DE102014214159A1 - Device and method for mounting steering shafts on steering input shafts - Google Patents

Abstract

Centering device for the alignment of a steering shaft to a steering gear input shaft during assembly. The centering device has a base body with a first axis, which is arranged against rotation on an end piece of a steering gear input shaft coaxial and by positive engagement. The centering device has a first form-fitting section which is designed to engage in a form-fitting manner in a profile of the end piece of the steering gear input shaft and has a second form-fitting section which can be inserted in a form-fitting manner into a recess of a recess of a steering shaft. The second form-fitting section is designed to enable or block insertion of the second form-fitting section into the recess as a function of the orientation of the centering device relative to the recess.

Description

The invention relates to a device and a method for mounting steering shafts on steering gear input shafts, in particular on steering gear input shafts of motor vehicles.

In the manufacture of automobiles, a variety of assembly steps are required. Many of these assembly steps are carried out as part of a flow production, so that only one predetermined time window is available as the cycle time for each of these assembly steps. To ensure a smooth operation of the assembly line, it is necessary to comply with the specified cycle time during assembly. Exceeding the predetermined cycle times can in the worst case lead to a temporary stoppage of an assembly line, since follow-up processes are often only feasible after completion of the offending process.

To reduce manufacturing costs cycle times are to be selected that allow a correct installation under realistic conditions, which requires no reworking. Rework within a cycle, z. B. due to a wrong performed assembly process, i.d.R. to a deviation from the specified cycle time and thus to a slowing down of the entire assembly process. Therefore, reasons that can lead to reworking are, as far as possible, already eliminated during assembly planning. In particular, system-related reasons, which lead to regularly recurring rework, must be eliminated, if possible without making individual assembly processes much more time-consuming.

One assembly step, which often leads to assembly errors, is the assembly of prefabricated assemblies when accurate positioning and alignment of the assemblies with each other during assembly is required, especially when the parts to be joined have relatively large dimensions or weight or unsuitable shapes. If such a positioning or alignment is not correct, this can lead to a wrong assembly of the modules. In particular, assemblies with a large mass or difficult to access assemblies or mounting locations of the modules complicate a correct positioning or alignment of the modules.

The installation of steering shafts on steering input shafts here represents a particular challenge. Steering drive shafts have an internally toothed receptacle with a receiving longitudinal axis, which is often fork-shaped and which is to be mounted on an external toothing of an end piece of a steering gear input shaft with a tail longitudinal axis. In conventional assembly method, the recording of the steering shaft is first brought to the end of the steering gear input shaft and aligned with it such that a receiving longitudinal axis with the tail longitudinal axis is located on a common longitudinal axis and that the respective teeth are aligned correctly. Subsequently, the receiving and tail are joined together by an axial relative movement. It often happens that when joining a relative rotation of the receiving and tail takes place about the longitudinal axis, so that the teeth of the receiving and tail are no longer aligned correctly with each other. If this relative rotation is at least about one pitch of the toothing, there is a risk that the teeth of the receiving and the end piece during the assembly rotatably offset engage each other. Thus, a mating of the components is not possible. In this case, the correct position in the direction of rotation between the components must be found. The assembly takes place in the footwell of the vehicle. This is difficult to access and conditionally visible. To feel and find the correct position (tooth to tooth), a rotation of the PTO shaft is required. With the C-EPS (steering column with electric motor for steering assistance), the torque of the steering shaft is high. Turning the PTO shaft with hand force and feeling the small teeth to find the correct position is difficult. These conditions make the joining of the components considerably more difficult. As a result, the predetermined for the Zusammenfügeprozess of steering shaft and steering input shaft clock cycle i.d.R. exceeded, which often results in a significant increase in assembly costs.

Therefore, it is the object of the present invention to provide an apparatus and a method for mounting steering shafts on steering input shafts, which ensure a safe mounting of steering shafts on steering input shafts, so that the steering shaft is correctly aligned after the assembly process to the steering gear input shaft and the parts not misfitted together can be.

The object is achieved by a centering device according to claim 1, a steering gear according to claim 9 and a method according to claim 10. The dependent claims 2 to 8 represent advantageous embodiments of the invention.

