Apparatus for removing fluid in a piston cylinder assembly

Claim 1

In a fluid piston cylinder assembly comprising a piston reciprocable relative to a piston cylinder and a piston rod attached to the piston, wherein during its operation fluid is introduced on the piston rod side of the piston wherein fluid adheres to the piston rod upon the relative displacement of the piston rod and piston cylinder, the improvement comprising a fluid removing means having at least two piston rod encircling scraper elements and a fluid receiving means including a piston rod encircling recess, said fluid removing means and said fluid receiving means located on said piston rod said of the piston, said scraper elements each having a varying inner diameter, means for locating one of said scraper elements to remove said adhering fluid from said piston rod during relative movement of said piston rod and said piston cylinder in a first direction, means for locating the other one of said scraper elements to remove said adhering fluid from said piston rod during relative movement of said piston rod and said piston cylinder in a second direction opposite to said first direction and, the inner diameter of said one scraper element decreases to a minimum inner diameter in said second direction so as to remove said adhering fluid on said piston rod upon said in said first direction relative movement, the inner diameter of said other scraper element decreases to a minimum inner diameter in said first direction so as to remove said adhering fluid on said piston rod upon said relative movement in said second direction, means for locating said recess of said receiving means between said minimum inner diameters of said two scraper elements, said recess constructed in a manner to immediately receive said fluid after removal from said piston rod and having different portions contiguous to said minimum inner diameters and having an outer diameter larger than the outer diameter of said scraper elements, said recess having an axial dimension which substantially equals the separation between said minimum inner diameters, gland plate means comprising two separate members, one of which has an annular projection, an opening in said piston cylinder for receiving said projection, said one member including a recess for receiving one of said scraper elements, the other member having an annular projection for contacting with an annular surface formed on said one member, said other member also having a recess for receiving said other scraper element, and being formed with said recess of said fluid receiving means, and means for securing said two members to said piston cylinder.