System for extending forward a seat portion of a motor vehicle seat
Patent Information
- Application Number
- EP2023732125
- Authority / Receiving Office
- EP · EP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2022-06-14
- Filing Date
- 2023-06-12
- Publication Date
- 2025-04-23
- Estimated Expiration
- Not applicable · inactive patent
AI Technical Summary
Existing forward extension systems for motor vehicle seat bases face challenges in achieving sufficient length for efficient leg reception while maintaining simplicity, economy, and compactness.
The system employs a dual-screw mechanism with an internal and external screw, where the second gear motor's nut initiates a joint rotation of the external screw, combined with double slides for maximum deployment and weight support, doubling the stroke length of the second shelf in a simple and economical manner, replacing complex articulations.
This configuration allows for enhanced forward deployment and effective weight support of the occupant's legs, ensuring a horizontal leg reception position without interfering with the vehicle's interior, while maintaining a compact design.
Smart Images
Figure 1.1
Abstract
Description
[0001] DESCRIPTION
[0002] Title: System for extending a motor vehicle seat base forward
[0003] 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.
[0004] 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:
[0005] • an extension for receiving said legs, said extension comprising a first and a second shelf, knowing that: o said first shelf is mounted to rotate about 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 forward to arrange the aspect faces of said seat and said first shelf in a substantially coplanar manner, o 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 forwards,where it extends said first shelf forward to arrange the aspect faces of said shelves in a substantially coplanar manner,
[0006] • 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.
[0007] A problem with such an implementation is to be able to have an extension long enough to efficiently ensure 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.
[0008] The invention aims to propose an arrangement that makes it possible to meet these expectations.
[0009] 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:
[0010] • an extension for receiving said legs, said extension comprising a first and a second shelf, knowing that: o said first shelf is mounted to rotate about 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 forward to arrange the aspect faces of said seat and said first shelf in a substantially coplanar manner, o 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 forwards,where it extends said first shelf forward to arrange the aspect faces of said shelves in a substantially coplanar manner,
[0011] • 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, said device further comprising:
[0012] • a nut actuated in rotation by said second geared motor, said second geared motor being fixed on said second shelf,
[0013] • an internal worm screw extending longitudinally and being fixed by its rear end to the rear of said first tablet,
[0014] • an endless external screw, said external screw being provided with a threaded axial channel receiving said internal screw in screwing, the front end of said external screw being provided with a collar so that said nut comes into abutment against said collar when said second geared motor is brought to the end of its forward travel and initiates a joint rotation of said external screw with said nut, said rotation effecting a rearward extraction of said internal screw from said external screw to extend the forward travel of said second shelf, said second shelf being slidably mounted on said first shelf by two double slides extending laterally and in a longitudinal direction on either side of said shelves, each of said double slides comprising a first rail fixed to said first shelf,a second rail fixed to said second shelf and a support for receiving said first and second rails in a sliding manner, so as to allow on the one hand a 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. 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 in place in the vehicle, said vehicle extending longitudinally along its length, transversely along its width and vertically along its height.,
[0015] With the proposed arrangement, using two screws inserted into each other, the stroke length of the second shelf is substantially doubled, and this in a simple, compact and economical manner, particularly in comparison with systems using, as in the CN1 14506253-A production, complex joints using connecting rods.
[0016] Furthermore, the installation of double slides allows on the one hand a maximized forward deployment of the second shelf when it is put in the deployed position and on the other hand a recovery of force to support the weight of the legs of the seat occupant.
[0017] The use of double slides is necessary in the case of tablets of small longitudinal dimension (measured when the tablets are placed in the deployed position), such a characteristic being usually required so that the extension can be arranged in a retracted configuration without interfering with the environment of the seat.
[0018] It will be noted here that the maximum deployment of the second shelf may be accompanied, where appropriate, by the appearance of a void between said second shelf and the first shelf, in particular in the case where the longitudinal dimension of said second shelf is greater than that of said first shelf.
[0019] According to a second aspect, the invention provides a vehicle seat comprising such a system. Other features and advantages of the invention will appear in the following description, given with reference to the attached figures in which:
[0020] [Fig.1a],
[0021] [Fig.1b] and
[0022] [Fig.1c] are schematic side views of a seat provided with a system according to one embodiment, the extension being in the retracted configuration (figure 1a), being deployed (figure 1b) and in the deployed configuration (figure 1c), [Fig.2] is a schematic perspective view of an actuating device according to one embodiment,
[0023] [Fig.3] is a schematic perspective view of the actuating device of Figure 2 integrated into a seat seen from below, the extension being in the retracted configuration,
[0024] [Fig.4a],
[0025] [Fig.4b] and
[0026] [Fig.4c] are partial schematic top views of the actuating device of figures 2 and 3 corresponding to the retracted position of the second shelf (figure 4a), to its partial deployment (figure 4b) and to its deployed position (figure 4c),
[0027] [Fig.5] is a schematic view in partial section of a seat showing one embodiment of a double slide.
