Patent ID: 8602371

Claim:
An adjustment bracket assembly comprising: an adjustment shaft, with said shaft having at least first and second external thread paths, with said first thread path being different in configuration from said second thread path; an adjustment bracket for engagement with said adjustment shaft, with said adjustment bracket comprising having at least first and second internal thread paths for engagement with said first and second thread paths of said adjustment shaft; wherein rotation of said shaft or bracket in relation to each other results in differential movement of at least two subunits of said shaft or said bracket; wherein said adjustment bracket comprises: a first bracket subunit, said first bracket subunit having said first internal thread path; and a second bracket subunit, said second bracket subunit having said second internal thread path; in which said adjustment shaft comprises a first shaft subunit and a second shaft subunit, with said first shaft subunit having an external thread path configured for engagement with one of said internal thread paths of said bracket, so that when said bracket is rotated in relation to said shaft, said first bracket subunit and said second bracket subunit move differentially in relation to one another.