The different types of leaf springs come in handy when supporting vehicle load weight and offering shock absorption. Leaf springs attach to the vehicle chassis and help with achieving a smooth ride over bumps.
Leaf springs get their name from their long, arc-shaped strips of spring steel designs. They are attached to the axle and chassis so that they can flex vertically when the car hits a bump.
Further, you will rarely find leaf springs as part of the front suspension system. On the contrary, they are common in rear suspensions of commercial vehicles.
There are different types of leaf springs with unique characteristics and benefits. Todays article takes a closer look at all of them.
Types of leaf springs.
There are different types of vehicle suspension systems that depend on the car’s weight capacity and terrain adaptation.
Further, the types of leaf springs are grouped depending on two major differences;
- According to the number of plates.
- According to the shape of the leaf spring.
Lets start with the simpler one;
Leaf spring types according to the number of plates.
By the number of plates here we mean the amount of long, arc-shaped strips of spring steel in the suspension system spring.
a] Mono leaf springs.
This type of suspension spring has one arc-shaped strip of spring steel. They are characterized by a thick center and they become narrow towards the edges.
Further, they are wider and thicker than the other types of leaf springs. You will find this leaf spring in vehicles that don’t carry heavy loads.
b] Multi leaf springs.
They have two or more strips of spring steel that are on top of each other. The strips of spring steel usually vary in size from the top most strip to the one at the bottom.
Whereby the top most strip of spring steel has the longest length. While the one at the bottom has a shorter length. They are the most common types of leaf springs.
A center bolt holds these plates together. The center bolt is inserted at the thickest point of the strips of spring steel in order to maximize grip.
The multi leaf springs possess a stiffer characteristic. Which makes them suitable parts of the suspension systems that support heavy loads.
But using a vehicle with too many strips of steel will cause a rigid leaf spring suspension effect. Which results to an uncomfortable ride.
c] Parabolic leaf springs.
This type of leaf springs gets the name from their special design. The strips of spring steel have a curve in a parabolic shape.
This type of leaf spring is not common in commercial vehicles. Simply because it’s effectiveness can be seen when it is applied in heavy-duty trailers.
d] Laminated leaf spring.
This is a unique type of leaf spring that stands out from the rest yet some people may confuse it for multi leaf springs. Because it has a number of thin strips of steel that are bonded together.
Another unique characteristic is that it not made from a single piece of material. It isn’t common because of it’s weight handling properties that call for light-duty utilization.
Leaf spring types according to the Shape of the Leaf Spring.
The shape of the leaf springs also determines their different types. With each Shape of the leaf spring holding different benefits for the suspension systems.
In fact, if you are considering a suspension system springs upgrade, you could move from one shape to the other. Depending on the benefits that you are seeking.
a] Quarter-elliptic leaf springs.
In this line of elliptic leaf spring shapes, you find that the quarter elliptic spring is for older vehicle models. Additionally, as the name suggests, this leaf spring is only half of the semi-elliptic leaf springs.
This suspension spring connects to the suspension axle on one end. While on the other end a bolt connects it to the vehicle body frame.
Another name for this leaf spring is cantilever leaf spring.
b] Semi-elliptical leaf springs.
Its the most common type of the leaf springs suspension parts. It has the shape of a bow with one end connecting to a shackle while the other end connects to the vehicle body frame.
The design includes multiple leaf spring steel strips with varying lengths. But those steel strips have the same width or thickness.
Semi-elliptical leaf springs will fit in both the front and rear suspension systems. But they are commonly found in the rear suspension of heavy duty commercial vehicles.
c] Three quarter elliptical leaf springs.
This is a unique leaf spring that combines the semi elliptical and quarter elliptical leaf springs. It attaches to the vehicle’s body frame on one end and to the axle on the other through the quarter part.
Further, the semi elliptical part connects to the body frame with a shackle on one end. Alternatively, the other end connects to the other end attaches to the quarter-elliptical leaf spring.
These types of leaf springs offer extra support to the suspension system. Hence improving vehicle weight balance, handling and ride comfort.
d] Full-elliptical leaf spring.
Its name comes from the combination of two semi-elliptical leaf springs. The shape of this spring is oval because of the two semi elliptical springs joining opposite to each other.
The two semi elliptical leaf springs attach directly to the vehicle’s body on one end. And on the other end, they attach to the vehicle’s axle.
They have the capability of bending up to the same length when compressed. But this suspension leaf spring is rare because it was utilized in old vehicles.
e] Transverse Leaf Spring suspension.
It has a resemblance to the semi-elliptical leaf springs. The similarities are in terms of the leaf spring steel strips that go into the design.
The difference is that the longer leaf spring steel strip is at the bottom. Further, the way this leaf spring is mounted is unique since the mounting is on each wheel.
Further, a U-Bolt secures the middle part of each. Which is the thickest part of the leaf spring steel strips. Additionally, these springs are not common in modern cars. Since their design dates back to older vehicles.
Independent leaf spring suspension.
This is a type of vehicle suspension system whereby the each wheel has a separate leaf suspension. Meaning that the up and down movement that one wheel feels will not go to the opposite wheel.
Since each wheel has a separate leaf spring, the spring supports the weight of the vehicle that goes to that wheel. Further it absorbs the vibrations that are felt on that wheel.
Additionally, each leaf spring attaches to the vehicle’s body frame on one end. While it attaches to the wheel on the other end. There are no attachments that lead to the axle.
Such leaf suspension spring set-ups are very effective at improving vehicle handling and weight distribution balance.