An Improved Method of Opening and Closing the Entrances to Lifts, Hoists, and the like.
Year: 1892

page_text: Date of Application, 39th Jan., 1892
Complete Specification Left; 31st Oct., 1892-Accepted, 17th Dec., 1892
PROVISIONAL SPECIFICATION.
An Improved Method of Opening and Closing the Entrances to Lifts,
Hoists, and the like.
I, ROBERT MIDDLETON, of Sheepscar Foundry, Leeds, in the County of York,
Engineer, do hereby declare the nature of this invention to be as follows:
This invention has reference to a method or system whereby (1) the closed doors
in the various entrances are automatically raised and lowered, by a passing cage,
both on its up and down journeys, and (2) whereby any of the said doors may be
kept closed when desired. It further refers to an arrangement by which doors may
be drawn up and made to occupy a minimum space.
The object of the invention is to produce (1) a compact automatic safety
appliance, whose simplicity and reliability will lead to its general adoption, and (2)
to so arrange the mechanism that it shall allow any door on any landing to be kept
closed; the ultimate object being safety to the users of the lift. The compactness
of the mechanism enables it to be inserted in the space usually left at the sides of
the well of the lift, the whole arrangement being designed with this in view.
When my apparatus has to be adapted to ordinary doors, the cords for drawing
them up, and letting them down, must be led to and fro over suitable pullies. My
appliance has to be fixed in connection with each landing; and each door, or the
appliance itself, must be counterweighted, in any suitable manner, so as to auto-
matically close the entrance when, and
as, the cage
travels away.
My mechanism consists of an arrangement of two chain wheels, fixed in a line,
one above the other, so that their distance apart causes the encircling chain to
present straight lengths in passing from one wheel to the other, proportioned to the
height of the doors to be lifted. On the straight pieces of the chain projecting
fingers are fitted, and to these are attached the aforesaid rope or ropes from the
doors, so that, when the fingers travel with the chain from end to end of the straight
paths, the particular door acted upon is drawn up and its entrance opened. The
rope from a door need only be attached to one finger, as the two fingers are attached
to one another, by being mounted on the same chain. The fingers may be guided
in their straight paths, as the individual links of the chain to which they are attached
do not pass round the chain wheels.
The cage of the lift has two catches mounted on it; one, at its foot, for engaging
with the top finger on the chain, on a downward journey; and, the other, at its head,
for engaging with the lower finger, on the opposite straight side of the chain, on an
upward journey; the two catches being arranged at suitable distances apart (in
plan) to suit these two fingers.
It follows from what has been described, that, when the lower catch of a
descending cage engages with a finger standing at the top of its path (drawn into
that position by the released door), the door will again be drawn up as the cage
continues to descend.
In order however to govern the distance through which the finger is thrust down
(and the door opened) a releasing-piece, with a suitably inclined face, is so fixed to
my appliance that the catch of the cage is thrust, sideways, off the end of the finger,
and the door again liberated. Of course this liberation is arranged to take place
after the cage has been re-started, by fixing the position of the releasing-piece low
enough down to suit. When the finger is released, and the cage moves away, the
weight of the door, or its equivalent, draws the finger back to its top position, and
consequently, draws the oppositely mounted finger down. This same catch on the
foot of the cage strikes, on its upward journey, on a lower incline on this releasing-
piece, and thus gets past it; and a similarly slanted lower side to the finger enables

