Title of Invention

SEALING BELLOWS WITH LUBRICANT RESERVOIR AT AXIAL END AND ASSEMBLY / INSTALLATION METHOD

Abstract A process for forming the ball and socket joint with bellows seal (10), a bellows seal (10) and a ball and socket joint with bellows seal (10) is provided including a ball pivot pin (36, 38) with a connection piece (40). The sealing bellows is provided with an annular engagement surface (16) with a cavity (20). The connection piece with a sealing face is connected to the ball pivot pin. Lubricant (22) is disposed in the cavity prior to assembly of the ball and socket joint. The annular engagement surface (16) is provided in contact with the sealing face upon assembly to cause an amount of lubricant (22) to be squeezed out of the cavity (20).
Full Text FORM 2
THE PATENT ACT 197 0 (39 of 1970)
The Patents Rules, 2003 COMPLETE SPECIFICATION (See Section 10, and rule 13!
TITLE OF INVENTION
SEALING BELLOWS WITH LUBRICANT RESERVOIR AT AXIAL END AND
ASSEMBLY/INSTALLATION METHOD

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

ZF FRIEDRICHSHAFEN AG
GERMAN Company
GEWERBLICHE SCHUTZRECHTE,
TORALF HUTTNER, GRAF-VON-SODEN PLATZ 1,
88046 FRIEDRICHSHAFEN,
GERMANY

