US Patent 7900428 Edging and trimming apparatus for attachment to lawn mowers

A gear assembly may have a first gear attached to a gear shaft and a second gear attachable to a powered rotating element of a mowing machine. An attachment element may have a shaft hole with the gear shaft rotatably inserted through the shaft hole with one end of the gear shaft positioned in a coupling end of the attachment element. A trimming device with a trimmer tube open at a first end and an end of a shaft of the trimming device with a shaft socket fitting inserted in the coupling end of the attachment element for the shaft socket fitting to engage the gear shaft. An anti-rotating clamp attached adjacent the first end of the trimmer tube for positioning and retention in a clamp recess in a front face of the coupling end to inhibit rotation of the trimmer tube in the coupling end.