Rotary pumping apparatus with radial seal assemblies on piston

An apparatus for pumping a fluid comprising:

• housing means having a body with a cylindrical inner wall surrounding a chamber, a plurality of pairs of intake and exhaust valve means mounted on the body for controlling the flow of fluid into and out of said chamber, said pairs of intake and exhaust valve means being located around the body in communication with the chamber, shaft means rotatably mounted on the housing means, a piston located in said chamber, a first eccentric member secured to the shaft means, means mounting the piston on the first eccentric member, a second eccentric member rotatably mounted on the housing means, means mounting the piston on the second eccentric member, a third eccentric member rotatably mounted on the housing means, means mounting the piston on the third eccentric member, said second and third eccentric members being spaced from each other and radially spaced from the first eccentric member whereby on rotation of the shaft means the first eccentric member rotates the piston about an axis offset from the axis of rotation of the shaft means, said second and third eccentric members limiting the amount of angular movement of the piston as the piston moves within the chamber, a plurality of seal assemblies mounted on the housing means and located in said chamber, said seal assemblies being arranged around said piston to divide the chamber into separate arcuate segments and locate a seal assembly between each pair of intake and exhaust valve means, said piston having circumferentially spaced slots for each seal assembly whereby the piston moves relative to each seal assembly during movement of the piston in the chamber, each seal assembly having a seal means located in sealing engagement with said cylindrical inner wall, each of said seal means and housing means having cooperating means for allowing limited arcuate movement of the seal assembly and restrict radial movement thereof during movement of the piston, said body having side walls located adjacent opposite sides of the piston, said cooperating means comprising arcuate transversely aligned slots in said side walls open to opposite sides of the piston and spaced radially inward of said cylindrical inner wall, each of said slots having a radius that is substantially the same as the radius of the cylindrical inner wall, each seal means having projections extended into said aligned slots in the side walls to restrict radial movement of the seal assembly and maintain the seal means in sealing engagement with said cylindrical inner wall during movement of the piston in said chamber.

An apparatus for pumping a fluid comprising:

• housing means having a cylindrical inner wall surrounding a chamber, valve means for controlling the flow of fluid into and out of said chamber, a piston located within said chamber, means including first eccentric means rotatably mounted on the housing means, said piston being rotatably mounted on the first eccentric means whereby angular movement of the first eccentric means moves the piston within said chamber, second eccentric means rotatably mounted on the housing means, said piston being movably associated with said second eccentric means to limit angular movement thereof during its movement in the chamber, a plurality of seal assemblies movably mounted on said housing means, said seal assemblies being located in sealing engagement with said cylindrical inner wall of the housing means and arranged around said piston to divide the chamber into separate arcuate chamber segments, each seal assembly having blade means extended between the piston and housing means, said piston having general radial movement relative to each seal assembly, each seal assembly and housing means having cooperating means for allowing limited arcuate movement of the seal assembly and restrict radial movement thereof during movement of the piston whereby said moving piston draws fluid into said chamber segments and pumps the fluid from said chamber segments, said cooperating means comprising arcuate slots in said housing means open to the piston and spaced radially inward of said cylindrical inner wall, each of said slots having a radius that is substantially the same as the radius of the cylindrical inner wall, each blade means having projection means extended into the arcuate slots to restrict radial movement of the blade means and maintain the seal assemblies in sealing engagement with said cylindrical inner wall of the housing means during movement of the piston in the chamber.