Machine tools abstract
A tool head for use in machine tools includes a base body, a tool
shank adapted to be coupled to a machine spindle and protruding
axially over the base body, at least one working slide adapted to
be displaced essentially transversely with respect to a base body
axis, and an adjusting motor disposed in the base body and acting
upon the working slide in the direction of displacement by a transmission.
In order to attain a compact, easily assembled, and safely operating
construction, the transmission includes an output shaft aligned
coaxially with respect to the axis of the base body and carrying
a drive sprocket which meshes with a tooth rack on the side of the
working slide. The adjusting motor also includes a driven shaft
aligned with the output shaft on the transmission side. To ease
assembly, the tool head is constructed of three assemblies adapted
to be removably connected to each other at axial separation locations,
a slide assembly which includes the working slide, a drive assembly
which includes the adjusting motor and the transmission, and a connecting
assembly which includes the tool shank and the power supply device.
Machine tools claims
What is claimed is:
1. A tool head for use in machine tools, comprising a base body,
a tool shank adapted to be coupled to a machine spindle and protruding
axially over the base body, at least one working slide adapted to
be displaced essentially transversely with respect to a base body
axis and having a tool holding fixture protruding over a front face
thereof, an adjusting motor disposed in the base body and acting
on the working slide in a direction of displacement by means of
a transmission means, wherein the transmission means comprises an
output shaft adapted to be rotated concentrically with respect to
the base body axis, the output shaft carrying a drive sprocket disposed
on a free end of the output shaft, the drive sprocket meshing with
a first tooth rack disposed on a side of the working slide, and
connected to the working slide, and a compensation slide disposed
in the base body, the compensation slide adapted to be displaced
in a direction opposed to the working slide by a second tooth rack
that meshes with the drive sprocket and which is disposed on a side
of the compensation slide and connected thereto, wherein the working
slide and the compensation slide are disposed at an axial distance
from one another under formation of a free space, and the first
tooth rack of the working slide, the second tooth rack of the compensation
slide and the drive sprocket extend into the free space, and wherein
the compensation slide includes an elongated hole as a through passage
for the output shaft.
2. The tool head of claim 1 wherein the working slide is guided
in a linear guide fixed to the base body.
3. The tool head of claim 1 wherein at least part of the compensation
slide comprises a heavy metal.
4. The tool head of claim 1 wherein the working slide and a slide
leg formed thereon carry the second tooth rack and have an essentially
L-shaped profile.
5. The tool head of claim 4 wherein the compensation slide and
a compensation leg formed thereon carry the second tooth rack and
have an essentially L-shaped profile.
6. The tool head of claim 5 wherein the slide leg of the working
slide and the compensation leg of the compensation slide which carry
the tooth racks are aligned in parallel to one another and are disposed
at opposing sides of the drive sprocket.
7. The tool head of claim 1 wherein the working slide includes
at least one hollow space.
8. The tool head of claim 1 wherein the at least one hollow space
is spaced with respect to the tool coupling fixture in the direction
of displacement and filled with a heavy metal.
9. The tool head of claim 1 wherein the compensation slide carries
a removable or exchangeable mass element.
10. The tool head of claim 1 wherein the transmission means comprises
a reducing gear mechanism having input and output axes which are
aligned with each other, wherein the reducing gear mechanism is
formed as a harmonic drive transmission or a planetary transmission.
11. The tool head of claim 10 wherein the adjusting motor and
the reducing gear mechanism are disposed to radially and axially
interpenetrate each other.
12. The tool head of claim 11 wherein the adjusting motor or a
driven shaft thereof includes a central opening for accepting the
reducing gear mechanism.
13. The tool head of claim 11 wherein the reducing gear mechanism
includes a central opening for accepting the adjusting motor.
14. The tool head of claim 1 wherein the working slide is guided
in a prismatic anti-friction guide fixed in the base body and free
from play, the anti-friction guide being elastically deformable.
