SUCTION DEVICE HAVING BLADES, AND METHOD FOR THE PRODUCTION THEREOF

Abstract

The invention relates to a suction device for suctioning off wood chips and/or dust generated during the cutting machining of a workpiece, in particular for a chuck (10) for receiving a rotationally driven cutting tool (12), particularly a cutting tool for machining CFK materials or other short-chipping materials, comprising a hub portion (14) that can be rotationally driven, which supports a plurality of radial blades (16) that are evenly distributed in a circumferential direction. In each case, a blade entering edge (20) of the blade (16) extends axially away from the hub portion (14) and radially outwards to a ring portion (18) that stabilizes the blades (16) and is concentric with respect to the hub portion (14). The invention further relates to a production method for producing the suction device.

Claims

1. A suction device for suctioning off woodchips and/or dust that arises during the cutting machining of a workpiece, with a rotationally drivable hub section, which carries a plurality of radial blades that are uniformly distributed in a circumferential direction, wherein a respective blade leading edge of the blade extends axially away from the hub section and radially outward up to a ring section that is concentric to the hub section and stabilizes the blades.

2. The suction device according to claim 1, wherein an outer diameter of the hub section, the ring section, and/or the blades forms a shared enveloping cylinder, a shell surface of which surrounds the suction device.

3. The suction device according to claim 1, wherein the blades are positioned in an axial direction and/or in a radial direction.

4. The suction device according to claim 1, wherein the blades have a continuously running blade cross section over more than half the extension length of the suction device along its longitudinal axis.

5. The suction device according to claim 1, wherein the suction device is inherently integral in design.

6. The suction device according to claim 1, wherein the suction device is generatively fabricated.

7. The suction device according to claim 1, wherein the hub section is integrally designed with a clamping section of the chuck.

8. The suction device according to claim 7, wherein the clamping section forms an axially flush seal with the ring section.

9. The suction device according to claim 7, wherein the clamping section has a hydraulic clamping area or a collet chuck mechanism.

10. The suction device according to claim 3, wherein the angle of attack of the blades changes in a radial and/or axial direction over the blade extension.

11. A method for manufacturing a suction device according to claim 1, wherein the method comprises the following steps: determining a suction power required for a suction process in an area of engagement of a cutting tool with respect to speed and volume; generating a calculation model for configuring a plurality of blades of the suction device; optimizing a blade configuration in the calculation model with respect to a generated suction power; and additively fabricating the calculation model.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0039] The invention will be described below with the help of drawings. Shown on:

[0040] FIG. 1 is half a longitudinal sectional view of a suction device according to the invention, which is fastened to a shaft section,

[0041] FIG. 2 is a longitudinal sectional view of the suction device and the shaft section along line II-II,

[0042] FIG. 3 is a cross sectional view of a hub section of the suction device along line III-III depicted on FIG. 1,

[0043] FIG. 4 is a front view of the suction device,

[0044] FIG. 5 is a longitudinal sectional view of the suction device along line IV-IV depicted on FIG. 4,

[0045] FIG. 6 is a longitudinal sectional view of the suction device along line VI-VI depicted on FIG. 4,

[0046] FIG. 7 is a perspective side view of the suction device with the shaft section,

[0047] FIG. 8 is a perspective front view of the suction device,

[0048] FIG. 9 is an inclined, perspective view from in front of the suction device, and

[0049] FIG. 10 is a schematic, inclined, perspective view from above the suction device.

DESCRIPTION OF THE EXEMPLARY EMBODIMENTS

[0050] The figures are only schematic in nature, and serve exclusively for understanding the invention. The same elements are labeled with the same reference number.

