Improvements in or relating to the Opening and Closing of Doors, and Apparatus therefor.
Year: 1893

page_text: Date of Application, 11th July, 1893-Accepted, 2nd Sept., 1893
COMPLETE SPECIFICATION.
Improvements in or relating to the Opening and Closing of Doors,
and Apparatus therefor.
A communication from OLIVER HEWLETT HICKS, of 116, Lake Street, Chicago,
County of Cock, State of Illinois, United States of America, Manufacturer.
I, ALFRED JULIUS BOULT of 323 High Holborn, in the County of Middlesex,
Chartered Patent Agent, 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:-
The object is to provide electrically operating means that will open and close a
door automatically by a person approaching and passing through a doorway.
In the accompanying drawings-
Figure 1 shows one of a pair of swinging doors in its frame with this invention
applied to one of the doors.
Figure 2 is a diagrammatic view of the circuits containing the electrical door-
operating mechanism.
Figure 3 is a broken sectional view taken transversely of a door, to show the mats
at opposite sides of the approach.
Figure 4 is a broken plan view of the preferred species of mat.
Figure 5 is a perspective view showing the upper end of a door and certain
details of the operating mechanism.
Figure 6 is a longitudinal sectional view of the electro-magnetic friction clutch,
the section being taken at the line 6 on Figure 8; and Figure 7 is an end view of
the same.
Figure 8 is a section taken at the line 8 on Figure 6.
Figure 9 is a diagrammatic view, in side elevation, of the electro-magnetic portion
of the clutch.
A and A are double doors, with the operating mechanism shown, however, as
applied only to the first-named, since its application to the other may involve
duplication of the mechanism. The doors are represented as of the variety
supported at one edge on hinges to swing in a horizontal plane, though the
improvement applies equally to other varieties of door, such as a sliding door,
to operate which the mechanism hereinafter described may readily be adapted.
B is a circuit making and breaking electric mat, which may be of well-known
construction, and the position of which is at the approach to the threshold, one
being provided at each side of the door, or a continuous mat may be provided to
extend at opposite sides of the door. By stepping on either mat its normally
separated contacts t and t¹ are caused to engage each other and thereby effect
closure of a circuit on the wires w, w', with the result hereinafter described.
As shown of the door A, it is adapted, in accordance with the preferred arrange-
ment, to be closed against a spring C (Figures 1 and 4) fastened at one end to
the door and at its opposite end to some stationary object, whereby when the door
is released from the means which hold it in its closed condition, the resilient force
of the spring will open it; and the operation is hereinafter so described, though the
mechanism may readily be adapted, and it were within the purpose of the invention
so to adapt it, to open the door against a closing spring, or to both open and cle
the door positively without the employment of any spring for either purpose.
The motor-mechanism, which is set in operation by the closure of the circuit
at the mat B, is best located above the door, as represented, where it may be
suitably incased.
D (Figure 2) is an electro-magnet having its pivotal armature D¹ linked at its

page_text: free end with one end of a pivotal circuit-closing finger D2 tending normally, by
the effect of a spring s, to engage contacts t² 1³.
E is an electric motor of any suitable construction; and from the rotary arma-
ture of the motor depends an extension of its shaft terminating in a worm g¹
meshing with a worm-wheel p on the end of a rotary shaft p' carrying an electro-
magnetic clutch F (Figures 6, 7 and 8). The clutch is necessarily yieldingly
frictional in the co-operation of its clutch-members. It comprises, as a preferred
construction, but not the only construction suitable for my purpose, provided it be
yieldingly frictional, as stated, a series of electro-magnets n secured on the shaft pl
to rotate with it, and the cores n' of which extend at their pole-ends through and
flush with a non-magnetic (as brass) head 2, which may be recessed, as shown at v
in Figure 6; and an armature m in the form of a conical or tapering spool, (which
may be recessed as at 1,) is loosely supported on the shaft pl to rotate with it only
when attracted by the magnets, the spool having a circumferential spiral groove m².
