IMPROVE- MENTS IN MACHINERY OR APPARATUS FOR RAISING AND LOWERING, MOVING, OR TRANSPORTING HEAVY BODIES
Year: 1868

page_text: LETTERS PATENT to Thomas Aldridge Weston, of Birmingham, in
the County of Warwick, Engineer, for the Invention of "IMPROVE-
MENTS IN MACHINERY OR APPARATUS FOR RAISING AND LOWERING, MOVING,
OR TRANSPORTING HEAVY BODIES."
Scaled the 28th August 1868, and dated the 6th June 1868.
PROVISIONAL SPECIFICATION left by the said Thomas Aldridge
Weston at the Office of the Commissioners of Patents, with his
Petition, on the 6th June 1868.
I, THOMAS ALDRIDGE WESTON, of Birmingham, in the County of
Warwick, Engineer, do hereby declare the nature of my said Invention
Tor "IMPROVEMENTS IN MACHINERY OR APPARATUS FOR RAISING AND LOWERING,
MOVING, OR TRANSPORTING HEAVY BODIES."
This Invention relates to a peculiar construction and arrangement
of apparatus applicable to windlasses, crabs, and capstans, whereby the
load is made self-sustaining and a perfect control is obtained in the
lowering motion.
According to this Invention as applied to a hoisting crab I place
the barrel loose upon a shaft, such shaft carrying a collar, against which
the outer end of the barrel abuts. The face of the opposite end of the
CDR/1

page_text: barrel carries or has formed concentrically upon it a circular inclined
surface or two semicircular inclined surfaces, somewhat similar to an
ordinary sliding clutch with inclined table. This inclined surface bears
against and engages with corresponding inclines formed upon or carried
by the boss of the main spur wheel, which is also mounted loosely
upon the same shaft. Upon the opposite or outer face of this spur
wheel there is fitted or formed an annular projection of larger
diameter than the said inclined, which bears against a corresponding
annular friction surface in the contiguous face of a ratchet wheel which
is fast on the said shaft, and is further secured against any longitudinal
motion on the shaft by a collar similar to the collar which retains the
barrel in its longitudinal position. A detent engaging with the said
ratchet wheel and carried by a pin in the frame of the crab or hoist
serves to retain the shaft from backward motion. One end of an
ordinary lifting chain is attached to the barrel, and on imparting motion
to the main wheel by a pinion and crank handle or otherwise in the
direction for hoisting the spur wheel will turn slightly upon the shaft
until the opposite inclines herein-before referred to are brought into close
contact with and tend to slide over each other, whilst at the same
time the spur wheel is brought into forcible contact with the side of the
ratchet wheel. The main shaft ratchet wheel, spur wheel, and barrel
are all thus frictionally connected and move together. On ceasing to
hoist the load will be maintained in suspension by the action of the
ratchet wheel and detent. On reversing the motion of the spur wheel
the inclined surfaces, on the end of the barrel follow the motion of
those on the spur wheel, thus keeping up the frictional connection by
which the load is sustained. It is obvious that the same or slightly
modified arrangements of self-acting frictional connection may be
supplied to other hoists, capstans, and lifting jacks; for example, in
larger or more powerful hoists the winding barrel described instead of
receiving the load direct by the chain wound upon its exterior may
have its exterior formed into a spur wheel, through which or through
a train of gearing if desired the load may be acted upon for hoisting
or lowering. Or the said barrel with the inclines on its end being
thus formed into a toothed wheel may engage with the toothed rack
bar of a lifting jack or with any other toothed rack which it is desired
to lift, lower, or make self-sustaining.

