| 摘要 |
<p>The frictional properties test mechanism (10) comprises a shaft dynamometer (12) connected with a wheel element (14) that is coupled with a braking mechanism (16) for the wheel element (14). The braking mechanism comprises a single rotor (25)/double stator (27) disc brake whose torque tube (29) is attached to a piston housing (40) and torque load cell (54). The piston housing (40), torque armature end plate (41), and torque load cell (54) are mounted by way of bearings (95) within a stationary framework (100), and connected with an oscillatory motion mechanism (18). Located adjacent the stationary framework (100) and connected by arms (24) to the end plate (41) and torque load cell (54) is a pair of spring mechanisms (20) and a pair of hydraulic cylinders (22), which are part of the oscillatory motion mechanism (18). A control and display console (121) operates the dynamometer (12) in order to effect rotary motion of the wheel element (14) and operation of the braking mechanism (16). The oscillatory motion mechanism (18) imparts a slight oscillatory or sinusoidal motion to the end plate (41), torque load cell (54), piston housing (40), torque tube (29) and stators (27) via the hydraulic cylinders (22), spring mechanisms (20), and arms (24). The sinusoidal motion of the stators (27) effects in incremental velocity and incremental torque and enables the determination, via a high speed data acquisition system (190) and computerized data reduction (120, 122, 123), of frictional properties of the brake mechanism (16). A pressure pulse from a generator (130) to the piston housing (40) is used to determine a torque/pressure transfer function, and the variation of frictional properties with temperature is determined by controlling the temperature of the brake friction pair (25, 27) via heater elements (80, 83).</p> |