15. The tool head of claim 1 wherein the compensation slide is
guided in an anti-friction guide fixed in the base body.
16. The tool head of claim 1 including a slide assembly for accepting
the working slide and the compensation slide, a drive assembly for
accepting the adjusting motor and the transmission means, and a
connecting assembly comprising the tool shank, the slide assembly
and connecting assembly being removably connected to the drive assembly
at axial locations on opposing sides of the drive assembly.
17. The tool head of claim 16 wherein the slide assembly comprises
a measuring device adapted to directly measure displacement of the
working slide with respect to the base body.
18. The tool head of claim 17 wherein at least one of the slide
assembly and the drive assembly comprise measuring and control electronics
connected to the measuring device and controlling the adjusting
motor.
19. The tool head of claim 16 wherein the connecting assembly
includes an interface for an inductive power supply and data transmission.
20. The tool head of claim 19 wherein the power supply interface
is disposed in a housing, an outer side of the housing being adapted
to receive a coolant by way of a gap space.
21. The tool head of claim 16 wherein the drive assembly extends
into an axially open recess of the slide assembly with an axially
protruding bearing sleeve for the output shaft.
22. The tool head of claim 21 wherein the bearing sleeve extends
into the elongated hole of the compensation slide.
23. The tool head of claim 16 wherein the slide assembly comprises
a jacket tube braced to the base body by a cover part to prevent
rotation or displacement of the jacket tube.
24. The tool head of claim 16 wherein the base body comprises
an interface for a galvanic power supply and data transmission,
said interface being located in the region of the slide assembly.
25. The tool head of claim 1 wherein a gap space is located in
a region of a recess in the base body on an outer side of a motor
housing of the adjusting motor, the gap space adapted to receive
a coolant for cooling the adjusting motor.
26. The tool head of claim 25 wherein a part of the recess containing
the gap space is disposed in the connecting assembly.
27. The tool head of claim 1 wherein the first tooth rack connected
to the working slide is divided into two axially separated toothed
parts adapted to be displaced or rotated with respect to each other
and adapted to be rigidly coupled to each other.
28. The tool head of claim 1 wherein the working slide includes
a radial bore for connection to a coolant conduit in the base body,
the bore communicating with the tool holding fixture and aligned
parallel to the direction of displacement.
29. The tool head of claim 28 wherein the coolant conduit in the
base body comprises a pipe which slidably and sealingly engages
the radial bore.
30. A tool head for use in machine tools, comprising a base body,
a tool shank adapted to be coupled to a machine spindle and protruding
axially over the base body, at least one working slide adapted to
be displaced essentially transversely with respect to a base body
axis and having a tool holding fixture protruding over a front face
thereof, and an adjusting motor disposed in the base body and acting
on the working slide in a direction of displacement by means of
a transmission means, wherein the transmission means comprises an
output shaft adapted to be rotated concentrically with respect to
the base body axis, the output shaft carrying a drive sprocket which
meshes with toothing on a side of the working slide, wherein the
toothing on the side of the working slide is disposed on an intermediate
transmission element which is linearly guided in the base body,
the intermediate transmission element being coupled to the working
slide by a wedge gear or an intermediate gearwheel.
31. The tool head of claim 30 wherein the wedge gear is formed
by complementary, meshing slanted toothings disposed at the intermediate
transmission element and at the working slide.
32. The tool head of claim 30 wherein a compensation slide is
disposed in the base body and adapted to be displaced oppositely
with respect to the working slide by a tooth rack which meshes with
the drive sprocket and is disposed at the side of the compensation
slide and fixed thereto.
