Reclining backrest car seat

Abstract

The invention relates to a seat (10) for a motor vehicle, comprising: - a load-bearing structure (100) equipped with means for attaching it to the floor of the motor vehicle, - a seat comprising a seat frame (200) which is movably mounted vertically on the load-bearing structure between a high and a low position, and - a backrest frame (300) mounted on the load-bearing structure so as to be able to pivot about a pivot axis (A1). According to the invention, the pivot axis is located under a plane: - which is parallel to the floor, and - which passes through the highest point of the seat frame when the seat frame is in the high position. Figure for the abstract: Fig. 1

Description

Title of the invention: Motor vehicle seat with tilting backrest 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 supporting structure equipped with means of fixing to a floor of the motor vehicle, - a seat comprising a seat frame which is mounted to move in height on the supporting structure between a high position and a low position, and - a backrest frame mounted on the supporting structure so as to be able to tilt around a pivot axis, said seat frame and said backrest frame being movable relative to the supporting structure independently of each other.

[0003] It also relates to a motor vehicle comprising a floor and at least one seat as mentioned above, the supporting structure of which is fixed 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 mounted to slide in rails fixed to the floor.

[0006] A conventional architecture consists of mounting the backrest on the seat, and the seat on the movable rails.

[0007] A second architecture, which has fallen somewhat into disuse, consists of mounting the seat and backrest on a supporting structure comprising the movable rails. Such an architecture makes it possible to decouple the movements of the backrest and the seat. This is why we speak of “decoupled architecture”.

[0008] The seat is generally coupled to the supporting structure by connecting rods allowing this seat to rise and fall. In this way the occupant can adjust his seat height in the vehicle.

[0009] In the same way, the backrest is generally coupled to the supporting structure by a joint allowing its inclination to be adjusted.

[0010] More specifically, the backrest frame generally forms a frame located above and behind the seat. The supporting structure comprises connecting sides which rise from the movable rails and which extend on either side of the seat. The joint allowing the inclination of the backrest to be adjusted in relation to the supporting structure is then located at the junction between the backrest frame and the connecting sides, so that the pivot axis of the backrest is located substantially above the seat.

[0011] Such a seat is designed to accommodate occupants with very varied body shapes, and in particular people of sizes ranging for example from 1.50 m to 2.10 m.

[0012] It then turns out that the decoupled architecture does not allow for a seat to be provided that is comfortable regardless of the size of the occupant. Indeed, a tall occupant will generally want to lower the seat to keep their head away from the roof of the vehicle. This will not pose a problem as long as the backrest is kept in line with the connecting sides. But this will no longer be the case when the occupant wishes to tilt their backrest further back.

[0013] By doing this, since the seat is located well below the pivot axis of the backrest, a discontinuity will appear between the backrest and the connecting sides, which discontinuity will form a sort of step which will be unpleasant for the occupant and which will force the latter to move forward on his seat. Also, the occupant will not benefit from the entire support surface of the seat and only an upper part of his back will rest on the backrest.

[0014] Currently, the first architecture (in which the backrest is mounted on the seat) is therefore preferred to this decoupled architecture. Presentation of the invention

[0015] In order to overcome the aforementioned drawbacks of the state of the art, the present invention proposes to use the decoupled architecture but to review the kinematics of the backrest so that the seat is pleasant for the occupant regardless of the latter's size.

[0016] More particularly, the invention provides a seat as defined in the introduction, in which the pivot axis of the backrest is located under a geometric plane - which is parallel to the floor, and - which passes through the highest point of the seat frame when the seat frame is in the high position.

[0017] The idea of ​​the invention compared to the prior art is to move the pivot axis of the backrest downwards, below the articulation axis of the reeds of the occupant of the seat.

[0018] Thus, when the backrest tilts, it is the entire support area of ​​the user's back that tilts and not just part of this area. There is then no discontinuity of support for the user's back.

[0019] It will further be noted that thanks to the invention, if the pivot axis is located under the seat, The further the occupant tilts the backrest, the more space they will have on the seat to sit on, which will be advantageous for taller people.

[0020] Furthermore, tilting the backrest around a low axis prevents the occupant of the seat from sliding too much and having to sit up straight in the seat when the backrest tilts.

