AN IMPROVED MODE OF REGULATING THE MOTIVE FORCE OF SPRINGS APPLICABLE TO ROLLER BLINDS, SWING DOORS, AND EQUIVALENT USES
Year: 1876

page_text: LETTERS PATENT to George Slater, of Dyehouse Buildings, Chiswell Street, in
the County of Middlesex, Machinist, for the Invention of "AN IMPROVED
MODE OF REGULATING THE MOTIVE FORCE OF SPRINGS APPLICABLE TO ROLLER
BLINDS, SWING DOORS, AND EQUIVALENT USES."
Sealed the 1st September 1876, and dated the 23rd June 1876.
PROVISIONAL SPECIFICATION left by the said George Slater at the Office
of the Commissioners of Patents on the 23rd June 1876.
GEORGE SLATER, of Dyehouse Buildings, Chiswell Street, in the County of
Middlesex, Machinist. "AN IMPROVED MODE OF REGULATING THE MOTIVE FORCE
OF SPRINGS APPLICABLE TO ROLLER BLINDS, SWING DOORS, AND EQUIVALENT USES.”
This Invention relates to novel means of controlling the action of coiled springs,
so as to render it unnecessary to use ratchet wheels and pawles or the other
retarding devices at present in use for arresting or checking the action of such
springs when applied to roller blinds, swing doors, and other like uses.
In applying my Invention to a roller blind I fit the case or barrel with a hollow
cone through which the blind spindle passes. This spindle is also fitted with a
cone which enters the hollow cone and is held in frictional contact therewith.
Connected to opposite sides of the hollow cone are two coiled springs of different
sizes and strength, the larger serving to wind up the blind and the smaller by its
pressure to hold the cones together and thereby to lock the blind in any desired
position. A cross pin on the spindle enters between the coils of the small pressure
spring, and as the blind is drawn down the hollow cone, by reason of its attach-
ment to the case, will rotate the small pressure spring and cause it to be wound up
between the cross pin and the cone. This will put a gradually increasing end way
pressure on the cone proportionately to the increased pendent. weight of the blind
as the same is drawn down and cause the cones to bind the more tightly together,
thus the blind whatever its position will have no tendency to rise and be wound
upon the case or barrel until it receives an impetus from below. To provide for
this the blind is weighted at bottom sufficiently to balance the action of the springs,
and on the hand being applied to lift the blind it will receive an upward impulse,
which will cease when that assistance is withdrawn.
By a different adjustment a slow continuous motion of a blind or sheet may be
produced suitable, for example, for a moving panorama or for a slow progressive
inotion in machinery.

