Differential Self-sustaining Lifts.
Year: 1890

page_text: Date of Application, 18th Sept., 1890
Complete Specification Left, 18th June, 1891-Accepted, 22nd Aug., 1891
PROVISIONAL SPECIFICATION.
Differential Self-sustaining Lifts.
WILLIAM TROW 21 Chapman Road Small Heath Birmingham Engineer do
hereby declare the nature of this invention to be as follows:-
This invention consists of improvements in lifts, whereby any break-power is
dispensed with. A shaft or spindle, working in bearings supported on two or more
bearers at the top of guide posts, to which is attached a hauling wheel and endless
rope for hand power, or band pulleys, for steam power, and friction wheels. On the
same shaft are also two V pulleys of different sizes, and made at a proper angle to
prevent the rope from slipping, or recessed to receive the links of a chain. These
wheels are keyed to the shaft or spindle. Over the wheels or pulleys run an endless
rope or chain, passing under a single pulley attached to top of cage and over two
loose pulleys revolving on a spindle attached near the top of guide posts, thence
down and under a pulley secured to the top of a balance weight, so that when the
shaft or spindle is made to revolve by means of manual or any other power, the
difference in the sizes of the pulleys causes the cage to ascend or descend at will.
And by altering the relative sizes of the pulleys, the lifts may be made to raise or
lower light or heavy weights, thereby dispensing with geared wheels and forming
its own brake.
Dated this 17th day of September 1890
WILLIAM TROW.
COMPLETE SPECIFICATION.
Differential Self-sustaining Lifts.
WILLIAM TROW of No. 21 Chapman Road Small Heath, Birmingham, 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 consists of the improvements in lifts, hereinafter set forth, whereby
the usual "or any" brake power is dispensed with.
I will now proceed to describe with reference to the accompanying drawings the
manner in which my invention is constructed and used.
Figure 1 represents a front view of my improved "differential self-sustaining
lifts.
Figure 2 represents a side view of Figure 1.
Figure 3 represents a plan of Figure 1.
In carrying out my invention I provide a main lifting shaft or spindle 1 working
in bearings 2 such bearings 2 being supported on two or more brackets, plates or
bearers 3 such bearers being secured to the upper portion of guide posts 4 by means
of bolts or in any other suitable manner. To the main shaft 1 is connected a
hauling wheel 5 over the hauling wheel is passed an endless hauling rope 15 for
hand power use or in lieu of the hauling wheel 5 I, in some cases, prefer to use band
pulleys and friction wheels worked by steam power or other motive power.
On the main shaft 1 is also fixed a double angular grooved pulley 6 the diameter
of the grooves being of different dimensions and the angles of the grooves being of
the required obtuseness or acuteness to allow a rope to grip the groove without
slipping or the grooves may be recessed on the internal periphical face to receive
the links of a chain.
I provide an endless rope 7 or in lieu of the rope an endless chain the rope or

page_text: chain passing under a single pulley 8 such pulley 8 being secured to the top of
cage 9 as illustrated, thence over the angular pulley 6 thence over the two loose
pulleys 10 which are shewn revolving on the fixed spindle II secured to the top of
guide posts 4 thence down and under a pulley 12 secured to the top of balance
weight 13 so that when the shaft 1 is caused to revolve by means of manual power
or motive power of any kind applied to the hauling wheel 5 and endless rope 15 (or
their equivalent band pulleys and friction wheels) the difference in the periphical
dimensions of the two grooves formed on the pulley 6 will cause the cage 9 to ascend
or descend at will.
By altering the relative diameters or sizes of the pulleys 6 the lifts may be made
to raise or lower light or heavy weights.
The rope 7 working in the direction indicated by the arrows shews that the
quantity payed off by the smaller groove in pulley is less than the quantity taken
up by the larger groove in pulley 6 clearly demonstrates that the cage must rise.
The endless rope 7 pulling in an opposite direction on the groove in pulley 6 gives
the necessary sustaining power. To accelerate the speed of the lift a counter
shaft. 16 would be provided to which the hauling wheel, and endless rope 15 would
be attached by means of a spur wheel, working in conjunction with a pinion on a
shaft 1.
Having now particularly described and ascertained the nature of my said
invention and the manner in which the same is performed I declare that what I
claim is :
:
First The utilisation of an endless rope or chain passing over the arrange-
ment of pulleys illustrated and described in reference to Figures 1 2 and 3 for the
purpose of raising and lowering a cage.
Second-The countershaft hauling wheel and spur wheel gear as shewn dotted
in at Figure 2 for the purpose of accelerating or increasing the speed of lift cage.
Dated this Fifteenth day of June 1891.
WILLIAM TROW.