An inflatable restraint device for the luggage space of a motor vehicle

Abstract: The restraint device (1) is fitted in the luggage space (10) of a motor vehicle, in an area just behind the backrest (12; 16, 18) of a rear seat (14). The device includes at least one inflatable tubular element (2) with a first end portion (2a) secured to the said back rest (12; 16, 18) and a second end portion (2b) secured to a side wall (22) of the luggage space (10) at a point (24) longitudinally to the rear of the back rest, coupled to a source of gas for inflation (3) to be activated in the event of the vehicle being in an impact. When inflated, the tubular element (2) is operable to dilate radially and to contract longitudinally in such a way that, in the event of an at least partially frontal impact, it is able to counter forwards movement of the backrest (12; 16, 18) and forwards movement towards the backrest by luggage and other items placed loose in the luggage space (10).

Description: The present invention relates to a restraint device for the luggage space of a motor vehicle arranged in an area behind the backrest of a rear seat (see, for example US-A-6 004 084, corresponding to the preamble of claim 1). In the case of a frontal impact, any items contained in the luggage space can hit the back of the said rear seat or seats. In the prior art, car seats immediately in front of the luggage space need to be made sufficiently robust and strong to be deformed only to a limited extent as a result of an impact from luggage or other items carried in the luggage space. The manufacture of seats to a good standard from this point of view is therefore expensive. One object of the present invention is to provide a restraint device which is able to alleviate the aforesaid problems which occur in the event of a vehicle being in a substantially frontal collision. This and other objects are achieved according to the invention by providing a restraint device having the characteristics claimed in the appended Claim 1. Further features of the invention are disclosed in the dependent claims. Further characteristics and advantages of the invention will become apparent from the detailed description which follows, carried out purely by way of non-limitative example and with reference to the appended drawings, in which: Figure 1 is a partial perspective view of the rear portion of a motor vehicle fitted with a restraint device according to the invention, shown in a deactivated state; and Figure 2 is a similar view to that of Figure 1 showing a device according to the invention in an activated condition. In Figure 1, the luggage space of a motor vehicle indicated by reference sign 10 is constituted by the space behind a backrest 12 of a rear seat 14 of a motor vehicle. In the embodiment shown by way of example, the backrest 12 is divided into two portions 16 and 18, which can be folded by pivoting about an axis, indicated 0-0. The luggage space 10 is delimited at the front by the rear surfaces of the backrests 16 and 18, at the bottom by a flat or floor surface 20 and at the sides by the side walls 22 of the motor vehicle, of which only one is visible in the drawings. In the embodiment illustrated, a restraint device, generally indicated 1, is associated with each portion 16 and 18 of the backrest 12 of the rear seat 14. Each restraint device 1 includes an inflatable tubular element 2 with a first end portion 2a secured to the associated backrest portion 16 or 18, and a second end portion 2b secured to the adjacent side wall 22, at a point 24 which is longitudinally behind the back rest. As seen in Figure 1, the inflatable tubular element 2 of each restraint device 1 is secured at an intermediate portion 2c to the bottom 20 (for example) of the luggage space 10 close to the pivoting axis O-O of the associated back rest. In particular, this intermediate portion 2c of the tubular element 2 is secured so as to be releasable on inflation of the said tubular element. In the deactivated or rest state shown in Figure 1, the tubular elements 2 associated with the backrest portions 16 and 18 do not impede the folding down of these latter. The end 2b of the tubular element 2 of each restraint element 1 is coupled to an inflating gas source 3, of a type known per se, such as the type used to inflate air bags, for example. Control means are associated with the inflation means, operable to activate the latter under certain predetermined conditions, which are detected by sensors and indicated that the vehicle has been in an at least partially frontal impact. The inflatable tubular element 2 of each restraint device 1 is made in such a way that, when it is inflated, it is able to dilate radially and to contract longitudinally. This tubular element is manufactured, for example, using a technique described in the document "ITS-A New Restraint System for Side Impact Protection", by Y. Gershon et al., SAE, Technical Paper Series, No. 961018, International Congress and Exposition, Detroit, Michigan, February 26-29 1996. In the event of the motor vehicle being involved in an at least partially frontal impact, the gas generator 3 of each restraint device 1 is activated and inflates the associated tubular element 2, as shown in Figure 2. As explained earlier, the tubular element 2 of a restraint device 1 is able, on inflation, to dilate radially and to contract longitudinally. On inflation, the intermediate portion 2c of each tubular element 2 is released, thereby taking on a rectilinear configuration and taking up a position in which it forms an angle with the longitudinal axis of the vehicle. Once inflated, since it has contracted longitudinally, the tubular element 2 of each restraint element is able, on the one hand, to counter the tendency of the associated backrest 16 and 18 to move forwards and, on the other, to brake or stop any movement towards the seat by luggage or other items placed loose in the luggage compartment 10. In an alternative arrangement to that described above with reference to Figure 1, the inflated tubular element 2 of each restraint element can be partially incorporated into an associated back rest, beneath the upholstery thereof, which would preferably include a weakened portion, intended to tear in the event of the said tubular element being inflated. In a similar way, the portion of the tubular element 2 between the secured portion 2c and the end 2b could be arranged beneath the cladding of the associated sidewall 2 of the passenger compartment.

Claims: A restraint device (1) for the luggage space (10) of a motor vehicle, fitted in an area just behind the backrest (12; 16, 18) of a rear seat (14), this device (1) comprising at least one inflatable element (2) coupled to a source of inflating gas (3) to be activated in the event of the vehicle being in an impact; this device (1) being characterised in that the said element (2) is tubular with a first end portion (2a) secured to the said backrest (12;16,18) and a second end portion (2b) secured to a side wall (22) of the said luggage space (10) at a point (24) longitudinally to the rear of the backrest, the said tubular element (2) being operable, when inflated, to dilate radially and to contract longitudinally whereby, in the event of the vehicle being involved in at least partially frontal impact, it can oppose forwards movement by the backrest (12; 16, 18) and movement towards the backrest by luggage or the like placed unrestrained in the said luggage space (10). A restraint device according to Claim 1, characterised in that the backrest (12; 16, 18) of the said seat (14) is pivotable about a substantially horizontal axis (O-O); the restraint device being characterised in that the inflatable tubular element (2) is releasably fixed at an intermediate portion (2c) thereof close to the pivoting axis (O-O) of said backrest (12; 16, 18). A restraint device according to Claim 1 or Claim 2, characterised in that the said inflatable tubular element (2) extends parallel to the backrest (12; 16, 18) of the said seat (14) beneath a tearable layer of the upholstery of the said seat. A restraint device according to any one of the preceding Claims, characterised in that the said inflatable tubular element (2) extends partially along a side wall (22) of the motor vehicle, beneath a tearable layer of the cladding of this side wall.

Inventors: ROSTI ROSSINI LORENZO, ROSTI ROSSINI, LORENZO
Applicants: FIAT AUTO SPA, FIAT AUTO S.P.A.
Application year: 2000
Main classification: B60N2
IPC codes: B60R21, B60N2