WO1990005665A1

WO1990005665A1 - Aircraft loading bridge

Info

Publication number: WO1990005665A1
Application number: PCT/AU1989/000503
Authority: WO
Inventors: Allan J. Wells
Original assignee: Rheem Australia Limited
Priority date: 1988-11-22
Filing date: 1989-11-21
Publication date: 1990-05-31

Abstract

A deformable contact member (16) forming an aircraft fuselage contacting lower edge of an entry vestibule of an aerobridge for providing access between an aircraft and an airport terminal, comprises a flexible bumper (12) of elastomeric material attached to a horizontally outward side of an elongate leaf spring (18). The deformable contact member (16) is attachable horizontally outwardly of a rigid structural member of a floor of the entry vestibule through flexure means (20, 22). The leaf spring (18) has high stiffness in the vertical direction and low stiffness in the horizontal direction. The deformable contact member (16) can contact the fuselage in sufficiently close conformity to provide a firm footing, sufficient air exclusion and minimum contact force between the deformable contact member (16) and the fuselage.

Description

AIR CRAFT LOADING BRIDGE

BACKGROUND

This invention relates to aircraft passenger loading bridges. Aircraft loading bridges have become very familiar at major city airports and provide personnel access to aircraft from elevated passenger lounges. The terminology used for aircraft loading bridges or parts of them includes aircraft vestibule and aerobridge, the latter term being adopted hereafter in this specification.

This invention particularly relates to details of the floor level aircraft-contacting surface of aerobridges and improvements thereto.

In the past the floor-level contactor between aerobridges and the aircraft has involved the use of a flexible elastomeric bumper. The requirements of a bumper when an aerobridge is mated to an aircraft include:-

a) the prevention of damage to, the aircraft by avoiding contact between it and any rigid part of the aerobridge;

b) the ability to conform in the face of some movement of the aircraft due to refuelling, loading and wind;

c) the ability to maintain a seal regardless of the curved profile of certain aircraft fuselages in the region of the entry door; and

d) the ability to maintain a seal between the aerobridge and the aircraft in a fire situation, to prevent smoke and flame entering either the aircraft or aerobridge.

The traditional design of bumper involves use of a "U" shaped fire rated flexible section of elastomeric material attached rigidly to the leading structural member of the vestibule floor. This requires deflection of the bumper material to cope with aircraft movement and fuselage curvature. However, the flexible elastomeric material must be rigid enough to allow passengers to walk on it without the passengers' feet becoming caught between the bridge and the aircraft. This required rigidity of the bumper in the vertical direction tends to be accompanied by a lack of desired flexibility and conf ormability as a result of forces applied in the horizontal direction. Thus the horizontal forces required to cause the bumper material to conform in the desired manner have be found to be high enough to be a cause of concern as regards the possibility of denting the aircraft fuselage skin.

Tests carried out on a standard design of bumper, in order to estimate the contact forces involved, when the bumper material was compressed to a reasonably workable deflection substantiated the cause for concern. The tests showed that for a reasonable deflection of 25 to 30mm the contact force was of the order of 8 to 10 Newtons per millimetre of bumper length and the pressure exerted was at least 100 kiloPascals (15 pounds per square inch). The significance of these figures is apparent when compared with what was considered acceptable: -

Aerobridge contracts let in 1987 were specifying a contact pressure less than 2.5 kPa; Boeing advised a maximum contact force of 12.5 lbs/inch (approximately 2 N/mm).

Not only were the loads a problem but the small deflection permitted at the centre of the bumper did not allow sufficient curvature to seal against most narrow-bodied aircraft. In practice a 50 to 70 mm gap was being left at each end of the bumper. This was of major concern to airport safety authorities. The high contact loads tended to assume secondary importance because aerobridges had been operated this way worldwide for quite some time despite recognition of the inadvisability of doing so.

The present invention has the object of providing full sealing contact against both wide and narrow-bodied aircraft without exceeding the recommended contact pressures and without reducing unacceptably the vertical rigidity required to not deform excessively downwardly under the weight of a person standing on the bumper.

