IMPROVEMENTS IN LIFTS OR HOISTS AND OTHER ELEVATORS."
Year: 1881

page_text: LETTERS PATENT to David Edwards, of Cardiff, in the County of Glamorgan,
Carpenter, for an Invention of "IMPROVEMENTS IN LIFTS OR HOISTS AND
OTHER ELEVATORS."
PROVISIONAL SPECIFICATION left by the said David Edwards at the Office
of the Commissioners of Patents on the 1st March 1881.
DAVID EDWARDS, of Cardiff, in the County of Glamorgan, Carpenter.
"IMPROVEMENTS IN LIFTS OR HOISTS AND OTHER ELEVATORS."
My Invention has reference to an Invention for which Letters Patent were
granted to me and Thomas Alexander, of Cardiff, on the 27th day of March, 1879,
No. 1223, and consists of the improvements herein after described in the lifts or
hoists described in the Specification of the said Letters Patent, by which improve-
ments the mechanism is simplified, and lifts or hoists or elevators produced in
which the load is automatically suspended at any height to which it may have
been raised, and readily lowered to any extent by giving motion to the winding
shaft in a direction contrary to that by which the raising is effected, the load being
automatically suspended in any position to which it may have been lowered on
ceasing to give a backward motion to the shaft.
I will describe my improvements in connection with a lift.
On the shaft of the lift, which shaft is capable of a rotary motion, is a tube or
sleeve occupying only a portion of the shaft and capable of rotating freely on the
said shaft. The outer end of this sleeve, that is, the end of the sleeve nearest the
end of the shaft, carries a ratchet wheel with which a pawl hinged to the fixed
framing of the hoist engages.
The other or inner end of the said, sleeve carries a drum, the edges of which are
conical and constitute the male parts of two conical clutches. The shaft also
carries two discs situated respectively on opposite sides of the double coned drum
last described. The said two discs have on their inner or opposed faces hollow
conical depressions of a size and shape suitable for the double coned drum to engage
with. The outer hollow conical disc, that is, the hollow conical disc most distant
from the ratchet wheel, is fixed to the shaft and is the only part which is

page_text: permanently fixed thereto. The other or inner conical disc is fixed to a second
sleeve working on the first nained sleeve and capable of a rotary motion and also
a limited sliding motion thereon. This second sleeve constitutes the winding drum,
on which the raising chain is coiled when a load is raised. The two hollow conical
discs are connected together by rigid or flexible links. When the hollow conical
discs are in such relative positions that the links connecting them are parallel to
the shaft they are at their greatest distance apart and do not grip between them
the double coned drum. When however the hollow conical discs are in such
relative positions that the links connecting them take oblique positions the said
hollow coned discs are drawn together; they then grip the double coned drum
tightly and all the parts are geared together.
The action of the parts is as follows:-When the shaft is turned in the direction
proper to raise the load the resistance of the load causes the links to take the
oblique position, which results in the gearing of the parts together, and the turning
of the shaft effects the winding of the chain and the raising of the load. The
pawl and ratchet wheel prevent the backward motion of the shaft so long as the
parts are geared together and the raised load is retained in whatever position it
may have been brought to. When it is wished to lower the load the shaft is
turned in the backward direction; this motion bringing the links nearer to
parallelism with the shaft the clutches are slackened and the winding drum being
free to take a backward motion the descent of the load is permitted, the descent
..continuing only so long as the backward motion of the shaft is continued.
Instead of the double clutch described a single clutch may be employed.
In the single clutch arrangement rigid links are employed, and the gearing of
the clutch is effected by a thrusting action of the said links, that is, by the said
links assuming positions more nearly parallel with the shaft than when they are in
the ungearing position.
When it is wished to use steam or other motive power instead of hand power
the gearing of the apparatus with the said motive power may be effected by toothed
wheels or other gearing.
The application of my improvements to elevators other than lifts differs in no
essential respect from its application to a lift, as herein described.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said David Edwards in the Great Seal Patent Office on the 30th
August 1881.
DAVID EDWARDS, of Cardiff, in the County of Glamorgan, Carpenter.
"IMPROVEMENTS IN LIFTS OR HOISTS AND OTHER. ELEVATORS."
