IMPROVE- MENTS IN CRANES
Year: 1867

page_text: LETTERS PATENT to Robert Duncan, of Partick, in the County of Lanark,
North Britain, Ironfounder and Engineer, for the Invention of "IMPROVE-
MENTS IN CRANES,"
Sealed the 17th September 1867, and dated the 23rd March 1867.
PROVISIONAL SPECIFICATION left by the said Robert Duncan at the
Office of the Commissioners of Patents, with his Petition, on the
28rd March 1867.
I, ROBERT DUNCAN, of Partick, in the County of Lanark, North Britain,
Ironfounder and Engineer, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN CRANES," to be as follows, that is to say:―
This Invention relates to cranes of the kind in which a vertical swivelling
pillar, mast, or upright to which the gib is connected by a joint at the bottom
and by a chain or rods at the top is held in position by two inclined stays placed
In vertical planes at right or other angles to each other; and the features of
novelty in the improved arrangements are, first, the making of one of the stays
with an opening and movable connection so that the gib can be swung over
the space between the stays which has hitherto been unavailable; and, secondly,
and alternatively, the fitting of the crane with two gibs, one to work on one
side of the stays, and the other on the other side.
In practically earrying out the Invention a piece is at it were cut away
from one of the stays sufficient for the gib to pass across; the upper part of

page_text: the divided stay is connected to the other stay by a horizontal tie piece; the
lower part is strengthened by an inclined strut or stay. To the lower part of
the stay there are jointed two levers, one on each side, and shaped at their
upper ends to fit upon tapered dovetailed pieces on the upper part of the stay.
When the gib has to cross the stay one lever is turned to allow the gib to
enter, that lever is then fixed, and the gib is temporarily held between the
two levers; and the other lever is then turned to allow the gib to pass out on
the other side. If the gib is held up by a chain the cap of the swivelling
upright is made hollow for such chain to pass down through it to the barrel.
Rollers may be mounted upon the bottom side of the opening in the stay for
the gib to rest upon when passing through. The details of the arrangements
are obviously susceptible of modification, and in particular various appliances
may be used for connecting the upper and lower parts of the divided stay.
In the alternative arrangement with two gibs a similar tubular construction
of the cap will be required.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Robert Duncan in the Great Seal Patent Office on the
21st September 1867.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ROBERT
DUNCAN, of Partick, in the County of Lanark, North Britain, Ironfounder
and Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-third day of March, in the year of our Lord
One thousand eight hundred and sixty-seven, in the thirtieth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said Robert Duncan, Her special licence that I, the said Robert Duncan, my
executors, administrators, and assigns, or such others as I, the said Robert
Duncan, my executors, administrators, and assigns, should at any time agree
with, and no others, from time to time and at all times thereafter during the
term therein expressed, should and lawfully might make, use, exercise, and
vend, within the United Kingdom of Great Britain and Ireland, the Channel
Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN CRANES," upon
the condition (amongst others) that I, the said Robert Duncan, my executors
or administrators, by an instrument in writing under my, or their, or one of
their hands and seals, should particularly describe and ascertain the nature of
the said Invention, and in what manner the same was to be performed,

page_text: and cause the same to be filed in the Great Seal Patent Office within six
calendar months next and immediately after the date of the said Letters
Patent.
NOW KNOW YE, that I, the said Robert Duncan, do hereby declare the
nature of my said Invention, and in what manner the same is. to be performed,
to be particularly described and ascertained in and by the following statement
in writing, reference being had to the accompanying Drawings, that, is to
Bay:-
My said Invention relates to cranes of the kind in which a vertical swivelling
pillar, mast, or upright, to which the gib is connected by a joint at the bottom,
and by a chain or rods at the top, is held in position by two inclined stays
placed in vertical planes at right or other angles to each other, and the features
of novelty in my improved arrangements are, first, the making of one of the
stays with an opening and movable connections, so that the gib can be swung
over the space between the stays, which space has hitherto been unavailable;
and, secondly, and alternatively, the fitting of the crane with two gibs, one
to work on one side of the stays, and the other on the other side.
And in order that my said Invention and the mauner of performing the
same may be properly understood, I have hereunto appended a Sheet of
explanatory Drawings, to be herein-after referred to, and representing a
derrick crane as constructed with one modification of my improvements.
Figure 1 is an elevation representing the gib 1 as in the act of being passed
across one of the stays 2, 8, whilst the other stay is supposed to be hid by the
swivelling pillar or upright 4. The other Figures represent the details as
enlarged, Figures 2 and 8 being an elevation and vertical section showing the
arrangement of the swivelling cap 5 and pulley 6 at the top of the upright 4;
Figures 4 and 5 are views at right angles to each other of the gate or opening
in the stay 2, 8, with its accompanying details; and Figure 6 is a cross
section, showing the arrangement of safety catches which are employed to
prevent the opening of both sides of the gate at one time.
The various details of the crane that are not concerned in providing for the
passage of the gib across the stay may be made according to any suitable and
approved plan, and parts not referred to herein-after are to be understood as
constructed in the usual way.
In practically carrying out my Invention a piece is as it were cut away
from one, 2, 8, of the stays, the space or gate 7 thus formed being made
sufficient for the gib 1 to pass across. The upper part 3 of the divided stay
may be connected to the other stay by a horizontal tie piece, but this tie piece
is not shown, as I do not now consider that it is required. The lower part 2

