Motor vehicle seat with integrated safety belt

Abstract

The invention relates to a seat (10) for a motor vehicle, comprising a seat frame (200), a backrest frame (300) and a seat belt reel (401) fixed to the backrest frame. According to the invention: - the seat comprises a supporting structure (100) equipped with means (111A) for fixing to a floor of the motor vehicle, and - the seat frame and the backrest frame are mounted independently on the supporting structure. Figure for abstract: Fig.1

Description

Title of the invention: Motor vehicle seat with integrated safety belt Technical field of the invention

[0001] The present invention relates generally to the habitability of motor vehicles.

[0002] It relates more particularly to a seat for a motor vehicle, comprising a seat frame, a backrest frame and a seat belt reel fixed to the backrest frame.

[0003] It also relates to a motor vehicle comprising a floor and at least one seat as mentioned above, secured to the floor. State of the art

[0004] In the automotive field, the front seats are generally mounted on the floor so that they can be moved forward or backward, at the convenience of the occupant (mainly taking into account their morphology).

[0005] Such a seat comprises a seat, a backrest and movable rails which are slidably mounted in rails fixed to the floor. The conventional architecture consists of mounting the backrest on the seat, and the seat on the movable rails.

[0006] Generally, the seat belt system is mounted, not on the seat, but on the vehicle itself. Thus, it is usually provided: - a fixed anchor point at one end of the belt, located on the floor, on one side of the seat, - a seat belt reel located on the same first side of the seat, on a frame upright, at the height of the seat headrest, and - an unlockable anchor point that can accommodate a seat belt buckle, located on the floor, on the other side of the seat.

[0007] This arrangement complicates the design and assembly of the vehicle, as well as its driving pleasure. Indeed, if it were mounted on the seat back, the seat belt reel would always be perfectly positioned, regardless of the forward or backward position of the seat on the floor and the inclination of the backrest relative to the seat.

[0008] Therefore, it would be preferred that the entire seat belt system be mounted on the seat.

[0009] But to mount it there, the seat frame would have to be greatly stiffened. Indeed, when the seat belt reel is fixed at the top of the backrest and the bottom of the backrest is articulated on the seat, the lever arm between the reel and this articulation is important. Therefore, in the event of a frontal impact, the reel will exert strong stress not only on the backrest, but also on the seat at the articulation, and consequently also on the rails.

[0010] The disadvantage is that, in order to withstand these constraints, the seat must be particularly rigid, and therefore heavy and expensive.

[0011] This is why seats equipped with their own seat belt systems are rare and reserved for high-end vehicles. Presentation of the invention

[0012] In order to overcome the aforementioned drawback of the state of the art, the present invention proposes to use a different seat architecture and to equip it with a seat belt system.

[0013] More particularly, according to the invention there is provided a seat as defined in the introduction, in which: - the seat comprises a supporting structure equipped with means of attachment to a floor of the motor vehicle, and in which - the seat frame and the backrest frame are mounted independently on the supporting structure, the backrest frame being mounted movably on the supporting structure.

[0014] The invention thus proposes to place the seat belt reel on a particular seat in the sense that it has an architecture in which the seat and the backrest are each mounted movably, independently, on a supporting structure. Such an architecture makes it possible to decouple the movements of the backrest and the seat. This is why we speak of “decoupled architecture”.

[0015] Thanks to this architecture, the stresses exerted in the event of a frontal impact on the reel, at the top of the backrest, are not transmitted to the seat but are directly transmitted to the supporting structure (in particular to the slides fixed to the floor). Therefore, the seat used does not have to be reinforced, to the benefit of its weight and its manufacturing cost. This seat can even be the same as that used in more conventional seats (i.e. without a seat belt reel), which avoids a duplication of part references, to the benefit of the manufacturing and storage costs of these parts.

