IMPROVEMENTS IN THE CONSTRUCTION OF BLOWERS FOR FORCING AIR
Year: 1875

page_text: PROVISIONAL SPECIFICATION left by Richard Russell Gubbins at the
. Office of the Commissioners of Patents, with his Petition, on the
- 30th December 1875.
I, RICHARD RUSSELL GUBBINS, of Upper Thames Street, in the City
of London, Civil Engineer, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN THE CONSTRUCTION OF BLOWERS FOR FORCING
AIR," to be as follows:-
My Invention of improvements in blowers for forcing air relates to
that kind of blower in which the air is drawn in at the centre or other
convenient part of the apparatus, as in ordinary fans, and is forced
forward with a positive pressure in contradistinction to the slight
pressure produced by driving the blades of the ordinary fan at a very
high speed, and consequently at the expenditure of a very considerable
amount of motive power.
.
My improved blower consists of a metal casing cast in two parts, pro-
vided with flanges and connected together by screws or otherwise, the

page_text: cross section of the capacity of the casing presenting the form of two
radial sections of a flat thin circular disc placed transversely to the
casing.
The blade or blades (there may be two) of the fan are of corre-
sponding form, and are produced by cutting out radially from the centre
to the circumference of a flat circular disc of suitable dimensions
sections, one or more of which are secured by the wide curved edge
to the rotating central axle of the blower. The surface of this rotating
axle, instead of being cylindrical, is curved in a longitudinal direction to
correspond to the curve of the blade.
Thin circular metal discs are arranged transversely across the casing
(in which transverse slots are made for the purpose) so that the edges
of the circular discs may correspond or coincide with the longitudinal
curve of the central axle. A radial section is cut out of the flat circular
discs, corresponding in size to the dimensions of the fan blade, the two 1
parts being so arranged that the fan blade may pass through the radial
spaces that are cut out of the circular discs.
Rotary motion is communicated to the circular discs by means of
suitable gearing connected with the central axle of the blower, so that
the speed of all the parts may correspond in order that the radial spaces 2
cut out of the circular discs may always be brought into the proper
position to allow the fan blade to pass through.
Sometimes I mount the fan blade or blades diagonally on the shaft, in
which case the superficial area of the blades will be greater than that
of the radial spaces cut out from the circular discs. These latter are 2
enclosed in a case which is secured to the case of the blower so as to
render the whole apparatus as air-tight as possible.
I would also remark that the circular discs and fan blades should be
fitted as accurately as possible to the blower casing so as to avoid
leakage of the air, but must not be allowed to touch, otherwise a great 3
amount of friction will be created.
The air is drawn in at the centre or other convenient part of the
casing, and is drawn (by the fan blade) out of apertures situated in front
of the rotating circular dises.

page_text: From the above description it will be understood that the circular
discs, although always rotating, will present a firm and solid abutment
for the air to press against, except at the radial spaces provided for the
passage of the fan blade or blades, and consequently the air will be
forced out of the casing with a positive pressure corresponding to the
size of the blower and the speed at which the blades are driven.