IMPROVEMENTS IN ROTATORY PUMPS
Year: 1864

page_text: LETTERS PATENT to Alexander Rodger, of the Firm of Rodger, Best,
& Co., of Liverpool; for the Invention of "IMPROVEMENTS IN ROTATORY
PUMPS." -A communication from abroad by Richard Newton, residing
at Buenos Ayres.
Sealed the 30th September 1864, and dated the 8th April 1864.
PROVISIONAL SPECIFICATION left by the said Alexander Rodger at the
Office of the Commissioners of Patents, with his Petition, on the 8th
April 1864.
I, ALEXANDER RODGER, of the Firm of Rodger, Best, & Co., of Liverpool,
do hereby declare the nature of the Invention for "IMPROVEMENTS IN ROTATORY
PUMPS," to be as follows:-
ཧྥ་
In constructing rotatory pumps, according to this Invention, the inner surface
of the sides of the shell or case of the pump is made of the following shape:-
Two opposite sides of the case are composed of two quadrants, one of which is
of a greater radius than the other, and the two quadrants are struck from a
common centre; the portions of the sides which connect the ends of one
quadrant and the ends of the other quadrant are composed of parabolic curves
which are formed so as to allow a straight line that is of a length equal to the
length of the radii of the two quadrants added together to revolve freely inside
of the shell, the line then sliding through the conimon centre of the quad-
rants; through one of these parabolic portions of the sides an inlet passage is
formed, and through the opposite portion an outlet passage is formed; grooves

page_text: are also formed in the portions of the sides of the case nearest to these
passages to allow water or other fluid to pass freely to or from them. The two
ends of the shell or case are made flat, as is usual, and the two flat ends carry
bearings in which the axis of the revolving portion of the pump turns. The
revolving portion of the pump is composed of a drum, the radius of which is
equal to the radius of the smaller quadrant, and the axis of the drum is
concentric with the centre of the two quadrants. Through the centre of the
drum two slots are formed at right angles to each other, each slot passes from
one side of the circumference of the drum to the other, the slots thus cross
each other in the centre of the drum, and by this means form four radial
slots; in each of these slots a flat board is capable of sliding in such manner
that the board may either project from the circumference of the drum or may
lie within its radial slot or recess. When the outer end of any of the slots is,
by the revolution of the drum, brought towards the smaller quadrant, the
board in that slot will be caused to lie within its slot, the board that works in
the opposite slot will then be projecting from its slot and its end caused to
work against or be in contact with the surface of the larger quadrant, in con-
sequence of the inner ends of each of the boards having projections formed
upon it, which, when one of the boards is pushed into its slot, pushes the
opposite board out of its slot. The outer case of the pump is, when in use,
placed by preference so that the inlet pipe is at the bottom of the case, and
the outlet pipe at its top. When the case is placed in this position, and the
axis of the drum is caused to revolve, the boards will as they come round
towards the inlet passage drop down on to the sides of the case by their
gravity, and will drop away from the sides of the case when passing the outlet
passage; the boards will, however, have no sliding motion in their slots whilst
they are moving round past the larger quadrants, at which time they are
acting as the suckers of the pump. Pumps constructed in this manner are
well adapted for pumping or forcing water, air, or other fluid.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed so
by the said Alexander Rodger in the Great Seal Patent Office on the
4th October 1864.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ALEXANDER
RODGER, of the Firm of Rodger, Best, & Co., of Liverpool, send greeting..
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters 35
Patent, bearing date the Eighth day of April, in the year of our Lord

page_text: One thousand eight hundred and sixty-four, in the twenty-seventh year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said Alexander Rodger, Her special licence that I, the said
Alexander Rodger, my executors, administrators, and assigns, or such
others as I, the said Alexander Rodger, my executors, administrators, and
assigns, should at any time agree with, and no others, from time to time
and at all times thereafter during the term therein expressed, should and
lawfully might make, use, exercise, and vend, within the United Kingdom of
Great Britain and Ireland, the Channel Islands, and Isle of Man, an' Inven-
tion for "IMPROVEMENTS IN ROTATORY PUMPS," a communication to me from
abroad by Richard Newton, a person resident at Buenos Ayres, upon the
condition (amongst others) that I, the said Alexander Rodger, my executors
or administrators, by an instrument in writing under my, or their, or one
of their hands and seals, should particularly describe and ascertain the nature
of the said Invention, and in what manner the same was to be performed,
and cause the same to be filed in the Great Seal Patent Office within
six calendar months next and immediately after the date of the said Letters
Patent.
NOW KNOW YE, that I, the said Alexander Rodger, do hereby declare
the nature of the said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement thereof, that is to say :-
In constructing rotary pumps, according to this Invention, the inner surface
of the sides of the shell or case of the pump is made of the following shape:-
Two opposite sides of the case are composed of two quadrants, one of which is
of a greater radius than the other, and the two quadrants are struck from a
common centre; the portions of the sides which connect the ends of one
quadrant and the ends of the other quadrant are composed of parabolic curves,
which are formed so as to allow a straight line that is of a length equal to the
O length of the radii of the two quadrants added together to revolve freely inside
of the shell, the line then sliding through the common centre of the quadrants ;
through one of these parabolic portions of the sides an inlet passage is formed,
and through the opposite portion an outlet passage is formed; grooves are
also formed in the portions of the sides of the case nearest to these passages
to allow water or other fluid to pass freely to or from them. The two ends
of the shell or case are made flat, as is usual, and the two flat ends carry
bearings in which the axis of the revolving portion of the pump turns. The
revolving portion of the pump is composed of a drum, the radius of which is
equal to the radius of the smaller quadrant, and the axis of the drum is