In one end of the groove is fastened an end of a cord, m², or other flexible medium,
the other end being fastened to a clip m³ (Figure 1) extending from the upper end
of the door A near which it passes about a stationary guide-pulley m.
rear end of the magnets n are two conducting rings n to which, respectively, are
applied the brushes n° and 16.
At the
This forms a yielding friction-clutch, not wholly positive in its operation, the
friction being between the spool and the face of the non-magnetic plate and
magnet-poles.
Other details are hereinafter set forth in the explanation of the electric circuits
illustrated diagrammatically in Figure 2, and of which the following is a
description:
:
W and W' may be the line-wires of an incandescent-lamp circuit, lamps L in
a branch of which then serve as resistances against excessive current entering the
mat-circuit, though by way of further precaution fusible cut-outs L' are inserted
into that circuit.
As will be understood, this invention is not limited to use with any particular
kind of electric generator, the lamp-circuit being selected for illustration because it
is liable to be found in buildings employing this door-operating apparatus and may
then be conveniently utilized.
From the line W leads the conductor w¹ through a binding-post device W2, the
adjacent lamps L and fuses L' and electro-magnet D, to the mat-contacts t¹; and
from line Wleads the conductor w through a binding-post device W3 and the
A branch-circuit is
adjacent lamps L and fuses L' to the mat-contacts t.
formed with the wire w³ leading from the device W2 to the finger D². Another
branch-circuit is formed with the wire w leading from contact t² of circuit-closer D'
through the electro-magnet of clutch F to binding-post W³. Still another branch-
circuit is that formed with the wire w leading from contact t³ through motor E to
a circuit-closer D³, whence wire w' leads to binding-post D³.
The circuit-closer D³ is shown as a bell-crank k and contact-plate k', the finger
being controlled by a spring s¹ to tend to make contact with plate k¹, and having
fastened to one of its arms a cord i connecting it with a bell-crank pivoted above
the door and connected by a cord i with another bell-crank g pivotally supported
above the door, on which is an upward projecting finger fin position to engage the
bell-crank g in the closure of the door.
With door A closed, as represented, the parts occupy the relative positions
illustrated; and the holding of the door closed, by the means for the purpose
hereinafter described, or by any other suitable means, causes the bearing of finger
against bell-crank g meantime to maintain bell-crank k in the position shown in
Figure 2, thus out of contact with plate k'. The contacts t and t¹, in the closed
condition of the door, being separated, it will be clear that all the circuits but one
(the clutch-circuit) are open, and the motor-mechanism is at rest, with cord m²
wound upon the spool-armature m to hold the door shut against spring C, the cord
being held by the clutch, which, during the closed condition of the door, is in the

page_text: closed circuit formed with the wires w¹, w³, finger D², contact t² and wires w¹, w,
whereby the magnet-portion of the clutch is energized to hold the pulley m.
The door is opened automatically by stepping on the mat B to bring together the
contacts t, t. Thereby, primarily, closure of the circuit is produced over wire w
and wire w' through magnet D, and consequent attraction of armature D', with the
result that finger D2 is separated from contacts t², t³, thus breaking the circuit con-
taining the friction-clutch and releasing the spool-armature m, whereby it will yield
freely to the recoil of spring C, which opens the door and thereby turns spool m to
cause the cord m² to unwind from it. As the door opens, separation ensues of
finger from bell-crank g, whereby the spring s¹ is freed to recoil and bring the
finger against contact k¹ and thus prepare the motor-circuit for closure
when finger D shall again engage contact t³.
So long as the contact-producing pressure is maintained on the mat, as it would
be while a person were passing through the doorway-the motor and clutch
containing circuits will remain broken at D2. When the pressure ceases, as by the
person passing from the door, mat-contacts t, t¹, immediately open the circuit w, w',
thus deenergizing magnet D and allowing springs to effect engagement of finger D³
with the contacts t², t³. This causes closure of the motor and clutch circuits,
whereupon magnetization of the clutch ensues to attract and hold its spool-armature,
and also rotation of motor E, which produces, through the worm-gear, rotation of
clutch-shaft p¹ and consequent winding on spool m of the cord m² with resultant
closure of the door. As the door closes, finger f bears against bell-crank g and
disconnects finger k from contact k' cutting out and stopping the motor and rotation
of the clutch, which, however, still remains in the closed circuit, 101, 102, 12, 12, 10, 20,
and thereupon continues its hold on the door against spring C.
