Abstract
A method for manufacturing an internal reinforcement for a motor vehicle tank, the internal reinforcement being designed to connect an upper wall and a lower wall of the tank, is provided. The method includes extruding material forming a so-called extruded portion of the internal reinforcement. An internal reinforcement for a motor vehicle tank obtained by this method is also provided.
Claims
1. A method for manufacturing an internal reinforcement for a motor vehicle tank, the internal reinforcement being designed to connect an upper wall and a lower wall of the tank, the method comprising: a step of extruding material, referred to as extruded material, so as to form a so-called extruded portion of the internal reinforcement.
2. The manufacturing method according to claim 1, further comprising a step of cutting the extruded portion so as to give it its size.
3. The manufacturing method according to claim 2, wherein the step of cutting the extruded portion is performed such that the extruded portion has a cut surface, designed such that when the internal reinforcement is in place in the tank, the cut surface of the extruded portion lies in a plane that is substantially perpendicular to each of the upper and lower walls of the tank.
4. The manufacturing method according to claim 2, wherein the step of cutting the extruded portion is performed such that the extruded portion has a cut surface, designed such that when the internal reinforcement is in place in the tank, the cut surface of the extruded portion lies in a plane that is substantially perpendicular to each of the upper and lower walls of the tank, and the extrusion is carried out by means of an extrusion die having a variable geometry, thus making it possible, for example, to produce an extruded portion having a variable cross-section.
5. The manufacturing method according to claim 1, further comprising a step of producing at least one hole in the extruded portion.
6. The manufacturing method according to claim 1, further comprising a step of overmolding the extruded portion, in particular by means of injection, for example a step of overmolding high-density polyethylene.
7. The manufacturing method according to claim 1, wherein the internal reinforcement comprises two extruded portions and the method comprises a step of assembling the two extruded portions together.
8. The manufacturing method according to claim 7, wherein at least one of the two extruded portions comprises a plurality of means for assembly with the other extruded portion that are distributed in the longitudinal direction of the internal reinforcement so as to be able to vary the longitudinal dimension of the internal reinforcement, the longitudinal direction corresponding to the direction that connects the upper wall and lower wall of the tank when the internal reinforcement is in place in the tank.
9. The manufacturing method according to claim 1, wherein the extruded material comprises two materials which are co-extruded during the extrusion step.
10. An internal reinforcement for a motor vehicle tank obtained by means of a method according to claim 1.
11. The internal reinforcement according to claim 10, comprising a break zone of the internal reinforcement that is designed such that the internal reinforcement can deform or break in the event of an impact, the break zone being chosen from among the elements of the group of: a local narrowing of the extruded portion, a hole made in the extruded portion, a zone arranged between two assembly zones of the extruded portion, each assembly zone being assembled with a polymer matrix provided with reinforcing fibers, means for fusing the extruded portion with another extruded portion of the internal reinforcement or with a wall of the tank.
Description
BRIEF DESCRIPTION OF THE FIGURES
[0053] The invention will be better understood on reading the description which follows, given solely by way of example and with reference to the appended drawings in which:
[0054] FIG. 1 is a schematic perspective view of an internal reinforcement for a motor vehicle tank according to one embodiment of the invention, which connects an upper wall of the tank and a lower wall of the tank which are shown partially.
[0055] FIGS. 2, 3 and 6 are schematic perspective views of internal reinforcements for a motor vehicle tank according to other embodiments of the invention.
[0056] FIG. 4a is a schematic front view of an internal reinforcement according to one embodiment of the invention.
[0057] FIG. 4b is a schematic front view of the same internal reinforcement in which the overmolded portions are not shown.
[0058] FIG. 5c is a schematic front view of an extruded portion intended to be assembled with a second extruded portion so as to form, for example, the various internal reinforcements according to one embodiment of the invention shown from the front in FIG. 5b and FIG. 5a.
[0059] FIG. 7a is a schematic front view of an extruded portion forming an internal reinforcement according to one embodiment of the invention or intended to be assembled with a second extruded portion so as to form, for example, the internal reinforcement according to one embodiment of the invention shown from the front in FIG. 7b.