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

FIELD OF THE INVENTION
The present invention relates generally to joints and more particularly to a ball and
socket joint assembly with a bellows or sealing boot and to the sealing boot.
BACKGROUND OF THE INVENTION
Ball and socket joins are known that have a sealing boot connected at one end to a housing of the ball joint and connected at another end to a knuckle (the connected piece or mating part - connected to the ball pin) and/or to the ball stud (ball pin). The end of the sealing boot is either directly applied to the ball stud or knuckle or is applied by the use of a sealing ring.
Sealing boots that are lubricated on the axial side to improve sliding behavior are known.
SUMMARY OF THE INVENTION
It is an object of the invention to provide a sealing bellows (sealing boot) for a joint that has an axial end (facing the knuckle) that is lubricated at the knuckle contact surface without getting on other joint parts (such as the ball stud).
It is an object of the invention to provide a sealing boot (bellows seal) to ball and socket joint part assembly and method of assembling that presents a good seal, particularly in an axial direction of the sealing boot and knuckle and in which the lubricant is protected in position on the sealing boot during shipment and is released in a simple manner on filial assembly.
According to the invention, a ball and socket joint with bellows seal is provided including a ball pivot pin with a connection piece. A sealing bellows is provided with an annular engagement surface with a cavity. A connection piece with a sealing face is connected to the ball pivot pin. Lubricant is disposed in the cavity prior to assembly of the ball and socket joint. The annular engagement surface is provided in
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contact with the sealing face upon assembly to cause an amount of lubricant to be squeezed out of the cavity.
The cavity may be a groove with an annular opening with a flap portion at each side of said opening to restrict movement of the lubricant from the cavity until assembly. The cavity may also be a groove with an annular opening to the cavity in the form of a narrowed entrance gap with the annular engagement surface at each side of the narrowed entrance gap, the narrowed entrance gap restricting movement of the lubricant from the cavity until assembly.
The cavity may have an annular engagement surface side closed by one of a material of the sealing bellows and a membrane applied to the sealing bellows. The annular engagement surface side opening may allow a release of lubricant upon assembly.
The sealing bellows at the cavity may have a lubricant retaining portion defined by one of a narrowed gap and a material barrier at an entrance of the cavity. The lubricant retaining portion acts to retain at least a portion of the lubricant in the groove in a pre-assembly state prior to the annular engagement surface contacting the sealing face.
The bellows seal element may also have a pivot pin sealing surface engaged with the pivot pin. A clamping ring may be applied acting on an outside of the bellows to apply force to the bellows such that the pivot pin sealing surface statically engages with the pivot pin.
According to a further aspect of the invention, a process is provided for forming a ball and socket joint. The process includes providing a ball pivot pin seated in a ball joint housing via a bearing insert and providing a connection part with a radically extending surface having an opening for receiving the ball pivot pin as well as a bellows with a first connection end with an annular housing connection surface and
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another end with an annular engagement surface having a cavity at least partially filled with a lubricant. The bellows is connected to the housing. The ball pivot pin is moved into the opening of the connection part with the bellows contacting the annular engagement surface to the radially extending surface of the connection part to release lubricant from the cavity to a location between the annular engagement surface and the radically extending surface of the connection part.
According to a further aspect of the invention, a sealing boot is provided comprising a bellow element with an end having annular engagement surface and a cavity formed in the bellows element and opening to the annular engagement surface. A lubricant is disposed in the cavity.
The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference is made to the accompanying drawings and descriptive matter in which preferred embodiments of the invention are illustrated.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 is a sectional cutaway view showing an axial end of the boot seal with lubricant groove, pocket or pore according to the invention;
Figure 2 is a sectional cutaway view showing an axial end of the boot seal that is pressed so lubricant in the lubricant groove, pocket or pore is released;
Figure 3 A is a sectional view of a knuckle facing side (axial end) of the sealing boot with lubricant groove, pocket or pore covered at least partially by a film or membrane (with or without perforation) or material flaps;
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Figure 3B is a sectional view of an alternative embodiment of the sealing boot at a knuckle facing side (axial end) of the sealing boot with lubricant groove, pocket or pore having a restricted dimension opening;
Figure 4 is a partial sectional view of a ball joint ball and pin seated in a housing connected to a bellows (sealing boot) according to the invention;
Figure 5 is a sectional view showing a connected piece (knuckle) with a bellows contact surface (upper surface);
Figure 6A is a sectional view showing a state of assembly with the sealing boot contacting the knuckle contact surface;
