Roll body for a hydrostatic rolling tool and hydrostatic rolling tool with the roll body

Abstract

A roll body for a hydrostatic rolling tool includes a center, an axis of rotation running through the center, and a machining zone for rolling a workpiece. The roll body is rotatable about the axis of rotation and the machining zone has a working profile line formed in a cross-section of the roll body. The working profile line has a first working arc extending around a first machining center and a second working arc extending around a second machining center. The first machining center is arranged offset to the center, and the second machining center is arranged offset to the center and offset to the first machining center. In an example embodiment, the roll body has a parallel to the axis of rotation, the first machining center lies in the cross-section on the parallel, and the second machining center lies in the cross-section on the parallel.

Claims

1.-10. (canceled)

11. A roll body for a hydrostatic rolling tool, comprising: a center; an axis of rotation running through the center; a machining zone for rolling a workpiece, wherein: the roll body is rotatable about the axis of rotation; the machining zone comprises a working profile line formed in a cross-section of the roll body; the working profile line comprises: a first working arc extending around a first machining center; and a second working arc extending around a second machining center; the first machining center is arranged offset to the center; and the second machining center is arranged offset to the center and offset to the first machining center.

12. The roll body of claim 11, further comprising a parallel to the axis of rotation, wherein: the first machining center lies on the parallel in the cross-section; and the second machining center lies on the parallel in the cross-section.

13. The roll body of claim 11, further comprising a central axis running through the center and perpendicular to the axis of rotation, wherein the central axis forms an axis of symmetry for the first working arc and the second working arc.

14. The roll body of claim 11, wherein the first working arc and the second working arc intersect in the cross-section to form a tip.

15. The roll body of claim 11, wherein: the working profile line comprises a line section comprising a first end and a second end; the first working arc opens into the first end; and the second working arc opens into the second end.

16. The roll body of claim 11 further comprising a retaining area for holding the roll body on the hydrostatic rolling tool, the retaining area comprising: a first retaining center lying on the axis of rotation; a first retaining profile line comprising a first retaining circular arc extending around the first retaining center in the cross-section; a second retaining center lying on the axis of rotation; and a second retaining profile line comprising a second retaining circular arc extending around the second retaining center in the cross-section.

17. The roll body of claim 11 further comprising a retaining area for holding the roll body on the hydrostatic rolling tool, the retaining area comprising: a first retaining profile line comprising: a first retaining circle arc or a first oval curve, the first retaining circle arc or the first oval curve comprising a first support center offset relative to the axis of rotation; and a second retaining circle arc or a second oval curve, the second retaining circle arc or the second oval curve comprising a second support center offset relative to the axis of rotation and to the first support center; and a second retaining profile line comprising: a third retaining circle arc or a third oval curve, the third retaining circle arc or the third oval curve comprising a third support center offset relative to the axis of rotation; and a fourth retaining circle arc or a fourth oval curve, the fourth retaining circle arc or the fourth oval curve comprising a fourth support center offset relative to the axis of rotation and to the third support center.

18. A hydrostatic rolling tool comprising the roll body of claim 11 arranged for rolling the workpiece.

19. The hydrostatic rolling tool of claim 18 further comprising a tool head, wherein: the tool head comprises a receptacle; and the roll body is at least partially disposed in the receptacle.

20. The hydrostatic rolling tool of claim 19, further comprising a plurality of tool heads arranged with respective roll bodies, the plurality of tool heads arranged about a circumference of the hydrostatic rolling tool or along an axis of the hydrostatic rolling tool such that passive forces from rolling a workpiece are canceled out.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Further characteristics, advantages and effects of the disclosure are set out in the following description of example embodiments. In the figures:

[0032] FIG. 1 shows a hydrostatic rolling tool with a base body and with two tool heads, on each of which a roll body is arranged;

[0033] FIG. 2 shows the rolling tool shown in FIG. 1, with the rolling bodies arranged differently on the base body;

[0034] FIG. 3a shows a roll body with a machining zone in a first embodiment;

[0035] FIG. 3b shows a machining zone of the roll body in a second version;

[0036] FIGS. 4, 5 show the roll body from FIG. 3a with differently designed retaining areas;

[0037] FIG. 6a shows a tool head of the rolling tool with a receptacle in which the roll body shown in FIG. 4 is accommodated;

[0038] FIG. 6b shows a tool head of the rolling tool with a receptacle in which the roll body shown in FIG. 5 is accommodated;

[0039] FIG. 7 shows a modified tool head with two centering devices that protrude into the holder.

DETAILED DESCRIPTION

[0040] Parts that correspond to each other or are identical are marked with the same reference marks in the illustrations.

[0041] FIG. 1 shows a longitudinal section through a hydrostatic rolling tool 10. Rolling tool 10 can be coupled and operated with a suitable machine tool, e.g., a lathe, especially a CNC machine. The rolling tool 10 includes an elongated circular cylindrical body 11 and two tool heads 12, 13. A roll body 1 is arranged on each tool head 12, 13. When operating the rolling tool 10, the roll body 1 is designed to roll a workpiece that is not shown. Rolling refers to soft or hard working, with which a wide variety of contour shapes, e.g., holes, radii, internal threads, recesses, ellipses and/or contours with several offset radii can be introduced into the workpiece. The holes to be drilled with roll body 1 may have a relatively small diameter of 10 millimeters, 15 millimeters or 20 millimeters, for example. Even larger components, e.g. shafts, can be machined with the rolling tool.

[0042] The two tool heads 12, 13 are arranged 180 degrees offset to each other in the circumferential direction of the base body 11. In a further design example according to FIG. 2, the tool heads 12, 13 can additionally be arranged axially offset to each other, e.g., along a longitudinal axis A of the base body 11. Alternatively the rolling tool 10 can have only one tool head 12 or more than two tool heads 12, 13.

[0043] FIG. 3a shows a cross-section of the roll body 1. The roll body 1 is spherical, for example in the form of a profiled ball, the outer contour of which deviates from a ball K shown for comparison, but is essentially oriented to the outer contour of the ball K The roll body 1 has a center Z and a central axis L similar to the ball K. It can be rotated about an axis of rotation R during operation of rolling tool 10. The axis of rotation R runs through the center Z and extends at right angles to the central axis L.

[0044] The roll body 1 has a machining zone 2 and a retaining area 8. In the retaining area 8 the roll body 1 is held by the tool head 12, as shown in FIGS. 6a, 6b and 7. The machining zone 2 is shown in FIG. 3a in a first possible configuration and in FIG. 3b in a second possible configuration. The machining zone 2 is the area that touches the workpiece and is rolled during operation of rolling tool 10 (FIGS. 1, 2). The desired contour is worked into the workpiece in machining zone 2.

[0045] A maximum diameter D of the roll body 1 in the machining zone, measured along the center line L may be 20 millimeters, 10 millimeters, or 2 millimeters, for example.

[0046] The machining zone 2 has a working profile line 3 in cross section. The working profile line 3 includes a first working arc 4a and a second working arc 4b.

[0047] The first working arc 4a extends around a first working center point M4a and the second working arc 4b extends around a second working center M4b. The working centers M4a, M4b are located on a parallel P to the rotation axis R, offset to each other, to the central axis L and to the center Z. The radii R4a and R4b of the two working arcs 4a, 4b are of the same size, so that the working arcs 4a, 4b are symmetrical to each other, with the central axis L forming an axis of symmetry for this purpose. Due to this design and arrangement of the working arcs 4a, 4b, the two intersect at a point 5, which is located on the central axis L.

[0048] As shown in FIG. 3b in a cross-sectional view of the machining zone, the tip 5 can be eroded and/or flattened so that the working profile line 3 has a line segment 6 in the cross-section of the roll body 1. In this way, a free area 7 can be created by line segment 6, which interrupts and/or divides machining zone 2. This means that the free area 7 is not used for working the workpiece, e.g., the free area 7 is arranged without contact with the workpiece during and/or during the rolling of the workpiece. This ensures, for example, that the desired contours are brought into the workpiece.

[0049] The line segment 6 is designed as a line that extends between the first working arc 4a and the second working arc 4b and connects the two working arcs 4a, 4b with each other. For example, the first working arc 4a ends in a first end E1 of line segment 6 and the second working arc 4b in a second end E2 of line segment 6. The line segment 6 runs parallel to the rotation axis R (FIG. 3a). In an alternative embodiment, line segment 6 can also be curved and/or bent.

