Abstract

It is described a compound planetary friction drive comprising a first sun wheel (2) and planetary wheels (3), wherein said first sun wheel (2) engages said planetary wheels (3), which planetary wheels (3) are arranged with two outer parts (3b) having a first radius (r1) and a central part (3a) having a second radius (r2), wherein the second radius (r2) differs from the first radius (r1) and transition regions (3c) are provided between the outer parts (3b) and the central part (3a), and wherein an outer ring annulus (1) and a central ring annulus (5) are provided that are in driving engagement with the planetary wheels (3), wherein the outer ring annulus (1) has two parts between which, along the length of the planetary wheels (3), the central ring annulus (5) is disposed, wherein the first sun wheel (2) is in frictional engagement with the outer parts (3b) of the planetary wheels (3), said outer parts (3b) of the planetary wheels (3) are in frictional engagement with the parts of the outer ring annulus (1) and the central ring annulus (5) is in frictional engagement with the central part (3a) of the planetary wheels (3), wherein the planetary wheels (3) are both hollow and compressible uninterruptedly along their entire length spanning the outer parts (3b), the transition regions (3c) and the central part (3a).

IPC Classes  ?

• F16H 13/06 - Gearing for conveying rotary motion with constant gear ratio by friction between rotary members with members having orbital motion
• F16H 13/14 - Means for influencing the pressure between the members for automatically varying the pressure mechanically