Improvements in Apparatus for Excavating, in Part Applicable to Cranes.
Year: 1889

page_text: Date of Application, 18th Jan., 1889
Complete Specification Left, 18th Oct., 1889-Accepted, 23rd Nov., 1889
PROVISIONAL SPECIFICATION.
Improvements in Apparatus for Excavating, in Part Applicable to
Cranes.
I, THOMAS WHITAKER, of Horsforth, Near Leeds, in the County of York, Contractor,
do hereby declare the nature of this invention to be as follows
-
This invention relates to that class of excavator known as a crane navvy in which
the excavating bucket is pivoted to the jib of a crane, as described in the specifications
of my former patents No. 1670.1 of 1886 and 2757 of 1887.
The present improvements are primarily designed to perfect the apparatus for
ditching or digging out at a lower level than that on which the apparatus stands,
though part may also be applied to the crane navvy for ordinary excavating and also
to ordinary cranes.
The crane navvy, when engaged in ditching or excavating at a level lower than that
upon which it stands as the work proceeds travels along supported on beams over the
excavation that has been made. For this reason it is necessary to lay a fresh
track at intervals as the work proceeds or to remove the track from behind and
lay it in front. As the beams which constitute the track and carry the rails are
necessarily heavy this is laborious work when performed by manual labour. It is
also desirable that the excavation should occur perpendicularly or nearly so and
the bucket should travel in an approximately straight path in preferance to travelling
in the arc of a circle.
To the tail of the crane or base of the apparatus is attached a drum worked by
a worm wheel or other suitable or convenient gear. This drum carries a winding
chain with which it lifts its own road or track the same being carried to the front
by rotating the crane on its central pivot and is there deposited. The track or road
is inade in short length which in this way is easily carried from on position to
another as the work proceeds.
The bucket is pivoted at the end of the rod or arm which carries it and is there
secured or fixed in position by a chain hung on a catch which can he released by
the pulling of a rope. It is held in this position until it reaches the bottom of the
excavation when the catch is released and as operations begin it is pulled forward on
its pivot by the haulage of the chain until it assumes a position at about right
angles to its previous position where it is stopped by a stop or catch coming against
the rod or arm. The rod or arm moves in slides slots or guides or is connected to
a pivot that so moves and is provided with a rack working in a toothed wheel or with
other mechanical device which will allow it to move so as to shorten the radius of
the bucket. As the bucket is drawn up by the chain the brake controlling the rack
wheel or other device is released sufficiently to allow the bucket to gradually
recede as it passes up the face of the cutting and thus cut a perpendicular face.
The auxilary winding drum may be attached to the tail of an ordinary crane to
enable it to lift and lay its own road or track when being worked ower sewers or the
like or in any other position where the removal and relaying of the road is required.
Dated this 17th day of January 1889.

