An Improved Frictional Self-sustaining Apparatus for Hoists and other Lifting Appliances, Friction Pulleys, and Couplings.
Year: 1890

page_text: Date of Application, 23rd July, 1890
Complete Specification Left, 8th May, 1891-Accepted, 23rd July, 1891
PROVISIONAL SPECIFICATION.
An Improved Frictional Self-sustaining Apparatus for Hoists and
other Lifting Appliances, Friction Pulleys, and Couplings.
We, JOHN WALTER BROOKE, of the Adrian Iron Works, Lowestoft in the
County of Suffolk, Engineer, and WILLIAM ROBERT HAY of North Grove
Cottage, Albert Street, Lowestoft aforesaid Engineer, in the employ of the said
John Walter Brooke do hereby declare the nature of our said invention to be as
follows:-
This invention relates to an improved means of automatically sustaining loads
while being raised or lowered by hoists, or other lifting appliances, thereby
preventing the load from descending when the power is withdrawn, or descending
with undue speed when power is applied to lower the same. We accomplish this
by means of a cylindrical projection or box, cast on, and concentric with the
bearing, which is provided for one end of the driving shaft of lifting appliance.
In this cylindrical projection or box we fit a steel hoop or ring, in which is cut
an elliptical hole, extending the full width and thickness of the ring, thereby
dividing it at this point, and allowing freedom of expansion. In this hole or
opening is fitted a forging of steel projecting inwards towards the driving shaft,
and forged with or attached to a double ended lever, in a position parallel with the
shaft. One end of this lever is carried by a plate, which is placed in the inner end
of the box, the other end is carried by a pinion driving the hoist or lifting
appliance; or by the lifting wheel direct on the driving shaft; the plate and pinion
have each a certain amount of movement on the shaft, but are driven simul-
taneously by feather, key, or other suitable appliance on the shaft.
The action of the apparatus is such that, when the driving shaft is being turned
round to lift, the key or drivers engage with the plate and pinion, causing them to
revolve in the same direction, they carrying the lever with the elliptical expanding
pin, which is inserted in the recess of the steel expanding ring: the whole, while
being driven, remains parallel with the centre line of the shaft; and, while in this
position, the steel expanding ring is free to revolve in the cast iron box.
Immediately the power is withdrawn, the weight of the load causes a slight reversal
of the pinion or wheel, to which is attached one end of a lever, the other end of
the lever and carrying plate remaining in a stationary position. The lever is thus
thrown out of parallel with the centre line of the shaft, and thereby slightly turns
the expander in the steel ring, which makes the ring fast by frictional contact with
the inner circumference of the cast iron box, thus preventing any further movement
of the pinion or wheel, and holding the load securely suspended.
To lower, the movement of the driving shaft is reversed, the pinion or wheel is
now in advance of the motion, and the drivers on the shaft, on being moved
forward, come in contact with the carrying plate, thus bringing the lever into a
parallel position, contracting the friction ring and allowing it to slip, and the
load to descend with a regular motion while the power is being applied to driving
shaft.
We do not confine ourselves to an elliptical hole or division of the strap or ring,
as it may be otherwise formed for effecting the same object.
In some cases we make our friction box a separate casting from the bearing,
securing it by lugs or projections, through which pass the stays of the machine
frame; or, where quick lowering is required, we make the friction box as a
cylindrical ring and surround it with a brake strap, which, when tightened, will
prevent it from revolving but will still admit of the free action of the sustaining

page_text: mechanism, as before described, but on slackening the brake strap, the whole is
allowed to revolve, and the load to descend at any required speed.
In a modification of our invention we apply it as a friction pulley to hoisting or
other belt driven machinery. In this arrangement the inside periphery of a pulley is
substituted for the friction box; the friction ring is carried by a disc, which is
keyed on the shaft, the pulley with belt being free to revolve on the shaft until the
expanding lever (which in this case is single ended) receives a twisting motion or
movement, as before described, and, expanding the ring in the pulley, thereby
causing the shaft to be driven with the pulley.
Dated this 23rd day of July 1890.
GEO. DOWNING,
8, Quality Court, London, W.C., Agent for Applicants.
