| 摘要 |
A jack for opening locked or barricaded doors (1) has a first hydraulic single acting piston and cylinder actuator (13) mounted on a casing (4) by which holding claws (5, 6) are forced into engagement with a door frame (2) to hold the jack in place. An arm (7) is pivotted on the casing (4) and an end opposite the pivot forced against the door (1) by a second hydraulic single acting piston and cylinder actuator (8) to open the door (1), reaction to the opening force being transmitted to the door frame (2) through the casing (4) and claws (5, 6). The reservoir (20) for the hydraulic fluid is provided to the rear of the piston (8b) of the actuator (8). The jack is readily portable and self-contained, and does not present a significant obstacle to entry through a door which has been forced using the jack. |