SUMMARY

Accordingly, the invention consists of a deformable contact member forming an aircraft fuselage contacting lower edge of an entry vestibule of an aerobridge for providing access between an aircraft and an airport terminal, comprising a flexible bumper of elastomeric material attached to a horizontally outward side of an elongate leaf spring and wherein the deformable contact member is attachable horizontally outwardly of a rigid structural member of a floor of the entry vestibule; and wherein the deformable contact member comprises in combination the flexible bumper, the leaf spring, the leaf spring having high stiffness in the vertical direction and low stiffness in the horizontal direction and, flexure means joining the two end regions of the leaf spring to the structural member.

Preferably the flexure means comprises a pair of first supports attached adjacent to each end of the leaf spring and a pair of second supports fixed to the rigid structural member and location means allowing location and relative rotation about vertical axes of respectively co-operating pairs of first and second supports.

Preferably the location means comprises link means providing for both rotation and translation in a horizontal plane with respect to the first and second co-operating pairs of supports.

In one particularly preferred embodiment the link means comprises a pair of horizontally mounted bars pinned at each end of each bar to the respective cooperating pairs of supports and wherein additional spring means is provided between the deformable contact member and the rigid structural member.

Preferrably in the above embodiment the additional spring means comprise a pair of compression springs each one located adjacent one end of the co-operating pair of supports and wherein the springs are disposed to be compressed by horizontal movement of the deformable contact member toward the rigid structural member.

DESCRIPTION OF THE DRAWINGS

Without limiting the generality of the invention a particularly preferred embodiment and variations thereof is here described by way of example, with reference to the accompanying illustrations in which:-

Fig. 1 is a schematic representation of prior art rigid bumper shown in plan and end elevation views.

Fig. 2 is an embodiment of the present invention, shown schematically, in plan view.

Fig. 3 is a second embodiment of the invention, shown schematically, in plan view.

DETAILED DESCRIPTION

Referring to Fig. 1 a prior art aerobridge bumper 10 is shown in which a "U" shaped flexible elastomeric bumper 12 is fixed to a rigid support 14. The length of the bumper is slightly greater than the width of a commercial aircraft door.

Referring to Fig. 2, one embodiment of the invention is shown in which the deformable contact member 16 comprises a "U" shaped flexible bumper 12 as used in prior art arrangements. In the case of the present invention the bumper 12 is attached to a leaf spring 18. Fixed near each end of the leaf spring is a pair of pivot members 20 and 22. The pivot members comprise a pair of supports 24 and 26 attached rigidly to the leaf spring 18 and a pair of supports 28 and 30 attached to a rigid leading structural member 32 of the floor of the vestibule region of the aerobridge. A pair of pins 32 and 34 co-operatively locates each pivot pair, limiting upward or downward movement but allowing pivoting around the vertical (in use) axes. In use, leaf spring 18 bends due to the contact force applied by contact with the body (fuselage) of the aircraft. Due to deflection of the leaf spring and pivotal rotation around the longitudinal axes of pins 34 a desirable limitation of contact pressure commensurate with good sealing of the bridge with the aircraft opening is obtained.

A highly preferred embodiment of the invention is illustrated in Fig. 3. In Fig. 3, the deformable contact member 36 has bumper 12 attached horizontally outwardly (in use) of leaf spring 18.

As in Fig. 2, support pair 24 and 26 are attached to the rigid leading structural member 32 of the floor of the vestibule region of the aerobridge. Support members 24 and 26 are horizontally offset from support members 28 and 30 and inter-connected in a co-operative arrangement by means of a pair of horizontal arms 38 and 40, pinned by vertical pivot pins 42, 44, 46 and 48. A pair of compression springs 50 and 52 having suitable guides (not shown) interconnect each support 24 and 26 to a part of the rigid structure of the floor of the vestibule of the aerobridge. Preferably the leaf spring is assembled to the bumper with a controlled amount of curvature in the reverse direction to that curvature illustrated in Fig. 3. An amount of curvature of 20 to 30 mm at the centre over a length of 3.53 metres has been found preferable. The illustrated curvature of Fig. 3 is indicative of the shape the deformable contact member 36 in contact with an aircraft fuselage 54.