page_text: A modification of this controlling apparatus is to form the male cone on a barrel
and mount it loosely on the spindle, the hollow or female cone is in this case made
fast to the spindle, the end of which is to be threaded to receive a travelling nut. This
nut serves to close the end of the barrel and enclose within it a coiled pressure spring.
Projections from the opposite sides of this travelling nut enter slots in the end of the
barrel, which slots prevent the nut from rotating and ensure its travelling on the
spindle as the spindle is rotated. The traverse inward of the nut will compress
the spring and cause it to bind with increasing force the friction cones together, as
in the first example.
This arrangement may be conveniently adapted to swing doors, the barrel being
affixed to either the floor or the lintel, as, thought most convenient. The spindle
will in this case lie in the axis of motion of the door.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said George Slater in the Great Seal Patent Office on the 22nd December
1876.
GEORGE SLATER, of Dyehouse Buildings, Chiswell Street, in the County of
Middlesex, Machinist. "AN IMPROVED MODE OF REGULATING THE MOTIVE FORCE
OF SPRINGS APPLICABLE TO ROLLER BLINDS, SWING DOORS, AND EQUIVALENT USES."
This Invention relates to novel means for controlling the action of coiled springs
so as to render it unnecessary to use ratchet wheels and pawles or the other retard-
ing devices at present in use for arresting or checking the action of such springs
when applied to roller blinds, swing doors, and other like uses.
In the accompanying Drawings I have shown the Invention as applied to a
hollow spring roller such as is employed in connection with holland window blinds.
Fig. 1 shows in longitudinal section a spring roller with its fittings.
A is the ordinary roller made of tin or other sheet metal, and B is the spindle on
which the roller is mounted; C, C, are the bracket bearings for the roller blind;
D is a hollow cone made fast to the interior of the roller, and through it the spindle
B passes;
E is a cone made fast to the spindle B, and made to fit the hollow cone D,
in order that by friction of contact it may temporarily connect the spindle and
roller together; F is the ordinary spring for giving rotary motion to the roller
when it is desired to wind up the blind attached thereto. One end of this spring is
secured to the spindle B, and the other end is attached to the roller through the
cone D. The roller is closed at its opposite ends by a block G and a plate H, which
are formed with central holes for the spindle to pass through. External of the plate
H is a coiled spring I which surrounds the end of the spindle B, and which I term
the brake spring, its duty being to hold the cones in contact, so that the action of
the spring F when unassisted may be overcome and the pendent blind retained in
any desired position. The spring I is connected at one end to the fixed plate H, its
other end being free. Fitting into one of a series of holes in the spindle B is an
adjustable pin K, which projects through the coils of the spring I for the purpose to
be presently explained. As the blind is drawn down the plate H, by reason of its
attachment to the case, will rotate and wind the spring I coil by coil into the space
between the pin K and the plate H to an extent proportionate to the length of
blind drawn off the roller. This will put a gradually increasing endway pressure
on the cone E proportionately to the increasing force of the coiled spring F due to
the drawing down of the blind and the consequent coiling up of that spring. This
increasing pressure of the brake spring I will cause the cones to bind the more
tightly together, and thus the blind will have no tendency to change its position
until it receives an impetus from below. To provide for this the blind is weighted
at bottom sufficiently to balance the action of the springs, and on the hand being
applied to lift the blind it will receive an upward impulse, which will cease when
that assistance is withrawn. By so adjusting the brake spring that the propelling

page_text: spring will be superior to the retarding action of the friction brake a slow con-
tinuous motion of a blind or sheet may be produced, suitable, for example, for a
moving panorama or for a slow progressive notion in machinery.
A modification of this controlling apparatus is shewn in the partial longitudinal
section, Fig. 2.
In this example the cone E, which is made fast to the spindle B, is a female cone,
into which fits the male cone D made fast to the roller A. The spindle B is threaded
to receive a nut L which closes one end of the hollow roller and is caused to rotate
with that roller by means of a feather and groove connection which permit of the
traverse of the nut upon the threaded end of the spindle. Between the nut L and
cone E the brake spring I is inserted. As therefore the roller is rotated in the
drawing down of the blind, and the recoil force of the spring F is consequently
increased, the nut L will be simultaneously advanced towards the cone E compress-
ing as it advances the brake spring I, and thereby increasing the contact pressure
between the cones.
A mode of applying the friction arrangement to swing doors for the purpose
of checking or controlling either their opening or closing movements is shewn in
the sectional elevation, Fig. 3, where A is a single action swing door which may
be fitted with any desired arrangement of spring for closing it. Applied to the
bottom of the door is a seginent rack B, which gears into a pinion C keyed to a
vertical cone spindle D. This spindle D has its bearings in a spring box E sunk
in the floor, and it receives an axial motion from the swinging of the door. Sur-
rounding the spindle D is the brake spring F, which is attached at its upper end
to the cone G which is free to slide over guides provided for it in the spring
box E; H is a friction cone keyed to the spindle D, and I is a pin fitted to and
adjustable in the spindle D for the purpose of compressing the spring F, and
causing it to hold the cone G in contact with the cone H with a variable pressure
determined by the movements of the swing door. By varying the adjustment of
this apparatus it may be made either to put a gradual check on the opening of the-
door, or to retard its return motion, and thereby to prevent the concussion which
at present takes place with doors swinging in one direction only.
Having now set forth the nature of my Invention of "An Improved Mode of
Regulating the Motive Force of Springs applicable to Roller Blinds, Swing Doors,
and Equivalent Uses," and explained the manner of carrying the same into effect,
I wish it to be understood that under the above in part recited Letters Patent I
claim, in connection with friction brake surfaces, a pressure spring automatically
compressed or wound up and released from compression in the manner and for the
purpose above described.
In witness whereof, I, the said George Slater, have hereunto set my hand
and seal, the Twenty-first day of December, in the year of our Lord One
thousand eight hundred and seventy-six.
GEORGE SLATER. (L.S.)