Send your good work in the knowledge base is simple. Use the form below

Students, graduate students, young scientists who use the knowledge base in their studies and work will be very grateful to you.

Posted on http://www.allbest.ru/

Control mechanisms

1. Steering

The purpose of the steering and the scheme of turning the car

Steering is used to change the direction of the vehicle by turning the front steer wheels. It consists of a steering gear and a steering gear. On heavy-duty trucks, a power steering is used in the steering system, which makes it easier to control the car, reduces tremors on the steering wheel and increases driving safety.

Vehicle turning scheme

The steering mechanism serves to increase and transfer to the steering gear the effort applied by the driver to the steering wheel. The steering mechanism converts the rotation of the steering wheel into translational movement of the drive rods, causing the steering wheels to turn. In this case, the effort transmitted by the driver from the steering wheel to the steering wheels increases many times.

The steering drive, together with the steering gear, transfers the control force from the driver directly to the wheels and thereby rotates the steered wheels at a given angle.

To make a turn without side sliding of the wheels, all of them must roll along arcs of different lengths described from the center of rotation O see fig. In this case, the front steered wheels must turn at different angles. The inner wheel with respect to the center of rotation should turn through the alpha-B angle, the outer wheel - through a smaller alpha-H angle. This is ensured by a trapezoidal connection of the rods and steering levers. The base of the trapezium is the beam 1 of the front axle of the car, the sides are the left 4 and right 2 pivot levers, and the top of the trapezoid is formed by the transverse link 3, which is pivotally connected to the levers. The pivot pins 5 of the wheels are rigidly attached to the levers 4 and 2.

One of the pivot levers, most often the left lever 4, is connected to the steering mechanism through a longitudinal rod 6. Thus, when the steering mechanism is actuated, the longitudinal rod, moving forward or backward, causes both wheels to turn at different angles in accordance with the steering pattern ...

steering mechanism control car

Steering circuits

The location and interaction of steering parts that do not have an amplifier can be seen in the diagram (see figure). Here, the steering mechanism consists of a steering wheel 3, a steering shaft 2 and a steering gear 1 formed by the engagement of a worm gear (worm) with a toothed stop, on the shaft of which the bipod 9 of the steering drive is attached. The bipod and all other parts of the steering: the longitudinal rod 8, the upper arm of the left pivot pivot 7, the lower arms 5 of the left and right pivot pins, the transverse rod 6 constitute the steering gear.

The rotation of the steered wheels occurs when the steering wheel 3 rotates, which, through the shaft 2, transfers the rotation to the steering gear 1. In this case, the gear worm, which is in engagement with the sector, begins to move the sector up or down along its groove. The sector shaft begins to rotate and deflects the bipod 9, which with its upper end is pushed onto the protruding part of the sector shaft. The bipod deflection is transmitted to the longitudinal thrust 8, which moves along its axis. The longitudinal rod 8 is connected through the upper arm 7 with the pivot pin 4, so its movement causes the left pivot pin to rotate. From it, the turning force through the lower levers 5 and the transverse rod 6 is transmitted to the right pivot. Thus, both wheels turn.

The steered wheels are turned by the steering system through a limited angle of 28-35 °. The restriction is introduced in order to prevent the wheels from touching the suspension parts or the car body when turning.

The design of the steering system is very dependent on the type of suspension of the steering wheels. With a dependent suspension of the front wheels, in principle, the steering scheme shown in (Fig. A) is preserved, with an independent suspension (Fig. 6), the steering drive becomes somewhat more complicated.

2. The main types of steering mechanisms and drives

Steering gear

It allows the steering wheels to be steered with little effort on the steering wheel. This can be achieved by increasing the steering gear ratio. However, the gear ratio is limited by the number of revolutions of the steering wheel. If you choose a gear ratio with the number of revolutions of the steering wheel more than 2-3, then the time required to turn the car significantly increases, and this is unacceptable due to driving conditions. Therefore, the gear ratio in the steering mechanisms is limited to 20-30, and to reduce the effort on the steering wheel, an amplifier is built into the steering mechanism or drive.

