FR3043980A1 - SEAT FIXING ON COMPOSITE FLOOR OF MOTOR VEHICLE - Google Patents

Abstract

The invention relates to a vehicle structure with a cockpit floor receiving a seat. The floor comprising a first composite partition (4) and a second composite partition (6) between which is formed a space traversed by a partition fixing device (4; 6) for anchoring the seat. The fastener has a first threaded portion with a body (14) and a second threaded portion (32) each of which is in contact with an associated partition (4; 6); and a threaded shaft (22) screwed to each of the threaded portions (32) so as to secure the partitions (4; 6) to each other. The threaded shaft (22) is integral and has inverted threads. The attachment device allows a clearance clearance between the partitions (4; 6), which improves the maintenance of the seat during an accident.

Description

SEAT FIXING ON COMPOSITE FLOOR OF VEHICLE

The invention relates to the field of composite vehicle structures. More specifically, the invention relates to a vehicle floor with two composite partitions fixed to one another. The invention also proposes a vehicle. The invention furthermore relates to a method of assembling a vehicle structure.

A motor vehicle structure has several panels connected to each other. These panels sometimes form bodywork elements, separations, or supports. These panels can in particular form the floor of the vehicle, where they are grouped to form caissons improving the rigidity and robustness of the vehicle.

With a view to reducing mass, and therefore reducing carbon dioxide emissions via a reduction in fuel consumption, the panels are advantageously made of polymer matrix composite materials. This solution is also beneficial in the context of an electric vehicle or a hybrid vehicle.

EP 2676869 B1 discloses a lower vehicle structure whose floor forms boxes. The floor, and in particular its boxes are formed by superposed composite partitions. The latter are connected by means of rods having a form of step. Their lower ends include heads glued to the lower wall. The upper ends receive seat rails which are fixed by screws. The upper partition is held between a slide and the associated fixing rods. This architecture provides a certain rigidity of the floor-seat connection since the latter is anchored to each of the partitions.

However, the various manufacturing processes required for the production of composite partitions involve geometric variations at each partition. When the partitions are assembled, their variations accumulate, so that the distance that the stem must reach varies. The contact of the rod can not be optimal with each of the partitions. This penalizes the mechanical strength of the structure, as well as the behavior in case of shock exerting a pulling force on the rod relative to the partitions. The object of the invention is to solve at least one of the problems posed by the prior art. More specifically, the invention aims to provide a vehicle structure with a connection adapting to the geometric variations of said structure. The invention also aims to provide a simple solution, economical, easy to assemble and can be easily controlled. The subject of the invention is a vehicle structure, in particular a vehicle structure floor, the structure comprising: a first partition; a second partition; a device for fixing the partitions, possibly a device for fixing the partitions of equipment such as a vehicle seat; remarkable in that the fixing device comprises two threaded portions, of which a first portion and a second portion, each of which is in contact with one of the two partitions; and a one-piece threaded shaft which is screwed into each of the threaded portions so as to secure the partitions to one another.

