Multi-component gear, gear and planetary gearset

Abstract

The present invention relates to a multi-component gear (1) with an axis of rotation (X) and a first end face (11) and a second end face (12), having an inner part (20) and an outer part (30) made of a plastic with at least one injection-molding section (32), wherein the outer part (30) is arranged on an outer lateral surface (24) of the inner part (20) in a form-fitting and/or integral manner on the inner part (20), and wherein the outer part (30) on the first and/or the second end face (11, 12) has at least one tab (40) which is free-standing in the circumferential direction around the axis of rotation (X) and which protrudes over the relevant end face (11, 12) of the inner part (20). The present invention also relates to a gear (2) and a planetary gearset (3).

Claims

1. A multi-component gear (1) with an axis of rotation (X) and a first end face (11) and a second end face (12), comprising: an inner part (20), and an outer part (30) made of a plastic with at least one injection-molding section (32), wherein the outer part (30) is arranged on an outer lateral surface (24) of the inner part (20) in a form-fitting and/or integral manner on the inner part (20), and wherein the outer part (30) on the first and/or the second end face (11, 12) has at least one tab (40) which is free-standing in the circumferential direction around the axis of rotation (X) and which protrudes over the relevant end face (11, 12) of the inner part characterized in that the at least one tab (40) protrudes from a recess (46) (20).

2. The multi-component gear (1) according to claim 1, characterized in that the outer part (30) has a toothed ring (35).

3. The multi-component gear (1) according to claim 1, characterized in that the tabs (40) are arranged symmetrically around the circumference.

4. The multi-component gear (1) according to claim 1, characterized in that the number of tabs (40) on the first and the second end face (11, 12) is the same.

5. The multi-component gear (1) according to claim 1, characterized in that the tabs (40) protrude from a flange (36) set back from the first and/or the second end face (11, 12).

6. The multi-component gear (1) according claim 1, characterized in that the at least one tab (40) is formed by a free-standing L-shaped tongue (41).

7. The multi-component gear (1) according to claim 1, characterized in that the at least one tab (40) has a cut-out (48).

8. The multi-component gear (1) according to claim 1, characterized in that at least one pocket (50) connecting the first end face (11) and the inner lateral surface of the outer part (30) and/or at least one pocket (50) connecting the second end face (12) and the inner lateral surface (34) of the outer part (30) is provided.

9. The multi-component gear (1) according to claim 8, characterized in that the at least one pocket (50) exposes the outer lateral surface (24) of the inner part (20) in some areas.

10. The multi-component gear (1) according to claim 8, characterized in that the number of tabs (40) on the first end face (11) and on the second end face (12) is the same and/or that the number of pockets (50) on the first end face (11) and on the second end face (12) is the same.

11. The multi-component gear (1) according to claim 8, characterized in that the at least one tab (40) on the first end face (11) and the at least one tab (40) on the second end face (12) are arranged in alignment with one another in the circumferential direction in the direction of the axis of rotation (X).

12. The multi-component gear (1) according to claim 9, characterized in that the at least one pocket (50) on the first end face (11) and/or the second end face (12) is aligned with the at least one tab (40) on the other end face (11, 12) in the circumferential direction in the direction of the axis of rotation (X).

13. The multi-component gear (1) according to claim 1, characterized in that the outer part (30) on the first and/or the second end face (11, 12) has two or more tabs (40) that are free-standing in the circumferential direction, and that between two adjacent tabs (40) a free area (45) is formed.

14. The multi-component gear (1) according to claim 1, characterized in that the at least one pocket (50) is arranged in the circumferential direction in the free area (45) and/or that the at least one pocket (50) is arranged over the entire free area (45).

