Title of Invention	A SINTERED CLUTCH RING
Abstract	A sintered clutch ring (1) is described, comprising a rim of clutch teeth (2) which comprise wedge-like face surfaces (3, 4) intersecting in an axial plane and flanks (5) sloping downwardly under an angle of inclination from the tooth back (6) against the tooth root, with the flanks (5) being relieved starting from a reentrant, axially normal shoulder (7). In order to provide advantageous conditions for press forming the flank reliefs it is proposed that the planes of intersection between the wedge-like face surfaces (3, 4) extend outside of the center of the teeth and that the mutually axially offset shoulders (7) of the two flanks (5) of the clutch teeth (2) separate the relieved flanks (5) from a paraxial flank portion (8) which is substantially triangular and is adjacent to the face surfaces (3,4).

Title of Invention

A SINTERED CLUTCH RING

Abstract

A sintered clutch ring (1) is described, comprising a rim of clutch teeth (2) which comprise wedge-like face surfaces (3, 4) intersecting in an axial plane and flanks (5) sloping downwardly under an angle of inclination from the tooth back (6) against the tooth root, with the flanks (5) being relieved starting from a reentrant, axially normal shoulder (7). In order to provide advantageous conditions for press forming the flank reliefs it is proposed that the planes of intersection between the wedge-like face surfaces (3, 4) extend outside of the center of the teeth and that the mutually axially offset shoulders (7) of the two flanks (5) of the clutch teeth (2) separate the relieved flanks (5) from a paraxial flank portion (8) which is substantially triangular and is adjacent to the face surfaces (3,4).

