Trailing Arm Independent Suspension
The trailing Arm is one of the types of Independent Suspensions that maintains constant track & wheel attitude with a slight change in wheelbase & caster angle. It has a coil spring attached to the trailing arm, which connects to the shaft carrying the wheel hub. When the wheel moves up & down, it winds & unwinds the spring. Some designs also use a torsion bar in place of the coil spring.
In sliding-type suspension systems, the stub axle can move up & down as well as rotate inside the frame members. However, track, wheel attitude, and wheelbase remain unchanged throughout the rise and fall of the wheel. On the other hand, the vertical guide suspension system attaches the kingpin directly to the frame’s cross member. Besides, it can slide up & down. Thus, it compresses & expands the springs.
Torque Rod: The Types Of Independent Suspensions
The torque rod, among other independent Suspensions, maintains the correct alignment of the axle with the frame. It also serves to remove all the stresses on the springs. Manufacturers rigidly fix one end of the torque rod to the axle or axle housing. Then, they attach the other end to the frame using a pivoted mounting. Torque Arm is another name for the Torque Rod in these types of Independent Suspensions.
A stabilizer or sway bar is necessary for all independent front-end suspension designs. It reduces the tendency of the vehicle to roll or tip on either side when taking a turn. The use of softer springs & independent front-end suspension increases this tendency to roll or tip.
A stabilizer is a bar of alloy steel with arms at each end. Manufacturers connect these arms to the lower wishbone of the independent suspension or axle. Besides, bush bearings fixed to the frame support it. It is parallel to the cross member.
When both the wheels deflect up or down by the same amount, the stabilizer bar turns within the bearings. However, when only one wheel deflects, then only one end of the stabilizer moves. Thus, it twists the stabilizer bar, which acts as a spring between the two sides of the independent suspension. In this way, the stabilizer reduces heeling or tipping of the vehicle on curves.