Improvements in and Connected with Rock Drills.
Year: 1888

page_text: Date of Application. 15th Feb., 1888
Complete Specification Left, 9th Nov., 1888
Complete Specification Accepted. 14th Dec.. 1888
PROVISIONAL SPECIFICATION.
Improvements in and Connected with Rock Drills.
1. GEORGE WILLIAM ELLIOTT, of Wharncliffe Villa. Meersbrook Bank, Sheffield,
Yorkshire, Mining and Mechanical Engineer do hereby declare the nature of this
invention to be as follows:
This invention relates to improvements in the construction of nuts and break gear
of the main screws, and in the sockets for holding them, whereby the rate of pro-
gression of the main screws through their nuts is capable of being regulated to suit
the various degrees of hardness of the material bored; also to improved sockets for
connecting the main screws to the drills, and split nuts of improved construction,
in order to facilitate the changing of the drills; also to improved sections of steel
or iron for constructing telescopic standards for such machines and the mode of
forming a sliding connection between the two parts of the telescopic standards;
and an improved standard for fixing to the material to be bored, by means of a
short hole bored into the material; and an arrangement of gearing for actuating
the main screw.
One of the improvements in the nut, break gear, and socket for holding them, is
the manner of arranging balls at each end of the nut so as to take the thrust,
and by providing a rolling contact, to reduce the friction between the nut and its
abutments, below that of the nut on its thread, to allow the nut to revolve with
its screw.
A groove is made at each end of the nut and its abutments, for a path,
for the balls, and the balls are kept in their positious relative to each other, by
means of a washer pierced with a hole for each ball, and allowed to revolve freely
around the main screw, as the balls roll in their paths; by this means much fewer
are required than is the case when no pierced washer or cage is used.
.
The break is arranged in two parts, a strap and a block sliding within it a
forced together to grip the nut; or a screw and a pad or saddle between it and
the nut may be used.
The socket for the nut is made like a tube, with a trunnion at each side for.

page_text: hanging it to the standard. The hole through the tube is large enough to admit
freely the nut of the main screw, which is cylindrical in form, and after the nut and
one kind of break arrangement has been inserted, each end of the socket is fitted
with a bush, either screwed into it, or otherwise secured therein.
The inner ends of these bushes each form the abutment for each end of the nut,
and are grooved to form the paths for the balls which are placed between the nut
and its abutments. The internal diameter of these bushes is equal to the diameter
of the main screw, and they form a guide for the main screw.
One end only of the socket may be left open to admit the nut, and the other end
to fit the main screw, so that a bush is required at one end only of the socket. The
chief advantage of making the socket with a bush at one or both ends is, that these
bushes form when screwed into the socket a ready means of adjusting the fit of the
nut and its abutments, which require a nice adjustment to make them work properly.
There is an opening in the centre of the socket at one side, between the trunnions
to admit of the insertion of the break arrangement for the main nut in one arrange-
ment of it and in another arrangement a recess for the pad and boss for the screw is
provided.
Instead of making the socket as above described, it may be constructed with two
tubes, for guiding the main screw, connected together by two straps, which also have
each a trunnion projecting from it, to hand the socket to the standard. By having
the two side straps only, the inner ends, of the two tubes can readily be trued up at
right angles to the axis of the main screw, nut, and nut socket, to receive a plate of
metal, with a groove to form the path for the balls.
A plate or cover is provided for each of the open sides to cover up the nut and
its fittings, one of the plates having provision made in it for the break arrange-
ment as described for the tubular socket.
Instead of inserting the nut, and the two plates and the balls, between the two side
straps, and then inserting the main screw through the two tubes, as is necessary in
this arrangement, one or both the tubes may be made large enough to allow the nut
to pass through it, and an inner bush inserted afterwards, as described in the arrange-
ment for the tubular socket. When this is done, separate plates having grooves for
the balls, are not required.