Figure 6B is a sectional view showing another state of assembly as the ball pin advances with respect to the connected piece;
Figure 6C is a sectional view showing the assembled state;
Figure 7 A is an enlarged sectional view showing the sealing boot in a pre- assembly state, relatively positioned for engagement; and
Figure 7B is an enlarged sectional view showing the sealing boot and knuckle;
DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawings in particular, the invention comprises a sealing bellows or sealing boot generally designated 10. The sealing boot 10 has a housing end 15 (see Figure 4) and a connection piece end 18. The connection piece end 18 has an annular surface 16 with an a cavity 20 in the form of an annular lubricant groove or pocket. The cavity is filled at least partially with a lubricant 22. The cavity 20 is closed on one side by material forming flaps 30.
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Figure 2 shows the sealing boot 10 with the end 18 pressed at an inside 14 relative to an outside 12. The pressing at side 14 results in pressure on the lubricant 22, such that the flaps 30 are urged outwardly and lubricant 22 can flow through a gap between flaps 30.
The pore, pocket or groove 20 provided with a lubricant 22 is shown in Figure 3 A. This lubricant 22 may be supplied in a reassembled state with the lubricant 22 already in position within the cavity 20. According to the embodiment of Figs. 1, 2 and 3 A, flaps 30 or a film or membrane thickness of material 70 is integrally formed with the sealing boot 10. The material 70 may extend uninterrupted across the lubricant cavity 20 or have a gap as shown in Fig. 3 A. If no gap is provided, the lubricant 22 is injected through the membrane or material 70. The cavity 20 as shown ill Fig. 3A is covered with flaps 30 extending from each sidewall at the surface 16. Prior to forming an assembly with the sealing boot 10, the lubricant 22 is fed into the groove 20, passing through the gap in the flaps 30. The flaps 30 effectively retain the lubricant 22 within the groove 20 until the surface 16 is positioned in an assembly position, in which case the lubricant is pressed out of the groove 20, as discussed further below.
Figure 3B shows an alternative embodiment of the cavity 20. The cavity or groove 20 cooperates with the surface 16 to define a gap 24. The gap 24 may have an advantageous ratio of the width d of the gap 24 to the width D of the cavity or groove 20. With a sufficiently small dimension d, the lubricant may be substantially retained in the space 22, even during shipping and handling. Further, a film may be applied over the gap 24 during shipping and handling. The lubricant may also be retained with a membrane formed integrally with sealing boot 18 wherein the lubricant is injected through the membrane. The membrane may then be broken to release the lubricant or preferably the lubricant is pressed out of the groove 20 during the assembly steps in which the membrane is broken or ruptured by the
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pressing (and from the internal pressure of the lubricant 22). The membrane may be perforated to define a weak area to rupture for lubricant 22 to be squeezed out of the cavity 20. The material 70 may have such a perforation or be precut to form the flaps 30 or such that flaps 30 form as the lubricant flows out of cavity 20 and the barrier 70 is ruptured.
Although the examples show the cavity 20 as a groove or continuous annular pocket 20, the cavity 20 may also be provided as one of several discrete pockets or pores that each have lubricant and retain the lubricant in any manner as described above. The material 70 may either be molded with the material of sealing boot 10 or the material to restrict passage of the lubricant may be applied to the already molded sealing boot 10.
Tire sealing boot 10 is advantageously used with a ball and socket joint including a ball 36 with a pin 38 as shown in Figure 4. The ball 36 is seated in a housing 44 via an intermediate bearing insert 45. The pin 38 is connected to a connecting piece or knuckle 40. The sealing boot 10 is connected at end 15 to the housing 44 via a clamping ring 46. The end 18 of sealing boot 10 is connected to the pin 38 by a clamping ring 48.
Figure 5 shows the knuckle 40 with a sealing boot facing surface 42. Tire surface 42 cooperates with the sealing boot surface 16 to form a seal between the sealing boot 10 and knuckle 40.
Figure 6 A - 6C show the assembly process in which a tapered surface of the pin 38 is seated in contact with the tapered surface of the knuckle 40. In figure 7A the surface 16 is positioned over the surface 42 (see also Figure 7A). With the movement of the stud 38 into a seated position in the opening of the knuckle 40 the sealing boot 10 applies force toward the knuckle 40. Some amount of lubricant 22 may exit the space 22 for reducing friction for relative slip between sealing boot 10 and slipping ring 14
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and for improving sealing characteristics. As shown in Figure 7B, a good seal is provided based on the water ingress path 55 passing through to lubricant 22.
While specific embodiments of the invention have been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles.
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APPENDIX
LIST OF REFERENCE NUMBERS
sealing bellows or sealing boot 10
an outside 12
an inside 14
housing end 15
annular surface 16
connection piece end 18
cavity, pore, pocket or groove 20
lubricant 22
gap 24
material forming flaps 30
ball 36
pin 38
connecting piece or knuckle 40
sealing boot facing surface 42
housing 44
intermediate bearing insert 45
clamping ring 46
clamping ring 48
water ingress path 55
a film or membrane thickness of material 70
width D
dimension d