A suitable way of achieving the required curvature of the leaf spring and bumper is by fixing the rubber bumper to the leaf spring using brackets (not shown) fixed to the leaf spring at right angles to the plane of the leaf spring, to which is bolted each side of the width of the "U" shape forming, on assembly, the flexible bumper, the holes in the bumper material being formed after pre-bending the leaf spring as required with the brackets having pre-drilled holes so that the pre-bend is maintained by relative tension in the initial location of the flexible bumper to the leaf spring. A leaf spring made of 100mm x 10mm x 3530mm long SAE1074 cold rolled annealed spring steel has been found highly effective in experimental trials. The lexible contact member comprised of this and a "U" shaped rubber bumper, and pivot means as illustrated in Fig. 3, provided contact force less than 1 N/mm, in other words 10 to 12% of the force of the prior art bumper and about 50% below the maximum force specified by Boeing. The seal created along the bottom of the fuselage of a narrow-bodied aircraft was nevertheless complete and without gaps. The flexible contact member as shown in Fig. 3 may be limited in its travel inwardly and outwardly from the fuselage by a fixed stop associated with the guide rods (not showa) associated with the compression springs 50 and 52. The guide rods limit the amount of outward travel of springs 50 and 52 and the amount of inward travel tending to compress the bumper and compression springs may be limited by a push rod (not shown) acting on a limit switch (not shown) which switches on or off the motor or effector tending to urge the aerobridge against the side of the aircraft.

The side walls and roof of the bridge are formed of a concertina like structure and are not shown as they form no part of the present invention.

In Fig. 3 the pivoting arrangement with coil springs may be replaced by a flexure means of equivalent ef ect, such as approximating a "Z" shape, which could, at each end, replace the two supports, horizontal bar, pivot pins and compression spring by a single leaf type spring having a high stiffness in the vertical direction and a low stiffness in the horizontal direction.

That and other variations to the above described illustrative examples obvious to one skilled in the art would fall within the scope of the invention as claimed in the following claims.

Claims

1. A deformable contact member forming an aircraft fuselage contacting lower edge of an entry vestibule of an aerobridge for providing access between an aircraft and an airport terminal, comprising a flexible bumper of elastomeric material attached to a horizontally outward side of an elongate leaf spring; and wherein the deformable contact member is attachable horizontally outwardly of a rigid structural member of a floor of the entry vestibule; and wherein the deformable contact member comprises in combination the flexible bumper, the leaf spring, the leaf spring having high stiffness in the vertical direction and low stiffness in the horizontal direction and, flexure means joining the two end regions of the leaf spring to the structural member.

2. A deformable contact member as claimed in claim 1 wherein the flexure means comprises a pair of first supports attached adjacent to each end of the leaf spring and a pair of second supports fixed to the rigid structural member and location means allowing location and relative rotation about vertical axes of respectively co-operating pairs of first and second supports.

3. A deformable contact member as claimed in either claim 1 or claim 2 wherein the location means comprises link means providing for both rotation and translation in a horizontal plane with respect to the first and second co-operating pairs of supports.

4. A deformable contact member as claimed in claim 3 wherein the link means comprises a pair of horizontally mounted bars pinned at each end of each bar to the respective co-operating pairs of supports and wherein additional spring means is provided between the deformable contact member and the rigid structural member.

5. A deformable contact member as claimed in claim 4 wherein the additional spring means comprise a pair of compression springs each one located adjacent one end of the co-operating pair of supports and wherein the springs are disposed to be compressed by horizontal movement of the deformable contact member towards the rigid structural member.

6. A deformable contact member substantially as described and illustrated by the accompanying Figures 2 and 3.