(1) Field of the Invention
The invention relates to submarine launch systems for torpedoes, and the like, and is directed more particularly to a bladder assembly for retaining and discharging water under pressure.
(2) Description of the Prior Art
Launch systems utilizing elastomeric bladders or diaphragms are known. Such systems provide advantages of low cost, minimal moving hardware parts, and minimal signature, or noise, associated with a launch.
Two types of elastomeric members have been proposed. A first type constitutes a generally spherical bladder. Sea water is pumped into the bladder, causing the bladder to expand. When the pressurized sea water is ported to the aft end of a launch tube, the elastomeric bladder forces the water to eject a torpedo, or other body, out of the launch tube as the bladder returns to its unstretched configuration. The launch is effected by use of only one moving mechanical component in the system, namely a firing valve which ports the pressurized sea water to the launch tube aft end.
A second type of elastomeric member constitutes a diaphragm which in an unextended state is essentially planar in configuration. The diaphragm is distended by pumping sea water on one side thereof. When the pressurized sea water is ported to the launch tube, the diaphragm forces water to eject the torpedo., or the like, out of the launch tube.
The first type of elastomeric member is disclosed in U.S. Pat. No. 4,848,210, issued Jul. 18, 1989, in the name of Laurent C. Bissonnette, wherein an elastomeric bladder of generally spherical configuration is shown in a projectile launch system. In U.S. Pat. No. 5,200,572, issued Apr. 6, 1993, in the name of Laurent C. Bissonnette, et al, there is disclosed a variation in which the bladder is generally ellipsoidal in configuration. The second type of elastomeric member is disclosed in U.S. Pat. No. 5,231,241, issued Jul. 27, 1993, in the name of Laurent C. Bissonnette, wherein an elastomeric diaphragm is shown in a projectile launch system.
The spherical and ellipsoidal bladders are expensive to manufacture and require a relatively large volume of space, always at a premium in submarine vessels. The diaphragm may be manufactured relatively inexpensively and e ires substantially less space than the spherical bladder. However, the connection of the periphery of the diaphragm to a foundation places bending stresses on the diaphragm and on the foundation. It is difficult to predict how many cycles of operation a diaphragm can safely withstand.
It is, therefore, desirable to have available an elastomeric member requiring less space than the spherical or ellipsoidal bladder, and having a safe and secure means by which the member is fixed to its foundation.