CLAMPING DEVICE, SENSOR MODULE AND SENSOR ASSEMBLY

Abstract

The invention relates to a clamping device (I) for clamping a component, more particularly for fastening a tool to a machine tool, comprising: a main body (2), which defines a clamping axis (X) and in the front end region of which a clamping region (3) for a component to be clamped, more particularly for a tool shaft, is located; a sensor module (IO), which is in the form of a construction unit; wherein the sensor module (IO) is inserted into the receiving space (9) and is retained therein.

Claims

1-43. (canceled)

44. Clamping device (1) for clamping a component, in particular for fixing a tool on a machine tool, with a base body (2) defining a clamping axis (X), at the front end region of which is arranged a clamping region (3) for a component to be clamped, in particular for a tool shank, wherein a receiving space (9) for a sensor module (10) is formed in the base body (2), which is open to a peripheral surface of the base body (2) and extends radially into the base body (2) starting therefrom, and a sensor module (10), which is designed as a structural unit and comprises a tubular sensor housing (14), which defines a sensor axis (Y), a closure cover (23), which firmly closes the sensor housing (14) at one end face, a sensor element (31) accommodated within the sensor housing (14) for detecting operating parameters and a data transmission device (32) connected to the sensor element (31) for the wireless transmission of measurement data recorded by the sensor element (31) to a receiver located outside the clamping device (1), wherein the sensor module (10) is inserted into the receiving space (9) and held therein in such a way that the closure cover (23) faces outwards.

45. Clamping device (1) according to claim 44, wherein the data transmission device (32) is integrated in the closure cover (23), wherein, preferably the data transmission device (32) comprises an antenna (33), in particular cast into the closure cover, with an earth pole (34) and an antenna pole (35).

46. Clamping device (1) according to claim 45, wherein the earth pole (34) is connected or can be connected to the sensor housing (14) in an electrically conductive manner, and/or in that the earth pole (34) and the antenna pole (35) are designed in the form of a disc, in particular with a circular outer shape in the closure cover (23), the two poles (34, 35) extending in particular parallel to one another, preferably perpendicular to the sensor axis (Y), wherein, preferably, the antenna pole (35) is arranged adjacent to the outwardly facing end face of the closure cover (23) and the earth pole (34) is located on the inside of the antenna pole (35) in the closure cover (23), in particular in the region of an annularly circumferential outer collar (25) of the closure cover, wherein, preferably, the antenna pole is connected to an electrical conductor which, starting from the antenna pole, leads into the interior of the sensor housing, in particular to a circuit board, and the earth pole has a through-hole through which the electrical conductor runs electrically insulated from the earth pole, wherein, in particular, honeycomb-shaped openings (36) are formed in the antenna pole (35) and/or the earth pole (34), and the honeycomb-shaped openings (36) are filled with material, in particular with a plastic.

47. Clamping device (1) according to claim 44, wherein it further comprises a power supply unit (26) for supplying the sensor module (10) with power.

48. Clamping device (1) according to claim 47, wherein the energy supply unit (26) is accommodated as a separate component in the receiving space (9), wherein, in particular, the energy supply unit (26) is arranged at the inner end of the receiving space (9) and a shim (27) is arranged between the energy supply unit (26) and the sensor module (10) in order to position the sensor element (31) on the clamping axis (X), wherein, preferably, the sensor module (10) has two externally accessible electrical charging contacts (28, 29), which are each electrically connected or connectable to corresponding contacts on the energy supply unit (26) and are electrically insulated from one another in order to be able to supply the energy supply unit (26) with voltage and/or current and charge it by contacting the two electrical charging contacts (28, 29) with the poles of a charging device.

49. Clamping device (1) according to claim 48, wherein a first electrical charging contact (28), in particular for applying a negative pole of a charger, is arranged in the closure cover (23), preferably centrally in the closure cover (23), and a second electrical charging contact (29), in particular for applying a positive pole of a charger, is formed by the externally accessible end face of the sensor housing (14).

