An Improved Mode or System of Arranging and Operating Self-sustaining Hand Hoists.
Year: 1896

page_text: Date of Application, 24th July, 1896
Complete Specification Left, 24th Apr., 1897-Accepted, 19th June, 1897
PROVISIONAL SPECIFICATION.
An Improved Mode or System of Arranging and Operating
Self-sustaining Hand Hoists.
I, ROBERT MIDDLETON, of Sheepscar Foundry, Leeds, in the County of York,
Engineer, do hereby declare the nature of this invention to be as follows:-
The invention has reference to a mode or system of arranging and operating hand
hoists and making them self-sustaining under all circumstances.
The object of the invention is to arrange a hoist so that its maximum load may be
raised as easily as the average load in an ordinary hoist; its load, light or heavy,
being also self-sustaining.
I accomplish my object as follows:-First I overbalance the hoist about 50 per cent.
i.e. if the maximum weight to be lifted be four cwts., I arrange a counter-weight of
say two cwts., to about half balance the maximum gross load. Suppose now, for
example, a half load (two ewts.) be lifted, then the gross load and the balance weight
If,
would equalise one another, and render a self-sustaining gear of little or no use.
however, a load lighter than one half (say one cwt.) be lifted, then, on ceasing to
lift, the balance weight would require to be self sustained; whereas, on the contrary,
when the load lifted is greater than half load (say three cwts.) such load would
require to be self-sustained. To meet this double duty I arrange a duplex sustaining
gear, one portion of which sustains the load, whilst the other, in turn, sustains the
balance weight.
A mode of arranging such a duplex gear is as follows:-On the shaft of, and at
each side of, the load-bearing wheel, or its pinion or other equivalent, I arrange
suitable pawls and pawl wheels, one acting in one direction and one in the other.
The boss of the loaded wheel is suitably screwed, and is mounted on a correspondingly
screwed portion of the shaft, the pawl wheels on each side nearly touching it. On
the outer side of each pawl wheel is a thrust collar (mounted on the said shaft)
between which, and the loaded wheel, the pawl wheel (to the right or left as the case
may be gets tightly nipped whenever the loaded wheel, or its equivalent, screws
itself, by way of relief, along the shaft against such pawl wheel.
The thrust bearing collars may carry friction pieces or brakes to compel the pawls
to fall into, or release, the teeth of their wheels, without fear of a mishap, whenever
the actuating power changes from side to side of the shaft, be that through a wheel
or otherwise.
The pith of the invention lies (combinedly) firstly, in the overloading, as it were,
of the balance weight, and secondly, in the arrangement of a duplex sustaining gear,
one portion of such gear being arranged to sustain the load, and the other to sustain
the balance weight.
From what has been explained, it must be understood that variations in the type
of the duplex sustaining gear, or in its details, may be arranged and introduced,
without departing from the spirit of the invention.
The balance weight may be built up in different pieces, so that when a prolonged
series of light lifts is to be made, a less balance weight than one half the maximum
may be brought into use.

page_text: An Improved Mode or System of Arranging and Operating
Self-sustaining Hand Hoists.
I, ROBERT MIDDLETON, of Sheepscar Foundry, Leeds, in the County of York,
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 :-
The invention has reference to a mode or system of arranging and operating hand
hoists, and to appliances for making them self-sustaining unler all circumstances.
The object of the invention is to arrange a hoist so that its maximum load may be
raised as easily as the average load in an ordinary hoist; its load, light or heavy,
being also self-sustaining.
In order to fully describe my invention I have annexed three drawings which set
out a geared hoist arranged in accordance with my system.
Fig. 1 is a diagrammatic arrangement of my system of loading and counter-
balancing, shown in elevation, whilst Fig. 2 shows the corresponding end view.
Fig. 3 is a plan showing in detail the various parts which complete the invention.
Fig. 4 is a sectional elevation which will assist in explaining the details of one half
of the self-sustaining gear, whilst Fig. 5 explains the other half.
Unimportant portions of these figures are curtailed in order to show the remainder
on an enlarged scale.
The same letters refer to the same parts in all the figures.
I accomplish my object as follows:-
First I overbalance the hoist about 50 per cent., i.e. if the maximum weight to be
lifted be 4 cwts., I arrange a counterweight of some 2 cwts., to about half balance
the maximum gross load. Suppose now, for example, a half load (2 cwts.) be lifted
or lowered, then this load on the one side, and the balance weight (2 ewts.) on the
other, would equalise one another and render a self-sustaining gear of little or no use.
If, however, a weight lighter than a half load (say 1 cwt.) be lifted or lowered, then,
on ceasing action, the balance weight would require to be self-sustaining; whereas,
on the contrary, should the weight moved be greater than a half load (say 3 cwts.)
such load would require to be self-sustaining.
In Fig. 1, A is the cage supposed to be arranged with a gross load of 4 cwts. and
with a balance weight, B, of approximately 2 cwts, as before mentioned; C is the
actuating wheel, mounted on the shaft C, with rope C; whilst D is the actuating
pinion which gears into the lifting wheel mounted on the same shaft, D2, as the
lifting pulley E over which the rope or chain sustaining the cage A and the balance
weight B is hung.
To meet the double duty of sustaining either the cage or the balance weight (which
ever happens to be the heavier) I arrange a duplex sustaining gear, one portion of
which sustains the load whilst the other in turn sustains the balance weight."
A mode of arranging such a duplex gear is as follows, continuing with the
example of a geared hoist as shown in Figs. I and 2 :-
On the shaft C, and on each side of the actuating pinion D, I arrange suitable
pawls and F, and pawl wheels G and G', one acting in one direction and one in
the other, as shown in Figs. 4 and 5. The boss of the pinion D is suitably screwed,
in this case with a right hand thread, and is mounted on a correspondingly screwed
portion of the shaft, the pawl wheels (or their bosses) on each side nearly touching
it. On the outer side of each pawl wheel are thrust collars H and H' (mounted on,
and preferably sunk into, the said shaft), between which and the loaded pinion, the

