end of the tubing 222 is equipped with a filter 226. The chamber 222 also has a converging inlet 227 connected to the bypass pipe 214 coming from the pump 210 and an outlet 228 placed opposite the converge and which opens into the reserve bowl 250. In a manner known per se, the jet pump 220 works by the Venturi effect. The injection of fuel into the chamber 222 via the inlet 227, coming from the bypass line 214, causes a vacuum in the said chamber 222, which draws fuel into the reservoir 10 through the pipe 224 and directs it by outlet 228 in the reserve bowl 250.

To avoid emptying of the reserve bowl 250 through the tubing 224, into the reservoir 10, when the pump 210 stops, it is possible either to provide the tubing 224 with a non-return valve 225 as illustrated in FIG. 4 , or open the outlet 228 of the jet pump 220, in the reserve bowl 250 at a height greater than the minimum required level of fuel in the latter.

The drawing module 200 shown diagrammatically in FIG. 4 and previously described is preferably in accordance with the arrangements described and shown in document WO-88/01346.

The secondary drawing means 400 are provided at the second end of the tank, that is to say opposite to the main drawing means 200, as is clearly seen on examining FIG. 1.

The secondary drawing means 400 have the essential function of also supplying the reserve bowl 250. Thus, when due to an inclination or an acceleration of the vehicle the fuel is accumulated in the vicinity of the secondary drawing means 400, these make it possible to supply the reserve bowl 250 while the tubing 224 of the jet pump 220 can no longer open into the fuel, but into the air. In other words, the secondary drawing means 400 make it possible to avoid defusing the pump 210, even if the pipe 224 no longer dives into the fuel.

The secondary drawing means 400 can of course be formed of any structure suitable for this purpose.

Preferably, the secondary drawing means 400 are controlled by the fuel return pipe coming from the engine.

To this end, the secondary drawing means 400 preferably comprise a jet pump controlled by the aforementioned return duct.

In this context, two flexible pipes 310, 320 are provided, running close to the bottom 14 of the tank, between the base of the main drawing means 200 and the secondary drawing means 400.

A first flexible conduit 310 connects the return pipe 114 and the inlet of the jet pump 400. The second flexible conduit 320 connects the outlet of the jet pump 400 and the reserve bowl 250.

As seen in the examination of Figure 2, preferably, the two tubes 310, 320 extend substantially parallel to each other over their entire length.

More precisely still, preferably, within the framework of the present invention, the pipes 310, 320 do not extend directly in a straight line between the base of the main drawing means 200 and the secondary drawing means 400. On the contrary, the pipes 310, 320 have, near the main drawing means 200, a loop 302 which is connected to the base of the main drawing means 200 substantially perpendicular to the main elongation direction of the reservoir 10, which loop 302 extends to the 'opposite of the main drawing means 200 by a substantially straight strand 304, up to the secondary drawing means 400.

Jet pumps are well known to those skilled in the art. For this reason, the jet pump constituting the secondary drawing means 400 will not be described in detail below.

Note however that the jet pump 400 shown in the accompanying figures, in particular in Figure 1, comprises a housing 410 which rests on the bottom 14 of the tank 10 by feet 412. The housing 410 has an internal chamber 414. The chamber 414 communicates with the reservoir 10 through an opening 416 provided in the lower wall of the housing 410. Preferably, this opening 416 is equipped with a filter 418.

Furthermore, the inlet 420 of the chamber 414, preferably formed of a convergent is connected to the pipe 310. The outlet 422 of the chamber 414, preferably formed of a divergent, is connected on the other hand to the flexible pipe 320.

The second end of the flexible hose 320 opens into the bowl 250, as indicated above.

Here again, to avoid any emptying of the bowl 250 into the tank 10, through the opening 416 of the jet pump 400, in the event of the latter being stopped, it is possible either to provide a non-return valve. at this opening 416, or, as visible in FIG. 3, connect the end of the pipe 320, in the reserve bowl 250, to a vertical tube 252, the outlet of which is situated above the minimum required level of fuel in bowl 250.

Finally, and this is the essential characteristic of the invention, the flexible pipes 310, 320 are associated with an elastic stiffener 500.

The stiffener 500 is preferably formed from an elastic wire. The elastic wire 500 has the function of holding the pipes 310, 320 and above all the jet pump 400 forming secondary drawing means, against the bottom 14 of the tank 10. For this purpose, the two ends of the elastic wire 500 are connected respectively l one at the base of the main drawing means 200, the other on the housing 410 of the jet pump 400.

The elastic stiffening wire 500 is, however, suitable for not only firmly holding the jet pump 400 against the bottom 14 of the reservoir 10, but also allowing deformation of the flexible conduits 310, 320 during the insertion of the device, in the reservoir 10, through hatch 20.

For this purpose, preferably, the stiffening wire 500 is not straight but preferably comprises two main strands: a first strand 510 which extends essentially transversely to the direction of main horizontal elongation of the reservoir 10, adjacent to the main drawing means 200, and a second strand 220 substantially parallel to said main horizontal direction of elongation of the reservoir 10.

More specifically, the first strand 510 is preferably broken down into two elements 512, 514 each rectilinear and inclined between them. Likewise, the second strand 520 is broken down into different segments 521 to 526, each rectilinear, some vertical, others horizontal, adapted to surround and maintain the conduits 310, 320.

The above arrangement, namely the production of the stiffening wire 500 not in the form of a single rectilinear element, but in the essential form of two strands 510, 520 generally orthogonal makes it possible to facilitate the deformation and of the stiffener 500 and flexible pipes 310 , 320, on the one hand by twisting the first strand 510 of stiffener around its axis, on the other hand by bending the second strand 520 of the stiffener.

