DESIGN OF SINGLE ENGINE HELICOPTER GEARBOX CONFIGURATION ELIMINATING THE NEED FOR DROP-DOWN GEARBOX IN ENGINE

摘要

3 Claims, 2 Figures 1. OVERVIEW: To invent / design a single engine helicopter gear box eliminating the need for the drop-down gear box in the helicopter engine. 2. DESCRIPTION: In a conventional Main gearbox (MGB) especially finding application in a low weight class single engine helicopter, providing drive to the tail rotor by power tap off from MGB is a technological challenge. The present invention involves the arrangement of gears in Main Gearbox for providing drive to main rotor and drive to accessories. It also includes provision to drive tail rotor from power tap off from MGB through tail drive shaft running directly below the engine in a straight line. This concept has eliminated the need for drop down gearbox in engine. The drive train arrangement is very compact as shown in Fig.-I. 3. CLAIM Main Gearbox (MGB) system for providing drive to the main rotor through 3 stage reduction involving first helical stage, intermediate spiral bevel stage and final planetary stage. The drive to the tail rotor is power tap off from the intermediate stage and tail power take off (TPTO) helical stage. The drive to the accessories arranged in the front side of MGB is through spur gears. The drive to additional hydraulic pump is through bevel stage. The system mentioned above further includes drive to tail rotor from power tap off from MGB . through tail drive shaft running directly below the engine in a straight line. This concept has eliminated the need for drop down gearbox in engine.