Assembly including a fuel tank bladder

Abstract

1. An assembly including a bladder (3) for a fuel tank, the bladder (3) having a first configuration in which the bladder (3) is rolled onto itself such that a first geometric shape having a first volume is imparted to the bladder (3), and a second configuration in which the bladder (3) is unfolded such that a second geometric shape having a second volume is imparted to the bladder (3), the first volume being strictly less than the second volume, the assembly further including a fastening device configured to secure the assembly to an interior wall of the fuel tank (2).

Description

[Technical Field]

[0001] The present invention relates generally to controlling fuel vapor pressure in a fuel tank for a heat engine (also called an "internal combustion engine") vehicle, and more particularly to controlling fuel vapor pressure in a fuel storage system for an automobile. "Automobile" means any materiel mobile, especially a vehicle used on road, rail, sea, air, or space.

[0002] More particularly, the present invention relates to an assembly including a bladder for a fuel tank for a heat engine vehicle.

[0003] The invention also relates to an assembly according to the invention, which comprises a removable holding device.

[0004] The invention also relates to an assembly according to the invention, comprising an anti-sloshing device.

[0005] The invention also relates to a fuel storage system for a heat engine vehicle, comprising a fuel tank and at least one assembly according to the invention.

[0006] The invention also relates to the use of at least one assembly according to the invention in a fuel tank of a fuel storage system for a heat engine vehicle.

[0007] The invention also relates to a kit for manufacturing a fuel storage system for a heat engine vehicle, comprising an anti-sloshing device and at least one assembly according to the invention.

[0008] The invention also relates to a heat engine vehicle, in particular a motor vehicle, comprising a fuel storage system according to the invention. The invention has particular application to hybrid vehicles, which are vehicles equipped with a heat engine combined with one or more electric motors.

[0009] The invention also relates to a method for manufacturing a fuel storage system for a heat engine vehicle, comprising a fuel tank and at least one assembly according to the invention.

[0010] The invention also relates to a fuel storage system for a heat engine vehicle obtained by implementing the manufacturing method according to the invention.

[0011] The present invention further relates to a method for operating a fuel storage system according to the present invention.

[0012] The temperature of fuel stored in the fuel tank of a heat engine vehicle fuel storage system changes primarily depending on the outside air temperature. When the vehicle is outdoors, such as when driving or parked, the temperature of the fuel can fluctuate significantly depending on the weather the vehicle is exposed to. When the temperature of the fuel stored in the fuel tank rises, a certain amount of fuel evaporates. Because fuel tanks have a specified sealed volume, the generation of fuel vapor causes an increase in vapor pressure within the fuel tank. The increase in fuel vapor pressure places physical stress on the fuel tank wall, and if this pressure is not suppressed, it may lead to damage to the tank wall or even the risk of the fuel tank exploding. [Background technology]

[0013] For example, Patent Document 1 discloses a prior art in which an inflatable bladder is placed inside a fuel tank. This bladder is connected to an intake and exhaust pipe extending from the fuel tank, and allows air to be supplied to the bladder or a portion of the air stored in the bladder to be discharged alternately. In this way, the bladder expands or contracts in response to changes in the amount of fuel vapor in the fuel tank, changing the capacity for storing fuel vapor, thereby suppressing fluctuations in fuel vapor pressure.

[0014] While this bladder system certainly reduces the risk of fuel tank pressure buildup, it does present some problems. Indeed, due to their relatively bulky nature, bladders may not fit within the typically complex shape of fuel tanks, or the fuel tank may need to be reshaped to accommodate the bladder. For example, to achieve significant benefits in a 45-liter fuel tank, a bladder with an inflated volume of approximately 20 liters would be required, meaning that sufficient space within the fuel tank must be provided to accommodate the bladder. Furthermore, the bulk of the bladder complicates its insertion and installation into the fuel tank during manufacturing, which increases the cost and time required to manufacture the fuel tank. [Prior art documents] [Patent documents]

[0015] [Patent Document 1] International Publication No. 2021 / 013940 [Patent Document 2] International Publication No. 2010 / 029103 Summary of the Invention [Problem to be solved by the invention]

[0016] The present invention aims to solve, inter alia, the problems identified in the prior art by suppressing the pressure buildup of fuel vapor within the fuel tank and avoiding or reducing the disadvantages caused by the prior art bladder and its bulkiness. [Means for solving the problem]

[0017] To this end, the present invention provides an assembly according to a first embodiment including a bladder for a fuel tank, the bladder comprising: - a first configuration in which the bladder is rolled onto itself, preferably about an axis X, so as to impart a first geometric shape to the bladder having a first volume; a second configuration in which the bladder is deployed, preferably about an axis X, such that a second geometric shape having a second volume is imparted to the bladder; and the first volume is strictly less than the second volume, The present invention is directed to an assembly, wherein the assembly further includes a fastening device configured to fasten the assembly to an interior wall of the fuel tank.

[0018] Thus, the bulky bladder of the prior art is replaced with a bladder that reduces its volume when inserted and secured into the fuel tank. This allows the bladder to be easily inserted into the fuel tank through an opening in the fuel tank wall, such as an inlet port in the fuel tank. Furthermore, by using the securing device, the bladder does not deploy anywhere within the fuel tank, but rather deploys within a predetermined space in the tank, eliminating the need to modify the shape of the fuel tank to accommodate the bladder in this space. This predetermined space is selected to allow the bladder to deploy smoothly within the fuel tank and to avoid interference with the interior of the fuel tank that could lead to damage to the bladder in the second configuration. The inlet port is for inserting one or more internal fuel tank components into the fuel tank, such as a fuel pump that is installed at the bottom of the fuel tank. After the internal fuel tank components are installed and before the fuel tank is put into service, the inlet port is sealed. In one example, the diameter of the inlet port is 130 mm.