15. A multi-component gear (1) with an axis of rotation (X) and a first end face (11) and a second end face (12), comprising: —an inner part (20), and —an outer part (30) made of a plastic with at least one injection-molding section (32), —wherein the outer part (30) is arranged on an outer lateral surface (24) of the inner part (20) in a form-fitting and/or integral manner on the inner part (20), and —wherein the outer part (30) on the first and/or the second end face (11. 12) has at least one tab (40) which is free-standing in the circumferential direction around the axis of rotation (X) and which protrudes over the relevant end face (11, 12) of the inner part (20), wherein. at least one weld line (33) is formed and that the at least one tab (40) is arranged in the circumferential direction at a distance from the at least one weld line (33).

16. The multi-component gear (1) according to claim 1, characterized in that the inner part (20) is a shaft or a roller bearing with an inner ring (21) and an outer ring (22).

17. The multi-component gear (1) according to claim 1, characterized in that the at least one tab (40) of the outer part (30) protrudes by at least 0.5 mm in a radial direction onto the first end face (11) and/or the second end face (12) of the outer ring (22), but does not protrude beyond the outer ring (22) in the radial direction.

18. A gear (2), in particular a planet gear, formed from a multi-component gear (1) according to claim 1.

19. A planetary gearset (3) having at least one gear (2) with the features of claim 18.

Description

(1) Seven exemplary embodiments of a multi-component gear according to the invention are described below with reference to the accompanying drawings. In the drawings:

(2) FIG. 1 is a perspective view of a planet carrier of a planetary gearset with four planet gears designed as a multi-component gear;

(3) FIG. 2 is a front view of a multi-component gear according to FIG. 1;

(4) FIG. 3 is a sectional view of the multi-component gear according to the section line B-B in FIG. 2;

(5) FIG. 4 shows a detailed illustration of the sectional illustration according to FIG. 3;

(6) FIG. 5 is a front view of a second embodiment of a multi-component gear;

(7) FIG. 6 shows a sectional view of the multi-component gear according to the section line A-A in FIG. 5,

(8) FIG. 7 is a front view of a third embodiment of the multi-component gear;

(9) FIG. 8 shows a sectional view of the multi-component gear according to the section line C-C in FIG. 7;

(10) FIG. 9 is a perspective view of a fourth embodiment of the outer part of the multi-component gear according to FIG. 1;

(11) FIG. 10 is a front view of the outer part according to FIG. 9;

(12) FIG. 11 shows a sectional illustration along the section line A-A according to FIG. 10;

(13) FIG. 12 shows a sectional illustration along the section line B-B according to FIG. 10;

(14) FIG. 13 shows a sectional illustration along the section line C-C according to FIG. 10;

(15) FIG. 14 shows a sectional illustration along the section line D-D according to FIG. 10;

(16) FIG. 15 is a perspective view of a fifth embodiment of the outer part of the multi-component gear according to FIG. 1;

(17) FIG. 16 is a front view of the outer part according to FIG. 15;

(18) FIG. 17 shows a sectional illustration along the section line C-C according to FIG. 16;

(19) FIG. 18 shows a sectional illustration along the section line D-D according to FIG. 16;

(20) FIG. 19 shows a sectional illustration along the section line E-E according to FIG. 16,

(21) FIG. 20 shows a perspective illustration of a sixth exemplary embodiment, the tab having a cut-out;

(22) FIG. 21 shows a detailed representation of the tab according to FIG. 20;

(23) FIG. 22 shows a perspective illustration of a seventh exemplary embodiment, and

(24) FIG. 23 shows a detailed representation according to FIG. 22.

(25) Identical or functionally identical components are identified below with the same reference symbols. For the sake of clarity, not all identical or functionally identical parts are provided with a reference number in the individual figures.

(26) FIG. 1 shows a planet carrier 4 of a planetary gearset 3, which is not shown in full, having four multi-component gears 1, which are designed as planet gears 2 with a toothed ring 35.

(27) A first exemplary embodiment of the multi-component gear 1 is shown in FIGS. 2 to 4 and it can be seen that the multi-component gear 1 comprises an inner part 20 and an outer part 30. The multi-component gear 1 has an axis of rotation X which approximately forms an axis of symmetry of the multi-component gear 1 and with which the inner part 20 and the outer part 30 are arranged coaxially.