page_text: The outer pawl 16
of the stay is strengthened by an inclined strut or stay 8. Two levers 9, 10,
are jointed to the lower part 2 of the stay, one on each side, and upon a pin
or bolt 11 passed through the end of the stay 2, and through strengthening
plates fixed thereon. The lower parts of the levers 9, 10, are of wood, but
the upper parts which close the gate 7 are of iron, and the upper ends are
shaped to fit upon tapered dovetailed pieces 12 of iron fixed upon the upper
stay 8. When the gib 1 has to cross the stay 2, 3, one lever 9 is turned into
the position in which it is shown in Figure 1 to allow the gib to enter the
gate 7; that lever 9 is then fixed across the gate, and the gib 1 is temporarily
held between the two levers 9, 10, and the other lever 10 is then turned to
allow the gib to pass out on the other side. In order to obtain complete
security and safety the bottom end of each lever 9 or 10 is fitted with a metal
plate formed with a lip or flange 13, and with a double ratchet rack 14. The
flange 13 enters under a flange on a plate 15, fixed to the stay 2, and the
rack 14 engages with pawls 16, 17, on each side of it.
has to be raised by hand when the lever is to be opened; the other pawl 17
is on a spindle, which passes through the stay 2, as best seen in Figure 6,
and on which a lever 18 is fixed at the other side, and when the gate lever 10
is closed and in its place on the other side a pin on it holds the pawl lever 18
so as to keep the pawl 17 out of gear. Similar parts 13, 14, 15, 16, 17, 18,
are provided in connection with. both gate levers 9, 10, and the levers 18 may
be covered by plates to prevent their being tampered with, slots being made
in those plates to allow the pins on the gate levers to enter and act upon
them. With these arrangements the opening of either gate lever 9 or 10, by
taking away the pin from supporting the pawl lever 18 on that side causes the
pawl 17 on the other side to engage with the rack on the other gate lever,
and prevent the opening thereof; and this other gate lever can only be
made free to open by the action of closing the one previously open, as it is
necessary for it to be completely closed in order to free the pawl 17 from the
rack 14 of the other lever. If the gib 1 is held up by a chain 19, as indicated,
it is necessary to make the cap 5 of the swivelling upright 4 hollow, as repre-
sented, for the chain to pass down through it to the barrel, and so that the
chain may be clear and free in all positions of the gib.
Rollers may be mounted upon the bottom side of the opening or gate 7 in
the stay 2, 3, for the gib 1 to rest upon when passing through. The details of
the arrangement are obviously susceptible of modification, and in particular
various appliances may be used for connecting the upper and lower parts of
the divided stay 2, 3.
In my improved alternative arrangement with two gibs a similar tubular

page_text: construction of the cap 5 will be required, and the winding arrangements
must of course be in duplicate.
Having thus particularly described my said Invention, and the manner in
which the same is to be performed, I have to state that I do not restrict
myself to the precise details herein described or delineated; but that what
I believe to be novel and original and claim as the Invention secured to me
by the herein-before in part recited Letters Patent is,―
1. The making of one of the stays of cranes of the kind herein-before
described with an opening and movable connections, substantially as herein-
before described.
And, 2. The fitting of such cranes with two gibs.
In witness whereof, I, the said Robert Duncan, have hereunto set my
hand and seal, this Twentieth day of September, in the year of our
Lord One thousand eight hundred and sixty-seven.
5
Witness,
EDMUND HUNT,
Patent Agent,
Glasgow.
ROBERT DUNCAN. (L.8.)