Patent ID: 6557456
Filing Date: 2003-05-06
Classification: B66F,F15B

Abstract:
An actuator for use with a lift truck having an extendible mast, said actuator comprising:an elongated housing; an axial bore formed in said housing, and having a first end and a second end; a ram slidably and sealingly mounted in said bore for axial movement between an extended ram position and a retracted ram position, said ram having one end disposed in said bore and an opposing end extending out of said bore second end; and a pressure ring slidably and sealingly mounted in said bore between said ram one end and said bore second end, wherein filling said bore with a fluid causes said ram to move from the retracted ram position toward the extended ram position, and engagement of said ram one end with said pressure ring traps fluid between said pressure ring and said bore second end to resist movement of said ram toward the extended ram position.