Improvements in Apparatus for Forming, Making, and Sharpening Star Bit and Chisel Drills for Mining Purposes and for Forging and Forming Articles in Metal.
Year: 1898

page_text: Date of Application, 3rd Aug., 1898
Complete Specification Left, 3rd May, 1809--Accepted, 3rd Aug., 1899
Improvements in Apparatus for Forming, Making, and Sharpening
Star Bit and Chisel Drills for Mining Purposes and for Forging
and Forming Articles in Metal.
A communication by GEORGE JOHNSTON, of Durban, in the Colony of Natal,
Engineer.
I, WILLIAM PHILLIPS THOMPSON, F.C.S., M.I.M.E., of the Agency for Foreign
Patent Solicitors, 6, Lord Street, Liverpool, and 6, Bank Street, Manchester, both
in the County of Lancaster, 118, New Street, Birmingham, in the County of
Warwick, and 322, High Holborn, in the County of Middlesex, Civil Engineer,
do hereby declare the nature of this invention to be as follows:-
The machine comprises a metal frame to which are attached four forked
brackets or guides extending the whole length of inside of frame. These guides
are quadrilaterally arranged and secured by pins to projectious cast on back end
of frame, the pins allowing the guides to have a small vertical and lateral move-
ment. At the front end of frame the guides rest on seatings, and for the purpose
of adjustment are secured by adjusting set screws. At the front end of frame
four levers are secured to the guides by suitable pins, the inside face of these
levers are eccentric in shape and can be so arranged that dies and cutters can
be fitted to them. The simultaneous movement of the levers backwards and
forwards, they being at right angles one with the other, causes them to open
and close to and from a common centre. The levers are connected to the nut
of the screw with adjustable connecting rods, and are actuated by the screw and
nut with suitable gearing.
-
The screw passes through the back end of the frame on the outside of which
it is secured by a pedestal block bolted against or cast to the frame. On the
outside end of the screw shaft a toothed wheel is keyed that receives motion from
a pinion keyed on to the counter or driven shaft.
To go more into detail, there are four levers which are actuated by a screw,
the nut of the screw having four arms which are attached to the levers by
connecting rods; these connecting rods have adjusting screws in conjunction with
other adjusting screws truly adjusting the levers. The arms of the nut slide
in the four guide bars which carry the four eccentric faced levers. The end
of the screw shaft is tapped to receive a collared stud, this stud is adjustable
and acts as a stop to the bars that are fed into the machine, one of the arms is
At the end
lengthened to which is attached the lever of the reversing gear.
of the screw shaft is keyed a toothed wheel which is actuated by the pinion, the
shaft of which may carry the driven pulleys. The reciprocating movement of
the screw is obtained by changing the belting from fast to loose pulleys.
A jet of water may be so arranged that when the article is formed the water.
jet plays on the face of the levers or dies during the period that the nut is
travelling to place the levers in position for the next operation.

page_text: When an article is to be formed or impressed on the four sides such as star
bit drills for mining purposes, the four levers are used. When an article, such
as chisel bits or drills, cold chisels, or any piece of metal, has to be formed or
impressed on two sides, the two levers are used, the other two not being required.
The method of working is as follows:-
Power is applied to pulleys or other gearing by any well known means, which
causes the screw shaft to rotate, the rotation of the screw causes the nut to
travel carrying the levers, backward and forward as the case may be. After the
levers have travelled the required distance, the reciprocating movement of the
screw caused by the change of belting on the pulleys rotate the screw in an
opposite direction. When the nut is at the end of the screw next the orifice or
opening where the metal is fed through, the levers are then open to receive the
metal. The travelling of the nut backwards takes or pulls the levers, thus closing
the levers simultaneously with a rolling motion on the object which is formed
and automatically ejected, the screw then rotates in the opposite direction and
the levers are opened ready for the next operation.
Dated this 2nd day of August 1898.
Improvements in Apparatus for Forming, Making, and Sharpening
Star Bit and Chisel Drills for Mining Purposes and for Forging
and Forming Articles in Metal.
A communication by GEORGE JOHNSTON, of Durban, in the Colony of Natal,
Engineer.
I, WILLIAM PHILLIPS THOMPSON, F.C.S., M.I.M.E., of the Agency for Foreign
Patent Solicitors, 6, Lord Street, Liverpool, and 6, Bank Street, Manchester, both
in the County of Lancaster, 118, New Street, Birmingham, in the County of
Warwick, and 322, High Holborn, in the County of Middlesex, Civil 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:-
This invention relates to apparatus for forming, making and sharpening, star
bit and chisel drills for mining purposes, and for forging and forming articles
in metal.
The machine comprises a metal frame to which are attached four forked
brackets or guides extending the whole length of inside of frame. These guides
are quadrilaterally arranged and secured by pins to projections cast on back end
of frame, the pins allowing the guides to have a small vertical and lateral move-
ment. At the front end of frame the guides rest on seatings, and for the purpose
of adjustment are secured by adjusting set screws. At the front end of frame
four levers are secured to the guides by suitable pins, the inside face of these
levers are eccentric in shape and can be so arranged that dies and cutters can
be fitted to them. The simultaneous movement of the levers backwards and
forwards, they being at right angles one with the other, causes them to open
and close to and from a common centre. The levers are connected to the nut
of the screw with adjustable connecting rods, and are actuated by the screw and
nut with suitable gearing.
The screw passes through the back end of the frame on the outside of which