A matter of very considerable importance for the practicability of the apparatus
is that the operating mechanism shall be sensitively responsive to the primary, or
mat, circuit-closing means to a degree that will cause automatic reopening of the
door from any point in closing that it may have reached, so that a person stepping
on the mat to pass through the doorway during swinging of the door toward its
position of closure, shall not be required to await the full closing of the door to be
enabled to pass.
This function is performed to a nicety by the described
mechanism; since whatever point the door may reach in closing, contact at t, t',
will immediately effect stoppage of the motor and release of spool m to permit the
opening-spring C to act.
The nature of this invention requires that the description of the particular
mechanism selected for illustrating it shall be in the foregoing accurate detail. But
it is not intended to limit the invention to mere details of construction, as it is
generically novel to provide a door with any electrical motor-mechanism containing
an electric friction-clutch and set in motion to operate the door by stepping on an
electric mat, or analogous platform. From the foregoing disclosure of the invention
various other means for accomplishing the same purpose with the specified motor,
friction-clutch and mat or platform features, are likely readily to suggest them-
selves to others; and all such are intended to be included as within this invention.
One such change would be to provide any suitable construction of resilient
platform in lieu of an electric-mat form of platform, and causing it to operate,
mechanically, by stepping on and off it, to affect the primary circuit w, w in the
desired manner.
Having now particularly described and ascertained the nature of the said inven-
tion, as communicated to me by my foreign correspondent, and in what manner
the same is to be performed, I declare that what I claim is :-
1. In combination with a door, an electric motor, an electric friction-clutch
operatively connected with the motor and door, the clutch and motor being included
in electric circuits, and a platform, stepping on and off which produces operation of
the door, substantially as described.
2. In combination with a door, an electric motor, an electric friction-clutch

page_text: connected with the motor to be rotated thereby to operate the door in one direction
and having a spool-armature supported on the clutch-shaft, a flexible connection
between the spool-armature and door, a platform, and means for operating the door
in the opposite direction to the said clutch-operation thereof, the motor and clutch
being included in electric circuits, whereby stepping on and off the platform
produces operation of the door, substantially as described.
3. In combination with a door, an electric motor E, an electric friction-clutch F
connected with the motor to be rotated thereby to operate the door in one direction
and having a tapering spirally-grooved spool-armature m supported to slide on the
clutch-shaft, a flexible connection m² between the spool-armature and door, an
electric mat B, and a spring C for operating the door in the opposite direction to
the clutch-operation thereof, the motor, clutch and mat being included in electric
circuits to be operated substantially as described..
4. In combination with a door, an electric mat B controlling a normally open
electric circuit closed by pressure on the mat, an electro-magnet D in said circuit,
a motor E in an electric circuit normally opened by the door when closed and
geared to an electric friction-clutch F in a normally closed electric circuit opened
by closure of the mat-circuit, the clutch having a sliding spool-armature connected
by a flexible medium m² with the door to close it by operation of the motor, a
contact-finger D2 normally closing the motor and clutch-circuits and controlled
to open the same by the armature of magnet D, and a spring C for opening the
door, the whole being constructed and arranged to operate substantially as
described.
5. In combination with a door, an electric mat B controlling a normally open
electric circuit closed by pressure on the mat, an electro-magnet D in said circuit, a
motor E in an electric circuit containing a circuit-closer D³ having a contact-finger k
controlled by a spring s¹ and connected with a lever g above the door, a projection f
on the door bearing against the lever g and maintaining open the motor-circuit when
the door is closed, an electric-clutch geared to the motor and in a normally closed
electric circuit, the clutch having a sliding spool armature m connected with the
door by a cord m², a contact-finger D2 normally connecting the motor and clutch
circuits, and a spring C for opening the door, the whole being constructed and
arranged to operate substantially as described.
Dated this 11th day of July 1893.
W. P. THOMPSON & BOULT,
Agents for the Applicant.