DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Claim Objections
Claim 7-9 are objected to because of the following informalities:
Regarding claim 7, the phrases “an end of the electrode tip” and “an end of the electrode rod” should be “the end of the electrode tip” and “the end of the electrode rod” as antecedent basis has already been established in claim 2.
Appropriate correction is required.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 1-11 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Regarding claim 1, the claim language “special-shaped” renders the claim indefinite because it provides no structural or geometric criteria to distinguish a “special” shape with a non-special, conventional shape. Therefore, the use of “special-shaped” is subjective and fails to appraise one of ordinary skill in the art with reasonable certainty as to what shapes are included and excluded within the scope of “special-shaped”.
Regarding claim 2, it recites "the electrode" when a previous claim recites “a pair of electrodes”. There is insufficient antecedent basis for this limitation in the claim and it introduces ambiguity as to whether the limitation applies to one or both electrodes in “the pair of electrodes”.
Claims 3-9, 10 and 11 are rejected to due to the dependency upon rejected-to claims.
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
Claims 1-6 and 11 are rejected under 35 U.S.C. 103 as being unpatentable over Katou et al., US Patent Application Publication No. 20030222054 A1 in view of Bush et al., US Patent Application Publication No. 5015816 A.
Claim 1. Katou teaches a device for resistance spot welding, comprising a pair of electrodes located on a same welding surface of a to-be-welded assembly, wherein the to-be-welded assembly has (Katou, [0003] “The invention relates to a series spot welding method wherein a pair of spaced electrodes is pressed onto a surface of one of two metal plates superimposed on each other and wherein current is caused to flow between the electrodes so as to weld the two metal plates.”)
a symmetry axis, the pair of electrodes are symmetrically arranged on two sides of the symmetry axis, (Katou, [0068] “… the electrode tips 26, 27 are spaced from each other by a predetermined distance with their axes disposed parallel to each other.”)
Katou does not teach an end of each electrode is provided with a special-shaped contact surface, and each special-shaped contact surface is shifted in a direction away from the symmetry axis relative to an electrode axis; wherein the special-shaped contact surface is used for shifting a current density centerline generated by the pair of electrode in a direction away from the symmetry axis relative to the electrode axis, and/or for deflecting a current density of each electrode in a direction away from the welding surface within the to-be-welded assembly.
However, Katou teaches the current of highest intensity flows through the area between the electrodes, as shown by the bold dotted lines in Figs. 6A and 6B, and are responsible for generating a nugget Rn along the inner edge of the electrodes shown in Fig. 6C. Katou also teaches the flat portion of an electrode with more contact area with the workpiece shown in Figs. 7A-7D enlarges the conduction diameter of welding current and reduces the amount of heat generated per unit area. As a result, while the whole electrode leading portion 16b experiences high contact resistance, the highest intensity current indicated by a bold dotted line in Fig. 7A occurs in section 16d where the shortest path connecting the electrodes lie (see Katou [0053]-[0058]). It follows that differing electrode shapes result in different current densities being applied to a workpiece as shown in Figs. 3A-3F where the leading edge portion 26b or 27b of electrode tip 26 or 27 is spherical and forms nugget Nb beside nugget Na as that region exhibits higher contact resistance (see [0088]). In contrast, an electrode tip with a flat portion 56b or 57b shown in Fig 5, Fig. 7A-7D shows that the highest intensity of current flows through section 16d of the peripheral edge 16c (see [0058]).
Accordingly, the deflection of current density applied to the workpiece is a known and inherent result of asymmetrical electrode tips. The fundamental principle of electricity that dictates that the current will preferentially flow through the new offset contact area, is by definition, a deflection of the current density, and is a necessary and unavoidable physical consequence of using the claimed structure. It is elementary that the mere recitation of a newly discovered function or property, inherently possessed by things in the prior art, does not cause a claim drawn to distinguish of the prior art. Additionally, where the Patent Office has reason to believe that a functional limitation asserted to be critical for establishing novelty in the claimed subject matter may, in fact, be an inherent characteristic of the prior art, it possesses the authority to require the applicant to prove that the subject matter shown to be in the prior art does not possess the characteristic relied on (see MPEP § 2112).
