DE102019129724A1 - Planet carrier with segmented spline and integrated spacer elements, kit of planetary gear with shaft and method for producing a planetary spline - Google Patents

Abstract

The invention relates to a planet carrier (1) for use in a motor vehicle, with a planet carrier cheek (2) which has internal teeth (5) for torque transmission between the planet carrier (1) and the shaft (4) in a receptacle (3) for a shaft (4) ), wherein the internal toothing (5) extends segment-like over only part of the circumference of the receptacle (3) and thereby forms at least one internal toothing segment (6), with at least one spacing tooth (7) adjoining the internal toothing segment (5) in the circumferential direction. is bent in the axial direction towards the shaft (4) so that its free end (9) is prepared to come into contact with a shaft-connected component in order to keep the shaft (4) at a distance in the operating state. The invention also relates to a kit comprising a planetary gear with such a planet carrier (1) and a shaft (4). The invention also relates to a method for producing a plug-in toothing provided for a form fit with an external toothing (13) of a shaft (4) on a planet carrier cheek (2), an inner circumferential contour being punched in the area of a receptacle (3) of a sheet metal plate, which is divided into internal toothing segments (6) separated from one another by at least one spacing tooth (7), comprising at least one torque transmission tooth (18), the at least one torque transmission tooth (18) being shorter than the spacing tooth (7), measured in the radial direction, with, for example In a subsequent step, the spacer tooth (7) is folded over from its radial direction (16) by a bend in the axial direction (15).

Description

The invention relates to a planet carrier for a motor vehicle planetary gearbox with a planet carrier cheek which has internal toothing for torque transmission between the planetary carrier and the shaft in a receptacle for a shaft, which can be designed in the manner of a pin, hub and in particular a housing pin, the internal toothing being segment-like only over one Part of the circumference of the receptacle extends, ie less than 360 °, and thereby forms at least one internal tooth segment.

Basically there are already planet carriers with internal gears, such as those from DE 10 2007 003 676 A1 are known. A planet carrier for a planetary gear is presented there, the planet carrier comprising a planet carrier base body which has a central recess for receiving an output shaft. It is particularly pointed out in this patent application that an annular tooth element which has internal teeth is arranged in the central recess in a rotationally fixed manner. The annular tooth element has a profile on its outer circumference. The circumference of the recess also has a complementary profile to form a form-fitting connection. In this way, it is possible, by pressing the tooth element into the planetary base body, to provide a non-positive as well as a form-fitting connection between the tooth element and the planetary base body.

The planetary base body also has a flange section in the known prior art into which the tooth element is pressed. In addition, the tooth element also has an essentially L-shaped cross section with a flange section which comes to rest against a stop of the planetary base body and thus fixes the tooth element axially in one direction. In the pressed-in state, the planet carrier base body protrudes to a certain extent in the axial direction beyond the tooth element on the circumference of the recess. This results in a small protrusion that can be caulked to the tooth element, whereby the tooth element is secured axially on the one hand to the stop and on the other hand to the caulking of the protrusion.

Such planetary carriers are often used in automatic transmissions, such as those from DE 10 2005 001 832 A1 are known. There, an automatic transmission, in particular for motor vehicles with at least one planet carrier and at least one adjacent switching element, is presented, the planet carrier having a guide disk at the end and the switching element having a hub and an axially sliding baffle plate arranged in a rotationally fixed manner via driving teeth, the planet carrier also having a rotationally fixed connected to the hub. In that older publication it is proposed that the guide disc have internal drive teeth and the hub external drive teeth and that the guide disc is connected directly to the hub via the drive teeth. There are four segments on the guide disk in which internal drive teeth are formed.

Known planetary gear sets are usually also used in an oil pump drive. Currently, for example, planetary gear sets for oil pumps are offered in which a deep-drawn spline is integrated in a planet carrier cheek designed as a planet carrier half, the two planet carrier halves then being welded, riveted or otherwise connected to one another.

