even if, within the construction as indicated in the claim in the patent specification, there is a part which is different from the products, if (a) this part is not the essential part of the patented invention, (b) the purpose of the patented invention can be achieved by replacing this part with a part in the products and an identical function and effect can be obtained, (c) a person who has an average knowledge in the area of technology where this invention belongs could easily come up with the idea of such replacement at the time of the production of the products, (d) the products are not identical to the technology in the public domain at the time of the patent application of the patented invention or could have been easily conceived at that time by a person who has an average knowledge in the area of technology where this invention belongs, and (e) there were no special circumstances such as the fact that the products had been intentionally excluded from the scope of the patent claim in the patent application process, the products should be regarded as identical with the construction as indicated in the scope of the patent claim and fall within the scope of the technical scope of the patented invention.