Arms for pantograph jack

Claim 1

A pantograph jack for lifting and lowering a vehicle chassis or the like comprising: a base support member on which movable parts of the jack are supported; a load mounting stand positioned in parallel relation to said base support member for holding the load thereupon during the lifting and lowering operations of the jack; a pair of upper arms, U-shaped in cross-section, each having one end thereof being rotatably mounted on said load mounting stand and having gear teeth provided upon opposite side walls of said U-shaped arms so as to face each other and on said one end thereof in meshing engagement with each other; the other end of each of said upper arms being operated by a manually operated rod member; a pair of lower arms, U-shaped in cross-section, each having one end thereof being rotatably mounted on said base support member and having gear teeth provided upon opposite side walls of said U-shaped arms so as to face each other and on said one end thereof in meshing engagement with each other; the other end of each of said lower arms being operated by said manually operated rod member; said gear teeth of said lower and upper arms comprising integral flange portions extending only inwardly at substantially a right angle from, and formed about the periphery of, said opposite side walls of said one end of each of said arms; and the width of each flange portion, upon which said gear teeth are disposed, being greater than that of each opposite side wall of each of said arms.