Improvements in Devices for Automatically Closing Doors.
Year: 1896

page_text: Date of Application, 3rd Sept., 1896-Accepted, 21st Aug., 1897.
COMPLETE SPECIFICATION.
Improvements in Devices for Automatically Closing Doors.
I, JULIUS FURCHTEGOTT FÖRSTER, Mechanician, of Lindenau near Leipzig, in the
Kingdom of Saxony, do hereby declare the nature of this invention and in what.
manner the same is to be performed, to be particularly described and ascertained in and
by the following statement:-
This invention relates to door hinges adapted to close the door automatically, when
it is opened and then left to itself.
In the accompanying drawings Fig. 1 is a front view of a door provided with closing
devices embodying my invention; Fig. 2 is a horizontal section of the same along
line R-R of Fig. 1. Figs. 3 to 7 represent details of construction; and Figs. 8 to
14 represent a modification.
The hinge-plate A fastened to the door is mounted on a hinge pin B provided at
the upper end with a cap or head piece C. The boss of the hinge plate A has at its
lower end a bearing surface a which may be helical, as in Figs. 3 to 7, or in the shape
of an inclined ring, as shown by Figs. 8 to 14.
The pitch of the screw or the angle of inclination of the ring or annular disc may
vary according to the size and weight of the door.
The hinge pin or bolt B carries a friction roller b, which is mounted on a radial
stud and supports the said bearing surface a.
When the door is being opened, the bearing surface a slides over the roller b and
causes the door to rise in accordance with the inclination of the said surface.
Consequently, when the door is subsequently left to itself, it will turn back under the
influence of its own weight. This effect is increased by a helical spring f, coiled
round the upper part of the hinge pin B, between the hinge plate A and the cap C,
the said spring being compressed by the lifting of the door and exerting a downward
pressure on the plate A. The loose cap C has at its lower end a screw-theaded
stud m, which enters a corresponding socket in the upper end of the hinge pin B and
can be screwed down more or less, in order to regulate the pressure of the spring f
and consequently the speed at which the door will close. This regulation may easily
be effected by unskilled persons, and the stud m may be provided with a screw-nut,
in order to secure the screw m, after it has been turned in or out the required
distance.
Figs. 3 and 4 show the position of the door hinge, when the door is closed, and
Figs. 5 to 7 the same when the door is opened.
For retaining the door in the open position, when required, a small bolt R is
applied as shown by Figs. 8 to 14, said bolt being parallel to the hinge pin and
extending downward through the running surface a, so that it may be made to
project through the same and form an abutment for the roller b, which prevents the
spontaneous or accidental turning of the door.
The lower end of the bolt R has such a shape, that the bolt can be pressed back
by a pull applied to the door.
The bolt R is pressed downward by a helical spring g and retained in its highest

page_text: position (until liberated by hand) by means of a flat leaf spring h and a neck i, as
shown by Figs. 8 to 10.
A pair of guide cheeks d, & formed on the hinge-plate A serve to guide the bolt R
parallel with the hinge pin B.
The arrangement represented by Figs. 8 to 14 is suitable for swing doors, because
the inclined annular running surface or race for the friction roller b descends
symmetrically from its highest point, that is to say, equally on the right and on the
left (Figs. 8 and 10); consequently the door will turn back to its mid-position (where
the door is closed), whether it has been opened forward or backward.
The bearing surface a, instead of forming an ordinary cylindrical helix or an
inclined plane, may be shaped in such a manner, that it will retard the motion of the
door shortly before reaching the end of its closing motion, and will thus diminish the
shock and noise produced by the automatic closing of the door.
The shape of the different parts and the means of joining them together may, of
course, vary according to individual requirements and tastes.
Having now particularly described and ascertained the nature of my said
Invention and in what manner the same is to be performed, I declare that what I
claim is:
1. A self-closing door hinge having a movable hinge plate provided with an inclined
bearing surface a, a friction roller b supporting the said hinge plate, and an adjustable
main spring f, the whole being arranged and adapted to operate substantially
as described with reference to Figs. 1 to 7.
2. In a self-closing door hinge, the combination of a movable hinge piece A having
an inclined supporting surface «, with a hinge pin B carrying a friction roller b, an
adjustable main spring f, and a retaining bolt R provided with springs g, h, substantially
as described with reference to Figs. 8 to 14.
Dated this 3rd day of September 1896.
FAIRFAX & WETTER,
433, Strand, London, Agents.