[0021] 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 comprising a structural seating surface for a passenger, the pivot axis is located under a plane which is parallel to the floor and which passes through the lowest point of the structural seating surface when the seat frame is in the high position; - the seat frame comprising two side plates, the pivot axis is located under a plane which is parallel to the floor and which passes through the lowest point of the front ends of said side plates when the seat frame is in the high position; - the backrest frame comprises a frame and 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; - said pivot axis is located at the front of a mid-plane of the frame; - manual operating means are provided allowing an occupant of the seat to pivot the backrest frame relative to the supporting structure around the pivot axis; - motorized operating means are provided for pivoting the backrest frame relative to the supporting structure around the pivot axis; - said motorized operating means comprising a jack, one part of which is coupled to the supporting structure, at a distance from the pivot axis, and another part of which is coupled to the backrest frame, at a distance from the pivot axis; - the seat frame is mounted on the supporting structure by four connecting rods distributed in pairs on each side of the seat frame, each connecting rod being articulated, on one side, on the seat frame, and, on the other, on the supporting structure; - the supporting structure comprises two slides, each of which comprises 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 on which the backrest frame is mounted.

[0022] The invention also provides a motor vehicle comprising a floor and at least one seat as mentioned above, the supporting structure of which is fixed to the floor.

[0023] 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

[0024] 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.

[0025] In the attached drawings:

[0026] [Fig-1] is a schematic perspective view of part of a seat conforming to the invention, shown with its backrest frame in neutral position;

[0027] [Fig.2] is a schematic side view of an alternative embodiment of the seat illustrated in [Fig.l], in which the backrest frame is shown in the neutral position;

[0028] [Fig.3] is a view corresponding to that of [Fig.2], in which the frame of backrest is shown in a backward tilted position.

[0029] In [Fig.l], there is shown a part of a seat 10 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.

[0030] 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.

[0031] 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.

[0032] 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.

[0033] The adjective “transverse” will apply to a direction or axis oriented horizontally and orthogonally to the longitudinal axes.

[0034] The term “fixed” will be used to designate a rigid blocking (without mobility) between two elements.

[0035] The term “coupled” will be used to designate a connection between two elements with any number of degrees of freedom, including zero.

[0036] 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.

[0037] 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 frames 200 seat and 300 backrest are shown. They are metallic here.

[0038] The seat 10 also comprises a supporting structure 100 on which the seat 200 and back 300 frames are directly mounted. By “directly”, it is meant that the back frame 300 is not mounted on the seat frame, but is independent of it. Thus, a movement of the seat frame 200 does not cause a movement of the back frame 300 (and vice versa).

[0039] The seat 10 is preferably designed to be mounted so as to be able to move in translation on the floor of the motor vehicle. Its supporting structure comprises for this purpose two longitudinal slides 110, which can be briefly described.

[0040] Each slide 110 comprises, on the one hand, a lower fixed rail 111 which is equipped with means 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.

[0041] Each fixed rail 111 has a cross-section, for example U-shaped, with a base and two wings.

[0042] As shown in Figures 2 and 3, the means for fixing the fixed rail 111 to the floor then take the form of openings (not visible) made in the base of the U and allowing the passage of fixing screws 21 of the fixed rail 111 on the floor 20 of the vehicle.

[0043] Each movable rail 112 has a cross-section for example in the shape of a ji, with an upper wall and two wings engaged between the wings of the corresponding fixed rail 111.

[0044] It is noted in [Fig. 1] that each movable rail 112 is equipped with a support 113 making it easier to couple components to this movable rail 112. In practice, each support 113 is in the form of a longitudinally elongated metal wall which rises above the upper wall of the movable rail 112. Each support 113 can for example be screwed or welded to the movable rail 112.

[0045] The two slides 110 are located parallel to each other and therefore offer the seat 10 longitudinal sliding mobility, in translation.

[0046] 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.

[0047] The seat frame 200 and the manner in which it is mounted on the supporting structure 100 can also be briefly described.

[0048] This seat frame 200 is mounted on the supporting structure 100 in a manner that can move in height.

[0049] For this, the seat frame 200 here has a frame shape with two sides lateral 201 (also called “side plates”) connected together at the front and rear by crosspieces 202. Alternatively, it could be formed by a plastic cradle.

[0050] It also comprises a structural seating surface which is covered by the seat upholstery and on which the passenger can sit. In practice, this structural seating surface is formed by the upper surface of a structural sheet extending between the two lateral flanks 201. This sheet can typically be formed of intersecting metal wires.

[0051] Alternatively, the seat frame may comprise a bucket, for example made of plastic, covered by the upholstery, in which case the structural seat surface will be formed by the upper surface of this bucket.

[0052] This seat frame 200 is mounted on the supporting structure 100 by a system of four connecting rods, including two identical rear connecting rods and two substantially identical front connecting rods.

[0053] The connecting rods are distributed on both sides of the seat frame. They are each articulated, on one side, on one of the movable rails 112 (and more precisely on the supports 113 fixed to these rails), and on the other, to one of the sides 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.

[0054] 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 the extreme high position, and a substantially horizontal position allowing the seat to be placed in the extreme low position.

