DE102016223820B4 - Planetary gear with a ring gear fixed stationary on the housing side, and method for manufacturing a planetary gear - Google Patents

Abstract

Planetary gear, with:- a ring gear (H), which is formed by an annular body which has an outer peripheral surface (H3), a first end face (H1), a second end face (H2) and internal teeth (H4), and- a gear housing (G), which forms a ring gear seat (G1), into which the ring gear (H) is pressed axially, whereby a profiling (P) is formed on the ring gear (H) in the area of its outer peripheral surface (H3), which is part of the Pressing the ring gear (H) into the ring gear seat (G1), the ring gear seat (G1) deformed to form a complementary geometry, characterized in that the profiling (P) comprises at least one profile row (P1) which primarily rotates the ring gear (H) in a first direction within the ring gear seat (G1), and comprises at least one profile row (P2) which primarily blocks rotation of the ring gear (H) in a direction opposite to the first direction within the ring gear seat (G1).

Description

field of invention

The invention relates to a planetary gear with a gear housing and a ring gear which has internal teeth which are concentric to a gear axis X, the ring gear being arranged in the gear housing in a rotationally fixed manner. Furthermore, the invention also relates to a method for manufacturing a planetary gear with a stationary ring gear fixed in a gear housing.

Out of US8216107B2 a planetary gear is known which has a ring gear fixed in a rotationally fixed manner in a housing of the planetary gear. The ring gear sits there in the area of a radial parting plane between two pot sections of a transmission housing. In the area of its outer circumference, the ring gear has projections which engage in complementary geometries prepared on the housing side. A movement play is provided between the gear housing and the ring gear, which allows a slight axial movement of the ring gear relative to the gear housing. This makes it possible to mechanically decouple the ring gear and the transmission housing to such an extent that the transmission of vibrations from the ring gear into the transmission housing is reduced.

From the DE 23 47 372 A1 shows a planetary gear or an arrangement with a ring gear of the genus. A profiling in the form of teeth is formed on the outside of the ring gear, which is partially plastically deformed when the ring gear housing is pressed in and forms a connection with the housing.

object of the invention

The object of the invention is to provide solutions that make it possible, in a manner that is advantageous in terms of production technology, to anchor a ring gear of a planetary gear in a rotationally fixed manner in a gear housing.

Solution according to the invention

This object is achieved according to the invention by the features of claim 1.

• - einem Hohlrad das durch einen Ringkörper gebildet ist, der eine Außenumfangsfläche, eine erste Stirnfläche, eine zweite Stirnfläche und eine Innenverzahnung aufweist, und
• - einem Getriebegehäuse das einen zylindrischen Hohlradsitz bildet in welchen das Hohlrad axial eingepresst ist, wobei
• - an dem Hohlrad im Bereich seiner Außenumfangsfläche eine Profilierung ausgebildet ist, die im Rahmen des Einpressens des Hohlrades in den Hohlradsitz,

den Hohlradsitz unter Bildung einer Komplementärgeometrie deformiert, ist erfindungsgemäß vorgesehen, dass die Profilierung mindestens eine Profilreihe umfasst, die primär eine Drehung des Hohlrades in einer ersten Richtung innerhalb des Hohlradsitzes sperrt, und mindestens eine Profilreihe umfasst, die primär eine Drehung des Hohlrades in einer der ersten Richtung entgegengesetzten Richtung innerhalb des Hohlradsitzes sperrt.A planetary gear, with:

• - A ring gear formed by an annular body having an outer peripheral surface, a first end face, a second end face and internal teeth, and
• - A gear housing that forms a cylindrical ring gear seat in which the ring gear is pressed axially, wherein
• - a profiling is formed on the ring gear in the area of its outer peripheral surface, which is formed as part of the pressing of the ring gear into the ring gear seat,

deforms the ring gear seat to form a complementary geometry, the invention provides that the profiling comprises at least one row of profiles that primarily blocks rotation of the ring gear in a first direction within the ring gear seat, and comprises at least one row of profiles that primarily blocks rotation of the ring gear in one of the first direction opposite direction blocks within the ring gear seat.

