11586354 (B.P.A.I. Feb. 15, 2012)

Ex Parte Flaherty

Board of Patent Appeals and InterferencesFeb 15, 2012

11586354 (B.P.A.I. Feb. 15, 2012)

UNITED STATES PATENT AND TRADEMARK OFFICE ____________ BEFORE THE BOARD OF PATENT APPEALS AND INTERFERENCES ____________ Ex parte ANDREW L. FLAHERTY ____________ Appeal 2010-001078 Application 11/586,354 Technology Center 3600 ____________ Before LINDA E. HORNER, STEVEN D.A. McCARTHY, and GAY ANN SPAHN, Administrative Patent Judges. HORNER, Administrative Patent Judge. DECISION ON APPEAL STATEMENT OF THE CASE Andrew L. Flaherty (Appellant) seeks our review under 35 U.S.C. § 134 of the Examiner’s decision rejecting claims 1-23 under 35 U.S.C. § 103(a) as unpatentable over Kimura (US 5,224,714; iss. Jul. 6, 1993), Heinrich (US 3,744,805; iss. Jul. 10, 1973), and Lipschitz (US 5,143,384; iss. Sep. 1, 1992). We have jurisdiction under 35 U.S.C. § 6(b). We REVERSE. Appeal 2010-001078 Application 11/586,354 2 THE INVENTION Appellant’s claimed invention relates to “hydrodynamic seals for providing a barrier between a housing and a shaft.” Spec. 1, para. [0003]. Claims 1, 8, 17, and 22 are independent. Claim 1, reproduced below, is representative of the subject matter on appeal. 1. A seal assembly comprising: a first seal ring of a generally annular shape and defining radial and circumferential directions; a second seal ring rotatably mounted about an axis of rotation and positioned in facing relation to said first seal ring to define an interface therebetween; a plurality of hydropads formed in one of said first seal ring and second seal ring, each of said hydropads having an inner edge and an outer edge spaced radially outwardly from said inner edge, said inner edges defining an inner circumference of said hydropads and said outer edges defining an outer circumference of said hydropads, and one of said inner circumference and said outer circumference being eccentric relative to said axis of rotation; and an entry point formed on a portion of one of an inner circumference and an outer circumference of one of said first seal ring and said second seal ring for introducing fluid between said first seal ring and said second seal ring, said entry point extending past at least two of said hydropads and less than all of said one of an inner circumference and an outer circumference of one of said first seal ring and said second seal ring. CONTENTIONS AND ISSUES The Examiner determined that “Kimura discloses a seal assembly comprising a first seal ring 4 and a second, rotating seal ring 3[,] . . . [a] Appeal 2010-001078 Application 11/586,354 3 plurality of hydropads 33 . . . [and] [a]n entry point 31 [that] . . . extends along the entire circumference of the ring.” Ans. 3. The Examiner determined that “Lipschitz teaches using entry points 58 formed on an outer circumference of a ring to allow entry of fluid between the faces,” which “provides a lifting force to create a gap between the faces” and “teaches that such entry points do not have to extend the full circumference of the ring to achieve the lifting force.” Id. The Examiner concluded that it would have been obvious to “modify the entry point of Kimura such that it only extends a portion of the circumference since the use of a known technique will yield predictable results.” Id.1 Appellant argues that “combining Kimura with Lipschitz and Heinrich fails to satisfy all of the limitations in the pending claims” and that “[a]bsent Applicant’s disclosure there is no reason to provide an entry point extending past at least two hydropads and less than the entire circumference of the seal ring, as required in claims 1, 8, and 17.” App. Br. 12. Appellant also argues that “[n]one of the cited references disclose or suggest limiting the entry point to extend less than the entire circumference of the seal ring and along a specific portion of the inner or outer circumference relative to where the hydropads extend the least” in the direction of pumping as in independent claim 22. App. Br. 14. 