Improvements in Suspended Lifts or Elevators.
Year: 1891

page_text: Date of Application, 11th Dec., 1891
Complete Specification Left, 12th Sept., 1892-Accepted, 15th Oct., 1892
PROVISIONAL SPECIFICATION.
Improvements in Suspended Lifts or Elevators.
I, EDWARD WILLIAM ANDERSON of Raydon Lodge, Erith in the County of
Kent, Engineer, do hereby declare the nature of this invention to be as
follows:-
This invention has for its object improvements in suspended lifts or elevators.
I apply safety gear to the balance weights of lifts, so that in the event of a
balance weight rope or chain breaking, the weights will be caught on their guides,
and prevented from falling and doing damage. I provide for the automatic
stopping of the lift by means of tappets or stops on the valve or switch ropes or
rods which are acted upon not only by the cage but also by the balance weights,
so that in the event of the tappet actuated by either cage or balance weight,
slipping or from any cause failing, the other tappet is still available and will stop
the lift, or if the cage or balance weight either sticks in descending or the ropes
break and prevent it working its tappet, the other will operate.
I apply a spring or weighted friction coupling or clutch in lifts driven by means
of worm gearing; this coupling or clutch is introduced between the worm gear
and the rope drum or pulley, so that in the event of a sudden stoppage or start,
the coupling or clutch will slip a little and relieve the strain on the worm teeth.
The coupling or clutch I so construct that it cannot possibly allow the lift to
run away altogether, it having stopping arrangements on it to prevent slipping too
far without engaging in a permanent stop for driving positively.
In electrical or other lifts, in order to equalize the work in ascending and
descending, and so reduce the size, strength and cost of motors, generators and
gear, I overbalance the cage to the extent of about one half the weight of the
Toad to be lifted, so that, if fully loaded, the work ascending and descending
will be equal.
In electric or other lifts driven by endless chains or ropes, I suspend the motore
actuating the chain or rope drum, in slides or cradles suitably weighted so that the
ropes are always kept by the weight uniformly stretched and taut for gripping the
drums. In short stroke lifts I coil the lifting ropes upon each end of a wide
barrel, so that the resultant pull is vertical, and no side stress is put on the guides.
The balance weight ropes I arrange in a similar manner.
For increasing the grip of lift ropes upon driving pulleys I arrange that the
ropes shall pass over a gripping groove on the driving pulley then back round a
guiding pulley, and finally round a second groove in the driving pulley and thence
away to the lift.
The number of grooves in the guiding pulley and in the driving one may be
increased to increase the grip.
Dated this 11th day of December 1891.
CARPMAEL & CO.,
Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Suspended Lifts or Elevators.
J, EDWARD WILLIAM ANDERSON, of Raydon Lodge, Erith in the County of
Kent, 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 :-
In electric or other lifts driven by endless chains or ropes, 1 suspend the motors

