Patent ID: 8387350

Claim:
A grass treatment device comprising: a first roller configured to contact a grass surface; a second roller configured to contact a grass surface; an adjuster configured to allow an adjustment of a distance from said first roller, said adjustment capable of affecting a distance from said grass surface; said adjuster comprising a first shaft operatively connected to said grass treatment device such that said first shaft is rotatable about the longitudinal axis of said shaft, a second shaft operatively connected to said first roller, said first shaft and said second shaft are configured to move relative to each other in threaded engagement following a predetermined thread pitch for longitudinal movement along a main axis of said first shaft and said second shaft and an indicator comprising at least one depression formed in said first shaft and a ball detent mechanism configured to engage with said depression at a predetermined rotational position of the first shaft, the indicator being specifically configured to accurately indicate to a user by a tactile jolt caused by engagement of the ball detent mechanism with said depression a number of predetermined quantized intervals of said distance from said grass surface by virtue of said rotation of said first shaft; and in addition to said indicator, said grass treatment device further comprises a gauge that is configured to visually indicate to said user a distance from said grass surface; said ball detent mechanism and gauge being mutually calibrated based on said thread pitch and on the number of and angular position of said at least one depression such that rotation of said first shaft causes the ball detent mechanism to produce the tactile jolt in synchronism with a predetermined quantized linear displacement measured by the gauge.