An Improved Chimney Cap or Cowl.
Year: 1892

page_text: Date of Application, 19th Feb., 1892
Complete Specification Left, 21st Nov., 1892-Accepted, 21st Jan., 1893
PROVISIONAL SPECIFICATION.
An Improved Chimney Cap or Cowl.
I, JOHN TAYLOR LEIGHTON of 18 Montgomery Street, Edinburgh, Gentleman
do hereby declare the nature of this invention to be as follows:-
The object of my invention is to provide by simple and efficient means against
and to secure the prevention of "down draught" in chimneys. The device which
I employ consists of two parts or members. That is to say; the top of any
ordinary chimney can has, adapted thereto, vertically, a short extension piece
forming a "neck" for the reception of and around which shall be free to rotate,
what I herein designate the "cowl-proper." This latter comprises a chamber of
cylindrical or other suitable shape, open at both ends. It is disposed horizontally,
relatively to the chimney top or can, and has below, a collar, fitting around the
vertical extension piece or "neck" above referred to.
"
The top of the cowl-proper" is provided with a vane of any desired pattern or
design to allow of the former turning with the wind. One end of the "cowl-proper
is of funnel mouth formation, that is to say; in the manner of a truncated cone,
with the open apex thereof extending inwards. Said tunnel mouthed end being
always turned to the wind, the latter on entering the "cowl-proper," blows across
and draws the air, and with it the smoke, up the chimney can, whence these pass
outwards at the front or "lee" end of the "cowl-proper."
Down draught with the nuisance of smoky chimnies, being thus effectually
provided against. The device as above described, serving also as will be readily
understood as an advantageous means of veutilation.
101 1
1000
JAMES STEVENSON,
Gray's Inn Chambers, 20, High Holborn, London, W.C.,
Agent for Applicant.
COMPLETE SPECIFICATION.
An Improved Chimney Cap or Cowl.
JOHN TAYLOR LEIGHTON of 18 Montgomery Street, Edinburgh, Gentleman,
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 :-
The object of my invention is to provide by simple and efficient means, against
and to secure the prevention of "down draughts" in chimneys.
In the accompanying drawing
Figures 1, 2 and 3 represent sectional elevations of a chimney cap or cowl
according to my invention.
The device which I employ consists of two parts or members that is to say the
top of any ordinary chimney can has adapted thereto, vertically, a short extension
piece A forming a neck for the reception of and around which shall be free to
rotate what I herein designate the "cowl proper." This latter comprises a
horizontal chamber B, and a vertical portion B¹.
The extension piece A has a collar a fitted around the bottom end of same as
shown Figs. 2 & 3 or the latter is formed slightly conical or in any other shape to
allow of the cowl resting and turning thereupon as shown in Figure 1 in which
latter case the collar a is dispensed with.

page_text: The top of the cowl proper is provided with any form of usual and well known
vane to allow of the cowl turning with the wind. One orifice C of the cowl proper
is of funnel mouthed formation, that is to say, in the manner of a truncated cone
with the open apex thereof extending inwards. find in practice that it will be
better to place the open apex c of the truncated cone somewhat in rear of the
longitudinal axis of the vertical portion B¹ as inasmuch as the nearer the apex of
the cone approaches the vertical centre, the draught is correspondingly reduced in
the chimney. Said funnel mouthed end being always turned to the wind, the latter
on entering the "cowl proper" blows across the mouth of chimney and draws with
it the smoke up the chimney can whence these pass outwards at the front or outlet
end of the cowl proper.
The cowl is also provided interiorally with any suitable spindle and bearing
device with pivot to allow of free rotation but which however not forming any
distinctive feature of my invention I have not shown same in the drawings.
Down draughts with the nuisance of smoky chimnies being thus by means of my
invention effectually provided against. The device as above described as will be
readily understood is also an efficient means of ventilation. In practice I find it
advantageous to make the vertical extension piece A somewhat contracted, as
shown in the drawings.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I wish it to be under-
stood, I am aware that prior to this invention, rotating chimney tops or cowls have
been constructed of horizontal cylinders open at both ends and with interior inlet
tubes plain and conical and I therefore make no claim per se to such a construction,
but what I claim is.
In chimney or ventilator caps or cowls, the combination with an extension piece,
of the chamber B, B' free to rotate upon the former. The portion B being provided
with inlet orifice C, consisting of a truncated cone, the apex c of which is at or
about or
preferably somewhat in rear of the point of intersection with the vertical
axis of B¹ as lierein set forth.
JAMES STEVENSON,
Gray's Inn Chambers, 20, High Holborn, London, W.C.,
Agent for Applicant.