[0060] FIG. 8 is a schematic view in longitudinal section of an extrusion die for manufacturing extruded portions of internal reinforcements according to another embodiment of the invention.
[0061] FIG. 9 is a partial schematic representation, viewed in longitudinal section, of an extrusion die for manufacturing extruded portions of internal reinforcements according to another embodiment of the invention.
DETAILED DESCRIPTION
[0062] FIG. 1 shows an internal reinforcement of a motor vehicle tank according to one embodiment of the invention and denoted by the reference sign 1. The internal reinforcement 1 connects the upper and lower walls of a motor vehicle tank. Only part 3 of the upper wall and part 5 of the lower wall are shown. The internal reinforcement 1 is manufactured using a method comprising a step of extruding material, referred to as extruded material, so as to form an extruded portion 7. The internal reinforcement 1 has an elongated shape in a longitudinal direction represented by the axis X1-X2. The longitudinal direction is the direction that connects the upper wall 3 and the lower wall 5 of the tank when the internal reinforcement 1 is in place in the tank.
[0063] In all the figures showing an internal reinforcement 1, the axis X1-X2 represents the longitudinal direction, which connects the upper wall 3 and the lower wall 5 of the tank when the internal reinforcement 1 is in place in the tank.
[0064] In the embodiments of FIGS. 1 and 2, the extruded portion 7 has been cut such that the extruded portion 7 has a cut surface 9 (not visible in FIG. 2) which, when the internal reinforcement 7 is in place in the tank, is located in a plane that is substantially parallel to each of the upper 3 and lower 5 walls of the tank. The cut surface 9 is located on a longitudinal end 11 of the internal reinforcement 1. The other longitudinal end of the internal reinforcement is denoted by the reference sign 13.
[0065] In addition, in the embodiment of FIG. 2, the longitudinal ends 11 and 13 of the internal reinforcement 1 are overmolded by a material that is compatible with the material of the extruded portion 7 and the material of the walls 3 and 5 of the tank. In this embodiment, the overmolding 12 is used to secure the extruded portion to the wall of the tank 3 or 5. The overmolded material may be high-density polyethylene (HDPE).
[0066] FIG. 8 shows an extrusion die having a variable geometry. FIG. 8 also shows the extruded material 7′ that is intended to form an extruded portion of an internal reinforcement according to this embodiment of the invention. The axis X1-X2 represents the longitudinal direction, which will connect the upper wall 3 and the lower wall 5 of the tank when the internal reinforcement produced from the extruded material 7′ is in place in the tank. The die 15 of FIG. 8 has an internal diameter which varies between d1 and d2. This makes it possible to produce an extruded portion 7 having a variable cross-section. Therefore, as the extruded portion 7 is cut in a plane that is substantially parallel to the upper 3 and lower 5 walls of the tank, as in the embodiments of FIGS. 1 and 2, it is possible to obtain a variable cross-section such that the reinforcement can perform its functions, in particular that of being assembled with the walls of the tank and optionally the creation of a breaking point for the reinforcement in the event of an impact.
[0067] FIG. 9 shows part of an extrusion die. The axis X1-X2 represents the longitudinal direction, which will connect the upper wall 3 and the lower wall 5 of the tank when the internal reinforcement produced from the extruded material (not shown) is in place in the tank. The die portion shown in FIG. 9 is for example an arm of a die, the cross-section of which is C-shaped, like the die used to form the extruded portion shown in FIG. 7a. As shown in FIG. 9, in this embodiment, the internal diameter of the arm shown varies between e1 and e2, which makes it possible to obtain an extruded portion of which the cross-section is C-shaped and of which, for example, each of the arms has a variable thickness. It is therefore possible to obtain a reinforcement having a variable cross-section such that the reinforcement can perform its functions, in particular that of being assembled with the walls of the tank and optionally the creation of a breaking point for the reinforcement in the event of an impact.
