IMPROVE MENTS IN MACHINERY FOR DRIVING TUNNELS OR SHAFTS
Year: 1882

page_text: LETTERS PATENT to Charles Denton Abel of No. 28 Southampton Buildings
Chancery Lane, in the County of Middlesex for an invention of "IMPROVE
MENTS IN MACHINERY FOR DRIVING TUNNELS OR SHAFTS" A communication
from abroad by Franz Rziha of Vienna and Franz Reska of Prague both
in the Austrian Empire
PROVISIONAL SPECIFICATION left by the said Charles Denton Abel at
the Office of the Commissioners of Patents on the 4th April 1882.
CHARLES DENTON ABEL of No. 28 Southampton Buildings Chancery Lane in
the County of Middlesex "IMPROVEMENTS IN MACHINERY FOR DRIVING TUNNELS
OR SHAFTS [A communication from abroad by Franz Rziha of Vienna and Franz
Reska of Prague both in the Austrian Empire.]
"
This invention relates to an improved construction of machinery for driving
tunnels or shafts wherein a revolving bore-head is caused continuously to cut away
the face of the rock by means of cutters so arranged that one set thereof cut a
series of concentric circular grooves, leaving annular projecting ridges between
them, which are then cut or broken away by another set of cutters, the advance of
the borehead being effected by a cylinder and piston actuated by hydraulic or
other pressure.
For this purpose the cutters of the one set are secured in the circular borehead
in such positions that two, three or more thereof operate to cut one of the circular
grooves, each cutter being however of a smaller width than the groove to be cut,
and all being arranged at different distances from the centre of the borehead, so
that each cutter has its own separate path, leaving a certain amount of uncut
material between the paths of the cutters which material breaks away of itself as
the cutters advance into the groove. The cutters of the other set are arranged to
project a less distance than the first set from the face of the bore-head, being in
such positions as to act upon the annular ridges left between the grooves, and
arranged, like the first set, so as to leave some uncut.material between their paths,
which will break away of itself on the advance of the cutters.

page_text: The cutters are secured in the borehead so as to be removeable from behind, for
which purpose their shanks are made of a tapering or wedge shape and pass
through holes in the borehead into which wedge shaped keys are inserted from the
back face, so as to wedge the cutters tight in the said holes. These keys have
lugs through which pass screws fixed to the borehead and having nuts by which
the keys are tightened up and held securely.
On the periphery of the bore-head are formed oblique ribs or grooves, by the
action of which the excavated material is moved away from the face of the rock as
the boring proceeds.
The borehead is fixed on the end of a plunger working in a horizontal cylinder
supplied with liquid under pressure, compressed air or other suitable source of
motive power whereby the plunger. with the borehead is pressed outwards so as to
cause the latter to bear with its cutters continuously against the face of the rock,
the cylinder being held securely in position by lateral struts consisting by
preference of cylinders formed or fixed on the main cylinder and having pistons or
plungers that are forced outwards by fluid pressure so as to take a bearing
against the sides of the tunnel or shaft and at the same time to exert an upward
pressure on the cylinder; causing it to bear with another strutt against the crown
of the tunnel. The cylinder is also provided with wheels which, when the fluid
pressure is made to escape from the lateral struts, so as to allow the cylinder to
sink slightly, take a bearing upon rails laid on wrought iron hollow sleepers on
the floor of the tunnel the two sleepers being connected by curved bed plates
fitting the floor and serving also to act as conduits for carrying off any water
entering the tunnel.
***
The borehead. with its plunger receives the requisite rotary motion for the
cutting operation by means of a toothed pinion-gearing with a toothed ring on
the borehead, and carried by a shaft driven by any suitable motor engine on the
framing of the boring cylinder. The motion is by preference imparted through a
worm gearing with a worm wheel that revolves with the shaft but through which
the shaft is free to slide. The outer end of the shaft is carried by an arm through
which passes a backward extension of the bore-head plunger of reduced diameter, the
said extension being free to revolve in the said arm, but made to carry it forward
as the plunger advances with the borehead, so that the before mentioned shaft
carried by the arm is also made to advance thereby keeping its pinión in gear
with the toothed ring of the borehead. The boss of the arm through which
the plunger extension passes is supported below by two telescopic struts which
are acted upon by fluid pressure so as to take a bearing against the sides of the
tunnel.
f...
When the borehead and plunger have advanced a certain distance the fluid
pressure is allowed to escape from the cylinder and struts; the borehead" is then
firmly fixed in its position by wedging and the cylinder is advanced' along 'the
plunger by means of screw spindles carried by à cross. head at the back end of the
cylinder and screwing through lugs on the boss of the before mentioned arm
carrying the plunger -extension. The boring cylinder being thus advanced fluid
pressure is again admitted to the struts so as to fix it in position. * Farkas
4

