Patent ID: 7654787

Claim:
A tool holder for tools for cranes, the tool holder comprising: two double-acting hydraulic cylinders arranged in parallel and functioning together, said cylinders being configured to detachably lock a tool to the tool holder; at least two first hydraulic coupling units on the tool; at least two second hydraulic coupling units configured to be connected with said first hydraulic coupling units; at least two hydraulic lines; valve means provided with switching means, said valve means being configured to selectively connect said hydraulic lines to said hydraulic cylinders or to said first hydraulic coupling units; each said coupling unit being connected to said valve means by a hydraulic coupling line; each said hydraulic cylinder being connected to said valve means by at least one hydraulic cylinder line; a connection line coupled between each said hydraulic coupling line and one of said hydraulic cylinder lines; and a non-return valve in each said connection line, said non-return valve being directed to only permit flow from a respective said hydraulic coupling line to said hydraulic cylinder line.