[0019] Advantageously, the bladder is manufactured in an unfolded state, which is its initial shape. Even more advantageously, the bladder is manufactured using an elastic material, i.e., a flexible and deformable material that returns to its initial shape when released from physical stress. A bladder manufactured in this manner is "rollable." The "rollable" characteristic of a bladder refers to the bladder's ability to transition from an unfolded configuration to a rolled configuration (and vice versa) without undergoing significant plastic deformation, similar to a rollable mattress. In one example, the bladder is manufactured from a thermoplastic elastomer material, such as thermoplastic polyurethane (TPU). This characteristic allows the bladder to deform not only when unfolded, but also when rolled onto itself, e.g., in the first configuration, and also allows the bladder to twist and / or flex.

[0020] Alternatively, the bladder is made of polyethylene (PE), polyamide (PA), or in the form of a multi-layer material comprising polyethylene (PE), preferably high density polyethylene (HDPE), and ethylene vinyl alcohol (EVOH).

[0021] Preferably, the polyethylene is high density polyethylene (HDPE) and the polyamide is polyamide 6, 11 or 12 (PA6, PA11 or PA12).

[0022] Advantageously, the multi-layer comprises a polyethylene (PE) layer, preferably a high density polyethylene (HDPE) layer, and an adhesive layer provided between the ethylene vinyl alcohol (EVOH) layer.

[0023] Thus, various materials can be selected to implement the bladder to impart desired characteristics to the bladder, such as low cost, physical durability, flexibility, deformability, or fuel impermeability.

[0024] Furthermore, by having the bladder rolled upon itself in the first configuration, the bladder can be inserted into the fuel tank after, not necessarily during, the fuel tank's manufacture, thereby simplifying the fuel tank production line.

[0025] Preferably, the first geometric shape is a generally cylindrical shape.

[0026] Preferably, the second geometric shape is generally prismatic, cylindrical or spherical.

[0027] The second volume is proportional to the volume of fuel in the fuel tank. Advantageously, the second volume is 20% to 50% of the volume of fuel in which the bladder is immersed, and preferably, the second volume is 20% to 30% of the volume of fuel in which the bladder is immersed.

[0028] In this way, the size of the bladder can be easily determined according to the specifications that the fuel tank must comply with. In other words, the shape and capacity of the bladder can be easily adapted to suit the structure of the fuel tank, which demonstrates the flexibility of use of the present invention.

[0029] "Fuel" means a hydrocarbon suitable for supplying a heat engine. Specialized engine fuels include those based on alcohols, such as ethanol, bioethanol, butanol, methanol, etc., as well as mixtures of these with, for example, hydrocarbons.

[0030] "Tank" means a sealed container capable of storing fuel under a wide variety of changing conditions of use and ambient conditions. The tank according to the present invention includes a wall, also called an envelope, that defines a hollow body. The tank walls include an inner wall and an outer wall. The inner wall faces the interior space of the hollow body, and the outer wall faces the exterior space of the hollow body. The hollow body according to the present invention is made of metal or a plastic material, preferably a plastic material. When made of a plastic material, the body contains at least one synthetic resin polymer that is solid at room temperature. A hollow body made of a plastic material is preferred because it has good elasticity and can be easily molded into complex shapes.

[0031] The hollow body made of plastic material can be realized by any known processing method, one known embodiment being injection molding, although extrusion blow molding and rotational molding are also known.

[0032] "Plastic material" refers to both a single-layered, generally homogeneous material and a multi-layered, heterogeneous material.

[0033] The hollow body advantageously comprises at least one thermoplastic polymer, ie a polymer that melts or softens under the influence of heat and becomes mouldable.

[0034] "Polymer" refers to both homopolymers and copolymers (especially binary or ternary). Non-limiting examples of such copolymers include random copolymers, sequenced copolymers, graft copolymers, etc.

[0035] Any type of thermoplastic polymer or copolymer having a melting point below its decomposition temperature is suitable. Thermoplastic polymers with a melting point spread of ten degrees Celsius (10°C) or more are particularly suitable. Examples of this type of material include materials with polydispersity in molecular weight.

[0036] Polyolefins, thermoplastic polyesters, polyketones, polyamides, and copolymers thereof, among others, can be used. Mixtures of polymers or copolymers can also be used, as can mixtures of polymeric materials with inorganic, organic, and / or natural fillers, such as, but not limited to, carbon, salts, other inorganic derivatives, natural or polymeric fibers. Multi-layer structures consisting of interlinked laminates containing at least one of the above polymers or copolymers can also be used.

[0037] A commonly used polymer is polyethylene, with good results being achieved with high density polyethylene (HDPE).

[0038] In one example, the hollow body comprises a multi-layer structure including at least one layer of thermoplastic material and at least one additional layer advantageously composed of a barrier material against liquids and / or gases. Preferably, the type and thickness of the barrier layer are selected to maximize the inhibition of permeability of liquids and gases in contact with the tank wall. Preferably, this layer is based on a barrier material, i.e., a fuel-impermeable resin, such as EVOH (partially hydrolyzed ethylene vinyl acetate copolymer). Alternatively, the hollow body can be surface-treated (fluorinated or sulfonated) to make it fuel-impermeable.

