A transmission assembly for a lifting column is provided. The lifting column includes an inner tube. The transmission assembly includes a hollow spindle, a transmission screw, a sleeve sleeved over the hollow spindle, a guide tube limited in the sleeve, and an actuating device actuating the guide tube to rotate. The guide tube and the hollow spindle are synchronously rotatable and axially expandable and retractable relative to each other. The transmission screw and the hollow spindle are synchronously rotatable and are axially expandable and retractable relative to each other. The actuating device is disposed in the inner tube and securely mounted to an upper end of the sleeve. A lower end of the sleeve is securely connected with a first transmission nut that is threadedly-fitted with the hollow spindle, the first transmission nut is securely coupled to the inner tube, and the upper end of the sleeve is movably disposed.

A telescoping stabilization strut system generally comprising a fixturing pin system with accidental or inadvertent operation protection for providing stability and support between a bearing surface such as a ground surface and a load such as a vehicle, an aircraft, a machine, or a structure.

A telescoping stabilization strut system generally comprising a fixturing pin system with accidental or inadvertent operation protection for providing stability and support between a bearing surface such as a ground surface and a load such as a vehicle, an aircraft, a machine, or a structure.

A linear jack includes an outer tube, a high speed assembly comprising a first rotating member threadedly coupled to a first translating member, a low speed assembly comprising a second rotating member threadedly coupled to a second translating member, wherein the low speed assembly is coupled to and translates with the first translating member. At least a portion of the high speed assembly is slidable in the outer tube between a first position, wherein the high speed assembly is engaged with a shaft, and a second position, wherein the high speed assembly is disengaged from the shaft. A thread pitch of the high speed assembly is greater than a thread pitch of the low speed assembly.

A linear jack includes an outer tube, a high speed assembly comprising a first rotating member threadedly coupled to a first translating member, a low speed assembly comprising a second rotating member threadedly coupled to a second translating member, wherein the low speed assembly is coupled to and translates with the first translating member. At least a portion of the high speed assembly is slidable in the outer tube between a first position, wherein the high speed assembly is engaged with a shaft, and a second position, wherein the high speed assembly is disengaged from the shaft. A thread pitch of the high speed assembly is greater than a thread pitch of the low speed assembly.

A lifting mast includes a bottom layer component set, a first moving component set and a second moving component set. with the technical feature that plural balls are embedded between the screw hole of the first moving base of the first moving component set and the threaded section of the bottom linkage rod of the bottom layer component set and the technical feature that plural balls are embedded between the second moving base of the second moving component set and the threaded section of the hollow connecting rod of the first moving component set, when the hollow connecting rod of the first moving component set is screwed to the bottom linkage rod of the bottom layer component set and is linked by the rotation of the bottom linkage rod, it is smoother.

A lifting device includes a guide unit, a support unit and a lifting unit. The guide unit is extendable and retractable along a direction. The support unit is disposed in the guide unit and includes a securing connector fixed to a seat body and made of elastic material, a support tube connected to the securing connector, and a support member disposed on the support tube. The lifting unit includes a first rod-actuating screw member disposed on the support member and having a first threaded hole, and a threaded rod unit including a first threaded rod extending into the support tube and being threadedly engaged with the first threaded hole, such that the first threaded rod is rotatable by an external force and movable in the direction.

A lifting device includes a guide unit, a support unit and a lifting unit. The guide unit is extendable and retractable along a direction. The support unit is disposed in the guide unit and includes a securing connector fixed to a seat body and made of elastic material, a support tube connected to the securing connector, and a support member disposed on the support tube. The lifting unit includes a first rod-actuating screw member disposed on the support member and having a first threaded hole, and a threaded rod unit including a first threaded rod extending into the support tube and being threadedly engaged with the first threaded hole, such that the first threaded rod is rotatable by an external force and movable in the direction.

A lifting mast includes a bottom layer component set, a first moving component set and a second moving component set. with the technical feature that plural balls are embedded between the screw hole of the first moving base of the first moving component set and the threaded section of the bottom linkage rod of the bottom layer component set and the technical feature that plural balls are embedded between the second moving base of the second moving component set and the threaded section of the hollow connecting rod of the first moving component set, when the hollow connecting rod of the first moving component set is screwed to the bottom linkage rod of the bottom layer component set and is linked by the rotation of the bottom linkage rod, it is smoother.

A portable lifting jack has a drivable mechanism operating a jack shaft formed of telescoping lifting screws. A microprocessor controls power to selectively turn electric motor to drive the operating mechanism. An in-line current draw sensor senses electric load of the motor and communicates this to the microprocessor. One detected electrical load is an electric load spike indicative that the jack shaft has contacted a mechanical load. A potentiometer connected to the operating mechanism senses extended position of the telescoping lifting screws and communicates this position to the microprocessor, which is programmed to derive when snug contact is achieved with an encountered mechanical load and to pause operation of the electric motor. In a synchronized array of jacks, all are paused to await further operator input, which may be coordinated through a remote control.