IMPROVEMENTS IN THE CONSTRUCTION OF HAND POWER LIFTS AND HOISTS
Year: 1884

page_text: 1 GEORGE ANDREWS, of 11 Walpole Street, New Cross, in the County of Kent,
Engineer, do hereby declare the nature of my Invention for "IMPROVEMENTS IN
THE CONSTRUCTION OF HAND POWER LIFTS AND HOISTS," to be as follows:-
The object of my invention is to provide an automatic brake to hand power lifts
and hoists, to obviate the necessity of applying a brake rope; which automatic
brake operates & prevents the descent of the cage, immediately the hand power
withdrawn.
is
The горе which sustains the cage, is caused automatically to put on the brake
band and make it grip the wheel, when such wheel is not being operated upon by
the hand power rope; but when hand power is applied thereto the brake is taken
off or eased and the wheel is free to revolve.
I form the brake wheel with teeth either centrally or on either side of the rim,
into which a pinion gears; or, in lieu of teeth, I make use of V or U grooves, for.
friction gear.
I mount such toothed or grooved pinion between two horizontal bars, which are
held below the brake wheel by a screwed rod fitted with adjusting nuts at each.
end of the brake band. The rods are made to slide in two guides bolted to the lift
frame. On the top of each guide is a steel spring or India rubber ring which keeps
the pinion in gear, when the lift is in motion.
When the hand rope is pulled down the pinion is driven by the brake wheel
against a distance stop on the horizontal bar, and the pinion is then free to turn;
but when the hand rope is released the pinion is driven towards the centre, which
tightens the brake band, and suspends the load.
Dated this 31st day of January 1884.
GEO. DOWNING,
Agent for Applicant.

page_text: ↑ GEORGE ANDREWS of 11 Walpole Street, New Cross, in the County of Kent,
Engineer, do hereby declare the nature of my said Invention for "IMPROVEMENTS
IN THE CONSTRUCTION OF HAND POWER LIFTS AND HOISTS," 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 my invention is to provide an automatic brake to hand power lifts
and hoists, to obviate the necessity of applying a brake rope; which automatic
brake operates and prevents the descent of the cage, immediately the hand power
is withdrawn, thus rendering the same self-sustaining.
The rope which sustains the cage, is caused automatically to put on the brake
band and make it grip the wheel, when such wheel is not being operated upon by
the hand power rope; but when hand power is applied thereto the brake is taken
off or eased and the wheel is free to revolve.
I sometimes form the brake wheel with teeth either centrally or on either side of
the rim, into which one or more pinions gear; but ordinarily, in lieu of teeth and
pinions, I make use of V or U grooves and rollers.
I mount such toothed pinions or rollers in a horizontal or curved guide, which is
placed below the brake wheel adjustable by means of a rod fitted with adjusting
nuts at the end of the brake band.
When the hand rope is pulled the rollers are driven by the brake wheel against
a distance stop on the horizontal bars, and the wheel is then free to turn; but
when the band rope is released the rollers are driven towards the centre, which has
the effect of tightening the brake band, and suspending the load.
The guides and rollers are sometimes made double acting to travel on each side
of the centre, in order that it may operate in either direction; the horizontal bar
being curved at each end, and I use balls instead of pinions or rollers working in
U grooves.
And in order that my said invention may be clearly understood, reference is
hereby made to the accompanying drawings, in which similar letters of reference
indicate corresponding parts.
Fig. 1 is a front elevation of a lift fitted in accordance with my said invention.
Fig. 2 is a side view of the same. Fig. 3 is a front view of a modification for light
loads, and Fig. 4 is a side view of the same. a is a bell crauk lever having a forked
end b, which carries two or more friction rollers cd, working in one or more
V grooves on the edge of the brake wheel e, the balance weight f presses the
friction roller or rollers into the grooves of the brake wheel, the large roller c
travels on the curved horizontal bar g, which is connected to the brake band h at
each end, one end by a joint i and the other end having an adjustable screw and
nuts j with a steel spiral spring which supports the weight of the brake band.
The small roller d travels in the groove as shewn at the end of the lever g. The
large roller c sustains, the load, by putting on the brake band h which grips the
wheel e.
When the rope m for raising the load is let go the large roller c runs in
toward the centre and tightens the band h by pressing on the top of the lever g
whereby the load is sustained.
.
In order to lower the load, the hand rope m¹ on the opposite side is pulled, the
emall roller d is thereby driven towards the centre, on the incline of the slot,
which partly releases the grip on the brake band, and which allows the load to
descend slowly. In order to lower quickly the line k attached to the brake lever a
is pulled, whereby the brake lever a is raised; this releases the friction rollers, and

page_text: allows of a rapid descent, which can be immediately stopped by simply letting go
of the rope k. n is the load or cage for the gooils.
The above arrangement is also applicable to chain and rope blocks.
In Figs. 3 and 4 o is a link which supports the centre p of the combined brake
wheel and pulley e. The lever a, loaded with the weight f, carries a modified form
of T head, the upper end of which carries the friction roller c, and the lower end a¹
of which lever is a slotted link in which the pin a' works. This pin is attached
to the lower end of an inner frame q. At the top of this inner frame o̟ the block r
is fitted to act as a brake.
When the cord k (Fig. 3) is pulled upwards, the roller c is withdrawn from
contact with the groove in e; the frame q is raised by the fixed pin a* actuated by
the slot al; the block is consequently raised off the cord and out of the groove,
and the load is then free to descend; the speed of which descent may be checked
or entirely arrested by simply letting go of the cord k.
When the load n is being raised the pulley e pushes the roller c aside, and
thereby eases the pressure which would otherwise arise from the operation of o
and .
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 The application of automatic brakes to hand power lifts and hoists, constructed,
arranged, and operating substantially as and for the purposes herein before described
and shewn on the drawings Figs. 1, 2, 3 and 4.
2 The application to hand power self-sustaining lifts and hoists, of the weighted
lever and self-acting rollers taking into grooves in the brake wheel or pulley, in
combination with the strap h or block r, substantially as and for the purposes
herein before described and shewn on the drawings Figa, 1, 2, 3 and 4.
3 The combination and arrangement of the several and respective parts, together
forming my improvements in the construction of band power lifts and hoists,
substantially as and for the purposes herein before described and shewn on the
drawings.
Dated this 31st day of October 1884.
GEO. DOWNING.
Agent for Applicant.