This advantageously makes it possible to create a planetary gear in which the ring gear can be fixed with high strength in a cylindrical ring gear seat of a gear housing that can be realized inexpensively and with narrow shape tolerances by simple machining.

According to a particularly preferred embodiment of the invention, the profiling provided on the outer circumference of the ring gear in the form of a micro-profiling forms a notched profile that rises above a cylindrical basic geometry of the outer circumferential surface and presses into the material of the ring gear seat and/or cuts into this material. The basic cylindrical geometry is preferably dimensioned in such a way that a transition or slight press fit of the ring gear in the ring gear seat would result without the formation of the profile. The radial elevation of the profile is preferably in the range of 0.25% to 1.15% of the diameter of the profiled peripheral surface.

According to a particular aspect of the present invention, the profiling formed on the outer circumference of the ring gear is produced by plastic deformation of the ring gear. This achieves a special effect, which consists in the fact that, by excavating the profiling from the basic geometry of the ring gear, in the immediate vicinity of the excavation, there is also space provided, into which material of the transmission housing can penetrate. A retaining geometry that is complementary to the profiling is thus formed during the pressing on the transmission housing, which extremely effectively supports the ring gear in the circumferential direction without play, without the ring gear seat being excessively stretched or strained.

The plastic deformation of the outer peripheral portion of the ring gear is preferable accomplished by a burnishing tool whose burnishing head rolls on the ring gear and in doing so plastically pushes the profiling out of the basic geometry. The profiling can also be formed by a chisel or punch tool. As an alternative to plastic deformation, the formation of the profile on the outer circumference of the ring gear can also be accomplished by machining, in particular by broaching. However, the formation of the profiling by means of metal forming is preferred because of the special effect described above.

Furthermore, the formation of the profiling on the outer circumference of the ring gear is preferably carried out as part of a manufacturing step preceding the hardening of the ring gear. The profiling can then be hardened, in particular nitrided, together with the internal toothing.

The profiling can also advantageously be designed with regard to its cross section in a radial plane of the ring gear in such a way that a particularly effective positive support of the ring gear results in both circumferential directions in the ring gear seat.

The invention is preferably used in transmission systems in which the transmission housing is made of an aluminum material and the ring gear is made of a steel material or at least of a material with a strength exceeding the strength of aluminum.

Furthermore, circumferential grooves can advantageously be formed in the region of the ring gear seat, which serve to receive chips that are pushed off the ring gear seat as part of the pressing in of the ring gear. This makes it possible to produce the complementary geometry in the ring gear seat as a broaching profile, with the ring gear then acting directly as a one-way broaching tool that remains in the transmission housing, including the removed chips.

According to a further particular aspect of the present invention, the ring gear is designed in such a way that the outer circumferential surface bearing the profile also includes a non-profiled circumferential zone which acts as a guide surface when the ring gear is pressed in and as a centering surface when the end position is reached. The inside diameter of the ring gear seat and the outside diameter of the ring gear are matched to one another with regard to this non-profiled zone in such a way that a transition or press fit results. If necessary, the formation of the non-profiled zone can be brought about as part of a processing step subsequent to the hardening of the ring gear, e.g. by grinding to the final dimension. This in turn makes it possible to first form the profiling on the entire peripheral surface and then to remove it again at least partially locally to implement the guide zone.

The concept according to the invention includes in particular the creation of a notched connection in connection with a press fit or a transition fit of a ring gear in the region of its seat in a transmission housing. This notch connection is preferably realized by structures that are formed by means of plastic deformation, in particular by rolling on the outer peripheral area of the ring gear. In the area of the ring gear seat, a collecting groove is preferably provided at the end of the sliding seat, which collects any chips and other dirt that may have been pushed off during the joining process. During joining, this groove is initially crossed by a non-profiled peripheral section, so that the chips that may then fall into it must remain in this groove.

With regard to the production of a planetary gear according to the invention, the object specified at the outset is also achieved by a method for producing a planetary gear with a gear housing and a ring gear anchored therein, in which, as part of a joining step, the ring gear is pressed into a ring gear seat formed in the gear housing, wherein in the context of a manufacturing step of the ring gear preceding this joining step, a profiling is formed on its outer peripheral region, which is formed and/or cuts into the ring gear seat in the course of the joining step, forming a complementary geometry. With regard to the formation of the profiling, reference is made to the above statements.

