>> Suspension bracket and steering
>> Suspension bracket geometry
Suspension bracket geometry
Corners of installation of wheels of the car - the general information
Possibility of restriction of vertical movings of a body and reduction of angular fluctuations round cross-section and longitudinal axes is defined by geometry of a suspension bracket and its rigidity.
Forward wheels turn round inclined axes, whose situation is defined by hinges and details of a suspension bracket of the car.
The most important are the kinematic installations of wheel assemblies listed below in relation to a steering and transfer of forces between tires and a paving. It is necessary to remember that corners of installation of wheels considerably influence stability of the car, wear of tires and fuel consumption. Nominal rates subject check and adjustment of corners of installation of wheels of cars considered in the real Management are specified in Specifications of Head the Suspension bracket and a steering.
The corner between the lines formed at section by the horizontal plane of the following planes is called as convergence (convergence):
- Plane of symmetry of the car;
- Rim plane.
Convergence of forward wheels
Convergence can be also defined as a difference of distances between extreme lobbies and back edges of wheel assemblies. Convergence influences straightforwardness of movement of the car and on its controllability, and on front-wheel models compensates resultants kinematic changes of geometry the suspension brackets defined by influence of force of draft. At zero convergence distance between forward edges of wheels equally to distance between their back edges. Normal convergence usually does not exceed inch shares (1 inch = 2.54 cm).
The corner between the lines formed at section by the vertical plane, the perpendicular plane of symmetry of the car of the following planes is called as disorder:
- Plane of symmetry of the car;
- Rim plane.
Corners of installation of a wheel
If the top part of a wheel is rejected from an axis of symmetry of the car outside, disorder is called as negative, and on the contrary. Correctness of adjustment of disorder defines size and the provision of a spot of contact of protectors with a paving and allows to compensate changes in geometry the suspension brackets occurring during commission of turns and at movement of the car on a rough paving.
The kinematic length of a pin represents the shortest distance between the center of an operated wheel and an axis of its turn. For all-wheel drive cars this parameter characterizes influence of forces of draft and forces of resistance a kacheniya on controllability of a vehicle.
The distance between a point of contact of a wheel and a point of intersection of an axis of its turn with a paving on a side view, defining size of the stabilizing moment and influencing course stability of the car and on distribution of forces in a steering is called as a shoulder of stabilization at commission of turns.
Vybegom is called a corner of a longitudinal inclination of an axis of turn of a wheel, i.e., a corner between an axis of turn and a vertical on a side view. Together with a corner of a cross-section inclination of an axis выбег influences change of disorder of wheels at change of an angle of rotation of a steering wheel, and also influences stabilizing moment.
The shoulder of a running in decides as distance between a point of contact of a wheel on a paving and a point of intersection of an axis of its turn with a paving on the front view. The shoulder is considered negative when the last from called above points is between the center and the top part of a wheel. The parameter influences extent of influence of forces of braking on a steering wheel and on size of the stabilizing moment, and, the negative shoulder of a running in increases the last.
The corner of a cross-section inclination of an axis of turn of a wheel represents a corner between an axis of turn of a wheel and a vertical in the plane of cross-section section of the car. Along with vybegy and size of longitudinal shift of an axis of turn influences sensitivity of a steering.
The general check of geometry of a suspension bracket is made at the special stand in the conditions of a specialized workshop.
Back wheels of the car have the suspension brackets defined by geometry which are not giving in to adjustment zero corners of disorder and выбега. The description of procedures of check and adjustment of corners of installation of forward wheels of the car is provided in the Section Check and adjustment of corners of installation of forward wheels.
Conditions of check of corners of installation of wheels
Check of corners of installation of the car demands existence of specially equipped platform. Before the beginning of check it is necessary to make sure of performance of the following conditions:
- Pressure of air in tires corresponds to the nominal;
- Forward wheels are established rectilinearly;
- The car is not loaded, the fuel tank is completely filled;
- Elements of a suspension bracket of the car осажены with effort;
- The steering drive correctly is adjusted;
- Lyufta in wheel bearings, tips of steering drafts and spherical support of a suspension bracket do not leave out of admissible limits;
- Depth of a protector of the tires established on wheels of one axis is identical.