The limitation of the gear ratio of the steering gear is also associated with the property of reversibility, that is, the ability to transfer reverse rotation through the gear to the steering wheel. With large gear ratios, friction in the gearing of the mechanism increases, the property of reversibility disappears and self-return of the steered wheels after turning into a straight-line position is impossible.

Steering mechanisms, depending on the type of steering gear, are divided into:

Worm gear,

Screw,

· Gear.

The steering gear with a worm-type transmission - the roller has a worm as a driving link, fixed on the steering shaft, and the roller is mounted on a roller bearing on the same shaft with a bipod. To make full engagement at a large angle of rotation of the worm, the worm is cut along an arc of a circle - a globoid. Such a worm is called globoid.

In the screw mechanism, the rotation of the screw connected to the steering shaft is transmitted to the nut, which ends with a rack meshed with the toothed sector, and the sector is installed on the same shaft with the bipod. Such a steering mechanism is formed by a screw-nut-sector steering gear.

In gear steering mechanisms, the steering gear is formed by cylindrical or bevel gears, which also include a gear-rack transmission. In the latter, the cylindrical gear is connected to the steering shaft, and the rack, meshed with the gear teeth, acts as a lateral thrust. Rack and pinion gears and worm-roller type gears are mainly used on passenger cars, since they provide a relatively small gear ratio. For trucks, steering gears of the worm-sector and screw-nut-sector type are used, equipped either with amplifiers built into the mechanism, or with amplifiers placed in the steering gear.

Steering drive

The steering gear is designed to transfer the power from the steering mechanism to the steered wheels, while ensuring their rotation at unequal angles. Steering drive designs differ in the arrangement of the levers and rods that make up the steering linkage in relation to the front axle. If the steering linkage is in front of the front axle, then this design of the steering drive is called the front steering linkage, with the rear positioning - the rear linkage. The design of the front wheels' suspension has a great influence on the design and layout of the steering linkage.

With a dependent suspension, the steering gear has a simpler design, since it consists of a minimum of parts. The transverse tie rod in this case is made integral, and the bipod swings in a plane parallel to the longitudinal axis of the vehicle. You can also make a drive with a bipod swinging in a plane parallel to the front axle. Then there will be no longitudinal thrust, and the force from the bipod is transmitted directly to the two transverse rods associated with the wheel journals.

With independent suspension of the front wheels, the steering drive circuit is structurally more complicated. In this case, additional drive parts appear, which are not in the scheme with dependent wheel suspension. The design of the tie rod is changed. It is made split, consisting of three parts: the main transverse rod 4 and two side rods - left 3 and right 6. The pendulum arm 5 serves to support the main rod 4, which in shape and size corresponds to the bipod 1. Connection of the side transverse rods with swivel levers 2 trunnions and with the main transverse link is made using hinges that allow independent movement of the wheels in the vertical plane. The considered steering drive scheme is used mainly on passenger cars.

The steering drive, being a part of the car's steering control, provides not only the ability to turn the steered wheels, but also allows the wheels to oscillate when they hit the bumps in the road. In this case, the drive parts receive relative displacements in the vertical and horizontal planes and, when turning, transmit the forces that turn the wheels. The connection of parts for any drive scheme is carried out using ball or cylindrical hinges.

3. Design and operation of steering mechanisms

Steering gearwith a worm-roller type transmission

It is widely used in cars and trucks. The main parts of the steering mechanism are the steering wheel 4, the steering shaft 5, installed in the steering column 3 and connected to the globoid worm 1. The worm is installed in the steering gear housing 6 on two tapered bearings 2 and is meshed with a three ridge roller 7, which rotates on ball bearings on the axle ... The axis of the roller is fixed in the forked crank of the bipod shaft 8, resting on the bushing and the roller bearing in the crankcase 6. The engagement of the worm and the roller is adjusted by the bolt 9, into the groove of which the stepped shank of the bipod shaft is inserted. Fixation of a given gap in the engagement of the worm with the roller is made by a shaped washer with a pin and a nut.

Steering gear of the car GAZ-53A

The steering gear case 6 is bolted to the frame side member. The upper end of the steering shaft has tapered splines, on which the steering wheel is fitted and fastened with a nut.

