Improvements in Elevators or Lifts.
Year: 1888

page_text: COMPLETE SPECIFICATION.
Improvements in Elevators or Lifts.
A communication from abroad by CHARLES ROLLIN OTIS, of Yonkers, in the County
of Westchester and State of New York, United States of America, Manufacturer.
I, PHILIP MIDDLETON JUSTICE of 55 and 56 Chancery Lane, in the County of
Middlesex, Fellow of the Institute of Patent Agents, 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 for its object to facilitate the working of elevating apparatus, and
to reduce the danger of accidents liable to result from excessive speed of the cage and
otherwise to improve the construction of such apparatus and details thereof.
The first part of this invention relates to that class of elevators in which the move-
ment of a valve through the medium of devices controlled from the cage or platform,
is the means of stopping and starting the cage, and especially of that class in which
electro-motors are employed in connection with the valve actuating devices.
To clearly illustrate the nature of the invention reference is made to the accompany-
ing drawings in which :-
Fig. 1 is an elevation of a hydraulic elevator embodying the present improvements.
Fig. 2 is an enlarged vertical section of the elevating engine.
Fig. 3 is a sectional elevation illustrating the invention in connection with an
elevator engine in which the valve is shifted directly by hand.
In those classes of machines or engines in which it is desirable to operate the con-
trolling valves from distant points, as elevators, and where such valves are actuated
by electricity, the engines are frequently subjected to severe strains from being abruptly
stopped and started, the controlling valves being shifted by single quick movements,
at once fully opening or closing the ports, and bringing the full force of the motor
fluid suddenly upon or cutting it off from the main piston.
Thus in the hydraulic elevator illustrated in Figs. 1 and 2, the main piston valve E
in the valve chest D controls the flow of motor fluid to and from the cylinder A con-
taining the main piston B, the rod of which is connected with the cage C by flexible
suspensories a.

page_text: The valve E is moved by an auxiliary engine G having a cylinder b, piston & con-
nected with the valve E by a stem p, valve chest g, and valve e controlling the flow of
motor fluid from a supply pipe h and thereby controlling also the shifting of the main
valve.
As shown the valve e is a rocking valve, and an arm on the valve stem is connected
to a spider carrying a series of cores i of solenoids I, electrically in circuit with a
battery, and with conductors leading to the cage C, where a suitable switch J serves to
make or brake the circuit through the wires to excite or discharge the solenoids and
thereby change the positions of the cores and of the valve e connected therewith.
Thus the solenoids are double, cach consisting of two sections and 4, and by exciting,
the sections 3 the cores are lifted to shift the valve and put the upper part of the
cylinder in communication with the supply pipe to depress the piston d. By exciting
the lower sections 4, the cores are depressed to reverse the valve and put the lower
part of the cylinder in communication with the supply and raise the piston d, and by
exciting both sections 3, 4, the cores are carried to central positions with both coils,
and the valve is set to cut off the flow of motor fluid and arrest the piston. The
sections are in line with a battery, and, a circuit may be completed to include the
battery and either or both sections through wires 5, 6, 7, by shifting the switch J in
the car C so as to connect with a terminal 9 of the wire 7, the terminal 10 of the wire 6,
or two terminals 10 and 11 of both wires 6 and 7.
<
It will be seen that each movement of the cores is instantaneous so that the valve e
is either opened, closed, or shifted by a single impulse, and the pressure of the motor
fluid is thrown on or off. so suddenly as to produce sudden shocks which are very
disagreeable to passengers in the cage and detrimental to the machinery. To obviate
these objections to the use of electrical valve moving devices I combine therewith a
valve, or cock, which I term a regulating valve," which is arranged to gradually
throttle or open a passage for the motor fluid prior to arresting or starting the engine,
so that the full force of the said fluid cannot be brought into action until the engine
has moved the cage for a short distance in one direction or the other, nor can it fully
cut off until the movement of the cage is greatly reduced, thus preventing shocks and
strains which would otherwise result.
The regulating valve is shown as a damper valve n arranged in the pipe h, so as to
nearly close the same when moved to a transverse position permitting a slight flow of
motor fluid, however, sufficient to start the engine when the valve e is opened.
The valve n occupies its transverse or closed position when the valve e is closed, and
the engine G is at rest, but is connected with the piston d or other moving part
of the engine so as to be opened after the piston has moved to a slight, extent in
either direction from its central position, and also to gradually close as the said
piston approaches a middle position. Different connecting means may be employed,
that shown consisting of a rod 7 extending from the piston d, through the head
of the cylinder b, and carrying the pivot of an arm pivoted at its other extremity
to the end of à pendant arm & fixed on the stem of a valve n.