Another arrangement for obtaining an adjustable feed, but which only permits one
end of the main screw to be used to hold the drill, is by providing a casing for the
nut and balls or their equivalent at one end of the nut only, to reduce the friction
between the end of the nut and its abutments below the friction of the nut and the
threads of the screw.
The balls are placed between the end of the nut, and a cap or ring which bears
against the end of a strong spring or yielding substance placed between this ring and
the end of the casing. An adjustable stop prevents the nut from reyolving until the
pressure on the drill compresses the yielding abutment of the nut to the required
degree, when the nut is freed from the stop and is allowed to revolve with the screw,
and the screw ceases to progress through the nut until the pressure on the drill is
reduced to allow the yielding abutment to again bring the nut in contact with the
stop.
The feed may also be adjusted by compressing the yielding abutment to the
required degree, and forcing the nut against a collar, which prevents it revolving
until the abutment is caused to yield, and free the nut from the collar and allow the
nut to revolve.
Another arrangement for obtaining an adjustable feed is as follows; a casing is
formed with two trunnions and containing a loose bush through which the main
screw can pass, and between one end of this bush and the end of its casing, balls, or
their equivalent are placed as in the other arrangements. The loose bush is kept in
its place so as to be free to revolve around the axis of the main screw, and the
opposite end to that which is fitted with the balls, projects beyond the casing, and
is the part against which the nut bears. This end of the bush is made by preference
cup shaped, to give a good grip on the nut bearing against it. A projection on the

page_text: casing forms a stop to prevent a clamp on the nut revolving with the nut.
Instead of applying the break to the nut, it is better to apply it to the bush which
projects from the casing and against which the nut bears. The operation of this
arrangement is the same as in the first arrangement, but the nut is not enclosed
within the socket, and may be made in two parts suitable joined together and
commonly called a split nut.
When the nut is made in two parts commonly called a split nut, the following is
the manner I prefer to make it. One half of the nut is formed to serve as a guide
or box for the other half to slide hetween, and also hold a screw, which is made to
cause the two halves to close or separate from the main screw. One end of the screw
has a butterfly handle, and is held between collars on the box half of the nut, and the
other end is screwed and is screwed into the other half of the nut which slides in the
box half, so that when the screw is revolved one half the nut travels up or down
the screw, and slides inside the box half.
The two halves of the nut thus fitted together may be engaged with the main screw,
or disengaged therefrom as required.
To render this arrangement of split nut still more offective, especially when used
for machines without any arrangement for obtaining a variable feed, the two halves
thus fitted together, are placed in a socket or holder, constructed with a box with an
open side to receive the split nut, and a cylinder at each end of it to guide the main
screw, or the two cylinders are connected together by two sides or straps only,
between which the split nut is placed. When the split nut is placed between these
sides or in the box part above described, the main screw is passed through one of the
cylinders, then between the two halves of the split nut and finally through the other
cylinder.
To cause cach half of the nut to engage with, or disengage from the main screw,
when the screw actuating them is revolved, there is a peg or set bolt, secured into one
side of the box part of the socket, or one of the side straps, with its inner end passing
through a slot in the box part of the nut and entering into a recess in the half which
slides within it.
This slot and recess are such that they allow each half of the nut to travel the
required distance to clear the screw, and are prevented from going beyond the
desired distance by the set screw or peg. If one half of the nut clears the main
screw first and reaches its limit of travel, it then forms an abutment for the screw by
which they are moved, to force the other half clear of the main screw also.
This arrangement is applicable as described, to be used in combination with the
abutment with balls, described above, for obtaining a variable feed, in which case one
of the cylinders at the end of the socket bears against the projecting bush the cup
shaped end.
When used without any arrangement for obtaining a variable feed, a trunnion
projects from each side of the socket, for hanging it to the standard, and when used
for that class of machine known as a ratchet, one of the cylinders at each end of the
socket is secured to the tube which forms a covering for the screw, and takes the thrust
of the machine when in use.
