Machine tools abstract
A tool head for use in machine tools comprising a base body coupled
to a machine spindle, comprising at least one tool-receiving means
for a cutting tool, and comprising a rotatable slide mechanism,
which eccentrically carries the tool-receiving means, and is rotated
about an eccentric axis parallel to the base-body axis with respect
to the base body in order to facilitate an adjusting of the cutting
radius of the cutting tool. A second rotatable slide mechanism is
provided which carries a second eccentric tool-receiving means,
and is rotated about a second eccentric axis parallel to the base-body
axis with respect to the base body in order to facilitate an adjusting
of the cutting radius of the respective cutting tool. Furthermore,
transmission means is arranged in the base body to facilitate a
simultaneous driving of the two rotatable slide mechanisms.
Machine tools claims
What is claimed is:
1. A tool head for use in machine tools comprising a base body
configured for connection to a machine spindle, comprising at least
one tool-receiving means for a cutting tool, and comprising a rotatable
slide mechanism for eccentrically carrying the tool-receiving means
and is rotatable about an eccentric axis which is parallel to the
base-body axis and with respect to the base body in order to facilitate
an adjusting of the cutting radius of the cutting tool, wherein
a second rotatable slide mechanism carries a second eccentric tool-receiving
means, and is rotatable about a second eccentric axis which is parallel
to the base-body axis and with respect to the base body in order
to facilitate an adjusting of the cutting radius of the respective
cutting tool.
2. The tool head according to claim 1 wherein transmission means
are arranged in the base body, which transmission means are coupled
to both rotatable slide mechanisms.
3. The tool head according to claim 1 wherein transmission means
are arranged in the base body, through which transmission means
the two rotatable slide mechanisms are simultaneously driven.
4. The tool head according to claim 3 wherein the transmission
means are coupled to an additional machine spindle and are configured
to be driven by a machine-located drive motor.
5. The tool head according to claim 3 wherein the transmission
means is driven by a drive motor integrated into the base body.
6. The tool head according to claim 5 wherein the drive motor
is one of a stepping motor and a servomotor.
7. The tool head according to claim 4 wherein the drive motor
is one of a stepping motor and a servomotor.
8. The tool head according to claim 2 wherein the transmission
means have a speed-reduction gearing in the form of one of a harmonic-drive
and planetary transmission.
9. The tool head according to claim 1 wherein the tool-receiving
means of the two rotatable slide mechanisms are diametrically opposite
one another with reference to the base-body axis.
10. The tool head according to claim 2 wherein the tool-receiving
means of the two rotatable slide mechanisms are adjusted radially
oppositely directed through the common transmission means.
11. The tool head according to claim 1 wherein the base body has
a centrally-oriented through opening, and wherein the transmission
means form a hollow-shaft unit enclosing the through opening.
12. The tool head according to claim 1 wherein the rotatable slide
mechanisms each have an eccentric disk supported for movement about
parallel axes, said eccentric disks being axially adjacent to one
another, and have axially extending and parallel crank arms which
carry the respective tool-receiving means oriented at a front-facing
side of the base body.
13. The tool head according to claim 12 wherein the outermost
eccentric disk adjacent to the front-facing side of the base body
has an opening for passage of the crank arm on the innermost eccentric
disk.
14. The tool head according to claim 12 wherein the front-facing
side openings of the base body are configured as elongate and curved
holes.
15. The tool head according to claim 14 wherein the tool-receiving
means carry on the outside shields to cover the elongate and curved
holes.
16. The tool head according to claim 13 wherein the opening in
the outermost eccentric disk is configured as an elongate hole.
17. The tool head according to claim 12 wherein the transmission
means are coupled through a common disk clutch concentrically supported
in the base body to the eccentric disks of the rotatable slide mechanisms.
18. The tool head according to claim 17 wherein the eccentric
disks and the disk clutch are arranged sandwichlike axially side-by-side
in the base body.
19. The tool head according to claim 17 wherein the disk clutch
is configured to couple two eccentrically arranged, axially parallel
projecting keylike clutch members and a clutch groove of the eccentric
disks.
20. The tool head according to claim 19 wherein the clutch member
for the outermost eccentric disk extends through an opening of the
innermost eccentric disk, which opening is configured as an elongate
hole.