page_text: SPECIFICATION
in pursuance of the conditions of the Letters Patent,
filed by the said Thomas Aldridge Weston in the Great Seal Patent
Office on the 5th December 1868.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I. THOMAS
ALDRIDGE WESTON, of Birmingham, in the County of Warwick,
Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Sixth day of June, in the year of
our Lord One thousand eight hundred and sixty-eight, in the thirty-
first year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said Thomas Aldridge Weston, Her special
licence that I, the said Thomas Aldridge Weston, my executors,
administrators, and assigns, or such others as I, the said Thomas Aldridge
Weston, my executors, administrators, or assigns, should at any time
agree with, and no others, from time to time and at all times thereafter
during the term therein expressed, should and lawfully might make, use,
exercise, and vend, within the United Kingdom of Great Britain and
Ireland, the Channel Islands, and Isle of Man, an Invention for "In.
PROVEMENTS IN MACHINERY OR APPARATUS FOR RAISING AND LOWERING. MOVING
OR TRANSPORTING HEAVY BODIES," upon the condition (amongst others) that
I, the said Thomas Aldridge Weston, my executors or administrators,
by an instrument in writing under my hand and seal, should particularly
describe and ascertain the nature of the said Invention, and in what
manner the same was to be performed, and cause the same to be filed
in the Great Seal Patent Office within six calendar months next and
immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Thomas Aldridge Weston, do hereby
declare the nature of my said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in and by
the following statement, reference being had to the accompanying
Drawings, and in the letters and figures marked thereon, that is
to say:
My said Invention relates to a peculiar construction and arrangement
and apparatus applicable to windlasses, crabs, and capstans, whereby
the load is made self-sustaining, and where desired a perfect control
is obtained in the lowering motion; and consists essentially in the
application of circular or semicircular inclines, and of frictional

page_text: surfaces to the barrels gearing and sustaining ratchet wheels of hoisting
apparatus of all kinds, the action of the barrel and gearing being to
produce sustaining friction between the frictional surfaces, such
surfaces being forcibly pressed together by the inclines, both in hoisting
and lowering, whilst the pressure and friction serve also to sustain the
load.
According to one mode of carrying out my Invention as applied to
a hoisting crab, for example, I place the barrel loose upon a shaft,
such shaft carrying a collar against which the outer end of the barrel
abuts. The face of the opposite end of the barrel carries or has formed
concentrically upon it a circular inclined surface or two semicircular
inclined surfaces somewhat similar to an ordinary sliding clutch with
inclined teeth. The said inclined surface or surfaces bear against and
engage with a corresponding incline or inclines formed upon or carried
by the boss of the main spur wheel, which is also mounted loosely
upon the same shaft. These inclined surfaces acting together as
herein-before described, or in any other equivalent manner, constitute the
essential feature of my said Invention. Upon the opposite or outer
face or side of the spur wheel above referred to there is fitted or
formed an annular projection of larger diameter than the said inclines
which bears against a corresponding annular friction surface in the
contiguous face of a ratchet wheel which is fast on the said shaft,
and is further secured against any longitudinal motion on the shaft
by a collar similar to the collar which retains the barrel in its longi-
tudinal position. A detent engaging with the said ratchet wheel and
carried by a pin in the frame of the crab or hoist serves to retain
the shaft from backward motion. One end of an ordinary lifting
chain is attached to the barrel, and on imparting motion to the main
wheel by a pinion and crank handle or otherwise in the direction for
hoisting the spur wheel will turn slightly upon the shaft until the
opposite inclines herein-before referred to are brought into close contact
with and tend to slide over each other, whilst at the same time the
spur wheel is brought into forcible contact with the side of the ratchet
wheel. The main shaft, ratchet wheel, spur wheel, and barrel are
all thus frictionally connected and move together. On ceasing to hoist
the load will be maintained in suspension by the action of the ratchet
wheel and detent in combination with that of the inclined surfaces.
On reversing the motion of the spur wheel the inclined surfaces on
the end of the barrel follow the motion of those on the spur wheel,