50. Clamping device (1) according to claim 49, wherein the first electrical charging contact (28) is electrically conductively connected to the antenna pole (35), in particular is formed by a contact region (39) formed on the antenna pole (35), which is open to the outside.

51. Clamping device (1) according to claim 44, wherein the receiving space (9) intersects the clamping axis (X), but does not completely penetrate the base body (2) radially, and/or in that the sensor element (31) is arranged inside the sensor housing (14) in such a way that it lies on the clamping axis (X), and/or in that the sensor module (10) has a circuit board (30) which is arranged inside the sensor housing (14) and carries the sensor element (31), the circuit board (30) preferably running parallel to the sensor axis (Y) and containing data processing means for processing the measurement signals provided by the sensor element (31), and/or in that the base body (2) has at least one coolant channel (11) for conducting coolant from a rear machine interface of the base body (2) forwards to the clamping region (3), at least one coolant channel (11) intersecting the receiving space (9), so that the receiving space (9) divides the coolant channel (11) into a front channel section (12) and a rear channel section (13), and in that an annular circumferential coolant groove (19) is formed in the outer circumferential surface of the sensor housing (14), so that coolant which is conducted to the clamping region (3) can flow past the sensor housing (14) from the rear channel section to the front channel section through the coolant groove (19).

52. Clamping device (1) according to claim 51, wherein sealing means are provided to seal the gap between the sensor housing (14) of the sensor module (10) and the wall of the receiving space (9) on both sides of the coolant groove (19), wherein, in particular, on both sides next to the coolant groove (19) an annular circumferential sealing groove (20, 21) is formed in the sensor housing (14), into which sealing rings (22) are inserted and are pressed against the wall of the receiving space (9).

53. Clamping device (1) according to claim 44, wherein the sensor module (10) is screwed into the base body (2), an external thread (17) being preferably formed on the sensor housing (14), which is screwed into a corresponding internal thread (15) of the receiving space (9), wherein, in particular, engagement means for a tool are formed in the sensor housing (14) in order to be able to screw the sensor module (10) into the receiving space (9), wherein, preferably, the engagement means comprise several, in particular three, recesses (18) distributed along the circumference and open outwards towards the closed end face and radially to the sensor axis (Y), which recesses preferably extend into the thread.

54. Clamping device (1) according to claim 44, wherein a radially inwardly projecting annular collar (24) is provided at the closed end region of the sensor housing (14), which collar engages behind a corresponding annularly circumferential outer collar (25) of the closure cover (23), so that the closure cover (23) is held positively on the sensor housing (14), and/or in that the receiving space (9) has a circular cross-section, the diameter of the receiving space (9) preferably being larger than the diameter of the at least one coolant channel (11).

55. Sensor module (10), in particular for a clamping device (1) according claim 44, wherein the sensor module (10) is designed as a structural unit and comprises a tubular sensor housing (14) which defines a sensor axis (Y), a closure cover (23), which firmly closes the sensor housing (14) at one end, a sensor element (31) accommodated within the sensor housing (14) for recording measurement data and a data transmission device (32) connected to the sensor element (31) for the wireless transmission of measurement data recorded by the sensor element (31) to a receiver located outside the clamping device (1), wherein the data transmission device (32) is integrated into the closure cover (23), and/or in that the sensor module (10) has two externally accessible electrical charging contacts (28, 29) which can each be electrically connected to corresponding contacts of a power supply unit (26) and are at the same time electrically insulated from one another, in order to be able to supply the power supply unit (26) with voltage and/or current and charge it by contacting the electrical charging contacts (28, 29) with a charger in order to be able to supply the power supply unit (26) with voltage and/or current and charge it, a first electrical charging contact (28) being preferably arranged in the closure cover (23), preferably centrally in the closure cover (23), in particular for applying a negative pole of a charger, and a second electrical charging contact (29), in particular for applying a positive pole of a charger, being formed by the end face of the sensor housing (14) on the closure cover side.

