Tilting seat frame

Abstract

The invention relates to a seat frame comprising: - a backrest frame, - a seat frame, and - means for assembling the backrest frame onto the seat frame, which include, on each side of the seat, two fastening systems, at least one of the fastening systems (32) comprising, on the one hand, an axle (322) that passes through two openings (210, 310) provided in walls (21, 31) of the backrest and / or seat frames, and, on the other hand, two stops (321, 329) bearing on either side of said walls to prevent the axle from coming out of the openings. According to the invention, each first fastening system is equipped with a pyrotechnic charge (325) adapted to be activated to allow the backrest frame to move relative to the seat frame. Figure for the abstract: Fig. 3

Description

Title of the invention: Tilting seat frame Technical field of the invention

[0001] The present invention relates generally to the field of seats.

[0002] It relates more particularly to a seat frame comprising: - a backrest frame, - a seat frame, and - means for assembling the backrest frame with the seat frame, which comprise, on each side of the seat frame, two fixing systems such as bolts.

[0003] The invention also relates to a seat comprising such a frame, and a vehicle equipped with such a seat. State of the art

[0004] Currently, driver's seats installed in motor vehicles allow drivers to adjust their driving positions. Passenger seats in these vehicles can also be equipped with this function.

[0005] These seats are of two types, namely manually operated and electrically operated.

[0006] Typically, a seat is known comprising a seat frame and a backrest frame articulated to each other by means of two "gussets" located on either side of the seat. Each gusset is in the form of a metal part which is fixed by two bolts to the seat frame and which has an opening at the level of which the backrest is articulated so that it can tilt forwards or backwards.

[0007] These frames are designed so as not to deform excessively in the event of an accident. However, it happens that during an impact, the vehicle chassis or the seat frame deforms despite everything and it is difficult to extricate the occupants of the vehicle.

[0008] In this eventuality, the solution currently used consists of cutting the vehicle's uprights so as to remove the roof to provide easier access to the victims.

[0009] Unfortunately, this solution requires the use of powerful cutting pliers, which emergency services must be equipped with. Even if they had them, this operation takes a long time to implement, which can have serious consequences for the victims. Presentation of the invention

[0010] It is in this context that the applicant sought new solutions for facilitate the extrication of victims.

[0011] One idea is to tilt the backrest backwards, horizontally, so that they can be extracted through the luggage compartment.

[0012] For this purpose, the aforementioned mobility of tilting the backrest relative to the seat could be used.

[0013] But whether the seat is manually or electrically controlled, it happens that the tilting mobility of the backrest is blocked due to deformation of the seat frame or the vehicle chassis or even a power cut.

[0014] This solution is therefore not satisfactory. It is even less so since the tilting axis of the backrest is generally located above the seat plane, so that by tilting the backrest completely backwards, the latter would form a sort of step with the seat which could prevent the victim from being extracted.

[0015] The present invention then proposes to allow the backrest to tilt using means separate from this articulation.

[0016] More particularly, in the context of the invention, a seat frame is used as defined in the introduction, the means of which for assembling the backrest frame on the seat frame comprise, on each side of the seat frame, two fixing systems, in particular a first fixing system comprising, on the one hand, an axis which passes through two openings provided in walls of the backrest and / or seat frames, and, on the other hand, two stops bearing on either side of said walls to prevent the axis from coming out of the openings.

[0017] The invention then proposes that each first fixing system is equipped with a pyrotechnic charge which is adapted to be activated to explode and release mobility of at least part of the backrest frame relative to at least part of the seat frame.

[0018] Thus, when the pyrotechnic charge is activated, it causes the axis or one of the stops to deform or break, so that the first fixing system can no longer perform its initial function of fixing the backrest relative to the seat.

[0019] Preferably, gussets are provided on either side of the seat, which are fixed to the seat frame (or respectively the backrest) and which form an articulation for the backrest frame (or respectively the seat frame). The invention then proposes to use the means for fixing these gussets to the seat frame (or respectively the backrest) in order to allow, in the event of an emergency, the backrest of the seat to be tilted backwards.

[0020] Thus, thanks to the invention, it is possible to unlock part of the fixing points of the gussets on the seat frame (or respectively backrest) so as to allow the backrest to tilt backwards. It is understood in fact that if each gusset is fixed to the rest of the seat frame by two bolts, the breakage of one at less bolts then allows the other bolt to be used as a hinge to tilt the backrest.