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WE CLAIM:
1. A ball and socket joint with bellows seal, the ball and socket joint comprising:
a ball pivot pin with a connection piece;
a sealing bellows with an annular engagement surface with a cavity;
a connection piece with a sealing face;
lubricant disposed in said cavity prior to assembly of the ball and socket joint,
the annular engagement surface contacting said sealing face upon assembly to
cause an amount of lubricant to be squeezed out of said cavity.
2. A bellows seal according to claim 1, wherein said cavity is a groove with an annular opening with a flap portion at each side of said opening to restrict movement of the lubricant from said cavity until assembly.
3. A bellows seal according to claim 1, wherein said cavity is a groove with an annular opening to said cavity in the form of a narrowed entrance gap with said annular engagement surface at each side of said narrowed entrance gap, said narrowed entrance gap restricting movement of the lubricant from said cavity until assembly.
4. A bellows seal according to claim 1, wherein said cavity has an annular engagement surface side closed by one of a material of said sealing bellows and membrane applied to said sealing bellows, said annular engagement surface side opening to allow a release of lubricant upon assembly.
5. A bellows seal according to claim 1, wherein said sealing bellows at said cavity has a lubricant retaining portion defined by one of a narrowed gap and a material barrier at an entrance of said cavity, said lubricant retaining portion acting to retain at least a portion of said lubricant in said cavity in a pre-
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assembly state prior to said annular engagement surface contacting said sealing face.
6. A bellows seal according to claim 1, wherein said bellows seal element has a pivot pin sealing surface engaged with said pivot pin.
7. A bellows seal according to claim 6, further comprising a clamping ring acting on an outside of the bellows to apply force to the bellows such that the pivot pin sealing surface statically engages with said pivot pin.
8. A process for forming a ball and socket joint the process comprising: providing a ball pivot pin seated in a ball joint housing via a bearing insert; providing a connection part with a radically extending surface having an opening for receiving the ball pivot pin;
providing a bellows with a first connection end with an annular housing connection surface and another end with an annular engagement surface having a cavity at least partially filled with a lubricant; connecting the bellows to the housing;
moving said ball pivot pin into the opening of the connection part and contacting said annular engagement surface of said bellows to said radically extending surface of said connection part to release lubricant from said cavity to a location between said annular engagement surface and said radically extending surface of said connection part.
9. A process according to claim 8, wherein said cavity is a groove with an annular opening with a flap portion at each side of said opening to restrict movement of the lubricant from said cavity until assembly.
10. A process according to claim 8, wherein said cavity is a groove with an annular opening to said cavity in the form of a narrowed entrance gap with
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said annular engagement surface at each side of said narrowed entrance gap, said narrowed entrance gap restricting movement of the lubricant from said cavity until assembly.
11. A process according to claim 8, wherein said cavity has an annular engagement surface side closed by one of a material of said sealing bellows and membrane applied to said sealing bellows, said annular engagement surface side opening to allow a release of lubricant upon assembly.
12. A process according to claim 8, wherein said sealing bellows at said cavity has a lubricant retaining portion defined by one of a narrowed gap and a material barrier at an entrance of said cavity, said lubricant retaining portion acting to retain at least a portion of said lubricant in said sliding ring groove in a pre-assembly state prior to said annular engagement surface contacting said sealing face.
13. A sealing boot, comprising:
a bellow element with an end having annular engagement surface;
a cavity formed in said bellows element and opening to said annular
engagement surface;
lubricant disposed in said cavity.
14. A sealing boot according to claim 13, further comprising a lubricant retaining means for substantially retaining said lubricant in said cavity prior to said sealing boot beinA employed in a ball and socket joint assembly and allowing a release of an amount of lubricant upon the sealing boot being employed in a ball and socket joint assembly.
15. A sealing boot according to claim 14, wherein said lubricant retaining means is defined by one of a narrowed gap at an entrance to said cavity, a material
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barrier at an entrance of said cavity and a portion of said bellows element at least partially covering said cavity, said lubricant retaining portion acting to retain at least a portion of said lubricant in said cavity in a pre-assembly state and releasing.
16. A sealing boot according to claim 14, wherein said end of said bellows element has a pivot pin sealing surface engaged with said pivot pin, said pivot sealing surface being adjacent to said annular engagement surface.
17. A sealing boot according to claim 16, further comprising a clamping ring receiving surface to receive a clamping ring on an outside of said bellows element to apply force to the bellows element such that the pivot pin sealing surface statically engages with said pivot pin.
Dated this 15th day of January, 2007
HIRAL CHANDRCANT JOSHI AGENT TOR
ZF FRIEDRICHSHAFEN AG
13

