Title of Invention

A JOINT CONNECTION

Abstract The invention relates to a method for producing a joint connection for the torque-transmitting connection of a component (1), which has a spur gearing (13), with a constant velocity joint (2), which is provided with a corresponding spur gearing (11). The spur gearings can be engaged with one another via means for applying an axial pretensioning, and have flanks, which are adjacent to one another while serving as functional surfaces. The invention also relates to a joint connection of the aforementioned type.
Full Text FORM 2
THE PATENT ACT 1970 (39 of 1970)
&
The Patents Rules, 2003 COMPLETE SPECIFICATION
(See Section 10, and rule 13)
1. TITLE OF INVENTION
METHOD FOR PRODUCING A JOINT CONNECTION AND JOINT CONNECTION

2. APPLICANT(S)
a) Name
b) Nationality
c) Address

SHAFT-FORM-ENGINEERING GMBH GERMAN Company DIESELSTRASSE 59,
63165 MUEHLHEIM,
GERMANY

3. PREAMBLE TO THE DESCRIPTION
The following specification particularly describes the invention and the manner in which it is to be performed : -

The invention relates to a method for producing a joint connection for the torque-transmitting connection of a component provided with spur gear teeth with a constant velocity joint provided with corresponding spur gear teeth, such that the spur gear teeth can be brought into interengagement by means for applying an axial bias and have flanks that contact each other as functional surfaces. The invention also relates to such a joint connection.
Flange connections for connecting a joint in a torque-transmitting and releasable manner to any other component, such as a shaft, are known in the art, but they require too much space for some applications.
Also known in the art is the insertion of a spline shaft into a correspondingly contoured bore of the joint to produce a torque transmitting connection. However, this connection requires a comparatively large axial assembly displacement path.
The German publications DE 36 36 243 C2, DE 43 10 007 CI and DE 43 10 008 C2 therefore propose joint connections where the outer hub of a joint is provided with spur gear teeth engageable for torque transmission with corresponding spur gear teeth on another component.
German publications DE 197 51 855 CI, DE 199 58 674 C2 and DE 101 27 458 C2 further describe a connection assembly where the outer hub of a joint can be coupled to a connecting element by spur gear teeth. These spur gear teeth may to a large extent be produced in a chipless forming process. The production of these spur gear teeth could be improved, however, with respect to both the manufacturing costs and the manufacturing accuracy of the spur gear teeth.
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It is therefore an object of the invention to provide a method of the above-described type and a corresponding joint connection that is distinguished by high manufacturing precision and at the same time by low manufacturing costs.
According to the invention, this object is essentially achieved by preforming the spur gear teeth in one or more process step(s) and then finishing only the functional surfaces to final dimensions. For example, the spur gear teeth are preformed by hot forming or warm forming and only the functional surfaces are subsequently finished to their final dimensions by coining.
It is preferred if at least in the last chipless process step only the functional surfaces are coined for displacement. Compared to chipless processing of the entire set of spur gear teeth where bearing pressure is created and high deformation forces are consequently necessary, the required deformation can be accomplished by displacement at comparatively low energy cost by processing only the functional surfaces. By coining the functional surfaces they can be finished to their final dimensions with very high, reproducible accuracy.
In a preferred embodiment of the method according to the invention, the functional surfaces increase to their final dimensions in the chipless finishing process. It may be advantageous in the preforming process to form the tooth shape of the spur gear teeth in such a way as to ensure, in the step of chipless finishing to the final dimensions, a free flow of material on the surfaces of the teeth that are adjacent the functional surfaces. This may be accomplished during preforming of the spur gear teeth particularly by forming a clearance, e.g., in the top and/or base region of each tooth to receive the material displaced during chipless finishing to the final dimensions. As a result, the amount of material that has to be displaced is minimized and, at the same time, bearing pressure occurs at the fewest possible points.
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If the spur gear teeth and possibly also components adjacent thereto are quenched and tempered or case hardened, the functional surfaces of the spur gear teeth can settle, e.g., when the axial bias is applied and/or a torque is transmitted. Because the spur gear teeth are statically overdetermined, a minimum degree of settling of the functional surfaces during assembly or during use of the joint connection is necessary and desirable. To this end it is advantageous if the core of the components is comparatively soft to facilitate settling whereas the outer layers are hard and durable.
The object underlying the invention is furthermore achieved by a joint connection that is preferably produced in accordance with the above-described method.
To center the component and the constant velocity joint in relation to each other, the spur gear teeth must have at least a small wedge angle. Preferably this wedge angle is located in proximity of the self-locking mechanism. However, to minimize the axial forces occurring during torque transmission in the joint connection according to the invention, the wedge angle of the spur gear teeth is preferably selected between approximately 1° and approximately 15°, particularly between approximately 1.5° and approximately 5°.
As an alternative or in addition, a preferred embodiment of the invention provides for engagement means on the component and on the (constant velocity) joint for connection with a union nut or a locknut, such that the locknut fixes the spur gear teeth intermeshingly under axial bias. To this end, the joint connection can have an inner hub, which is provided with the spur gear teeth at its one end. The outer hub of the constant velocity joint can be connected to a tubular shaft in a manner known per se.
If the inner hub has a cylindrical section whose one end is provided with the spur gear teeth, the outer surface of this cylindrical section can have means for fixing the locknut that is used to apply an axial bias. Similarly, the component being connected
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to the joint by means of the joint connection can also have a cylindrical-section whose one end is provided with the spur gear teeth and whose outer surface has means for fixing the locknut. The locknut can be held, for example, by means of a circlip, which engages in the groove of one of the two cylindrical sections and in a corresponding groove in the locknut, and can be screwed together with the other cylindrical section. This makes it possible to apply a defined axial bias to bring the two sets of spur gear teeth into engagement with each other.