[0068] The internal reinforcements 1 of the embodiments of FIGS. 3, 4a, 4b, 5a, 5b, 6, 7a and 7b comprise an extruded portion 7 which has been cut along a plane parallel to the longitudinal direction, which is represented by the axis X1-X2. Furthermore, in these embodiments, the cut surface is designed such that when the internal reinforcement is in place in the tank, the cut surface of the extruded portion is in a plane that is substantially perpendicular to each of the upper and lower walls of the tank.
[0069] The dies used to obtain the extruded portions of these embodiments have a cross-section of a particular shape, which makes it possible to obtain an extruded portion of which the cross-section has a particular shape that complements the cross-section of the die; in other words, the shape of the cross-section of the extruded portions is dictated by the shape of the cross-section of the dies. This produces a cross-section in the shape of an X (FIG. 3), a T (FIGS. 4a and 4b), a T with side branches (FIGS. 5a and 5b), an I (FIG. 6), a C (FIG. 7b) or an H.
[0070] The use of a die having an X-shaped cross-section advantageously makes it possible to obtain an internal reinforcement 1 having a local narrowing 17 as shown in FIG. 3. The local narrowing 17 constitutes a break zone, which allows the internal reinforcement to deform or to break in the event of an impact, thus preventing rupture of the walls of the tank. In this embodiment, the X-shape is terminated at both ends by a bar 19, 21. This makes it possible to obtain a shape having wider ends 19, 21 in order to ensure the connection to the walls of the tank.
[0071] The internal reinforcement 1 of FIG. 7a has a C-shaped cross-section comprising two arms 23 separated by a central portion 27. The arms 23 form wider ends and the central portion 27 has a smaller cross-section, or local narrowing. Overmolding 29 is used to secure the ends 23 to the lower and upper walls of the tank. The overmolded material may be high-density polyethylene (HDPE).
[0072] The internal reinforcement 1 of the embodiment of FIG. 7b has two extruded portions 7 having a C-shaped cross-section. The two extruded portions 7 are assembled together by means of two holes 31 each made in an arm 23 of each extruded portion 7. The holes 31 allow the extruded portions 7 to be secured to one another, for example allowing molten material (not shown) to pass through in order to achieve securing by strong mechanical anchoring. The securing hole 31 may also allow a screw or a rivet (not shown) to pass through. This makes it possible to easily vary the height of the internal reinforcement, advantageously using the same extrusion die. Furthermore, the means (31) for assembling the two extruded portions (7) together may constitute a break zone for the internal reinforcement 1.
[0073] Similarly, two extruded portions 7 having a T-shaped cross-section are shown assembled together in FIGS. 4a and 4b. The T-shape comprises a rod 33 that is parallel to the longitudinal direction X1-X2 and a rectangular head 35 that is perpendicular to the longitudinal direction X1-X2 and parallel to each of the upper and lower walls of the tank. A hole 31 is made in each of the rods 33 in order to allow them to be assembled together. An overmolding 37 is produced at the level of the holes so as to achieve mechanical anchoring by filling the hole 31 with the molten material 37. The height of the internal reinforcement will easily be varied depending on the height at which the hole is made.
[0074] FIG. 5c shows an extruded portion 7 having a T-shaped cross-section with side branches 39. In order to assemble the two portions 7, as shown in FIGS. 5a and 5b, at least one side branch 39 of one of the extruded portions 7 is brought into abutment with at least one side branch 39 of the other extruded portion 7. Each side branch 39 thus constitutes a means for assembly with the other extruded portion and each extruded portion 7 comprises a plurality of means for assembly with the other extruded portion 7 that are distributed in the longitudinal direction of the internal reinforcement 1. As a result, the longitudinal dimension of the internal reinforcement 1 can be varied.
[0075] FIG. 6 shows an extruded portion 7 having an I-shaped cross-section. Two sheets 41 of polymer matrix provided with reinforcing fibers are assembled on the extruded portion 7 in two distinct assembly zones. The zone 43 provided between the two assembly zones of the extruded portion 7 constitutes a break zone for the internal reinforcement 1.
[0076] It should be understood that a person skilled in the art will be able to envisage a multitude of other embodiments of a reinforcement having an extruded portion as proposed.
