Note: Descriptions are shown in the official language in which they were submitted.
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The present invention relates to a shaping (planing,
routing) head having interchangeable reversible cutters, the
projecting outer cutting edges of which constitute the cut-
ting circle.
Reversible cutters have cutting edges on opposite si-
des, so that when one edge becomes dull, the cutter may be ro-
tated in the head to allow the opposite cutting edge to be used.
In order to ensure that these cutting edges coincide at all
times with the cutting circle, it is known to locate the rever-
sible cutters in the shaping head positively ~ means of pinsor bolts. If the shaping head is incorporated into the manual
shaping machine, the cutting circle corresponds to the effec-
tive cutting area of the reversible cutters. If optimal cut-
ting performance is to be o~tained, the distance between the
outermost edge of the cuttin~ area and the fixed bearing sur-
face of the manual shaping machine must have a specific dimen-
sion. However, depending upon dimensional discrepancies bet-
ween individual parts o~ the manual shaping machine, this
distance may vary, and optimal cutting per~ormance o~ the manu-
al shaping machine is therefore not alwa~s assured.
It is therefore the purpose of the present inventionto provide a shaping head having reversible cutters and ensu~
rin~ optimal cutting conditions even in the event of large
dimensional discrepancies between individual parts of the
manual shaping machineO
According to the present invention, there is provided
a shaping head having interchangeable, reversible cutters, the
projecting outer cutting edges o~ which constitute the cutting
circle, characterized in that at least one adjustable stop-
element, secured to shaping head, is associated with eachreversible cutter, said cutter bearing against the stop-eLement
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for the purpose of adjustment to the cutting circle. The stop-
element comprises a stop-cone having an axis substantially
at right angles to the surface of the reversible cutter, ~aid
stop-cone being axially adjustable and bearing against the
inner cutting edge of the said cutter.
This adjustment ma~es it possible to obtain the desi-
red optimal distance between the outermost edge of the cutting
area and the fixed bearing surface, thus making it possible to
adjust each individual manual shaping machine for optimal
cutting performance. This is particularly advantageous in the
case of manual shaping machines the parts of which are made by
modern production methods, without any machining, or example
by injection-moulding. Although these modern methods greatly
reduce production costs, larger tolerances must inevitably be
allowed for. These tolerances may be compensated fox by the
adjustability of the reversible cutters according to the
invention.
According to one advantageous example of embodiment,
the stop-element is formed by the truncated-conical head of a
commercial countersunk screw bolt, against the outer surface
of which the cutting edge of the reversible cutter bears. A
suitable choice of the angle of the conical head of the counter-
sunk bolt, and of the bevel-angle of the cutting edge of the
cutter, ensures point contact between the stop cone and the
reversible cutter. This provides particularly accurate adjust-
ment of the cutter.
Another advantageous characteristic of the shaping
head according to the invention resides in the easily proces-
sed ~machined) bearing surface of a shaft-body against which
the reversible cutters are pressed by means of jaws (straps~.
According to the invention, these jaws have holes in alignment
with the stop elements, through which the said stop element
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may be adjusted with an appropriate tool. Moreover 3 this
adjustment may be carried out with the shaping installed or
removed.
The jaws are secured to the shaft-body in known
fashion by means of boltsO According to ~he invention, however,
these bolts are screwed into the steel shaft secured in the
aluminum shaft-body, thus ensuring a more reliable joint.
According to the invention, the jaw is also provided
with a clamping surface for the reversible blade, and with an
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opposing supporting surface. Now if the jaw is secured im
improperly to the shaft body, i.e. with the supporting surface,
instead of the clamping surface, towards the reversible blade,
then the supporting surface rests upon the head of the stop-
element and the reversible cutter cannot be clamped. The
operator is therefore immediately aware that the jaw is im-
properly fitted and may take appropriate action to correct the
matter.
An example of embodiment of the invention is explained
hereinafter in conjunction with the drawing attached hereto,
wherein :
Fig.l is a side elevation of ~he shaping head, in part
section along the lines I-I and II~II in Fig.2 ;
Fig. 2 is a front elevation of the shaping head;
Fig. 3 is a detail from Fig. 1, to an enlarged scale~
Shaping head 1 illustrated in Fig. 1 and 2 has a
carrier in the form of shaft~body 2 made of aluminum into which
a steel shaft 3 is pressed. Shaft body 2 is defined by two
parallel bearing surfaces 4, interrupted centrally by a wide
recess 5 and outwardly by a narrower recess 6. Radial thread-
ed holes 7, for attachment bolts 8, pass through shaft body
2 and shaft 3.
Bolts 8 are used to secure jaws ~plates) 9 to shaft-
body 2, the said jaws having a supporting surface 10 of width
B on one side and a clamping surface 11 on the other side.
Through-passages 12, with counterbores 13, are located in the
jaws in the vicinity of clamping surfaces llo
Diagonally opposite, two reversible cutters 14 are
pressed, by clamping surfaces 11 of jaws 9, against bearing
surfaces 4. Cutters 14 have cutting edges 15 on both sides,
the outer edges being the generatrix of cutting circle 16.
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Jaws 9 carry safety re-taining-dowels 17 which engage
in apertures in cutters 14 and prevent improperly clamped
cutters from flying off.
Arranged in shaft body 2, parallel with threaded holes
7, are additional threaded holes 19 into which stop-elements
20 are screwed. In the example of embodiment illustrated,
these elemen~s are commercial countersunk screws, the heads
of which serve as stop-cones 21 having a cone-angle 22. (see
Fig. 3). Inner cutting edge 15 of cutter 14 rests upon stop-
cone 21. Cone-angle 22 of stop-cone 21, and bevel-angle 23
of cutting edge 15 are matched in such a manner that only the
outer tip of the cutting edge is in contact~ with cone 21.
When reversible cutters 14 are to be accurately adjust-
ed, jaws 9 are first of all fitted loosely. Stop-element 20
i5 rotated, by means of a tool introduced through passage 12,
until outermost cutting edge 15 coincides with cutting circle
16. The said stop-element is then secured with a locking
adhesive, to prevent it from being inadvertently loosened.
The dis-tance between the outermost edge of jaw 9 and
the closest point on stop-cone 21 may be marked A. If the
width s of supporting surface 10 of jaw 9 is made greater than
distance A, then if jaw 9 is improperly fitted, cutter 14 can-
not be clamped in position, since supporting surface 10 will
be seated upon end-face 24 of stop cone 21.