COMPLETE SPECIFICATION.
An Improved Frictional Self-sustaining Apparatus for Hoists and
other Lifting Appliances, Friction Pulleys, and Couplings.
We, JOHN WALTER BROOKE, of the Adrian Iron Works, Lowestoft, in the
County of Suffolk, Engineer, and WILLIAM ROBERT HAY, of North Grove
Cottage, Albert Street, Lowestoft aforesaid, Engineer, in the employ of the
said John Walter Brooke, do hereby declare the nature of our said invention
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 improved means and appliances for automatically
sustaining loads while being raised or lowered by hoists or other lifting apparatus;
and its object is to prevent the load descending when the power is withdrawn, or
descending with undue speed when power is applied to lower the same.
We
accomplish this by means of a cylindrical projection or box, cast on and concentric
with the bearing which provided for supporting one end of the driving shaft of
the lifting appliance. In this stationary projection or box we fit a split hoop
or ring (preferably of steel) having semi-elliptical gaps formed in the meeting ends
of the ring. An elliptical plug attached to a lever is placed in the gaps or
openings. When the lever is parallel with the axis the ring is out of contact with
the stationary cylinder; but when the lever is caused, by suitable means, to assume
a diagonal position relatively to the axis, automatically, the elliptical plug forces
apart the meeting ends of the brake ring, the consequent enlargement whereof
causes frictional contact between it and the stationary cylinder, whereby the
rotation of the drum or other lifting appliances, is retarded or stopped, as
required.
And in order that our said invention may be particularly described and
ascertained, reference is hereby made to the accompanying drawings, in which
similar letters of reference indicate corresponding parts.
Fig. 1 is a longitudinal section, and Fig. 2 a transverse section, on the line 1-2
of Fig. 1, showing one method of carrying out our invention.
Figs. 6, 7, 8 and 9 illustrate other modifications, the remainder of the drawings
being detail views of parts of the apparatus.
Referring to Figs. 6 and 7, c is a drum or barrel, mounted loosely on the
spindle a, the spindle being actuated by the handle h, or any other suitable means.
85 are the fixed bearings, in which the spindle revolves. 6 is the fixed brake
cylinder, cast in one with the bearing s. d is the brake hoop, consisting of a split
steel ring, the meeting edges or ends of which are formed with semi-elliptical
recesses d'. The meeting ends of the ring d, are sometimes extended inwards, (as
shown in Figs. 2 and 11). e is a double ended lever, carrying an elliptical plug or
cam e¹. One end of the lever e is loosely pivoted in a hole n formed in the barrel c,
and the other end of the lever e is loosely pivoted in a hole in the idle disc f, loose
on the spindle a, 9 (see Figs. 1 and 2) is a driver, fast on the spindle a. The

page_text: barrel c and disc fare respectively provided with lugs or projections c¹³ fɩ ƒª.
These lugs are so placed as to allow the barrel c and disc a limited amount of
rotative motion relatively to and independently of the spindle a.
с
When power is applied to the spindle a by means of the handle h or otherwise,
for lifting the load suspended from the barrel c, the driver g engages the lugs c
and (see Figs. 2 and 5) on the barrel c and plate f. The lever e is thus carried
round in a parallel position with respect to the spindle a, as shown in Fig. 6.
While in this parallel position the brake ring d remains unexpanded, and therefore
free to revolve with the spindle a, barrel c and disc f. But upon the withdrawal
of power from the handle h, the load will cause the barrel c to reverse its motion to
a small extent. This motion causes the lever e to assume a diagonal position
relatively to the spindle a, by reason of the inertia of the plate, as shown in
Fig. 7. The plug e then forces the meeting ends of the brake ring d apart, thus
expanding the ring, and causing it to become jammed in the cylinder b, and thereby
to securely hold the load against any further movement, until the spindle a is
again moved in the direction to lift the load; the driver g, being then in immediate
contact with the lug c, moves forward the barrel c, and, restoring the lever e to a
position parallel to the spindle a, as shown in Fig. 6, the brake ring d springs
back and becomes reduced to a smaller diameter, thus leaving the drum c free to
revolve.
