AN IMPROVED RATCHET REGULATOR FOR WINDOW BLINDS, VENTILATORS, FANLIGHTS, MIRRORS, AND OTHER LIKE PURPOSES
Year: 1875

page_text: LETTERS PATENT to Alexander Melville Clark, of 53, Chancery Lane,
in the County of Middlesex, Patent Agent, for the Invention of
"AN IMPROVED RATCHET REGULATOR FOR WINDOW BLINDS, VENTILATORS,
FANLIGHTS, MIRRORS, AND OTHER LIKE PURPOSES." -A communication
from abroad by John T. O'Donoghue, of the City, County, and State
of New York. United States of America.
PROVISIONAL SPECIFICATION left by the said Alexander Melville
Clark at the Office of the Commissioners of Patents, with his
Petition, on the 11th May 1875.
I, ALEXANDER MELVILLE CLARK, of 53, Chancery Lane, in the
County of Middlesex, Patent Agent, do hereby declare the nature of
the said Invention for "AN IMPROVED RATCHET REGULATOR FOR WINDOW
BLINDS, VENTILATORS, FANLIGHTS, MIRRORS, AND OTHER LIKE PURPOSES," to be as
follows:-
This Invention consists of a ratchet wheel and a spring pawl or break

page_text: readily as is required for shifting the slats of a window blind, ventilator,
or register, as also for opening and closing revolving fanlights, venti-
lators, car windows, and for adjusting a pivoted mirror, and will be held.
fast by the spring alike whether turned one way or the other, the wheel
being a pivot of the slat or other object to be adjusted, and the spring
being on the frame in which the pivot turns, or in a case forming the
bearing of the pivot, and attached to the frame, having a recess in which
the case is fitted flush with the surface or nearly so. This latter arrange-
ment is the most preferable, because the pivot case and spring can all be
combined in one contrivance ready to be attached by connecting the
pivot to the object to be turned, and fitting the case in the recess in the
frame.
For connecting the pivot it is provided with a clip of thin metal
adapted to fit the end and sides of a slat or the edge and two sides of the
frame of a mirror, fanlight, window, or the like.
°
The teeth of the ratchet wheel are shaped alike on both sides, and the
spring is also contrived so that it presents the same form to the teeth
whichever way they turn, being in the form of an obtuse angle with
curved sides, the apex of which is the point acting on the wheel, and
the ends of the spring being attached to the case; but I do not limit
myself to the exact form of spring here described, nor to one having
both ends attached to the case, for a suitably shaped point at the free
end of a spring having only one end attached may be used with good
results.
SPECIFICATION in pursuance of the conditions of the Letters Patent, 2
filed by the said Alexander Melville Clark in the Great Seal Patent
Office on the 27th September 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ALEXANDER
MELVILLE CLARK, of 53, Chancery Lane, in the County of Middlesex,
Patent Agent, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Eleventh day of May, in the year of
our Lord One thousand eight hundred and seventy-five, in the thirty.
eighth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Alexander Melville Clark, Her special 3

page_text: licence that I, the said Alexander Melville Clark, my executors, adminis-
trators, and assigns, or such others as I, the said Alexander Melville
Clark, my executors, administrators, and assigns, should at any time
agree with, and no others, from time to time and at all times thereafter
during the term therein expressed, should and lawfully might make, use,
exercise, and vend, within the United Kingdom of Great Britain and
Ireland, the Channel Islands, and Isle of Man, an Invention for "AN
IMPROVED RATCHET REGULATOR FOR WINDOW BLINDS, VENTILATORS, FANLIGHTS,
MIRRORS, AND OTHER LIKE PURPOSES," a communication to me from abroad
by John T. O'Donoghue, of the City, County, and State of New York,
United States of America, upon the condition (amongst others) that I,
the said Alexander Melville Clark, my executors or administrators, by
an instrument in writing under my, or their, or one of their hands
and seals, should particularly describe and ascertain the nature of the
said Invention, and in what manner the same was to be performed,
and cause the same to be filed in the Great Seal Patent Office within
six calendar months next and immediately after the date of the said
Letters Patent.
NOW KNOW YE, that I, the said Alexander Melville Clark, do hereby
declare the nature of the said Invention, and in what manner the same is
to be peformed, to be particularly described and ascertained in and
by the following statement, reference being had to the accompanying
Sheet of Drawings, and to the letters and figures marked thereon (that
is to say):-
This Invention consists of a ratchet wheel and a spring pawl or brake
contrived in such manner that the wheel may be turned either way
readily as is required for shifting the slats of a window blind, ventilator,
or register, and also for opening and closing revolving fanlights, venti-
lators, car windows, and for adjusting a pivoted mirror, and will be held.
fast by the spring alike whether turned one way or the other, the wheel
being on a pivot of the seat or other object to be adjusted, and the spring
being on the frame in which the pivot turns, or in a case forming the
bearing of the pivot, and attached to the frame, having a recess in which
the case is fitted flush with the surface or nearly so. This latter arrange-
ment is the most preferable, because the pivot case and spring can all be
combined in one contrivance ready to be attached by connecting the
pivot to the object to be turned, and fitting the case in the recess in the
frame.

page_text: 3rd. The combination of the clip E, pivot D, ratchet wheel A, and
spring pawl or brake B, substantially as specified.
In witness whereof, I, the said Alexander Melville Clark, have
hereunto set my hand and seal, this Twenty-seventh day of
September, in the year of our Lord One thousand eight hundred
and seventy-five.