Bush teaches an end of each electrode is provided with a special-shaped contact surface, and (Bush, col. 7 line 29 “… a nose portion which is axially offset from the base portion… Specifically, electrode 725 has nose portion 729 axially offset from base portion 727.“)
each special-shaped contact surface is shifted in a direction away from the symmetry axis relative to an electrode axis; wherein (Bush, Figs. 7A, 7B and 7D shows the special-shaped contact surface able to be oriented in a direction relative to the electrode axis.)
the special-shaped contact surface is used for shifting a current density centerline generated by the pair of electrode in a direction away from the symmetry axis relative to the electrode axis, and/or for deflecting a current density of each electrode in a direction away from the welding surface within the to-be-welded assembly. (Bush, Figs. 7A, 7B and 7D shows the special-shaped contact surface offset from the centerline of the electrodes.)
Katou differs from the claimed invention in that Katou does not utilize a special-shaped contact surface on the end of each electrode, however Bush teaches “a specially-shaped welding tip face”. The combination of Katou and Bush teaches substantially the claimed invention. Katou, as modified by Bush to include an asymmetrical contact tip, would also teach current deflection as a result of the asymmetrical contact surface. Accordingly, it would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to simply substitute the electrode tips 26a and 27a as taught by Katou with specially shaped electrodes 725 as taught by Bush. One of ordinary skill in the art would have been motivated to make this combination with a reasonable expectation of success because by using an asymmetrical electrode tip with an offset contact surface that is smaller than the size of the electrode as taught by Bush, shown below, and combining it with a one-sided welding apparatus as taught by Katou, the path of the highest electrical current can be offset from the electrode axis in order to achieve a desired weld nugget. The benefits realized by the selected electrode shape and orientation include “reduction in the amount of current required over more conventional electrodes for a given weld nugget,” weld current characteristics of the invention being significantly improved, extending electrode life, improving operator efficiency, and providing a self-dressing function by mushrooming in a controlled manner for a more consistent quality weld (see col 3 line 6-41) as taught by Bush.
PNG
media_image1.png
408
754
media_image1.png
Greyscale
Claim 2. Modified Katou teaches the device of claim 1, wherein the electrode includes
an electrode tip and an electrode rod, (Katou, Fig. 1 shows electrode tips 26 and 27, and cylinders 24 and 25 which correspond to the claimed electrode rod.)
an end of the electrode tip is detachably sleeved on an end of the electrode rod, (Bush, col. 1 line 27 “Over time, this repeated heating and pressing operation causes breakdown, softening, mushrooming and other deformation of the electrodes. As this occurs, current requirements increase with the enlarged welding tip face contacting the stock until ultimately, replacement is required.”)
The present invention disclosed by Bush is designed to provide a self-dressing function enabling it to mushroom in a controlled manner before replacement is required (see Bush, col. 3 line 6-20). Accordingly, it would have been obvious to one of ordinary skill in the art before the effective filing date of the invention that a system where a tip is designed to eventually be replaced due to wear would require a method of replacement wherein the degraded part, such as the electrode tip, would be connected detachably to the main electrode body to enable replacement. Therefore, the claimed “detachably sleeved” characteristic would be an obvious and necessary implementation required to fully realize the cost-saving benefits of the replaceable, mushrooming tip disclosed in the prior art.
another end of the electrode tip is provided with a boss, and (Bush, Figs. 7A-7F shows the nose portion 729 corresponding with the claimed boss, a small projection on a casting or forging as defined by dictionary.com.)
an end surface of the boss is provided with the special-shaped contact surface. (Bush, Figs. 7A-7F show welding tip face 733 corresponding to the claimed special-shaped contact surface.)
Claim 3. Modified Katou teaches the device of claim 2, wherein the special-shaped contact surface includes
a first contact surface, and (Bush, Figs. 7A-7F shows a convex welding tip curvature 739 corresponding to the first contact surface.)
a geometric center of the first contact surface is located on a side of the electrode axis distal to the symmetry axis. (Bush, Figs. 7A and 7B show the geometric center of the convex welding tip curvature 739 offset from the electrode axis.)
Bush does not explicitly teach distal to the symmetry axis.