My Invention has reference to an Invention for which Letters Patent were
granted to ine and Thomas Alexander, of Cardiff, on the 27th day of March 1879,
No. 1223, and consists of the improvements herein after described in the lifts or
hoists described in the Specification of the said Letters Patent, by which improve-
ments the mechanism is simplified, and lifts or hoists or elevators produced in
which the load is automatically suspended at any heights to which it may have
been raised, and readily lowered to any extent by giving motion to the winding
shaft in a direction contrary to that by which the raising is effected, the load being
automatically suspended in any position to which it may have been lowered on
ceasing to give a backward motion to the shaft.
I will describe my improvements in connection with a lift.
On the shaft of the lift, which shaft is capable of a rotary motion, is a tube or
sleeve, occupying only a portion of the shaft, and capable of rotating freely on the
said shaft. The outer end of this sleeve, that is, the end of the sleeve nearest the
end of the shaft, carries a ratchet wheel, with which a pawl hinged to the fixed
framing of the hoist engages.
The other or inner end of the said sleeve carries a drum, the edges of which are
conical, and constitute the male parts of two conical clutches.
The shaft also carries two discs situated respectively on opposite sides of the
double coned drum last described. The said two discs have on their inner or
opposed faces hollow conical depressions of a size and shape suitable for the double
coned drum to engage with. The outer hollow conical disc, that is, the hollow
conical disc most distant from the ratchet wheel, is fixed to the shaft, and is the
only part which is permanently fixed thereto.
The other or inner conical disc is fixed to a second sleeve working on the first
named sleeve, and capable of a rotary motion, and also a limited sliding motion
thereon. This second sleeve constitutes the winding drum on which the raising
chain is coiled when a load is raised. The two hollow conical discs are connected
together by rigid or flexible links. When the hollow conical discs are in such
relative positions that the links connecting them are parallel to the shaft they are
at their greatest distance apart, and do not grip between them the double coned
drum. When however the hollow conical discs are in such relative positions that
the links connecting them take oblique positions the said hollow coned discs are
drawn together; they then grip the double coned drum tightly, and all the parts
are geared together.
The action of the parts is as follows:-When the shaft is turned in the direction
proper to raise the load the resistance of the load causes the links to take the oblique
position, which results in the gearing of the parts together, and the turning of the
shaft effects the winding of the chain and the raising of the load. The pawl and
ratchet wheel prevent the backward motion of the shaft, so long as the parts are
geared together, and the raised load is retained in whatever position it may have
been brought to. When it is wished to lower the load the shaft is turned in the
backward direction; this motion bringing the links nearer to parallelism with the
shaft the clutches are slackened, and the winding drum being free to take a
backward motion the descent of the load is permitted, the descent continuing only
so long as the backward motion of the shaft is continued.
Instead of the double clutch described a single clutch may be employed. In the

page_text: .
single clutch arrangement rigid links are employed, and the gearing of the clutch
is effected by a thrusting action of the said links, that is, by the said links
assuming positions more nearly parallel with the shaft than when they are in the
ungearing position.
When it is wished to use steam or other motive power instead of hand power
the gearing of the apparatus with the said motive power may be effected by toothed
wheels or other gearing.
The application of my improvements to elevators other than lifts differs in no
essential respect from their application to a lift, as herein described.
I will now proceed to describe with reference to the accompanying Drawings the
manner in which my Invention is to be performed.
Figure 1 represents in side elevation, Figure 2 in end elevation, and Figure 3 in
plan a hand worked lift constructed according to my Invention; Figure 4
represents a longitudinal section of the clutch mechanism of the lift drawn to a
larger scale.
The same letters indicate the same parts in Figures 1, 2, 3, and 4. a is the
principal shaft of the lift; and b is the countershaft. The said principal shaft a is
capable of a rotary motion in its bearings, and carries at one end a pulley or
wheel c, over which an endless hand worked rope or chain passes. By means of
this rope or chain and pulley the lift is worked, as herein after described. On the
shaft a is a tube or sleeve marked d and e, the said sleeve being capable of rotating
freely on the said shaft. The part d of the sleeve carries a ratchet wheel f, with which
the pawl g turning on the countershaft b engages. The other part e of the rotating
sleeve d, e, consists of a flanged drum, and constitutes two clutches, the acting faces of
which may either be conical or plain, as represented in the sectional view, Figure 4.
h, i, are two discs situated respectively on opposite sides of the flanged drum or
double clutch e, the acting faces of which clutch e may either be conical when the
acting faces of the discs h, i, are conical, or plain, as represented in the Drawing.
