Shaft-mounted planetary speed-reducing gear unit featuring a balanced, self-aligning and self-distancing ring gear

A shaft-mounted planetary speed-reducing gear unit incorporating a balanced, self-aligning and self-distancing ring gear, and comprising a planet carrier (2) and an output shaft (3), with integral shafts (11) carrying planet pinions (10) which are turned by a sun gear (9) integral with a gear unit input shaft (8) and mesh with the internal teeth of a gear ring (12) fixed to a gear case wherein the gear ring (12) is connected by a pair of generally horizontal diametrically opposed appendages (13) to a pair of generally vertically-disposed hydraulic cylinders (14) located substantially parallel with each other at opposite sides of the gear unit and suspended by way of ball-and-socket joints (15 and 16) between the gear ring and a rigid structure;

• a piston (29) stroking with a barrel (30) of each hydraulic cylinder (14) separates a low pressure oil chamber (31) connected to a low pressure hydropneumatic accumulator (33) by a relative throttle valve (35) and a ball check valve (37), from a high pressure oil chamber (32) connected to a high pressure hydropneumatic accumulator (34) by a relative throttle valve (36) and ball check valve (38);
• the planet carrier (2), cantilevered at the end of the output shaft (3) of a driven machine (4) and equipped with a hub (24), joins with the gear unit input shaft(8) by way of a self-aligning roller bearing (17);
• the gear ring (12), whose internal teeth mesh with planet pinions (10) turning on the intergral shafts (11) by way of self-aligning roller bearings, is fixed to the gear case embodied in two halves:
• a first half (18) at the driven machine side joined to the periphery of the hub (24) of the planet carrier (2) by way of a rotary oil seal (20) and a second half (19) joining with the gear unit input shaft (8) by way of a rotary oil seal (21).