Improvements in Cowls for Chimneys or Shafts.
Year: 1896

page_text: Date of Application, 25th Jan., 1896
Complete Specification Left, 24th Oct., 1896-Accepted, 28th Nov., 1896
PROVISIONAL SPECIFICATION.
Improvements in Cowls for Chimneys or Shafts.
I, KENNETH BROWN MCKENZIE of No. 43 Rose Street in the City of
Edinburgh N.B. Builder Slater and Contractor, do hereby declare the nature of
this invention to be as follows:-
My invention has for its object to provide for chimneys or shafts an improved
cowl which will increase the up-draught and effectually draw and pass the smoke
or foul air up and from the chimney or shaft and it consists in providing in
combination with a portion of the cowl arranged to rotate on a vertical axis, a fan
or exhauster arranged to rotate on a horizontal axis in the vertically revolving
part. The vertically rotating portion of the cowl may be of any desired shape for
instance it may be cylindrical or rectangular in which latter case two of its sides
may be extended upwards in a triangular or other form. A cross piece at the
upper part of the rotating portion of the cowl carries a vane on which the wind
acts so as to rotate the said rotating part and the edges of the rotating portion of
the cowl may be turned outwards so as to deflect any currents of air tending to
interfere with proper discharge of the smoke or foul air from the cowl. The fan
or exhauster is rotated by currents of air acting on the horizontally arranged
blades of the said fan, by which arrangement of the fan the smoke or foul air is
most efficiently drawn up and discharged from the chimney or shaft. The stationary
portion of the cowl may be constructed to fit onto a chimney pot or with a base to
be built into the chimney stack or shaft or into the roof of a building.
Dated this 25th day of January 1896.
JOHNSONS & WILLCOX,
47 Lincoln's Inn Fields, London, W.C., Agents.
I, KENNETH BROWN MCKENZIE of No. 43 Rose Street in the City of
Edinburgh, N.B. Builder Slater and Contractor, 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:-
My invention has for its object to provide for chimneys or shafts an improved
cowl which will increase the up-draught and effectually draw and pass the smoke or
foul air up and from the chimney or shaft.
Figures 1 and 2 of the accompanying drawings represent, in vertical sections at
right angles to each other a cowl constructed according to my invention and
Figure 3 shews in elevation a modified construction of the cowl.
The cowl shewn in Figures 1 and 2 of the drawing comprises a stationary part A
and a rotary part B, the stationary part A being shewn as cylindrical to fit into or
onto an ordinary chimney pot whilst the rotary part B is shewn as rectangular and
provided with a vertical spindle 6 on which the said part rotates in a tubular

page_text: bearing c carried by the part A the said tubular bearing being provided at its upper
end with a cup or receptacle to contain oil or other suitable lubricant to maintain
the spindle efficiently lubricated. Securely attached to the interior of the rotary
part B is a transverse bar C from which depends the spindle b. Two opposite
sides d of this rotary part of the cowl extend above the other two sides d' and
taper upwards, their upper ends being connected together by a plate or bar fon
which is fixed a vane D on which the wind acts so as to maintain the opening
between the two upwardly extended sides d in line with the direction of the wind.
Arranged to rotate horizontally in bearings in the two sides d is a fan or exhauster E
the blades g of which are acted on by the wind passing through the space between
the upwardly extending sides d so as to cause the fan to rotate, the faces of the
said blades on which the air acts being preferably concave as shewn. The rotation
of the fan or exhauster E has the effect of drawing the smoke up and from the
chimney or shaft. The edges of the extended sides d and also the upper edges of
the shorter sides d' of the rotating portion B are preferably turned outwards as
shewn at h to divert currents of air which might otherwise interfere with the proper
discharge of smoke or air from the cowl. If desired the portion of the cowl in
which the fan or exhauster rotates may be non-rotary and be formed in one with
the part A as shewn in Figure 3. The part A may be provided with a base to be
built into the chimney stack or shaft or for attaching it to the roof or other suitable
part of a building, and the rotating portion instead of being rectangular may be
cylindrical or of other suitable shape.
Having now particularly described and ascertained the nature of my inven
tion and in what manner the same is to be performed I declare that what I
claim is-
1. In cowls, a fan or exhauster arranged to rotate on a horizontal axis by the
wind acting on the blades of the fan substantially as hereinbefore described.
2. The combination and arrangements of parts constituting the improved cowl
for chimneys or shafts substantially as hereinbefore described and illustrated by
Figures 1 and 2 of the accompanying drawings.
Dated this 23rd day of October 1896.
JOHNSONS & WILLCOX,
47 Lincoln's Inn Fields, London, W.C., Agents.