Frame for motor vehicle tank

Abstract

To provide an assembly comprising a frame for a plastic tank for a motor vehicle having an increased ability to adapt to variations in the dimensions of the tank during the manufacture of the tank, and exhibiting improved resistance to compression and stretching.SOLUTION: A reinforcement 1 for a plastic tank for a motor vehicle comprises means 10 for fixing an inner reinforcing element 2 of the tank that is intended to connect two opposite walls of the tank. The means for fixing the inner reinforcing element comprises a first structure configured to snap-fit a portion of the inner reinforcing element. The first structure comprises: two bodies movable relative to each other, each movable body being provided with holding means configured to hold the inner reinforcing element in a direction opposite to a snap-fitting direction; and at least one stop element protruding in a direction opposite to the snap-fitting direction in order to provide a stopper for the inner reinforcing element when the inner reinforcing element is snap-fit into place.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to the technical field of plastic tanks for motor vehicles, in particular liquid fuel tanks.The present invention generally relates to a frame for a plastic tank for a motor vehicle, comprising at least one means for fastening an internal reinforcing element of the tank.

[0002] In particular, the invention relates to a frame for a plastic tank for a motor vehicle, comprising at least one means for fastening an internal reinforcing element for the plastic tank for a motor vehicle.

[0003] The present invention also relates to an assembly configured to be fixed to the interior of a plastic tank for a vehicle, comprising the frame and at least one internal reinforcing element, and further to a plastic tank for a vehicle comprising the assembly. The present invention also relates to a method for manufacturing a plastic tank for a vehicle. [Background technology]

[0004] Plastic fuel tanks obtained by extrusion blow molding of parisons are During use, the material is first cooled after removal from the mold, which causes it to shrink. or during its use or at the end of its useful life, especially due to excess pressure or pressure drop of the contents. During this time, the dimensions change, either due to its thermal expansion or due to its aging.

[0005] It is known to insert internal reinforcing elements into the tank during its manufacture, the purpose of which is to increase the resistance of the plastic tank to the mechanical stresses to which it will be subjected during its service life.

[0006] For example, US Pat. No. 5,699,499 discloses an assembly including a frame and a connecting element to the bulkhead of the tank, the connecting element having a low stiffness and not allowing to ensure an internal reinforcement function, the frame also including a structure that is deformable not only in the longitudinal direction X of the vehicle to which the frame is oriented and in the transverse direction Y of the vehicle, but also along the vertical direction Z of the vehicle. However, such an assembly has a rather limited ability to adapt to dimensional changes of the tank. Moreover, such an assembly has too low resistance to compression and elongation in the vertical direction of the vehicle. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] US Patent Application Publication No. 2011 / 0226777 Summary of the Invention [Problem to be solved by the invention]

[0008] The present invention is particularly aimed at alleviating these shortcomings of the prior art.

[0009] To this end, the invention aims to provide an assembly comprising a frame for a plastic tank for a motor vehicle, the assembly also comprising at least one internal reinforcing element, said assembly having an increased ability to adapt to dimensional changes in the tank, in particular during its manufacture, and having improved resistance to compression and elongation.

[0010] More precisely, the object of the invention, in at least one of its embodiments, is to provide a frame comprising fixing means adapted to fix at least one internal reinforcing element, such that the frame and the at least one internal reinforcing element are able to form an assembly having an increased ability to adapt to dimensional variations of a plastic tank for a motor vehicle, in particular during the manufacture of said tank.

[0011] It is a further object of the present invention, in at least one of its embodiments, to provide a plastic tank for an automobile.

[0012] Another object of the present invention is, in at least one of its embodiments, to use a method for manufacturing a plastic tank for an automobile. [Means for solving the problem]

[0013] According to a particular embodiment, the invention relates to a frame for a plastic tank for a motor vehicle, comprising at least one means for fixing an internal reinforcing element of the tank.

