IMPROVEMENTS IN THE CONSTRUCTION OF CAPSTANS
Year: 1882

page_text: PROVISIONAL SPECIFICATION left by the said Archibald Kennedy at the
Office of the Commissioners of Patents on the 12th May 1882.
"
ARCHIBALD KENNEDY Marquis of Ailsa CERTAIN IMPROVEMENTS IN THE
CONSTRUCTION OF CAPSTANS
First The object of the Invention is to reduce the friction between the block of
the Capstan and the spindle or axle around which such block revolves and
Secondly to the means I employ for giving motion to the Capstan through the
medium of the Capstan bars.
In carrying out the first portion of my invention I form annular spaces in the
Crown and base or other places of the Capstan block around its central axis or
pillar at those parts where the said block would have frictional contact with the
said axis or pillar Into these spaces rollers are placed the axis of which are
parallel with the axis of the central pillar and are so arranged that their
peripheries will bear against the periphery of the central spindle in a manner that
will cause the Capstan when being forced round to exert the least possible friction
at those points upon its supporting axle or pillar where the greatest strain is
exerted thus enabling the Capstan to be worked with a minimum amount of
friction.
Secondly It is usual now to work the Capstan by means of bars inserted into
holes formed in the Capstan block in lieu of which, and according to my invention,
I form a V grooved channel round the upper portion of the Capstan block.and at
a short distance from this groove, and at convenient distances apart studs are
placed which form the fulcra of lever bars, the ends of these bars in contact with
the V groove of the Capstan block have a convex curved formation and are so
arranged that when the bars are being forced in a direction around the central
axis the said curved ends of the Capstan bars will bed against the surface of the
V groove and an abutting pin, which will enable a firm grip or contact to be
maintained between the Capstan and its actuating bars whilst being worked, so as
to revolve round its centre axis or pillar When it is required to reverse the
motion for hauling the abutting pins before mentioned are placed so as to form a
stop on the opposite sides of the Capstan bars.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Archibald Kennedy in the Great Seal Patent Office on the
11th November 1882.
ARCHIBALD KENNEDY Marquis of Ailsa "CERTAIN IMPROVEMENTS IN THE
CONSTRUCTION OF CAPSTANS'
First The object of the Invention is to reduce the friction between the block of
the Capstan and the spindle or axle around which such block revolves and
Secondly to the means I employ for giving motion to the Capstan through the
medium of the Capstan bars.
In carrying out the first portion of my invention I form annular spaces in the
crown and base or other places of the Capstan block around its central axis or
pillar at those points where the said block would have frictional contact with the
said axis or pillar. Into these spaces rollers are placed the axis of which are
parallel with the axis of the central pillar and are so arranged that their peripheries
will bear against the periphery of the central spindle in a manner that will cause
the Capstan when being forced round to exert the least possible friction at those
points upon its supporting axle or pillar where the greatest strain is exerted thus
enabling the Capstan to be worked with a minimum amount of friction
Secondly It is usual now to work the Capstan by means of bars inserted into
holes formed in the Capstan block in lieu of which, and according to my Invention
I form a V grooved channel round the upper portion of the Capstan block and at
a short distance from this groove and at convenient distances apart, studs are
placed which form the fulcra of lever bars, the ends of these bars in contact with
the V groove of the Capstan block have a convex curved formation and are so
arranged that when the bars are being forced in a direction around the central
axis the said curved ends of the Capstan bars will bed against the surface of the
V groove and an abutting pin which will enable a firm grip or contact to be
maintained between the Capstan and its actuating bars whilst being worked so as
to revolve around its central axis or pillar. When it is required to reverse the
motion for hauling, the abutting pins before mentioned are placed so as to form a
stop on the opposite side of the Capstan.
In order that the Invention may be well understood and explained in detail I
have hereunto annexed a sheet of Drawings made on a scale of about three inches
to one foot similar letters of reference being marked on corresponding parts on all
the Figures alike.
DESCRIPTION OF DRAWINGS.
Fig 1. represents in sectional elevation an Eighteen inch Capstan having my
improvements applied thereto; and-
Fig 2. represents a plan view of the Capstan.
In these Figs a is the Capstan block b its central axis or pillar and c the path
or foundational plate on which the Capstan revolves all being old and well known
parts. In carrying out that portion of my Invention relating to the means I
employ for reducing the friction between the central axis or pillar b and the
Capstan block a I proceed as follows:-I form annular spaces d. d. in the crown
and base of the Capstan block around its central axis or pillar bat those places
when the said block would have frictional contact with the said axis or pillar
Into these spaces d, d, rollers e e. are placed in such a position that their peripheries
will bear against the periphery of the central axis or pillar b. in a manner which
will cause the Capstan block a when being forced round to exert the least possible
friction upon its supporting axle or niller where the
montant

page_text: thereby allowing the Capstan to be worked with a minimum amount of exertion
when "breaking ground" or otherwise working against heavy strain.
convex
Secondly The ordinary Capstan bars now employed for working the Capstan
are inserted in holes or recesses formed in the Capstan block to receive them in
lieu of this arrangement and in order to obtain a superior purchase for giving
motion to the said block I proceed as follows:-1 form a V groove or channel f
round the upper portion of the Capstan block and at a short distance from this
groove in the projecting bracket g. g. holes are formed for the reception of the
movable pins h h which form the fulcra of the lever Capstan bars the ends of
these bars in contact with the V groove of the Capstan block have a
curved formation and are so arranged that when the bars i are in position and the
fulcrum pins h h inserted the said curved ends will bed against the V surface of
the block a at a point or points slightly in advance of or behind the central line of
the Capstan and according to the direction in which the Capstan is to be worked
forming thereby a grip upon the Capstan block so long as it is being forced round
its central axis or pillar When it is required to reverse the motion of the Capstan
block for hauling or otherwise the pins hh are removed whilst the bars ii are
reversed so as to bed against the V groove on the opposite side of the central line
when the pins h h are again inserted.
Having now described the nature of my said Invention together with the
manner of performing the same I wish it to be understood that what I claim as
new and as of my Invention is
First The novel arrangement and adaptation to Capstans of the antefrictional
roller marked e. e. in the drawings to be used in the manner and for the
purpose as herein substantially described setforth and fully illustrated in the
drawings annexed.
Secondly The employment use and adaptation to Capstans of the novel form of
Capstan bars marked ii in the drawings to be used in the manner and for
the purpose as herein snbstantially described set forth and fully illustrated in
the Drawings annexed.
In witness whereof I the said Archibald Kennedy Marquis of Ailsa have
hereunto set my hand and seal the Eighth day of November One thousand
eight hundred and eighty two.