1 The Examiner cites Heinrich to teach “making one of the circumferences eccentric to improve the distribution of medium over the sealing surfaces.” Ans. 4. Appeal 2010-001078 Application 11/586,354 4 The issues presented by this appeal are: Would the combined teachings of Kimura, Lipschitz, and Heinrich have resulted in a seal assembly having an entry point “extending past at least two of said hydropads and less than all of said one of an inner circumference and an outer circumference of one of said first seal ring and said second seal ring” as called for in independent claims 1, 8, and 17? Would the combined teachings of Kimura, Lipschitz, and Heinrich have resulted in a seal assembly having an “entry point extending past at least two of said hydropads along a portion of said one of said inner circumference and said outer circumference of one of said first seal ring and said second seal ring including where said hydropads extend the least in a direction of pumping” as called for in claim 22? ANALYSIS Kimura discloses a non-contacting seal having a rotating sealing ring 3 provided with an outward tapered surface 31 which creates a gap between the rotating sealing ring 3 and a stationary sealing ring 4 that gradually widens and introduces fluid between the sealing rings. Col. 4, ll. 1-9. Kimura further discloses that the rotating sealing ring 3 has a flat surface 32 at the central portion of the sealing surface and spiral grooves 33 at the radially inner region of the sealing surface. Col. 4, ll. 9-12. Lipschitz discloses a “bi-directional, non-contact face seal for sealing, from the ambient, a pressurized fluid in the interior of a housing fitted with a rotatable shaft.” Col. 1, ll. 6-9. Lipschitz teaches that “[c]onventional non- contact seals generally utilize spiral type grooves in the face of the rotor” Appeal 2010-001078 Application 11/586,354 5 and are “designed to function in a unidirectional manner.” Col. 1, ll. 33-35, 37-39. Lipschitz teaches a non-contact seal where “the first and second sealing faces are aligned with and opposed to each other a predetermined operating distance defining a gap, the gap providing a channel for the pressurized fluid to flow toward the ambient” and using a gap positioning means “for producing a gap dependent force to cause the gap between the rotor and stator to stay within a preselected range regardless of the directional rotation of the rotor, thereby providing a bi-directional non- contact seal.” Col. 4, ll. 17-21; col. 5, ll. 43-47. The gap positioning means includes a plurality of radial grooves 58 formed in the rotor sealing face 38 or the stator sealing face 40, where the grooves are symmetrical about a radial line of the sealing face and are spaced from one another so that a plurality of lands 60 are located between the grooves 58. Col. 5, ll. 50-61. As such, Lipschitz teaches replacing conventional spiral grooves on a sealing face with its gap positioning means to create a bi-directional non- contact seal. One of ordinary skill in the art combining the teachings of Kimura and Lipschitz would have not have been led to modify only the outwardly tapered surface 31 of Kimura as proposed by the Examiner. Rather, the teaching in Lipschitz would have led one of ordinary skill to replace Kimura’s tapered surface 31 and spiral grooves 33 with Lipschitz’s gap positioning means. Since Lipschitz’s gap positioning means does not include both an entry point and hydropads, the resulting non-contact seal would not include an entry point extending past at least two hydropads and Appeal 2010-001078 Application 11/586,354 6 that is less than the entire circumference of the seal ring, as called for in claims 1, 8, and 17. The resulting non-contact seal also would not include an entry point extending past at least two of said hydropads along a portion of the circumference of the seal ring includes where the hydropads extend the least in a direction of pumping, as called for in claim 22. The Examiner does not rely on Heinrich to cure this deficiency in the combination of Kimura and Lipschitz. CONCLUSIONS The combined teachings of Kimura, Lipschitz, and Heinrich would not have resulted in a seal assembly having an entry point “extending past at least two of said hydropads and less than all of said one of an inner circumference and an outer circumference of one of said first seal ring and said second seal ring” as called for in independent claims 1, 8, and 17. The combined teachings of Kimura, Lipschitz, and Heinrich would not have resulted in a seal assembly having an “entry point extending past at least two of said hydropads along a portion of said one of said inner circumference and said outer circumference of one of said first seal ring and said second seal ring including where said hydropads extend the least in a direction of pumping” as called for in claim 22. DECISION The decision of the Examiner to reject claims 1-23 is REVERSED. REVERSED nlk