I think the most fundamental reason is: "Most dishwasher manufacturers have not yet taken care of the copycat ultrasonic function."
As for the "patented ultrasonic dishwasher" claimed by some dishwasher manufacturers, it is obviously a garbage patent: because industrial ultrasonic cleaning is already an existing technology, the technical purpose of using it in household dishwashers is The technical effects are the same, and according to the provisions of the Patent Law, this is obviously not creative. The lack of inventive step means that the patent can be invalidated. According to the provisions of the Patent Law, an invalidated patent is "deemed to have never existed from the beginning to the end" (it does not mean that it is invalid from the date of invalidation. Instead, an invalidated patent is deemed to have never existed from the beginning. Even if a patent is invalidated within ten years If it is invalidated after 10 years, the patent will be deemed to have ceased to exist ten years ago. This is how the patent law stipulates that all consequences caused by this will be borne by the patentee at that time, and the Patent Office will not bear any responsibility for this. ).
In general, its main significance is to save some detergent, that's for sure. However, if we calculate economics, it may not be economical. Because adding ultrasonic function is also much more expensive.