IMPROVEMENTS IN OSCIL- LATING PUMPS
Year: 1877

page_text: LETTERS PATENT to Adolph Rommel, of Moorgate Street Buildings, in the City
of London, Sworn Broker, for the Invention of "IMPROVEMENTS IN OSCIL-
LATING PUMPS." A communication from abroad by Karl Philipp Heinrich
Volkmar, of Williamsport, Lycoming County, Pennsylvania, United States.
Sealed the 7th June 1878, and dated the 11th December 1877.
PROVISIONAL SPECIFICATION left by the said Adolph Rommel at the Office
of the Commissioners of Patents on the 11th December 1877.
ADOLPH ROMMEL, of Moorgate Street Buildings, in the City of London, Sworn
Broker. "IMPROVEMENTS IN OSCILLATING PUMPS." A communication from abroad
by Karl Philipp Heinrich Volkmar, of Williamsport, Lycoming County, Pennsyl-
vania, United States.
This Invention relates to a peculiar construction, arrangement, and combination
of parts constituting an oscillating pump of extraordinary forcing power and of
extreme simplicity and cheapness of construction, and applicable for pumping out
mines and other like places.
The said improved pump consists essentially of a scroll plunger combined with a
central disc, which constitutes an oscillating plunger, the said parts being operated
by an eccentric and driving shaft working concentrically within the shell or casing
of the pump. The disc divides the cylinder of the pump into two parts by forming
a transverse mid division, two sets of inlet and outlet ports being situate one in each
of the two chambers of the pump. The shell of the pump is cast in two cylindrical
pieces joined in the middle transversely by enlarged parts or flanges, within which
enlarged parts is formed a circular chamber for the before-mentioned disc or oscil-
lating plunger to work in. On the inner face of each head of the casing there is
cast a cylindrical portion, projecting inwards as far as the disc, and in combination
with these cylindrical portions there are partitions which separate the inlet from the
outlet port of each set, and project inwardly to the inner ends of the said cylindrical

page_text: portions. These partitions enter slots made for their reception on diametrically
opposite sides of the before-mentioned scroll plunger.
The motion of the scroll plunger is controlled by two or more guiding discs situate
in the sides of the central enlarged chamber, there being studs or pins on the sides
of the central disc or oscillating plunger near its periphery, which engage into cor-
responding holes in the said guiding discs.
The actuating eccentric or cam herein-before referred to is slotted radially on one
side, so as to fit a squared and lateral projecting portion or crank on the driving
shaft, a helical or other spring being interposed between the end of the said crank
and the inner end of the slot in the eccentric, which allows the eccentric a limited
play or movement on the squared portion or crank of the driving shaft.
The two suction or inlet pipes may or may not be united at any desired point,
and have thus a single pipe through which the water will be drawn; and it is also
preferred to unite in like manner the two outlet pipes.
The suction pipe being connected with the water supply, and the shaft rotated in
the proper direction, the water will be drawn in through the two opposite inlet
ports, and expelled through the two opposite outlet ports, since by the peculiar
oscillating motion of the scroll plunger there will be a constant suction at the inlet
ports alternately within and on the outside of such plunger, and at the same time a
constant forcing of the water at the outlet ports, this pressure being exerted alter-
nately by the contraction of the space within the plunger and that between such
plunger and the shell of the pump.
No air chamber is required with this pump.