33. A tool head for use in machine tools, comprising a base body,
a tool shank adapted to be coupled to a machine spindle and protruding
axially over the base body, at least one working slide adapted to
be displaced essentially transversely with respect to a base body
axis and having a tool holding fixture protruding over a front face
thereof, an adjusting motor disposed in the base body and acting
on the working slide in a direction of displacement by means of
a transmission means, wherein the transmission means comprises an
output shaft adapted to be rotated concentrically with respect to
the base body axis, the output shaft carrying a drive sprocket which
meshes with a tooth rack disposed on a side of the working slide
and connected to the working slide, wherein the working slide is
formed as a round slide adapted to be rotated about an axis parallel
to the base body axis, and the tooth rack is part of a gearwheel
which meshes with the drive sprocket.
34. A tool head for use in machine tools, comprising a base body,
a tool shank adapted to be coupled to a machine spindle and protruding
axially
over the base body, at least one working slide adapted to be displaced
essentially transversely with respect to a base body axis and having
a tool holding fixture protruding over a front face thereof, an
adjusting motor disposed in the base body and acting on the working
slide in a direction of displacement by means of a transmission
means, wherein the transmission means comprises an output shaft
adapted to be rotated concentrically with respect to the base body
axis, the output shaft carrying a drive sprocket which meshes with
a tooth rack disposed on a side of the working slide an connected
to the working slide, and wherein the transmission means comprises
a reducing gear mechanism having input and output axes which are
aligned with each other, wherein the reducing gear mechanism is
formed as a harmonic drive transmission or a planetary transmission.
35. A tool head for use in machine tools, comprising a base body,
a tool shank adapted to be coupled to a machine spindle and protruding
axially over the base body, at least one working slide adapted to
be displaced essentially transversely with respect to a base body
axis and having a tool holding fixture protruding over a front face
thereof, an adjusting motor disposed in the base body and acting
on the working slide in a direction of displacement by means of
a transmission means, wherein the transmission means comprises an
output shaft adapted to be rotated concentrically with respect to
the base body axis, the output shaft carrying a drive sprocket which
meshes with a tooth rack disposed on a side of the working slide
and connected to the working slide, wherein the working slide is
guided in a prismatic anti-friction guide fixed in the base body
and free from play, the anti-friction guide being elastically deformable
up to a limit of elastic deformability, and a slideway for the working
slide becoming active upon the anti-friction guide reaching the
limit of elastic deformability.
36. A tool head for use in machine tools, comprising a base body,
a tool shank adapted to be coupled to a machine spindle and protruding
axially over the base body, at least one working slide adapted to
be displaced essentially transversely with respect to a base body
axis and having a tool holding fixture protruding over a front face
thereof, and an adjusting motor disposed in the base body and acting
on the working slide in a direction of displacement by means of
a transmission means, the tool head including a slide assembly for
accepting the working slide, a drive assembly for accepting the
adjusting motor and the transmission means, and a connecting assembly
comprising the tool shank, the slide assembly and connecting assembly
being connected to the drive assembly at axial locations on opposing
sides of the drive assembly, wherein the slide assembly comprises
a measuring device adapted to directly measure displacement of the
working slide with respect to the base body, at least one of the
slide assembly and the drive assembly comprise measuring and control
electronics connected to the measuring device and controlling the
adjusting motor, and the connecting assembly comprises an interface
for an inductive power supply and data transmission.
37. A tool head for use in machine tools, comprising a base body,
a tool shank adapted to be coupled to a machine spindle and protruding
axially over the base body, at least one working slide adapted to
be displaced essentially transversely with respect to a base body
axis and having a tool holding fixture protruding over a front face
thereof, and an adjusting motor disposed in the base body and acting
on the working slide in a direction of displacement by means of
a transmission means, wherein the adjusting motor is disposed with
its rotationally symmetric motor housing in a recess of the base
body, the recess being concentric with respect to the base body
axis, leaving free a gap space receiving a coolant for cooling the
motor.