[0028] 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:
[0029] • an extension 4 for receiving said legs, said extension comprising a first 5 and a second 6 shelf, knowing that: o said first shelf is mounted to rotate about 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 said first shelf 9a in a substantially coplanar manner, o 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 forwards,where it extends said first shelf forward to arrange the aspect faces of said shelves 9a, 9b in a substantially coplanar manner,
[0030] • 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 11 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 device further comprising:
[0031] • a nut 13 - here toothed on its periphery - actuated in rotation by said second geared motor, said second geared motor being fixed on said second shelf,
[0032] • an internal worm screw 14 extending longitudinally and being fixed by its rear end 15 to the rear of said first shelf,
[0033] • an endless external screw 16, said external screw being provided with a threaded axial channel 17 receiving said internal screw in screwing, the front end of said external screw being provided with a collar 18 so that said nut comes into abutment against said collar when said second geared motor is brought to the end of its forward travel and initiates a joint rotation of said external screw with said nut, said rotation effecting a rearward extraction of said internal screw from said external screw to extend the forward travel of said second shelf, said second shelf being slidably mounted on said first shelf 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 said first shelf,a second rail 24 fixed to said second shelf and a support 25 for receiving said first and second rails in sliding manner, 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 recovery of force to support the weight of the legs of said occupant.,
[0034] According to the embodiment shown in Figure 5, 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.
[0035] According to the embodiment shown, the axis 20 of the motor is parallel to that 21 of the worm screws 14, 16, so as to avoid angle returns in the gears and minimize the size of the second geared motor 12.
[0036] According to an embodiment not shown, the second geared motor 12 and the nut 13 are mounted in a pendulum manner to be able to move freely according to a transverse clearance and absorb dimensional dispersions, so as to avoid blocking by arching of the actuating device 10.
[0037] Finally, a motor vehicle seat 3 is described comprising such a system, said system being mounted at the front of the seat 2 of said seat.
Claims
DEMANDS 1. A system for extending forward the leg support (2) of a motor vehicle seat (3), said system being intended to ensure that the legs of an occupant of said seat are received in a substantially horizontal position, said system comprising: • an extension (4) for receiving said legs, said extension comprising a first (5) and a second (6) shelf, knowing that: o said first shelf is mounted to rotate about a transverse axis (7) disposed 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 facings of said seat (8) and of said first shelf (9a) in a substantially coplanar manner, o said second shelf is mounted to slide longitudinally relative to said first shelf, said second shelf having a retracted position, where it is disposed overlapping said first shelf, and a deployed position reached by sliding forwards,where it extends said first tablet forwards to arrange the front faces of said tablets (9a, 9b) in a substantially coplanar manner, • a motorized actuating device (10) for moving said tablets 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 (11) for actuating said first tablet in rotation and a second electric geared motor (12) for actuating said second tablet in longitudinal translation relative to said first tablet, said system being characterized in that said device further comprises: • a nut (13) actuated in rotation by said second geared motor, said second geared motor being fixed on said second shelf, • an internal worm screw (14) extending longitudinally and being fixed by its rear end (15) to the rear of said first shelf, • an external worm screw (16), said external screw being provided with a threaded axial channel (17) receiving said internal screw, the front end of said external screw being provided with a collar (18) so that said nut abuts against said collar when said second geared motor is brought to the end of its forward stroke and initiates a joint rotation of said external screw with said nut, said rotation effecting a rearward extraction of said internal screw from said external screw to extend the forward stroke of said second shelf, said second shelf being mounted to slide on said first shelf 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 said first shelf,a second rail (24) fixed to said second shelf and a sliding receiving support (25) for said first and second rails, so as to allow, on the one hand, maximum forward deployment of said second shelf when it is in the deployed position and, on the other hand, a load transfer to support the weight of the legs of said occupant.
2. System according to claim 1, characterized in that a support (25) comprises a first groove (25a) receiving the first rail (23) in sliding motion and a second groove (25b) receiving the second rail (24) in sliding motion.
3. System according to any one of the preceding claims, characterized in that the axis of the motor (20) is parallel to that (21) of the worm gears.
4. System according to any one of the preceding claims, characterized in that the second geared motor (12) and the nut (13) are mounted in a pendulum-like manner to allow free movement according to a transverse play and to absorb dimensional dispersions, so as to avoid jamming of the actuation device (10).
5. 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.