Claim Rejections - 35 USC § 102
Claim(s) 1-2 & 4-6 is/are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Izumino, US 7,473,181. Izumino discloses a tripod type constant velocity universal joint (110 comprising:
an outer joint member (14) including track grooves (14a), which extend in a joint axial direction, at three locations in a circumferential direction, each of the track grooves having a pair of roller guide surfaces (14b) arranged to face each other in a joint circumferential direction;
a tripod member (16) including a body portion (16a) having a central hole, three leg shafts (16b) projecting in a radial direction of the body portion, and an intermediate portion (16e) located between the body portion and the leg shafts and having a cross section formed in a curve shape, the cross section including an axial line of each of the leg shafts, the tripod member made of a steel material (inherent, see item 3a below);
a roller (26) mounted on each of the leg shafts; and
an inner ring (22) that is externally fitted to each of the leg shafts and rotatably supports the roller, the roller being movable in an axial direction of the outer joint member along the roller guide surfaces (col. 4, lines 11-13),
the roller and the inner ring forming a roller unit swingable with respect to the leg shafts (see Fig. 4),
the tripod member having a carbon content of 0.23 to 0.44% at a core portion (inherent, see items 3a & 3b below),
each of the leg shafts being provided with a hardened layer of a carburized layer on a
surface of each of the leg shafts (inherent, see item 3a below),
wherein a first region (A) having a radius of curvature R1 in a cross section, which includes the axial line of each of the leg shafts, in a direction orthogonal to the joint axial direction and a second region (see Fig. 1B) having a radius of curvature R2 in a cross section, which includes the axial line of each of the leg shafts, in the joint axial direction are provided in the intermediate portion of the tripod member, and R1 > R2 is satisfied (col. 5, Line 43).
As to claim 2, Fig. 1B shows a connection region is provided between the first region (A) and the second region, the connection region being smoothly connected (see “gradually decreased”) to both the first region and the second region.
As to claim 4, at col. 5, line 61-64, Izumino discloses the ratio R1/PCDspline (see Fig. 2A) equates up to 0.25. Fig. 3 shows the PCDroller guide surfaces 14b is more than twice that of PCDspline which means the ratio R1/PCD14b equates to more than 0.125 (i.e. ≥ 0.085).
As to claim 5, A surface hardness of each of the leg shafts of the tripod member is 653 HV or more (inherent see items 3c & 3e below).
As to claim 6, an internal hardness of the tripod member is 513 HV or more (inherent see items 3d & 3e below).
Claim Rejections - 35 USC § 103
Claim(s) 3 is/are rejected under 35 U.S.C. 103 as being unpatentable over Izumino. Fig. 5 shows the distance from a large-diameter portion of a spline (25) to the first region (A) but Izumino does not expressly disclose the ratio of this distance to PCD is ≥ 0.145. However, it has generally been recognized that the optimization of proportions in a prior art device is a design consideration requiring only routine skill in the art. In re Reese, 290 F.2d 839, 129 USPQ 402 (CCPA 1961). Therefore, it would have been obvious to one of ordinary skill in the art to optimize the proportion of this distance to PCD so that it is ≥ 0.145, as such practice is a design consideration within the skill of the art.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
At the last paragraph on page 139, Universal Joint and Driveshaft Design Manual discloses the spider of a tripod type constant velocity universal joint is made from low carbon alloy steel.
McHone Industries discloses low carbon steel typically consists of 0.04-0.3% carbon.
At the last paragraph on page 139, Universal Joint and Driveshaft Design Manual discloses the surface of a spider of a tripod type constant velocity universal joint is carburized and hardened to a typical Rc60 minimum.
At the last paragraph on page 139, Universal Joint and Driveshaft Design Manual discloses the case depth of a spider of a tripod type constant velocity universal joint is hardened to a typical Rc60 minimum.
At Table 1, Machinery’s Handbook discloses Rc60 equates to 697 HV.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Greg Binda whose telephone number is (571)272-7077. The examiner can normally be reached 9:30-5:30 et.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Matthew Troutman can be reached at 571-270-3654. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
/Greg Binda/Primary Examiner, Art Unit 3679
Prosecution Insights