FR3055853A1 - DEVICE FOR DAMPING A SEAT OF A MOTOR VEHICLE BY PRE-CONTAINED BLADE SPRING - Google Patents

Abstract

A device (3) for damping a seat comprising a frame (5) movable relative to a support (9) comprising at least one rail (10) in which slides a slide (11), the device comprising at least one leaf spring disposed between the armature and the support, so as to retain the displacement of the armature, the leaf spring comprising a first section (33) bearing against a roller (36) integral with a stirrup (38) rotatably mounted with the device, the yoke being attached to the rail by means of a resilient member such as a coil spring (43) expandable at a minimum elongation at maximum elongation.

Description

Holder (s): PEUGEOT CITROEN AUTOMOBILES SA Société anonyme.

Extension request (s)

Agent (s): PEUGEOT CITROEN AUTOMOBILES SA Public limited company.

(54) DEVICE FOR DAMPING A MOTOR VEHICLE SEAT BY PRE-STRESSED BLADE SPRING.

FR 3 055 853 - A1 _ A device (3) for cushioning a seat comprising a frame (5) movable relative to a support (9) comprising at least one rail (10) in which slides a slide (11) , the device comprising at least one leaf spring disposed between the frame and the support, so as to retain the movement of the frame, the leaf spring comprising a first section (33) bearing against a roller (36) integral a stirrup (38) rotatably mounted with the device, the stirrup being attached to the rail by means of an elastic member such as a spring (43) with extensible turns in a minimum elongation to a maximum elongation.

DEVICE FOR DAMPING A VEHICLE SEAT

AUTOMOTIVE BY SPRING WITH PRE-STRESSED BLADE The invention relates to the field of vehicles, in particular motor vehicles. More specifically, it relates to the depreciation of a vehicle seat, in particular an automobile seat.

The road behavior of a vehicle directly influences the comfort of the occupants in the front seats, and comfort is also linked to safety, and therefore to the health of the occupants.

Uncomfortable seats increase the irritation and fatigue of a driver, and prolonged postural stresses can cause lumbar problems. This damage is aggravated by the vibrations transmitted by the vehicle to the occupants.

If in the automotive field the amplitudes of vibration transmitted remain relatively low, the same is not true for industrial vehicles. In this area, the vibrations transmitted are of high amplitude and constitute a real problem for the health of operators.

A vehicle seat is conventionally composed of a frame supporting the seat, and this frame, in direct contact with the base of the vehicle, is sensitive to all the vibrations generated by the road behavior of the vehicle, these vibrations being transmitted. by the base to the seat frame.

Seats aimed at solving the drawbacks mentioned above have been proposed, and are for example used for heavy goods vehicles or tractors.

However, the size of such seats does not allow their establishment in other types of vehicles, including cars. Document US 20140216242 describes a device for damping a seat, comprising a frame movable relative to a support, between an initial position and a load position, the device comprising a plurality of leaf springs, arranged between the armature and the support, so as to retain the displacement of the armature.

Such a device can effectively cushion a seat when subjected to a large load. However, the leaf springs occupy a large space in the device, and when the frame is in the initial position, an empty space is located between the frame and the support. This empty space has no function, except to contain all of the springs when the armature is in the load position.

In addition, this device does not adjust the stiffness of the leaf springs, to adapt the cushioning of the seat to the weight and size of an occupant seated on the seat.

A first objective is to provide a device for damping a vehicle seat, in particular an automobile seat, which is compact, so that it can be integrated into a wide variety of vehicles, in particular motor vehicles.

A second objective is to provide a device for damping a vehicle seat, in particular an automobile seat, which adapts to the weight and size of an occupant of the vehicle, seated on the seat.

To this end, it is proposed, firstly, a device for damping a seat comprising a frame movable relative to a support comprising at least one rail in which slides a slide, the device comprising at least one leaf spring disposed between the armature and the support, so as to retain the movement of the armature, the leaf spring comprising a first section in abutment against a roller secured to a stirrup mounted in rotation with the device, the stirrup being attached to the rail by means of an elastic member such as a coil spring extendable with a minimum elongation to a maximum elongation.

Advantageously, such a damping device allows a vehicle seat to properly collect the vibrations transmitted by the underbody of a vehicle, without degrading the comfort of an occupant seated on said seat.

