Toothed wheel gear unit for a compressor system

A toothed wheel gear unit for a compressor system having said toothed wheel gear unit inserted in a drive train between a drive unit and a compressor region of the system, said toothed wheel gear unit comprising a transmission housing (1), a transmission input shaft (3) supported in the transmission housing (1), a main gearwheel (5) near the input shaft and drivingly coupled to the input shaft (3), and at least one output shaft (9, 9a), driven by a pinion (7, 19) mounted thereon and leading from the main gearwheel (5) to the compressor region, wherein the improvement comprises:

• the pinion driving at least one output shaft (9a) comprises an externally-toothed sun gear (19) of a planetary gear (15);
• the planetary gear (15) including a planet carrier (23) fixed on the transmission housing (1);
• the planetary gear (15) further including a ring gear (17) rotatably supported on a bearing part (43) that is stationary with respect to the transmission housing (1), the ring gear (17) having inner and outer teeth (29, 27);
• the outer teeth of the ring gear (17) being in engagement with the main gearwheel (5);
• at least one planet gear (21) being rotatably supported on the planet carrier (23) in toothed engagement with the inner teeth (29) of the ring gear (17) and with the teeth of the sun gear (19);
• at least one of the sun gear (19) and said at least one output shaft (9a) being fixed in the axial direction by at least one pressure plate (33) acting on the at least one planet gear (21);
• and
• said at least one planet gear (21) being supported in the axial direction on the planet carrier (23) by an axial force-transmitting bearing arrangement (35).