The friction resistance force adds to the torsional resistance force of the spring during application of the pedal and subtracts from the torsional resistance force of {TAIL ~ the spring} upon {HEAD ~ release} of the pedal, whereby to create a hysteresis effect 
The friction resistance force adds to the torsional resistance force of the spring during application of the pedal and subtracts from the torsional resistance force of { TAIL ~ the spring } upon { HEAD ~ release } of the pedal , whereby to create a hysteresis effect
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH