IMPROVEMENTS IN FISH-PLATES FOR RAILS
Year: 1876

page_text: PROVISIONAL SPECIFICATION left by Edward Griffith Brewer at the Office
of the Commissioners of Patents on the 22nd May 1876. A communication
from abroad by Hjalmar Bergman, of Stockholm, Sweden, a Captain in the
Corps of Engineers.
EDWARD GRIFFITH BREWER, of Chancery Lane, London. "IMPROVEMENTS IN
FISH-PLATES FOR RAILS." A communication from abroad by Hjalmar Bergman,
of Stockholm, Sweden, a Captain in the Corps of Engineers.
21
12
The object of this Invention is to diminish or do away with the shocks or blows
experienced in travelling on old permanent way of railways, and which act detri-
mentally especially on the rail end and also on the rolling stock. Various "fishing"
appliances have been proposed to do away with this evil but without much success ;
thus may be named amongst others the construction of fish-plates of such a width
that the fisher part of the permanent way is stronger or stiffer than any other part,
but it does not appear to be promising when the cause of the shocks is taken in
account. That the shocks do not proceed directly from the end distance between
the rails or from the depression of the rail ends is tolerably easy to prove, because
the shocks are scarcely or not at all felt in newly laid permanent way with same
distance of rail ends and quite as much elasticity, but in course of a few years (with
ordinary traffic) the shocks become very troublesome. The reason must doubtless
he sought in the foliation or wear near the rail ends, amounting to 1 to 1 of
an inch. This wear must ordinarily always take place so long as the ends are
loaded as much as the other parts of the rail, because the upper parts of the rail at
the end, being there in the form of a beam supported at one end only, have only
half the force of resistance of the intermediate parts, and consequently must be
sooner squeezed down and towards the outside where they do not find any resistance.
This is no doubt the true cause of the shocks, which can only be done away with
by protecting the rail ends against a proportionately too strong load. In the so-
called free or not supported fish-plates this object is to a great extent attained by
the resulting depression of the rail ends and the resulting diminution of the load
and the shock; but the repeated bending down of the ends causes damage to rails
and fish-plates. It has been tried to remove the load to better supported parts by
cutting the rails off slanting at the ends, whereby the foliation is somewhat delayed,
but the slanting ends lose in power of resistance and suffer harder blows because of
the greater distances which the wheels have to jump over.
The shocks will also
take place here, although somewhat later because of the delayed foliation, the whole
width of the slanting surfaces being pressed forward and downward.
[Price 2d.1

page_text: According to this Invention the load on the rail ends is lessened. The outer
plate has the same height as the rail, in order that the wheel tyre in passing may
take its bearing on the said plate also, and thus prevent the rail end from being
pressed down. As the inner part of the tyre is worn hollow by the top of the rail
while the outer part is not worn, the lash-plate or fish must at each end be gently
and slightly sloping in order that the outer part of even the most worn wheel tyre
may meet a sloping surface and no shocks be produced, the wheel running easily
and gently on and off. In order that these slopes he not too steep but yet incline
so far as to be below the most worn out wheel tyre even after a very considerable
wear of the rail top, the last or fish-plates must be much longer than usual, or say
1, to 2 feet. As these fish-plates thus pass on to and rest on the cross sleepers at
this place they possess the advantage that they carry the load better on to thic
sleepers. In order to increase the pressing surface against these sleepers, but chiefly
in order to be able to fasten the fish-plates directly to these sleepers, they are made
with a broad foot or bottom flange resting on the sleepers. They are firmly
fastened thereto by means of inner spike holes and notches for hook spikes outside.
The fish-plate is united to the rails by screwed_bolts passing through holes large
enough to allow for longitudinal expansion. The rails are thus perfectly secure
against every change in position without having to make notches in the bottom
flange for the hook spikes, a point of great importance, especially for steel rails.
If the cost of the addition of the aforesaid broad foot to the fish-plate be con-
sidered out of proportion to the advantages gained the fish-plates may be made
without one or both of them.
1:
In order to prevent the bolt nuts from working loose a thin steel plate is put
underneath each nut. This plate is made with diagonally cut flaps bent up towards
the left upper side of the nut; when its diagonal is vertical this flap is hammered
so that it can feather or spring about / of an inch towards the outside, and
when the nut is turned it keeps the nut from going back, resting with its edge
against one side of the nut, but when turning the nut a quarter turn in the right
direction the flap is depressed by each square corner of same, and jumps up when
the nut stands with its diagonal vertically. When the nut is to be undone the
spanner must be pressed hard against the spring flap, and then the nut can be
turned back over it.