56. Sensor module (10) according to claim 55, wherein the data transmission device (32) comprises an antenna (33) integrated in the closure cover (23), in particular cast into the latter, with an earth pole (34) and an antenna pole (35), wherein, in particular, the earth pole (34) is connected or can be connected to the sensor housing (14) in an electrically conductive manner, wherein, preferably, the earth pole (34) and the antenna pole (35) are formed in the form of a disc, in particular with a circular outer shape in the closure cover (23), the two poles (34, 35) extending in particular parallel to one another, preferably perpendicular to the sensor axis (Y).

57. Sensor module (10) according to claim 56, wherein the antenna pole (35) is arranged adjacent to the outwardly facing end face of the closure cover (23) and the earth pole (34) is located on the inside of the antenna pole (35) in the closure cover (23), in particular in the region of an annularly circumferential outer collar (25) of the closure cover (23), wherein, in particular, the antenna pole (35) is connected to an electrical conductor (37) which, starting from the antenna pole (35), leads into the interior of the sensor housing (14), and the earth pole (34) has a through-hole (38) through which the electrical conductor (37) runs electrically insulated from the earth pole (34) and/or wherein the antenna pole (35) and/or the earth pole (34) are formed with honeycomb-shaped openings (36), and the honeycomb-shaped openings (36) are filled with material, in particular with a plastic.

58. Sensor module (10) according to claim 55, wherein the sensor element (31) is arranged within the sensor housing (14) in such a way that it can be placed on the clamping axis (X) of a clamping device (1), and/or in that the sensor module (10) comprises a circuit board (30) which is arranged within the sensor housing (14) and carries the sensor element (31), the circuit board (30) preferably extending through the sensor axis (Y) and including data processing means for processing the measurement signals provided by the sensor element (31), and/or in that an annular circumferential coolant groove (19) is formed in the outer circumferential surface of the sensor housing (14), wherein, in particular, an annular circumferential sealing groove (20, 21) is formed on both sides of the coolant groove (19), into which sealing rings (22) can be inserted.

59. Sensor module (10) according to claim 55, wherein an external thread (17) is formed on the sensor housing (14), and/or in that engagement means for a tool are formed in the sensor housing (14) in order to be able to screw the sensor module (10) into a receiving space (9) of a clamping device (1), wherein, in particular, the engagement means comprise several, in particular three, recesses (18) distributed along the circumference and open towards the closed end face and radially outwards to the longitudinal axis, which recesses preferably extend into the external thread (17).

60. Sensor module (10) according to claim 55, wherein a radially inwardly projecting annular collar (24) is provided on the sensor housing (14), which collar engages behind a corresponding outer collar (25) of the closure cover (23), so that the closure cover (23) is held positively on the sensor housing (14).

61. Sensor arrangement (40) for mounting on a component, in particular on a tool holder or on a tool, preferably on a turning tool, with a base body (41), which has fastening means for attachment to a component and in which a receiving space (9) for a sensor module (10) is formed, which is open to an outer side of the base body (41), and a sensor module (10) according to one of claims 26 to 40, which is inserted, in particular screwed, into the receiving space (9).

62. Sensor arrangement (40) according to claim 61, further comprising a power supply unit (26) for supplying the sensor module (10) with power, wherein the power supply unit (26) is in particular accommodated in the receiving space (9), preferably arranged at an inner end of the receiving space (9).

63. Sensor arrangement (40) according to claim 61, wherein the fastening means comprise a receiving opening (42) for mounting on a component.

Description

[0041] With regard to further advantageous embodiments of the invention, reference is made to the subclaims and to the following description of an embodiment with reference to the accompanying drawing. The drawing shows

[0042] FIG. 1 a perspective view of a clamping device according to the present invention;

[0043] FIG. 2 a partial longitudinal sectional view of the clamping device from FIG. 1;

[0044] FIG. 3 the clamping device from FIG. 1 in a partial longitudinal sectional view with field lines drawn in;

[0045] FIG. 4 the clamping device from FIG. 1 in a further detailed longitudinal sectional view;

[0046] FIG. 5 the illustration from FIG. 4 with the field lines drawn in;

[0047] FIG. 6 a detailed sectional view of the base body of the clamping device from FIG. 1;

[0048] FIG. 7 a perspective view of a sensor module according to the present invention;

[0049] FIG. 8 a perspective longitudinal sectional view of the sensor module from FIG. 7;

[0050] FIG. 9 a longitudinal sectional view of the sensor module from FIG. 7;

[0051] FIG. 10 a detailed sectional view of the end area of the sensor module on the cover side shown in FIG. 7;

[0052] FIG. 11 a perspective view of the antenna of the sensor module from FIG. 7;

[0053] FIG. 12 a perspective view of a sensor arrangement according to the present invention; and

[0054] FIG. 13 a sectional view of the sensor arrangement from FIG. 11.

