Improvements in Machinery and Apparatus for Raising and Lowering Weights, especially Passengers and Goods.
Year: 1895

page_text: Date of Application, 19th Apr., 1895
Complete Specification Left, 19th Feb., 1896-Accepted, 4th Apr.,
1896
PROVISIONAL SPECIFICATION.
Improvements in Machinery and Apparatus for Raising and
Lowering Weights, especially Passengers and Goods.
I, CHARLES ARTHUR ALLISON, of 52 Chancery Lane, London, in the County
of Middlesex, Patent Agent, do hereby declare the nature of this invention (which
has been communicated to me from abroad by Cofran Israel Hall, of San
Francisco, State of California, United States of America, Engineer) to be as
follows:-
This invention consists in the application in various analogous ways of motive
power to hoists, especially in cases where the platforms or cabins are over counter-
weighted, so power applied in operating will be as nearly as possible equal for
upward and downward movement. Such counterweights being commonly equal to
the weight of the cabin or platform and one-half of an average service loan
thereon.
Various modifications of my apparatus are required, all being the same in nature
and results, but adapted to the varied situations, kind of motive power applied and
means of producing the static strain required in my system.
In one case I suspend the cabin or platform on ropes passing over pulleys at the
top, and on the other end of these ropes apply a simple counterweight, as before
explained.
Connecting the bottom of this cabin or platform and the counterweight, I apply
other ropes that pass between the two around impelling pulleys that drive the ropes
by friction or traction, hauling the cabin or cage and the counterweight reversely
upward or downward by means of an electric motor, or any other suitable source
of driving power applied to these friction or traction pulleys.
Instead of there being two sets of ropes, one will answer if the strands pass
through or by the cage or cabin and counterweight. I speak of two sets because
they are so divided for constructive reasons.
To maintain the strain required for traction I so arrange the impelling machinery
that some portion of its weight will rest upon or within the bight of the impelling
ropes, and then regulate the movement and strain thus caused by means of a
hydraulic cylinder having in part the functions of what is called a "cataract."
In another modification I employ, instead of an excess counterweight, water
pressure, applied on a piston to which is attached the usual system of multiplying
pulleys or sheaves, known as the Armstrong system. The water pressure is
preferably produced by air confined in a receiver, containing also water, the latter
being circulated between the receiver and the hydraulic cylinder before named, by
a positive pump of some kind to which the driving power is applied.
This pump being capable of acting in either direction, the water is sent from the
receiver into the hydraulic cylinder, or the reverse, as the load is to be raised or
lowered, the static balance due to the air pressure in the receiver remaining
constant, and thus dividing the resistance between raising and lowering.
In other cases I employ instead of a pump between the receiver and the
hydraulic cylinder a second hydraulic cylinder and piston to circulate the water
between the two, but in that case I employ a differential or trunk piston in the
main cylinder, the differènce of area on the two sides representing the excess
counterweight, and producing the static pressure or strain upward on the cabin or

page_text: platform. The auxiliary hydraulic cylinder and piston are driven by a screw or
rack impelled by suitable motive power. The auxiliary piston communicates on
one side with the annulus around the trunk of the main piston, or on its reduced
area, so that the movement of the main actuating piston coincides with and follows
all movements of the auxiliary one, the static counterweight, due to the difference
of area on the two sides of the main piston, remaining constant as in the cases
previously described.
I also in other cases attain these same functions by employing a single acting
hydraulic cylinder and piston, with the usual pulleys and ropes to multiply the
movement of the hydraulic piston, and applying to one side of the piston a static
pressure, sufficient to counterweight the cabin or platform and half of an average
service load, and then connecting to the main piston or its rod by means of screws,
operated by power derivable from an electric or other motor.
In this case I place two screws parallel with the piston rod, passing through nuts
on the pulley cross-head, so that by revolving the screws the piston and piston rod
are moved outward or inward, and the load raised or lowered, the static counter-
balance acting all the time, and dividing the resistance between the upward and
downward movements of the load.