According to particular embodiments, the structure may comprise one or more of the following characteristics, taken separately or according to all the possible technical combinations: the threaded axis comprises a surface in contact with the second partition and which is preferably arranged between said partitions; . - The threaded shaft comprises two threaded surfaces, a first scope referred to the first threaded portion and a second threaded seat referred to the second part, the threaded bearing surfaces comprising inverted threads. - The first partition and the second partition define between it a space traversed by the fixing device, the fixing device being mainly disposed in said space, and / or at least one or each of the partitions is made of composite material, in particular with a organic matrix and reinforcing fibers. - The first part comprises a body with a through orifice, said orifice comprising a smaller width section and a widened threaded section to which the threaded axis is screwed, the body being preferably disposed between the first wall and the second wall. - The second part comprises a second plate in contact with the second wall, preferably the second part is disposed outside the walls, and the second part comprises a threaded aperture to which the threaded axis is screwed. - The second partition comprises an opening through which the threaded axis, the opening having an annular clearance surrounding the threaded axis, preferably the threaded portions are spaced apart from each other. - The first part comprises contact surfaces configured to axially block the first partition in both directions. - The second part and the threaded axis each comprise a contact surface, said surface being configured to axially block the second partition in both directions. - The diameter of the first litter is greater than the diameter of the second litter. - The contact surface forms an annular shoulder and / or the second wall comprises a washer in contact with the contact surface of the threaded shaft. - The length of the first staff is less than or equal to the length of the second staff. - The axial length of the thread of the first part, in particular its thread in contact with the threaded axis, is longer than the threading of the second part. - The first part comprises a first plate in contact with the first wall, and possibly against the body. - An axial clearance separates the second partition of the first threaded portion. - The opening is delimited axially, possibly blocked, by the second part and / or by the contact surface. - The contact surface of the threaded shaft comprises a sealing layer in contact with the first partition, preferably the sealing layer comprises an anaerobic resin. - In the normal direction of assembly, each plate and / or each threaded portion is disposed below the associated partition. The material of at least one or of each partition is less dense than the material of the fixing device, preferably at least two times less dense, possibly at least four times less dense. - At least one or each plate comprises an optionally stamped sheet, for example less than or equal to 3.00 mm, preferably less than or equal to 2.00 mm, preferably less than or equal to 1.00 mm. - At least one or each thread forms at least one, preferably at least three turns. The subject of the invention is also a vehicle, in particular an automobile, comprising a structure, which is remarkable in that the structure is in accordance with the invention, preferably the vehicle comprises a seat fixed to the fastening device by means of a screw screw. at the first threaded part.

In a particular embodiment, the body comprises a through orifice, said orifice comprising a threaded section of smaller width to which is screwed the fastening screw of the seat. The invention also relates to a method of assembling a vehicle structure, in particular a vehicle structure floor, the method comprising the following steps, possibly carried out the following order: (a) supply or construction of two partitions and a device for fixing the partitions; (c) fixing the partitions with the fixing device; remarkable in that in step (a) supply or embodiment, the fixing device comprises a one-piece threaded shaft and two threaded portions, one of them being referred to the threaded axis and fixed to one of the two partitions; and in step (c) fixing, the threaded shaft becomes screwed into the other of the two threaded parts so as to be screwed to the two parts simultaneously, preferably the structure is in accordance with the invention. One of the partitions or parts can be heard as the first, and the other as the second.

According to particular embodiments, the structure may comprise one or more of the following characteristics, taken separately or according to all the possible technical combinations: the threaded axis comprises a contact surface, the step (c) fixing comprising an intermediate step; (c2) adjustment where the threaded axis is unscrewed from said one of the threaded portions until the contact surface is in contact with the other of the two partitions. - In step (a) supply or realization, one of the partitions comprises an opening, and the method comprises a step (b) assembly of the partitions, wherein the attachment axis is introduced into the opening. - In step (b) assembly, the partitions are matched, in particular the first part is aligned with the opening. - In step (c) fixing, the gap E between the partitions remains constant.

In general, the particular modes of each object of the invention are also applicable to the other objects of the invention. As far as possible, each object of the invention is combinable with other objects.

The structure allows a simple and robust anchoring of the fastening device to the partitions. The two threaded parts remain distant and non-contact, their connection being simply ensured by the threaded axis. This allows to catch up with finesse the vertical play between the partitions. Moreover, the catch of the game is independent of the thread of the threaded axis since the second part is free in rotation relative to its partition. The use of a shaft with inverted threads, and therefore threaded portions with inverted threads, makes it possible to tighten the second partition. Indeed, as soon as the contact surface of the threaded shaft is pressed against the upper surface of the second partition, the clamping of the second threaded portion tends to further tighten the contact surface against the partition. Thus, it is not necessary to maintain the threaded axis during the clamping of the second part, which simplifies the assembly operation.

The applications of the plates against the partitions limit the mechanical clearances and the prestresses, which improves the behavior in the event of impact.

Intrinsically, the plates evenly distribute their tearing forces on the composite partitions. Passenger safety is improving.

