Year: 1886

page_text: I, JOHN HARTNESS of East Boldon in the county of Durham Engineer 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:
This invention relates to certain improvements in anchors and has for its object
to ensure a positive automatic tripping action and to facilitate weighing and
canting, and also to simplify and reduce the cost of manufacture. In anchors of
this class as hitherto constructed the moving tripping head carrying the arms and
flukes has been hinged or pivotted on the shank at its central point or centre of
gravity, its outer line usually being a segment of a circle struck from the centre
of the pivot. By this arrangement the arms do not fall "atrip" with certainty,
but at times may remain in such an upward or other position as to fail to get
a grip, but according to my invention I so form the tripping head and arms as to
dispose its weight in regard to the central pivot about which it oscillates, that any
position of the arms other than the required tripping position is impossible, and
to effect this I place the transverse axis of the arms, that is, the line in or about
which the centre of gravity of the tripping head lies, at some distance behind the
main pivot passing through the shank and this pivot I place as far forward as
possible and thus a positive and constant tripping position of the arms and flukes
at the required angle with the shank is assured, and in order to assist the gripping
power of the arms when the tripping head takes the ground I so construct it that
its outer line is a segment of a circle or circles struck from a centre or centres also
situated behind the main pivot and thus a rotary or crank motion is obtained and
a firm grip is rendered absolutely certain.
The accompanying drawings explain accurately the principle of my invention;
Figures 1 and 3 are plans of anchors the arms being in a position parallel to the
shank, Figures 2 and 4 are elevations with the arms in their norinal position.
The tripping head A and arms B B carrying the flukes b b is preferably made in
one piece, but may be made in two or more pieces rigidly bolted together. It is
hinged on the pivot a secured in the ordinary manner as near as convenient to the
extremity of the shank C which is of usual construction with parallel or fish
bellied sides and provided with the usual shackle c and shank ring if required.
The transverse axis of the arms wx, that is to say, the part of greatest weight in

page_text: which the centre of gravity lies, is situated at a certain distance, which is determined
according to the dimensions and weight of the anchor, behind the pivot a and the
outer line of the tripping head in elevation is preferably struck from a centre also
situated at any point behind and at any distance from a with a radius such as d
or it may be in some cases of an elliptical or eccentric form so that when it takes
the ground and a strain is put on the shank a rotary or crank motion is imparted
to the arms. In plan the outer line may be as shown in the figures or as shown
dotted in figure 1, and the extremities of the outer line are formed with toggles as
shown at a a². A recess is formed in the inner part of the tripping head A of
a form suited to the reception of the shank, and the motion of A thereupon,
and stops a¹ a' are formed therein to bear upon the shank C and limit the
revolution of A to the proper angle on either side of the shank, and also to relieve
undue strain on the arms and pivot a. The arms B may be of any suitable
shape and section such as is shown in figure 1, being found advantageous. When
desired the arms may be set closer together and the pivot a produced and used as
a combined pivot and canting bar as shown in figure 3, the above described
construction and disposition of the weight in regard to the pivot being observed.
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. In the construction of anchors the method of ensuring automatic tripping
action thereof by disposing the centre of gravity of the tripping head behind the
pivot about which it oscillates substantially as and for the purposes described and
illustrated.
2. The hereinbefore described method of ensuring automatic tripping action
combined with the form of tripping head by which crank motion is imparted to
the tripping head when strain is put upon the shank substantially as herein
described and illustrated.
Thin Thnutinth dL. 2006