In this case, as in others, I employ by preference a receiver containing air and
water to produce the static pressure or counterweight, but such pressure can of
course be drawn from a head or in other manner, and act the same.
I also accomplish the before-named functions by applying the actuating or the
service work it may be called, by friction or traction in or on the strands of ropes,
arranged on what is known as the Armstrong system. In this case I employ a
Bydraulic piston under a static pressure, on one side or in one direction, the same
as in the previous cases described, to produce the excess counterweight for the
cabin or platform and the load thereon, and by leading a strand or strands of the
multiplying rope around separate traction drums, to which the impelling power is
applied, attain the desired result, that is, a movement of the lead upward or
downward with approximately the same amount of power each way, and by means
of the bydraulic elements secure locking and abutment against false movements or
falling.
In some cases, when hydraulic apparatus is employed, I derive the immediate
actuating power from the water pressure, applied on a wheel or motor, and then
maintain the water pressure by a small engine or notor acting continually, so the
prime motive power becomes practically constant, and is reduced in capacity
accordingly.
Dated thin 10th of : 1005
ALLISON BROS.,
Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Machinery and Apparatus for Raising and
Lowering Weights, especially Passengers and Goods.
-I, CHARLES ARTHUR ALLISON, of 52 Chancery Lane, London, in the County
of Middlesex, Patent Agent, do hereby declare the nature of this invention (which
has been communicated to me from abroad by Cofran Israel Hall, of San
Francisco, State of California, United States of America, Engineer) 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 improvements in machinery and devices for hoisting
and lowering passengers and goods, and to gearing operated through or by
hydraulic apparatus, and a variable driving power derived from electric motors,

page_text: steam or other source; especially to hoists or elevators wherein the cage and some
predetermined part of the load is balanced, so the driving power can be as nearly
as possible divided between raising and lowering movements.
The essential feature of my invention is in the transmission of power through
hydraulic apparatus, instead of direct by gearing and ropes, to a cage or load to
be raised or lowered, so that while the power is indirectly applied there will be the
advantage of positive movement and abutment, or sustention against danger of
falling, and other features of the hydraulic system of operating hoists or elevators.
Stated in general terms, my invention so far as perfected includes:
(1) The employment of a piston under static fluid pressure derived from water
or oil contained in a receiver or supplied from a head, so as to impart a constant
force on a main piston to which the multiplying or actuating gearing is attached,
such pressure being sufficient to raise, as nearly as can be adjusted, the cabin and
the full service load, or some predetermined part thereof.
(2) The application of the same main piston of variable counter-pressure, either
fluid or by direct mechanical means, in proportion as the load to be raised or
lowered may require. Such pressure being positive or negative, inward or outward,
as will be hereinafter explained.
(3) In varying the direct pressure on the main actuating piston by means of
fluid impelling apparatus placed between this main piston and the source of supply,
so that the pressure on the piston can be increased or diminished above or below
what is due to the static head or pressure before named.
(4) In the method of applying and controlling this counter or auxiliary pressure,
also the manner of its operation, varied by the mechanical means employed. For
example, if counter pressure is by fluid action there can be utilized some portion
of a descending load greater than is required to overcome the friction of the
machinery, as will hereinafter be explained.
(5) In so arranging the various forces on the main actuating pistons that no
counterweights are required for the cages or platforms, this function being provided
for in the hydraulic elements of the machinery.
Referring now to the drawings herewith.
Fig. 1 shows in side view an elevator or hoisting apparatus in which my invention
is applied in its most simple form, that of varying the direct pressure on the main
actuating piston, no counter pressure being applied.
The cylinder A¹ is of the usual construction, open at one end, and provided with
a piston B', and a piston rod C¹. On the outer end of the piston rod C¹ is a
frame D in which is mounted rope sheaves or pulleys E¹, corresponding to another
set of rope sheaves or pulleys E2 supported on the cylinder cover F¹. Around
these pulleys E' E2 is rove a rope G₁ that extends upward and over an idle pulley
to the load to be raised or lowered in the usual manner.
