Improvements in Ships' Log Apparatus.
Year: 1892

page_text: Date of Application, 26th Sept., 1892
Complete Specification Left, 25th July, 1893-Accepted, 2nd Sept., 1893
PROVISIONAL SPECIFICATION.
Improvements in Ships' Log Apparatus.
We FRANK SAMUEL PETT of 27 Buckland Avenue, Dover, in the County of
Kent, Master Mariner, and ERNEST WILLIAM PETT, of Dover, Engineer, do
hereby declare the nature of this invention to be as follows:-
This invention for improvements in ships log apparatus relates to that class of
apparatus in which a rotator towed through the water by a cord transmits through
the said cord the rotations produced by its passage through the water to a counter
situated on the taff rail or stern of the vessel and which indicates the speed of the
towing vessel; and consists essentially in so constructing and arranging the
apparatus that the counter can be conveniently placed on the bridge under
the direct observation of the officer in charge and that the rotator shall be
towed through unbroken water. It also consists in an arrangement for preventing
kinking" in the cord.
66
I am aware that several arrangements have been proposed whereby the rotator
towed through still water has been connected to a counter on the bridge so that its
rotations have been indicated on the counter but in all these cases the continuity of the
cord has been broken. The cord connected to the rotator has been connected to some
device rotating in bearings supported by a spar from the side of the vessel, the
said device being connected by flexible shafting or bevel gearing and a cord to the
counter. These arrangements are principally disadvantageous on account of
the difficulty in keeping the device at the spar end oiled, and in examining the
rotator as it is necessary to draw in the device to the side of the ship whereby the
log rotator is liable to be damaged and then to draw in the cord which as
the rotator continues revolving and the other end is fixed becomes entangled.
In a ships log apparatus arranged and constructed according to this invention
the towing cord connecting the rotator to the counter on the bridge or other
convenient place passes through an eyelet ring supported on the end of a spar
projecting from the side of the vessel preferably at such distance astern of the
bridge that the angle formed by the cord at the ring is greater than 135 degrees
so that the rotations of the rotator will be communicated to the counter notwith-
standing the angle of the cord. In order to protect the cord from fraying where it
rotates in contact with the ring it is surrounded at this point by a close spiral
spring which rotates with the cord but can be readily slipped along it. It will be
readily seen that the rotator can be hauled in from the bridge and as soon as it is
seen to be clear or is cleared the log line or cord is slacked away and the counter
takes out any "kinks or turns that may be in the cord or log line.
"
In order to prevent "kinking" of the cord near the rotator due to any relative
forward movement of the rotator (caused by a following sea) or at any other likely
place it is surrounded at this end or place by a close spiral spring rotating with the
cord but free to slide on it. In neither case does the spiral spring act as a flexible
shaft but only so as to protect the end from fraying or from kinking, the log line
taking the towing strain of the rotator.
In a modification the eyelet ring is replaced by a bell-mouthed tube revolving in
bearings provided with rollers or balls or other devices for reducing the friction;
and as the rotator draws the cord through the tube a knot at a convenient point on
it is arranged to engage with a pin in the tube so that the tube rotates with the
cord.
In another modification a spiral spring of sufficient diameter to allow the log line
or cord to be drawn through is attached to the after part of the bell mouth tube.
That part of the Ion line
LC

page_text: mentioned is protected by means of a spiral spring as before described. At the
fore end of the log rotator is attached a spiral spring through which the log line or
cord is rove before being attached to the rotator.
The spar or other projection is supported with suitable stays and guys the inner
end of the spar being provided with a suitable joint so as to attach it to the rail or
ship's deck.
To oil the flexible spiral spring which comes in contact with the eyelet at the
spar end, the line is hauled on to the bridge and that part of the log line that
passes through and is behind the spiral spring is saturated with oil. It is then
slacked away when the towing strain will cause the oil to be squeezed out of the
cord and which will come in contact with the eyelet.
Dated this 26th day of September 1892.
WHEATLEY & MACKENZIE,
40, Chancery Lane, London, W.C., Agents.
COMPLETE SPECIFICATION.
Improvements in Ships' Log Apparatus.
We, FRANK SAMUEL PETT of 27 Buckland Avenue, Dover in the County of
Kent, Master Mariner, and ERNEST WILLIAM PETT of Dover, 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 for improvements in ships log apparatus relates to that class of
apparatus in which a rotator towed through the water by a cord transmits through
the said cord the rotations produced by its passage through the water to a counter
situated on the taff rail or stern of the vessel and which indicates the distance the
towing vessel has travelled and consists essentially in so constructing and arranging
the apparatus that the counter can be conveniently placed on the bridge under the
direct observation of the officer in charge and that the rotator shall be towed
through unbroken water forward of the ships propeller. It also consists in an
arrangement for preventing "kinking" in the cord.
L.
I am aware that several arrangements have been proposed whereby the rotator
towed through still water has been connected to a counter on the bridge so that its
rotations have been indicated on the counter but in all these cases the continuity
of the cord has been broken. The cord connected to the rotator has been
connected to some device rotating in bearings supported by a spar from the side
of the vessel the said device being connected by flexible shafting or bevel gearing
and a cord to the counter. These arrangements are principally disadvantageous on
account of the difficulty in keeping the device at the spar end oiled and of the
danger of damaging the rotator against the side of the ship when the rotator is
hauled in for examination or repairs.
In a ships log apparatus arranged and constructed according to this invention the
towing cord connecting the rotator to the counter on the bridge or other convenient
place passes through a universal hollow bearing-that is, a bearing in which a
hollow shaft through which the log line passes is free to take any angle in its
bearings between determined limits and is free to rotate at that angle-supported
on the end of a spar projecting preferably at right angles from the side of the
vessel and at such distance astern of the bridge that the angle formed by the cord
at the bearing is greater than 135 degrees so that the rotations of the rotator will
be communicated to the counter notwithstanding the angle of the cord. As the
rotator draws the cord through the hollow shaft a knot at a convenient point on
it is arranged to engage with a projection in the shaft so that the shaft rotates
with the cord. It will be readily seen that the rotator can be hauled to the spar
end from the bridge and as soon as it is seen to be clear or is cleared the log line