In addition, this device allows to adapt the cushioning of the seat to the size and weight of an occupant of a vehicle seated on said seat, by adjusting the stiffness of the leaf spring.

Various additional characteristics can be provided, alone or in combination:

- the leaf spring is contained in a cassette fixed to a plate integral with the slide;

- The frame comprises a sliding axis in a first groove dug in the cassette;

- The first section of the leaf spring is wound around an anchor pin;

- The leaf spring comprises a second section extending the first section and being supported on the axis;

- the cassette is hollowed out with a second groove in which the roller slides between two positions:

o a high position, in which the elastic member such as a coil spring is in maximum elongation, the seat being in the retracted position, o a low position, in which the elastic member such as a coil spring is in minimal elongation, the seat being in the forward position.

It is proposed, secondly, a seat comprising the damping device as presented above.

It is proposed, thirdly, a vehicle, in particular a motor vehicle, comprising such a seat.

Other characteristics and advantages of the invention will appear more clearly and concretely on reading the following description of embodiments, which is made with reference to the accompanying drawings in which:

- Figure 1 is a perspective view of a motor vehicle (in dotted lines) comprising a seat (in solid bold lines) provided with a damping device;

- Figure 2 is an exploded perspective view of the seat of Figure 1 provided with a frame;

- Figure 3 is an exploded perspective view of the frame of Figure 2;

- Figure 4 is an exploded perspective view of the frame of Figure 2, comprising the damping device;

- Figure 5 is an exploded perspective view of the damping device;

- Figure 6 is a side view of the damping device, according to an initial position and a first configuration;

- Figure 7 is a side view of the damping device, according to a loading position and the first configuration;

- Figure 8 is a side view of the damping device, according to an initial position and a second configuration;

- Figure 9 is a side view of the damping device, according to a loading position and the second configuration.

In Figure 1 is shown a motor vehicle 1 (in dotted lines) comprising a seat 2 (in solid bold lines) allowing an occupant of the motor vehicle to sit.

The motor vehicle 1 can for example be a private vehicle or a utility vehicle.

An orthogonal coordinate system XYZ is defined with respect to vehicle 1 comprising three perpendicular axes two by two, namely:

- an X axis, defining a longitudinal, horizontal direction, coincident with the general direction of movement of the vehicle,

- a Y axis, defining a transverse, horizontal direction, which with the X axis defines a horizontal XY plane,

- a Z axis, defining a vertical direction, perpendicular to the horizontal XY plane.

In the following description and with reference to the reference defined above, the terms "longitudinal" or "longitudinally" refer to a direction coincident with the axis X, the terms "transverse" or "transversely" do reference to a direction confused with the Y axis, and the terms "vertical" or "vertically" refer to a direction confused with the Z axis.

As illustrated in FIG. 2, the seat 2 comprises:

- a damping device 3,

- a backrest 4 allowing the occupant to keep a good sitting posture by properly restraining his back,

a frame 5 with which the backrest 4 is rotatably mounted, so that the occupant can manage its inclination, the frame 5 being movable between an initial position and a load position,

- A seat 6 comprising a fixed cushion 7 secured to the frame 5 and a movable cushion 8 disposed on the device 3 and mounted in rotation, along the Y axis, with the frame 5 so that the movable cushion 8 can tilt,

- A support 9 provided with two rails 10 in which two slides 11 slide, allowing the positioning and the maintenance in position of the frame 5, the support 9 being integral with a base of the motor vehicle 1.

As illustrated in Figure 3, the frame 5 comprises a first side 12 spaced from a second side 13, the two sides 12, 13 being secured by means of a bar 14 of front connection and a rear link bar 15. The connecting bars 14, 15 allow both to form a frame with the sides 12, 13 and to stiffen the frame 5. The frame 5 comprises a cross member 16 before, mounted on the two sides 12, 13 and extending transversely from the first side 12 to the second side 13. The front cross member 16 makes it possible to set up and hold in position the fixed cushion 7.

