Idler arm

Last updated
Ackermann steering linkage Ackermann steering linkage.png
Ackermann steering linkage
Idler arm for a heavy-duty truck Idler Arm Navistar Truck.jpg
Idler arm for a heavy-duty truck

An idler arm is a pivoting support for a conventional parallelogram steering linkage on some cars and trucks. [1]

The idler arm supports the end of the center link on the passenger's side of the vehicle. The idler arm bolts to the vehicle's frame or subframe. Generally, an idler arm is attached between the opposite side of the center link from the Pitman arm and the vehicle's frame to hold the center link at the proper height. Idler arms are generally more vulnerable to wear than Pitman arms because of the pivot function built into them. If the idler arm is fitted with grease fittings, these should be lubricated with a grease gun at each oil change.

Related Research Articles

<span class="mw-page-title-main">Skid-steer loader</span> Compact heavy equipment with differential steering

A skid loader, skid-steer loader, SSL, or skidsteer is any of a class of compact heavy equipment with lift arms that can attach to a wide variety of buckets and other labor-saving tools or attachments.

<span class="mw-page-title-main">Bicycle brake</span> Braking device for bicycles

A bicycle brake reduces the speed of a bicycle or prevents it from moving. The three main types are: rim brakes, disc brakes, and drum brakes.

<span class="mw-page-title-main">Steering</span> The control of the direction of motion of vehicles and other objects

Steering is the control of the direction of locomotion.

<span class="mw-page-title-main">Strut</span> Structural component designed to resist longitudinal compression

A strut is a structural component commonly found in engineering, aeronautics, architecture and anatomy. Struts generally work by resisting longitudinal compression, but they may also serve in tension.

<span class="mw-page-title-main">Car suspension</span> Suspension system for a vehicle

Suspension is the system of tires, tire air, springs, shock absorbers and linkages that connects a vehicle to its wheels and allows relative motion between the two. Suspension systems must support both road holding/handling and ride quality, which are at odds with each other. The tuning of suspensions involves finding the right compromise. It is important for the suspension to keep the road wheel in contact with the road surface as much as possible, because all the road or ground forces acting on the vehicle do so through the contact patches of the tires. The suspension also protects the vehicle itself and any cargo or luggage from damage and wear. The design of front and rear suspension of a car may be different.

<span class="mw-page-title-main">Independent suspension</span> Vehicle suspension in which each wheel is suspended independently

Independent suspension is any automobile suspension system that allows each wheel on the same axle to move vertically independently of the others. This is contrasted with a beam axle or deDion axle system in which the wheels are linked. "Independent" refers to the motion or path of movement of the wheels or suspension. It is common for the left and right sides of the suspension to be connected with anti-roll bars or other such mechanisms. The anti-roll bar ties the left and right suspension spring rates together but does not tie their motion together.

<span class="mw-page-title-main">Bellcrank</span> Type of crank that changes motion through an angle

A bellcrank is a type of crank that changes motion through an angle. The angle can be any angle from 0 to 360 degrees, but 90 degrees and 180 degrees are most common. The name comes from its first use, changing the vertical pull on a rope to a horizontal pull on the striker of a bell, used for calling staff in large houses or commercial establishments.

<span class="mw-page-title-main">Double wishbone suspension</span> Automotive independent suspension design

A double wishbone suspension is an independent suspension design for automobiles using two wishbone-shaped arms to locate the wheel. Each wishbone or arm has two mounting points to the chassis and one joint at the knuckle. The shock absorber and coil spring mount to the wishbones to control vertical movement. Double wishbone designs allow the engineer to carefully control the motion of the wheel throughout suspension travel, controlling such parameters as camber angle, caster angle, toe pattern, roll center height, scrub radius, scuff, and more.

<span class="mw-page-title-main">Trailing-arm suspension</span> Form of vehicle suspension

A trailing-arm suspension, also referred to as trailing-link, is a form of vehicle suspension. In a motor vehicle it places one or more horizontal arms perpendicular to and forward of the axle on the chassis or unibody, which are connected to the axle or wheels with pivot joint(s). These are typically used on the rear axle or wheels of vehicles, but also found in both front and main landing gear of aircraft.

