IMPROVEMENTS IN LIFTS OR HOISTS
Year: 1879

page_text: LETTERS PATENT to David Edwards, of Cardiff, in the County of Glamorgan,
Carpenter, and Thomas Alexander, of Cardiff aforesaid, Carpenter, for the
Invention of "IMPROVEMENTS IN LIFTS OR HOISTS."
Sealed the 11th July 1879, and dated the 27th March 1879.
PROVISIONAL SPECIFICATION left by the said David Edwards and Thomas
Alexander at the Office of the Commissioners of Patents on the 27th March
1879.
DAVID EDWARDS, of Cardiff, in the County of Glamorgan,' Carpenter, and
THOMAS ALEXANDER, of Cardiff aforesaid, Carpenter. "IMPROVEMENTS IN LIFTS
OB HOISTS."
Our Invention has reference to lifts or hoists used for lifting or hoisting and
lowering heavy bodies in warehouses, hotes, and other places; and our said Inven-
tion consists in constructing and arranging the parts of the said lifts or hoists in
the manner hereinafter described.
To one end of a horizontal shaft or axis working in fixed bearings a pulley is
fixed; over this pulley an endless chain or rope is passed, by drawing down one or
other side of which endless chain or rope motion in one or other direction is given
to the pulley and shaft. The pulley end of the shaft works directly in its bearing,
but the other end of the shaft takes into a sleeve or tubular collar, a contracted
part of which constitutes the neck at that end of the shaft which works in the
other bearing. Thus the end of the shaft carrying the pulley can both rotate and
slide while the sleeve constituting the other end can rotate, but cannot slide in its
bearing. The interior of the said neck of the sleeve has a quick threaded concave
screw formed in it, and the part of the shaft fitting in the said sleeve has a
corresponding quick threaded convex screw, the said sleeve and screwed end of the
shaft constituting a screw box and screw engaged with one another. When
the shaft is turned in a direction proper to drive home a screw, the sleeve being
at the same time stationary, the screw advances in the sleeve, the neck of the
shaft at the pulley end permitting as already explained of a sliding motion in the
shaft. The chain or cord by which the weight or article is raised or lowered is
attached to a drum working freely on the shaft. This drum carries at each end a
disc, the disc at the end of the drum most distant from the pulley end of the shaft
being larger than the other. The face of this large disc is opposed to the face of a
disc of the same size carried by the sleeve, and when the larger drum disc is pressed
against the sleeve disc by the means hereinafter described, the frictional contract
กา

page_text: of the two causes them to rotate together. The pressure of the larger drum disc
against the disc on the sleeve, by which pressure the requisite frictional contact
between the two discs necessary to make the drum rotate with the shaft when the
latter turns in a direction proper to raise the drum chain is produced as follows:
The screw end of the shaft terminates in a cylindrical rod having a fine screw at
its end; fitted in a screw nut sliding upon the rod described is a strong metallic disc.
This disc fits loosely in a cylindrical box which forms the expanded termination of
the sleeve.
+
In this box is a thick disc or short cylinder of india rubber through a hole in the
middle of which the rod terminating the axis passes. By screwing up the nut on
the rod more or less the india rubber can be compressed more or less between the
metallic disc on the rod and the bottom of the box terminating the sleeve. The
compressed india rubber reacting on the metallic disc and through it on the shaft
draws the shaft into the sleeve by a screwing motion. The pulley end of the shalf
has a collar pinned to it, and when the shalf advances as described the said collar
advancing with it presses the large drum disc against the disc on the sleeve, and
produces the required friction between the said discs to cause the drum to rotate
with the shaft. By screwing the screw nut to a greater or less distance on the end
of the rod terminating the screw end of the shaft, the pressure upon the india
rubber can be regulated so as to produce a greater or less amount of friction
discs. The drum disc has an annular rib or projection on its face.
between the into a corresponding depression in the sleeve disc. The two discs have
which takes
thereby a firmer hold on one another.
In addition to the drum and its discs working loosely upon the shaft, and the
collar pinned to the shaft, the said shaft carries another small disc opposed to the
small disc on the drum. This small disc has a pad or cushion of india rubber let
into its face, by which, when pressed against the small disc on the drum it is made
to bind the more tightly against it. This small loose disc is situated on the shaft
between the drum, and the collar pinned to the shaft. Both the sleeve and the
last described loose disc are provided with ratched wheels. Pawls engaging in the
said ratched wheels prevent the rotation of the sleeve and the loose disc excepting
in the direction proper to raise the drum chain. When the parts are in the normal
positions and the endless rope over the pulley is drawn down on the side proper
for raising the pulley chain, the pulley, the shaft, and all the parts carried by it
rotate together, and when the endless rope is loosed the body being raised remains
safely suspended at any height to which it may have been brought, the ratchet
wheels and pawls preventing the backward rotation of the shaft.