page_text: COMPLETE SPECIFICATION.
Improvements in Apparatus for Excavating, in Part Applicable to
Cranes.
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
be performed, to be particularly described and ascertained in and by the following
statement :-
This invention relates to that class of excavator now known as a crane navvy in which
the excavating bucket is pivoted to the jib of an ordinary portable crane such
as described in the specifications of my former patents Nos. 16701 of 1886 and 2757
of 1887.
The present improvements are primarily designed to perfect the apparatus for
excavating to a lower level than that on which the apparatus stands, though part may
also be applied to the crane navvy for ordinary excavating and also to ordinary
cranes.
The crane navvy, when engaged in ditching or excavating at a level lower than
that upon which it stands as the work proceeds travels along supported on beams
over the excavation that has been made. For this reason it is necessary to lay a
fresh track at intervals as the work proceeds or to remove the truck from behind and
lay it in front; as the beams which constitute the track and carry the rails are
necessarily heavy this is laborious work when performed by manual labour. It is
also desirable at times that the excavation should be made perpendicularly or nearly so
and the bucket should travel in an approximately straight vertical path in preference
to travelling in the arc of a circle and the object of the invention is to provide means
for carrying these into practice.
It will be clearly described with reference to the accompanying drawings in
which
Fig. 1 is a side elevation of a crane navvy showing the present improvements in
one form.
Fig. 2 is an end elevation of same.
The
Fig. 3 is a sido elevation of crane navvy designed for oxcavating sewers.
A is the carriage and B the jib of an ordinary portable crane constructed in any
suitable manner. To the tail of the crane is affixed a drum C supported by the
brackets c and rotated by a worm and worm wheel d from the hand wheel D.
drum C carries one or two winding or hoisting chains E which extend down and
engage with the road or track F. The track or road is made in short lengths so
that a portion of any given length may be lifted without disturbing the other parts.
The hooks e on the chains E will be caused to engage with one of the sleepers or
other part of the track when it is desired to lift or replace a portion of the track and
the track raised and suspended at the tail of the crane by rotating the crane on its
central pivot the portion of the track which has been lifted, or picked up from behind
may be relaid in front of the machine as work progresses.
Referring to Fig. 1 the arm H of the bucket is formed with a slot or slide h in
which rests or slides the pivot I. upon which it oscillates.
To the arm is attached a rack L which gears with the wheel of the train of
wheels m actuated by the hand wheel M and controlled if required by a strap brako or
other suitable form of brake. Instead of a train of spur wheels a worm on the hand
wheel shaft and a worm wheel may be substituted.
The object of this device is to shorten the radius of the bucket. As the bucket G
is drawn up the face of the excavation by the chain it is caused or allowed to recede
as it passes up the face of the cutting either by the attendant moving the hand
wheel M or releasing or slackening the brake and thus a perpendicular face may be
cut. By the same mechanism the bucket may be run in or out to deposit the excavated
material in any particular spot.

page_text: Tho
Referring to Fig. 3 the apparatus is shown designed for excavating sewers.
scoop or bucket G is pivoted at the end of the arm H on the pin or pivot y. The
bucket is held in a position beyond the end of the arm H by a small chain O one end of
which is attached to the bucket and the other end engages with a small catch P.
pivoted to the arm H. The catch P. is held when the bucket is in the position
shown in dotted lines by the bar or lever R. which can be withdrawn by the
cord r.
The arm H. is formed with a series of teeth at each side which form
racks L which gear with the wheels l.
Instead of the pin or pivot I and slide shown in Fig. 1. a small cradle ['
pivoted to the shaft i with rollers hold the racks in gear with the pinions l. The
bucket is held in the position shown in dotted lines until it reaches the bottom of
the excavation when the catch P. is released and as operations begin the bucket is
pulled forward on its pivot g by the haulage of the chain until it assumes the position
shown in full lines at about right angles to its previous position. It is here stoppedi
by a stop g against the rod or arm H. As the excavation proceeds the brake or
handwheel is released as herein before described and the bucket travels approximately
in a straight line up the face of the cutting.
The auxiliary winding drum may be attached to the tail of an ordinary crane
to enable it to lift and lay its own road or track when being worked over
sewers or the like or in any other position when the removal and relaying of the
road is required.
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. The combination with a crane-navvy or ordinary portable crane of an auxiliary
drum and winding chain affixed to the tail of the crane substantially as and for
the purpose described.
2. A bucket arm or excavating attachment for an ordinary portable crane having
the bucket pivoted or hinged to the end thereof so as to excavate in a straight
instead of a curved path substantially as described.
3. In a crane navvy such as described in my former patents Nos. 16701 of 1886
and 2757 of 1887 a bucket arm having a longitudinal slide or slot, in which the
pivot rests or slides, in combination with the rack L wheels Im and hand wheel M
substantially as described and shown.
Dated this 12th day of October 1800.
WM. P. THOMPSON & CO.,
6, Bank Street, Manchester, Patent Agonts.