EP3362705A1

EP3362705A1 - Hollow gear with inner toothing and crown toothing, as well as method for the production thereof and manual transmission having a hollow gear of this type

Info

Publication number: EP3362705A1
Application number: EP16766007.5A
Authority: EP
Inventors: Benjamin Schneider
Original assignee: ZF Friedrichshafen AG
Current assignee: ZF Friedrichshafen AG
Priority date: 2015-10-13
Filing date: 2016-09-15
Publication date: 2018-08-22
Also published as: WO2017063813A1; CN108138937A; CN108138937B; JP6783304B2; DE102015219855A1; JP2018531350A; US20180306301A1; US10753451B2

Abstract

The invention relates to a hollow gear for a planetary transmission, having a sprocket (110) which is designed with an inner toothing (120) on the inner circumferential surface thereof and with a flange (130) on the outer circumferential surface thereof, which is radially projecting and axially protruding on one side, wherein the flange (130) forms a circumferential cuff (131) and a collar-like protrusion (132), and the collar-like protrusion (132) is provided with a crown toothing (140). The crown toothing (140) is continuous and also projects through the cuff (131) in the axial direction (L). The invention also relates to a method for producing a hollow gear of this type via the broaching of the crown toothing (140), and a manual transmission having at least one hollow gear of this type.

Description

Ring gear with Innenverzahnunq and crown toothing, and method for its

Production and manual transmission with such ring gear

The invention relates to a ring gear for a planetary gear, which has an internal toothing and a crown toothing. The invention further relates to a manufacturing method for such a ring gear and a transmission with at least one such ring gear.

DE 199 61 988 A1 describes an arrangement for torque transmission between a ring gear and a driving part, wherein in the ring gear on the driving part facing side a crown toothing is arranged, are inserted into the teeth of the driving part in the axial direction (see Fig. 2). Furthermore, a further arrangement for transmitting torque is described, in which a crown toothing is arranged in the driving part, in which a crown toothing engages, which is located on a radially above the ring gear projecting flange (see Fig. 3).

The prior art further refers to DE 102 30 861 A1, in particular to the embodiments of a plug connection between a ring gear and a ring gear carrier shown in FIGS. 1, 6, 7 and 8 and 10. This embodiment has in common that the ring gear on its outer peripheral surface has a circumferential, radially projecting flange which projects axially on an end face of the ring gear, wherein the axial projection is formed with a crown toothing.

The invention has for its object to provide an improved ring gear of the kind that at least one associated with the prior art disadvantage does not or at least reduced.

This object is achieved by an inventive ring gear with the features of claim 1. With independent claims, the invention also extends to an inventive method for producing a ring gear according to the invention and to a transmission for a motor vehicle or Commercial vehicle, in particular an automatic transmission comprising at least one inventive and / or inventively produced ring gear. Preferred developments and embodiments of the invention will become apparent for all subject matter of the dependent claims, the following description and the figures.

The ring gear according to the invention (Planetengetriebehohlrad) has a ring gear, which is formed on its inner peripheral surface with an internal toothing and on its Au ßenumfangsfläche a radially projecting and unilaterally (ie on an end face of the ring gear or ring gear) axially projecting flange, which through this flange circumferential collar and a collar-like projection are formed and the collar-like projection is provided with a crown toothing. The invention provides that the crown toothing is formed continuously and also projects axially through the collar. D. h., The crown teeth is not only formed in the collar-like projection, but also extends into the collar, such that the crown teeth is formed continuously and the flange extends axially.

Under a sprocket, in particular, a ring-like and preferably solid trained body is understood having an inner peripheral surface, a Au ßenumfangsfläche and two end faces or end faces which connect the inner peripheral surface and the Au ßenumfangsfläche in a substantially radial extent with each other. The inner toothing formed on the inner circumferential surface is a running toothing provided for the direct engagement of planetary gears. When the crown gear is a spline, which is provided for the torsion-free connection with a ring gear or the like. The ring gear or its toothed rim has a symmetry or rotation axis through which an axial direction and perpendicular thereto a radial direction can be defined.