page_text: it is secured by a pedestal block bolted against or cast to the frame. On the
outside end of the screw shaft a toothed wheel is keyed that receives motion from
a pinion keyed on to the counter or driven shaft.
The invention will be understood from the following description, reference
being had to the accompanying drawings, in which:
Figure 1 is a front clevation of the apparatus with one pair of dies only in
position;
Figure 2 a plan of the same;
Figure 3 an end view;
Figure 4 a diagrammatical view of a pair of the dies;
Figure 5 an end elevation of the screw nut with the four arms;
Figure 6 a detail view of the bars in which the dies are mounted.
Referring to these figures, A. are four arms or levers having dies a eccentrically
mounted on axes a¹ in the bars F. These axes are arranged at equidistant
intervals apart, so that they shall be at right angles to each other. The dies
being eccentric will when operated simultaneously converge and act to press the
article presented thereto on all four sides into the shape required, for example
that of a star bit. Fare bars between which the dies a are mounted, and which
act as guides for the dies, and also by slackening the set screws H these bars can
be adjusted longitudinally, to adjust the position of the dies. The die levers
are actuated by a screw B, the nut c of this screw having four arms C which are
respectively coupled to the levers A by connecting rods D. The connecting
rods D have adjusting screws E, which in conjunction with the adjusting
screws H, enable the dies to be truly adjusted. The arms C of the nut slide
between the bars F. One end of the screw shaft B is tapped to receive a collared
stud K. This stud is adjustable and acts as a stop to the article that is fed between
the dies into the machine at R. One of the arms C is lengthened as at L, to
which can be attached the lever of the reversing gear. On the other end of
the screw shaft B is screwed a spur wheel N which is actuated by the pinion O
on the shaft which carries the fast and loose pulleys P. The reversing of the
screw is obtained by shifting the driving belts by the belt forks. The dies may
be cooled from time to time by means of a jet of water, which may be so arranged
that when the article is formed, and the nut is travelling back to place the levers
in position for the next operation, this jet of water is injected onto the face of
the dies. Two pairs of dies are used when the article is required to be formed
or impressed on all four sides, such for instance as star bit drills for mining
purposes. For steel bits or drills, cold bit pieces etcetera, which have to be
impressed on two sides only, one pair of dies only is required, the other pair
being removed or disconnected.
Figure 4 for instance shows two dies A adapted to form a chisel drill, the chisel
point being formed by the projections a³, which meet on the completion of the
shaping as shown in dotted lines.
The mode of working is as follows:-
The piece of metal to be acted upon being placed between the dies, power
is applied to the pulleys or other gearing, which cause the screw shaft B to
rotate. The rotation of the screw causes the nut C to travel pulling the levers A
and so causing the dies to converge and gradually compress the article into the
shape required. After the levers have travelled the required distance, the move-
ment of the screw B is reversed by shifting the belts so that the open belt which
drove the fast pulley shall be shifted onto the loose one, and the crossed belt
will drive instead. This may be effected by hand, or automatically if desired.
This reversal of motion releases the compressed article, which is then removed,
and the operation is repeated. It will be seen therefore that when the nut C
is at one end of the screw B, the dies are separated to receive the article ready
for the next operation, while the movement of the nut towards the opposite end
of the screw pulls the levers, thus causing the dies to converge simultaneously
and press the article into the shape required.

page_text: ifaving now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed as communicated
to me by my foreign correspondent, I declare that what I claim is:-
1. An apparatus for forming, making and sharpening star bit and chisel
drills for mining purposes, and for forging and forming articles in metal, in
which there are dies so mounted on eccentric axes opposite each other, in one or
more pairs, that when operated they shall simultaneously converge and act to
press or squeeze the article presented between them into the shape required,
substantially as described.
2. In an apparatus for forming, making, and sharpening star bit and chisel
drills for mining purposes and for forging and forming articles in metal, the com-
bination of the dies a, the arms or levers A formed on or rigidly attached
thereto, the rotary screw B, and nut thereon, and the connecting rods D
coupling the said nut to the ends of the die arms in such a manner that as the
screw is turned by the arms or levers, all the respective dies are simultaneously
caused to converge, and press the article into the shape required, substantially
as described.
3. In an apparatus of the kind described mounting the dies eccentrically on
axes in bars F, which act as guides for the dies, and by means of longitudinal
adjustment enable the position of the said dies to be adjusted substantially
as set forth.
4. An apparatus constructed substantially as described in reference to the
accompanying drawings, and operated as and for the purpose specified.
Dated this 2nd day of May 1899.
WM. P. THOMPSON & Co.,
Agents.