Hold-down device for aircargo pallets

#1. Field of the Invention

#For common aircraft carrying cargo, the cargo is usually palletized onto standardized flat pallets and standardized containers bases.

#The present invention relates generally to systems to restrain cargo within airplanes and more specifically to cargo holddown devices used to lock standard cargo and container pallets in place within the aircraft. With greater particularity, this invention relates to pallet hold down systems which accommodate defective or distorted cargo pallet or cargo containers. Cargo pallets and cargo containers used in the aircraft industry must conform to government issued standards and regulations. My invention, therefore also relates to the compliance of cargo pallet and cargo container to these regulations. Here, cargo pallet and cargo container are terms used herein interchangeably.

#FIG. 1. illustrates a perspective view of the holddown device for aircargo pallets according to this invention in the closed position over a distorted pallet.

#FIG. 2. illustrates a partial perspective view of the holddown device for aircargo pallets in the open position while receiving a distorted pallet.

#FIG. 3. illustrates a partial perspective view of a typical cargo-bay with distorted outboard edges of a pallet, partially shown.

#With view of FIG. 1, my hold-down device for aircargo pallets shown generally as 1 has a base 2 and two sides 3 and 4 to define a bay 5. Both sides 3,4 are similarly constructed. The sides and base are permanently attached to the aircraft according to specifications of the aircraft design. In the industry, pallet rollers under the bays and within an aircraft (not shown) facilitate the movement of cargo pallets within the aircraft and into bays. These rollers and bay frames are not shown here since those details would distract from the features of my invention. The bay 5 is sized to receive a pallet 6 within the side walls 3 and 4 over the base 2.

#As can be seen in FIG. 3, present pallet restraining systems using vertical restraining lipped slots 21 longitudinally aligned along bay sides 20 are sized to receive properly sized outboard edges 9 on pallets. Distortions of the outboard edges 9 above tolerance may prevent the pallet from fully fitting within the bay 5 due to fixed size lipped slots 21. For example, in FIG. 3, a pallet 6 may have an distortion in area 22 on the outboard edge 9 where the magnitude of the distortion exceeds the opening of the lipped slot 21. In these cases, the pallet will not properly fit within the bay 5 until the cargo pallet 6 is replaced with one having less outboard edge distortion or to correct or remove the deformation area 22 of the outboard edge 9. These solutions are costly and time consuming.

#Instead of lips on the bay sides 21, with FIGS. 2 and 4 at hand, it can be seen that my invention uses a plurality of cams 10 mounted to the sides 3,4 at intervals directed interiorly of bay 5 as shown in FIG. 2. Each cam 10 has an upper circular portion 12 and a downward oriented elongated portion or tongue 13 of the cam 10. The upper portion of the cam 12 is circular with gears 11 along this portion 12, for reasons that will be explained below. A tire shaped shock absorbing bumper 30 can be attached near the end of the elongated portion of each cam 13. These bumpers 30 can be mounted on the cam to extend beyond the tongue 13 to rotate above the pallet as the pallet is introduced into the bay 5 according to the variations in size of the pallet. Each cam 10 is mounted to the walls 3 and 4 in a manner that permits the cam 10 to rotate around a pivot point 31 of the cam which is the center of the circle defined by the upper circular portion of the cam 10. As the cam 10 rotates about the pivot point 31 the upper circular upper portion 12 acts as a set of gears 11 while the downward extended portion of the cam 10, with bumper 30 moves up and down to allow varying clearance to the bottom of the base 2. FIG. 4 shows that the cam 10 is attached to the sides of the bay using a threaded pin 14 through a mounting hole 27, washer 24 and cam holddown nut 26 mounted through the pivot point 31 to the walls 3,4. The cam 10 may also be secured to the side 3,4 in any other way that will permit the cam 10 to freely rotate about pin 14, with or without roller bearings (not shown) to minimize friction.