DE102008040693A1 - Ball joint for motor vehicles, comprises a pivot pin, whose joint head is rotatably and revolvably arranged in a housing produced through a casting process and is secured by a clasp ring in the housing - Google Patents

Abstract

The ball joint comprises a pivot pin (1), whose joint head (2) is rotatably and revolvably arranged in a housing (3) produced through a casting process and is secured by a clasp ring (4) in the housing. The clasp ring consists of a material having high strength compare to the housing material and has a part of the bearing area of the joint head. The housing is produced under use of a core having a joint head geometry. The housing is produced by direct casting of the joint head pre-hardened on the pivot pin. The housing has a part of the bearing area for bearing the joint head. The ball joint comprises a pivot pin (1), whose joint head (2) is rotatably and revolvably arranged in a housing (3) produced through a casting process and is secured by a clasp ring (4) in the housing. The clasp ring consists of a material having high strength compare to the housing material and has a part of the bearing area of the joint head. The housing is produced under use of a core having a joint head geometry. The housing is produced by direct casting of the joint head pre-hardened on the pivot pin. The housing has a part of the bearing area for bearing the joint head. The bearing area of the housing is formed up to equator of the joint head that is defined through a vertical plane to longitudinal axis of the non-deflecting pivot pin and through the middle point of the joint head. The bearing area in the housing equipped for the joint head has a plastic layer or the clasp ring in the area of the bearing area for the joint ball comprises a plastic layer, where the plastic layer consists of polyether ether ketone. The plastic layer is implemented as polytetrafluoro ethylene coating of the bearing area of the housing and/or the clasp ring. The housing comprises lubricating grooves (11) for the reception of the lubricating agent on the side opposite to the pivot pin. The housing for the connection with further motor vehicle component comprises a connection element forming an integral unit during casting with the housing. An independent claim is included for a method for the production of the ball joint.

Description

The The invention relates to a ball joint and a method for the production such a ball joint.

Ball joints, As used in particular in motor vehicles, have basically a similar structure. To exist they from a pivot pin, the ball joint rotatable and pivotable is stored in a housing. The pivot pin serves on the one hand and the housing on the other hand, two relatively mutually movable components of the motor vehicle with each other connect. Such ball joints are in considerable numbers produced, so that already low simplifications of the manufacturing process bring a significant economic benefit.

To Distinguish are ball joints, which are an immediate storage the joint ball of the pivot pin in a space provided for this purpose Have bearing surface of the housing and ball joints, where between the ball joint and the bearing surface of the housing is inserted a bearing shell. The bearing shells consist mostly of plastics such as polytetrafluoroethylene (PTFE) or polyetheretherketone (PEEK) and must be in these ball joints fulfill several functions. So are the cups on the one hand intended to dampen a vibration To exert effect on the components. Furthermore cause bearing shells between the ball joint and the housing a tolerance compensation as well as partially also lubrication functions, so they are also responsible for the friction reduction are.

In JP 2002-242934 A a ball joint for a motor vehicle and a method for producing a ball joint will be described. First, the joint ball of the pivot pin is partially encapsulated with a plastic material. The thus created and molded onto the ball joint plastic ring is used later in the assembled ball joint as a storage area. The pivot pin with its ball joint and the plastic ring sprayed thereon is first placed in a mold prepared for this purpose in order to subsequently cast the liquid housing material into the mold. The joint ball is thus used in this solution when casting the housing as a core and cast directly. In this way, the housing for the ball joint can be generated. According to the disclosure of the publication, the plastic layer which surrounds the ball joint, to be cured during the casting process by the resulting heat from the liquid housing material. By introducing a plastic layer between the ball joint and the housing of the ball joint, the bearing properties of the pivot pin can be improved.

Another solution comes from the JP 62-288715 A out. Here, a ball joint is described, the ball joint is mounted directly, that is, without a bearing shell in a housing produced by a casting process. For this purpose, the document discloses a manufacturing method for producing such a ball joint, which consists in that first generates the pivot pin and then used in a prepared form for generating the housing. In this case, the joint ball protrudes into the receiving space provided for this purpose later in the housing. The ball joint itself thus also serves as a core in the manufacture of the housing. Subsequently, the mold is filled with the liquid housing material. To produce the mobility of the overmolded joint ball, it is necessary in a final method step to apply an external force to the pivot pin.

