Necessary technical features are indispensable technical features to solve technical problems. Here can be an example to illustrate: a class of x has a and b,
B is metal.
If X cannot be without B and B must be metal, then B is a necessary technical feature.
Of course, you can continue to limit it? B is iron or copper. . .
Here, b is a little metal, but b is not iron or copper;
3. See Example 2 above. The last example 2 is a generalized case. If it can't be classified into one type, then at least say what B is, and then B is what. . . Is bitter; In other words, superordinate generalization can contain features that can't solve problems, but it should contain features that can solve problems. Simply put, there can only be more (not necessarily) and not less (definitely);
4. There is a single problem in the technical scheme juxtaposed with exclusive rights. First of all, it should be understood that the criterion of singleness lies in "specific technical characteristics", that is, the characteristics that contribute to the existing technology. If the specific technologies of the juxtaposed technical solutions are different, the exclusive right is also unitary.
Another example: then 2:? B is gold or silver or copper or iron. . . .
Then, if X with A and B has been disclosed in the prior art, where B is iron.
Then the specific technical feature of the technical scheme with B as gold is gold;
. . . Silver. . . . . . . . . . . . . For copper;
These two specific technical features are different, so they lack unity.
= = = = Of course, the example here is very special, but that's basically what it means.
So it is not feasible for you to use "or" to avoid being single.