IMPROVEMENTS IN MACHINERY FOR BRINGING DOWN COAL OR OTHER MINERALS
Year: 1884

page_text: We GEORGE ARTHUR CROW of 86 Park Road and WILLIAM HEWSON CROW
of 45 Rye Hill both in the City and County of Newcastle upon Tyne Engineers,
do hereby declare the nature of said Invention for "IMPROVEMENTS IN MACHINERY
FOR BRINGING DOWN COAL OR OTHER MINERALS" to be as follows:-
.
Our Invention consists of a combination of wedges connecting rods and segmental
blocks so arranged as to expand or contract the segmental blocks as required. And
of a mechanical arrangement for working the aforesaid parts whereby sufficient
power is given forth to burst or bring down the coal.
For this purpose the end of centre connecting rod is screwed; on this a revolving
nut is worked by a worm wheel this wheel being operated by a worm the bearing
of the said worm and wheel being in the centre and attached to the two outside
connecting rods.
.
The front wedge next the face of the coal is forged on or attached to the
centre connecting rod; another wedge, at the opposite end of segmental blocks, is
attached to the outside connecting rods, both being worked simultaneously by the
inechanical arrangement before described.
The thin ends of the wedges are thus brought together and the segmental blocks
expanded at both ends.
To make the machine as light and compact as possible we propose to make the
wedges on their inclined surfaces either a regular radius or of two or more radii,
thereby increasing the power of the machine when it is most wanted that is just
before the coal is brought down.
To apply the machine a hole is first made in the coal just sufficiently large to
admit the machine when it is contracted to its smallest compass, and the worm
gearing being operated by manual or other power the wedges are caused to approach
each other expanding the segmental blocks with a force gradually increasing as the
resistance increases to split up and bring down the coal.

page_text: We, GEORGE ARTHUR CROW of 86 Park Road and WILLIAM HEWSON CROW
of 45 Rye Hill, both in the city and county of Newcastle upon Tyne, Engineers,
do hereby declare the nature of said invention for "IMPROVEMENTS IN MACHINERY
FOR BRINGING DOWN COAL OR OTHER MINERALS" and in what manner the same
is to be performed to be particularly described and ascertained in and by the
following statement:―
Our invention consists of a combination of wedges, connecting rods and segmental
blocks, so arranged as to expand or contract the segmental blocks as required. And
of a mechanical arrangement for working the aforesaid parts whereby sufficient
power is given forth to burst or bring down the coal..
For this purpose the end of centre connecting rod is screwed, on this a revolving
nut is worked by a worm wheel, this wheel being operated on by a worm, the
bearing of said worm and wheel being in the centre and attached to the two
outside connecting rods united at one end.
The front wedge next the face of the coal is forged on or attached to the centre
connecting rod, another wedge at the opposite end of segmental blocks is attached
to the outside connecting rods, both being worked simultaneously by the mechanical
arrangement before described.
The thin ends of the wedges are thus brought together, and the segmental blocks
expanded at both ends.
To make the machine as light and compact as possible, we propose to make the
wedges on their inclined surfaces either a regular radius or of two or more radii,
thereby increasing the power of the machine when it is most wanted, that is just
before the coal is brought down.
To apply the machine a hole is first made in the coal, just sufficiently large to
admit the machine when it is contracted to its smallest compass, and the worm
gearing being operated by manual or other power the wedges are caused to approach
cach other expanding the segmental blocks with a force gradually increasing as the
resistance increases to split up and bring down the coal.
In order that the said invention may be fully understood we shall refer to the
several figures on the sheet of drawings hereunto annexed, the same letters
indicating corresponding parts throughout all the figures.
an end elevation of the
Figure 1 shews a sectional side elevation and Figure
machine with the segmental blocks in a contracted position.
Figure 3 shews a plan of same.
Figure 4 shews an end elevation of worm and wheel.
Figure 5 shews a sectional side elevation, and Figure 6 an end elevation with
the segmental blocks expanded to their utmost extent.
From the drawings it will be seen that by turning the worin A, by means of a
ratchet or handle on square end H, motion is given to worm wheel B, the effect of
which is that the centre screwed connecting rod C, which is forged or attached to
the curved wedge D; is forced forward, thus dividing the segmental blocks E. The
outside connecting rods F being attached to another curved wedge G are also
operated on simultaneously, and the wedges are thus brought together, and the
segmental blocks expanded sufficiently to burst or bring down the coal.
To apply the machine a hole is first made in the coal, just sufficiently large to
admit the machine when. it is contracted to its smallest compass as shewn in
Figure 1.

page_text: Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed We declare what
we claim is
1st In a machine for bringing down coal or other minerals; The combined
arrangement of the following parts-Worm, worm wheel, screw, connecting rods or
bars and wedges operating and expanding segmental blocks simultaneously.
Constructed and operating substantially as shown and described.
2nd The curved or varying inclined form of wedge by which a gradually increasing
force is exerted as the resistance increases.
Dated the 23rd day of December 1884.
GEO. A. CROW.
W. H. CROW.
Witness,
I. J. DAWSON, F. Inst. P.A.,
Consulting Engineer & Patent Agent,
Newcastle on Tyne.