[0039] Advantageously, on local coordinates XYZ associated with the bladder, in a first configuration the bladder is rolled about axis X, and in a second configuration the bladder is expanded about axis X, and the bladder is configured to have a third configuration in which it is compressed along axis Y and / or axis Z such that a third geometric shape having a third volume is imparted to the bladder, the third volume being greater than or equal to the first volume and strictly less than the second volume.

[0040] Thus, when the bladder is in operation within the fuel tank, the second configuration is a rest configuration of the bladder and the third configuration is a working configuration of the bladder. In the working configuration of the bladder, the bladder deforms under the influence of pressure within the fuel tank. Preferably, the deformation of the bladder is compression of the bladder along axis Y and / or axis Z. Additionally, the deformation of the bladder can also be compression of the bladder along axis X.

[0041] The present invention also contemplates an assembly according to the first embodiment, further comprising a removable retaining device for the bladder in the first configuration.

[0042] The removable retaining device may be, for example, an elastic band, a tie cord, a U-clip, or the like.

[0043] This effectively holds the bladder in the first configuration and allows for easy release of the bladder.

[0044] The present invention also contemplates an assembly according to the first embodiment, characterized in that the fixing device comprises a member selected from the group consisting of members configured to fix the assembly to the inner wall of the fuel tank, such as clipping members, ratcheting members, fitting members, adhesive members, clamping members, clamping members and welding members.

[0045] According to the present invention, an assembly according to the first embodiment is also envisaged, characterized in that it further comprises an anti-sloshing device.

[0046] Anti-slosh devices are used to reduce noise associated with sloshing in the fuel tank when a vehicle accelerates, brakes, or turns. These devices are also called "anti-slosh baffles" or "baffles."

[0047] In one embodiment, the anti-sloshing device is realized in a plastic material, for example polyoxymethylene (POM).

[0048] Advantageously, the anti-sloshing device supports the fixing device.

[0049] Further advantageously, the anti-sloshing device comprises a handle for allowing the anti-sloshing device to be operated inside the fuel tank, in particular for fixing the anti-sloshing device in the fuel tank, for example at the bottom of the fuel tank, for which purpose an engagement part of the fixing device is adapted to be arranged in the fuel tank, for example at the bottom of the fuel tank.

[0050] Preferably, the fixing device is manufactured integrally with the anti-sloshing device, and more preferably, the engaging portion of the fixing device is welded to the bottom of the fuel tank.

[0051] Alternatively, the anti-sloshing device comprises a spring device. In this case, the anti-sloshing device consists of two parts, one of which moves relative to the other and which are connected by a spring device. The spring device is compressed, reducing the size of the anti-sloshing device and facilitating its insertion into the fuel tank. The anti-sloshing device is placed in a predetermined position in the fuel tank, for example, against the bottom of the fuel tank. The spring device is then decompressed to press one movable part of the anti-sloshing device against the bottom wall of the fuel tank and the other movable part against the wall opposite the bottom wall of the tank. In this final position, the anti-sloshing device is fixed between the bottom wall of the fuel tank and the wall opposite the bottom wall of the fuel tank. This type of anti-sloshing device, also known as a "spring-loaded baffle" in English, is also described in Patent Document 2.

[0052] According to the present invention, there is provided an assembly according to a second embodiment including a bladder for a fuel tank, the bladder comprising: - a first configuration in which the bladder is compressed to impart a first geometric shape having a first volume to the bladder; - a second configuration in which the bladder is decompressed such that a second geometric shape having a second volume is imparted to the bladder; and the first volume is strictly less than the second volume, Also envisaged is an assembly wherein the assembly further comprises an anti-sloshing device.

[0053] The anti-sloshing device not only enables the assembly to reduce the pressure buildup of fuel vapor within the fuel tank, but also reduces noise associated with sloshing within the fuel tank.

[0054] According to the present invention, an assembly according to the second embodiment is also envisaged, characterized in that it further comprises a fixing device configured to fix the assembly to an inner wall of the fuel tank.

[0055] The retention device allows the bladder to deploy within a predetermined space in the fuel tank, rather than deploying anywhere within the tank, selected to allow the bladder to deploy smoothly within the fuel tank and to avoid interference with the interior of the fuel tank that could result in damage to the bladder in the second configuration.

[0056] The present invention also contemplates an assembly according to the second embodiment, characterized in that the fixing device comprises a member selected from the group consisting of members configured to fix the assembly to the inner wall of the fuel tank, such as clipping members, ratcheting members, fitting members, adhesive members, clamping members, clamping members and welding members.

[0057] The present invention also contemplates an assembly according to the second embodiment, wherein the bladder is configured to have a third configuration when compressed such that a third geometric shape having a third volume is imparted to the bladder, the third volume being greater than or equal to the first volume and strictly less than the second volume.

[0058] Thus, when the bladder is in operation within the fuel tank, the second configuration is a rest configuration of the bladder and the third configuration is a working configuration of the bladder, in which the bladder deforms under the influence of pressure within the fuel tank.

[0059] According to the present invention, - a fuel tank; - at least one assembly extending into the fuel tank and conforming to the above assembly; A fuel storage system for a heat engine vehicle, comprising: Fuel storage systems configured to store fuel outside of a bladder within the fuel tank are also contemplated.

[0060] According to the present invention, the at least one assembly extends into the fuel tank whether the bladder is in the first, second or third configuration.

[0061] In the case of a fuel storage system including at least one assembly according to the first embodiment, the fuel storage system is characterized in that in the second configuration of the bladder, the bladder is deployed within the fuel tank, preferably about axis X.

