Improvements in and relating to the Automatic Closing of Doors.
Year: 1894

page_text: Date of Application, 27th Jan., 1894
Complete Specification Left, 27th Oct., 1894-Accepted, 1st Dec., 1894
PROVISIONAL SPECIFICATION.
Improvements in and relating to the Automatic Closing of Doors.
A communication from abroad by ROBERT ORR, of Brooklyn, New York, United
States of America, Patternmaker.
I, RICHARD MACGREGOR, of Hawthorn Buildings, Laigh Park, Paisley,
Renfrewshire, Timber Measurer, do hereby declare the nature of my invention to
be as follows:-
This invention has reference to and comprises a new or improved method, and
arrangement and combination of appliances for automatically closing swing and like
doors after they have been opened, such as the doors of buildings, public places
railway carriages and the like.
The improvements essentially consists in opening the door against the action of a
volute or equivalent spring, which operates a piston working within a cylinder;
and the recoil of which spring assisted by an inrush of air behind the piston will
automatically bring back the door to its closed position.
In carrying these improvements into practice under one arrangement I fit a
piston to work on a rod within a cylinder or casing which would be screwed or
secured by a back plate or bracket to the inner side of the door, preferably near its
end;
upper and a hole or opening would be formed in the bottom or end of cylinder,
regulated by a screw, for admitting pressure air behind the piston. Over this
cylinder would be fitted another cylinder or casing to rotate freely round the piston
rod, and a volute or equivalent spring would be fitted within this cylindrical
chamber having its one end bearing on a projection within cylinder and its other
end bearing in a slot or recess formed in piston rod. An overhung fixed bracket
or cover would be placed over the rotating cylinder and be screwed or secured to
the back plate of lower fixed cylinder; and this cover would be formed with cam
or inclined grooves in which would work a screw pin or arm secured to the piston
rod, and preferably have an antifriction roller on it, and the action of which would
reciprocate the piston as hereinafter described. A radial arm or crank would be
mounted on the upper end of the piston rod, and have its outer end connected to
the one end of an adjustable rod or arm secured to the fixed frame of the door
preferably above the lintel, and capable of adjustment by right and left hand screws
working in socket bearings at its centre part.
In opening the door the piston rod is turned, and also receives a downward
reciprocatory motion which presses piston to lower end of cylinder and causes a
partial vacuum therein; while on the door being let free, the recoil action of the
spring will turn the piston rod which will also be raised or reciprocated upwards by
the inclined groove in the top cover, and the inrush of air through aperture in lower
cylinder will press the piston up to its uppermost travel, and the door will thus be
quickly and automatically closed.
The piston would preferably be so mounted on its rod that it will be held by
stops on each side of cylinder at its top travel position, while the rod will be free
to rotate and travel as described; and a relief air valve would be fitted on top of
piston.

page_text: A ratchet or toothed wheel would be formed on or fitted round the loose rotating
cylinder, and be operated by a wheel, worm, or pawl and hand lever mounted on
the top of fixed lower cylinder for adjusting same when desired by hand.
Dated the 26th January 180.1
W. R. M. THOMSON & Co.,
96, Buchanan Street, Glasgow, Agents.
COMPLETE SPECIFICATION.
Improvements in and relating to the Automatic Closing of Doors.
I, RICHARD MACGREGOR of Hawthorn Buildings, Laigh Park, Paisley,
Renfrewshire, Timber Measurer, 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 has reference to and comprises a new or improved method and
arrangement and combination of appliances for automatically closing and preventing
the slamming of swing and like doors, after they have been opened, such as the
doors of buildings public places, railway carriages and the like.
I will describe my invention by reference to the accompanying drawings on
which
Fig. 1 shews a door partly opened with my said invention applied ;
Fig. 2 is a side elevation of the main portion of my invention on an enlarged
scale; Fig. 3 is a plan of the same; Fig. 4 is a sectional elevation of the same,
shewing the parts as when the door is closed, and Fig. 5 is a sectional elevation
of the same shewing the parts as when the door is opened.
The same letters of reference indicate the same parts in all the figures.
In carrying out this invention I provide a piston A fixed on a piston rod a¹
within the cylinder or casing B which by the back plate is fixed to the inner side
of the door C preferably near the top of the same; and in the bottom end of the
cylinder B there is or may be a hole d closed by a spring valve e opening down-
wardly; or instead of this hole d in the cylinder there may be a hole in the piston
closed by the valve g opening upwardly so as to allow of the escape of air from the
cylinder below the piston when the door is being opened and the piston is descending
as hereinafter described, aud prevent or check the flow of air to the cylinder below
the piston when the latter is rising. Over the cylinder B there is fitted another
cylinder or chamber H arranged to be capable of freely revolving round the piston
rod a (but held stationary as hereinafter described), and a volute or equivalent
spring I is fitted within this cylindrical chamber H having its outer end h¹ fixed by
the screw projecting in the cylinder and its inner end 2 bearing in a slot or
recess a² formed in the piston rod. An overhanging fixed bracket or cover J is placed
over the revolving cylinder H and secured to the back plate of the lower fixed
cylinder B; and this cover J is formed with a cam or inclined groovej in which works
a pink secured to the piston rod a' (and if desired provided with a friction roller
on it to work in the groove j') so that as the piston rod and piston are turned as
hereinafter described the action of the incline j¹ on the arm k imparts a reciprocal
motion to the piston rod and piston. A radial arm or crank L is mounted on the
upper end of the piston rod a' and at its outer end i¹ is connected to one end m¹ of an
adjustable rod M which at the other end m² is jointed to a bracket N fixed to the
fixed frame of the door C preferably above the lintel and capable of adjustment by
an ordinary right and left hand screwed connector m³.
The act of opening the door C through a small angle causes the piston rod a¹ to
turn and coil the spring I more round the piston rod a' which by the incline j¹
acting on the arm k also receives a downward movement pressing the piston to the
lower end of the cylinder (as shewn in Fig. 5) and forcing the air out of the same
through the hole d or through the hole f. After the door has been opened through