page_text: actuating the chain or rope drum, in slides or cradles suitably weighted so that
the ropes are always kept by the weight uniformly stretched and taut for
gripping the drums.
This arrangement is illustrated by the drawings annexed.
Figure 1 is a side elevation with parts removed of an electric hoist in accordance
with my invention.
Figure 2 is a vertical section and Figure 3 is a sectional plan of the same.
a is the cage of the lift bb are endless ropes by which the cage a and counter-
weights care suspended, they may be four in number or otherwise according to the
mode of suspension. d is an axis with pulleys to receive the endless ropes at the
head of the lift. e is another axis with similar pulleys at the bottom of the lift.
The axis e is carried in bearings fon a frame which is shewn separately in plan by
Figure 4 and which is capable of sliding in a vertical direction between the guide
columns 9 9.
hh are two electro motors carried by the frame, their axes are
vertical and are furnished with worms h¹¹ which engage with a worm wheel e¹
on the axis e.
By means of the electro motors the axis e can be driven in either direction to
raise or to lower the cage the needful tension on the ropes 6 being maintained by
the weight of the electro-motors and their frame which hang suspended, auxilliary
weights being attached in addition if necessary.
When the electro-motors are not driven the cage will remain at rest, the worms
serving to lock the worm wheel.
In order to equalise the work in ascending and descending, and so reduce the
size, strength and cost of motors, generators and gear, I overbalance the cage to
the extent of about one half the weight of the load to be lifted, so that, if fully
loaded, the work ascending and descending will be equal.
The worm wheel e' is not fast on the axis e but engages therewith through a
coupling or clutch the frictional surfaces of which are pressed together by a
spring. This coupling or clutch is introduced between the worm gear and the
rope drum or pulley, so that in the event of a sudden stoppage or start, the
coupling or clutch will slip a little and relieve the strain on the worm teeth.
The coupling or clutch 1 so construct that it cannot possibly allow the lift to
run away altogether, it having stopping arrangements on it to prevent slipping
too far without engaging in a permanent stop for driving positively.
kis a stop pin which serves this purpose; it is fitted into one part of the clutch
and its end enters a corresponding groove in the other part.
Figure 5 is a side elevation and Figure 6 is a vertical section shewing an
arrangement which I sometimes employ to increase the grip upon the pulleys of
endless ropes by which the cages of lifts are suspended.
For increasing the grip of lift ropes upon driving pulleys I arrange that the
ropes shall pass over a gripping groove on the driving pulley then back round a
guiding pulley, and finally round a second groove in the driving pulley and thence
away to the lift.
e is the driving axis as in the arrangement shewn by the preceding figures.
e2 are the driving pulleys upon the axis e. 11 are guiding pulleys upon an axis
which is carried in stationary bearings. The endless ropes & beach descend from
the lift to one of the driving pulleys e³, passes beneath this pulley in one of its
gripping grooves, then ascends to the guiding pulley 1 passes over the guiding
pulley and again descends to the same driving pulley passes a second time
beneath it again in a nipping groove and thence ascends.
The number of grooves in the guiding pulley and in the driving one may be
increased to increase the grip.
In some cases I dispense with pulleys with gripping groves and employ instead
a winding barrel at the top of the lift as is shewn in Figure 7. As is here seen I
coil the lifting rope upon each end of a wide barrel from which the rope descends
and passes beneath a pulley centrally placed upon the cage over its centre of
gravity. From this arrangement it results that the resultant pull upon the cage

page_text: is vertical and no side stress is put on the guides between which the cage travels.
The balance ropes I arrange in a similar manner; they may be coiled in the
opposite direction upon the same barrel if the width of the barrel be sufficient or
they may be coiled on a second barrel connected with the first by gear wheels.
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 suspended lifts or elevators where the cage and counterpoise are raised
and lowered by endless ropes passing around driving pulleys; the means herein
described for maintaining the tension upon the endless ropes necessary to cause
them to bite in the gripping grooves of the driving pulleys; such means consisting
in suspending by the endless ropes, the driving pulleys with their axis and the
motor which drives the axis.
2. In suspended lifts or elevators where the cage and counterpoise are raised
and lowered by ropes actuated by pulleys or drums upon an axis driven and held
by a worm wheel and worm; the means herein described for relieving strain in
the event of sudden stoppage or start consisting in connecting the worm wheel and
its axle by a friction clutch provided with a pin or stop limiting the independent
movement of the parts.
3. In suspended lifts or elevators where. the cage and counterpoise are raised
and lowered by ropes actuated by pulleys or drums driven by an electro motor;
the means herein described for equalising the load upon the said motor consisting
in providing a counterweight or weights which overbalances the empty cage to the
extent of one half of the load or thereabout.
4. In suspended lifts or elevators where the cage and counterpoise are raised
and lowered by endless ropes actuated by a suspended electro-motor; the means
herein described for obtaining increased grip upon the driving pulleys; such means
consisting in providing guiding pulleys and causing the endless ropes to encircle
these guiding pulleys and return to the driving pulleys.
5. In lifts or elevators suspending the cage and counterpoise substantially as
herein described from a wide barrel by lifting ropes coiled upon the barrel and in
such manner that the resultant pull upon the cage is vertical and no side stress is
put upon the guides.
Did this outh dove of toust 1000
E. W. ANDERSON.