Machine tools description
FIELD OF THE INVENTION
The invention is related to a tool head for use in machine tools,
comprising a base body, a tool shank which is adapted to be coupled
to a machine spindle and which protrudes axially over the base body,
at least one working slide which is adapted to be displaced essentially
transversely with respect to a base body axis and which has a tool
holding fixture which protrudes over a front face thereof, and an
electrical adjusting motor which is disposed in the base body and
which acts upon the working slide in the direction of displacement
by means of transmission means.
BACKGROUND OF THE INVENTION
A tool head of this type is known (DE-A-4330822), in which the
adjusting motor with its essentially cylindrical motor housing is
disposed in a transverse recess of the base body, which recess is
aligned transversely with respect to the base body axis and intersects
the base body axis, the driven shaft of the motor being aligned
in parallel to the transverse recess. Transmission means are provided
for driving the working slide, which comprise a gearwheel which
is disposed on the driven shaft of the motor, a drive sprocket which
meshes with the gearwheel, and a threaded spindle rigidly connected
thereto. A sliding block having a slanted toothing is guided on
the threaded spindle, which slanted toothing meshes with a complementary
slanted toothing of a counterpart disposed on the slide. The transmission
means are in this instance disposed eccentrically in the base body.
An annular coil housing is disposed at the side of the tool shank,
in which there is located a secondary coil with corresponding stabilizing
electronics, which coil is part of an inductive transmission path
of a power supply device for the adjusting motor and the electronic
circuits which are located in the tool head. In principle, it is
possible to also use the induction path also for bidirectional data
transmission, wherein the data signals are modulated onto the induction
current. The
primary coil of the inductive transmission path is disposed in
a coil housing on the machine side, which extends radially outward
of the tool shank into the free space between the face of the machine
spindle and the face of the coil housing on the tool head side.
The centrifugal force-free arrangement of the adjusting motor and
the transmission has hitherto not been adequately solved. Furthermore,
the construction size and the assembly and servicing possibilities
of the known tool head are not satisfactory.
Based on this, the object of the invention is to develop a tool
head of the type described above, which makes an assembly and servicing
friendly yet compact construction possible and ensures a vibration-free
operation.
SUMMARY OF THE INVENTION
The solution according to the invention is based foremost on the
idea that the transmission means comprise an output shaft which
is adapted to be rotated concentrically with respect to the base
body axis, which output shaft carries a drive sprocket which meshes
with toothing on the side of the working slide. Advantageously,
the toothing on the side of the working slide is rigidly connected
to the working slide.
According to a further variant of the invention, it is provided
that the toothing on the side of the working slide is disposed on
an intermediate transmission element which is linearly guided in
the base body and which in turn is coupled to the working slide
by means of a wedge gear or an intermediate gearwheel. In this,
the wedge gear may be formed by complementary, meshing slanted toothings
which are disposed at the intermediate transmission element and
at the working slide. With this embodiment a self-locking effect
is attained and free play is avoided, which makes it possible to
cut the power to the adjusting motor during each driving pause or
to turn it off.
The working slide is advantageously guided in a linear guide, while
the toothing is formed by a tooth rack which meshes with the drive
sprocket. In order to compensate internal centrifugal forces, it
is of advantage when an additional compensation slide is provided,
which is disposed in the base body and which is adapted to be displaced
oppositely with respect to the working slide by means of a tooth
rack which meshes with the drive sprocket and which is disposed
at the side of the compensation slide. In order to reduce the size
of the construction, the compensation slide expediently consists
at least partially of a heavy metal. On the other hand the working
slide may to this end comprise at least one hollow space, wherein
it may be of advantage for the unilateral compensation of free play
in the region of the working slide, when at least one hollow space
which is located at a distance from the tool holding fixture in
the direction of displacement is filled with a heavy metal. Since
the mass distribution within the tool head can only be approximately
calculated beforehand, it is of advantage for attaining a precise
balance, when the compensation slide carries a removable or exchangeable
mass element, the mass of which is preferably adapted to be changed
by removal of material.
