An Improved Spark Arrester, Smoke Consumer, and Draught Producer.
Year: 1898

page_text: Date of Application, 9th May, 1898-Accepted, 6th Aug., 1898
COMPLETE SPECIFICATION.
An Improved Spark Arrester, Smoke Consumer, and Draught
Producer.
I, JAMES SHEPHERD, of 54, Lambton Quay, Wellington, New Zealand, 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 follow-
ing statement:-
This invention relates to devices used for arresting sparks and consuming
smoke from steam boilers and its object is to provide apparatus which may be
readily affixed to existing boilers and be effective in arresting sparks and consum-
ing a considerable proportion of the smoke.
The invention as carried out in the form which is preferred consists of a driving
fan operated by the exhaust steam to revolve one or more fans which withdraw the
products of combustion from the smoke box and force the same into the funnel
where they meet the exhaust steam after it has been utilized in operating the
driving fan. Sparks drawn into the fans are extinguished by the fans or after
escaping therefrom in a partially extinguished condition are finally extinguished
by the exhaust steam. The draft in the funnel is regular since the action of the
fans is to draw an even and constant stream of hot gases from the smoke box.
The fire has thus a regular and constant draft with a resulting improved fire and
better consumption of smoke.
In order that the invention may be most easily understood reference will be
made to the accompanying drawings, which illustrate the invention as applied to
the smoke box of a locomotive boiler.
Figure I is a sectional elevation of a locomotive smoke box fitted with the
invention.
Figure II is a cross section of the same on line A-B, Figure I.
Figure III is an exterior side view of the same.
Figure IV is a cross section of the funnel on line C-D, Figure I.
Similar letters of reference indicate corresponding parts throughout the views.
Referring to the views, the smoke box (a) has an exhaust pipe (a) fitted with
a driving fan (b) and connected to the funnel (c) by airtight joints. The shaft (61)
of fan (6) extends upon each side and carries fans (d), in the casings (d) of which
are bearings (³). Ball bearings are preferred to reduce friction as much as
possible, and to facilitate adjustment, or roller bearings may be used if desired.
The products of combustion are drawn from the smoke box into the fans (d)
through apertures (a2) made in the side of the said smoke box, and after passing
through the fans the said products are driven up the pipes (3) to the base (c) of
the funnel (c) where they meet the exhaust steam after it has been utilized in
operating the driving fan (b). The products of combustion and the exhaust steam
after striking the baffle plate (f) which is perforated with holes (f¹) pass out of
the funnel (c).
A byepass (9) may be opened by operating regulating valve (g) from the foot-
plate by any ordinary means connected to the-shaft (2), to allow some of the whole
of the exhaust steam to pass. This is necessary when the exhaust steam is

page_text: driving the fans at too great a speed, or in case the fans should get out of order.
The engine would thus not be disabled in case of the apparatus failing to operate.
When the engine is standing the products of combustion pass through the fan
casings (d) and up the pipes (3) to the funnel.
The chamber (72) of the fan (b) is made with a gradually increasing radius to
leave an increasingly widening space (63) between the periphery of the fan and the
casing (62) and to prevent the steam from being carried round by the fan.
The vanes (d) of fans (d) are shaped as shewn on Figure II to lessen the noise
made by ordinary fans when revolving at a high speed.
It is obvious that pipes may be conducted from the pipes (3) to the fire box
and a portion of the hot gases utilized for increasing the combustion of the fuel.
Where the exhaust steam cannot be employed to operate the fans, the fans (d),
may be revolved by means of pulleys and a belt driven from the engine shaft, or
by any other suitable means.
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. In combination with the smoke box of an engine a driving fan operated by the
exhaust steam of the engine apertures in the smoke box fans for withdrawing the
products of combustion from the smoke box pipes for conveying the said products
to the funnel an exhaust pipe fitted airtight between the steam chest and the
funnel, substantially as and for the purposes set forth herein.
2. In combination with the smoke box of an engine a driving fan operated by
the exhaust steam of the engine apertures in the smoke box fans for withdraw-
ing the products of combustion from the smoke box pipes for conveying the said
products to the funnel an exhaust pipe fitted airtight between the steam chest
and the funnel and a byepass, substantially as and for the purposes set forth
herein.
3. In combination with the smoke box of an engine a driving fan operated by
the exhaust steam of the engine apertures in the smoke box fans for withdrawing
the products of combustion from the smoke box pipes for conveying the said pro-
ducts to the funnel an exhaust pipe fitted airtight between the steam chest and
the funnel a byepass and a regulating valve in the byepass, substantially as and
for the purposes set forth herein.
4. In combination with the smoke box of an engine a driving fan operated by
the exhaust steam of the engine apertures in the smoke box fans for withdrawing
the products of combustion from the smoke box pipes for conveying the said pro-
ducts to the funnel an exhaust pipe fitted airtight between the steam chest and
the funnel a baffle plate in the funnel a byepass and a regulating valve in the
byepass, substantially as and for the purposes set forth herein.
Dated INGUA love at
A
1908
ROBERT E. PHILLIPS, Assoc. M. Inst. C.E., M.I. Mech. E.,
Consulting Engineer, and Patent Agent,
70, Chancery Lane, London, W.C., Associate Agent.