Abstract: An inner roller 30 (in FIG. 2) for use in an internal-meshing planetary gear construction has its inner-peripheral wall 32 formed into a shape which is brought closer to a regular polygon of n sides (where n denotes an integer of at least 3, and n=3 holds in the illustrated example). Lubricating oil is reserved in clearances H1 defined near the vertices of the regular triangle, and an inner pin 7 is retained in light touch with the three middle points P1-P3 of the respective sides of the regular triangle. Thus, the reservation of the lubricating oil and the retention of the inner pin 7 free from backlash are made consistent, thereby to relieve the backlash of the planetary gear construction and to enhance the durability thereof.

Abstract: An inner roller 30 for use in an internal-meshing planetary gear construction has its inner-peripheral wall 32 formed into a shape which is brought closer to a regular polygon of n sides (where n denotes an integer of at least 3, and n=3 holds in the illustrated example). Lubricating oil is reserved in clearances H1 defined near the vertices of the regular triangle, and an inner pin 7 is retained in light touch with the three middle points P1-P3 of the respective sides of the regular triangle. Thus, the reservation of the lubricating oil and the retention of the inner pin 7 free from backlash are made consistent, thereby to relieve the backlash of the planetary gear construction and to enhance the durability thereof.

Abstract: In fabricating an inner roller for use in an internal-meshing planetary gear construction, the outer periphery of an inner-roller blank 30c is chucked in the state in which depressive forces are equally exerted on the outer periphery in all the directions thereof by a chucking jig 50A, and the inner-peripheral wall of the blank 30c is subjected to a burnishing work in this state. The resulting inner-roller blank 30c is heat-treated in the state in which the depressive chucking is released, whereupon the outer periphery of the blank 30c is finished by grinding. It is accordingly possible to fabricate at low cost the inner roller which can suppress angular backlash owing to a smaller clearance defined between it and a mating inner pin, and which exhibits a high durability and favorable slip characteristics.

Abstract: A plunger for a gob feeder arranged at a forehearth of a glass melting tank furnace which includes a plunger head arranged above an opening of the forehearth, having a hollow space formed therein and, a raising and lowering unit for raising and lowering the plunger head so as to extrude molten glass in the forehearth from the opening when the plunger head is lowered.