[0016] Other advantageous and non-limiting characteristics of the seat according to the invention, taken individually or in all technically possible combinations, are the following: - the seat frame is movably mounted on the supporting structure; - a fixed anchoring system is provided for one end of the seat belt strap, which is fixed to the supporting structure; - a locking system for a seat belt buckle is provided, which is fixed to the supporting structure; - said reel is located closer to one side of the seat than to the other; - the backrest frame comprises a frame of which two opposite sides form two lateral flanks, the lateral flank located on the first side of the seat being more rigid than the other lateral flank; - the supporting structure comprises two slides which each comprise a fixed rail equipped with means for fixing to the floor of the motor vehicle, and a movable rail which is slidably mounted in the fixed rail and which carries a support to which the backrest frame is coupled, the support of the movable rail located on the first side of the seat being more rigid than the support of the other movable rail; - the backrest frame comprises a frame, with two side flanks, as well as an upper cross member and a lower cross member which extend between the two side flanks, the backrest frame being adapted to tilt relative to the supporting structure around a pivot axis located above a plane which is parallel to the floor and which passes through the highest point of the seat frame regardless of the position of the seat frame relative to the floor; - as a variant, the backrest frame being adapted to tilt relative to the supporting structure around a pivot axis located below a plane which is parallel to the floor and which passes through the highest point of the seat frame regardless of the position of the seat frame relative to the floor; - preferably, this plane passes through the lowest point of the seat frame when the latter is in the high position; - the backrest frame comprises two connecting sides each having one end fixed to the frame and one end mounted to move on the supporting structure around said pivot axis; - at least one jack is provided, one part of which is coupled to the supporting structure and another part of which is coupled to the connecting flank, at a distance from said pivot axis.

[0017] The invention also provides a motor vehicle comprising a floor and a seat as mentioned above, the supporting structure of which is fixed to the floor.

[0018] Of course, the various features, variants and embodiments of the invention may be combined with each other in various combinations to the extent that they are not incompatible or mutually exclusive. Detailed description of the invention

[0019] The description which follows with reference to the appended drawings, given as non-limiting examples, will make it clear what the invention consists of and how it can be implemented.

[0020] In the attached drawings:

[0021] [Fig-1] is a schematic perspective view of part of a seat conforming to a first embodiment of the invention;

[0022] [Fig.2] is a schematic perspective view of a part of a seat according to a second embodiment of the invention.

[0023] In Figures 1 and 2, two embodiments of a frame of a seat 10 are shown, intended to be installed in the passenger compartment of a motor vehicle (car, bus, truck, boat, airplane, etc.) and to be fixed to the floor of this motor vehicle.

[0024] In the remainder of the description, the terms "front" and "rear" will be used in relation to the motor vehicle (which will be considered to be on a horizontal road), the front part of an element designating the part of this element which is located on the side of the hood of the vehicle and the rear part designating the part of this element which is located on the opposite side.

[0025] The terms "lower" (or "bottom") and "upper" (or "top") will be used in the same way, the lower part of an element designating the part of this element which is located on the side of the floor of the vehicle and the upper part designating the part of this element which is located on the side of the roof of the vehicle.

[0026] The adjective "longitudinal" will apply to a direction or axis oriented from the front to the rear of the vehicle, parallel to the direction of travel of the vehicle when the steering wheel is in the neutral position.

[0027] The adjective “transverse” will apply to a direction or axis oriented horizontally and orthogonally to the longitudinal axes.

[0028] The term “fixed” will be used to designate a rigid blocking (without mobility) between two elements.

[0029] The term “coupled” will be used to designate a connection between two elements with any number of degrees of freedom, including zero.

[0030] The expression “movably mounted” will be used to designate a connection between two elements with a number of degrees of freedom at least equal to one.

[0031] The concept of "rigidity" will be used in the following to compare the mechanical strength of similar components of the seat frame. Typically, a component will be said to be more rigid than another if, when subjected to the same stress under identical conditions, it deforms less. This rigidity can be obtained in various ways, for example by increasing the dimensions of one component compared to another, by equipping it with stiffening ribs, by manufacturing it in a material having a higher Young's modulus, etc.