page_text: pawl wheel (to the right or left as the case may be) gets tightly nipped whenever
the pinion (or its equivalent) screws itself, by way of relief, along the shaft against
such pawl wheel.
The thrust-bearing collars may carry or support friction pieces or brakes J and J'
to compel the pawls to fall into, or release, the teeth of their wheels, without fear of
a mishap, whenever the actuating power changes from side to side of the shaft, be
that through a pinion, as shown, or otherwise, as in the case of a simple ungeared
hoist. Figs. 4 and 5 show these friction pieces J and J very clearly; these are
made to clip sheaves K and K' keyed on the shaft C, and being differently connected
to the different class of ratchet pawls F and F by the links L and L' respectively,
it follows that they draw in, or throw out, their respective pawls in accordance with
the direction of rotation of the shaft C. Stops M and M' mounted on the
brackets N and N' prevent any undue rotation of the friction pieces. The ratchet
pawls are mounted on a cross stay O uniting the two side frames, P and P, of the
apparatus, and from this same stay the brackets N and Ni for the stops M and M', are
suspended. The pawls as here arranged differ from each other, one being pointed
and the other being hooked, so as to receive a push and pull from the teeth of their
respective ratchet wheels. The two side frames P and P', united by the cross stay O,
are shown bearing the brackets Q and Q for the pinion shaft C', and are further
arranged to take the main shaft D².
A further outer bearing for the outer end of the shaft D3 may also be arranged
as shown at R.
The load-bearing wheel E may be made to receive and sustain a chain where such
is preferable to a rope.
The pith of the invention lies (combinedly) firstly, in the overloading, as it were, of
the balance weight, and secondly, in the arrangement of a duplex sustaining gear,
one portion of such gear being arranged to sustain the load, and the other to sustain
the balance weight.
From what has been explained it must be understood that variations may be
arranged in the apparatus, which may be simple or geared, and in the type of the
duplex sustaining gear, or in its details, without departing from the spirit of the
invention.
The balance weight may be built up in different pieces, so that when a prolonged
series of light lifts is to be made, a less balance weight than one half the inaximum
may be brought into use.
The term cage "must be understood to embrace any weight lifting appliance
from a simple hook upwards, and such "cage" may be hung on a chain running
over a suitable sprocket or sprocket wheel, which, in a simple hoist, would take the
place of the actuating pinion D, sustaining itself against the pawl wheel on either
side, according to the overbalance or otherwise of the load then on the "cage."
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 :-
1. The improved mode or system of overbalancing, arranging, and operating
self-sustaining hand hoists, in and after the manner described and shown herein, with
the object and for the purpose set forth.
2. The combination of a duplex sustaining gear with an arrangement of hoist
fitted with a weight lifting appliance and an overbalanced counterweight, substantially
as described and shown, with the object and for the purpose set forth.
3. The combined duplex self-sustaining gears working with a pinion (or its
equivalent) D mounted on a screwed portion of its shaft so as to engage one or
other portion of the said sustaining gears, substantially as described and shown, with
the object and for the purpose set forth.
4. The combination of the pinion, or its equivalent, D, the ratchet wheels G and G¹,
the pawls F and F', the friction pieces J and J and their connections, and the
thrust receiving pieces H and H', working in further combination with an

page_text: overbalanced hoisting gear, substantially as described and shown, with the object
and for the purpose set forth.
92-1 der of Anril 1807
WM. SNOWDON,
Box W.S., 24, Basinghall Street, Leeds, Agent for the Applicant.