Improvement in the Feed Arrangement of Lathes.
Year: 1899

page_text: Date of Application, 8th May, 1899-Accepted, 8th July, 1899
COMPLETE SPECIFICATION.
Improvement in the Feed Arrangement of Lathes.
ROBERT LANG and WILLIAM BIGGAR LANG, of the Firm of John Lang & Sons,
Lathe Manufacturers and Special Machine Tool-Makers, Mary Street, John-
stone, near Glasgow, 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:-
The object of this invention is to provide a combination of two sets of gears
to give a number of slow feeds and a number of fast feeds any one of which may
be had by the use of two handles without changing any gears or stopping the
lathe. It is a usual practice to provide three or four feeds on a lathe which can
be changed from one to the other by means of a handle. We propose to add
another handle and two pairs of gears which will then allow three or four or
any number of slow feeds for drilling out of the solid and three or four or any
number of fast feeds for boring out cored or roughed out holes and for turning
The advantage of this over the present system will be a greater number of feeds.
Fig. 1 is a front elevation of part of a bed of lathe showing the two handles.
Fig. 2 is an end elevation of bed of lathe showing the position of shafts M
and. G.
Fig. 3 is a sectional plan of part of bed on the line A B.
Fig. 4 is an end view of wheel D showing slots in hole into which the feather F
is moved when wheel is wanted to drive the hollow shaft E. The holes of
wheels C I J K L are similar to the hole in D.
C and D) are a wheel and pinion which are driven from the main spindle of
lathe by a corresponding pinion and wheel. Either C or D can be made to
drive the hollow shaft E by means of a sliding feather F. This feather is moved
along into either C or D by the small shaft G. When the feather F is in the
position in which it is shown neither of the wheels C or D can drive the hollow
shaft. The reason for this is that a round part is turned in the holes of C and D)
the full diameter of the feather F so that when the feather is in its present position
it simply stands stationary although both wheels may be revolving. Whenever
the feather is moved either to right or left however, it engages in the slots of
the holes, hence it is made to drive the hollow shaft E. Thus it will be seen
that C and D cannot possibly be engaged feeding at one time. The shaft G is
moved along by the handle H which is connected to it by a lever. Again the
hollow shaft E can be made to drive the shaft M through wheels I J K L or
any number which may be desired. These wheels are driven by the sliding
key 0, which may be moved into any of them by the small shaft N. We would
here point out that the feather O cannot possibly be engaged in any two feed
wheels at the same time. When in the position shown in the drawing it would
simply revolve without feeding, as there is a part turned out of wheels the full
diameter of the feather. This allows the feather to revolve without feeding
when in its present position or when it is exactly between any of the wheels
IJK L. When however the feather is exactly in the middle of any one of

page_text: the wheels I J K L it then drives it by means of the slots as shown in the hole
of wheel on Fig. 4. The different positions can be got very easily by moving
either handle P or H opposite the small circles shown on the quadrant patches
on Fig. 1. Some of these circles have figures indicating the feed and some have
the figure O indicating that the feather is between the wheels and hence giving
no feed when handle is opposite such a mark. From this it will be understood
that each time the feed is being altered it is first stopped by moving a feather
into a circular space, and then restarted quicker or slower by moving the said
feather further on into a slotted part of a wheel. The shaft N is moved along by
the handle P which is connected to it by a lever. It may be here stated that
the shaft N is entirely independent of the shaft G; although they slide in the
same hole the one, G, which extends from the line Q to the line R is moved
only by the handle H and the other, N, which extends from the line S to the
line T is moved only by the handle P. The shaft G is connected to the
washers by pins U and in the hollow shaft E there are oblong slots to allow
these pins being moved endways when altering the feather F. The shaft M
drives the feed motion of the saddle of lathe by worm gearing in the usual way.
Thus we can have three or four or any number of feeds by means of such wheels
as I J K L when driving through wheel C and by movement of handle H we
can have a corresponding number of feeds much faster when driving through D.
Having now described and ascertained the nature of our said invention and
in what manner it is to be performed we declare that what we claim is:-
To provide a combination of two sets of gears to give a number of slow' feeds
and a number of fast feeds any one of which may be had by the use of two
handles without changing any gears or stopping the lathe.
Total this Cith dur of V 1800
ROBERT LANG.
WILLIAM BIGGAR LANG.