Of the Invention is based on the object, a ball joint for to provide a motor vehicle that is easy to manufacture and also has optimal storage properties.

Solved This task is combined with the characteristics of the independent Claims.

Further Embodiments of the invention are in the respectively subsequent Subclaims reproduced.

One Inventive ball joint for a motor vehicle Therefore, has a pivot pin, the ball joint rotating and pivotable in a total produced by a casting process Housed and secured by a locking ring in the Housing secured is added. There is the locking ring from a higher strength compared to the housing material Material. The locking ring also has a part of the bearing surface the joint ball on.

These allow special features according to the invention a manufacturing technology simplified production of the ball joint, Such ball joints are characterized by a long service life. It could also be found that in solutions Of the prior art often known as disadvantageous danger of Relaxation of the joint components in the course of use in the motor vehicle and the risk of unwanted separation of the pivot pin from the housing by exceeding the pull-out force, So one on the pivot pin in the direction of the housing opening acting force, which can be avoided by the invention.

There the locking ring of one compared to the housing material is made of higher strength material, there is an advantage during assembly of the ball joint according to the invention in that a post-machining of the by casting produced housing no longer needs to be done. Rather, it can the locking ring directly into a case on the housing provided receiving trough be pressed. Also by this measure can the manufacture and assembly of the invention Ball joint can be simplified to a considerable extent.

For the production of a ball joint according to the invention There are two alternatives. On the one hand is according to one first variant of the invention provides that the housing using a core having the ball geometry will be produced. In this embodiment is therefore not the pivot pin or its ball joint directly overmoulded to thereby make the case, but a separate core is used for this purpose. this has the advantage that the pivot pin no preparation for must be subjected to the casting process. In addition, the core reusable.

A Another alternative is that the housing through Immediately encapsulating the existing on the pivot pin Joint ball is made. This procedure known per se becomes used according to the invention to an almost tolerance neutral To allow production of the ball joint. The contour the joint ball, the pivot pin and the corresponding thereto Storage space in the housing are optimally placed on each other Voted. It needs no special mention that in this production variant, in particular the ball joint of a must be subjected to prepared treatment in order to avoid that the liquid housing material with the Surface of the ball joint cohesively connects. For this purpose, there is a suitable measure, for example in the coating of the joint ball surface before the casting process.

A further solution also provides that the housing at least part of the bearing surface forms or has for the storage of the joint ball. In this sense, a preferred variant is seen in that the ball joint is mounted directly in the housing. Is in the housing an additional storage layer provided, this is to be understood that the housing the bearing surface for the bearing of the joint ball having.

One very decisive advantage in the production of an inventive Ball joint is, however, to be seen in that the bearing surface of the housing only to the equator of the ball joint is formed so that this bearing surface is a hemisphere. This equator is defined by a perpendicular to the longitudinal center axis the undeflected pivot pin and the center of the Joint ball going, imaginary plane defined in its arrangement. Such a bearing of the joint ball of the pivot pin in the housing has several advantages. On the one hand can be with the embodiment in which the ball joint directly is encapsulated by the housing material, the ball joint pouring out of the case without difficulty solve and is therefore stored with low friction and tolerance neutral.

One Another advantage can be seen from the assembled Explain ball joint. Here can namely the Angular range around which the pivot pin pivots in the housing is stored, can be chosen arbitrarily large, because he is not limited by the case. The achievable Angle range depends only on the used Closing components of the ball joint. A large swivel angle range has decisive advantages when installing the ball joint in one Motor vehicle.

Ultimately There is still the advantage that a ball joint according to the invention easy to assemble.