Steering gear with screw-nut transmissiona - rail - sector with amplifier

It is used in the steering of a ZIL-130 car. The power steering is structurally combined with the steering gear into one unit and has a hydraulic drive from pump 2, which is driven by a V-belt from the crankshaft pulley. The steering column 4 is connected to the steering mechanism 1 through a short propeller shaft 3, since the axes of the steering shaft and the steering mechanism do not coincide. This is done to reduce the overall dimensions of the steering.

Steering gear of a car

The following illustration shows the structure of the steering gear. Its main part is the crankcase 1, which has the shape of a cylinder. Inside the cylinder there is a piston - a rack 10 with a nut 3 rigidly fixed in it 3. The nut has an internal thread in the form of a semicircular groove, where balls are laid 4. By means of balls, the nut is engaged with the screw 2, which, in turn, is connected to the steering shaft 5. В the upper part of the crankcase is attached to the body 6 of the hydraulic booster control valve. The control element in the valve is a spool 7. The actuator of the hydraulic booster is a piston - rack 10, which is sealed in the crankcase cylinder by means of piston rings. The piston rack is threaded with the toothed sector 9 of the shaft 8 of the bipod.

Steering device with built-in hydraulic booster

The rotation of the steering shaft is converted by the transmission of the steering mechanism into the movement of the nut - piston along the screw. In this case, the rack teeth turn the sector and the shaft with the bipod attached to it, due to which the steering wheels turn.

When the engine is running, the power steering pump supplies oil under pressure to the power steering, as a result of which, when making a turn, the power steering develops additional force applied to the steering gear. The principle of operation of the amplifier is based on the use of oil pressure on the ends of the piston - rack, which creates additional force that moves the piston and facilitates turning of the steered wheels. [ 1 ]

Vehicle turning scheme

One of the most important vehicle systems from the point of view of road safety is the steering system, which ensures its movement (turning) in a given direction. Depending on the design features of wheeled vehicles, there are three ways of turning:

By turning the steered wheels of one, several or all axles

By creating a difference in the speeds of the uncontrollable wheels of the right and left sides of the cars (turning to the "caterpillar")

Mutual forced rotation of the links of the articulated vehicle

Multi- or two-link wheeled vehicles (road trains), consisting of a wheeled tractor, a trailer (trailers) or a semitrailer (semitrailers), turn only with the steered wheels of a tractor or a tractor and a trailed (semitrailer) link.

The most widespread are the schemes of wheeled vehicles with rotary (steerable) wheels.

With an increase in the number of pairs of steered wheels, the minimum possible turning radius of the machine decreases, i.e., the maneuverability of the vehicle improves. However, the desire to improve maneuverability through the use of front and rear steered wheels significantly complicates the design of the drive to control them. The maximum turning angle of the steered wheels usually does not exceed 35 ... 40 °.

Turning schemes for two-, three- and four-axle wheeled vehicles with steerable wheels

Rice. Turning schemes for two-, three- and four-axle wheeled vehicles with steerable wheels: a, b - front; in - front and back; f, g - the first and second axes; h - all axes

Turning schemes of a wheeled vehicle with non-steer wheels

Rice. Turning schemes for a wheeled vehicle with non-steer wheels:

a - with a large turning radius; b - with zero radius; О - center of rotation; V1, V2 - speed of movement of the lagging and leading sides of the car

By turning the steered wheels of the vehicle, the driver makes it move along a trajectory of a given curvature in accordance with the angles of rotation of the wheels. The greater the angle of their rotation relative to the longitudinal axis of the machine, the smaller the turning radius of the vehicle.

The "crawler" turning scheme is used relatively rarely and mainly on special vehicles. An example is a wheeled tractor with fixed wheels and a transmission that rotates the tractor practically around its geometric center. The domestic lunokhod, which has an electric motor-wheel with the 8CH8 formula, has the same turning scheme. The turning of such vehicles is carried out at unequal speed of the wheels of different sides of the machine. Such steering control is most easily ensured by stopping the supply of torque to the side of the machine lagging behind when turning, the speed of the wheels of which decreases due to their braking. The greater the difference in the speed of the running V2, i.e. external with respect to the center of rotation (point O), and lagging V1 (internal with respect to the center of rotation) sides of the machine, the smaller the radius of its curvilinear movement. Ideally, if the speeds of all wheels of both sides are equal, but directed in opposite directions (V2 = -V1), we will get a zero turning radius, that is, the car will turn around its geometric center.

