Improvements in Tool Holders for Metal Working Machines.
Year: 1898

page_text: Date of Application, 15th Apr., 1898-Accepted, 19th Nov., 1898
COMPLETE SPECIFICATION.
Improvements in Tool Holders for Metal Working Machines.
I, JOACHIM JOHANNES DAHL, of 110, Hafenstrasse, Hamburg, in the Empire of
Germany, 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 tool holders for metal working machines, and particularly
for planing machines, which are so arranged that a sleeve or lining for holding the
tool can be shifted or put into a socket of the tool holder proper which is fixed to the
machine, which socket can be turned through an angle of 180° at the reversal of
the stroke, during the working of the machine, that is to say the backward and
forward movement of the table by suitable means, as, for example by a screw,
eccentric, or the like, for the purpose of obtaining a uniform cut during such back-
ward and forward movement of the work.
The invention is illustrated in the accompanying drawing in which
Figure 1 shows a front view of a metal planing machine with a tool holder made
in accordance with this invention.
Figure 2 shows a front view of the tool holder drawn to a larger scale.
Figure 3 shows a similar view of the tool holder, but partly in section; the
cutting tool and the socket containing it being turned through an angle of 180°.
Figure 4 is a vertical section on line 4-4 (Figure 2).
Figures 5 and 6 are horizontal sections on lines 5-5 and 6-6 of (Figures 2 and 3)
respectively.
Similar letters of reference indicate corresponding parts in all the figures of the
drawing.
The casing a is arranged on a horizontal pivot a¹ on the part A of the planing
machine and is adapted to be fixed by clamping screws a³ arranged in the slots a².
Within this casing is a socket b, which is held by nuts 61 and 62, the upper end of
the said socket being provided with a toothwheel 63, and the lower end with two
diametrically arranged notches or grooves 64. The socket 6 which is rotatable in
the casing a is secured in one or the other of its extreme positions by a spring
bolt c which fits into the grooves 64, the said bolt being suitably arranged in a
projection on the casing a, and connected with a coupling lever c¹ pivoted at c² to
the casing a, and adapted to be operated by a [cam face ¹ on rope pulley k. The
central opening of the socket b is widened at the lower part for the purpose of
receiving a sleeve d, likewise provided with a central aperture. The sleeve dis
provided in a recess at its lower end with a block d² which can be turned upwards
upon a pin d¹, in which block the tool e, e¹ can be clamped in the known manner
by a clamping screw d³. To prevent its falling out, the sleeve d is secured by two.
screw bolts
which pass through it, and which are screwed into suitable slide
pieces f¹¹, preferably of T shape, situated in a groove of the socket b. The
opening of the socket b is somewhat larger in the direction of the feed movement
(see Figure 3) so as to allow of a parallel movement being imparted to the sleeve d
of the socket 6, during the working of the machine, and therefore to the tool itself
a movement differential with respect to the feed motion. This. movement can be
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page_text: effected by suitable means, for instance, by an endless screw g fixed in the socket b,
which takes into suitable teeth cut in the sleeve d (Figure 4). To facilitate access
to the adjusting screw g, the casing is provided with two suitable recesses or
gaps a¹.
The adjustability of the tool above described, in the pivotted socket during the
working of the machine is of great importance, as it is possible only by this to
obtain in the forward as well as in the backward movement of the work a uniform
cut, as well as to take off an equally thick shaving as the tool can never be so exactly
sharpened and set that it will always cut uniformly even after being turned
through 180°.
The movement or reversal of the tool and also of the casing carrying the said
tool and the sleeve to the extent of 180° for allowing the forward or backward
movement of the work W (Figure 1), which movement takes place during the change
of stroke of the table T, is effected in the following manner.
A toothed segment i which can be rotated on the axis secured to the casing a
engages with the toothed wheel 63, and turns the said wheel, and with it the tool e e¹
through an angle of 180° at every movement from the one end position (Figure 2)
to the other (Figure 3), and vice versa. The segment is turned by a rope
pulley connected with it, which pulley is turned in one or other direction by two
ropes m and m¹ conducted over suitable guide-rollers and weighted with a weight l¹.
The alternate tightening and loosening of the two ropes m and m¹ is effected
simultaneously at the end of each stroke of the belt fork which shifts the
bels and n from the loose pulleys o to the fixed pulley o', on which fork the free
ends of the ropes are fixed at p said ropes passing over the fixed lower pulleys l.
The shifting of the belt fork p is effected by a horizontal rod q, which is worked in
the known manner by a suitable lever rod or even by hand.
1
The coupling of the segment i and the rope pulley has in both directions a
certain lost motion, which serves to transpose the lever c¹, or to release the spring
bolt c to set free the socket b, said bolt being operated by means of the cam
face acting on a roller on the end of the lever c¹ (see Fig. 4). After the
rotation of the socket b, or at the end of the turning motion of the rope pulley k and
the segment i, the spring bolt c springs again into the groove 6* opposite to it, so as
t' hold the socket during the cutting operation.
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:-
A tool-holder for metal working machines, distinguished by a special sleeve for
holding the tool, which sleeve is fitted in the socket of the tool-holder casing, which
latter can be turned at each reversal of stroke through an angle of 180°, the sleeve
being adapted to be moved within the casing by means of adjusting screws or the
like in the direction of the feeding motion so as to regulate the putting in of the
tool also while working, for the purpose of obtaining a uniform cut by the forward
and backward movement of the work.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.