The invention relates to a tool-holding module that is swivelable and is mountable on a tool-holding turret of a numerically controlled lathe.

With reference to Figures 1 to 3, a swiveling tool-holding module 1 of known type is disclosed.

The tool-holding module 1 is of driven type inasmuch as it is provided with a drive shaft 2 that is connectable in a releasable manner to a drive, which is not shown, of a tool- holding turret 3 (Figure 3). The tool-holding module 1 further includes a supporting body 4 that is fixable by screws 5 to the tool -holding turret 3, and rotatably supports the drive shaft 2. Also, the tool-holding module 1 comprises a main body 6, which is rotatably connected to the supporting body 4, for supporting a cutting tool, which is not shown, for example a drill.

More precisely the main body 6 is rotatable, with respect to the supporting body 4, around a rotation axis A, in the embodiment in Figures 1 to 3 the rotation axis A being perpendicular to a drive axis B of the drive shaft 2.

The tool-holding module 1 further comprises an arc-shaped nonius 7, for indicating a relative angular position between the main body 6 and the supporting body 4. The nonius 7 includes a graduated scale 8, that is integral with the main body 6, and a reference mark 9, made on the supporting body 4. The reference mark 9 and the graduated scale 8 cooperate to indicate a relative angular position between the main body 6 and the supporting body 4.

Also, the tool-holding module 1 is provided with fixing screws 10 for fixing, in a set angular position, the main body 6 to the supporting body 4.

In use, in order to adjust an angular position of the main body 6 with respect to the supporting body 4, it is necessary to perform the following operations:

a. unloosening the fixing screws 10;

b. rotating around the rotation axis A the main body 6 with respect to the supporting body 4 until the nonius 7 indicates a desired angular position (determined by a target angle α^);

c. screwing, without tightening, the fixing screws 10;

d. fixing the tool-holding module 1 on the tool-holding turret 3;

e. fixing a dial gauge 11 to a base, which is not shown, of the lathe;

f. bringing the dial gauge 11 into contact with an abutting surface 12 of the main body 6, the abutting surface 12 being a ground surface that replicates, on a parallel plane, the position of an axis C of the cutting tool, which is not shown;

g. resetting the dial gauge 11 , moving the tool-holding turret 3 along an axis Z by a preset value ΔΖ, reading on a dial 13 of the dial gauge 11 a value ΔΧ measured by the dial gauge 11 along an axis X, which is perpendicular to the axis Z;

h. calculating with the formula a _rea i = arctan(AZ/AX) the real rotation angle of the main body 6 with respect to the supporting body 4;

i. tightening the fixing screws 10 if a _rea i ⁼ oitarget, otherwise repeating steps a. to L Driven tool-holding modules on which it is not possible to make the abutting surface, for example tool-holding modules supporting a hob are also known. For the latter, in order to adjust an angular position of the main body with respect to the supporting body, it is necessary, before step a., to disassemble the hob from the main body. Also, for this type of tool-holding module, step f. comprises bringing the dial gauge into contact with a surface of a shaft supporting the hob. Alternatively, in other cases of driven tool-holding modules on which it is not possible to make the abutting surface, between step d. and step e., on the main body, a ground cylinder is mounted that will act as the abutting surface for the dial gauge.

It should be noted how the operations disclosed above in order to adjust an angular position of the main body 6 with respect to the supporting body 4, in particular operations f. to i., are performed with the tool-holding module 1 mounted on the tool-holding turret 3, are extremely slow and laborious to perform and in practice have to be repeated several times in order to obtain precise adjustment, this entailing lengthy machine downtime, with consequent reduction of the productivity of the lathe.

An object of the present invention is to improve tool-holding modules, in particular swiveling tool-holding modules.

A further object is to provide a tool-holding module wherein it is possible to adjust simply, fast and accurately a relative angular position between the main body and the supporting body.

Such objects and still others are obtained by a tool-holding module according to one or more of the claims set out below.