In combination with these arrangements of adjustable feeds and split nuts, I employ
a sliding socket to connect the main screw to the drill. The main screw end and the
drill end, which are to be coupled together, are made straight, and any convenient
section, but not necessarily both of the same section, one with sufficient length to
receive the whole of the socket and the other to receive half of it. The socket is made
with a hole through it which will admit both the end of the drill and the screw,
whether of the same section or not, and so that neither of them can turn on its axis
without the other, when the coupling is on both of them.. When coupled together, the
ends of the screw and drill meet about midway in the socket, & the socket is there
secured by means of a set screw. When it is necessary to uncouple them, the sliding
socket is slid its whole length upon the end of the drill, or screw, whichever is made to
receive its whole length, and it is then clear of the junction of the screw and drill and

page_text: allows the screw to be reversed and the drill changed. When two handles are used
for driving the main screw, the square part of each end of the screw is made long
enough to receive one handle, and one half of the sliding socket.
A coupling socket is also formed for readily disengaging the drill from the main
screw, by forming it with a hole one half its length, to fit on the square part on cach
end of the main screw, and a recess at the other half of its length to receive drill end,
or the recess may be made to receive the square part at the end of the main screw, and
the hole to fit on the drill end.
A sliding hoop is then made to fit and slide on the outside of the coupling, and
made about equal in length to one half the length of the coupling socket, and when
slid on to the end which has the recess, closes the recess and forms a perfect socket for
coupling the drill and screw. When it is necessary to uncouple them, the hoop is
slid off the recess and the screw is free to be separated from the drill and reversed as
before described.
Instead of the hoop to slide on the outside of the socket, the ratchet handle used for
driving the main screw, may be made to slide on the socket and answer the same
purpose as the hoop.
The sliding socket and ratchet handle may be combined in one, to save space and
parts.
The improved construction of the standard which forms another part of this inven-
tion, consists of the improved sections of steel or iron employed, and the mode of
connecting the parts of the standard by a sliding clip to render the standard telescopic
without in any way interfering with the notched part, which is made to receive the
trunnions on the nut socket or carries.
The standard, is constructed mainly of two parts which are made of different sections
of steel or iron, so that one part may slide lengthwise upon the other, part of one
section embracing part of the other or by a clip attached to one and embracing a part
of the other.
1
Each and all of these methods, forming a sliding connection which does not at any
part of the length of the standard, interfere with the notches cut to receive the
trunnions on the nut or nut socket.
This cannot be done with the standards at present in use, and made of the sections
of steel or iron as now used.
The two sliding parts of the standard are provided with a suitable means for securing
them at any part of their sliding capacity, and there is a screw at one end of the
standard for securing it in position in the usual manner.
When the conditions are such that a standard constructed as above described cannot
be fixed by reason of the distance between the roof and floor of the mine being too
great, or in open work where there is no roof, a standard is used which can be fixed
in the coal or substance to be bored, by means of a short hole bored into the material.
The standard is constructed with the end which is put into the short hole bored into
the material to be bored, capable of being expanded by means of a wedge actuated by
a screw, or fitted with expanding pieces to project out from the standard, and actuated
by a screw and rod. In each of these arrangements the standard is secured in the
hole by means of the end being expanded in the hole bored in the material, or by
expanding pieces projecting from the standard. Short spikes are made on the
expanding parts to give a good grip on the material.
At the reverse end to that which is secured in the short hole in the material, a
carriage is provided to receive the trunnions on the main screw, nut or nut socket,
and also serves as a connection to the two parts of the standard when made in
two parts.
It is preferred to made the standard of tubular form when in one piece, or of two
parts of semicircular section, when in two pieces, although other sections may be used,
especially and U sections.
A device is also provided for driving the main screw by means of gearing, and ono
or two handles.

page_text: This arrangement slips over the main screw, and is secured to the carriage, or main
screw nut, or both; a bevel wheel which fits on the main screw, and is connected
therewith by a sliding feather in a groove cut in the main screw, is actuated by
another bevel wheel on a spindle to which a handle is attached.
