Year: 1885

page_text: I, WILLIAM PEARSON STRAWSON, of Stour Works, Stourbridge, Worcestershire,
Chain and Anchor Manufacturer, do hereby declare the nature of this invention to
be as follows:-
My Invention has reference to improvements in the manufacture of those
anchors in which the bottom of the shank is forked to embrace the arm which
latter is pivotted to the shank by a pin passing through the fork and through
the arm.
Examples of such anchors are those commonly known as Porter's or
Trotman's anchors.
The chief object of my Invention is to increase the strength of the said forked
part at the bottom of the shank and further to provide means whereby the end of
the arm when resting against the shank will be prevented from becoming locked
by its springing across the shank through the arm having become loose in the
forked part through wear.
The ordinary method of manufacturing the forked shank of such anchors is to
forge the shank proper and the two jaws for forming the fork each separately and
then to weld a jaw on each side of the bottom end of the shank to form the fork.
Anchors so made are often found to break where the jaws are welded on to the
shank.
According to my Invention I increase the strength of the said forked part by
forming the jaws and the shank together as a single forging thus dispensing with
the operations of welding the jaws on to the shank and among various methods for
attaining this object I prefer to proceed as follows:-I forge the shank with a
roughly shaped rectangular lump of suitable size at its lower end and while in a
heated state I punch a hole centrally through the upper part of the lump so as to
form the bottom of the jaw when finished. I then enlarge the said hole by cutting
away an approximately triangular shaped piece from the lower side thereof and
I then divide the lump downwards from the hole to the bottom part thus forming
the two jaws of the fork which I then open out from each other and finish by
forging to the size and shape required.
In order that the end of the arm when resting against the shank will be
prevented from becoming locked by its springing across the shank through the arm
having become loose in the forked part through wear I form a swell at each of the
opposite sides of the shank where it is touched by the ends of the arm which said
swells the ends of the arm cannot pass to become locked.

page_text: 1
Improvements in the Manufacture of Certain Kinds of Anchors.
I, WILLIAM PEARSON STRAWSON, of Stour Works, Stourbridge, Worcestershire,
Chain and Anchor Manufacturer, 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 has reference to improvements in the manufacture of those
anchors in which the bottom of the shank is forked to embrace the arm which
latter is pivotted to the shank by a pin passing through the fork and through
the arm. Examples of such anchors are those commonly known as Porter's or
Trotman's anchors,
The chief object of my Invention is to increase the strength of the said forked
part at the bottom of the shank and further to provide means whereby the end of
the arm when resting against the shank will be prevented from becoming locked by
its springing across the shank through the arm having become loose in the forked
part through wear.
The ordinary method of manufacturing the forked shank of such anchors is to
forge the shank proper and the two jaws for forming the fork each separately and
then to weld a jaw on each side of the bottom end of the shank to form the fork.
Anchors so made are often found to break where the jaws are welded on to the
shank.
According to my Invention I increase the strength of the said forked part by
forming the jaws and the shank together as a single forging thus dispensing with
the operations of welding the jaws on to the shank and among various methods for
attaining this object I prefer to proceed as follows:-I forge the shank with a
roughly shaped rectangular lump of suitable size at its lower end and while in a
heated state I punch a hole centrally through the upper part of the lump so as to
form the top of the jaw when finished. I then enlarge the said hole by cutting
away an approximately triangular shaped piece from the lower side thereof and
I then divide the lump downwards from the hole to the bottom part thus forming
the two jaws of the fork which I then open out from each other and finish by
forging to the size and shape required.
On the accompanying drawing Fig. 1 represents in front elevation, part side
elevation and sectional plan a partly forged shank having a roughly shaped
rectangular lump at its lower end, according to my Invention, for forming the
forked part to which the arm is pivotted and Figs. 2, 3 and 4 illustrate progressive
stages in the manufacture of the finished fork from the lump illustrated by Fig. 1.
The same letters of reference indicate the same parts in Figs. 1, 2, 3 and 4.
a (see Fig. 1) is a partly formed shank for a "Porter's" or a "Trotman's "
anchor, or for a similar anchor having a forked shank and pivotted arm, having
forged at the bottom, according to my Invention, a roughly shaped rectangular
lump b. While the lump b is in a heated state I punch a hole o centrally through
its upper part (see Fig. 2) so as to form the top of the jaws when finished. The
hole c is then enlarged by cutting away an approximately triangular-shaped piece
from the lower side (see Fig. 3) and the lump is afterwards divided downwards

page_text: along the central dotted line to the bottom so as to form the two jaws b¹, b³, of the
fork which are then opened out from each other and finished by forging to the size
and shape required, as represented by Fig. 4.
By forging the jaws 61, 62, in a piece with the shank a as above described,
instead of forming each of them separately and then welding them thereto, the
fork is strengthened and the jaws are not liable to break off.
It will be evident that the progressive steps which I have described of forming
the jaws b¹, 6, (Fig. 4) from the lump b on the shank a can be modified without
departing from the nature of my Invention.
In order that the end of the arm when resting against the shank will be
prevented from becoming locked by its springing across the shank through the
arm having become loose in the forked part through wear, I form a swell at each
of the opposite sides of the shank, where it is touched by the ends of the arm,
which said swells the ends of the arm cannot pass to become locked.
This part of my Invention is illustrated by Figs. 5 to 10, both inclusive, of
which Fig. 5 is a part front elevation, Fig. 6 is a part side elevation and Fig. 7
a part sectional plan of a Porter's anchor having swells formed on the shank
according to my Invention; Fig. 8 is a part front elevation, Fig. 9 is a part side
elevation and Fig. 10 a part sectional plan of a Porter's anchor having on the
shank a modified form of the swells illustrated by Figs. 6, 7 and 8.
Referring to Figs. 5, 6 and 7. a is the shank of the anchor and d is the arm
pivotted thereto by the pin e. At each opposite side of that part of the shank a
where it is touched by the ends d¹ of the arm d I form a swell f. The swells fare
made of such a width as to form a bearing for the arm ends and when the arm
has worn so loose in the jaws that its ends would, if the swells f were omitted,
become locked by springing across the shank a. Where the arm ends a touch the
swells I prefer to provide recesses g with inclined sides into which the arm
ends d will loosely fit and be more effectually prevented from moving sideways.
I sometimes make the swells fon two opposite sides only of the shank a as
illustrated by Figs. 8, 9 and 10 instead of on four sides and make the recesses g
below the general level of the side of the shank.
My Invention can be applied to a Trotman's or other similar anchors similarly
as above described and illustrated with reference to a Porter's anchor.
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 improvements in the manufacture of the forked end of the shank of
Porter's, Trotman's and other similar anchors herein described with reference to
Figs. 2, 3 and 4 of the accompanying drawing, that is to say, forming the jaws of
the forked end.and the shank together as a single forging substantially as herein
described and illustrated.
2nd Forming swells on the shank of a Porter's, Trotman's or other similar anchor
and a recess for each end of the arm so as to prevent the arm springing across the
shank substantially as herein described and illustrated by Figs. 5, 6, 7, 8, 9 and 10
of the accompanying drawing.