A Another embodiment of the invention is that the for the joint ball provided bearing surface in the housing has a plastic layer. Likewise, the lock ring in the area of the bearing surface for the joint ball have such a plastic layer. As a plastic layer can Preferably materials such as PEEK are used. About that however, a plastic layer is also possible as the PTFE coating of the bearing surface of the housing and / or the lock ring is executed. The vote the suitable plastic layer material is aimed according to the friction values to be achieved and the desired Bearing properties of the pivot pin within the ball joint.

Through a plastic layer manufacturing tolerances of the locking ring and / or the housing can be compensated. In addition, such a plastic coating allows, in particular, when it is provided on the closure ring, a centering of the pivot pin to be inserted into the housing. Since the plastic layer can have any geometry, which is made possible in particular by spraying, undercuts can also be achieved here. These undercuts lead to a secure and permanently strong connection between the plastic layer and the locking ring or Lagerflä surface of the housing is reached. The undercut is particularly suitable for injection molding of the plastic layer on the closure ring.

A Another particularly advantageous possibility is to that the plastic layer on both the locking ring and vapor-deposited on the bearing surface of the housing or is sprayed on. This can with a low material input a optimal storage of the joint ball can be achieved.

According to one Another embodiment of the invention, the housing at least on the opposite side of the pivot pin Have lubrication grooves for receiving lubricant. These lubrication grooves or a lubricant reservoir present in this area are used to introduce a lubricant. By providing Lubricant within the ball joint may be due to reduced friction the life of the ball joint can be improved overall. The Lubricant is distributed by the movement of the pivot pin relative to the housing between the bearing surface of the Housing or the locking ring and the corresponding Surface of the joint ball. The lubrication grooves and an optionally be provided lubricant reservoir in the casting process of the housing molded directly into the housing and can protrude into the storage areas.

in the Toward the endeavor, the ball joint according to the invention in total to simplify and the manufacturing steps required for its production In addition, it is suggested that the housing for connection with other motor vehicle components at least one when casting with the housing one having integral unit forming connection element. This connection element Consequently, during the casting process directly into the mold used for the production of the housing and is connected to the housing during casting. a later one Assembly is unnecessary so that the ball joint in its manufacture is simplified. Conceivable here are different Designs of connection elements. So can for example a connecting rod in the housing production with poured become. In addition, however, it is also conceivable, for example a core with a negative thread to create a connection thread to insert on the housing. This core will after the casting process removed, leaving the case already with a usable one Thread is equipped. Other machining operations can thus be limited to a small extent or completely eliminated.

• – Einsetzen des Gelenkzapfens in eine hierfür vorbereitete Gusswerkzeugform,
• – Befüllen des Kammerhohlraumes mit dem flüssigen Gehäusewerkstoff,
• – Abkühlung und Aushärtung des Gehäuses,
• – Entnahme des vorgefertigten Kugelgelenkes aus der Gusswerkzeugform,
• – Einsetzen des Verschlussringes in die hierfür vorhandene Aufnahmemulde des Gehäuses,
• – Umformung des Umformabschnittes zur Fixierung der Kugelgelenk-Bauteile.

A first method according to the invention for producing a ball joint has the following method steps:

• Inserting the pivot pin into a mold tool prepared therefor,
• Filling the chamber cavity with the liquid housing material,
• Cooling and curing of the housing,
• Removal of the prefabricated ball joint from the casting mold,
• Inserting the locking ring into the receiving recess of the housing provided therefor,
• - Forming the Umformabschnittes for fixing the ball joint components.

at This method is, as already mentioned in the context was explained with the ball joint, the ball joint of the Hinge pin directly through the liquefied housing material molded.

• – Einsetzen eines die Geometrie der Gelenkkugel aufweisenden Kerns in eine hierfür vorbereitete Gusswerkzeugform,
• – Befüllen des Kammerhohlraumes mit dem flüssigen Gehäusewerkstoff,
• – Abkühlung und Aushärtung des Gehäuses,
• – Entnahme des vorgefertigten Kugelgelenkes aus der Gusswerkzeugform,
• – Entfernen des Kugelkerns und anschließendes Einsetzen der Gelenkkugel des Gelenkzapfens in die Lagerfläche des Gehäuses,
• – Einsetzen des Verschlussringes in die hierfür vorhandene Aufnahmemulde des Gehäuses,
• – Umformung des Umformabschnittes zur Fixierung der Kugelgelenkbauteile.