When two handles are used, another spindle is required with a pair of spur wheels,
and the handles are attached to the spindle on which one spur wheel is fixed, the
other spur wheel is fixed on the same spindle as one of the bevel wheels.
By these devices the operator is enabled to turn his handle when a hole is bored
close to the side, top, or bottom of the place.
Dal Lak
محمل
1000

page_text: 1 GEORGE WILLIAM ELLIOTT of Wharncliffe Villa, Meersbrook Bank, Sheffield,
Yorkshire, Mining and Mechanical Engineer 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 :--
.
In order to render the carrying out of this invention clearly understood, seven
sheets of drawings are annexed, in which like letters refer to like parts in each figure.
Sheet 1. Figs. 1 to 6 illustrato different arrangements for obtaining an adjustable feed
or rate of progression of the main screw through its nut, so arranged with balls at
each end of the nut, to allow the main screw to be turned end for end when the drills
are changed, and thus render it unnecessary to run the screw back its whole length
through the nut, which would be the case if balls were placed at one end of the nut
only, as in the arrangements illustrated on Sheet 2, Figs. 1 to 6. One of the improve-
ments in the nut, break-gear, and socket for holding them, is the manner of arranging
balls at each end of the nut so as to take the thirst, and by providing a rolling
contact, to reduce the friction between the nut and its abutments, below that of the
nut on its thread, to allow the nut to revolve with its screw. In Sheet 1. Figs. 1. 2 a
groove A is made at each end of the nut B, and its abutments C, for a path for the
balls D, and the halls D, are kept in their positions relative to each other by means of
a washer E pierced with a hole for each ball, and allowed to revolve freely around the
main screw F, as the balls D, roll in their paths A. By this means much fewer are
required than is the case when no pierced washer or cage is used.
The brake is arranged in two parts, a strap G, Sheet 1. Figs. 1. 2, and a block H,
sliding within it and forced together, to grip the nut B, by a screw 1, or a screw I
Figs. 3. & 4., and a pad or saddle J. between it and the nut B, may be used.
The socket K, Figs. 1. 2. for the nut B, is made like a tube, with a trunnion L, at
each side for hanging it to the standard. The hole through the tube is large enough
to admit freely the nut B, of the main-screw F, which is cylindrical in form, and after
the nut and brake arrangement has been inserted, each end of the socket K, is fitted
with a bush C, either screwed into it, or otherwise secured therein. The inner ends of
these bushes C, each form the abutment for each end of the nut B, and are grooved to
form the paths A, for the balls D, which are placed between the nut B, and its abut-
ments C. The internal diameter of these bushes C, is equal to the diameter of the
main screw F, and they form a guide for the main-screw F. One end only of the
socket K, Figs. 3. 4 may be left open to admit the nut B, and the other end M, to fit
the main-screw F so that a bush is required at one end only of the socket.
The chief advantage of making the socket K with a bush C, at one or both ends is,
that these bushes forin when screwed into the socket a ready means of adjusting the
fit of the nut and its abutments, which require a nice adjustment to make them work
properly.

page_text: There is an opening in the centre of the socket . Figs. 1. 2, at one side, between
the trunnions L, to admit of the insertion of the brake arrangement for the main nut B,
in one arrangement of it, and in another arrangement Figs. 3. 4, a recess for the pad J,
and boss for the screw Lis provided.
Instead of making the socket as above described, it may be constructed with two
tubes O Figs. 5. 6. for guiding the main screw F, connected together by two straps N,
which also have each a trunnion L, projecting from it to hang the socket K, to the
standard.
A
By having the two side-straps N, only, the inner ends of the two tubes O, can
readily be trued up at right angles to the axis of the main-screw, nut, and nut-socket,
to receive a plate P, of metal, with a groove A, to form the path for the balls D.
plate or cover Q, is provided for each of the open sides, to cover up the nut and its
fittings, one of the plates having provision made in it for the brake arrangement R,
as described for the tubular socket.
