CERTAIN IMPROVEMENTS IN SPRINGS FOR DOORS AND OTHER PURPOSES
Year: 1833

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ANDREW
SMITH, of Princes Street, Leicester Square, in the County of Middlesex,
Machinist, send greeting.
WHEREAS His present most Excellent Majesty King William the Fourth,
by His Royal Letters Patent under the Great Seal of Great Britain, bearing
date at Westminster, the Fourth day of October, in the fourth year of His
reign, did, for Himself, His heirs and successors, give and grant unto me, the
said Andrew Smith, His especial licence, full power, sole privilege and autho-
rity, that I, the said Andrew Smith, my executors, administrators, and assigns,
or such others as I, the said Andrew Smith, my executors, administrators, or
assigns, should at any time agree with, and no others, from time to time and
at all times during the term of years therein mentioned, should and lawfully
might make, use, exercise, and vend, within England, Wales, and the Town
of Berwick-upon-Tweed, my Invention of "CERTAIN IMPROVEMENTS IN SPRINGS
FOR DOORS AND OTHER PURPOSES;" in which said Letters Patent is contained a
proviso that I, the said Andrew Smith, under my hand and seal, shall cause
a particular description of the nature of my said Invention, and in what
manner the same is to be performed, to be inrolled in His said Majesty's
High Court of Chancery within six calendar months next and immediately
after the date of the said in part recited Letters Patent, as in and by the
same, reference being thereunto had, will more fully and at large appear.

page_text: NOW KNOW YE, that in compliance with the said proviso, I, the said
Andrew Smith, do hereby declare that the nature of my said Invention, and
in what manner the same the same is to be performed, is particularly described
and ascertained in and by the following description thereof, reference being
had to the Drawings hereunto annexed, and to the figures and letters marked
thereon (that is to say) :-
My Improvements in Springs for Doors and other Purposes apply to the
construction springs applicable to the closing of doors and casements of
windows that open horizontally, or to other situations where such springs may
be required, which improvements.consist in a peculiar form and novel adapta-
tion of a spring or springs and levers which, when attached to a door or
casement, will cause that door or casement to close and remain closed. The
accompanying Drawings exhibit the construction of the spring, and its appen-
dages as adapted to a swinging door.
Figure 1 is an elevation of the lower part of a door with the box containing
the spring shewn sideways, as let into the floor. Figure 2 is a back view of
the same. Figures 3 and 4 are horizontal views of the box containing the
spring and levers, the upper plate being removed. Figure 5 is a vertical
section of the box taken in the same direction as Figure 1. a, a, is the box
or metallic case which encloses the springs and levers. 6 is the centre pin
upon which the door turns (shewn by dots in Figure 5).. This pin is firmly
secured to the bottom of the box by a nut and screw or other fastening. c, c,
is a metallic shoe fixed on to the heel of the door by screws or other con-
venient means. A centre piece d, formed square at the top part, and having
a recess or inverted cup at its lower part, is secured into a socket in the shoe by
"a screw and washer or otherwise. Upon the centre piece d, bearing upon the
pin b, as a pivot or hinge, the door turns when opening or shutting. From
the side of the piece d an arm or lever e extends, having an antifriction roller
at its end acting against the internal surface of a pair of bent levers f,f,
shaped as callapers, which levers turn upon a hinge joint formed by the pin g
screwed into the bottom of the box a. These levers are pressed together by
one or more circular or crescent-formed springs i, i, i, the ends of the springs
bearing with considerable tension against the sides of the levers f, f, and when
the levers are in a quiescent state, as in Figure 3, their extremities rest
against the stop h, which is the position of the parts when the door stands
closed, or as shewn by dots A, A, in that Figure. The operation of the spring
is as follows: When the door or casement is closed, the spring and levers
remain in the quiescent state last described; but on the door being swung

page_text: either backwards or forward, the end of the arm or lever e is made to act
upon one of the levers f, forcing its extremity away from the stop piece h, as
shewn in Figure 4. The spring i by these means becomes expanded, and its
tension being thereby increased when the door is let go the spring i imme-
diately begins to collapse, and its ends acting with great force against the
backs of the levers f, f, presses them together. The force thus exerted
through the spring i, upon the levers ff, causes the internal parts of the
curved surfaces of those levers to force the arm e back again into the position
shewn in Figure 3, and consequently to bring the swinging door, which is
connected with this arm e and centre piece d, into the closed position, as
shewn by dots in the last-mentioned Figure. When it is desired that the
spring should be made to keep the door or casement standing open, it
is only necessary to move the arm or lever e a sufficient distance to carry
the centre past the end of the lever f (that is, into the position shewn by
dots B in Figure 4), when the spring will cause the end of the lever f to
press against the antifriction roller, and confine the arm e in that position, and
consequently keep the door open. The spring can be at any time brought
into action to close the door by moving or returning the door sufficient to
bring the centre of the arm e within the end of the lever f. It is necessary
to remark that the top part of the door must be furnished with a centre pin
and socket upon which it can turn freely, and that such pin should be in per-
pendicular coincidence with the pivot d, d, below. It will be perceived that
the force of the spring i may be increased or diminished by shifting the posi-
tion of its ends further from or nearer to the centre pin g of the levers f, f,
for which purpose it may be desirable to form grooves or notches in the
backs of the levers f, f, suited to receive the ends of the springs; and the
spring i may be made of any suitable strength, or several circular or crescent-
formed springs may be combined togather in the way shewn. One important
feature connected with this construction of apparatus for closing doors or case-
ments consists in adapting springs without any fixed fulcrum, as it will be
perceived that they are held solely by their tension and pressure upon the
levers ff, and consequently being thus free, every part of the circular or
crescent-formed spring is brought into elastic operation.
In witness whereof, I, the said Andrew Smith, have hereunto set my
hand and seal, this Fifth day of April, in the year of our Lord One
thousand eight hundred and thirty-four.
ANDREW (L.S.) SMITH.

page_text: AND BE IT REMEMBERED, that on the Fifth day of April, in the
fourth year of the reign of His Majesty King William the Fourth, the said
Andrew Smith came before our said Lord the King in His Chancery, and
acknowledged the Instrument aforesaid, and all and every thing therein con-
tained, and specified in form above written. And also the Instrument afore-
said was stamped according to the tenor of the Statute made in the fifty-fifth
year of the reign of His late Majesty King George the Third.
Inrolled the Fifth day of April, One thousand eight hundred and thirty-