IMPROVEMENTS IN ROTARY PUMPS
Year: 1880

page_text: PROVISIONAL SPECIFICATION left by Charles Shaw at the Office of the
Commissioners of Patents on the 18th March 1880.
CHARLES SHAW, of Wolverhampton, in the County of Stafford, Architect and
Surveyor. "IMPROVEMENTS IN ROTARY PUMPS."
This Invention relates to that class of rotary pumps in which an eccentric disc
revolves in a cylinder, the suction and delivery spaces in the cylinder being separated
by the disc, and by a valve bearing upon the periphery of the disc which is raised
and lowered as the disc revolves.
According to this Invention, a valve of peculiar construction is hinged within a
case which is exterior to the cylinder in which the disc revolves. The motion of
the hinged valve is in the same plane as the motion of the disc. A part of the said
valve is quadrant-shaped, and enters the cylinder through an opening in the periphery
thereof, and bears upon the disc. The outer curve of the quadrant is struck from the
hinge as a centre. The pump is put to work with the axis of the cylinder horizontal,
and with the valve above. A passage is formed through the top of the case
in which the valve is hinged for the suction inlet, and an opening (preferably tapering
smaller downwards) is formed through the back of the valve (that is, through a
part which extends from the hinge to the springing of the quadrant), through
which the suction fluid is drawn. By the suction fluid being drawn through the
back of the valve, and especially through a taper hole therein, as described, the valve
is kept down with the lower edge of the quadrant bearing properly upon the
periphery of the disc. The outer periphery of the quadrant works against a face
extending upwards from the inside of the cylinder, so as to prevent the delivery.
fluid from leaking into the suction; and the sides of the quadrant fit the cylinder
and case sideways for the same purpose. The opening into the cylinder, through
which the quadrant passes, is extended on the inner side of the quadrant to allow
the suction liquid to pass through from the case into the cylinder. The delivery
passage passes out immediately beyond the face aforesaid, and there is therefore
practically no point at which the pump does not throw, the space between the
delivery and suction passages being simply the thickness of the face against which
the periphery of the quadrant works, and the thickness of the lower edge of the
said quadrant. In addition to the valve before-mentioned, it is preferred to have
retention valves, one in the suction and one in the delivery pipes.

page_text: The pump may if desired work the reverse way to that described, in which case
of course the suction becomes the delivery and the delivery becomes the suction. In
this case also the valve is not drawn down by the suction, the pressure being against
the inside of the valve. The back of the valve is therefore made preferably open
or skeleton to allow the delivery liquid to pass freely therethrough, and prevent the
pressure from raising the lower edge of the quadrant from off its bearing upon
the disc. The valve may be weighted to ensure its bearing properly upon the
disc.
In either case, the valve being continually kept down as aforesaid to bear upon
the disc, it of course rises and falls with the disc.