page_text: "
or cord is slacked away and the counter takes out any "kinks or turns that may
be in the cord or log line.
In order to prevent kinking of the cord near the rotator due to any relative
forward movement of the rotator (caused by a following sea) or in front of the
universal bearing or at any other likely place it is surrounded at this end or
place by a close spiral spring rotating with the cord but free to slide on it.
neither case does the spiral spring act as a flexible shaft but only so as to protect
the end from fraying or from kinking, the log line taking the towing strain of the
rotator.
In
In a modification a spiral spring of sufficient diameter to allow of the log line or
cord being drawn through is attached to the after part of the rotating piece or shaft
or fore end of the log rotator.
The spar or other projection is supported with suitable topping lift and guys, the
inner end of the spar being provided with a suitable joint so as to attach it to the
rail or ships deck.
In the accompanying sheet of illustrative drawings:-
Figure 1 is a section of a part of a ships log apparatus constructed according to
this invention and by means of which the counter can be conveniently placed on the
bridge and the rotator towed at the side of the ship in unbroken water, and Figure 2
is a side elevation of the same.
Figure 3 is an elevation of an arrangement for preventing kinking in the
log line.
The spar A is secured at its inner end to the ships rail by means of the
bracket E of the goose neck joint B; it can thus be rotated in a vertical plane on
the pivot C¹ and in a horizontal plane on the pivot D. The bracket E is secured
to the ships rail by lashing. On the inner end of the spar A is secured a metal
ring F which is free to work in the cap G of the goose neck and is retained
therein by the screws H. It is clamped in position by the wing screw H'. The
outer end of the spar A is fitted with a collared ring J working in a guy block J
supported by suitable topping lift and guys so that the outer end can be swung in
parallel to the ships side. The collared ring J carries at its outer end the ball
bearing L in which works the ball shaft M. One set of balls N is retained in the
bearing by the ring o secured to the bearing by screws P and the other set of
balls N is secured in the cap R by another ring o secured to the cap R by
screws P. The cap R is screwed into the bearing and retained in place by the
screw S. The ball shaft M is provided with a bell mouthed hole X in which are
ribs V. The log line passes from the counter on the bridge through the bell
mouthed hole X to the rotator, a knot being arranged on the line in such position
that when the rotator is in the desired position in the water the knot enters the
bell mouth of the hole X. The spar is slewed round until the axis of the ball
shaft and bearing coincide and is then clamped in this position by the screw H'.
The axis of the ball shaft is free to adapt itself in its bearing to any variation
of the angle of the log line. The bearing is oiled by means of a tube W extending
from an oil cup on the inner end of the spar along the spar to the bearing as
clearly shewn.
Instead of a knot in the log line, a helical spring Y is placed over the log line
and its ends are received on bushes Z lashed or served to the line, the after lashing
acting in the same manner as the knot and the spring Y, preventing kinking of the
line at this part.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is :-
1. In a ships log apparatus the use of a universal hollow bearing through
which the log line connecting the rotator and counter is passed and in which
it jams when being towed substantially as described for the purpose specified.
2. In a ships log apparatus the use of a hollow ball rotating in ball bearings

page_text: and through which the log line connecting the rotator and counter is passed
and in which it jams when being towed substantially as described for the purpose
specified.
3. In a ships log apparatus the use of a spiral steel spring, surrounding the
log line at bends or other parts liable to kink, to prevent kinking substantially as
described.
4. The improvements in ships log apparatus substantially as described with
reference to the drawings.
Dated this 25th day of July 1893.
WHEATLEY & MACKENZIE,
40, Chancery Lane, London, W.C., Agents.