At the ring gear according to the invention, the crown toothing is formed not only in the flange portion projecting beyond the end face, but extends axially or in an axial direction through the entire flange. This results in several advantages. On the one hand can be achieved without changing the structural dimensions, a significant weight savings or Drehassenreduktion. On the other hand, there are new design possibilities for the crown toothing, whereby a higher load capacity, easier installation and / or simplified production can be achieved.

Preferably, the tooth gaps of the crown teeth are formed in the axial direction with a constant or constant gap width. D. h., The width of the adjacent tooth flanks resp. Grooved edges (see below) trained

Tooth gaps resp. Grooves (see below) and related thereto

The opening angle between these tooth flanks (that is to say the mutually facing tooth flanks of adjacent teeth) does not change over the axial course of the crown toothing.

Strictly speaking, the toothing projecting through the flange is a spline, wherein only its toothed section formed in the axial projection of the flange represents a crown spline in the conventional sense. Preferably, the tooth gaps of the spline or crown teeth are formed radially continuous only in this toothing section, so that they can be penetrated in a known manner by the counter teeth on the ring gear.

The formed in the collar of the flange toothing portion of the crown or spline toothing preferably has groove-like tooth gaps, each formed with a groove bottom and thus are not continuous in the radial direction. Preferably, the groove-like tooth spaces formed in the collar each have two mutually circumferentially spaced groove flanks and one, in particular curved in the circumferential direction, groove bottom. Preferably, the groove flanks are substantially straight or planar and may have an inclination angle between 0 ° and 25 ° with respect to the radial direction. Preferably, all tooth spaces or all grooves of the crown teeth are formed identically, with a non-identical design, whereby z. B. a mounting position can be specified, is possible. In the groove-like tooth gaps, free-passage transitions can be formed between the groove flanks and the groove bottoms. By these free-cutting transitions, which are preferably formed over the entire axial length of the grooves, stress peaks caused by notch effect are reduced. In addition, the

Gegenver toothing be formed sharp-edged on the ring gear carrier to be connected, which has an advantageous effect both on its production costs and costs and on the installation effort. The freistichartigen transitions are preferably generated in the machining of the crown toothing or generated and can serve during production as a run-off zone for the tool or tools and / or enable Spanausleitung, so that in particular not previously used manufacturing process for the production of Crown gearing can be used.

The ring gear according to the invention is preferably in one piece, d. H. in one piece or from a workpiece. Preferably, the ring gear is formed of a metal material and in particular of a steel material. Preferably, at least the crown or spline toothing is produced by machining.

A preferred method for producing a ring gear according to the invention according to the preceding explanations comprises at least the following steps, which are carried out in particular automatically:

- Providing an annular blank, which is already formed with a flange;

- Generating the internal toothing through interiors, possibly also

Swirling spaces, or the like; and

- Generate the crown or spline on the flange through Tubusräumen.

A manufacturing method with the above-mentioned steps is the subject of the first independent patent claim. The internal toothing and the crown toothing can also be produced in reverse order. The collar-like protruding flange portion may, prior to generating the spline, in particular by reshaping and / or cutting preparation of the blank (in the course of prefabrication), or even after the generation of the spline, for example. By turning (the tooth spaces of the already produced plug or crown teeth are made radially continuous), are made ,

The blank is, for example, a massive forged or turned part which was produced in a preceding manufacturing process. The inner or running toothing is produced according to the method in a conventional manner. The crown or spline toothing is produced by tube cavities (pot broaching), which represents an innovation, since crown gears on ring gears of the kind concerned have hitherto been produced by milling or the like and in particular by so-called percussion turning. The invention thus also provides an alternative production method for ring gears of the type in question.

