Improvements in Inlet Ventilators.
Year: 1886

page_text: PROVISIONAL SPECIFICATION.
Improvements in Inlet Ventilators.
I JOHN ALEXANDER MACMEIKAN of 2 Short Street Finsbury Pavement. London
E.C. Ventilating and Sanitary Engineer do hereby declare the nature of this invention
to be as follows:-
I place upon the mouth of an inlet Ventilating tube where it opens into the
apartment radiating plates dividing the mouth transversely into sections and preferably
in two directions at right angles to each other so that the opening at the lower end of
the plates is considerably less than at the upper and the whole forms an expanding
head with radiating compartments. The spaces between the compartments are
arranged so that those more nearly parallel to the line of the tube are closer together
than those forming more of an angle with it, so as to equalise the distribution of the
Draught. The mouths of the compartments next the room are preferably covered with
perforated material in order still further to distribute and slacken the Draught. I
form the valve in the tube wholly or in part of perforated material so as not to entirely
check but merely slacken the Draught when closed.
JUHN А. МАСМЕТКАМ.
COMPLETE SPECIFICATION.
Improvements in Inlet Ventilators.
1 JOHN ALEXANDER MACMEIKAN of 2 Short Street Finsbury Pavement London
E.C. Ventilating and Sanitary Engineer 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 :—
I place upon the mouth of an inlet ventilating tube where it opens into the
apartment radiating plates dividing the mouth transversly into sections and preferably
in two directions at right angles to each other so that the opening at the lower end of
the plates is considerably less than at the upper and the whole forms an expanding
head with radiating compartments. These compartments may also be formed by the
The spaces
juxtaposition of inverted cones or funnels of metal or thin material.
between the several compartments, however formed, are arranged so that those more

page_text: nearly parallel to the line-of-the-tube-are-closer-together-than-those-forming more of
an angle with it so as to equalise the distribution of the Draught, inasmuch as the air
passing up the tube meets with more resistance from the more oblique plates and
consequently requires more area to make up for the obstruction to its speed. By this
means perfect equality can be obtained in the velocity of current passing through each
compartment and the area of the upper end of the head being three or four or more
times that of the lower end next the tube the velocity of the incoming Draught can by
means of such an apparatus as I have so far described be slackened three four or more
times so as to be almost imperceptible, and by this means any dust or blacks which
may enter the tube from the outside have not sufficient velocity to be carried into
the room and are deposited on the sides of the apparatus, rendering unnecessary
any canvas bags or other devices for arresting dirt.
The mouths of the compartments at the upper end of the head next the room
may be covered with perforated material in order still further to distribute and
slacken the Draught this is the more necessary when the radiating plates are very
short owing to want of space or other circumstances.
I preferably form the valve in the tube wholly or in pari of perforated material
so as not to entirely stop but merely slacken the Draught so that it cannot be felt
when the valve is closed.
1 use in combination with the above a special outside grating having baffle plates
behind it by which rain is prevented from driving through as shewn in Fig. 8
and so placed that the harder the wind blows the more resistance is offered and sudden
puffs into the room are wholly avoided.
Referring to the drawings here to annexed; Fig. 1 shews the radiating plates or
head on an inlet tube placed against a flat wall.
Fig. 2 shews the same on an inlet tube placed in a corner.
Fig. 3 shews the radiating head alone.
Figs. 4 & 4 shew the radiating head in two sections at right angles to each other.
A. A. are the radiating plates in each case placed at unequal intervals according to
their obliquity.
Figs. 5. 6 & 7 shew the radiating head in form of an ornamental bracket for flat
wall, & corner respectively the last being in section shewing the valve open and the
whole fixed with outside grating complete.
Fig. 8 shews the outside grating in front elevation and section respectively. B. B. are
the baffle plates above mentioned.
Having now particularly described and ascertained the nature of my said Invention,
and in what manner the same is to be performed, I declare that what I claim is:
1. The arrangement of Inlet Ventilator tubes having expanding heads with radiating
plates dividing the same transversely in two directions at right angles to each other &
either in the form of inverted cones or otherwise and covered with perforated material
or otherwise substantially as described.
'
2. The arrangement of such radiating plates with unequal spaces so that those more
nearly parallel to the line of the tube are closer together than those forming more of
an angle with it substantially as described.
3. The use in Inlet Ventilators of valves made wholly or in part of perforated
material.
4. The use in combination with Inlet Ventilators of a grating with baffle plates
substantially as described.
5. The combination of all the arrangements claimed to form an improved Inlet
Ventilator.
JOHN A. MACMEIKAN.