Patent Description:
Currently, one of the major problems affecting aircraft fleets is the time and cost of door seal maintenance. This problem can be highly accentuated for military cargo aircraft where the ramp/door seals have relatively large perimetrical dimensions when compared with the seal dimensions required for passenger doors. Most of the conventional seals for such cargo aircraft doors are formed as an integral contiguous seamless structure which thereby requires the entire seal to be completely replaced in case of damage. Seal replacement for such cargo doors also sometimes requires the removal and reinstallation of the door, installing a new seal and gluing the new seal in the associated seal track. These issues associated with conventional aircraft cargo door seals can thereby in turn lead to high costs and aircraft grounding time that can affect mission readiness.

The issues noted above with respect to conventional integral contiguous seamless seal structures are due in large part to the difficulty of developing and providing a suitable joint that withstands disengagement without affecting the pressurization and/or entry of electromagnetic waves from high intensity radiated fields (HIRF) that may be found in military aircraft, especially such as military cargo aircraft.

It would therefore be highly desirable if non-integral seals with suitably configured lap joints could be provided that would in turn allow relatively greater dimensional cargo door seals to be more easily installed and/or replaced. It is towards providing such solutions that the embodiments disclosed herein are directed.

<CIT> discloses an elastomeric seal that provides a corner joint for a sealing assembly. The corner joint provides a three-way sealing effect useful in sealing a plurality of barrier parts to each other and to the surface on which they rest. A corner joint, having a corner seal and an end seal. The corner seal has a deformable, convexly curved outer surface with projections therefrom, which conforms to a concave surface on the end seal so that a water-tight seal is created when they are brought together. Elongate sealsand may be abutted against the corner seal and end seal so as to provide an inverted 'T'. The seal parts are received into channels in the objects to be sealed, and the surface on which they rest, thus providing a water-tight sealing effect.

<CIT> discloses a sealing connecting element, a sealing end piece and a seal. In practice different seals are known which are produced as three-dimensional structures and then given to the customer. In order to simplify the production of seals, it is provided that sealing connecting elements and/or sealing end pieces are to be produced as separate molded parts made of a thermoplastic elastomer and these molded parts to be connected, shortly before the installation of a seal, to sealing profile strips to form a complete seal.

<CIT> discloses an aircraft including a fuselage, an aircraft fuselage end cargo door, and a fuselage end cargo door mechanism. The aircraft fuselage end cargo door couples to the fuselage at a major joint line. The fuselage end cargo door mechanism including a hinge rotatably coupling an aircraft fuselage end cargo door to a fuselage, the hinge being coupled to both the aircraft fuselage end cargo door and the fuselage so that an axis of rotation of the aircraft fuselage end cargo door, defined by the hinge, relative to the fuselage is located forward of a major joint line between the aircraft fuselage end cargo door and the fuselage, wherein an uppermost portion of the major joint line comprises a joint line radius where a portion of the joint line radius formed by the aircraft fuselage end cargo door pivots within another portion of the joint line radius formed by the fuselage.

The invention is defined in the claims. Broadly, the embodiments disclosed herein are directed toward aircraft door seals, especially door seals for aircraft cargo doors that include non-integral partitioned door seal sections with each end of one section being joined together with an adjacent abutted end of another door seal section by a lap joint assembly. According to certain embodiments, therefore, aircraft door seals may be provided which include door seal sections having abutted ends establishing a seal junction, and a lap joint junction seal assembly to sealingly join the abutted ends of the door seal sections, wherein the lap joint junction seal assembly comprises (i) a lap joint member having a lap joint base and a lap joint shelf extending from the lap joint base and sealingly engaged with a lower surface of the door seal sections over the seal junction, and (ii) an interior support spigot inserted within the interior space of each of the door seal sections at the abutted ends thereof. Each of the door seal sections may be a hollow profiled door seal defining the interior space and formed of an elastomeric sealing material.

According to the invention, lap joint shelf that is arcuately shaped in conformity with the lower surface of the door seal sections. The interior support spigot will also preferable have a cross-sectional shape in conformity with a cross-sectional shape of the interior spaces of the door seal sections. Each of the lap joint member and the interior support spigot may be formed of an elastomeric seal material which is the same as or different from one another. The lap joint member may also be in the form of a one-piece structure which includes the lap joint base and the lap joint shelf.

The door seal sections may be provided with at least one door seal mounting bead which is adapted to being positioned within a concavely recessed mounting trough defined by the lap joint base. In certain embodiments, the door seal sections may include a pair of oppositely extending door seal mounting beads, wherein a lower one of the door seal mounting beads is positioned within the recessed mounting trough of the lap joint base. The lap joint base may itself include a lap joint mounting bead.

These and other aspects and advantages of the present invention will become more clear after careful consideration is given to the following detailed description of the preferred exemplary embodiments thereof.

The disclosed embodiments of the present invention will be better and more completely understood by referring to the following detailed description of exemplary non-limiting illustrative embodiments in conjunction with the drawings of which:.

Accompanying <FIG> shows an aft view of an exemplary military style cargo aircraft CA which includes oppositely hinged forward and aft cargo doors FCD and ACD, respectively, which when opened in the state shown will allow access to the interior cargo space CS of the cargo aircraft CA within the aircraft's fuselage CF. Each of the cargo doors FCD and ACD may be operably provided about its respective peripheral edge with a door seal in accordance with the embodiments described herein, so that when the doors FCD and ACD are closed, the cargo space within the fuselage CF may be pressurized. In the interests of clarity of presentation, the door seal <NUM> in accordance with an embodiment of the herein described invention is not shown in <FIG> but is depicted in <FIG> in relation to the aft cargo door AFD.