However, given Katou’s teaching of two symmetrical electrodes in one-sided or “series” spot welding as well as electrode tip shape influencing the current density applied to a workpiece determining, at least in part, the location of the weld nugget, and given Bush’s teaching of an electrode having a special-shaped contact surface where the geometric center of the convex welding tip curvature 739 is offset from the electrode axis, it would have been obvious to one of ordinary skill in the art to include wherein a geometric center of the first contact surface is located on the side of the electrode axis distal to the symmetry axis. One of ordinary skill in the art would be motivated to adjust the shape or orientation of the electrode in order to apply the highest current to a particular location on the welding surface to achieve a desired weld nugget.
Claim 4. Modified Katou teaches the device of claim 3, wherein the special-shaped contact surface further includes a second contact surface, the second contact surface is connected to a side of the first contact surface proximal to the symmetry axis, and (Bush, Fig. 7A shoulder 737 annotated below corresponds to claimed second contact surface, connected to the welding tip face 733 connected by the concave profile 735 and is positioned proximal to the symmetry axis when the welding tip face 733 is distal to the symmetry axis.)
an area of the first contact surface is larger than an area of the second contact surface. (Bush, Fig. 7A shoulder 737 annotated below has an area smaller than welding tip face 733.)
PNG
media_image2.png
175
297
media_image2.png
Greyscale
Claim 5. Modified Katou teaches the device of claim 4, wherein the first contact surface and the second contact surface are respectively arranged on two sides of the electrode axis, the first contact surface is located on a side distal to the symmetry axis, and the second contact surface is located on a side proximal to the symmetry axis. (Bush, Fig. 7A shows shoulder 737 and welding tip face 733 on opposite ends of the electrode axis. Shoulder 737 may be positioned proximal to the symmetry axis when the welding tip face 733 is distal to the symmetry axis.)
Claim 6. Modified Katou teaches the device of claim 2, wherein a guiding part is arranged on a side of the boss proximal to the symmetry axis, and (Bush, Fig. 7A shows a concave profile 735 on the side of the boss, wherein when the welding tip face 733 is positioned distal to the symmetry axis, concave profile 75 is also distal to the symmetry axis, which corresponds to the claimed guiding part.)
the guiding part is connected between the special-shaped contact surface and an outer wall of the electrode tip; and (Bush, Fig. 7A shows concave profile 735 extends from welding tip face 733 to the edge of the base portion 727 of the electrode tip.)
the guiding part is inclined relative to the electrode axis, and is used for guiding the current density centerline to skew or incline to a side distal to the symmetry axis relative to the electrode axis. (Bush, Fig. 7A shows concave profile 735 has a circular curvature taper relative to the electrode axis to alter the shape of the welding tip and guide the current density away from centerline and towards the offset welding tip face 733 which may be positioned distal to the symmetry axis.)
The concave profile 735 serves to deflect the electrical current away from the center along the electrode axis, towards the offset welding tip face 733. Accordingly, it would have been obvious to one of ordinary skill in the art before the effective filing date of the invention that combining this deflection with the device disclosed by modified Katou enables the application of the electric current onto the desired welding surface proximal to the symmetry axis in order to achieve the desired weld.
Claim 11. Modified Katou teaches a method for resistance spot welding, performed by the device for resistance spot welding of claim 1, comprising: driving a pair of electrodes to travel in parallel along a symmetry axis of a to-be-welded assembly on a welding surface of the to-be-welded assembly, to make the pair of electrodes act on the to-be-welded assembly synchronously, and (Katou, Fig. 11 shows electrodes 26 and 27 parallel along a symmetry axis on a welding surface 30 to weld steel plate Wa to steel plate Wb.)
generate nuggets corresponding to special- shaped contact surfaces of the pair of electrodes in the to-be-welded assembly; wherein (Katou, Figs. 13A-C and 14A-B shows nuggets Na and Nb being formed on the side proximal to the opposite electrode.)
