IMPROVEMENTS IN HOISTING AND STEERING GEAR
Year: 1884

page_text: I ALEXANDER MELVILLE CLARK of the firm of A. M. and Wm. Clark of
53 Chancery Lane in the County of Middlesex, Fellow of the Institute of Patent
Agents do hereby declare the nature of the invention for IMPROVEMENTS IN
HOISTING AND STEERING GEAR and in what manner the same is to be performed,
to be particularly described and ascertained in and by the following statement :-
This Invention relates to certain new and useful, improvements in that class of
hoisting and steering machines in which the drum around which the operating
chain or cable is passed is operated by a hand rope or chain or by a crank.
The object of the invention is to reduce the friction of the working parts and to
provide a brake device which locks the machine in any desired position and
prevents the load from descending when the land rope or chain or the crank is
released.
In the accompanying drawings. Figure 1 is a cross sectional view of my
improved hoisting and steering machine. Figure 2 is a longitudinal sectional view
on the line xx figure 1 in the direction of the arrow w¹. Figure 3 is a longitudinal
sectional view on the line xx figure 1 in the direction of the arrow v. Figure
is a plan view, parts being, shown in section. Figure 5 is an inside elevation of
the brake mechanism.
The shaft A is journaled in the lower ends of the shanks of a frame B which is
U shaped or of any other suitable construction and is provided at its top with a
hook C for hanging it.
One end of the said shaft A projects from the frame B, and on the said projecting
end of the shaft the wheel D is rigidly mounted over which the endless hand
chain E or hand rope passes. The rim of the wheel D can be grooved or the rim
is provided with forks or projections on which the hand chain or rope can catch.
On the shaft A two cams or projections F F are rigidly mounted in two parallel
adjoining planes, the cams projecting in diametrically opposite directions.
A shaft G is journaled in the frame B above and parallel with the shaft A on
which shaft Ga wheel H is rigidly mounted which is provided in its rim with two
rows of recesses h h¹ of such size as to receive the cams F F¹ the two rows of
recesses being in parallel planes and so arranged that their centres will alternate;
that is the projection formed between two recesses h will be opposite the middle of
one of the recesses h¹ and so on as.shown in figures 3 and 4..

page_text: !
A grooved toothed or sprocket wheel or hub J is loosely mounted on the shaft G
over which wheel the lifting chain K passes. The wheel J is provided with an
arm L on the free end of which an aperture L is formed into which a strong pin M
passes, which projects from a ring N provided with an eccentric inner opening
which ring is held loosely in a circular casing O formed on the inner surface of one
of the shanks of the frame. B.
In the opening of the ring N a ring P having an eccentric opening is held
loosely, in which an eccentric disc I is held, which is mounted loosely on a neck of
the casing O, and from which disc I a strong pin Q projects at a point diametrically
opposite the pin M.
On the shaft G a cross piece R is rigidly mounted which is provided with a long
part R and a short part R2 the long part R¹ having a segmental slot r¹ in its
end and the short part R2 having a segmental slot in its end (see figure 2) The
long part R' is held between the ring. N and the arm' L, and the pin M passes
through the slot 1 and the pin Q passes through the slot ...
The ring P is provided with two diametrically opposite slots S through which
studs T pass, which project from a ring U held eccentrically to the shaft G in the
casing O.
Midway between the two studs T studs W are formed on the opposite surface of
the ring the said studs W passing through vertical slots V in the casing O.
The diameter uniting the studs T and the diameter uniting the studs W cross
each other at right angles.
The operation is as follows:
If the wheel D is revolved in the direction of the arrow 61 by means of the hand
chain or rope, the cams F F alternately passing into the recesses h h¹ revolve
the shaft G and the cross piece R mounted on the same, in the direction of the
arrow a¹.
The end piece at the slot 1 acting on the pin M turns the ring N and the arm Li
in the direction of the arrow a¹ thereby raising that part of the lifting chain from
which the weight is suspended.
The several parts which are few in number can be made very heavy strong and
durable, and a very great leverage and much power is obtained.
As long as the cross piece R revolves the ring N in the direction of the arrow a'
the short part R2 will revolve the disc I in the same direction and the parts will
not bind but revolve freely the rings P and U moving up and down laterally.
If the hand chain or rope is released the weight on the lifting chain will revolve
the hub or wheel J in the inverse direction of the arrow al and will move the
pin M and the ring N in the like direction. But as this movement does not come
from the shaft G, the eccentric disc I will not be revolved and the ring P will not
be moved laterally and thus the ring N will be jammed and wedged in between
the rim of the casing O and the ring P which is temporarily fixed, thus locking
the several parts in place.
If the shaft G is revolved the apparatus can be worked in either direction and
will not bind, but as soon as the weight of the load acts on the mechanism the
parts will bind in the manner described and act as a brake.
1
It will be observed that the narrow parts and likewise the wide parts of the
ring N and the disc I will always be at opposite sides of the shaft G.
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 combination with the wheel H having two parallel rows of recesses h h¹
in its rim and mounted on the shaft G, of the cams F F on the parallel shaft A,
the chain pulley or wheel J mounted loosely on the shaft G, and means for
revolving the chain pulley or wheel J with the shaft G substantially as herein
shown and described.
2nd The combination with the wheel H having two rows of recesses h h¹ and
mounted on the shaft G, of the cams F, F1, mounted on the shaft A and adapted to

page_text: pass into the notches h¹, the chain pulley J mounted loosely on the shaft G and
provided with an arm L, the cross piece R. mounted rigidly on the shaft G, and of
means for connecting the arm L and the cross piece R so that the pulley J will be
revolved from the shaft G, substantially as herein shown and described.
3rd In a brake for steering or hoisting gear, the combination with the eccentric
disc I of the eccentric ring N, the ring P between the ring N and disc I, and of
means for revolving them both in the same direction from the shaft carrying the
lifting chain pulley, substantially as herein shown and described.
4th In a brake for steering or hoisting gear, the combination with the eccentric
disc I, the eccentric ring N, and the ring P between them, of the arm R mounted
rigidly on the shaft G and provided with a segmental slot in each end, pins M
and projecting from the ring N, and disc I through the slots in the ends of the
cross piece R, and of a pulley for the hoisting chain which pulley is revolved by
the pin M, substantially as herein shown and described.
5th In a brake for hoisting or steering gear, the combination with the eccentric
disc I the eccentric ring N, and the ring P held between them and provided with
the diametrically opposite slots S, of the casing O having the diametrically opposite
slots V, the ring U held in the casing O and provided with the studs T and W
projecting through the slots S and V, the cross piece R mounted rigidly on the
shaft G and provided with segmental slots in the opposite ends, the pins M and Q
projecting from the ring N and the disc I through the slots in the ends of the cross
piece R, and the lifting chain pulley J mounted loosely on the shaft G and adapted
to be revolved by the pin M, substantially as herein shown and described.
Dated this Qord day of Falm 1881.