Abstract: A combine header transport trailer for transporting a combine header. The trailer includes mechanical jacks for raising and lowering the header bar thereon and for moving the header bar inwardly and outwardly with respect to the trailer.

Abstract: A combine header transport trailer for transporting a combine header. The trailer includes electrically operated jacks or screw actuators for raising and lowering the header bar thereon and for moving the header bar inwardly and outwardly with respect to the trailer.

Abstract: The invention provides a closed center rotary valve and a power-assisted steering mechanism for a motor vehicle incorporating the rotary valve.The closed center rotary valve comprises cooperating relatively rotatable sleeve and core members having cooperating axially-extending grooves therein and means relatively biassing the members towards a neutral position.Said grooves comprise at least one inlet groove connectable to a source of fluid under pressure, a cylinder groove angularly spaced from the inlet groove on each side thereof and connectable to opposite sides of a double-acting piston-and-cylinder, and a return groove in overlapping relation with each of the cylinder grooves in the neutral position of the valve and connectable to a reservoir for the fluid under pressure, the inlet groove being closed from communication with the cylinder and return grooves in the neutral position of the valve.

Abstract: A logging truck having a load supporting frame provided with a plurality of log-supporting bunks has a false bunk arrangement disposed over the load supporting center of a wheel assembly supporting the load supporting frame for applying a positive force to logs disposed on the bunks and relieving flexing of the load supporting frame.