According to a modified embodiment of the invention the working
slide is formed to be a round slide which is adapted to be rotated
about an axis which is parallel to the base body axis and the toothing
is formed by a gearwheel which meshes with the drive sprocket. The
tool holding fixture is in this case disposed eccentrically on the
round slide. Since there is no mass displacement when the round
slide is rotated, there is no need for a compensation slide in this
arrangement.
According to a preferred embodiment of the invention the adjusting
motor has a driven shaft which is aligned with the output shaft
at the transmission side, and the transmission means are formed
to be a reducing gear mechanism having input and output axes which
are aligned to one another. This may be attained especially easily
when the reducing gear mechanism is formed to be a harmonic drive
transmission. In order to also attain an especially compact construction,
it is proposed according to a further advantageous embodiment of
the invention that the adjusting motor and the transmission means
are disposed such that they radially and axially interpenetrate
each other at least partially. This may be realized either in that
the adjusting motor or the drive shaft thereof comprises a central
opening for accepting the transmission means or that the transmission
means comprise a central opening for accepting the adjusting motor.
In order to achieve a high degree of positioning precision with
little friction, it is of advantage, that the working slide is guided
in a preferably prismatic anti-friction guide which is fixed in
the base body and which is free from play. The anti-friction guide
is subject to a stress and bending moment by the cutting forces
acting thereon in spite of a pretension. It is of advantage, for
the anti-friction guide to be elastically deformable and for a slideway
for the working slide to become active upon reaching the limit of
elastic deformability. By this an improvement of the damping behavior
is attained even when high momentary loads occur. Furthermore, it
is ensured that no permanent deformations are formed on the guide
rollers and the slide.
In principle it is possible to also guide the compensation slide
in an anti-friction guide which is fixed in the base body.
In order to increase the adjusting precision, it is of advantage,
to fashion the interaction of the working slide and the drive sprocket
such that it is without free play. In order to attain this, it is
proposed according to the invention that the tooth rack which is
fixed to the working slide or the drive sprocket is divided into
two axially separated toothed parts which are adapted to be displaced
or rotated with respect to each other and which are adapted to be
rigidly coupled to each other.
In the case of the working slide which is adapted to be displaced
along a linear guide, it has proven to be especially advantageous
for constructional and energetic reasons, when the working slide
and a leg which is formed thereon and which carries the corresponding
tooth rack have an essentially L-shaped profile, and when also the
compensation slide and a leg which is formed thereon and which carries
the corresponding tooth rack have an essentially L-shaped profile.
The profile legs of the working slide and of the compensation slide
which carry the tooth racks are expediently aligned in parallel
to one another and are disposed at opposing sides of the drive sprocket.
In order to attain a high degree of assembling and servicing ease,
it is proposed according to an alternative or preferred embodiment
of the invention that the base body is divided into a slide assembly
for accepting the working slide and possibly the compensation slide,
a drive assembly for accepting the adjusting motor and the transmission
means, and a connecting assembly comprising the tool shank, which
are removably connected to each other at axial separation locations.
In this, the slide assembly expediently comprises a measuring device
which is adapted to directly measure the displacement of the working
slide with respect to the base body. Further, the slide assembly
and/or the drive assembly comprise measuring and control electronics
which are connected to the measuring device and serve to control
the adjusting motor. The connecting assembly comprise an interface
for an inductive power supply or data transmission, while the base
body may comprises an interface for a galvanic power supply and
data transmission, which interface is preferably located in the
region of the slide assembly.
A preferred embodiment of the invention provides that the working
slide and the compensation slide are disposed at an axial distance
from one another under formation of a free space, and that the tooth
racks of the working slide and the compensation slide, as well as
the drive sprocket which is disposed on the free end of the output
shaft, extend into the free space. In order to make this possible
the compensation slide expediently comprises an elongated hole for
the through passage of the output shaft. In order to be able to
transmit the forces acting on the drive sprocket to the base body
without any loss of adjusting precision, it is of advantage, that
the drive assembly extends into an axially open recess of the slide
assembly with an axially protruding bearing sleeve for the output
shaft. In this, the bearing sleeve expediently extends through the
elongated hole of the compensation slide.