с
When lowering the load, the movement of the handle h and spindle a, is reversed.
The load on the barrel c causes the lever e to assume the position shown in Fig. 7,
thereby expanding the brake ring, and preventing the further descent of the load
until, by the further movement of the handle in the reverse direction, the driver g
acts upon the plate f, so as to reduce the inclination of the lever e, and also reduce
the frictional contact of the brake ring, allowing the load to descend with a steady
movement, so long as the spindle is moved in the reverse direction to that of lifting
the load. A chain wheel or rope pulley c, as shown in Figs. 4 and 5 may be
substituted for the winding barrel c, or, where increased power is required,
necessitating a train of gearing, a pinion may be used, as shown in Figs. 1 and 3.
In order to economise space the friction cylinder b may be arranged as shown in
Fig. 8, in which the box bis independent of the bearings, and is prevented from
rotating by means of lugs cast on the box; the staysk which hold the
frames p p in position, passing through the lugs b¹.
c
The brake cylinder may be held by means of an ordinary strap brake, which,
on being released, leaves the cylinder 6 free to revolve, when the load may be
allowed to descend at any desired speed. A chain or rope wheel ¹ (Fig. 8),
belt pulleys or other driving appliances may be substituted for the handle h
(Fig. 6).
In another modification of our invention, we apply it as a friction pulley to
hoisting or other belt-driven machinery, as illustrated by Figs. 9, 10, 11 and 12;
Fig. 9 being a sectional elevation: Fig. 10 a plan view of the expanding ring d
and plug e Fig. 11 being an elevation of the casting and ring ; and Fig. 12
being an end view of the casting 2. In this arrangement is a plain cylinder,
having no external projections, but having a prolongation of the central boss, on
which a wheel or pulley m of any suitable size may be fitted, as shown in Fig. 9.
The pulley m is fast on the boss of the friction box b, the latter being free
to revolve on the spindle a, when driven by a belt. c is a casting placed within
the friction box 6 and keyed to the spindle a, having a flange which is embraced by
the expanding ring or strap d, the same being provided with projections d¹ and ²
(Fig. 11) which fit loosely into corresponding slots in the casting x, and which
permits the expansion of the ring d, but causes x and d to rotate together. An
elliptical plug e is fitted in the opening in the ring d, having a single armed lever e
projecting through a slot w in the casting x. The outer end of the lever e is
attached to a sliding sleeve g¹, by a short connecting arm or link r.
The sleeve g¹
slides on a feather key secured to the spindle a. On pressing the sleeve g¹ towards
the casting x, the link becomes nearly parallel to the face of the casting .
T
:
The

page_text: Twi
lever a is thereby moved from a parallel poligonal position, the ring d being
partial of the
The expansion
holds
the several parts firmly together, thereby transmitting motion from a moving to a
stationary body by frictional contact. The inside periphery of a pulley may be
substituted for the shell or box b.
Having now particularly described and ascertained the nature of our said
invention, and in what manner the same is to be performed, we declare that
what we claim is :-
1. In the construction of self-sustaining hoists, the application and use of a
stationary cylindrical projection or box b, as a fixed brake block, in combination with
an expansible brake ring d, a cam plug e' attached to and actuated by a single or
double armed lever e, the ring d being caused to revolve by means of a driver g,
keyed to the spindle a, and caused to expand by means of the lever e, cam plug e¹,
and idle disc f, all severally operating substantially as herein before described and
illustrated by the drawings.
2. The several modifications in the construction of our improved self-sustaining
mechanism for hoists and other lifting appliances, substantially as herein before
described and illustrated by Figs. 1 to 8 of the drawings.
3. The application and use of our improved brake cylinder and other apparatus,
to hoisting or other belt driven machinery, substantially as herein before described
and illustrated by Figs. 9, 10, 11 and 12 of the drawings.
4. The general construction, and the several combinations and arrangements of
parts, forming our invention of an improved frictional self-sustaining apparatus for
hoists and other lifting appliances, friction pullies, and couplings, substantially as
herein before described and illustrated by the drawings.
GEO. DOWNING,
8. Quality Court, London, W.C., Agent for Applicants.