IMPROVEMENTS IN RAILWAY CHAIRS AND FASTENINGS
Year: 1858

page_text: LETTERS PATENT to Robert Henry Bow, of Edinburgh, in the County
of Mid Lothian, North Britain, Civil Engineer, for the Invention-of
"IMPROVEMENTS IN RAILWAY CHAIRS AND FASTENINGS."
Sealed the 12th May 1859, and dated the 1st December 1858.
PROVISIONAL SPECIFICATION left by the said Robert Henry Bow at.
the Office of the Commissioners of Patents, with his Petition, on the
1st December 1858.
I, ROBERT HENRY Bow, of Edinburgh, in the County of Mid Lothian,
North Britain, Civil Engineer, do hereby declare the nature of my said
Invention for "IMPROVEMENTS IN RAILWAY CHAIRS AND FASTENINGS," to be as
follows, that is to say:-
This Invention relates to an arrangement of railway chair wherein the rail
is held securely in its proper position by three dead or fixed resisting surfaces,
the retaining pressure upon which is brought into play by a fourth pres-
sure, arising from the action of a binding wedge or key, or by a screw or
other fastener. The three dead pressures or fixed resistances are those of
the pressure of the bottom of the rail upon the sole of the chair; the centre
of the web of the rail against the top of the inner and lower jaw of the chair;
and, finally, the pressure of the outer side of the upper flange of the rail
against the outer and higher jaw of the chair. These three pressures are
brought into action by the pressure of a wooden or other key, of circular or
other transverse section, fitting into and pressing against a corresponding con-

page_text: cavity in the interior of the higher jaw of the chair on one side, and on the
other against the outer side of the rail at the part where the lower side of the
web joins the bottom flange. When the key or other binding and adjusting
agent is driven into its place, the pressure exerted by it binds the rail against
the three resisting surfaces of the chair, and holds it tight. The chairs them-
selves generally resemble the common form, but the inner jaw is only about
half the height of the outer one, and the latter is formed with a shallow con-
cavity running horizontally along its central portion. Instead of wood, an iron
key, wedge, or screw may be used for holding the rail. When a screw is used
it may either be tapped directly through the higher jaw of the chair, or work
in a nut let into the chair at an angle of about 45 degrees. The inner end of
the screw bears against the rail through the medium of a spring, which may
be variously placed for the purpose of securing an elastic holding action. This
system is applicable to various sections of rails.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Robert Henry Bow in the Great Seal Patent Office on
the 31st May 1859.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ROBERT
HENRY BOW, of Edinburgh, in the County of Mid Lothian, North Britain,
Civil Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the First day of December, in the year of our Lord
One thousand eight hundred and fifty-eight, in the twenty-second year
of Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said Robert Henry Bow, Her special license that I, the said
Robert Henry Bow, my executors, administrators, and assigns, or such
others as I, the said Robert Henry Bow, my executors, administrators,
or 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 RAILWAY CHAIRS AND FASTENINGS," upon, the
condition (amongst others) that I, the said Robert Henry Bow, by an instru-
ment in writing under my hand, and seal, 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

