Improvements in and connected with Rock Drills.
Year: 1896

page_text: Date of Application, 26th Nov., 1896-Accepted, 24th Dec., 1396
COMPLETE SPECIFICATION.
Improvements in and connected with Rock Drills.
We, ALBERT WILLIAMS DAW, and ZACHARIAS WILLIAMS DAW, both of
Mansion House Chambers, 11 Queen Victoria Street, in the City of London,
Mining 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:-
The present invention relates to, first, improved means for securing or clamping
the cradle in which a rock drill works in the required position upon a column or
other suitable support; and, second, an improved arrangement for securing or
clamping the drill tool within its holder or chuck.
The method of carrying out the first improvement is illustrated in Figs. 1 and 2
of the accompanying drawings, Fig. 1 being a vertical section taken through the
drill cradle and the column or support to which it is to be secured, and Fig. 2 a
plan view of Fig. 1 with the drill cradle removed.
Figs. 3 and 4 illustrate the method of carrying the second improvement into
effect, Fig. 3 being a longitudinal section through the holder or chuck showing the
shank or end of the drill tool within the socket in same, and Fig. 4 a transverse
section through the clamping bolt.
At the
Referring to Figs. 1 and 2, A is the column or support to which the drill
cradle B is to be secured. The clamp is formed in two similar sections C and C
situated respectively on the opposite sides of the column or support A.
opposite ends these sections C, C, of the clamp are provided with bolts D, D¹,
which serve to secure them together, while towards the centre a bolt E is situated
and its head e fits into a suitable seat provided in the under part of the drill
cradle B. Between the central bolt E and the outer bolt D' the sections C, C of
the clamp are each provided with a semicircular enlargement c, c', which embrace
the outer surface of the column or support A.
The central bolt E passes through a bush F provided with a central collar f
which is capable of a limited movement within circular recesses G, G1, formed
respectively in the under surface of the upper section C and the upper surface of
the lower section C of the clamp, while the upper and lower ends of such bush
project respectively in an upward and downward direction through the thickness
of the metal of such sections at this point. A disc H fits over the lower end of
the bush F, the lower end of bolt E projecting through such dise and being
provided with a nut e' serving to tighten up such bolt.
The periphery of the disc H is made conical as shown at h, and enters a
correspondingly shaped seat formed in the under side of the section C', without
however coming into close contact with such seat even when the central bolt is
fully tightened. The upper side of the top section C of the clamp is also formed
with a conical seat c² corresponding to the seat in the under side of the lower
section C above referred to, and into this top conical seat fits a projection b
formed on the under side of the drill cradle B, the periphery of such projection
being made conical as shown. The head e of bolt E as above stated fits into a
recess in the upper surface of the projection b on the drill cradle.
It will be seen that by tightening the bolts D, D', the two sections C, C' of the

page_text: clamp will be drawn together and so securely fastened or clamped to the column
or support A. By tightening up the bolt E the projection b on cradle B will be
drawn firmly into the seat c2 in the upper surface of section C of the clamp, and
the continued tightening of such bolt will force the collar of bush F upwards to
its extreme limit within the seat G of such section C, so that the cradle B will
be firmly clamped to and consequently made perfectly rigid with the sections C, C
constituting the clamp, and which as above stated are in their turn firmly clamped
to the column or support A.
It will be seen that by loosening the bolt D' the whole of the clamp can be
shifted round the column or support A, carrying the drill cradle anl drill with
it to any desired position, and then be again secured by re-tightening the
bolt D¹.
By loosening the central bolt E the drill cradle B can be rotated round much
bolt to any desired position, and then secured there by re-tightening such bolt.
As the seat 2 in the upper section C of the clamp and the seat in the lower
section of the clamp are identical, it will be seen that the bolt E and cradle B
can be drawn out of the two sections C, C', the nut el and disc H having been first
removed from the lower end of the bolt. The bolt E carrying the era lle B with
it can then be inserted through the sections from the unler side, so that the pro-
jection on the cradle will then fit within the seat c³ in the under side of section C'
of the clamp, and by then placing the disc H within the seat on the upper side
of section of the clamp, and screwing up the nut e', the cradle and drill will then
be secured in position so as to be able to work below the column or support A
instead of above same as shown in Fig. 1.
Referring to Figs. 3 and 4, I is the chuck or holder to receive the boring tool
or drill J, which it will be seen passes through a bush or lining inserted in the
outer end of the socket to receive the shank of such tool. The holder or chuck I
has a part of the metal removed at a certain point so as to form a vertical
opening K passing through the body of same and which is of approximately the
form of a bottle, and within this opening a bolt L of corresponding form is inserted,
the neck or shank of same passing out through the top of the chuck or holder I and
being screw-threaded to receive a nut / for effecting the clamping of the drill tool.
This bolt L has a longitudinal opening passing through it from side to side which
is of lightly eccentric or elongated form.
The operation of the device is as follows :-The bolt L having been inserted in
the vertical opening K formed in the body of the chuck or holder I so that the
opening in such bolt is in line with the socket of such chuck or holder, the shank
of the drill tool J is inserted in such socket and passed through the hole in the
bolt L, its inner end projecting beyond same into the continuation of the socket
in the chuck or holder. The nut being then screwed upon the shank of the
bolt L, and tightened up, it will be seen that the drill to l will be firmly clamped
within such chuck or holder.
Having now particularly described and ascertained the nature of our said inven-
tion, and in what manner the same is to be performed, we declare that what
we claim is :-
1. The improved device for clamping the cradle of rock drills to a coluian or
support, consisting in a clamp composed of two sections provided with seats to
embrace such column or support and with tightening bolts for drawing such sections.
towards each other, in combination with another bolt also passing through the clamp
sections and engaging the under side of the drill cradle so as to enable the latter
to be rigidly clamped or secured to the clamp sections, such clamp sections being
formed so that the drill cradle can be clamped to either the top or bottom of such
sections, substantially as and for the purpose specified.
2. The improved means for clamping a drill tool within its holder or chuck
consisting in a bolt inserted in an opening at right angles to the socket of such
chuck or holder and having an opening or eye of elongated form through which

page_text: the shank of the drill tool passes, so that by tightening such bolt the tool will be
firmly clamped or secured, substantially as and for the purpose specified and as
shown in Figs. 3 and 4 of the drawings.
Dated this 26th day of November 1896.
ALLISON BROS.,
Agents for the Applicants.