Improvements in or relating to Lifting Tackles
Year: 1894

page_text: Date of Application, 13th Dec., 1894-Accepted, 16th Feb., 1895
COMPLETE SPECIFICATION.
Improvements in or relating to Lifting Tackles,
A communication from CHARLES FOCCROULLE, Mechanical Engineer, of
Zinkempois-Angleur, near Liege, in the Kingdom of Belgium.
.
I, ALFRED JULIUS BOULT of 323 High Holborn in the County of Middlesex,
Chartered Patent Agent, 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 :-
In the drawings illustrating this improved tackle :-
Figure 1 is a longitudinal section through the coned nuts and ratchet wheels
showing the pawls and spindle bearings.
Figures, 2, 3, 4, 5 and 6 are transverse sections through the coned nuts and screw
threaded spindle.
Figure 7 is a side elevation partly in section showing the complete tackle.
Figure 8 is an end elevation also partly in section of the tackle, certain parts not
being shown.
Figure 8ª is an elevation of one of the pawls and ratchet wheels.
Figure 9 is section on the line 1-1 of Figure 7.
Like letters indicate like parts throughout the drawings.
The constituent elements of this tackle are:-
1. A forged nut Q (Figures 7 and 9) having six or eight sockets or cells,
offering in plan the sides 2, 4, 6, 8 and in section the sides 1, 3, 5, 7 and specially
designed to engage with six or eight chain links:
2. Two frames L and M1 (Figures 7, 8, 9) whereof the arms are sufficiently
prolonged to allow of the free rotation of the wheels and receive the stay-guide
supports.
3. Two stay-guide-supports N' and O (Figures 7, 8 and 9) staying the two
frames L and M' guiding the chain-links S in the sockets 1, 2, 3, 4, 5, 6, 7, 8, of the
nut Q, and supporting the two suspension hooks T of the chain.
4. A jointed shaft A' D' having two conical parts A and D (Figure 1)
a threaded spindle B two ratchets C and E and two pins H and I provided with
special eyes, automatically combining by the load to form a double safety-brake,
applicable in fact to all shafts for the transmission of power.
WORKING.
On pulling the hand-chain in the proper direction the fly-wheel R works the
wheels R R and nut Q gearing with the lifting chain; and in the forward
movement, the pin I (Figure 1) advances against the angles M of the spindle B
(Figure 2) and carry it against the pin H (Figure 3) which in its turn imparts
movement to the conical nut or motor-shaft D. This simple movement, obtained
by means of the two special eyes pierced in the spindle B to receive the pins H
and I compresses the cones A and D with reciprocal pressure aroinst the ratchet-

page_text: in the opposite direction to that of lifting. The pin I falls back and at once comes
against the opposite angles N N of the spindle B (Figure 4) and carries it against
the pin H (Figure 5); and this simple movement of recoil obtained through
the same pin-arrangement or device above-mentioned, suffices to relax and
re-establish the jointed shaft and permits of its free rotation backwards, so long
only as the return or lowering motion of the fly-wheel continues, for as soon as that
ccases the load acts upon the section D and remains suspended and stationary
through its own weight, thus reproducing by the approach to each other of the two
cones the counter-pressure reciprocally of the two ratchet-wheels engaging
with F G and therefore the instantaneous double-safety brake.
It is of material importance to note:-
1. That the two pins with special eyes are essential to the present jointed shaft,
not only to produce the communicated motion, but also to limit the double recoil
properly, because without these two special eyes, the two cones would be unable to
move or work in any way. On the other hand, were these two pins absent, the two-
cones would recoil, as soon as the motion of the fly-wheel was reversed with such
force as to press against the bearings J K in such manner that the action of the
brake would become impossible.
2. That this jointed shaft really ensures double the safety given by single-acting
brakes, which have only a single pawl and ratchet wheel as this has two,
independent the one of the other. Hence a double safety; for if one ratchet and
pawl went wrong, the brake would nevertheless act perfectly.
Having now particularly described and ascertained the nature of this said inven-
tion as communicated to me by my foreign correspondent and in what manner the
same is to be performed, I declare that what I claim is :-
1. A lifting tackle with nut frames stays and shaft substantially as described and
illustrated in the accompanying drawings.
2. In a lifting tackle the combination of a nut such as Q frames stays coned
pieces such as A and D screw spindle such as B pins such as H and I ratchet
wheels such as C and E with pawls G and F substantially as described and
illustrated in the accompanying drawings.
3. In a lifting tackle the combination of a driving shaft having an externally
coned hollow end a coaxial shaft with similar coned end a screwed spindle engaging
with internal threads in and also provided with slack pin connections with both the
said shaft ends a double ratchet wheel tapered to fit these ends and ratchets engaging
with this wheel substantially as described.
4. The combination and arrangement of parts constituting the complete lifting
tackle substantially as described and illustrated in the accompanying drawings.
Dated this 13th day of December 1894.
BOULT & WADE,
Agents for the Applicant.