20120093572 | ATTACHMENT COUPLER FOR HEAVY MACHINERY - An attachment coupler for heavy machinery, which detachably installs an attachment to an arm of the heavy machinery, includes a coupler body coupled to the arm of the heavy machinery, a fixed hook formed on the coupler body and coupled to the attachment via a first coupling pin, a movable hook rotatably coupled to the coupler body via a hinge axis and coupled to the attachment via a second coupling pin, a hydraulic cylinder that rotates the movable hook to be coupled to or disengaged from the second coupling pin, and a locking device that includes a locking hook and an engagement device. The locking hook is rotatably coupled to the coupler body via a hinge axis and closes an open end of the fixed hook while being coupled to the first coupling pin. The engagement device rotates in association with the rotation of the movable hook. | 04-19-2012 |