Full Text	1. Field of the Invention The invention relates to a sintered clutch ring with a rim of clutch teeth which comprise wedge-like face surfaces intersecting in an axial plane and flanks sloping downwardly under an angle of inclination from the tooth back against the tooth root, with the flanks being relieved starting from a re-entrant, axially normal shoulder. 2. Description of the Prior Art Transmissions for motor vehicles comprise clutch rings which cooperate with a selector sleeve and whose clutch teeth form wedge-like face surfaces extend- ing in a roof-like manner on the side facing the selector sleeve, which face sur- faces facilitate the engagement of the claws of the selector sleeve in the gear rim of the clutch ring. By providing relief of the flanks of the clutch teeth, the engagement position of the claws of the selector shaft is secured in the axial di- rection. In order to produce the relief of the flanks, the clutch teeth are sub- jected in the case of a power-metallurgical production of the clutch rings to press forming between two molds of a form tool which are axially pressed against each other. In order to avoid the formation of fins in the region of the partition plane of the form tool and thus aftertreatment of the clutch ring, it has already been proposed (WO 01/08838 A1) that during form pressing of the re- lief of the flanks in the transitional region between the flanks and the wedge-like face surfaces a shoulder which re-enters on the flank side and is situated in the partition plane of the form tools is pressed into the flanks of the clutch teeth with a rounded transitional region to the wedge-like face surfaces. As a result of the re-entrant shoulder, it is not possible that a fin-like accumulation of material - 2 - occurs in the transitional region from the wedge-like face surfaces to the flanks, which accumulation would impair the engagement movement of the claws of the selector sleeve. The re-entrant shoulders have no influence on the en- gagement movement of the claws of the selector shaft into the rim of the clutch teeth. The precondition for such advantageous form pressing of the sintered clutch ring is a configuration of the clutch teeth which is symmetrical with re- spect to an axial plane. An asymmetrical arrangement of the wedge-like face surfaces of the clutch teeth offers advantages with respect to the switching process and the load on the wedge-like face surfaces under a predetermined direction of rotation, because the face surfaces which are relevant for the guid- ance of the claws of the selector sleeve form a respectively longer sliding sur- face. SUMMARY OF THE INVENTION The invention is thus based on the object or providing a clutch ring of the kind mentioned above in such a way that the reliefs of the flanks can be produced by form pressing of the sintered clutch ring despite an asymmetrical configura- tion of the wedge-like face surfaces. This object is achieved by the invention in such a way that the planes of inter- section between the wedge-like face surfaces extend outside of the center of the teeth and that the mutually axially offset shoulders of the two flanks of the clutch teeth separate the relieved flanks from a paraxial flank part which is sub- stantially triangular and is adjacent to the face surfaces. Since as a result of this measure the re-entrant shoulders do not extend along the inclined transitional region from the wedge-like face surfaces to the flanks, but instead along an axially normal plane, so that the shoulders separate the relieved flanks from a paraxial flank part which is substantially triangular and is adjacent to the face surfaces, advantageous preconditions for form pressing of the relieved flanks can be ensured despite the asymmetric arrangement of the _ 3 - wedge-like face surfaces, because the separating surface between the two molds of a form tool can be formed in the flank region by axially normal, parallel sections between which connecting surfaces must be provided which bridge the axial offset of the shoulders. The substantially triangular, paraxial flank parts adjacent to the wedge-like face surfaces neither obstruct the engagement of the claws of the selector sleeve, nor their axial securing by the relieved flanks of the teeth. Based on a sintered clutch ring with paraxial tooth flanks, the flank relief can be produced by means of the shoulders which are mutually axially offset and each extend along an axially normal plane with the help of a form tool made of two molds which can be pressed axially against each other, of which one forms the hollow mold for the clutch teeth in the region of the wedge-like face surfaces and the other the hollow mold for the clutch teeth in the region of the relieved flanks, with the partition surface between the two molds extending along the paraxial shoulders delimiting the relieved flanks. The relevant aspect is that the partition surface between the two molds is composed of plane sections which extend in the region of the flanks along the re-entrant shoulders in an axially normal manner and extend in the region of the tooth backs and tooth gaps in an inclined manner according to the axial direction between sections which are axially offset against each other between the same according to the axial offset. With such a partition surface it is not only possible to form the flank reliefs with the re-entrant shoulders in a subsequent manner, but otherwise required cen- tering measures for the molds of the form tool can be omitted, because an automatic mutual centering of the molds is given by the sections of the partition surface which extend in the region of the tooth backs and the tooth gaps in an inclined manner in the opposite direction, which has an advantageous effect on the production tolerances of the flank reliefs. BRIEF DESCRIPTION OF THE DRAWINGS - 4 - The subject matter of the invention is shown in the drawing by way of example, wherein: Fig. 1 shows a sintered clutch ring in accordance with the invention in a sec- tional developed top view of the gear rim of the clutch; Fig. 2 shows an illustration according to Fig. 1 of the sintered clutch ring be- tween the partly opened molds of the form tool; Fig. 3 shows a sectional view along line Ill-Ill of Fig. 2, and Fig 4 shows a sectional face view of the mold with the hollow mold for the clutch teeth in the region of the relieved flanks on a smaller scale. DESCRIPTION OF THE PREFERRED EMBODIMENTS As can be seen from Fig. 1, the sintered clutch ring 1 comprises a rim of clutch teeth 2 which form wedge-like face surfaces 3, 4 on a face side, which face sur- faces intersect in an axial plane extending outside of the center of the teeth, thus leading to an asymmetrical arrangement for the wedge-like face surfaces 3, 4. Said face surfaces 3, 4 converge into flanks 5 which slope downwardly from the tooth back 6 to the tooth root and which are relieved. The relieved flanks 5 are delimited by re-entrant shoulders 7 which each extend in an axially normal plane and separate the relieved flanks 5 from a paraxial flank portion 8 which is substantially triangular and is adjacent to the face surfaces 3, 4. The height of the shoulders 7 can be small and can be between 0.01 and 0.2 mm for example. For producing the flank reliefs delimited by the shoulders 7, a sintered clutch ring 1 is used in accordance with Fig. 2 whose clutch teeth 2 has paraxial flanks 5. For form pressing the relieved flanks 5 which are offset by the shoul- ders 7, a form tool 9 is used which consists of two molds 10 and 11, of which - 5 - mold 10 forms the hollow mold 12 for the clutch teeth 2 in the region of the wedge-like face surfaces 3, 4 and the other mold 11 forms the hollow mold 13 for the clutch teeth 2 in the region of the relieved flanks 5. The mold surfaces of the mold 10 corresponding to the wedge surfaces 3, 4 are designated with ref- erence numerals 3a and 4a, whereas the mold surfaces corresponding to the triangular flank parts 8 are designated with reference numeral 8a. The mold surfaces of mold 11 belonging to the relieved flanks 5 have the reference nu- meral 5a. As a result of the axially normal extension of the shoulders 7 of flanks 5, a pro- gress 14 is obtained for the partition surfaces between the two molds, as is shown in Fig. 1 with the dot-dash line. Said progress 14 shows that the partition surfaces in the region of the shoulders 7 comprise axially normal, plane sec- tions 15 which are joined by sections 16 an 17 which are inclined in opposite di- rections in the region of the tooth backs 6 and the tooth gaps, as is shown es- pecially in Figs. 2 and 4. As a result of this partition surface of molds 10 and 11 as is composed of the plane sections 15, 16 and 17, the flank reliefs starting out from the re-entrant shoulders can be produced in an advantageous manner by press forming. The sections 16 and 17 which are inclined in opposite directions cause a mutual self-centering of the molds 10 and 11, thus leading to overall simple production conditions by securing high production precision. - 6 - We claim :- 1. A sintered clutch ring (1) with a rim of clutch teeth (2) which comprise wedge-like face surfaces (3, 4) intersecting in an axial plane and flanks (5) sloping downwardly under an angle of inclination from the tooth back (6) against the tooth root, with the flanks (5) being relieved starting from a re- entrant, axially normal shoulder (7), characterized in that the planes of intersec- tion between the wedge-like face surfaces (3, 4) extend outside of the center of the teeth and that the mutually axially offset shoulders (7) of the two flanks (5) of the clutch teeth (2) separate the relieved flanks (5) from a paraxial flank por- tion (8) which is substantially triangular and is adjacent to the face surfaces (3, 4). 2. A form tool (9) for producing a clutch ring (1) according to claim 1, com- prising two molds (10, 11) which can be pressed axially against each other and of which one forms the hollow mold (12) for the clutch teeth (2) in the region of the wedge-like face surfaces (3, 4) and the other the hollow mold (13) for the clutch teeth (2) in the region of the relieved flanks (5), with the partition surface between the two molds (10,11) extending along the paraxial shoulders (7) de- limiting the relieved flanks (5), characterized in that the partition surface be- tween the two molds (10, 11) is composed of plane sections (15, 16, 17) which extend in the region of the flanks along the re-entrant shoulders (7) in an axially normal manner and extend in the region of the tooth backs (6) and tooth gaps between the same in an inclined manner according to the axial direction be- tween the sections (15) which are axially offset against each other according to the axial offset. A sintered clutch ring (1) is described, comprising a rim of clutch teeth (2) which comprise wedge-like face surfaces (3, 4) intersecting in an axial plane and flanks (5) sloping downwardly under an angle of inclination from the tooth back (6) against the tooth root, with the flanks (5) being relieved starting from a reentrant, axially normal shoulder (7). In order to provide advantageous conditions for press forming the flank reliefs it is proposed that the planes of intersection between the wedge-like face surfaces (3, 4) extend outside of the center of the teeth and that the mutually axially offset shoulders (7) of the two flanks (5) of the clutch teeth (2) separate the relieved flanks (5) from a paraxial flank portion (8) which is substantially triangular and is adjacent to the face surfaces (3,4).

