A SELF-CLAMPING RAIL CHAIR
Year: 1884

page_text: We JOHN PETER JACKSON and RICHARD SYMONS, both of Savile Street Foundry
Sheffield in the County of York, Engineers, do hereby declare the nature of our
Invention for "A SELF-CLAMPING RAIL CHAIR " to be as follows:-
Our invention relates to a construction of chair for rails in such a manner that
the downward pressure of the rail and of such load as may come on it causes it to
be clamped between the jaws of the chair. For this purpose, we make the chair
in two parts; the one part is secured on the sleeper and has a jaw projecting up
from it, and the other part carrying the other jaw, has a base fitted as a tenon to
slide horizontally through a mortice formed in the base of the first mentioned part.
In the mortice and on the tenon are formed inclines in such a manner that, when
the tenon is pressed down, it is caused by the incline to slide forwards and so to
bring its jaw to bear firmly against the rail, which is thus clamped between the
two jaws. For double headed rails, the tenon and mortice may be made without
inclines on their bearing surfaces the inclines being formed on ribs projecting up
from the bases of the jaws, so that the rail in being pressed down between those
inclines causes the jaws to approach towards each other. We prefer to make the
tenon join with a base sufficiently long to extend over the screws or bolts that
hold down the chair, so as to prevent these from being shaken out.
ស
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1004
ABEL & IMRAY,
Agents for the Applicants,
28, Southampton Buildings,
London, W.C.

page_text: .
We, JOHN PETER JACKSON and RICHARD SYMONS both of Savile Street Foundry
Sheffield in the County of York, Engineers do hereby declare the nature of our
invention for "A SELF-CLAMPING RAIL CHAIR
and in what manner the same is
"
to be performed to be particularly described and ascertained in and by the
following statement :-
Our invention relates to a construction of chair for rails in such a manner that
the downward pressure of the rail and of such load as may come on it causes it to
be clamped between the jaws of the chair. For this purpose we make the chair in
two parts; the one part is secured on the sleeper and has a jaw projecting up from
it, and the other part carrying the other jaw, has a base fitted as a tenon to slide
horizontally through a mortice formed in the base of the first mentioned part. In
the mortice and on the tenon are formed inclines in such a manner that, when the
tenon is pressed down, it is caused by the incline to slide forwards and so to bring
its jaws to bear firmly against the rail which is thus clamped between the two
jaws. For double headed rails, the tenon and mortice may be made without
inclines on their bearing surfaces the inclines being formed on ribs projecting
up from the bases of the jaws so that the rail in being pressed down between those
inclines causes the jaws to approach towards each other. We prefer to make 'the
tenon join with a base sufficiently long to extend over the screws or bolts that
hold down the chair so as to prevent them from being shaken out.
The accompanying drawing shews the construction of our improved railway
chair which we prefer to employ. Fig. 1 shews a longitudinal section, Fig. 2 a
cross section and Fig. 3 a plan.
The chair consists of the base A, having one jaw B formed thereon, in which is
a mortice with inclined upper and lower surfaces C and D. Into this mortice
fits the loose tenon E with correspondingly inclined upper and lower surface and
having formed thereon the second jaw F. On the upper surface of the teuon is
formed a seat G for the base of the rail to bear upon. Thus it will be seen that
the downward pressure exerted by the rail and its load upon the tenon will tend
to force this down the incline D, whereby the jaw F will be made to clamp the
rail forcibly against the fixed jaw B.
The base A is by preference made with cheeks H, between which the outer end
of the tenon and its jaw F fit, so as to be securely held in a transverse direction.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed we declare that
what we claim is
Constructing railway chairs of two parts, the one part consisting of the base
with a fixed jaw having a mortice formed through it with inclined surfaces, and

page_text: the other part consisting of a loose jaw having a seat for the rail and a tenon with
inclined surfaces fitting into the mortice of the fixed jaw, so that the downward
pressure of the rail upon the seat of the loose jaw tends to force its tenon down the
incline of the mortice, so as to clamp the rail firmly between the loose and fixed
jaws, substantially as herein described.
ABEL & IMRAY,
Agents for the Applicants,
28, Southampton Buildings,
London, W.C.