The invention can be better understood and implemented with reference to the attached drawings that illustrate some embodiments thereof by way of non-limiting example, wherein: - Figures 1 to 3 are axonometric views of a tool-holding module of known type;

- Figure 4 is an axonometric view of a tool-holding module according to the invention;

- Figure 5 is a view like that in Figure 4 partially exploded;

- Figures 6 to 8 are orthogonal views of an electronic device included in the tool- holding module of Figure 4;

Figure 9 is an axonometric view of another tool-holding module according to the invention;

Figure 10 is an axonometric view of still another tool-holding module according to the invention;

- Figure 11 is an axonometric view of a further tool-holding module according to the invention;

- Figure 12 is a view like that in Figure 11 partially exploded;

- Figure 13 is an axonometric view of another further tool-holding module according to the invention; and

- Figure 14 is a view like that in Figure 13 partially exploded.

With reference to Figures 4 to 8, there is disclosed a swiveling tool-holding module 100 according to the invention.

The tool-holding module 100 is of driven type inasmuch as it is provided with a drive shaft 102 that is connectable in a releasable manner to a drive, which is not shown, of a tool-holding turret, which is not shown. The tool-holding module 100 includes a supporting body 104 that is fixable by screws 105 to the tool-holding turret, and rotatably supports the drive shaft 102. Also, the tool-holding module 100 comprises a main body 106, which is rotatably connected to the supporting body 104, for supporting a cutting tool, which is not shown, for example a drill.

More precisely, the main body 106 is rotatable, with respect to the supporting body 104, around a rotation axis A that is transverse, in particular perpendicular, to a drive axis B of the drive shaft 102.

The tool-holding module 100 further comprises indicating means 107 for indicating a relative angular position between the main body 106 and the supporting body 104.

The indicating means 107 comprises reading scale means 108, sensor means 109 (Figures 6 to 8) for reading the reading scale means 108, and display means 110 for displaying a value of the angular position read by sensor means 109 on the reading scale means 108. The reading scale means 108 is supported by or embedded in, a revolution surface 111 of, or that is integral with, the main body 106.

In this context, a revolution surface is defined as a surface obtained by rotating a curve around the rotation axis A.

In particular, the tool-holding module 100 shown in Figures 4 and 5, has a cylindrical revolution surface 111, extending around and parallel to the rotation axis A of the main body 106.

The reading scale means 108 is reading scale means that is readable electronically, for example of optical, or magnetic or capacitive or resistive type or of other type.

The aforesaid sensor means 109 is included in an electronic device 112, for example made of plastics, which is fixable, for example by a threaded connection, to a supporting surface 113 of the supporting body 104.

In particular, the sensor means 109 faces the reading scale means 108 and is configured for reading the latter, whether it be of optical, or magnetic or capacitive or resistive type or of other type.

The aforesaid display means 110 is included in the electronic device 112 and comprises a digital display 114, for example of the LED (Light Emitting Diode) type or of the LCD (Liquid Crystal Display) type, or of the OLED (Organic Light Emitting Diode) type, or of the e-ink (electrophoretic ink) type, on which is displayable a value 115 of the angular position read by the sensor means 109 on the reading scale means 108, and optionally, a charge value of battery means, which is not shown, included in the indicating means 107. In particular, the battery means is housed in the electronic device 112 and supplies the sensor means 109, the display means 110 and data processing electronics of the indicating means 107 that is also included in the electronic device 112.

The battery means is designed to run for at least one or two years.

The aforesaid data processing electronics can comprise, optionally, a microprocessor for storing the set angular positions, or for storing a number identifying the cutting tool used. Also, optionally, the microprocessor can be reprogrammable according to the radius of the revolution surface 111, this increasing the flexibility of the indicating means 107.

Also, the electronic device 112 can be provided with keys for making the electronic device 112 work, for example for switching on/off the electronic device 112, for resetting the display means 110, for interacting with the microprocessor, etc..

Alternatively, the display means 110 can comprise a "touch" type interface for performing the aforesaid operations.

Also, the indicating means 107 can be configured for acquiring an absolute value on the reading scale means 108 representing an absolute position of the main body 106 with respect to the supporting body 104, or for acquiring a relative value on the reading scale means 108 representing a relative position of the main body 106 with respect to the supporting body 104, these positions being storable in the microprocessor.

Also, the tool-holding module 100 is provided with fixing screws 116 for fixing, in a set angular position, the main body 106 to the supporting body 104.

Further, the tool-holding module 100 comprises conduit means 117 fixed to the main body 106 and configured for conveying, in use, a cooling-lubricating fluid to a machining zone of the cutting tool.

