TV THE CONSTD HATIAW AR T
Year: 1870

page_text: LETTERS PATENT to William Erskine Bartlett, of Edinburgh, North
Britain, Assistant Manager to the North British Rubber Company,
for the Invention of "TURDAKOMENTO TV THE CONSTD HATIAW
AR T&STIC
Sealed the 15th November 1870, and dated the 10th September 1870.
PROVISIONAL SPECIFICATION left by the said William Erskine Bartlett
at the Office of the Commissioners of Patents, with his Petition, on
the 10th September 1870.
I, WILLIAM ERSKINE BARTLETT, of Edinburgh, North Britain,
Assistant Manager to the North British Rubber Company, do hereby
declare the nature of the said Invention for "IMPROVEMENTS IN THE CON-
STRUCTION OF ELASTIC TYRES FOR CARRIAGE WHEELS," to be as follows:-
:-
This Invention relates to a novel construction of elastic wheel tyre
which will admit of being more easily and cheaply made than those at
present in use, and can be repaired or replaced in detail, and at much
less cost than continuous elastic tyres. To this end I form the tyre of a

page_text: series of segment-shaped pieces of vulcanized india-rubber, which I fit
between flanges with which the wheel is provided, and I secure the
segments in place by means of transverse rods, which pass through the
segment pieces and through radial slots in the flanges. These rods may
be formed with heads, and they are secured by nuts, which fit on to the
screwed ends of the rods. Between the ends of the india-rubber blocks
or segment pieces and the flanges I insert metal washers (upon the rods)
for the purpose of holding the segment pieces centrally between the
flanges. The sides of these washers next the rubber are convexed, and
the inner angles of the rubber blocks I round off, and I thus provide
space wherein the rubber may expand when compressed by the weight of
the load carried by the wheel. The outer angles of the blocks_may_also_
be rounded, if desired. To allow of the compression of the blocks
agreably through their mass the radial slots in the flanges are provided;
thus when pressure is put upon the blocks these rods instead of
remaining quiescent will recede, and thus the pressure on the blocks
will be evenly distributed through the mass thereof. Outside the tyre
segments, and to protect them from injury from the road, I place a
metal covering consisting of a series of narrow plates linked or bound
together or connected together by a continuous band of leather or india-
rubber similar to ordinary driving bands. This metal covering may be
prevented from moving sideways off the compressible tyre in various
ways; for example, by causing the metal plates to overlap the sides and
to grip the segment pieces.
Instead of the segments being made continuous across the face of the
wheel they may be made shorter, and two or more series may be
employed to get the required width, in which case the metallic coverings
may be made with flanges projecting between these series of segments,
and thus kept from moving off the tyre segments.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said William Erskine Bartlett in the Great Seal Patent
Office on the 10th March 1871.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
ERSKINE BARTLETT, of Edinburgh, North Britain, Assistant Manager of
the North British Rubber Company, send greeting.

page_text: WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Tenth day of September, in the year
of our Lord One thousand eight hundred and seventy, in the thirty-
fourth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said William Erskine Bartlett, Her special
licence that I, the said William Erskine Bartlett, my. exccutors, admiuis-
trators, and assigns, or such others as I, the said William Erskine
Bartlett, my executors, administrators, and 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
"IMPROVEMENTS IN THE CONSTRUCTION OF ELASTIC TYRES FOR CARRIAGE WHEELS,"
upon the condition (amongst others) that I, the said William Erskine
Bartlett, my executors or administrators, by an instrument in writing
under my, or their, or one of their hands and seals, 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 immc-
diately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said William Erskine Bartlett, 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 Drawing hereunto
annexed, and to the letters and figures marked thereon (that is to
say):-
This Invention relates to a novel construction of elastic wheel tyre
which will admit of being more easily and cheaply made than those at
present in use and can be repaired or replaced in detail and at a much
less cost than continuous elastic tyres.
The Invention is applicable mainly to the wheels of traction engines,
but it may be also employed in connection with other wheel carriages
used upon common roads.
In carrying out my Invention I form the elastic tyre of a series of
segment-shaped pieces of vulcanized india-rubber, and fit the same
between flanges with which the sides of the wheel are provided. These
segments I secure in place by means of transverse rods, which pass
through the segment pieces and through radial slots in the flanges.