When the valve n
is closed the arms will be vertical, and the arm 7 occupy a horizontal position,
and if the end pivoted to the rod y rises or falls the valve will be gradually
opened.
As shown in the drawing the main valve E closes the outlet port 19 from the main
cylinder, and the main engine is at rest but the operator in the cage has shifted the
switch J to the contact and the cores have been drawn down and the valve e
shifted to the position shown in Fig. 2. to throw the motor fluid below the piston d
to lift the valve E.
Instead of the sudden upward movement of the piston d and valve E, and the
equally sudden uncovering of the port 19, the valve so throttles the supply
pipe
that but a small volume of motor fluid can pass to the cylinder, and the
piston starts but slowly, but after a short movement of the piston & the draft
of the arm on the arms swings the latter outward until the valve n is opened
and permits the free flow of the motor fluid, the valve E being then quickly and
freely lifted to open the port 19. If now it is desired to close the port 19 the

page_text: operator shifts the switch J io the contact. 10 and the cores are lifted and the
valve e turned to carry the pressure to the top of the piston d when the latter
will be depressed, but before the valve E closes the port 19 the arm will swing
in the arms and the valve n is shifted so that the motor fluid is almost entirely
cut off as the valve E is brought to a position to close the port 19 and the final
part of the movement is made so gradually that the engine is brought to a stop
without any shock. The same results ensue if the valve E is moved downward
to open the connection between the ports 19, 20.
h
It is not essential to place the regulating valve in the pipe supplying the
motor fluid to the auxiliary engine, it may be put in the main pipe, supplying
the motor fluid to the main cylinder as shown in dotted lines Fig. 2, the valve
being shifted by two bearings, through the medium of a lever and and
connecting rod u¹, (dotted lines). The effect is the same in each case.
While a regulating valve in connection with an auxiliary engine and with electrical
valve shifting devices is illustrated and described it will be evident that it may be
effectively used to prevent shocks and strains if the main or auxiliary valves are
shifted in any other way. Thus in Fig. 3, the valve in the pipe is arranged
to be shifted by the movement of the stem of the main valve connected to be
operated as usual by a hand rope extending to the cage.
The second part of the invention consists in means for arresting the movement
of the cage should it acquire an excessive and undesirable rate of motion, and in
means for automatically releasing the cage when it is desired to resume operations.
The means for effecting these results is illustrated in Figures 4 to 9.
The main features of this device are, first, two pairs of levers carried by the cage;
second, clamps carried by the said levers, and adapted to grip vertical rails or guides
within the well, one rail extending between each pair of clamps; third an automatic
clamp controller, by the action of which the clamps are thrown into engagement with
the rails if the cage exceeds a stated rate of speed; fourth, a releaser whereby the grip
of the clamps upon the rails may be automatically released; and fifth, a restorer con-
sisting of means for resetting the parts in their original position to operate again
automatically should circumstances again so require.
The cage A is shown as connected to flexible suspensories to move between rails or
guides a, a, arranged vertically within the well. As shown each rail is a Tee iron or
bar, the web or central flange of which extends towards the cage. To the cage platform
are suitably pivoted two pairs of levers B, B, constituting the clamp carriers, each pair
terminating in two short jaws, which constitute or carry the clamps b, b, and between
each pair of clamps extends one of the rails a. As shown in the drawing the clamps
constitute parts of the levers and are curved at the outer edges, to prevent contact of
said edges with the flanges of the guide rails if the levers are tilted on their bearings
or fulcra when constructed as hereinafter described. Clamp controllers of different
constructions known in the art, may be employed to insure the gripping of the rails by
the clamps should the speed become excessive. In the construction illustrated the
controller consists of a screw shaft m for actuating the levers, a governor C and an
endless rope D normally travelling with the cage, connected with a driving wheel and
arrested by the action of the governor when the speed becomes excessive. Thus the
rope D travels between two eccentric clamps at connected with the governor so as
to be turned to grip the rope and hold it when the speed becomes excessive. The
rope passes round a drum h carried with the cage and when the travel of the rope is
arrested while the cage is moving the drum is caused to revolve and apply the safety
clamps.
