Improvements for Inducing and Increasing the Draught of Furnaces.
Year: 1890

page_text: Date of Application, 5th Mar., 1890
Complete Specification Left, 5th Dec., 1890-Accepted, 24th Jan., 1891
PROVISIONAL SPECIFICATION.
Improvements for Inducing and Increasing the Draught of Furnaces.
JONATHAN PICKERING "Cranbrook" Torquay Gentleman do hereby declare the
nature of this invention to be as follows:-
These improvements relate to an arrangement of mechanism devised for inducing
and increasing the draught of furnaces, whereby the gases are drawn off by the action
of a screw made to revolve in the flue funnel or chimney, the motion of which is
obtained by steam, air, or driven by power.
The object of these improvements is to create by induction a draught for steam
boilers or other furnaces, so that the flame and heat may be drawn from the fuel to a
greater length than can otherwise be done with either natural or forced draught
producing more effective heat and greater economy of fuel.
The mechanisin consists of a shaft surrounded with a screw or a scroll fixed upon the
said shaft. In addition thereto is a corrugated circular vane formed into a series of
angles, this portion is for the purpose of obtaining rotary motion with the wind or
with steam injected against it, or the shaft referred to may be driven by power.
Another feature of the invention is the bearings for the shaft which are of the
roller description.
JON. PICKERING.
COMPLETE SPECIFICATION.
Improvements for Inducing and Increasing the Draught of Furnaces.
1, JONATHAN PICKERING, of "Cranbrook," Torquay, Gentleman, do hereby declare
the nature of my said invention and in what manner the same is to be performed, to
be particularly described and ascertained in and by the following statement :-
The improvements relate to an arrangement of mechanism devised for inducing
and increasing the draught of furnaces, whereby the gases are drawn off by the action
of a screw made to revolve in the flue, funnel or chimney the motion of which is
obtained by a jet or jets of steam or air or driven by power applied to the shaft.
The object of these improvements is to create by induction a draught in steam
boiler and other furnaces, so that the flame and heat may be drawn from the fuel to a
greater length than can be done with either natural or forced draught thereby
producing more effective heat and greater economy of fuel.
The mechanism consists of a shaft on which is mounted a screw or scroll fixed to
the said shaft. In addition thereto is attached a circular vane for the purpose of
obtaining rotary motion by means of the wind or with steam injected against its
periphery or the shaft may be driven by power.
Another feature of the invention is the bearings for the shaft, which are of the
roller description.
In order that my invention may be fully understood I shall proceed more
particularly to describe the same and for that purpose shall refer to the drawings
accompanying this Specification.
Figure 1 is a section of a funnel or chimney having the screw or scroll shown
therein also the vane at the top as herein described.
Figure 2 is a sectional plan of the vane on the line a. b.
Figure 3 is a plan of the screw on the line c. d.
Figure 4 is a plan of the bearings or guides e with rollers as shown e¹.
Figure 5, 6 and 7 show the foot step used with three or more roller cones as shown
at (f) Fig. 5.
These roller cones (f) are fitted on radiating arms f" as shown on Figs. 6 and 7 to

page_text: keep the cones in their position. The angle of these cones is such that when the
cones are in position their sides radiate as a common centre. These roller and
roller cone bearings are for the purpose of reducing the friction.
I wish it to be understood that I am fully aware that the screw or scroll has been
used for a cowl for domestic purposes for many years but the purpose for which I
claim is different from any such application where the current of air causes the
revolution of the screw whereas in my invention I drive the screw or scroll and thus
induce a current or draught of air.
Having now described and ascertained the nature of my said invention and in
what manner the same is to be performed, 1 declare that what I claim is :-
1st. The application of a screw or scroll to funnels or chimneys and the use thereof
in the manner herein described and illustrated in the accompanying drawings.
2nd. The application of rollers for guide fixings or bearings and roller cones for the
foot-step of the shaft in order to reduce the friction of the same substantially as
described and illustrated by the drawings.
GEO. DOWNING,
8, Quality Court, London, W.C., Agent for Applicant.
GEO. DOWNING,
8, Quality Court, London, W.C., Agent for Applicant.