An Improvement in Blast Apparatus for Furnaces.
Year: 1897

page_text: PROVIDIUNAL SPECIFICATION.
An Improvement in Blast Apparatus for Furnaces.
We, BENJAMIN HOWARTH THWAITE, of 29, Great George Street, Westminster,
in the County of London, Civm Engineer, and FRANK LACROIX GARDNER, of 32,
Old Jewry, in the City of London, Mining Engineer, do hereby declare the nature
of this invention to be as follows:-
For many furnace purposes an air blast is required at a higher pressure than
can be obtained by means of a fan, and consequently recourse is often had to
reciprocating air forcing pumps which working at a comparatively low speed,
require to be of large size occupying considerable space. This invention relates to
means of obtaining a large volume of air blast at considerable pressure, by simple
apparatus of moderate size. For this purpose, two or more fans, which may be
all on the same shaft or may be separately driven--are connected together in
order, each adding to the pressure of the air discharged from that which precedes
it, until the discharge from the last of the fans is of the pressure desired. A
convenient arrangement of fans to act successively on the same air current is as
follows. The first fan which draws from the atmosphere, discharges into a
receptacle in which the air is at pressure somewhat above atmospheric; the
second fan draws from this receptacle and discharges into another, in which the
pressure is still higher, and from which a third fan may draw if still higher pres-
sure of blast is required.
Dated this 19th day of Narambar 1807
ABEL & IMRAY,
Agents for the Applicants.
An Improvement in Blast Apparatus for Furnaces.
We, BENJAMIN HOWARTH THWAITE, of 29, Great George Street, Westminster,
in the County of London, Civil Engineer, and FRANK LACROIX GARDNER, of 32,
Old Jewry, in the City of London, Mining Engineer, do hereby declare the nature
of this invention and in what manner the same is to be performed to be parti-
cularly described and ascertained in and by the following statement:―
For many furnace purposes an air blast is required at a higher pressure than
can be obtained by means of a fan, and consequently recourse is often had to
reciprocating air forcing pumps, which, working at a comparatively low speed,
require to be of large size occupying considerable vertical space.

page_text: This invention relates to means of obtaining a large volume of air blast at con-
siderable pressure, by simple apparatus of moderate size.
For this purpose, two or more fans, or blowers, which may be all on the same
shaft or may be separately driven, are connected together in order, each adding
to the pressure of the air discharged from that which precedes it, until the dis-
charge from the last of the fans is of the pressure desired.
We shall describe by way of example apparatus according to our invention in
which three blowers are arranged to operate, referring to the accompanying draw-
ings.
Fig. 1 is a front view and Fig. 2 is an end view. A¹A³ A³ are three blowers
arranged in a row, and driven, either, as shewn, by belts on separate pulleys, or
it might be by pulleys on a shaft common to them all. B and B are two recep-
tacles arranged so that the blower A which receives air from the atmosphere dis-
charges into B₁, that the blower A2 receives air from the receptacle B and dis-
charges into B2 and that A³ receives air from B3 and discharges it into the blast
pipe C. By this arrangement the pressure in B¹ is raised above that of the atmo-
sphere, the pressure in B2 is farther raised and. the pressure in the blast pipe C is
still farther raised. As the air thus raised by successive stages in pressure, has
its density correspondingly increased, the second blower A³ is of less capacity
than A¹, and A³ is of less capacity than A2.
The blowers employed may be of any suitable known kind, or, instead of
blowers, fans of any suitable known kind can be employed.
For moderate pressures two blowers or fans with one intermediate receptacle
may be used, and for high pressures, more than three blowers or fans with cor-
responding receptacles may be employed.
Having now particularly described and ascertained the nature of this
invention and in what manner the same is to be performed, we declare that what
we claim is :-
Blast apparatus for furnaces comprising two or more blowers with intermediate
receptacles arranged and operating substantially as described.