主权项 |
1. A chair configurable to provide a substantially horizontal seating surface when the chair is disposed on an angled surface, said chair comprising:
a back frame comprising a pair of telescoping back legs, each back leg including an upper back leg tube and a lower back leg tube that is slidingly disposed within the upper back leg tube; a seat frame pivotally connected to the back frame such that the seat frame can be transitioned between a collapsed position and an expanded position, the seat frame comprising a pair of opposing side tubes each having an end cap disposed at an end thereof; a pair of front legs having the seat frame pivotally connected thereto; and a pair of locking mechanisms, each locking mechanism comprising a locking key disposed within a hinge and lock housing that is fixedly connected to a respective one of the upper back leg tubes, each locking key including:
a base plate that includes a locking aperture through which the respective lower back leg tube extends:a canting spring disposed between the base plate and a bottom plate of the hinge and lock housing; anda tongue extending from the base plate, the tongue structured and operable to control selectively positioning the respective locking key into each of:
an engaged position that binds the lower back leg tube within the locking aperture such that the lower back leg tube cannot slide into the upper back leg tube, anda disengaged position that allows the lower back leg tube to freely slide within the locking aperture and the upper back leg tube, the tongue comprises:
an arm that, at a first end, is connected to and extends from the base plate at an obtuse angle; anda fulcrum plate that extents at an angle from an opposing second end of the arm such that: when the chair is in the collapsed position the end cap of the respective seat frame side tube contacts the fulcrum plate, thereby placing the locking key into the disengaged position, and when the chair is in the expanded position the end cap of the respective seat frame side tube is not in contact with fulcrum plate allowing the canting spring to place the locking key in the engaged position. |