Abstract: A fluid driven tool has an outer housing and an inner motor housing nested in the outer housing and defining a cavity therebetween that has a first end with a first exhaust passageway and a second end with a second exhaust passageway. The inner motor housing has a motor chamber with an inlet port for a fluid driven motor and fluid inlet, and an inlet manifold disposed in the cavity. The inlet manifold has a recessed portion with a surrounding seal that engages the inner motor housing and connects the fluid inlet to the at least one inlet port of the inner motor housing. An inner surface of the outer housing and an outer surface of the inner motor housing have portions that mate upon nesting the inner motor housing in the outer housing and provide reinforced areas for clamping regions of the outer housing located over the reinforced areas.

Abstract: A flow guide configured for insertion in a cavity defined between an outer housing and a nested inner motor housing of a fluid driven tool. The flow guide defines a longitudinal axis and includes at least two longitudinal portions disposed parallel to the longitudinal axis and defining a longitudinal channel therebetween, and a rib being substantially circumferential and connecting the longitudinal portions at points defining a plane substantially transverse to the longitudinal axis. The rib defines a recess that permits fluid communication in the longitudinal channel across the rib.