AN IMPROVED SINGLE CHAIN SKIP OR GRAB
Year: 1886

page_text: Date of Application, 2nd Apr., 1886.
Complete Left, 30th Dec., 1886.
Complete Accepted, 1st Feb., 1887.
I, CHARLES EDWARD VERNON 21 St. Andrews Road, Plaistow, Essex, Engineer do
hereby declare the nature of my invention for "AN IMPROVED SINGLE CHAIN SKIP OR
GRAB to be as follows: :-
55
In accordance with my Invention I dispense with the double chains, rollers and
guides, and extra crane gear usually employed and substitute in lieu thereof the
following novel arrangement of parts to allow of the convenient working and
automatic opening and closing by means of a single chain, of skips or grabs such as
are used for instance for lifting and discharging mud, for unloading grain, and for like
and other purposes.
In carrying out my Invention I proceed as follows:-Between the toggle jointed
levers of a skip or grab such as above defined, I dispose a crosshead or transverse bar
having formed in the centre thereof a rectangular boss which latter is cut or otherwise
formed so as to present on the top an inclined or angular surface, the function of which
is hereinafter described. The crane or hoist chain passes through said central boss
or block of the crosshead and has attached at its extremity a counterbalancing weight
below the crosshead. At a pre-arranged height above the latter, the chain aforesaid
is fitted with a button shaped nodule devised to allow of the latter engaging and
disengaging with a compound-slotted shackle connected with the four corners of the
skip, on the one side of the latter by chains, and on the opposite side by stiff links or
rods; the slotted aperture in the shackle aforesaid being of a pear-like con-
figuration.
When the skip is closed, the shackle aforesaid rests on the inclined top surface of the
central boss or block of the crosshead; and, the smaller end of the slotted aperture in
the shackle will be presented to the direct vertical line which the crane or hoist chain
assumes when the skip is charged. In order to fill the skip; on the latter having been
lowered to the desired spot or site, the actuating crane or hoist chain is slackened, upon
which, the strain being relieved owing to the tightening of the chain, the shackle now
falls and presents the larger portion of the pear-shaped slotted aperture therein so as
to allow of the button shaped nodule-on the crane or hoist chain becoming tightened
in lifting the load-to pass freely through the slotted shackle without engaging or
Price 8d11

page_text: coming into contact therewith; and, the crane or hoist chain and the counterbalancing
weight may then be drawn up until the latter engages with the crosshead which now
takes the whole weight of the skip and its contents or load.
To allow of the emptying of the skip, the reverse action to that above described for
filling, takes place. That is to say, the crane or hoist chain is lowered until the nodule
or button-like protuberance aforesaid slides down and passes through the larger portion
of the pear-shaped slotted aperture of the shackle; then, the actuating chain on being
drawn up or tightened, engages with the smaller end of the above referred to aperture,
with the result that the shackle aforesaid is lifted to a height agreeing with the distance
between the button-like protuberance on the chain, above the crosshead aforesaid and
the weight attached to the extreme end of the chain, below the crosshead; in travelling
which distance and through the intervention of the links or rods and chains respectively
herein before referred to as connecting the shackle with the skip, the latter opens out
radially with the lower joint of the of the ordinary toggle jointed levers of the skip.
JAMES STEVENSON,
Gray's Inn Chambers,
20, High Holborn, London, W.C.,
Agent for Applicant.

page_text: I, CHARLES EDWARD VERNON of 21 Saint Andrews Road, Plaistow, Essex, 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 :-
My improvements relate to single chain Skips or Grabs, such as are used for
instance, for lifting and discharging mud, for unloading grain, and for like and other
purposes.
In accordance with my Invention I adopt the following novel device, reference
being had to the accompanying sheet of drawings in which Figure 1 represents the
Skip or Grab in the position it assumes when charged or full ; Figure 2 illustrates a
further development of the movement indicated in Figure 1; Figure 3 is a front
elevational view of the Skip or Grab in the position as indicated at Figure 1.
a,
In carrying out my Invention, I proceed as follows:-Between the toggle jointed
levers A, A¹ of a skip or grab B, B' such as above defined, I dispose a crosshead or
transverse bar G, having in the centre thereof a rectangular boss or block which
latter is cut, or otherwise formed, so as to present on the top, an inclined, or angular
surface, the function of which is hereinafter described. The crane or hoist chain b
passes through said central boss or block of the crosshead, and has attached to its
extremity a counterbalancing weight c below the crosshead. At a prearranged height
above the latter, the chain aforesaid is fitted with a nodule or button shaped protuber-
ance D, a side view of which is shown at Figure 7,-devised to allow of its engaging
and disengaging with a compound slotted shackle E, which is shown in detail to an
enlarged scale Figure 4; Figures 5 and 6 representing the relative positions of the
shackle E when the crane chain b is tightened, or slackened, respectively. The
shackle Ę is connected with the four corners of the skip or grab, on the one side of the
latter by chains d, and on the opposite side by the stiff links or rods d¹; the slotted
aperture g in the shackle aforesaid, is, as will be seen on reference to the plan Figure 4,
of a pear like configuration. When the skip or grab is closed, the shackle E aforesaid,
rests on the inclined top surface of the central boss or block c (Figure 1) of the cross-
head, and the smaller end g¹ of the slotted aperture in the shackle E will then be presented
to the direct vertical line which the crane or hoist chain b assumes when the skip or
grab B, B¹ is charged.
In order to fill the skip or grab ; on the latter having been lowered to the desired
spot or site, the position it will then assume is shown at Figure. 2, the actuating hoist
or crane chain is slackened; the shackle now falls towards the chains d, assuming
a position owing to the intervention of the stiff links dopposite to that which is the
aperture g the skip is full, and presents the larger portion of the pear-shaped slotted
case when therein, as shown in detail Figure 6, so as to allow of the nodule or button
shaped protuberence D on the crane or hoist chain b on becoming tightened in lifting
the load to pass freely through the slotted shackle E without engaging, or coming into

page_text: contact with the narrow part thereof; the crane or hoist chain b, and the counter-
balancing weight C may then be drawn up until the latter engages with the cross head,
which then takes the whole weight of the skip or grab and its contents or load.
-
I To allow of the emptying of the skip or grab the reverse action to that above
described for filling takes place; that is to say: -the crane or hoist chain is lowered
until the nodule, or button like shaped protuberance D aforesaid, slides down, and
passes through the larger portion g" of the pear shaped slotted aperture of the
shackle; then, the actuating chain on being drawn up or tightened, the nodule D
engages with the smaller end g¹ of the above referred to aperture 9, with the
result that the shackle is lifted to a height agreeing with the distance between the
nodule on the chain above the crosshead G aforesaid, and the weight C attached to the
extreme end of the chain b below the said crosshead G; in travelling which distance,
and through the intervention of the links or rods d', and chains d respectively
connecting the shackle E with the skip or grab B, B', the latter opens out radially with
the lower joint of the ordinary toggle jointed levers A, A¹ of the skip or grab B, B¹, to
allow of the discharge of the contents of the latter.
Having now particularly described and ascertained the nature of my said Invention,
and in what manner the same is to be carried out, I declare that what I claim is:-
First. The novel device to allow of the convenient working and automatic opening
and closing of single chain skips or grabs, substantially as herein set forth and described
in the accompanying sheet of drawings.
Second. In connection with the working of single chain skips or grabs, the use of
the nodule D, and compound slotted shackle E, substantially as herein set forth and
shown in the accompanying drawings.
JAMES
STEVENSON,
Gray's Inn Chambers,
20, High Holborn, London, W.C.,
Agent for Applicant.