Abstract: A plurality of support vertical extensions are attached to the rear surface or transom of a boat, or to a dock. Each support vertical extension has a horizontal member so that a dinghy or the like can be supported transversely to the boat or dock. The vertical extensions, and thus the horizontal members, are raised and lowered by at least one hydraulic cylinder driving each of the vertical extensions. The vertical extensions are preferably telescoping into fixed vertical support members.

Abstract: The roller construction of the invention affords a high degree of support and stability to the launching and recovery of personal watercraft by lowering and raising a cradle through the use of rollers, some of which are positioned above the cradle while others of which are positioned below the cradle--and wherein each roller bears against a side of a polygonal-shaped vertical post along which the cradle rides.

Abstract: A boat washing system is provided for use with a boat lift having a frame for supporting an boat and a drive mechanism for selectively raising the frame to lift the boat from the water and lowering the frame to lower the boat into the water. The washing system includes a sprayer assembly having a plurality of spray nozzles. The sprayer assembly is communicably connected to a source of water under pressure. The sprayer assembly is mounted to the frame of the boat lift such that the spray nozzles are directed at the hull of the boat supported on the frame. Water is introduced into the sprayer assembly and directed through the spray nozzles at the hull of the boat.

Abstract: A boat lift includes a vertical main post mounted on a dock, the lower end of the main post inserted into a body of water adjacent the dock and with the lower end spaced above the floor of the water. A frame includes an outer guide post having a base mounted on the water floor with an upper end above the water level; the frame connected by a single member to the main post. A platform unit for supporting a small boat is slidably connected at both ends to the main post and the guide post, and a cable and winch unit is interconnected among the foregoing elements for effecting a level lifting and lowering of the platform unit into and out of the water.

Abstract: This invention relates to an apparatus and method for transporting a boat and elevating the boat above a body of water utilizing a lightweight combination boat trailer and lift. A lightweight support frame carries the boat during transporting and elevating. Positioning members attached to the lightweight support frame position the boat upon the lightweight support frame in a detachable manner. Three adjustable support legs are adjustably secured to the lightweight support frame. A cable and winch assembly is utilized for elevating the lightweight support frame and is connected to the adjustable support legs to simultaneously move the adjustable support legs in the same direction. This enables the lightweight support frame to be elevated to carry the boat above the body of water or lowered to carry the boat into the body of water.

Abstract: A method of distributing the loads generated between a ship and a supporting dry dock which comprises a platform comprising a number of articulatedly joined sub platforms and connected for lifting/lowering by opposed pairs of hoist winches, comprises moving certain combinations of the sub platforms by activating appropriate hoist winches, so as to alter forces to portions of the ship's hull, which forces may be evenly distributed, or concentrated so as to change the shape of local portions of the ship, or bring into alignment hatches and their covers.

Abstract: A heavy duty low-profile watercraft lift (10) for lifting small watercraft into and out of the water adjacent to a dock (12). The lift (10) comprises a single heavy-duty column (22) having a winch (28) mounted on the top thereof for raising and lowering a carriage (26) that is engaged with a track (32) formed on the column (22). Adjustable arms (72) and rails (74) on the carriage (26) enable adjustment to fit a watercraft. Opening (108) allows a pin to be inserted therethrough to hold the carriage (26) in a raised position. The winch (28) can be mounted to any side of the column (22) to meet the needs of a particular installation. The lift (10) of the present invention provides a compact, efficient, and visually appealing dockside lift.

Abstract: The piston rod of a lift cylinder unit on a boat lift is selectively locked from extending or retracting by a locking mechanism having a clamping ring which is sleeved on the piston rod and is biased into locking position by a compression spring engaging a piston in a locking cylinder. This cylinder is selectively supplied with pressurized water to compress the spring and thereby release the clamping ring. Hydraulic lines extend to the lift cylinder and locking cylinder from a control manifold located adjacent the boat lift for remotely operating the lift and the locking mechanism.

