초록 ▼

A platform positioned in a swimming pool has a slave hydraulic ram at each corner which raise and lower the platform. Each ram has a barrel attached to the platform and a piston rod which is supported on the bottom of the pool. There is a hydraulic motor for each slave ram. The hydraulic fluid in th

A platform positioned in a swimming pool has a slave hydraulic ram at each corner which raise and lower the platform. Each ram has a barrel attached to the platform and a piston rod which is supported on the bottom of the pool. There is a hydraulic motor for each slave ram. The hydraulic fluid in this system is water. Each hydraulic motor comprises a cylinder with a piston therein. Each time that the pistons of the motor cylinders are retracted make-up water flows into the system from a tank. The pistons of the motor cylinders are actuated in unison by a single main cylinder. The main cylinder is operated by hydraulic fluid from a hydraulic pump through a control valve.

대표청구항 ▼

In a lift for a swimming pool or the like comprising a body defining the pool and having water therein, said lift including a vertically moving platform within the pool which can be raised and lowered through the water in the pool, and power means to vertically move the platform in the pool, the imp

In a lift for a swimming pool or the like comprising a body defining the pool and having water therein, said lift including a vertically moving platform within the pool which can be raised and lowered through the water in the pool, and power means to vertically move the platform in the pool, the improvement wherein said power means comprises: a plurality comprising a given number of spaced hydraulic rams connected to the platform and body for vertically moving the platform, a corresponding number of positive displacement hydraulic motors, each hydraulic motor comprising a cylinder having a piston therein, conduit means connecting each respective motor with a respective ram so that each ram is actuated by a respective motor, motor actuating means connected to said hydraulic motors to actuate the same in unison, said rams, said motors and said conduit means forming a hydraulic system, hydraulic fluid in the hydraulic system, said hydraulic fluid being water compatible with the water in the pool, and means connected to said hydraulic system for automatically supplying make-up water to said system to replace loss of water therein, said make-up water supply means comprising water supply conduit means connected to the piston end of each cylinder so as to be in fluid communication with the system through the interior of thE cylinder only when the piston is withdrawn from the cylinder to its maximum extent, and water supply means connected to said water supply conduit means, said hydraulic rams being so connected to said platform and body that the platform is raised when the ram is extended and the platform is lowered when the ram is retracted.