| 摘要 |
<p>With reference to (Fig. 1), an aircraft passenger seat (1) is mounted on a floor (2) of an aircraft and comprises a body support frame (3), and a pair of rear legs (4), and feet (6, 7) for attaching the frame (3) to the floor (2) so as to be pivotable about a substantially horizontal axis (8) towards and away from the floor (2). The seat (1) also comprises restraint means in the form of a telescopic device (9) for preventing the pivotable movement unless overridden by impact loadings applied to the seat of a predetermined magnitude. The device (9), which serves as a normally solid strut, is disposed between the support frame (3) and front blocks (27), and is secured thereto by pivotal connections (28, 29). Should an aircraft incorporating the seat (1) make a forced landing whereby the impact load applied to the seat in the direction (95) is up to, say, 9.0 g, the seat, with its occupant, will wish to rotate about axis (8) relative to the floor (2) and in the direction of arrow (96). However, frictional forces in the device (9), imposed by clamping rings (56, 57), resist such pivoting. Should an impact load applied to the seat (1) be, say, 12.0 g in magnitude, the device (9) is overridden by the excess load, thus causing the seat to pivot. This rotational or pivoting movement, indicated by arrow (96), causes the tubular member (40) (Fig. 2) of the device (9) to be forced downwardly, into the tubular member (41), so as to contract the device. As the member (40) is forced into the member (41), the rings (56, 57) apply a substantially uniform frictional gripping force on it which absorbs the excess energy, i.e. the 3.0 g difference between 9.0 g and 12.0 g imposed on the seat (1), as the centre of gravity of the seat and occupant is displaced forwardly. The device (9) is provided with means operable to apply a seat-restoring movement. The device (9) may be replaced by a rotary form of restraint means.</p> |
