| 摘要 |
<p>(Case No. 59-3) A hydraulic tensioning device and arrangement which maintains a predetermined amount of tensioning force on an endless drive belt of the vehicle accessories drive system. A hydraulically actuated piston applies a predetermined force to one of the vehicle accessories which is pivotally mounted with respect to the engine to tension the drive belt which is drivingly connected to this vehicle accessory. A self-contained hydraulic fluid supply and pump assembly is mounted in a fixed position on the vehicle engine and has a fluid pressure line connected to the piston for hydraulic actuation of the piston. An idler pulley is rotatably mounted on the fluid supply and pump assembly and is engaged with and driven by the drive belt for actuating the pump to supply hydraulic fluid from the fluid supply to the piston. A coil spring mounted within the piston cylinder applies a portion of the tensioning force on the belt tensioning accessory with the major portion of the tensioning force being applied hydraulically. Check valves regulate the amount of hydraulic force which is applied to the piston and ultimately to the belt by controlling the flow of hydraulic fluid to and from the piston.</p> |
