AN IMPROVED LEVER COMPENSATION DOOR AND GATE SPRING OR CLOSER.
Year: 1869

page_text: LETTERS PATENT to James Blair Nimmo,, of No. 8, North Bank Street,
Edinburgh, of the Firm of P: and J. Nimmo, Brassfounders there,
for the Invention of "AN IMPROVED LEVER COMPENSATION DOOR AND
GATE SPRING OR CLOSER.".
Scaled the 29th October 1869, and dated the 3rd May 1869..
PROVISIONAL SPECIFICATION left by the said James Blair Nimmo at
the Office of the Commissioners of Patents, with his Petition, on
the 3rd May 1869.
I, JAMES BLAIR NIMMO, of No. 8, North Bank Street, Edinburgh,.
of the Firm of P. and J. Nimmo, Brassfounders there, do hereby declare
the nature of the said Invention for "AN IMPROVED LEVER COMPENSATION.
DOOR AND GATE SPRING OR CLOSER," to be as follows:-
This Invention consists of a new and improved apparatus for using,
applying, and working the weight in compensation door and gate springs,
as herein-after described.
The apparatus employed by me is shewn on the Drawing annexed, and
may be thus further described. Two levers D, D, act in gear with a

page_text: bevelled or other wheel or pinion C, and both rest on centre
bearings G, G, G, and operate by means of compensation balance weight
or weights E, E, suspended from the said two levers. The top of the
spindle of the pinion C, is squared, and on this is fitted an iron strap A,
which supports the door or gate, and which is attached in the usual
way. The spindle F and pinion or wheel C are best made in one piece
but may also be made separately and keyed together. The whole is
fitted into a cast-iron case or frame B, which is fitted into and flush with
the floor.
What I claim as of my Invention in the apparatus above described
is my new and improved apparatus or appliance for using, applying, and
working the weight or weights in the manner above described.
One of the advantages of my improved apparatus is, that the weight
has the same pull or tension throughout the turn of the door or gate,
and this is equally as strong when the door or gate is fully opened as
it is when closed.
Another advantage is that there is almost no possibility of the
apparatus breaking or getting out of order.
The Invention may be made of various sizes to suit the weight of the
door or gate and the size of the weights used.
Having thus explained the nature of my improvements I wish it
to be understood that I do not confine myself to the exact details
described, but I claim the said Invention substantially as and for the
purpose herein-before set forth.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said James Blair Nimmo in the Great Seal Patent
Office on the 2nd November 1869.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JAMES BLAIR
NIMMO, of Number Eight, North Bank Street, Edinburgh, Scotland, of
the Firm of P. and J. Nimmo, Brassfounders there, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Third day of May, in the year of
our Lord One thousand eight hundred and sixty-nine, in the thirty-
second year of Her reign, did, for Herself, Her heirs and successors give

page_text: and grant unto me, the said James Blair Nimmo, Her special licence
that I, the said James Blair Nimmo, my executors, administrators, and
assigns, or such others as I, the said James Blair Nimmo, 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
LEVER COMPENSATION DOOR AND GATE SPRING OR CLOSER," upon the condition
(amongst others) that I, the said James Blair Nimmo, 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 James Blair Nimmo, do hereby
declare the nature of my said Invention, and in what manner the samo
is to be performed, to be particularly described and ascertained in and
by the following statement (reference being had to the Drawing hore-
unto annexed and to the letters and figures marked thereon), that is to
say:-
This Invention consists of a new and improved apparatus or con-
trivance for using, applying, and working the weight in compensation
door and gate springs as herein-after described.
The apparatus or contrivance employed by me is shewn on the
Drawing annexed, and may be. thus further described. Two levers
D, D, act in gear with a bevelled or other wheel or pinion C, and
both rest on centre bearings G, G, G, and operate by means of
compensation balance weight or weights E, E, suspended from the said
two levers. The top of the spindle of the pinion C is squared, and on
this is fitted an iron strap A, which supports the door or gate and which
is attached in the usual way. The spindle F and pinion or wheel C
are best made in one piece, but may also be made separately and keyed
together. The whole is fitted into a cast-iron case or frame B, which
is fitted into and flush with the floor.
What I claim as of my Invention in the apparatus or contrivance
above described is, my new and improved apparatus, or contrivance, or

page_text: combination for using, applying, and working the weight or weights in
the manner above described.
I have further to explain that I do not claim as of my Invention
any particular portion of the apparatus above described, but what I do
claim as of my Invention is, the combination of the different parts and
actions herein-before described as and for the purpose described, and also
the application of the bevelled or other pinion, acting with levers and
weights as herein-before described.
One of the advantages of my improved apparatus or contrivance is,
that the weight has the same pull or tension throughout the turn of the
door or gate, and this is equally as strong when the door or gate is fully
opened as it is when closed.
Another advantage is that there is almost no possibility of the
apparatus breaking or getting out of order.
The Invention may be made of various sizes to suit the weight of the
door or gate, and the size of the weights used.
Having thus explained the nature of my Invention, and in what
manner the same is to be performed, I wish it to be understood that I
do not confine myself to the exact details described, but I claim the
said Invention substantially as and for the purpose herein-before set
forth.
In witness whereof, I, the said James Blair Nimmo, have here-
unto set my hand and seal, this Fifteenth day of October,
in the year of our Lord One thousand cight hundred and sixty-
nine.
JAMES BLAIR NIMMO. (L.S.)