Abstract: The present invention pertains to self-raising ocean platforms which possess multiple legs and multiple jacking mechanisms of the double rack and pinion type with opposite sets of teeth. In accordance with the invention, each double rack 4 contains sets of obliquely cut teeth, with at least one rigid component constituting a lateral thrust-block 7 being situated between the platform structure 2 and each platform leg 1, in such a manner that this arrangement provides force, c, which tends to press one portion of the platform leg 1 against the thrust-block 7, thereby ensuring constant positioning of the pinion teeth 5 in relation to the set of teeth located upon the rack 4.

Abstract: A platform lift with a ramp corresponding to the platform's thickness along one edge thereof, at least a part of which ramp is hinged along said edge and normally urged and locked in an upward barrier position to prevent objects from sliding or rolling off the platform when the platform is away from the ground. A single lever attached to the hinged ramp part depends below the platform and automatically releases the latch for maintaining the ramp as a barrier and then engages and moves the ramp part into its ramp-employing position as the lever contacts the ground. This lift platform and ramp part barrier mechanism is particularly adapted for wheelchair lifts on vehicles.

Abstract: The present invention applies to those auto-elevating marine platforms, as for deep-sea drilling and the like, outfitted with a number of legs and a number of associated jacking mechanisms of the rack and pinion type set with the rack's teeth in opposition, wherein a flexible coupling (5), the axis of compression of which is inclined, is placed between the support-framework (2), where the pinions (3) are mounted, and the main structure (1) of the platform in such a way that a relative freedom of movement between the support-framework (2) and the structure (1) is permitted. The intention is that the axis of compression of the flexible coupling (5) passes substantially directly through the instantaneous center of rotation of the upper part of the leg.

Abstract: A device for controlling the relative vertical movements between the bridge and the feet of a marine platform, including racks cut in uprights fixed to the feet, and locomotor units each comprising a frame equipped with pinions driven in rotation by motors and meshing with the racks. Each locomotor unit frame is attached by an articulation to a connecting rod which extends along the upright, and by a separate articulation to the bridge, and is associated with a mechanism for balancing the overturning torque set up by the force which the connecting rod transmits. The device is intended for a platform for the drilling of oil wells.

Abstract: A crane type lifting assembly for heavy loads employing two pairs of spacedly positioned frame mounted screws bridged by a balanced yoke type beam with each end of the beam guided between the screws.

Abstract: A lifting mechanism with a lifting platform, a lifting column supporting the platform, a threaded catch rod attached to the column, and an easily workable nut mounted on the rod and surrounded by a housing forming part of the platform. The housing engages the nut through a ball bearing and spring so that the nut rotates and moves up and down with the platform during normal operation. If the platform moves downward rapidly the spring is compressed and a projection on the housing engages the nut to stop downward movement of the platform.

Abstract: A system for making a "jack-up" rig with its jacked-up legs and hull rigid and fixed together by the use of "rack chock" elements which are designed to absorb the maximum axial chord loadings on the legs and transmit them directly into the hull. The "rack chock" elements are configured preferrably with a number of matching teeth for exact, in-line engagement with the legs' rack teeth, and are capable of being adjusted for vertical alignment and horizontal positioning to mate with the rack teeth position. By a series of screw jacks and/or secondary chocks, the "rack chock" elements provide rigid contact with both the legs and the hull structure and eliminate the requirement for the jack pinions to take the load (as is done in the prior art) in either jacked-up or ocean-tow dispositions.

Abstract: A safety device for load lifting and lowering apparatus of the kind comprising a pair of parallel spaced apart upright guide members of hollow section along each of which travels a runner mounted on a load carrier, a cable being connected to each runner to pull it upwardly along the guide member or lower it down the guide member, comprises pawls rotatably mounted on the runner and a block slidable relative to the pawl to which the cable is connected. Levers are pivotally mounted one on each pawl and one end of each lever is pivotally and slidably connected to the block. Springs urge the block towards the runner. Each pawl has a tapered edge and a roller which rests in normal use in a recess. In normal operation tension in the cable separates the block from the runner but when the tension is released, the springs urge the block towards the runner thereby rotating the levers and thereby moving the roller upwardly so that the pawls are jammed against the walls of the guide member.

Abstract: A method and apparatus for lifting a tower crane, and for supporting the tower crane when lifted, utilizes the existing structure of the tower's mast sections for connection of lifting and supporting apparatus. Hydraulic jacks lift threaded lifting rods, which extend down to a pair of lifting yokes by means of adjustable nuts positioned to engage lifting surfaces of the jacks from above. At the top of the stroke of the jack, a second set of nuts are spun down the threaded rods to a position engaging a stationary support surface from above, so that the jacks can then be lowered and the first set of nuts can be spun down and returned to their original position. A third set of nuts is positioned near the bottoms of the rods to provide a means for supporting the lifting yokes.

Abstract: A jacking assembly for a leg of a jackup offshore platform includes driving assembly and a movable carriage. The driving assembly includes a pair of counterrotating pinions spaced to receive a double-toothed gear rack of the carriage. The driving assembly is attached to the platform so that it can be entirely removed for reuse, if desired. The double-toothed gear rack is pivotally connected to a movable yoke at the upper end which yoke surrounds the leg. Surfaces of the double-edged gear rack are provided with stiffening members that cooperate with the driving assemblies to guide the gear rack during relative movement between the leg and the offshore platform. To selectively connect the carriage with the leg, the movable yoke is provided with a plurality of actuators having pins received by openings at preselected distances along the leg. A locking device is provided on the platform to engage other openings on the leg to fix the relative location of the platform and the leg while the carriage is repositioned.

