Patent ID: 7568878

Claim:
A loader boom arm comprising: a) a post rigidly attachable to a vehicle; b) a lower arm extending along a lower arm axis, the lower arm having a proximal end and a distal end, the proximal end being pivotally connected to the post at a first pivot point; c) a pivoting mechanism coupled to the post and the lower arm for pivoting the lower arm about the first pivot point in an angular direction of rotation wherein the pivoting mechanism comprises a hydraulic cylinder extending from the post and attached to the lower arm at a point near the distal end thereof; d) an upper arm extending along an upper arm axis, the upper arm axis being oriented at an angle to the lower arm axis, the upper arm having a proximal end pivotally connected to the distal end of the lower arm at a second pivot point, and a distal end shaped for receiving a work implement; and e) a link arm pivotally connected to the post and to the upper arm, the link arm being configured and located for rotating the upper arm about the second pivot point as the lower arm is pivoted by the pivoting mechanism, such that the upper arm rotates further in the angular direction of rotation than the lower arm, thereby changing the angle between the lower arm axis and the upper arm axis, the link arm having a first end pivotally coupled to the post at a third pivot point located below the lower arm axis and a second end pivotally coupled to the upper arm at a fourth pivot point located above the lower arm axis when the lower arm is in a lowered position.