Katou only differs from the claimed invention in that the welding tips used are symmetrical. Bush teaches special shaped welding tips. Therefore, given Katou’s teaching of two symmetrical electrodes in one-sided or “series” spot welding as well as electrode tip shape influencing the current density applied to a workpiece determining, at least in part, the location of the weld nugget, and given Bush’s teaching of an electrode having a special-shaped contact surface, it would have been obvious to one of ordinary skill in the art to include generate nuggets corresponding to special- shaped contact surfaces of the pair of electrodes in the to-be-welded assembly as the deflection of current density applied to the workpiece is a known and inherent result of asymmetrical electrode tips.
a pair of nuggets are provided symmetrically relative to the symmetry axis, and/or, for each nugget, a nugget cross-sectional area in a lower welding plate of the to-be-welded assembly is larger than the nugget cross-sectional area in an upper welding plate of the to-be-welded assembly. (Katou, Fig. 4 shows nuggets Na, Nb and Nc formed symmetrically relative to the symmetry axis. For the purpose of examination, any term “… and/or…” found throughout the application is considered as “… or…”)
Claims 7-9 are rejected under 35 U.S.C. 103 as being unpatentable over Katou et al., US Patent Application Publication No. 20030222054 A1 in view of Bush et al., US Patent Application Publication No. 5015816 A, in further view of Soigneux, FR Patent Application Publication No. 2928854 A1.
Claim 7. Modified Katou teaches the device of claim 2, wherein.
Modified Katou does not teach an end of the electrode tip is provided with a fitting hole arranged axially, and an end of the electrode rod is provided with a connecting part coaxially inserted into the fitting hole.
Soigneux teaches an end of the electrode tip is provided with a fitting hole arranged axially, and (Soigneux, paragraph 4 “This base 30 comprises a blind internal bore 36 opening at an axial end of the base 30. This bore 36 which is coaxial with the longitudinal axis of the base 30…”)
an end of the electrode rod is provided with a connecting part coaxially inserted into the fitting hole. (Soigneux, paragraph 5 “This bore 36 makes it possible to engage the endpiece 3 by force on the conical end of a non-figured electrode holder with a welding clamp also not shown, so as to obtain a hold by wedging of the endpiece. 3 on the electrode holder.”)
Katou, Bush and Soigneux are analogous art because they are related to welding tip geometry. Accordingly, it would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to combine the bore 36 for engaging with an electrode holder as taught by Soigneux with the welding tips of modified Katou. One of ordinary skill in the art would have been motivated to make this combination because due to the high heat and current the welding tips are subjected to, they are prone to distortion and mushrooming which affects the quality of the weld nugget if not replaced or refaced as taught by Bush (see col 2 line 47 – col 3 line 30). Therefore implementing a reliable method of engaging the replaceable electrode tip with the electrode holder by way of a bore coaxial with the longitudinal axis of the base as taught by Soigneux would have yielded predictable results.
Claim 8. Modified Katou teaches the device of claim 7, wherein.
Modified Katou doesn’t teach a side wall of the fitting hole is provided with a sliding groove, a side wall of the connecting part is provided with a sliding block slidably fitted in the sliding groove, and the sliding groove and the sliding block are both provided along the electrode axis.
Soigneux teaches a side wall of the fitting hole is provided with a sliding groove, (Soigneux, Fig. 3 and paragraph 7 “… a groove 35 extending parallel to the axis of the base 30 is machined on the edge of the cylindrical base 30…”)
a side wall of the connecting part is provided with a sliding block slidably fitted in the sliding groove, and (Soigneux, paragraph 7 “Such a welding electrode tip is therefore intended to equip a welding clamp for example of the type comprising two articulated arms one to the other, one being fixed while the second is mobile with respect to the first.”)
the sliding groove and the sliding block are both provided along the electrode axis. (Soigneux, paragraph 4 “This bore 36 which is coaxial with the longitudinal axis of the base 30…”)
Katou, Bush and Soigneux are analogous art because they are related to welding tip geometry. Although Soigneux differs from the claimed invention in that the sliding groove of which the sliding block is fitted against is located on the external cylinder of the welding tip (see Soigneux Fig. 3, groove 35), Soigneux explicitly teaches “Given the asymmetrical nature of the tip, it is necessary to index it in position on the electrode holder. For this a groove 35 extending parallel to the axis of the base 30 is machined on the edge of the cylindrical base 30 to ensure the indexing in position of the tip on the electrode holder.” (see Soigneux, paragraph 7).
Accordingly, it would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to modify the external groove of Soigneux to be an internal groove as claimed. This modification represents a simple and obvious design alternative to a person of ordinary skill in the art, yielding no new or unexpected result.