[0055] In the extreme high position, the seat is located further back relative to the backrest than in the extreme low position. 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.

[0056] 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.

[0057] Here they comprise a lever (not visible) associated with a pumping system making it possible to force the connecting rods to pivot in one direction or the other.

[0058] As [Fig.l] also shows, the backrest frame 300 extends above and on either side of the seat frame 200.

[0059] 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 located above the seat frame 200.

[0060] The backrest frame 300 further comprises 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.

[0061] These two joining sides 302 are formed in a single piece with the frame 301 or are fixed to it.

[0062] They have plate shapes and extend lengthwise parallel to each other, from the frame 301 to a free end. Here they are curved forward, so that their free ends point forward.

[0063] It is by these joining flanks 302 that the backrest frame 300 is mounted movably on the supports 113. In other words, the backrest frame 300 is articulated on these supports 113 at the level of these joining flanks 302, so that the backrest can tilt forwards and backwards, around a pivot axis A1.

[0064] The position of this pivot axis Al is chosen with care.

[0065] As shown in [Fig.2], this pivot axis A1 is positioned under a plane P2 which is parallel to the floor (and therefore to the sliding axes of the slides) and which passes through the articulation axis of the reeds of an occupant of average size.

[0066] This plane P2 is located approximately eight centimeters above the average plane of the upper face of the seat upholstery. In other words, if we consider the area of ​​the seat upholstery on which an occupant is normally likely to sit, we can define a plane parallel to the floor and which passes as close as possible to this area (for example in the sense of the least squares method). Then, the plane P2 is located twelve centimeters above this plane.

[0067] The idea is that the pivot axis A1 of the backrest is located below the articulation axis of the occupant's reeds. If this were not the case, when the backrest tilts from its neutral position shown in [Fig.2] to its maximum reclining position shown in [Fig.3], a step would form at the bottom of the backrest, which would be unpleasant for the back of the occupant of the seat.

[0068] Here, the pivot axis A1 is positioned substantially lower, preferably at the height of the seat or below it. It is thus preferably positioned below the plane which is parallel to the plane P2 and which passes through the lowest point of the structural seat surface (when the seat is in the high position). Here, it is positioned below the plane which is parallel to the plane P2 and which passes through the lowest point of the front ends of the two lateral flanges 201 (when the seat frame 200 is in the high position).

[0069] As shown in the figures, it is here positioned under the seat frame 200 when the latter is in the high position. In this way, it is the entire backrest upholstery that tilts when the occupant wants to pivot the backrest. Consequently, the backrest never forms a step for the back of the occupant of the seat. 10.

[0070] We can also define the average plane PI of the frame 301 of the backrest frame 300 as the plane which passes through the lateral flanks 303 of this frame and which is located on average at mid-thickness of these flanks.

[0071] The pivot axis A1 is furthermore located at the front of this average plane P1. Thus, when it tilts the backrest, the sliding of the occupant in his seat remains restricted.

[0072] Operating means are provided allowing the occupant of the seat 10 to adjust the inclination of the backrest around the pivot axis A1.

[0073] These means of maneuver could take various forms.

[0074] Thus, as shown in [Fig.l], it could be a question of manual maneuvering means.

[0075] They could typically be of the inactive type (also called discontinuous 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.

[0076] They could otherwise be of the active type (also called continuous 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 A1, - either a lever equipped with a pumping module, the lever allowing, when actuated, to tilt the backrest around the pivot axis Al.

[0077] In all cases, to compensate for the weight of the backrest, it is preferable to provide means for returning the backrest forward.

[0078] In all cases also, the tilting of the backrest will be implemented by means of two articulations provided on either side of the seat, on the pivot axis A1. These two articulations must be synchronized to allow the tilting of the backrest.

[0079] In the case where the joints are of the discontinuous type, a system of hoses and cables will allow the synchronization of the locking and unlocking of the two joints.

[0080] In the case where the joints are of the continuous type, it will not be possible to use a transverse bar fixed between the two joints, due to the seat which must be able to rise and fall in the space located between these joints. This bar will instead have to be offset downwards, at the level of the slides 110, and associated with a pinion mechanism to be coupled to the joints. This solution will unfortunately be complex and heavy, so it will not be preferred.

[0081] Alternatively, the maneuvering means may be motorized.

[0082] Thus, as shown in Figures 2 and 3, they can include a jack 330 comprising a first part articulated on the support 113 around a first transverse axis A2, and a second part articulated to the junction flange 302, around a second transverse axis A3, these two parts being able to slide relative to each other. The backrest frame 300 is then mounted on the supporting structure 100 by a simple pivot connection, with a pivot axis A1.

