| 摘要 |
A hydraulically powered door or window opening and closing mechanism comprising an actuator (5) having a cylinder with a movable piston (13) therein and an arm (8) connected thereto for attachment to the door or window to be opened or closed. A mains or closed, pressurised water supply (35) is connected to first and second two-way solenoid valves (16,17) by supply pipes (11,11A) and return pipes (12,12A). Each valve is connected to the actuator (5) so that pressurised water is fed to or returned from only one side (5A,5B) of the piston. The first and second valves (16,17) are connected to an electrical power source (34) via a switch (30) and timer (29), the arrangement being such that when the switch (30) is actuated, pressurised water is supplied from the source (35) to one side (5A) of the piston (13) in the actuator (5) and simultaneously exhausted from the other side (5B) of the piston (13) to move it from a rest position in the cylinder in a first direction until the timer causes the valves (16,17) to change over and pressurised water is then supplied to the other side (5B) of the piston (13) and exhausted from the opposite side (5A) of the piston (13) to move it in the opposite direction in the cylinder of the actuator (5) and return it to its rest position. |