[0032] As shown in the figures, the seat 10 conventionally comprises a seat and a backrest, each comprising a frame and a padding attached to the frame. In the figures, only the seat 200 and backrest 300 frames are shown.

[0033] It also comprises a supporting structure 100 on which the seat 200 and backrest 300 frames are directly mounted. By “directly”, it is meant that the backrest frame 300 is not mounted on the seat frame, but is independent of the latter. Thus, a movement of the seat frame 200 does not cause a movement of the backrest frame 300 (and vice versa).

[0034] This supporting structure 100 and these seat 200 and back 300 frames are here all made of metal material.

[0035] The seat 10 is designed to be mounted so as to be mobile in translation on the floor of the motor vehicle. Its supporting structure comprises two longitudinal slides 110 for this purpose.

[0036] Each slide 110 comprises, on the one hand, a lower fixed rail 111 which is equipped with means 11 IA for fixing to the floor of the vehicle, and, on the other hand, an upper movable rail 112 mounted to slide in the fixed rail 111 and to which the seat 200 and backrest 300 frames are coupled.

[0037] Each fixed rail 111 has, for example, a U-shaped cross-section, with a base and two wings.

[0038] The fixing means 111A of the fixed rails 111 are here in the form of plates welded under the bases of the fixed rails 111 and having openings for the passage of screws for fixing the fixed rails 111 to the floor of the vehicle.

[0039] Each movable rail 112 has, for example, a cross-section in the shape of a ji, with an upper wall and two wings engaged between the wings of the corresponding fixed rail 111.

[0040] The two slides 110 are located parallel to each other and therefore offer the seat 10 longitudinal sliding mobility, in translation.

[0041] Conventionally, means are provided for locking (not visible in the figures) the sliding of these rails to lock the seat in longitudinal position on the floor, and an unlocking lever 101 for these locking means to release this sliding if necessary.

[0042] Here, the supporting structure 100 further comprises two supports 113, 114 respectively fixed to the movable rails 112 and to which the seat 200 and backrest 300 frames are more precisely coupled.

[0043] These supports 113, 114 are in the form of ribs or plates which rise vertically projecting from the upper walls of the movable rails 112 and which extend longitudinally. Here, they extend over the entire length of the movable rails 112 and are fixed thereto, for example by screwing or welding.

[0044] At this stage, it is possible to briefly describe how the seat frame 200 is mounted on the supporting structure 100.

[0045] The seat frame 200 has a frame shape with two lateral flanks 201 connected together at the front and at the rear by two crosspieces 202.

[0046] This seat frame 200 could be fixed to the supporting structure, without any mobility. However, preferably, it is mounted on the latter in a mobile manner.

[0047] For this, it is mounted on the supporting structure 100 by a system of four connecting rods 250 (only one of which is visible in the figures), including two identical rear connecting rods and two substantially identical front connecting rods.

[0048] The connecting rods are distributed on both sides of the seat frame. They are each articulated, on one side, on the supports 113, 114 of the movable rails 112, and on the other, on one of the lateral flanks 201 of the seat frame 200. By “articulated”, it is meant that a simple pivot type connection is provided between these two components. These pivot connections have articulation axes which are transverse.

[0049] In practice, these connecting rods are arranged so as to be able to switch between two extreme positions, including a substantially vertical position allowing the seat to be placed in a high position, and a substantially horizontal position allowing the seat to be placed in a low position.

[0050] In the high position, the seat is located further back in relation to the backrest than in the low position (it therefore moves forward when it lowers). In this way, a tall person who lowers the seat would benefit from more surface area to sit on than a short person who raises the seat. Indeed, when raising, a rear part of the seat retracts under and behind the backrest.

[0051] Operating means 500 are provided for controlling the raising or lowering of the seat. These operating means 500 are preferably manual, but they could alternatively be motorized.

