Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
254 words
A fluid pressure unit comprising a first assembly, a second assembly, bearing means mounting said first assembly to said second assembly and adapted to permit relative rotation therebetween, said first assembly including means providing an internal cam surface and said second assembly including a plurality of cylinders of rectangular cross-section, an equal plurality of piston shoes of rectangular cross-section each contained within a different one of said cylinders, a cylindrical roller for each piston shoe rotatably mounted in a partcylindrical seating in the outer end thereof and adapted to follow a said cam surface, means for admitting pressurized lubricant to each of said seatings, means for admitting fluid to said cylinders, and means for discharging said fluid from said cylinders, each of said part cylindrical seatings for said rollers comprising a marginal portion adapted to contact said roller, a recessed portion adapted to be spaced from said roller, and means for admitting pressurized lubricant to said recessed portion whereby reaction forced between said roller and said cam surface are balanced by pressure of said lubricant on said roller, while said means for admitting pressurized lubricant to said recessed portion of said seating comprises an opening from said recessed portion through said piston shoe into said cylinder, whereby hydraulic working fluid in said cylinder serves additionally as said pressurized lubricant, and each of said piston shoes includes seal means for contacting the walls of said cylinders and means for admitting said working fluid behind said seals whereby said seals are urged against said cylinder walls.
Claim 2
Dependent Claim
254 words
A fluid pressure unit comprising a first assembly, a second assembly, bearing means mounting said first assembly to said second assembly and adapted to permit relative rotation therebetween, said first assembly including means providing an internal cam surface and said second assembly including a plurality of cylinders of rectangular cross-section, an equal plurality of piston shoes of rectangular cross-section each contained within a different one of said cylinders, a cylindrical roller for each piston shoe rotatably mounted in a partcylindrical seating in the outer end thereof and adapted to follow a said cam surface, means for admitting pressurized lubricant to each of said seatings, means for admitting fluid to said cylinders, and means for discharging said fluid from said cylinders, each of said part cylindrical seatings for said rollers comprising a marginal portion adapted to contact said roller, a recessed portion adapted to be spaced from said roller, and means for admitting pressurized lubricant to said recessed portion whereby reaction forced between said roller and said cam surface are balanced by pressure of said lubricant on said roller, while said means for admitting pressurized lubricant to said recessed portion of said seating comprises an opening from said recessed portion through said piston shoe into said cylinder, whereby hydraulic working fluid in said cylinder serves additionally as said pressurized lubricant, and each of said piston shoes includes seal means for contacting the walls of said cylinders and means for admitting said working fluid behind said seals whereby said seals are urged against said cylinder walls.
Claim 3
Dependent Claim
139 words
A unit according to claim 1, wherein said means for admitting fluid into said cylinders comprises a plurality of inlet ports, one communicating with each cylinder, a port plate disposed to one side of said cylinders and adapted to rotate relatively to said cylinders, and ports in said port plate registering with the inlet ports to the cylinders in turn upon relative rotation between said first and second assemblies, and said means for discharging said fluid from said cylinders comprises a plurality of outlet ports, one communicating with each cylinder, an outlet port plate disposed on the other side of said cylinders and adapted to rotate relatively to the cylinders, and outlet ports in said outlet port plate which register with said outlet ports from said cylinders in turn upon relative rotation between said first and said second assemblies.
Claim 4
Dependent Claim
146 words
A motor according to claim 1 wherein said first assembly comprises a ring surrounding said pistons and having an inward facing surface which constitutes said cam surface and said second assembly comprises a cylinder block which includes said cylinders, a circular extension of said cylinder block coaxial with the axis of relative rotation between said first and said second assemblies, a plurality of ports through which each of said cylinders communicates with a plurality of axial channels in said extension and a plurality of radial ports through which each of said axial channels communicates with radial ports formed in a pintle rigid with said ring and disposed around said extension, annular spaces surrounding said pintle, and external ports communicating with said annular spaces and adapted to register with said plurality of ports in said block in turn during relative rotation between said first and second assemblies.
Claim 5
Dependent Claim
52 words
A unit according to claim 1 wherein said means providing said cam surface comprises two generally semi-cylindrical parts, means mounting said parts so as to be movable towards and away from one another and means for moving said parts together or away from one another to vary the stroke of said pistons.
Claim 6
Dependent Claim
191 words
A unit according to claim 1 wherein at least one group of four pistons are equiangularly disposed around said axis of relative rotation and the form of said cam surface is such that each piston performs a plurality of cycles of reciprocation relative to the respective cylinder during each revolution of said first assembly relative to said second assembly and in all relative positions of the assemblies is one quarter of a cycle out of phase with two others of said pistons, and each cycle comprises, as said first assembly turns at constant speed relatively to said second assembly, a first portion during which said piston is at rest, a second portion during which said second piston accelerates in said respective cylinder a third portion during which said piston moves with constant velocity, a fourth portion during which said piston decelerates at a rate complementary to said acceleration during said second portion and a fifth portion during which the piston is at rest before the end of said half-cycle whereby the total displacement of said unit is independent of the angular position of said first assembly relatively to said second assembly.
Claim 7
Dependent Claim
36 words
A unit according to claim 5 wherein the form of said cam surface is such that said acceleration during said second portion and said deceleration during said fourth portion are uniform and are equal and opposite.
Claim 8
Dependent Claim
40 words
A unit according to claim 5 including two groups of four pistons, each piston being disposed diametrically opposite to and moving in phase witH a piston belonging to a different group whereby radial forces reacting on the rotor are balanced.