According to yet another embodiment of the invention, the component and the inner hub of the constant velocity joint can each have a bore, at least one of which is provided with an internal thread, so that a defined axial bias can be applied by a threaded pin or a bolt that connects the component and the internal hub with each other. Particularly if the outer hub of the constant velocity joint is connected to a shaft it is preferred if the bolt is guided through a bore in the component and screwed into the inner hub.
The constant velocity joint is preferably an opposed path joint, particularly like the one disclosed in German publication DE 102 09 933 Al.
To enable the functional surfaces of the faces to settle, it is preferred if the inner hub of the constant velocity joint is case hardened. In contrast, the component being connected to the constant velocity joint, or at least the section provided with the spur gear teeth, can be quenched and tempered or also case hardened.
Further developments, advantages and potential applications of the invention also result from the following description of embodiments and from the drawings. All the described and/or illustrated features, either alone or in any combination, constitute the subject matter of the invention, regardless of how they are summarized in the claims or refer back to other claims.
The following show schematically:
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FIG 1: A sectional view of a joint connection according to a first embodiment of the invention,
FIG 2: A sectional view of a joint connection according to a second embodiment of the invention,
FIG 3: A sectional view of a joint connection according to a third embodiment of the invention, and
FIG 4: A tooth of a joint connection according to the invention in different manufacturing stages.
The joint connections depicted in FIG 1 to 3 each show in the upper half of the figure a constant velocity joint 2 that is coupled to a component 1, while in the lower half of the figure the component 1 is not yet coupled to the constant velocity joint 2. Like components in FIG 1 to 3 are identified by the same reference numerals.
The constant velocity joint 2 in the embodiments shown is an opposed path joint like the one disclosed in German publication 102 09 933 Al, for example.
The constant velocity joint 2 has an outer hub 3 with races 3a arranged on the inside of the outer hub 3, an inner hub 4 with inner races 4a arranged on the outside thereof, a cage 5 arranged between the inner hub 4 and the outer hub 3 and guided in the outer hub 3 as well as balls 6, which are guided in the races 3a and 4a. The outer hub 3 is enclosed by and non-rotatingly connected with sheet metal receiving means 7. The receiving means 7 is connected to a tubular shaft 9, e.g., by a weld joint 8.
The component 1 being connected to the constant velocity joint 2 can be any kind of component, e.g., a shaft, a wheel flange, another joint or the like. The inner hub 4 of the constant velocity joint 2 has a cylindrical section 10, which in the embodiment
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shown is a type of sleeve extending toward the component 1 and provided with spur gear teeth 11 at its end facing the component 1.
Similarly, the component 1 also has a cylindrical section 12 whose end facing the constant velocity joint 2 is provided with spur gear teeth 13. The spur gear teeth 11 and 13 are adapted to each other in such a way that they can intermesh to transmit a torque, as illustrated in the upper half of FIG 1 to 3.
The cylindrical section 12 of the component 1 can be integrally formed with the component 1, as shown in FIG 3. Alternatively, the cylindrical section 12 can also be a separate element that is non-rotatably connectable to the component 1, as shown in FIG 1 and 2. In the embodiments shown in FIG 1 and 2, the cylindrical section 12 is configured as a sleeve having a set of longitudinal teeth formed over at least a partial area of its inner surface, which is non-rotatably connectable to a corresponding set of longitudinal teeth 14 formed over a partial area on the outer surface of component 1.
The torque-transmitting connection between component 1 and the inner hub 4 of the constant velocity joint 2 is achieved by bringing the two sets of spur gear teeth 11 and 13 into engagement under an axial bias. To this end, in the embodiments shown in FIG 1 and 2, a locking nut 15 is provided, which has an internal thread that can be screwed onto an external thread 16 formed on the cylindrical section 12.
A groove formed in the cylindrical section 10 of the inner hub 4 holds a circlip 17, against which the locknut 15 rests with a projection 18 that faces the constant velocity joint 2. By a defined tightening of the locknut 15, the cylindrical section 12 of the component 1 can thus be pulled toward the cylindrical section 10 of the inner hub 4, such that the two sets of spur gear teeth 11 and 13 engage with each other.
In contrast, in the embodiment shown in FIG 3, the component 1 is provided with a bore 19. A threaded bore 20 is moreover formed in the inner hub 4 of the constant velocity joint 2. The component 1 and the inner hub 4 can therefore be screwed
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together by means of a threaded bolt 21 such that the gear teeth 11 and 13 engage with each other in a torque-transmitting manner.
The manufacture of the spur gear teeth 11 and 13 will now be explained in greater detail with reference to FIG 4. The spur gear teeth sets 11 and 13 each comprise a plurality of teeth. FIG 4 is a schematic illustration of tooth 22.
First, the teeth 22 of the spur gear teeth sets are preformed to give them for example the contour 23 indicated by a dashed line in FIG 4. Such preforming may be accomplished without chip removal, for example by hot forming. The teeth 22 are then chiplessly finished to their final dimensions so that they obtain the final contour
24 indicated by a solid line in FIG 4.
This chipless process step is preferably carried out in one or more coining processes in such a way that displacement pressure is applied only to the functional surfaces
25 of the tooth, i.e., the regions of the tooth flanks which in operation contact the
tooth flanks of the corresponding spur gear teeth. Because only the functional
surfaces 25 are subjected to the coining process, there is no bearing pressure in this
chipless process so that the functional surfaces 25 can be finished to their final
dimensions with low force but high precision.
The contour 23 of the preformed tooth is selected to ensure a free flow of material during the coining process along the surfaces adjoining the functional surfaces. To this end, e.g., a clearance 26 may be provided, into which the material displaced by deformation can flow. The clearance 26 shown in FIG 4 is indicated only by way of example. Depending on the final contour 24 of the teeth 22, different clearances and/or a clearance arranged at a different location may prove to be advantageous.
If the teeth 11 and 13 are quenched and tempered and/or case hardened, the functional surfaces 25 have the hardness required for torque transmission. The core of the teeth 22, however, is sufficiently soft so that the functional surfaces 25 can
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settle because of the axial bias applied by the locknut 15 or the threaded bolt 21 or because of the forces applied by torque transmission. Such settling is required in statically overdetermined gear teeth if all the teeth 22 are to transmit a torque as uniformly as possible.
9