[0052] Here they comprise a lever (not visible) adapted to pivot around a transverse axis. This lever is coupled to a pumping system which makes it possible to force one of the connecting rods to pivot in one direction or the other to raise or lower the seat.

[0053] As further shown in [Fig. 1], the backrest frame 300 extends mainly above the seat frame 200.

[0054] In practice, it comprises here a substantially rectangular frame 301, with two lateral sides 303 whose ends are connected by upper 304 and lower 305 crosspieces. This frame 301 is entirely located above the seat frame 200, whatever the position of the latter.

[0055] The seat 10 also has a safety belt device, only part of which is shown in Figures 1 and 2.

[0056] This seat belt device here has three anchor points.

[0057] It firstly comprises a safety belt onto which a buckle is threaded (not shown).

[0058] It also comprises, on a first side of the seat, an anchoring system 403 for one end of the seat belt. This anchoring system 403 comprises, for example, an opening provided in the support 113, through which a bolt is screwed for fixing this end of the seat belt.

[0059] It also comprises, on the other side of the seat, a locking system 402 for the seat belt buckle. This locking system comprises, for example, an opening provided in the support 114, through which a bolt is screwed for fixing a tulip for receiving the buckle.

[0060] Finally, it comprises, on the first side of the seat, a seat belt reel 401. This reel 401 comprises a frame which houses means for winding and locking the seat belt in the event of an impact. This frame is here fixed to the frame 301 of the backrest frame 300, for example by screws.

[0061] It is more precisely fixed to the upper corner of this frame 301, on the first side of the seat, at the junction between the upper crosspiece 304 and one of the lateral flanks 303.

[0062] As introduced above, in Figures 1 and 2, two embodiments of the seat 10 are shown, which differ in their mounting of the frame of the backrest 300 on the supporting structure 100.

[0063] In the first embodiment illustrated in [Fig.l], the backrest is articulated on the supporting structure 100 around a pivot axis A1 located above the seat when the latter is in the high position.

[0064] For this, the supports 113, 114 are located on either side of the seat structure 200 and they each have a rear part which rises above the seat.

[0065] The frame 301 of the backrest frame 300 is then articulated on these rear parts of the supports 113, 114 so that the pivot axis A1 is located above the seat regardless of the height of the latter relative to the floor, and that it does not hinder the tilting of the backrest. More precisely here, the pivot axis A1 is located at the height of the lower crosspiece 305 of the frame 301 of the backrest frame 300.

[0066] Operating means are provided allowing the occupant of the seat 10 to adjust the inclination of the backrest around the pivot axis A1.

[0067] These means of maneuver could take various forms.

[0068] Thus, as shown in [Fig.l], it could be a question of manual maneuvering means.

[0069] They could typically be of the inactive type and include a lever adapted to unlock the pivoting mobility of the backrest, the occupant then having to manually adjust the inclination of the backrest before releasing the lever to lock this mobility.

[0070] They could otherwise be of the active type and include: - either a wheel accessible on the side of the seat and allowing, when it turns, to tilt the backrest around the pivot axis Al, - either a lever equipped with a pumping module, the lever allowing, when actuated, to tilt the backrest around the pivot axis Al.

[0071] In all cases, to compensate for the weight of the backrest, it is preferable to provide means for returning the backrest forward.

[0072] Alternatively, the maneuvering means could be motorized.

[0073] In the second embodiment illustrated in [Fig.2], the backrest is hinged on the supporting structure 100 around a pivot axis Al located below the seat when the latter is in the high position.

[0074] The backrest frame 300 comprises for this purpose, in addition to the frame 301, two joining flanks 302 which extend in the extension of the lateral flanks 303 of the frame 301, downwards, on either side of the seat frame 200.

[0075] These two joining sides 302 are formed in a single piece with the frame 301 or are fixed to it.

