Year: 1886

page_text: Date of Application, 9th Dec., 1886
Complete Left, 9th Sept., 1887.
Complete Accepted, 11th Oct.. 1887.
We, WILLIAM MATTHEWS of 5 Westminster Chambers, in the City of Westminster
CORNELIUS CORNES and WALTER PITT both of Bath in the County of Somerset,
Engineers, do hereby declare the nature of this invention to be as follows:-
=
In excavating with grabs or excavators especially when sinking wells or foundations
it is often found that the grab or excavators instead of properly entering the ground
merely pares off a thin slice from the hemi-spherical or semi-cylindrical nest or bed
it has made. When sinking a cylinder the effect of this is that the ground is not
properly cut away at the circumference near the bottom of the cylinder which
therefore does not readily sink. The object of this invention is to remove these
objections.
In addition to the ordinary buckets, excavators or tines we employ other tines or
scrapers preferably fixed to them and standing out at an angle from their upper ends
in such a way that when the grab open and the ordinary tines or half buckets are
approximately vertical, the additional tines are approximately horizontal. The action
of closing the grab or excavators causes the additional tines to move about their
axes and thus break up the earth around the hole and carry it down to the outside of
the closed grab to be seized and taken up next time. What may be called a pick
and shovel action is thus obtained.
In order to make the grab or excavator properly enter the ground especially when
additional tines are used, we provide a weight or weights attached to the axis of the
buckets or tines. For grabs to be used for sinking cylinders we make the weight in
the form of a heavy hollow cylinder which carries at its lower end the axis of the
buckets or tines and is prolonged upwards so as to enclose and protect the working
parts of the grab. The weight thus arranged forms a guide which roughly fitting the
cylinder and the hole already sunk tends to keep the grab in a vertical position and
thereby promotes its more efficient action.
1030

page_text: Improvements in Grabs and Excavators.
We, WILLIAM MATTHEWS of
Westminster Chambers in the City of Westminster,
CORNELIUS CORNES and WALTER PITT both of Bath in the County of Somerset,
Engineers, 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 :-
In excavating with grabs or excavators especially when sinking wells or foundations
it is often found that the grab or excavator instead of properly entering the ground
merely pares off a thin slice from the hemi-spherical or semi-cylindrical nest or bed it
has made. When sinking a cylinder the effect of this is that the ground is not
properly cut away at the circumference near the bottom of the cylinder which
therefore does not readily sink. The object of this invention is to remove these
objections.
In addition to the ordinary tines fitted to buckets grabs or excavators we employ
other tines or scrapers preferably fixed to the buckets, grabs or excavators and standing
out at an angle from their upper edges in such a way that when the grab is open and
the ordinary tines are approximately vertical, the additional tines are approximately
horizontal or inclined below the horizontal. The action of closing the grab or
excavators causes the additional tines to move about their axes and thus break up the
earth around the hole and carry it down to the outside of the closed grab to be seized
and taken up next time. What may be called a pick and shovel action is thus
obtained.
In order to make the grab or excavator properly enter the ground especially
when additional tines are used, we provide a weight or weights attached to the
axis of the buckets or tines. For grabs to be used for sinking cylinders we make
the weight in the form of a heavy hollow cylinder which carries at its lower end
the axis of the buckets or tines and is prolonged upwards so as to enclose and
protect the working parts of the grab. The weight thus arranged forms a guide
which roughly fitting the cylinder and the hole already sunk tends to keep the grab
in a vertical position and thereby promotes its more efficient action.
In order that our said invention may be most fully understood and readily carried
into effect we will proceed to describe the drawings hereunto annexed.

page_text: Figure 4 shows one of the jaws in plan together with some other parts.
These figures shew our invention as applied to the apparatus known as Wild's
grab.
AA is a massive iron cylinder carrying at its lower end the axis B on which
the barrel C is able to turn. D D are the jaws or half buckets which carry the
ordinary tines; they are jointed at D₁ D¹ to horns projecting downwards from the
cylinder A. EE are the additional tines or scrapers which, as the jaws D come
together, scrape down the sides of the hole into which the grab and excavator has
been dropped; the material which they so remove from the sides of the hole they
deposit beneath the closed jaws in position to be taken by them after the next drop.
F is a cross head capable of moving up and down in guides within the cylinder A, and
it is connected by links G with the jaws so that, when the cross head is brought to
the upper end of the cylinder A the jaws are separated. On the other hand the
jaws are closed together when the cross head is moved downwards relatively to the
cylinder.
The crane chain H is wound around the barrel Cat C³, and short chains II (of
which portions only are shown) pass from the cross head F to the barrel C and are
wound around it at CC where the diameter is less than at C. The chains II are
wound in the opposite direction to that in which the crane chain H is wound. The
crane chain passes from the barrel C up through the central guide J and through the
tubular piece K which is carried by the cross-head but able to move up and down for
a short distance independently. The piece K carries the hooks or catches L.
M is a loose conical ring which bears against the tails of the catches. N N are dogs
jointed to the cross head and adapted to engage with the crane chain.
This apparatus which constitutes Wild's gearing operates in the following
manner :-
The jaws having closed on the material to be raised the parts occupy the position
in which they are shown in Figure 3, and so the loaded grab and excavator is lifted
by the crane chain. When it has been raised as far as is required for the discharge
of its load, the catches L L pass through a suspended ring which surrounds the
crane chain. The apparatus is then lowered a short distance and the catches engage
with the ring. The apparatus now remains suspended by the catches, the crane chain
being relieved of the load. The cross head descends the short distance which it can
move independently of the catches and the cylinder A descends further until the parts
have assumed the position which they occupy in Figure 2. As the cylinder descends
the jaws of the grab and excavator open and the load previously contained in the
bucket is dropped. During this movement the chains II have been unwound from
the barrel C and thereby the lower end of the crane chain H has been wound upon it.
The apparatus is now again lifted a short distance by the crane chain. The dogs NN
now engage with the chain and prevent it from unwinding from the barrel C. As
soon as the apparatus is lifted clear of the suspended ring and the catches are free,
the cone ring M drops by its own weight throwing the heads of the catches inwards
so that now they can descend through the ring without catching it. The apparatus
is now lowered and the open jaws penetrate into the soil to be excavated. The
crane chain is now slack and the dogs N N are made to release it by the descent of
the piece K. Finally the crane chain is hauled up and it unwinds from the barrel C,
whilst the chains II are wound thereon, thereby closing the jaws and scraping down
the sides of the hole by the operation of the additional tines or scrapers E E. At
the same time the bucket tines are forced into the ground the circular weight
preventing the machine from rising away from its work and and also keeping it in a
vertical position.
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. The combination with grabs and excavators of additional tines or scrapers which
as the apparatus closes break up the earth around the hole and carry it down to the
outside of the closed grab and excavator substantially as described.

page_text: 2. The improvement in grabs and excavators consisting in attaching a heavy
weight or weights to the axis of the buckets or tines substantially as described.
3. The improvement in grabs and excavators consisting in combining therewith a
heavy hollow cylinder which carries at its lower end the axis of the buckets or tines
and encloses and protects the working parts substantially as described.
4. Our improvements in grabs and excavators substantially as described and
illustrated by the annexed drawings.
Dated this 9th day of September 1887