IMPROVEMENTS IN SINGLE CHAIN BUCKETS AND GRABS FOR DREDGING, EXCAVATING AND GRAIN ELEVATING PURPOSES
Year: 1885

page_text: GEORGE HIND of 9 Berkley Terrace Convent Lane Hull in the county of York
Engineer practial do hereby declare the nature of my invention for IMPROVEMENTS
IN SINGLE CHAIN BUCKETS AND GRABS FOR DREDGING, EXCAVATING AND GRAIN
ELEVATING PURPOSES to be as follows: —
This
My invention relates to an apparatus by the means of which I am able to lower
fill lift and discharge buckets and grabs, or any similar self filling or discharging
instruments by means of one chain and under the controle of one man.
apparatus is more espicialy designed to be applied to buckets and grabs used in
dredging, excavating and elevating mud sand shingle grain and other similar
material.
The apparatus consists of an outer casing cast in halves and having two side
flanges foining when bolted together a slot on each side in which are jointed two
suspended claws B B up the centre of this casing slides freeley a tube C having at
its lower end a flange and and at its upper part a swell on each side which slides
freely in the slot formed by the flanges in which are jointed the claws B B.
Their is a projection inside the upper end of casing A which is intended to reduce
the diameter sufficient to allow the hoisting chain to pass freely through, and is
for the purpose of protecting the pipe C from the action of the chain. It will be
seen that the claws B B have a swell about onethird their length from the top,
these are to enable the projections on pipe C on its ascending or decending to force
out the claws B B, but when the pipe is either at the top or the bottom of its
travel the claws fall close in by their own weight.
Mounted on the top of casing are two strong shackles for the purpose of
connecting the above arrangement with a central link, which is again connected
to a single light ordinary chain which passes over a sheave fitted in the jib head of
the crane and thence to a small barrel fitted with a hand wheel and forming a
break, placed in a convenent position on foot plate of crane, or winch to be
immediatly under the controle of the attendant.
In combination with the above and by means of a horse shoe shaped bracket G·
securely bolted to the opening slide bar H of bucket or grab and having three
bosses placed at a suitable angle to receive the ends of three sliding steel rods FFF

page_text: which work freely through the top of outer frame K, is mounted a duble flange
peice D and D1 the lower flange D1 in which are drilled holes at a suitable angle
to receive the three slide rods F F F, the upper flange D is rounded over the top to
fit the hollow flange C 1, and is hollowed out underneath to receive the book ends
of claws B B to which it is intended they should engage when it is required to
open the bucket or grab.
Jointed on the under side of cross bar H of bucket or grab are two cranked
leaver L L with their return or catch at the upper end which are intended to
engage with the two shackles OO which are securely riveted or bolted to the
upper portion of outer frame K, the leavers L L are weighted at their outer end in
order that when the hoisting chain is lowered out and the bucket or grab is
suspended in claws B B by gripping the flange D, the levers L L fall close in and
embrace the shackles O O. the raidus rods M M with their rollers M1 and which
embrace the closing chains N N of the bucket or grab their object is to steady the
levers L L in their closed possition in order that they may embrace tightley the
shackles O O while lifting slowly on the hoisting chain, in this case the bucket will
be secured open, when by lowering gentley the bucket is at once liberated from
the claws B B the bucket or grab is then suspended open in the hoisting chain
and is ready to descend for a load as will be seen on referance to Fig 2 in the
accompanying drawing. Fig 6 is a side view of the apparatus and the top portion
of frame K with barrels R and T.
It will be seen that the closing chains N rolling on or off barrels R R will be
drawn tight, the upper end of these chains N are secured to the levers L L by
means of a shackle or a large link through a hole I drilled at an angle of say 65°
to the levers axis, suposing the bucket to have been lowered to the material to be
lifted, the whole weight of the bucket would be pressing on the clams or frames
and forceing the sliding cross bar H tightly up aginst the top of outer frame K, in
this case it will be seen on refferance to the possition of levers L the closing chains N
when drawn tight while in the act of closing bucket by means of the hoisting chain
which is rolled round the opposite way on barrel T to chains N the levers L will
be drawn out and allow the bucket or grab to close.
[It might be said that this action would repeat itself when in the act of lifting
the bucket to clear the claws B B, but this is not the case as the weight applied to
these closing chains N N before the whole weight of bucket or grab is taken is not
more then one third what it is when the bucket is in the act of closing into
material to be lifted.]
When the hoisting chain is lifted slowly the levers L instantly seize the
shackles OO the levers being steadied in an upright possition by the radius rods M
and rollers M 1.
To work the bucket or grabs by means of this apparatus supposing the bucket to
have been lifted with its load and over the place of discharge the flange D engages
and pressers upwards flange C1 which forceses pipe C to ascend to the top of its
travel when the claws B B at once fall inwards then by a sharp motion upwards
to the extent of 14 inches applied by the attendant. to the hand wheel attached to
barrel forming the break, will cause the claws B B to seize the flange D as shown
in the front elevation Fig 1, the flange D suspended in the claws B B, remains
stationary while lowering on the hoisting chain E the bucket at once opens and
discharges its load, at this point the levers L L at once fall into the shackles O O
and by lifting on the hoisting chain slightly and then lowering slowly about
4 inches the bucket is found in the possition as shown at Fig 2 suspended in the
hoisting chain and descending open for its next load, after which the same
opperation can be repeated. Hithertoo it as been found to be a long opperation to
alter the hights at which these single chain buckets or grabs grabs may be opened
and suspended, it will at once be seen that more or less length must be applied
to the suspended arrangement in order that they may be discharged at varius
hights. This difficulty is entirely overcome in my arrangement as it will be readily
understood that the attendent may instantly alter the hight where he stands and

page_text: at his pleasure. It as also been found a difficulty in all single chain buckets or
grabs to liberate them should they grab a pile or tree stump while dredging in a
river or in any possition under water where piles have been driven. This difficulty
is also overcome by this apparatus as it will at once be seen that the attendent
may instantly run the caseing A carrying the claws B B down the hoisting chain
when they will at once engage with the flange D then by keeping these tight by
means of the hand wheel and hoisting slowly with the crane chain will at once
liberate the grab from the pile or tree stump. The head hight is a consideraton
when excavating or elevating by these buckets or grabs the well known duble
chain grabs of a ton capacity will discharge in a hight of about ten feet 6 inches
from underside of jib head sheaves and this is the least hight that any buckets of
this capacity have been made to discharge in.
By this apparatus I am able to discharge within eleven feet from underneath
the jib head sheaves. But against this loss of a few inches in hight I get every
other advantage that is got from the dubl chain system, at the same time dispence
with the wear and tear and noise of a second chain, pitch chains, weights or
winches driven from the engines for the purpois of taking up this second chain
or large links or special flanged balls &c shut in the hoisting chain.

page_text: COMPLETE SPECIFICATION.
GEORGE HIND of 9 Berkley Terrace, Convent Lane, Hull in the County of
York Engineer Practical do hereby declare the nature of my invention for
IMPROVEMENTS IN SINGLE CHAIN BUCKETS AND GRABS and in what manner the
same is to be performed, to be particularly described and ascertained in and by
the following statement:-
My invention relates to an apparatus by the means of which I am able to lower,
fill, lift and discharge buckets and grabs or any similar self-filling and discharging.
instruments by means of one chain and under the control of one man.
This apparatus is more especially designed to be applied to buckets and grabs
used in dredging, excavating and elevating mud, sand, shingle, grain or any similar
material.
The apparatus consists of an outer casing, cast in halves, and having two side
Hanges, forming when bolted together, a slot, on each side, in which are jointed two
suspended claws.
Up the centre of this casing slides freely a tube having at its lower end a hollow
flange, and at its upper part a swell on each side, which slides freely in the slots
formed by the flanges in which are jointed the claws B. B.
There is a projection inside the upper end of casing A which is intended to
reduce the diameter sufficient to allow the hoisting chain E to pass freely through,
and is for the purpose of protecting the tube C from the action of the chain while
working.
It will be seen that the claws B B have a swell, about one-third their length,
from the top. These are to enable the projections on tube C, on its ascending or
descending, to force out the claws B B; but, when the tube is either at the top or
bottom of its travel the claws B B fall close in by their own weight.
Mounted on the top of casing A are two shackles; these are for the purpose of
connecting the above arrangement with a central link which is again connected to
a single light ordinary chain, which passes over a sheave fitted in the jib head of
the crane and thence to a small barrel fitted with a handwheel and forming
a special brake placed in a convenient position on foot-plate of crane or winch to
be immediately under the control of attendant.
It will be seen on reference to the accompanying drawings Fig. 7. and 8 that
the brake consists of a small barrel X fitted with a disc U being cast with handles V
forming a hand-wheel. This disc is cast with a T grove around its front next the
lever W to allow the T bolt Z to slide freely round, when the wing nut is
loosened back and when it is required to alter the height at which the bucket or
grab may be discharged or suspended open in the claws B B in casing A which is
again suspended by small chain P, which passes down jib direct to barrel X. The
lever W is secured to disc U by means of the bolt Z. The disc is also secured to
the barrel X and it will be seen that the whole can revolve freely on a pin between
the bracket.
Cast on the lower portion of bracket is a projection, lettered Y which comes
in direct contact with the lower end of lever W and forms the stop or brake to