Instead of inserting the nut B, and the two plates B, and the balls D, between the
two side straps N, and then inserting the main-screw F, through the two tubes O, as is
necessary in this arrangement, one or both of the tubes O, may be made large enough
to allow the nut B, to pass through it and an inner bush after inserted, as described
in the arrangement for the tubular socket, Figs. 1. 2. 3. 4.
When this is done the plates P, having grooves A, for the balls, are not required.
Another arrangement for obtaining an adjustable feed but which only permits one
end of the main-screw to be used to hold the drill, Sheet 2. Figs. 1. 2. 3. 4. 5. 6, is
by providing a casing K, for the nut B, and balls D, or their equivalent, at one end of
the nut B only, to reduce the friction between the end of the nut B, and its abutments C,
below the friction of the nut B, on the thread of the screw F.
The balls D, are placed between the end of the nut B, and a cap or ring P, which
bears against the end of a strong spring C, or yielding substance placed between this
ring P, and the end of the casing K.
An adjustable stop G, prevents the nut B, from revolving until the pressure of the
drill compresses the yielding abutment C, of the nut B, to the required degree, when
the nut B is freed from the stop G, and is allowed to revolve with screw F, and
the screw F, ceases to progress through the nut B until the pressure on the drill is
reduced to allow the yielding abutment C, to again bring the nut B in contact with
the stop G.
The feed may be also adjusted by compressing the yielding abutment C. Figs. 3. 4,
to the required degree, by means of the bush I, forcing the nut B against a collar G,
which prevents it revolving until the abutment C, is caused to yield and free the nut B,
from the collar G, and allow it to revolve.
Another arrangement for obtaining an adjustable feed is as follows, Sheet 2.
Figs. 5. 6.
A casing K, is formed with two trunnions L, and containing a loose bush P,
through which the main-screw F can pass, and between one end of this bush.P
and the end of its casing K, balls D, or their equivalent, are placed as in the other
arrangements.
The loose bush P is kept in its place so as to be free to revolve around the axis of
the main-screw F, and the opposite end to that which is fitted with the balls, projects
beyond the casing K, and is the part against which the nut B bears.
This end of the bush P, is made by preference cup shaped to give a good grip on the
nut B bearing against it..
A projection on the casing forms a stop to prevent a clamp on the nut revolving
with the nut, but instead of applying the brake H to the nut, it is better to apply it to
the bush P, which projects from the casing K, and against which the nut bears, as shown
in Figs. 5. 6.
The operation of this arrangement is the same as in the first arrangement but the
nut B is not enclosed within the socket K and may be made in two parts suitably
joined together and commonly called a split nut.
When the nut is made in two parts the following is the manner I prefer to make it.

page_text: One half of the nut A Sheet 3. Figs. 1. 2 is formed to serve as a guide or box
for the other half B to slide between, and also hold a screw C, which is made to
cause the two halves to close or separate from the main-screw F. One end of the
screw C, has a butterfly handle D, and is held between collars E on the box half
of the nut A, and the other end is screwed into the other half of the nut B, which
slides in the box half A, so that when the screw is revolved, one half of the nut B,
travels up or down the screw C, and slides inside the box half A. The two halves
of the nut A. B, thus fitted together, may be engaged with the main-screw F, or
disengaged therefrom as required.
To render this arrangement of split nut still more effective, especially when used
for machines without any arrangement for obtaining a variable feed, the two halves
thus fitted together are placed in a socket K, constructed with a box E with an
open side to receive the split-nut A. B, and a cylinder H at each end of it to
guide the main screw F, or, the two cylinders H, are connected together by two
sides or straps only between which the split-nut A B is placed. When the split
nut A B is placed between these sides or in the box E, the main-screw F, is
passed through one of the cylinders H, then between the two halves of the split
nut A B, and finally through the other cylinder H.
To cause each half of the split-nut A, B, to engage with or disengage from the
main-screw F, when the screw C, actuating them, is revolved, there is a peg or
set bolt M, secured into one side of the box part of the socket E or one of the
sides or straps, with its inner end passing through a slot N, in the box part of the
nut A, and entering into a recess U, in the half B, which slides within it. This
slot N, and recess O, are such that they allow each half of the nut to travel the
required distance to clear the screw F, and are prevented from going beyond the desired
distance, by the set screw or peg M."
If one half of the nut clears the main-screw first and reaches its limit of travel,
it then forms an abutment for the screw C, by which they are moved, to force the
other half clear of the main-screw F also. This arrangement is applicable as
described, to be used in combination with the abutment with balls described above,
and illustrated in sheet 2, Figs. 5. 6. for obtaining a variable feed, in which case
one of the cylinders H at the end of the socket K, bears against the projecting
bush P, with the cup-shaped end Sheet 2 Figs. 5. 6.
When used without any arrangement for obtaining a variable feed, a trunnion L
projects from each side of the socket K for hanging it to the standard, and when used
for thai class of machine known as a ratchett, one of the cylinders H at each end of the
socket K, is secured to the tube which forms a covering for the screw, and takes the
thrust of the machine when in use.
In combination with these arrangements of adjustable feeds and split-nuts, I employ
a sliding socket A, Sheet 4. Figs. 1. 2, to connect the main-screw F to the drill D.
The main screw end F, and the drill end D, which are coupled together, are made
straight, and any convenient section, but not necessarily both the same section, one
with sufficient length to receive the whole of the socket A and the other to receive
half of it: The socket A is made with a hole C, Fig. 2. through it which will
admit both the end of the drill or the screw whether of the same section or not, 4
and so that neither of them can turn on its axis without the other when the
coupling is on both of them.
When coupled together the ends of the screw F and
drill D, meet about midway in the socket A, and the socket A is there secured by
means of the set screw E.
When it is necessary to uncouple them the sliding socket A is slid its whole length
upon the end of the drill D, or screw F whichever is made to receive its whole
length. The drill end D, in the drawing is shown so prepared, and it is there clear of
the junction of the screw F and drill D and allows the screw F to be reversed and the
drill changed.
When two handles are used for driving the main screw F, the square part at each 5
end of the screw F is made long enough to receive one handle and one half of the
sliding socket A.

page_text: A coupling socket H, Sheet 4. Figs. 3. 4. is also formed for readily disengaging the
drill D, from the main-screw F, by forming it with a hole C, one half its length to fit
the square part on each end of the main-screw F, and a recess B at the other half of
its length to receive the drill end D, or the recess B may be made to receive the square
part of the end of the main-screw, and the hole to fit on the drill end D.
A sliding hoop J is then made to fit and slide on the outside of the coupling H and
made about equal in length to one half the length of the coupling H, and when slid
on the end which has the recess B, closes the recess B, and forms a perfect socket for
coupling the drill and screw. When it is necessary to uncouple them, the hoop Jis slid
off the recess B and the screw F is free to be separated from the drill D and reversed
as before described.
Instead of the hoop J to slide on the outside of the socket H the ratchett handle, K.,
Sheet 3., Figs. 6. 7. 8. used for driving the main-screw F may be made to slide on the
socket H and answer the same purpose as the hoop J, in Sheet 4. Figs. 3. 4.
The sliding socket and ratchett handle or handles may be combined in one as shown
in sheet 3 Figs. 3. 4. 5 and Sheet 4. Figs. 5. 6. to save space and parts.
The improved construction of the standard which forms another part of this
invention consists of the improved sections of steel or iron employed and the mode of
connecting the parts of the standard by a sliding clip to render the standard telescopic
without in any way interfereing with the notched parts which are made to receive the
trunnions on the nut socket or carrier.
The standard Sheet 5. Figs. 1. 2. 3. is constructed mainly of two parts A B, which
are made of different sections of steel or iron, so that one part B; may slide lengthwise
upon the other part A, part of one section B, embracing part of the other
section A, Fig. 4. or one section being connected with the other by a clip formed by a
portion of one section being turned to clip the other, as in Fig. 5. where the
U section B may have a portion at one end turned in, to clip the part A, as shown
in Fig. 4. Or by a clip C, Fig. 6. 7. 8. 9., attached to one B, and embracing a portion
of the other A.
