First made by Emile Mors in 1899.
Then J.M.M. Truffault created the same type of damping device with a leather washer clamped between two discs, connected to the chassis and the axle.
Shock absorbers are dampers that have an increasing resistance to movement as that movement gets faster.
They are fitted to practically all spring systems and damp out the higher frequency vibrations imparted to the lower frequency action of the main spring. They also resist the rapid and vibrating return of a spring after a bump.
Think of your school ruler pinned over the edge of your desk, you apply force upwards causing a deflection or bending of the ruler, in the perfect world of springs, when you release it, you would want it to drop back to its flat starting position, does it ? no it does not instead in drops to far then comes back up seesawing up and down merrily in every smaller deflections until eventually it stops.
In this example your ruler is acting as an undamped spring (a torsion bar) the behavior which so amuses us as children being exactly what is not wanted from an automotive spring.
Early Automobiles often had no springing, when they did often had no
damping.
When a wheel hits a bump, it tends to move backward (this movement is called compliance).
In a leaf spring system, this movement is absorbed by the twisting of the spring due to the axle force. But the rigidity of the metal-to-metal bearings in an independent suspension did not allow the wheel to move to meet these shocks.
To solve this problem, engineers began to put rubber between the springs and the chassis and then between the blades of leaf springs to prevent them from rusting or squeaking due to the presence of water and grit.
This relative rubbing had an unexpected but desired degree of damping
effect.
First made by Emile Mors in 1899.
Then J.M.M. Truffault created the same
type of damping device with a leather washer clamped between two discs,
connected to the chassis and the axle.
Friction Dampers remained in use for a long time despite their one very large problem. This was Sticktion.
Sticktion - or Starting friction is inherent in all damping systems, meaning that the starting force to make them move is greater than the force required to keep them moving.
Friction damper are notoriously bad for Sticktion, getting the right amount of
damping often required the dampers to be set to a point where starting friction
become obtrusive to the ride quality.
Although they took a long time to become mainstream and finally, De rigueur in Automotive suspension they did exist very early in Automotive development
In 1901, C.L. Horock tried to exploit the resistance to movement of a piston, fitted at its center with a one-way valve and immersed in a fluid :
Horrock's telescopic damper (1901)
In 1905, Louis Renault designed a damper that provided increasing resistance to motion with increasing travel with a double-ended piston moving in a cylinder having its extremities connected to a groove decreasing in depth towards the cylinder ends :
Louis Renault's double ended piston hydraulic damper (1905)
Of course good sense saw out in the end and telescopic fluid dampers have been universally accepted on cars
Others have tried their hand at fluid springing systems such as Citroen and British
Leyland where valves are used to regulate the springing fluid to obtain the damping.