SAFETY DEVICE IN THE CARGO HOLD OF AN AIRCRAFT

Abstract: Security device in the cargo hold of an air-plane for preventing that goods stowed in the cargo hold which during unloading of the goods by means of a conveyor is fed towards a cargo hold opening in said cargo hold, during discharging by means of the conveyor is brought into clamping engagement against object which are permanently attached to or temporarily stowed underneath the ceiling of the cargo hold in the area of the cargo hold opening (2), e.g. a cargo hold hatch (1) which is hooked up underneath the ceiling. In the cargo hold, in front of the cargo hold opening (2) is movably disposed a transversally extending flap (4) having a shape which substantially covers the sectional profile of said objects permanently or temporarily protruding into the cargo hold from the cargo hold ceiling. At a certain predetermined movement in the discharge direction of the conveyor said flap (4) is adapted to interrupt the driving of said conveyor.

Description: SAFETY DEVICE IN THE CARGO HOLD OF AN AIR-CRAFT The present invention relates to a security de¬ vice in the cargo hold of an air-plane adapted to prevent that goods, which during unloading of the cargo by means of a conveyor disposed in the cargo hold is fed towards the cargo hold opening, is broght into clamping engagement against cargo hold equipment which during open position of the hatch of the cargo hold, is stowed above the opening of the cargo hold at the ceiling thereof, e.g. outer and inner cargo hold hatches, barrier walls and/or cargo netting. In order to facilitate loading, stowing and un¬ loading goods in the cargo hold of a air-plane the cargo holds are often provided with a cargo hold bottom designed as a conveyor on which the goods during loading is automatically fed towards the in¬ ner end of the cargo hold, and which during unload¬ ing of the cargo feeds said goods towards the cargo hold opening situated at one end of the cargo hold. The space of the cargo hold which is situated in the area of the cargo hold opening must be kept free from goods during air transportation so that the hatch of the cargo hold is not being blocked and its operation not obstructed. Due to this measures must be taken to prevent that goods during transport is being displaced and falls down into the space im¬ mediately inside the closed hatch of the cargo hold. In acoordance with the commonly used design this is obtained by means of an inner hatch or wall which is pivotably supported at the cargo hold ceiling and extending in the longitudinal direction of the cargo hold. When goods has been loaded into the cargo hold the inner hatch or wall is swung down to the floor of the cargo hold, thus forming a partition wall preventing transversal displacement of goods into the area of the cargo hold opening. The end of the lowered inner hatch or wall which faces the cargo hold, is further provided with a cargo netting or a resilient protective wall preventing goods from be ¬ ing displaced in the axial direction of the cargo hold and from falling down into the area adjacent the outer hatch of the cargo hold. In accordance with a commonly used design the 5 outer hatch of the cargo hold is opened by being swung in a direction upwards-inwards into the cargo hold and is secured at the underside of the ceiling of the cargo hold. Then the inner hatch or wall is also swung in a direction upwards towards the ceil¬ 0 ing of the cargo hold where it is being secured, the transverse cargo netting or the flexible protective wall being included in said movement and stowed to¬ gether with the inner and outer hatches of the cargo hold. During unloading of the cargo the outer hatch 5 as well as the inner hatch and netting are thus in stowed position adjacent to the ceiling of the cargo hold and protrude from this position some distance in the downwards direction. It has proved that dur¬ ing unloading of the cargo it may happen that goods which by means of the conveyor has been forwarded 0 towards the cargo hold opening might strike against the end portions of the stowed hatches and get caught. If the feeding action of the conveyor then continues, the hatches and their attachments might 3_5_ be subject to unwanted load which may cause damage, crack formation or fractural impressions in the hatches and their attachments or in the supporting constructions to which they are attached. The object of the present invention is to pro¬ vide a security device for preventing that such un¬ wanted power influence may arise during unloading of the goods. According to the invention this is obtained by means of a transversally extending flap which is pivotably suspended at the cargo hold ceiling and disposed ahead of the portion of the cargo hold equipment which faces the cargo hold, e.g. outer and inner upwardly tilted hatches which during loading operation are stowed under the ceilung of the cargo hold. The flap is adapted to influence a limit switch when being tilted a certain angle towards the stowed hatches, said limit switch thereby switching off the current supply to the driving unit of the cargo hold conveyor. Suitably the limit switch is connected with the electrical control panel situated at the cargo hold opening so that it will be pos¬ sible to restore current supply to the drive unit of the conveyor from the control panel, and if required to drive the conveyor in the opposite direction some distance and when the colliding packages have been restowed, again restarting the feeding out of the goods. Suitably the flap is made by a rigid but to a certain extent resilient material, so that a certain power impact is allowed without provoking activation of the limit switch. The form of the flap is to be chosen such that it substantially covers the sec¬ tional profile of the hatches stowed underneath the ceiling of the cargo hold and the downwardly depend¬ ing part of the cargo netting or cargo wall. The invention is illustrated on the appended drawings in which - fig 1 shows a transversal sectional view through the cargo hold of an air-plane in the area of the cargo hold opening and with the outer and in¬ ner hatch stowed underneath the ceiling of the cargo hold, having the flap according to the invention de¬ pending in front of the stowed hatches, - fig 2 illustrates the attachment of the flap to the ceiling of the cargo hold. The outer hatch of the cargo hold, schematical¬ ly shown in fig 1, is swingably suspended inside the cargo hold so that the outer hatch may be swung from closed position for closing the cargo hold opening 2 into the upper stowing position beneath the ceiling 5 of the cargo hold as shown by full lines in the figure. The inner hatch or wall 3 is swingably sus¬ pended in the ceiling 5 of the cargo hold and may be swung between the position shown by broken lines and the stowing position beneath the stowed outer hatch 1 as shown by a full line. The flap 4 is swingably suspended in the ceiling 5 of the cargo hold and ex¬ tends in the transversal direction of the cargo hold at a distance ahead of the stowed hatches 1 and 2. The design of flap 4 is such that when being swung a certain angle towards the hatches 1 and 2, it actu¬ ates a limit switch, not shown, which after activa¬ tion switches off the supply of current to the cargo conveyor disposed at the bottom of the cargo hold and not shown in the figure. The flap 4 is made of a relatively rigid material which, however, is resil¬ ient to a certain extent, so that a certain deflec¬ tion of the flap is permitted without actuating the limit switch. The flap 4 is suitably made from lami¬ nated plastic material. Goods which is stowed in the cargo hold in the vicinity of the ceiling of the cargo hold will thus during discharging at first hit the flap 4, which after being swung a certain angle in the direction towards the stowed hatches 1 and 2 will shut off the discharge of goods, so that a required restowing of the respective parcels can be carried out. In the described embodiment in accordance with the invention, the cargo hold is provided with a hatch of the inwardly swingable type. The invention may, however, to the same extent be used in cargo holds having other types of hatch arrangement, e.g. including an outwardly swingable hatch of the cargo hold. Also in case of an outwardly swingable hatch the cargo hold must include an arrangement to pre¬ vent that the cargo, during the flight, will drop into the space immediately inside the hatch and thus blocking the operation thereof. The intemediate walls, protection nets etc which are used for this purpose, are being stowed underneath the ceiling of the cargo hold during unloading of the cargo, thus protruding a certain distance in the downward direc¬ tion from the ceiling of the cargo hold. Other equipment details, such as attachment fittings, which protrude in a direction downwards from the ceiling of the roof in the area at the cargo hold opening, may also result in a risk of goods being stuck during discharging. By means of the device ac¬ cording to the invention this risk is thus avoided no matter of type of arrangement of the cargo hold hatch and no matter which type of cargo hold equip¬ ment protruding in a direction downwards from the ceiling of the cargo hold and involves a risk for collision with the goods during discharging by means of a conveyor.

