IMPROVEMENTS IN THE CONSTRUCTION OF CRANKS
Year: 1885

page_text: PROVISIONAL SPECIFICATION,
We JOHN FRANCIS HALL, of Norbury, Sheffield in the County of York,
Manager of steel works, and JOHN VERITY, of Billing Bank Branley, in the
County of York Engineer do hereby declare the nature of our said invention for
IMPROVEMENTS IN THE CONSTRUCTION OF CRANKS to be as follows:-
Our invention relates to the construction of Cranks of Engine and other Shafts,
the object being to construct them in such a manner that they may be able to
adapt themselves to any irregular movement of the shaft, or the longitudinal
expansion or contraction of the same, or other causes that would injuriously affect
the working of shafts constructed with solid or built-up cranks.
The Cranks in ordinary use for Engines and other purposes are solid and in one
piece with the shaft, or a rigid connection is made by firmly securing the crank-pin
in both webs and so tying the said webs rigidly together.
.
Now in our improvements we make the crank-pin solid or fitted with one of the
webs, the other web is bored out to receive a circular bush, such bush being made
convex on its periphery, and through this the other end of the crank-pin is passed.
The hole into which the aforesaid bush is received, is bored large enough to
admit two ring plates, one fixed and the other adjustable; these are made concave
on their inner surfaces to fit upon the convex bush, when the crank-pin is in
position.
Space is left between the ring-plates to allow the moveable one to be set up or
adjusted by suitable bolts, when the parts become slack.
The circular bush is preferably split or in sections to allow of its being compressed
upon the pin by adjustment of the ring plates.
Instead of two ring plates one may be used, the other concave surface being in
this case formed on the web itself.
By the above described construction of Crank it will be clearly understood that
on account of the crank-pin being capable of movement in one of the webs, it will
readily adapt itself to any irregular movement of the shaft, or the longitudinal
expansion or contraction of the same and this without in any way interfering with
the firmness and strength of shafts provided with such Cranks.
Dan 16th day of January 1885
ROBT F. DRURY,
Agent for the Applicants,

page_text: COMPLETE SPECIFICATION.
We JOHN FRANCIS HALL, of Norbury Sheffield in the County of York
Manager of Steel Works, and JOHN VERITY of Billing Bank, Bramley in the
County of York, Engineer do hereby declare the nature of our invention for
IMPROVEMENTS IN THE CONSTRUCTION OF CRANKS 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 the construction of Cranks or Crank shafts for Engines
and other purposes, the object being (by reason of their peculiar construction) to
enable them to conform to any irregular action or movement of such shafts, such as
would be caused by longitudinal expansion or contraction, strains, or other causes
that would injuriously affect the working of shafts having solid cranks.
And in order that our invention may be clearly understood, we annex a sheet of
drawings, which fully illustrate the construction of our improved adjustable Crank
shaft.
Fig. 1, is a part sectional plan of a Crank made according to our invention.
Fig 2 & 3, are end elevations of same.
Fig. 4, sectional view of ring plate.
Fig. 5, section of pin-eye in the web.
Fig. 6, end elevation of convex bush.
Fig. 7, section of same.
The same letters of reference indicate the same parts in any of the figures.
In carrying out our invention we make the crank-pin E, either solid with, or
fitted securely to one of the webs D, the other web C, is bored out to form a pin-eye,
to receive a circular bush F, such bush being made convex on its periphery F¹, and
through which the outer end of the crank-pin E, is passed,
The eye into which the bush F, is received, is bored out to a suitable depth, and
of sufficient diameter to admit an adjustable ring plate G, which is made concave on
its inner face to fit upon the outer side of the periphery of the convex bush F.
A corresponding concave part H, is provided in the other portion of the eye, which
in conjunction with the beforementioned ring-plate forms a seating to receive the
convex bush F, and allows it to adjust itself as required.
We split the bush F, as shown at I, to allow of it being compressed upon the
crank-pin E, by the adjustment of the moveable ring-plate C, when the parts
become worn and slack, for which movement a space is left at K.
The adjustment is accomplished by means of suitable bolts L.
To increase the elasticity of the bush F, grooves may be made across the periphery
as shown in Fig. 6.
From the foregoing description it will be clearly understood that the crank pin E,
with the convex bush F is free to oscilate within its bearings as well as being
capable of a to-and-fro motion within the bush so as to adapt itself to any irregular
or angular movement of the shaft, whilst such shaft from various causes is revolving
out of the true or straight line.

page_text: Also in the event of any lateral movement of the screw shaft of a steam vessel
through wear or non-adjustment of the thrust block, or of the shaft itself through
expansion or contraction, the crank-pin by moving to or fro in the convex bush,
readily permits of such movement without in any way interfering with the rotary
motion, or with the strength and firmness of shafts provided with such cranks.
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
1st In the construction of adjustable cranks, the use of a circular bush with a
convex periphery, fitting into a corresponding concave bearing, formed partly in the
solid web of the crank, and partly in an adjustable ring-plate for the purpose
specified, and substantially as described and illustrated.
2 The construction of self adjusting cranks, substantially as herein before described
and as illustrated.