A further preferred or alternative embodiment of the invention
provides that the adjusting motor engages with a rotationally symmetric
motor housing a recess of the base body, which recess is concentric
with respect to the base body axis and which may comprise a gap
space which is delimited by the motor housing, which is fluid tight,
and which is adapted to be subjected to a coolant for cooling the
motor. That part of the recess which comprises the gap space is
expediently located in the connecting assembly. Since thermal energy
must also be dissipated from the region of the interface for the
power supply and data transmission, it is of advantage that the
power supply and data transmission interface are disposed in a housing
part of the connecting assembly, the outer side of which is adapted
to be subjected over a broad surface area to a coolant flow.
In order to supply the tool holding fixture with a coolant and
lubricant, the working slide may have a radial bore for the connection
to a coolant conduit in the base body, which bore communicates with
the tool holding fixture and is aligned parallel to the direction
of displacement. To this end, the coolant conduit in the base body
comprises a pipe which slidably and sealingly engages the radial
bore.
In order to protect the slide assembly from dirt and the coolant
and lubricant, it comprises a jacket tube which is braced to the
base body by means of a cover part, such that it cannot be rotated
or displaced.
The tool head according to the invention is advantageously used
as a facing head or bore head.
BRIEF DESCRIPTION OF THE DRAWINGS
In the following the invention will be described in greater detail
with reference to an embodiment schematically shown in the drawing,
in which:
FIG. 1 shows a side view of a tool head designed to be a facing
head;
FIG. 2 shows a plan view of the tool head according to FIG. 1;
FIG. 3 shows a section along the line III--III in FIG. 2;
FIG. 4 shows a section along the line IV--IV in FIG. 2;
FIG. 5 shows a section along the line V--V in FIG. 4;
FIG. 6 shows a plan view of the driving assembly of the tool head
with the slide assembly being removed;
FIG. 7 shows a plan view of a facing head modified with respect
to FIGS. 1 to 6 the working slide of which is designed to be a
round slide; and
FIG. 8 shows a plan view of a modified embodiment of a facing head
having an intermediate transmission element which is disposed between
the drive sprocket and the working slide and which is formed to
be a wedge gear mechanism.
DETAILED DESCRIPTION OF THE INVENTION
The tool head shown in the drawing is intended to be used as a
facing head in machine tools. The tool head essentially consists
of a base body 10 which is adapted to be rotated about an axis of
rotation 12 a working slide 16 which is adapted to be displaced
within the base body 10 transversely with respect to the axis 12
and which carries a tool holding fixture 14 for a cutting tool,
a compensation slide 18 (only FIGS. 1 to 6) which is adapted to
be displaced within the base body 10 in a direction opposite to
that of the working slide 16 a measuring device 20 for directly
measuring the displacement path of the working slide 16 with respect
to the base body 10 an electric adjusting motor 24 which acts on
the working slide 16 and the compensation slide 18 by way of an
interposed reducing gear mechanism 22 a power supply device 26
and a tool shank 28 which protrudes axially over the base body 10
and which is adapted to be coupled to a machine spindle (not shown)
of a machine tool.
The tool head is constructed of three assemblies which are adapted
to be removably coupled to each other at axial separation locations
30 32 a slide assembly 34 which contains the working slide 16
and the compensation slide 18 a drive assembly 36 which contains
the adjusting motor 24 and the reducing gear mechanism 22 and a
connecting assembly 38 which contains the tool shank 28 and the
power supply device 26. The slide assembly 34 is surrounded at its
circumference by a jacket 40 made of metal or plastic and is closed
off at its face side by a cover part 42. The joining of the slide
assembly 34 and the drive assembly 36 is achieved by means of axially
parallel bolts 44 which are screwed into threaded bores 46 of the
drive assembly 36 and pass through the cover part 42 and openings
(not shown) in the slide assembly 34. The connecting assembly 38
is bolted to the drive assembly 36 from the opposing face side by
means of bolts 48.