[0014] According to the invention, the at least one means for fixing the internal reinforcing element comprises at least one first structure configured to snap onto at least a part of the internal reinforcing element, said at least one first structure comprising at least two mutually movable bodies each comprising a holding means configured to hold the internal reinforcing element in a direction opposite to the snap-in direction, and at least one element forming a stopper that protrudes in a direction opposite to the snap-in direction to provide a stop for the internal reinforcing element when it is snap-in.

[0015] The general principle of the present invention is based on the presence of means for fixing the internal reinforcing element, which simultaneously allow snapping in at least a portion of the internal reinforcing element and maintain the reinforcing element in place after snapping in, in order to ensure a fixation with increased resistance to the mechanical stresses to which the assembly is subjected during the tank's manufacture and an increased ability to adapt to dimensional changes in the tank. The at least one first structure comprises at least two mutually movable bodies, each of which is provided with a retaining means configured to hold the internal reinforcing element in a direction opposite to the snap-in direction, and the presence of at least one element forming a stopper, which allows snapping in at least a portion of the internal reinforcing element and protrudes in a direction opposite to the snap-in direction, provides a stopper for the internal reinforcing element when it is snapped in. It is understood that this element forming the stopper is an element distinct from the movable body, i.e., the retaining means configured in particular to hold the internal reinforcing element in a direction opposite to the snap-in direction, is not to be confused with the element forming the stopper.

[0016] Preferably, the element forming the stopper makes it possible to maintain the reinforcing element after snapping in. At least part of the internal reinforcing element is maintained in place after snapping in and is clamped by a combination of retention means present on the movable body, configured to hold the internal reinforcing element in a direction opposite to the snapping direction, and the retention ensured by the at least one element forming the stopper. Moreover, after snapping in, at least part of the internal reinforcing element is likewise maintained in place by the force exerted by the at least two movable bodies.

[0017] The present invention thus rests on a completely new and inventive approach to fastening means that allows increasing the capacity of an assembly comprising a frame and at least one internal reinforcing element to adapt to dimensional changes in the tank and allows reducing the stresses caused by the presence of said assembly in the tank. Such an arrangement limits the relative movements between the two members, in particular in the two axes parallel to the welding plane. Such an interconnection created between the internal reinforcing element and the frame makes it possible to ensure improved centering and fastening of the two members.

[0018] The expression "internal reinforcing element" is meant to designate an element of the structure for connecting two opposing bulkheads of the tank. The internal reinforcing element makes it possible to limit the deformation of the tank when pressure is applied. The internal reinforcing element is preferably welded to the plastic tank at both ends.

[0019] The term "tank" is intended to refer to a sealed tank capable of storing liquid fuel in a variety of different uses and environmental conditions. The tank according to the present invention is generally made of a plastic bulkhead including an inner surface at its concave portion and an outer surface at its convex portion. Preferably, the tank is a plastic liquid fuel tank.

[0020] The expression "a first structure configured to snap-fit ​​at least a part of the internal reinforcing element" is meant to indicate that at least a part of the reinforcing element, preferably the entire reinforcing element, is locked by the fixing means and prevented from moving after snap-fit ​​by being clamped between the retaining means present on the mobile body and at least one element forming the stopper.

[0021] Advantageously, at least one element forming the stopper has two faces, namely a first face for forming an axial abutment face for the internal reinforcing element in the snap-in direction and a second face for forming a radial abutment face for the internal reinforcing element in the direction of rotation of the internal reinforcing element around an axis parallel to the axial abutment axis.

[0022] Advantageously, at least one element forming the stop is configured to fit into a receiving portion of the internal reinforcing element so that, after snapping in, the latter is rotationally locked, it being understood that this receiving portion may in particular consist of a special receiving shape provided in the internal reinforcing element.

[0023] Advantageously, the frame for a plastic tank for a motor vehicle according to the invention is such that the at least one first structure is configured to snap onto at least one inner part of the internal reinforcing element.

[0024] In this way, the first structure configured to snap onto at least one inner part of the internal reinforcing element allows for improved fixation of the internal reinforcing element, and the movable body ensures that the movement of the internal reinforcing element is limited in all directions. In fact, the force exerted by the movable body on the interior of the internal reinforcing element can be so in a great many directions.

