IMPROVE- MENTS IN RAILWAY SIGNALS
Year: 1871

page_text: LETTERS PATENT to Benjamin Bagshaw, of Crewe, in the County
of Chester, Railway Engine Driver, for the Invention of “IMPROVE-
MENTS IN RAILWAY SIGNALS."
PROVISIONAL SPECIFICATION left by the said Benjamin Bagshaw
at the Office of the Commissioners of Patents, with his Petition,
the 12th April 1871.
I, BENJAMIN BAGSHAW, of Crewe, in the County of Chester, Railway
Engine Driver, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN RAILWAY SIGNALS," to be as follows:-
My improvements refer to the wires or other such apparatus through
the medium of which the pointsman or other official works the signals,
and are designed, firstly, to effect a compensation for the expansion or
contraction of the said wires or other such medium. To effect this
I form a hanging loop therein, which carries a weight, and this weight
rises if the wire contracts or falls if it expands. If a rigid wire bo
employed I use a flexible part, a chain for instance, to form the loop.

page_text: I propose to use a pulley for carrying the weight and to connect one
side of the chain to the said pulley by a pin to enable the signals to
be worked, and should the wire or chain break it will slip over the
pulley and the danger signal will be kept on. I also propose to use tho
weight as a counterbalance, there being another weight applied to
the usual lever, and the official is therefore relioved of the force now
required to shift the signals. The slack of the chain, if it occurs, is
taken up by a weight. I also propose to give two or more officials the
command of the signals and to make them subject to each other; for
this purpose
I use an intermediate pulley bearing against a chain on
the wire, and this being raised draws the said wire and operates on the
signals.
I also propose a method of keeping the wires distended and taking
up slack when the signals are put on or off. For this purpose I employ
a chain passing over pullies and to one end of which a weight is
attached. In order to make the chain fast when it is to operate on
the signals I use a key situate in a slot and provided with a recess
through which the chain passes. This recess has a wedge formed side,
which first acts against the chain to get the flat side of a link, and then
binds it to the side of the aforesaid slot.
The improvemcuts above described may be applied to self-acting
signal apparatus.
'
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Benjamin Bagshaw in the Great Seal Patent Office
on the 12th October 1871.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, BENJAMIN
BAGSHAW, of Crewe, in the County of Chester, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date tho Twelfth day of April, in the year of
our Lord One thousand eight hundred and seventy-one, in the thirty-
fourth year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said Benjamin Bagshaw, Her special license
that I; the said Benjamin Bagshaw, my executors, administrators, and
assigns, or such others as I, the said Benjamin Bagshaw, my executors,
administrators, and assigns, should at any time agree with, and no others,

page_text: The above description explains one part of my Invention; in order
however to afford means of communicating the necessary power through
the chain there is attached thereto a stop 11 (see Fig. 2) which arrives
at times against the shackle which carries the pulley 9, and then the
chain cannot be drawn further over the surface of the said pulley 9.
This arrangement will be best explained in the description of the next
part of my Invention, which consists in an arrangement whereby the
signals are worked by weights, and the pointsman is relieved from somo
of the force now required to work them.
This part of my Invention is shewn at Fig. 1 before referred to and
in the side view of the signal post, Fig. 3. The chain 4 is weighted
as already described at 10, passes over guide pullies 12, and from thence
over a pulley 13 mounted upon a lever 14 which turns upon a centre 15,
then over another pulley 16 on the said lever 14 and carries a weight
17 at its end, which weight arrives at times against a sheath through
which the chain passes. The lever 14 is weighted at 18 and is provided
with a rod 19, whigh at its upper end is jointed to an arm 20 which works
the signal board 20*. According to the positions of the parts shown
the lever 3 having been placed in the notch 21 has drawn the chain 4
in the direction of the arrow, and has brought the stop 11 in contact
with the shackle of the pulley 9, and the chain having been prevented.
from being drawn any further over the said pulley 9 has commenced
lifting that pulley, and consequently weight 10. This lifting of the
pulley slackened the part of the chain 4* leaving it free to be drawn in
the direction of the arrow, and this was effected by the weight 17, which
then fell, and by allowing the lever 14 to be taken down by the weight
18 put the signal on, and thus the parts were brought into the positions
shown in the Drawing, and it will be observed that this putting on of
the signal was not effected directly by the pointsman but by the falling
of the weight 18,
It now remains to be seen how the signal is put off. To effect this
the pointsman places the lever 3,in the notch 22 as usual, and the part 4
of the chain is free to move in the direction of the dotted arrow, and
this being the case the weight 10 draws the pulley 9 downward, and
when it has distended the part 4 of the chain it acts by its gravity upon a
the other part 4* thereof, and draws it in the direction of the dotted
arrow. By these means the weight 17 is brought into contact with the

