Abstract: A walk-behind working machine has a machine body and a wheel mounted on the machine body for undergoing rotation to move the walk-behind working machine along a ground surface. A cultivator device is mounted on the machine body for cultivating the ground. A working device attachment is removably connected to the machine body for working the ground. A connection mechanism removably connects the working device attachment to the machine body. The connection mechanism has a pair of link members each pivotally connected at a first end portion thereof to the working device attachment and a control unit for controlling a position of the working device attachment with respect to the ground surface so that when the working operation, the first end portions of the link members are disposed closer to the ground surface than the second end portions of the link members.

Abstract: Connection mechanism includes upper and lower links pivotably connected at one end to a machine body and connected at the other end to a working device, and a control unit for controlling a lower limit position of the device. When the device is in a soil-contacting position prior to initiation of desired work, an end portion of the links adjacent the device is located higher than another end portion adjacent the body. The mechanism further includes a base member connected to the body, an arm vertically pivotably connected to the base member, and a connection member connected to the other end of the links for connecting the device. The device is vertically movable by the arm being vertically pivoted with an engaging member guided along an edge of a window formed in the base member.