In use, in order to adjust an angular position of the main body 106 with respect to the supporting body 104 it is sufficient to perform the following operations:

a. unloosening the fixing screws 116;

b. rotating around the rotation axis A the main body 106 with respect to the supporting body 104 until on the display means 110 the desired angle is displayed;

c. tightening the fixing screws 116.

It should be noted how operations a. to c. are performable outside the lathe, i.e. with the tool-holding module 100, on which the cutting tool can already be fixed, fixed to a workbench and not to the tool-holding turret.

It should be noted how owing to the tool-holding module 100 the operations for adjusting an angular position of the main body 106 with respect to the supporting body 104 are easy and simple to perform and enable a precise adjustment to be obtained, where "precise" is defined as being of the order of a tenth of a degree.

With reference to Figure 9 there is shown another swiveling tool-holding module 200 made according to the invention, configured for supporting a cutting tool, which is not shown, for making worm screws.

The tool-holding module 200 is of driven type inasmuch as it is provided with a drive shaft 202 that is connectable in a releasable manner to a drive, which is not shown, of a tool-holding turret, which is not shown. The tool-holding modules 200 include a supporting body 204 that is fixable by screws 205 to the tool-holding turret, and rotatably supports the drive shaft 202. Also, the tool-holding module 200 comprises a main body 206, which is rotatably connected to the supporting body 204, for supporting the cutting tool.

More precisely, the main body 206 is rotatable, with respect to the supporting body 104, around rotation axis A parallel to a drive axis B of the drive shaft 202.

The tool-holding module 200 further comprises indicating means 207 for indicating a relative angular position between the main body 206 and the supporting body 204.

The indicating means 207 comprises reading scale means 208, sensor means 209, shown by a dotted line, for reading the reading scale means 208, and display means 210 for displaying a value of the angular position read by the sensor means 209 on the reading scale means 208.

The reading scale means 208 is supported by or embedded in a revolution surface 211 of, or that is integral with, the supporting body 204.

In particular, the tool-holding module 200 shown in Figure 9, has a revolution surface 211 in the shape of a circular crown, extending around, and perpendicularly, to the rotation axis A of the main body 206.

The reading scale means 208 is a reading scale means that is readable electronically, for example of optical, or magnetic or capacitive or resistive type or of other type.

The aforesaid sensor means 209 is included in an electronic device 212, for example made of plastics, which is fixable, for example by a threaded connection, to a supporting surface 213 of the main body 206.

In particular, the sensor means 209 faces the reading scale means 208 and is configured for reading the latter, whether it be of optical, or magnetic or capacitive or resistive type or of other type.

The aforesaid display means 210 is included in the electronic device 212 and comprises a digital display 214, for example of the LED (Light Emitting Diode) type or of the LCD (Liquid Crystal Display) type, or of the OLED (Organic Light Emitting Diode) type, or of the e-ink (electrophoretic ink) type, on which is displayable a value 215 of the angular position read by the sensor means 209 on the reading scale means 208, and optionally, a charge value of battery means, which is not shown, included in the indicating means 207. In particular, the battery means is housed in the electronic device 212 and supplies the sensor means 209, the display means 210 and data processing electronics of the indicating means 207 that is also included in the electronic device 212.

The battery means is designed to run for at least one or two years.

The aforesaid data processing electronics can comprise, optionally, a microprocessor for storing the set angular positions, or for storing a number identifying the cutting tool used. Also, optionally, the microprocessor can be reprogrammable according to the radius of the revolution surface 211, this increasing the flexibility of the indicating means 207.

Also, the electronic device 212 can be provided with keys for making the electronic device 212 work, for example for switching on/off the electronic device 212, for resetting the display means 210, for interacting with the microprocessor, etc..

Alternatively, the display means 210 can comprise a "touch" type interface for performing the aforesaid operations.

Also, the indicating means 207 can be configured for acquiring an absolute value on the reading scale means 208 representing an absolute position of the main body 206 with respect to the supporting body 204, or for acquiring a relative value on the reading scale means 208 representing a relative position of the main body 206 with respect to the supporting body 204, these positions being storable in the microprocessor.

Also, the tool-holding module 200 is provided with fixing screws 216 for fixing, in a set angular position, the main body 206 to the supporting body 204.

Further, the tool-holding module 200 comprises conduit means 217 fixed to the main body 206 and configured for conveying, in use, a cooling-lubricating fluid to a machining zone of the cutting tool.

