A NEW OR IMPROVED DOOR SPRING
Year: 1879

page_text: LETTERS PATENT to Edward Bull, of Halifax, in the County of York, Civil
Engineer and Architect, for the Invention of "A NEW OR IMPROVED DOOR
SPRING
"
Sealed the 9th April 1880, and dated the 10th October 1879.
PROVISIONAL SPECIFICATION left by the said Edward Bull at the Office of
the Commissioners of Patents on the 10th October 1879.
EDWARD BULL, of Halifax, in the County of York, Civil Engineer and Architect.
"A NEW OR IMPROVED DOOR SPRING."
This Invention consists in a new construction and arrangement of door spring
for closing doors automatically.
The improvements consist in inserting a box within the edge of the door, and
also another box within the door jamb. A suitable length of india-rubber or other
elastic material is attached at each end, one end in each box, and rests or bears
upon friction pullies, so that when the door is opened the india rubber spring will
immediately close it. Instead of the elastic spring metal springs may be
employed.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Edward Bull in the Great Scal Patent Office on the 9th April
1880.
EDWARD BULL, of Halifax, in the County of York, Civil Engineer and Architect.
"A NEW OR IMPROVED DOOR SPRING."
This Invention consists in a new construction and arrangement of door springs
for closing doors automatically. The improvements consist in inserting a box within
the edge of the door, and also another box within the door jamb. A suitable length
of india-rubber or other elastic material is attached at each end, ono end in each
box, and rests or bears upon friction pullies, so that when the door is opened the
india-rubber spring will immediately close it. Instead of the clastic spring metal
springs and chains may be employed.
In order that this Invention may be better understood I have annexed a Sheet
of Drawings illustrative thereof, Fig. 1 being a cross section of the apparatus,
wherein A is the door jamb and B the door, swinging on the hinge C in the ordinary
manner. Into the edge of the door and door jamb I let-in a box or casing D, having
friction rollers E, upon which bears the elastic spring F secured at each end to the
lugs f. It will be seen that when the door B is opened in the direction of the arrow
that the clastic spring will be stretched, so that when the opening pressure is taken
off the door the spring will bring the door to or close it. By these means the
springs, bars, and levers which are now placed outside the door are dispensed with.
Fig. 2 illustrates front view of the box or casing D, and Fig. 3 end view; and Fig. 4
is back view of the boxes when put together, A being the jamb and B the door.
Instead of using the india-rubber spring F, I may use a spiral metal spring H in
conjunction with chain J (see Figs. 5 and 6, which are cross sections); D is the box
or casing, as in the previous case, K. being the barrel around which the chain is
wound, and L the spindle or shaft upon which the spring H is placed. Fig. 7 is
elevation of box placed in the door jainb; and Fig. 8, elevation of box placed in the
edge of the door; and Fig. 9 is view shewing position of parts when the door is
open; Figa 10 and 11, which are plan and cross section of another arrangement of
chain and metal spring, H being the chain bearing upon friction rollers E, and M is
the spiral spring.
Having thus fully described the nature of my said Invention, and shewn by
Drawings in what manuer the same is to be or may be performed or carried into
practical effect, I would have it understood that I do not confine myself to the
precise details of construction as herein shewn and described, but,-
Firstly. I claim the parts D, E, F, when used in combination and placed within
the edge of the door jamb and door, substantially as described and illustrated.
Secondly. I claim the parts D, H, and J, when used in combination and placed in
the position substantially as described and illustrated.
Thirdly. 1 claim the parts E, H, and M, when used in combination and placed in
the position substantially as described and illustrated.
In witness whereof, I, the said Edward Bull, have hereunto set my hand and
seal, this Third day of April, in the year of our Lord One thousand eight
hundred and eighty
EDWARD BULL. (L.S.)
Witness,
A. B. CROSSLEY.