As already mentioned above, the design according to the invention of a continuous crown toothing, in particular the groove-like formation of continuous or axially projecting tooth gaps, enables a simplified production of the crown toothing and thereby also a simplified manufacture of the ring gear, which is accomplished by tube cavities according to the above-mentioned method ,

When Tubusräumen the blank or the workpiece is pulled or pushed through a tubular broaching tool, with successive relative movement successively the crown toothing is produced by cutting material removal on the workpiece. The workpiece is meanwhile enclosed on all sides by the tubular broaching tool, with the crown toothing typically being completely produced in one operation or in a clearing pass. Usually there is no post-processing. This process can also be referred to as outer tube spaces. The Tubusräumen or outer Tubusräumen done on a Tubusräummaschine, in particular on a vertical or horizontal Tubusräummaschine. It is preferably provided that the broaching tool used to produce the crown teeth has so-called scraper bars. The scraper rails are intended, inter alia, for chip ejection. The scraper bars are in particular designed such that at the same time the free-stroke transitions between the groove flanks and the groove grounds can be generated at the same time.

The invention will be explained in more detail below with reference to the figures by way of example and not by way of limitation. The features shown in the figures and / or explained below can, even detached from concrete combinations of features, further develop the invention.

Fig. 1 shows a sectional view of the sprocket of an inventive

Planetengetriebehohlrads and an attached ring gear carrier.

Fig. 2 shows the sprocket of Fig. 1 in an enlarged sectional view.

Fig. 3 shows the sprocket of Fig. 1 in a different sectional view, according to the sectional profile indicated in Fig. 2.

FIG. 4 illustrates the production of the crown toothing on the sprocket of FIG. 1 through tube cavities. FIG.

Fig. 1 shows an analog representation of DE 199 61 988 A1, the sprocket 1 10 of a ring gear 100 according to the invention for a planetary gear. The peripheral edges are not shown for ease of illustration. The ring gear 100 has a symmetry or rotation axis L, through which an axial direction and perpendicular thereto a radial direction R are defined. On the ring gear 1 10 a ring gear 200 is attached, which also serves as a driving part for rotationally fixed connection with a shaft or other gear. Likewise, it may be a holding part which holds the ring gear 100. The ring gear carrier 200 is a sheet metal component manufactured by punching and forming. The ring gear 1 10 is formed on its inner circumference with an internal toothing 120, which meshes with the planetary gears of the planetary gear. In particular, it is an involute and / or helical gearing. On its outer peripheral surface, the ring gear 1 10 has a circumferentially formed flange 130. The projection-like flange 130 includes two flange portions 131 and 132 (see FIG. 2). The only over a portion of the width of the ring gear 1 10 extending first flange portion 131 leads to a radial thickening of the ring gear 1 10 and thereby forms a circumferential collar. The on the side of Hohlradträgers 200 axially beyond the end face 1 15 of the ring gear 1 10 protruding or projecting second flange portion 1 32 forms a collar-like projection on which the ring gear 200 is attached.

The circumferential flange 130 is formed over the entire circumference of the ring gear 1 10 with a crown or spline 140. The ring gear carrier 200 has a corresponding counter-toothing, with which this is plugged or inserted on the crown gear 140, whereby a rotationally fixed connection. The axial securing takes place with the aid of a securing ring 300.

Unlike the ring gears of the same type known from the prior art, the crown toothing 140 formed on the flange 130 is continuous and protrudes or extends through the flange 130 in the axial direction L. This involves many advantages, as explained above.

In the projecting second flange portion 132 of the crown gear 140, the tooth spaces 142 are formed continuously in the radial direction R. The tooth spaces 142 continue in the first collar-like flange section 131 as groove-like tooth gaps with the same gap width w, as can be seen in FIGS. 2 and 3. There, the tooth gaps 142 extending between adjacent teeth 141 have two in

Circumferential direction U mutually spaced tooth flanks or groove edges 143 and a curved in the circumferential direction U groove bottom 144. The straight and mutually symmetrical groove flanks 143 may have an inclination angle a between 0 ° and 25 ° with respect to the radial direction R of the ring gear 1 10.