[0062] Thus, the prior art fuel storage system for a heat engine vehicle is replaced here by a fuel storage system for a heat engine vehicle including at least one assembly including a bladder that reduces in volume when inserted and secured in the fuel tank. The insertion of the bladder into the fuel tank is performed through an opening in the wall of the fuel tank, which opening is sealed before the fuel storage system is put into service. In one example, the opening is an insertion port of the fuel tank. The assembly can combine the bladder with a removable retention device and / or anti-sloshing device for the bladder in the first configuration, and the at least one assembly reduces in volume when inserted and secured in the fuel tank. The insertion of the at least one assembly into the fuel tank is performed through an opening in the wall of the fuel tank, which opening is sealed before the fuel storage system is put into service. In one example, the opening is an insertion port of the fuel tank.

[0063] A "fuel storage system for a heat engine vehicle," also referred to as a "fuel system," means any device incorporated into a heat engine vehicle whose function is to store, purify, meter, or transport fuel for delivery to the heat engine. The fuel system includes at least one fuel tank and fuel supply piping to the heat engine. The fuel system may also include one or more accessories, including, but not limited to, a fuel tank intake valve and piping, a fill pipe, a canister, a fuel filter, a fuel pump, a fuel tank gauge, electrical connectors, sealing plugs, and generally any component through which liquid or gaseous fuel passes, such as a fuel vapor recirculation line.

[0064] The fuel storage system according to the present invention further includes a vent pipe connecting the interior of the bladder to the exterior of the fuel tank. If the bladder material is impermeable to fuel and fuel vapor, the connection to the exterior of the fuel tank is open to the atmosphere, allowing the fuel storage system to alternately supply air to the bladder or vent a portion of the air contained in the bladder. If the bladder material is permeable to fuel and / or fuel vapor, the connection to the exterior of the fuel tank is open to a fuel vapor circulation pipe leading to the canister, allowing the fuel storage system to alternately supply gas to the bladder or vent a portion of the gas contained in the bladder to the canister. The gas supplied to the bladder can be air coming directly from the atmosphere or air that has passed through the canister.

[0065] Preferably, in the second configuration, the bladder is fully immersed in fuel when the fuel tank is full of fuel.

[0066] Advantageously, the fuel storage system further comprises at least one heat storage member extending into the fuel tank, the heat storage member comprising a phase change material having a melting point between 18°C ​​and 40°C, the phase change material being preferably calcium chloride hexahydrate (CaCl2.6H2O), octadecane (C 18 H 38 ), cyclohexanol (CH 12 O), and glycerin derivatives.

[0067] The at least one heat storage element absorbs heat, particularly when the fuel reaches a temperature close to the melting point of the phase change material. Indeed, the melting reaction is endothermic, consuming the heat of the fuel. The at least one heat storage element thus reduces the temperature rise of the fuel, and thus the generation of fuel vapor in the fuel tank. This reduction in the generation of fuel vapor allows the volume of the bladder to be reduced, thereby reducing the disadvantages associated with the bladder volume, particularly the limited effective tank volume. It can thus be seen that the synergistic effect of the at least one heat storage element and the bladder exceeds the effects achieved by the at least one heat storage element and the bladder separately.

[0068] Advantageously, in the third configuration of the bladder, the bladder of the fuel storage system including the assembly according to the first embodiment is compressed along axis Y and / or axis Z within the fuel tank.

[0069] This reduces pressure buildup within the fuel tank as fuel vapor occupies the new volume within the fuel tank, which volume is provided by the bladder in the third bladder configuration.

[0070] Furthermore, compressing the bladder along axis Y and / or axis Z within the fuel tank can more effectively reduce the volume of the bladder. In fact, when the bladder has its maximum length along axis X, compressing the bladder walls along axis Y and / or axis Z is easier than compressing the bladder along axis X.

[0071] The invention also envisages the use of at least one assembly according to the above-described assembly in a fuel tank, the bladder being intended to limit the pressure buildup in the fuel tank and thus the physical stresses on the fuel tank.

[0072] According to the present invention, a manufacturing kit for a fuel storage system for a thermal engine vehicle is also envisaged, the system comprising a fuel tank and at least one anti-sloshing device extending inside the fuel tank, the kit being characterized in that it comprises at least one assembly conforming to the above-mentioned assembly, the bladder being supported by the at least one anti-sloshing device.

[0073] In this way, a fuel tank equipped with at least one anti-sloshing device can be easily fabricated into a fuel tank equipped with at least one anti-sloshing device supporting a bladder of an assembly according to the invention.

[0074] The present invention also contemplates a heat engine vehicle including a fuel storage system in accordance with any of the above systems.

[0075] A method for manufacturing a fuel storage system (1) for a thermal engine vehicle, comprising the following steps: a) manufacturing a fuel tank; b) manufacturing a bladder conforming to the bladder; c) maintaining the bladder in a first configuration; d) inserting the bladder into the fuel tank through an opening in the wall of the fuel tank; e) securing the bladder within the fuel tank such that the bladder extends within the fuel tank; f) releasing the bladder to transition from the first configuration to the second configuration, such that in the second configuration the bladder deploys within the fuel tank, preferably about axis X; Also contemplated is a method of manufacturing a fuel storage system for a heat engine vehicle, including:

[0076] In one example, step d) of inserting the bladder into the fuel tank through an opening in the wall of the fuel tank is performed manually by an operator.