H' is a tank or receiver partially filled with water or other liquid, and partly
with air under pressure, so as to maintain an elastic pressure or tension therein.
A pipe I' leads from the receiver H' to a common rotary pump J', and a second
pipe 12 from the pump J to the chamber L of the main cylinder A. The
pump Jis driven by a band K, and is, arranged to revolve in either direction, so
as to force the fluid from the receiver H' to the chamber L', or the reverse, and
thus cause the piston B¹ to move out or in and raise or lower a load accordingly.
This receiver H' can be substituted by a connection with any source of water
supply under constant or static pressure such as the water supply of a city or town,
or a tank placed at sufficient elevation. I however use throughout in the various
figures of the drawing a vessel filled with air and water.
When the force on the piston B due to the static pressure on the receiver H' is
sufficient to raise the load, the pump J has no function except to pass the fluid,
and requires no power, but if the load is greater than this pressure will raise, then
the pump J supplements the pressure in the receiver H¹, and power is applied by
the belt K to make up the required force.
In lowering a load, the pump J¹ is started in the opposite direction, and if the

page_text: load is heavy enough the water in the chamber L' is expelled through the pump J
by the inward movement of the piston B¹. If however the load to be lowered
is not sufficient to expel the water from the cylinder A¹ against the pressure in the
receiver H¹, then the pump J¹ supplements this lack of power and forces the water
back to the receiver H, but consumes no more power in so doing than is required
in addition to pressure of the load on the piston B¹.
In this manner it may be seen the cage or platform and half an average load
thereon is counterbalanced by the static pressure of the fluid, and the power applied
is only what will overcome the frictional resistances and the variations of load
above and below a predetermined one.
The pressure in the receiver H' is maintained by forcing in air or fluid to make
up for any leaks that may occur, there being no other waste because the fluid is
merely circulated.
Referring to Fig. 2 of the drawings this represents another method of my
invention by means of a static pressure to balance the total load and applying a
counter pressure to compensate for the variable loads, As being the main cylinder,
B the main piston, and M a trunk piston formed integrally therewith.
E E are sheaves or pulleys around which the rope G is rove in the usual
manner, so as to multiply the movement of the load suspended by the rope G³,
that extends over an idle pulley to the cage or platform on which the load is
placed, the same as Fig. 1, as explained. He is a receiver or tank containing air
and fluid, as in Fig. 1, and is connected with the chamber L' of the cylinder A²
by means of a pipe I, a valve or cock N' being provided to cut off this communica-
tion at certain points as will be hereinafter explained.
Connected with the main cylinder A' is a second one A³, the contents of which
equal the annular chamber around the trunk M. One end of this cylinder A³
is connected with the receiver H2 and the chamber L³ of the cylinder A³, by means
of the pipe 13, and the other end by means of a pipe I with the annular chamber O,
both ends always being filled with the fluid. This cylinder A³ contains a piston B³
operated by the piston rods C C³, and a screw P¹ driven by the pulleys Q, which
are arranged to run right or left, and thus force the piston 133 outwards or inward
accordingly.
The operation is as follows:
Supposing the chambers L L L and annulus O being all filled under pressure
from the receiver H2 which is partially filled with air and water under pressure.
The piston B would be in equilibrium, but the main one B would be sustaining
on one side a pressure due to its full area next to the chamber L2, but on the other
side would be subject only to a pressure due to the section to the annular chamber 0,
so there would be an outward thrust on the trunk M equal to the area of its cross
section multiplied by the pressure in the receiver H, less the pressure in the
annular chamber 0, and a corresponding thrust on the pulley E³, and draught
downward on the rope G⁹.
The proportions are so made in respect to the pulleys E³ E, and the pressure in
the receiver H2, and areas of the pistons and trunk M, that this downward strain
on the rope G2 is equal to the cabin or platform one half an average service load
to be raised by the machinery or in other words the machinery and parts as shown
require a strain on the rope equal to all the load G2 of half less one half the
service load to put the whole into equilibrium.