ABSTRACT
A process for forming the ball and socket joint with bellows seal (10), a bellows seal (10) and a ball and socket joint with bellows seal (10) is provided including a ball pivot pin (36, 38) with a connection piece (40). The sealing bellows is provided with an annular engagement surface (16) with a cavity (20). The connection piece with a sealing face is connected to the ball pivot pin. Lubricant (22) is disposed in the cavity prior to assembly of the ball and socket joint. The annular engagement surface (16) is provided in contact with the sealing face upon assembly to cause an amount of lubricant (22) to be squeezed out of the cavity (20).
To,
The Controller of Patents,
The Patent Office,
Mumbai
14

Documents:

75-MUMNP-2007-ABSTRACT(23-4-2009).pdf

75-mumnp-2007-abstract(granted)-(18-8-2010).pdf

75-mumnp-2007-abstract.doc

75-mumnp-2007-abstract.pdf

75-MUMNP-2007-CANCELLED PAGES(23-4-2009).pdf

75-MUMNP-2007-CLAIMS(23-4-2009).pdf

75-mumnp-2007-claims(4-8-2009).pdf

75-mumnp-2007-claims(granted)-(18-8-2010).pdf

75-mumnp-2007-claims.doc

75-mumnp-2007-claims.pdf

75-MUMNP-2007-CORRESPONDENCE(23-4-2009).pdf

75-mumnp-2007-correspondence(4-8-2009).pdf

75-mumnp-2007-correspondence(ipo)-(19-8-2010).pdf

75-mumnp-2007-correspondence(ipo)-(26-8-2009).pdf

75-mumnp-2007-correspondence-others.pdf

75-mumnp-2007-correspondence-received.pdf

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

75-MUMNP-2007-DESCRIPTION(COMPLETE)-(23-4-2009).pdf

75-mumnp-2007-description(granted)-(18-8-2010).pdf

75-MUMNP-2007-DRAWING(23-4-2009).pdf

75-mumnp-2007-drawing(granted)-(18-8-2010).pdf

75-mumnp-2007-drawings.pdf

75-MUMNP-2007-FORM 1(17-1-2007).pdf

75-mumnp-2007-form 2(23-4-2009).pdf

75-mumnp-2007-form 2(granted)-(18-8-2010).pdf

75-MUMNP-2007-FORM 2(TITLE PAGE)-(23-4-2009).pdf

75-mumnp-2007-form 2(title page)-(complete)-(17-1-2007).pdf

75-mumnp-2007-form 2(title page)-(granted)-(18-8-2010).pdf

75-mumnp-2007-form 26(29-7-2009).pdf

75-mumnp-2007-form 26(3-5-2008).pdf

75-mumnp-2007-form-1.pdf

75-mumnp-2007-form-18.pdf

75-mumnp-2007-form-2.doc

75-mumnp-2007-form-2.pdf

75-mumnp-2007-form-3.pdf

75-mumnp-2007-form-5.pdf

75-mumnp-2007-form-pct-ib-301.pdf

75-mumnp-2007-form-pct-ib-304.pdf

75-mumnp-2007-form-pct-isa-237.pdf

75-mumnp-2007-form-pct-separate sheet-237.pdf

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

75-MUMNP-2007-U S PATENT(23-4-2009).pdf

75-mumnp-2007-wo international publication report(4-8-2009).pdf

abstract1.jpg


Patent Number 242194
Indian Patent Application Number 75/MUMNP/2007
PG Journal Number 34/2010
Publication Date 20-Aug-2010
Grant Date 18-Aug-2010
Date of Filing 17-Jan-2007
Name of Patentee ZF FRIEDRICHSHAFEN AG
Applicant Address GEWERBLICHE SCHUTZRECHTE, TORALF HUTTNER, GRAF-VON-SODEN PLATZ 1, 88046 FRIEDRICHSHAFEN,
Inventors:
# Inventor's Name Inventor's Address
1 MARKUS FISCHER 40241 FAIRWAY III RD., MORTHVILLE, MICHIGAN 48167
2 ERIC HOLMES 2030 NORFOLK STREET, ANN ARBOR, MICHIGAN 48103
3 DANIEL DEARING 15811 CENTENNIAL DRIVE, NORTHVILLE, MICHIGAN 48167
PCT International Classification Number F16D3/84
PCT International Application Number PCT/US2005/025980
PCT International Filing date 2005-07-21
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 10/896,498 2004-07-22 U.S.A.