Improvements in Excavating Apparatus.
Year: 1894

page_text: Date of Application, 16th Jan., 1894-Accepted, 17th Feb., 1894
COMPLETE SPECIFICATION.
Improvements in Excavating Apparatus.
I, THOMAS WHITAKER, of Horsforth, near Leeds, in the County of York,
Contractor, do hereby declare the nature of this invention and in what manner
the same is to he performed, to be particularly described and ascertained in and by
the following statement:-
This invention relates to that class of excavating apparatus in which the work is
performed by a bucket or its equivalent carried by an arm oscillating about a pivot
on a crane jib. It is designed with the object of providing improved means for
altering the radius of the arm and moving the bucket to and from the face of the
material without altering the position of the whole machine. And also to provide
means whereby the same machine may be utilised for excavating on land by the
scoop or bucket and for dredging in water by a grab.
The radius or oscillating arm or bracket which carries or to which the excavating
bucket is attached is constructed with a rack by which it can be moved to and fro
longitudinally by a toothed wheel and to the shaft which carries the ruck wheel I
connect a steam cylinder or small steam engine whereby the rack wheel can be
rotated in each direction and the radius arm and excavating bucket moved
backwards and forwards as required. And on the rack shaft I also place a
barrel or drum by which a double chain grab can be operated when the bucket is
removed.
It will be fully described with reference to the accompanying drawings.
Fig. 1. Side elevation of apparatus.
Fig. 2. Side elevation of part of radius arm and jib showing the racking
mechanism and the steam cylinder or engine for actuating it.
Fig. 3. Front elevation of same.
The crane A and the jib B are constructed in the ordinary way and the winding
mechanism is not shown in detail as it may be of any ordinary or well known
construction.
The radius arm or bracket C to which the excavating scoop D is attached is
provided with a rack E on each side running part of its length. A toothed
wheel F on each end of the shaft gears with the rack and by them the radius
rod C may be moved backwards and forwards. The radius rod or bracket C
moves about the shaft f as a pivot so that as it is moved to and fro the radius of
the circle within which the scoop D moves is increased or reduced or the scoop
or bucket D is advanced to or drawn back from the face of the earth which it is
cutting or it is moved in either direction to deposit the soil in any desired
place.
It has been found heavy and difficult work for a man to turn or work the rack
wheels F by hand so I now construct the apparatus to work them by steam power.
To the upper side of the jib B I attach a small steam engine with two cylinders G H
each connected to a crank shaft I by the connecting rods g h connected to the
piston rods g¹ h¹. The engine is provided with eccentrics i and valve gear and
reversing link K. The crank shaft I is geared to the rack wheel shaft ƒ by the
train of wheels L.
On the rack shaft fI also fix a barrel or drum M so that when the excavating
scoop or bucket D and the radius arm or bracket C are taken off the apparatus
may also be employed for working double chain grabs by a small chain or wire rope
worked over the pulley on the jib head onto this barrel or drum M for opening or
closing the grab.

page_text: Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
1. In an excavating apparatus provided with a rack and rack wheel for moving
the radius arm and scoop or bucket to and fro the combination therewith of a steam
engine placed on the side of the jib whereby the rack wheel and rack are actuated
substantially as described and shown.
2. In an excavating apparatus of the type described the combination with the
rack shaft of a steam engine affixed to the jib for actuating it and a drum or barrel
such as M placed on the said shaft whereby when the radius arm and scoop or bucket
are removed the apparatus can be applied to actuate a double chain grab substan-
tially as described and shown.
WM. P. THOMPSON & Co.,
Manchester, Liverpool, and London, Patent Agents.