How long does it take to apply for a patent for utility model? I have submitted it to the patent office for 4 months. It says it has been submitted, but I haven't received the admission notice yet.

If the patent application documents are submitted to the Patent Office, there will be a notice of patent application acceptance (electronic version) on the same day or the next day, including the patent application number and application date.

As for the examination time in the patent office, the patent right can be obtained in 6-8 months after submission to the patent office.