Abstract: A hydraulic device powered by a wave includes one or more posts secured on a sea floor, a float buoyant on the wave, a housing secured to the posts and having a slidable piston for separating the interior of the housing into two chambers. Four pipes are coupled to the chambers of the housing with four check valves, for allowing the fluid to be drawn into the chambers from two of the pipes and to be forced out of the chambers into the other pipes step by step in order to generate a hydraulic power or energy and for powering or actuating the other facilities.

Abstract: A cylinder lock includes an outer handle formed on an outside of a door having a tumbler lock formed in the outer handle, an inner handle formed on an inside of the door having an inner rotating knob formed in the inner handle, an actuator laterally formed in a central portion of the two handles for operatively pulling a latch bolt inwardly for opening the door from a door frame, an outer slide slidably mounted in the two handles which can be pushed inwardly upon a depression on the outer handle from outside the door to retract the actuator and the latch bolt for opening the door when the door is unlocked, and an inner slide slidably held in the two handles which can be pulled inwardly to retract the actuator and the latch bolt also for opening the door from inside the door.

Abstract: An automatic door closer includes: a casing having a primary and a secondary cylinder juxtapositionally formed in the casing for resiliently holding two pistons in the two cylinders filled with a hydraulic oil and partitioned with a wall formed with a main hole and a throttling hole for communicating the two cylinders, wherein each piston is normally urged by a tensioning spring towards the two holes in the casing, whereby upon an opening of the door, an upper piston is retracted to compress an upper spring in the primary cylinder to suck oil from the secondary cylinder to the primary cylinder and also to extend the lower piston and tension the lower spring for accelerating a door opening operation and saving the door-opening force; and a positioning device provided for temporarily keeping the door at its opened state by locking a positioning pin in a recess formed in the upper piston.

Abstract: An improved locking device of combination lock comprises a combination lock having toothed combination wheels, a three-way locking means formed with the shaft of the combination lock, a three-extension key and a rear locking pin normally poking into the key hole of the locking means to prevent from turning the combination lock for enhancing security.