Forward extension system for a motor vehicle seat

Abstract

The invention relates to a forward extension system for a motor vehicle seat, comprising a leg extension (4) including a first (5) and a second (6) shelf and a motorized actuating device (10) for said shelves, comprising a first electric geared motor for rotating said first shelf and a second electric geared motor (12) for actuating said second shelf in longitudinal translation relative to said first shelf. This actuating device further comprises a first connecting rod (30) and a second connecting rod (32) which are rotationally linked about a third axis (34), a spreading member (35), and a worm gear (37) such that rotating said worm gear in a deployment direction results in an angular separation of said connecting rods from each other at said third axis. Figure 2a

Description

Title of the invention: System for extending a seat forward of motor vehicle seat

[0001] The invention relates to a system for extending a motor vehicle seat base forward, said system being intended to ensure reception in a substantially horizontal position of the legs of an occupant of said seat, and a motor vehicle seat comprising such a system.

[0002] It is known, in particular from document CN114506253-A, to produce a system for extending a motor vehicle seat base forward, said system being intended to ensure reception in a substantially horizontal position of the legs of an occupant of said seat, said system comprising: • an extension for receiving said legs, said extension comprising a first and a second shelf, knowing that: • said first shelf is mounted to rotate around a transverse axis arranged at the front of said seat, said first shelf having a retracted position, where it is located at the front of said seat in a substantially vertical position, and a deployed position reached by rotation upwards, where it extends said seat forwards to arrange the aspect faces of said seat and said first shelf in a substantially coplanar manner, • said second shelf is mounted to slide longitudinally relative to said first shelf, said second shelf having a retracted position, where it is arranged to cover said first shelf, and a deployed position reached by sliding forward, where it extends said first shelf forward to arrange the aspect faces of said shelves in a substantially coplanar manner, • a motorized device for actuating said shelves from one position to another, so as to reversibly move said extension from a retracted configuration to a deployed configuration, said device comprising a first electric geared motor for actuating said first shelf in rotation and a second electric geared motor for actuating said second shelf in longitudinal translation relative to said first shelf.

[0003] A problem arising with such an embodiment is to be able to have a sufficiently long extension to be able to efficiently ensure its function of reception of the legs of an occupant, and this by implementing an arrangement as simple, economical, robust and compact as possible.

[0004] The aim of the invention is to propose an arrangement making it possible to meet these expectations.

[0005] To this end, and according to a first aspect, the invention proposes a system for extending a motor vehicle seat base forward, said system being intended to ensure reception in a substantially horizontal position of the legs of an occupant of said seat, said system comprising: • an extension for receiving said legs, said extension comprising a first and a second shelf, knowing that: • said first shelf is mounted to rotate around a transverse axis arranged at the front of said seat, said first shelf having a retracted position, where it is located at the front of said seat in a substantially vertical position, and a deployed position reached by rotation upwards, where it extends said seat forwards to arrange the aspect faces of said seat and said first shelf in a substantially coplanar manner, • said second shelf is mounted to slide longitudinally relative to said first shelf, said second shelf having a retracted position, where it is arranged to cover said first shelf, and a deployed position reached by sliding forward, where it extends said first shelf forward to arrange the aspect faces of said shelves in a substantially coplanar manner, • a motorized device for actuating said shelves from one position to another, so as to reversibly move said extension from a retracted configuration to a deployed configuration, said device comprising a first electric geared motor for actuating said first shelf in rotation and a second electric geared motor for actuating said second shelf in longitudinal translation relative to said first shelf,

[0006] said actuating device further comprising: • a first connecting rod mounted in rotation by one of its ends on said first shelf, along a first axis substantially perpendicular to said aspect faces, • a second connecting rod mounted in rotation by one of its ends on said second shelf, along a second axis parallel to said first axis, said connecting rods being connected in rotation by their other respective ends according to a third axis parallel to said first axis, • a spacer member mounted in rotation by one of its ends to said connecting rods along said third axis, said member being provided with a nut mounted on its other end, • a worm screw cooperating with said nut, said screw being actuated in rotation by said second geared motor, said second geared motor being rotatably fixed on said first shelf along a fourth axis parallel to said first axis, so as to allow angular movement of said screw around said fourth axis when it is actuated in rotation by said second geared motor,

[0007] so that the rotation of said screw in a deployment direction creates an angular separation of said connecting rods from each other at the level of said third axis, so as to create an actuation of said second tablet towards its deployed position.

