[0001] The invention refers to an accessory tool for grinding machines which, according
to three different pre-settings, enables to sharpen helical steel and metal points,
to carry out boring as well as threading operations. The tool performs the support
of the parts being treated in centered longitudinal position. This permits the centering
effect operations which carry out a greater penetration, a lower effort with low limits
of tolerance, and it allows to change the position of the part being treated by rotation.
[0002] For sharpening points, grinding machines are at present used with circu lar motion
and intermittent progression by means of cams.
[0003] For the boring operations, at present a different machine is required, and for threading
too. It has to be born in mind, on the other hand, that this device operating with
intermittent progression, carry out threading operations but on the entrance of the
cutting parts, and they are ineffi cient in cavity operations.
[0004] The invention permits to carry out the above three operations by means of only one
accessory tool which can be set on the plane of the grinding machine and it can be
set each time by adding or taking away organs according to the operation to carry
out. Therefore, only one grinding machine can be used.
[0005] The tool employs on a table a base holding a cylindrical coaxial part of axial turning
piece to set on ball bearing and with a conical stabi lizer of integral axial support
of pivot operating on the top, as a surface delimitator on the point to sharpen of
the part held on hanging support. From the back position of rest, the delimitator
can be brought on the top. After having performed sharpening on one of its sides,
the protection is changed for the subsequent phase by turning the delimitator and
by fixing it in position by means of a pin. On the inside head of the setter, a turning
ring can be fitted which on the arm holds the support of the part to be treated by
means of a handle. Iron the upper rest position, the support is brought by hand into
working position. By means of a small mirror, the alignment of the exposure point
wall can be observed on the surface limitator. With an insertion pin foreseen longitudinally
on the setter body, the ring and, therefore, the point bearing spindle can be fixed
in the two positions.
[0006] For the boring operation, the ring is removed as well as the surface delimitator
with the relevant support, and a conical part is fitted into the setter which axially
holds a projecting pointed pin; on this one, by means of a fixing flange, a supporting
tool with adjustable slope is fitted for the right position of the part to be bored.
At the beginning, the support consists of the said coaxially gripping flange, which
on the lower side bears a longitudinal bar having a mobile bracket on the other end
with an upper dead centre aligned with the first one.
[0007] To preset the tool for the threading operation, a special supporting pin foreseen
for this purpose is fitted in the setter; the said support ing pin is equipped with
gripping parts which axially block the part to treat in the right position by introduction.
[0008] A form of execution is shown in the drawings of Table3 1 and 2; Fig. 1 is the perspective
view of the tool preset for the sharpening operation. Fig. 2 is the longitudinal section
of the presetter only to point out the conical stabilizer holding the face delimitating
pivot and, on the upper side, the fixing pin of the presetter ring. Fig. 3 is the
partial longitudinal section of the support with the point to sharpen inserted into
it. Fig. 4 is the view of the presetter with fitted threading tool and insert ed part
to treat. Fig. 5 is the transversal view of the previous picture complex in correspondence
with the gripping part of the supporting tool. Fig. 6 is the section of the presetter
prepared for a threading operation.
[0009] The version foresees the base 2, on table l, which supports the cylindrical setter
3 with ball bearings 4 for the rotation of part 5. In this one, pin 6 can be set in
a sliding way to surface end delimitator 7. The said pin passes through the conical
stabilizer 8 and can rotate with it. Outside the guide collar 9 is foreseen which
holds the rubber bellow 10 fit for preventing the dust entrance. At the head, knob
11 with pivot 12 is initially foreseen which acts as a guide by means of its gliding
on the lower bar 13. At the end 14 of bar 13, pin 12 can be positioned in rest condition.
Above, in a longitudinal cylindrical seat, pin 16 with knob 15 can slide on advance
spring 17 to allow the input of pin 16 into one of the notches 18 and 19 on the ring,
in order to change the incidence angle. The moving part consists of ring 20 holding
support 20 on arm 21. The operation point 24 can be set in support 22 with axial introduction
and blocking in spindle 23; the said point 24 is introduced into. bearing 25 supporting
spindle, rotating in 22. By means of knob 26 with pivot 27, the whole is blocked in
position after having checked by means of mirror 29 the horizontal position of the
cutter. When the alignment has been reached, bearing 25 is subsequently brought in
rotation by 180° Since tilting has thus been reached, the subsequent operating positions
are then obtained according to mnemonic checking sequences. The shim ad justment of
bearing 28 is given by support 22 and ring-like part 30. In order to fix the point
in sebsequent positions, the lifting lever device 31 is foreseen which, by means of
tooth 32 with return spring 33, is introduced into the counterposed pair of hollows
311 on pivot 35. The point positioning can become easier by means of cylindrical support
36 for points fitted with a conical setting part 37. In order to preset for threading
operations, ring 20 is taken away and the supporting pin 38 is inserted into the pre-setter;
by means of pinching part 39, part 40 to treat is blocked. For boring operations,
part 42 support ing dead-centre 43 is inserted into the conical hollow 41 of the setter
rotating part. On this one, the supporting tool is fitted for inserting its flange
44. In the lower side of the tool, bar 45 is foreseen on which the mobile bracket
46 can be fixed, fitted with dead centre 47 for supporting the operation part 48 between
it and part 43.
[0010] By changing the inclination, the incidence angle of the tool can be changed.
1) Tool for sharpening points, borers and threading parts, characteriz ed by the fact
that employs on a table a base holding a cylindrical coaxial part of axial turning
piece to set on ball bearing and with a conical stabilizer of integral axial support
of pivot operating on the top, as a surface delilitator on the point to sharpen of
the part held on hanging support. From the back position of rest, the delimitator
can be brought on the top. After having performed sharpening on one of its sides,
the protection is changed for the subsequent phase by turning the delimitator and
by fixing it in position by means of a pin. On the inside head of the setter, a turning
ring can be fitted which on the arm holds the support of the part to be treated by
means of a hand le. From the upper rest position, the support is brought by hand into
working position. By means of a small mirror, the alignment of the exposure point
wall can be observed on the surface limitator. With an insertion pin foreseen longitudinally
on the setter body, the ring and, therefore, the point bearing spindle can be fixed
in the two position.
2) Tool for sharpening points, borers and threading parts, according to the claim
1, characterized by the fact that for the boring operation, the ring is removed as
well as the surface delimitator with the relevant support, and a conical part is fitted
into the setter which axially holds a projecting pointed pin; on this one, by means
of a fixing flange, a supporting tool with adjustable slope is fitted for the right
position of the part to be bored. At the beginning, the support consists of the said
coaxially griPE ing flange, which on the lower side bears a longitudinal bar having a mobile bracket
on the other end with an upper dead centre aligned with the first one.
3) Tool for sharpening points, borers and threading parts, accord ing to the claim
1, characterized by the fact that to preset the tool for the threading operation,
a special supporting pin foreseen for this purpose is fitted in the setter; the said
supporting pin is equipped with gripping parts which axially block the part to treat
in the right position by introduction.
