The invention discloses a high-protection direct-acting digital display micrometer, which comprises a measuring head, a propelling
assembly, a display screen and a U-shaped arch, a tube body of a measuring bush is embedded into the display screen, the front section of the measuring bush is embedded into the U-shaped arch, a measuring rod is arranged inside the measuring bush, the front section of the measuring rod is in sliding fit with a positioning sleeve on the front end of the measuring bush, and the rear section of the measuring rod is supported on an adjusting screw which is vertically arranged on the rear section of the measuring bush in a sliding way through two linked guide pillars on two sides of the measuring rod; a main grid is arranged on a main grid seat, and an auxiliary grid is in floating fit with the main grid through a suspension stretching spring leaf which is installed on the tube body of the measuring bush; an electric appliance null-setting mechanism is arranged between the measuring rod and the positioning sleeve; and a large-
pitch lead screw of the propelling
assembly is in floating connection with the measuring rod through a
steel ball. The measuring rod structure and the electric appliance null-setting mechanism in precise positioning on the front end and auxiliary positioning on the rear end are adopted to be matched with a floating auxiliary grid component, so that the movement and
measurement precision of a sensor can be guaranteed; and moreover, the structure is simple, easiness in assembling is realized, and the cost is low.