Between the groove flanks 143 and the groove bottoms 144, axially extending free-stroke-like transitions 145 are formed. The flange 130 protruding Tooth gaps or grooves 142 have a constant in the axial direction L, ie, over its axial course not changing contour. The groove bases 144 extend in the axial direction or parallel to the axis of symmetry or rotation L, as shown in FIG. 2.

In Fig. 4, the production of the crown gear 140 is illustrated. FIG. 4 a shows a prefabricated ring gear 100 ', which is formed in one piece from a steel material and has a flange 130 and an internal toothing 120. The ring gear 100 ', which is still formed without crown toothing 140, is clamped onto a push rod 20 and pressed by means of this push rod 20 through a tubular broaching tool 10, as shown in FIG. 4b (the pushing is effected from left to right). The broach 10 has a tube 1 1 with internal tool inserts 12. By means of the tool inserts 12, a crown toothing 140 according to FIGS. 2 and 3 is produced on the flange 130 of the ring gear 100 'by cutting material removal. All teeth 141 and

Tooth gaps or grooves 142 of the crown gear 140 formed in one operation or in a clearing pass. This process is referred to as Tubusräumen (the not to scale representation in Fig. 4b is only to explain the principle of Tubusräumens).

The crown toothing 140 produced by the procedure explained above is accordingly an axially extending tube-cleared spline. The second axially projecting flange portion 132 of the flange 130 can, in particular by frontal boring, before or else only after the tube cavities are generated.

REFERENCE CHARACTERS

10 broaching tool

1 1 tube

12 tool insert

0 push rod

100 ring gear

1 10 sprocket

1 15 front side

120 internal toothing (running toothing)

130 flange

131 first flange section (collar)

132 second flange section (projection)

140 crown toothing (splining)

141 tooth

142 tooth gap, groove

143 tooth flank, groove flank

44 groove base

145 transition

200 ring gear carrier

300 circlip

L axial direction (symmetry axis)

R radial direction

U circumferential direction

a angle

w width

Claims

claims

1 . A ring gear (100) for a planetary gear, with a ring gear (1 10) formed on its inner peripheral surface with an internal toothing (120) and on its outer peripheral surface has a radially projecting and one-sided axially projecting flange (130), wherein the flange (130 ) a circumferential collar (131) and a collar-like projection (132) and the collar-like projection (132) is provided with a crown toothing (140), characterized in that the crown toothing (140) is formed continuously and also the collar (131) protrudes axially.

2. ring gear (100) according to claim 1, characterized in that the tooth gaps

(142) of the crown toothing (140) in the axial direction (L) are formed with a constant gap width (w).

3. ring gear (100) according to claim 1 or 2, characterized in that in the collar-like projection (132) the tooth gaps (142) of the crown toothing (140) are formed radially continuous.

4. ring gear (100) according to one of the preceding claims, characterized in that in the collar (131) the tooth spaces (142) of the crown toothing (140) are formed like a groove and each having a groove bottom (144).

5. ring gear (100) according to claim 4, characterized in that the groove-like tooth spaces (142) each have two circumferentially (U) mutually spaced groove flanks (143) and in the circumferential direction (U) curved groove bottom (144).

6. ring gear (100) according to claim 5, characterized in that the groove flanks

(143) are straight and with respect to the radial direction (R) a

Inclination angle (a) between 0 ° and 25 °.

7. ring gear (100) according to claim 5 or 6, characterized in that between the groove flanks (143) and the groove bottoms (144) freistichartige transitions (145) are formed.

8. ring gear (100) according to one of the preceding claims, characterized in that it is made in one piece from a metal material.

9. A method for producing a ring gear (100) according to one of the preceding claims, comprising the steps:

- Providing an annular blank (100 '), which is already formed with a flange (130);

- Generating the internal teeth (120) by interiors; and

- Generating the crown toothing (140) on the flange (130) through tube cavities.

10. Manual transmission for a motor vehicle or commercial vehicle, in particular

An automatic transmission comprising at least one ring gear (100) formed according to any one of claims 1 to 8 and / or produced by a method according to claim 9.