Improvements in and relating to Apparatus for Inducting Air into Furnaces.
Year: 1894

page_text: Date of Application, 16th Oct., 1894-Accepted, 1st Dec., 1894
COMPLETE SPECIFICATION.
COMPLETE SPECIFIOCANELUN
Improvements in and relating to Apparatus for Inducting Air into
Furnaces.
I, JONATHAN MILLS of No. 106 West Sixty-first Street in the City, County and
State of New York, United States of America, Mechanical Engineer, 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 means for facilitating combustion in furnaces and
particularly to that class of devices for the purpose wherein a jet of steam is
employed to induce a current of air to flow to the point of ignition where the
constituent gases of the steam and air combine with the carbon of the fuel.
The object of the present invention is to produce a simple air-induction device or
apparatus having high capacity with facility of access for adjustment, and one in
which the disagreeable noise attendant on the use of such devices is in a good
degree modified.
The invention will be fully described hereinafter and its novel features carefully.
defined in the claims.
In the accompanying drawings-
Figure 1 is a longitudinal mid-section of an air-induction apparatus embodying
my invention.
Figure 2 is an end view of the same.
Figure 3 is a transverse section at line 3, 3, in Figure 1.
Figure 4 comprises an end view and a longitudinal section of one of the steam-jet
nozzles, drawn to a larger scale than the principal views.
Figure 5 comprises two views of other forms of steam-jet nozzles which will be
hereinafter described.
A is the main tube of the apparatus or device. This tube is preferably
cylindrical, but not necessarily so. It may be of cast iron and should have.at
its outer end (at the left in Figure 1) a flange a.
B is the induction nozzle, which may also be of cast iron. This nozzle has an
annular chamber b, formed in its wall and a flange 6x, at its outer end, which when
the nozzle is inserted in the tube A, applies itself to the flange a, to which it is
secured by readily removable fastenings. As here shown these fastenings consist
of bolts and wing-nuts bl.
In the inner end of the nozzle B are set a series of steam-jet nozzles, C, which
communicate with the chamber-b. Six of these steam-jet nozzles, are shown
herein, equally spaced and forming a ring, but the number need not be limited to
six. Steam is admitted to the chamber b, by a nipple 62, which may be coupled by
a union, or otherwise detachably to a steam supply pipe.
is
The preferred form of steam-jet nozzle is illustrated in Figure 4. On a short
section of pipe or tubing, c is screwed a cap ex, in which is formed a central
aperture, c', and cross slits, c², for the escape of the steam. Over this cap c*,
fitted a register cap, c³, which is held in place by screws, c, which engage a
circumferential groove in the inner cap c*. This register-cap has in it a central
aperture which coincides with that in the cap c*, and four apertures c, which may.
be brought to register with the slits in the cap cx ; but by rotation of the register
cap the slits in the cap c* may be partly or wholly closed. The central aperture,
.

page_text: however, will remain open at all times. The screws c¹, serve to fix the register
cap in position when adjusted.
•
The flange and wall of the tube A are cut away at the point where the nipple 6,
enters, so that, when the induction nozzle B is released it may be drawn out to
facilitate the adjustment or repair of the steam-jet nozzles.
To strengthen the hollow wall of the nozzle B it may have cast in it stays, b*,
as seen in Figure 1:
"
It will be seen by inspection that the air-passage, x, through the nozzle B, has a
much smaller area in cross section than the passage y, in the pipe A, beyond the
nozzle B, through which the steam and air, combined, flows on its way to the point
of combustion. This construction provides for the necessary expansion of the
fluids at the point where the steam and air commingle.
The nozzles illustrated in Figure 5 may be employed, especially where adjust-
ment of the adjutage or outlet is not desired. One of these nozzles has only a
central opening or aperture and the other a simple transverse slit, which may
be quite narrow. Other forms of adjutages may be employed.
-
The leading general feature of the construction is the relatively contracted
air-passage, opening concentrically into the larger passage y, at the point where
the ring of steam jets is situated, the said ring of jets surrounding the mouth
of the air-inlet or passage and occupying the annular space formed by the offset,
as clearly shown. The construction which enables the induction nozzle to be
readily removed without disturbing the main tube, which will be secured in
position, and the adjustability of the steam adjutages, are also important features
of the apparatus.
The passage may be extended to, or a little beyond the ends of the steam-jet
nozzles C, as indicated in dotted lines at a in Figure 1. This will serve to lessen
the noise still more than the construction described.
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 :-
:-
1. An air-induction apparatus for furnaces having an air-inlet of relatively
restricted diameter, opening at its mouth into a passage y, of larger diameter than
the air-inlet, an annular offset being thus formed at and laterally exterior to the
mouth of the air-inlet, and steam-jet nozzles arranged at said offset about the
mouth of the air-inlet and in the passage y, whereby an enlarged expansion
chamber is formed from and beyond the point where the steam and air commingle.
2. An air-induction apparatus for furnaces, comprising a main tube having
passage y, an induction nozzle having an air-inlet or passage t, of less diameter
than the passage y and arranged concentrically therewith, and a series of steam-jets
arranged within the passage y and around the mouth of the passage x, sub-
stantially as set forth.
3. An air-induction apparatus for furnaces, comprising a main tube, an air-
induction nozzle B, fitting into said tube and having a chamber b in its wall and
an inlet for steam to said chamber, and a series of steam jets set in the inner
end of the induction nozzle around the air-passage therethrough, substantially as
set forth.
4. An air-induction apparatus for furnaces, comprising a tubular induction
nozzle having an air-passage c, and steam jets C arranged around the mouth of
said passage, and an enclosing tube about said induction nozzle, as set forth.
5. In an air-induction apparatus for furnaces, the combination with the main
tube A, provided with a flange a at its outer end, of the induction nozzle B, adapted
to fit into the tube A and having a flange 6x, and means for detachably securing
the flange 6x to the flange a, whereby the ready removal of the induction nozzle
is facilitated, substantially as set forth.
6. A steam-jet nozzle for an air-induction apparatus, having a cap with adjutages

page_text: for the steam and a rotatable register cap to control said adjutages, substantially as
set forth.
Dated this 15th day of October 1894
WM. P. THOMPSON & Co.,
Agents.