IMPROVEMENTS IN VENTILATORS
Year: 1877

page_text: LETTERS PATENT to Rober Boyle, senior, of Glasgow, in the County of Lanark,
North Britain, Ventilating Engineer, for the Invention of "IMPROVEMENTS
IN VENTILATORS."
PROVISIONAL SPECIFICATION left by the said Robert Boyle at the Office
of the Commissioners of Patents on the 7th November 1877:
ROBERT BOYLE, senior, of Glasgow, in the County of (Lanark, North Britain,
Ventilating Engineer. "IMPROVEMENTS IN VENTILATORS."
This Invention relates to improvements, in ventilators, whereby such apparatus
is rendered more simple in construction and efficient in action or results than
heretofore.
Under one modification or arrangement, as applicable for attachment to the top
of a tube or shaft to be ventilated, the ventilator casing is preferred to be of a
vertical quadrangular shape in outline, made of sheet metal, but open vertically at
the four corners and at the central position of each of the four sides, opposite which
side openings vertical partitions are placed, the four inner edges or ends of which
terminate a short distance from the vertical centre line of the ventilator, thus
leaving the centre open and forming current directors, at the same time dividing
the ventilator into four vertical compartments or spaces, within each of which is
arranged or formed an inner vertical quadrangular chamber or space, the four
sides of which are in turn fitted with stationary vertical vanes or apertures, with
or without straight, angular, inclined, or curved deflecting plates for inducing out-
ward ventilating currents from within by the force of the outer deflected air
currents. These apertures may be V or U shaped in horizontal section, or the apex
of the V or U may be open, or as it were cut away, leaving free access for the
outrush of foul air from within.
If preferred, however, the inner quadrangular chambers or spaces may have from
one to sixteen apertures, or more, as occasion may require, and for some purposes

page_text: two or three instead of four of these quadrangular chambers or spaces may be
sufficient, the order of arrangement or construction of the external casing being
the same or triangular for three, and the whole fitted or surmounted with an
ordinary conical or other suitably shaped crown or top.
By another improvement instead of narrow vertical outlet slits with or without
the angled or curved side inducing plates, herein-before described, rows of round
or oval holes may be fitted in the inner shell, with short angled or trumpet-shaped
inducing tubes soldered or otherwise fitted thereto, so that the current of the outer
air, passing through the space between the outer case or baffle plates and this inner
case, would draw the ventilating current from the inside out through the trumpet
tubes fitted in the inner case.
The outer plates, and surface of the inner case, and space between them for the
outer inducing air current, may all be made segmental instead of straight, as herein-
before described.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Robert Boyle in the Great Seal Patent Office on the 4th May
1878.
ROBERT BOYLE, senior, of Glasgow, in the County of Lanark, North Britain,
Ventilating Engineer. IMPROVEMENTS IN VENTILATORS."
My said Invention relates to improvements in ventilators or ventilating hoods
or cowls for attachment to the tops of tubes or shafts z, carried up above the roofs
of houses from the apartments of these, or from common sewers, or from ship holds,
mines, or other places for the ventilation thereof, by drawing the foul air up
through them, whereby such ventilating apparatus is rendered more, simple in
construction and efficient in action and results than as heretofore constructed and
used.
And in order that the nature, novelty, and mode of performing my said Invention
may be properly understood, I shall now proceed to describe the several Figures on
the accompanying Sheet of Drawings, which I have hereunto appended for that
purpose; the same reference letters indicating the same or equivalent parts in all
the Figures where seen.
Figures 1, 2, and 3 are respectively a vertical elevation, and corresponding
section, and horizontal section taken near the lines 1 - - - 1 and 2---2, each on the
other, of one form or construction of my new or improved ventilator or hood, being
the form I prefer, namely, square in the horizontal section of the outer case or body
part A, Figure 3, and rectangular in the elevations, Figures 1 and 2, with a close
internal flat top A', surmounted by an outer conical or other equivalent ornamental
top A to carry the rain off, and having a round or other equivalent hollow neck
socket or stem A² below, widening up by angled or conical sides A³ to the lower
edge of the outer case A, and an internal or false bottom A fitted with four
square holes in it, and corresponding internal tubes, ducts, or cases B, leading up