page_text: concentric with the centre of the two quadrants. Through the centre of the
drum. two, slots are formed at right angles to each other; each slot passes
from one side of the circumference of the drum to the other; the slots thus
cross each other in the centre of the drum, and by this means form four radial
slots; in each of these slots a flat board is capable of sliding such manner
that the board may either project from the circumference of the drum or may
lie within its radial slot or recess. When the outer end of any of the slots is,
by the revolution of the drum, brought towards the smaller quadrant, the
board in that slot will be caused to lie within its slot; the board that works
in the opposite slot will then be projecting from its slot, and its end caused to
work against or be in contact with the surface of the larger quadrant, in
consequence of the inner ends of each of the boards having projections formed
upon it, which, when one of the boards is pushed into. its slot, pushes the
opposite board out of its slot. The outer case of the pump is, when in use,
placed by preference so that the inlet pipe is at the bottom of the case, and
the outlet pipe at its top. When the case is placed in this position and
the axis of the drum is caused to revolve, the boards will, as they come round
towards the inlet passage drop down on to the sides of the case by their
gravity, and will drop away from the sides of the case when passing the outlet
passage; the boards will, however, have no sliding motion in their slots whilst
they are moving round past the larger quadrants, at which time they are
acting as the suckers of the pump. Pumps constructed in this manner are
well adapted for pumping or forcing water, air, or other fluid.
And in order that my Invention may be fully understood and readily carried
into effect, I will proceed to describe the Drawings hereunto annexed.
DESCRIPTION OF THE DRAWINGS.
Figure 1 is a side view, and Figure 2 a transverse section of a pump
constructed according to this Invention.
•
a, a, is the shell or case of the pump, having two flat ends b, b, carrying the
bearings of the rotary portion of the pump, as is usual. The form of the
interior of the shell or case is seen in Figure 2; c, c, are the two opposite
quadrants struck from a common centre, one quadrant being struck from a
greater radius than the other. The portions d, d, of the interior of the case
are composed of curves which, as above stated, are formed so as to allow a
straight line that is of a length equal to the length of the radii of the two
quadrants added together to revolve inside the shell, the line then sliding
through the common centre of the quadrants. The outlet pipe e opens into
the case through one of the curved parts d, and the inlet pipe through the

page_text: other curved part d. f is the interior revolving drum, the axis of which is
concentric with the common centre of the quadrants, and is carried by
bearings in the flat ends 6 of the case or shell; and to the axis of the drum
a rotary motion is given in any suitable manner. In the drum are formed
four radial slots, in each of which a flat board or slide works; these boards
are shewn separately at Figure 3, and, as is there shewn, the boards have
projections upon them of such a length that when one board is caused to lie
within its slot in the drum the board in the opposite slot will project outwards
from the drum. Small springs are placed at the ends of the projections on
the boards, as is shewn at Figure 8, so that the boards are constantly pressed
outwards against the sides of the shell or case; grooves are, by preference,
made in the sides of the case at the points g and h, but this is not essential.
When the axis of the drum f is caused to rotate, the boards or slides carried
by it will in succession be brought round opposite to the larger quadrant, and
its outer end caused to sweep along it, the boards will then be acting as the
suckers of the pump, and will also be supporting the weight of the column of
water above the pump, and at this time the boards will have no sliding
motion, but will simply be carried round with the drum. Pumps constructed
as above described may be worked in any position; but, as before stated, it is
preferred to work them in the position shewn in the Drawing, the inlet pipe
then being at the bottom and the outlet pipe at the top of the case..
In witness whereof, I, the said Alexander Rodger, have hereunto set my
hand and seal, this Third day of October, in the year of our Lord One
thousand eight hundred and sixty-four.