[0077] In a preferred embodiment, the expanded shape of the bladder is the initial shape of the bladder, i.e., the shape of the bladder as it is manufactured. Furthermore, if the bladder is manufactured from an elastic material, its deformation, e.g., due to the bladder rolling on itself, is reversible. In this case, the transition from the first configuration to the second configuration is automatic. Indeed, after releasing the bladder in step f), i.e., after removing the physical stress that kept the bladder rolled on itself, the bladder will expand by itself and return completely or almost completely to its initial shape. If the bladder almost completely returns to its initial shape, a pressurized gas, e.g., pressurized air, can be introduced into the bladder to assist it in returning completely to its initial shape.

[0078] Advantageously, in the above method, step e) of fixing the bladder within the fuel tank is performed by clipping, ratcheting, fitting, gluing, clamping, clamping or welding the bladder to the inner wall of the fuel tank.

[0079] Preferably, the inner wall of the fuel tank is the bottom wall of the fuel tank.

[0080] Advantageously, in the method, step c) of holding the bladder in the first configuration is performed by a removable holding device.

[0081] According to the invention, a method for manufacturing a fuel storage system for a heat engine vehicle is provided, comprising the following steps: a) manufacturing a fuel tank; b) manufacturing at least one assembly conforming to any of the above assemblies; c) maintaining the bladder in a first configuration; d) inserting at least one assembly into the fuel tank through an opening in a wall of the fuel tank; e) securing at least one assembly within the fuel tank such that the at least one assembly extends within the fuel tank; f) releasing the bladder to transition from the first configuration to the second configuration within the fuel tank; Also contemplated is a method of manufacturing a fuel storage system for a heat engine vehicle, including:

[0082] In one example, step d) of inserting the at least one assembly into the fuel tank through an opening in the wall of the fuel tank is performed manually by an operator.

[0083] In the case of a fuel storage system including at least one assembly according to the first embodiment, a step f) of releasing the bladder is performed to transition from the first configuration to the second configuration, so that in the second configuration the bladder deploys within the fuel tank, preferably about the axis X.

[0084] In a preferred embodiment, the expanded shape of the bladder is the initial shape of the bladder, i.e., the shape of the bladder as it is manufactured. Furthermore, if the bladder is manufactured from an elastic material, its deformation, e.g., due to the bladder rolling on itself, is reversible. In this case, the transition from the first configuration to the second configuration is automatic. Indeed, after releasing the bladder in step f), i.e., after removing the physical stress that kept the bladder rolled on itself, the bladder will expand by itself and return completely or almost completely to its initial shape. If the bladder almost completely returns to its initial shape, a pressurized gas, e.g., pressurized air, can be introduced into the bladder to assist it in returning completely to its initial shape.

[0085] Advantageously, in the above method, step e) of fixing the at least one assembly in the fuel tank is performed by clipping, ratcheting, fitting, gluing, clamping, clamping or welding the at least one assembly to the inner wall of the fuel tank.

[0086] Preferably, the inner wall of the fuel tank is the bottom wall of the fuel tank.

[0087] Preferably, when the at least one assembly is fastened to the bottom wall of the fuel tank, the fastening is performed by the above-mentioned spring device, so that the at least one assembly is fastened between the bottom wall of the fuel tank and a wall opposite to the bottom wall of the fuel tank.

[0088] Advantageously, in the method, step c) of holding the bladder in the first configuration is performed by a removable holding device.

[0089] The invention also provides a fuel storage system for a heat engine vehicle, characterized in that it is obtained by implementing the manufacturing method described above.

[0090] Finally, the present invention also contemplates a method of operating a fuel storage system in accordance with any of the above systems, characterized in that it includes a step of deforming the bladder from the second configuration to the third configuration in response to an increase in pressure within the fuel tank.

[0091] The step of deforming the bladder from the second configuration to the third configuration is effected solely by an increase in pressure within the fuel tank.

[0092] Other characteristics and advantages of the invention will become apparent from the following description, given by way of non-limiting reference, with reference to the accompanying drawings, in which: [Brief explanation of the drawings]

[0093] [Figure 1] FIG. 2 is an exploded perspective view of the major components of a fuel storage system according to the present invention, showing the bladder in a second configuration. [Figure 2] FIG. 2 is a view similar to FIG. 1 showing the bladder in a first configuration. [Figure 3] FIG. 3 is a view similar to FIG. 2 showing the bladder beginning to connect with the fuel tank. [Figure 4] 4A-4C are cross-sectional views along plane T of the fuel tank of FIG. 3 showing different graduated positions of the bladder coupled to the fuel tank. [Figure 5] 4A-4C are cross-sectional views along plane T of the fuel tank of FIG. 3 showing different graduated positions of the bladder coupled to the fuel tank. [Figure 6] 4A-4C are cross-sectional views along plane T of the fuel tank of FIG. 3 showing different graduated positions of the bladder coupled to the fuel tank. [Figure 7] 4A-4C are cross-sectional views along plane T of the fuel tank of FIG. 3 showing different graduated positions of the bladder coupled to the fuel tank. [Figure 8] 4A-4C are cross-sectional views along plane T of the fuel tank of FIG. 3 showing different graduated positions of the bladder coupled to the fuel tank. [Figure 9] 4A-4C are cross-sectional views along plane T of the fuel tank of FIG. 3 showing different graduated positions of the bladder coupled to the fuel tank. [Figure 10]4A-4C are cross-sectional views along plane T of the fuel tank of FIG. 3 showing different graduated positions of the bladder coupled to the fuel tank. [Figure 11] 4A-4C are cross-sectional views along plane T of the fuel tank of FIG. 3 showing different graduated positions of the bladder coupled to the fuel tank. [Figure 12] 4A-4C are cross-sectional views along plane T of the fuel tank of FIG. 3 showing different graduated positions of the bladder coupled to the fuel tank. [Figure 13] 4A-4C are cross-sectional views along plane T of the fuel tank of FIG. 3 showing different graduated positions of the bladder coupled to the fuel tank. [Figure 14] 1 is a perspective view of a heat engine vehicle according to the present invention; DETAILED DESCRIPTION OF THE INVENTION

[0094] Identical or similar elements in each drawing will be given the same reference numerals, possibly with the addition of suffixes, so that the description of their structure and function will not be repeated mechanically.