It will be noted on examining FIGS. 1 and 2 appended, that preferably the stiffening wire 500 is further provided, at its segments 514, 524 adjacent to the bottom 14 of the tank, with anti-noise pads 550, 552. De such anti-noise pads 550, 552 can be formed from any suitable material known to those skilled in the art.

Finally, it will be understood on examining FIGS. 2 and 3 that preferably the reserve bowl 250 and / or the well 100 supports a level gauging means 600. Preferably, this gauging means 600 comprises, in a manner known in itself, a level following crew comprising a lever 610 provided with a float 620, and pivoting around a horizontal axis 612, associated with a transducer comprising a resistive track associated with a cursor linked to the lever 610. Such a gauging means 600 well known to those skilled in the art will not be described in detail below. . It will simply be noted that FIG. 3 shows the two extreme detection positions of the float 620, at minimum level of fuel in the tank, and at maximum level of the latter.

Preferably, to avoid any interference between the lever 610 equipped with the float 620 and the flexible pipes 310, 320, or even the elastic stiffening wire 500, there is preferably provided a vertical intermediate plate between these elements.

Of course, the present invention is not limited to the particular embodiment which has just been described but extends to any variant in accordance with its claims.

Thus, for example, provision can be made not to rigidly fix the wire 500 on the base of the main drawing means 200, but to mount the wire 500 as well as the pipes 310, 320 to rotate about a vertical axis on the base. main drawing means 200. Furthermore, in this case, provision can be made to place the main drawing means 200 and the vertical well 100 not in the eccentric position at one end of the tank, but in the center of the latter. The secondary drawing means 400 are then free to move in rotation around the central well 100, as a function of the inclination and / or of the acceleration of the vehicle so that the secondary drawing means 400 are always placed in the fuel.

Furthermore, according to the embodiment described above, the jet pump 400 is supplied by the fuel return pipe coming from the engine. Alternatively however, this jet pump 400 can be supplied by a bypass taken at the outlet of pump 210 or at an intermediate pressure stage of this pump 210. For this, it suffices to connect the conduit 310 to this bypass. The fuel return pipe coming from the engine can then, if it exists, lead to the tank 10 or to the reserve 250.

Claims (15)

1. Device for pumping liquids in a tank, particularly for pumping fuel in a vehicle tank, comprising:

   - an access door (20) formed in a wall (12) of tank (10),

   - a well (100, 200), generally vertical, said well (100, 200) entering at least substantially to the bottom wall (14) of the tank (10),

   - at least one flexible pipe (310, 320), connected by a first end to the bottom of the well (100, 200), and which, at its second end, forms a pumping point remote from the bottom of the well (100, 200), characterized in that it comprises:

   - an elastic stiffener (500) associated with the flexible pipe (310, 320), to hold the pipe firmly in contact with the bottom wall (14) of the tank (10) at rest, while allowing the flexible pipe (310, 320) to be deformed when the device is inserted into the tank (10) through door (20), the well (100, 200) being fixed on the wall (12) of the tank (10) at the access door (20).
2. Device according to claim 1, characterized in that the elastic stiffener (500) is formed of an elastic thread.
3. Device according to claim 2, characterized in that the elastic thread (500) comprises essentially two strands: a first strand (510) which extends in a general direction perpendicular to the direction connecting the bottom of the vertical well (100, 200) to the second end of flexible pipe (310, 320) and a second strand (520) essentially parallel to the latter direction.
4. Device according to any of claims 2 or 3, characterized in that the elastic thread surrounds the flexible pipe (310, 320).
5. Device according to any of claims 2 to 4, characterized in that the elastic thread (500) is fitted with low-noise runners (550, 552).
6. Device according to any of claims 1 to 5, characterized in that the well (100, 200) comprises main pumping means (200) at its bottom provided with a reserve (250) and the flexible pipe (310, 320) defines a secondary pumping means (400) which opens into said reserve (250).
7. Device according to claim 6, characterized in that the main pumping means (200) comprise a pump (210), the inlet (211) of which dips into the reserve (250), and are fitted with a branch connection (214) at its outlet or at an intermediate pressure stage, to supply a jet pump (220) picking up fuel in the tank (14) to feed the reserve (250).
8. Device according to any of claims 1 to 7, characterized in that the flexible pipe (310, 320) is provided with secondary pumping means (420) controlled by the fuel return pipe (114) from the engine.
9. Device according to claim 8, characterized in that the secondary pumping means comprise a jet pump (400) controlled by the fuel return pipe (114) from the engine.
10. Device to claim 8, characterized in that the secondary pumping means comprise a jet pump (400) controlled by a branch connection taken from the outlet or at an intermediate pressure stage of a main pump (210).
11. Device according to any of claims 7 to 10, characterized in that the jet pump (220, 400) is provided with a non-return valve at its inlet opening.
12. Device according to any of claims 7 to 10, characterized in that the outlet pipe from the jet pump (220, 400) communicates with a tubing placed in the reserve (250) and which discharges into it at a height well above its bottom.
13. Device according to any of claims 1 to 12, characterized in that the well (100, 200) is provided with level gauge means (600).
14. Device according to any of claims 1 to 13, characterized in that the well (100) supports main pumping means (200) and urges these against the bottom (14) of the tank.
15. Device according to any of claims 1 to 14, characterized in that the elastic stiffener (500) and the associated flexible pipe (310, 320) are mounted in rotation about a vertical axis on the well (100).

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