page_text: Office within six calendar months next and immediately after the date of the
said Letters Patent.
NOW KNOW YE, that I, the said Robert Henry Bow, 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 accompanying Drawings,
and to the letters and figures marked thereon, that is to say:
My said Invention relates to an arrangement of railway chair wherein the
rail is held securely in its proper position by three dead or fixed resisting
surfaces, the retaining pressure upon which is brought into play by a fourth
pressure, arising from the action of a binding wedge or key, or by a screw or
other fastener. The three dead pressures or fixed resistances are those of the
pressure of the bottom of the rail upon the sole of the chair; the centre of the
web of the rail against the top of the inner and lower jaw of the chair; and,
finally, the pressure of the outer side of the upper flange of the rail against the
outer and higher jaw of the chair. These three pressures are brought into
action by the pressure of a wooden or other key, of circular or other trans-
verse section, fitting into and pressing against a corresponding concavity in the
interior of the higher jaw of the chair on one side, and on the other against
the outer side of the rail at the point where the lower side of the web joins the
bottom flange. When the key or other binding and adjusting agent is driven
into its place the pressure exerted by it binds the rail against the three
resisting surfaces of the chair, and holds it tight. The chairs themselves
generally resemble the common form, but the inner jaw is only about half the
height of the outer one, and the latter is formed with a shallow concavity
running horizontally along its central portion. Instead of wood, an iron key;
wedge, or screw may be used for holding the rail. When a screw is used it
may either be tapped directly through the higher jaw of the chair, or work in
a nut let into the chair at an angle of about 45 degrees. The inner end of
the screw bears against the rail through the medium of a spring, which may
be variously placed for the purpose of securing an elastic holding action. This
system is applicable to various sections of rails.
And in order that my said Invention may be properly understood, I shall
now proceed to describe the several illustrative Figures on the explanatory
Sheet of Drawings which I have hereunto appended for the purpose of
showing certain modifications under which my improvements in railway chairs
and fastenings may be judiciously carried out in practice, that is to say:-
Figure 1 on the accompanying Sheet of Drawings is a vertical section of
an ordinary rail, intended to illustrate the direction of the mechanical forces

page_text: that operate upon the rail when in use upon a line of railway; Figure 2 is a
vertical section of one modification of my improved railway chair and wooden
key; Figure 3 is a portion of a transverse section taken in the angular
direction indicated by the dotted line a, b, in Figure 2; Figure 4 is an end
view of the chair; and Figure 5 is a plan çorresponding to Figure 2; Figure 6
is a partially sectional elevation of an improved railway chair in which a screw
is used as a-fastener for the rail in lieu of the improved wooden key shewn in
Figure 2; Figure 7 is a partially sectional elevation of another arrangement
of the screw fastener; Figure 8 is an elevation showing a metallic spring
fastener or key applied in lieu of the wooden key for securing the rail;
Figures 9 and 10 are partially sectional elevations, showing two improved
forms of rails, which are specially adapted to my modifications in railway
chairs.
The principle upon which those modifications of my improved chair shown
in Figures 2, 6, 7, 9, and 10 are constructed, is illustrated in Figure 1 on the
accompanying Drawings, in which the rail A is maintained in a vertical
position by its pressure against the inner surface of the chair; this pressure.
acts in three directions, as indicated by the arrows B, C, and D. The pressure
of the rail in the directions indicated is produced or brought into action by a
fourth pressure, that of the key in the diagonal direction indicated by the
arrow E. The pressure of the key upon the rail is resolved in two directions,
vertically and horizontally; the downward or vertical pressure tending to keep
the rail down firmly on the sole of the chair, whilst the horizontal or inward
pressure is balanced by the pressure B of the upper flange of the rail against the
outer jaw of the chair, which pressure acts in an opposite direction, tending to
turn the rail round the point C as a fulcrum. These forces are constant, but
the rail is also subjected to the action of two variable or intermittent pressures;
the first, arising from the weight of the passing wheel, acts in a vertical
direction, and is indicated by the dotted arrow F; the second force is
produced by the pressure of the flange of the wheel acting against the inner
side of the rail, and is counteracted or balanced by the pressure of the outer
jaw of the chair against the rail in the direction of the arrow B. When these
two forces F and G are brought into play, they serve only to increase the
pressures in the directions of the arrows D and B; the tightness of the rail is
therefore increased instead of being diminished, as in the ordinary arrange-
ments.
One modification of an improved railway chair in which the advantages
lerein-before briefly pointed out are obtained is shown in Figures 2 to 5 of
the accompanying Drawings. The sole or bearing surface H upon which the