[0095] In the following description, directions are those of the drawings. In particular, the terms "upper", "lower", "left", "right", "upper", "lower", "front" and "rear" are generally understood as directions shown in the drawings.

[0096] 1 and 2 show the main components of a fuel storage system 1 according to the present invention.

[0097] Of the main components of the fuel storage system 1, a fuel tank 2 and a bladder 3 are shown.

[0098] The fuel tank 2, which is usually made of a plastic material, is configured to store fuel outside a bladder 3 within the fuel tank 2, which the heat engine vehicle uses, inter alia, for its propulsion. The fuel tank 2 includes a wall defining a hollow body defining an internal volume in which liquid and gaseous fuel are stored, in proportions that depend, inter alia, on the pressure and temperature conditions inside the fuel tank 2. A fuel tank typically includes a fill pipe for filling the tank with fuel, a vent pipe for venting fuel evaporative gases under certain conditions, and an injection pipe for delivering fuel to the heat engine vehicle engine. These three pipes are well known in the prior art and are therefore not shown in the drawings or described further below.

[0099] The bladder 3 includes an elastically deformable wall that allows it to unfold and roll without plastic deformation. Here, the bladder is manufactured in the unfolded state using an elastic material, i.e., a flexible and deformable material that returns to its original shape when released from physical stress, which is its initial shape. In one example, the bladder is manufactured using a thermoplastic elastomer material, such as thermoplastic polyurethane (TPU).

[0100] In another example, the bladder is made of polyethylene (PE), polyamide (PA), or a multi-layered structure containing polyethylene (PE) and ethylene vinyl alcohol (EVOH). Preferably, the polyethylene is high-density polyethylene (HDPE), the polyamide is polyamide 6, 11, or 12 (PA6, PA11, or PA12), and the multi-layered structure includes an adhesive layer between the high-density polyethylene layer and the ethylene vinyl alcohol layer. Advantageously, the multi-layered structure includes an adhesive layer between the polyethylene (PE) layer, preferably the high-density polyethylene (HDPE) layer, and the ethylene vinyl alcohol (EVOH) layer.

[0101] In accordance with the present invention, the bladder 3 is configured to have a first configuration and a second configuration. In the first configuration, the bladder 3 is rolled onto itself about axis X (see FIG. 2) such that a first geometric shape having a first volume is imparted to the bladder 3. In the illustrated example, the first geometric shape is generally cylindrical. In the second configuration, the bladder 3 unfolds about axis X (see FIG. 1) such that a second geometric shape having a second volume is imparted to the bladder 3. In the illustrated example, the second geometric shape is generally prismatic. Alternatively, the second geometric shape is generally cylindrical or spherical (not shown). In either case, the first volume is strictly less than the second volume.

[0102] In practice, the second volume is proportional to the volume of fuel in the fuel tank 2. Advantageously, the second volume is 20% to 50% of the volume of fuel in which the bladder 3 is immersed, and preferably, the second volume is 20% to 30% of the volume of fuel in which the bladder 3 is immersed.

[0103] The maximum capacity of the bladder 3 is selected depending on the volume and shape of the fuel tank 2, and the suggested range of values ​​can be adapted to some types of automotive tanks.

[0104] Axis X is part of a local coordinate system XYZ associated with bladder 3. Bladder 3 is configured to have a third configuration. In the third configuration, bladder 3 is compressed along axis Y and / or axis Z such that a third geometric shape (not shown) having a third volume is imparted to the bladder. The third volume is greater than or equal to the first volume and strictly less than the second volume.

[0105] 1 and 2, the bladder 3 is not yet connected to the fuel tank 2.

[0106] 3 shows the point at which the bladder 3 begins to be inserted into the fuel tank 2 from the opening 6, that is, the point at which the bladder begins to be connected to the fuel tank 2. The opening 6 is an insertion port for the fuel tank.

[0107] 4 to 13 show the different stages of positioning of the bladder 3 in the fuel tank 2 up to the final position, ie the position where the connection of the bladder 3 with the fuel tank 2 is complete.

[0108] 11 and 12, the bladder 3 is part of an assembly that further includes a fixing device configured to fix the assembly to the inner wall of the fuel tank 2. The fixing device includes a member selected from the group consisting of members configured to fix the assembly to the inner wall of the fuel tank 2, such as clipping members, ratcheting members, fitting members, adhesive members, clamping members, clamping members, and welding members. The assembly also includes a removable retention device 4, here a tie string, for the bladder 3 in the first configuration, and an anti-sloshing device 5 that supports the bladder 3. In one example, the anti-sloshing device 5 is realized in a plastic material, for example polyoxymethylene (POM).

[0109] As an alternative to a tie string, the removable retaining device 4 may be an elastic string or a clip, such as a U-clip (not shown).