It is the object of the present invention to provide inexpensive connecting means for sufficient torque transmission between a shaft and a planet carrier cheek. The disadvantages known from the prior art are also intended to be eliminated or at least reduced.

This object is achieved in a generic planetary carrier according to the invention in that at least one spacing tooth adjoining the internal toothing segment in the circumferential direction is bent in the axial direction to the shaft in such a way that its free end is prepared to come into contact with a shaft-connected component, preferably the shaft itself so that the shaft is kept at a distance when installed, especially during operation, and the planetary gear set is held in position.

In such a planet carrier, a planet carrier cheek made of sheet metal can be used, the spline of which is produced by cutting or separating (e.g. punching). This spline then interacts with a spline of a shaft and, when installed, is axially supported on one side on a shaft shoulder. In this way it is ensured that the external toothing of the shaft is in sufficient overlap with the internal toothing of the planet carrier cheek. This is particularly of great advantage because the external toothing on the shaft usually has to be produced by cutting and requires an undercut at its outlet opposite the shaft shoulder. The use of an undercut is common and also the consequence of non-cutting production of the spline. The width of the undercut measured in the axial direction corresponds to the width of the sheet metal measured in the axial direction Cheek, in other words the thickness or the stamped spline of a planet carrier cheek. However, the presence of the undercut has always resulted in the problem that as soon as the shaft shoulder comes into contact with the planet carrier cheek, due to the width of the undercut, only part of the internal toothing is in overlap with the external toothing. The undercut then protrudes into the toothed area in an undesired manner. This is now turned off. It is now prevented that when the planet carrier cheek comes axially into supporting contact with the shaft shoulder, the spline of the planet carrier cheek is positioned over the undercut and no longer engages. The fact that the width of the undercut corresponds to the width of the sheet metal of the planet carrier cheek or the punched splines on the planet carrier cheek is now compensated.

With such a configuration, both planet carrier cheeks can be riveted directly in the press in which the sheet metal planet carrier cheeks are manufactured. This can also be implemented in a particularly sensible way if the circular blanks of the two planet carrier cheeks are the same and even if they are different. The two planet carrier cheeks can run next to each other in the press and at the end can be placed on top of each other for riveting by a pivoting process. The fact that the circular diameter of one planetary carrier cheek is larger than the circular diameter of the other planetary carrier cheek due to the deep-drawn plug-in teeth, which means that the planetary carrier cheeks could not run side by side in the press, is now compensated for. The idea that has now been implemented is to punch a spline, which is then only as long as the sheet thickness. The drawn spline now also fulfills the function of an axial spacer or a stop element. With the invention, this stop function can now be provided with conventionally designed punched splines and it is also possible for the customer that the stop is displaceable on the shaft and an undercut is available for the production of the shaft splines. The problem that an undercut designed to approx. 1.7 mm, for example, eliminates almost the entire length / width of the punched spline of the planet carrier cheek, since the planet carrier cheek plate is only approx. 2 mm thick, is eliminated. A solution has thus been found that keeps the planet carrier cheek axially at a distance and even without additional parts.

In other words, the solution presented is that the splines in the planet carrier are only formed in segments, that is, the torque-transmitting teeth are not or are not in engagement over 360 °. Furthermore, those segments that do not have a torque-transmitting effect in the spline are punched out as modified, longer teeth and reshaped in a subsequent press stage, for example. By reshaping the provided elements, an axial stop is produced and the undercut on the shaft, namely in the area of the interface, is bridged.

Advantageous embodiments are claimed in the subclaims and are explained in more detail below.

It is advantageous if there is an end face at the free end of the at least one spacing tooth which is prepared for contact with the shaft-connected component, preferably the shaft itself. A precise axial positioning is the result.

It should also be pointed out that it is possible to design a torque transmission tooth contained in the internal toothing segment and provided for torque transmission as a spacer tooth, i.e. in such a way that part of this spacer tooth is used for torque transmission and a part axially spaced therefrom is used for axial positioning of the shaft .

