Auxiliary steerable wheels for vehicles

Claim 1

A truck having a frame including spaced longitudinal members and a rear connecting cross member, forward steerable and rear drive wheels directly supporting said frame members, an auxiliary axle assembly connected to said frame members for relative vertical movement and including an axle which extends transversely of and below the truck frame and fluid pressure suspension means carried by said axle; each end of said axle having a kingpin and a support wheel mounted on said kingpin for dirigible movement, the projected axis of each kingpin being forwardly disposed of the ground engagement area of the respective wheel, said wheels being dirigible and having means connecting the two wheels so that they steer together, the variable fluid pressure suspension means being alongside the frame whereby the axle may be raised fully to an elevation immediately beneath said frame, said suspension means comprising at least one rigid bracket secured and projecting from the truck frame near or above the upper dimensions thereof and over the auxiliary axle assembly, vertically expansible fluid pressure cylinder and piston means interposed between each bracket and said axle assembly and alongside the truck frame, manually controllable fluid pressure supply means connected to said cylinder means to pressurize the same for the selected support of the truck frame at the location of said brackets, and manually controlled means for relieving the pressure of said supply means and for raising said axle to said elevated position.