[0025] The expression "inside the internal reinforcing element" is meant to refer to hollowed-out portions of the material of the internal reinforcing element, such as for example through holes or blind holes.

[0026] According to a preferred embodiment, the frame for a plastic tank for a motor vehicle according to the invention is such that the first structure is configured to snap onto at least one outer part of the internal reinforcing element.

[0027] In this way, the first structure configured to snap-fit ​​at least one outer part of the internal reinforcing element allows the fixing strength of the internal reinforcing element to be reduced in the welding direction of the internal reinforcing element while ensuring an increased fixing strength of the internal reinforcing element in other directions, and the movable body is coupled with the outer part of the internal reinforcing element that is not located at the welding location.

[0028] The expression "the movable body is coupled to the exterior of the internal reinforcing element that is not located at the welding location" is meant to indicate that the movable body is in contact with and exerts pressure on the exterior of the internal reinforcing element that is not located at the welding location.

[0029] According to a preferred embodiment, the frame for a plastic tank for a motor vehicle according to the invention is such that at least two bodies movable relative to one another are tongues.

[0030] Thus, the movable bodies relative to one another having the shape of tongues make it possible to obtain a good compromise between the stiffness and flexibility of the movable bodies.

[0031] According to a preferred embodiment, the frame for a plastic tank for a motor vehicle according to the invention is such that the holding means adapted to hold the internal reinforcing element are in the form of a cut-out or protrusion.

[0032] In this way, the holding means configured to hold the internal reinforcing element can take the form of a cutout or protrusion, making it possible to have a movable body that is even easier to manufacture.

[0033] According to a preferred embodiment, the frame for a plastic tank for a motor vehicle according to the invention is such that at least one element forming the stopper comprises a rod, preferably a ribbed rod, which advantageously has an X, U, V or W shape.

[0034] In this way, the element forming the stopper including a rod allows for easier positioning and adjustment of the stopper. By "rod" is meant a member that extends along a major axis and protrudes from the face of the first structure at this axis.

[0035] According to a preferred embodiment, the frame for a plastic tank for a vehicle according to the invention is based on a material selected from the group consisting of high density polyethylene (HDPE), polyoxymethylene (POM), polyamide (PA), polyphthalamide (PPA), polyketone (PK), and preferably has the shape of a single piece.

[0036] According to a preferred embodiment, the frame for a plastic tank for a vehicle according to the invention is adapted to include support means for fuel tank components, such as vent or liquid lines, valves such as flap valves, roll-over valve (ROV) type valves, or full limit vent valve (FLVV) type valves, temperature sensors, level sensors, or quality sensors. The frame may also include or serve as a deflector, also known as an anti-noise baffle or anti-slosh baffle. Preferably, the fuel tank and / or deflector components are fixed to the frame by "clippage." In this way, the "clippage" allows for easy fixing and handling of the fuel tank and / or deflector components relative to the frame.

[0037] According to a preferred embodiment, the frame for a plastic tank for a motor vehicle according to the invention comprises a deformable connecting member connecting the frame and at least one means for fixing an internal reinforcing element, said connecting member being configured to be deformed under the influence of an external mechanical stress on the frame in order to allow relative movement between the frame and the at least one means for fixing an internal reinforcing element.

[0038] In this way, the deformable connecting members make it possible to reduce the stresses on the frame, which are related to temperature and pressure changes inside the tank, which cause deformations due to the movement of the internal reinforcing elements relative to one another. If no deformable connecting members are present on the frame, and therefore between the frame and one or more internal reinforcing elements, these movements would cause stresses on the frame. Preferably, the deformable connecting members allow deformation in an axis parallel to the welding plane of the internal reinforcing elements relative to the tank.

[0039] According to a preferred variant, the frame for a plastic tank for a motor vehicle comprises a receiving part configured to receive an insertion means, such as an insertion stick, used for example during the production of the tank in order to insert the assembly including the frame into the parison, said receiving part advantageously taking the form of a hole or a blind hole.