Abstract: A load lifting device for small watercraft has a vertical post having a lower post portion extending downwardly in the water from the top of the dock and rigidly mounted thereto and having an upwardly extending rectilinear extension and a vertically moveable cradle cantilevered off the post with a winch at the top of the extension connected to the cradle for raising and lowering it; the upwardly extending extension of the post being mounted on the lower post portion for rotation relative thereto so that when the cradle is moved vertically to a position carried by the extension it may revolve with such extension to swing a watercraft carried by the cradle over the dock or the water as desired. A lock is provided for preventing the post and extension from rotating during transition of the cradle between the two.

Abstract: A boat lift that is collapsible into a plurality of segments for quick and convenient transportation and storage during the off-season. The boat lift comprises a frame and a boat-engaging carriage that is movable on the frame between an elevated position and a lowered position. The frame forms an inclined track upon which the carriage traverses and comprises two spaced siderails, and a front and rear brace member. The front brace member comprises two segments that are each pivotally attached to a respective siderail. The segments are selectively removable from one another to permit the segments to be folded back adjacent their respective siderails. The rear brace member is selectively removable from the siderails so that the frame member may be collapsed into three separate segments. The carriage is removable from the frame and may be collapsed in a similar manner.

Abstract: A boat lift is arranged to include spaced rectilinear frameworks having leg members splayed exteriorly of a first framework extending to the second framework. The legs may optionally include telescoping extensions, with the extensions and legs having foot plates for mounting the frameworks to a support surface. Flexible webs are mounted at opposed ends between the frameworks to position and lift a boat therebetween.

Abstract: Upwardly extending pivoting booms are supported on a rectangular base which is submerged in water. Watercraft supports on mounting arms are connected to the pivoting booms. A double-acting hydraulic cylinder attached between the rectangular base and pivoting booms swings the pivoting booms upwardly until they are braced by boom supports on the rectangular base at an angle over center. This raising of the pivoting booms lifts the mounting arms and watercraft supports to remove a craft from the water and disposes the booms, mounting arms, and craft in a stable, secure over center configuration. Actuation of the double-acting hydraulic cylinder in the opposite direction forces the booms back out of the over center position and lowers the craft into the water.

Abstract: A launching and lift assembly for small watercraft such as a jet ski comprises a skid cradle for seating the watercraft thereon for sliding movement off an end thereof. The skid cradle is mounted on a dock for rolling movement thereon forwardly over a launching edge thereof on a rear caster and on a pair of forward support rollers secured to the dock at its launching edge, for downward tilting of the skid cradle on the support rollers over the launching edge to cause the watercraft to slide downwardly off the tilted skid cradle and into the water when the skid cradle and seated watercraft are rolled forwardly on the dock to a position wherein their center of gravity is located forwardly of the support rollers.

Abstract: A method of assessing a ships weight so as to e.g. assist in its design and development, or to ascertain its actual center of gravity or its loaded state, comprises positioning the ship on a dry dock platform made up of a number of articulatedly joined sub platforms connected for lifting and lowering by hoist winches. The hoist winches include signal devices which signal the load each is supporting, to a computer and visual display unit which displays the loads. The computer computes e.g. the center of gravity or the ships weight, in the displacement of the center of gravity from its designed position, the information then being passed to the designer.

Abstract: A heavy duty low-profile watercraft lift (10) for lifting small watercraft into and out of the water adjacent to a dock (12). The lift (10) comprises a single heavy-duty column (22) having a winch (28) mounted on the top thereof for raising and lowering a carriage (26) that is engaged with a track (32) formed on the column (22). Adjustable arms (72) and rails (74) on the carriage (26) enable adjustment to fit a watercraft. Opening (108) allows a pin to be inserted therethrough to hold the carriage (26) in a raised position. The winch (28) can be mounted to any side of the column (22) to meet the needs of a particular installation. The lift (10) of the present invention provides a compact, efficient, and visually appealing dockside lift.

Abstract: A raising and lowering device is provided which may be mounted on a reference structure having a mounting surface. The raising and lowering device includes a pair of guide columns, each guide column having a load bearing mount fixedly secured thereto. A load bearing surface on each load bearing mount abuts the mounting surface on the reference structure. Each guide column also defines a cavity and a slot allowing access to the cavity.A support structure which bears the objects to be raised or lowered extends through the slots and into the cavity of each guide column. Roller assemblies, coupled to the support structure, are positioned within the cavity of each guide column to direct movement of the support structure along the guide columns. Cables connect to the support structure at one end and to a cable joint at the other end. The cable joint is movable using a single actuator, the support structure being evenly raised and lowered thereby.

