IMPROVEMENTS IN WINDLASSES FOR WORKING CHAIN CABLES AND ROPES
Year: 1877

page_text: LETTERS PATENT to William Horatio Harfield, of the Mansion House Buildings,
in the City of London, for the Invention of "IMPROVEMENTS IN WINDLASSES
FOR WORKING CHAIN CABLES AND ROPES."
ealed the 28th August 1877, and dated the 30th June 1877.
PROVISIONAL SPECIFICATION left by the said William Horatio Harfield at
the Office of the Commissioners of Patents on the 30th June 1877.
WILLIAM HORATIO HARFIELD, of the Mansion House Buildings, in the City of
London. "IMPROVEMENTS IN WINDLASSES FOR WORKING CHAIN CABLES AND
Ropes."
This Invention has for its object improvements in windlasses for working chain
cables and ropes.
Upon a horizontal spindle carried by suitable bearings I fix a purchase wheel,
and upon this wheel I mount two sets of nipping lever pawls; one set is placed
above the other with a sufficient space between them to allow of their vibration.
Above the nipping lever pawls is a cross head vibrating on a pin parallel to the
windlass spindle. Upon this cross head on each side of the centre pin are other
pins which carry two links, one of which is jointed to the long arm of one pawl
and the other to the long arm of the other pawl. To the cross head a vibratory
motion is communicated by means of a direct-acting steam engine or by manual
levers; this causes an almost uniform rotary motion of the windlass, because while
one pawl is gripping the wheel and moving it round, the other pawl is moving
freely over the surface in the opposite direction, and yet is ready to grip the wheel
and so continue the rotation directly the first-mentioned pawl has come to the end
of its travel.
The purchase wheel referred to as being fixed to the spindle I make with a boss
on each side, upon which I mount a series of discs which are prevented turning
round by feathers, but can move freely in a lateral direction.
The chain wheels are mounted freely on the windlass spindle, one on each side of
the purchase wheel, and have drums overhanging the bosses on the purchase wheel.
The drums contain other discs alternating with those on the bosses, and these discs
Union CJ1

page_text: can be compressed together by a hand wheel acting upon a screw on the spindle,
and, when compressed together lightly, form an, efficient break; but when firmly
screwed together act as a powerful frictional connector between the chain wheel and
the purchase wheel.
3
In applying steam power to work the windlass, I use a vertical steam cylinder
and connect a piston rod to the windlass cross head by a suitable joint direct, and
without interposing a rotating shaft.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said William Horatio Harfield in the Great Seal Patent Office on the 29th
December 1877.
WILLIAM HORATIO HARFIELD, of the Mansion House Buildings, in the City of
London. IMPROVEMENTS IN WINDLASSES FOR WORKING CHAIN CABLES. AND
ROPES."
"
This Invention has for its object improvements in windlasses for working chain
cables and ropes.
Upon a horizontal spindle carried by suitable bearings I fix a purchase wheel,
and upon this wheel I mount two sets of nipping lever pawls; one set is placed
above the other with a sufficient space between them to allow of their vibration.
Above the nipping lever pawls is a cross head vibrating on a pin parallel to the
windlass spindle. Upon this cross head on each side of the centre pin are other
pins which carry two links, one of which is jointed to the long arm of one pawl.
and the other to the long arm of the other pawl. To the cross head a vibratory
motion is communicated by means of a direct-acting steam engine or by manual
levers;
this causes an almost uniform rotatory motion of the windlass, because while
one pawl is gripping the wheel and moving it round, the other pawl is moving
freely over the surface in the opposite direction, yet is ready to grip the wheel and
so continue the rotation directly the first-mentioned pawl has come to the end of
its travel.
The purchase wheel referred to as being fixed to the spindle I make with a boss
on each side, upon which I mount a series of discs which are prevented turning
round by feathers, but can move freely in a lateral direction.
The chain wheels are mounted freely on the windlass spindle, one on each side of
the purchase wheel, and have drums overhanging the bosses on the purchase wheel.
The drums contain other discs alternating with those on the bosses, and these discs
can be compressed together by a hand wheel acting upon a screw on the spindle,
and, when compressed together lightly, form an efficient break; but when firmly
screwed together act as a powerful frictional connector between the chain wheel and
the purchase wheel.
In applying steam power to work the windlass I use a vertical steam cylinder
and connect a piston rod to the windlass cross head by a suitable joint direct, and
without interposing a rotating shaft.
In order that my said Invention may be most fully understood and readily
carried into effect, I will proceed to describe the Drawings hereunto annexed,

page_text: DESCRIPTION OF THE DRAWINGS.
Figure 1 is an end elevation, Figure 2 is a plan, and Figure 3, a back clevation
of a windlass constructed according to my Invention; Figure 4 is a section along
the spindle, and in this Figure some of the parts are removed.
Upon the horizontal spindle A carried by bearings B, B, there is fixed the
purchase wheel C, and upon this wheel two sets of nipping lever pawls D, E, are
mounted; one set D is placed above the other E, with a clear space between them to
allow of their vibration.
A cross head F vibrating upon a pin G carries other pins H, I, which carry the
links J, K; the link J is jointed to the long arm of the pawl D, and the link K to
the long arm of the other pawl E. To the cross head Fa vibratory motion is
communicated by means of the manual levers L, L, one or both of which can be
used, as may be most convenient. The centres of links and the lengths of nipping
pawl arms are so proportioned that the vibratory motion of the manual levers
causes an almost uniform rotatory motion of the windlass, because when one pawl is
gripping the wheel and moving it round, the other pawl is moving freely over the
surface in the opposite direction, and yet is ready to grip the wheel and so continue
the rotation directly the first-mentioned pawl has come to the end of its travel.
The purchase wheel C keyed to the spindle has a boss on each side C¹, C', upon
which a series of discs M, M, M, are mounted. They are prevented turning round
by feathers M', but can move freely in a lateral direction.
The chain wheels N, N, are mounted freely on the windlass spindle; they have
overhanging drums N¹, N₁, which contain other discs 0, 0, 0, alternating with those
on the bosses. These discs can be compressed together by the hand wheels P, P,
which work upon screw threads cut upon the windlass spindle, and push the chain
wheels towards the purchase wheel, and so compress the discs together, causing the
chain wheels to be held by the friction of the surfaces. When the discs are lightly
pressed together they form an efficient break.
In applying steam power to work the windlass I employ a vertical steam cylinder
and connect the piston rod to the cross head F by a link. The valves are worked
either by a small rotating shaft with an eccentric and slide in the usual manner, or
by a valve acted upon by the steam in the cylinder, or through tappets, as is
common in direct-acting steam pumps. There are drums on the ends of the
windlass spindle for working ropes.
Having thus described the nature of my Invention and the manner of performing
the same, I would have it understood that I claim as my improvements in
windlasses,
First. The arrangement and combination of parts by which the rotatory motion
of the windlass is produced, consisting of the purchase wheel C with two sets of
nipping pawls D and E upon it, connected by links and K with the cross head F,
which vibrates on the pin G parallel to the windlass spindle.
Secondly. The arrangement of and method of compressing together the discs by
hand wheels screwed upon the windlass spindle.
Thirdly. The construction and arrangement of windlasses, substantially as
described, and illustrated by the annexed Drawings.
Fourthly. The application of a steam engine acting directly upon the cross head
without the intervention of rotating parts.
In witness whereof, I, the said William Horatio Harfield, have hereunto set
my hand and seal, this Twenty-eighth day of December, in the year of our
Lord One thousand eight hundred and seventy-seven.
W. H. HARFIELD. (L.S.)