Improvements in Electric Lifts, Hoists, Capstans, and the like.
Year: 1897

page_text: PROVISIONAL SPECIFICATION.
Improvements in Electric Lifts, Hoists, Capstans, and the like.
I, ALFRED SOAMES, of 16, Red Lion Street, Clerkenwell, in the County of
Middlesex, do hereby declare the nature of this invention to be as follows:-
:―
The object of this invention is to enable induction motors actuated by an
alternating current to be used for operating lifts, hoists, capstans and the
like.
If electric motors of this class have to be started each time that the cage
has to be raised, some little time elapses before the motor attains sufficient speed
to run synchronously with the current and during this time a very large supply
of current is required and sudden disturbances are thereby introduced into the
supply maius motors of this class are therefore rarely used for working lifts.
According to my invention I arrange for the motor to be kept running con-
tinuously whether it be raising the cage of the lift or not and at the same time
in order that there may not be serious waste of power during the times when
the motor is not doing work I employ a choking coil which can be switched in and
out so that when the motor is not doing work the energy absorbed is diminished by
the action of the coil-the motor I may also provide with a fly wheel to keep the motor
Thus
rotating uniformly at the times when the choking coil is switched in or out.
the motor can without serious loss of energy be kept running constantly and ready
to perform work so soon as the choking coil is cut out from the circuit. Or in
place of a choking coil I may similarly switch in or out a transformer to transform
down the volts to say half the working pressure. Or I may form the motor with
two or more windings which can be put in series when running light and in
parallel or only one used when full work is on.
Improvements in Electric Lifts, Hoists, Capstans, and the like.
I. ALFRED SOAMES, of 16, Red Lion Street, Clerkenwell, in the County of
Middlesex, 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 of this invention is to enable induction motors actuated by an
alternating current to be used for operating lifts, hoists. capstans and the

page_text: If electric motors of this class have to be started each time that the cage has to
be moved some little time elapses before the motor attains sufficient speed to run
on load.
According to my invention I arrange for the motor to be kept running con-
tinuously whether it be moving the cage of the lift or not and for the motor when
not moving the lift to be kept running without serious loss of energy at such
a speed relatively to the alternations in the current as to be capable of at once
picking up its full speed and performing work when current is switched on to
the motors working coil or coils only.
Although my improvements are mainly applicable where induction motors are
used yet they can also be used with other forms of electric motor actuated by
alternating currents.
The drawing annexed shews my invention applied in the manner I prefer to
one form of lift mechanism actuated from a continuously running shaft but I do
not restrict myself to applying it to this form of lift.
Diagram A shews the general arrangement of the lift to which my invention is
applied and Diagram B the switch mechanism used therewith for carrying out my
invention.
In this form of lift A is a pulley which is kept running continuously. BB are
driving belts one crossed the other uncrossed pasing from the pulley A to fast
and lose pulleys on a shaft C so that by shifting the driving belts either to one
side or the other the shaft can be driven either in one or other direction-or
be allowed to remain at rest when the belts are in an intermediate position as
shewn in the drawings. The shaft Ceither has a drum upon it on which is wound
a rope which passes to the cage of the lift or other means are provided for
conveying movement from the shaft C to the cage. I is a brake which is applied
to a pulley on the shaft C whenever the driving belts are in their intermediate
position and both off the fast pulley C E is a sliding bar by which the driving
belts can be moved either to one side or another. The bar has a toothed rack
upon it into which gears a pinion F on the axis of a pulley around which passes
the ordinary hand rope which extends from top to bottom of the lift shaft passing
through the cage and which can always be pulled in one or other direction by
anyone in the cage.
Anyone in the cage can thus by shifting the rope in one or other direction shift
either one or other of the driving belts on to the fast pulley C or bring then into
an intermediate position so as either to raise or lower the cage or bring it to
rest. GG are two cords attached to the sliding bar E one on either side of the
brake and which are both led over guide pulleys H and then downwards and
attached to the brake lever. When the sliding bar E is shifted endwise to shift
the driving belts in either direction from their intermediate position either one cr
other of these cords is tightened up and the weighted end of the brake lever is
raised and so the brake is put out of action.
The pulley AI drive continuously by a motor actuated by an alternating electric
current preferably I use an electric motor such as is described in the Specification
of a former Patent granted to me No. 7772 in the year 1897.
In this motor there are two sets of coils the running set of coils of comparatively
few turns and the starting set of coils of a greater number of turns.
In Diagram B of the drawings I indicates the running coil of the motor and J
the starting coil.
To put the motor into motion when working hours are about to commence
current is supplied to the motor through a switch K by which when the switch arm
is inclined in the position shewn current passes from the main to
both sets of coils and through a resistance L in the circuit of the running coils.
This causes the armature to revolve and when it has acquired sufficient speed to
allow it to run synchronously or continuously with current supplied to a single
set of coils only the switch arm is inclined over in the opposite direction current
then passes through the switch arm of a second switch M to the fine or starting

page_text: coil only and the armature is kept rotating without material loss of energy.
The switch arm of this second switch M is as shewn coupled to the lever arm of
the brake 1 so that whenever this arm is raised to take off the brake the arm of
this second switch is raised also and its end shifted from off the contact N on to
the contact current then passes through the working or running coils I of the
motor and the motor is at once capable of performing useful work and the cage is
raised or lowered--so soon as the movement of the cage is arrested by both driving
bands being brought on to the loose pulleys and the brake 1 being applied the
switch arm of the second switch M is again lowered to the contact N and the
current then again passes through the fine coil J and the armature continues to
revolve without material waste of energy.
In place of lowering the no load consumption in the above way the automatic
switch might be arranged to cause the current supplied to the working coil to pass !
through a choking coil when the motor is to be kept running without doing work
and to cut out this choking coil when the motor is required to perform work.
Or the motor might be wound with two sets of running coils and the switch he
arranged to pass the current in parallel through these coils when the motor is to
perform work and through the coils in series when the motor is running light.
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. A lift hoist capstan or the like actuated by an induction alternating current
motor kept constantly running and in which whenever the motor is disconnected
from the lifting mechanism to put the lift out of action a switch is moved
automatically into a position in which only sufficient current is allowed to pass
through the field windings of the motor to keep its armature rotating without
material waste of energy at sufficient speed to allow of its at once acquiring a
proper speed to run with the current and perform work so soon as current is
supplied directly to its working coil or coils.
2. In lifts actuated from a shaft kept running continuously and in which the
raising or lowering or bringing to rest of the lift cage can be brought about
either by putting the lifting mechanism into gear with the continuously running
shaft or throwing it out of gear, the driving of such continuously running shaft by a
motor actuated by alternating electric current supplied through a switch which when-
ever the lifting mechanism is put out of gear with the continuously running shaft is
automatically brought into such a position that the direct passage of current to
the running or working field winding coils of the motor is cut off and only enough
current allowed to pass any of the field windings to keep the motor revolving at
sufficient speed to allow of its acquiring a proper speed to run with the current and
perform work so soon as current is again supplied directly to its working coils.
3. Lift mechanism constructed substantially as herein before described and illus-
trated in the drawing annexed.