Abstract: A boatlift including two floatation chambers operably engaged to a boat hull engaging means by a lifting means connected therebetween. The lifting means is adapted to raise and lower the boat hull engaging means with respect to the floatation chambers, which, in turn, is adapted to buoyantly support both the boat hull engaging means and the lifting means. The boat lift may be either connectable to a stationary object such as a dock, pier or seawall, or may be adapted to be trailerable by land vehicle.

Abstract: A floating boat lift for lifting and supporting a boat above the surface of a body of water. The device includes a lower pontoon base and two elongated upper pontoons positioned above the lower pontoon base and held spaced apart and generally parallel one to another by a rigid frame connected therebetween. The upper pontoons are laterally restrained and are controlledly movable vertically with respect to the lower pontoon base by a vertical actuator arrangement. The upper pontoons may be filled or emptied of water. When empty, the actuator arrangement extends in length so as to lift the upper pontoons from the water. A boat placed atop the frame is also lifted and held above the water as the upper pontoons are drained. When the upper pontoons are filled with water, the actuator arrangement compresses in length and the lower pontoon base submerges until the lower portions of the upper pontoons become submerged, at which point the boat may be floated onto or removed from the submerged frame.

Abstract: This invention comprises an improved system for raising and lowering an object, most usually a craft, from and into the water. This improved system includes a plurality of pistons, usually disposed at each corner of a rectangular frame, actuated by a remotely disposed valve system which is connected to a common water hose. The pistons are comprised of a pair of cylinders one portion of which is secured to a slip or float and the other portion of which is secured to the craft-supporting rectangular frame. When water is introduced into the system, the craft is raised from the water and when the fluid is evacuated from the system, the craft is lowered.

Abstract: A powered method and apparatus for raising and lowering a boat in a boat lift with quick connection to and use of the boat battery to power a DC electric motor on the lift. A method of converting a manual lift to a powered lift is provided. The lift drive has a tractive drive unit with a friction wheel and the motor and a reduction drive, a drive unit subframe, a drive unit mount adjustable on the frame of the lift, adjustment structure to locate the subframe in a desired position in any one of a variety of boat lifts and with respect to a variety of manually operable lift actuator wheels, structure to resiliently bias the friction wheel against the actuator wheel, structure to stably remove the friction wheel from the actuator wheel, a quick connector for connection to a boat battery, and a switch for selective control of motor operation and direction of rotation.

Abstract: An elongated operating cylinder has an internal piston assembly including axially spaced diametral disks. Such assembly is movable lengthwise in the internal cavity of the cylinder. A flexible force-transmitting component is connected to the piston assembly and extends axially of the cylinder through one of its ends. Introduction of fluid under pressure into the cylinder cavity tends to move the piston assembly axially so as to apply a pulling force to the flexible force-transmitting component, adapting the cylinder for use as a fluid-pressure actuator. Such fluid pressure actuator is particularly suited for use in lift apparatus where a compact, stationary frame has upright rails along which a lift carriage is movable. The lifting force preferably is provided by the flexible force-transmitting component of the actuator which can be routed by one or more pulleys. The lift apparatus can be mounted adjacent to a dock for lifting a small watercraft from the water.

Abstract: The present invention sets forth an hydraulically operated boat lift for lifting small boats upwardly out of a body of water by simultaneously supplying water pressure to four support posts connected to four corner portions of a lifting frame. Each of the corner posts comprises an hydraulic cylinder with the cylinder body connected to the lifting frame and moveable vertically on its downwardly extending piston rod which forms support legs for the lift.

Abstract: The invention comprises an improved system for raising, lowering and wet/dry storing of a craft supported thereon. This improvement includes pontoon means and structural frame means, respectively, for supporting said craft. The pontoon means and structural frame means are disposed for coactive movement one with respect to the other. The coactive operation of this system during the raising/lowering of the craft provides self-adjustability to the system. The amplitude of coactive movement of the pontoons/frame means can be limited so that the craft is not moved beyond its fully raised and lowered positions. This coactive movement and, more particularly, this limited coactive movement, is contrary to prior art boat lifts that include a fixed, immovable support framework in which only the craft lift is moved between respective raised and lowered positions.

