Sealing structure

A seal (5) suitable for sealing a door (3) to an aircraft fuselage (1) and which also acts as a rain channel when the door (3) is open. In one embodiment the seal (5) is of unitary construction and made from high tear strength silicone rubber. It comprises a flange region (7) for attachment to the fuselage (1) and a hollow compressible bulb (8) which connects the flange (7) with a pair of sealing lips (9,10). The invention has the advantage of providing an effective seal for doors having uneven inner surfaces.

This invention relates to sealing structures, for aircraft doors for 
example, and particularly to seals which unfold to form a gutter for 
collecting rainwater when the door is open. 
Some types of aircraft door are reinforced in certain areas with a 
honeycomb structure thereby giving the door a non-uniform cross-section. 
It is an object of this invention to provide a seal which will accommodate 
such non-uniformities in the door to be sealed. 
The present invention therefore comprises a sealing structure for an 
aircraft consisting of a pliable sealing strip having a first part forming 
a flange for connection to an aircraft fuselage; 
a second part forming inner and outer lips for abutment against an inner 
face of an aircraft door; 
a third part defining a hollow region and connecting the first and second 
parts and whereby, when the door is open, a rain channel is formed between 
the outer lip and part of the flange. 
The invention has been found to provide adequate sealing for doors having 
uneven inner surfaces. (Such as doors with honeycomb reinforcements). 
A further advantage of this invention is that it has been found to provide 
adequate sealing for doors whose direction of closing changes as the 
door's inner surface makes initial contact with the inner and outer lips. 
The thickness of the flange may be varied along its length to accommodate 
any irregularities in the aircraft fuselage outer surface. 
Preferably the sealing strip is made from high tear strength silicone 
rubber. 
Preferably the strip is moulded in one piece after being extruded, and then 
it is cured. 
The invention is particularly useful for sealing access panels to 
electrical equipment bays where it is essential that rain water be 
prevented from running off the fuselage and onto equipment. In such cases 
the sealing strip is preferably fixed to the upper and side walls of the 
equipment bay.

In FIGS. 1 and 2 an aircraft fuselage 1 is cut away to form an equipment 
bay 2. A bay door 3 is attached to the fuselage 1 by two hinges (one of 
which is shown ghosted and given the reference numeral 4 in FIG. 2) 
Around the sides of the fuselage defining the bay 2 is secured a sealing 
strip 5 made from silicone rubber. The strip 5 is attached to the fuselage 
1 by a series of rivets 6 which perforate a part of the strip 5 forming a 
flange 7. The remainder of the strip 5 comprises a hollow compressible 
bulb 8 which connects the flange 7 with inner and outer lips 9 and 10. A 
rigid metal backing strip 11 is riveted onto that side of the flange 7 
remote from the fuselage 1. When the bay door 3 is closed (see FIG. 1) the 
bulb 8 is compressed against the backing strip 11 and the inner and outer 
lips 9 and 10 abut the door 3 to form a seal. The bulb 8 serves to give 
some strength to the inner lip 9 which in turn acts as a lever to cause 
the outer lip 10 to seal tightly against the door 3. 
When the door 3 is open (see FIG. 2) the bulb 8 opens up allowing the outer 
lip 10 to protrude outwards away from the fuselage 1. Thus the region `A` 
between the outer lip 10 and lower part of the flange 7 acts as a rain 
channel for rainwater running off the fuselage 1.