[0008] In this description, the terms of positioning in space (top, longitudinal, transverse, lateral, front, rear, vertical, horizontal, below, etc.) are taken with reference to the system installed in the vehicle, the extension being in the deployed configuration, said vehicle extending longitudinally along its length, transversely along its width and vertically along its height.

[0009] With the proposed arrangement, there is an extension that is long enough to efficiently perform its function of receiving the legs of an occupant, and this by implementing an arrangement that is as simple, economical, robust and compact as possible.

[0010] According to a second aspect, the invention proposes a vehicle seat comprising such a system.

[0011] Other features and advantages of the invention will appear in the following description, given with reference to the attached figures, in which:

[0012] [Fig. 1a],

[0013] [Fig.lb]and

[0014] [Fig. 1e] are schematic side views of a seat provided with a system according to one embodiment, the extension being in the retracted configuration ([Fig. 1a]), in the process of being deployed ([Fig. 1b]) and in the deployed configuration ([Fig. 1e]),

[0015] [Fig.2a] and

[0016] [Fig.2b] are schematic detail views, in perspective and from below, of the seat shown in figures 1, the second shelf being in the retracted position ([Fig.2a]) and in the deployed position ([Fig.2b]),

[0017] [Fig.3] is a schematic view in partial section of a seat showing a mode of creation of a double slide.

[0018] With reference to the figures, a system for extending forwards a seat 2 of a seat 3 of a motor vehicle is described, said system being intended to ensure reception in a substantially horizontal position of the legs of an occupant of said seat, said system comprising: • an extension 4 for receiving said legs, said extension comprising a first 5 and a second 6 shelf, knowing that: • said first shelf is mounted to rotate around a transverse axis 7 arranged at the front of said seat, said first shelf having a retracted position, where it is located at the front of said seat in a substantially vertical position, and a deployed position reached by rotation upwards, where it extends said seat forwards to arrange the aspect faces of said seat 8 and of said first shelf 9a in a substantially coplanar manner, • said second shelf is mounted to slide longitudinally relative to said first shelf, said second shelf having a retracted position, where it is arranged to cover said first shelf, and a deployed position reached by sliding forward, where it extends said first shelf forward to arrange the aspect faces of said shelves 9a, 9b in a substantially coplanar manner, • a motorized device 10 for actuating said shelves from one position to another, so as to reversibly move said extension from a retracted configuration to a deployed configuration, said device comprising a first electric geared motor, not shown, for actuating said first shelf in rotation and a second electric geared motor 12 for actuating said second shelf in longitudinal translation relative to said first shelf,

[0019] said actuating device further comprising: • a first connecting rod 30 mounted in rotation by one of its ends on said first shelf, along a first axis 31 substantially perpendicular to said aspect faces, • a second connecting rod 32 mounted in rotation by one of its ends on said second shelf, along a second axis 33 parallel to said first axis, said connecting rods being connected in rotation by their other respective ends along a third axis 34 parallel to said first axis, • a spacer member 35 - in particular in the general form of a tubular sleeve - mounted in rotation by one of its ends to said connecting rods along said third axis, said member being provided with a nut 36 mounted on its other end, • a worm screw 37 cooperating with said nut, said screw being actuated in rotation by said second geared motor, said second geared motor being fixed - laterally according to the embodiment shown - in a rotatable manner on said first shelf along a fourth axis 38 parallel to said first axis, so as to allow angular movement of said screw around said fourth axis when it is actuated in rotation by said second geared motor,

[0020] so that the rotation of said screw in a deployment direction creates an angular separation of said connecting rods from each other at the level of said third axis, so as to create an actuation of said second tablet towards its deployed position.

[0021] According to the embodiment shown, the second connecting rod 32 is mounted in rotation along the second axis 33 by means of a finger 39 mounted in a sliding manner in a slot 40 extending longitudinally, so as to absorb the dimensional dispersions of the actuating device 10.

[0022] According to an embodiment not shown, the actuating device 10 further comprises a damping means interposed between the light 40 and the finger 39 in order to avoid noise pollution.

[0023] According to one embodiment, the damping means is in the form of a sleeve made of elastomer material in which the finger 39 is fitted.

[0024] According to one embodiment, illustrated in [Fig. 3], the second shelf 6 is slidably mounted on the first shelf 5 by two double slides 19 extending laterally and in a longitudinal direction on either side of said shelves, each of said double slides comprising a first rail 23 fixed to the first shelf 5, a second rail 24 fixed to said second shelf and a support 25 for sliding reception of said first and second rails, so as to allow on the one hand maximum forward deployment of said second shelf when it is placed in the deployed position and on the other hand a force recovery to support the weight of the legs of said occupant.