The main disadvantages of vehicles with non-steer wheels are the increased power consumption for cornering and greater tire wear compared to vehicles with steer wheels.

Articulated vehicle turning schemes for engineering tractors. These machines have good maneuverability (their minimum turning radius is smaller than that of conventional cars with the same base and better adaptability to road irregularities (due to the presence of hinges in the towing device and the towing link), and also provide the ability to use large diameter wheels , which improves the passability of these vehicles.

Posted on Allbest.ru

Introduction

Every year the car traffic on the roads of Russia is steadily increasing. In such conditions, the design of vehicles that meets modern traffic safety requirements is of paramount importance.

Driving safety is greatly influenced by the steering design, as the most important factor in the interaction of the driver with the road. To improve the characteristics of the steering, various types of amplifiers are added to its design. In our country, power steering is used almost only on trucks and buses. Abroad, more and more passenger cars have power steering, including cars of medium and even small classes, since power steering has an undeniable advantage over conventional ones, and provides much greater comfort and safety.

1.1 Basic data for steering design

Chassis parameters depend on the type of body, the location of the engine and gearbox, the mass distribution of the vehicle and its external dimensions. In turn, the steering scheme and design depend both on the parameters of the entire vehicle and on the decisions made on the scheme and design of other chassis and drive elements. The steering layout and design are determined early in the vehicle design phase.

The basis for the choice of the control method and the steering layout diagram are the characteristics and design solutions adopted at the stage of preliminary design, such as: maximum travel speed, base dimensions, track dimensions, wheel formula, axle load distribution, minimum turning radius of the vehicle.

In our case, it is necessary to design the steering for a small class passenger car with a front transverse engine and front drive wheels.

Initial data for calculations:

To assess the forces and moments acting in the steering, information is also required on the main kinematic points of the front suspension, as well as the angles of the steering wheels. Usually, these data become determined as the synthesis of the kinematic suspension scheme is completed at the end of the assembly stage and are refined (corrected) at the stage of the car's fine-tuning. For initial, approximate calculations, data on the angles of the pivot axis and the size of the running arm are sufficient. In our case, these are:

It should be noted that the accepted value of the minimum turning radius of the vehicle, which characterizes its maneuverability, is, apparently, the minimum possible for front-wheel drive vehicles of this class. The limiting factor here is the maximum possible angle in the constant velocity joints, which are used to transfer torque from the power unit to the front wheels. Analysis of the data on the turning radius of small cars produced in the 70-80s shows that its value lies in the range of 4.8-5.6 m. Further reduction of this indicator is possible only through the use of all-wheel steering.

To estimate (calculate) the moment on the steering wheel and the forces acting in the steering, it is necessary to know the axle load. For front-wheel drive vehicles, the average axle weight distribution is (%):

1.2 Purpose of steering. Primary requirements

Steering is a set of devices that rotate the steered wheels of a car when the driver acts on the steering wheel. It consists of a steering gear and a steering gear. To facilitate turning the wheels, an amplifier can be built into the steering gear or drive. In addition, a shock absorber can be integrated into the steering system to improve driving comfort and safety.

The steering gear is designed to transfer power from the driver to the steering gear and to increase the torque applied to the steering wheel. It consists of a steering wheel, steering shaft and gearbox. The steering gear is used to transfer the force from the steering mechanism (gearbox) to the steered wheels of the car and to ensure the required ratio between the angles of their rotation. The shock absorber compensates for shock loads and prevents steering wobble.

The task of the steering is the most unambiguous transformation of the steering wheel angle into the wheel angle and the transmission of information about the vehicle movement state to the driver through the steering wheel. The steering structure must provide:

1) Ease of control, assessed by the effort on the steering wheel. For cars without an amplifier when driving, this effort is 50 ... 100 N, and with an amplifier 10 ... 20 N. According to the project OST 37.001 "Vehicle handling and stability. General technical requirements", which was put into effect in 1995, vehicles of category M 1 and M 2 must not exceed the following values.