21. The tool head according to claim 12 wherein the eccentric
disks have an opening surrounding the through opening.
22. The tool head according to claim 12 wherein the eccentric
disks are eccentrically supported in the base body in radial roller
bearings.
23. The tool head according to claim 17 wherein the disk clutch
is supported with respect to the base body through an axial thrust
and/or radial roller bearing.
24. The tool head according to claim 12 wherein the eccentric
disks rest against one another through axial slide bearings or roller
bearings.
25. The tool head according to claim 17 wherein each one of the
eccentric disks rests through an axial slide bearing or roller bearing
against the disk clutch or a front base body lid.
26. The tool head according to claim 1 wherein a calibrating mechanism
is provided for calibrating the zero position of the rotatable slide
mechanism with respect to the base body.
27. The tool head according to claim 26 wherein the calibrating
mechanism includes a counter which is arranged in the base body,
and which can be operated by a trip cam arranged on the driven side
of the transmission means or on one of the eccentric disks.
28. The tool head according to claim 26 wherein the calibrating
mechanism is configured to connect to an external microprocessor
arrangement with at least one electronically callable calibrating
table or calibrating curve for the coordination of the motor rotation
and the respective cutting blade radius.
29. The tool head according to claim 1 wherein the tool-receiving
means is adjusted in dependency of the respective angle of rotation
of the rotatable slide mechanism or of the cutting radius in order
to facilitate a finite alignment of the cutting tool relative to
the base-body axis with respect to the respective rotatable slide
mechanism.
30. The tool head according to claim 29 wherein the tool-receiving
means is adjusted by aligning a reference plane associated with
the cutting tool with the base-body axis and with respect to the
respective rotatable slide mechanism.
31. The tool head according to claim 29 wherein the tool-receiving
means are arranged rotatably about an axis parallel to the eccentric
axis of the rotatable slide mechanism oriented in an eccentric bore
of the respective rotatable slide mechanism.
32. The tool head for use in machine tools comprising a base body
coupled to a first machine spindle, and comprising at least one
slide mechanism coupled to a second spindle concentric to the first
machine spindle through transmission means arranged in the base
body, which is moved with respect to the base body, and carries
preferably a tool-receiving means for a cutting tool, wherein a
calibrating mechanism arranged in the base body for calibration
of the zero position of the at least one slide mechanism with respect
to the base body.
33. The tool head according to claim 32 wherein the calibrating
mechanism includes a calibration counter arranged in the base body
and operable through a trip cam arranged on the driven side of the
transmission means.
34. The tool head according to claim 32 wherein the calibrating
mechanism has a preferably external microprocessor arrangement with
at least one electronically callable calibrating table or calibrating
curve for the coordination of the relative rotation between the
first and second spindle and the cutting radius of the cutting tool
arranged on the slide.
35. The tool head for use in machine tools comprising a base body
coupled to a first machine spindle, and comprising at least one
slide mechanism coupled to a second spindle concentric to the first
machine spindle through transmission means arranged in the base
body, which is moved with respect to the base body, and carries
preferably a tool-receiving means for a cutting tool, wherein a
calibrating mechanism, which has an external microprocessor arrangement
with at least one electronically callable calibrating table or calibrating
curve for the coordination of the relative rotation between the
first and second spindle and the cutting radius of the cutting tool
arranged on the slide mechanism.
Machine tools description
FIELD OF THE INVENTION
The invention relates to a tool head for use in machine tools comprising
a base body coupled to a machine spindle, comprising at least one
tool-receiving means for a cutting tool, and comprising a rotatable
slide mechanism, which eccentrically carries the tool-receiving
means, and is rotated about an eccentric axis parallel to the base-body
axis with respect to the base body in order to facilitate an adjusting
of the cutting radius of the cutting tool.
BACKGROUND OF THE INVENTION
A tool head of this type is known from DE-A 197 02 219 in which
a rotatable slide mechanism is provided, which is arranged near
the center in the base body, and which can be adjusted through centrally
arranged transmission elements. The external machining of elongated
workpieces is not easily possible with this tool head.