page_text: rail rests is flat, or deviates very little therefrom; from this flat surface the
inner jaw I springs, forming an arched or inwardly curved figure, which is
clearly shown in the sectional view Figure 2. The outer jaw J of the chair
rises for a short distance in a vertical direction, and is then curved inwards
over the sole of the chair, terminating in a short vertical part, against the
inner face of which the flange of the rail A presses; the rail A is simply
dropped into the cavity of the chair in the ordinary manner, and rests firmly
and fairly upon the sole of the chair. The vertical position of the rail being
maintained by the lateral pressure of the jaws I and J, the inner jaw is made
so as to meet the rail at about the centre of the web, whilst the outer jaw J
is carried up nearly level with the upper face of the rail, thus affording the
most effectual support to the rail on both sides. The rail arranged in this
simple manner is adapted to meet all the requirements of the ordinary traffic,
since the vertical and lateral pressure of the wheel upon the rail is amply
provided for by the arrangement of the jaws of the chair, the opposing
pressures of which prevent the rail from deviating seriously from the vertical
position. But with a view of keeping the rail constantly and firmly pressed'
up against the surfaces of the jaws I and J, in order to prevent the slightest
rattle or vibration during the passage of the fastest or heaviest trains, a
wooden key K is in this modification driven in between the curved over-
banging part of the outer jaw J and the rail A. The key K is simply a
cylindrical piece of wood, the diameter of which corresponds to the distance
between the curved part of the jaw J and the curve between the web and the
lower flange of the rail A. The key K is driven in between the chair and the
rail, and acts merely as a wedge to prevent any trifling vibration of the rail;
the stability of the rail depending solely upon the peculiar construction of the.
chair, irrespective of the presence or absence of the key.
According to the present mode of constructing railway chairs, the safety.of
the train depends upon the wooden keys being in their places, since, if they
are not so, the rail will overturn, and the locomotive will either leave the line,
or be overthrown. If, however, several keys were absent from the improved
chairs herein-before described, the rails would be securely held in the vertical.
position by the jaws of the chairs, and no accident or inconvenience would.
arise therefrom. The outer jaw J of the chain, although made sufficiently.
high to afford a firm support to the rail under all circumstances, is yet kept
low enough to avoid interfering with the wheels of the carriages when the'
rail becomes worn; so that when the rails are required to be inverted, in
order to present a new face for the traffic, the inversion of the rail is effected
with the same facility as with the ordinary chairs; the only difference being,

page_text: that with the rearrangement the rail is a little lower than before, arising from
the worn part resting upon the sole or bearing surface H. But, on the other
hand, the rearrangement is incomparably superior to the old system, as the
rail in its inverted position is as firm as ever, which, with the present form of
chair is never the case; and the vibration being once set up, it goes on
rapidly increasing and diminishing in a proportionate degree the stability of
the permanent way. A peculiarity in the curvature of the overhanging part
of the jaw J may be here adverted to; this consists in making the curve of the.
part L, Figure 2, of somewhat larger radius than that of the periphery of the
key K, so that when the key is driven in, it is flattened to some extent against
this part, and acts more effectually as a wedge. Instead of using cylindrical
wooden keys in all cases, metal fasteners for preventing the vibration of the
rail may be substituted therefor.
In Figures 6 to 8 on the accompanying Drawings are shown three modifica-
tions of metallic keys. In Figure 6 the modification consists of a screw M,
which works through the angular part N of the outer jaw J of the chair. The
outer extremity or head 0 of the screw M is squared, so that it may be turned
readily by means of a spanner or key. The inner end of the key bears
against a bent piece of steel P, which acts as a spring, and presses against the
shoulder of the rail A. With this arrangement the rail A may be pressed
with any required amount of force against the contiguous faces of the jaws I
and J of the chair. With the exception that the jaw J of the chair is
modified to adapt it to the screw arrangement of fastener, the other parts of
the chair are essentially the same as those herein-before described in reference
to Figures 2 to 5. In the modification shown in Figure 7 of the accom-
panying Drawings the screw M works through the nut Q, which is let into
the chair, an elastic washer R being interposed between the two surfaces to
impart a slight degree of elasticity to the parts. In the modification shown
in Figure 8 of the accompanying Drawings the rail A is shown arranged in a
modified form of the improved chair. In this arrangement the outer jaw J of
the rail is carried upwards in a vertical direction, the upper and lower flanges
of the rail pressing against the vertical face of the jaw, whilst the inner jaw I
is curved inwards to form. a bearing to receive the key S. The fastener or
key for this form of chair may be made either of metal or wood; if the former
material be used, the key, by preference, consists of an elastic ring S, the
diameter of which when expanded is a little larger than the curvature of the
shoulder of the rail and that of the jaw I of the chair. When the key is
driven in, it contracts slightly, its expansive force serving to press the rail A
steadily against the face of the jaw J, an accurately fitting bearing being at