The fastener has a reduced number of parts, which becomes economical in more than one way. This reduced number of entities allows faster assembly, and lightening reducing the consumption of the associated vehicle. The reduction and simplification of the interfaces improves the reliability of the device, and allows easy control. Other features and advantages of the present invention will be better understood from the description given by way of example and with reference to the drawings among which:

Figure 1 shows a step of assembling the partitions of the structure according to the invention.

Figure 2 shows a step of attachment of the second part on the threaded shaft according to the invention.

Figure 3 shows a step of adjusting the contact surface of the threaded shaft according to the invention.

Figure 4 shows a vehicle structure with a seat rail according to the invention.

FIG. 5 illustrates a method of assembling a vehicle structure according to the invention.

In the following description, the axial term refers to a direction in the screwing-unscrewing direction of the threaded axis. The figures and the description are with reference to horizontal partitions, however the invention can also be applied to vertical or inclined partitions.

Figure 1 shows a subset of a vehicle structure 2 with partitions (4; 6). In this case, it is a vehicle floor. FIG. 1 illustrates a step of assembling the partitions (4; 6) of an assembly process which will be presented in FIG.

The structure 2 has two partitions both made of composite materials. These composites each comprise a fiber reinforcement densified by an organic matrix, which significantly reduces the weight of the structure. The reinforcement may comprise woven or non-woven plies, based on glass fibers, carbon fibers, graphite fibers, or any equivalent material. The matrix can be epoxidic, and can show fillers to improve its physicochemical properties. The partition 4 of the top, said first partition 4 can be monobloc; optionally the lower partition 6, said second partition 6, is a laminate with several adhesive composite layers. Optionally, one or both partitions are metallic.

The partitions (4; 6) are here represented in an assembled configuration. The second partition 6 is shown in dashed lines before assembly. After production or supply, they are close to each other. They may show junction zones (not shown) where they are in contact and possibly fixed to each other, for example so as to form a structure similar to that of EP 2676869 B1. The partitions (4; 6) form between it an empty space 8 so as to form a box.

The structure 2 comprises a device 10 for fixing the partitions (4; 6), only a subset of the device being shown here. This subassembly shows a first threaded portion 12 fixed to the first partition 4. The threaded portion comprises a body 14, a first plate 16 and possibly a retaining washer 18. The latter (16; 18) provide distribute forces, but may be replaced by glue on the body 14. The latter includes a through hole 20, where several sections are distinguished by their diameters. The orifice 20 may be threaded to form threads therein. The widest section, that is the bottom, receives a threaded shaft 22 which is pre-mounted. The threaded shaft 22 can be monobloc to be more resistant and more reliable. It has two threaded bearing surfaces (24; 26) of different diameters and separated by a contact surface 28 facing the second partition 6. The lengths and / or the diameters of the threaded bearing surfaces (24; 26) vary, as does the orientation of their threads. One has a step to the left, the other a step to the right. Alternatively, the threaded bearings include threads of the same direction.

During assembly, the free end of the bottom threaded surface, called the second bearing surface 26, passes through an opening 30 of the second partition 6. The free ends of the threaded bearing surfaces (24; 26) of the threaded shaft 22 are arranged on either side of the second partition 6. The first threaded portion 12 and / or the contact surface 28 remain at an axial distance from the second partition 6. In the opening 30, an annular clearance surrounds the second threaded surface 26, which allows adjustment in the XY plane, the horizontal plane of the vehicle. An adaptation to a positioning variation of the partitions (4; 6) is therefore allowed.

Figure 2 shows the attachment of the second threaded portion 32 to the lower end of the threaded shaft 22. The second portion 32 is drawn in dashed lines before mounting.

The second threaded portion 32 may be a plate. It has a threaded aperture 34 to which is screwed the threaded shaft 22. Since the aperture 34 is through, it becomes possible to visually control the mounting of the threaded shaft 22. The second portion 32 may comprise a stamped sheet forming a second platinum 36, the edges of which have fallen to stiffen it. It can be disk-shaped drilled with a welded nut at its center, or could be monoblock and cut in the mass.

The second threaded portion 32 is screwed to the second bearing 26 from the outside of the space 8 between the partitions (4; 6). It is turned to the level of the second partition 6. Therefore, the fastening device 10 passes through the space 8 and is held vertically from outside the partitions (4; 6). The second portion 32 may be substantially off-axis with respect to the opening 30, and may close one side.

