Improvements in the Construction of Built-up Cranks.
Year: 1898

page_text: PROVISIONAL SPECIFICATION.
Improvements in the Construction of Built-up Cranks.
1, WILLIAM ROGER DAWE, 82, Andover Street, City of Sheffield, Manager of
Steel Works, do hereby declare the nature of my invention to be as follows:
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The object of this invention is to simplify the construction of built up cranks,
and to render it much easier to separate the several parts, and to substitute a
new part for one which may have been damaged.
In describing a single throw crank, having a neck on each side of the crank,
for example only, I make each cheek or side of the crank in two parts the
division being longitudinal through its width, one part being continuous with
the crank, and the other part being continuous with the neck..
Upon the face of the neck part is a central longitudinal strip or projection,.
and in the face of the crank part is a corresponding longitudinal groove into
which the strip upon the other part fits, and through the two parts when they
are put together, bolts are passed in such a manner that they pass through the
strip and the groove and thus secure the parts together.
In a crank so built, the crank pin with its cheeks can be removed and a new
one inserted without altering its position.
If preferred the strips may be made dovetailed and the grooves undercut, or
when rectangular there may be one or more studs upon the face of the strip
and corresponding recesses made in the slot to receive them, to prevent longi-
tudinal movement, and I may if desired pass a bolt completely through the crank
pin and through the two parts of the divided cheeks.
Dated the 3rd day of November 1898.
ROBT. F. DRURY, C.P.A.,
Agent for Applicant,
Bank Buildings, George Street, Sheffield.
Improvements in the Construction of Built-up Cranks.
I, WILLIAM ROGER DAWE, 82, Andover Street, City of Sheffield, Manager of
Steel Works, 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 the construction or method of building, what are
technically known as "built-up" cranks for steam engines and other purposes;

page_text: the object being to render it easy to separate the several parts, and to substitute
a new part for one which may have been damaged
The invention is illustrated in the annexed drawings, like letters refer to like
parts.
1
Fig. 1, represents a crank built up according to my invention.
Fig. 2, top view of same.
Fig. 3, the two cheeks separated, and section of same through the dotted line.
Fig. 4, represents the crank portion with a section through the dotted lines.
In the application of the invention to a single throw crank such as shown in
the illustration, I make each cheek or side of the crank in two parts the division
being longitudinal, one part A, being made continuous with the shaft T, and the
other part being made continuous with the crank C, and marked B.
Upon the part A, is a central longitudinal rib or projection R, and in the face
of the crank cheek B, is a longitudinal groove G, see Fig. 4, corresponding in
its cross sectional configuration with the rib R, which fits therein.
When the crank portion C, is in position, and its cheek B, is properly engaged
with the parts A and R, of the crank shaft S. bolts D. are passed through bolt-
holes made through both the parts B, and R, by which the parts are firmly
secured together.
In a crank so built up, a damaged crank C, can be removed and a new one
inserted without disturbing the shaft or its bearings.
Although I prefer to make the ribs R, of a dovetailed form, in some cases they
may be made rectangular, and if desired one or more studs may project from
the face and enter corresponding holes made in the face of B, to prevent longi-
tudinal movement; I may also pass a long bolt completely through the crank
pin C, and the side cheeks A, but these are not essentials.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what
I claim, is:
1-The improved construction of built up cranks, as herein before described and
shown.
2-A crank consisting of a centre part C. with cheeks B, provided with central
grooves G, to receive corresponding ribs R, on the cheeks A, of the shafts S, and
secured by bolts D, as herein before described with reference to the annexed
drawings.
Dated the 3rd day of August 1900
ROBT. F. DRURY, C.P.A.,
Agent for Applicant,
Bank Buildings, George Street, Sheffield.