The forming can be easily integrated into the manufacturing process if the spacing tooth in the unbent state is longer, measured in the radial direction, than at least one torque transmission tooth present in the internal gear segment, preferably longer than all torque transmission teeth used for torque transmission and contained in the internal gear segment.

A compact and weight-reduced embodiment is obtained when the torque transmission teeth and the spacing tooth, measured in the axial direction, have a width that corresponds to the width / thickness of the planet carrier cheek made of sheet metal. The width of the spacer tooth measured in the axial direction in the unbent state is to be used here.

For an even torque transmission it is beneficial if there are three internal tooth segments of the same size, extending over ≤ 120 ° and, for example, each having three torque transmission teeth, the internal tooth segments being separated, for example, by a spacing tooth bent by 90 ° in the direction of the shaft.

The invention enables a planet carrier cheek selected as a planet carrier half with a segmented spline, in particular such a punched spline with a reduced number of teeth. At least one the teeth, the end face of which serves as an axial contact on the support point part, is reshaped.

The invention also relates to a kit of a planetary gear with on the one hand a planet carrier of the type according to the invention and on the other hand a shaft which has external teeth that are in torque-transmitting engagement with the internal teeth of the receptacle in the planet carrier cheek.

If the spacing tooth bridges an undercut between the external toothing and a shaft body, good power transmission and a compact design are guaranteed.

It is expedient if an end face at the free end of the spacing tooth rests (preferably directly) on an end face facing the planet carrier. A high level of operational safety is then given, since the end face provides a sufficiently large system for a shaft shoulder and can absorb large forces.

In this way, a skilful oil pump drive, including the planet carrier according to the invention, can also be implemented.

The invention also relates to a method for producing a plug-in toothing provided for a form fit with an external toothing of a shaft on a planet carrier cheek, for example for use in a planet carrier, as has already been set out according to the invention, for example for an oil pump drive Sheet metal plate, an inner circumferential contour is stamped, which is divided into internal toothing segments separated from one another via, for example, at least one spacing tooth, comprising at least one torque transmission tooth, the torque transmission tooth being measured in the radial direction shorter than the spacing tooth, with the spacing tooth being removed from its radial alignment in a subsequent step is folded over by a bend in the radial direction.

It has proven useful if, in the subsequent step, at least a portion of a plurality of spacing teeth going beyond the inner tip circle of the internal toothing segments is bent pointing in the axial direction of the planet carrier cheek in order to point to a shaft shoulder of the shaft to be coupled. The internal gear segments themselves also have a large number of torque transmission teeth.

In other words, the invention is in the field of planet carriers, these planet carriers having at least one planet carrier cheek in which a spline is present. The aim is to manufacture identical parts, at least in the stamping process. The problem that the planet carrier cheek made of sheet metal is seated on a spline of a shaft produced by machining or punching and is to be supported axially on one side on a shaft shoulder is solved. It is then irrelevant that a cutting or punching production of a spline requires an undercut at its outlet above the shaft shoulder. It is also irrelevant that the (axial) width of the undercut corresponds approximately to the width of the sheet metal of the cheek or the punched spline on the cheek. It can also be implemented that the planet carrier cheek is axially supported on the shaft shoulder. The problem that the spline of the planet carrier cheek is positioned above the undercut and no longer grips / grips is solved. The spline on the cheek is now punched in such a way that on the one hand it has the teeth for the form fit of the spline and on the other hand, when punching, initially with longer, i.e. H. Has (as yet unbent) (spacing) teeth protruding radially inward over the inner tip circle of this spline. In a (simultaneous or subsequent) second method step, at least the portion of the longer (spacing) teeth that goes beyond the tip circle is bent in the axial direction of the planet carrier cheek, which later points to the shaft shoulder. In addition, a device formed at least from the planet carrier cheek and the shaft with such a plug-in toothing is possible. A cleverly manufactured and inexpensive planet carrier with at least one such spline is also possible. This results in the aforementioned advantages.