The disc i is fixed to the shaft a by a key and the screw pin k. The disc i is the
only part of the clutch mechanism which is permanently fixed to the shaft a.
The other disc h forms part of a sleeve h², which sleeve h² is capable of turning
and sliding upon the first described or principal sleeve d. The second sleeve h²
has a pinion h³ upon it with which the toothed wheel on the countershaft 6 gears
(see Figures 2 and 3). The said countershaft b carries the pulley or wheel m over
which the raising rope or chain is coiled for supporting the load to be raised.
But the second sleeve h² in small lifts may constitute the winding drum on which
the raising chain or rope is coiled. The two discs h, i, on opposite sides of the
drum e are connected together by the rigid links p, p, secured to the said dises in
the manner represented in Figure 4. When the links p, p, are parallel to the shaft a
the discs h, i, are at the greatest distance apart, and do not grip between them the
flanged drum e, and the shaft a turns without the sleeve d, drum e, and ratchet
wheelf. When however the links p, p, take an oblique position the two discs h, i,
are drawn together, and they grip between them the flanged drum e, and all the
parts of the clutch mechanism are geared together, that is to say, the sleeve d,
drum e, and the second sleeve h² and its disc h move with the shaft a to which the
other disc is fixed. When the shaft a is turned in the proper direction by means
of the endless rope of the pulley c to raise the load, the resistance of the load
transmitted through the shaft b, toothed wheel l, pinion h³, and sleeve h² to the
disch causes the links p, p, to take a position oblique to the shaft a, thereby
sliding the sleeve h² on the sleeve d, and causing the flanged drum e of the said
sleeved to be gripped between the two discs h and i. The result of the sliding of
the sleeve h² is the gearing of the parts d, e, f, to the shaft a, the whole of the
parts of the gearing now moving together, so that by the turning of the shaft a by
the endless band and pulley c the motion of the said shaft is transmitted through
the sleeve d, pinion h³, and toothed wheel to the counter shaft b on which the
pulley m carrying the load is fixed and the load is raised, the pawl g and ratchet
wheel preventing the backward motion of the shaft so long as the parts are

page_text: geared together, and the raised load is retained in whatever position it may have
been brought to.
In order to lower the load the shaft a is turned in the backward direction. This
motion allows the second sleeve A² to slide towards the ratchet wheel f, by bringing
the links p, p, nearer to parallelism with the shaft. The two clutch discs h, i, are
thereby slackened on the drum e, and the sleeve his free to take a backward
motion. The said sleeve h³ is thereby ungeared from the shaft a, and is free to
rotate in a backward direction on the principal sleeve d so as to permit the load
on the pulley m to descend, the descent continuing only so long as the backward
motion of the shaft a is continued. Thus the load is automatically suspended at
any height to which it may have been raised, and readily lowered to any extent
by giving motion to the winding shaft b in a direction contrary to that by which
the raising is effected, as described. The discs h, i, and drum e may be covered by
the sheet metal casing 9 when the lift is exposed to the weather, but the said
casing may be omitted.
Instead of the rigid links p, p, chain or other flexible links may be employed
with the same effect.
In order to cause the weight, as in cage hoists, to descend should the empty cage
not be sufficiently heavy to overcome the friction of the gearing, I combine with
the clutch discs h, i, of the gearing two stops, the said stops having for their object
to effect the backward or descending rotation of the disc h when the links p, p,
have come into their parallel position.
These stops are indicated in dotted lines in the sectional plan, Figure 4, and in plan
in Figure 4A, and elevation in Figure 4B, in combination with the two clutch discs h
and . The stop on the clutch disc h is marked x, and the stop on the clutch disc i
is marked y. The ends of these stops overlap one another as represented. When
the load is being lifted the said stops x, y, separate, but in the descending rotation of
the said discs h, i, the said stops come in contact, as best seen in the plan Figure 4ª,
and the two discs are made to rotate together, the links p, p, being thus prevented
by the said stops x, y, from taking an oblique position in the return or back rotation
of the discs h, i.