Accordingly, the object is achieved by a centering device for aligning a steering shaft to a steering gear input shaft during assembly, wherein the centering device has a main body with a first axis coaxial with an end piece of a steering gear input shaft and by positive engagement can be arranged against rotation. The main body has a first positive engagement portion and a second positive engagement portion, wherein the first positive engagement portion is formed to engage positively in a profile of the tail of the steering input shaft. The second form-fitting section can be inserted in a form-fitting manner into a recess of a recess of a steering shaft, wherein the recess has a substantially round cross-section and an internal toothing with a pitch. The second form-fitting section is designed to enable or block insertion of the second form-fitting section into the recess as a function of the orientation of the centering device relative to the recess. The centering device can be inserted into the recess when the centering device is arranged coaxially to the recess and has a specific rotational orientation to the recess. In this rotational alignment of the centering device to the steering shaft arranged on the centering steering gear input shaft to the steering shaft is aligned according to assembly.

The main body of the centering device is adapted to a cross section of the end piece and is preferably formed either disc-shaped or annular, wherein the base body must be formed, to be introduced together with the end piece into the recess. After assembly of steering shaft and steering input shaft, the main body may remain on the tail and is therefore designed such that it can not be detached from its seat in this state. The centering device is preferably made of a lightweight material, such. B. plastic.

A division of a toothing in the context of the invention is the distance of a point of a tooth to a corresponding point of an adjacent tooth. The pitch of the internal toothing of the recess or the external toothing of the end piece is constant over the entire circumference.

The centering device according to the invention is an assembly aid which is coaxially pushed onto an end piece of a conventional steering input shaft and which supports a correct mounting of a steering shaft with a steering input shaft. In this case, the centering device allows an assembly of an end piece of the steering gear input shaft with a recess of the steering shaft at a certain orientation of tail and recess, which is also referred to as montagegemäße orientation. Over a range of relative rotation of tail to recess from the assembly according to the alignment about the common axis, which corresponds to a pitch of a teeth of tail and recess or greater, an assembly of tail and recess is blocked by the centering device. Thus, by the centering device according to the invention a faulty Anschnäbeln the teeth of the steering shaft and steering input shaft prevents and thus avoided reworking and favors compliance with the predetermined cycle times.

By the first positive connection portion, the centering device can be arranged positively against rotation on the end piece. It is in one embodiment, for. Example, possible, the centering device at a distance of a pitch of an external toothing of the tail relative to the tail rotated about the common axis to position on the tail. In order for this embodiment of the centering can ensure correct alignment of steering shaft and steering input shaft in the assembly of these components, a correct alignment of the centering device to the end of the steering gear input shaft is required before pushing. This alignment is preferably carried out before the provision of the steering gear at the assembly station of the steering shaft, z. B. at the manufacturer of the steering gear. The correct position of the centering device to the tail may possibly be controlled by the worker before assembling the steering shaft and steering input shaft.

Preferably, the second form-fitting portion and the recess are formed such that the centering device can be arranged in a form-fitting manner in only one relative position relative to the recess.

In a preferred embodiment of the invention, the second form-fitting section has a width which corresponds at least to the pitch of the internal toothing of the recess or is larger. As a result, the alignment of the end piece and the recess is facilitated since a width of the recess of the receptacle corresponds to the width of the second form-fitting portion and thus is more easily distinguishable from the worker by the internal toothing. The second form-fitting portion thus has a width, is blocked by the engagement of the second form-fitting portion between two adjacent teeth of the internal teeth of the recess when the steering gear input shaft is arranged with arranged thereon centering device to the steering shaft is not aligned.

Preferably, the first interlocking portion and the profile of the tail have a shape by which engagement of the first interlocking portion in the profile of the tail is blocked depending on the orientation of the centering device to the tail. This will be a correct Orientation of the centering device to the steering gear input shaft when mounting on this easier. For this it is necessary that the steering gear input shaft has a corresponding profile, the z. B. on the front z. B. as a depression, z. B. as a groove is formed.

It can be provided that the recess of the receptacle is formed as a centering, which is widened towards the centering, in which the second positive connection portion is thus also inserted when the centering device is rotated relative to the recess about the common axis, wherein when pushing together Receiving and tail of the second form-fitting portion along a side wall of the centering channel is slidable, so that while recording and tail are aligned correctly with each other before the internal teeth with the external teeth engages. As a result, a self-centering of steering shaft and steering input shaft is achieved and facilitates the assembly.

Preferably, the first form-fitting portion and the profile are formed such that an assembly is not blocked only with a correct orientation of the centering device to the steering gear input shaft. It is essential that an assembly of centering device and steering gear input shaft is blocked when the relative orientation slightly deviates from the correct orientation, for. At least +/- 5 °, preferably at least +/- 10 °, more preferably at least +/- 25 °.

