Improvements in Lathes.
Year: 1898

page_text: Date of Application, 16th Feb., 1898-Accepted, 26th Mar., 1898
Improvements in Lathes.
We, SALOMON PERLE, of Goldeneradegasse 21, Merchant, EUGEN PERLE, of
Schwertstrasse 6, Merchant, and WILHELM BUTTERMILCH, of Neumarkt 8,
Engineer, all in Breslau, in the German Empire, 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 lathes and its object is to provide means whereby
screws may be cut of any pitch without the use of change wheels.
In carrying these improvements into effect a suitable screw carrying a movable nut
is mounted upon any convenient part of the lathe and the motion of the nut is
transmitted to the slide rest through an adjustable series of levers and links.
The accompanying drawings illustrate two forms of the devices which may be
employed.
As shewn in Figure 1 a screw 1 is mounted so as to be rotated by the lathe
spindle or other convenient part. It is furnished with a nut 3 which moves in one
direction or the other along the screw 1 according to the direction of rotation of
the latter. The nut is connected by a link 4 with one arm of a lever 2 which is
pivotted at 8 to the frame of the lathe. This lever extends past the pivot and both
its arms are slotted. From one of the arms a link 5 extends to the arm or lever 6 which
is adjustably fixed to the sliding block 7 capable of reciprocating in the slides 9. A
stud 11 at one end of the link and a similar stud at the other end provide means
by which the link may be attached to the levers. 12 is a rod or shaft secured to
the block 7 and connected to the slide rest 10.
As soon as the screw 1 commences to rotate the lever 2 begins to turn on its
pivot and moves the rest 10 in one direction or the other along the lathe bed. The
rate of movement will depend upon the position of the link 5 upon the lever 2, the
movement of the slide rest being slow when the end of the lever is moved to
occupy a position near to the fulcrum of the lever, and more quick the further the
end of the link is moved along the arm of the lever away from the fulcrum.
It will thus be seen that screws of different pitches may be cut in the same lathe
without change by simply varying the position of the link 5 upon the lever 2.
For cutting left hand screws or taking a cut in the reverse direction the link 5 is
removed from the lever 2 and the arm 6: the set screw of the latter is released,
and it is pushed down so as to occupy a lower position where it is refixed by the
The link 5 is then re-combined with them, now, however, occupying a
position below the fulcrum of the lever. Any motion given to the nut 3 is thus
imparted in a reverse direction to the slide rest 10. The arms of the lever 2 may be
graduated if desired so as to facilitate the adjustment of the link 5.
screw.
Figures 2 and 3 illustrate a modified form of device by means of which the
movement of the rest can be easily effected in either direction. Two screws 13
and 14 are mounted upon the lathe and are capable of moving the nut 16, one in
one direction and one in the other. This nut may be thrown in or out of gear with
either of the screws as desired, according to the motion desired in the rest. The

page_text: other devices and appliances are the same, with the exceptions that the lever 6
may be pivotted at its lower end to the slides and engage with a stud fixed to the
block, and that there is no necessity to extend the lever 2 beyond its fulcrum 8.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed, we declare that what we
claim is :-
1. In a screw cutting lathe, the combination with a screw provided with a travelling
nut, of adjustable levers and other devices by means of which motion may be
conveyed from the nut to the slide rest, substantially as and for the purpose
herein before described and as illustrated by the accompanying drawings.
2. In a screw cutting lathe, levers or the like by means of which motion at
any desired speed may be communicated to the slide rest without the use of change
wheels, constructed and arranged substantially as herein before described and as
illustrated by the accompanying drawings.
3. In a screw cutting lathe, the herein before described mechanism for ac tuating
a slide rest at any desired speed, constructed and arranged as set forth and as
illustrated by the accompanying drawings.
Dated this 15th day of February A.D. 1898.
W.
E. HEYS & SON,
Agents for the Applicants.