Full Text

1. Field of the Invention
The invention relates to a sintered clutch ring with a rim of clutch teeth which
comprise wedge-like face surfaces intersecting in an axial plane and flanks
sloping downwardly under an angle of inclination from the tooth back against
the tooth root, with the flanks being relieved starting from a re-entrant, axially
normal shoulder.
2. Description of the Prior Art
Transmissions for motor vehicles comprise clutch rings which cooperate with a
selector sleeve and whose clutch teeth form wedge-like face surfaces extend-
ing in a roof-like manner on the side facing the selector sleeve, which face sur-
faces facilitate the engagement of the claws of the selector sleeve in the gear
rim of the clutch ring. By providing relief of the flanks of the clutch teeth, the
engagement position of the claws of the selector shaft is secured in the axial di-
rection. In order to produce the relief of the flanks, the clutch teeth are sub-
jected in the case of a power-metallurgical production of the clutch rings to
press forming between two molds of a form tool which are axially pressed
against each other. In order to avoid the formation of fins in the region of the
partition plane of the form tool and thus aftertreatment of the clutch ring, it has
already been proposed (WO 01/08838 A1) that during form pressing of the re-
lief of the flanks in the transitional region between the flanks and the wedge-like
face surfaces a shoulder which re-enters on the flank side and is situated in the
partition plane of the form tools is pressed into the flanks of the clutch teeth
with a rounded transitional region to the wedge-like face surfaces. As a result of
the re-entrant shoulder, it is not possible that a fin-like accumulation of material
- 2 -