If it is desired to ascend with a load, the valve N₁ is opened and the pulleys Q
are put in motion in such a direction as will force the piston B³ inward, thus
expelling the contents of the chamber L³ into the pipe I, and at the same time
drawing the fluid and pressure from the annular chamber O in the cylinder A².
This permits the pressure in the chamber L to exert a full force ou the piston B',
and consequently on the trunk M, pulleys E³, and on the rope G2, equal to the area
of B2 multiplied into the pressure in the receiver H³, so as to raise a maximum
load, the power applied to the pulleys Q reducing the pressure in the annular
chamber O, by producing a vacuum therein.

page_text: If a load is to be lowered then the pulleys Q are started in the reverse direction
so as to draw the piston B³ outward, and force the liquid from the chamber L* into
the chamber O, driving the main piston B2 inward expelling the water in the
chamber L³, through the pipe I into the receiver H³, and so much as is required
into the chamber L³.
In this manner it will be seen that the movements in the main piston B² follow
those of the supplementary piston B³, and the load on the rope G³ is moved up or
down accordingly.
The valve or cock N' can be connected by tappets or in other suitable manner,
with the cage or platform to be raised and lowered, and acts as an automatic stop
at the extreme range of movement, and independent of the gearing that controls
the motion of the pulleys Q and the piston B³.
In this method of operating the same as shown in Fig. 2, it will be obvious
that the cylinder or pump A³, and the piston B³, with its connected gearing can be
substituted by a reversible pump, such as shown in J¹ Fig. 1, and thus attain the
same functions and results. Such substitutions and modifications to meet the
various circumstances of application, I do not illustrate in the drawings because.
obvious to those skilled in making such apparatus.
Referring next to Fig. 3, representing another plan of hoisting or elevator
apparatus operating according to my invention.
A is the main cylinder, and B' the actuating piston, the latter connected with
the piston rod C with a movable crosshead R¹ that supports the multiplying
pulleys E, corresponding to another set of pulleys E mounted on the rear
cylinder head F³
His a tank or receiver as before, containing air and water or oil under pressure,
the latter passing through the pipe I to the chamber L, pressing on the inner side
of the piston B, such pressure being in proportion to the tension in the receiver H³.
This pressure on the piston B4, piston rod C, crosshead R', and pulleys E' is, as in
the case of Figure 1 applied to a cage or load, and the pressures and areas s0
arranged so that this strain is equal to the cabin or platform and half the average
service resistance or weight to be raised or lowered.
As however such load varies there is provided a supplemental power, in this case
an electric motor or motors T₁ T, that act on the crosshead R' by means of a
train of gear wheels and the screws U₁ Us, as seen in the drawing. The pinions S S.
mesh into the driving wheels V1 V2, W being an intermediate wheel to cause
coincident motion of the screws U₁ U³.
The two motors T¹ T, are provided with the usual reversing apparatus, causing
them to revolve in either direction, in series or multiple as the speed and power
required may demand. If a descending load is not enough to force the piston B
inward, and expel the fluid from the chamber L to the receiver H³, the motors T¹T"
supply the deficiency of power. In raising heavy loads if the force of the fluid in
the chamber L and on the piston B' is not sufficient, then the motors act in opposite
direction, drawing the piston B* outward, and raising the load.
The valve or cock N' is employed as a positive stop at the extreme of the upper
and lower strokes of the cage or load to be raised or lowered, or to lock it at any
intermediate point, and is operated automatically by tappets, or other gearing, on
the cage or platform, thus rendering the range of movement independent of stopping
and starting the motors T T2. The chamber L behind the piston B4 is open to.
the atmosphere and provided with a drainway at the bottom.
Referring next to Fig. 4, which represents another method of applying my
invention, the drawing is a plan view of a hydraulic cylinder and its attendant.
gearing for operating an elevator, supplemented by an electric or other motor, as.
in the previous cases described, but acting on the hoisting ropes instead of on the
pistons or other reciprocating parts of the gearing.
The cylinder A is of the common construction, such as herein before shown in
section in Figures 1 and 3 for example, containing a piston and piston rod C³,.