Alternatively, another method for producing a ball and socket joint according to the invention is characterized by the following method steps:

• Inserting a core having the geometry of the joint ball into a casting mold prepared for this purpose,
• Filling the chamber cavity with the liquid housing material,
• Cooling and curing of the housing,
• Removal of the prefabricated ball joint from the casting mold,
• Removing the ball core and then inserting the ball joint of the pivot pin in the bearing surface of the housing,
• Inserting the locking ring into the receiving recess of the housing provided therefor,
• - Forming the Umformabschnittes for fixing the ball joint components.

The second method for producing a novel Ball joint differs from that previously described in that instead of the ball joint a core with the geometry the ball joint is overmolded. This reusable core needs removed from the housing after the casting process and be replaced by the pivot pin to be used. That last said method has compared to the former the Advantage that the bearing surface for the ball joint in the Housing after removal of the core of a final Processing may be subjected, if desired is. For example, here in the geometry enlarged core can be used to subsequently the coating of the bearing surface of the housing to provide with a plastic layer, in which then the joint ball of the Pivot can be used.

According to an embodiment of the presented method, before pouring the Ge Housing material in the casting mold a connection element can be used. This connection element later serves to connect the ball joint to the motor vehicle.

As Beyond that, beyond that be provided that before assembling the ball joint components the bearing surface of the housing and / or the bearing surface of the closure ring is coated with a plastic layer. Accordingly, according to another embodiment the method proposed that the plastic layer on the To be coated surface sprayed or evaporated becomes.

Around the friction values of a ball joint according to the invention in the manufacture or assembly of the ball joint To optimize, an embodiment of the procedure is that during the assembly of the ball joint components, a pressing force is exercised on the locking ring and with increasing Pressing force required for the movement of the pivot pin torques measured on the pivot pin, after reaching a predetermined, defined torque formed a forming section of the housing and thus the housing is closed. Thus, that remains last determined torque for the movement of the pivot pin obtained relative to the housing.

The Ball joints according to the invention are accordingly by a high precision, a long service life at simpler production-technical manufacturability.

Some preferred embodiments of the invention are hereafter explained in more detail with reference to the accompanying drawings. The embodiments shown are not limiting on the variants shown, but only serve the Explanation of the principle of the invention. Here are the same or similar components with the same reference numerals.

Around illustrate the operation of the invention To be able to, are in the figures only greatly simplified schematic representations shown, in which on the components not essential to the invention was waived. However, this does not mean that such components not in a solution according to the invention available.

In The figures are exemplified three preferred embodiments of the invention explained, to which the invention, however is not restricted.

It demonstrate:

1 a section through a first embodiment of a ball joint according to the invention,

2 : a second variant of a ball joint according to the invention in section,

3 a third embodiment variant of a ball joint according to the invention in section,

4 : A schematically simplified view of the production of a housing by a casting process in section.

That in the 1 shown ball joint has a pivot pin 1 up, over a joint ball 2 rotatable and pivotable in a housing 3 is stored. The pivot pin 1 is shown in the illustration in an undeflected position. Its longitudinal center axis 7 becomes perpendicular and through the center of the joint ball 2 running from a plane cut through the equator 6 the joint ball runs and thus defines this. It is indicative in the illustrated embodiment of a ball joint according to the invention that one in the housing 3 existing storage area 5 only up to the equator 6 the joint ball 2 reaches and thus the lower part of the joint ball 2 that is, the part of the joint ball that is the pivot pin 1 is arranged opposite, absorbs. For fixing the pivot pin 1 in the case 3 serves a locking ring 4 , In contrast to the housing material is the locking ring 4 made of a higher-strength material. Thus, the housing material may preferably be aluminum and the closure ring 4 to act a steel material. The lock ring 4 at the same time forms part of the bearing surface for the bearing of the joint ball 2 , On the pivot 1 opposite side are below the ball joint 2 in the case 3 an unspecified lubricant reservoir and lubrication grooves 11 in the housing or the storage area 5 of the housing 3 are incorporated to move the pivot pin 1 relative to the housing 3 to ensure a supply of contact surfaces with lubricant. The housing 3 also has a laterally projecting shaft into which a cavity 13 is incorporated for a connection element. To close the housing 3 and thus for fixing the pivot pin 1 inside the case 3 serves a forming section 14 , which can be formed, for example, by a rolling process and so the locking ring 4 in the case 3 fixed. The housing 3 also has a sealing bellows receiving groove 15 on, in the later, in the assembled ball joint, an edge region of a sealing bellows is inserted. A sealing bellows is for reasons of simplicity in the in 1 shown ball joint not shown.