When it is wished to lower the drum chain the endless rope on the pulley is drawn
down on the side opposite to that by which the raising motion is produced so as to
give the shaft a backward motion. As the sleeve is prevented by its ratchet wheel
and pawl from rotating in a backward direction the screw of the shaft rotates in the
screw box in the sleeve, and the shaft performs a retiring sliding motion, thereby
relaxing the pressure by which the larger drum disc was held against the sleeve
disc, and allowing the drum to perform a backward or unwinding motion. The
small loose disc produces by the elastic pad in its face such an amount of friction
as suffices to regulate the backward motion of the drum and the descending motion
of the chain.
Immediately the endless rope over the pulley is liberated the shaft by the
expansion of the india rubber at its screwed end is drawn into the sleeve, the
drum is again gripped and the apparatus ready again for raising the drum chain.
Instead of producing the requisite pressure of the friction discs upon one another
by the action of a screw as described, the same effect may be produced by means
of a cam, or eccentric, or inclined plane, or by parallel links, or eccentric wheels or
rollers acted upon by springs, volute, conical, or spiral worm, laminated india
rubber, or other equivalent means.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
'the said David Edwards and Thomas Alexander in the Great Seal Patent
Office on the 17th September 1879.
DAVID EDWARDS, of Cardiff, in the County of Glamorgan, Carpenter, and
THOMAS ALEXANDER, of Cardiff aforesaid, Carpenter. "IMPROVEMENTS IN LIFTS
OR HOISTS."
Our Invention has reference to lifts or hoists used for lifting or hoisting and
lowering heavy bodies in warehouses, hotels, and other places; and our said Inven-
tion consists in constructing and arranging the parts of the said lifts or hoists in
the manner herein after described.
To one end of a horizontal shaft or axis working in fixed bearings a pulley is
fixed; over this pulley an endless chain or rope is passed, by drawing down one or
other side of which endless chain or rope motion in one or other direction is given
to the pulley and shaft. The pulley end of the shaft works directly in its bearing,
but the other end of the shaft takes into a sleeve or tubular collar, a contracted
part of which constitutes the neck at that end of the shaft which works in the
other bearing. Thus the end of the shaft carrying the pulley can both rotate and
slide while the sleeve constituting the other end can rotate but cannot slide in its
bearing. The interior of the said neck of the sleeve has a quick threaded concave
screw formed in it, and the part of the shaft fitting in the said sleeve has a cor-
responding quick threaded convex screw, the said sleeve and screwed end of the shaft
constituting a screw box and screw engaged with one another. When the shaft is
turned in a direction proper to drive home a screw, the sleeve being at the same
time stationary, the screw advances in the sleeve, the neck of the shaft at the
pulley end permitting, as already explained, of a sliding motion in the shaft. The
chain or cord by which the weight or article is raised or lowered is attached to a
drum working freely on the shaft. This drum carries at each end a disc, the diso
at the end of the drum most distant from the pulley end of the shaft being larger
than the other. The face of this large disc is opposed to the face of a disc of the
same size carried by the sleeve, and when the larger drum disc is pressed against
the sleeve disc (by the means herein after described) the frictional contact of the
two causes them to rotate together. The pressure of the larger drum disc against
the disc on the sleeve, by which pressure the requisite frictional contact between
the two discs necessary to make the drum rotate with the shaft when the latter
turns in a direction proper to raise the drum chain is produced as follows:-The
screw end of the shaft terminates in a reduced part having a fine screw at its end
fitted in a screw nut. Sliding upon the screwed reduced part described is a strong
metallic disc; this disc fits loosely in a cylindrical box which forms the expanded
termination of the sleeve.
In this box is a thick disc or short cylinder of india rubber through a hole in the
middle of which the end of the axis passes. By screwing up the nut on the
reduced screw of the axis more or less the india rubber can be compressed,
more or less, between the metallic disc on the said axis and the bottom of the
box terminating the sleeve. The compressed india rubber reacting on the
metallic disc, and through it on the shaft, draws the shaft. into the sleeve by
a screwing motion. The pulley end of the shaft has a collar pinned to it, and
when the shaft advances, as described, the said collar advancing with it presses
the large drum disc against the disc on the sleeve and produces the required friction
between the said discs to cause the drum to rotate with the shaft.