The working slide 16 which extends with the tool holding fixture
14 through an elongated hole 50 in the cover part 42 is guided in
the direction of displacement in a prismatic anti-friction guide
52 which is fixed in the base body 10. The anti-friction guide is
made free from play by means of clamping wedges (not shown) which
press against the guide prisms 54 which are fixed to the base body.
Since the anti-friction guide 52 is subjected to a moment load through
the tool holding fixture 14 upon the occurrence of high cutting
forces, which may lead to a deformation, a slideway 56 for the working
slide 16 which becomes active upon reaching the limit of elastic
deformability is additionally provided. In the unstressed state
a free space 58 is formed in front of the slideway 56 into which
the guide prism 54 which is fixed to the working slide 16 may elastically
bend under stress, until it comes into contact with the slideway
56. The slideway ensures that the tool is dampened during heavy
cutting and that chattering or vibrations are thus avoided. The
working slide 16 is provided with hollow spaces 17 at one of its
broad sides. FIG. 3 shows that the hollow space which is located
furthest from the tool holding fixture as seen in the direction
of displacement is filled with a heavy metal 19.
The compensation slide 18 which preferably is made of a heavy metal
is also guided in an anti-friction guide 60 which is fixed in the
base body and which does not have to be free from play. On its one
broad side the compensation slide 18 is fitted with a removable
or exchangeable plate-shaped mass element 21 the mass of which
can be adjusted by removal of material.
The working slide 16 and the compensation slide 18 are disposed
at an axial distance from one another. As can be seen especially
in FIG. 4 they have an essentially L-shaped profile, wherein tooth
racks 68 70 are disposed on the short legs 67 69 which extend
into the region of the spacing 66 which tooth racks mesh with a
drive sprocket 74 which is disposed on the output shaft 72 of the
reducing gear mechanism 22 which is coaxial with respect to the
axis of rotation 12. In this manner the working slide 16 and the
compensation slide 18 are displaced in opposite directions upon
rotation of the drive sprocket 74.
The output shaft 72 is borne in a bearing sleeve 76 which axially
protrudes over the drive assembly 36 by means of two roller bearings
77. It extends together with the bearing sleeve 76 through an opening
78 in the slide assembly 34 and through an elongated hole 80 in
the compensation slide 18 from the side of the drive assembly 36.
The reducing gear mechanism 22 is a harmonic drive transmission,
the oval drive plate 82 of which is coupled to the driven shaft
84 of the adjusting motor 24 which is coaxial with respect to the
axis of rotation 12 the internally toothed ring 86 of which is
connected to the base body 10 in the region of the drive assembly
36 by means of bolts 88 such that it cannot be rotated, and the
externally toothed flexible sleeve 90 of which is coupled to the
output shaft 72 by means of the coupling part 92.
The adjusting motor 24 which is schematically shown in FIGS. 3
and 4 and which is fitted with an encoder 94 axially protrudes over
the drive assembly 36 with its motor housing 95 and extends there
into a cylindrical recess 96 in the connecting assembly 38 which
recess is concentric with respect to the axis of rotation 12 leaving
free a gap space 98. The gap space 98 communicates with the conduits
100 102 of the connecting assembly 38 and can be subjected through
these with a coolant by way of the machine tool. In this manner
the heat generated during the operation of the adjusting motor may
be dissipated.
The power supply device 26 comprises a coil housing 104 which is
disposed on the connecting assembly 38 in which a secondary coil
with corresponding stabilizing electronics which is embedded in
a mechanically tough casting material consisting of resin or synthetic
material is disposed.