[0021] It will be noted that preferably, each first fixing means will be designed in such a way that it is possible to tilt the backrest without having to manually remove the broken pieces of bolts. Indeed, if it were necessary to completely remove the axles once broken, it would be necessary to have a lot of space on either side of the seat, which is not necessarily the case, particularly when the chassis of the vehicle has become deformed.

[0022] It should also be noted that all four bolts could be fitted with a pyrotechnic charge. Thus, if the emergency services consider that it is preferable not to tilt the backrest backwards but to remove it completely from the vehicle, this remains possible.

[0023] Other advantageous and non-limiting characteristics of the seat frame according to the invention, taken individually or in all technically possible combinations, are the following: - said pyrotechnic charge is provided inside said axis and is adapted to break said axis; - said axis has a fusible zone of lower resistance; - said pyrotechnic charge is adapted to break said axis at said fusible zone; - said axis has an annular groove which delimits said fusible zone and said pyrotechnic charge is located inside said fusible zone; - said fusible zone is centered in a support plane of said two walls; - one of the stops forms a screw with the axis, and the other of the stops forms a bolt screwed onto said screw; - said pyrotechnic charges are controlled via electrical wires, the ends of which, located opposite said pyrotechnic charge, are fixed in the same electrical connection terminal block; - the other fixing system is adapted to form a hinge to allow, when the mobility of the backrest frame relative to the seat frame is released, the tilting of the backrest frame relative to the seat frame; - the four fixing systems are equipped with pyrotechnic charges which, when activated, are suitable for decoupling the backrest frame from the seat frame.

[0024] The invention also relates to a seat comprising a frame as mentioned above, the seat frame and the back frame of which are covered with a pad.

[0025] It also relates to a motor vehicle equipped with such a seat. Of course, the various characteristics, variants and embodiments of the invention may be associated with each other in various combinations as long as they are not incompatible or mutually exclusive. Detailed description of the invention

[0026] 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.

[0027] In the attached drawings:

[0028] [Fig-1] is a schematic perspective view of a motor vehicle seat in accordance with the invention;

[0029] [Fig.2] is a schematic view of part of the means for assembling the frames seat and backrest of the seat frame of [Fig.l];

[0030] [Fig.3] illustrates two schematic sectional views, according to plane AA of [Fig.2], of a fixing system before and after activation of its pyrotechnic charge;

[0031] [Fig.4] is a schematic side view of the seat frame of [Fig.l], after activation of the pyrotechnic charge.

[0032] A motor vehicle (car, bus, truck, boat, airplane, etc.) generally has a chassis and bodywork elements which delimit a passenger compartment.

[0033] In [Fig.l], there is shown a seat 1 intended to be installed in the passenger compartment of such a motor vehicle and to be fixed to the floor of this motor vehicle.

[0034] In the remainder of the description, the terms “front” and “rear” will be used in relation to the motor vehicle, 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.

[0035] 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.

[0036] 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.

[0037] The adjective "transverse" will apply to a direction or axis oriented orthogonally to the longitudinal axes and horizontally when the vehicle is traveling on a horizontal road.

[0038] The adjectives “internal” and “external” will be used in relation to seat 1, an external face being for example turned towards the outside of the seat when an internal face is turned towards the geometric center of the seat.

[0039] As shown in [Fig.l], the seat 1 conventionally comprises a seat 20A, a backrest 10A and a headrest 30A, each comprising a frame and a trim attached to the frame. Note that the frame of the backrest and that of the headrest could be confused.

[0040] As shown in [Fig.4], the frame 2 of the seat is therefore composed of at least one seat frame 20 and one backrest frame 10. Each of these frames is for example formed of metal parts fixed together.

[0041] Here, it will be considered that the backrest frame 10 and the seat frame 20 each comprise two metal lateral flanks 11, 21, rigidly connected together by metal connecting elements (not visible). The two lateral flanks 11, 21 of each frame extend in parallel vertical planes. Of course, as a variant, these frames could be presented differently, for example in the form of plastic shells.

[0042] The seat frame 20 could be rigidly fixed to the floor of the vehicle, but it is generally rather intended to be mounted mobile in translation on the floor. As shown in [Fig.l], it is mounted for this purpose on two longitudinal slides 40A each formed of a mobile rail fixed to the seat frame 20, and a fixed rail fixed to the floor and in which the mobile rail slides.

[0043] The backrest frame 10 could be rigidly fixed to the seat frame 20 so that the inclination of the backrest is not adjustable, but it is generally rather designed to be mounted mobile in tilting on the seat frame around a transverse geometric axis, hereinafter called pivot axis A2 (see [Fig.2]).