Abstract: A device is provided for hoisting a boat on board a ship, even when this latter is moving, in which a ramp is provided coupled to the rear of the ship for pivoting about a transverse horizontal axis related to the ship, said ramp being adapted for supporting and smoothly guiding the boat between the water and the reception zone provided on board the ship and being for this purpose formed by an array of cables stretched over a V shaped cradle.

Abstract: A boat lift for a berth having permanently positioned piles in pairs spaced apart a distance sufficient to permit the boat to be berthed thereat to move between the paired piles while in the water includes a cradle having fore and aft transverse members upon which the boat is supported out of the water, a first pair of such piles equipped with first sheaves, a second pair of such piles with second sheaves, a third pair of such piles positioned between the first and second pairs adjacent the second second pair, first and second beams carried by the inside and outside piles of the second and third piles, motor driven winch drums supported by the first and second beams, third sheaves carried by the first and second beams, first inside and outside cables reeved respectively from the first and second drums via the first and second sheaves forward to the inside and outside piles of the first pair to lift the fore transverse member of the cradle, and second inside and outside cables reeved from the winch drums via t

Abstract: The present shiplift apparatus has a horizontal lift platform with eight lift points (four on each side along the length of the platform). Four lift motors are provided, each operating a first cable for lifting the platform at a lift point which is located toward the longitudinal, midpoint of the platform and a second cable for lifting the platform at a lift point near one end or the other of the platform. Each second cable is connected to a linear actuator for leveling up the platform independent of the lift motors.

Abstract: A hydraulic power and control system which includes a pump which is mounted n a sealed housing. The pump is mounted in the sealed housing along with a pilot operated power valve. The pump has an inlet within the housing for intaking oil therein and is connected to the pilot operated power valve for operating components in a functional system, such as a submersible docking apparatus. The pilot operated power valve discharges oil into the sealed housing and is connected to a control valve which is located exterior of the housing. The control valve will pilot operate the power valve and discharges oil within the sealed housing. The control valve may be mounted within a pressure casing which receives a reduced oil pressure from the pump within the sealed housing. The sealed housing may be pressure compensated to ambient so that the pressure casing is maintained at a specific pressure level above ambient.

Abstract: The hull has a pair of laterally spaced pontoons which are rigidly interconnected by beams which extend between them at a level low enough that a barge will float over them. An elevator with a lifting and lowering mechanism is mounted on the hull with sling or cradle-like lifting bars. The lifting bars have upstanding posts which are shaped, sized and spaced to fit in the stacking post sockets conventionally provided in the hull bottoms of LASH barges. In a lower condition of the elevator, a barge will float over the bars. In a raised condition of the elevator, workers may stand on the hull pontoon decks and work on the sides of the barge and work on the bottom of the barge from scaffolding hanging under the lifting bars. For working on conventional river barges (which are longer than LASH barges) the lifting devices may be used in pairs.

Abstract: A heavy submersible object is deployed from or retrieved to a floating vessel in rough water. The connection or release point is sufficiently far below the water surface that surface waves have little if any effect on the object. Deployment and retrieval are made to an arm which depends from the vessel and which has a variable stiffness connection, ranging from free-swinging to rigid, to the vessel. Deployment and retrieval are made with the arm free-swinging from the vessel so the arm has no motion due to pitch or roll of the vessel. In retrieval, the connection is progressively stiffened to rigid after the object has been connected to the arm, and the arm is then raised with the retrieved object.

Abstract: A ship's docking plant includes a floating platform, partly enclosing a vertically displaceable docking member, providing large working areas around the same, when in raised position. The docking member is retained in relation to the platform by a vertical guide means at the inward, transverse side of the docking member, said guide means permitting the docking member to obtain various angular positions with respect to a horizontal plane, in the longitudinal, as well as in the transverse direction. The docking member is, along its longitudinal sides, connected to the platform by means of reversible chain winches, permitting an adjustment of the position of the docking member in relation to a horizontal plane, when lowered down.