AN IMPROVED DOUBLE ACTING SPRING FLOOR HINGE AND TOP CENTRE FOR SAME
Year: 1880

page_text: LETTERS PATENT to William Cowell and William Withers Chapman, both of
5. Pilgrim Street, in the Borough and County of Newcastle upon Tyne,
Hardwaremen and Plane Manufacturers, for an Invention of "AN IMPROVED
DOUBLE ACTING SPRING FLOOR HINGE AND TOP CENTRE FOR SAME"
COMPLETE SPECIFICATION filed by the said William Cowell and William
Withers Chapman at the Office of the Commissioners of Patents on the 10th
May 1880.
WILLIAM COWELL and WILLIAM WITHERS CHAPMAN, both of 5, Pilgrim Street,
in the Borough and County of Newcastle upon Tyne, Hardwaremen and Plane
Manufacturers. AN IMPROVED DOUBLE ACTING SPRING FLOOR HINGE AND TOP
CENTRE FOR SAME."
"
•
We employ compressed spiral springs in the ordinary metal box of the floor
hinge so arranged as to bear directly on one side of a sliding block the other side
of which bears against the door centre piece, and we construct the door centre piece
of such form as that the pressure of the springs shall tend to keep it in a state of
rest exactly on its centre, and when the door is moved shall give it a constant
tendency to return to its point of rest. We do this by taking the thrust of the spiral
springs before referred to through the intervention of the sliding block on a flat or
concave surface of the door centre piece itself, nearly or exactly in a line with its
centre of motion when the door is at its point of rest, and upon a curved surface
more or less eccentric to the centre of motion when the door is open. For the top
centre we cast the guide pin and centre in one piece instead of in separate parts
as usual, and we provide an oiling arrangement for the lubrication of the top
centre consisting of a recess with a passage into a close cup in which the centre
works.
Having thus described the nature of our Invention, we will proceed more
particularly to describe the manner in which the same is to be performed in and by
the following statement, and having reference to the Drawings hereto attached, that
is to say, Fig. 1 represents a plan of the floor hinge box with its cover removed,
shewing thereby spiral springs S, bolts B, and sliding block D; Fig. 2 is a sectional
elevation of the same on the line a, b, but with its cover on; Fig. 3 is a sectional

page_text: elevation of Fig. 1, on the line c, d, with the box cover in its place; Fig. 4 is a side
view of the bottom centre pin on which the door revolves; and Fig. 5 is a section
through Fig. 4 on the line e, f. Similar lettering of the same parts applies to all
the Figures from 1 to 5.
S, S, are spiral springs free to slide upon the bolts B, B, the purpose of which
bolts is to prevent lateral movement of the spiral springs on compression.
The springs are inserted in the box in a state of compression and bear upon the
end of the floor hinge box c and upon a sliding block D, which is otherwise free to
move within a limited range in the direction of compression and extension of the
springs, but not vertically or laterally, as it is guided on all sides by bearing upon
the box, the bearing surface being of such length as to prevent undue angleing.
The sliding block abuts at the back against the centre piece of the hinge E, and
at its front, as already said, against the springs S:
The centre piece on which the door revolves is shown in elevation and section in
Fig. 4 & 5, the centre of the circle G is the centre of revolution of this centre piece.
The floor hinge box being thus arranged, it will be seen that the partial revolution
in either direction of the central piece E will force the sliding block against the
springs and compress them, and this compression of the springs will represent a
store of reserved power tending continually to relieve itself by the movement of
the sliding block, and the revolution of the central piece towards its point of rest,
that is to say, to the point at which the extension of the springs is greatest. The
peculiar curve of the centre piece causes the pressure of the springs to bear through
the sliding block on one side or other of the centre line of the hinge, even if the
door should be swung somewhat more than 1/, turn from its point of rest, and the
abutment of the sliding block on both sides of the centre piece at its point of rest.
tends to give the hinge stability at this point.
Fig. 6 represents a view of the top hinge, in which A, A, represents the part
attached to the door in which we provide an oiling recess, shewn by dotted lines at
B, B, which is accessible when the door is opened. C, C, represents the part
attached to the lintel; the screw D serves by its rotation to elevate the part
marked E, E, E, which we make in one piece for simplicity and cheapness, and for
the same reason we make the parts marked C, C, C, in one piece, the screw D being
tapped into it, as shewn, and secured in the lintel piece by a pin and collar and
conical head. With the exception of the oil provision and the formation of the
parts A, A, and C, C, each in one piece top centre of door hinge are so made at
present; our improvement in top centre consists in the modification last referred to.
We claim as our Invention the construction of spring hinges for swing doors,
substantially as described.
In witness whereof, we, the said William Cowell and William Withers
Chapman, have hereunto set our hands and seals, this Sixth day of May, in
the year of our Lord 1880.
WILLIAM COWELL.
(L.S.)
Witness to the signing hereof,
JNO. D. WALKER,
WILLIAM WITHERS CHAPMAN. (L.S.)
Clerk with Messrs. Arnott & Swan,
Solrs.,
Newcastle/Tyne.