page_text: lever 14, and the weight 10 descending further will cause the said
lever 14 to turn upon its centre and force upward the rod 19, whereby
the signal 20* will be lowered, after which the signal may again be raised
by the means first described. It has been observed that to put on the
signal the weight 18 is liberated so as to effect that object, and it will
now be seen that to put it off the weight 10 is in like manner employed,
and it will also be understood that in putting off the signal the lever 14
is again raised, so as to leave the weight 17 prepared for again raising it
when required. But another advantage arises from the employment of
this part of my Invention. It has been described that when the signal
is off the lever 14 and weight 17 are raised and that the chain 4* is
distended, should the said chain or any part of its connections break, then
the weight 17 will be liberated, and being free to fall will put the signal
on by the means above described.
Another part of my Invention consists in an arrangement whereby
two or more officials at different situations may have command of the
signal, so as to put it on, but to be dependent upon each other for putting
it off. This arrangement is shewn at Figs. 1 and 2 before mentioned.
At 23* is a lever of the usual construction connected at one end by a
chain 24 to a pulley 25 situate beneath the chain 4, which passes under
two guide pullies 26, 27, the said chain being thus drawn upward into
a loop. At 17*, Fig. 3, is the weight previously denoted by 17, it being
in this instance (the signal being up) provided with a longer chain 4
than that before referred to. Suppose the pointsman at A attempts to
lower the signal by passing the lever 23* to the notch 22*, by doing
this he allows the pulley 25 to descend and slacken the chain 4, but
such slackening can only take place to the extent of causing the
weight 17 to pass upwards into the position of 17, and the signal will.
therefore remain on. Suppose, on the other hand, that the pointsman
at B desires to lower the signal, by passing the lever 3 to the notch 22
he will slacken the chain 4, whereby the said chain will be allowed to
be drawn by the weight 10; but in this case also only for such a
distance as will carry the weight 17* to the position of 17, and the signal
will in this case also remain on. It therefore follows that the said.
signal cannot be put down without the joint consent of the two points-.
men or other officials, the weight 17 having to be drawn through a certain
space by each of them. It is otherwise, however, in reference to putting
the signal on when it is down, for then the pulley 25 will be in a lower

page_text: position than that shown; the levers 3, 23*, being in the notches 22, 23*,
and the weight 17* in the position shewn at 17. Under these circum-
stances it is obvious that the official either at A or B can, by turning
the lever 3 or 23*, cause the weight 17* to pass from the lever 14 and
permit the weight 18 to put the signal on. It will thus be seen that
the signal cannot be taken off without the joint action of A and B, but
that it may be put on by either of them separately.
A modification of the mechanical arrangement connected with the
lever 14 is shown at Fig. 4. In this instance the chain 4 passes over a
pulley 28 carried by the signal post 2, and passes through an eye 29
formed on the said lever 14, and against which the weight 17 arrives.
The operation is the same as that above described.
Another improvement, whereby the chain or its equivalent is kept
distended, is shewn at Fig. 5. The usual lever 30 is provided with a
cross arm 31, which carries pullies 32, 33, and over these the chain 4
passes, bearing on its extremity a weight 34. The chain 4 (see the
enlarged detached view, Fig. 7) passes through an eye 35, within which
there is a rod 36 formed with an incline 37. This rod at its upper, end
is provided with a hook 38, which projects over an extended part of the
catch 39, ordinarily employed for passing into the notches 21, 22. The
signal is shown as on, and if it were desired to put it down the lever 30
would have to pass to the notch 22. But it is obvious that no motion
would be communicated to the chain 4 unless it were made fast to the
said lever 30; but the hooked part 38 by resting upon the quadrant 30*
keeps the incline 37 bound between the links of the chain 4, whereby
it becomes locked to the lever 30, and this locking position is maintained
as the hook 38 travels over the quadrant 30*, but when the catch 39
arrives at the notch 22 it falls therein and also the hooked fast 38,
the said notch 22 being made sufficiently wide to receive them both,
and the weight 41 by pulling down the rod 36 frees the chain from the
incline 37; when this has taken place the chain 4 is free to be distended
by the weight 34. This arrangement may be adapted to any usual
signalling apparatus, but the Drawing shews it adapted to the construction
above described.
Fig. 8 shews another modification whereby the chain may be kept
distended, and is designed to take the place of the weight 10. and
apparatus connected therewith. Upon a lever 50 turning on a centre 51

page_text: Filthly. The use for the purpose aforesaid of the rod 36 and incline 37,
Figs. 5 and 6.
In witness whereof, I, the said Benjamin Bagshaw, have hereunto
set my hand and scal, this Eleventh day of October, in the year
of our Lord One thousand eight hundred and seventy-one.
BENJAMIN BAGSHAW. (L.S.)