In an advantageous embodiment of the invention, the first positive connection section has at least one first lug which extends parallel to the first axis of the main body away from the body and engages positively in the outer toothing of the end piece of a steering gear input shaft when the centering device is placed coaxially on the end region. Such a first nose ensures a positive rotation of the centering device on the tail with minimal material costs.

Preferably, the first positive engagement portion has a plurality of first lugs which extend parallel to the first axis of the body away from the body and engage positively in the outer toothing of the end of a steering input shaft, when the centering device is placed on the tail coaxially. As a result, the first positive locking section acquires greater stability, and the anti-rotation of the centering device is increased.

It is preferred that at least two adjacent first lugs are arranged side by side so that the at least two adjacent first lugs engage in grooves of the toothing, which are adjacent to one another, when the centering device is placed on the tail. The first lugs thus have a pitch corresponding to the pitch of the outer teeth of the tail. Such a centering device is particularly compact and stable.

More preferably, the second form-fitting portion is formed as a second nose, which extends parallel to the first axis of the body from the body away and positively engages in a recess of the recess of a steering shaft when the centering device is inserted coaxially into the recess. Such a second nose ensures a positive rotation of the centering device in the recess with minimal material costs.

Preferably, the first nose and the second nose form a common nose. The common nose extends over one side of the centering device. As a result, the stability of the centering device is further improved.

Furthermore, the object is achieved by a steering gear having a centering device according to the invention. The centering device is preferably arranged on the end piece of the steering gear input shaft and aligned therewith.

• – Anordnen einer erfindungsgemäßen Zentriervorrichtung an einem Endstück einer Lenkgetriebeeingangswelle, wobei die an dem Endstück angeordnete Zentriervorrichtung eine vorbestimmte Orientierung zum Endstück aufweist;
• – Heranführen des Endstücks mit der Zentriervorrichtung an eine Aussparung einer Ausnehmung einer Lenkungswelle;
• – Ausrichten von Endstück und Ausnehmung zueinander;
• – Zusammenschieben von Endstück und Ausnehmung.

In addition, the object is achieved by methods for mounting steering shafts on steering input shafts, which is characterized by the following steps:

• Arranging a centering device according to the invention on an end piece of a steering gear input shaft, wherein the centering device arranged on the end piece has a predetermined orientation to the end piece;
• - Preceding the tail with the centering device to a recess of a recess of a steering shaft;
• - Aligning tail and recess to each other;
• - Pushing together of tail and recess.

The alignment of the end piece and recess takes place here via the second form-fitting section of the centering device and the recess of the recess. For this purpose, the steering shaft and end portion of the steering gear input shaft are initially aligned substantially coaxially and substantially in accordance with assembly to each other. Subsequently, the second form-fitting portion with the recess are brought into engagement with each other and steering shaft and steering gear input shaft thereby aligned according to assembly to each other. When pushed together, the second form-fitting section slides in the recess of the steering shaft and thus prevents relative rotation of the steering shaft and tail. Upon further collapse, the internal teeth and external teeth are intended to engage with each other as intended. The centering device can remain on the end piece.

In the following, the centering device according to the invention will be explained in more detail with reference to drawings. In the drawings shows:

1 a schematic, perspective view of a first embodiment of a centering device according to the invention,

2 a schematic, perspective view of a second embodiment of a centering device according to the invention,

3 a schematic side view of a connection zone of a steering shaft with a steering input shaft with a second embodiment arranged thereon of a centering device according to the invention from 2 and

4 a schematic plan view of the connection zone 3 ,

In the 1 shown first embodiment of a centering device according to the invention 1a has a hollow cylindrical body 2a with an inner diameter and a first axis 3a on. The main body 2a is on an end portion of a tail 32 a steering gear input shaft 30 attachable and up to an external toothing 34 of the tail 32 pushed. At the base body 2a are a first form-fitting section 4a and a second positive connection section 5a formed, wherein the first positive connection portion 4a at the second positive connection section 5a is held.

The first form-fitting section 4a has a plurality of first noses 6a on, which are elongated and parallel to the first axis 3a from the second positive connection section 5a extend pioneering. In this embodiment, the first positive connection section 4a six first noses 6a on. According to the invention, the number of first noses 6 also be larger or smaller than six. Between two adjacent first noses 6a each is a free space arranged. The first noses 6a are so on the body 2a spread that first nose 6a in the external teeth 34 of the tail 32 engage when the centering device 1a with the first noses 6a to external teeth 34 pointing to the tail 32 is deferred and the main body 2a on the external teeth 34 borders.