Figure 3 shows the threaded shaft 22 in annular contact of the second partition 6 via its contact surface 28. The threaded shaft 22 is rotated and lowered.

To reach this state, the threaded shaft 22 is partially unscrewed from the first part 12, while maintaining an engagement with the latter. Through this, it remains possible to transmit efforts to their junction. The contact surface 28 of the threaded spindle 22 touches and engages the surface opposite the second partition 6. Vertical forces can be communicated from one partition (4; 6) to the other. In parallel, the second part 32 is revived. In doing so, the vertical gap E between the partitions (4; 6) remains constant.

The contact surface 28 may be a shoulder in annular contact with the edge of the opening. It can be formed on a disk, of greater diameter than each threaded surface (24; 26). The disc can hide the second partition 6 of the body 14 thanks to its diameter which is greater than that of the body 14, in addition to being greater than the diameter of the opening 30. Despite the evocation of diameters, the shoulder and / or, the opening 30 and / or the body 14 may show other profiles; such as cams, squares, hexagons, or any suitable form. The contact surface 28 closes another side of the opening 30, so that it becomes a closed cavity, for example a torus around the second bearing surface 26.

In the state shown, each plate (16; 36) matches its associated partition (4; 6), for example by virtue of the majority or the totality of its dedicated contact surface. Being below the associated bulkheads (4; 6), they consistently resist an upward pulling force, as generated by a vehicle crash. The monobloc aspect of the threaded shaft is not essential to the invention. Indeed, the disk can be reported around the threaded axis and come into contact with the contact surface.

Figure 4 outlines equipment 38 mounted to the structure 2 of the vehicle. The equipment 38 can be a position adjustment rail of a seat. The connection between the fixing device 10 and the equipment 38 is provided by a screw 40 which is aimed in the orifice 20 of the body 14 of the first threaded portion 12. The rail can rest against the upper surface of the washer 18 allowing to block the first part 12 to its partition 4.

The vehicle structure 2 may comprise several seats fixed to its floor. They are anchored by means of several screws 40 each fixed in a fastening device 10 as previously described. At least one or each plate 16 is wider than the rail.

FIG. 5 represents a diagram of a method of assembling a vehicle structure, in particular the structure that has been presented in relation to FIGS. 1 to 4.

The method may comprise the following steps, possibly carried out in the following order: (a) supply or production 100 of two partitions and a device for fixing the partitions; (b) assembling the partitions 102 so that they come into contact with one another, and by passing through the opening of the second partition with the second bearing surface of the threaded axis, this step being represented in FIG. figure 1 ; (c) fixing 104 of the fixing device so as to fix the partitions to one another; (D) mounting 106 of an equipment on the fixing device, this step being shown in FIG. 4. This step is optional because the fixing device is sufficient to join the partitions between them.

The first threaded portion can be mounted to the first partition. It can be attached via its washer which is crimped at a tubular end of the body. Similarly, the first plate can be fixed to the body for example by welding, or be glued to the first partition. These fasteners can be performed during step (a) supply or embodiment 100, or during step (b) assembly 102. The threaded axis is previously connected to the first part, and therefore to the first partition. So far, the second threaded portion is detached from each partition and the threaded shaft.

Due to the size of the opening of the second partition, it is possible to make up the misalignment of the threaded axis during (b) assembly 102, the alignment being understood in the plane of the second partition. This opening size and the clearance that surrounds the axis also allow a crossing of the opening by presenting the threaded axis crosswise; which simplifies assembly. The step (c) fixing 104 may comprise the following intermediate steps: - (c1) attachment 108 of the second threaded portion on the threaded axis, for example by screwing it on the second threaded surface until it comes into contact with the second partition, this being illustrated in FIG. 2; then - (c2) adjustment 110 of the threaded axis so that its contact surface touches the second partition, this being represented in FIG. 3. This step can be replaced by a bonding of the threaded spindle to the second part , which makes it possible to dispense with the contact surface and / or inverted threads. In step (c2) adjustment 110, the threaded axis is unscrewed from the first threaded portion, it therefore leaves the latter and gradually leaves the inter-partition space. A tool through the orifice of the body rotates the threaded shaft from outside the partitions. Its free end moves away from the partitions. During step (c2) adjustment 110, the second part can also be unlocked and then revived. Optionally, the intermediate step (c2) adjustment 110 is performed before the intermediate step (c1) attachment 108 of the second threaded portion. These steps can be simultaneous. The order of the steps can be reversed. The steps (c) fixing 104 and (d) mounting 106 can be performed simultaneously.