SUMMARY OF THE INVENTION
Starting out from this, the basic purpose of the invention is to
provide a tool head which is compact and lightweight, and with which
also elongated workpieces can be machined with a high rotating speed.
The basic concept of the solution of the invention is that a second
rotatable slide mechanism is provided, which carries a second tool-receiving
means, and is rotated about a second eccentric axis parallel to
the base-body axis with respect to the base body in order to facilitate
an adjusting of the cutting radius of the respective cutting tool.
A preferred embodiment of the invention provides that transmission
means are arranged in the base body, which transmission means are
coupled to both rotatable slide mechanisms so that they can be driven
together with the adjustment of the reciprocal distance between
the two cutting tools. The transmission means can advantageously
be coupled to an additional machine spindle and can be driven by
a machine located drive motor. It is fundamentally possible to drive
the transmission means also with a drive motor integrated into the
base body. The drive motor can thereby be configured as a stepping
motor or as a servomotor. The transmission means have advantageously
a speed-reduction gearing configured as a harmonic-drive or planetary
transmission.
According to a further preferred embodiment of the invention, the
two rotatable slide mechanisms are arranged diametrically opposite
one another with reference to the base-body axis, and are adjusted
radially oppositely directed through the common transmission means.
A further preferred embodiment of the invention provides that the
base body has an axially central through opening, and that the transmission
means form a hollow-shaft unit enclosing the through opening.
A preferred embodiment provides that the rotatable slide mechanisms
each have an eccentric disk which is supported axially parallel
eccentrically in the base body, which are axially adjacent to one
another, and extend with axially parallel crank arms which carry
the tool-receiving means, through a front opening of the base body.
The outermost eccentric disk, which is adjacent to the front facing
side of the base body, has thereby advantageously an opening for
passage of the crank arm of the innermost eccentric disk. Since
the crank arms carry out a circular motion about the base-body axis
during operation of the rotatable slide mechanisms, the front-facing
openings of the base body are configured as elongate holes preferably
curved in their longitudinal extent. In order to cover the slotted
holes, the tool-receiving means can carry outside shields. The opening
in the outermost eccentric disk must have sufficient play of movement
for the crank arm of the innermost eccentric disk, and is therefore
advantageously also configured as a slotted hole.
A further advantageous development of the invention provides that
the transmission means is coupled to the eccentric disks of the
rotatable slide mechanisms through a common disk clutch concentrically
supported in the base body. A particularly compact design is achieved
when the eccentric disk and the disk clutch are arranged sandwichlike
axially side-by-side in the base body. The disk clutch engages advantageously
with two eccentrically arranged, axially parallel projecting keylike
clutch members received in a respective one of the clutch grooves
of the two eccentric disks. The clutch members form thereby a type
of gear teeth which are moved along the clutch grooves during rotation
of the disk clutch taking along the eccentric disks. The clutch
member for the outmost eccentric disk extends through an opening
of the innermost eccentric disk, which opening is preferably configured
as a slotted hole.
In order to keep the center of the tool head free for passage of
a workpiece or a sleeve, the eccentric disks and the disk clutch
have also an opening surrounding the through opening. The eccentric
disks of the rotatable slide mechanisms are advantageously supported
in radial roller bearings, which are preferably configured as needle
bearings, in the base body. Also the disk clutch can be supported
in axial and/or radial roller bearings in the base body. The eccentric
disks, which rest sandwichlike against one another, the disk clutch
and the front-side base body lid are advantageously supported against
one another through axial slide or roller bearings. In the case
of slide bearings, the respective parts can be provided with a friction-reducing
coating.
According to a preferred or alternative development of the invention,
it is possible to provide a calibrating mechanism in order to calibrate
the zero position of the at least one rotatable slide mechanism
or a linear slide mechanism, which calibrating mechanism includes
preferably a calibration counter arranged in the base body, which
counter can be operated, for example, by a trip cam arranged on
the driven side of the transmission means, the disk clutch or on
one of the eccentric disks, and emits a calibrating signal to an
external electronics of the calibrating mechanism. The calibrating
mechanism can furthermore have an external microprocessor arrangement,
which houses at least one electronically callable calibrating table
or calibrating curve for the coordination of the relative rotation
of the two spindles and the cutting radius.
