A cylinder propping system includes a sleeve and a locking member. The sleeve includes an outer wall that defines an inner cavity and a ledge. The inner cavity is sized to receive at least a portion of a cylinder assembly therein. A first end of the outer wall is configured to hingedly couple to one end of the cylinder assembly. The ledge is spaced apart from the first end. The locking member is sized to engage with the ledge, between the ledge and a cylinder housing of the cylinder assembly, to prevent movement of the cylinder housing in at least one direction along a central axis of the sleeve.

A jack includes a main body (14) with a cavity (18). A lifting cylinder (42) is supported on the main body and is extendable into the cavity. A lock (30, 34) is movably coupled to the main body. A spring (38) is coupled to the lock and biases the lock into the cavity. A cylinder (86) is coupled to the lock and biases the lock out of the cavity against the biasing force of the spring.

A floor jack locking assembly is presented. The locking assembly may include a locking pin used to mechanically lock out the jack at a specified lift height. The locking assembly may avoid the hydraulic lift cylinder being the only stabilizing component of the jack when supporting a significant load. The locking pin may be coupled to lifting link arms, avoiding the need to have the locking pin inserted into or through the lifting arm of the jack.

A floor jack locking assembly is presented. The locking assembly may include a locking pin used to mechanically lock out the jack at a specified lift height. The locking assembly may avoid the hydraulic lift cylinder being the only stabilizing component of the jack when supporting a significant load. The locking pin may be coupled to lifting link arms, avoiding the need to have the locking pin inserted into or through the lifting arm of the jack.

A cylinder propping system includes a sleeve and a locking member. The sleeve includes an outer wall that defines an inner cavity and a ledge. The inner cavity is sized to receive at least a portion of a cylinder assembly therein. A first end of the outer wall is configured to hingedly couple to one end of the cylinder assembly. The ledge is spaced apart from the first end. The locking member is sized to engage with the ledge, between the ledge and a cylinder housing of the cylinder assembly, to prevent movement of the cylinder housing in at least one direction along a central axis of the sleeve.

A collapsible hoisting device for use in the construction of large metal containers and to a removable accessory applicable thereto. It facilitates construction procedures by reducing project times and costs. The collapsible device includes a column (2) along which respective upper bodies (6) and lower bodies (7) that have been inserted into said column (2) move. The bodies (6, 7) are linked by an extendable means (8). The upper bodies (6) and lower bodies (7) have a corresponding mechanism to lock or attach (9) to the column (2), The column (2) is mounted so that it pivots with respect to a base (1) and the upper body (6) has a housing (609) suitable for the insertion of a removable, fingernail-shaped accessory (12).

Heavy equipment is attached to slings and lifted by rollers raised and lowered in a structure with four pillars. Rollers prevent torque and provide vertical vectors. Roller axle supports move along the pillars. Two gantry crane frames are joined by cross and truss beams. Hydraulic jacks and pneumatic locks are controlled and sensed movements are communicated to processors for each pillar. One master processor communicates with a remote control. Sensors check lock and hydraulic cylinder position and allow roller movements only when positions are correct and all processors agree.

A machine leveling pedestal incorporating a cylinder and piston defining an interior space, having a helically threaded outer surface, and having an upwardly facing land; a hydraulic fluid port opening the interior expansion space; a nut having a downwardly facing land and gear teeth, the nut being threadedly mounted over the helically threaded outer surface; a drive gear connected to the cylinder and piston for vertically slidably engaging the drive gear with the gear teeth, and, upon alternate rotations of the drive gear, rotating the nut about the cylinder and piston so that the nut vertically moves between a mechanical support position and a hydraulic support position, the upwardly and downwardly facing lands contacting each other upon movement to the mechanical support position, and the downwardly facing land displacing upwardly upon movement toward the hydraulic support position; and a motor connected to the drive gear.

A jack includes a main body (14) with a cavity (18). A lifting cylinder (42) is supported on the main body and is extendable into the cavity. A lock (30, 34) is movably coupled to the main body. A spring (38) is coupled to the lock and biases the lock into the cavity. A cylinder (86) is coupled to the lock and biases the lock out of the cavity against the biasing force of the spring.

A jack includes a main body with a cavity. A lifting cylinder is supported on the main body and is extendable into the cavity. A lock is movably coupled to the main body. A spring is coupled to the lock and biases the lock into the cavity. A cylinder is coupled to the lock and biases the lock out of the cavity against the biasing force of the spring.