Patent ID: 7354237

Claim:
A loader boom arm comprising: a) a post rigidly attachable to a vehicle; b) a lower arm 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; d) an upper arm pivotally connected to the lower arm at a second pivot point, the upper arm having a free end shaped for receiving a work implement; e) a link arm pivotally connected to the post and to the upper arm, the link arm being configured and located for pivoting the upper arm about the second pivot point in the angular direction of rotation as the lower arm is pivoted about the first pivot point by the pivoting mechanism, the link arm having a first end portion pivotally connected to the post at a third pivot point positioned vertically below the first point, and a second end portion pivotally connected to the upper arm at a fourth pivot point positioned vertically above the second pivot point when the lower arm is in a lowered position; f) wherein a portion of the lower arm extending between the first pivot point and the second pivot point defines a lower arm link, a portion of the post extending between the first pivot point and the third pivot point defines a post link, a portion of the link arm extending between the third pivot point and the fourth pivot point defines a link arm link, and a portion of upper arm extending between the second pivot point and the fourth pivot point defines a upper arm link, wherein the post link, the lower arm link, the link arm link, and the upper arm link together form a four bar linkage, wherein the lower arm link has a longer length than the link arm link.