page_text: Between the ends of the india-rubber blocks or segment pieces and the
flanges I insert metal washers (upon the rods) for the purpose of holding
the segment pieces centrally between the flanges and to leave a space
between the segment pieces and the flanges for the rubber to expand
laterally; and for the like purpose I round off the inner angles of the
rubber blocks, whereby the rubber will yield with. facility to the down-
ward pressure of the weight of the load carried by the wheel. The outer
angles of the blocks may also be rounded, if desired. To allow of the
compression of the blocks equably throughout their mass the radial slots
in the flanges are provided; thus when pressure is put upon the blocks
these rods instead of remaining quiescent will recede and the pressure
on the blocks will be equably distributed through the mass thereof, as
_desired.
In order to protect the tyre segments from injury from the road
I propose to place a metal covering consisting of a series of narrow
plates linked or bound together or connected together by a continuous
band of leather or india-rubber, somewhat after the manner described in
the Specification of J. B. Harris's Patent, dated August the Twelfth, One
thousand eight hundred and seventy.
Instead of the segments being made continuous across the face of the
wheel they may be made shorter, and two or more series, according to
the breadth of wheel to be covered, may be employed to get the required
width. In this case advantage may be taken of the annular space or
spaces between the segment pieces to receive flanges that project from
the inner face of the metallic covering, whereby that covering will be
prevented from moving off the tyre segments.
In the accompanying Drawing Fig. 1 represents a side view of a
portion of a wheel partly in section with my improvements applied
thereto; and Fig. 2 is a cross section of the same taken on the line A, B,
in Fig. 1. In both Figures corresponding parts are marked with corre-
sponding letters.
Wis the rigid wheel tyre, and the wheel flanges furnished with
radial slots S, S, (Fig. 1). These flanges are secured to the wheel
sides ff, by screw bolts D, or in any other convenient manner. On
and round the rigid wheel tyre W are two scries of blocks of vulcanized
india-rubber or other approved elastic compound R made on metal hollow
mandrils m, through which metal pins p are passed. These pins are
made long enough to extend through and beyond the radial slots S, S, in

page_text: the wheel flanges, and they are retained in position by nuts n but so as to.
move radially in said slots when the rubber blocks R are compressed by
the weight of the carriage. The series of rubber blocks R are kept apart
or from lateral movement on the mandrils by metal rings or washers »,
which are of such internal diameter as will permit of their being slidden
over the rigid wheel tyre into any desired position; the rubber blocks R
are also kept at any distance from the wheel flanges f by washers w
passed over the pins p.
To protect the clastic segment blocks R from abrasion or injuries to
which they would be liable if brought into contact with the road a
rubber and canvass band C is applied to the elastic tyre, and faced
outside with treading bars of steel or iron T. These bars are attached by
rivets passing through the band C and through rivetting plates t on
the inner side of the bands. These rivetting plates are bent, as shewn
at k, to form projections extending between the two series of rubber
blocks R, and by means of these projections the band C and the treading
pieces T are kept to the face of the wheel.
Having now set forth the nature of my Invention of "Improvements
in the Construction of Elastic Tyres for Carriage Wheels," and explained
the manner of carrying the same into effect, I wish it to be understood
that under the above in part recited Letters Patent I claim, constructing
elastic tyres in segments and applying them to the rigid tyres of carriage
wheels in the manner and for the purpose above set forth.
In witness whereof, I, the said William Erskine Bartlett, have
hercunto set my hand and seal, the Seventh day of March, in the
year of our Lord One thousand eight hundred and seventy-one.
Witness,
W. FIRTH,
W¼. E. BARTLETT. (L.S.)
Secretary to the North British Rubber Co., Limited,
Castle Mills,
Edinburgh.