Abstract: Techniques are disclosed for systems and methods to provide accurate and reliable compact sonar systems for mobile structures. A modular sonar system includes one or more sonar transducer assemblies and at least two transducer modules disposed substantially within the sonar transducer assemblies. Each transducer module includes a transducer element and a module frame. The module frame is configured to support the transducer element, to physically couple to other transducer modules, and/or to physically couple to a sonar transducer assembly to secure the transducer module. The system may additionally include an actuator configured to adjust an orientation of the transducer module. Resulting sonar data and/or imagery may be displayed to a user and/or used to adjust a steering actuator, a propulsion system thrust, and/or other operational systems of the mobile structure.

Abstract: A closure for a fuel tank filler pipe comprises a body carrying a seal at one end for engagement with an outer end of the filler pipe, an outer cover, and a latch member at the other end of the body coupled to the cover and having latching projections for engagement with complementary formations on the filler pipe. A spring biases the latch member towards the outer cover so as to urge the seal into engagement with the end of the filler pipe when the latching projections on the latch member are in engagement with the complementary formations on the filler pipe. The connection between the latch member and the outer cover allows a predetermined range of angular movement of the outer cover relative to the latch member in the unlocking direction before unlocking commences.

Abstract: A closure for the filler pipe of a tank, comprises a gasket mounted in a gasket housing and arranged to engage with a flange on an end of a filler pipe, a cap stem coupled to the gasket housing for relative angular movement about the axis of the filler pipe and having a central portion adapted to project into the filler pipe. A clamp ring carries a pair of clamping lugs adapted to pass through cut-outs in the flange and, after angular movement, to engage under the flange. A spring acts between the stem and the clamp ring to urge the clamping lugs into engagement with the flange. A cam acts between the clamp ring and the gasket housing to hold the clamping lugs out of engagement with the flange until the clamp ring is at a predetermined orientation relative to the gasket housing. A locking ring couples the stem to the clamp ring.