Claims (10)

claims Vehicle structure (2), in particular a vehicle structure floor (2), the structure (2) comprising: a first partition (4); a second partition (6); - a fixing device (10) of the partitions (4; 6), possibly a fixing device (10) to the partitions (4; 6) of a device (38) such as a vehicle seat; characterized in that the fastening device (10) comprises two threaded portions (12; 32), of which a first portion (12) and a second portion (32), each of which is in contact with one of the two partitions (4). 6); and a one-piece threaded shaft (22) which is screwed into each of the threaded portions (12; 32) so as to secure the partitions (4; 6) to each other. 2- Structure (2) according to claim 1, characterized in that the threaded shaft (22) comprises a contact surface (28) of the second partition (6) and which is preferably arranged between said partitions (4; 6) . 3- Structure (2) according to one of claims 1 to 2, characterized in that the threaded shaft (22) comprises two threaded bearing surfaces (24; 26), a first bearing surface (24) referred to the first threaded portion (12) and a second threaded bearing (26) referred to in the second portion (32), the threaded bearing surfaces (24; 26) including inverted threads. 4- Structure (2) according to one of claims 1 to 3, characterized in that the first partition (4) and the second partition (6) define therebetween a space (8) traversed by the fixing device (10) , the fastening device (10) being mainly disposed in said space (8), and / or at least one or each of the partitions (4; 6) is made of composite material, in particular with an organic matrix and reinforcing fibers. 5- structure (2) according to one of claims 1 to 4, characterized in that the first portion (12) comprises a body (14) with through hole (20), said orifice (20) comprising a shorter section width and a widened threaded section to which the threaded shaft (22) is screwed, the body (14) being preferentially disposed between the first partition (4) and the second partition (6). 6- Structure (2) according to one of claims 1 to 5, characterized in that the second portion (32) comprises a second plate (36) in contact with the second partition (6), preferably the second portion (32) is disposed outside the partitions (4; 6), and the second portion (32) comprises a threaded aperture (34) to which the threaded axis (22) is screwed. 7- Structure (2) according to one of claims 1 to 6, characterized in that the second partition (6) comprises an opening (30) traversed by the threaded shaft (22), the opening (30) having a annular clearance surrounding the threaded axis (22), preferably the threaded portions (12; 32) are spaced apart from each other. 8- Vehicle, especially automobile, comprising a structure (2), characterized in that the structure (2) is according to one of claims 1 to 7, preferably the vehicle comprises a seat fixed to the fastening device (10) to using a screw (40) screwed to the first threaded portion (12). 9- A method of assembling a vehicle structure (2), especially a vehicle structure floor (2), the method comprising the following steps, possibly carried out the following order: (a) supply or production (100) two partitions (4; 6) and a fixing device (10) of the partitions (4; 6); (c) securing (104) the partitions (4; 6) with the fastening device (10); characterized in that in the step (a) of providing or making (100) the fastening device (10) comprises a one-piece threaded shaft (22) and two threaded portions (12; 32), one of which being referred to the threaded axle (22) and attached to one of the two partitions (4; 6); and in step (c) fixing (104), the threaded shaft (22) becomes screwed into the other of the two threaded portions (12; 32) so as to be screwed to the two parts simultaneously, preferably the structure (2). ) is according to one of claims 1 to 7. 10-Process according to claim 9, characterized in that the threaded shaft (22) comprises a contact surface (28), the step (c) fixing (104) comprising an intermediate step (c2) adjustment (110) where the threaded shaft (22) is unscrewed from said one of the threaded portions (12) until the contact surface (28) is in contact with the other of the two partitions (6).