Abstract
The invention relates to a method for producing at least one gear, in particular a helically toothed gear, wherein the gear is produced from a gear blank pressed and sintered with an oversize in the region of the set of teeth, wherein the gear blank has two opposite end faces and a circumference. In the method, the gear blank is clamped in a clamping means. The gear blank is compressed in the region of the oversize by means of the engagement of at least one circumferential tool having a set of mating teeth that engages with the set of teeth of the gear blank, wherein the gear blank is radially clamped over the circumference by the clamping means at both end faces during the compression of the gear blank, wherein each individual tooth of the set of teeth of the gear blank is supported by the clamping means substantially over the entire tooth height. In this way, the quality of the set of teeth can be improved. The invention further relates to a device and to a clamping means.
Claims
1. A method for producing a gear wheel, in particular a helical gear wheel, wherein the gear wheel is produced from a gear-wheel blank which is sintered and in which a toothing is pressed so as to be oversized, wherein the gear-wheel blank has two mutually opposite end sides and one circumference, the method comprising the following method steps: clamping the gear-wheel blank in a clamp, compressing the gear-wheel blank in the toothing by engaging at least one revolving tool having a counter-toothing which engages in the toothing of the gear-wheel blank, wherein the gear-wheel blank during compression thereof at both end sides is radially clamped across the circumference by the clamp, wherein each individual tooth of the toothing of the gear-wheel blank is supported by the clamp substantially across an entire tooth height; wherein the clamp has a toothing geometry which is identical to that of the gear-wheel blank.
2. The method as claimed in claim 1, wherein the gear-wheel blank is axially jammed.
3. The method as claimed in claim 1, wherein at least two gear-wheel blanks are clamped in the clamp, in order for at least two gear wheels to be produced.
4. The method as claimed in claim 3, wherein an engagement of the at least one revolving tool in the toothing of the at least two gear-wheel blanks is performed simultaneously or successively.
5. The method as claimed in claim 1, wherein the toothing geometry of the clamp has an equidistant undersize in which the toothing geometry of the clamp tapers off in an axial direction.
Description
(1) In the figures:
(2) FIG. 1 shows a rolling assembly;
(3) FIG. 2 shows a further rolling assembly;
(4) FIG. 3 shows a sectional view of a device in which a gear-wheel blank having a protruding step is clamped in a clamping means;
(5) FIG. 4 shows a sectional view of a device in which a gear-wheel blank without a protruding step is clamped in a clamping means;
(6) FIG. 5a shows a sectional view of a device in which a gear-wheel blank is clamped in a clamping means, wherein the gear-wheel blank has an elevation and the clamping means has a depression;
(7) FIG. 5b shows a detailed view of the detail A of FIG. 5a,
(8) FIG. 5c shows a view of the end side of a tooth of the gear-wheel blank of FIGS. 5a and 5b;
(9) FIG. 6a shows a further sectional view of a device in which a gear-wheel blank is clamped in a clamping means, wherein the gear-wheel blank has an elevation and the clamping means has a depression;
(10) FIG. 6b shows a detailed view of the detail B of FIG. 6a,
(11) FIG. 6c shows a view of the end side of a tooth of the gear-wheel blank of FIGS. 5a and 5b;
(12) FIG. 7a shows a device having a clamping means, wherein a plurality of gear-wheel blanks are clamped so as to be spaced apart by means of clamping elements;
(13) FIG. 7b shows a further device having a clamping means, in which a plurality of gear-wheel blanks are clamped so as to be spaced apart by means of clamping elements;
(14) FIG. 7c shows a third device having a clamping means, in which a plurality of gear-wheel blanks are clamped so as to be spaced apart by means of clamping elements; and
(15) FIG. 8 shows a device having a clamping means, in which a plurality of gear-wheel blanks are clamped so as to be directly adjacent to one another;
(16) FIG. 9 shows a schematic view of a gear wheel.
(17) FIG. 1 shows an exemplary rolling assembly in a schematic view. A first rolling tool 10 having a first toothing 12 is mounted so as to be rotatable in the rotation direction 16 about a first axis 14. The rotation direction may be varied once or even multiple times during rolling. Also, a first rotation orientation may point in a direction which is counter to the direction illustrated. The first toothing 12 is engaged in a second toothing 18 of a gear-wheel blank 20. The gear-wheel blank 20 is mounted so as to be rotatable about a second axis 22. A second rotation direction 24 results accordingly. Furthermore, the second toothing 18 is engaged in a third toothing 26 of a second tool 28. This second tool 28 is mounted so as to be rotatable in a third rotation direction 32 about a third axis 30. By way of this rolling assembly, compression of the gear-wheel blank 20 in the region of oversizing on the may be performed for example by engagement at least of the revolving tools 10 and 28 in a counter-toothing 12 and 26, which engages in the toothing 18 of the gear-wheel blank 20.
(18) FIG. 2 shows a schematic view of a further possibility as to how at least two gear-wheel blanks 20 may be simultaneously compressed, for example. Apart from the movement of the tool 34, movement of the gear-wheel blanks 20 in the direction of the tool 34 may also be performed. Moreover, there is the potential for two or a plurality of gear-wheel blanks 20 to be disposed on one gear-wheel blank axis.