[0110] 1 to 13 also show steps in a method for manufacturing a fuel storage system 1 for a heat engine vehicle including the above assembly. The method includes the following steps: a) manufacturing a fuel tank 2 (FIG. 1 shows the fuel tank 2 thus manufactured); b) manufacturing the assembly (FIG. 1 shows the assembly thus manufactured); c) holding the bladder 3 in a first configuration (FIG. 2 shows the above assembly with the bladder 3 held in the first configuration); d) inserting the assembly into the fuel tank 2 (FIGS. 3 to 11 show the steps of inserting the assembly, inside which the bladder 3 is held in the first configuration, into the fuel tank 2). The insertion of the assembly is carried out through an opening 6 in the wall 7 of the fuel tank 2 (see FIG. 11); e) fixing the assembly in the fuel tank 2 so that it extends into the fuel tank 2 (Figure 12 shows the assembly in a fixed position); f) releasing the bladder 3 to transition from the first configuration to the second configuration, such that in the second configuration the bladder 3 deploys about the axis X within the fuel tank 2 (FIG. 13 shows the bladder deployed about the axis X within the fuel tank 2).

[0111] 3 to 10, it can be seen that there is material interference between the assembly and the opening 6, but this interference is due to the fact that the bending deformation of the assembly is not shown in these drawings. In reality, in the illustrated fuel tank 2, the assembly must bend in order to pass through the opening 6.

[0112] Step c) of holding the bladder 3 in the first configuration is performed by a removable holding device 4, here a tie string.

[0113] Step e) of fixing the assembly in the fuel tank 2 is carried out by a fixing device of the assembly to the inner wall of the fuel tank 2, which here comprises a clipping member 8 (FIG. 11 shows the assembly before clipping, and FIG. 12 shows the assembly after clipping).

[0114] In the illustrated example, the clip fastening member 8 is a female part of a clip. The female part of the clip is supported by the anti-sloshing device 5, which further comprises a handle 9 for facilitating the manipulation of the anti-sloshing device 5 inside the fuel tank 2, in particular for securing the anti-sloshing device 5 to the bottom of the fuel tank 2 by clipping. For this purpose, a male part of the clip is arranged on the bottom of the fuel tank 2. Preferably, the female part of the clip is manufactured integrally with the anti-sloshing device 5, and the male part of the clip is welded to the bottom of the fuel tank 2.

[0115] As an alternative to a fixing device including a clip fastening member 8, fixing of the assembly within the fuel tank 2 may be achieved by a fixing device including ratcheting, fitting, adhesive, clamping, clamping or welding of the assembly to the inner wall of the fuel tank 2 (means not shown).

[0116] Step f) of releasing the bladder 3 here consists of untying the string.

[0117] 13 shows a fuel storage system 1 for a heat engine vehicle obtained by carrying out the manufacturing method described above, which system includes a fuel tank 2 and the above-described assembly. The above-described assembly extends into the fuel tank 2. In a second configuration, the bladder 3 expands about an axis X within the fuel tank 2. In a third configuration, the bladder 3 is compressed along an axis Y and / or an axis Z within the fuel tank 2 (this configuration is not shown).

[0118] When the bladder 3 is used in the fuel tank 2 of the fuel storage system 1 for a heat engine vehicle, the pressure increase in the fuel tank 2 can be suppressed.

[0119] In fact, when the temperature of the fuel stored in the fuel tank 2 rises, for example when the outside air temperature exceeds the temperature of the fuel, part of the fuel evaporates and fuel vapor is generated inside the fuel tank 2. Because the fuel tank 2 has a defined sealed volume, an increase in the amount of fuel vapor causes an increase in gas phase pressure inside the fuel tank 2. Hereinafter, we will explain how the fuel storage system 1 according to the present invention suppresses this pressure increase.

[0120] The bladder 3 is compressed by the pressure of the vapor phase within the fuel tank 2. Because the walls of the bladder 3 are deformable, the stress on the walls of the bladder 3 is balanced, and this balance allows all or part of the air contained within the bladder 3 to be discharged through the vent pipe 10. One end of the vent pipe 10 is connected to the bladder 3, more specifically, to the internal volume of the bladder 3, via a first fitting of the vent pipe 10, and the other end is connected to the outside of the fuel tank 2 via a second fitting 11 of the vent pipe 10. Thus, the volume of the bladder 3 extending into the fuel tank 2 decreases, and the volume occupied by the fuel vapor increases, resulting in a decrease in the pressure of the fuel vapor. For example, if the outside air temperature falls below the temperature of the fuel, some of the fuel vapor condenses. This reduces the amount of fuel vapor in the fuel tank 2 and also reduces its pressure. The stress on the walls of the bladder 3 is balanced again, and this balance allows the bladder 3 to fill through the vent pipe 10, increasing the volume of the bladder 3 extending into the fuel tank 2. Although the vent pipe 10 is not shown in all drawings, the vent pipe is connected to the bladder 3 prior to insertion of the bladder 3 into the fuel tank 2. The vent pipe 10 is made of a flexible material so that it can deform with the bladder 3 as it is inserted into the fuel tank 2.

[0121] Thus, when operating within the fuel tank 2, the bladder 3 deforms in response to an increase in pressure within the fuel tank 2, causing the bladder 3 to transition from the second configuration to the third configuration, the deformation being part of the method of operation of the fuel storage system 1.

[0122] In an alternative embodiment (not shown), the above assembly is replaced by a single bladder 3. In another alternative embodiment (not shown), the bladder 3 is coupled with one or both of a removable retaining device 4 and an anti-sloshing device 5.