occurs in the transitional region from the wedge-like face surfaces to the flanks,
which accumulation would impair the engagement movement of the claws of
the selector sleeve. The re-entrant shoulders have no influence on the en-
gagement movement of the claws of the selector shaft into the rim of the clutch
teeth. The precondition for such advantageous form pressing of the sintered
clutch ring is a configuration of the clutch teeth which is symmetrical with re-
spect to an axial plane. An asymmetrical arrangement of the wedge-like face
surfaces of the clutch teeth offers advantages with respect to the switching
process and the load on the wedge-like face surfaces under a predetermined
direction of rotation, because the face surfaces which are relevant for the guid-
ance of the claws of the selector sleeve form a respectively longer sliding sur-
face.
SUMMARY OF THE INVENTION
The invention is thus based on the object or providing a clutch ring of the kind
mentioned above in such a way that the reliefs of the flanks can be produced
by form pressing of the sintered clutch ring despite an asymmetrical configura-
tion of the wedge-like face surfaces.
This object is achieved by the invention in such a way that the planes of inter-
section between the wedge-like face surfaces extend outside of the center of
the teeth and that the mutually axially offset shoulders of the two flanks of the
clutch teeth separate the relieved flanks from a paraxial flank part which is sub-
stantially triangular and is adjacent to the face surfaces.
Since as a result of this measure the re-entrant shoulders do not extend along
the inclined transitional region from the wedge-like face surfaces to the flanks,
but instead along an axially normal plane, so that the shoulders separate the
relieved flanks from a paraxial flank part which is substantially triangular and is
adjacent to the face surfaces, advantageous preconditions for form pressing of
the relieved flanks can be ensured despite the asymmetric arrangement of the
_ 3 -

wedge-like face surfaces, because the separating surface between the two
molds of a form tool can be formed in the flank region by axially normal, parallel
sections between which connecting surfaces must be provided which bridge
the axial offset of the shoulders. The substantially triangular, paraxial flank
parts adjacent to the wedge-like face surfaces neither obstruct the engagement
of the claws of the selector sleeve, nor their axial securing by the relieved
flanks of the teeth.
Based on a sintered clutch ring with paraxial tooth flanks, the flank relief can be
produced by means of the shoulders which are mutually axially offset and each
extend along an axially normal plane with the help of a form tool made of two
molds which can be pressed axially against each other, of which one forms the
hollow mold for the clutch teeth in the region of the wedge-like face surfaces
and the other the hollow mold for the clutch teeth in the region of the relieved
flanks, with the partition surface between the two molds extending along the
paraxial shoulders delimiting the relieved flanks. The relevant aspect is that the
partition surface between the two molds is composed of plane sections which
extend in the region of the flanks along the re-entrant shoulders in an axially
normal manner and extend in the region of the tooth backs and tooth gaps in
an inclined manner according to the axial direction between sections which are
axially offset against each other between the same according to the axial offset.
With such a partition surface it is not only possible to form the flank reliefs with
the re-entrant shoulders in a subsequent manner, but otherwise required cen-
tering measures for the molds of the form tool can be omitted, because an
automatic mutual centering of the molds is given by the sections of the partition
surface which extend in the region of the tooth backs and the tooth gaps in an
inclined manner in the opposite direction, which has an advantageous effect on
the production tolerances of the flank reliefs.
BRIEF DESCRIPTION OF THE DRAWINGS
- 4 -