WE CLAIM:
1. A method for producing a joint connection for the torque-transmitting connection of a component provided with spur gear teeth with a constant velocity joint provided with corresponding spur gear teeth, wherein said spur gear teeth can be brought into interengagement by means for applying an axial bias and have flanks contacting each other as functional surfaces, characterized in that the spur gear teeth are preformed in one or more process step(s) and are then finished to their final dimensions by chipless forming of only the functional surfaces.
2. A method as claimed in claim 1, characterized in that the spur gear teeth are preformed by hot or warm forming and only the functional surfaces are then finished to their final dimensions by coining.
3. A method as claimed in claim 2, characterized in that at least in the last chipless process step only the functional surfaces are coined for displacement.
4. A method as claimed in any one of claims 1 to 3, characterized in that the functional surfaces increase to their final dimensions as a result of the chipless finishing.
5. A method as claimed in any one of claims 1 to 4, characterized in that during preforming of the spur gear teeth, the tooth shape is formed in such a way as to ensure, during chipless finishing to the final dimensions, a free flow of material along the surfaces adjacent the functional surfaces of the teeth.
6. A method as claimed in claim 5, characterized in that during preforming of the spur gear teeth a clearance is formed in the top and/or base region of each tooth to receive the material displaced during chipless finishing to the final dimensions.
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7. A method as claimed in any one of claims 1 to 6, characterized in that at least the spur gear teeth are quenched and tempered and/or case hardened such that the functional surfaces of the spur gear teeth can settle when an axial bias is applied and/or a torque is transmitted.
8. A joint connection for the torque transmitting connection of a component provided with spur gear teeth with a joint provided with corresponding spur gear teeth, wherein said spur gear teeth can be brought into interengagement by means for applying an axial bias and have flanks that contact each other as functional surfaces, characterized in that engagement means are provided on the component and the joint for connection with a locknut such that the spur gear teeth can be intermeshingly fixed under an axial bias by the locknut.
9. A joint connection for the torque transmitting connection of a component provided with spur gear teeth with a joint provided with corresponding spur gear teeth, wherein said spur gear teeth can be brought into interengagement by means for applying an axial bias and have flanks that contact each other as functional surfaces, characterized in that the functional surfaces of the spur gear teeth have a wedge angle in proximity of the self-locking mechanism of between approximately 1° and approximately 15°, particularly between approximately 1.5° and approximately 5°.
10. A joint connection as claimed in claim 8 or 9 produced by a method as claimed in any one of the preceding claims.
11. A joint connection as claimed in claim 9, characterized in that the constant velocity joint has an inner hub whose one end is provided with the spur gear teeth.
12. A joint connection as claimed in 11, characterized in that the inner hub has a cylindrical section whose one end is provided with the spur gear teeth and
11

