US Patent 11027441 Hair cutting device with comb unit recognition

A hair cutting device includes a hair cutting device body and an interchangeable comb unit for defining a hair length after cutting. The hair cutting device body further includes a comb interface for releasable attachment of the comb unit to the hair cutting device body, and a hair length indicator operatively coupled to the comb interface for indicating the hair length to a user. The interchangeable comb unit includes a comb identification member for identifying a hair length associated with the comb unit, and the comb interface includes a comb recognition arrangement being electrically coupled to the hair length indicator. The comb recognition arrangement is configured to sense the comb identification member when the comb unit is connected to the hair cutting device body, and to provide an electronic signal indicative of the hair length associated with the comb unit to the hair length indicator.