[0050] As shown in FIGS. 4 and 5 in a cross-sectional view of roll body 1, roll body 1 has a retaining area 8. In the retaining area 8 the roll body 1 can be held on the rolling tool 10 as shown in FIGS. 6a, 6b and 7.

[0051] The retaining area 8 has a first retaining profile line 9a, which is formed in the cross-section of the roll body 1, and a second retaining profile line 9b, which is formed in the cross-section of the roll body 1. The retaining profile lines 9a, 9b are symmetrical to each other, with the central axis L forming the axis of symmetry for this purpose. The two retaining profile lines 9a, 9b end in two mouthpiece areas 16a, 16b, which are designed as radii.

[0052] As shown in FIG. 4, the first retaining profile line 9a forms a first retaining circle arc which extends around a first support point M9a located on the axis of rotation R. The second retaining profile line 9b forms a second retaining circle arc, which extends around a second retaining center M9b lying on the axis of rotation R.

[0053] As shown in FIG. 5, each of the two retaining profile lines 9a, 9b may include a first oval curve and a second oval curve 14a, 14b, which intersect at other tips 15a, 15b. The other tips 15a, 15b are arranged on the rotation axis R. In an example embodiment (not shown), each of the two retaining profile lines 9a, 9b has two retaining circle arcs instead of the oval curves 14a, 14b, the centers of which are offset to each other and to the axis of rotation R.

[0054] FIGS. 6a and 6b show a first tool head 12 of tool heads 12, 13 of rolling tool 10 from FIG. 1 or 2. The tool head 12 has a receptacle 17, which forms a cage for the roll body 1.

[0055] According to FIG. 6a, the roll body 1 from FIG. 4 is at least partially contained in receptacle 17. According to FIG. 6b, the roll body 1 from FIG. 5 is included in receptacle 17. The roll body 1 is held at the retaining area 8 in the receptacle 17.

[0056] The receptacle 17 forms a negative mold for the shape and/or contour of the roll body 1 to be arranged in it. The respective rolling bodies 1 are rotatably mounted in the receptacle 17. To this end, the receptacle 17 is slightly more voluminous than the roll body 1.

[0057] The rolling tool 10 (see FIGS. 1, 2) has a feed channel 18 which runs through the tool head 12, 13 and ends in the receptacle 17. A pressure and fluid source (not shown) can be assigned to the rolling tool 10, with which a pressurized fluid can be fed through the feed channel 18 into the receptacle 17. This allows the roll body 1 in the receptacle 17 to be hydrostatically loaded with force and rotated about the rotation axis R. A relief channel 19 is provided in the tool head 12, from which excess fluid can escape from the receptacle 17.

[0058] As shown in FIG. 7, two centering devices 20a, 20b can be provided in the tool head 12 for pre-positioning the roll body 1. The two centering devices 20a, 20b protrude into the receptacle 17 and are arranged opposite each other at the same height. They lie on the axis of rotation R and engage in the retaining area 8 at the holding profile lines 9a, 9b of the roll body 1.

REFERENCE NUMERALS

[0059] 1 Rolling bodies

[0060] 2 Machining zone

[0061] 3 Working profile line

[0062] 4a,b Working arcs

[0063] 5 Tip

[0064] 6 Line segment

[0065] 7 Free area

[0066] 8 Retaining area

[0067] 9a,b Retaining circle arcs

[0068] 10 Rolling tool

[0069] 11 Base body

[0070] 12 First tool head

[0071] 13 Second tool head

[0072] 14a,b Oval curves

[0073] 15a,b Other tips

[0074] 16a,b Mouthpiece areas

[0075] 17 Receptacle

[0076] 18 Supply channel

[0077] 19 Bypass channel

[0078] 20a,b Centering devices

[0079] L Central axis

[0080] M4a Center of the first machining arc

[0081] M4b Center of the second machining arc

[0082] P Parallel

[0083] R4a Radius of the first machining arc

[0084] R4b Radius of the second machining arc

[0085] Z Center