| 摘要 |
A method of stepping down the speed of a rotary motion from a first speed, supplied to an input shaft (28), to a second speed delivered by an output shaft (26), comprises transmitting said rotary motion to said output shaft (26), via a driven gear (34) of said output shaft (26), the driven gear (34) being helical and having a first helix angle (psiout, from a layshaft arrangement, so as to generate a first axial thrust (F1) of the output shaft (26) in a first axial direction; transmitting said rotary motion to said layshaft arrangement, via a drive gear (44) of said input shaft (28), said drive gear (44) being helical and having a second helix angle (psiin) that is larger than said first helix angle (psiout, from said input shaft (28), so as to generate a second axial thrust (F2) of the input shaft (28) in a second direction, said second direction being substantially opposite to said first direction; and applying said first axial thrust (F1) and said second axial thrust (F2) to the same location of an axially rigid support structure (50), such that said first and second axial thrusts (F1, F2) counter-act and at least partly cancel out in said support structure (50). |