[0044] In this [Fig. 2], the area ensuring the connection between the lateral flanks 11, 21 of these two frames is shown in detail. It will be noted here that the connection is ensured in the same way on both sides of the seat, so that in the following, only one of them shown in Figures 2 and 3 will be described here.

[0045] Here, this connection is ensured by assembly means 30 which firstly comprise a metal wall called a gusset 31, which here results from a stamping operation of a sheet metal part.

[0046] This gusset 31 is designed to connect one of the lateral flanks 11 of the backrest frame 10 to one of the lateral flanks 21 of the seat frame 20.

[0047] In the illustrated embodiment, the gusset 31 is fixed to the lateral flanks 21 of the seat frame 20 (it is therefore considered to be part of this seat frame), and the backrest frame 10 is articulated on it around the pivot axis A2.

[0048] As shown in Figures 2 and 4, the gusset 31 is placed on the inside of the lateral sides 21 of the seat frame 20, but alternatively, it could be placed on the outside.

[0049] This gusset 31 generally has a triangular shape with vertices rounded, and it has three openings located near its peaks, the first two openings being lower than the third.

[0050] These two first openings 310 are identical here.

[0051] As shown for one of them in [Fig. 3], they preferably have circular shapes. They are located opposite two openings 210 provided in correspondence in the lateral flank 21 of the seat frame 20. These openings 210, 310 here have similar dimensions. Thus, each of the first openings 310 overlaps with an opening 210 provided in correspondence in the lateral flank 21 of the seat frame 20.

[0052] The third opening ([Fig.2]), the one located highest in the gusset 31, is designed to allow the backrest 10A to tilt around the pivot axis A2. For this purpose, it accommodates, for example, a hinge axis 35 fixed to the backrest frame 10. This assembly being well known to those skilled in the art, it will not be described in detail here.

[0053] In addition to this gusset 31, the assembly means 30 of the backrest frame 10 on the seat frame 20 comprise two fixing systems 32, 33 each engaged through one of the first two openings 310 of the gusset and the corresponding opening 210 provided in the lateral flank 21 of the seat frame 20 in order to rigidly fix the gusset 31 to this lateral flank 21.

[0054] In this configuration illustrated in [Fig.2], these two fixing systems 32, 33 are in the use configuration.

[0055] These two fixing systems 32, 33 are provided so that if necessary, at least one of them can give way. It will be considered here that only one of these two fixing systems 32, 33 can give way, the other forming a hinge so that the gusset and the backrest can pivot backwards, as illustrated in [Fig.4]. Alternatively, the two fixing systems 32, 33 can be designed to give way.

[0056] In the embodiment illustrated in the figures, the fixing system 32 which is intended to yield is the one which is engaged through the front opening of the gusset 31, while the fixing system 33 which is intended to allow the backrest to tilt relative to the seat is the one located furthest to the rear.

[0057] The front fixing system 32 is the one which is more precisely the subject of the present invention.

[0058] This fixing system comprises an axis which passes through the two openings 211, 311 and which is equipped with two stops mounted on this axis, on either side of the gusset 31 and the lateral flank 21 of the seat frame 20.

[0059] More precisely, as shown in [Fig. 3], this fixing system 32 is in the form of a bolt comprising a so-called safety screw 320 and a bolt 329 (forming one of said stops). The safety screw 320 comprises a head 321 (forming the other of said stops) and a threaded body 322 (forming said axis). Here it comprises in in addition to a free, unthreaded end located in the extension of the threaded body 322.

[0060] The head 321 of the security screw 320 has a hexagonal-shaped top. Of course, it could have a different shape (for example, an imprint for an Allen key).

[0061] The safety screw 320 is elongated along a geometric axis passing through the centers of the aforementioned openings, hereinafter called the safety geometric axis AL.

[0062] It is here oriented such that its head 321 is located on the outside of the seat 1, so as to be easily accessible. This head 321 then rests against the outside face of the lateral flank 21 of the seat frame 20 while the nut 329 rests against the inside face of the gusset 31.

[0063] This bolt makes it possible to retain the gusset 31 in abutment against the lateral flank 21 of the seat frame 20.

[0064] This safety screw 320 is special in that it is equipped with a pyrotechnic charge 325.

[0065] This load could be located outside the screw. However, for reasons of safety and ease of use in particular, it is preferably housed inside the safety screw 320, and more precisely here inside the threaded body 322 of this screw.

[0066] The bolt is therefore designed to break when the load is activated.

