The present invention relates to a double acting hydraulic piston and cylinder assembly and a method for assembling the same.
Double acting, double ended cylinders include a piston rod which extends from both ends of the cylinder. The piston operates in both directions by introducing fluid under pressure alternatively to opposite sides of the piston.
In the past, pistons for such double ended cylinders have been fastened to the rod by several different methods. One method comprises threading a two piece rod together within the piston so that the rod extends from opposite ends of the piston. Another method involves welding the piston in place on the rod. A third method involves installing collars on both sides of the piston for holding the piston against axial movement on the rod. A fourth method involves pinning the piston to the rod. Therefore, a primary object of the present invention is the provision of an improved double acting hydraulic piston and cylinder assembly and an improved method for assembling same.
A further object of the present invention is the provision of means for securing the piston to the rod which eliminates the disadvantage of distortion of the rod which occurs in the present method of welding the piston to the rod.
A further object of the present invention is the provision of a device for attaching the piston to the rod so that the piston can be fitted loosely over the rod and then attached securely in place.
A further object of the present invention is the provision of a means for holding the piston positively in place once it is installed so that it will not move in either direction axially on the rod.
A further object of the present invention is the provision of a device which may be disassembled easily for removing the piston and for repacking or rebuilding the cylinder and piston assembly.
A further object of the present invention is the provision of an improved hydraulic piston and cylinder assembly wherein the piston rod is straight and completely concentric since there is only one part to the piston rod rather than the prior method of threading two piston rod segments into the piston.
A further object of the present invention is the provision of a hydraulic piston and cylinder assembly which has interchangeable parts adapted to high production techniques.