page_text: thus keeping up the frictional connection by which the load is sustained.
It is obvious that the same or slightly modified arrangements of self-
acting frictional connection may be supplied to other hoists, capstans,
and lifting jacks; for example, in larger or more powerful hoists, the
winding barrel described instead of receiving the load direct by the
chain wound upon its exterior may have its exterior forced into a
spur wheel through which or through a train of gearing if desired
the load may be acted upon for hoisting or lowering. Or the said
barrel with the inclines on its end being thus formed into a toothed
wheel may engage with the toothed rack bar of a lifting jack, or
with any other toothed rack which it is desired to lift, lower, or make
self-sustaining.
And in order that my said Invention may be fully understood I
shall now proceed more particularly to describe the same, and for
that purpose shall refer to the several Figures on the annexed Sheet
of Drawings, the same letters of referénce indicating corresponding
parts in all the Figures.
Figure 1, on Sheet 1 of my Drawings, represents in plan a hoisting
crab constructed according to my said Invention.
A is the winding barrel, and B the spur wheel, both placed, loosely
upon the shaft C; D is a plain collar secured upon the shaft by a
key E F is a ratchet wheel firmly attached to the shaft, and further
secured against endway motion thereon by the collar G; H is an
ordinary pall hung to the frame of the crab; I, I, are square shanks
for the reception of winch handles carried by a shaft J, upon which
is mounted the pinion K gearing with the spur wheel B. The end
of the barrel next to the spur wheel B has cast or formed upon it
an incline or screw face A' in contact with a correponding incline
B' cast or formed upon the boss of the spur wheel B; these inclines or
screw surfaces are shewn in detail perspective at Figure 2 detached.
The boss B" of the spur wheel B in contact with the ratchet wheel
F forms therewith a pair of frictional rubbing surfaces of somewhat
larger diameter than the inclines A' B'. A pair of frictional faces of as
large diameter as convenient or practicable is also formed by the collar D
and the flange of the barrel A in contact with it.
The action of the crab in making the load "self-sustaining" when
the handles are released after hoisting, and in making the lower-
ing motion self-controlled, is as follows:-The direction in which
the
spur wheel B must be rotated for hoisting (indicated by the arrows)

page_text: is that in which one incline would ascend the other were the necessary
longitudinal motion upon the shaft permitted by the removal of one
of the collars D or G. A slight amount of play in this direction is
however allowed, which is indicated in the Drawing, Figure 1, by the
space separating the ends of the two inclines, one of which is supposed
to be advanced upon the other as far as possible under the applied
force for hoisting the load. Upon applying force through handles
which are fitted on to the square shanks I, I, and through the
pinion K in the direction for hoisting, the sloping face of the incline B
drives before it and imparts its rotatory motion to the incline A' and the
barrel A. Simultaneously with the rotatory motion thus transmitted
from one incline to the other a severe end thrust or longitudinal pressure
is produced upon the fixed collar D and upon the rubbing face of the
ratchet wheel F through the oblique action of the inclines upon
each other, or from their tendency to ascend each other, the incline A
upon the barrel tending to move in one direction under the pall of
the suspended load, and the incline B' having a contrary tendency
under the actuating power applied for hoisting. The end thrust thus
produced by the inclines A' and B' is sufficient to maintain the spur
wheel B and barrel A at rest under the force of a suspended load by
the resultant frictional action of the barrel flange upon the collar D
and the wheel boss B upon the side of the ratchet wheel F. The
shaft C, collar D, and ratchet wheel F are prevented from turning
backwards by the pall H. The collar D is made as large in diameter
as conveniently practicable in order to give increased frictional surface to
the adjacent barrel flange, by which greater durability is obtained under
the frictional action,and by which greater proportional friction is obtained
with a coarser or quicker pitch in the inclines than could otherwise
be produced. In practice I have found a pitch of ths of an inch
in a diameter of 4 inches will answer well, but the inclines may be of
any other proportions, varying with the nature or character of the
frictional surfaces upon which their oblique action takes effect. Thus
by making the frictional surfaces conical, or in effect cone clutches
yielding a greater amount of friction under any applied pressure, the
inclines may be correspondingly steeper or of greater inclination; again,
by introducing between the frictional surfaces the frictional discs
described in the Specification of my Patent, bearing date January
Twenty-nine, One, thousand eight hundred and sixty-three, No. 263,
as herein-after shewn and described; a much less degree of end pressure