(28) The multi-component gear 1 can be cylindrical or hollow-cylindrical and can furthermore form a hub on an inner lateral surface 13. The multi-component gear 1 has a first end face 11 and a second end face 12, which are arranged parallel in the axis of rotation X and spaced apart on two diametrical sides.

(29) The inner part 20 is circular with a width B.sub.2 and can be made of any material. In the exemplary embodiment shown, the inner part 20 is a conventional ball bearing with an inner ring 21, an outer ring 22, several rolling elements 26 and two sealing disks 27. The inner part 20 has an inner diameter D.sub.13, in which an inner lateral surface 13 lies, and an outer diameter D.sub.24, on which an outer lateral surface 24 is arranged as a cylinder lateral surface. The outer lateral surface 24 is preferably a turned or ground surface and preferably has an average roughness value of Ra≤32 μm.

(30) The outer part 30 is preferably sprayed onto the inner part 20 in an injection molding process, the inner part 20 being overmolded as an insert. As a result of the method, the outer part 30 thus has at least one injection-molding section 32, which is preferably formed on at least one of the end faces 11, 12. The outer part 30 is preferably made of a plastic and, during the overmolding, is arranged both on the outer lateral surface 24 of the inner part 20 and—as will be explained below—on the end faces 11, 12.

(31) The outer part 30 is substantially ring-shaped with a width B3 and is aligned coaxially with the inner part 20. The outer part 30 of the multi-component gear 1 can—as shown in the exemplary embodiments according to FIGS. 1 to 8—have the toothed ring 35 with any tooth shape. The width B3 of the outer part 30 is greater than the width B2 of the inner part 20.

(32) On the first end face 11 and on the second end face 12, the outer part 30 has in each case six tabs 40, which are free-standing in a circumferential direction around the axis of rotation X and protrude radially inward in the direction of the axis of rotation X and in some areas onto the end faces of the inner part 20 to form a axial lock.

(33) The tabs 40 are formed together with the outer part 30 during injection molding, whereby the tabs 40 and the outer part 30 are formed from a single piece.

(34) According to a further development (not shown), the width B3 of the outer part 30 can also be smaller or greater than the width B2 of the inner part 20 or can also have the same dimensions. In this development, the tabs 40 can project beyond the first end face 11 and/or the second end face 12 in the direction of the axis of rotation X.

(35) As can be seen in particular from FIG. 4, the tabs 40 project radially inward, starting from the inner diameter D.sub.34 of the outer part 30 or the outer diameter D.sub.24 of the inner part 20. Furthermore, it can be seen from FIGS. 3 and 4 that the tabs 40 on the first end face 11 and the second end face 12 are in alignment with the end faces of the outer part 30. The tabs 40 rest on the particular end face 11, 12 of the inner part 20.

(36) In the radial direction, each tab 40 ends in a diameter D.sub.40, which is smaller than the outer diameter D.sub.24 of the inner part 20 and is greater than the inner diameter D.sub.13 of the inner part. The diameter D.sub.40 is preferably at least 1 mm smaller than the outer diameter D.sub.24 of the inner part 20.

(37) It can also be seen from FIG. 4 that the diameter D.sub.40 is selected in such a way that the tabs 40 do not extend as far as the sealing disk 27 in order to prevent plastic from penetrating the roller bearing cage during the manufacturing process. Correspondingly, the diameter D.sub.40 is at least as large as an outer diameter D.sub.27 of the sealing disk 27, the diameter D.sub.40 preferably being selected by an oversize of about 1 mm or greater than the outer diameter D.sub.27 of the sealing disk 27 in order to enable suitable sealing measures for the rolling element during injection molding.