The second form-fitting section 5a is as a continuous thickening of the body 2a formed, which extends in the radial direction to the outside. Thus, the centering device 1a a constant inner diameter and in the region of the second form-fitting section 5a a larger outer diameter than in the other areas. The second form-fitting section 5a has a width B and thus extends approximately over a third of the circumference of the body 2a , Edges are preferably rounded or chamfered to facilitate assembly.

In the 2 shown second embodiment of a centering device according to the invention 1b has a cylindrical or disk-shaped base body 2 B with a first axis 3b on. The main body 2 B is on an end portion of a tail 32 a steering gear input shaft 30 placed. At the base body 2 B are a first form-fitting section 4b and a second positive connection section 5b educated.

The first form-fitting section 4b has two parts. A first portion is a cuboid projection 9b formed and extends from an underside of the body 2 B away from this. On the first axis 3b and the body 2 B facing away from the cuboid projection 9b a cylindrical projection 10b on. The cuboid projection 9b is in a corresponding groove 36 of the tail 32 can be used while the cylindrical projection 10b into a corresponding hole in the groove 36 can be used. Thus, the centering device 1b positive and non-rotating on the tail 32 be placed, wherein by the orientation of the groove 36 the orientation of the centering device 1b is predetermined. A second subregion of the first form-fitting section 4b is the first nose 6b formed, the side of the main body 2 B is arranged and parallel to the first axis 3b from the main body 2 B away in the same direction as the cuboid projection 9b and the cylindrical projection 10b extends. The first nose 9b is formed in an external toothing 34 of the tail 32 intervene positively. Alternatively, in this embodiment, also on the first nose 9b be waived because of the cuboidal projection 9b already a certain orientation of centering device 1b and tail 32 is guaranteed.

The second form-fitting section 5b is as a second nose 7b formed, extending from an upper side of the main body 2 B laterally of this and parallel to the first axis 3b from the main body 2 B as well as from the first nose 6b extends away. In this example, the second nose forms 7b with the first nose 6b a common nose 8b ,

3 and 4 show schematically a connection zone one with a steering input shaft 30 assembled steering shaft 24 after assembly. From the steering gear input shaft 30 is in these representations only an end piece 32 recognizable. The tail 32 has an external toothing 34 on, that of an internal toothing 26 a recess 22 a steering shaft 24 equivalent. A second embodiment of the centering device 1b is on a front side of the tail 32 assembled. In one area of the tail 32 , the centering device 1b is adjacent, has the tail 32 no external teeth 34 and a diameter in the recess 22 the steering shaft is insertable. The cuboid projection 9b of the second form-fitting portion 5b the centering device 1b is in a groove 36 the front of the tail 32 taken, so that the centering device 1b against rotation on the tail 32 is arranged.

When installing steering shaft 24 and steering gear input shaft 30 initially the centering device 1b on the front side of the tail 32 secured against rotation. In this case, the cuboid projection engages 9b the steering shaft 24 in the groove 36 of the tail 32 one. An optional first nose 6b device thereby with the external toothing 34 of the tail 32 engaged. Subsequently, steering shaft 24 and steering gear input shaft 30 essentially aligned coaxially with each other. A second nose 7b comes with a recess 20 the steering shaft 24 engaged and the steering gear input shaft 30 with the steering shaft 24 thus aligned with each other. Subsequently, steering shaft 24 and steering gear input shaft 30 in the direction of the first axis 3b collapsible. The centering device 1b is formed such that the centering device 1b in the assembled state of steering shaft 24 and steering gear input shaft 30 on the tail 32 can remain without obstructing a proper operation of the steering.

