IM- PROVEMENTS IN VENTILATORS AND SMOKE EXTRACTORS
Year: 1871

page_text: PROVISIONAL SPECIFICATION left by Robert Boyle at the Office of the
Commissioners of Patents, with his Petition, on the 27th January
1871.
I, ROBERT BOYLE, of Glasgow, in the County of Lanark, North
Britain, do hereby declare the nature of the said Invention for "IM-
PROVEMENTS IN VENTILATORS AND SMOKE EXTRACTORS," to be as follows:-
This Invention comprises various improvements in ventilators and
smoke extractors, which improvements have been devised whilst working
out an Invention for which the present applicant has already obtained
Letters Patent, dated 28th July 1870 (No. 2120.)
One modification of ventilator made with the present improvements
consists of a separate structure, which is illustrated in Figure 2 of the
accompanying Drawings, for leading a current of fresh air from outside
into the interior of a house, ship, chamber, or enclosed space, and to act
either alone or in concert with an extractor ventilator, illustrated in
Figure 1 of the Drawings, fitted in connection with the same space by
leading in a current from the external atmosphere to produce the out-

page_text: Patent above referred to) are placed at the bottom of the shaft 1
opposite the inlet pipe 14, to act more efficaciously on the foul air or
smoke in the tubes or passages 15.
.
A combined modification of Figures 1 and 2 is illustrated in Figure 3
of the Drawings. The uptake shaft 1 is here shown as projecting
through and above the conical rim 21, and the cap 19. The vertical
division plates 20 however are similarly arranged as in Figure 1, the
external air passing between these and infringing on the conical surface
formed by the rim 21 is deflected upwards through the concentric space
between the cap 19 and the top of the uptake shaft 1, and in passing
across the top of the same acts very efficiently in extracting the smoke
or foul air from the shaft. By curving the upper part of the shaft 1
with its mouth facing horizontally or nearly so into the interior of the
conical rim 21 as shown, and covering this by a disc of talc suspended
by platinum wires x, any fall of sparks or down draught in the shaft 1
is effectually prevented, as the more the air. presses in from above the
closer the disc y is pressed against the mouth of the same, but it allows
of the speedy exit of the slightest up current from the shaft 1. In this
case the outlet as dotted would correspond to the top of the shaft 1;
3 is the vertical shaft or tube as in Figure 2, but is made larger to
encircle the uptake shaft 1, and d, d, represent the division plates; 10 is
a small gutter to carry off any rain by the small ducts or pipes 11 to
the roof of the house. Or the rain may be prevented from entering the
shaft 3b by means of the rim 22 or sliding jacket a¹ working against
friction rollers 6', and operated by cords c¹. This jacket is likewise used
to control the supply of air similar to the valve 22 in Figure 2; 3* is
the inlet cone for the uptake shaft 1, and 5* the spreader for distributing
the fresh air over a larger area. It may however as in Figure 2 be
conveyed by pipes or passages to any place where required, and may
also be made to assist the updraught in the shaft 1.
The top of the shaft 1 in some cases is or may be provided with four
hollow extensions or projections 1, 2, 3, 4, (Figure 4) (cross placed), by
which means the outer air is made to exert a greater extracting action
on the smoke or foul air in the shaft. The cross projections perforate
the conical rim 21 as shown in dotted lines at x, x, x, x, in the
isometrical projection Figure 5, so that the rim bears alternately
against the top of the shaft and the bottom of the vertical part of one
of the projections.

page_text: The division plates 20 are also placed (as shown in red in Figure 5)
alternately against the rim (as at m, m, m, m,) and against one of the
cross extensions as at o, o, o, o, and on these plates the cap 19 (shown
in purple in Figure 5,) is placed. The cap is cut away in such a manner
as to leave an equal space between itself, the top of the shaft, and the
cross projections all round, see Figure 4. The top of the shaft may be
made entirely cross shaped, as dotted at p, p, p, p, in Figure 4, and the
cover likewise altered as dotted at r, r, r, r.
Inclined plates arranged polygonally may be substituted for the
conical rims or cones described as part of these modification.
It will readily be seen that in all these modifications the same
principle is strictly adhered to, and that the disposition of the component
parts of the apparatus in every case is as nearly as possible similar.