[0051] FIGS. 1 to 10 show a suction device according to the invention, which is part of a chuck 10. A cutting tool 12 can be received in the chuck 10. The suction device has a rotary driven hub section 14. A plurality of radial blades or blades 16 extends from the hub section 14 in an axial direction, wherein the blades 16 are uniformly distributed in the circumferential direction of the hub section 14. The blades 16 extend from the hub section 14 up to a ring section 18 arranged coaxially, but spaced axially apart from the hub section 14. The hub section 14, the blades 16 and the ring section 18 comprise a cage-like, materially integral unit, which is also referred to as a bucket wheel.

[0052] The blades 16 each have a blade leading edge 20, which forms a radial inner edge of the blade 16 or the blade surface. The blade leading edge 20 extends axially away from the hub section 14 and radially outward, and passes over into the ring section 18. The ring section 18 thus stabilizes the blades 16. The radial distance between the longitudinal axis of the suction device and the respective blade leading edges 20 thus becomes larger with an increasing extension length from the hub section 14 to the ring section 18.

[0053] A clamping section 22 for receiving the cutting tool 12 is formed radially inside the ring section 18, and has the blades 16 arranged around it. The clamping section 22 is arranged coaxially to the ring section 18 and the hub section 14. A shaft section 24 adjoins the hub section 14 in an axial direction on a side facing away from the ring section. The hub section 14, the blades 16, the ring section 18 as well as the clamping section 22 are printed onto the shaft section 24 via 3D printing, so that they form a non-detachably interconnected unit.

[0054] The clamping section 22 has a hydraulic clamping area 26 with two pressure chambers 28. A first pressure chamber 28A is hydraulically connected with a second pressure chamber 28B axially offset relative to the first pressure chamber 28A. The pressure chambers 28 can be pressurized via a hydraulic channel 30, so that an elastically flexible partition wall deforms radially inward radially between the pressure chambers 28 and a workpiece receiving section, thereby yielding a centered clamping of the cutting tool 12 in a clamping section 22. The hydraulic channel 30 is connected with a hydraulic port in the shaft section 24 in a fluid-conducting manner. Such hydraulic chucks are known in the art, making any description of the details unnecessary.

[0055] A radial outer diameter of the clamping section 22 tapers continuously from a hub section-side end of the clamping section 22 to a ring section-side end of the clamping section 22. The clamping section 22 thus has a conical, radial outer circumferential surface. The clamping section 22 abuts axially flush with the ring section 18 at the ring section-side end of the clamping section 22, and passes over into the hub section 14 at the hub section-side end of the clamping section 22.

[0056] In an alternative embodiment, the suction device can also be designed without the clamping section 22, even if this is not shown in the drawings.

[0057] FIG. 3 shows a cross section of the hub section 14. The hub section 14 has a pre-balancing chamber 32, which has a circular cross section. The pre-balancing chamber 32 is connected with a radial outer circumference of the hub section 14 via a passage opening 34 that extends in the radial direction.

[0058] Several C-shaped or circularly shaped channels 36 are present in the hub section 14. A first channel 26A is here arranged along a first circle that is concentric to the longitudinal axis of the hub section 14. Two second channels 36B are arranged along a second circle that is concentric to the longitudinal axis of the hub section 14, and has a larger diameter than the first circle. The two second channels 36B are arranged symmetrically to a plane of symmetry that contains the longitudinal axis. Two third channels 36C are arranged along a third circle that is concentric to the longitudinal axis of the hub section 14, and has a larger diameter than the second circle. The two third channels 36C are arranged symmetrically to the plane of symmetry. The pre-balancing chamber 32 is arranged along a circle that is concentric to the longitudinal axis of the hub section 14, and has a diameter larger than that of the second circle, and smaller than that of the third circle. The second channels 36B and the third channels 36C each extend over a length of ⅛ to ¼, preferably of about ⅙, of the circumference of the second or the third circle. The first channel 36A extends over a length of ¾ of the circumference to over the entire circumference of the first circle, preferably over a length of about ⅞ of the circumference of the first circle.

