Abstract: A dual-frequency vibration-reduction apparatus includes a beam having a longitudinal axis and a transverse axis perpendicular to the longitudinal axis. An attachment mechanism mechanically couples a portion of the beam to a structure. One or more masses are attached to the beam such that the apparatus vibrates bi-modally at a primary frequency and a secondary frequency for reducing vibrations of the structure at the primary frequency and the secondary frequency. A first mode may be a bending mode of the apparatus, while a second mode is a torsion mode. The vibration reduction apparatus may be tuned such that the primary frequency substantially matches a blade-pass frequency of a propeller-driven aircraft and the secondary frequency substantially matches a harmonic of the blade-pass frequency. The vibration reduction apparatus includes a mounting mechanism for mounting to any structure requiring low-frequency vibration attenuation.

Abstract: Disclosed is a periscopic device for examining an eye of a person with an inwardly squinting eye (esotropia). The periscopic device includes a tube with two mirrors arranged at opposite ends of the tube. The mirrors are arranged so that when the person looks through the periscopic device with the inwardly squinting eye, the two mirrors deflect the line of sight of the person toward an object reflected in the second mirror. To account for the squint of the eye, either a base out prism can be used to deflect the line of sight toward the first mirror, or the two mirrors can be arranged non-parallel to each other. With the inwardly squinting eye focused on the reflected object, the other eye can be examined. Methods of using the periscopic device are also disclosed.

Abstract: A dynamic damper assembly may include a plurality of bodies arranged at predetermined intervals on an outer peripheral surface of a drive shaft, and an elastic body formed to surround each of the bodies and fixing each body to the drive shaft.

Abstract: A movement system for submarine-atmospheric interface devices comprises fixed guides integrally connected to a conning tower of a submarine, a lifting apparatus slidable in the fixed guides, at least one electric motor for driving the lifting apparatus and a motion transmission mechanism whereby motion is transmitted from the electric motor to the lifting apparatus and comprising flexible transmission means.

Abstract: A lifting apparatus for devices used for detection, observation, air intake or communication on a submarine comprises a first movable mounting unit and a second movable mounting unit equipped at the top of them with at least one detection or communication device and at least one actuator associated with the first movable mounting unit and/or with the second movable mounting unit to move them along a main direction of movement. The apparatus further comprises a supporting member extending along the main direction and interposed between the first movable mounting unit and the second movable mounting unit and also having a pair of guides, each extending along the main direction and slidably coupled to a respective movable mounting unit to guide its movement along the selfsame main direction.

Abstract: The support and guidance structure includes a support (14) equipped with means of guidance (24) in translation in a raising direction (Z) for at least two masts (12), delimiting a respective housing (22) for each of these masts (12), and means of fixation (29) of the support to a structural part (15) of the underwater vehicle. Each housing (22) is open, on substantially all planes perpendicular to the raising direction (Z), in a second direction (Y) perpendicular to this raising direction (Z).

Abstract: Apparatus for moving tubes (10) which are displaceable upon operation of an actuator (40) inside fixed guides (20) integral with the tower (1a) of submarines (1) and the like, said actuator (40) consisting of at least one pair of linear motors (41).

Abstract: Apparatus for moving supports carrying sensors displaceable inside fixed guides integral with the towers of submarines, and the like, upon operation of an actuator, the actuator consisting of an electric motor coupled to one end of a screw actuator on which a screw nut integral with a rod is movable, the entire assembly being contained inside a housing with seals, from which the free end of said rod protrudes for fastening to the tube. The housing can include a first bearing and a second bearing or bushing for supporting the rod and the screw actuator coaxially within the housing. The housing can include a top chamber above the first bearing and a bottom chamber below the first bearing. One or both of the chambers can be filled with lubricating oil to dissipate heat and/or dampen noise. The bottom chamber can house the motor and include a dielectric oil. The motor can be controlled by an electronic actuating system using an angular position transducer.

Abstract: An optical observation device is connected to an extendable and retractable snorkel tube for above-water observation during the snorkel travel (travel at periscope depth) of the submarine. The optical observation device is designed as a compact unit which consists of an optronics unit with a short-travel drive. The compact unit is assembled on the snorkel tube. At least one further compact unit is provided which comprises at least one communication arrangement with a short-travel drive, wherein this further compact unit is likewise provided on the snorkel tube.

Abstract: A mast for use on a submarine is disclosed. The shape of the mast includes a sharp leading edge. The leading edge widens to an angle greater than the maximum angle of angle of attack that the mast will experience during maneuvering. The shape produces a stagnation zone that minimizes flow separations at the bow wave and has a pressure coefficient that approaches zero such that wake signatures of the mast are reduced. The surface of the mast is roughened to be capable of producing a turbulent boundary layer of the mast further reducing wake signatures from the bow wake.