[0076] They are in the form of plates and extend in length parallel to each other, from the frame 301 to a free end. Here they are curved forward, so that their free ends point forward.

[0077] They are mounted movably on the supports 113, 114. They are more precisely articulated on these supports so that the backrest can tilt forwards or backwards around the pivot axis Al. In practice, this pivot axis Al then extends only a few centimeters above the movable rails 112.

[0078] Here again, operating means are provided allowing the occupant of the seat 10 to adjust the inclination of the backrest around the pivot axis A1.

[0079] These means of maneuver could take various forms.

[0080] Thus, it could be manual operating means such as those described above.

[0081] However, in this embodiment, it will be preferred to use a motorized control of the backrest tilt.

[0082] For this, the backrest frame 300 is mounted freely rotatable on the supporting structure 100 around the pivot axis A1.

[0083] Furthermore, as shown in [Fig.2], the operating means comprise a jack 330 comprising a first part articulated on the support 113, 114 around a first transverse axis A2, and a second part articulated on the joining flange 302, around a second transverse axis A3, these two parts being able to slide relative to each other.

[0084] In practice, the cylinder used could be pneumatic or hydraulic (the first part forming for example a sheath and the second part forming a rod mounted sliding in the sheath). But it will preferably be an electric jack comprising a worm screw system (the first part comprising, for example, a motor with a threaded output shaft, and the second part comprising a nut screwed onto the output shaft).

[0085] The first and second transverse axes A2, A3 are located at a distance from the pivot axis A1. Thus, the first transverse axis A2 is located further back from the support 113, 114 than the pivot axis A1, and the second transverse axis A3 is located mid-length of the junction flange 302.

[0086] In this way, in the event of a frontal impact, the backrest is retained on the supporting structure at three axes A1, A2, A3, which form a triangle allowing the forces to be better distributed. Typically, the stresses on each support 113, 114 will not be exerted at a single point (as is the case in [Fig.l]), but at several points distant from each other. In this way, both the supporting structure 100 and the backrest frame 300 can be dimensioned as precisely as possible, which will make it possible to lighten the seat 10.

[0087] In these two embodiments, provision is made to stiffen the backrest frame 300 and the supporting structure 100 taking into account the presence of the seat belt reel 401. The latter is in fact located at a distance from the pivot axis A1, which forms a significant lever arm when the vehicle suffers a frontal impact and the occupant of the seat is restrained by the seat belt device.

[0088] In the two embodiments illustrated in the figures, during such an impact, the stresses exerted on the reel 401 are transmitted to the backrest then to the supporting structure 100 and to the floor of the vehicle, but they are not transmitted to the seat, the latter therefore not having to be sized accordingly.

[0089] Preferably, the two lateral flanks 303, 304 of the frame 301 of the backrest frame 300 have different rigidities, the lateral flank 303 located on the first side (the side where the reel is located) being dimensioned to be more rigid than the other lateral flank. For this purpose, it may extend over a greater width than the latter. In addition or as a variant, it may have a thickness greater than the latter. In addition or as a variant, it may include more reinforcing structures. In addition or as a variant, it may be made of a less elastic material than that used to make the other lateral flank.

[0090] The idea is in fact to dimension the various components of the seat 10 as precisely as possible. It is in fact not necessary for the two lateral flanks 303, 304 of the frame 301 to have identical rigidities since the stresses exerted by the winder 401 will not be distributed symmetrically in these two lateral flanks 303, 304. Dimensioning these components differently then makes it possible to restrict the total weight of the seat 10 and to reduce its manufacturing cost.

[0091] In the same way and for the same purpose, the support 113 provided on the movable rail 112 located on the first side of the seat 10 is made so as to be more rigid than the other support 114.

[0092] In the same way again, in the second embodiment illustrated in [Fig.2], the junction flank 302 located on the first side of the seat 10 is more rigid than the other.

