This case involves a patent application titled "Aluminum-Clad Fiber-Reinforced Composite Core for Overhead Conductors and Its Manufacturing Method." The application was rejected on the grounds of lack of inventiveness during substantive examination. However, our agent contested this decision, arguing that the examiner's method of combining comparative document D1 with comparative document D2 and using reasoning to deduce the claimed invention's technical solution was flawed. Particularly, the notion that technical features central to the invention's innovative points could be inferentially derived represented a fundamental misunderstanding. Therefore, we recommend our client submit a request for re-examination, and provide detailed defense opinions. Finally, the China National Intellectual Property Administration (CNIPA) revoked the rejection decision.

This invention discloses that the composite core includes a fiber core layer composed of multiple fibers and an aluminum-clad layer wrapped around the outer periphery of the fiber core layer. The volume content w of fibers in each composite core is 50% to 70%, the diameter D of the composite core is 2.00 mm to 11.0 mm, the diameter d of the fiber core layer is d= (D² ×w/0.8)^1/2, and the thickness h of the aluminum-clad layer is [D-d]/2, that is, h=[D-d]/2. The technical solution strictly regulates the volume content of fibers in the composite core, the diameter of the fiber core layer, and the thickness of the aluminum-clad layer to improve the comprehensive strength and bending resistance of the composite core, enabling a better comprehensive performance of the composite core. The volume content w, the diameter d, and the thickness h are the key technical parameters for solving the technical problems of this invention. The calculation formula shows that there is a close relationship between the three.

According to our agent's analysis, the goal of this application was to develop an aluminum-clad fiber-reinforced composite core ("composite core 1") with superior strength and bending properties. The mechanical properties of composite core 1 are intrinsically linked to its diameter d and the thickness of the aluminum-clad layer h. If the thickness h of the aluminum-clad layer is larger, the diameter d of the fiber core layer becomes relatively smaller, resulting in lesser strength but better bending performance for the composite core. Conversely, if the thickness h is smaller, the diameter d increases, leading to greater strength but reduced bending performance. Hence, the primary objective of this invention is to determine an optimal diameter d and thickness h for the fiber core layer and aluminum-clad layer, respectively, to achieve a balance between strength and bending performance. Specifically, the volume content w and the outer diameter D of the aluminum-clad fiber-reinforced composite core can be determined in advance. Based on this, research was conducted to determine the suitable values for diameter d and thickness h. It was found that the diameter d shares the following relationship with the known parameters w and D: d=(D²×w/0.8)^1/2. Once the diameter d is ascertained, the thickness h of the aluminum-clad layer can be determined using the formula h=[D-d]/2.

During the substantive examination, the examiner indicated that this invention was not inventive by combining D1 with D2 and reasoning it.

One of the distinct features of this invention compared with D1 is that the diameter d= (D² ×w/0.8)^1/2. The examiner contended in both the first and second office actions that this formula could be transformed to w=0.8*d²/D². The ratio of the volume of the hollow structure (filled with fibers and surrounded by aluminum) to the total volume of the outer diameter is w=d²/D². Therefore, the formula indicates that the filling density ratio of the fiber remains a constant value of 0.8 when the fiber content changes between 50% and 70%, and there are other substances such as 0.2 of other viscous glue or filler. The essence of formula is to set the inner diameter of the fiber core layer within a reasonable range to meet the application requirements only after the diameter of the composite core and the carbon fiber content in the fiber core layer are determined.

We contended that the examiner’s interpretation deviated significantly from the intended purpose of the technical solution of this invention. The examiner initially transformed the formula, presupposing that the diameter d of the fiber core layer and the outer diameter D of the aluminum-clad fiber-reinforced composite core were known parameters. This led to the determination that the fiber's filling density was a fixed value of 0.8, concluding that the invention's formula was merely empirical. This approach clearly contradicts the reality that "the diameter d" is the parameter needing determination.

In our responses to the office action, we repeatedly highlighted that the purpose of this invention was to derive the diameter d and the thickness h from known outer diameter D and volume content w, rather than calculating the volume content w based on the diameter d and the outer diameter D. As the examiner did not see the same technical scheme recorded before the filing date of this invention, the examiner could not retroactively infer the fiber volume content w from the disclosed content. Moreover, the purpose of this invention is not to calculate the volume content w based on the diameter d, the outer diameter D, and the thickness h, but rather to calculate the diameter d and the thickness h based on the known volume content w and outer diameter D. Despite these clarifications, we were unable to persuade the examiner, ultimately leading to the rejection of the invention.

We were of the view that the examiner failed to truly grasp the technical concept and purpose of this invention from beginning to end. Despite our persistent efforts to clarify the invention's objectives and initial intentions, the examiner remained steadfast in his views. It seemed the examiner might have perceived the technical solution as relatively straightforward, leading to a preconceived notion that the invention did not merit authorization, hence the persistent rejection. Given this context, we believed it was imperative to recommend that our client file a re-examination request, especially since the rejected claims held potential for authorization. Therefore, when filing a request for reexamination, we did not make substantive modifications to the claims, and still adopted the previous defense strategies.

Subsequently, the China National Intellectual Property Administration (CNIPA) reassessed this case, acknowledging our re-examination opinions, and smoothly revoked the previous rejection decision. Then the original examination department continued to examine this invention and issued the notification of allowance.

Our agent did not let the examiner's firm rejection stance and seemingly logical arguments cloud our judgment. Instead, we identified flaws in the examiner's reasoning logic. Although not explicitly stated in his reasoning, the examiner appeared to have initially regarded d and D as known parameters before deriving parameter w. This approach was a fundamental departure from our invention. Had our agent not detected this nuance, we might have been swayed by the examiner's line of thought, leading to the belief that the invention lacked inventiveness. Fortunately, convinced of the examiner’s error, our agent steadfastly encouraged the client to pursue re-examination, ultimately securing the patent authorization and ensuring the client's rights were upheld.