Abstract: An exhaust duct includes a nozzle duct and a cone duct. The nozzle duct includes a first wall forming a first aperture and including a reducing section and an expanding section. The reducing section includes a first edge and a second edge. The expanding section is mounted to the reducing section and includes a third edge and a fourth edge. The reducing section has a circumference that decreases from the first edge to the second edge. The second edge is mounted to the third edge of the expanding section. The expanding section has a circumference that increases from the third edge to the fourth edge. The cone duct includes a second wall forming a second aperture. The nozzle duct is mounted within the second aperture. An air gap is provided between an interior of the second wall and an exterior of the nozzle duct.

Abstract: A dual tine system includes a gear hub including a hub body, right teeth and left teeth, a right gear tooth device mounted to the hub body to rotate the right gear tooth device relative to the gear hub, a left gear tooth device mounted to the hub body to rotate the left gear tooth device relative to the gear hub, a right tine arm, right tines, a left tine arm, and left tines. The right gear tooth device includes a right gear tooth body and a right gear tooth extending from the right gear tooth body to fit within a right valley defined between a pair of the right teeth. The left gear tooth device includes a left gear tooth body and a left gear tooth extending from the left gear tooth body to fit within a left valley defined between a pair of the left teeth.