Claim 9. Modified Katou teaches the device of claim 7, wherein
Soigneux teaches an end surface of the fitting hole is provided with a positioning groove, and (Soigneux, Fig. 3 shows the end surface of the bore 36 has a conical groove, annotated below.)
This bore with conical groove “makes it possible to engage the endpiece 3 by force on the conical end of a non-figured electrode holder with a welding clamp… so as to obtain a hold by wedging of the endpiece 3 on the electrode holder” (see Soigneux, paragraph 5). Accordingly, it would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to implement a reliable method of engaging the replaceable electrode tip with the electrode holder by way of a bore with a conical groove coaxial with the longitudinal axis of the base as taught by Soigneux, yielding predictable results.
PNG
media_image3.png
341
227
media_image3.png
Greyscale
an end of the connecting part is provided with a positioning boss coaxially fitted in the positioning groove; and (Soigneux, paragraph 5 “This bore 36 makes it possible to engage the endpiece 3 by force on the conical end of a non-figured electrode holder with a welding clamp also not shown, so as to obtain a hold by wedging of the endpiece. 3 on the electrode holder.”)
another end of the connecting part is connected with a rod body. (Soigneux, paragraph 7 “Such a welding electrode tip is therefore intended to equip a welding clamp for example of the type comprising two articulated arms one to the other, one being fixed while the second is mobile with respect to the first. These arms are arranged at the end of a robot axis. This robot is programmed to actuate the axes so as to bring the clamp in position vis-à-vis the sheets to be welded…”)
Claim 10 is rejected under 35 U.S.C. 103 as being unpatentable over Katou et al., US Patent Application Publication No. 20030222054 A1 in view of Bush et al., US Patent Application Publication No. 5015816 A, in further view of Kimura et al., US Patent Application Publication No. 4427869 A.
Claim 10. Modified Katou teaches the device of claim 1.
the to-be-welded assembly includes an upper welding plate and a lower welding plate, and (Katou, Fig. 1 shows steel plate Wa and steel plate Wb corresponding to the claimed upper and lower welding plate respectively.
Katou does not teach further comprising a bottom plate and a spacer plate, the upper welding plate and the lower welding plate are laid between the spacer plate and the bottom plate; and a surface of the spacer plate backing toward the upper welding plate is the welding surface.
Kimura teaches further comprising a bottom plate and a spacer plate, (Kimura, Fig. 4 shows the anvils 9 corresponding to the claimed bottom plate, and peripheral portion 3a corresponding to the claimed spacer plate.)
the upper welding plate and the lower welding plate are laid between the spacer plate and the bottom plate; and (Kimura, Fig. 4 shows the outer panel 3 and inner panel 1, corresponding to the claimed lower and upper welding plate respectively, are between anvils 9 and peripheral portion 3’a.)
a surface of the spacer plate backing toward the upper welding plate is the welding surface. (Kimura, Fig. 4 shows the raised portion of the peripheral portion 3’a faces electrodes 10 and 11, the surface making contact with projection 2a of inner panel 1 is the welding surface, which is the target area for electric current and heat is applied.)
Katou, Bush and Kimura are analogous art because they are related to welding methods. Accordingly, it would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to combine the anvils 9 and the peripheral portion 3’a as disclosed by Kimura with the welding plate Wa and Wb setup taught by Katou. One of ordinary skill in the art would have been motivated to make this combination because anvils 9 support the depressing force which will be applied to the panels by the welding electrodes, and peripheral portion 3’a will cause the current to be localized on the path from electrode 10 to peripheral portion 3’a to the raised portion of 1, then through 1a onto the opposite raised portions to be welded under electrode 11, preventing heat generation between outer panel 3 and anvil 9 (see Kimura, col. 3 line 65). Modifying Katou to weld a multi-plate assembly using the method disclosed by Kimura may also provide improved versatility, allowing the Katou the capability of welding different and more complex multi-plate assemblies.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to KRYSTENE NHELLE B MACEDA whose telephone number is (571)272-2380. The examiner can normally be reached M-Th 7:30a-5:00p.
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, Steven Crabb can be reached at (571) 270-5095. 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.
/K.B.M./Examiner, Art Unit 3761
/JUSTIN C DODSON/Primary Examiner, Art Unit 3761