page_text: suffices to couple the parts to which they are applied, and propor-
tionately the action of the inclines and the longitudinal strain upon the
shaft and collars is reduced.
Having explained the action of the crab in hoisting a load, and in
sustaining it when the handles are released, I will now explain the
action of the crab in lowering the load, by which the descending
motion of the load always arrests and controls itself, so that it can in
no case run away or descend more rapidly than is due to the back-
ward motion imparted to the winch handles. Upon rotating the spur
wheel B backwards so that the incline B' descends the incline A
simultaneously reducing the thrust and resultant friction of the barrel
flange upon the collar D so that the sustaining friction is thereby
partially withdrawn and is no longer sufficient to maintain the load,
the barrel then yields to the pull of the load, and it rotates upon the
shaft C following the rotatory motion of the incline B' and spur wheel.
This backward motion of the barrel and incline A' can in no case
exceed the speed imparted to the spur wheel and incline B', nor by
the force of the load can the incline A' drive the incline B' before it
in consequence of the greater diameter of the frictional surface of the
boss B acting against the side of the ratchet wheel F. In other words,
under any load, the frictional resistance between the side of the sta-
tionary ratchet wheel F and the adjacent boss B of the spur wheel arising
from the oblique thrust of the inclines thereon, is always greater than
the direct rotatory driving force of the incline A' upon the incline B'.
This result is obtained by the greater diameter of the frictional face B
over that of the incline B' together with the requisite fineness of pitch
or angle in the same. I have found in practice that with the incline
of the proportions herein-before mentioned an excess of one quarter of
an inch in the diameter of the face B over that of the inclines will
answer well. The lowering of the load therefore only continues during
the backward rotation of the spur wheel B and at the same speed, the
load remaining in suspension at any moment that the backward motion
of the handles ceases. Although I have stated that the boss B* must be
of greater diameter than the inclines, it is obvious that other means may
be adopted in order to obtain a superior frictional connection with the
ratchet wheel F or other stationary rubbing surface; thus the surfaces
at B and F may be made conical, or my patent friction discs herein-
before referred to may be introduced with the like object of making the
frictional connection due to the oblique action of the inclines superior

page_text: to their tendency to simultaneous rotation in the same direction. Should
the load not be required to remain in suspension nor yet to run away
wholly unchecked the frictional connection at B and F may be reduced
sufficiently by any of the means herein-before mentioned for varying the
same, as the most obvious of which I may mention the simple reduction
of the diameter of the boss B². Where lubrication of the rubbing
frictional faces can be obtained they may consist of iron upon iron,
otherwise one face being made of wood will give greater durability.
Where the self-sustaining action upon ceasing to impart the hoisting
motion is required, but in connection with a rapid dowering motion
under the control of the operator and not self-controlled, certain
modifications are requisite, as herein-after shewn and described.
Figure 3 represents an elevation of a sack hoist constructed according
to my Invention. A is the winding barrel, and B the rope wheel, both
placed loosely upon the shaft C; D is a collar fixed upon the shaft C
forming with the barrel flange a pair of frictional faces; A' is the incline
upon the barrel end; and B', the corresponding incline upon the boss
of the wheel B; F is a ratchet wheel fixed upon the shaft C, which
wheel is provided with internal teeth and the ordinary pall to prevent
it turning backwards; the boss B of the rope wheel and the adjacent
face of the ratchet F form a pair of frictional rubbing surfaces of larger
diameter than the inclines A', B', the relative proportions of which are
similar to those of Figure 1. The rotatory motion for hoisting and
lowering is imparted by a common endless rope placed in the grooved
edge of the wheel B. The self-sustaining action upon ceasing to hoist
and the self-arresting action in lowering are identical with the corre-
sponding actions described in reference to Figures 1 and 2.
Figure 4 represents in partial section and elevation a modification of
my Invention as applied to a double-acting hoist, or one with two
barrels. A, A, are the winding barrels placed loosely upon the shaft C;
B' is a collar fixed upon the shaft and having its opposite ends formed
into the two inclines b, b, in contact respectively with corresponding
inclines A formed upon or attached to the adjacent ends of the
barrels A, A; D, D, are fixed collars upon the shaft C, the rubbing
faces of which and the contiguous frictional faces of the internal toothed
ratchet wheels F, F, are of greater diameter than the inclines for the
purpose explained in reference to Figure 1. The barrel Hanges and the
contiguous faces of the ratchet wheels F, F, against which they rub

