Patent ID: 8132280

Claim:
A dock leveler for forming a bridge between a loading dock and a trailer bed, said dock leveler comprising: a deck with a front end, rear hinged end and lock block secured to its lower surface, said lock block having a bottom surface spaced from said lower surface, and said deck being movable through a range of raised and lowered positions; a lip with a free end, a rear end hinged to said front end of said deck, a lower lip surface and a drive bracket extending from said lower lip surface to form a pivot point spaced from its said lower lip surface, said lip being operably movable between pendant and extended positions, said lip being biased by its own weight toward said pendant position; a lip extension assembly movable between engaged and disengaged positions and including an actuation bar and a drive rod, said actuation bar having a hinged rear end, a front end and a drive abutment located proximal said front end, said drive rod having a front end joined to said pivot point of said drive bracket and a rear end with a projection, said projection being positioned below said lock block to operably engage said bottom surface of said lock block when said lip is in its said pendant position, said actuation bar capturing said projection against said lock block when in said engaged position, said projection drivingly engaging said abutment when in said engaged position and releasing from said abutment when in said disengaged position, and said lip extension assembly is biased into said disengaged position when said deck is in a stored position, biased into said engaged position when said deck is raised to a raised position and biased to release from said engaged position when said deck is lowered to a transition position; a lip locking assembly movable between locked and unlocked positions, said lip locking assembly being biased into said locked position with said drive rod securely engaging said lock block to hold said lip in its said extended position when said deck is lowered to said transition position, and said locking assembly being biased into said unlocked position with said drive rod releasing from said lock block when said extended lip engages the trailer bed; and, wherein said actuation bar draws back to engage said lip extension assembly when said deck rises to said raised position, said lip extension assembly drives said lip into said extended position as said deck lowers from said raised position to said transition position, said locking assembly holds said lip in said extended position as said deck further lowers toward the trailer bed, and said locking assembly unlocks when said extended lip engages the trailer bed.