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Corners of installation of wheels of the car - the general information

Regulation is subject only to the convergence of the front wheels.

The suspension geometry and its rigidity is determined by the possibility of limiting the vertical movements of the body and reduce the angular oscillations about the lateral and longitudinal axes.

The front wheels rotate around the inclined axis, whose position is determined by the hinges and suspension car parts.

The most important is the following kinematic installation of wheel assemblies with respect to the steering wheel and the transmission of forces between the tires and the road surface. The angles of the wheels greatly affect the stability of the car, tire wear and fuel consumption. The nominal value to be checked and wheel alignment described in this guide are given in the vehicle specifications in the early chapters.

Toe-in

vs ??� ???????� ???�???�???�?????? ?????�?�?? d vs - toe angle and - distance between the front edges of the wheels b - The distance between the rear edges of the wheels s - Track b - a - Convergence

Convergence is the angle between the lines formed by the horizontal cross-sectional plane of the following planes:

• The plane of symmetry of the vehicle;
• The plane of the wheel rim.

It may also be determined the difference in distance between the front and rear wheel rim flange.

Convergence affects the straightness of the car and its handling, and front-wheel drive models compensates for the resulting kinematic change the suspension geometry, determines the effect of traction. At zero convergence distance between the front edges of the wheels is equal to the distance between their rear edges.

Wheel alignment

M - The center of the wheel assembly r st - Kinematic length of the trunnion ??� ???????????�???????� ?????�?�?�?????� ?????? ?????????????�?� ?????�?�???� n t - longitudinal displacement of the axis of rotation wheel n - Positive shoulder stabilization ??� ???????� ???????????�?????????? ???�???�?????� ?????? ?????????????�?� ?????�?�???� t - Corner of a longitudinal inclination of the axis of rotation wheel ??� ???????�???�?�?????� ?????�?�?�?????� ?????? ?????????????�?� ?????�?�???� r s - Lateral displacement of the axis of rotation of the wheel r s - Shoulder running ??� ???????� ???�?�???�?�?� ?????�?�?? g - the camber angle ??� ???????� ???????�???�?�???????? ???�???�?????� ?????? ?????????????�?� ?????�?�???� s - The angle of inclination of the transverse axis of rotation wheel

Lounging is the angle between the lines formed by the vertical plane of section perpendicular to the plane of symmetry of the vehicle following planes:

• The plane of symmetry of the vehicle;
• The plane of the wheel rim.

If the upper part of the wheel is inclined to the axis of symmetry of the vehicle, called a negative camber, and vice versa. A correct control of the collapse determines the amount and position of the contact patch with the road surface protectors, and to compensate for changes in suspension geometry that occur during cornering and when driving over uneven pavement.

Kinematic stud length is the shortest distance between the center of steerable wheel and the axis of its rotation.

Shoulder stabilization is the distance between the contact point of the wheel and the point of intersection of the axis of rotation of the road surface in a side of the stabilizing torque determines the magnitude and influence the stability of the vehicle and the distribution of forces in the steering when making turns.

Coasting called pitch in finish turning the wheel axis, i.e., the angle between the vertical axis of rotation and in a side view. At the angle of inclination of the transverse axis of the stick affects the change in the measurement of the camber angle of the steering wheel, as well as stabilizing point.

Kingpin offset is defined as the distance between the point of wheel contact with the road surface and the intersection of its rotation axis with the road surface in a front view. Shoulder considered negative when the last of the above points is between the center and the upper portion of the wheel. The parameter affects the degree of impact deceleration forces on the steering wheel and on the value of stabilizing moment, and, negative kingpin offset increases last.

The angle of inclination of the transverse axis of rotation wheel is an angle between the axis of rotation of the wheels and a vertical cross-sectional plane of the vehicle. Along coasted (and the longitudinal displacement axis of rotation influences the steering sensitivity.

Terms of checking wheel alignment

Check alignment of the car requires a specially equipped rack. Before you start scanning, you must ensure the following conditions:

• Tyre pressure corresponds to the nominal;
• The front wheels are mounted in a straight line;
• The car is loaded, the fuel tank is completely filled;
• Suspension elements Car upset with the effort;
• Steering gear properly adjusted;
• Play in the wheel bearings, tie rods and ball bearings suspension does not go beyond the limits;
• The depth of the tread of tires mounted on the wheels of one same axle.