[0083] In practice, the cylinder used could be pneumatic or hydraulic (the first part forming for example a sleeve and the second part forming a rod mounted sliding in the sleeve). But it will preferably be an electric cylinder. This electric cylinder could comprise a worm screw system (the first part comprising for example a motor whose output shaft is threaded, and the second part comprising a nut screwed onto the output shaft). Alternatively, it could comprise a rack and pinion system (the first part comprising for example a pinion coupled to a motor fixed to the support 113, and the second part comprising a rack coupled to the connecting flange 302).

[0084] The first and second transverse axes A2, A3 are located at a distance from the pivot axis AL. Thus, the first transverse axis A2 is located further back from the support 113 than the pivot axis Al, and the second transverse axis A3 is located mid-length of the junction flange 302.

[0085] 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 the support 113 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.

[0086] 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, no adjustment of the height of the headrest relative to the backrest will be necessary.

[0087] It will also be noted that the corner located at the junction between the upper crosspiece and one of the lateral flanks of the frame 301 forms a notch serving as a passage for the seat belt. Here, since the backrest frame 300 is directly fixed to the movable rails 112, the stresses exerted by the seat belt on the backrest during a road accident are not transmitted to the seat, which therefore does not have to be reinforced accordingly.

[0088] The present invention is in no way limited to the embodiment described and re presented, but those skilled in the art will be able to make any variation in accordance with the invention.

[0089] Typically, it could be provided that the supports which extend above the movable rails rise higher than in the figures, so that the pivot axis is located at the height of the seat frame or even slightly above it.

[0090] It would also have been possible to move the pivot axis forward or backward on the supports, depending on the desired kinematics.

Claims

Claims

1. Seat (10) for a motor vehicle, comprising: - a supporting structure (100) equipped with means (11 IA) for fixing to a floor (20) of the motor vehicle, - a seat comprising a seat frame (200) which is mounted so as to be movable in height on the supporting structure (100) between a high position and a low position, and - a backrest frame (300) mounted on the supporting structure (100) so as to be able to tilt around a pivot axis (Al), said seat frame (200) and said backrest frame (300) being movable relative to the supporting structure (100) independently of each other, characterized in that the pivot axis (Al) is located under a plane: - which is parallel to the floor (20), and - which passes through the highest point of the seat frame (200) when the seat frame (200) is in high position.

2. Seat (10) according to claim 1, wherein, the seat frame (200) comprising a structural seating surface for a passenger, the pivot axis (Al) is located under a plane which is parallel to the floor (20) and which passes through the lowest point of the structural seating surface when the seat frame (200) is in the high position.

3. Seat (10) according to claim 1 or 2, in which, the seat frame (200) comprising two lateral flanges (201), the pivot axis (Al) is located under a plane which is parallel to the floor (20) and which passes through the lowest point of the front ends of said lateral flanges (201) when the seat frame (200) is in the high position.

4. Seat (10) according to one of claims 1 to 3, in which the backrest frame (300) comprises a frame (301) and two connecting flanks (302) each having one end fixed to the frame (301) and one end mounted movably on the supporting structure (100) around said pivot axis (Al).

5. Seat (10) according to claim 4, wherein said pivot axis (Al) is located in front of a mid-plane (PI) of the frame (301).

6. Seat (10) according to one of claims 1 to 5, in which manual operating means are provided allowing an occupant of the seat (10) to pivot the backrest frame (300) relative to the supporting structure (100) around the pivot axis (Al).

7. Seat (10) according to one of claims 1 to 5, in which motorized operating means are provided for pivoting the backrest frame (300) relative to the supporting structure (100) around the pivot axis (A1), said motorized operating means comprising a jack of which one part (601) is coupled to the supporting structure (100), at a distance from the pivot axis, and of which another part (602) is coupled to the backrest frame (300), at a distance from the pivot axis.

8. Seat (10) according to one of claims 1 to 7, in which the seat frame (200) is mounted on the supporting structure (100) by four connecting rods (401, 402) distributed in pairs on each side of the seat frame (200), each connecting rod (401, 402) being articulated, on one side, on the seat frame (200), and, on the other, on the supporting structure (100).

9. Seat (10) according to one of claims 1 to 8, in which the supporting structure (100) comprises two slides (110) which each comprise a fixed rail (111) equipped with means (111 A) for fixing to the floor (20) of the motor vehicle, and a movable rail (112) which is slidably mounted in the fixed rail (111) and on which the backrest frame (300) is mounted.

10. Motor vehicle comprising a floor (20), characterized in that it comprises at least one seat (10) according to one of claims 1 to 9, the supporting structure (100) of which is fixed to the floor (20).

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