The secondary coil is part of an inductive transmission path of
the power supply device 26 which serves to supply current to the
adjusting motor 24 and the electronic circuits 106 in the tool head.
The inductive path further serves a bidirectional data transmission,
wherein the data signals are modulated onto the induction current.
The primary coil (not shown) of the power supply device 26 is disposed
in a coil housing on the machine side, which extends radially outward
from the tool shank 28 into a free gap between the face of a machine
spindle and the face of the coil housing 104 on the tool head side
on the outside of the coil housing 104 there is a gap space 108
which communicates by way of conduits 109 with the gap space 98
on the motor side and can thus be subjected to a coolant. In this
manner the heat generated by the secondary coil of the power supply
device 26 may be dissipated.
A fraction of the coolant and lubricant supplied through the conduits
100 102 is led within the base body 10 to the tool holding fixture
14 and from there to a cutting tool carrier (not shown). To this
end the working slide 14 comprises a radial bore 110 which is aligned
in parallel to the direction of its displacement and extends up
to the tool holding fixture 14 into which radial bore a pipe which
communicates with the coolant conduits 112 of the base body 10 extends
in a sliding and sealing manner.
An interface having a plug socket 116 for the galvanic power supply
and data transmission is additionally disposed in the region of
the slide assembly.
The embodiment of a facing head as shown in plan view in FIG. 7
differs from the embodiment of FIGS. 1 to 6 in that the working
slide 16 is designed to be a round slide which is eccentrically
disposed on the tool head and which is adapted to be rotated by
means of the drive sprocket 74 and a gearwheel 68' which is rigidly
connected to the working slide, thereby effecting an essentially
radial displacement of the tool holding fixture 14. The rotation
of the round slide 16 causes no mass displacement, so that a compensation
slide is not necessary in this instance. Due to this a significantly
lower power rating of the adjusting motor 24 is sufficient.
The embodiment of a facing head as shown in plan view in FIG. 8
differs from the embodiment of FIGS. 1 to 6 in that an intermediate
transmission element 120 is disposed between the drive sprocket
74 and the working slide 16 which is formed to be a linear slide,
which element is linearly guided in the tool head in the directions
of the double arrow 122 and which comprises a linear toothing 124
which meshes with the sprocket 74 as well as a slanted toothing
126' which is oriented toward the working slide 16 and which cooperates
with a complementary slanted toothing 126" in the sense of
a wedge transmission, so that the working slide is displaced in
the direction of the double arrow 128 thereby radially displacing
the tool holding fixture 14. The slanted toothing 126', 126"
leads to an additional reduction of the displacement path of the
working slide 16 and to a self-locking effect in any intermediate
position. The slanted toothing 126', 126" may also be freed
from play with simple means.
In summary the following is to be stated: The invention is related
to a tool head for use in machine tools. The tool head comprises
a base body 10 a tool shank 28 which is adapted to be coupled to
a machine spindle and which protrudes axially over the base body
10 at least one working slide 16 which is adapted to be displaced
essentially transversely with respect to a base body axis 12 and
an adjusting motor 24 which is disposed in the base body and which
acts upon the working slide 16 in the direction of displacement
by means of transmission means 22 72 74 68. In order to attain
a compact, easily assembled, and safely operating construction,
it is proposed according to the invention that the transmission
means comprise an output shaft 72 which is aligned coaxially with
respect to the axis of the base body, which output shaft carries
a drive sprocket 74 which meshes with a tooth rack 68 124 on the
side of the working slide. A further improvement in this respect
is attained when the adjusting motor 24 comprises a driven shaft
84 which is aligned with the output shaft 72 on the transmission
side. In order to improve the ease of assembly, the tool head is
constructed of three assemblies which are adapted to be removably
connected to each other at axial separation locations 30 32 a
slide assembly which contains the working slide 16 a drive asembly
36 which contains the adjusting motor and the transmission means,
and a connecting assembly 38 which contains the tool shank 28 and
the power supply device 26. |