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Charles Denton Abel in the Great Seal, Patent Office on the
3rd October 1882.
1 .
i
CHARLES DENTON ABEL of No. 28 Southampton Buildings Chancery Lane in
the County of Middlesex IMPROVEMENTS IN MACHINERY FOR DRIVING TUNNELS
OR SHAFTS" A communication from abroad by Franz-Rziha of Vienna and Franz
Reska of Prague both in the Austrian Empire
: l'
* .
-
This invention relates to an improved construction of machinery for driving
tunnels or shafts wherein a revolving bore-head is caused continuously to cut away
the face of the rock by means of cutters so arranged that one set thereof cuts a
series of concentric circular grooves, leaving annular projecting ridges between
them, which are then cut or broken away by another set of cutters, the advance of
the bore-head being effected by a cylinder and piston actuated by hydraulic or
other pressure.
The machine consists of the following principal parts -
1. The actual boring apparatus consisting of 'a circular disc of a diameter
corresponding to that of the tunnel, shaft or other boring to be cut, and provided
with cutters arranged in a peculiar way, to be presently described.
:
2. Of apparatus for pressing the bore-head against the surface to be operated
upon and advancing it as the work proceeds.
3. Of apparatus for imparting rotary motion to the bore-head.
4. Of devices for securely strutting the machine against the sides of the
tunnel.
5. Of a device for advancing the parts mentioned under 2, 3 and 4, as the work
proceeds.
6. Of peculiarly constructed wrought iron or steel sleepers.
The construction of the machine will be readily understood on reference to the
accompanying drawings, in which Fig 1 shews a cross section of the machine, Fig 2
a longitudinal section, Fig 3 a part section end view, Fig 4 a view of the strutting
device, Fig 5 a sectional plan, Fig. 6 an enlarged detal of the bore-head and Fig 7
enlarged views of the cutters. The borehead consists of an open disc A which may
be of flat, conical, cylindrical, spherical or other desired shape according to the
nature of the material to be operated. upon, the surface of which has cutters so
arranged in an adjustable manner, as to cut the stone by abrasion in a series of
concentric circular paths of small width, leaving cylindrical portions between them
which either crumble away of themselves, or are cut away by other cutters. Thus
the cutters 1, 2, 3, Fig 7 are arranged to cut the circular groove I and 4 and 5.
another groove II, while the cutters 6, 7, 8, 9 cut away the cylindrical projections
between the grooves. The cutters are furthermore so arranged that each one works
in a separate path as shewn in the drawing, so that small annular projections are
left between them which readily crumble away as the work' proceeds. The size of.
the intervening spaces between the cutters as also the width of the cuts and number
of cutters will depend upon the nature of the stone. The knives are secured by
means of the arrangment shewn at Fig 6, so that they can be removed from
the back while the bore-head is in operation, and be replaced by new ones,
the pressure exerted by them against the stone only tending to fix them more
securely.
:
The complete cutting device consists of the tapering cutter blade m having its
thicker end presented towards the disc, and of a wedge or key n which is forced in
tight or relased by means of the screw O.. This screw has the same inclination as

page_text: the key n and cutter m so that with one turn of the screw the key will be raised
sufficiently to enable the cutter to be drawn out and replaced by a new one: If
the screw is then only moderately tightened, the pressure of the cutter against the
stone will of itself tighten it in its seat. The essential features of the boring
apparatus are firstly the before described peculiar arrangment of the cutters
whereby these are caused to cut concentric circular grooves in the stone, leaving
small projections between the cutters of each group which crumble away as the
work proceeds and leaving larger annular projections between the grooves which
are removed by similar groups of cutters set further back. Secondly, the described
arrangement whereby the cutters can be removed and replaced by new ones as the
cutting operation is proceeding
The arrangement for advancing the bore-head as the work proceeds and for
pressing the same against the stone consist of a press, actuated by steam, com-
pressed air water or other fluid under pressure, which presses the bore-head against
the stone with such force as to cut the same by abrasion as the cutters rotate.
The borehead A is for this purpose connected to the end of the plunger C of the
press cylinder B, the plunger being acted upon by fluid pressure in the cylinder so
as to move outwards as the borehead penetrates. The borehead at the same time
has rotary motion imparted to it from any convenient motor engine; in the
arrangement shewn on the drawing the motor engine which is not shewn, and
which is supposed to be fixed to the framing D E on each side of the cylinder B,
imparts motion to the crank shaft F carrying the worm G (Fig 3) which imparts
rotary motion to the worm wheel H fixed on the shaft I which imparts such
motion to the bore-head by means of a pinion K in gear with an inside toothed
ring Lon the bore-head. The shaft J is carried in bearings on the cylinder B
and in a bearing between collars on an upright M carried by the rear extension
of the plunger C, so that as the plunger advances, the upright M (in which C is
free to turn) causes the shaft J to advance to precisely the same extent, sliding for
this purpose through the worm wheel H and through the bearings on the
cylinder B. Thus the pinion K is always kept in gear with the toothed ring
of the bore-head.
In place of the above arrangement any other might be employed whereby a
rotating motor such as a turbine, water wheel, rotary engine &c is directly connected
to the bore-head. The essential feature of the above apparatus for advancing and
imparting rotary motion to the bore-head consists in connecting the bore-head
directly to the plunger or piston rod of a press or cylinder worked by fluid pressure,
whereby the bore-head is advanced and pressed against the stone, while at the same
time rotary motion is imparted to it by power applied by a motor engine to
the circumference of the bore-head, either at a single point or at several points
simultaneously or alternately. On the sides of the cylinder B are fixed or formed
four smaller cylinders N¹ N2 N3 N' having pistons or plungers P1 P2 P3 P4 that are
pressed outwards by fluid pressure so as bear with their enlarged heads against the
cylindrical surface of the tunnel or shaft. Two similar struts P³ Po worked by
screws, wedges or other means are provided at the top of the cylinder B for taking
a bearing against the crown of the tunnel or shaft. Fluid pressure being admitted
to the cylinders N¹ &c the pistons P¹ &c are pressed outwards and in taking a
bearing against the sides of the tunnel, lift the entire machine to such an extent
as to cause the strutts P5 P6 to bear against the crown of the tunnel, thus holding
the machine securely in the raised position. The cylinders N¹ &c are connected to
the reservoir of fluid pressure by pipes provided with cocks or valves, not shewn,
so arranged as to enable fluid pressure to be admitted to any one or more of the
cylinders independently of the others so as to allow of an adjustment of the axis
of the machine both in a horizontal and a vertical direction. If the material to be
operated upon is of a very friable nature, iron or steel segmental shields such as
are shewn at Figs 1 and 3 may be held up against the crown of the tunnel by the
struts P5 P, so as to secure the same from falling in at the point of operation. The
essential feature of the above described arrangement consists in not only enabling