whose outer surface has means for fixing a locknut as the means for applying an axial bias.
13. A joint connection as claimed in any one of claims 8 to 12, characterized in that the component has a cylindrical section whose one end is provided with the spur gear teeth and whose outer surface has means for fixing a locknut as the means for applying an axial bias.
14. A joint connection as claimed in any one of claims 8 to 11, characterized in that the component and the inner hub of the constant velocity joint each have a bore, at least one of which is provided with an internal thread, through which a threaded bolt is screwed in to connect the component and the inner hub as the means for applying an axial bias.
15. A joint connection as claimed in any one of claims 8 to 14, characterized in that the constant velocity joint is an opposed path joint.
16. A joint connection as claimed in any one of claims 8 to 15, characterized in that the inner hub is case hardened and/or at least the section of the component that is provided with the spur gear teeth is quenched and tempered.
Dated this 30th day of August, 2007
















12


ABSTRACT
The invention relates to a method for producing a joint connection for the torque-transmitting connection of a component (1) provided with spur gear teeth (13) with a constant velocity joint (2) provided with corresponding spur gear teeth (11). The spur gear teeth can be brought into interengagement by means for applying an axial bias and have flanks that contact each other as functional surfaces. The invention also relates to a joint connection of the aforementioned type.
To,
The Controller of Patents,
The Patent Office,
13
Mumbai


Documents:

1323-MUMNP-2007-ABSTRACT(AMENDED)-(13-8-2011).pdf

1323-mumnp-2007-abstract.doc

1323-mumnp-2007-abstract.pdf

1323-MUMNP-2007-CANCELLED PAGES(25-1-2011).pdf

1323-MUMNP-2007-CLAIMS(AMENDED)-(13-4-2011).pdf

1323-MUMNP-2007-CLAIMS(AMENDED)-(25-1-2011).pdf

1323-MUMNP-2007-CLAIMS(GRANTED)-(29-4-2011).pdf

1323-MUMNP-2007-CLAIMS(MARKED COPY)-(13-4-2011).pdf

1323-MUMNP-2007-CLAIMS(MARKED COPY)-(25-1-2011).pdf

1323-mumnp-2007-claims.doc

1323-mumnp-2007-claims.pdf

1323-mumnp-2007-correspondence(15-11-2007).pdf

1323-MUMNP-2007-CORRESPONDENCE(25-1-2011).pdf

1323-MUMNP-2007-CORRESPONDENCE(30-3-2012).pdf

1323-MUMNP-2007-CORRESPONDENCE(7-4-2011).pdf

1323-MUMNP-2007-CORRESPONDENCE(IPO)-(2-5-2011).pdf

1323-mumnp-2007-correspondence-others.pdf

1323-mumnp-2007-correspondence-received.pdf

1323-mumnp-2007-description (complete).pdf

1323-MUMNP-2007-DESCRIPTION(GRANTED)-(29-4-2011).pdf

1323-MUMNP-2007-DRAWING(25-1-2011).pdf

1323-MUMNP-2007-DRAWING(31-8-2007).pdf

1323-MUMNP-2007-DRAWING(GRANTED)-(29-4-2011).pdf

1323-mumnp-2007-drawings.pdf

1323-MUMNP-2007-ENGLISH TRANSLATION(13-4-2011).pdf

1323-MUMNP-2007-FORM 1(13-11-2007).pdf

1323-MUMNP-2007-FORM 1(25-1-2011).pdf

1323-MUMNP-2007-FORM 1(31-8-2007).pdf

1323-MUMNP-2007-FORM 13(30-3-2012).pdf

1323-MUMNP-2007-FORM 2(GRANTED)-(29-4-2011).pdf

1323-MUMNP-2007-FORM 2(TITLE PAGE)-(25-1-2011).pdf

1323-MUMNP-2007-FORM 2(TITLE PAGE)-(31-8-2007).pdf

1323-MUMNP-2007-FORM 2(TITLE PAGE)-(GRANTED)-(29-4-2011).pdf

1323-MUMNP-2007-FORM 26(13-4-2011).pdf

1323-MUMNP-2007-FORM 26(25-1-2011).pdf

1323-MUMNP-2007-FORM 26(30-3-2012).pdf

1323-mumnp-2007-form 26(31-8-2007).pdf

1323-mumnp-2007-form 26(7-4-2011).pdf

1323-MUMNP-2007-FORM 3(25-1-2011).pdf

1323-MUMNP-2007-FORM PCT-IB-373(25-1-2011).pdf

1323-mumnp-2007-form pct-isa-210(22-10-2007).pdf

1323-MUMNP-2007-FORM PCT-ISA-237(25-1-2011).pdf

1323-mumnp-2007-form pct-ro-101(22-10-2007).pdf

1323-mumnp-2007-form-1.pdf

1323-mumnp-2007-form-18.pdf

1323-mumnp-2007-form-2.doc

1323-mumnp-2007-form-2.pdf

1323-mumnp-2007-form-3.pdf

1323-mumnp-2007-form-5.pdf

1323-mumnp-2007-pct-search report.pdf

1323-MUMNP-2007-PETITION UNDER RULE 137(25-1-2011).pdf

1323-MUMNP-2007-REPLY TO EXAMINATION REPORT(25-1-2011).pdf

1323-MUMNP-2007-REPLY TO HEARING(13-4-2011).pdf

1323-MUMNP-2007-SPECIFICATION(AMENDED)-(13-8-2011).pdf

1323-MUMNP-2007-WO INTERNATIONAL PUBLICATION REPORT(31-8-2007).pdf

abstract1.jpg


Patent Number 247652
Indian Patent Application Number 1323/MUMNP/2007
PG Journal Number 18/2011
Publication Date 06-May-2011
Grant Date 29-Apr-2011
Date of Filing 31-Aug-2007
Name of Patentee SHAFT-FORM-ENGINEERING GMBH
Applicant Address DIESELSTRASSE 59, 63165 MUEHLHEIM,
Inventors:
# Inventor's Name Inventor's Address
1 JACOB WERNER BRIANDRING 29, 60598 FRANKFURT AM MAIN
2 LUTZ MATHIAS BELTHLESTRASSE 41, 72020 TUEBINGEN
3 NIEDERHUEFNER MANFRED KREUZWEG 22, 65456 HANAU
PCT International Classification Number F16D1/076
PCT International Application Number PCT/EP2006/001846
PCT International Filing date 2006-02-28
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 102005012178.0 2005-03-15 Germany