The standards for the effort on the steering wheel given in the draft OST correspond to the enacted UNECE Regulations No. 79;

2) Rolling of the steered wheels with minimal side slip and slip when turning the car. Failure to comply with this requirement leads to accelerated wear of tires and a decrease in vehicle stability while driving;

3) Stabilization of the turned steered wheels, ensuring their return to a position corresponding to straight-line movement with the steering wheel released. According to the project OST 37.001.487, the return of the steering wheel to the neutral position should occur without hesitation. One transition of the steering wheel through the neutral position is allowed. This requirement is also aligned with UNECE Regulation No. 79;

4) Informativeness of the steering, which is ensured by its reactive action. According to OST 37.001.487.88, the effort on the steering wheel for a car of category M 1 should increase monotonically with an increase in lateral acceleration up to 4.5 m / s 2;

5) Prevention of transmission of shocks to the steering wheel when the steered wheels hit an obstacle;

6) Minimum joint clearances. Evaluated by the angle of free rotation of the steering wheel of a car standing on a dry, hard and level surface in a position corresponding to straight-line movement. According to GOST 21398-75, this gap should not exceed 15 0 with the presence of an amplifier and 5 0 - without an amplifier of steering;

7) Absence of self-oscillations of the steered wheels when the car is operating in any conditions and in any driving modes;

8) The angles of rotation of the steering wheel for vehicles of category M 1 must be within the limits established by table. :

In addition to these basic functional requirements, the steering must provide a good "road feel", which also depends on:

1) a sense of precision control;

2) smoothness of the steering;

3) efforts on the steering wheel in the zone of rectilinear movement;

4) the feeling of friction in the steering;

5) sensation of viscosity of the steering;

6) the accuracy of the centering of the steering wheel.

At the same time, depending on the speed of the vehicle, various characteristics are of the greatest importance. In practice, at this stage of the design process, it is very difficult to create an optimal steering design that would provide a good "road feel". Usually this problem is solved empirically, based on the personal experience of designers. The final solution to this problem is provided at the stage of fine-tuning the car and its components.

Special requirements are imposed on the reliability of the steering, since when it is locked, when any of its parts is destroyed or loosened, the car becomes uncontrollable, and an accident is almost inevitable.

All stated requirements are taken into account when formulating particular requirements for individual parts and steering elements. So, the requirements for the sensitivity of the car to steering and to the maximum effort on the steering wheel limit the steering gear ratio. To provide a "feeling of the road" and reduce the steering effort, the forward efficiency of the steering mechanism should be minimal, but from the point of view of the information content of the steering and its viscosity, the inverse efficiency should be high enough. In turn, high efficiency can be achieved by reducing frictional losses in the suspension and steering joints, as well as in the steering mechanism.

To ensure the minimum slip of the steered wheels, the steering linkage must have certain kinematic parameters.

Steering rigidity is of great importance for the car's handling. As the stiffness increases, the steering precision improves, and the steering response increases.

Steering friction plays both a positive and a negative role. Low friction worsens the rolling stability of the steered wheels, increases the level of their vibrations. Large friction reduces steering efficiency, increases steering effort, and impairs road feel.

Steering clearances also play both a positive and a negative role. On the one hand, if they are present, jamming of the steering control is excluded, friction is reduced due to the "shaking" of the nodes; on the other hand, the "transparency" of the steering control deteriorates, its speed deteriorates; excessive steering clearances can lead to self-oscillation of the steered wheels.

Special requirements are imposed on the geometric dimensions of the steering wheel and its design. An increase in the diameter of the steering wheel leads to a decrease in the effort on the steering wheel, however, it complicates its layout in the passenger compartment, worsens ergonomics and visibility. At present, the steering wheel diameter for small passenger cars of general purpose is 350 ... 400 mm.