By screwing the screw nut to a greater or less distance on the screwed end of the
shaft the pressure upon the india rubber can be regulated so as to produce a greater
or less amount of friction between the discs. The drum disc has an annular rib or
projection on its face which takes into a corresponding depression in the sleeve disc.
The two discs have thereby a firmer hold on one another.

page_text: In addition to the drum and its discs working loosely upon the shaft, and the
collar pinned to the shaft, the said shaft carries another small disc opposed to the
small disc on the drum. This small disc has a pad or cushion of india rubber let
into its face by which when pressed against the small disc on the drum it is made
to bind the more tightly against it. This small loose disc is situated on the shaft
between the drum and the collar pinned to the shaft. Both the sleeve and the last
described loose disc are provided with ratchet wheels. Pawls engaging in the said
ratchet wheels prevent the rotation of the sleeve and the loose disc excepting in the
direction proper to raise the drum chain.
When the parts are in their normal positions and the endless rope over the pulley
is drawn down on the side proper for raising the pulley chain, the pulley, the shaft,
and all the parts carried by it rotate together, and when the endless rope is loosed,
the body being raised, remains safely suspended at any height to which it may have
been brought, the ratchet wheels and pawls preventing the backward rotation of
the shaft.
When it is wished to lower the drum chain the endless rope on the pulley is
drawn down on the side opposite to that by which the raising motion is produced
so as to give the shaft a backward motion. As the sleeve is prevented by its
ratchet wheel and pawl from rotating in a backward direction the screw of the shaft
rotates in the screw box in the sleeve and the shaft performs a retiring sliding
motion, thereby relaxing the pressure by which the larger drum disc was held
against the sleeve disc and allowing the drum to perform a backward or unwinding
mction. The small loose disc produces by the elastic pad in its face such an amount
of friction as suffices to regulate the backward motion of the drum and the descending
motion of the chain.
Immediately the endless rope over the pulley is liberated the shaft by the expan-
sion of the india rubber at its screwed end is drawn into the sleeve, the drum is
again gripped, and the apparatus ready again for raising the drum chain.
We will now proceed to describe with reference to the accompanying Drawings
the manner in which our Invention may be performed.
Figure 1 represents, partly in horizontal section and partly in plan, a hand worked
lift or hoist suitable for warehouses, hotels, and the like, where a heavy load is to be
raised and lowered, the parts of the said lift or hoist being constructed, arranged,
and worked according to our Invention; Figure 2 represents part of the pawl
mechanism of the lift partly in side elevation and partly in section; Figure 3
represents an arrangement of reversing gear to be applied to the lift when worked
by steam power or power other than manual; Figure 4 represents in perspectivo
the principal parts of the lift shewn in Figures 1 and 2.
The same letters indicate the same parts in Figures 1, 2, 3, and 4.
a is the principal horizontal shaft or axis of the lift or hoist, and b is the counter
or parallel shaft geared to and receiving motion from the said shaft a. The shaft b
carries the sheave or pulley cover which the rope (or chain) of the cage or load to
be raised or lowered passes. The principal shaft a works in bearings at a², a³, a*,
fixed on the framing of the hoist, the said shaft a being capable of a limited sliding
motion in addition to a rotatory motion. On one end of the said shaft a is a pulley
or wheel d over which an endless rope (or chain) passes. By drawing down by
hand one or other side of this endless rope, motion is given in one or other direction
to the wheel d and shaft a. The end of the shaft a most distant from the pulley
end d does not work directly in its bearing at a', but works in a sleeve or tubular
collar e. The said sleeve or tubular collar e is capable only of a rotatory motion in
consequence of the contracted part of the said sleeve or collar engaging with the
bearing at a in the manner represented. By this arrangement the shaft a is
capable of both sliding and rotating, but the sleeve e, in which one end of the shaft
works, is capable only of rotating with the said shaft. To one end of the said
sleeve or collar e a cylindrical box or case e² open at one end is affixed, and the
opposite end of the said sleeve or collar e carries a friction disc e³ having an annular
bearing rib et. In the box or case e³ is a volute steel or other spring f, one end of

page_text: the said spring taking its abutment against the closed end of the box or case e³, and.
the other end of the spring taking its abutment against a sliding collar g on the
reduced screwed end as of the shaft a, the said collar g being adjusted and fixed on
the said end as of the shaft by the compressing nut h, and the latter being fixed by
the lock nut i and cotter k. By screwing the screw nut h more or less on the
screwed end as the pressure of the spring f may be regulated for the purpose herein
after explained. To the spring case e and forming a continuation of the sleeve e a
screw box is affixed in the manner represented in the Drawing. The disc e³,
sleeve e, case e³, and screw box 1, and the adjusting parts of the spring frotate with
the shaft a and constitute one half of a friction clutch driven by the said shaft.