A second embodiment of a ball joint according to the invention is in the 2 shown. The ball joint in 2 is almost identical to the already in connection with 1 described ball joint executed. Again, this is a pivot pin 1 rotatable and pivotable in a housing 3 stored, what he a ball joint 2 having. Essential in the ball joint in 2 is that on the lock ring 4 a plastic layer 10 is provided. The plastic layer 10 is on a surface of the lock ring 4 applied and forms a bearing surface for the storage of the joint ball 2 , Due to the special geometric design of the locking ring 4 as he is in the 2 can be achieved, that the plastic layer 10 forms a kind of undercut. This has the consequence that a secure fixation of the plastic layer 10 between joint ball 2 and lock ring 4 becomes possible. In addition, this design of the plastic layer acts 10 Tolerances balancing on the components to be joined together. The joint ball 2 will also be in their position in the housing 3 fixed and held in position.

A third embodiment of a ball joint according to the invention goes from the illustration in 3 out. Also, this ball joint has substantially the same features as those already in connection with the 1 and 2 explained ball joints. A difference to the other variants is present in that in the housing 3 a storage area 5 exists, consisting of a first plastic layer 8th consists. Furthermore, the storage area 9 of the lock ring 4 another plastic layer 10 on. Together, the plastic layers form 8th and 10 a bearing shell for receiving the joint ball 2 inside the case 3 , The plastic layer 8th in the case 3 Can be sprayed after casting the case 3 be generated. In contrast, the locking ring 4 be made as a completed component in a prefabrication.

In the 4 becomes a cast tool shape 16 Partially shown how to make a case 3 can be used for a ball joint according to the invention. The cast tool shape 16 has a receptacle for the pivot pin 1 on, in the presentation of the 4 is inserted into the recording form. Furthermore, a connection element 12 in the case 3 inserted, so when casting the case 3 this connection element 12 can be integrated directly into the housing. The joint ball 2 juts up to its equator 6 in a chamber cavity 18 in, as a negative mold to the housing to be generated 3 is executed. In addition, the chamber cavity points 18 for generating the housing 3 a negative form 19 of the forming section. Via an injection channel 17 For example, the liquefied housing material may be directed in the direction of arrow A into the chamber cavity 18 be introduced.

1

pivot pin

2

joint ball

3

casing

4

lock ring

5

storage area of the housing

6

equator

7

Longitudinal central axis

8th

Plastic layer in the case

9

storage area of the lock ring

10

Plastic layer at the lock ring

11

lubrication

12

connecting element

13

cavity for the connection element

14

forming section

15

Dichtungsbalgaufnahmenut

16

Casting mold

17

Injection channel

18

chamber cavity

19

negative form the forming section

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - JP 2002-242934 A [0004]
• JP 62-288715 A [0005]

Claims (17)