In some implementations, the front cross member 16 comprises a surface 17 on which is mounted a base (not shown) of the seat 6, the surface 17 comprising a plurality of holes 18, so as to secure the base of the cross member 16 before, for example by means of hooks. The base also rests on the rear connecting bar 15, so as to be fixed relative to the frame 5. As illustrated in FIG. 4, the frame 5 is articulated, at a rear end 19 of the sidewalls 12, 13, relative to the support 9, by means of two primary connecting rods 20 mounted in rotation around the rear link bar 15 and with the device 3.

The frame 5 is also articulated at one end 21 before the sides 12, 13, relative to the support 9, by means of two secondary connecting rods 22, mounted in rotation with two fixing plates 23, integral with the slides 11 .

Such an arrangement allows the frame 5 to collapse with each change in the road behavior of the vehicle 1. The occupant exerting a vertical point load on the seat 2, specifically on the seat 6 and its base, the device 3 collects this charge.

The device 3 comprises two cassettes 24 mounted on the rails 10 by means of plates 25.

As illustrated in FIG. 5, each cassette 24 comprises a base 26 mounted with a cover 27, so as to form an enclave, the base 26 being secured to the cover for example by means of screws 28.

The base 26 and the cover 27 are hollowed out with a first groove 29 in which slides an axis 30, between a high position and a low position, this axis 30 being mounted in rotation with the primary connecting rod 20, and the connecting rod 20 primary being dug with a hole 31 allowing the mounting of the axis 30.

Thus, when the frame 5 collapses, the primary connecting rods 20 rotate around the rear link bar 15 and the axis 30 slides in the first groove 29.

Each cassette 24 comprises a leaf spring 32 having a first section 33 wound around an anchor pin 34, the anchor pin 34 being integral with the base 26. The leaf spring 32 makes it possible to dampen the rotation of the axis 30 and makes it possible to push back the axis 30 to move the armature 5 from a load position to its initial position.

The leaf spring 32 comprises a second section 35 extending the first section 33 and being supported on the axis 30.

The first section 33 and the second section 35 form a V of angle A. The value of the angle A defines the stiffness of the leaf spring 32. The stiffer the leaf spring 32, the more effective the damping of the armature. The angle A0 (visible in FIG. 8) corresponds to the least stiffness of the device 3.

The first section 33 of the leaf spring 32 bears against a roller 36.

The roller 36 slides in a second groove 37, hollowed out in the base 26 and the cover 27 of each cassette 24. The roller 36 advantageously allows the device 3 to be adapted to the size and weight of the passenger seated in seat 2.

Indeed, the roller 36 slides between two positions:

a high position, associated with a seat 2 moved back sufficiently for the installation of a large passenger, the slides 11 allowing the longitudinal position of the seat to be moved back,

- A low position, associated with a seat 2 advanced sufficiently to the installation of a small passenger, the slides 11 for advancing the longitudinal position of the seat.

As illustrated in Figure 6, the frame 5 is in the initial position, the axis 30 is in the high position. The seat 2 is in the retracted position, the seat 2 has been moved longitudinally in this position by means of the slides 11, as shown by the horizontal black arrow.

Advantageously, a stirrup 38 is integral with the roller 36, and the stirrup 38 is mounted in rotation with the device 3, and more particularly with the base 26 and the cover 27 of the cassette 24, both hollowed out with a hole in which a pivot 39 is mounted for rotation, integral with the stirrup 38.

The stirrup 38 allows to adjust the stiffness of the leaf spring 32. Indeed, the bracket 38 has a U shape comprising two uprights 40 and a dish 41, the dish 41 having an opening 42 allowing the mounting of an elastic member such as a spring 43 with turns, for example .

The coil spring 43 is attached to both the stirrup 38 and the rail 10 by means of a point 44 of attachment extending from the rail 10. The coil spring 43 is extendable at an elongation minimum to maximum elongation.

Thus, when the seat 2 is moved back, the coil spring 43 will tension and reach its maximum elongation, the caliper 38 will rotate and the roller 36 will slide in the second groove 37 to lock in the high position .

The roller 36 thus exerts a maximum compressive force on the first section 33 of the leaf spring 32, thanks to the tension of the coil spring 43, only a certain weight (for example 90 kg or more) of a passenger sitting on the seat 2 would lower the second section 35 of the leaf spring 32.

In this configuration of the device 3, the two sections 33, 35 of the leaf spring 32 form an angle A1, the angle A1 being less than the angle A0.