page_text: form frictional surfaces for sustaining the load in like manner to the
pair of surfaces in Figure 1 formed by the collar D and the adjacent
barrel flange. In this modification of my Invention the ratchet
wheels F, F, are loose upon the shaft C, and they are provided with
palls H of the ordinary kind, by which they are prevented from turning
backwards under the strain of the load or during the backward rotation
of the barrels. The action of the inclines upon the sustaining or
frictional surfaces is similar to that described in reference to Figure 1,
the load upon either barrel remaining in suspension or arresting itself
when lowered in like manner to the action of the arrangement,
Figure 1. The rotatory motion for hoisting and lowering is received
through the spur wheel B driven by any of the usual methods; or in
lieu of the spur wheel B a common rope wheel of sufficient size or
winch handles may be fixed direct upon the shaft C. If desired the
outer surface of the winding barrel A may be formed into chain wheels
with teeth to grasp the links of the chain. The length of the shaft may
be thus very much reduced, and one hoisting chain only will serve for
both chain wheels by applying it thus. Commencing at one end of
the same where the hook is placed for seizing the load, the chain
ascends, and passing over one chain wheel descends again, forming
a short loop or "bight," the other side of which ascending again passes
over the other chain wheel, and terminates in the other lifting hook.
This duplex hoist is thus made more compact and about one-half of the
length of chain only is requisite that would be required with the common
winding drums shewn in Figure 4.
Figures 5, 6, and 7 represent a "pulling crab" for hauling a chain
horizontally or in any other direction constructed according to my
Invention; Figure 5 is a side elevation; Figure 6, a plan; and Figure 7,
a sectional detail. C is the shaft with one end projecting so as to be
conveniently rotated by a lever or handle placed thereon at I. The
shaft has suitable bearings in a cast-iron frame which is formed with a
spout or guide through which the loose chain may pass from the chain
wheel A; the chain wheel A and ratchet wheel F are loose upon the
shaft, upon which is fixed the collar D and incline B'. The pair of
frictional surfaces for retaining the load or strain upon the chain are
formed by the side of the chain wheel A, and the contiguous side of
the ratchet wheel F. The pair of frictional surfaces formed by the
collar D and the contiguous face of the ratchet wheel F must be of larger