page_text: it to pass this also. The catch itself also has the abutting side bevelled off. The
cage on its upward journey works exactly in the same way;-that is to say, the top
catch strikes the bottom finger and again the door is opened, its release being
governed by another releasing-piece, which comes into play as the cage re-starts and
moves upwards.
By a special connection of these two catches, on the cage, they may be put in or
out of gear so as not to strike the fingers of my appliance, on any landing at which
it is desired not to stop. Such a gear I arrange by preference to be worked by the
attendant's foot, thus leaving his hands free for other matters. In ordinary working
the cage catches may be kept in gear by springs.
When a cage, working either up or down, has raised a counterweighted door, the
said door would be free to fall (in guillotine fashion) directly the cage moved
forward, which would be very undesirable. To meet this the two catches are so
arranged, on the top and bottom of the cage, that they play into one another's field
of action. For instance, when a descending cage has raised a door, and when, on
re-starting, it is liberating the finger in action, the other catch is engaging with the
other finger, and by this means the door cannot fall at a greater speed than that
at which the cage moves away;
The finger which descends when the door is raised may be enlarged into a counter-
weight when desirable.
The mode of connecting and working the doors from my mechanism may be
varied in many ways without departing from the essential features of the invention.
My special arrangement of door which I propose to use, by preference, in con-
nection with this appliance, I make after the manner of a Venetian blind, so that the
whole may be drawn up into a minimum space at the head of the doorway. Only
certain of the laths need be made of strong material when weight is an object. A
curtain with safety bars behind it, being an alternative form.
Dated this 29th day of January 1892.
WM. SNOWDON,
9, Old Bank Chambers, Leeds, Yorks., Agent for the Applicant.
COMPLETE SPECIFICATION.
An Improved Method of Opening and Closing the Entrances to Lifts,
Hoists, and the like.
I, ROBERT MIDDLETON, of Sheepscar Foundry, Leeds, in the County of York,
Engineer, 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 a method or system whereby (1) the closed doors
in the various entrances are automatically raised and lowered, by a passing cage,
both on its up and down journeys, and (2) whereby any of the said doors may be
kept closed when desired. It further refers to an arrangement by which doors
may be drawn up and made to occupy a minimum space.
The object of the invention is to produce (1) a compact automatic safety
appliance for hoist entrances, etc., whose simplicity and reliability will lead to its
general adoption, and (2). to so arrange the mechanism that it shall allow any door
in any landing to be kept closed; the ultimate object being safety to the users of
the lift. The compactness of the mechanism enables it to be inserted in the space
usually left at the sides of the "well" of the lift, the whole arrangement being
designed with this in view.
In order to fully explain my system I have annexed a drawing on which
Fig. 1 is a portion of a plan, and Figs. 2 & 3 are corresponding front and side
elevations of parts of the mechanism. Fig. 4 corresponds with Fig. 2, with the
tappets or fingers in different positions; and Fig. 5 shows, in elevation, a mode of

page_text: throwing the main catches out of gear. The parts drawn are to be taken as
explanatory only, as a variety of details may be had without departing from the
essential features of the invention. The same letters refer to the same parts in all
the figures.
When my apparatus has to be adapted to ordinary doors, the cords for drawing
them up, and letting them down, must be led to and fro over suitable pullies
arranged at either side of the "well." The part of my appliance shown in
Fig. 2 has to be permanently fixed in connection with each landing; and each door,
or the appliance itself, must be counter-weighted, in any suitable manner, so as to
automatically close the entrance when, and as, the cage travels away.
Referring to Fig. 1 etc., A is the cage, which carries the left hand catch B' on
its roof, and the right hand catch, B, beneath its floor. C is one of the cage
guides introduced to show the space, between the cage and the side of the "well,"
in which any apparatus is fixed. To avoid confusion no portions of the cage, except
its catches B1 and B2, are shown in Figs. 2 and 4; whilst in Fig. 3 the cage is shown
stopping at a landing corresponding to that in Fig. 2.
My fixed mechanism consists of an arrangement of two chain (or other like)
wheels, D' and D', fixed in a vertical line, one above the other, so that their
distance apart causes the encircling chain or rope E to present straight lengths, in
passing from one wheel to the other, proportioned to the height of the doors to be
lifted. On the straight lengths of the chain projecting fingers F1 and F2 are
fitted, and, at the foot, the chain or rope is led away over the pulley D³ to the
door, so that, when the fingers travel with the chain from end to end of their
straight paths, the particular door acted upon is drawn up and its entrance opened.
The fingers are guided in their straight paths by being mounted on square bars G'
and G, as the portions of the chain to which they are attached do not pass round
the chain wheels.
The cage of the lift has, as before mentioned, two catches mounted on it; one, B²,
at its foot, for engaging with the top finger F2 on the chain, on a downward
journey; and, the other, B', at its head, for engaging with the lower finger F¹ on
the opposite straight side of the chain, on an upward journey; the two catches
being arranged at suitable distances apart (see plan) to suit these two fingers.
It follows from what has been described, that, when the lower catch B* of a
descending cage engages with a finger F standing at the top of its path (drawn
into that position by the weight of the released door), the door will again be drawn
up as the cage continues to descend. This will be understood by referring to
Fig. 2, where H is a weight at the foot of a door arranged like a Venetian blind
and drawn up by the rope passing over the pulley at its head. A door may be
arranged to open and close in any direction.
see.
In order however to govern the distance through which the finger is thrust down
(and the door opened) a releasing-piece J, with a suitably inclined face, is so fixed
(preferably for the sake of adjustment by being clamped on the bars G' and G²)
that the catch B' of the cage is thrust, sideways, off the end of the finger, and the
door again liberated. This action is shown in progress at the foot of Fig. 4, which
Of course this liberation is arranged to take place after the cage has been
re-started, by fixing the position of the releasing-piece low enough down to suit
the landing. When the finger is released, and the cage moves away, the weight of
the door, or its equivalent, draws the finger F back to its top position, and con-
sequently, draws the oppositely mounted finger F down. This same catch B² on
the foot of the cage, strikes, on an upward journey of the cage, on a lower
incline, on this releasing-piece, and thus gets past it; and a similarly slanted
lower side to the finger will enable it the better to pass it also, supposing the
inclines of J' have not caused them to clear one another. The catch itself may
also have the abutting side bevelled off.
The cage on its upward journey works exactly in the same way; that is to say,
the top catch B' strikes the bottom finger F' (see the foot of Fig. 2) and
again the door is opened, its release being governed by another fixed releasing-

