Brake cable operating means of the overcenter toggle type

Claim 1

Brake cable operating means of the overcenter toggle type for axially displacing the inner cable member of a coaxial brake cable assembly relative to the concentrically arranged tubular outer sheath member, comprising (a) mounting plate means adapted for connection with a fixed support, said mounting plate means including a pair of spaced parallel mounting plates; (b) anchor means rigidly connecting one end of the outer sheath member between said plates at one end of said mounting plate means, thereby to prevent axial displacement of said outer sheath member relative to said mounting plate means, said inner cable member extending axially beyond said outer sheath member and through said anchor means into the space between said plates; (c) guide means connecting the free end of the inner cable member with said mounting plate means for linear axial displacement relative to said outer sheath member; (d) an operating lever pivotally connected at one end with the other end of said mounting plate means, the pivot axis of said operating lever being normal to said plates; and (e) a generally bow-shaped rigid non-extensible connecting link pivotally connected at opposite ends with an intermediate portion of said lever and with the free end of said inner cable member, respectively, the pivot axis of said link being parallel with the pivot axis of said operating lever, said operating lever being pivotable between brake released and brake applied positions in which the free end of the inner cable member is displaced toward and away from the said one end of the outer sheath member, respectively, the pivotal connection between said lever and said link and the central portion of said link being arranged, when said lever is in the brake fully applied position, on opposite sides of the plane containing the pivot axis of the lever and the axis of the pivotal connection between said link and the inner cable member; (f) the pivot axis of said lever being laterally offset from the plane which extends normal to said mounting plates and which contains the guide axis of linear displacement of the free end of said inner cable member, thereby to reduce wear on said guide means and to provide greater efficiency in the operation of said brake cable operating means; (g) said connecting link including a pair of pivotally connected sections that are foldable to permit movement of the operating lever beyond the overcenter brake fully applied position, thereby to afford reserve travel of the inner brake cable at a reduced mechanical advantage under emergency brake-operating conditions.