As shown in <FIG>, the door seal <NUM> is comprised of a plurality of individual door seal sections 10a-10d that are contiguously positioned in sequence about and fixed to the perimeter of the door AFD. Each of the seal sections 10a-10d is comprised of an elongate profiled tubular seal body formed of a suitable elastomeric material (e.g. a thermoplastic elastomer) that is compressible under pressure when the door AFD is closed to seal the same, yet is capable of resiliently expansion upon release of the pressure when the door AFD is opened. The abutting adjacent pairs of adjacent ends of the door seal sections 10a-10d will thus form respective door seal junctions 12a-12d. The door seal junction 12a is shown in greatly enlarged manner for clarity of presentation in accompanying <FIG> and is representative of the other seal junctions 12b-12d of the door seal <NUM>. Thus, the discussion below with respect to the seal sections 10a and 10b and the lap joint junction 12a formed at the abutting adjacent ends thereof will be representative of all other seal sections 10c and 10d and all other lap joint junctions 12b-12d.

As is perhaps more clearly shown in <FIG> and <FIG>, the seal section 10a is a one-piece (unitary) structure having a cross-sectional profile that is comprised of an extended seal flap portion 14a and a mounting base portion 14b. As shown in <FIG>, the seal flap portion 14a extends outwardly and sloped relative to the edge structures of the door AFD so as to be deflected toward such edge structures when the door is closed to seal the same. The seal flap portion 14a is also tubular, i.e., defines an interior space, in the general cross-sectional profile shape of the seal section 10a. The specific cross-sectional profile of the seal section 10a is not crucial provided that it serves the purpose of sealing the aircraft door when closed. That is, the interior space of the seal section 10a may be resiliently compressed somewhat while the seal flap portion 14a is resiliently deflected toward the edge structures of the door AFD when the door is closed so as to provide a sealing effect around the door's perimetrical edge.

The door seal junction 12a will further include a one-piece lap joint member <NUM> that includes an arcuate lap joint shelf 16a which is in sealing supporting contact with a lower surface of the seal flap portion 14a. The lap joint member <NUM> also includes a joint base 16b that defines a concavely recessed mounting trough 16b1 that is sized and configured to accept therein the a lower mounting bead 14b1 associated with the mounting base portion 14b of the seal section 10a. An upper mounting bead 14b2 of the mounting base portion 14b is compressively held against the perimetrical edge structures of the door AFD by an upper mounting clip 18a. The lower end of the joint base 16b includes a lap joint mounting bead 16b2 which is in turn received within a concavely recessed mounting trough 18b1 defined by the lower mounting clip 18b. The lap joint member <NUM> is most preferably formed of an elastomeric seal material so as to be flexibly deformed when the door AFD is closed yet possess sufficient resiliency to return to an undeformed state when the door AFD is opened.

Connection of the abutted ends of the seal sections 10a and 10b is provided by an interior support spigot <NUM> having a cross-sectional profile corresponding to the cross-sectional profile of the interior space of the seal sections 10a and 10b. The support spigot <NUM> has a lengthwise dimension to allow one lengthwise portion to be received within the hollow interior space of the seal section 10a and an opposite lengthwise portion to be received in the hollow interior space of the seal section 10b when the ends of the seal sections 10a, 10b are abutted against one another. Like the seal sections 10a, 10b, the support spigot <NUM> is formed of an elastomeric material is compressible under pressure when the door AFD is closed to seal the same, yet is capable of resiliently expansion upon release of the pressure when the door AFD is opened.

The lap joint assembly 12a may be assembled in the manner depicted in accompanying <FIG>. In this regard, a lengthwise portion of the support spigot <NUM> may be inserted into the hollow space of the seal section 10a so as to extend outwardly from the terminal end thereof. At this time, the mounting bead 14b1 of the seal section 10a may be positioned within the mounting trough 16b1 of the joint base <NUM>. The seal section 10b may then be sleeved over the exposed lengthwise extent of the support spigot <NUM> until the terminal ends of each seal section 10a, 10b are in abutting contact with one another. At this time, the mounting bead 14b1 of the seal section 10b may likewise be positioned within the mounting trough 16b1 of the joint base <NUM>. Although not shown, the mounting bead 16b2 of the lap joint member <NUM> may be positioned within the recessed mounting trough 18b1 of the lower mounting clip 18b. Thereafter, the mounting clip 18a may be installed so as to secure the lap joint assembly to the perimetrical edge of the door AFD.

Claim 1:
An aircraft door seal (<NUM>) comprising:
door seal sections (10a - 10d) defining an interior space and having abutted ends establishing a seal junction (12a); and
a lap joint junction seal assembly to sealingly join the abutted ends of the door seal sections, wherein the lap joint junction seal assembly comprises:
(i) a lap joint member (<NUM>) having a lap joint base (16b) and a lap joint shelf (16a) extending from the lap joint base (16b) and sealingly engaged with a lower surface of the door seal sections (10a - 10d) over the seal junction; and
(ii) an interior support spigot (<NUM>) inserted within the interior space of each of the door seal sections at the abutted ends thereof;
characterized in that the lap joint shelf (16a) is arcuately shaped in conformity with the lower surface of the door seal sections (10a - 10d).