The shaft a is provided at a with a quick threaded screw which works in the
screw box . When the shaft a is turned in one or other direction by the hand
wheel at d.the quick threaded screw as either advances in or retires from out the
screw box l, the sleeve e carrying the said screw box being stationary, and the
shaft a has thereby a sliding motion given to it to couple the disc e' with or
uncouple it from the drum m. The drum m works loosely on the shaft a and
carries at one end a large disc m³ having an annular depression in it which can be
made to take upon the annular rib e* of the sleeve disc e³, and by frictional contact
cause the two discs m³ and es to rotate together. The other end of the drum m
carries a smaller disc m³. Working loosely on the shaft a is another disc n, and
between the two discs m³ and n is an india rubber pad, or cushion, or spring p for
binding the two discs tightly together. A friction washer at q is interposed
between the pad, or cushion, or spring p and the drum disc m³; r is a collar pinned
to the shaft a. On the drum m is a pinion s which gears with a spur or toothed
wheelt on the counter shaft b so as to gear the two shafts a and b together. On
the collar of the loose disc n is a ratchet wheel u with which the pawl u³ carried by
and working on the counter shaft b gears for preventing the back motion of the
said disc n, and on the sleeve e is a ratchet wheel us with which a second pawl u
on the said countershaft gears for preventing the back motion of the said sleeve and
the shaft a. The construction of the pawls us, ut, is hereinafter described.
By an examination of Figure 1 of the Drawings it will be seen that by the
screwing up of the nut h on the screwed end a* of the shaft a the volute (or other)
spring situated between the collar g and closed end of the box e on the sleeve is
compressed, and the said compressed spring reacting on the collar g and through it
on the shaft a draws the said shaft a into the screw box / by a screwing motion,
the sleeve e and parts connected therewith being incapable of sliding as before
explained. The result of this arrangement is that the fixed collar r on the shaft a
is by the sliding of the said shaft a made to bear against the collar of the loose
disc n and slide the said disc n upon the shaft and compress the pad, cushion, or
spring p. By the motion of the disc n it acts upon the friction disc m³ of the
drum m, causing the disc m³ of the said drum to bear upon and couple itself, by
frictional contact, to the sleeve disc es, sleeve e, and parts connected with the latter.
The positions described of the parts are their normal positions, and when the parts
are in these positions the whole of them rotate together.
The action of the lift or hoist is as follows:-
In order to raise the load the endless rope of the pulley or wheel d is drawn down
on the side proper to wind the rope or chain on the pulley or sheave c, and the
shaft a is rotated and with it the friction clutch e, e², e³, and as the large drum
disc m² is in frictional contact with the clutch disc e³ the said drum disc m² receives
motion from it, and the countershaft b is rotated through the pinion s and spur
wheel t and the load is raised. On loosing the rope passing over the hand pulley or
wheel d, the load being raised remains suspended, the back motion of the drum m
and shaft a being prevented by the pawls u³, u, engaging with their respective
ratchet wheels u and u³.
When it is wished to lower the load or weight the endless rope on the
wheel dis drawn down on the side opposite to that by which the raising
motion is produced. A backward motion is thereby given to the shaft a by

page_text: the retiring of the screw as in its screw box l. The pressure of the spring f on the
drum m is thereby relaxed, and the disc m² of the said drum retires from the disc es
of the sleeve. The drum m can now make a back movement for lowering the
weight, the shaft a, sleeve e, and disc n, being prevented from rotating by the
pawls u, u The pad, cushion, or spring p produces such an amount of friction on
the drum disc m³ as suffices to regulate the backward motion of the drum m and
the descending motion of the load. On liberating the rope of the pulley d after the
load has been lowered the quick threaded screw a of the shaft a by the expansion
of the spring fis drawn into the screw box l, and the drum m is again gripped by
the sleeve disc e³ and the apparatus is again ready for raising a load.