[0040] According to a preferred variant, the frame for a plastic tank for a motor vehicle is adapted to include a plurality of through holes. Preferably, the frame is also provided with stiffening means such as ribs.

[0041] Thus, the presence of through holes in the frame allows for easier movement of the liquid contained in the tank, and the presence of stiffening means on the frame allows the frame to better resist the stresses associated with the fastening of components to the frame and the stresses to which the frame is subjected in the fuel tank.

[0042] Another object of the present invention is to provide an assembly for a plastic tank for a vehicle, comprising a frame for the tank according to the present invention and an internal reinforcing element configured to be snap-fitted to the frame. Preferably, the internal reinforcing element has the shape of a column, preferably cylindrical, or a diabolo, or a retainer. Preferably, the retainer includes a bulkhead with a central cutout, a portion of the bulkhead including a reinforcing rib. The bulkhead of the retainer may be flat or curved. The reinforcing element preferably includes two parts overmolded on their two ends with a material that can be welded to the bulkhead of the tank. The internal reinforcing element preferably consists of a core based on polyoxymethylene (POM), polyphthalamide (PPA), polyketone (PK), polyamide (PA), or metal, and two parts overmolded with high-density polyethylene (HDPE). The internal reinforcing element preferably includes a mechanically weak area that can cause the element to fracture when subjected to high stresses resulting from pressure exerted on the tank. This mechanically weakened area may be in the form of a thin cross section, at least one notch or a thin septum.The internal reinforcing element may comprise a hollow, in particular in the centre of the reinforcing element.

[0043] Another object of the present invention is to provide a plastic tank for a motor vehicle, comprising an assembly for a plastic tank for a motor vehicle according to the invention.

[0044] An object of the present invention is also to provide a method for manufacturing a plastic tank for an automobile.

[0045] According to an advantageous implementation of the method for manufacturing a plastic tank for a motor vehicle according to the invention, said method comprises a step of fastening, more precisely a snap-fitting, of an internal reinforcing element to a frame for a plastic tank for a motor vehicle according to the invention.

[0046] Other characteristics and advantages of the invention will appear more clearly on reading the following description of preferred embodiments, given by way of illustrative and non-limiting example only, and the accompanying drawings, in which: [Brief explanation of the drawings]

[0047] [Figure 1] 1 shows an assembly for a plastic tank for an automobile according to the present invention. [Figure 2] 1 illustrates a means for fixing an internal reinforcing element of a frame according to the invention. [Figure 3] 1 illustrates the connection between an internal stiffening element and a frame according to the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0048] 1 shows an embodiment of an assembly 4 for a plastic tank for a vehicle according to the invention, comprising a frame 1 and an internal reinforcing element 2. The internal reinforcing element 2 is intended to connect two opposing bulkheads of the tank. The frame 1 for a plastic tank for a vehicle comprises at least one means 10 for fastening the internal reinforcing element 2 to the tank. The frame 1 comprises a deformable connecting member 11 connecting the frame 1 and the means 10 for fastening the internal reinforcing element 2, said connecting member 11 being deformable under the influence of an external mechanical stress on the frame 1 to allow relative movement between the frame 1 and the means 10 for fastening the internal reinforcing element 2. The frame 1 also comprises a receiving portion 12 configured to receive an insertion means, such as an insertion stick, for inserting the assembly 4 into a parison during the production of the tank. The receiving portion 12 advantageously has the shape of a hole or a blind hole. The frame 1 is primarily made of a material selected from the group consisting of high-density polyethylene (HDPE), polyoxymethylene (POM), polyamide (PA), polyphthalamide (PPA), and polyketone (PK). The frame 1 also includes support means 3 for fuel tank components, such as a pump, a level sensor, a pressure sensor, a temperature sensor, and valves such as flap valves, roll-over valve (ROV) type valves, or fill-limit vent valve (FLVV) type valves, or ventilation and fuel lines. The frame 1 also includes a plurality of through-holes 13. Preferably, the frame 1 also includes stiffening means, such as ribs (not shown). The internal reinforcing element 2 preferably has the shape of a cylindrical column 21 or a diabolo. The internal reinforcing element 2 may also have the shape of a retaining portion 20, which includes a partition with a central cutout, part of which includes a reinforcing rib. The partition of the retaining portion may be flat or curved. Said reinforcing element 2 preferably comprises two parts overmolded on its two ends with a material that can be welded to the bulkhead of the tank.The internal reinforcing element 2 preferably comprises a core based on polyoxymethylene (POM), polyphthalamide (PPA), polyketone (PK), polyamide (PA) or metal and two sections overmolded with high density polyethylene (HDPE). The internal reinforcing element preferably comprises mechanically weak areas that could cause the element to fracture when subjected to high stresses arising from the pressure exerted on the tank.

