Improvements in Railway Chair Keys or Wedges.
Year: 1887

page_text: Date of Application, 30th Nov., 1887
Complete Specification Left, 30th Aug., 1888.
Complete Specification Accepted, 5th Oct., 1888
PROVISIONAL SPECIFICATION.
Improvements in Railway Chair Keys or Wedges.
I, RICHARD MICHELL EASTMAN of 7 Newstead Road, Liverpool, in the County of
Lancaster, Merchant, do hereby declare the nature of this invention to be as
follows
This invention has for its object, a chair key or wedge that shall be adaptable to
existing rails, without extra cost or alteration of the rails or chairs, which shall be
simple of application, which shall fix and tighten up the rail very firmly to the chair,
and which shall not be altered or prejudicially affected by changes of temperature, so
that there will be little or no necessity for that constant watching so requisite in the
case of the ordinary steel wedges.
I form my wedge or key of a single plate of steel rolled or bent into such form as
to give great elasticity, and a bearing either on a large surface of the inside of the
chair, and of the side of the rail, or at least upon two horizontal lines of contact, on
each extending preferably along the entire length of the chair, and beyond it, and
along the opposite face of the rail, and as far removed from each other in vertical
height, as possible. I prefer to forin the key or wedge so that there shall be a scroll
or circular curve of the steel plate pressing against the upper part of the web, and the
lower surface of the upper flange of the rail (if there be an upper flange) and against
the upper inner curve, and top part of the inside of the chair respectively, and another
scroll or circular curve pressing against the bottom curve of the inside of the chair,
and against the lower part of the web, and the upper surface of the lower flange
respectively.
Projections are formed on the key or wedge just beyond the chair on each side,
sloping to nothing at the lateral terminations of the key. These, on the key being
driven home, form little impediment to the driving, but having rectangular inner sides
against the chair prevent all possibility of the key slipping out except when strong
pressure is expressly applied by a special tool to compress the scroll or spring
sufficient to extract it. In place of these two projections, a single projection, fitting

page_text: into a recess in the chair, could be used, but would not be so good. The form of the
key (as will be seen from the above) can be varied considerably, but I prefer for most
purposes, a rectangular plate with the top and bottom edges curled round on the same
side into a scroll, the two scrolls nearly touching each other.
Dated this 29th day of November 1887.
WM. P. THOMPSON & Co.,
Of 6, Lord Street, Liverpool,
Patent Agents for the Applicant.
COMT LEIE SIECIFICATION.
Improvements in Railway Chair Keys or Wedges.
1. RICHARD MICHELL EASTMAN of 7, Newstead Road, Liverpool, in the County of
Lancaster, Merchant, do hereby declare the nature of this invention and in what
manner the same is to be performed, to be particularly described and ascertained in
and by the following statement :-
This invention has for its object, a chair key or wedge that shall be adaptable to
existing rails, without extra cost or alteration of the rails or chairs, which shall be
simple of application, which shall fix and tighten up the rail very firmly to the chair,
and which shall not be altered or prejudicially affected by ordinary changes of
temperature, so that there will be little or no necessity for that constant watching so
requisite in the case of the ordinary wood wedges.
I form my wedge or key of a single plate of steel rolled or bent into such form as
to give great elasticity and a bearing either on a large surface of the inside of the
chair and of the side of the rail, or at least upon two horizontal lines of contact, on
each extending preferably along the entire length of the chair, and beyond it, and
along the opposite face of the rail, and as far removed from each other in vertical
height, as possible. I prefer to form the key or wedge so that there shall be a scroll
or circular curve of the steel plate pressing against the upper part of the web, and the
lower surface of the upper flange of the rail (if there be an upper flange) and against
the upper inner curve, and top part of the inside of the chair respectively, and another
scroll or circular curve pressing against the bottom curve of the inside of the chair,
and against the lower part of the web, and the upper surface of the lower flange
respectively.
The best mode known to me of carrying out my invention is illustrated in the
accompanying drawings in which,
Figure 1 is an elevation of the outside face of wedge.

page_text: Figure 3 is an elevation of the inside face of wedge.
Figure 4 an end elevation, and,
Figure 5 a perspective view showing the wedge in position in a rail chair.
In these A is the rail, B the chair, the key. This key C is formed of a single piece
of steel having its ends formed into scrolls D and E, pressing against the top and
bottom angles of the rail as shown where the heads join on to the web. In order to
prevent the key when once in place from ever working out of position, I press two
indents G and H in the inside of the sheet of steel before curling it, thus forming two
projections on the outer side with sharp approximately parallel faces facing each other.
These faces are rather further apart than the width of the chair.
When therefore the key is compressed and forced into position the two projections
stand out one on each side of the chair, and thus prevent the key from working out of
place. Instead of two projections, a single one fitting a hole or indentation in the
chair near the centre can be used, or the key can be made slightly wedge shaped, and
fit a chair with a side sloping to suit, in which case one projection forced through and
coming against the narrow end of the chair would be the mechanical equivalent of the
above.
Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
1. A railway chair-wedge or key formed of an elastic metallic plate rolled or bent
into such form as to give great elasticity between and a bearing against, both the
chair and the rail at points on each widely apart horizontally, and also widely apart
vertically.
2. In a railway-chair wedge or key formed of elastic metal plate, two projecting
edges pressed or otherwise formed in the plate at such distance apart, that when the
chair is sprung into place these edges will come opposito and close to complementary
edges on the chair, or a mechanical equivalent of this such as described, whereby the
wedge is held securely in the chair.
3. The special form of railway-chair key, or wedge, substantially as described and
illustrated.
Dated this 20th day of Avonst 1000