page_text: piece J, which comes into play as the cage re-starts and moves upwards; see top
of Fig. 4.
By a special connection of the two catches, B1 and B2, they may be put in or out
of gear by inclines and arranged on a rod K, as shown in Fig. 5, so as not to
strike the fingers of my appliance, on any landing, at which it is desired not to
stop. Such a gear I arrange, by preference, to be worked by the attendant's foot
being placed on the ledge L, thus leaving his hands free for other matters.
spring at M lifts the rod out of gear when released. In ordinary working the
cage catches may be kept in gear by springs shown at and b, Fig. 1.
A
When a cage, working either up or down, has raised a counter-weighted door,
the said door would be free to fall (in guillotine fashion) directly the cage moved
forward, which would be very undesirable. To meet this the two catches are so
arranged, on the top and bottom of the cage, that they play into one another's field
of action. For instance, when a descending cage has raised a door, and when, on
re-starting, it is liberating the finger in action, see B2 at the foot of Fig. 4, the
other catch B', which is descending also, engages with the other finger F', and by
this means the door cannot fall at a greater speed than that at which the cage
moves away when once B' gets under F
The finger F which descends when the door is raised may be enlarged into a
counter-weight when desirable; or any other such arrangement may be made to
keep the chain tight, etc.
The mode of connecting and working the doors from my mechanism may be
varied in many ways.
The special arrangement of door which I propose to use, by preference, in
connection with this appliance, I make after the manner of a Venetian blind, as
shown in Figure 2, so that the whole may be drawn into a minimum space at
the head of the doorway. Only certain of the laths need be made of strong
material when weight is an object. A curtain protected with safety bars behind
it, or a revolving shutter, being alternative forms. The diameter of the revolving
roller d drawing up the door allows any desired height to be easily arranged what-
ever length of movement be given to the fingers.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
(1). The system of automatically opening and closing entrances to lifts and the
like by causing catches on the head and foot of the cage to act on fingers attached
to chains or ropes stretched over pulleys and connected with the doors; the said
catches being further acted upon by fixed inclines as the cage approaches and leaves
the various landings, substantially as described and shown.
(2). The system of automatically opening and closing entrances, as referred to
in the first claim, which allows itself to be supplemented by throwing-out
mechanism, such as shown in Fig. 5, whereby any desired doors may be passed
without being opened, substantially as described and shown.
(3). The general arrangement of that part of my appliance which bolts to the
side of the well, as shown in Fig. 3, consisting of the end fixtures carrying the
wheels D & D', and on which are mounted the guide bars G & G carrying
the fingers F & F, on which bars are mounted the adjustable releasing
inclines J&J substantially as described and shown, with the object and for the
purpose set forth.
(4). The combination of a door, or protected curtain, on the Venetian-blind
system, or other equivalent revolving shutter, with the automatic raising and
lowering mechanism herein described and shown, with the object and for the
purpose set forth.
(5). The arrangement of right and left hand external catches B' & B' in coin-
bination with a throwing-out gear, such as shown in Fig. 5, whereby any door (the
fiugers F and F being untouched) may be left undisturbed, in whatever direction

page_text: the cage may be travelling, substantially as described and shown, with the object
and for the purpose set forth.
(6). The method of arranging the catches B' & B' and the releasing pieces J' & J
to so overlap one another's field of action that a descending door cannot fall at a
greater speed than that due to a departing cage, substantially as described and
shown, with the object and for the purpose set forth.
Dated this 29th day of October 1892.
WM. SNOWDON,
9, Old Bank Chambers, Leeds, Yorks., Agent for the Applicant.