Claims: CLAIMS 1. Security device in the cargo hold of an air¬ plane for preventing that goods which is stowed in the cargo hold and during unloading of the cargo by means of a conveyor is fed towards a cargo hold opening (2) arranged in the cargo hold, during the feeding by means of the conveyor is brought into clamping engagement against objects, which are per¬ manently attached to or temporarily stowed beneath the ceiling (5) of the cargo hold in the area of the cargo hold opening (2) , e.g. a hatch (1) of the cargo hold which has been hooked underneath the ceiling, c h a r a c t e r i z e d by a trans- versally extending flap (4) which is movable in the cargo hold, said flap being disposed in front of the cargo hold opening (2) as seen in the discharge direction of the conveyor, said flap having a shape which substantially covers the sectional profile of said permanently or temporarily object protruding from the cargo hold ceiling into the carge hold, said flap (4) , at a certain predetermined movement in the discharge direction of the conveyor being adapted to interrupt the driving of said conveyor. 2. Security device as claimed in claim 1, c h a r a c t e r i z e d in that the flap (4) is pivotably supported at the ceiling (5) of the cargo hold ahead of the cargo hold opening (2) , as seen in the forwarding direction of the conveyor, and at a certain predetermined tilting in the discharge di¬ rection of the conveyor adapted to interrupt the driving of said conveyor. 3. Security device as claimed in claims 1 or 2, c h a r a c t e r i z e d in that the flap (4) , after a predetermined movement in the discharge di- rection of the conveyor, is adapted to actuate a switch for interrupting the supply of current to an electrical driving device of the conveyor. 4. Security device as claimed in claim 3, 5 c h a r a c t e r i z e d in that the switch is electrically connected with a control panel disposed at the cargo hold opening (2) , so that supply of current to the drive unit of the conveyor may be re¬ stored from said control panel. Q 5. Security device as claimed in any of the pre- ceeding claims, c h a r a c t e r i z e d in that the flap (4) is designed from a rigid , but to a certain degree resilient material, so that a certain power actuation on the flap is permitted without the 5 switch being activated. 0 5 0 5

Inventors: HELMNER ANDERS FREDRIK GUNNAR, HELMNER, ANDERS, FREDRIK, GUNNAR
Applicants: SCANDINAVIAN BELLYLOADING, SCANDINAVIAN BELLYLOADING COMPANY AB
Application year: 1989
Main classification: B64D9
IPC codes: B64D9