The steering gear must provide a minimum clearance in the middle position of the steering wheel (corresponding to the straight-line movement of the car). In this position, the working surfaces of the parts of the steering mechanism are subject to the most intense wear, that is, the play of the steering wheel in the middle position increases faster than in the extreme ones. So that when adjusting the clearances there is no jamming in the extreme positions, the engagement of the steering mechanism is performed with an increased clearance in the extreme positions, which is achieved by constructive and technological measures. During operation, the difference in the meshing clearances in the middle and extreme positions decreases.

The steering gear should have a minimum number of adjustments.

To ensure the passive safety of the vehicle, the steering wheel shaft must bend or disengage in an accident; the steering column tube and its fasteners must not interfere with this process. These requirements are implemented in the automotive industry in the form of safety steering columns. The steering wheel must deform in an accident and absorb the energy transmitted to it. At the same time, it should not collapse, form fragments and sharp edges. Front wheel limiters on the swing arms or on the steering box should reduce stiffness even under heavy loads. This prevents kinking of the brake hoses, tire rubbing against the fender flaps and damage to suspension and steering components.

car steering gear rack

1.3 Analysis of known steering structures. Justification

selection of rack and pinion control

The steering wheel, through its shaft, transmits to the steering mechanism the torque developed by the driver and converts it into tensile forces on the one hand, and compression forces on the other, which, through the side rods, act on the pivot levers of the steering linkage. The latter are fixed on the pivot pins and rotate them to the required angle. The turning takes place around the pivot axles.

Steering gears are divided into rotary and reciprocating output mechanisms. Three types of steering mechanisms are installed on passenger cars: "worm-double-ridged roller", "screw-nut with circulating balls" - with a rotary movement at the output, and "gear-rack" - with rotational-translational.

The circulating ball screw-nut steering gear is quite sophisticated, but also the most expensive of all steering gears. In the screw pair of these mechanisms, there is not sliding friction, but rolling friction. The nut, being at the same time a rack, is in engagement with the toothed sector. Due to the small angle of rotation of the sector, it is easy for such a mechanism to realize a variable gear ratio with its increase as the angle of rotation of the rudder increases by setting the sector with eccentricity or by using a variable pitch of the gearing. High efficiency, reliability, stability of characteristics under heavy loads, high wear resistance, the possibility of obtaining a gap-free connection have led to the practical exclusive use of these mechanisms on cars of large and upper classes, partly in the middle class.

On passenger cars of small and very small classes, steering mechanisms of the "worm-roller" and "gear-rack" type are used. With the dependent suspension of the front wheels, which is currently used only on off-road and cross-country vehicles, a steering mechanism is required only with a rotary motion at the output. In terms of the overwhelming number of indicators, the mechanisms of the "worm-roller" type are inferior to the "gear-rack" mechanism and due to the convenience of the layout on front-wheel drive cars, the latter mechanisms are extremely widely used.

The advantages of rack-and-pinion steering are:

· Simplicity of construction;

· Low manufacturing costs;

· Ease of movement due to high efficiency;

· Automatic elimination of gaps between the rack and pinion, as well as uniform own damping;

· Possibility of hinged attachment of lateral transverse rods directly to the steering rack;

· Low pliability of steering and, as a consequence, its high speed;

· The small volume required to install this steering system (due to which it is installed on all front-wheel drive cars produced in Europe and Japan).

· Absence of a pendulum arm (including its supports) and medium thrust;

· High efficiency due to low friction both in the steering mechanism and in the steering gear by reducing the number of joints.

The disadvantages include:

· Increased sensitivity to shocks due to low friction, high return efficiency;

· Increased load from forces from the side rods;

· Increased sensitivity to steering fluctuations;

· Limited length of side rods (when they are hinged to the ends of the steering rack);

· Dependence of the angle of rotation of the wheels on the stroke of the gear rack;

· Increased efforts in the entire steering system due to sometimes too short pivoting levers of the steering linkage;

· Reduction of the gear ratio with an increase in the angle of rotation of the wheels, as a result of which maneuvering in the parking lot requires great efforts;

· The impossibility of using this steering in vehicles with dependent suspension of the front wheels.