The subject matter of the invention is shown in the drawing by way of example,
wherein:
Fig. 1 shows a sintered clutch ring in accordance with the invention in a sec-
tional developed top view of the gear rim of the clutch;
Fig. 2 shows an illustration according to Fig. 1 of the sintered clutch ring be-
tween the partly opened molds of the form tool;
Fig. 3 shows a sectional view along line Ill-Ill of Fig. 2, and
Fig 4 shows a sectional face view of the mold with the hollow mold for the
clutch teeth in the region of the relieved flanks on a smaller scale.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
As can be seen from Fig. 1, the sintered clutch ring 1 comprises a rim of clutch
teeth 2 which form wedge-like face surfaces 3, 4 on a face side, which face sur-
faces intersect in an axial plane extending outside of the center of the teeth,
thus leading to an asymmetrical arrangement for the wedge-like face surfaces
3, 4. Said face surfaces 3, 4 converge into flanks 5 which slope downwardly
from the tooth back 6 to the tooth root and which are relieved. The relieved
flanks 5 are delimited by re-entrant shoulders 7 which each extend in an axially
normal plane and separate the relieved flanks 5 from a paraxial flank portion 8
which is substantially triangular and is adjacent to the face surfaces 3, 4. The
height of the shoulders 7 can be small and can be between 0.01 and 0.2 mm
for example.
For producing the flank reliefs delimited by the shoulders 7, a sintered clutch
ring 1 is used in accordance with Fig. 2 whose clutch teeth 2 has paraxial
flanks 5. For form pressing the relieved flanks 5 which are offset by the shoul-
ders 7, a form tool 9 is used which consists of two molds 10 and 11, of which
- 5 -

mold 10 forms the hollow mold 12 for the clutch teeth 2 in the region of the
wedge-like face surfaces 3, 4 and the other mold 11 forms the hollow mold 13
for the clutch teeth 2 in the region of the relieved flanks 5. The mold surfaces of
the mold 10 corresponding to the wedge surfaces 3, 4 are designated with ref-
erence numerals 3a and 4a, whereas the mold surfaces corresponding to the
triangular flank parts 8 are designated with reference numeral 8a. The mold
surfaces of mold 11 belonging to the relieved flanks 5 have the reference nu-
meral 5a.
As a result of the axially normal extension of the shoulders 7 of flanks 5, a pro-
gress 14 is obtained for the partition surfaces between the two molds, as is
shown in Fig. 1 with the dot-dash line. Said progress 14 shows that the partition
surfaces in the region of the shoulders 7 comprise axially normal, plane sec-
tions 15 which are joined by sections 16 an 17 which are inclined in opposite di-
rections in the region of the tooth backs 6 and the tooth gaps, as is shown es-
pecially in Figs. 2 and 4.
As a result of this partition surface of molds 10 and 11 as is composed of the
plane sections 15, 16 and 17, the flank reliefs starting out from the re-entrant
shoulders can be produced in an advantageous manner by press forming. The
sections 16 and 17 which are inclined in opposite directions cause a mutual
self-centering of the molds 10 and 11, thus leading to overall simple production
conditions by securing high production precision.
- 6 -

We claim :-
1. A sintered clutch ring (1) with a rim of clutch teeth (2) which comprise
wedge-like face surfaces (3, 4) intersecting in an axial plane and flanks (5)
sloping downwardly under an angle of inclination from the tooth back (6)
against the tooth root, with the flanks (5) being relieved starting from a re-
entrant, axially normal shoulder (7), characterized in that the planes of intersec-
tion between the wedge-like face surfaces (3, 4) extend outside of the center of
the teeth and that the mutually axially offset shoulders (7) of the two flanks (5)
of the clutch teeth (2) separate the relieved flanks (5) from a paraxial flank por-
tion (8) which is substantially triangular and is adjacent to the face surfaces (3,
4).
2. A form tool (9) for producing a clutch ring (1) according to claim 1, com-
prising two molds (10, 11) which can be pressed axially against each other and
of which one forms the hollow mold (12) for the clutch teeth (2) in the region of
the wedge-like face surfaces (3, 4) and the other the hollow mold (13) for the
clutch teeth (2) in the region of the relieved flanks (5), with the partition surface
between the two molds (10,11) extending along the paraxial shoulders (7) de-
limiting the relieved flanks (5), characterized in that the partition surface be-
tween the two molds (10, 11) is composed of plane sections (15, 16, 17) which
extend in the region of the flanks along the re-entrant shoulders (7) in an axially
normal manner and extend in the region of the tooth backs (6) and tooth gaps
between the same in an inclined manner according to the axial direction be-
tween the sections (15) which are axially offset against each other according to
the axial offset.

