Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
345 words
In a piston and cylinder arrangement including a cylinder having a bore, a piston slidably engaged in said bore of the cylinder and a piston rod connected to and projecting from said piston substantially concentrically within said bore, said piston rod beinG of smaller diameter than said cylinder bore to define an annular chamber around the piston rod which is closed at one end by said piston, a bearing ring slidable on said piston rod remote from said piston, said bearing ring being of segmental longitudinal section to provide a spherical outer surface, a bearing bush receiving said bearing ring and having a spherical inner surface seating thereon to permit rocking of said bearing ring with respect to the bearing bush, said bearing bush having parallel opposite end faces and an outer surface substantially parallel to the axis of said cylinder, said cylinder having parallel side faces extending radially of said bore commencing radially outwardly of said piston rod and spaced apart closely to receive said bearing bush therebetween, and having an inner surface extending between said side faces and spaced radially outwardly of said outer surface of said bearing bush to present a clearance chamber surrounding said bearing bush so that said bearing bush may be displaced radially, seal means for sealing between that end face of said bearing bush facing said piston and its corresponding side face of the cylinder whereby, in conjunction with said bearing ring, to close the other end of said annular chamber, means for pressurizing said annular chamber to move said piston and piston rod and whereby axial thrust tends to be set up between the other end face of said bearing bush and its corresponding side face of the cylinder such that radial movement of said bearing bush is difficult, means for defining a balance space between said other end face of said bearing bush and its corresponding side face of the cylinder, and passage means for connecting said annular chamber to said balance space, said balance space being of effective area substantially to balance said axial thrust.
Claim 2
Dependent Claim
345 words
In a piston and cylinder arrangement including a cylinder having a bore, a piston slidably engaged in said bore of the cylinder and a piston rod connected to and projecting from said piston substantially concentrically within said bore, said piston rod beinG of smaller diameter than said cylinder bore to define an annular chamber around the piston rod which is closed at one end by said piston, a bearing ring slidable on said piston rod remote from said piston, said bearing ring being of segmental longitudinal section to provide a spherical outer surface, a bearing bush receiving said bearing ring and having a spherical inner surface seating thereon to permit rocking of said bearing ring with respect to the bearing bush, said bearing bush having parallel opposite end faces and an outer surface substantially parallel to the axis of said cylinder, said cylinder having parallel side faces extending radially of said bore commencing radially outwardly of said piston rod and spaced apart closely to receive said bearing bush therebetween, and having an inner surface extending between said side faces and spaced radially outwardly of said outer surface of said bearing bush to present a clearance chamber surrounding said bearing bush so that said bearing bush may be displaced radially, seal means for sealing between that end face of said bearing bush facing said piston and its corresponding side face of the cylinder whereby, in conjunction with said bearing ring, to close the other end of said annular chamber, means for pressurizing said annular chamber to move said piston and piston rod and whereby axial thrust tends to be set up between the other end face of said bearing bush and its corresponding side face of the cylinder such that radial movement of said bearing bush is difficult, means for defining a balance space between said other end face of said bearing bush and its corresponding side face of the cylinder, and passage means for connecting said annular chamber to said balance space, said balance space being of effective area substantially to balance said axial thrust.
Claim 3
Dependent Claim
18 words
In a piston and cylinder arrangement as defined in claim 1 including means for pressurizing said clearance chamber.
Claim 4
Dependent Claim
69 words
In a piston and cylinder arrangement as defined in claim 2 including an end cap on said cylinder beyond said clearance chamber, said end cap having a stepped inner side wall axially spaced from the end of said cylinder to define a radial clearance space around said piston rod, and an annular dirt scraper surrounding said piston rod and having an annular flange received in said radial clearance space.
Claim 5
Dependent Claim
69 words
In a piston and cylinder arrangement as defined in claim 1 including an end cap on said cylinder beyond said clearance chamber, said end cap having a stepped inner side wall axially spaced from the end of said cylinder to define a radial clearance space around said piston rod, and an annular dirt scraper surrounding said piston rod and having an annular flange received in said radial clearance space.