(19) FIG. 3 shows a sectional view of a device 36 in which a gear-wheel blank 38 having a protruding step 40 is clamped in a clamping means 42. The clamping means 42 comprises two thrust collars 44 and 46, the gear-wheel blank 38 being jammed therebetween. It is illustrated that the thrust collars 44 and 46 support each individual tooth of the toothing of the gear-wheel blank 38 between the thrust collars 44 and 46 substantially across the entire tooth height. Herein, the clamping means 42 with the aid of the thrust collars 44 and 46 for radial clamping axially jams the gear-wheel blank 38, on account of which the rigidity of the end-side tooth ends of the gear-wheel blank 38 is increased and, on account thereof, the elastic deformation is reduced. The clamping means 42 has a toothing geometry which is identical to that of the gear-wheel blank 38 and which for compensation of elastic influences in the axial direction has an equidistant undersize. In order for collisions to be avoided in the case of an adjustment of the tools which is optimized for the flank-line angles, the toothing geometry of the clamping means 42 tapers off in the axial direction. The toothing geometry thus produced in terms of the basic concept corresponds to a beveloid toothing.
(20) The thrust collar 46 has an annular shoulder 48 which supports the step 40 in a form-fitting manner. The step 40 here may be configured so as to be cylindrical and together with the annular shoulder 48 configure a plug-fit toothing connection.
(21) FIG. 4 shows a device 36 in which a gear-wheel blank 50 is clamped in the clamping element 42. As opposed to FIG. 3, the gear-wheel blank 50 has no step 40.
(22) FIGS. 5a, 5b, 5c show a device 36 in which a gear-wheel blank 52 is clamped in a clamping means 42. The detail A of FIG. 5a is illustrated in an enlarged manner in FIG. 5b. In FIG. 5b it is illustrated that a tooth 54 of the gear-wheel blank 52, at the end side thereof that is directly adjacent to the clamping means 42, has an elevation 56. The elevation 56 engages in a depression 58 of a clamping-means tooth 60. Reproducible positioning of the gear-wheel blank 52 and of the clamping means 42 may be guaranteed by way of an engagement of the elevation 56 in the depression 58. It is illustrated in FIG. 5c that the elevation 56 has a round shape.
(23) FIGS. 6a, 6b, 6c show another embodiment of the device 36, in which a gear-wheel blank 62 is clamped in a clamping means 42. An enlargement of the detail B of FIG. 6a is illustrated in FIG. 6b. Like FIG. 5b, FIG. 6b shows that a tooth 64 of the gear-wheel blank 62, at the end side thereof which is directly adjacent to the clamping means 42, has an elevation 66. The elevation 66 engages in a depression 68 of a clamping-means tooth 70. Reproducible positioning of the workpiece and of the clamping means may be guaranteed by way of an engagement of the elevation 66 in the depression 68. It is illustrated in FIG. 6c that the elevation 66 has an oval shape.
(24) FIG. 7a shows a device 36 in which a plurality of gear-wheel blanks 72 in axial sequence are clamped in a clamping means 42. Those respective end sides of the gear-wheel blanks 72 that are not disposed so as to be directly adjacent to the thrust collars 44, 46 of the clamping means 42 are disposed on clamping elements 74. The clamping elements 74 in FIG. 7a are of dissimilar widths. It is furthermore illustrated in FIG. 7a that the thrust collars 44, 46 of the clamping means 42 clamp the gear-wheel blanks 72 and the clamping elements 74 with the aid of nuts 76 and 78, for example. However, other bracing components which enable bracing of gear-wheel blanks 72 and of thrust collars 44, 46 may also be employed instead of nuts. The clamping elements 74 have a toothing geometry which is identical to that of the gear-wheel blanks 72. Furthermore, the clamping elements 74 on the end side may have at least one annular shoulder, depression, or elevation, so as to configure together with the gear-wheel blanks 72 reproducible positioning of gear-wheel blanks 72 and of the respective clamping elements 74.
(25) FIG. 7b shows a further embodiment of a device 36, in which a plurality of gear-wheel blanks 80 and 82 are clamped in a clamping means 42. Those respective end sides of the gear-wheel blanks 80, 82 that are not disposed so as to be directly adjacent to the thrust collars 44, 46 of the clamping means 42 are disposed on clamping elements 74. The clamped gear-wheel blanks 80 and 82 in this exemplary embodiment are of dissimilar widths. However, said gear-wheel blanks may also be of identical width and size. The thrust collars 44, 46 of the clamping element 42 in this exemplary embodiment clamp the clamping elements 74 and the gear-wheel blanks 80, 82 without the aid of nuts 76, 78.
(26) FIG. 7c shows a third embodiment of a device 36, in which a plurality of gear-wheel blanks 72 are clamped in a clamping means 42. Like in FIG. 7a, clamping elements 74 are disposed between those respective end sides of the gear-wheel blanks 72 that are not disposed so as to be directly adjacent to the thrust collars 44, 46 of the clamping means 42. The gear-wheel blanks 72 are of identical width, and the thrust collars 44, 46 of the clamping element 42 in this exemplary embodiment clamp the clamping elements 74 and the gear-wheel blanks 72 without the aid of nuts 76, 78.
(27) FIG. 8 shows a further embodiment of a device 36, in which two gear-wheel blanks 84 are disposed between the thrust collars 44, 46 of the clamping means 42. Those respective end sides of the gear-wheel blanks 84 that are not disposed so as to be directly adjacent to the thrust collars 44, 46 of the clamping means 42 are disposed next to one another.
(28) FIG. 9 shows a schematic side view of a gear wheel 86. Once the gear-wheel blank has been compressed, a step 88 may be incorporated thereinto by means of machining, if required. Machining may include milling, grinding, and/or turning, for example.
