Year: 1888

page_text: Date of Application, 11th Aug., 1888
Complete Specification Left, 13th Apr., 1889
• Complete Specification Accepted, 6th June, 1889
I CHARLES DARRAH of Miller Street, Manchester, Manufacturer do hereby declare
the nature of my said invention to be as follows :-
These improvements are applicable more particularly to inlet ventilators and have
for their object first the providing of a means whereby to visibly indicate even to
strangers unacquainted with the arrangement of the ventilator whether the ventilator
is open or closed.
In performing my invention and as applied to that class of inlet-ventilator con-
taining a flap mounted upon pivots one of which is extended through the casing to
the outside and there has a knob affixed for operating the flap, my improvements
consist in forming an opening through the casing and which is glazed with trans-
parent glass. Affixed to the flap are a pair of plates, one marked with the word
open and the other with the word "closed"-these plates being so mounted upon
the flap as to come up opposite to the glazed opening and so to indicate the position
of such flap whether open or closed.
The improvements are also applicable to ventilators containing a sliding plate similar
to a damper for opening and closing the communication with the outer atmosphere
and also to outlet-ventilators if it be desired to indicate whether the same are open
or closed.
Secondly this invention refers to the means employed for straining or filtering the
incoming current of air and so as to prevent the entrance of dust or other like
impurities along therewith.
These consist of a metallic frame mounted in any convenient part of the ventilator
casing in a similar manner to a damper and over which frame textile fabric, wire
gauze or other suitable straining material is distended. Or the sliding frame may
consist of a pair of plates or grating hinged or otherwise secured together and so
capable of having a layer of wool or other suitable straining material supported

page_text: between them and thus to act as the filtering medium. This sliding frame so
arranged as aforesaid is capable of being withdrawn from time to time so as readily
to remove any dust or other impurities adhering thereto or to introduce new straining
material.
The straining media so disposed and supported as hereinbefore described may be
of a disinfecting nature or may be saturated with a disinfecting liquid or with any
desired perfume.

page_text: 1 CHARLES DARRAH of Miller Street, Manchester, Manufacturer, do hereby declare
the nature of my said invention and in what manner the same is to be performed
to be particularly described and ascertained in and by the following statement :-
These improvements are applicable more particularly to inlet ventilators and have
for their object first the providing of a means whereby to visibly indicate even to
strangers unacquainted with the arrangement of the ventilator whether the ventilator
is open or closed.
In Fig. 1 I illustrate a front view and in Fig. 2 a side sectional view of an inlet
ventilator embracing my improvements. Fig. 3 is a front and Fig. 4 a plan view on
an enlarged scale of the flap employed in Figs. 1 and 2 and shewing the improved
indicators attached.
This ventilator contains the ordinary flap a mounted upon pivots b one of which is
extended through the casing c to the outside and there has a knob d affixed for operating
the flap in the ordinary manner. My improvements consist in forming an opening e
through the casing c and which is by preference glazed with transparent glass.
Affixed to the flap a are a pair of plates ƒ and g the one platef bearing the word
"open" and the other plate g being similarly marked with the word "shut." These
plates seen separately in Figs. 3 and 4 are mounted upon the flap a so as to revolve with
and come up opposite to the glazed opening e and in this manner indicate the position
of the flap a whether it is open or closed.
The improvements are also applicable to outlet ventilators if it be desired to indicate
whether the same are open or closed and to ventilators the flaps of which are pivoted
in the direction of the length of the flap-the position of the indicator plates being
modified accordingly.
Secondly this invention refers to the means employed in inlet ventilators for straining
or filtering the incoming current of air and so as to prevent the entrance of dust soot
or other like impurities along therewith.
These improvements are also indicated in Figs. 1 and 2 and consist of a pair of
plates or gratings and i hinged or otherwise secured together as seen also in plan
view (on an enlarged scale in) Fig. 5. and so capable of having a layer of wool or other
suitable straining material supported between them and thus to act as the filtering
medium. This frame so arranged as aforesaid is capable of sliding into its recess
(formed in any convenient part of the casing) like a drawer and of being withdrawn
from time to time so as readily to remove any dust soot or other impurities adhering
to the filtering medium or to introduce new straining material. Or the sliding drawer
may consist of a metallic frame j as indicated in side sectional view Fig. 5* the top k
and bottom of this frame being formed of textile fabric wire-gauze or net-work or
other suitable straining material and enclosing between them loose cotton wool or other
suitable filtering material.

page_text: The straining media so disposed and supported as hereinbefore described may be of
a disinfecting nature or may be saturated with a disinfecting liquid or with any desired
perfume.
Having thus particularly described and ascertained the nature of this my said
invention and in what manner the same is to be performed I declare that
what I claim is :-
1st. The improved means of indicating the position of the pivoted flap of a ventilator
substantially as hereinbefore described.
2nd. In the construction of a ventilator the employment of indicating plates secured
to the flap in combination with a glazed orifice in the casing substantially as and for
the purpose herein before described.
3rd. In an inlet ventilator the employment of a sliding drawer or frame enclosing
wool or other filtering or straining media substantially as and for the
before described.
purpose
herein-
Dated this 12th day of April 1889..
JOHN G. WILSON,
Patent Office,
55, Market Street, Manchester,
Agent for the Applicant.