• 1 eine Planetenträgerwange, wie sie in einem erfindungsgemäßen Planetenträger eingesetzt ist, wobei an die Planetenträgerwange eine Welle angeschlossen ist, und ein Beabstandungszahn mit seiner Stirnfläche in Anlage mit einem Wellenabsatz der Welle steht,
• 2 eine perspektivische Darstellung nur jener Planetenträgerwange aus dem Ölpumpenantriebsausführungsbeispiel der 1 und
• 3 eine Längsschnittdarstellung nur der Planetenträgerwange, entlang der Linie III aus 2, vergleichbar zu der Längsschnittdarstellung aus 1.

The invention is explained in more detail below with the aid of a drawing. Show it:

• 1 a planet carrier cheek, as used in a planet carrier according to the invention, a shaft being connected to the planet carrier cheek, and a spacing tooth with its end face in contact with a shaft shoulder of the shaft,
• 2 a perspective view of only that planet carrier cheek from the oil pump drive embodiment of FIG 1 and
• 3 a longitudinal sectional view of only the planet carrier cheek, along the line III 2 , comparable to the longitudinal section 1 .

The figures are only of a schematic nature and are only used for understanding the invention. The same elements are provided with the same reference symbols.

In 1 is a planet carrier according to the invention 1 shown for a motor vehicle use. The planet carrier 1 can be installed within a drive train of the motor vehicle or can be used in the context of an oil pump gear set.

The planet carrier 1 has a planet carrier cheek 2 on. The planet carrier cheek 2 is manufactured without cutting from a piece of sheet metal. In particular, it is punched. She has a recording in the center 3 for a wave 4th . The planet carrier cheek 2 has an internal toothing designed as a spline 5 . The internal gearing 5 is used to transmit torque between the planet carrier 1 and the wave 4th intended. The internal gearing 5 extends segment-like over less than 360 ° of the circumference of the recording 3 . It forms internal toothing segments that are separate from one another 6th out. These internal gear segments 6th , of which there are exactly three internal toothing segments extending over the same angular range 6th are particularly good at 2 to recognize.

Coming back to 1 it should be pointed out that there is at least one spacing tooth 7th gives. In the present embodiment, there are three spacing teeth 7th . These spacing teeth 7th are teeth that are reshaped when in operation. The spacing teeth 7th are not used for torque transmission in the present exemplary embodiment. However, this is conceivable in a further embodiment.

The three spacing teeth 7th seen in the circumferential direction, separate the internal toothing segments from one another. But they are also used for axial spacing and positioning of the shaft 4th used. So are their end faces 8th at free ends 9 the spacing teeth 7th on one end face of a shaft shoulder 11 the wave 4th directly to. Each spacing tooth 7th bridges the width of an undercut measured in the axial direction 12th .

An external toothing 13th the wave 4th is therefore completely in meshing engagement with the internal teeth 5 .

As with the embodiment of the 2 The spacing tooth is clearly visible 7th offset radially further outwards than one with the reference number 14th referenced inner head circle 14th the internal gearing 5 .

In the 1 to 3 is the axial direction with the reference number 15th , the radial direction with the reference number 16 and the circumferential direction with the reference symbol 17th marked.

In the 3 is the axial protrusion of the originally radially inward over the inner tip circle 14th protruding portion of the spacer tooth after bending over that radial plane in which the planet carrier cheek is arranged, in the direction of the shaft 4th , especially in the direction of the shaft shoulder 11 , visualized. The wave heel 11 can also be referred to as a shaft body.

There, as well as in 2 , it can be seen that each internal gear segment 6th has three teeth, which are provided for torque transmission, so that torque transmission teeth 18th available. During the production of the planet carrier cheek 2 it is conceivable that in a first step both the spacing teeth 7th , as well as the torque transmission teeth 18th be punched out and then subsequently a folding or bending of the spacer tooth 7th he follows. This can take place in a stepped tool, for example, or with different tools. A band-like movement of the plate-like planet carrier cheek 2 is possible and conceivable.

