Improvements in Chocks for Ships' Boats.
Year: 1898

page_text: Date of Application, 18th Oct., 1898-Accepted, 19th Nov., 1898
CUMPLIFTE SPECIFICATION.
Improvements in Chocks for Ships' Boats.
We, JAMES ROBERTSON, of 50, Ferry Road, Shipwright, and THOMAS BERRY,
A.M.I. Mech. E., of 53, Cowgate, Merchant, both of Dundee, in the County of
Forfar, Scotland, 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 improvements in chocks for ships' boats, the object
being to allow of the boat being cleared for launching in a new and improved
manner and by means of improved apparatus.
And in order that our said invention and the manner of performing or carrying
the same into effect or practice may be properly understood, we have hereunto
appended three explanatory 'sheets of drawings in which the same reference
numerals are used to indicate corresponding parts in all the figures where shown,
that is to say: -
Figure 1, (Sheet 1) is a view looking on the bow of a boat and showing it
resting on the chocks and secured.
Figure 2, (Sheet 1) is a cross-section at A, A, (Figure 1) of a chock.
Figure 3, (Sheet 2) is a similar view to Figure 1, showing the boat clear of
the chocks and in the position it would take when hanging from the davits.
Figures 4, and 5, show respectively in elevation and plan a modified chock.
Figure 6, (Sheet 3) is a section at B, B. (Figure 5) showing the bracket for
the duplex lever and disengaging rods.
Figure 7, (Sheet 5) is a section at C, C, (Figure 5) showing a sliding pin and
its appurtenances.
In carrying out our invention we make each chock 10, in two parts and pivot
them about a common centre by means of a pin 11, so that they can be raised or
lowered the requisite amount. Figures 1, and 2, show a chock in the raised
position and Figures 3, 4, and 5, in the lowered. Each chock consists of blocks
of wood 10, shaped to suit the boat which they are intended to support. Each-
block is carried by two side arms 12, bolts 13, binding each pair of arms_and
their block together. The lower extremities of these arms are mounted on
pins 14, such pins being carried in slots 15, in the bracket 16. The general
arrangement is such that when the pins 14, are closest together the chock is in
the highest position and when furthest away it is fully down and the boat is
unsupported except by the davits. 17, is a locking lever whose purpose is to
keep the pins 14, from sliding away from one another when the boat is on the
chocks. It is pivoted to the one pin and has a slot or slots 18, for receiving the
other pin. In Figures 1, and 2, the lever is shown interlocked with the pin 14.
thus keeping the chock raised to support the boat. In Figures 3, 4, and 5, the
lever is unlocked. 19, are engaging rods, their purpose being to hold the
grips 20, and so keep the boat fast on the chocks. In Figures 1 2, and 3, a
single internal locking lever 17, is used and the engaging rods 19, are open,
these rods moving outwards when the chock is falling but in Figures 4, and 5,
Paine Q71

page_text: a
a duplex external locking lever is used and the engaging rods are crossed and
therefore move in the opposite direction at that time. Figure 1, shows the rods
engaged while Figures 3, 4, and 5, show them. disengaged. When placing
boat on the chocks the operation is as follows. Each chock is raised until the
locking lever 17, engages its pin, care being taken to see that the links 21, are
in position to allow the extremities of the rods 19 to pass through them. The
The
boat is then lowered until its whole weight is supported by the chocks.
grips 20, are then placed in position, lashings 22, binding the extremities of
the grips to the links 21. The suspension ropes are then made taut and fastened
to their respective davits.
Should it be found necessary to clear away the boat, the locking levers 17,
are lifted until the slots 18, clear their pins, whereupon the chocks fall and
the disengaging bolts 19, are withdrawn, leaving the boat swinging on the
davits and the grips clear as shown in Figures 3, or 4. The falling of the chocks
and the withdrawal of the disengaging bolts occur simultaneously and almost
instantaneously.
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:-
(1) In chocks for ships boats the arrangement of parts for simultaneously
clearing the chocks from the boat and the grips from their engaging pins, the
combination consisting of two blocks 10, pivot pin 11, side arms 12, sliding
pins 14, slots 15, bracket 16, locking lever 17, engaging rods 19, and grips 20
substantially as described and illustrated by Figures 1, 2, and 3, of the annexed
drawings.
(2) In chocks for ships boats the arrangement of parts for simultaneously
clearing the chocks from the boat and the grips from their engaging pins, the
combination consisting of two blocks 10, pivot pin 11, side arms 12, sliding
pins 14, slots 15, bracket 16, duplex locking. lever 17, engaging rods 19, and
grips 20, substantially as described and illustrated by Figures 4, 5, 6, and 7,
of the annexed drawings.
Dated this 15th day of October 1898.
GEO. C. DOUGLAS & Co.,
41, Reform Street, Dundee, Agents for Applicants.