page_text: diameter. than the inclines A' and B', that is, if it be desired that the
lowering action be self-arresting, as explained with reference to Figure 1,
the ratchet wheel F. has the usual pall H to prevent backward rotation.
Figure 8 represents in elevation another mode of applying my Invention
to a hoisting crab differing from the arrangement shewn in Figure 1
inasmuch as that my improvements are in the present example applied
to the pinion and pinion shaft of the crab or other hoist in lieu of being
applied to the main shaft and winding barrel, as shewn in Figure 1. A is
the spur pinion, and F the ratchet wheel, both placed loosely upon the
shaft C; B' is the incline formed in one piece with the shaft itself or
fixed thereon. This incline.is in contact with a corresponding incline A
formed upon the pinion A. D is a collar keyed or fixed to the shaft,
and the rubbing face of the same together with the adjacent face of the
ratchet wheel-are of greater diameter than the inclines A', B', for the
purpose herein-before explained. The pair of frictional surfaces formed
by the other side of the ratchet wheel and the contiguous side of the
pinion by their frictional union under the oblique thrust of the inclines
act in sustaining the load against the pall or detent H. In this example
the lowering motion is self-arrested, as explained with reference to
Figure 1 and the subsequent Figures.
Figure 9 represents a "side winch" or "bracket crab" constructed
with my said improvements. A is the winding barrel (which may be
a chain wheel if desired), and F is the ratchet wheel, both placed loosely
upon the shaft C; B' is the incline secured to or formed in a piece with
the shaft C; the corresponding incline A' is formed upon the adjacent
end of the barrel A; D is a collar fixed securely to the shaft C and
flanged or enlarged to form together with the contiguous face of the
ratchet wheel a pair of rubbing surfaces of larger diameter than the
inclines; the other face of the ratchet wheel F and the contiguous
flange of the barrel A form together a pair of frictional surfaces, which
act in sustaining the load against the pall H hung by a pin to the
cast-iron framework by which the working parts are carried. The shaft
has a shank I to which is applied the usual winch handle, and the action
in hoisting and lowering is similar to that already described with
reference to Figure 1.
Figure 10 (Sheet 2) represents an elevation, partly in section, of a cap-
stan constructed according to my said Invention. C¹ is a fixed shaft with
its lower end firmly connected to the sole plate S by which the capstan

page_text: is secured in its place by screw bolts or in any convenient manner; C is
a hollow shaft, to the upper end of which is attached or fixed the large
collar D; B is the capstan head with mortises or sockets a, a, to receive
the ends of the capstan bars or handspikes, and its lower side is formed
with the incline or screw face B' in contact with the corresponding screw
face or incline A¹ formed upon the upper end of the drum A. The capstan
head B and drum A are placed loosely upon the hollow shaft C, the lower
end of which has fixed to it by a screw thread or otherwise the collar G
with a conical exterior corresponding to the conical interior surface of the
drum with which it has frictional contact. The collar G has a series
of sliding bolts or palls H engaging successively with the ratchet teeth F
formed in the sole plate S for preventing backward rotation of the hollow
shaft C. The action of the conical friction surfaces of the collar G and
drum A in resisting backward motion of the said drum under the strain
upon a rope wound thereon is similar to the action of the corresponding
parts in the examples herein-before described, with the further advantage
of increased friction from the conical form of the said surface. The
friction surfaces formed by the capstan head B and the adjacent lower
face of the collar D are of larger diameter than the inclines for the
purpose herein-before explained, although by giving them the conical
form of the collar G the same result of superior friction could be obtained
even in a less diameter than that of the inclines. The advantages
gained in a capstan thus constructed according to my said Invention
are similar to those herein-before explained in connection with the pre-
ceding Figures.
Figure 11 represents an elevation and partial section of one mode of
applying my said Invention to the rack bars or toothed racks of lifting
jacks, sluice valves, camera stands, or other apparatus having toothed
racks which require to be lifted and lowered or retained in any desired
position. W is an ordinary toothed rack of straight or curved form; W'
is a pinion geared thereto and attached to the shaft C; fixed upon the
shaft C is the incline or screw faced collar B' and also another collar D;
placed loosely upon the shaft is the circular boss of the lever handle
having the incline A' formed thereon, and also the ratchet wheel F
engaging with the pall H hung or secured upon the framework (not
shewn in my Drawing) carrying the shaft C and rack bar W. One pair
of the frictional surfaces is formed by the curved or conical side of the
collar D and the adjacent side of the ratchet wheel F. The other pair

