| 摘要 |
OBJECTS To provide a cooling structure for effectively cooling an electromagnetic brake of a phase varying apparatus for an automobile engine MEANS OF ACHIEVING THE OBJECTS In a phase varying apparatus for varying the relative phase between an inner cylinder (20) of a camshaft (2) and a sprocket (12) rotatably mounted on the inner cylinder (20), the phase is varied by energizing an electromagnetic brake (40) adapted to put a braking force on a rotary drum (44) rotatably and coaxially mounted on the inner cylinder (20). A fastening bolt integrally connects the inner cylinder 20 with the body 2a of the camshaft (2). A gap S1 is formed between the head (6a) of the fastening bolt 6 and the inner cylinder (20). A spacer (24) is provided to place the rotary drum (44) at a right axial position on the periphery of the inner cylinder (20). The spacer (24) is provided with grooves (26) (to form oil channels 25) formed in one end face thereof in abutting contact with the head (6a) of the fastening bolt (6). Engine oil is lead to an oil sump (74) formed inside an annular braking section via oil paths (70) formed in the inner cylinder (20) and the oil channels (25). In order to secure a sufficient amount of oil to be stored in the oil sump (74) and supplied to the sliding surfaces for efficient cooling thereof, the length of the bolt head (6a) projecting into is reduced. Thus, an effectively increased amount of oil contributes to efficient cooling of the sliding surfaces. |