page_text: therefrom to the close top A', and up and out through which neck and ducts A², B,
the ventilation takes place, all as will be herein-after described.
Figures 4 to 9 are horizontal or transverse sections of other simple polygonal
or round outline forms of my new or improved ventilating hood, with fewer or
more of the internal take-up tubes B than is shown in Figure 3, as with two, three,
and six, seven, and eight, respectively.
Referring to Figures 1 to 3 this ventilator has the outer casing A formed of sheet
metal, and preferably of a vertical quadrangular shape or configuration, but made
open vertically up the four corners a and at the central position a' of each of the
four sides A, A, A, A, by narrow parallel slits or openings á and a¹. Opposite each
side opening a¹, and some little distance back therefrom, a vertical vane or
partition is placed, forming a current director, the four inner edges or ends a²
of which terminate a short distance from the vertical centre line of the ventilator,
thus leaving current openings at their inner and outer ends, at the same time
dividing this central part of the ventilator into four vertical compartments or
spaces as between the upper and lower internal ends A¹ and A1, within each of
which is arranged or formed an inner and rather smaller vertical quadrangular
chamber or duct B, indicated by the four small internal squares B in Figure 3,
formed with vertical slits or openings b up each of their four sides leading into the
centre of their outer current surrounding spaces a³, and which are preferably fitted
with straight vertical angular or curved directing or deflecting plates b², for
inducing outward ventilating, currents from within through the vertical slits or
openings 6 by the force of the outer lateral air current passing in through the
spaces a³ between the outer case A and inner ducts B, which are open up through
the bottom A1 from 'the neck A², all as indicated by the arrows in the several.
sections, Figures 3 to 9. These directing vanes and apertures 6, 6', may be of a
simple V or U shape in horizontal section, as seen in the detached section, Figure 4,
or truncated with the apex of the V or U open, or, as it were, cut away, as seen
in the other sections, Figures 5 to 9, in each case leaving free access for the outward
rush or current of foul air from within, all as stated and indicated by the arrows.
In looking at Figure 3 it will be seen that with four inner up-take ducts B, and
one opening in each side, there would be 16 outlet slits, and with two angled
directing vanes 6', as shown, fitted in each side B there is 48 outlet ventilating slits
or openings b for the drawing out of the foul air from the interior by the lateral
action of the outer air current passing through the openings or channels a³, left all
round between the inner up-take ducts B and the outer case A.
Each main quadrangular chamber A, A, A, A, may have from two to sixteen
inner up-take apertures B, or even more, as may be desired; Figure 4 shows a
diamond-shaped one, and Figure 5 a rectangular one, both with two internal
polygonal up-take ducts B; Figure 6 shows a triangular shaped hood with three
internal triangular up-take ducts B, and Figures 7 and 8 show polygonal sided
hoods with six and seven, internal up-take ducts B, while Figure 9 shows a round
hood with eight internal up-take ducts B, the outer sides of which, as well as that
of the outer case A, are segmental in outline, and although the adjacent sides of
these cases A, B, in Figures 6 to 8; are shown as flat from the polygonal form of
the outer case, still it will be seen that they may be made segmental when the outer
case A is preferred to be made cylindrical, as shown in Figure 9; and as the
elevations of all the forms of hoods shown in the horizontal sections, Figures 4 to 9,
would be much the same as that shown in Figures 1 and 2, it is not necessary to
show the elevations of these in the Drawings, and each of these hoods would be
formed with a short inlet neck socket or spigot piece A³, as seen in Figures 1 and 2,
for shipping it on to the up-take pipe or stalk z leading from the chambers, pipes,
common sewers, or other place to be ventilated by the lateral action of the outer
air currents induced through the through-and-through ducts a¹ between the inner
sides of the outer case A and the outside of the inner up-take ducts B, all as
described and indicated by the arrows in the several Figures.
In some case the edges of the plates A, as indicated at all in Figure 4, and

page_text: openings a of the through-and-through outer air inducing channels a¹ may be
curved outwards in a trumpet form for the better ingress and egress of the outer
air and inner ventilating currents.
By another improvement, instead of the narrow vertical outlet slits b, with or
without the angled or curved inside inducing plates b¹, herein-before described, a
few vertical rows of round or oval holes may be fitted or formed through the centre
of the sides of the inner shells or ducts B, either fitted or not as desired with short
angled or trumpet-shaped inducing tubes, soldered or otherwise fitted in the holes,
so that the current of the outer air passing through the spaces a² between the outer
case A or baffle plates a" and the inner case B would draw the ventilating current
from the inside out through the holes or their trumpet tubes fitted in the inner
case B, otherwise substantially as described in reference to Figures 3 to 9.
Having now described the nature of my said Invention, and the manner of
performing the same, I have to state that I do not confine myself to the precise
details herein described or delineated, but what I consider novel and original, and
therefore claim as the Invention secured to me by the herein-before in part recited
Letters Patent is,.
First. The general construction or combination of the parts of a ventilating hood
or apparatus, substantially as herein described in reference to and shown in the
accompanying Drawings; or any mere modification thereof.
Second. The construction and use of ventilating hoods with two or more internal
up-take ducts B, with central opening b leading into narrow through channels
a, a¹, a¹¹, between their own sides and that of the outer casé A for the ingress and
egress of the outer acting air, all substantially as herein described in reference to
and shown in the accompanying Drawings, or any were modification thereof.
In witness whereof, I, the said Robert Boyle, senior, have hereunto set my
hand and seal, this Third day of May; in the year of our Lord One thousand
eight hundred and seventy-eight.
Witness,
W. R. M. THOMSON,
Patent Agent,
Glasgow.
ROBERT BOYLE, SEN". (L.S.)