Positive drive for sliding gate operation

A security gate assembly, comprising:

• a gate panel laterally movable between open and closed positions;
• a drive rail fixed to the gate panel and movable with the gate panel laterally between the open and closed positions, the drive rail having a first drive surface;
• a linear drive portion having a first plurality of teeth thereon with a first rolling tooth profile, the linear drive portion being coupled to the first drive surface and defining a toothed second drive surface opposite the first drive surface;
• a support structure adjacent to the drive rail, wherein the drive rail is moveable laterally relative to the support structure;
• one or more drive motors coupled to the support structure;
• a first drive wheel attached to the one or more drive motors and being rotatable upon activation of the one or more drive motors, the first drive wheel engaging the first drive surface and imparting a first drive force on the drive rail upon rotation of the first drive wheel to move the drive rail axially;
• and
• a second drive wheel attached to the one or more drive motors and engaging the second drive surface, the second drive wheel having a plurality of second teeth disposed about a circumference and that have a second rolling tooth profile substantially corresponding to the first rolling tooth profile, wherein the second plurality of teeth mate with the first plurality of teeth, wherein rotation of the second drive wheel imparts axial and normal forces via a rolling teeth interface between the first and second teeth for driving the drive rail axially and moving the gate panel.

A method of forming a security gate assembly, comprising:

• attaching a drive rail to a gate panel, the drive rail having a longitudinal axis and a first drive surface;
• attaching a linear drive portion to the drive rail, the linear drive portion having a first plurality of teeth thereon with a first rolling tooth profile, the linear drive portion being coupled to the first drive surface and defining a toothed second drive surface opposite the first drive surface;
• and
• attaching first and second drive assemblies to a support structure adjacent to the drive rail, wherein the drive rail and gate panel are moveable as a unit laterally relative to the support structure, the first drive assembly having a first drive motor and first drive wheel pivotally coupled to the support structure, and the second drive assembly having a second drive motor and second drive wheel pivotally coupled to the support structure, the first drive wheel engaging the first drive surface and imparting a first drive force on the drive rail upon rotation of the first drive wheel to move the drive rail axially, and the second drive wheel engaging the second drive surface, the second drive wheel having a plurality of second teeth disposed about a circumference and that have a second rolling tooth profile substantially corresponding to the first rolling tooth profile, wherein the second plurality of teeth mate with the first plurality of teeth, wherein rotation of the second drive wheel imparts axial and normal forces via a rolling teeth interface between the first and second teeth for driving the drive rail axially and moving the gate panel.

A linear gate drive assembly for use with a gate panel, comprising:

• an elongated drive rail connectable to the gate panel, the drive rail having a longitudinal axis and opposing first and second surfaces, the first surface defining a first drive surface;
• a gate operating device adjacent to the drive rail, the gate operating device having a support structure;
• a first drive arm pivotally connected to the support structure and being pivotal relative to the support structure in a pivot plane substantially perpendicular to the first surface of the drive rail;
• a second drive arm pivotally connected to the support structure and being pivotal relative to the support structure in the pivot plane;
• a first drive motor attached to the first drive arm and being pivotal with the first drive arm as a unit relative to the support structure;
• a second drive motor attached to the second drive arm and being pivotal with the second drive arm as a unit relative to the support structure;
• a linear drive member having a first plurality of teeth thereon, the linear drive member being attached to the drive rail and defining a toothed drive surface opposite the first drive surface with the first plurality of teeth projecting away from first drive surface, the first plurality of teeth being oriented substantially perpendicular to the longitudinal axis of the drive rail, the first plurality of teeth defining substantially arcuate first drive portions of the toothed drive surface, and each of the first plurality of teeth having a substantially arcuate first crest portion and a substantially arcuate first root portion;
• a first drive wheel attached to the first drive motor and engaging the first drive surface, wherein the first drive wheel rotates upon activation of the first drive motor and rotation of the first drive wheel and the engagement with the first drive surface imparts a first drive force on the drive rail to move the drive rail in a direction substantially parallel to the longitudinal axis of the drive rail, the first drive wheel, the first drive motor and the first drive arm being pivotable as a first unit relative to the support structure;
• and
• a second drive wheel attached to the second drive motor and engaging the toothed drive surface of the linear drive member, the second drive wheel having a second plurality of second teeth thereon disposed about a circumference, wherein the second plurality of teeth mate with the first plurality of teeth being are oriented substantially perpendicular to the longitudinal axis of the drive rail, the second plurality of teeth defining substantially arcuate second drive portions that mate with the first drive portions, each of the second plurality of teeth having a substantially arcuate second crest portion and a substantially arcuate second root portion, wherein upon rotation of the second drive wheel the first crest portion of the tooth on the toothed drive surface rolls along the second root portion of an adjacent tooth on the second drive wheel, and the second crest portion of a tooth on the second drive wheel rolls along the first root portion of a tooth on the toothed drive surface to impart axial and normal forces for driving the drive rail longitudinally to move the gate panel between open and closed position;
• and
• a clamp assembly connected to the first and second drive arms and applying normal forces between the first drive wheel and the drive surface and between the second drive wheel and the linear drive member.