A height dimension D1 of a head section 4 is smaller than a front-back dimension D2 of the head section 4. The head section 4 has therein a linear actuator 12 as a drive source. Inner blades 13 are coupled to a drive coupling section protruding form an actuator main section. A height dimension of the actuator main section is smaller than a front-back dimension of the actuator main section.