Coupling hook for tractor hitch - has cable operated swinging plate controlling release finger, swung between open and closed positions

摘要

The connecting hook for the three point hitch of a tractor includes a locking arm (4) with an enlarged nose which is advanced and retracted so as to lock or release the shackle (3) on the device to be attached to the tractor. This arm is connected by a hinge to an extension of a cover plate (7) which fits over an opening at the rear of the body of the hook. This plate has an anchorage (8) for a control cable so that it can be swung between positions for operating the locking arm. When the plate is tilted back into the release position, it is swung back to fit over a bulging rim (10) at the rear of the body, uncovering the top opening. At the same time, a pin (13) mounted between its side flanges travels down sloping slots (11) in the sides of the body, locking the arm in its position of maximum tilt to free the shackle. This prevents the arm from being swung down by a spring (5) secured near its hinge axis.