[0025] According to the embodiment shown, a support 25 comprises a first groove 25a slidably receiving the first rail 23 and a second groove 25b slidably receiving the second rail 24.

[0026] The installation of double slides 19 allows on the one hand a maximized forward deployment of the second shelf 6 when it is placed in the deployed position and on the other hand a recovery of force to support the weight of the legs of the occupant of the seat.

[0027] The use of double slides 19 is particularly useful in the case of tablets 5,6 of small longitudinal dimension (measured when said tablets are placed in the deployed position), such a characteristic usually being required so that the extension 4 can be arranged in a retracted configuration without interfering with the environment of the seat 3.

[0028] It will also be noted that the maximum deployment of the second shelf 6 may be accompanied, where appropriate, by the appearance of a void between said second shelf and the first shelf 5, in particular in the case where the longitudinal dimension of said second shelf is greater than that of said first shelf.

[0029] Finally, a motor vehicle seat 3 is described comprising a system as described previously, said system being mounted at the front of the seat 2 of said seat.

Claims

1. Claims System for extending forwards a seat (2) of a motor vehicle seat (3), said system being intended to ensure reception in a substantially horizontal position of the legs of an occupant of said seat, said system comprising: • an extension (4) for receiving said legs, said extension comprising a first (5) and a second (6) shelf, knowing that: • said first shelf is mounted to rotate around a transverse axis (7) arranged at the front of said seat, said first shelf having a retracted position, where it is located at the front of said seat in a substantially vertical position, and a deployed position reached by rotation upwards, where it extends said seat forwards to arrange the aspect faces of said seat (8) and of said first shelf (9a) in a substantially coplanar manner, • said second shelf is mounted to slide longitudinally relative to said first shelf, said second shelf having a retracted position, where it is arranged to cover said first shelf, and a deployed position reached by sliding forward, where it extends said first shelf forward to arrange the aspect faces of said shelves (9a, 9b) in a substantially coplanar manner, • a motorized device (10) for actuating said shelves from one position to another, so as to reversibly move said extension from a retracted configuration to a deployed configuration, said device comprising a first electric geared motor for actuating said first shelf in rotation and a second electric geared motor (12) for actuating said second shelf in longitudinal translation relative to said first shelf, said system being characterized in that said actuating device further comprises: • a first connecting rod (30) mounted in rotation by one of its ends on said first shelf, along a first axis (31) substantially perpendicular to said aspect faces, • a second connecting rod (32) mounted in rotation by one of its ends on said second shelf, along a second axis (33) parallel to said first axis, said connecting rods being connected in rotation by their respective other ends along a third axis (34) parallel to said first axis, • a spacing member (35) mounted in rotation by one of its ends to said connecting rods along said third axis, said member being provided with a nut (36) mounted on its other end, • a worm screw (37) cooperating with said nut, said screw being actuated in rotation by said second geared motor,said second geared motor being rotatably fixed on said first shelf along a fourth axis (38) parallel to said first axis, so as to allow angular movement of said screw around said fourth axis when it is actuated in rotation by said second geared motor, so that the rotation of said screw in a direction of deployment creates an angular separation of said connecting rods from each other at said third axis, so as to actuation of said second shelf towards its deployed position.,

2. System according to claim 1, characterized in that the second connecting rod (32) is mounted in rotation along the second axis (33) by means of a finger (39) mounted in a sliding manner in a slot (40) extending longitudinally, so as to absorb the dimensional dispersions of the actuating device (10).

3. System according to claim 2, characterized in that the actuating device (10) further comprises a damping means interposed between the light (40) and the finger (39) in order to avoid noise pollution.

4. System according to claim 3, characterized in that the damping means is in the form of a sleeve made of elastomeric material

5.

6.

7. in which the finger is fitted (39). System according to any one of the preceding claims, characterized in that the second shelf (6) is slidably mounted on the first shelf (5) by two double slides (19) extending laterally and in a longitudinal direction on either side of said shelves, each of said double slides comprising a first rail (23) fixed to the first shelf (5), a second rail (24) fixed to said second shelf and a support (25) for sliding reception of said first and second rails, so as to allow on the one hand maximum forward deployment of said second shelf when it is placed in the deployed position and on the other hand a force recovery to support the weight of the legs of said occupant. System according to claim 5, characterized in that a support (25) comprises a first groove (25a) slidably receiving the first rail (23) and a second groove (25b) slidably receiving the second rail (24). Motor vehicle seat (3) comprising a system according to any one of the preceding claims, said system being mounted at the front of the seat (2) of said seat.

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