page_text: of frictional surfaces is formed by the other side of the ratchet wheel F
and the side of the boss of the lever handle with which it is in
contact. The action and effect of the two pairs of frictional faces
together with that of the inclines is similar to that of the foregoing
examples. The lifting and lowering motion is imparted to the rack by
the rotatory motion of the lever handle in either direction, the load
or strain upon the rack transmitted through the pinion W₁ to the
frictional surfaces and inclines being retained when the handle is
released and made self-arresting in lowering in the manner herein-
before described.
Figure 12 represents an elevation of a modification of my said
Invention as applied to a hoist, in which modification the load remains
in suspension at any moment that the hoisting motion is withdrawn
through the self-acting frictional surfaces and inclines, as herein-before
explained, but in combination with this self-sustaining action during
the hoisting motion and upon its ceasing is a rapid lowering action
under perfect control of the operator, but not as in the preceding
examples self-arresting.
Figure 13 are details shewing the ratchet wheel F in elevation and
section. X is an ordinary winding barrel attached to the shaft C, upon
which are also fixed the collars D and G; loosely upon the shaft C are
placed the spur wheel B and ratchet wheel F, which abuts against a
common pall in the usual manner. The ratchet F has its face recessed
This
and formed so as to receive and engage with the wooden disc c.
'disc may have small spiral springs c' sunk partly into it in order to
press it outwards against the adjacent face of the collar D, so as to
ensure frictional contact therewith when no pressure is applied by the
action of the inclines, which in this example are formed respectively
upon the contiguous faces or bosses of the said ratchet wheel F and
spur wheel B. One pair of the friction faces is formed by the ratchet
wheel F and collar D. The other pair of friction faces is formed by
the collar G and adjacent boss of the spur wheel B.
The action is as follows:-Upon rotating the spur wheel B so that
the incline B¹ formed thereon tends to ascend the incline A¹ upon the
ratchet F the oblique action or longitudinal thrust of the said inclines
upon the two pairs of friction surfaces in a somewhat similar manner
to that previously explained serves to transmit the rotatory motion
of the spur wheel B to the shaft C and barrel X. Upon withdrawing

page_text: the hoisting motion the load remains suspended through the said
frictional action of the inclines and rubbing faces, but upon rotating
the spur wheel in the contrary direction, so that the pressure of the
inclines is reduced and the friction correspondingly diminished upon
the rubbing faces of the two collars D and G, the barrel may be allowed
to rotate backwards under its appended load at any desired speed until
arrested by again rotating the spur wheel in the direction for hoisting,
whereupon one incline will ascend the other, and the pressure upon
the rubbing faces is thereby restored and sufficient friction induced to
stop the backward rotation of the barrel. In the last-described example
(Figures 12 and 13) it is advantageous to make the pair of rubbing
surfaces formed by the collar G and wheel boss B of the same or rather
less diameter than the inclines instead of making them larger as in the
preceding examples, so that the backward strain under a load which
the collar tends to transmit frictionally to the adjacent boss of the spur
wheel B shall be incapable of overcoming the frictional adhesion of
the two inclines to each other so as to make the incline on the spur
wheel descend the other incline, thereby reducing the frictional action
by which the load is sustained and permitting it to run down.
practice an excessive frictional connection of the parts more than is
actually needed to raise and retain the load is obtained by making the
inclines of the flat inclination particularly described with reference to
Figure 1, and with this excess of frictional connection the reduction of
the collar G to a less diameter than the inclines is not always essential,
although it is preferable for further security from accident.
In
Figure 14 represents in elevation, partly in section, the pinion and
shaft a hoisting crab constructed according to my said Invention
and having applied thereto the quick lowering action last described,
together with the frictional discs of my before-mentioned Patent. C is
the pinion shaft; D, a solid collar formed thereon; and B' is the screw
face collar or incline in contact with the other incline A' formed upon
the outer boss of the ratchet wheel F. The ratchet wheel F and pinion A
are loose upon the shaft. The ratchet wheel abuts against the usual
pall, and has an inner boss f of square exterior to carry the two iron
friction discs. The pinion a¹ is formed with a short drain to carry
the three wood discs f, f". These discs serve to increase or improve
the frictional connection of the pinion and ratchet under the applied
pressure of the inclines according to my said former Patent, but are