page_text: two or more pins d', which set into holes in guide wheels or discs F¹. The guiding
discs are made of the required size, and are set into the sides of the enlarged portions
of the shell within the chamber d. I have shown in the Drawing only two of these
guiding discs, one on each side of the disc F, and on diametrically opposite sides of
the pump, but it is preferred in practice to use six of the said guiding discs, three
on each side.
For lubricating the working parts of the pump the chamber d is partly filled with
oil through a plug in the top of the shell, and the disc F by moving around in
this chamber keeps its frictional surfaces well oiled. A number of holes d³ are bored
through the disc F from its periphery to the central opening, in which the eccentric
works, and such eccentric is thereby kept lubricated from the oil in the chamber d
Any impurities or any water which may get into the chamber d is worked by the
disc F into the bottom of such chamber, and can be carried off through a pipe d
With the disc F is cast a scroll plunger H, projecting on each side of such disc,
and abutting water-tight against the heads B, B', this plunger is composed of two
cylindrical wings e, e', having rectangular slots f, f, which extend from the outer
ends of the wings into the disc F; these slots are placed diametrically opposite each
other, the slot in the wing e being in the upper side of its wing, whilst the slot f¹
is in the lower side of the wing e².
In the lower part of the head Bare formed two ports (inlet and outlet) I, I', which
are separated from each by a partition g; this partition projects inwardly to the
inner end of the cylinder C, and from such cylinder extends to the shell of the
pump, dividing the annular chamber G at this point, and projecting into the slot f
of the plunger; these ports are connected with suction and force pipes, not shown in
the Drawings. The bead B¹ is provided with a similar partition g', and like inlet
and outlet ports K, K³, situated near the upper periphery thereof, and having water-
conveying pipes similar to those connected with the ports I, I'.
The two suction pipes may be united at any proper point, and have a single pipe
through which the water will be drawn. It is also preferred, in constructing this
pump, to join the two outlet pipes, and lead therefrom a single pipe for delivering
the water at the desired place.
A spring packing / may be placed on the side of each of the internal cylinders,
just inside of the inlet ports, to prevent back pressure, but this packing may be
dispensed with.
The suction pipe being connected with the water supply, and the shaft turned in
the direction shown by the arrows, the water will be drawn in the ports I, K, and
forced from the ports I¹, K', since, by the peculiar oscillating motion of the scroll
plunger, there will be a constant suction at the inlet ports alternately within and
on the outside of such plunger, and at the same time a constant forcing of the water
at the outlet ports, this pressure being exerted alternately by the contraction of the
space within the plunger, and that between such plunger and the shell of the
pump.
While on one side of the disc F the plunger is throwing but a small stream, the
opposite side of the plunger will be exerting its greatest pressure (shown in dotted
lines, Figure 5); and both outlet pipes being joined as above described, these
pressures may be so graduated that a constant stream will be ejected without the
use of an air chamber to equalize the flow.
Should any small obstruction get between the scroll plunger and the shell, or
between such plunger and the inner cylinders, the eccentric would move upon the
spring c, and allow the plunger to pass over the obstruction.
The pump constructed as above described is very simple in construction, has no
valves which are expensive to replace or keep in repair, and requires but little
packing. In its operation there is no back pressure, and consequently no leakage;
and the scroll plunger having a constant forward motion, there is no waste of power
in overcoming the momentum of the plunger, as in ordinary pumps. There is also
no friction of the parts, except at the outer ends of the plunger, where it rubs against
the heads, and on the side of the disc F, at the points in contact with the extended

page_text: portion of the shell, so that the inside of the pump can be covered with vulcanized
india-rubber or other substance to prevent corrosion, thus adapting the pump for
use in pumping out mines and other like places.
Having now described and particularly ascertained the nature of the said
Invention and the manner in which the same is or may be used or carried into
effect, I would observe in conclusion that what I consider to be novel and original,
and therefore claim as the Invention secured to me by the herein-before in part
recited Letters Patent is,-
First. In an oscillating pump I claim the scroll plunger H, substantially as
described.
Secondly. The combination of the scroll plunger and an eccentric shaft for
operating the same, substantially as and for the purposes set forth.
Thirdly. The combination with the scroll plunger of the disc F for dividing the
cylinder of the pump into two parts, substantially as and for the purposes set
forth.
Fourthly. The combination with the shell of the pump of an oscillating plunger
and two sets of inlet and outlet ports, arranged substantially as described and
shown.
Fifthly. The combination of the shell A, A³, heads B, B', and cylinders C, C¹, cast
in two pieces, substantially as described and shown.
Sixthly. The combination with the shell, heads, and internal cylinders of the
eccentric disc F, slotted plunger H, inlet and outlet ports, and partitions g,g³, sub-
stantially as described and shown.
Seventhly. The squared portion 6 of the shaft in combination with the slotted
cam E and spring c, substantially as described and shown.
Eighthly. The combination with the scroll plunger of the eccentric for operating
the same, and the guiding discs for controlling its motion, substantially as and for
the purpose set forth.
In witness whereof, I, the said Adolph Rommel, have hereunto set my hand
and seal, this Thirtieth day of May, in the year of our Lord One thousand
eight hundred and seventy-eight.