[0123] 1 to 13 show a kit for manufacturing a fuel storage system 1 for a heat engine vehicle. The fuel storage system 1 for a heat engine vehicle includes a fuel tank 2 and an anti-sloshing device 5 extending into the fuel tank 2. The kit includes the above assembly, with the bladder 3 supported by the anti-sloshing device 5.

[0124] FIG. 14 shows a heat engine vehicle 20 including the fuel storage system 1 described above. [Explanation of symbols]

[0125] 1. Fuel storage system 2 fuel tanks 3. Vlada 4. Removable holding device 5 Anti-sloshing device 6 Opening 7. Wall 8 Clip fastening 9 Handle 10 Ventilation pipe 11 Ventilation pipe fittings 20 vehicles

Claims

1. An assembly including a bladder (3) for a fuel tank, said bladder (3) comprising: a first configuration in which the bladder (3) is rolled onto itself so as to impart a first geometric shape having a first volume to the bladder (3); a second configuration in which the bladder (3) is deployed so as to impart a second geometric shape having a second volume to the bladder (3); configured to have the first volume is strictly less than the second volume; Assembly, characterized in that said assembly further comprises a fixing device configured to fix said assembly to an inner wall of said fuel tank (2).

2. 2. The assembly of claim 1, wherein, on local coordinates XYZ associated with the bladder (3), in the first configuration the bladder (3) is rolled around axis X, in the second configuration the bladder (3) is expanded around axis X, and the bladder (3) has a third configuration compressed along axis Y and / or axis Z such that a third geometric shape having a third volume is imparted to the bladder (3), the third volume being greater than or equal to the first volume and strictly less than the second volume.

3. 3. The assembly according to claim 1 or 2, characterized in that the fixing device comprises a member selected from the group consisting of clipping members, ratcheting members, fitting members, adhesive members, clamping members, clamping members and welding members, which are configured to fix the assembly to the inner wall of the fuel tank (2).

4. Assembly according to any one of claims 1 to 3, characterized in that it further comprises an anti-sloshing device (5).

5. An assembly including a bladder (3) for a fuel tank, said bladder (3) comprising: a first configuration in which the bladder (3) is compressed so as to impart a first geometric shape having a first volume to the bladder (3); a second configuration in which the bladder (3) is decompressed so that a second geometric shape having a second volume is imparted to the bladder (3); configured to have the first volume is strictly less than the second volume; Assembly, characterized in that said assembly further comprises an anti-sloshing device (5).

6. 6. An assembly according to claim 5, further comprising a fixing device configured to fix the assembly to an inner wall of the fuel tank (2).

7. 7. The assembly according to claim 6, wherein the fixing device comprises a member selected from the group consisting of clipping members, ratcheting members, fitting members, adhesive members, clamping members, clamping members and welding members configured to fix the assembly to an inner wall of the fuel tank (2).

8. 8. The assembly of any one of claims 5 to 7, wherein the bladder (3) is configured to have a third configuration when compressed such that a third geometric shape having a third volume is imparted to the bladder (3), the third volume being greater than or equal to the first volume and strictly less than the second volume.

9. - fuel tanks (2), - at least one assembly according to any one of claims 1 to 8 extending into the fuel tank (2); 1. A fuel storage system (1) for a heat engine vehicle, comprising: a fuel tank (1) configured to store fuel outside the bladder (3) within the fuel tank.

10. 10. The fuel storage system (1) according to claim 9, further comprising a vent pipe (10) connecting the interior of the bladder (3) with the exterior of the fuel tank (2).

11. 9. Use of at least one assembly according to any one of claims 1 to 8 in a fuel tank (2) of a fuel storage system (1) for a heat engine vehicle, the bladder (3) being intended to suppress a pressure buildup in the fuel tank (2).

12. 9. A manufacturing kit for a fuel storage system (1) for a heat engine vehicle, said system comprising the fuel tank (2) and at least one anti-sloshing device (5) extending inside the fuel tank (2), characterized in that the kit comprises at least one assembly according to any one of claims 1 to 8, wherein the bladder (3) is supported by the at least one anti-sloshing device (5).

13. A heat engine vehicle (20) comprising a fuel storage system (1) according to claim 9 or 10.

14. A method for manufacturing a fuel storage system (1) for a heat engine vehicle, comprising the following steps: a) manufacturing a fuel tank (2); b) manufacturing at least one assembly according to any one of claims 1 to 8; c) maintaining said bladder (3) in a first configuration; d) inserting said at least one assembly into said fuel tank (2) through an opening (6) in the wall (7) of said fuel tank (2); e) fixing said at least one assembly within said fuel tank (2) such that said at least one assembly extends within said fuel tank (2); f) releasing the bladder (3) to transition from the first configuration to the second configuration within the fuel tank (2); A method for manufacturing a fuel storage system (1) for a heat engine vehicle, comprising:

15. 15. The method for manufacturing a fuel storage system (1) for a heat engine vehicle according to claim 14, wherein step e) of fixing the at least one assembly in the fuel tank (2) is performed by clipping (8), ratcheting, fitting, gluing, clamping, clamping or welding the at least one assembly to the inner wall of the fuel tank (2).

16. 16. A method for manufacturing a fuel storage system (1) for a heat engine vehicle according to claim 14 or 15, wherein step c) of holding the bladder (3) in the first configuration is performed by a removable holding device (4).

17. A fuel storage system (1) for a heat engine vehicle, characterized in that it is obtained by implementing the manufacturing method according to any one of claims 14 to 16.

Images