[0067] The bolt formed from the safety screw 320 and the nut 329 could be of the type ejector, generating an ejection effect of the two pieces of the bolt after the explosion of the pyrotechnic charge 325.

[0068] However, for safety reasons, the bolt will rather be of the traction type, generating no thrust on the two parts of the bolt after the explosion of the pyrotechnic charge 325.

[0069] Therefore, it is preferable for its breakage to be carried out in such a way that it is not then necessary to extract the two pieces of bolts from the openings 210, 310 in order to release the tilting mobility of the backrest. In other words, if the load caused the breakage of the head of the safety screw or the bolt, the threaded body 322 of the screw would remain located through these two openings so that it would then be necessary to manually remove this threaded body in order to release the tilting mobility of the backrest. This is the reason why the pyrotechnic charge 325 is preferably housed in the threaded body 322.

[0070] To ensure that the bolt breaks in the plane where the gusset bears against the lateral flank 21 of the seat reinforcement 20, the threaded body 322 has a fusible zone 323 located between the head 321 and the threaded part of the threaded body 322.

[0071] In practice, the threaded body 322 has an annular groove of revolution around the safety axis Al, which therefore forms a reduction in section and thus a fusible zone.

[0072] This groove extends hollow relative to the rest of the threaded body 322. It has an invariable profile all around the geometric safety axis A1 but as a variant, it could be otherwise. Typically, it could be formed of a plurality of radial holes distributed all around this axis.

[0073] In any case, the fusible zone 323 makes it possible to locally significantly reduce the tensile strength of the safety screw 320.

[0074] Thus, the rupture of the safety screw 320, when it is put under stress due to the explosion of the pyrotechnic charge 325, gives way in the plane passing through the bottom of the annular groove.

[0075] This annular groove is positioned along the safety screw 320 so that, once the nut is tightened onto the screw, the bottom of the groove is in the support plane of the gusset against the lateral flank 21 of the seat frame 20.

[0076] Furthermore, the pyrotechnic charge is housed in the threaded body 322 of the safety screw, at the level of this support plane.

[0077] Thus, after the explosion of the pyrotechnic charge 325, it will then be possible to slide the gusset 31 against the lateral flank 21 (without removing the pieces of the bolt) to allow the backrest to tilt backwards, into the position illustrated in [Fig.4].

[0078] As shown in [Fig.3], the pyrotechnic charge 325 is intended to be electrically activated. It is therefore connected to a sheathed electrical wire 326.

[0079] Here, the sheathed electrical wires 326 of the pyrotechnic charges 325 provided on either side of the backrest meet at their ends, and are connected to the same terminal block. This terminal block is for example located under the seat cover (invisibly), so that emergency service personnel can connect a portable battery to it if necessary in order to detonate the charges and cause the safety screws 320 to break.

[0080] As shown in [Fig.2], the other fastening system 33, the one engaged through the rear opening of the gusset 321, is here in the form of a bolt.

[0081] The tightening torque of this bolt will preferably be such that, when the gusset 31 is fixed to the seat frame 20 by this single bolt (on each side of the seat), it is possible to manually force the backrest to tilt backwards, around the geometric axis of this bolt, hereinafter called hinge axis A3. Thus this bolt can act as a hinge.

[0082] It could be a classic bolt (without fusible zone), standard M8 or M10.

[0083] However, preferably, it will be a bolt identical to that of the 32 fixing system (with a fusible zone and a pyrotechnic charge). This will not only limit the number of part numbers required for seat assembly, but also allow the backrest to be completely separated from the seat if necessary, causing the four screws fixing the gussets to break.

[0084] Then, the electrical wires of the four bolts will be connected within the same electrical connection terminal block accessible to the emergency services. However, the electrical wires 326 of the pyrotechnic charges 325 of the front fixing systems 32 will not be electrically connected to the electrical wires of the pyrotechnic charges of the rear fixing systems 33, so as to leave the emergency services the choice of releasing only the tilting mobility of the backrest towards the rear, or of completely uncoupling the backrest so as to be able to extract it from the passenger compartment.

[0085] It is now possible to describe how, in the event of an accident, the emergency services can operate if they wish to extract the occupant from the vehicle by passing them through the luggage compartment.

[0086] The first operation will consist of possibly removing rear seats from the vehicle which would hinder access to seat 1 where the victim is located.

[0087] Then, it will be possible to cause the safety screws 320 located on both sides of the seat 1 to break, by applying an electrical voltage to the terminals of the pyrotechnic charges 325. For this, the emergency services will be able to use an external power supply.