Abstract: A submarine mast simulator as part of a buoyant tow body having a hydrodynamically shaped shell. The mast simulator includes a rigid lower mast section and an inflatable upper mast section extendable from the tow body. A plurality of stabilizer fins extend radially from the tail of the tow body, the fins being actuated to cause the ascent and descent of the tow body. A pressure sensor is positioned on an outer surface of the tow body for detecting a depth of the tow body, and a motor with controller is housed within the tow body, the controller initiating extension of the mast simulator in response to a depth indication.

Abstract: A system and method provides automatic monitoring of data representing the onset of, or occurrence of fault conditions for a submarine mast system. The system is separately programmable and transparently operable with respect to the mast host system that controls mast functions. In a preferred embodiment, a plurality of sensors are in communication with a microprocessor system to record data by time and date of the event. The communication of data from the sensors to the microprocessor is electrically isolated from control signal communications to mast components, and the sensors are further individually opto-isolated. The microprocessor may selectively transfer data on a time-shared basis over host system communication lines to an independent memory collecting submarine fleet data, as an aid in fleet-wide maintenance decision making.

Abstract: The mast device for a submarine comprises a guiding means, a vertically traversable mast guided therein and information means which are provided at the mast upper end and which are in electrical interaction with the inside of the submarine for emitting and receiving information. The information means are arranged in a buoyant unit held on the mast upper end without connection to this. The buoyant unit is fastened to a flexible coupling means which may be let out and retracted and which is of the length essentially of the maximum desired observation depth of the submarine.

Abstract: A directional heat exchanger system dissipates heat generated by components contained within a thermally insulated antenna mounted atop a periscope be. A first wall of thermally conductive material has a first face and a second face with the first face being shaped to substantially contact an internal portion of the periscope tube. A plurality of ribs made from thermally conductive material are fixedly coupled to the second face. A second wall of thermally conductive material opposes the second face of the first wall and is in tangential contact with the ribs to form a fluid seal therewith. At least one channel is formed between the first and second walls. The end of each rib is offset from the end of adjacent ribs such that the channel defines a flow path having a first end and a second end. The components generating heat are thermally coupled to a heat pipe positioned partially in the antenna and partially in the periscope tube.

Abstract: In brief summary, the invention provides an unmanned undersea vehicle sys comprising a mother vehicle and a daughter unmanned undersea vehicle. The unmanned undersea vehicle has an erectable observation mast for obtaining environmental information. A communication link interconnects the mother vehicle and the unmanned undersea vehicle for transferring command information from the mother vehicle to the unmanned undersea vehicle and unmanned undersea vehicle status information from the unmanned undersea vehicle to the mother vehicle.

Abstract: A modular structure for supporting and guiding tubes slidable in the vertical direction and carrying sensing, reconnaissance and transmission equipment for submarine towers, a frame formed by uprights and walls, which are longitudinal and transverse defining vertical compartments inside which the tubes supporting the equipment are slidable. The frame is secured to only the hull of the submarine via horizontal base elements which are integral with the bottom ends of the uprights and can be secured to corresponding flanges fixed to the hull of the submarine.

Abstract: A range finding device and method for determining the distance between a merged submarine and a target above the surface having a first and second periscopes mounted on a submarine with a known separation. These periscopes are rotatable and extensible above the surface and can determine the bearing from each of the periscopes to the target. A computer receives the bearings from the first and second periscopes and uses the bearings with the known preset distance between the periscopes to calculate the distance between the submarine and the target.

Abstract: A positive-action device for bringing about the rotary movement of a hatch, as a result of the traversing stroke of a shaft moving axially within a fixed structure, particularly in submarine turrets, includes an actuating component integral with shaft and moving with the latter in a direction parallel to the longitudinal axis of the shaft, and an articulated kinematic mechanism the upper end of which is hinged to hatch with an interposed flexible safety device and the lower end of which is rotationally integral with a regulating component rotating around the axis of a fixed pivot, there being associated with the regulating component a mechanism of bistable type for reliably maintaining the settings corresponding to the open and closed positions of the hatch, and end-of-stroke devices.

Abstract: A submarine radar antenna mast extension, retraction and rotation mechanism comprises a ball drive screw attached to the mast with a ball drive nut threaded to the screw. A rotary tube surrounds the mast with the mast keyed for translation within the rotary tube and prevented from rotation with respect to the rotary tube. An outer tube surrounds the rotary tube and effects a static hull penetration seal with respect to the submarine. The rotary tube rotates within the outer tube, but is prevented from translation with respect thereto. A brake/indexing assembly geared to the rotary tube selectively releases the rotary tube for rotation or locks the rotary tube to an indexed position for extension and retraction. A single bi-directional hydraulic drive motor geared to the ball drive nut effects mast extension and retraction by applying the brake to prevent rotary tube rotation. The drive motor effects mast rotation by releasing the brake.