A shifting of the masses does not result from the rotation of the
rotatable slide mechanisms so that balancing masses are not needed.
However, attention must be paid, when using rotatable slide mechanisms
that during the adjusting operation, to not only the distance of
the blades from the base-body axis that is changed but also the
alignment of the blades with respect to the axis of rotation. For
many cases of application this is indeed of a subordinate importance.
An improvement in this respect can, however, be achieved in such
a manner that the two tool-receiving means can be adjusted in dependency
of the respective angle of rotation of the rotatable slide mechanism
or of the cutting radius with a finite alignment of the cutting
tool relative to the base-body axis with respect to the rotary body
(compare DE-A 197 02 219). The tool-receiving means can be adjusted
for this purpose by aligning a reference plane associated with the
cutting tool with the base-body axis and with respect to the respective
rotatable slide mechanism. In order to make this possible, it is
suggested according to a preferred development of the invention
that the tool-receiving means are arranged rotatably about an axis
parallel to the eccentric axis of the rotatable slide mechanism
in an eccentric bore of the respective rotary slide.
The tool head of the invention is particularly suited for the external
machining, in particular for turning, cutting or contour turning
of elongated workpieces received in the central through opening,
in that the two cutting tools, which are diametrically opposite
one another with respect to the through opening, are adjusted at
their radial distance from one another by a common operation of
the rotatable slide mechanisms.
A further advantageous use of the tool head of the invention is
that the workpiece to be machined can be supported with respect
to the center of the tool head end of the machine spindle.
The tool head of the invention can furthermore be advantageously
utilized for receiving a sleeve in the center through opening for
centering of a workpiece to be machined. The tool head of the invention
is particularly suited for use in a machine tool with a double spindle,
which has two spindles arranged concentrically to one another, and
can be driven independently of one another.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be discussed in greater detail hereinafter in
connection with one exemplary embodiment, which is schematically
illustrated in the drawings, in which:
FIGS. 1a and 1b are two longitudinal cross-sectional views rotated
at 90.degree. relative to one another and illustrating a tool head
with a center through and two rotary slides, which can be driven
together;
FIGS. 2a and 2b are two cross-sectional views of the tool head
taken along the cross-sectional lines A--A and B--B of FIG. 1b;
and
FIG. 3 is a front view of the tool head according to FIGS. 1a and
1b.
DETAILED DESCRIPTION
The tool head 22 illustrated in the drawings is designated for
use in a machine tool having a double spindle system. The outer
spindle 10 of the double spindle system is rotatably supported in
the machine housing 14 via bearings 12 whereas the inner spindle
16 is concentrically and rotatably supported within the outer spindle
via bearings 18. The outer spindle 10 and the inner spindle 16 can
be driven about their common spindle axis 20 by not illustrated
machine located drive motors.
The tool head 22 has a base body 24 which is fixedly coupled to
the outer spindle 10 so that no relative movement occurs therebetween,
and an adjusting mechanism 26 which is arranged in the base body
24 and is fixedly coupled to the inner spindle 16 so that no relative
movement occurs therebetween, is provided for the two eccentrically
arranged tool-receiving means 28 30 arranged on the front facing
side of the tool head. Two cutting tools 32 are respectively coupled
to the two tool-receiving means 28 30 which cutting tools 32 in
the illustrated exemplary embodiment each carry a radially inwardly
extending cutting blade 34. A hollow base body-fixed sleeve 36 is
provided in the center of the tool head 22 which sleeve 36 provides
a central through opening 38 coaxial with the spindle axis 20 for
a workpiece to be machined or for a workpiece holder.
