Improvements in the Joints of Pitch Chains for Dredger Buckets and other Purposes.
Year: 1886

page_text: Date of Application, 27th Nov., 1886
Complete Left, 19th Aug., 1887.
Complete Accepted, 20th Sept., 1887.
Improvements in the Joints of Pitch Chains for Dredger Buckets
and other Purposes.
I, ALEXANDER MELVILLE CLARK, of the firm of A. M. and Wm. Clark, of 53,
Chancery Lane, in the County of Middlesex, Fellow of the Institute of Patent Agents,
do hereby declare the nature of this Invention a communication to me from abroad
by Julien Lucien Robert, of 21 Rue Turgot, Paris, France, Contractor for Public
Works, to be as follows:
This invention relates to improvements in jointing the links of pitch chains, such
as are used for dredger buckets, and other similar apparatus.
In the specification of former Letters Patent dated June 18th 1884 No. 9157
reference was made to various possible modes of fixing the sleeve used to prevent
wear of the pin or bolt and the present improvements relate to a mode of fixing,
which has been found to be the most preferable in practice.
Reference is to be had to the accompanying drawing forming part of this speci-
fication, in which figure 1 is a side view (the bolt being in section) and figure 2 a
horizontal section taken in the plane of the bolt, of the improved joint, figure 3 shows
the sleeve separately.
The shank of the joint pin or bolt a is made of rectangular section throughout its
entire length and may therefore be cut from a rod of steel or iron of suitable size. It
is shewn of square section, but any other polygonal form, whether regular or not, will
answer the same purpose.
The head may be of any form and rough as it is forged or cast, as in this case
it plays no part in preventing the rotation of the bolt as in the former patent
referred to.
The bolt a passes through a sleeve e of cast steel preferably hardened, truly
cylindrical externally and corresponding internally to the section of the bolt which
fits therein.
This sleeve e corresponds in length to the width of the male link and therefore to
the distance between the two outer or female links between which the sleeve is

page_text: placed as shewn without being recessed therein, as in consequence of the square
section of the bolt, neither it nor the sleeve can turn in the links d.
The square bolt a is secured by a cross pin or cotter e and fits in corresponding
square holes in the eyes of the outer or female links d, which may or may not be lined
with hushes of hardened steel, square externally and internally.
The eye of the male link is lined as described in the former patent referred to,
with a bushing g of hardened steel fixed therein and turning loose upon the sleeve c.
By means of the improved method of jointing the links herein described, the stop
described in the former patent as being formed upon the side of the outer link, next
the head of the bolt is no longer required, whereby the manufacture of said links is
considerably simplified.
DL: 0711
"
1002
A. MELVILLE CLARK.
By A. M. & Wm. Clark,
53, Chancery Lane, London,
Patent Agents.

page_text: COMPLETE SPECIFICATION.
Improvements in the Joints of Pitch Chains for Dredger Buckets
and other Purposes.
1, ALEXANDER MELVILLE CLARK, of the firm of A. M. and Wm. Clark, of
53, Chancery Lane, in the County of Middlesex, Fellow of the Institute of Patent
Agents, do hereby declare the nature of this Invention (a communication to me from
abroad by Julien Lucien Robert of 21 Rue Turgot Paris France, Contractor for
Public Works) and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement.
This Invention relates to improvements in jointing the links of pitch chains such as
are used for dredger buckets and other similar apparatus. In the specification of
former Letters Patent dated June 18th 1884 No. 9157 reference was made to various
possible modes of fixing the sleeve used to prevent wear of the pin or bolt, and the
present improvements relate to a method of fixing which has been found to be the
most preferable in practice.
Reference is to be had to the drawing accompanying my provisional specification in
which figure 1 is a side view (the bolt being in section) and figure 2 a horizontal
section taken in the plane of the bolt, of the improved method of jointing the links.
Figure 3 shews the sleeve separately.
The shank of the joint pin or bolt a is made of rectangular section throughout its
entire length and may therefore be cut from a rod of steel or iron of suitable size.
It is shewn of square section, but any other polygonal form whether regular or not,
will answer the same purpose.
The head may be of any form and rough, as it is forged or cast, as in this case it
plays no part in preventing the rotation of the bolt, as in the former patent
referred to.
The bolt a passes freely through a sleeve c of cast steel preferably hardened, truly
cylindrical externally and corresponding internally to the section of the bolt which
fits therein. The sleeve o corresponds in length to the width of the male link and
therefore to the distance between the two outer or female links d between which the
sleeve is placed as shewn in figure 2, without requiring to be recessed therein, as in
consequence of the square section of the holt, neither it nor the sleeve can turn in the
links d.
The square bolt a is secured by a cross-pin or cotter e and fits in corresponding
square holes in the eyes of the outer or female links & which may or may not be lined
with bushes of hardened steel, square externally and internally.
The eye of the male link is lined as described in the former patent referred to,
with a bushing g of hardened steel fixed therein and turning loose upon the sleeve c.
By the improved method of jointing the links herein described, the stop described
in the former patent as being formed upon the side of the outer link next the head of

page_text: the bolt, is no longer required, which considerably simplifies the manufacture of said
links.
Having now particularly described and ascertained the nature of the said invention,
and in what manner the same is to be performed I declare that what I claim is -
The employment, in connection with the system of jointing the links of pitch
chains for dredger buckets and other similar apparatus forming the subject of former
Letters Patent dated June 18th 1884 No. 9157, of a joint pin or bolt of rectangular
or polygonal section passing through the sleeve c whereby the sleeve is prevented from
turning, as herein before described and represented in the drawings.
Deted this 10th dow of Ancnct 1997
A. MELVILLE CLARK.
By A. M. & Wm. Clark,
53, Chancery Lane, London,
Patent Agents.