[0055] FIGS. 1 to 5 show a clamping device 1 designed as a chuck for fixing a tool on a machine tool according to the present invention. This comprises a base body 2 defining a clamping axis X, at the front end region of which a clamping region 3 for a tool shank is arranged. This comprises a receptacle 4 into which a tool shank of a tool to be clamped can be inserted.

[0056] In the present case, the clamping device 1 is designed as a hydraulic chuck. This means that the receptacle 4 is slightly larger than the tool shank to be clamped so that it can be inserted into the receptacle 4 with play. A thin wall 5 separates the receptacle 4 from an annular pressure chamber 6 filled with a hydraulic medium. By increasing the pressure in the pressure chamber 6, the thin wall 5 can be deformed radially inwards in order to fix a tool shank inserted in the receptacle 4 in a force-locking manner. Specifically, a clamping screw 7 is provided for this purpose, which can be moved in a hydraulic fluid supply channel (not shown) in order to increase or decrease the pressure in the pressure chamber 6.

[0057] At its rear end, the base body 2 has a machine interface 8, which is designed as a hollow shank taper (HSK) in accordance with DIN 69893.

[0058] The base body 2 also has a receiving space 9 for receiving a sensor module 10. In FIGS. 1 to 5, a sensor module 10 is inserted into the receiving space 9. In FIG. 6, the receiving space 9 is shown in detail without the sensor module inserted. The receiving space 9 is open to a circumferential surface of the base body 2 and extends radially therefrom into the base body 2. The receiving space 9, which has a circular cross-section, intersects the clamping axis X, but does not pass radially through the base body 2 completely.

[0059] A coolant channel 11 is also formed in the base body 2 in order to conduct coolant from the rear machine interface 8 to the front of the clamping area 3. The coolant channel 11 is arranged coaxially to the clamping axis X, so that the receiving space 9 intersects the coolant channel 11 and divides it into a front channel section 12 and a rear channel section 13.

[0060] The sensor module 10, which is designed as a single unit and is shown separately in FIGS. 7 to 9, comprises a tubular sensor housing 14, which defines a sensor axis Y. The sensor module 10 is screwed into the receiving space 9 of the base body 2 with the sensor housing 14. For this purpose, an internal thread 15 is formed in the outwardly open end area of the receiving space 9, which opens radially on the inside into a recess 16. Accordingly, a corresponding external thread 17 is provided in the sensor housing 14. The two threads 15, 17 are designed as metric fine threads.

[0061] In order to be able to screw the sensor module 10 into the receiving space 9, engagement means for a tool are formed on the sensor housing 14. In the present case, these comprise three recesses 18 distributed around the circumference and open outwards towards the front and radially to the sensor axis, which extend into the external thread.

[0062] Since the diameter of the receiving space 9 is larger than the diameter of the coolant channel 11, an annular coolant groove 19 is formed in the outer circumferential surface of the sensor housing 14. The width of the coolant groove 19 essentially corresponds to the diameter of the coolant channel 11. This allows coolant, which is directed to the clamping area 3, to flow from the rear channel section 13 through the coolant groove 19 past the sensor housing 14 into the front channel section 12.

[0063] In order to seal the gap between the sensor housing 14 of the sensor module 10 and the wall of the receiving chamber 9, an annular circumferential sealing groove 20, 21 is formed on both sides of the coolant groove 19. As can be seen in particular in FIG. 3, sealing rings 22 are inserted into these sealing grooves, which are pressed against the wall of the receiving chamber 9.