page_text: the same time obtained for the key. If wood is preferred as the material for
the keys, they are made at the upper part of a rectangular figure, as indicated
by the dotted line T, that is to say, the key is cylindrical at the parts that fit
the jaw I and the shoulder of the rail, and at the part T the corner is left on;
so that the key bears against the web of the rail up as high as the line T. In
some cases I prefer to make the outer jaw J of the chair with a swell or
projection on the inner face, as indicated by the dotted line U; this projecting
part is made to curve over and fit the lower flange of the rail, and it serves
to hold the rail down upon its seat, and prevent it overturning should the
key be absent.
In Figures 9 and 10 are shown two modifications of my improved chairs
adapted for rails different from those herein-before referred to. In Figure 9
the rail V is made with a single bearing surface, the lower face where it rests
upon the sole of the chair being made a little wider than the web. The inner
jaw I is slightly curved, and extends upwards above the centre of the web,
whilst the outer jaw is curved inwards from the sole of the chain to afford a
large bearing surface for the key K, the flange of the rail pressing against the
vertical face of the upper part of the jaw. In the arrangement shown in
Figure 10 the chain is modified to suit the particular form of rail therein
delineated. The rail W in this instance is made vertical on the inner side,
the bearing flange extending outwards and wholly upon that side of the rail;
the lower part is also made with a flange, which fits a portion of the periphery
of the key K. The inner jaw I of the chair is made nearly vertical, and the
outer jaw curved to receive the key K, the curvature at the part L being made
to correspond to the periphery of the key K. With trifling modifications
these improved chairs may be adapted to other forms of rails than those
shown in the accompanying Drawings.
Having now described and particularly ascertained the nature of my said
Invention, and the manner in which the same is or may be used or carried
into effect, I may observe, in conclusion, that I do not confine or restrict
myself to the precise details or arrangements which I have had occasion to
describe or refer to, as many variations may be made therefrom without
deviating from the principles or main features of my Invention; but what
I consider to be novel and original, and therefore claim as the Invention
secured to me by the herein-before in part recited Letters Patent, is,―
First, the general arrangement and construction of railway chairs and
fastenings, as herein-before described and shown in the accompanying
Drawings.
:
Second, the system or mode of arranging and constructing railway chairs

page_text: and fastenings whereby the rail is held in position by three dead or fixed
resisting surfaces, the retaining pressure upon which is brought into play by a
fourth pressure produced by any convenient fastener, as herein-before
described.
Third, the system or mode of arranging and constructing railway chairs in
which the rail is maintained in a vertical position by the peculiar arrangement
of the jaws of the chair, which serve to keep the rail erect by their lateral
pressure upon the web and flange of the rail, and without depending upon the
key, as herein-before described, and shewn in the accompanying Drawings, or
any mere modifications of the said arrangements.
Fourth, the system or mode of fastening or tightening the rails in the chairs
to prevent vibration by means of the several arrangements of keys or
fastenings herein-before described, and delineated in the accompanying Draw-
ings, or any mere modification of the said arrangements.
Fifth, the arrangement and construction of chairs for railways adapted to
the forms of rails delineated in Figures 9 and 10 of the accompanying
Drawings, or any mere modification of the rails, as herein-before described.
In witness whereof, I, the said Robert Henry Bow, have hereunto set my
hand and seal, this Twenty-eighth day of May, One thousand eight
hundred and fifty-nine.
ROBERT HENRY BOW.
(L.S.)