The ring gear is preferably pressed in against the stop, i.e. until the front face of the ring gear in the press-in direction is in contact with a corresponding mating face of the gear housing.

character list

• 1 eine Schnittdarstellung zur Veranschaulichung des Aufbaues des von der Erfindung betroffenen Bereiches eines Planetengetriebes mit einem Getriebegehäuse und einem darin stationär festgelegten Hohlrad;
• 2 eine perspektivische Darstellung eines erfindungsgemäß außenseitig profilierten Hohlrades mit einer nicht-profilierten Führungs- und Zentrierumfangszone;
• 3 zwei Detail-Schnittdarstellung zur Veranschaulichung eines bevorzugten Querschnitts der Profilierung in zwei axial abfolgenden Radialschnittebenen des Hohlrades, wobei die obere Schnittdarstellung die Profilierung in einer Ebene zeigt, die im Uhrzeigersinn stützt, und die untere Schnittdarstellung eine Ebene zeigt, in welcher die Profilierung eine Drehung des Hohlrades im Gegen-Uhrzeigersinn stützt;

Further details and features of the invention result from the following description in conjunction with the drawings. Show it:

• 1 a sectional view to illustrate the structure of the area affected by the invention of a planetary gear with a gear housing and a ring gear stationary fixed therein;
• 2 a perspective view of a ring gear profiled on the outside according to the invention with a non-profiled guiding and centering peripheral zone;
• 3 Two detailed sectional views to illustrate a preferred cross section of the profiling in two axially sequential radial sectional planes of the ring gear, with the upper sectional view showing the profiling in a plane that supports clockwise direction, and the lower sectional view showing a plane in which the profiling causes a rotation of the ring gear counter-clockwise;

Detailed description of the figures

The representation after 1 shows a portion of a planetary gear according to the invention. This includes a ring gear H, which is formed by a ring body having an outer peripheral surface H3, a first end face H1, a second end face H2 and an internal toothing H4. Furthermore, the planetary gear comprises a gear housing G which forms a ring gear seat G1 into which the ring gear H is pressed axially.

A profiling P is formed on the ring gear H in the area of its outer circumferential surface H3, which deforms the ring gear seat H1 while the ring gear H is being pressed into the ring gear seat H1, forming a complementary geometry.

The profiling P formed on the outer peripheral surface H3 forms a notched profile that rises above a cylindrical basic geometry of the outer peripheral surface H3 and, within the scope of this oversize, presses into the material of the ring gear seat G1 and/or cuts into this material.

In the exemplary embodiment shown, the profiling P formed on the outer circumference of the ring gear H is produced by plastic deformation of the ring gear H, this plastic deformation being accomplished here by a burnishing tool. This reshaping takes place as part of the manufacture of the ring gear as part of a manufacturing step that precedes the hardening of the ring gear H. As below in connection with 3 The cross section of the profiling P in a sectional plane radial to the axis of the ring gear is selected in such a way that the ring gear H is supported in a form-fitting manner in the circumferential direction in the ring gear seat G1. The transmission housing G is here made from an aluminum material and the ring gear H is made from a steel material.

As can also be seen, a circumferential groove G2 is formed on the transmission housing G in the area of the ring gear seat H1 to accommodate any chips that are pushed off the ring gear seat G1 as part of the pressing in of the ring gear H. The circumferential groove G3, which can also be seen in this illustration, serves to accommodate a retaining ring, by means of which the ring gear H is secured in the transmission housing G in an axially form-fitting manner.

The perspective view 2 illustrates the design of the outer peripheral surface H3 of the ring gear H. The internal toothing H4 is not shown here; it is preferably produced before the profiling P is formed. As can be seen from this illustration, the outer peripheral surface H3 includes a non-profiled peripheral zone H5 that functions as a guide and centering surface. The outer diameter of this cylindrical peripheral zone H5 is adjusted in such a way that it sits in the ring gear seat G1 of the transmission housing G with a transition or press fit and guides and centers the ring gear H. The non-profiled area H5 can also be realized on a stepped peripheral section of the ring gear H. In terms of its basic geometry, however, it preferably corresponds to that area of the ring gear in which the profile P is preferably formed by local plastic deformation.

