20.7. Corners of installation of forward wheels
Corners of installation of wheels appreciably influence stability of the car, deterioration of tyres and the fuel expense. Distinguish following corners of installation of wheels. Disorder is a corner between a plane of rotation and a wheel vertical. It can be positive if wheels are inclined outside, or negative if wheels are inclined inside. The disorder corner basically influences uniformity of deterioration of tyres of forward wheels. If a corner of disorder of one wheel positive, and another – negative the car will withdraw aside at movement on a straight line;
Convergence – a difference of distances between onboard закраинами the rims measured behind and ahead of wheels at level of their centres. The positive convergence means that wheels are ahead located is more close to each other, than behind, at level of their centres. The negative convergence means that wheels ahead are on большем distance from each other, than behind.
The cross-section inclination of an axis of turn of a wheel is a corner between an axis of an inclination of a rotary fist and a vertical spent through a point of fastening of a wheel in a longitudinal plane of the car.
At the expense of corners of disorder and a cross-section inclination of an axis of turn of a point of a contact of wheels with road settle down more close to an axis of a rotary fist. It supports so-called «a shoulder обкатки». The it is less «a shoulder обкатки», the driving is easier. Besides, blows from roughnesses of a covering are less transferred to a steering.
The corner of a longitudinal inclination of an axis of turn is a corner between an axis of an inclination of a rotary fist and a vertical spent through a point of fastening of a wheel, in a plane, a perpendicular longitudinal axis of the car. The axis concerning which the wheel turns, takes places in space so that its bottom part is inclined forward. Such corner of a longitudinal inclination is called as positive. At positive value of a corner the best stability and stabilisation of operated wheels at rectilinear movement is provided.
Check and adjustment of corners of installation of wheels is necessary for spending on a car repair shop in connection with complexity of the used equipment.