LIST OF REFERENCE NUMBERS

1a, 1b

 centering

2a, 2b

 body

3a, 3b

 first axis

4a, 4b

 first form-fitting section

5a, 5b

 second form-fitting section

6a, 6b

 first nose

7b

 second nose

8b

 common nose

9b

 cuboid projection

10b

 cylindrical projection

20

 recess

22

 recess

24

 steering shaft

26

 internal gearing

30

 Steering gear input shaft

32

 tail

34

 external teeth

36

 groove

Claims (10)

Centering device ( 1a . 1b ) for the alignment of a steering shaft ( 20 ) to a steering gear input shaft ( 30 ) during assembly, wherein the centering device ( 1a . 1b ) a basic body ( 2a . 2 B ) with a first axis ( 3a . 3b ), which on an end piece ( 32 ) a steering gear input shaft ( 30 ) can be arranged co-axially and by positive locking against rotation, wherein the main body ( 2a . 2 B ) a first form-fitting section ( 4a . 4b ) and a second form-fitting section ( 5a . 5b ), wherein the first form-fitting section ( 4a . 4b ) is formed in a profile of the tail ( 32 ) of the steering gear input shaft ( 30 ) engage positively, wherein the second form-fitting section ( 5a . 5b ) in a recess ( 20 ) a recess ( 22 ) a steering shaft ( 24 ) is positively insertable, wherein the recess ( 22 ) has a substantially round cross-section and an internal toothing ( 26 ) having a pitch, characterized in that the second positive-fit portion ( 5a . 5b ) is formed, an insertion of the second form-fitting portion ( 5a . 5b ) in the recess ( 22 ) depending on the orientation of the centering device ( 1a . 1b ) to the recess ( 22 ) to release or block. Centering device ( 1a ) according to claim 1, characterized in that the second form-fitting section ( 5a ) has a width (B), the at least the pitch of the internal toothing ( 26 ) of the recess ( 22 ) is equal to or greater. Centering device according to claim 1 or 2, characterized in that the first form-fitting section ( 4b ) and the profile of the tail ( 32 ) have a shape by which an intervention of the first form-fitting portion ( 4b ) in the profile of the tail ( 32 ) depending on the orientation of the centering device ( 1a . 1b ) to the tail ( 32 ) is blocked. Centering device ( 1a . 1b ) according to one of the preceding claims, characterized in that the first positive-fit portion ( 4a . 4b ) at least one first nose ( 6a . 6b ), which are parallel to the first axis ( 3a . 3b ) of the basic body ( 2a . 2 B ) from the main body ( 2a . 2 B ) extends away and into the external toothing ( 34 ) of the tail ( 32 ) engages a steering gear input shaft form-fitting when the centering device ( 1a . 1b ) on the tail ( 32 ) is placed coaxially. Centering device ( 1a . 1b ) according to claim 4, characterized in that the first positive-fit portion ( 4a . 4b ) a plurality of first noses ( 6a . 6b ), which are parallel to the first axis ( 3a . 3b ) of the basic body ( 2a . 2 B ) from the main body ( 2a . 2 B ) and into the outer toothing of the end piece ( 32 ) a steering gear input shaft ( 30 ) engage positively when the centering device ( 1a . 1b ) on the tail ( 32 ) is placed coaxially. Centering device ( 1a . 1b ) according to claim 5, characterized in that at least two adjacent first lugs ( 6a . 6b ) are arranged side by side so that the at least two adjacent first noses ( 6a . 6b ) in adjacent grooves of the external toothing ( 34 ) when the centering device ( 1a . 1b ) on the tail ( 32 ) is attached. Centering device ( 1a . 1b ) according to one of the preceding claims, characterized in that the second form-fitting section ( 5a . 5b ) as a second nose ( 7b ) which is parallel to the first axis ( 3a . 3b ) of the basic body ( 2a . 2 B ) extends away from the main body and into a recess ( 20 ) of the recess ( 22 ) a steering shaft ( 24 ) positively engages when the centering device ( 1a . 1b ) in the recess ( 22 ) is used coaxially. Centering device ( 1a . 1b ) according to claim 9, characterized in that the first nose ( 6b ) and the second nose ( 7b ) a common nose ( 8b ) form. Steering gear with a steering input shaft for attachment to a steering shaft, characterized in that the steering gear is a centering device ( 1a . 1b ) according to one of the preceding claims. Method for mounting steering shafts ( 24 ) on steering gear input shafts ( 30 ), characterized by the steps: - arranging a centering device ( 1a . 1b ) according to one of claims 1 to 8 on an end piece ( 32 ) a steering gear input shaft ( 30 ), whereby the at the tail ( 32 ) arranged centering device ( 1a . 1b ) a predetermined orientation to the tail ( 32 ) having; - leading the tail ( 32 ) with the centering device ( 1a . 1b ) to a recess ( 20 ) a recess ( 22 ) a steering shaft ( 24 ); - Aligning tail ( 32 ) and recess ( 22 ) to each other; - pushing together end piece ( 32 ) and recess ( 22 ).

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