The following types of rack and pinion steering are most widely used:

Type 1 - lateral arrangement of the gear (to the left or to the right, depending on the position of the steering wheel) when attaching the lateral rods to the ends of the toothed rack;

Type 2 - the middle arrangement of the gear with the same fastening of the steering rods;

Type 3 - lateral arrangement of the gear when attaching the lateral rods to the middle of the gear rack;

Type 4 - economical short version: lateral arrangement of the pinion by attaching both side rods to one end of the rack.

Type 1 rack and pinion steering is the simplest design and requires the least amount of space to accommodate it. Since the hinges of the side link attachments are fixed at the ends of the toothed rack. The rail is loaded mainly by axial forces. The radial forces, which depend on the angles between the side rods and the axis of the rack, are small.

In almost all front-wheel drive vehicles with a transverse engine arrangement, the steering linkage pivot levers are directed backward. If, in this case, due to a change in the height of the external and internal hinges of the side rods, the required inclination during cornering is not achieved, then, both during the compression stroke and during the rebound, the convergence becomes negative. Prevention of undesirable toe changes is possible in a car in which the steering gear is low and the side links are slightly longer than the lower wishbones. A more favorable case is the front position of the steering linkage, which is practically achievable only for cars of the classic layout. In this case, the pivoting levers of the steering linkage must be turned outward, the outer hinges of the side links go deep into the wheels, the side links can be made longer.

Rack and pinion steering type 2, in which the gear is mounted in the midplane of the vehicle, is used only on cars with a mid or rear engine location, since the middle engine location entails such a disadvantage as a large required volume for steering due to the need for "kink "steering shaft.

In the event that the steering gear must be positioned relatively high, it is inevitable that the side rods are attached to the middle of the rack when using a MacPherson suspension. A diagram illustrating the basics of choosing the length of the side rods for the MacPherson strut is shown in Fig. 1. In such cases, the inner joints of these rods are attached in the midplane of the vehicle directly to the rail or a member associated with it. In this case, the design of the steering mechanism should prevent the torsion of the gear rack by the moments acting on it. This imposes special requirements on the guide rails and drivers, since if the gaps are too small in them, the steering will be very difficult (due to high friction), if too large there will be knocks. If the cross-section of the toothed rack is not circular, but Y-shaped, then additional measures to prevent the rack from twisting around the longitudinal axis can be omitted.

Rice. 1. Determination of the length of the lateral link.

The type 4 steering system, which is installed on Volkswagen passenger cars, is easy to move and inexpensive to manufacture. The disadvantages include increased loads of individual parts and the resulting decrease in rigidity.

To prevent bending / twisting caused by the bending moment, the toothed rack has a relatively large diameter of 26 mm.

In practice, the choice of the type of rack and pinion steering is made from layout considerations. In our case, due to the lack of space for placing the steering mechanism at the bottom, the upper position of the steering mechanism is adopted. This necessitates the use of steering types 3.4. To ensure the strength and rigidity of the structure, the overhead steering arrangement and type 3 steering are finally adopted.

Admittedly, such a steering arrangement is not the most successful one. The high position of the steering gear makes it more flexible due to the deflection of the suspension struts. In this case, the outer wheel bends towards the positive camber, the inner wheel - towards the negative one. As a result, the wheels additionally tilt in the direction where the lateral forces tend to tilt them when cornering.

Kinematic calculation of the steering drive.

The kinematic calculation consists in determining the steering angles of the steered wheels, finding the gear ratios of the steering mechanism, drive and control as a whole, choosing the parameters of the steering linkage, as well as coordinating the steering and suspension kinematics.

1.4 Determining the parameters of the steering linkage

First, the maximum average steering angle required to move the vehicle with the minimum radius is calculated. According to the diagram shown in Fig. 2.

(1)

Rice. 2.Schema of turning a car with absolutely rigid wheels.

Rice. 3.Schema turning the car with flexible wheels.

In order for the steered rigid wheels to roll when cornering without slipping, their instantaneous center of rotation must lie at the intersection of the axes of rotation of all wheels. At the same time, the outer q n and inner q n angles of rotation of the wheels are related by the dependence:

(2)

where l 0 is the distance between the points of intersection of the axes of the pivots with the supporting surface. Since these points practically coincide for front-wheel-drive cars with the centers of contact of the wheels with the road (which is due to the small roll-in shoulder and the longitudinal angle of inclination of the king pin),

It is possible to provide such a dependence only with the help of a rather complex kinematic drive scheme, however, the steering linkage allows you to get as close to it as possible.

