Leaf spring

leaf springsleaf-sprungleaf-springsemi-elliptic springselliptical springhalf-elliptic springleaf spring suspensionsemi-elliptic leaf springsemi-elliptical springspring
A leaf spring is a simple form of spring commonly used for the suspension in wheeled vehicles.wikipedia
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Spring (device)

springspringsspring-loaded
A leaf spring is a simple form of spring commonly used for the suspension in wheeled vehicles.

Shock absorber

shock absorbersdampersdamper
As a substitute for dampers (shock absorbers), some manufacturers laid non-metallic sheets in between the metal leaves, such as wood.
Spring-based shock absorbers commonly use coil springs or leaf springs, though torsion bars are used in torsional shocks as well.

Beam axle

live axlesolid axlelive rear axle
Unlike coil springs, leaf springs also locate the rear axle, eliminating the need for trailing arms and a Panhard rod, thereby saving cost and weight in a simple live axle rear suspension.
A beam axle's fore & aft location is constrained by either: trailing arms, semi-trailing arms, radius rods, or leaf springs.

Hotchkiss drive

HotchkissHotchkiss layoutHotchkiss live axles
Additional suspension components, such as trailing arms, would usually be needed for this design, but not for "semi-elliptical" leaf springs as used in the Hotchkiss drive.
In the Hotchkiss drive, slip-splines or a plunge-type (ball and trunnion u-joint) eliminate thrust transmitted back up the driveshaft from the axle, allowing simple rear-axle positioning using parallel leaf springs.

Ride quality

rideRide controlsmooth ride
Aside from a weight saving, the main advantage of parabolic springs is their greater flexibility, which translates into vehicle ride quality that approaches that of coil springs.
Early vehicles, like the Ford Model T, with its leaf spring, live axle suspension design, were both uncomfortable and handled poorly.

Carriage

horse-drawn carriagecarriageshorse carriage
Carriages normally have suspension using leaf springs, elliptical springs (in the 19th century) or leather strapping.

Panhard rod

track bartrackbaraxle locating arms
Unlike coil springs, leaf springs also locate the rear axle, eliminating the need for trailing arms and a Panhard rod, thereby saving cost and weight in a simple live axle rear suspension.
This arrangement is not usually used with a leaf spring suspension, where the springs themselves supply enough lateral rigidity, but only with coil spring suspensions.

Car suspension

suspensionrear suspensionsuspension system
A leaf spring is a simple form of spring commonly used for the suspension in wheeled vehicles.
These were often made of low-carbon steel and usually took the form of multiple layer leaf springs.

Unsprung mass

unsprung weightsprung massun-sprung weight
This can lead to handling issues (such as 'axle tramp'), as the flexible nature of the spring makes precise control of the unsprung mass of the axle difficult.
If the vehicle does not have adequate wheel location in the vertical plane (such as a rear-wheel drive car with Hotchkiss drive, a live axle supported by simple leaf springs), vertical forces exerted by acceleration or hard braking combined with high unsprung mass can lead to severe wheel hop, compromising traction and steering control.

Corvette leaf spring

transverse fiberglass mono-leaf springscomposite leaf springsdual pivot mounts with FRP leaf springs
In contrast to many applications of leaf springs in automotive suspension designs, this type does not use the spring as a locating link.

Bogie

trucksbogiestruck
The leaf springs were replaced by coil springs (one per wheel) running vertically rather than horizontally.

Transverse leaf spring front suspension

early Ford carsTransverse leaf spring and solid axle front suspension of early Ford carstransverse leaf springs
The axle receives its vertical and transverse support from a transverse leaf spring (leaf springs were often used for support in more than one direction), and its longitudinal support from fore-aft links sometimes called "radius rods" which are attached (via pivots) to the ends of the axle at their forward end and to the sides of the chassis (again via pivots) at their aft end.

Coil spring

coil springscoilHelical spring
Leaf springs have also replaced traditional coil springs in some trampolines (known as soft-edge trampolines), which improves safety for users and reduces risk of concussion.

Suspension lift

lift kitground clearancelifted
Many trucks are supported by leaf spring suspensions.

Wheel

wheelsroadwheelswheeled
A leaf spring is a simple form of spring commonly used for the suspension in wheeled vehicles.

Vehicle

vehiclesvehicularroad vehicle
A leaf spring is a simple form of spring commonly used for the suspension in wheeled vehicles.

Ellipse

ellipticalellipticeccentricity
Originally called a laminated or carriage spring, and sometimes referred to as a semi-elliptical spring or cart spring, it is one of the oldest forms of springing, appearing on carriages in England after 1750 and from there migrating to France and Germany.

Arc (geometry)

arccircular arcarcs
A leaf spring takes the form of a slender arc-shaped length of spring steel of rectangular cross-section.

Spring steel

SAE 1095springySAE 1075
A leaf spring takes the form of a slender arc-shaped length of spring steel of rectangular cross-section.

Rectangle

rectangularoblongrectangles
A leaf spring takes the form of a slender arc-shaped length of spring steel of rectangular cross-section.

Axle

axlesrear axlehalf shaft
In the most common configuration, the center of the arc provides location for the axle, while loops formed at either end provide for attaching to the vehicle chassis.

Stiction

static coefficient of frictionBreakaway friction
While the interleaf friction provides a damping action, it is not well controlled and results in stiction in the motion of the suspension.

Vehicle frame

unibodyframeladder frame
A leaf spring can either be attached directly to the frame at both ends or attached directly at one end, usually the front, with the other end attached through a shackle, a short swinging arm.

Trailing-arm suspension

trailing armsemi-trailing armtrailing link
Unlike coil springs, leaf springs also locate the rear axle, eliminating the need for trailing arms and a Panhard rod, thereby saving cost and weight in a simple live axle rear suspension. Additional suspension components, such as trailing arms, would usually be needed for this design, but not for "semi-elliptical" leaf springs as used in the Hotchkiss drive.

Austin 7

Austin SevenAustin SevensAustin 7 Ulster
"Quarter-elliptic" springs often had the thickest part of the stack of leaves stuck into the rear end of the side pieces of a short ladder frame, with the free end attached to the differential, as in the Austin Seven of the 1920s.