We will now describe the construction and action of the pawls u², u. Each
pawl is furnished with an eye which embraces the countershaft b, the said shaft
constituting the axis on which the pawls turn.
In the said countershaft b an annular groove v is made in which a friction pin w
is placed, the bottom of the said pin being made to bear forcibly against the
bottom of the said groove by the strong spring x on the upper side of the pawl.
Over the acting end of each pawl is a stop y for limiting its rising motion.
When the lift or hoist is lifting the load, the countershaft b turns in the direction
of the arrow (Figure 2), and the friction between the pin w and the shaft b is
sufficient to cause the pawl u to be lifted from its ratchet wheel us, and bear
against the stop y. As soon as the shaft 6 comes to rest, or the motion of the said
shaft b is reversed for lowering the load, the pawl u falls, and engaging with its
ratchet wheel prevents the back motion of the part to which the said ratchet
wheel is connected as before described. Both pawls us, u, act alike and move
simultaneously. The engaging of the pawls with and the disengaging of them
from their ratchet wheels are thus automatically effected, and the ratchet
mechanism is noiseless.
When steam power or power other than manual is employed to work the lift or
hoist, the arrangement represented in elevation in Figure 3, and indicated in
dotted lines in connection with the shaft a, Figure 1, is used for permitting of the
reversal of the motion of the shaft, the rope wheel d in this case being dispensed
with. On the shaft a a lever 2 turns loosely, the said lever carrying a pawl 4
pressed on by a spring, and linked to the beam or strut 5 by the chain 6; 7 and 8
are stops, between which the free end of the lever 2 works. Fixed on the shaft a
is a ratchet wheel 3, in which the pawl 4 may engage. When the lever 2 is in the
position represented, the pawl 4 gears with the ratchet wheel 3, and the shaft a
cannot rotate in the direction of the arrow, Figure 3. When the lever 2 is
depressed so as to come in contact with the stop 8, the pawl 4 is lifted from the
ratchet wheel 3 as indicated in dotted lines, and the motion of the shaft a may be
reversed.
When it is wished to reduce the length of the shaft a of the lift or hoist, the box
e may be dispensed with, and the drum m may be made hollow for the purpose of
containing the spring f, and the mechanism contained in the said box e².
In applying our Invention to small lifts, such as dinner lifts, or sack lifts, or
hoists, we dispense with the counter shaft b, and the lifting rope is wound upon
the drum m. Figure 5 represents in perspective a dinner lift; and Figure 6 in
perspective a sack lift or hoist, constructed as last described.
Our Invention is applicable to hoists or lifts for lifting or hoisting generally,
and may be used as a substitute for cranes, pile drivers, and other like machines.
When necessary, as in the case of cranes, a train of toothed wheels may be used for
driving the shaft.
Having now described the nature of our Invention and the manner in which the
same is to be performed, we wish it to be understood that we claim as our
Invention of "Improvements in Lifts or Hoists,"
First. The construction, arrangement, and combination of parts berein before
described and illustrated in Figures 1, 4, 5, and 6 of the accompanying Drawings,
whereby the motion of a shaft rotating in one direction is made to engage by

page_text: frictional contact with a drum working loosely on the said shaft, so as thereby to
couple the said drum to the said shaft, and raise the load connected with a chain
or rope winding upon the said drum or on a sheave or pulley on a countershaft,
the disengaging of the said drum from the shaft and the lowering of the load being
effected by giving motion to the driving shaft through a small angle in a direction
contrary to that proper for raising the load, the said load being suspended at any
height to which it may have been raised or lowered by loosing the endless rope
or chain of the hand wheel, or disconnecting the steam or other motive power from
the driving shaft, substantially as described and illustrated.
Secondly. The construction and arrangement of the parts of the automatic and
noiseless pawl mechanism, herein before described and illustrated in Figures 1 and
2 of the accompanying Drawings.
Thirdly. The mechanism hereinbefore described and illustrated in Figure 3 of
the accompanying Drawings for permitting of the reversal of the motion of the
shaft of the lift or hoist when driving by steam power or power other than
manual.
In witness whereof, we, the said David Edwards and Thomas Alexander,
have hereunto set our hands and seals, this Fifteenth day of September,
in the year of our Lord One thousand eight hundred and seventy nine.
Witness,
THOMAS THOMAS,
132, High Street,
Merthyr Tydfil.
(L.S.)
DAVID EDWARDS.
THOMAS ALEXANDER. (LS.)