PISTON ASSEMBLY FOR HYDRAULICALLY OPERATED PISTON-TYPE RETARDERS

摘要

The invention relates to a piston assembly for use in a hydraulically operated piston-type retarder. The piston assembly comprises a piston rod 1, a piston head 2, a speed spring 3, a closure member 4, a spacer member 5, a retainer member 9 and alock nut 6. The piston head 2 is provided with a set of first hydraulic fluid passageways with corresponding energy extraction ports 8 and a set of second hydraulic fluid passageways with corresponding idling ports 7. A method of retarding wagon stock is also provided.