page_text: connected to the crosshead R2, the inner end of the cylinder A being connected
by the pipe I with a receiver H, as in the previous figures.
In the crosshead R' is mounted a set of multiplying pulleys E', corresponding to
an opposite set of similar pulleys EB at the other end of the cylinder A. Around
these pulleys is rove a rope in the usual manner extending to a cage or platform for
passengers or goods to be raised or lowered.
On the shafts X' X', to which the sheaves a and b are keyed, there are two spur
wheels YY, and meshing into these wheels are pinions c and d on the shafts of f
and g.
On the shafts and g are the spur wheels m and n engaged in the pinion e
on the shaft or spindle h, to which an auxiliary power is applied from an electric
motor, or other source such as may be available.
In this manner it will be seen that by revolving the shaft h, the spur wheels Y' Y'
and the pulleys are turned in the same direction, and will impel a rope wound
thereon.
If the amount of traction imparted by the pulley a is not sufficient for the load
to be raised or lowered the rope can also be wound about the pulley 6 which is also
impelled by the auxiliary driving power and then pass on to the pulleys E7 thus
increasing the driving power.
In operating, the receiver His charged with air and water or oil up to the
desired pressure, and such pressure forces the liquid through the pipe 15 into the
cylinder A³, exerting a pressure on the piston therein, and on the piston rod C³
and pulleys E', in proportion to the areas and pressures, which are arranged to
balance a tension on the lifting rope equal to the weight of the cabin or platform
and one half the average service load to be raised or lowered, so that in raising or
lowering, auxiliary power required and furnished from the shaft or spindle.h will
only be enough to overcome the frictional resistance of the various moving parts,
and the variations above and below this assumed load.
The stop cock or valve N³ is employed as a means of stopping the movement at
the upper and lower ends of the stroke of the platform or cage, or for locking
them at any intermediate point of their range.
In all these modifications it may be seen, as set forth at the beginning, that the
essential elements are a hydraulic piston sustaining a certain initial pressure, which
pressure is equal to raising the cabin or platform and some predetermined load
thereon, and that the hydraulic power is supplemented by other power when the
maximum load is to be raised or the minimum load is to be lowered, and that the
usual counterbalance weights can be dispensed with.
These several methods of applying my invention depend upon the circumstances
of erection and use and are here set forth to enable them skilled in making such
apparatus to understand fully and completely the nature and objects of my
improvements and the manner of their application in practice.
Instead of the screws and spur gearing shown in Fig. 3, the piston rod C¹ can
be made with a toothed rack to run a spur pinion or spiral one in the manner of a
worm gearing, and the motive power be applied directly to the shaft or axis of such
pinion, and in this manner simplify and reduce the amount of gearing between the
motive power and the piston rod C, the effect being the same however the reducing
and connecting gearing is arranged.
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 :-
First. In hoisting and lowering apparatus, an hydraulic engine the piston of
which is subjected on one side to a constant fluid pressure, such pressure being
sufficient to raise a cabin or platform and some predetermined load therein or
thereon, a pump or other hydraulic apparatus to increase or diminish the pressure
on the piston, or the application of a supplementary force to such piston or its
connections, so a maximum load can be raised, or an unloaded cabin or platform

page_text: can be lowered, in the manner substantially and for the purposes herein set forth
and explained.
Second. In hoisting and lowering apparatus a hydraulic engine the piston of
which is subjected to constant fluid pressure on one side sufficient to raise a
maximum load, said piston provided with an enlarged or trunk piston rod at one
side, passing through a packing gland, forming an annulus on one side of the main
piston, a fluid connection through a pump or any fluid impelling apparatus between
the annulus and any source of fluid pressure equal to that of the main supply, so
that by action of the pump, the pressure in the annulus can be diminished as the
piston moves outward, or increased as the piston moves inward, and as the load is
hoisted or lowered in the manner substantially as herein described.
Dated this 10th dow of Fahr 1806
ALLISON BROS.,
Agents for the Applicant.