A swing axle is a simple type of independent suspension designed and patented by Edmund Rumpler in 1903. This was a revolutionary invention in automotive suspension, allowing driven (powered) wheels to follow uneven road surfaces independently, thus enabling the vehicle's wheels to maintain better road contact and holding; plus each wheel's reduced unsprung weight means their movements have less impact on the vehicle as a whole. The first automotive application was the Rumpler Tropfenwagen, later followed by the Mercedes 130H/150H/170H, the Standard Superior, the Volkswagen Beetle and its derivatives, the Chevrolet Corvair, and the roll-over prone M151 jeep amongst others.

<span class="mw-page-title-main">Swingarm</span> Joins the rear wheel of a motorcycle to its body

A swingarm, or "swinging arm" (UK), originally known as a swing fork or pivoted fork, is a single or double sided mechanical device which attaches the rear wheel of a motorcycle to its body, allowing it to pivot vertically. The main component of the rear suspension of most modern motorbikes and ATVs, it holds the rear axle firmly, while pivoting to absorb bumps and suspension loads induced by the rider, acceleration, and braking.

<span class="mw-page-title-main">Pitman arm</span>

A Pitman arm is a shaft that translates rotary or angular movement into linear movement, or vice versa. Pitman arms are commonly found in water pumping windmills, automotive steering systems, and sewing machines.

<span class="mw-page-title-main">Drag link</span>

A drag link converts rotary motion from a crank arm, to a second bellcrank, usually in an automotive steering system.

<span class="mw-page-title-main">Scroll saw</span> Small electric or pedal-operated saw

A scroll saw is a small electric or pedal-operated saw used to cut intricate curves in wood, metal, or other materials. The fineness of its blade allows it to cut more delicately than a power jigsaw, and more easily than a hand coping saw or fretsaw. Like those tools, it is capable of creating curves with edges, by pivoting its table.

<span class="mw-page-title-main">Baker valve gear</span>

After about 1910, the Baker valve gear was the main competitor to Walschaerts valve gear for steam locomotives in the United States. Strictly speaking it was not a valve gear but a variable expansion mechanism adapted to the Walschaerts layout replacing the expansion link and sliding die block. The Baker arrangement used more pivot bearings or pin joints, but avoided the die slip inherent to the expansion link, with the aim of lessening wear and the need for service; it could also facilitate longer valve travel.

<span class="mw-page-title-main">Roberval balance</span>

The Roberval balance is a weighing scale presented to the French Academy of Sciences by the French mathematician Gilles Personne de Roberval in 1669.

<span class="mw-page-title-main">Ball joint</span> Spherical bearing most commonly used in automobile steering mechanisms

In an automobile, ball joints are spherical bearings that connect the control arms to the steering knuckles, and are used on virtually every automobile made. They bionically resemble the ball-and-socket joints found in most tetrapod animals.

<span class="mw-page-title-main">Jaguar independent rear suspension</span> Common component of a number of Jaguar production cars since 1961

Jaguar's independent rear suspension (IRS) unit has been a common component of a number of Jaguar production cars since 1961, passing through two major changes of configuration up to 2006 and last used in the Jaguar XK8 and Aston Martin DB7. This article concentrates on the first generation Jaguar IRS, which firmly established the marque's reputation for suspension sophistication, combining as it did smooth ride with excellent roadholding and low levels of noise, vibration, and harshness (NVH). The two generations overlap in time due to their being used in both full size and sports models that were updated at different times.

A parallelogram steering linkage is called such because like its namesake, the two sides of the linkage run parallel to each other and are equal in distance. This type of steering linkage uses four tie rods, one inner and one outer on each side that are connected by an adjustment sleeve, a center link, an idler arm on the passenger side, and a pitman arm on the driver side. The pitman arm attaches to the steering gear output shaft which is also commonly called the pitman shaft. The pitman arm attaches to the center link and is moved by turning the steering wheel. The center link bar transfers the movement from the pitman arm and pitman shaft to the idler arm on the passenger side. The inner tie rods are mounted to the center link and transfer steering motion to the steering arms and outer tie rods. All of the joints which mount these components are constructed of small ball and socket joints to provide the necessary freedom of movement required to maintain control over the vehicle while it is in motion. The most common type of steering is the parallelogram. The cross-steer and Haltenberger linkage designs are used on some trucks and vans.

References

  1. "What is an idler arm?". dunntire.com. Retrieved 2022-03-29.