Abstract: A loading assembly for a vehicle spindle test fixture includes a belt crank that pivots on a first axis to differentially displace two vertical struts which are attached to a wheel adapter housing in order to apply a braking moment to the vehicle spindle. A lever pivotally supported about a second axis is pivotally joined to the bell crank and is used to displace the bell crank, the vertical struts and the wheel adapter housing to apply a vertical force. A control link controls rotation of the bell crank about the first axis and is pivotally joined to the bell crank about a third axis. A second lever is pivotally supported for movement about the second axis and is pivotally joined to an end of the control link about a fourth axis. When a trailing arm suspension is to be tested, the bell crank, the first lever, the control link and the second lever are arranged to form a non-parallelogram linkage in order to induce a brake axis rotation when a vertical displacement is applied.

Abstract: A loading assembly that permits a lateral force to be applied parallel to an axis of a vehicle spindle includes a support frame and a wheel adapter housing mounted to the vehicle spindle. A loading member is pivotally joined to the support frame at a position spaced apart from the wheel adapter housing on the axis of the spindle. A plurality of spaced apart struts connects the loading member to the wheel adapter housing. An actuator applies a selected force to the loading member, which is transferred as a lateral force to the vehicle spindle. In a first embodiment, an adjustable coupling is provided between the actuator and the loading member to emulate a rolling radius of a tire assembly mounted to the vehicle spindle. In a second embodiment, a second loading member is operably connected to the first-mentioned loading member. A second actuator applies a force to the second loading member to apply a selected moment to the vehicle spindle.

Abstract: A road simulator for testing components of automobiles using a wheel assembly, including a tire that is to be loaded by simulation of actual road forces. A low mass flexible web harness is placed over the tire and has web extensions loaded in tension in at least one lateral direction for simulating forces transmitted to the tire at the tire patch without having any substantial mass applied to the tire. High strength, low mass webs are used for the loading link and harness, such as a nylon, Aramid fibers , or carbon filament materials. The harness permits simulating very closely the actual friction forces on a tire, particularly in relation to lateral direction loading without having test fixture mass affect the test.

Abstract: A vehicle spindle test fixture that permits applying a brake load torque to the spindle or test unit has a loading actuator that will permit high input force levels, while keeping the coupled mass that must be moved during the test operation at a reasonably low level. In testing a vehicle spindle ideally, the mass carried by the test spindle would be equal to the wheel and tire. Because of larger physical sizes, the linkage design problem has become more difficult. The present invention reduces the total coupled mass for brake torque testing by utilizing a unique linkage arrangement that reduces the size of the input used for brake torque.