As illustrated in Figure 7, the frame 5 is in a loading position, the axis 30 is in the low position, the seat 2 has collapsed, as indicated by the white vertical arrow, the seat 2 is in the retracted position, as in FIG. 5.

A large passenger and a sufficiently high weight allowed to pass the frame 5 in a load position, the axis 30 is thus passed in the low position in the first groove 29, as indicated the black circular arrow.

In this configuration of the device 3, the two sections 33, 35 of the leaf spring 32 form an angle A2, the angle A2 being less than the angle A1. This difference in stiffness between the two positions of the frame 5 allows the leaf spring 32 to accompany the rotation of the axis 30, when passing from a loaded position to the initial position of the frame 5.

As illustrated in Figure 8, the frame 5 is in the initial position, the axis 30 is in the high position. The seat 2 is in the advanced position, the seat 2 has been moved longitudinally in this position by means of the slides 11, as shown by the horizontal black arrow.

In this advanced position of the seat 2, the coil spring 43 is relaxed and has reached its minimum elongation, thus the roller 36 has slid in the low position in the second groove 37.

The roller 36 thus exerts a minimum compression force on the first section 33 of the leaf spring 32, a less significant weight (for example 50 kg or more) of a passenger seated on the seat 2 would make it possible to lower the second section 35 of leaf spring 32. In this configuration of the device 3, the two sections 33, 35 of the leaf spring 32 form the angle A0.

As illustrated in Figure 9, the frame 5 is in a load position, the axis 30 is in the low position, the seat 2 has collapsed, as indicated by the white vertical arrow, the seat 2 is in the advanced position, as in FIG. 8.

A passenger of small size and a sufficiently high weight made it possible to pass the frame 5 into a load position, the axis 30 is thus passed into the low position in the first groove, as shown in the black circular arrow.

In this configuration of the device 3, the two sections 33, 35 of the leaf spring 32 form an angle A3, the angle A3 being less than the angle A0, this difference in stiffness between the two positions of the frame 5 allows the leaf spring 32 to accompany the rotation of the axis 30 when passing from a loaded position to the initial position of the armature 5.

The device 3 described above has many advantages and in particular allows:

- to provide a compact cushioning solution for a seat for several types of vehicles, in particular automobiles;

- Limit the vibrations and noise generated by the road behavior of a vehicle, while preserving the mechanical components included in the device 3 from wear;

- to preserve or even improve the comfort of the occupants of a vehicle, in particular automobile;

- adapt the cushioning of a seat 2 to the size and weight of a passenger seated in seat 2.

Claims (7)

1. Device (3) for cushioning a seat (2) comprising a frame (5) movable relative to a support (9) comprising at least one rail (10) in which slides a slide (11), the device (3) comprising at least one leaf spring (32) disposed between the frame (5) and the support (9) so as to retain the movement of the frame (5), characterized in that the spring (32) blade comprises a first section (33) bearing against a roller (36) integral with a stirrup (38) rotatably mounted with the device (3), the stirrup (38) being attached to the rail (10) by means an elastic member such as a spring (43) with turns which can be extended according to a minimum elongation to a maximum elongation. 2. Device (3) according to claim 1, characterized in that the leaf spring (32) is contained in a cassette (24) fixed to a plate (25) integral with the slide (11). 3. Device (3) according to claim 2, characterized in that the frame (5) comprises an axis (30) sliding in a first groove (29) hollowed out in the cassette (24). 4. Device (3) according to claim 3, characterized in that the first section (33) of the leaf spring (32) is wound around a peg (34) for anchoring. 5. Device (3) according to any one of claims 3 or 4, characterized in that the leaf spring (32) comprises a second section (35) extending the first section (33) and being supported on the axis (30). 6. Device (3) according to any one of claims 2 to 5, characterized in that the cassette (24) is hollowed out with a second groove (37) in which the roller (36) slides between two positions - a high position, in which the elastic member such as a coil spring (43) is in maximum elongation, the seat (2) being in the retracted position, - A low position, in which the elastic member such as a coil spring (43) is in minimum elongation, the seat (2) being in the advanced position. 7. Seat (2) comprising a damping device (3) according to any one of the preceding claims. 8. Vehicle (1) comprising a seat (2) according to claim 7. 1/4