From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Page 11 of a document describing the operation of a differential gear, slipping clutch, and planet carrier system for turning a tank.
| Identifier | ExFiles\Box 147\4\ scan0200 | |
| Date | 15th May 1941 guessed | |
| the shaft 27b through a gear train 75 having an odd number of wheels. Thus the shafts 16a and 16b are driven in the same direction through the differential gear 71 and drive the shafts 27a and 27b in opposite directions. The shafts 27a and 27b are coupled by a conventional differential gear 76 of which the planet carrier 77 is driven by a gear wheel 78 which is secured to the bevel wheel 47 of the supplementary drive (see also Figure 2). The bevel wheel 48 (Figure 2) is omitted. The control of the slipping clutch and the two cone clutches is as previously described. With the slipping clutch disengaged and both cone clutches engaged, the bevel wheel 47 cannot rotate, for the reasons already explained. The planet carrier 77 is thus locked so that the differential gear 76 acts as a simple reverse gear to cause the shafts 27a and 27b to turn at the same speed, but in opposite directions, so that the shafts 16a and 16b must also turn at the same speed. To turn the vehicle, one cone clutch is disengaged and the slipping clutch is engaged. The bevel wheel 47 is then driven in one or other direction and drives the planet carrier 77 which, in turn, drives the shafts 27a and 27b in the same direction so as to increase the speed of one of them and decrease the speed of the other so that the tank will be turned. It should be noted that the amount and direction of relative speed of rotation of the shafts 16a and 16b depends solely on the speed and direction of rotation of the planet carrier 77 and is, with the present gear, controlled at all times since the bevel wheel 47 is either locked or driven at a controlled speed in a 11. | ||