Seat equipped with a damped-oscillation lower resting cushion

Abstract: A seat equipped with a damped-oscillation lower resting cushion (11) in which sad lower cushion (11) is housed inside an element shaped as a container tray (14), installed on the top of a base framework which connects said container-tray-shaped element (14) with, and constrains it to, the support plane, independently on the rear back element of the seat. At its front end, the container-tray-shaped element (14) is hinged to the base framework, ad at its rear end, i.e , the end facing the seat back, it is connected with the framework by means of damping means, which dampen the vertical oscillations thereof. Furthermore, an adjustment device is provided, which makes it possible the height to be adjusted of the rest position of the rear side of the container tray (14) and of the resting cushion.

Description: The present invention is concerned with a seat equipped with a damped-oscillation lower resting cushion. Seats, in particular seats for cars, trucks, tractors or special vehicles, are known in the art, which are equipped, in their overall structure, with oscillation damping means. Although they show high enough characteristics of comfort, such seats normally have outline dimensions which are by far larger than those of a normal car. Furthermore, in the seats known from the prior art adjustment and damping means are provided in the back element thereof or in the complete seat structure, but the bottom cushion was never equipped with any independent systems for the elimination of the oscillations arising during vehicle travelling. DE-A-3 000 433 shows a seat corresponding to the preamble of claim 1 wherein a container-tray-shaped element is connected with a framework by damping means at its rear end. The purpose of the instant invention is hence of providing a seat equipped with suitable elements or devices which make it possible to eliminate, or at least to reduce considerably the disturbances which are due to the vertical oscillations arising during the use of the vehicle and are transmitted to the same seat. This purpose according to the present invention is achieved by providing a seat with a damped-oscillation lower cushion according to claim 1. The structural and functional features and the advantages of a seat with a damped-oscillation lower resting cushion according to the present invention will be better understood from the following exemplifying, non-limitative disclosure made by referring to the hereto attached drawings, wherein: Figure 1 shows a schematic side view displaying the bottom resting cushion of a seat according to the present invention, in a first position of maximum lowering thereof; Figure 2 shows a view similar to the view of Figure 1, with the rear side of the cushion being in its lifted position; and Figure 3 shows a view at all similar to the view of Figure 1, with the front side of the resting cushion being raised, in a second position thereof. Referring to the figures, a seat, in particular a car seat, is essentially constituted by a lower resting cushion, generally indicated With the reference numeral 11, and a seat back, partially shown in 12, both of which are suitably constrained to an underlying support plane. In the herein depicted example, said elements are only constrained to said underlying support plane by means of fixed guides 13, which enable the whole seat to be moved backward and forward. In particular, the bottom resting cushion 11 of a seat according to the present invention comprises an element having the shape of a container tray 14, inside which the stuffed portion of the seat (not shown in the figures) is housed. Said element 14 is hinged at the front end 15 thereof, which has a bent shape, above/around a pivot 16 which makes part of the seat framework or structure. More precisely, the pivot 16 constitutes a cross element which performs the task of connecting the side shoulders 17 with each other. Said side shoulders 17 can rotate, at their other end, around a rotation axis 18 which is also used as the lower rotation axis for the seat back 12. Furthermore, each one of said shoulders 17 is connected on both sides with mobile side guides 19 by means of two levers 20, 21. One end of one (20) of said levers is articulated in 22 onto the same shoulders 17 and one end of the other lever is respectively articulated in 23 to the mobile guide 19, whilst the other ends of said two levers are hinged to each other in 24. A lifting device for lifting the container-tray-shaped element between the fully lowered position shown in Figure 1 and the raised position shown in Figure 3, which can be of a whatever type, and is not specifically shown, promotes the positioning of the front end of the resting cushion 11. The container-tray-shaped element 14 is connected, nearly at its other end, with the mobile guide 19 by means of interposed damping elements 25. In particular, in the herein illustrated case, said damping elements 25 consist of two gas springs. A free end 26 of the stem of said gas springs is hinged in 27 to the container-tray-shaped element 14, and the container cylinder 28 thereof is hinged in 29 to a first, free end of a bell crank 30. An intermediate portion of the bell crank 30 is hinged in 31 to the mobile guide 19, such that the bell crank 30 can rock relatively to the same mobile guide. The other end of said bell crank 30 is hinged in 32 to the end of a drive rod 33 of an actuator means, which causes said bell crank to oscillate. In the herein illustrated example, said actuator means is a small motor 34 which causes a nut screw (not shown in the figures) to revolve. In its turn, said revolving nut screw causes said drive rod 33 to shift, by interacting with an externally, complementarily threaded portion thereof. Thus, a seat equipped with the damped-oscillation bottom resting cushion according to the present invention is capable of damping the oscillation of the "cushion" unit relatively to the "seat" unit, and at the same time enables adjustment of the height of the rear side of the cushion. The movement of oscillation of the cushion takes place around the front cross pivot fastened to the base framework or to the shoulders of the seat, and said oscillation is controlled by the rear damping elements. In that way, the damping advantageously takes place at that portion of the cushion which is into contact with the seat back, onto which the weight of the person who occupies the seat rests. The presence of the adjustment of the hinging point relatively to the seat framework, of the damping elements enables the occupier of the seat to adjust the position of the rear portion of the cushion, under non-operating conditions, at the preselected height which he will regard as being the most comfortable.

Claims: Seat with a damped-oscillation lower cushion, in which said lower cushion (11) is housed inside an element shaped as a container tray (14) installed on the top of a base framework (17) of the seat which connects said container-tray-shaped element (14) with, and constrains it to, an underlying support plane, characterised in that at its front end (15) said container-tray-shaped element (14) is hinged to the base framework (17) and at its rear end, i.e. its end facing the seat back (12), said container-tray-shaped element (14) is connected with said base framework (17) by means of damping elements consisting of gas springs (25) which are independent from said seat back (12). Seat according to claim 1, characterized in that said damping elements (25) are hinged to said base framework (17), with the interposition of means (28, 30) for adjusting the height of the point of application of said damping elements (25). Seat according to claim 2, characterized in that said height adjustment means comprise an actuator means (28) which is constrained to a bell crank (30), fulcrumed (at 31) to said base framework (17) and bearing ends of said damping elements (25) hinged to an end thereof. Seat according to claim 1, characterized in that the end of said container-tray-shaped element (14) has a bent portion (15) hooked in a hinge-wise fashion to a pivot (16) which is installed on the front portion of said base framework (17). Seat according to claim 1, characterized in that said base framework (17) comprises mobile guides (19) sliding above fixed guides (13), wherein a lower end of said damping elements (25) is fastened to said mobile guides (19), with said container-tray-shaped element (14) being articulated and rocking at one of its ends relatively to side shoulders (17) which can be rotated at their other end around a revolution axis (18), which can be also used as the lower tilting pivot for a seat back (12). Seat according to claim 5, characterized in that said side shoulders (17) and said mobile guides (19) are articulatedly connected on both sides to a pair of levers (20, 21), which in turn are articulatedly connected with each other.

Inventors: RAFFAELE ANTONIO, VILLA EZIO, RAFFAELE, ANTONIO, VILLA, EZIO
Applicants: FIAT AUTO SPA, FIAT AUTO S.P.A.
Application year: 1990
Main classification: B60N2
IPC codes: B60N2