page_text: not absolutely essential to the efficacy of this my present Invention.
The pinion shaft is actuated by the usual winch handles, the rotation
of the same in one direction communicating the hoisting motion or
serving to check the lowering action produced by their contrary motion.
Dispatch and safety are thus obtained through the instant control
afforded by the winch handles over the load at all times.
Figure 15 represents a similar arrangement to that last described with
further modifications adapting it for use upon a pinion shaft requiring
the hoisting motion to be applied by rotating it in either direction,
as in certain well-known forms of "two-speed" or "double purchase"
crabs. The ratchet wheel F is double, having two sets of teeth, one
right hand and the other left, which engage with one or other of two
ordinary palls adapted thereto. The two iron discs f' are carried by
the squared end F of the pinion boss, and the three wooden discs f"
by the short drum formed upon the ratchet wheel F. The ratchet F,
the pinion A, the collars D, and incline B' have the same relative action
with each other as the corresponding parts in the arrangement last
described, but the screw or incline faced collar B' has a double incline
upon it instead of the single one last described, that is, one-half of its
face slopes one way and one half the other, the two surfaces being
respectively half turns of right and left hand screw surfaces or inclines,
each incline meeting the other at its highest and lowest point. The
corresponding double incline A' is formed upon the ratchet F. By
turning the shaft C in either direction the oblique thrust of one or other
of the said inclines acts upon the frictional surfaces precisely as in the
example, Figure 14, and in like manner the reversing of the rotation
withdraws the pressure of the incline and permits a quick backward
motion of the pinion A under the strain of the load. To hoist by
a contrary motion of the shaft to that last employed, the pall previously
in action must be thrown out of gear with its ratchet teeth, and the
other pall must be allowed to act upon the other set of corresponding
teeth. The motion of the handles or shaft which previously affected
the hoisting and lowering will then have a contrary effect, producing
(vice versa) lowering and hoisting.
Figure 16 represents an identical arrangement to the one shewn in
Figure 8, with the further addition of the friction discs shewn in
Figures 14 and 15 for the purpose of diminishing the end thrust or
oblique action of the inclines necessary to sustain the load and control

page_text: it by friction.
With the larger frictional area thus obtained by the
friction discs of my prior Patent herein-before referred to the pitch or
inclination of the screw faces or inclines may be proportionately
increased so as to reduce their oblique action and likewise the longi.
tudinal strain upon the shaft and collars, greater durability and smooth-
ness of action is also thereby obtained.
Figure 17 represents a folding handle which may be conveniently
used with the crab, Figure 8, and other similarly arranged hoists.
Figure 18 represents a safety pall or double pall which engages
simultaneously with two teeth of the ratchet wheel, where the teeth
are as shewn in the Drawing of equal length with the space between the
two palls, or by making the space between the palls greater or less than
the length of the teeth they are caused to act alternately.
Having now described and particularly ascertained the nature of
my said Invention, and the manner in which the same is or may be used
or carried into effect, I would observe in conclusion that what I consider
to be novel and original, and therefore claim as the Invention secured
to me by the herein-before in part recited Letters Patent is,-
First. The application and use to and in machinery or apparatus for
raising, lowering, moving, or transporting bodies of rotating inclines
acting together in combination with frictional surfaces so as to produce
endway thrust and friction, substantially as and for the purposes herein-
before described.
Second. The peculiar constructions, arrangements, and combinations of
machinery or apparatus for raising, lowering, moving, or transporting
bodies, as herein-before described and illustrated by my Drawings.
In witness whereof, I, the said Thomas Aldridge Weston, have to this
my Specification set my hand and seal, the Fourth day of Decem-
ber One thousand eight hundred and sixty-eight.
THOS. A. WESTON. (L.S.)