page_text: the machine to be firmly held against the axial and radial pressure produced by the
boring operation, and to be protected against the falling in of the roof, but also.
enabling the longitudinal axis of the machine to be adjusted accurately so as 'to
correspond with the direction required to be given at any one point to the axis of
the tunnel or shaft. When the boring or cutting has proceeded to the extent to
which the plunger C can be advanced, the plunger and the bore-head A must be
held stationary while the cylinder B and parts connected therewith are advanced
in their turn For this purpose the bore-head A is fixed by wedging and the two
small strutting plungers p' p² (Fig 4) which are attached to the upright M and
consequently to the rear end of the plunger C are caused by fluid pressure to press
against the sides of the tunnel so as to hold the plunger C and consequently the
bore-head firmly in position. The plungers P¹ &c being now relieved of fluid
pressure, by the discharge of fluid and also drawn inwards by producing a partial
vacuum behind them, the cylinder B and parts connected thereto will be free to be
slid forward upon the plunger C, held as before described, such forward motion
being effected by screws U U carried by the upright M and rotated by the hand
wheel T. When this advance has been effected to the extent of the stroke of the
plunger C the machine is again fixed in position and adjusted by the struts P¹ &c
and the bore-head and plunger being freed from their supports the work of boring
is again proceeded with. Instead of advancing the cylinder B and its apurtenances
by screws as described, this may be effected by means of hydraulic, steam or other
power. It will be evident that the above described means for advancing the entire
machine in the boring may also be employed for moving it backwards, and
consequently for withdrawing the machine altogether from the tunnel when
necessary.
The essential feature of the above described apparatus for advancing the boring
machine as the work proceeds, consists in the arrangements whereby on the one
hand the cylinder B and its apurtenances can be fixed and the plunger C and
borehead A advanced relatively to it, while on the other hand the bore-head and
plunger are fixed and the cylinder B advanced relatively thereto, these operations
taking place consecutively and continuously until the boring is completed.
As the work of boring proceeds the debris falling down are automatically
conveyed backwards by the bore-head itself, this being provided with oblique or
screw like projections S on its outer surface, which push the debris backwards
towards endless chain buckets, not shewn on the drawings which carry them
farther back into the space R whence they are conveyed away by any known
means.
Curved wrought iron or steel sleepers W are employed for carrying rails on
which the wheels of the boring machine run, which sleepers permit any water that
may enter the tunnel to flow off and also allow of the easy removal of the debris
from the space R.
Having thus described the nature of this invention and in what manner the
same is to be performed as communicated to me by my foreign correspondents, I
claim :-
First. The herein described construction of continuously acting boring machinery
for tunnels shafts and the like, wherein a continuously rotating and advancing.
bore-head is caused by direct pressure to cut a cylindrical boring in the rock.
Second. The herein described mode of securing the cutters in the bore-head by
means of a wedge and screw.
Third. The herein described arrangements whereby the direct pressure of steam
or other fluid is caused to press the cutters of the bore-head against the rock so as
in rotating with the bore-head, to cut circular grooves, leaving between them
concentric annular projections or cores which are afterwards broken off or which
crumble away of themselves.
Fourth. The herein described arrangement for strutting the machine against the
sides of the boring by the action of fluid under pressure on plungers or rams,
whereby the alternate advance of the bore-head and plunger on the one hand and

page_text: of the cylinder and its apurtenances on the other hand can be effected, and whereby
the axis of the machine can be adjusted to any desired position..
I
Fifth. The use of the herein described curved wrought iron or steel sleepers..
In Witness whereof I the said Charles Denton Abel have hereunto set my
hand and seal this third day of October in the year of Our Lord One
thousand eight hundred and eighty-two.
CHA³. D. ABEL. (L.S.)