A sintered clutch ring (1) is described, comprising a rim of clutch teeth (2) which
comprise wedge-like face surfaces (3, 4) intersecting in an axial plane and
flanks (5) sloping downwardly under an angle of inclination from the tooth back
(6) against the tooth root, with the flanks (5) being relieved starting from a
reentrant, axially normal shoulder (7). In order to provide advantageous
conditions for press forming the flank reliefs it is proposed that the planes of
intersection between the wedge-like face surfaces (3, 4) extend outside of the center of
the teeth and that the mutually axially offset shoulders (7) of the two flanks (5)
of the clutch teeth (2) separate the relieved flanks (5) from a paraxial flank portion (8) which is substantially triangular and is adjacent to the face surfaces (3,4).

Documents:

02133-kolnp-2007-abstract.pdf

02133-kolnp-2007-claims.pdf

02133-kolnp-2007-correspondence others 1.1.pdf

02133-kolnp-2007-correspondence others 1.2.pdf

02133-kolnp-2007-correspondence others.pdf

02133-kolnp-2007-description complete.pdf

02133-kolnp-2007-drawings 1.1.pdf

02133-kolnp-2007-drawings.pdf

02133-kolnp-2007-form 1 1.1.pdf

02133-kolnp-2007-form 1.pdf

02133-kolnp-2007-form 2.pdf

02133-kolnp-2007-form 3.pdf

02133-kolnp-2007-form 5 1.1.pdf

02133-kolnp-2007-form 5.pdf

02133-kolnp-2007-international publication.pdf

02133-kolnp-2007-international search report.pdf

02133-kolnp-2007-others.pdf

2133-KOLNP-2007-(04-10-2012)-ABSTRACT.pdf

2133-KOLNP-2007-(04-10-2012)-ANNEXURE TO FORM 3.pdf

2133-KOLNP-2007-(04-10-2012)-CLAIMS.pdf

2133-KOLNP-2007-(04-10-2012)-CORRESPONDENCE.pdf

2133-KOLNP-2007-(04-10-2012)-DESCRIPTION (COMPLETE).pdf

2133-KOLNP-2007-(04-10-2012)-DRAWINGS.pdf

2133-KOLNP-2007-(04-10-2012)-ENGLISH TRANSLATION OF PRIORITY DOCUMENT.pdf

2133-KOLNP-2007-(04-10-2012)-FORM-1.pdf

2133-KOLNP-2007-(04-10-2012)-FORM-2.pdf

2133-KOLNP-2007-(04-10-2012)-OTHERS.pdf

2133-KOLNP-2007-(04-10-2012)-PETITION UNDER RULE 137.pdf

2133-kolnp-2007-form 18.pdf

2133-KOLNP-2007-PA.pdf

abstract-02133-kolnp-2007.jpg

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Patent Number

255871

Indian Patent Application Number

2133/KOLNP/2007

PG Journal Number

13/2013

Publication Date

29-Mar-2013

Grant Date

26-Mar-2013

Date of Filing

12-Jun-2007

Name of Patentee

MIBA SINTER AUSTRIA GMBH

Applicant Address

DR. MITTERBAUER STRASSE 3, A 4663 LAAKIRCHEN

Inventors:

#	Inventor's Name	Inventor's Address
1	HEITZINGER, FRANZ	HAIDERMOOS 18, A 4654 BAD WIMSBACH/ NEYDHARTING
2	NELBOCK, GUNTER	DR.-FRITZ-SEIFERT-STRASSE 13 A 4863 SEEWALCHEN
3	WEIERMAIR, ALEXANDER	KAPELLENWEG 18, A 4653 EBERSTALZELL

PCT International Classification Number

B21K 1/30, B22F 5/08

PCT International Application Number

PCT/AT2005/000451

PCT International Filing date

2005-11-14

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1	A 2153/2004	2004-12-23	Austria