[0064] The receiving space 9 is stepped so as not to damage the sealing rings 22 when the sensor module 10 is inserted into the receiving space 9. This means that the area of the receiving space 9 extending from the coolant channel 11 to the open end, which is shown above the clamping axis X in FIG. 4, has a slightly larger diameter than the area which extends from the coolant channel 11 to the closed end and is arranged below the clamping axis X in FIG. 4. Accordingly, the diameter of the groove base of the sealing groove 20 is also slightly larger than the diameter of the groove base of the sealing groove 21.

[0065] The sensor module 10 also comprises a cover 23, which firmly closes the sensor housing 14 at one end. FIG. 2 shows that the cover 23 faces the outwardly open end of the housing 9. Specifically, a radially inwardly projecting annular collar 24 is provided on the closed end area of the sensor housing 14, which engages behind a corresponding annularly circumferential outer collar 25 of the closure cover 23. In this way, the closure cover 23 is held positively on the sensor housing 14.

[0066] Furthermore, the clamping device 1 comprises a power supply unit 26 to supply the sensor module 10 with power. In the present case, the energy supply unit 26, which is designed as a rechargeable battery, is housed as a separate component in the holding space. Specifically, the energy supply unit 26 is located at the inner end of the receiving space 9. A shim 27 is arranged between the energy supply unit 26 and the sensor housing 14.

[0067] In order to be able to charge the energy supply unit 26, the sensor module 10 has two externally accessible electrical charging contacts. A first electrical charging contact 28, in particular for applying a negative pole of a charger, is arranged in the closure cover 23, in this case in the center of the closure cover 23. A second electrical charging contact 29, in particular for applying a positive pole of a charger, is formed by the externally accessible annular end face of the sensor housing 14. This means that a potential difference can be applied between the sensor housing 14 and the first charging contact 28 arranged in the closure cover 23. The second charging contact 29 is electrically connected to a corresponding contact on the power supply unit 26 via the sensor housing 14 and the shim 27. In addition, there is an electrical connection between the first charging contact 28, which is arranged in the closure cover 24, and a corresponding contact of the energy supply unit 26. In this way, the energy supply unit 26 can be supplied with voltage and/or current from the outside.

[0068] The sensor module 10 also has a circuit board 30, which is arranged inside the sensor housing 14 and runs parallel to the sensor axis Y. The circuit board 30 carries a sensor element 31 for detecting operating parameters. The sensor element 31 can comprise one or more sensors, for example an acceleration sensor to detect vibrations that occur, and/or a temperature sensor and/or a motion sensor and/or a pressure sensor and/or a deformation sensor. In order to counteract influences caused by centrifugal forces, the sensor element 31 is arranged within the sensor housing 14 by selecting a suitable shim 27 in such a way that it lies on the clamping axis X or can be positioned.

[0069] The circuit board 30 also contains data processing means for processing the measurement signals provided by the sensor element 31 and is in turn connected to a data transmission device 32 for wireless transmission of measurement data recorded by the sensor element 31 to a receiver located outside the clamping device 1. In the present case, the data transmission device 32 is integrated into the closure cover 23, so that transmission to the outside is largely interference-free.

[0070] Specifically, the data transmission device 32 comprises an antenna 33 molded into the closure cover 23, which has a disk-shaped ground pole 34, which is located in the area of the annularly encircling outer collar 25 and is electrically conductively connected to the sensor housing 14, and a disk-shaped antenna pole 35, which is arranged adjacent to the outwardly facing end face of the closure cover 23. The ground pole 34 and the antenna pole 35 are each shown as dashed lines in the sectional views. As can be seen in particular in FIG. 10, the diameter of the disc-shaped grounding pole 34 is slightly larger than the diameter of the closure cover 23 at its outer end and thus also larger than the diameter of the antenna pole 35. It is preferably provided that the diameter of the grounding pole 34 is at least 80% of the diameter of the outer end region of the sealing cap, in particular at least 90%, particularly preferably at least 95%.

