Improvements in and relating to Rotary Blowers and the like.
Year: 1897

page_text: Date of Application, 30th Jan., 1897-Accepted, 10th Apr., 1897
COMPLETE SPECIFICATION.
Improvements in and relating to Rotary Blowers and the like.
I, DAVID MORELL, of Wilhelmshöher Allee 39, Cassel, in the German Empire,
Blacksmith, 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 :-
This invention relates to a new or improved construction of rotary blower which
may also be used as an air compresser or as a pump for liquids. It is constructed
in such a manner that the rotary pistons with their wings make a better and more
air tight junction with each other and with the cylinders than in existing machines
of the same type, so that it is possible to compress air to several atmospheres and
to elevate liquids under a much greater head or pressure.
I will describe my said invention with reference to the accompanying drawings
in which :-
Figure 1 represents a side elevation, and Figure 2 a plan with the top cover
removed and one of the rotary pistons in cross section. The gearing in this figure
is indicated by dotted lines.
The duplex cylinder a is provided with the outlet o and inlet p. Within it are
arranged the two parallel cylinders d, e, f, g, mounted upon the vertical spindles b, c.
These rotary pistons consist of the cylindrical parts d, e, upon which the wings f, g,
are fixed, three wings being preferably fixed to each cylinder. The wings as well
as the spaces between them are faced or coated with soft leather so that contact is
only made by the leather coated surfaces. The leather may be kept in position by
means of small pins let into the surface or by metallic border strips, and each piece
of leather is preferably embedded in a shallow recess prepared for its reception.
The wings may be fixed to the cylinders by dovetails fitting into dovetailed
grooves, not shown in the drawings, and by set screws such as h. By this method
of construction most of the work can be done on the lathe, which is of importance
with regard to economy and truth. The two pistons are externally geared
together by the wheels l, m, each of which has the same number of teeth, but in
each wheel there are two distinct pitch lines so that the teeth are in as many
segments of large diameter as there are wings, and in as many segments of shorter
radius. By this construction a sliding friction between the vanes is transformed
into a rolling contact, and the power required for driving the system is thereby
reduced. The effect of this construction is also to increase the speed of the rotary
pistons just when the wings bottom the opposite recesses. This gearing is more
especially applicable for large apparatus.
The faces of the wings are concave and the apparatus works in the following
manner-It having been put in rotation, the pistons rotate in opposite directions,
one wing commencing to bottom the opposite recess before the outer surface of the
leading wing has left the bottom of the leading recess. By this arrangement there
is always a tight contact between the two rotary pistons, which will thus not
permit any backward flow of the fluid. This effect is now achieved for the first
time, as in existing apparatus the approach to and recession from the point of
contact by the leading and following wings are simultaneous. According to the
present construction there is always about a quarter of an inch or more of surface
contact between the pistons. This contact is very greatly improved by the presence
of the leather.

page_text: Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. In a rotary blower which may also be used as an air compresser or exhauster
and as a pump, winged rotary pistons faced with leather, so operated that the
larger diameter of one wing commences to bottom the opposite recess before the
preceding wing leaves the bottom of the preceding recess, constructed and arranged
substantially as, hereinbefore described and as illustrated by the accompanying
.drawings.
2. In rotary blowers and the like, connecting the rotary pistons, by means of a
pair of spur wheels each of which has its teeth arranged in segments of different
radii, there being as many segments of large diameter as there wings on one piston,
.for the purpose of increasing the speed of rotation at the moment when the wing of
one piston is fully within the recess of the opposite piston, substantially as
.herein before described and as illustrated by the accompanying drawings.
Dated this 29th day of January 1897.
W. E. HEYS & SON,
Agents for the Applicant.