Improvements in Drill Guides.
Year: 1895

page_text: Date of Application, 20th Sept., 1895
Complete Specification Left, 17th June, 1896-Accepted, 18th July, 1898
Improvements in Drill Guides.
I, DIEDRICH HEINRICH KORFMANN, Junior, of 81 Ruhr Street, Witten on the
Ruhr, in the German Empire, Manufacturer, do hereby declare the nature of this
invention to be as follows:-
This invention relates to improvements in drill guides, and it has for its object
to maintain any desired number of simultaneously advancing drills in the direction
once given to them.
To this end, I provide a guide which embraces the drills and is maintained in
position by pins, or by grooves or notches provided in the drills, and which guide
penetrates with the drills into the aperture or cavity formed by them.
According to one arrangement, the guide or guiding device comprises a number
of tubes cast in one piece, the axes of which are at exactly equal distances from
each other, corresponding to the axes of the drills to be guided.
In order also that the guide may readily pass into the drill holes, I provide, in
each of the two outer drills, a tapped hole into which a pin is screwed, whose
length is equal to the outer diameter of each guide tube. If now in the advance
of the drill, the guide has a tendency to remain behind, it will be prevented by the
two pins in the outer drills, and will be compelled to pass in the same direction as
the drills, and therefore to guide them.
Instead of the guide being moved positively by the drills, by means of the
aforesaid pins, this may also be effected by providing collars in the several tubes,
and which collars fit accurately into corresponding grooves or notches in the
drills, and consequently compel the guide to advance with the drills.
In this latter arrangement, the guide may be formed in halves and be provided
at one end with a hinge for folding, and at the other end there may be provided
a hinge with removable bolts to serve for locking the guide.
1 1005
Improvements in Drum&
1. DIEDRICH HEINRICH KORFMANN, Junior, of 81 Ruhr Street, Witten on the
Ruhr, in the German Empire, Manufacturer, 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, reference being had
to the accompanying drawings and to the letters and figures marked thereon, that
is to say:
This invention relates to improvements in drill guides, and has reference more
particularly to drill guides for coal-cutting machines having a number of
simultaneously working and overlapping drills, the object being to maintain any
desired number of such drills in the direction originally given to them.

page_text: Drill guides heretofore used in connection with coal cutting machines, are
defective in that they cannot advance into the bore hole, and consequently at
great depth the drills easily spread, so that the object of the guiding is only
partially attained, or not attained at all.
Now, according to the present invention, the guide advances into the bore
hole along with the drill, and hence the object of this invention is completely
realized.
As will be seen from the two sections shown in the accompanying drawings, the
guide consists of a number of juxtaposed tubes or sleeves corresponding to the
number of drills t, t, and which drills are enclosed by them. These tubes or
sleeves are firmly connected with each other, or are cast in one piece, and the
distance between their axes is precisely the same as that between the axes of the
drills.
In order that the guide may advance into the bore holes, it is, according to the
arrangement shown in Fig. 1, connected with the drills by pins i, i, screwed
through corresponding holes in the two outer drills, the length of the pins being
not greater than the external diameter of the guide tubes of these drills. Should
the guide r, r, tend to remain behind as the drills advance, the pins will press
upon the edge of the outer tubes or sleeves of the guide and force it to follow the
advance of the drills, and to penetrate with them into the holes.
The drills t, t, are divided into two groups or sets, of which one is arranged
higher than, or in the rear of, the other their cutting edges being S-shaped and of
such a width that the bore holes produced will run into one another, so that the
connecting portions of the tubes may also easily advance into the holes. To this
end, the width of the cutting edges is of a somewhat greater diameter than that of
the guide tubes.
The horizontal section in Fig. 1 is taken on the line x, x.
The arrangement shown in Fig. 2 is substantially the same as that shown
in Fig. 1, but in this case the positive movement of the tubes by the drills is
effected not by pins, but by collars or annular projections in the several tubes
adapted to engage corresponding notches or grooves in the drills. The guide
tubes, in this arrangement, are not shown as combined or formed in a single piece,
but consist of two parts or sections which can be opened and locked by means of
hinges and bolts. This figure also shows a horizontal section taken through
the drill and the guide. The proportional sizes are analogous to those in
Fig. 1.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is-
1. A drill guide for coal cutting machines, having a number of drills working
simultaneously and overlapping one another, characterized by the rigid connection
of a number of tubes (cach of which guides one drill) with a frame which advances
with the drills into the bore holes, the advance of said guide being effected
either by means of pins passing through the drills and bearing upon the
upper edges of the tubes, or by collars and notches or grooves, substantially as
described.
2. My improvements in drill guides, substantially as hereinbefore described and
shown in the drawings.