An improved grass-discharging-passage stirring and cutting mechanism for a rear shaft at a bottom of a lawn mower. Ultra-thin blades are adopted since a grass-discharging passage is very narrow and small while many stirring and cutting rods and blades are used. The blade is firstly placed into mixed buried soil, is subjected to thermal treatment, is scanned by variable-frequency electromagnetic field and laser, and is subjected to electromagnetic co-penetration heat treatment under platinum-rhodium catalysis; then the blade is subjected to organic post-treatment, is heated at a co-penetration turning point of 723 C., and then quenched in organic matter of horse urine; a noise-elimination inner shaft of the rear shaft of the lawn mower is hollow and has a plurality of noise-elimination wedges for facilitating noise elimination and reduction. The improved mechanism may be powered directly by a three-stage planetary retarder connected to an electric motor.

A lawn mower includes: a cutting blade motor that drives a cutting blade; a mode selector that selects one of modes including a normal lawn mowing mode and a grass removal mode in which grass accumulated at the cutting blade is brushed away; and processing circuitry configured to control the cutting blade motor in the mode selected by the mode selector. In the normal lawn mowing mode, the cutting blade motor is controlled so as to rotate in a normal rotation direction at a predetermined rotational frequency or with a predetermined torque. In the grass removal mode, the cutting blade motor is controlled such that the rotational frequency or torque of the cutting blade motor changes more significantly than the rotational frequency or torque of the cutting blade motor in the normal lawn mowing mode, or the cutting blade motor rotates in a reverse rotation direction.

A cutting blade for use in a lawnmower or other cutting device has a contoured leading edge profile that forms a series of protrusions and contoured notches. Each contoured notch has a surface that is smooth and contoured such that air is funneled through the contoured notch by the adjacent protrusions, thereby causing the air to form vortices at the surface of the blade. The formation of the vortices helps the airflow to adhere to the blade surface rather than separate from it, thereby creating a more laminar streamlined flow that merges with air flowing over the opposite side of the blade at the trailing edge. By preventing the airflow from separating from the blade surface over a substantial portion of the blade, turbulence is significantly reduced. Thus, noise generated by the blade is significantly reduced as well. In addition, the blade experiences less drag, and the performance of the blade and lawnmower is generally increased.

An autonomous lawn mower includes a movable cover covering a traveling frame and holding devices holding the movable cover. Each holding device includes a holding shaft and a shaft holding unit. The holding shaft includes a lower half portion and an upper half portion. The shaft holding unit holds the lower half portion accommodated in an accommodating portion of the traveling frame such that the lower half portion can slide in only a horizontal direction. The upper half portion extends through a through hole of the movable cover by extending upward from the traveling frame, thereby holding the movable cover so that the movable cover is vertically displaceable. A coil spring intervenes between a receiving portion and an upper wall of the movable cover. One holding device includes a detector which detects the slide displacement amount of the lower half portion.

A lawn mower includes a housing with an opened bottom, a hollow shaft extending in a vertical direction of the housing and including a lower end positioned within the housing, a cutter blade, flaps provided for at least part of the cutter blade in a manner that the flaps have a flap angle changeable along a horizontal line, an actuator for outputting an output to control the flap angle of the flap, and a transmission mechanism accommodated in the hollow shaft for transmitting the output of the actuator to the flaps.

A multi-segmented lawn mower cutting blade and lawn mower including same. The blade may include a hub defining a rotational blade axis and an elongate arm. The arm includes: an origin connected to the hub; a first segment extending outwardly away from the hub in a first direction from the origin to a distal end of the first segment; and a second segment extending from the distal end of the first segment in a second direction, the second direction being different than the first direction. At least a portion of the arm forms a cutting surface configured to cut vegetation as the blade rotates about the blade axis.

A cutter blade of a lawn mower includes a blade body and flaps. The blade body includes a shape with a sweepback angle inclined in a reverse-rotation direction of the cutter blade. The flap pivotal axis is provided along a blade edge without intersecting with a blade rotational axis. A flap pivotal axis is provided at a position offset from a line perpendicular to the blade rotational axis and in parallel to the pivotal axis, in a rotation direction of the cutter blade.

A self-cleaning, energy efficient blade assembly for use on lawn maintenance equipment and devices is provided. The blade assembly includes a shell and plurality of blades releasably attachable to the shell, wherein the shell is generally bowl-shaped. The blade assembly may also include a stabilizer ring that is positioned immediately adjacent to the shell for added structural rigidity and strength.

A mower blade includes two symmetrical body portions disposed on either side of an axis of rotation, wherein each body portion includes a straight leading edge having a first sharpened edge formed along at least a portion of the leading edge, and a curved trailing edge having a second sharpened edge formed along at least a portion of the trailing edge, so that each body portion tapers to a rounded end.

A cutter blade for a mower is driven to rotate about a vertical axis inside a housing. The cutter blade includes a blade body, a blade portion formed in the blade body and a wind generating portion formed in the blade body on its side opposite in a width direction thereof to the side where the blade portion is formed, the wind generating portion being formed by being raised and bent from the blade body over a predetermined area from an end in a longitudinal direction thereof. At an outer end portion of the wind generating portion in the longitudinal direction of the blade body, there is formed at least one recessed portion recessed more inwards than the remaining portion of the outer end portion.