[0093] Finally, it will be noted that, since adjusting the height of the seat relative to the floor makes it possible to adjust the height of the seat relative to the backrest over a travel greater than 50 mm (here approximately 60 mm), it can be provided that the backrest has a headrest function (the upper crosspiece of the frame 301 forming the frame of the headrest). Indeed, in the two embodiments illustrated, no adjustment of the height of the headrest relative to the backrest will be necessary.

[0094] The present invention is in no way limited to the embodiments described and shown, but those skilled in the art will be able to provide any variant in accordance with the invention.

[0095] Typically, it could be provided that the anchoring system (403) or the locking system (402) of the seat belt device is fixed not on the seat, but rather on the floor of the vehicle.

[0096] According to another variant, it could be provided to use a jack (330) only, on the first side of the seat.

Claims

Claims

1. Seat (10) for a motor vehicle, comprising a seat frame (200), a backrest frame (300) and a seat belt reel (401) fixed to the backrest frame (300) closer to a first side of the seat (10) than to the other, characterized in that: - the seat (10) comprises a supporting structure (100) equipped with means (11 IA) for fixing to a floor of the motor vehicle, the supporting structure (100) comprising two slides (110) which each comprise a fixed rail (111) equipped with means (111 A) for fixing to the floor of the motor vehicle, and a movable rail (112) which is slidably mounted in the fixed rail (111) and which carries a support (113, 114) to which the backrest frame (300) is coupled, and in that - the support (113) of the movable rail (112) located on the first side of the seat (10) is more rigid than the support (113) of the other movable rail (112),- the seat frame (200) and the backrest frame (300) are mounted independently on the supporting structure (100), the backrest frame (300) being mounted movably on the supporting structure (100).,

2. A seat (10) according to claim 1, wherein the seat frame (200) is movably mounted on the supporting structure (100).

3. Seat (10) according to claim 1 or 2, wherein there is provided: - a fixed anchoring system (403) for a seat belt strap end, which is fixed to the supporting structure (100), and / or - a locking system (402) of a seat belt buckle, which is fixed to the supporting structure (100).

4. Seat (10) according to one of claims 1 to 3, wherein, said winder (401) being located closer to a first side of the seat (10) than to the other, the backrest frame (300) comprises a frame (301) of which two opposite sides form two lateral flanks (303, 304), the lateral flank (303) located on the first side of the seat (10) being more rigid than the other lateral flank (304).

5. Seat (10) according to one of claims 1 to 4, in which the backrest frame (300) comprises a frame (301), with two lateral flanks (303, 304), as well as an upper crossbar (304) and a lower crossbar (305) which extend between the two flanks lateral (303, 304), the backrest frame (300) being adapted to tilt relative to the supporting structure (100) around a pivot axis (Al) located above a plane which is parallel to the floor and which passes through the highest point of the seat frame (200) regardless of the position of the seat frame (200) relative to the floor.

6. Seat (10) according to one of claims 1 to 4, wherein the backrest frame (300) comprises a frame (301), with two lateral flanks (303, 304), as well as an upper cross member (304) and a lower cross member (305) which extend between the two lateral flanks (303, 304), the backrest frame (300) being adapted to tilt relative to the supporting structure (100) around a pivot axis (A1) located below a plane which is parallel to the floor and which passes through the highest point of the seat frame (200) regardless of the position of the seat frame (200) relative to the floor.

7. Seat (10) according to claim 6, in which the backrest frame (300) comprises two connecting flanks (302) each having one end fixed to the frame (301) and one end mounted to move on the supporting structure (100) around said pivot axis (Al).

8. Seat (10) according to claim 7, in which at least one jack is provided, one part of which is coupled to the supporting structure (100) and another part of which is coupled to the connecting flank (302), at a distance from said pivot axis (Al).

9. Motor vehicle comprising a floor, characterized in that it comprises at least one seat (10) according to one of claims 1 to 8, the supporting structure (100) of which is fixed to the floor.

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