The internal toothing is also conceivable with a skilful tool design 5 and the spacing teeth 7th at the same time, with integrated bending of the spacing teeth 7th , to accomplish. A sequential production, e.g. first of the torque transmission teeth 18th and / or the spacing teeth 7th , and then creating the curvature of the spacing teeth 7th , however, is also possible.

List of reference symbols

1

Planet carrier

2

Planet carrier cheek

3

admission

4th

wave

5

Internal gearing

6th

Internal gear segment

7th

Spacing tooth

8th

Face

9

free end of the spacer tooth

10

Front side

11

Shaft shoulder / shaft body

12th

Freeway

13th

External gearing

14th

Inner head circle

15th

Axial direction

16

Radial direction

17th

Circumferential direction

18th

Torque transmission tooth

QUOTES INCLUDED IN THE DESCRIPTION

This list of the documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• DE 102007003676 A1 [0002]
• DE 102005001832 A1 [0004]

Claims (10)

Planet carrier (1) for use in a motor vehicle, with a planet carrier cheek (2) which has internal toothing (5) for torque transmission between the planet carrier (1) and the shaft (4) in a receptacle (3) for a shaft (4), wherein the internal toothing (5) extends segment-like over only part of the circumference of the receptacle (3) and thereby forms at least one internal toothing segment (6), characterized in that at least one spacing tooth (7) adjoining the internal toothing segment (5) in the circumferential direction so is bent in the axial direction to the shaft (4) that its free end (9) is prepared to come into contact with a shaft-connected component in order to keep the shaft (4) at a distance in the operating state. Planet carrier (1) after Claim 1 , characterized in that at the free end (9) there is an end face (8) which is prepared for contact with the shaft-connected component. Planet carrier (1) after Claim 1 , characterized in that the spacer tooth (7) in the unbent state, measured in the radial direction, is longer than at least one torque transmission tooth (18) present in the at least one internal tooth segment (6). Planet carrier (1) after Claim 3 , characterized in that the at least one torque transmission tooth (18) and the at least one spacing tooth (7), measured in the axial direction, have a width which corresponds to the width of the planet carrier cheek (2) made of sheet metal. Planet carrier (1) after Claim 1 , characterized in that there are three internal toothing segments (6) of equal size, extending over ≤ 120 °, the internal toothing segments (6) each being separated by a spacing tooth (7) bent by 90 ° in the direction of the shaft (4). Kit consisting of a planetary gear with on the one hand a planet carrier (1) according to one of the preceding claims and on the other hand a shaft (4) which has an external toothing (13) which is in torque-transmitting engagement with the internal toothing (5) of the receptacle (3) in the planet carrier cheek (2) stands. Kit according to Claim 6 , characterized in that the at least one spacer tooth (7) bridges an undercut (12) between the external toothing (13) and a shaft base body (11). Planet carrier (1) after Claim 6 , characterized in that an end face (8) at the free end (9) of the spacer tooth (7) rests against an end face (10) of the shaft (4) facing the planet carrier (1). A method for producing a plug-in toothing provided for a form fit with an external toothing (13) of a shaft (4) on a planet carrier cheek (2), an inner circumferential contour being punched in the area of a receptacle (3) of a sheet metal plate, which is divided into at least one spacing tooth (7 ) separate internal toothing segments (6), comprising at least one torque transmission tooth (18), the at least one torque transmission tooth (18) being shorter than the spacing tooth (7) measured in the radial direction, the spacing tooth (7) moving out of its radial direction (16 ) is folded over by a bend in the axial direction (15). Procedure according to Claim 9 , characterized in that at least one portion of a plurality of spacing teeth (7) that goes beyond the inner tip circle (14) of the inner toothing segments (6) is bent in the axial direction (15) of the planet carrier cheek (2) in order to point to a shaft shoulder (11) the shaft to be coupled (4).

Images