Different means obvious to any mechanic may be employed for moving the levers to
apply the clamps by the rotation of the drum or driver wheel h. In the construction
shown the wheel gears with a pinion on a screw shaft m and the ends of the
opposite pairs of levers B, B, are coupled together as shown, and the screw shaft passes
through nuts, n², carried by the opposite levers and is provided with two reverse
threads adapted to the threads in the said nuts so that the rotation of the shaft, when

page_text: the cage descends after the rope is clamped, separates the nuts and with them the
inner ends of each pair of levers and applies the clamps to the rails, while the reverse
motion of the shaft carries the nuts towards each other, brings together the inner ends
of the levers and moves the clamps away from the rails.
The two reverse threads are preferably upon two parts of the shaft m of different
diameters, so that one nut n can be slipped over the reduced part of the shaft on to the
thicker part, and the other n' can be applied to the reduced portion and each nut
extends into a slot y in one of the levers and has a shoulder which rests against a
curved bearing of the lever, the ends of the levers overlapping or being forked and
one being slotted to receive a coupling pin projecting from the other, as best shown in
Fig. 5.
The application of the clamps to the rail, will arrest the cage, but to resume the
operation of the latter it is necessary to release the grip of the clamps and it is most
desirable to do this quickly and automatically without the aid of workmen, especially
in cases where the clamps have been applied as the result of excessive speed without
any fracture or disarrangement of the parts of the apparatus.
As the cage could not descend while the rails are gripped neither can it be raised
during the gripping of the rails if the clamps are immovably connected with the cage.
The clamps are therefore so supported that the cage can rise slightly independently of
the clamps and employ the restorer before referred to for resetting the clamps and
their connected parts on the upward motion of the cage, but as the gripping of the
clamps upon the rails places a great strain upon the connected devices and the friction
will prevent the restorer from acting, means are provided whereby when the cage is
lifted slightly and while the clamps still grip the rails, such lifting of the cage will
loosen the connections between the clamps and the restorer, thereby relieving the parts
of the strain and friction and enabling the restorer to act.
Thus the loosening of the connections may be effected by a change in the fulcra of
the clamp carrying lovers, causing their slight separation sufficient to relieve the strain
upon the parts. As shown in the drawings this is effected by the use of conical pivots
or bearings for the levers B, B, each of said pivots consisting of a conical pin c,
connected at the upper end to the cage, passing through openings in the lever and
carrying at the lower end a nut or bearing d, between which and the underside of the
lower lever is interposed a spring e, which tends to maintain the lever in position upon
that part of the pin having the greatest diameter.
When the levers are at the limit of their upward movement on the fulcrum pins,
their bearing points on the opposite sides thereon are further apart than when the pins
are drawn upward through the levers, when the latter are stationary, as results when
the cage rises slightly while the clanips are gripped to the rails, the lifting of the cage
and subsequent separation of the fulcra loosening the strain upon the levers slightly,
relieving the bite of the clamps upon the rails and permitting the restorer to act.
rope
The restorer is shown in the form of a spring t, secured at one end to the shaft m,
Fig. 6, and at the other to the shaft-bearing or to the platform, so that the spring is
put under tension by the turning of the shaft to apply the clamps, and when the
is released on the moving of the eccentrics a, a, therefrom, or the frictional stress is
removed from the threads of the shaft m by the automatic releasing of the clamps from
the rails, the spring tuncoils and restores the shaft and levers to the first positions, in
respect to the rails, while the springs e lift the levers to their upper position as soon as
the bite upon the rails is released.
It will be seen that as each pair of clamps is frictionally applied to bite the rail
between them with a gradually increasing friction, which yet permits a movement
of the clamps upon the rails until the cage is arrested, and as this friction is at
once released on the upward movement of the cage, a gradual stop and an automatic
release is obtained, an effect which is not secured when friction clamps are used
without any restoring device or where serrated eccentrics and ke stop devices are
used, such having the effect of stopping the cage with a sudden jolt that strains
the parts and injures the face of the guides.

page_text: Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed, as communicated to me
by my foreign correspondent, 1 declare that what I claim is :-
1. An elevator provided with a main valve and an electric valve, and a regulating
valve all constructed to operate substantially as and for the purpose set forth.
2. The combination in an elevator engine, of a main valve a regulating valve
therefor arranged in a supply pipe and connected with the main valve, and an
auxiliary valve operating engine provided with a valve connected with an electric
motor, substantially as described.
