| 摘要 |
<p>A fuel pump for supplying fuel to an engine includes a rotary drive shaft (12) having an enlarged portion (18) through which the rotary part of the pump is driven. The pump also has an annular cam ring (17) which is angularly adjustable within the pump housing to vary the timing of fuel delivery. The pump includes a transducer (31) having pole pieces (33, 34) which are located in close proximity to the elongated portion (18) of the drive shaft. The pole pieces form part of a magnetic circuit including a magnet and the pole piece (33) and the adjacent surface of the portion (18) are shaped so that the flux in the magnetic circuit varies in a cyclic manner as the shaft rotates. The pole pieces and magnet are mounted on the cam ring (17) and the transducer includes a former (37) carried by the housing of the pump and upon which is wound a winding. The former surrounds a part of the magnetic circuit and the former and the part of the magnetic circuit are shaped so as to allow angular movement of the cam ring.</p> |