Abstract: A submarine periscope system has a mast head 7 with a casing 10 from which protrudes a shaft 16 carrying observation instruments which are protected by a housing 8. A seal arrangement 30 is provided at the interface between the casing 10 and shaft 16 which imposes low friction torque at water pressures within the operational depth range of the periscope system and permits the shaft 16 to rotate for azimuthal movement of the observation instruments. A rotary drive 14 is connected to the shaft 16 for this purpose. The seal arrangement 30 imposes high friction torque at water pressures outside the operational depth range of the periscope system and a water depth pressure valve disables the shaft rotary drive to provide integrity of the seal arrangement outside the operational depth range. The mast head 7 is telescopically extendable by a hoist device 13 and does not penetrate the hull 2 of the submarine 3.

Abstract: A submarine periscope of the non-hull penetrating type has an extendable hoist (11) secured at one end to the submarine hull (2) and at its other end carries a sensor pod (8). Pod (8) is rotatable by a motor (13) carried by the hoist (11) and is electrically connected to sensory signal output devices (34,35) inside the hull (2) by a flexible cable (24) penetrating hull (2) at a gland (21) to which is fitted a rotatable signal transmission device (19). Cable (24) terminates at slip rings (32) secured to the transmission device (19) inside the hull (2). The transmission device (19) is rotatable by a motor (29) and motors (13,29) are both controlled by a controller (30) arranged to provide for synchronous rotation of pod (8) and device (19).

Abstract: A vibration damping arrangement for a structural member including leaf springs extending horizontally from a vibration absorber body adapted to be attached to the structural member. A set of horizontal-vibration-absorbing leaf springs extends in one horizontal plane while a set of vertical-vibration-absorbing leaf springs extends in another horizontal plane. A weight is mounted on the distal end of each leaf spring. The relative positions of the leaf springs in their respective planes are staggered around a vertical axis.

Abstract: The invention relates to an apparatus for damping vibrational deflections of periscopes or other vessel devices, which periscopes or other vessel devices extend into an aqueous medium when in use. Particular uses for the damping apparatus include application to periscopes, antennas and the like, for submarines. The damping apparatus preferably comprises a damping mass suitably mounted on a periscope or other extended-in-use device by damping elements. The damping elements may include, for example, elastic springy elements having a high internal friction, friction dampers, and coil springs which dissipate vibrational energy. The damping mass moves in response to vibrations of the damped device, thereby functioning as a kinetic energy storing device. The damping elements interact with the movement of the damping mass and thereby function as potential energy storing means.

Abstract: A system for gating a computer to receive navigational information from the osition sensors of the periscope assembly of a submarine is disclosed. A first coil is connected as the load coil of an oscillator and is mounted in a stationary position on a submarine bulkhead. A second coil is secured to the periscope assembly and moves up and down with the periscope, in and out of magnetic coupling with the first coil. A third coil is secured to the periscope assembly and moves up and down with the periscope assembly. A fourth coil is secured to the rotatable periscope assembly and remains magnetically coupled to the third coil while the periscope is either rotated or moved up and down. A normally opened switch button on the periscope handle is electrically connected to the fourth coil. Depression of the switch button results in a load on the oscillator which is otherwise normally tuned to the same frequency as a second oscillator.

Abstract: Hoisting and lowering mechanism for a mast capable of axial and pivoting ement, comprising a jack housed at the lower part of the mast and fast to a suspension with respect to which the mast can pivot, the end of the rod of the jack being coupled through an anchoring point to the fixed parts situated beneath the mast. The invention is useful for the optronic mast or the periscopic surveillance antenna of a submarine.

Abstract: A submarine's mast and its protective closure are prevented from inadvertly damaging each other while deploying or retrieving the mast and while securing the closure. Interconnected logic circuitry electronically prevents an improper actuation sequence so that the mast and closure do not collide. Mechanical linkages and fail-safes susceptible to corrosion and damage are eliminated thereby permitting more reliable operation from circuitry safely stowed inside the submarine.

Abstract: Apparatus for protectively housing radiation transmitting or receiving eqment is provided with a window in the form of a spherical segment, which is formed of material transmissive to radiation of the frequencies of the equipment, and which has a seating surface. A mounting for providing forces to support the window and to resist external pressure applied thereto has a bearing surface, and a heated bearing gasket abutts both the bearing and seating surfaces. The gasket is provided for resisting wear between the bearing and seating surfaces, and also for transferring selected amounts of heat to the window. A heat regulator is coupled between the window and the gasket to control the amount of heat transferred to the window by the gasket, and structure is provided for continuously joining the window, the mounting and the gasket.

Abstract: In a housing which is transparent to light of selected wavelength, a hypemispherical window of selected dimensions is formed of material which is transparent to light of the selected wavelength, the window having a seating surface. The window is supported by a mounting means, which has a bearing surface in abutting relationship with the seating surface of the window, and a compressible retaining means adjacent to the window and to the mounting means retains the window in immovable relationship with the mounting means, while sealing the window against external and internal pressures thereupon.