Also here, in order to adjust an angular position of the main body 206 with respect to the supporting body 204, it is sufficient to perform the following operations:

a. unloosening the fixing screws 216;

b. rotating around the rotation axis A the main body 206 with respect to the supporting body 204 until on the display means 210 the desired angle is displayed; c. tightening the fixing screws 216.

With reference to Figure 10, there is shown still another swiveling tool-holding module 300 made according to the invention, configured for supporting a hob 330 for making bevelled toothing.

The tool-holding module 300 is of driven type inasmuch as it is provided with a drive shaft 302 that is connectable in a releasable manner to a drive, which is not shown, of a tool-holding turret, which is not shown. The tool-holding module 300 includes a supporting body 304 that is fixable by screws 305 to the tool-holding turret, and rotatably supports the drive shaft 302. Also, the tool-holding module 300 comprises a main body 306, which is rotatably connected to the supporting body 304, for supporting the hob 330. More precisely, the main body 306 is rotatable, with respect to the supporting body 304, around rotation axis A parallel to a drive axis B of the drive shaft 302.

The tool-holding module 300 further comprises indicating means 307 for indicating a relative angular position between the main body 306 and the supporting body 304.

The indicating means 307 comprises reading scale means 308, sensor means 309, shown by a dotted line, for reading the reading scale means 308, and display means 310 for displaying a value of the angular position read by the sensor means 309 on the reading scale means 308.

The reading scale means 308 is supported by or embedded in, a revolution surface 311 of, or that is integral with, the main body 306.

In particular, the tool-holding module 300 shown in Figure 10, has a cylindrical revolution surface 311, extending around and parallel to the rotation axis A of the main body 306.

The reading scale means 308 is reading scale means that is readable electronically, for example of optical, or magnetic or capacitive or resistive type or of other type.

The aforesaid sensor means 309 is included in an electronic device 312, for example made of plastics, which is fixable, for example by a threaded connection, to a supporting surface 313 of the supporting body 304.

In particular, the sensor means 309 faces the reading scale means 308 and is configured for reading the latter, whether it be of optical, or magnetic or capacitive or resistive type or of other type.

The aforesaid display means 310 is included in the electronic device 312 and comprises a digital display 314, for example of the LED (Light Emitting Diode) type or of the LCD (Liquid Crystal Display) type, or of the OLED (Organic Light Emitting Diode) type, or of the e-ink (electrophoretic ink) type, on which is displayable a value 315 of the angular position read by the sensor means 309 on the reading scale means 308, and optionally, a charge value of battery means, which is not shown, included in the indicating means 307. In particular, the battery means is housed in the electronic device 312 and supplies the sensor means 309, the display means 310 and data processing electronics of the indicating means 307 that is also included in the electronic device 312.

The battery means is designed to run for at least one or two years.

The aforesaid data processing electronics can comprise, optionally, a microprocessor for storing the set angular positions, or for storing a number identifying the cutting tool used. Also, optionally, the microprocessor can be reprogrammable according to the radius of the revolution surface 311, this increasing the flexibility of the indicating means 307.

Also, the electronic device 312 can be provided with keys for making the electronic device 312 work, for example for switching on/off the electronic device 312, for resetting the display means 310, for interacting with the microprocessor, etc..

Alternatively, the display means 310 can comprise a "touch" type interface for performing the aforesaid operations.

Also, the indicating means 307 can be configured for acquiring an absolute value on the reading scale means 308 representing an absolute position of the main body 306 with respect to the supporting body 304, or for acquiring a relative value on the reading scale means 308 representing a relative position of the main body 306 with respect to the supporting body 304, these positions being storable in the microprocessor.

Also, the tool-holding module 300 is provided with fixing screws 316 for fixing, in a set angular position, the main body 306 to the supporting body 304.

Further, the tool-holding module 300 comprises conduit means, which is not shown, fixed to the main body 306 and configured for conveying, in use, a cooling-lubricating fluid to a machining zone of the hob 330.

Also here, in order to adjust an angular position of the main body 306 with respect to the supporting body 304, it is sufficient to perform the following operations:

a. unloosening the fixing screws 316;

b. rotating around the rotation axis A the main body 306 with respect to the supporting body 304 until on the display means 310 the desired angle is displayed; c. tightening the fixing screws 316.

