Grates of Steam Generator Furnaces.
Year: 1886

page_text: Date of Application, 29th July, 1886.
Complete Left, 28th Apr., 1887.
Complete Accepted, 31st May, 1887.
Grates of Steam Generator Furnaces.
I, NEVILLE EVANS, of Woodstock, Waterloo, in the County of Lancaster, Engineer
do hereby declare the nature of my said invention to be as follows:-
:―
My Invention has for its object to provide means whereby the inconveniences
accompanying many of the systems employed for obtaining artificial draught under
the grates of steam generator furnaces is obviated. Such inconveniences exist for
instance where steam jets are employed in that they create objectionable noises, again
in the case of steam ships, what are known as closed stoke holes are also objectionable
in many respects, such as the want of free and ready access to, or egress from them.
Many means of obtaining artificial draught necessitate by their use a large monetary
expenditure and my Invention has for its object to obviate in degree the necessity of
so large an expenditure.
According to my Invention, I employ an upward directed jet, or number of jets of
preferably heated air in the funnel, or shaft of the steam generator, such jet, or jets of
air being created by suitable fan blowing apparatus making little noise. The single
jet is arranged concentrically, or annularly in the funnel. When a number of jets
are used they may be arranged in the funnel circumferentially or they may be
grouped.
An advantage attending the use of my Invention is that the larger the power of
the steam generator, the smaller the expenditure necessary in proportion.

page_text: Grates of Steam Generator Furnaces.
I, NEVILLE EVANS, of Woodstock, Waterloo, in the County of Lancaster, Engineer
do hereby declare the nature of my said invention and in what mannor the same is to
be performed, to be particularly described and ascertained in and by the following
statement
My Invention. has for its object to provide means whereby the inconveniences
accompanying many of the systems employed for obtaining artificial draught under
the grates of steam generator furnaces is obviated. Such inconveniences exist for
instance where steam jets are employed in that they create objectionable noises, again
in the case of steam ships, what are known as closed stoke holes are also objectionable
in many respects, such as the want of free and ready access to, or egress from them.
Many means of obtaining artificial draught necessitate by their use a large monetary
expenditure and my Invention has for its object to obviate in degree the necessity of
so large an expenditure.
According to my Invention I employ an upward directed jet, or number of jets of
preferably heated air in the funnel, or shaft of the steam generator, such jet, or jets
of air being created by suitable fan blowing apparatus making little noise. The
single jet is arranged concentrically, or annularly in the funnel. When a number of
jets are used they may be arranged in the funnel circumferentially or they may be
grouped.
The above being the nature, object and purposes of my Invention, I will now
proceed to particularly describe, with the aid of the accompanying two sheets of
Drawings suitable and convenient arrangements and constructions according to my
Invention for use in connection with marine steam generators. The Drawings are
marked with figures and letters of reference corresponding with those used in the
following explanation. Like letters of reference are used to denote like, or
corresponding parts throughout the various views and figures.
Figure 1 in the accompanying Drawings is a sectional elevation of a funnel of a
marine steam generator having a centrally arranged jet therein.
Figure 2 is a plan in section through X X Figure 1.
Figure 3 is a sectional elevation of an annular central jet.
Figure 4 is a sectional elevation of a funnel having a number of jets arranged
circumferentially.
Figure 5 is a plan of same.
In the Drawings A designates the funnel and B the jet, or jets. With reference to
Figures 1 and 2 the funnel is contracted above the jet B by a plate C as shown and
the mouth of the jet is of slightly greater diameter than the main portion. The jet B
is held in position by vertical webs, or diaphragms a. D is the air pipe, or lead from

page_text: the fan which I prefer to place over the boiler, or other. like part so as to ventilate
and keep the stoke hold as cool as possible.
In Figure 3 the jet B is in the form of an annular nozzle and is provided with a
tapered conical body b to diminish eddying.
It will be obvious that the air in passing towards the exit, or mouth will be heated
and thereby will prevent a too rapid cooling of the uptake gases as they come in
contact with the air.
The arrangement shown in Figures 4 and 5 illustrate a funnel of a steam generator
having a number of nozzles, or jets circumferentially disposed therein. In this case
there is provided a casing, or jacket E round the funnel. The air is heated in this
jacket by the hot surface of the funnel before being delivered into and up the funnel
and is supplied by a fan in the manner above set forth with reference to Figures 1
and 2 through the pipe D. The nozzles, or jets B are secured to the funnel and
communicate with the upper part of the jacket E by apertures cut in the funnel.
An advantage attending the use of my Invention is that the larger the power of
the steam generator, the smaller the expenditure necessary in proportion.
I would have it understood that this Invention is applicable to all kinds of shafts
or funnels of steam generators and is not confined to the examples herein set forth.
Having now particularly described and ascertained the nature of my said Invention
and in what manner the same is to be performed, I declare that what I claim is :—
First. The herein described means of obtaining draught under the grates of steam
generator furnaces, which consists essentially of a jet, or jets of air produced by a
fan, or fans and directed upwardly in the funnel of such steam generator whereby a
partial exhaustion is effected above the fuel on such grates.
Second. The parts herein described arranged and combined with the funnel
substantially as set forth with reference to the Drawings.