[0049] 2 shows a means 10 for fastening an internal reinforcing element of a tank to a frame 1. The means 10 comprises at least one first structure 100 configured to snap onto at least a part of the internal reinforcing element, the at least one first structure comprising at least two mutually movable bodies 1000 in the form of tongues 10000, each movable body 1000 comprising a holding means 10001 configured to hold the internal reinforcing element 2 in the direction opposite to the snap-in direction, the holding means 10001 having the form of a protrusion, and at least one element 1001 forming a stopper comprising a U-shaped rod. The element 1001 forming a stopper protrudes in the direction opposite to the snap-in direction to provide a stop for the internal reinforcing element 2 when the internal reinforcing element 2 is snapped onto the first structure 100. The stopper-forming element 1001 combined with the retaining means 10001 forms a clamping portion such that, after snapping, at least a portion of the internal reinforcing element 2 is kept in place and clamped by the combined retention ensured by the retaining means 10001 and the at least one stopper-forming element 1001. The stopper-forming element 1001 has at least two abutment surfaces: a first surface for forming an axial abutment surface for the internal reinforcing element 2 in the snap-in direction, and a second surface for forming a radial abutment surface for the internal reinforcing element 2 in the direction of rotation of the internal reinforcing element 2 around an axis parallel to the axial abutment axis. More precisely, in the embodiment of Fig. 2, the axial abutment surface corresponds to a U-shaped front surface of the element 1001 extending substantially parallel to the rear surface of the first structure 100, and the radial abutment surface corresponds to one or more surfaces of the element 1001 extending substantially perpendicular to the rear surface of the first structure 100.

[0050] 3 illustrates a connection between an internal reinforcing element 2 according to the invention and a frame 1, which forms part of an assembly for a plastic tank for a motor vehicle according to the invention. The connection is made using a means 10 including at least one first structure 100 configured to snap onto at least a portion of the internal reinforcing element 2, the at least one first structure 100 including four tongue-shaped movable bodies 1000, each of which has a retaining means 10001 configured to hold the internal reinforcing element 2 in the direction opposite to the snap-on direction, the retaining means 10001 having the shape of a protrusion, and at least one element forming a stop. The first structure 100 is configured to snap onto at least one interior 200 of the internal reinforcing element 2. The internal reinforcing element 2 has the shape of a retaining part 20 including a partition 201 with a central cutout 200, part of which includes a reinforcing rib 2010. The partition of the retaining part is curved. The reinforcing element preferably comprises two parts overmolded on its two ends with a material that can be welded to the bulkhead of the tank. The internal reinforcing element preferably comprises a central part 202 based on polyoxymethylene (POM), polyphthalamide (PPA), polyketone (PK), polyamide (PA) or metal, and two parts 203, 204 overmolded with high density polyethylene (HDPE). The internal reinforcing element preferably comprises mechanically weak areas that could cause the element to fracture when subjected to high stresses arising from the pressure exerted on the tank. [Explanation of symbols]

[0051] 1 frame 2 Internal reinforcement elements 3 Support means 4 Assembly 10 Fixing means 11 Connecting member 12 Receiving part 13 Through hole 20 Holding part 21 pillars 100 1st structure 200 Central cutout 201 Bulkhead 202 Center 203, 204 Parts overmolded with high density polyethylene (HDPE) 1000 moving objects 1001 Elements forming the stopper 2010 Reinforcement rib 10000 Tongue 10001 Holding means