page_text: chain P; there is also a pall on the pulling side of barrel X which is only required
to be used when it is necessary to liberate the grab from a tree stump or the top of
an old pile which it may have seized. As a modification of the above brake
arrangement any contrivance having leverage and forming a radius attached to
chain P on footplate of crane would give the required motion to the suspended
claws B B in casing A; but would not so. readily allow of altering the height at
which the grabs may be discharged.
In combination with the above and by means of a horse-shoe shaped bracket
securely bolted to the opening slide bar of bucket or grab and having three bosses
placed at a suitable angle to receive the ends of three sliding steel rods F, F, F,
which work freely through the top of outer frame K, is mounted a double flange
piece D and D1 the lower flange D1 in which are drilled holes at a suitable angle
to receive the three slide rods F, F, F. The upper flange is rounded over the top
to fit the bollow flange C1 and is hollowed out underneath to receive the hook
ends of claws B B; to which it is intended they should engage when it is required
to open out the clams of bucket or grab.
Jointed on the under side of crossbar H of bucket or grab are two cranked
levers L L with their returns or catch at the upper end; which are intended to
engage with the two shackles O, O; these shackles being securely riveted or bolted
to the upper portion of outer frame K, the levers L are weighted at their outer end
in order that when the hoisting chain is lowered out and the bucket or grab is
suspended in claws B B by gripping the flange D the levers L, L, fall close in and
embrace the shackles O, O. The radius rods M, M, with their rollers M 1 embrace
the closing chains N, N of the bucket or grab. The object of these rollers through
the tightening of the closing chains N, N is to steady the levers L, L in their
closed position in order that they may embrace tightly the shackles O, O, while
lifting slowly on the hoisting chain; in this case the bucket or grab will be secured
open, when by lowering gently the bucket is at once liberated from the claws B, B.
The bucket or grab is then suspended open in the hoisting chain and is ready to
descend for the next load.
The application of this apparatus and its operation will more readily be under-
stood on reference to the accompanying drawings.
Fig. 1, is a front elevation of a bucket, having been lifted for the purpose of
being opened out. The rounded flange D on the bucket ascending has pressed up
the hollow flange C1, when the claws B B fall inwards and by a sharp motion
upwards applied to chain P by means of the hand lever W the claws B, B at once
seize the flange D, as shown; then by lowering on the crane chain E it allows the
frame K to descend, when it is found in the position as shown in Fig, 6.
Fig, 6 is a side elevation suspended in the claws B, B with the bucket half open.
This view also shows the action of the closing chain N on the levers L L. When
the bucket or grab is either in the act of opening or closing they are drawn into
this position by the closing chains N N tightening while in the act of rolling on or
off barrel R.
Fig, 2, is also a side elevation of a bucket showing it, in the act of descending
open. It will be seen that the levers LL have fallen into the closed position and seized
the shackles OO. The bucket is therefore suspended open in the hoisting chain E.
At the top of this view may be seen the jib head sheaves. Over sheave S is
suspended the small chain P; to which is connected casing A, sliding tube C and
claws B B.
Fig. 3. is a plan of casing A.
Fig, 4, is a plan of top of grab frame K, and showing the flanges D and D 1, and
the holes to receive the ends of slide rods F F F.
Fig. 5 is a plan of sliding cross bar H. G is the bracket which is bolted to cross
bar H. The three holes are to receive the lower ends of rods F. F F. There are
also the levers L L with their weighted ends L 1. Also, the radius rods M and,
their rollers M 1. They have already been described,
.1