(38) Between the tabs 40 on the first end face 11 and the second end face 12 a free area 45 is formed in each case, through which the free-standing tabs 40 are interrupted in the circumferential direction around the axis of rotation X. The free area 45 extends in the circumferential direction with a diameter D.sub.45 which is at least as large as the outer diameter D.sub.24 of the outer lateral surface 24 of the inner part 20, that is, D.sub.45≥D.sub.24. In the circumferential direction, a transition area 42 is formed between the free area 45 and the tab 40, which is formed by several transition radii 43 to avoid sharp-edged transitions.

(39) The tabs 40 extend in the circumferential direction by a radian measure of preferably approximately 30°, wherein the radian measure can be selected as desired.

(40) The sectional views according to FIGS. 3 and 4 also show that the outer part 30 has a plurality of pockets 50 which are arranged in the circumferential direction both on the first end face 11 and on the second end face 12 between the tabs 40.

(41) The pockets 50 extend in regions both over the relevant end face 11, 12 and over the inner lateral surface 34 of the outer part 30. For this purpose, the pockets 50 extend radially outward from the axis of rotation X up to a diameter D.sub.50, which is greater than the inner diameter D.sub.34 of the inner part 20. Each pocket 50 connects one end face 11, 12 to the inner lateral surface 34. In addition, it can be seen from FIG. 4 that the pockets 50 expose the outer lateral surface 24 of the inner part 20 in some areas, whereby the plastic wall thickness of the outer part 30 is reduced in the circumferential direction and thus counteracts possible cavity formation.

(42) In relation to the width B2 (see FIG. 4), the pockets 50 expose at least 1 mm of the outer lateral surface 24 of the inner part 20, the pockets 50 preferably exposing the outer lateral surface 24 of the inner part 20 by a width B4, which is determined as follows: B4≈(B3−B2)/2. However, the maximum width B4 of each pocket 50 measured parallel to the axis of rotation X should not be more than 0.4*B2, that is to say, 40% of the width B2.

(43) As shown in the illustrated embodiment, the pocket 50 can extend over the entire free area 45 in the circumferential direction. The diameter D50 of the pocket 50 and the diameter D45 of the free area can also have the same dimensions.

(44) As can also be seen from FIGS. 3 and 4, the tabs 40 and the pockets 50 on the first end face 11 and the second end face 12 are offset from one another in such a way that, in the direction of the axis of rotation X, the tabs 40 on the first end face 11 are arranged in alignment with the pockets 50 on the second end face 12 (in each case based on their center point in the circumferential direction) and vice versa. This arrangement of the tabs 40 and pockets 50 offset in the circumferential direction makes it possible to reduce length shrinkage, as a result of which any residual stresses in the outer part 30 can be reduced.

(45) A second exemplary embodiment is shown in FIGS. 5 and 6, the difference between the first exemplary embodiment and the second exemplary embodiment being that a different number of tabs 40 is provided.

(46) FIG. 5 shows that three free-standing tabs 40 are arranged in the circumferential direction on the first end face 11, but also on the second end face 12. The three free-standing tabs 40 extend in the circumferential direction by a radian measure of approximately 30° and are arranged symmetrically at an angular division of 120°. The free area 45 between the tabs 40 is completely taken up by the pockets 50, as a result of which the pockets 50 extend in the circumferential direction by a radian measure of approx. 60° around the axis of rotation X.

(47) As can be seen in particular from FIG. 6, analogously to the first exemplary embodiment, the tabs 40 on the first end face 11 and the pockets 50 on the second end face 12 and vice versa (each based on the center point in the circumferential direction) are arranged in alignment with one another in the direction of the axis of rotation X. The above-mentioned radian measures for the tabs 40 and the free area 45 can be varied as desired.

(48) The exemplary embodiment shown in FIGS. 7 and 8 differs from the exemplary embodiments presented above in that the tabs 40 on the first end face and the tabs 40 on the second end face 12 (based on the center point in the circumferential direction) are aligned with one another.

