Improvements in Rotary Pumps.
Year: 1898

page_text: Date of Application, 25th Oot., 1898-Accepted, 7th Jan., 1899
COMPLETE SPECIFICATION.
Improvements in Rotary Pumps.
I, ROBERT PAUL VOIGT, of Kleine Borstel, Hamburg, in the German Empire,
Manager, do hereby declare the nature of this invention and in what manner
the same is to be performed, to be particularly described and ascertained in and
by the following statement:-
The present invention relates to valveless pumps with rotating pistons in which
in a casing or cylinder connected by suitable passages with an admission pipe and
an outlet pipe two pistons are arranged and alternately actuated by a stud working
in a pear-shaped cam groove in the cylinder cover. The actuating stud is secured
to a rotative arm which may be driven either by hand or by steam power.
The invention is illustrated in the annexed drawings in which
Figure 1 shows a front elevation of the pump, the cover plate being removed.
Figure 2 is a vertical section through the pump.
Figure 3 is a front elevation of the pump and the outside mechanism complete.
Two wings or pistons e, f are arranged tightly fitting the internal surface of
the casing or cylinder a, the latter being tightly closed by a cover plate band
provided with an admission and exhaust openings c and d, respectively. Packing
strips of elastic material are suitably fitted to the wings or pistons e and f. The
axles, to which the pistons e and f are fastened, are arranged one inside the other;
they are indicated in the drawings by el and f¹ respectively. Packing material or
rings may be employed to ensure tight fitting. Arms e² and f are fast to the
axles e and f¹ respectively. A handle h may be employed for actuating the said
axles. For this purpose the handle his fitted with a movable arm i terminating
in a stud k which latter works in a cam groove provided in the cover plate b.
A pawl n under the influence of a spring m retains always one of the two arms
fitted to the axles of the pistons. The outlet branch is preferably provided with
an air vessel o and a closing cap p.
The improved pump operates in the following manner:-
Assuming the cylinder to be filled with liquid when the organs of the pump
are in the position indicated in Figures 1 and 3; on turning the handle h, the
movable arm will release the pawl n and catch the operative arm e, whereas
it will not come in contact with the second operative arm 2, the latter being
so situated as to be within the extent of the cam surface and not in the path of
the stud k in the cam groove l. As above described the piston e partakes in the
movement of its operative arm e², closes the admission c and presses by virtue of
the volume of liquid contained in the cylinder in front of it, the piston f into
the position which the piston e started from. The piston f will now be arrested
in this position by the pawl n. Meanwhile the outlet d has been opened, so that
the liquid can escape. The piston e having travelled about seven-eighths of a
revolution, it will assume the position occupied by the piston f in Figure 1.
operative arm e² of the piston e will now be situated in the lobe caused by the
The

page_text: extension of the cam. On further turning the handle h the operative arm fa
will be caught and the action of the pump as described will repeat itself.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the sanie is to be performed, I declare that what I
claim is :-
1. In a pump with rotating pistons having the two pistons loosely mounted
inside the casing or cylinder and provided with operative armis, the latter being
alternately caught by a movable arm having a stud working in a cam groove in
the cylinder cover.
2. In combination with a pump with rotating pistons of the class specified, the
axles for the two pistons arranged one within the other and each provided with
an operative arm outside the cylinder, substantially as set forth.
3. In combination with a pump with rotating pistons of the class specified, a
cam groove formed in the cylinder cover, with a lobe to enable the operative arms
of the pistons being caught and actuated alternately, substantially as set forth.
4. A pump with rotating pistons constructed and operated substantially as
described and shewn in the accompanying drawings.
Dated the 25th day of October 1898
PHILIPS & LEIGH,
No. 22, Southampton Buildings, Chancery Lane, London, W.C.,
Agents for the Applicant