[0071] Both the antenna pole 35 and the earth pole 34 have a large number of honeycomb-shaped openings 36, which are filled with the plastic of which the closure cover 23 is essentially made. In this way, the earth pole 34 and the antenna pole 35 are anchored in the closure cover 23 in a particularly favorable manner, so that they can also withstand high mechanical loads due to centrifugal forces.

[0072] In order to apply a potential to the antenna pole 35, the antenna pole 35 is connected to an electrical conductor 37 which, as can be seen in FIG. 11, extends from the antenna pole 35 into the interior of the sensor housing 14 to the circuit board 30. Accordingly, the earth pole 34 has a through-opening 38 through which the electrical conductor 37 runs in the direction of the circuit board 30, electrically insulated from the earth pole 34.

[0073] A contact region 39 is formed in the center of the antenna pole 35, which is accessible from the outside, i.e. is not covered with plastic, and forms the first electrical charging contact 28.

[0074] During operation, the sensor element 31 continuously provides measurement signals. These are processed by the data processing means on the circuit board 30 and transmitted via the data transmission device 32, which is designed as an antenna 33, continuously or at specific intervals to a receiver located outside the clamping device 1, which is connected to the control system of a machine tool, for example.

[0075] The field lines of the antenna 33, which are created by a potential difference applied between the earth pole 34 and the antenna pole 35, are shown schematically in FIGS. 3 and 5, for example. For a favorable transmission of signals, it is necessary that no metallic objects are arranged in certain areas in the environment around the clamping device 1 or around the sensor module 10. These installation space limits with the basic shape of a cone K are shown in FIG. 10 by the dashed lines, between which, i.e. in the central area of FIG. 10, no metallic components should be arranged. A certain distance B should be maintained radially to the sensor axis from the antenna pole 35. This should be greater than the dimension A at which the antenna pole 35 is spaced from the end face of the sensor housing 14 on the shutter cover side. The dimension A is preferably at least 30% of the diameter of the antenna pole 35. The opening angle of the cone should be at least 10, preferably at least 20.

[0076] If the sensor module 10 according to the invention is to be replaced, it can be easily unscrewed from the receiving chamber 9. An appropriate tool is used for this purpose, which is engaged in the recesses 18. After removing the sensor module 10, the shim 27 and the energy supply unit 26 can be easily removed from the receiving space.

[0077] The clamping device 1 can be reassembled in the same way by inserting the energy supply unit 36 into the closed end of the receiving space 9. The shim 27 is then inserted before the sensor module 10 is screwed into the mounting space 9. The sensor module 10, which is designed as an assembly unit, can be replaced quickly and easily. At the same time, the energy supply device 32 can be easily charged via the cover 26. In addition, the data is transmitted via the data transmission device 32, which is housed in the sealing cover 26, with little susceptibility to interference. The sensitive components such as the sensor element 31 or the power supply unit are protected inside the housing 9 and inside the sensor housing 14.

[0078] FIGS. 12 and 13 show an embodiment of a sensor arrangement according to the invention. This comprises a base body 40, in which a receiving space 9 for a sensor module 10 is formed. This receiving space 9 is open to an outer side of the base body 40, and a sensor module 10 as described above is screwed into the receiving space 9. As with the previously described clamping device 1, the sensor arrangement 40 also comprises an energy supply unit 26, which is arranged at the inner end of the receiving space 9. A shim 27 is arranged between the energy supply unit 26 and the sensor module 10.

[0079] The sensor arrangement 40 also comprises fastening means for attaching it to a component. Specifically, these fastening means comprise a receiving opening 42, by means of which the base body 41 can be pushed onto a component. A plurality of threaded through-holes 43 are formed radially to the receiving opening 42, by means of which the base body 41 can be clamped to a component using clamping screws.

[0080] The sensor arrangement 40 according to the invention makes it possible to subsequently attach a sensor module 10 to a component, for example to a turning tool, in order to be able to reliably detect, in particular, vibrations which occur and which can be associated with increasing tool wear. In the same way as with the clamping device described above, the measurement data recorded by the sensor element 31 is processed by suitable data processing means on the circuit board 30 and transmitted externally to a receiver by means of the data transmission device 32.