IMPROVE- MENTS IN VENTILATORS
Year: 1862

page_text: PROVISIONAL SPECIFICATION left by Joseph Kitchin at the Office of
the Commissioners of Patents, with his Petition, on the 28th August
1862.
I, JOSEPH KITCHIN, of Liverpool, in the County of Lancaster, Ventilating
Engineer, do hereby declare the nature of the said Invention for "IMPROVE-
MENTS IN VENTILATORS," to be as follows (that is to say):-
This Invention has for its object the construction of a convenient form of
ventilator for withdrawing the vitiated atmosphere from churches, domestic
chambers, concert-rooms, or other buildings, and introducing a supply of
fresh air thereinto. A ventilator to be applied to (say), the roof of a building
constructed according to this Invention may consist of a vertical, cylindrical,
or other suitably shaped pipe, the upper end being formed with an enlarged
flanched lip extending downwards, and the lower end being formed with a
trumpet mouth and surrounded with a suitable perforated guard suspending
a hollow disc having its concave side downwards. This shaft extends below
the interior of the roof of the building a given distance. This shaft is sur-
rounded from the roof upwards by an octagonal or other suitably shaped
casing slightly tapering towards the top, and of sufficient capacity to form a
chamber or passage between the outer surface of the first described vertical
shaft and the inner side of the outer casing, forming a passage for the egress
of the foul air which escapes between the upper edge of the outer casing and
the curved enlarged flanche or lip of the inner shaft in a downward direction.

page_text: The shaft and its outer casing is surmounted by a dome or other suitably
shaped cap, which in the case of an octagonal outer casing is supported by
eight brackets or trusses springing from the angles thereof, and is internally
divided by vertical partitions into four equal compartments, and this cap being
formed of a greater diameter, and having its lower edge extending downwards
to an horizontal line with the lower edge of the turned lip of the vertical
shaft (or thereabouts), forms the passage by which the fresh air enters and
decends the vertical centre air shaft through the perforated guard into the
The internal or fresh air shaft is fitted with a throttle valve, which
can be regulated by a cord carried over pulleys or by rods and bars, or in
any other convenient way. I prefer to weight the valve, so that it will remain
open when not acted upon through the cord or other gear; the foul air
passage formed between the vertical shaft and the outer casing is also fitted
with valves or ports, so that the whole or any portion of the passage may be
closed or opened at pleasure by means of a system of cords and pulleys, or in
any other convenient way. The lower end of the outer casing immediately
below the roof is surrounded by a funnel or trumpet-mouthed lip, and which
on the under side is enclosed by wirework or a suitable perforated plate. The
lower edge of the dome or cap may also have lateral perforations formed
therein for the admission of air. In some cases it is preferred to form a
spiral channel round the outer surface of the fresh air shaft for catching the
moisture arising from condensation which is conducted away through a
suitable passage.