The ring gear shown here has an outside diameter of 193mm. The elevation of the profiling P is 1mm here at the radially outermost points. In the case of ring gears with larger or smaller diameters, this ratio of profile height to diameter is preferably retained. The profiling P here forms four profile rows P1, P2, P3 and P4. The profile rows P1 and P3 primarily block a clockwise rotation of the ring gear, the profile rows P2 and P4 primarily block a counterclockwise rotation of the ring gear H. The profiling P is made by a rolling tool

The representation after 3 shows the at the ring gear 2 trained profiling in two axially spaced radial planes. The upper sectional view shows a profile row P1, which locks the ring gear H against clockwise rotation. The sectional view below shows the ring gear H in a radial sectional plane, in which the row P2 of the profiling blocks the ring gear H against counterclockwise rotation. The difference in height between the lowest points of the profile and the crests of the same is 1 mm here.

Claims (10)

Planetary gear, with: - a ring gear (H), which is formed by an annular body which has an outer peripheral surface (H3), a first end face (H1), a second end face (H2) and internal teeth (H4), and - a gear housing (G), which forms a ring gear seat (G1), into which the ring gear (H) is pressed axially, whereby - a profile (P) is formed on the ring gear (H) in the area of its outer peripheral surface (H3), which is part of the Pressing the ring gear (H) into the ring gear seat (G1), the ring gear seat (G1) deformed while forming a complementary geometry, characterized in that the profiling (P) comprises at least one profile row (P1) which primarily rotates the ring gear (H) in a first direction within the ring gear seat (G1), and comprises at least one profile row (P2) which primarily blocks rotation of the ring gear (H) in a direction opposite to the first direction within the ring gear seat (G1). planetary gears claim 1 , characterized in that the profile (P) formed on the outer peripheral surface (H3) forms a notched profile which rises above a cylindrical basic geometry of the outer peripheral surface (H3) and is pressed into the material of the ring gear seat (G1) and/or into this material cuts in. planetary gears claim 1 or 2 , characterized in that the profile (P) formed on the outer circumference of the ring gear (H) is produced by plastic deformation of the ring gear (H). planetary gears claim 3 , characterized in that the plastic deformation of the outer peripheral area of the ring gear (H) is brought about by a burnishing tool. Planetary gear according to at least one of Claims 1 until 4 , characterized in that the formation of the profile (P) on the outer circumference of the ring gear (H) is accomplished by machining. Planetary gear according to at least one of Claims 1 until 5 , characterized in that the formation of the profiling (P) on the outer circumference of the ring gear (H) in the context of a hardening of the ring gear (H) upstream manufacturing step is accomplished. Planetary gear according to at least one of Claims 1 until 6 , characterized in that the cross section of the profiling (P) is chosen so that a positive support of the ring gear (H) in the circumferential direction in the ring gear seat (G1) results. Planetary gear according to at least one of Claims 1 until 7 , characterized in that the gear housing (G) is made of an aluminum material and the ring gear (H) is made of a steel material, and/or that circumferential grooves (G2) are formed in the area of the ring gear seat (G1) for receiving chips that are in the frame be pushed off the ring gear seat (G1) before the ring gear (H) is pressed in. Planetary gear according to at least one of Claims 1 until 8th , characterized in that the outer peripheral surface (H3) comprises a non-profiled peripheral zone (H5) which acts as a guiding and centering surface. Method for producing a planetary gear with a gear housing (G) and a ring gear (H) anchored therein, in which, as part of a joining step, the ring gear (H) is pressed into a ring gear seat (G1) formed in the gear housing (G), the frame a manufacturing step of the ring gear (H) preceding this joining step, a profiling (P) is formed on its outer peripheral area, which forms and/or cuts into the ring gear seat (G1) within the scope of the joining step, forming a complementary geometry, characterized in that the profiling ( P) is formed in such a way that it comprises at least one profile row (P1) that primarily blocks rotation of the ring gear (H) in a first direction within the ring gear seat (G1), and at least one profile row (P2) that primarily rotates of the ring gear (H) in a direction opposite to the first direction within the ring gear seat (G1).

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