IMPROVEMENTS IN APPARATUS FOR RAISING AND LOWERING
Year: 1883

page_text: LETTERS PATENT to Jonathan Pickering and Joseph Thompson Pickering of
Stockton on Tees in the County of Durham Mechanical Engineers for an
Invention of IMPROVEMENTS IN APPARATUS FOR RAISING AND LOWERING
PROVISIONAL SPECIFICATION left by the said Jonathan Pickering and
Joseph Thompson Pickering at the Office of the Commissioners of Patents
on the 25th January 1883.
JONATHAN PICKERING and JOSEPH THOMPSON PICKERING of Stockton on Tees
in the County of Durham Mechanical Engineers IMPROVEMENTS IN APPARATUS
FOR RAISING AND LOWERING WEIGHTS."
This invention relates to improvements applicable to cranes, hoists and the like,
for the purpose of acting as an automatic brake or stop, so that whilst the
mechanism can be worked freely in either hoisting or lowering the load is
suspended when the operation ceases. For this purpose we place in the apparatus
a shaft upon which is fixed a drum, and within this drum are two flanges, one of
which is made with plain faces and the other has the face resembling a clutch of
the scroll form, the end of the drum has a corresponding scroll face, which is
fastened to the drum.
The first named plain flange has a tube fixed upon it which runs loosely upon
the shaft, and at the other end of this tube is a ratchet wheel into which a pawl
engages. Fixed to the clutch scroll flange is another tube which runs loosely upon
the first named tube, this tube has fixed upon the outer end a pinion wheel, which
is geared into a spur wheel to give power as desired. The driving and sustaining
mechanism is as follows.
When power is applied to the shaft, the drum end scroll wedges against the
scroll flange, exerting pressure to the plain faced flange, thereby forcing round the
loose tubes which carry both the pinion and ratchet, when however the motion
ceases, then the pawl retains the ratchet wheel binding and securing the flanges in
the same degree as when hoisting, so that the load is suspended. In lowering, the

page_text: pawl still remains fixing the ratchet wheel and plain flange, but by reason of the
scroll or incline being drawn away the load turns the pinion a similar distance,
rotating and wedging the counterpart scroll, and this prevents the weight
descending more rapidly than the motion given to the shaft.
Although we have described the apparatus in the driving and sustaining
mechanism with the compression of two flanges; we do in some cases make the
scroll or wedge action on the periphery of the flange, and cause frictional contact
with the loose tubes.
For quick hoisting the gearing is dispensed with, and a barrel or chain wheel is
substituted for the pinion wheel.
When these improvements are applied to cranes or winches, the handles cannot
fly round against the operator, when raising or lowering weights.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Jonathan Pickering and Joseph Thompson Pickering in the
Great Seal Patent Office on the 25th July 1883.
"
JONATHAN PICKERING and JOSEPH THOMPSON PICKERING of Stockton on Tees
in the County of Durham Mechanical Engineers IMPROVEMENTS IN APPARATUS
FOR RAISING AND LOWERING WEIGHTS."
This invention relates to improvements applicable to cranes, hoists winding
engines and analogous machines, for the purpose of acting as an automatic brake
or stop, so that whilst the mechanism can be worked freely in either hoisting or
lowering, the load is suspended when the operation ceases.
For this purpose we place in the apparatus a shaft a as shewn in Fig: 1. of the
accompanying Drawings, upon which shaft is fixed a drum a'. Within this drum
are two flanges as shewn in Fig 2 one of which is a plain flange as shewn at b, and
the other flange e has the face resembling a scroll form of clutch consisting of
inclined planes-The end of the drum has a corresponding scroll face formed at c
and which is bolted to the drum as shewn.
The first named flange has a tube or sleeve b¹ which runs loosely upon the shaft,
and at the other end of this tube is a ratchet wheel 62. fixed on the sleeve b', into
which ratchet wheel a pawl engages-Fixed to the clutch scroll e is another tube
or sleeve el which runs loosely upon the tube b-this tube has fixed upon the
outer end a pinion wheel d which gears into a Spur wheel as shewn in Fig: 1. to
give power as desired-The ratchet wheel 6' we have shown in the usual manner
we however prefer in some instances-to use a mechanical equivalent for the teeth
and pawl, a nipping lever constructed as follows-The wheel bs Fig: 3 is a smooth
disc surrounded by a loose ring, and within a projecting part of the ring is a
lever f with a concave end fitting the rim of the disc b³-On applying force to b
as in lowering a load, the lever will nip or bite upon the disc, as the lever fat f'
works upon a fixed centre being held there by a bolt in the frame working in a
slotted hole; by this means we obtain a silent equivalent for the ratchet and pawl
device.
Fig: 4 is another elevation showing the lever end view-The driving and
sustaining mechanism is as follows:-When power is applied to the shaft a the
drum end scroll c becomes wedged against the scroll flange e exerting pressure
against the flange b and thereby forcing round the loose tubes b¹ and e¹ which
carry both the pinion and ratchet-When however the motion ceases, the pawl
retains the ratchet wheel, binding and securing the flanges to the same degree as
when hoisting, so that the load is suspended-In lowering the pawl still holds the
ratchet wheel and flange b fixed, but by reason of the scroll or incline being drawn
away the load turns the pinion a similar distance, rotating and wedging the
counterpart scroll and this prevents the weight descending more rapidly than the
motion given to the shaft
Although we have described the apparatus in the driving and sustaining
mechanism with the compression of two flanges we do in some cases make the
scroll or wedge action on tho periphery of the flange, and cause frictional contact
with the loose tubes as shewn in Fig 5-For quick hoisting the gearing may be
dispensed with and a barrel or chain wheel substituted for the pinion wheel as
shown in Fig: 6.
Fig: 1a is an elevation of Fig: 1.

page_text: Fig 9 is an inside face view of the drum cover c shewing the inclines c'. formed
thereon.
Fig: 10 is a section of Fig: 2 on the line x y and Fig: 11. is a section of the
sleeve e', with a face view of the inclines formed on e
Having thus described the nature of our invention and the manner in which
the same is to be performed, we wish to remark that we do limit ourselves to
the precise details herein given, as they may be varied and modified without
departing from the main feature of our invention and we would observe that we
make no claim to the well known parts of the apparatus, which are only shown to
illustrate the mode of applying our improvements, and that we claim,-
1. The improvements, combination, and arrangements of apparatus for raising
and lowering weights substantially as hereinbefore described and shown on the
drawings.
2. The application and adaptation to hoists, cranes, winches, and other winding
machinery, of the arrangement of scroll or inclined surfaces acting as an automatic
brake and the several means and appliances in connection therewith, substantially
as hereinbefore described and shewn on the drawings.
In witness whereof we the said Jonathan Pickering and Joseph Thompson
Pickering have hereunto set our hands and seals the twenty third day of July
in the year of our Lord 1883.
JONATHAN PICKERING (L.S.)
JOSEPH T PICKERING
(Ļ.S.)