(49) The fourth exemplary embodiment is shown in FIGS. 9-14. The outer part 30 is produced from a plastic, preferably by injection molding, and can—as shown—have three injection-molding sections 32 distributed symmetrically around the axis of rotation X in the circumferential direction. During the manufacturing process, liquefied plastic is introduced into a corresponding cavity (not shown) of a mold (not shown), the injection-molding sections 32 being formed where the plastic is injected into the cavity of the mold. The liquefied plastic is distributed in the cavity, the flow fronts meeting in the circumferential direction approximately between the injection-molding sections 32 and a so-called weld line 33, in which the flow fronts are welded. The position of the injection-molding sections 32 and of the weld line 33 can be seen in FIG. 10, the weld lines 33 being shown by means of a dash-dotted line for better understanding.

(50) The outer part 30 has a flange 36 set back from the first end face 11 and the second end face 12, the free end of which points to the axis of rotation X. In particular, FIG. 13 shows that the set-back flange 36 extends from a first outer edge 38a to a first inner edge 37a on the side facing the first end face 11 and from a second outer edge 38b to a second inner edge 37b on the side facing the second end face 12. The distance between the first outer edge 38a and the second outer edge 38b is greater than the distance between the first inner edge 37a and the second inner edge 37b.

(51) The set-back flange 36 can have a tapering shape, wherein the set-back flange 36 can be designed to be increasingly tapered with a decreasing radius—in relation to the axis of rotation X. The tapering shape of the flange can be seen in FIG. 13. The free end of the set-back flange 36 forms the inner lateral surface 34, which can be in contact with the inner part 20.

(52) A plurality of L-shaped tongues 41, which have a first section and a second section, protrude from the set-back flange 36. The first section is arranged approximately parallel to the axis of rotation X, while the second section is angled perpendicular to the first section and forms a tab 40, which is set up to protrude over the relevant end face 11, 12 of the inner part 20. As can be seen in particular from FIGS. 10 and 11, three L-shaped tongues 41 are arranged on each end face 11, 12, which are equidistantly spaced in the circumferential direction and each preferably forms a single tab 40. Each L-shaped tongue 41 can be arranged in such a way that it is arranged between an injection-molding section 32 and a weld line 33 spaced apart from the injection-molding section 32, preferably in the middle.

(53) As can also be seen from FIG. 10, a U-shaped recess 46 is formed in the set-back flange 36 around each L-shaped tongue 41, by means of which the effective length of the first section of the L-shaped tongue 41 is extended and which enables the L-shaped tongue 41, or the free end forming the tab 40, to be deflected in a flexurally elastic manner.

(54) The recess 46 extends, as shown in FIGS. 11 and 13, from the relevant outer edge 38a, 38b of the set-back flange 36 parallel to the axis of rotation X and ends in alignment with the inner edge 37a, 37b of the set-back flange 36.

(55) The section D-D according to FIG. 10, shown in FIG. 14, shows a section through the injection-molding section 32 and it can be seen that, in the preferred embodiment, this is set back in relation to the end face 11, but protrudes beyond the set-back flange 36 in the direction of the axis of rotation X.

(56) FIGS. 15-19 show an outer part 30 according to a fifth exemplary embodiment. The outer part 30 differs from the exemplary embodiment according to FIGS. 9-14 in the design of the set-back flange 36 and the connection between the L-shaped tongues 41 and the set-back flange 36.

(57) The set-back flange 36 can have a tapering shape or be trapezoidal, wherein the set-back flange 36 can be made increasingly tapered with a decreasing radius—in relation to the axis of rotation X. The tapering shape of the flange can be seen in FIG. 17.

(58) Alternatively, the set-back flange 36 can be cuboid, whereby a distance between the respective outer edges 38a, 38b and the respective inner edges 37a, 37b of the set-back flange 36 is equidistant.

(59) As can be seen in particular from FIGS. 16 and 17, the L-shaped tongue 41 is connected to the set-back flange 36 via a shoulder 39. The L-shaped tongue 41 can be formed by a transition between the L-shaped tongue 41 and the set-back flange 36, which can be wedge-shaped, for example. The shoulder 39 is adapted to the shape of the set-back flange 36, whereby parallel to the axis of rotation X, a wall thickness of the shoulder and the flange (together) remain approximately constant and thus greater stresses can be reduced in the transition between the L-shaped tongue 41 and the circumferential and set-back flange 36.

