Year: 1886

page_text: I, JAMES GARVIE junior of 172 Fenchurch Street in the city of London, Engineer,
do hereby declare the nature of my said invention to be as follows:-
My invention relates to improvements in mechanical excavators and has for its
object their construction in such a manner as to be economical in first cost and in
maintainance.
In the mechanical excavators as generally constructed with one bucket, tbe
bucket is guided by a radiating arm attached to the machine but in the excavator,
of my invention the bucket travels along suitable guides which may be substituted
for the jib or corresponding part of an ordinary crane or other convenient apparatus,
or the jib or corresponding part may be retained and the guides attached thereto,,
or they may form part of a special machine. They are arranged vertically or at an
angle from the vertical and are curved at their lower ends so that the bucket may
cut its own way from the bottom of the excavation. The bucket is worked by the
lifting chain of an ordinary crane or.corresponding part of other machines.
The mode of operation is as follows:-
'
Suppose the apparatus to be attached to an ordinary steam crane. The bucket is
run to the bottom and the crane brought up to the face of the cutting. The bucket
is then lifted up and as it rises its lip cuts off a portion of the material which falls
into it. When it reaches the top the crane is swung round. and the bucket
discharged in the ordinary manner, run down, and the crane again swung round to
its work.

page_text: I, JAMES GARVIE junior of 172 Fenchurch Street in the city of London, Engineer,
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:-
My Invention relates to improvements in mechanical excavators and has for its
object their construction in such a manner as to be economical in first cost and in
maintainance. In the mechanical excavators as generally constructed with one
bucket, the bucket is guided by a radiating arm attached to the machine; but in
the excavator of my invention the bucket travels along suitable guides.
In the form in which I preferably construct my apparatus, the guides, together
with their stays and jib attached, are substituted for the jib of an ordinary
locomotive steam crane and operated by its mechanism.
The principal advantages of an excavator of this construction over others in use
are as follows:-The excavating machinery attached to the crane can easily and
quickly be replaced by an ordinary jib thus allowing the crane to be used for
lifting purposes when not required for excavating. There is also a saving in
platelaying as the same rails that the crane runs on can be used for the transport
of the necessary wagons. It is calculated that an ordinary four-ton crane with
this gear attached will excavate almost if not quite as much as an ordinary steam
navvy at half the expense for attendance and at half the first cost. It is also
lighter and therefore easier of transportation.
In the accompanying drawing the apparatus is shown attached to an ordinary
steam crane, fig. 1. being an elevation and fig. 2. a section, to an enlarged scale,
through guides at a x fig. 1.
:
A is an ordinary locomotive steam crane with lifting chain a and derricking
chain a¹ operated in the usual manner.
B are the guides attached to jib B¹, they are stayed in a suitable manner_and
have angle irons 6 to guide the bucket, and stops b¹ to limit its movement. They
are curved at their lower end to allow the bucket to cut its own way from the
bottom of the excavation.
C is the bucket guided by rollers c which run in angle irons b. It is operated by
means of lifting chain a which passes round sheave. o connected to framing c
pivotted to the bucket at c and having guide rollers o' or other suitable contrivance
to enable the bucket to be easily hauled from its lowest position shewn in dotted
lines. The bucket is discharged by means of a door c in the bottom, which when
opened allows the material to fall out.
The mode of operation is as follows:-
The crane with apparatus attached is brought up on rails laid for it to the face
of the excavation. The bucket C having been lowered to the stops b¹ at bottom of
guides B, the jib head is, by means of the derricking chain a¹, let out about 8 inches
until the bucket touches the ground at the bottom of the excavation. The bucket
is then pulled up by means of the lifting chain a, taking a cut of about 6 inches
deep in the face of the excavation sufficient to fill it by the time it reaches the top,

page_text: the apparatus being in such a forward position as to admit of this. The jib head is
then drawn back about 8 inches to free the bucket from the excavation and slewed
round in the ordinary manner until the bucket is directly over the truck or wagon
placed to receive its contents. The catch of the door o³ at bottom of bucket is then
released allowing the door to fall to an angle of about 60° forming a shoot for the
material which discharges itself into the truck or wagon. The crane is then slowed
round bringing the bucket again to the face of the excavation and the above actions
repeated, the door of the bucket being closed as it reaches the bottom of the guides.
When necessary the crane propels itself forward by its ordinary propelling gear.
In the foregoing description and accompanying drawing I have described and
illustrated the apparatus in the form in which I preferably construct it, i.e. with
the guides and jib formed together and attached to an ordinary steam crane, but
the jib of an ordinary crane could have the apparatus temporarily connected to it;
or, instead of the guides being rigidly fixed to the jib they might be pivotted at the
top or otherwise attached and provided with a rack and pinion or other suitable
mechanism for altering the angle of guides or for feeding them forward. I have
also shewn the upper portion of the guides vertical and the lower horizontal, but
they could obviously be at an angle if desirable. The apparatus could also be
attached to, or form part of, any suitable machine other than a crane.
do
Having now particularly described and ascertained my invention and the manner
in which it is to be performed, I wish it to be particularly understood that
not bind myself to the exact details shewn and described, but I do declare that
what I claim is :-
1. Excavators having a bucket travelling in guides shaped at the bottom in such
a manner as to enable the bucket to cut its own way from the bottom of the
excavation.
2. The general construction of the bucket and guides in such a manner as to be
readily attached to, or detached from, an ordinary locomotive steam crane or other
suitable machine, substantially as shewn and described.
Dated this 19th day of November 1886.
JAMES GARVIE, JUNE.