Claims

1. A frame (1) for a plastic tank for an automobile, the frame (1) comprises at least one means (10) for fixing an internal reinforcing element (2) of the tank for connecting two opposing bulkheads of the tank, said at least one means (10) for fixing said internal reinforcing element (2) comprises at least one first structure (100) configured to snap-fit ​​at least a portion of said internal reinforcing element (2); At least one of said first structures (100) comprises: at least two mobile bodies (1000) flexible in a predetermined direction relative to each other, each of which comprises a holding means (10001) adapted to hold said internal reinforcing element (2) in a direction opposite to the snap-in direction; at least one stop-forming element (1001) different from said mobile body (1000) that projects in the direction opposite to the snap-in direction in order to provide a stop for said internal reinforcing element (2) when said internal reinforcing element is snapped in; Including, A frame (1), characterized in that at least one said first structure (100) is configured to snap-fit ​​onto an inner part of said internal reinforcing element (2).

2. 2. A frame (1) for a plastic tank for a motor vehicle according to claim 1, wherein the at least one stopper-forming element (1001) combined with the retaining means (10001) forms a clamping portion such that after snap-fitting, at least a portion of the internal reinforcing element (2) is kept in a fixed position and clamped by the combined retention ensured by the retaining means (10001) and the at least one stopper-forming element (1001).

3. A frame (1) for a plastic tank for an automobile as described in claim 1, wherein at least one of the first structures (100) is configured to snap-fit ​​from the outside of at least one of the internal reinforcing elements (2).

4. A frame (1) for a plastic tank for an automobile as described in claim 1, wherein at least two of the movable bodies (1000) relative to each other are tongue portions (10000), the tongue portions protruding from the first structure (100) and having the shape of the tongue portions.

5. 2. A frame (1) for a plastic tank for a motor vehicle according to claim 1, wherein the retaining means (10001) adapted to retain the internal reinforcing element (2) are in the form of protrusions.

6. 2. A frame (1) for a plastic tank for a motor vehicle according to claim 1, wherein the element (1001) forming the at least one stop consists of a rod protruding from the surface of the first structure (100).

7. A frame (1) for a plastic tank for an automobile as described in claim 1, including support means (3) for supporting components of the fuel tank such as ventilation or liquid lines, valves, temperature sensors, level sensors, pressure sensors or quality sensors.

8. A frame (1) for a plastic tank for an automobile as described in claim 1, wherein the frame (1) is provided with at least one component selected from a noise prevention baffle or anti-slosh baffle, a valve, an air or liquid line, a temperature sensor, a level sensor, a pressure sensor or a quality sensor.

9. At least one means (10) for fixing the internal reinforcing element (2) consists of a different member fixed to the frame (1), 2. A frame (1) for a plastic tank for a motor vehicle according to claim 1, wherein the frame (1) comprises a deformable connecting member (11) connecting the frame (1) and the at least one means (10) for fixing the internal reinforcing element (2), the connecting member (11) being configured to be deformed under the influence of an external mechanical stress on the frame (1) in order to allow relative movement between the frame (1) and the at least one means (10) for fixing the internal reinforcing element (2).

10. An assembly (4) for a plastic tank for an automobile, comprising a frame (1) for a plastic tank for an automobile as described in any one of claims 1 to 9, and an internal reinforcing element (2) configured to be snap-fitted to the frame (1).

11. said internal reinforcing elements being selected from posts (21) and retainers (20); 11. The assembly (4) for a plastic tank for an automobile according to claim 10, wherein the retaining portion (20) includes a partition wall (201) having a central cutout (200), and a portion of the partition wall (201) includes a reinforcing rib (2010).

12. A plastic tank for an automobile, comprising an assembly (4) for a plastic tank for an automobile as described in claim 10.

13. 10. A method for manufacturing a plastic tank for a motor vehicle, comprising the step of snapping an internal reinforcing element (2) onto a frame (1) for a plastic tank for a motor vehicle according to any one of claims 1 to 9.

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