(60) Moreover, it can also be seen that 3 L-shaped tongues 41 are formed both on the first end face 11 and on the second end face 12, each of which forms a tab 40. The arrangement of the L-shaped tongues 41 or the tabs 40 can preferably be selected such that the L-shaped tongues 41 or the tabs 40—as shown—are angularly offset on opposite end faces 11, 12 and can also be arranged angularly offset to the injection-molding sections 32 and the weld lines 33.

(61) FIGS. 20 to 21c show a fifth exemplary embodiment, the multi-component gear being designed approximately analogously to the exemplary embodiment shown in FIGS. 15-19. In contrast to the exemplary embodiment shown up to now, the tab 40 has a cut-out 48 which, as shown, can break through the tab in the middle in such a way that the second partial area of the tab 40 is formed with multiple tongues.

(62) Each tab 40 or L-shaped tongue 41 protrudes in the axial direction from the set-back flange 36 and projects beyond the relevant end face 11, 12. The part of the tab 40 aligned in the axial direction corresponds to the first partial area, while the second partial area is aligned approximately radially or secantially and can encompass the end faces of the inner part 20. For this purpose, the tabs 40 protrude beyond the lateral surface 34, see FIGS. 21b and 21c.

(63) FIGS. 20 and 21 show a sixth exemplary embodiment, the multi-component gear being designed approximately analogously to the exemplary embodiment shown in FIGS. 15-19. In contrast to the exemplary embodiments shown so far, the tab 40 has a cut-out 48 which, as shown, can break through the tab in the middle in such a way that the second partial area of the tab 40 is formed with multiple tongues.

(64) Each tab 40 or L-shaped tongue 41 protrudes in the axial direction from the set-back flange 36 and projects beyond the relevant end face 11, 12. The part of the tab 40 aligned in the axial direction corresponds to the first partial area, while the second partial area is aligned approximately radially or secantially and can encompass the end faces of the inner part 20.

(65) The cut-out 48 increases the axial deformability of the tabs 40 and at the same time reduces the axial shrinkage stresses. It should be noted at this point that each tab 40 can have a plurality of cut-outs 48, as a result of which the tab 40 can have a plurality of tongues 41.

(66) With reference to FIGS. 22 to 23c, a seventh exemplary embodiment is shown, the cut-out 48 breaking through both the tab 40 and the set-back flange 36. In this exemplary embodiment, the tab 40 is U-shaped, the first partial area being formed in two or more parts and the second partial area connecting the ends of the first partial area. In the illustrated embodiment, the cut-out 48 extends in the shape of a cuboid parallel to the longitudinal axis through the tab 40 and through the set-back flange 36, which avoids an undercut in the second part and increases the deformability in the area of the tab 40 or reduces the rigidity there.

LIST OF REFERENCE NUMERALS

(67) 1 Multi-component gear 2 Planet gear 2 Gear 3 Planetary gearset 4 Planet carrier 11 First end face 12 Second end face 13 Lateral surface 20 Inner part 21 Inner ring 22 Outer ring 24 Lateral surface 26 Rolling element 27 Sealing disk 30 Outer part 32 Injection-molding section 33 Weld line 34 Lateral surface 35 Toothed ring 36 Flange 37 Inner edge 38 Outer edge 39 Shoulder 40 Tab 41 Tongue 42 Transition area 43 Transition radius 45 Free area 48 Cut-out 50 Pocket B2 Width of 20 B3 Width of 30 B4 Width of 40 D13 Inner diameter of 13 D24 Outer diameter of 24 D27 Outer diameter of 27 D34 Inner diameter of 34 D40 Diameter of 40 D45 Inner diameter of 45 D50 Diameter of 50 X Axis of rotation