Abstract: An elongated inclined support arm is provided and a horizontal transverse shaft member is journaled from the lower end of the support arm and supports a rotary blade assembly thereon spaced to one side of the support arm. An electric motor is supported from the upper end of the support arm and includes an output shaft paralleling the support arm and extending downwardly along the latter toward the lower end thereof from which a right angle gear transmission is supported having an input shaft projecting toward the upper end of the support arm and an output shaft of which the rotary shaft member comprises a part. A drive shaft extends along the support arm and drivingly connects the motor output shaft to the transmission input shaft and an intermediate portion of the drive shaft is journaled from a corresponding intermediate portion of the support arm.