Ball joint for a motor vehicle with a pivot pin ( 1 ), whose ball ( 2 ) rotatable and pivotable in an overall produced by a casting process housing ( 3 ) and by a locking ring ( 4 ) in the housing ( 3 ), wherein the locking ring ( 4 ) consists of a material which is of a higher strength compared to the housing material and a part of the bearing surface of the joint ball ( 2 ) having. Ball joint according to claim 1, characterized in that the housing ( 3 ) is made using a core having the joint ball geometry. Ball joint according to claim 1, characterized in that the housing ( 3 ) by directly encapsulating the on the pivot pin ( 1 ) existing ball joint ( 2 ) is made. Ball joint according to one of the preceding claims, characterized in that the housing ( 3 ) at least part of the storage area ( 5 ) for the storage of the joint ball ( 2 ) forms or has. Ball joint according to claim 4, characterized in that the bearing surface ( 5 ) of the housing ( 3 ) to the equator ( 6 ) of the joint ball ( 2 ) formed by a perpendicular to the longitudinal center axis ( 7 ) of the undeflected pivot pin ( 1 ) and through the center of the ball ( 2 ), imaginary plane is defined. Ball joint according to claim 4 or 5, characterized in that for the joint ball ( 2 ) provided storage area ( 5 ) in the housing ( 3 ) a plastic layer ( 8th ) having. Ball joint according to one of the preceding claims, characterized in that the locking ring ( 4 ) in the area of the storage area ( 9 ) for the joint ball ( 2 ) a plastic layer ( 10 ) having. Ball joint according to claim 6 or 7, characterized in that the plastic layer ( 8th . 10 ) consists of PEEK. Ball joint according to one of claims 6 or 7, characterized in that the plastic layer ( 8th . 10 ) as a PTFE coating of the bearing surface ( 5 . 9 ) of the housing ( 3 ) and / or the locking ring ( 4 ) is executed. Ball joint according to one of the preceding claims, characterized in that the housing ( 3 ) at least on the pivot pin ( 1 ) opposite side lubrication grooves ( 11 ) for receiving lubricant. Ball joint according to one of the preceding claims, characterized in that the housing ( 3 ) for connection to other motor vehicle components at least one when casting with the housing ( 3 ) an integral unit connecting element ( 12 ) having. Method for producing a ball and socket joint according to one of Claims 1 to 11, characterized by the following method steps: - insertion of the pivot pin ( 1 ) into a mold tool mold ( 16 ), - filling a chamber cavity ( 18 ) with the liquid housing material, - cooling and curing of the housing ( 3 ), - removal of the prefabricated ball joint from the casting mold ( 16 ), - inserting the locking ring ( 4 ) in an existing receiving recess of the housing ( 3 ) and - forming a forming section ( 14 ) for fixing the ball joint components. Method for producing a ball and socket joint according to one of Claims 1 to 11, characterized by the following method steps: inserting a ball core having the geometry of the ball joint into a casting tool mold prepared therefor ( 16 ), - filling a chamber cavity ( 18 ) with the liquid housing material, - cooling and curing of the housing ( 3 ), - removal of the prefabricated ball joint from the casting mold ( 16 ), - removing the ball core and then inserting the ball joint ( 2 ) of the pivot pin ( 3 ) in the storage area ( 5 ) of the housing ( 3 ), - inserting the locking ring ( 4 ) in an existing receiving recess of the housing ( 3 ) and - forming a forming section ( 14 ) for fixing the ball joint components. Method according to one of the preceding claims 12 or 13, characterized in that prior to the casting of the housing material into the casting mold ( 16 ) in the shaft region of the housing to be cast ( 3 ) a connection element ( 12 ) is used. Method according to one of the preceding claims 12 to 14, characterized in that prior to assembly of the ball joint components, the bearing surface ( 5 ) of the housing ( 3 ) and / or the storage area ( 9 ) of the locking ring ( 4 ) with a plastic layer ( 8th . 10 ) is coated. A method according to claim 15, characterized ge indicates that the plastic layer is sprayed or vapor-deposited onto the surface to be coated. Method according to one of claims 12 to 16, characterized in that during assembly of the ball joint components, an increasing pressure force is exerted on the locking ring and with increasing pressure force for movement of the pivot pin ( 3 ) required torques are measured, wherein after reaching a predetermined torque of the forming section ( 14 ) of the housing ( 3 ) and thus the housing ( 3 ) is closed, so that the last determined torque is maintained.