How to apply for a divisional application in a US patent application?

The DivisionalApplication)DA in the U.S. patent application is usually when the examiner thinks that the application essentially contains more than two invention claims, and with the consent of the applicant, one of the invention claims is selected for examination. Other claims can be handled separately by divisional application before the mother case is abandoned or authenticated, and the filing date of divisional application is the same as that of the mother case. The purpose of putting forward DA is usually to protect the invention that is not reserved in the parent case claim. Key words: U.S. patent request is unpublished. U.S. patent applications can be requested not to be made public, but the following conditions must be met: U.S. patents must not have prior applications in countries that implement the1August disclosure system; After making a request for non-disclosure, U.S. patents shall not be applicable to countries that implement the 18 month disclosure system.