Turbine wheel containment shroud for a pneumatically powered turbine engine starter motor

Abstract

A containment shroud is attached to the exhaust outlet of a pneumatically powered turbine engine starter for containing the turbine wheel should it be inadvertently disengaged and expelled from the starter motor. The shroud includes a radially flared annularly shaped member attached to and extending outwardly or rearwardly from the exhaust outlet of the motor. A relatively massive central cylindrical member or button is positioned within the annularly shaped member adjacent the outer opening of the annularly shaped member. Four circumferentially spaced, radially outwardly extending bars tie the button to the annularly shaped member and position it adjacent the outer opening of the annularly shaped member. Should the turbine wheel dislodge from the starter motor, it will exit through the starter exhaust opening into the annular member and contact the button and inner surface of the annular member. As it does so, the rotational energy of the wheel will be dissipated via the scrubbing action of the wheel on the button, the bars and the inner surface of the annular member. When the wheel is expelled into the annular member, it will tend to block the outer opening of the annular member. Therefore, a plurality of spaced circumferential openings are located in the annular member adjacent its connection point to the starter exhaust outlet to relieve fluid pressure in a radially outward direction from within the motor if the wheel blocks the opening.

Dependencies are inferred from the claim text.