[0059] As evident from FIG. 2, the channels 36 and the pre-balancing chamber 32 extend in an axial direction up to a shaft-side end of the hub section 14, as well as up to an attachment of the blades 16. The width of the channels and the pre-balancing chamber 32 here tapers as measured in the radial direction toward the blades 16.

[0060] The blades 16 or longitudinal axes of the blades 16 are inclined relative to the axial direction of the suction device along the circumferential direction. The blades or longitudinal axes of the blades 16 are also inclined relative to the radial direction of the suction device along the axial direction.

[0061] In other words, the longitudinal axes of the blades 16 each run from a hub section-side end to a ring section-side end as viewed in the radial direction, from the inside out and oriented so as to run together in the rotational direction in the circumferential direction. The blades 16 are therefore positioned both in the radial direction and in the axial direction, wherein the angle of attack changes over the blade extension.

[0062] A blade channel 38 is formed between a respective two circumferentially adjacent blades 16. The blade channels 38 each have an outlet opening, which is formed on the radial outer circumference of the bucket wheel. The outlet openings coincide with the discharge openings of the bucket wheel. The blades 16 have a triangularly shaped cross section, which is formed by the blade leading edges 20 as well as a respective two blade trailing edges 40 lying on the radial outer circumference of the bucket wheel. The blade trailing edges 40 correspond to the longitudinal edges of the discharge openings of the bucket wheel or the outlet openings of the blade channels 38.

[0063] The blade trailing edges 40 are essentially parallel to each other and positioned in an axial direction, so that a length of the blade trailing edges 40 is greater than the extension length of the blades 16 in an axial direction. The blade leading edges 20 curvedly extend in an axial direction away from the hub section 14 and radially outward, wherein the curvature increases with increasing distance from the hub section 14, i.e., the radius of curvature of the blade leading edges 20 decreases with increasing distance from the hub section (see FIGS. 5 and 6).

[0064] A continuously ring-shaped suction opening 42 is formed at the tool-side end of the bucket wheel, and is concentric to the clamping section 22. A larger suction opening here has a positive effect on the generatable suction power.

[0065] The bucket wheel is manufactured integrally with the clamping section 22 in a 3D printing process. The bucket wheel and the clamping section 22 are here fabricated from a shaft-side end, and pressed onto the shaft section 24, thereby forming a non-detachable unit comprised of the shaft section 24, the clamping section 22, and the bucket wheel. A radial outer circumferential surface of the hub section 14 passes over into a radial outer circumferential surface of the shaft section 22. This means that no ledge arises between the shaft section 24 and the bucket wheel. During production, the bucket wheel and the clamping section 22 are applied layer by layer in an axial direction. For purposes of manufacturability, a triangle-resembling section 44 is present between the transitional area between the ring section 18 and the blades 16, the outer edges of which each comprise an obtuse angle with the blades 16 and the ring section 18 (see FIGS. 7 to 10).

[0066] The suction device is used in a machine tool machining area by generating a rising flow that streams perpendicular to the longitudinal axis of the suction device. The rinsing flow is designed in such a way as to run away from the suction device in a radial direction and out of the machine tool machining area.

[0067] The structural design described above results in the following working method: While machining with the cutting tool 12 received in the chuck 10, the clamping section 22 is driven in a rotational direction around a spindle axis. Because the bucket wheel, i.e., the hub section 14, the blades 16, and the ring section 18, is integrally designed with the clamping section 22, the bucket wheel is also driven in the machining process. The configuration of the blades 16 here creates a suction flow that streams from the tool-side, continuously ring-shaped suction opening 42 of the bucket wheel through the blade channels 38 to the discharge openings on the outer circumference of the bucket wheel. This suction flow aspirates arising woodchips and dust from a workpiece surface to be machined, transporting them along with the suction flow. The woodchips and/or the dust exiting the discharge openings are then picked up by the rinsing flow in the machine tool machining area, and transported perpendicularly to the spindle axis, away from the suction device and out of the machine tool machining area.