Improvements in Apparatus for Compensating Expansion and Contraction of Signal Pulls.
Year: 1889

page_text: Date of Application, 30th Dec., 1889
Complete Specification Left, 29th Sept., 1890-Accepted, 1st Nov., 1890
PROVISIONAL SPECIFICATION.
Improvements in Apparatus for Compensating Expansion and
Contraction of Signal Pulls.
1, JAMES PUNTER of No. 32 Bevington Road North Kensington in the County of
Middlesex, Carpenter do hereby declare the nature of this invention to be as
follows:-
My invention relates to means of compensating the expansion and contraction
to which the wires or wire cords used as signal pulls are subject under changes
of weather. For this purpose, at or near the middle of the length of the pull
which extends from the operating lever to the signal post, I divide the pull, and
attach each part to the opposite ends of a sway beam from the centre of which
hangs a weight. A pin projects from the centre of this sway beam into a vertical or
nearly vertical slot in the side of a column within which the weight is free to
ascend or descend. One edge of this slot is formed with ratchet teeth so shaped
as to engage the pin of the sway beam when it is strained towards that edge.
The pull in passing to and from the sway bean, passes over guide pullies so as
to reach the sway beam in oppositely inclined directions. While the operating
lever lets the one part of the pull be slack while the signal strains the other part,
the pin of the sway beam bears against the side of the slot which is not toothed,
free to ascend or descend giving the
and the weight and sway beam are
necessary tightness to the pull.
But when the lever is moved to strain the part of the pull connected to it, the
pin of the sway beam is made to engage with one or other of the recesses between
the ratchet teeth and it is held there as a fulcrum on which the sway beam turns
communicating the pull to the signal.
Thaind thin 20th dow of Donamber 1889
ABEL & IMRAY,
Agents for the Applicant..
COMPLETE SPECIFICATION.
Improvements in Apparatus for Compensating Expansion and
Contraction of Signal Pulls.
I, JAMES PUNTER of No. 32, Bevington Road, North Kensington, in the County of
Middlesex, Carpenter, 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:-
My invention relates to means of compensating the expansion and contraction
to which the wires or wire cords used as signals pulls are subject under changes
of weather. For this purpose, at or near the middle of the length of the pull
which extends from the operating lever to the signal post, I divide the pull and
attach each part to the opposite ends of a sway beam, from the centre of which
hangs a weight. A pin projects from the centre of this sway beam into a vertical
or nearly vertical slot in the side of a column, within which the weight is free
to ascend or descend. One edge of this slot is formed with ratchet teeth so
shaped as to engage the pin of the sway beam when it is strained towards that
edge. The pull in passing to and from the sway beam passes over guide pullies
so as to reach the sway beam in oppositely inclined directions.
operating lever lets the one part of the pull be slack while the signal strains the
other part, the pin of the sway beam bears against the side of the slot which is
not toothed and the weight and sway beam are free to ascend or descend giving
While the

page_text: the necessary tightness to the pull. But when the lever is moved to strain the
part of the pull connected to it, the pin of the sway beam is made to engage
with one or other of the recesses between the ratchet teeth and it is held there
as a fulcrum on which the sway beam turns communicating the strain of the pull
to the signal.
The accompanying drawings is a side elevation of compensating apparatus
according to my invention. A standard A has at the top two arms carrying guide
pullies B and b, over which pass respectively L the pull from the operating lever in
the signal cabin, and 7 the pull extending to the signal lever which is, as usual,
counterweighted so as to hold the signal up at "danger" unless when it is pulled
down to indicate "safety" by straining the pulls Ll. These pulls are attached to the
opposite ends of a sway beam E which is shorter than the distance between the
pullies Bb so that the pulls are necessarily inclined as shewn towards the centre
pin D of the beam E. From this centre pin hangs a weight G sufficient to take up
the slack of the pulls Ll. On the standard A at each side of the beam E is fixed a
bar C presenting towards the centre pin D ratchet shaped teeth.
While the pull L is slack and the pull is strained by the signal counterweight, the
pin D is drawn towards the smooth edge of A and the beam E can slide freely up or
down to allow for contraction or expansion of the pulls Ll. But when L is strained
for the purpose of lowering the signal, the pin D is drawn into one or another of the
spaces between the teeth of the rack and thus becomes for the time a stationary
fulcrum for the lever E. Instead of attaching the pull to E by an eye and pin as
indicated at O for the attachment at L, I prefer to attach to E by a clip M engaging
in a notch on the under edge of E. Should the pull L break, the weight G would
descend bringing the beam E into a vertical position, so that the clip M would dis-
engage itself leaving the pull 7 free. The lower part of the standard A may be made
in the form of a hollow column within which the weight G may be accommodated, the
arms of the beam E extending through vertical slots along the sides of the column.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed I declare that what J
claim is :-
Apparatus for compensating expansion and contraction of signal pulls, constructed
and operating, substantially as described with reference to the accompanying
drawings.
Dated this 20th dose of
1000
ABEL & IMRAY,
Agents for the Applicant.