IMPROVEMENTS IN SPIRAL SPRINGS FOR BUFFERS, DRAWBARS, AND OTHER SIMILAR USES
Year: 1884

page_text: We BENJAMIN FREDERICK COCKER, Steel Manufacturer, and JOHN BISHOP
Contractor, both of Nursery Street Wire Mills, Sheffield in the County of York
do hereby declare the nature of our said invention for IMPROVEMENTS IN
SPIRAL SPRINGS FOR BUFFERS, DRAWBARS, AND OTHER SIMILAR USES, to be as
follows:-
Our invention relates to improvements in spiral springs for buffers, drawbars,
and other similar uses, and refers, more particularly to springs made from steel of
a flat section, the object being to cushion the coils of the spring and thus to greatly
reduce the chance of fracture; and it consists in the combination with a spiral
spring as before described, of a layer of indiarubber or othe suitable elastic
material filling or partly filling up the space between the coils of steel...We
prefer that springs for the drawbars of Railway Wagons should have the tapered
ends of the steel forming the last coil, laid close against the next coil so as to form
two complete solid coils this reduces the chance of fracturing the tapered end.
i
We then place a core pin through the centre hole, and after placing the spring
in a suitable mould, force the rubber into the spiral space between the steel.coils,
and afterwise vulcanize it, thus forming a completely cushioned spiral spring.
Dated the Oth dox of Ontahan 1984.

page_text: "
8
COMPLETE SPECIFICATION.
We BENJAMIN FREDERICK COCKER, Steel Manufacturer, and JOHN BISHOP,
Contractor, both of Nursery Street Wire Mills, Sheffield in the County of York
do hereby declare the nature of our invention for IMPROVEMENTS IN SPIRAL
SPRINGS FOR BUFFERS, DRAWBARS, AND OTHER SIMILAR USES and in what
manner the. same is to be performed, to be particularly described and ascertained
in and by the following statement, that is to say :—
Our invention relates to improvements in spiral springs for buffers, drawbars
and other similar uses or purposes, and it refers more particularly to springs made
from steel of a flat section, the object being to cushion the coils of the spring and
thereby greatly reduce the liability to fracture; it consists, in the combination with
a spiral spring (of a flat section of steel as before described) of a layer of india-
rubber or otlier suitable elastic material so placed as to fill up the space between
the coils of steel.
And in order that our invention may be clearly 'understood we have annexed a
sheet of drawings illustrating a spring made according to our invention, and
adapted for the drawbar of a tramcar or similar vehicle. The same letters of
reference indicate the same parts in both the figures.
Fig 1 is a plan of one of our improved springs fitted to the drawbar of a
carriage or car.
•
Fig 2 is a section of same.
A. A are the coils of the steel spring..
B. B. is: the vulcanised rubber.
.C.. C. are thimbles through which the drawbar D is passed, and which retain it
in a central position.
E, is a nut upon the end of drawbar.
iF, is the frame of the carriage or car..
In carrying out our invention.in the construction of a compound spring as used
upon a drawbar for example we make a spiral or coiled spring of steel and of any
desired number of coils A A, after which it is hardened and tempered in the
usual way
T19
We make the tapered ends of the steel forming the outer coils A¹ to lie upon or
close against the next coils which thus act as supports, and protect the tapered
ends from the risk of fracture.
A core pin is then placed in the centre hole of the spring, and by suitable means
rubber is forced into the spiral space between the coils of steel A, in which
position it is submitted to the process of vulcanising, causing it to adhere closely
to the spring.
It is advisable in many cases to surround the spring at a short distance with a
blocking ring so as to limit the action of the spring and prevent undue compression
or cutting of the rubber.

page_text: 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
1 The construction of cushioned spiral or coiled springs, substantially as
hereinbefore described and illustrated.
2-In spiral springs, the method of combining the rubber cushion with the steel
coils and of securing the same, as herein before described and illustrated.
Dated the 8th day of July 1885.
ROB F. DRURY,
Agent for the Applicants.
ROB F. DRURY,
Agent for the Applicants.