With reference to Figures 11 and 12, there is shown a further swiveling tool-holding module 400 made according to the invention.

The tool-holding module 400 is of driven type inasmuch as it is provided with a drive shaft 402 that is connectable in a releasable manner to a drive, which is not shown, of a tool-holding turret, which is not shown. The tool-holding module 400 includes a supporting body 404 that is fixable by screws 405 to the tool-holding turret, and rotatably supports the drive shaft 402. Also, the tool-holding module 400 comprises a main body 406, which is rotatably connected to the supporting body 404, for supporting a cutting tool, which is not shown, for example a drill.

More precisely, the main body 406 is rotatable, with respect to the supporting body 404, around a rotation axis A that is transverse, in particular perpendicular to a drive axis B of the drive shaft 402.

The tool-holding module 400 further comprises indicating means 407 for indicating a relative angular position between the main body 406 and the supporting body 404.

The indicating means 407 comprises reading scale means 408, sensor means 409, shown by a dotted line, for reading the reading scale means 408, and display means 410 for displaying a value of the angular position read by the sensor means 409 on the reading scale means 408.

The reading scale means 408 comprises a magnetised ring 441 fixed by grub screws, which are not shown, to a measuring shaft 440 that is integral with the main body 406 and extends parallel to the rotation axis A.

The magnetised ring 441 comprises a plurality of magnetic poles embedded in a revolution surface 411 of the magnetised ring 441.

In particular, the revolution surface 411 is cylindrical and extends around, and parallel, to the rotation axis A of the main body 406.

The reading scale means 408 is reading scale means of magnetic type that is readable electronically.

The magnetised ring 441 is rotationally supported by an electronic device 412, for example made of plastics, supported by the supporting body 404.

In particular, the electronic device 412 is provided with an anti -rotation pin, which is not shown, arranged for engaging in a passage 442, made on a supporting surface 413 of the supporting body 404, to prevent the electronic device 412, in use, from rotating around the rotation axis A.

The aforesaid sensor means 409 is included in the electronic device 412, faces the reading scale means 408 and is configured for reading the latter.

The aforesaid display means 410 is included in the electronic device 412 and comprises a digital display 414, for example of the LED (Light Emitting Diode) type or of the LCD (Liquid Crystal Display) type, or of the OLED (Organic Light Emitting Diode) type, or of the e-ink (electrophoretic ink) type, on which is displayable a value 415 of the angular position read by the sensor means 409 on the reading scale means 408, and optionally, a charge value of battery means, which is not shown, included in the indicating means 407.

In particular, the battery means is received in the electronic device 412 and supplies the sensor means 409, the display means 410 and data processing electronics of the indicating means 407 that is also included in the electronic device 412. The battery means is designed to run for at least one or two years.

The aforesaid data processing electronics can comprise, optionally, a microprocessor for storing the set angular positions, or for storing a number identifying the cutting tool used. Also, optionally, the microprocessor can be reprogrammable according to the radius of the revolution surface 411, this increasing the flexibility of the indicating means 407.

Also, the electronic device 412 can be provided with keys for making the electronic device 412 work, for example for switching on/off the electronic device 412, for resetting the display means 410, for interacting with the microprocessor, etc..

Alternatively, the display means 410 can comprise a "touch" type interface for performing the aforesaid operations.

Also, the indicating means 407 can be configured for acquiring an absolute value on the reading scale means 408 representing an absolute position of the main body 406 with respect to the supporting body 404, or for acquiring a relative value on the reading scale means 408 representing a relative position of the main body 406 with respect to the supporting body 404, these positions being storable in the microprocessor.

Also, the tool -holding module 400 is provided with fixing screws 416 for fixing, in a set angular position, the main body 406 to the supporting body 404.

Further, the tool-holding module 400 comprises conduit means 117 fixed to a free end of the measuring shaft 440 and configured for conveying, in use, a cooling-lubricating fluid to a machining zone of the cutting tool.

Also here, in order to adjust an angular position of the main body 406 with respect to the supporting body 404, it is sufficient to perform the following operations:

a. unloosening the fixing screws 416;

b. rotating around the rotation axis A the main body 406 with respect to the supporting body 404 until on the display means 410 the desired angle is displayed;

c. tightening the fixing screws 416.

