Improvements in Turning Lathes.
Year: 1893

page_text: Date of Application, 8th May, 1893
Complete Specification Left, 16th May, 1893-Accepted, 22nd July, 1893
PROVISIONAL SPECIFICATION.
Improvements in Turning Lathes.
I, FRIEDRICH SCHOTZ of Neueburg No. 12, Altona in the German Empire,
Electrician, do hereby declare the nature of this invention to be as follows:-
This invention has reference to improvements in turning lathes adapted to be
operated by means of electro motors. In a lathe constructed according to this
invention the electro motive power is not transmitted to the lathe spindle by means
of a strap as heretofore but the electro motor is arranged to drive the spindle direct,
for which purpose it is arranged within the head stock in the position usually
occupied by the speed pulleys.
The accompanying drawings illustrate the head stock of a turning lathe con-
structed with an electric motor according to this invention; the lathe shown is
provided with an ordinary arrangement of slow speed gearing and the cutting tool
is to be supported by hand, but it will be obvious that the invention is applicable
also to lathes provided with leading screws for operating slide rests.
Fig. 1 is a side elevation,
Fig. 2 a plan; and
Fig. 3 a section on line A B Fig. 1 of the combined head stock and electro
motor.
In the cheeks or brackets a of the head stock b is arranged in the ordinary manner
the spindle c. This spindle carries a toothed wheel d and has loosely mounted
therean an armature securely connected with a disc or pulley g which is adapted
to be connected with the toothed wheel d by means of a bolt and nut h in the usual
manner. This armaturefis arranged between the poles of a field magnet i which
is arranged within the head stock and which may be provided with two or more
windings one or more of which can be used at will. Just outside the field magnet
is arranged the collector k which is connected with the armature and arranged to
slide in contact with the brushes . These brushes are secured on or in supports or
holders m carried on the bridge n provided on the left hand bearing or bracket of
the head stock. Between the bridge and the collector is situated a small toothed
wheel o which is rigidly connected with said collector and adapted to be thrown
into gear with a larger toothed wheel p mounted on the laterally adjustable shaft
When this engagement takes place, another small wheel r situated on the same shaft
engages with the toothed wheel d mentioned above, the nut h having been previously
loosened as well understood.
9.
According as the electro-motor is connected with the spindle direct or drives it
through the medium of the intermediate gearing the speed at which the spindle
revolves will necessarily vary. To enable a wide range of slight variations to be
made as required (which the employment of the ordinary speed pulleys permits)
resistances may be inserted into the electrical circuit so as to reduce the speed of
the armature when desired.
By changing the direction in which the current is passed through the armature
or field the spindle c can be caused to turn either from right to left or from left to
right as may be desired.
Dated thin 9th day of M1903

page_text: COMPLETE SPECIFICATION.
Improvements in Turning Lathes.
1, FRIEDRICH SCHOTZ of Neueburg No. 12, Altona, in the German Empire,
Electrician, 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 has reference to improvements in turning lathes adapted to be
operated by means of electro motors.
In a lathe constructed according to this invention the electro motive power is not
transmitted to the lathe spindle by means of a strap as heretofore but the electric
motor is arranged to drive the spindle direct for which purpose it is arranged
within the head stock in the position usually occupied by the speed pulleys.
The drawings filed with my Provisional Specification illustrate the head stock
of a turning lathe constructed with an electric motor according to this invention;
the lathe shown is provided with an ordinary arrangement of slow speed gearing
and the cutting tool is to be supported by hand but it will be obvious that the
invention is applicable also to lathes provided with leading screws for operating
slide rests.
Fig. 1 is a side elevation ;
Fig. 2 a plan, and
Fig. 3 a section on line A B Fig. 1 of the combined head stock and electric
motor.
g
In the cheeks or brackets a of the head stock b is arranged in the ordinary
manner the spindle c. This spindle carries a toothed wheel d and has loosely
mounted thereon an armature securely connected with a disc or pulley 9 which is
adapted to be connected with the toothed wheel d by means of a bolt and nut h in
the usual manner. This armature f is arranged between the poles of a field
magnet which is arranged within the head stock. Just outside the field magnet
is arranged the collector k which is connected with the armature and arranged to
slide in contact with the brushes . These brushes are secured on or in supports or
holders m carried on the bridge n provided on the left hand bearing or bracket of
the head stock. Between the bridge and the collector is situated a small toothed
wheel o which is rigidly connected with said collector and adapted to be thrown
into gear with a larger toothed wheel p mounted on the laterally adjustable shaft
When this engagement takes place, another small wheel r situated on the same shaft
engages with the toothed wheel d mentioned above, the nut h having been
previously loosened as well understood.
2.
According as the electro-motor is connected with the spindle direct or drives it
through the medium of the intermediate gearing the speed at which the spindle
revolves will necessarily vary. To enable a wide range of slight variations to be
made as required (which the employment of the ordinary speed pulleys permits)
resistances may be inserted into the electrical circuit so as to reduce the speed of
the armature when desired.
By changing the direction in which the current is passed through the armature
or field the spindle can be caused to turn either from right to left or from left to
right as may be desired.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed I declare that what I
claim is:
1. A turning lathe constructed with an electric motor the field magnet of which
is carried by the fixed head stock of the lathe and the armature f of which is carried
by the lathe spindle substantially as heroin desoxibed

page_text: 2. A turning lathe adapted to be operated by an electro motor constructed
arranged and operating substantially as described and shown.
Dated this 16th day of May 1893.
F. SCHOTZ,
By L. W., per F. B.