page_text: Referring again to the closing chains N N rolling on or off barrels R R it will
be seen that they must be drawn tight. The upper ends of these chains N N are
connected to levers L L by means of shackles or large links through a hole I,
and I is drilled drilled at an angle of about 65° to the levers axis. That is, the
hole I remains at this angle while the levers L L are in their perpendicular
position as shown at L and L1 in Fig 2.
Supposing the bucket to have been lowered to the material to be lifted the whole
weight of the bucket would be pressing on the clams or frames and forcing the
sliding cross bar H tightly up against the top of the outer frame K. It will readily
be understood on referring to the position of levers L L. The closing chains N N
when drawn tight while in the act of closing bucket by means of the hoisting
chain which is rolled round the opposite way on barrel T to the chains N N on
barrels R. R.
The levers L L will be drawn out clear of shackles OO and allow the bucket or
grab to close into the material.
[It might be said that this action would repeat itself by the levers L L when in
the act of lifting the bucket to clear the claws B B. But this is not the case. The
strain applied to these closing chains N N before the whole weight of bucket or
grab is taken by the hoisting chain E is not more than onethird of what it is when
the bucket is in the act of closing into material to be lifted.]
Therefore when the hoisting chain E is lifted slowly the levers L L instantly
seize the shackles O O, the levers being steadied in their perpendicular position by
the radius rods M and their rollers M 1.
To work these buckets or grabs by means of this apparatus supposing the
bucket to have been lifted with its load and over the place of discharge the
flange D engages and presses upwards flange C1 which forces tube C to ascend to
the top of its travel when the claws B B at once fall inwards; then a sharp motion
applied to break lever W will cause claws B B to rise quickly to the extent of
1 inches through the chain P which is wound round brake barrel X, and to seize
the flange D as shown in the front elevation Fig 1.
The flange D suspended in the claws B B remains stationary while lowering on
the hoisting chain E. The bucket at once opens and discharges its load and when
the clams are fully opened the levers L L at once fall into the shackles O O. Then
by lifting on the hoisting chain E slightly and then lowering slowly about four
inches the bucket is found in the position as shown in drawing Fig. 2. suspended
open in the hoisting chain and descending for its next load; after which the same
operation may be repeated.
Hitherto it has been found to be a long operation to alter the heights at which
these single chain buckets or grabs may be opened and suspended. It will at once
be seen that more or less length must be applied to the arrangement suspended
from the jib head in order that the grab may be discharged at various heights.
This difficulty is entirely overcome in my arrangement as it will be readily
understood that the attendant may easily alter the height instantly where he
stands and at his pleasure.
It has also been found a difficulty in all single chain buckets and grabs to
liberate them should they grab a pile or tree stump while dredging in a river or in
any position under water where piles have been driven.
This difficulty is also overcome by this apparatus as it will at once be seen that
the attendant may instantly run dawn the casing A in which are suspended
claws B B, when they will at once engage with the flange D. Then by means of
lever W, and the pall through the chain P, and hoisting on the crane chain E it
will at once be seen that the grab will be liberated from the pile or tree stump.
The head height is a consideration when excavating or elevating by these
buckets or grabs. The well known double chain grabs of a ton capacity will
discharge in a height of about ten feet six inches from the underside of jib head
sheaves and this is the least space that any buckets or grabs of this capacity have

page_text: been made to discharge in; by my apparatus, I am able to discharge within eleven
feet from underneath the jib head sheaves.
But against this loss of a few inches in head height I get every other advantage
that is got from the double chain system. At the same time I dispense with the
wear and tear and noise of a second chain, pitch chain, heavy balance weights, or
winches driven from the engine for the purpose of taking up this second chain, or
large links, or special flanged balls, et cetera, shut in the hoisting chain.
Having had nearly eight years experience in the construction working and
pushing the double chain system both at home and abroad, I have long seen that
this second chain, constantly running up and down with the grab, was wrong in
principle; causing so much annoyance and loss to those useing them.
Hence my
invention which I hold will remove a very large portion of this trouble and loss to
parties useing these grabs, besides a great saving in the wear and tear of working
parts.
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
First: The combination of a bucket or grab, or any similar self-filling or self-
discharging instruments as herein set forth and described in the accompanying
drawings for dredging, elevating or excavating grain, sand, shingle, mud or any
similar substance, may be raised, suspended, or discharged while suspended, and
lowered open by a single chain under the control of one man.
Secondly: The arrangement as applied to buckets and grabs or any similar
instrument, as casing A, with sliding tube C. and suspended claws B B with the
double flange piece D and D1; casing A with its claws B B suspended from a
sheave by a single chain P allowing casing A through tube C to slide freely up or
down the hoisting chain E; cranked levers L L jointed to cross bar H and their
radius rods M and rollers M 1 and especially the connection and action of closing
chains N N to levers L L at the point I or their equivalent.
Thirdly: In combination with casing A, tube C, claws B B and chain P, the
break, as in drawing, with its disc U, hand-wheel V lever W, stop Y which keeps
the lever W rigid at the moment the flange D is suspended in the claws B B, the
sharp motion given to chain P through the lever W. This form of brake I claim
as essential for lowering and lifting casing A to any required height and to give
the radius required to chain P round barrel X substantially as and for the purpose
set forth.
Fourthly: The arrangement with a grab, bucket or similar instrument, casing A,
tube C or claws B B suspended by a single chain P or their equivalent operated
by means of any radius given through a lever or a wheel-lever L L jointed to
cross-bar H, radius rods AI and rollers M1 and their connecting with closing
chains N N with or without casing A, claws B B or single chain P or their
equivalent. The whole or in part substantially as and for the purposes described.
Dated this 19th den of Ma. 100K