page_text: a small angle as aforesaid the reciprocative motion of the piston rod and piston
ceases as the pin k on the piston rod a¹ has then moved off the inclined part of
the groove and is moving along the straight portion of the same. On the door
being let free the recoil action of the spring I turns the piston-rod and piston and
closes the door, but when the door is almost closed and the pin k commences to
ride up the inclinej¹ the piston rod a¹ and the piston A will by the incline be
reciprocated upwardly causing a partial vacuum in the cylinder B below the piston A
so that the pressure of the air on the top of the piston A will then retard the
movement of the piston and door and ensure the door closing slowly at the finish
and effectually prevent slamming.
In order to readily adjust the tension of the spring I there is a worm wheel o
formed with the moving cylinder H and gearing with this wheel o there is a
worm P mounted on a spindle p carried by bearings g' formed with the fixed
cylinder B so that by a key or other means the spindle pand worm P and wheel o
and cylinder H can be turned to adjust the tension of the spring I and the worm
and worm wheel will keep the spring at any desired tension without the use of a
ratchet and ratchet wheel or other contrivance. Although I prefer to employ the
worm and worm wheel for adjusting the tension of the spring I still I do not confine
myself to these means as other well known means such as a ratchet and ratchet
wheel may as in other door springs be employed for the same purpose.
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. In an automatic door closing appliance the combination of the cylinder and the
piston therein provided with a piston rod having a lever arm for turning the same,
the spring coiled round and connected to the piston rod so as to be coiled thereby
and turn the same to close the door, the said piston rod having a projection which
is acted upon by stationary inclines so that when the piston is turned to coil the
spring round the piston rod the piston will be moved along the cylinder and expel
the air therefrom through a suitable valve and on the recoil of the spring turning
the piston rod in the opposite direction the piston will also by the inclines be caused
to travel in the opposite direction and form a partial vacuum in the cylinder on one
side of the piston so that the outer air pressing on the other side of the piston will
check the recoil of the spring as hereinbefore set forth.
2. The combination of the cylinder, the piston, and piston rod, the spring, the
movable cylinder surrounding the spring means for turning and fixing the movable
cylinder, the projecting pin on the piston rod and the stationary inclines for acting
on the same, the lever arm fixed on the piston rod for turning the same, and the air
valve e or g for the escape of air from the cylinder, all arranged substantially as
herein before described and illustrated by the accompanying drawings.
3. In an automatic door closing appliance and in combination with the coiled
spring and spring containing cylinder the worm and worm wheel for adjusting the
tension of the spring arranged substantially as hereinbefore set forth and shewn.
4. The combination with a door and door frame of the automatic door closing
appliance arranged and operating as herein before described and illustrated by the
accompanying drawings.
Dated this 26th day of October 1894.
CHARLES BOSWORTH KETLEY,
Agent for the Applicant.