Each and all of these methods forming a sliding connection which does not at any
part of the length of the standard, interfere with the notches N, cut to receive the
trunnions on the nut or nut socket.
This cannot be done with the standard at present in use, and made of sections of
steel or iron as now used. The two sliding parts of the standard A & B, are provided
with a suitable means K, for securing them at any part of their sliding capacity. This
arrangement K is a gibbed wedge, which forces the parts A & B firmly together so
that they will not slip when fixed, and can be instantly freed when required. There is
a screw S at one end of the standard by which it is secured in position in the usual
manner.
When the conditions are such that a standard constructed as above described
cannot be fixed by reason of the distance between the roof and floor of the mine being
too great, or in open work where there is no roof, a standard Sheet 6. Figs. 1. 2. 3 is
used which can be fixed in the coal or substance to be bored, by means of a short hole
bored into the material.
The standard is constructed with the end A to put into the short hole bored into
the material to be bored capable of being expanded by means of a wedge B
Figs. 1. 2. 7. 9. 10. 12, actuated by a screw C, or fitted with expanding pieces D
Figs. 3. 6. 13. 15, actuated by a screw C, and rod E. In each of these arrangements
the standard is secured in the hole by means of the end A being expanded in the short
hole bored in the material, or by expanding pieces projecting from the standard.
Short spikes K, are made on the expanding parts to give them a good grip on
the material.
At the reverse end to that which is secured in the short hole in the material,
a carriage N, is provided to receive the trunnions on the main screw nut, or
nut, socket, and also serves as a connection to the two parts of the standard O. F.
when made in two parts.
It is preferable to make the standard of tubular form when in one piece

page_text: Figs. 3. 6. 13. 14. 15 or of two parts of semi-circular section, Figs. 1. 4: 7. 8. 9.
when in two pieces, although other sections may be used, especially T & U sections.
Figs. 2. 5. 10. 11. 12.
Figs. 8. 11. 14 are sections through the standards on the line S. T.
are sections through the standards on the line Q. R. Figs. 7. 10.
the bottom ends of the standards. Figs. 4. 5. 6 are views of the
standards.
Figs. 9. 12. 15
13 are views of
top ends of the
A device is also provided for driving the main-screw by means of- gearing, and one
or two handles.
This arrangement, Sheet 7. Figs. 1. 2 slips over the main-screw, and is secured to
the carriage N, main-screw-nut A, or both.
A bevel wheel B, which fits on the main-screw F and is connected therewith by a
sliding feather C, in a groove D, cut in the main-screw F, is actuated by another
bevel wheel E on a spindle H to which a handle J is attached. When two handles
are used, another spindle is required with a pair of spur wheels, and the handles are
attached to the spindle on which one spur wheel is fixed, the other spur wheel is fixed
on the same spindle as one of the bevel wheels.
By these devices the operator is enabled to turn his handle when a hole is bored
close to the side, top, or bottom of the places.
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―
1st. The arrangements for obtaining a variable progression of the main-screw of
Rock drills through its nut as herein described and illustrated, upon sheets 1. 2.
2nd. The arrangement of balls at each end of the nut of the main-screw of
rock-drills, with perforated washers to retain them in their respective places, for
the purpose, and in the manner herein described, and illustrated upon sheet 1.
3rd. The arrangement of split nut for rock drills as herein described, and illustrated
on sheet 3.
4th. The arrangement of sliding sockets and handles for coupling the main-screw
and drill of rock-drills as herein described, and illustrated on Sheets 3. 4.
5th. The manner of making telescopic standards of rock drills with the various
sections of steel or iron as herein described, and illustrated, on sheet 5.
6th. The manner of constructing standards of rock drills for fixing in a short hole,
us herein described, and illustrated on Sheet 6th.
7th. The arrangement of gearing for driving the main-screw of rock-drills, as horein
described, and illustrated on Sheet 7.
11121 Ja of Al 1000