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) a

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) a

Abstract: Compound planetary friction drive comprising an input shaft driving a sun wheel, wherein said sun wheel engages planetary wheels, which planetary wheels are arranged with a first part having a first radius and a second part having a second radius that differs from the first radius, and where-in a ring cylinder is provided that is engaged by the planetary wheels such that the sun wheel is in frictional engagement with the first part of the planetary wheels and the ring cylinder is in frictional engagement with the second part of the planetary wheels, wherein the planetary wheels are hollow and compressible.

Abstract: Compound planetary friction drive comprising an input shaft driving a sun wheel, wherein said sun wheel engages planetary wheels, which planetary wheels are arranged with a first part having a first radius and a second part having a second radius that differs from the first radius, and where-in a ring cylinder is provided that is engaged by the planetary wheels such that the sun wheel is in frictional engagement with the first part of the planetary wheels and the ring cylinder is in frictional engagement with the second part of the planetary wheels, wherein the planetary wheels are hollow and compressible.