GB933991A - - Google Patents

Abstract

933,991. Engine turning gear. SCHWITZER CORPORATION. June 26, 1961 [Aug. 8, 1960], No. 22971/61. Pneumatic starting apparatus for an internalcombustion engine comprises a pneumatic motor a shaft driven 13 thereby a pinion gear 48 movable axially. along the shaft for engagement with the engine flywheel gear 52, a housing, a piston 26 slidable within the housing, means mechanically linking the pinion gear and the piston including a drive collar slidable axially on the shaft for axially displacing the pinion gear by the piston, the housing having an air inlet passage 29 therein communicating with a space at one end of the piston whereby upon the introduction of control air under pressure into the inlet passage the piston is moved to cause the pinion gear to engage the flywheel gear and the housing having an air outlet passage 67 communicating with the space accommodating the piston the outlet passage being positioned so as to be uncovered by the piston as it completes the pinion engaging movement thereby allowing control air to flow through the outlet passage only when the pinion gear has engaged the engine flywheel gear. If the push button 93 is actuated control air pressure will be admitted to the line 94. This serves to pressurize the annular chamber 28 and moves the piston 26 to the right. This movement of the piston 26 engages the pins 32 with the channel member 36 and slides the sleeve 37 to the right along the shaft 13. This motion of the sleeve 37 is transferred to the member 41 and consequently the pinion gear 48 through the spring 64. In the event that the teeth of the pinion gear 48 are not properly aligned with the teeth of the ring gear 52 as they engage each other movement of the member 41 will be halted but movement of the sleeve 37 will continue. This relative movement between the sleeve 37 and the member 41 will compress the spring 64 somewhat and because of the spiral splines between the sleeve 37 and the member 41 the pinion gear 48 will be rotated slightly so as to press the pinion teeth into mesh with the ring gear teeth. As the pinion completes its movement to the right the passage or chamber 66 will be uncovered by the piston permitting communication between the passage or chamber 66 and the chamber 28. Control air pressure will thus be caused to exist at the outlet aperture 68 and in the line 96. This causes the valve 89 to open thereby admitting high pressure air to the inlet aperture 84 of the vane type air motor. When the engine starts the over-running clutch 56, 57 prevents transmission of torque from the engine to the shaft 13. The apparatus is suitable for starting compression ignition engines but may also be applied to spark ignition engines.