Steering mechanism with hydraulic booster, GAZ-3310 - DP, drawings, PP

3.5 Kinematics of longitudinal steering rod

Source Data:

1. Design Spring Length = 1600 mm

2. The spring is symmetrical, the center of the ear is located on the neutral line of the root leaf.

3. Maximum rotation angle of the inner wheel - 45○,

maximum rotation angle of the outer wheel - 34○.

4. The longitudinal angle of the pivot is 5○.

5. The transverse angle of the pivot is 8○.

6. Position of nipple shaft axis and nipple length (219 mm).

By the controllability of the car is understood its ability to accurately follow the turn of the controlled wheels when driving. If the handling of the car is poor, then it spontaneously changes the direction of movement (influence) and, when turning the steering wheel, moves along a curve that does not correspond exactly to the rotation of the steering wheels.

Poor handling of the car requires an increase in muscular work and significant more attention, since a slight delay in turning the steering wheel or its excessive rotation can lead to a skid of the car. At the vertical deformation of springs caused by roughnesses of the road or inertia of podressorenny masses (movement on a curve, braking, etc.), the controllability of the car can be broken owing to discrepancy of kinematics of a pendant and the steering drive and also as a result of changes of angles of installation of pivot axles, a track and the plane of rotation of wheels.

Therefore, for good handling of the car, the kinematic scheme and structural parameters of the suspension must strictly correspond to the kinematics of the steering drive.

Put the spring in the position of a straight root leaf.

We determine the theoretical rolling radius of the spring

Rteor = 0.75· (L - D )/2 = 0.75· (1600 - 86 )/2 = 567.75 mm

(since the spring is symmetrical and fixed to the beam of the front axis by stepladders, we exclude the distance between the stepladders from the calculated spring length).

The center of the spring rolling is located on the neutral line of the core sheet, since the center of the tab of the fixed end of the spring is located on the neutral line of the core sheet, at a distance of 567.75 mm from the core of the spring.

We select the position of the center of the steering pin of the rear end of the longitudinal steering rod at approximately the same distance from the neutral spring line as the axis of the steering pin of the nozzle. Line parallel to neutral spring line is passed through center of steering pin of rear end of longitudinal steering rod. We put the radius of swing of the spring on this line and get a theoretical center of swinging of the nipple finger. On the arc carried out from the practical center of swinging the finger of the nipple. On the arc carried out from the practical center of sucker finger swinging, we lay the centers of the fingers of the rear end of the longitudinal steering rod during the spring to the downed buffer and the sagging spring.

The distance between the centers of the fingers of the rear end of the longitudinal steering rod during the course of the spring to the downed buffer and the sagging spring is measured. With a downed buffer, this distance is 0.436 mm, and with a sagging spring 1.15 mm. The permissible difference between the practical and theoretical arcs at the extreme positions of the spring should not be more than 2 mm, therefore, the position of the center of the steering pin of the rear end of the longitudinal steering rod is selected correctly.

To determine the position of the center of rotation of the steering pin of the rear end of the longitudinal rod in a rear view, a perpendicular to the axis of transverse inclination of the pivot is conducted. We extend this perpendicular to the axis of longitudinal tilt of the pivot. The resulting segments a and b in the top view are set aside from the point O in the respective direction. From the obtained center we pass an arc through the center of the steering pin of the rear end of the longitudinal rod in a top view. On the arc, we set aside the positions of the centers of the steering pin of the rear end of the longitudinal rod corresponding to the turn of the wheel to the right and to the left.

Measure the deflection of the center of the steering pin of the rear end of the longitudinal rod from the position of the center of the steering pin of the rear end of the longitudinal rod corresponding to rectilinear movement. The obtained values ​ ​ of 20.4 mm and 19.7 mm in a rear view are deposited on a horizontal drawn from the center of the steering pin of the rear end of the longitudinal rod. From the ends of these segments, we draw vertically to perpendicular to the axis of transverse tilt of the pivot. The obtained sections c and d correspond to the lifting of the center of the steering pin of the rear end of the longitudinal rod when turning the wheels to the right and to the left.

From the centers of the steering pin of the rear end of the longitudinal rod in the top view, we draw the vertical in the main view to the line drawn through the center of the steering pin of the rear end of the longitudinal rod, parallel to the neutral spring line. From the obtained intersections, we deposit the corresponding segments c and d. The ends of these segments will correspond to the centers of the steering pin of the rear end of the longitudinal rod when turning the wheels to the right and left .

From the centers of the steering pin of the rear end of the longitudinal rod in a top view we draw the arcs R path. To intersection with projection of plane of rotation of center of nozzle pin. From the obtained intersections, we draw the vertical to the main view to the contours drawn from the centers of the steering pin of the rear end of the longitudinal rod. From the centers of the steering pin of the rear end of the longitudinal rod in the main view, we draw arcs through the obtained intersections to the arc along which the center of the nipple pin rotates. Obtained extreme intersections are centers of pin axis when wheels turn to the right and to the left. We connect these centers with the axis of the nipple shaft and measure the angles of rotation of the nipple when turning right and left. The angle of rotation of the nozzle to the right and to the left is less 50○, therefore, there is a margin in the steering mechanism.

We draw an arc from the center of the steering pin of the rear end of the longitudinal rod corresponding to the rectilinear position, and measure the difference. The obtained value of 1.77 mm is due to the fact that the center of the steering pin of the rear end of the longitudinal rod is not on the projection of the plane of rotation of the center of the pin. To obtain the true length of the longitudinal steering rod, it is necessary to Rtract. Add 1.77 mm.

To determine required inclination of pin in lever of swivel cam it is necessary to pass arcs from centers of pin of nozzle through centers of steering pin of rear end of longitudinal rod. Let's put on the resulting horizontal arcs corresponding to the spring moves up and down. From the obtained centers of the steering pin of the rear end of the longitudinal rod, lines are drawn to the corresponding centers of the nipple finger and angles between these lines and contours are measured. The greatest angles turned out with a hanging spring when turning left and with a downed buffer with rectilinear movement. Define the operating range of pin rotation angles in the hinge: 26,83○0,386○5○ (longitudinal angle of pivot tilt) = 21,444○.

Common pivot angle of pin in hinge = 44○ (stock is available).

Determine the angle of pin inclination in the lever of the swivel cam:

21,444○:2 = 10,722○

take the angle of the finger in the lever = 11○.