Improvements in Slotting and similar Machines.
Year: 1892

page_text: Date of Application, 6th May, 1892-Accepted, 11th June, 1892
COMPLETE SPECIFICATION.
Improvements in Slotting and similar Machines.
I, GOTTLOB FRIEDRICH GROTZ of Bahnhofstrasse, Bissingen in the Kingdom
of Wurtemberg, and German Empire, 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 machines for cutting key-ways and similar slots. In a
machine constructed to embody these improvements the tool. is. held by a tool
holder attached to a vertically moveable slide contained within a laterally moveable
slide or carriage, the latter slide being operated by a rack and pinion or other
suitable device to cut the slot. The vertical slide which holds the tool is alternately
raised and lowered during the operation of the machine by two fixed stops engaging
with a suitable cam, thus lowering the tool into the slot at the commencement of
the stroke and raising it at its conclusion.
I will now particularly describe my invention with reference to the accompanying
drawings in which-
Figure 1 is an elevation of the machine in position for cutting a keyway in the
middle of a shaft ;
Figure 2 is a plan; and
Figure 3 a cross section.
The laterally moveable slide B which is moved along the bed of the machine A
by means of a rack and pinion or by other suitable means, is furnished with a
vertical slide C the lower end of which carries a chuck or tool holder d.
At the commencement of working, the slide C and its tool holder and tool_are
automatically moved downwards, the tool cutting into the shaft or other part E to
be operated upon. The cut or slot commences with a slight angle continues for
some distance parallel with the axis of the shaft and finally rises and leaves the
slot at about the same angle as that with which it commenced.
The automatic rising and falling of the slide C and its tool holder, is effected
by the circular cam f which is mounted so as to be capable of partial rotation in
a bridge secured to the laterally moving slide B. At the top and bottom
respectively off and secured to the slide C are two similar cams f³ ³. As the
slide B is moved alternately to and fro along the bed A of the machine, two
projections gg fixed upon the cam f¹ engage alternately and respectively with the
two adjustably fixed stops or trip pieces h². A quarter revolution is thus
imparted to fupon the one movement of the slide B, through the projection g¹
engaging with the stop h', and a quarter revolution in the reverse direction when
the projection g' engages with the stop 2 upon the return movement of the slide B.
These partial revolutions of the cam f' cause the corresponding cams f³ to rise
and fall together with the slide C to which they are attached.
Figure 1 illustrates the positions of the cams when the slide C is lowered, while
Figure 1 shews the positions of the cams with the slide raised.
In order to prevent the cam f¹ being turned at the wrong part of the stroke
when repassing either of the stops, the projection gl or both the projections may
be arranged in the form of a spring latch so as to move past the stops during the
backward motion of the slide.
The two stops are adjustable upon the bed so that they can be set any
desired distance apart, to regulate the length of the key way or slot.
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,―
1. In a slotting machine apparatus for automatically lowering and lifting the

page_text: tool holder at the beginning and end of each cut; constructed arranged and
operated substantially as hereinbefore described and as illustrated by the accom-
panying drawings.
2. A slotting machine in which the tool holder is automatically operated to begin
the cut at a small angle, to finish the cut at a similar reverse angle, and finally to
be returned to the starting point, substantially as and by the means hereinbefore
described and as illustrated by the accompanying drawings.
Dated this 4th day of May A.D. 1892.
WILLIAM E. HEYS,
Agent for the Applicant.