The two tool-receiving means 28 30 are adjustable with respect
to the base body 24 by the adjusting mechanism 26 facilitating an
adjusting of the cutting radius of the cutting tool 32. The tool-receiving
means 28 is for this purpose rigidly connected through an axially
extending crank arm 40 fixed to a rotatable circularly-shaped slide
plate 42 and the tool-receiving means 30 through an axially extending
crank arm 44 fixed to a rotatable circularly-shaped slide plate
46. Both rotatable slide plates 42 and 46 each have a central axis
of rotation that is eccentrically arranged relative to the spindle
axis 20 as shown at A.sub.1 and A.sub.2 in FIG. 3. In other words,
the slide plates 42 and 46 respectively define eccentric disks 48
and 50 which are arranged sandwichlike axially side-by-side in
different eccentric bearings defined by needle rings 52 54. The
crank arms 40 44 of the two rotatable slide plates extend through
kidney-shaped holes 56 58 in a base body lid 60. The kidney-shaped
holes 56 58 in the base body lid 60 are shielded to the outside
by shields 88 90 which laterally project over the tool-receiving
means 28 30. The crank arm 44 of the rotatable slide plate 46
which is the innermost slide plate, is furthermore guided through
a kidney-shaped hole 62 in the rotatable slide plate 42 which is
the outermost slide plate 42.
A disk clutch 64 is concentrically supported in the base body and
is provided for rotatably driving the rotatable slide plates 42
46 which disk clutch 64 engages on the one side thereof through
keylike clutch members 66 68 clutch grooves 70 72 on the eccentric
disks 48 50 and is connected on its other side to the driven side
74 of a speed-reduction gearing 76 of the adjustment mechanism 26.
The speed-reduction gearing 76 is designed as a harmonic-drive transmission.
The clutch member 66 which is coupled to the outermost eccentric
disk 48 is arranged on the front facing end of crank arm 78 which
extends through a kidney-shaped hole opening 80 in the innermost
eccentric disk 50. The speed-reduction gearing 76 is connected at
its input end 82 to rearwardly projecting driving pins 84 which
are fixedly coupled against relative rotation to the inner spindle
16. The disk clutch 64 is rotatably supported by an axial thrust
needle bearing 86 with respect to the base body, whereas axial thrust
slide bearings, which can be coated with a friction-reducing material,
are arranged at the separating planes 87', 87", 87'",
namely, between the disk clutch 64 and the innermost eccentric disk
50 the innermost eccentric disk 50 and the outermost eccentric
disk 48 and the outermost eccentric disk 48 and the base body lid
60.
In order to adjust the reciprocal radial distance between the cutting
blades 34 the inner spindle 16 is rotated relative to the base
body 24 about the spindle axis 20 by the machine control. The speed-reduction
gearing 76 changes the rotations of the spindle through the driven
side 74 into a finite angular rotation of the disk clutch 64 which
in turn rotates through the clutch members 66 68 the eccentric
disks 48 50 of the rotatable slide plates 42 46 to a corresponding
angle. The rotation results in an oppositely directed radius change
in the area of the tool-receiving means 28 30 which results in
a change of the cutting radii of the cutting blades 34 and thus
in a change of the distance between the cutting blades.
To calibrate the zero position of the adjusting range, a calibration
counter 92 is housed in the base body 24 which calibration counter
92 is operated by a trip cam arrangement 94 on the disk clutch 64
and emits during each operation a signal to a calibrating circuit
in the not illustrated machine control. The machine control includes
in addition a microprocessor arrangement with a calibrating table,
which can be called electronically, or a calibrating curve for the
coordination of the motor rotations and the respective blade radius.
In summary, the following is to be stated: The invention relates
to a tool head for use in machine tools comprising a base body 24
which is coupled to a machine spindle, comprising at least one tool-receiving
means 28 for a cutting tool 32 and comprising a rotatable slide
plate 42 which eccentrically carries the tool-receiving means and
is rotatable about an eccentric axis parallel to the base-body axis
and relative to the base body 24 in order to facilitate an adjusting
of the cutting radius, of the cutting tool. According to the invention,
a second rotatable slide plate 46 is provided which carries a second
eccentric tool-receiving means 30 and is rotatable about a second
eccentric axis parallel to the base-body axis, and relative to the
base body 24 in order to facilitate an adjusting of the cutting
radius of the respective cutting tool 32. Transmission means 76
74 are furthermore housed in the base body, through which transmissions
means 76 74 the two rotatable slide plates 42 46 are simultaneously
driven.
Although a particular preferred embodiment of the invention has
been disclosed in detail for illustrative purposes, it will be recognized
that variations or modifications of the disclosed apparatus, including
the rearrangement of the parts, lie within the scope of the present
invention. |