| 摘要 |
<p>A drive pulley for a cooling pump or the like of an .engine includes an input (14) for connection to the engine and an output comprising a hollow cylindrical member (4), whose outer surface (6) constitutes a pulley belt engagement surface. The input and output are connected by a transmission system comprising an epicyclic gearset including two or more first planet gears (16), which are connected to respective planet shafts (10) to rotate about the axis thereof and are in mesh with a first sun gear (18). The gearset also includes two or more second planet gears (22), which are connected to rotate with respective first planet gears (16) and are in mesh with a second sun gear (24). The planet shafts (10) are connected to a common carrier (14) which constitutes the input. The first sun gear (18) is connected to the output (4). The transmission system further includes two electric motor/generators (38, 40; 42, 44), the rotors (38, 42) of which are connected to the second sun gear (24) and the output(4), respectively, and the electrical stator connections of which are connected to a controller (46) arranged selectively to control the flow of electrical power between them. The transmission system is at least partially accommodated within the hollow cylindrical member (4).</p> |