I make the pawl g which gears with the ratchet wheel f fixed on the loose
sleeve d automatic and silent in the manner illustrated in Figure 4°.
'
The eye or bush g2 of the pawl g turns upon the counter shaft b. On the said
shaft 6 are two collars g³, gt. Between one side of the eye g² and the fixed collar g'
is a coiled spring g³ which presses the eye of the pawl forcibly against the collar g³.
96, Figure 3, is a stop for limiting the rising motion of the pawl g. On lifting the
load the rotation of the shaft b in the lifting direction causes sufficient friction
between the eye of the pawl g and collar g³ to lift the said pawl from its ratchet.
wheelf, so that during the raising of the load the pawl does not slip over the teeth
of the ratchet wheel f. On the shaft b coming to rest a slight reversal of its motion
takes place, and the pawl g engaging with the ratchet wheel ƒ prevents the back
motion of the sleeve d, as before described.
An ordinary pawl may be used instead of the noiseless pawl represented.
Figure 5 represents in longitudinal section, and Figure 6 in side elevation,
mechanism constructed according to my Invention provided with a single clutch.
a is the shaft of the lift; i is the. conical disc free to rotate on the shaft a, having
in this arrangement the ratchet wheel attached to it for the pawl on the counter-
shaft to engage with; r is a sliding and rotating sleeve which is geared by the
pinion to the counter shaft; 8 is a disc fixed to or made in one piece with the
sleeve r. On the said sleeve is a hollow conical collar ³ which engages with
the conical disc i. Opposite the disc s is a second disc t, fixed by a key to the
shaft and rotating with it, its position on the shaft being adjusted and fixed by
the lock nuts at u. Between the two discs 8, t, is a coiled spring v, by which they
are pressed apart. The two discs s, t, are connected together by the rigid links w, w,
having spherical ends which seat themselves in properly shaped seats in the
discs 8, t. The links w, w, are not arranged parallel to the shaft a, but are inclined

page_text: ཝཱ་
thereto, as best seen in Figure 6. When the shaft a is turned for raising the load
the rotation of the disc t making the links w, w, approach parallelism, the discs and
sleever are made by the thrusting action of the said links to cause the clutch
disc to press against and grip the conical disc i so as to gear the sleeve and
its disc 8 with the shaft a, and effect the raising of the load through the pinion ³
and gearing connected therewith.
When the lift, hoist, or elevator is to be worked by steam or other motive power
the hand pulley c and its endless band are replaced by toothed or other gearing.
Having now described the nature of my Invention, and the manner in which the
same is to be performed, I wish it to be understood that I claim as my Invention
of "Improvements in Lifts or Hoists and other Elevators,"-
First. The construction and combination of the parts of the clutch gearing
herein before described and illustrated in Figures 1, 2, 3, and 4 of the accompanying
Drawings, that is to say, coupling the fixed clutch disc i on the rotating shaft of
the lift, hoist, or elevator with the clutch disc h, on the sliding sleeve h², constituting
the winding drum, or through which the shaft carrying the winding drum or pulley
is worked, by means of rigid or flexible links, so that when the shaft is turned in
the direction proper to raise the load the resistance of the load causes the links to
take an oblique position, and thereby gear the parts of the clutch together, the said
coupled clutch discs i and h and sliding sleeve h² being constructed and combined
with the other parts of the lift, hoist, or elevator, and acting substantially as
described and illustrated.
Also the combination with the coupled clutch discs h and i of the stops x, y,
shown in Figures 4, 44, and 4³, for the purpose and substantially as described and
illustrated. Also the combination with the countershaft of the lift, hoist, or elevator
of the automatic and silent pawl described and represented in Figure 4° of the
Drawings.
Secondly. The construction and combination of the parts of the single clutch
arrangement herein before described and illustrated in Figures 5 and 6 of
the accompanying Drawings, in which the gearing is effected by the thrusting
action of rigid links.
In witness whereof, I, the said David Edwards, have hereunto set my hand
and seal, this Twentieth day of August, in the year of our Lord One
thousand eight hundred and eighty one.
Witness,
D. C. THOMAS,
34, St. Mary Street,
Cardiff.
DAVID EDWARDS. (L.S.)