3. The combination in an elevator, of the main engine provided with a valve,
an auxiliary engine connected to operate the main valve, an electro-motor con-
nected to the valve of the auxiliary engine, and a regulating valve controlling the
flow of motor fluid to the auxiliary engine and connected with the main valve,
substantially as described.
4. The combination with the cylinder and piston of an elevator engine, and
with a valve controlling the movements of said engine and connected with the
cage to be operated therefrom, of a regulating valve in a supply pipe for said
engine connected with said controlling valve, substantially as described.
5. The combination with the piston and cylinder and main valve, and connec
tions between the latter and cage of an elevator, of a supplemental valve in a
supply pipe for said engine connected to the main valve shifting devices, to be
operated therefrom to fully open the said pipe after the main valve begins to
open its port, and close it before the main valve closes its port, substantially as
described.
6. The combination. with the main. valve, and auxiliary valve operating engine
of an elevator, of a regulating valve controlling the supply to the auxiliary
engine and connected with the main valve to be operated therewith, substantially
as described.
7. The combination with the elevator engine, of an auxiliary engine, the piston
of which is connected with the main valve, a supply pipe for said engine, and a
regulating valve therein connected to the piston rod of the auxiliary engine, sub-
stantially as described.
8. The combination of the main engine and main valve of an elevator, an
auxiliary engine and a supply pipe for said engine, and a regulating valve therein
connected with the main valve to move therewith substantially as described, the
arrangement being such as to gradually and automatically close the supply of motor
fluid to the auxiliary engine as the main valve takes its position to arrest the
movement of the main piston.
9. The cage provided with clamps, combined with a governor, and a clamp releasing
device, substantially as described.
10. The combination with the rails a and cage of an elevator, of clamp levers
'carrying clamps arranged to receive the rails between them and constructed and
connected with the cage to permit a limited upward movement of the cage in-
dependently of the clamps, a clamp controller, whereby the clamps are applied to the
rails when the speed of the cage becomes excessive, and a clamp restorer whereby the
clamps are reset to their first position after the strain on the clamps is released, sub-
stantially as described.
11. The combination with the rails a and cage of an elevator, of levers and clamps,
conical pins secured to the cage and constituting pivots for the levers, a controller for
applying the clamps to the rail automatically, and a restorer for resetting the clamps
when the grip is released, substantially as described.
12. The combination with an elevator cage, of rails a, clamps and levers B
connected with the cage to permit a limited upward movement of the latter indepen-
dent of the clamps to loosen the grip, an automatic clamp controller to apply the
clamps when the speed of the cage becomes excessive, and a clamp restorer to reset

page_text: the levers when the cage is moved upwards after applying the clamps, substantially
as described.
13. The combination of the rails a, an elevator cage, clamps, clamp levers, and
clamp controllers, and conical fulcrum pins for the levers, and springs supporting the
levers on the thicker portions of the pins, substantially as described.
14. The combination of the cage, conical fulcrum pins secured thereto, clamps,
clamp levers on said pins, and springs supporting the levers on the thickest parts of
said pins and clamp controller, substantially as described.
15. The combination with the cage and clamps of a threaded shaft carrying nuts
connected with the clamps, a driving wheel connected with said shaft, a travelling
rope and a governor provided with rope clamps substantially as described, whereby said
wheel is put into operation to turn the shaft when the speed becomes excessive,
substantially as described.
16. The combination with the rails, cage and clamps, of levers carrying the clamps,
and supported movably on conical pivots carried by the cage, and a clamp controller
connected with the clamps to apply the same when the speed of the cage becomes
excessive, substantially as set forth.
17. The combination with the cage, clamps, clamp carrying levers, and clamp
controller, of conical pivots for the levers supporting springs, and a restoring motor,
substantially as set forth.
18. The combination with the cage, clamps, clamp levers, and driving wheel
thereof, of a travelling rope passing round said wheel, a governor driven by said
rope, rope clamp connected with said governor, and a restoring spring for resetting
the clamps to their normal position, substantially as set forth.
19. The combination with the clamps and clamp carrying levers B, B, pivoted below
the cage, of the nuts, threaded shaft, driving wheel travelling rope and governor,
and a spring connected with the shaft and with a stationary support, substantially as
set forth.
20. The combination with the cage, clamps, conical fulcrum, pins and springs, of a
driving wheel connected with said clamps, a restoring spring, a governor, a travelling
rope passing round the driving wheel and governor wheel, and rope clamps connected
with the governor, substantially as set forth.
Dated this 26th day of September 1888.