With reference to Figures 13 and 14 there is shown another further swiveling tool-holding module 500 made according to the invention.

The tool-holding module 500 is of driven type inasmuch as it is provided with a drive shaft 502 that is connectable in a releasable manner to a drive, which is not shown, of a tool-holding turret, which is not shown. The tool-holding module 500 includes a supporting body 504 that is fixable by screws 505 to the tool-holding turret, and rotatably supports the drive shaft 502. Also, the tool-holding module 500 comprises a main body 506, which is rotatably connected to the supporting body 504, for supporting a cutting tool, which is not shown, for example a drill.

More precisely the main body 506 is rotatable, with respect to the supporting body 504, around a rotation axis A that is transverse, in particular perpendicular, to a drive axis B of the drive shaft 502.

The tool-holding module 500 further comprises indicating means 507 for indicating a relative angular position between the main body 506 and the supporting body 504.

The indicating means 507 comprises reading scale means 508, sensor means 509, shown by a dotted line, for reading the reading scale means 508, and display means 510 for displaying a value of the angular position read by the sensor means 509 on the reading scale means 508.

The reading scale means 508 is supported by or embedded in, a revolution surface 511 of, or that is integral with, the main body 506.

In particular, the tool-holding module 500 shown in Figures 13 and 14 has a revolution surface 511 in the shape of a circular crown, extending around, and perpendicularly, to the rotation axis A of the main body 506.

The reading scale means 508 is reading scale means that is readable electronically, for example of optical, or magnetic or capacitive or resistive type or of other type.

The aforesaid sensor means 509 is included in an electronic device 512, for example made of plastics, which is fixable, for example by a threaded connection, to a supporting surface 513 of the supporting body 504.

In particular, the sensor means 509 faces the reading scale means 508 and is configured for reading the latter, whether it be of optical, or magnetic or capacitive or resistive type or of other type.

The aforesaid display means 510 is included in the electronic device 512 and comprises a digital display 514, for example of the LED (Light Emitting Diode) type or of the LCD (Liquid Crystal Display) type, or of the OLED (Organic Light Emitting Diode) type, or of the e-ink (electrophoretic ink) type, on which is displayable a value 515 of the angular position read by the sensor means 509 on the reading scale means 508, and optionally, a charge value of battery means, which is not shown, included in the indicating means 507.

In particular, the battery means is received in the electronic device 512 and supplies the sensor means 509, the display means 510 and data processing electronics of the indicating means 507 that is also included in the electronic device 512. The battery means is designed to run for at least one or two years.

The aforesaid data processing electronics can comprise, optionally, a microprocessor for storing the set angular positions, or for storing a number identifying the cutting tool used. Also, optionally, the microprocessor can be reprogrammable according to the radius of the revolution surface 511, this increasing the flexibility of the indicating means 507.

Also, the electronic device 512 can be provided with keys for making the electronic device 512 work, for example for switching on/off the electronic device 512, for resetting the display means 510, for interacting with the microprocessor, etc..

Alternatively, the display means 510 can comprise a "touch" type interface for performing the aforesaid operations.

Also, the indicating means 507 can be configured for acquiring an absolute value on the reading scale means 508 representing an absolute position of the main body 506 with respect to the supporting body 504, or for acquiring a relative value on the reading scale means 508 representing a relative position of the main body 506 with respect to the supporting body 504, these positions being storable in the microprocessor.

Also, the tool-holding module 500 is provided with fixing screws 516 for fixing, in a set angular position, the main body 506 to the supporting body 504.

Further, the tool-holding module 500 comprises conduit means 517 fixed to the main body 506 and configured for conveying, in use, a cooling-lubricating fluid to a machining zone of the cutting tool.

Also here, in order to adjust an angular position of the main body 506 with respect to the supporting body 504, it is sufficient to perform the following operations:

a. unloosening the fixing screws 516;

b. rotating around the rotation axis A the main body 506 with respect to the supporting body 504 until on the display means 510 the desired angle is displayed;

c. tightening the fixing screws 516.

It should be noted how in the aforesaid description reference has been made to a tool- holding module 100, 200, 300, 400, 500 of driven type. Nevertheless, the invention is not limited to such types of tool-holding module but can also be applied to non-driven tool- holding modules, i.e. which are devoid of drive shafts that are connectable in a releasable manner to a drive of a tool-holding turret.