Abstract: A trussed leg structure for use in jack-up mobile offshore platforms of the type that include a plurality of support legs extending into the water down to the ocean floor with jacking units engaging each leg to raise and lower the platform structure relative to the surface of the water. The leg structure disclosed includes a plurality of mutually parallel and laterally spaced apart column members rigidly interconnected to define a triangularly-shaped leg. The leg structure has only a single elongated rack carried on one of the column members to provide single point jacking of the leg. The rack comprises a flat, plate-like rack member having a set of rack teeth extending along each edge for meshed engagement with a separate one of a pair of pinions on a jacking unit. Two of the three column members are made of tubular pipe. The third column member, which carries the elongated rack, is an elongate rack plate oriented perpendicular to a plane defined by the first and second column members.

Abstract: In a method for erecting the jacket of a cable net cooling tower which has a center mast, which method includes hoisting the jacket by lifting forces produced by hoisting means located at the top of the center mast, the jacket is suspended from pulling members composed of groups of threaded steel rod units, each unit being composed of a succession of individual steel rods joined together at their ends by threaded sleeves, the lifting forces are transmitted to the steel rod units by setting elements detachably connected to the steel rods, and the uppermost individual steel rod of each unit is removed when it is no longer in force transmitting relation with the hoisting means.

Abstract: A jack device for supporting and raising grain bins of the type constructed from top to bottom. The jack has an A shaped frame and an outwardly inclined brace leg. Three fixed pulleys and a floating pulley receive a cable that may be taken up by a winch mounted on the frame. The floating pulley is equipped with a hook which engages the bin in a manner to hold it at an elevated position and to raise the bin as the cable is taken up by the winch. The multiple fixed pulley arrangement acts to distribute the forces over the frame to thereby increase the stability of the jack in handling large bins.

Abstract: A two-pillar, above floor elevating platform for vehicles having lift trucks disposed in each of the two pillars respectively. A three-phase AC motor in each pillar drives each lift truck vertically along the pillar. Apparatus which synchronizes the movement of the two lift trucks is located in a base platform upon which the two pillars are mounted. One of the motors may be disconnected when the torque necessary to lift the vehicle can be developed by the other motor. A one-phase to three-phase converter may be used to power the vehicle elevating platform in areas where only one-phase power is available.

Abstract: An apparatus for supporting and transporting gymnastic equipment such as uneven parallel bar assemblies, including a wheeled frame-like structure and lifting devices thereon having associated therewith members for engaging a bar portion of a device to be lifted and transported, the lifting devices being adjustable to raise the gymnastic equipment or the like off of the floor, support it in an elevated condition while it is being transported and stored, and lower it when it is desired to reinstall it for use.

Abstract: Boat jacks operable in pairs to lift a boat off a wheeled carrier, each jack resting on a "T"-shaped base and supported by a tripod, each jack being specially modified by providing a horizontal lifting member on the front of the jack component that is movable up or down by a cranking arm, each horizontal lifting member being lodgable in longitudinally extending side channels provided on the hull of a boat, each base being clear of the boat, and a connecting chain provided between the horizontal lifting members to furnish additional lifting support to the jacks and to prevent their lateral movement one away from the other.

Abstract: Mold dumping apparatus. Means are provided for dumping excess slip from a mold after desired wall thickness of greenware is obtained. Clamp structure is arranged on a first pair of uprights which latter are both vertically and pivotally movable on a pivot axis with respect to a second pair of uprights. Said second pair of uprights are supported rigidly on a base. The mold is received within said clamp structure and the mechanism operated to lift the first pair of uprights upwardly with respect to the second pair thereof. As same reaches a substantially predeterminable point near but above the point of the above-mentioned pivot axis, same becomes overbalanced and will automatically tip and dump the excess slip out from the mold. Any suitable receptacle may be provided for receiving said slip as it flows out of the mold.

Abstract: A lift device having a vertical column securable on a support surface. A support frame is movably secured along at least a portion of the column. A driveable drum is secured in an upper part of the column and a drive assembly, including a drive motor, is coupled to the drum. At least one cable is secured to the drum and the support frame and is of sufficient strength to displace the support frame and a load thereon along the column. In a preferred embodiment, there are two columns spaced apart, whereby a vehicle can be lifted from each side thereof.

Abstract: A gear axially drives a jack support element and is adapted to reciprocally move the same along a movement axis. A stop disposed adjacent an end limit of the element movement is adapted to collapse upon exertion of a predetermined force thereagainst whereby damage to the driving gear and driven support element is avoided.

Abstract: The lifting mechanisms of each of a plurality of columns of a vehicle hoist are synchronously driven by an endless member which may have its power source on one of the columns. A switch to energize and de-energize the power source has a control arm that is coupled, through a lost motion mechanism, to a trigger-like, normally inactive safety mechanism that is held cocked by a safety rod. A rotary idler carried by the safety rod is biased against the endless member in a direction to withdraw the rod from the safety mechanism in the event of a break in the endless member, releasing the trigger energy to effect shifting of the power source switch to the off position by overriding actuation of the lost motion coupling mechanism.

Abstract: In offshore platforms and the like of the type comprising a structure, such as a hull, and a plurality of upright legs for supporting the structure on the floor of a body of water, the invention provides an improved rack-and-pinion type jacking apparatus for connecting the structure to the legs in vertically adjustable fashion. For each leg, at least one dual rack bar is employed, the rack bar having two opposed sets of rack teeth each extending along a different one of the two edges of the bar. A jacking unit is mounted on the structure adjacent each rack bar and includes at least one pair of drive pinions with the pinions of the pair each meshed with a different one of the two sets of rack teeth, so that the two pinions are opposed across the rack bar. When the legs each comprise a number of tubular column members, one of the dual rack bars is provided for each of a plurality of the column members of each leg.