[0088] The breaking of the safety screws 320 occurring in the support plane of the gussets 31 against the lateral flanks 21 of the seat frame 20, the pieces of bolt will not prevent an individual from forcing the backrest 10A to tilt around the hinge axis A3, without tools.

[0089] The present invention is in no way limited to the embodiment shown, but those skilled in the art will be able to provide any variant in accordance with the invention.

[0090] Typically, the bolt engaged in the rear opening of the gusset (along the hinge axis) could be replaced by a shouldered axis equipped with a circlip, such an axis forming a perfect hinge.

[0091] Similarly, the bolt engaged in the front opening of the gusset (the one that incorporates the pyrotechnic charge) could be replaced by a shouldered pin equipped with a circlip or a pin. Alternatively, the safety screw could not have a fusible zone and the circlip or the pin could be designed to yield. This variant is not preferred, however, since it would require the safety screws to then be removed from the openings to tilt the seat back.

[0092] In another variant, the openings provided in the gusset or the lateral flank of the seat frame could have shapes different from those illustrated in the figures (typically octagonal).

[0093] In one embodiment, the gusset could be located on the outer side of the sidewall. side of the seat frame. The safety screw could then possibly be oriented head to tail compared to the illustrated embodiment, with its head oriented towards the inside of the seat.

[0094] In another embodiment, the gusset could belong not to the seat frame but to that of the backrest. In this mode, the two fixing systems (32, 33) would therefore make it possible to fix the gusset to the corresponding lateral side of the backrest.

[0095] In yet another embodiment, the backrest frame could be fixed to the seat frame without any mobility. In this variant, the two bolts provided on each side of the seat would therefore allow one of the frames to be fixed directly to the other of the frames.

[0096] In yet another embodiment, the seat frame could comprise, in addition to the two lateral flanks fixed by the crosspieces, a support fixed to the movable rails and connecting rods which are interposed between the lateral flanks and this support. This system of connecting rods would make it possible to raise or lower the seat surface relative to the floor of the vehicle. In this mode, the backrest frame would then be coupled, not to the lateral flanks of the seat frame, but to the support itself.

Claims

Claims

1. Seat frame (2) comprising: - a backrest frame (10), - a seat frame (20), and - means (30) for assembling the backrest frame (10) on the seat frame (20), which comprise, on each side of the seat frame (2), two fixing systems (32, 33), at least a first of said two fixing systems (32) comprising, on the one hand, an axis (322) which passes through two openings (210, 310) respectively provided in two walls (21, 31) of the backrest (10) and / or seat (20) frames, and, on the other hand, two stops (321, 329) bearing on either side of said two walls (21, 31) to prevent the axis (322) from coming out of the openings (210, 310), characterized in that each first fixing system (32) is equipped with a pyrotechnic charge (325) which is adapted to be activated to release mobility of the backrest frame (20) relative to the seat frame (10).

2. A seat frame (2) according to claim 1, wherein said pyrotechnic charge (325) is provided inside said axis (322) and is adapted to break said axis (322).

3. Seat frame (2) according to claim 1 or 2, in which said axis (322) has a fusible zone (323) of less resistance, and said pyrotechnic charge (325) is adapted to break said axis (322) at the level of said fusible zone (323).

4. Seat frame (2) according to claims 2 and 3, wherein said axis (322) has an annular groove which delimits said fusible zone (323) and said pyrotechnic charge (325) is located inside said fusible zone (323).

5. Seat frame (2) according to claim 3 or 4, in which said fusible zone (323) is centered in a support plane of said two walls (21, 31).

6. Seat frame (2) according to one of claims 1 to 5, in which one of the stops (321) forms with the axis (322) a screw (320), and the other of the stops (329) forms a bolt screwed onto said screw (320).

7. Seat frame (2) according to one of claims 1 to 6, in which said pyrotechnic charges (325) are controlled via electric wires (326) whose ends are located opposite said charge pyrotechnic (325) are fixed in the same electrical connection terminal block.

8. Seat frame (2) according to one of claims 1 to 7, in which the other fixing system (33) is adapted to form a hinge to allow, when the mobility of the backrest frame (20) relative to the seat frame (10) is released, the tilting of the backrest frame (10) relative to the seat frame (20).

9. Seat frame (2) according to one of claims 1 to 8, in which the four fixing systems (32, 33) are equipped with pyrotechnic charges (325) which, when activated, are adapted to decouple the backrest frame (20) from the seat frame (10).

10. Seat (1) comprising a frame (2) according to one of claims 1 to 9, the seat frame (20) and the backrest frame (10) of which are covered with a pad.

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