Due to the lateral pliability of the tires, the wheels roll with lateral forces under the influence of lateral forces. The turning diagram of a car with flexible wheels is shown in Fig. 3. For highly elastic tires, the shape of the trapezoid is brought closer to a rectangle in order to increase the efficiency of the outer, more loaded wheel. On some cars, the trapezoid is designed in such a way that the wheels remain approximately parallel up to a steering angle of »10 0. But at large angles of rotation of the wheels, the curve of the actual angles of rotation again reaches the curve of the required angles according to Ackermann. This reduces tire wear when parking and cornering.

The selection of trapezium parameters begins with determining the angle of inclination of the side trapezoid levers. Currently, this angle is usually chosen based on the design experience of previous models.

For the designed steering, we take l = 84.19 0.

Next, the length of the trapezium pivot arm is determined. This length is taken as large as possible according to the layout conditions. Increasing the length of the swing arm reduces the forces acting in the steering, as a result, increases the durability and reliability of the steering, as well as reduces its pliability.

In our case, the length of the pivot arm is taken equal to 135.5 mm.

Obviously, with an increase in the length of the pivot arm, the rack travel required to achieve a given maximum angle of rotation of the steered wheels increases.

The required rail travel is determined graphically or by calculation. Also, the kinematics of the steering linkage is determined graphically or by calculation.

Rice. 4. Dependence of the average angle of rotation of the steered wheels on the rack travel

In fig. 4 shows a graph of the dependence of the average angle of rotation of the wheels on the rack travel. The data for plotting was obtained using the WKFB5M1 program, which is used in the general layout department and the chassis department and the brakes department of the UPSh DTR VAZ to calculate the kinematics of the MacPherson suspension and rack and pinion steering. According to the graph, we determine that to ensure the angle of rotation of the wheels q = 34.32 0, the rail travel in one direction is equal to 75.5 mm. Full rail travel l = 151 mm.

In fig. 5 shows the dependence of the difference between the angles of rotation of the outer and inner wheels as a function of the angle of rotation of the inner wheel. It also shows the curve of the required change in the difference between the angles of rotation of the wheels, calculated according to Ackerman.

The indicator used to assess the kinematics of the steering drive is the difference in the angles of rotation of the wheels at the angle of rotation of the inner wheel equal to 20 0:

1.5 Steering gear ratio

The general kinematic steering gear ratio, determined by the gear ratios of the mechanism U r.m. and drive U r.p. is equal to the ratio of the total angle of rotation of the steering wheel to the angle of rotation of the wheels from lock to lock:

(5)

Rice. 5. Dependence of the difference between the angles of rotation of the wheels on the angle of rotation of the inner wheel:

1-calculated by the Ackermann ratio

2-for the designed car

For passenger cars with mechanical steering q r.k. max = 1080 0… 1440 0 (3… 4 turns of the steering wheel), in the presence of an amplifier q r.k. max = 720 0… 1080 0 (2… 3 turns of the steering wheel).

Usually, the number of revolutions of the steering wheel is determined within these limits based on the results of calculating the gear-rack gearing. In our case, the calculations showed the optimal number of revolutions equal to 3.6 (1296 0).

Then the total gear ratio is:

(6)

It is known that

(7)

Since a steering mechanism with a constant gear ratio is adopted for the designed car, U r.m. constant for any steering angle:

The steering gear ratio is not constant and decreases with increasing steering angle, which adversely affects the effort on the steering wheel when parking.

The dependence of the kinematic gear ratio of the designed steering is shown in Fig. 6

Rice. 6. Dependence of the steering gear ratio on the steering angle.

There are two approaches to matching suspension and steering kinematics. According to the first, during the rebound and compression strokes of the suspension, there should be no turning of the steered wheels; According to the second, more advanced one, the designer deliberately sets the law of changing the toe-in of the wheels during the suspension moves in order to improve the car's handling and reduce tire wear. According to the recommendations of the Porsche company, which are used at VAZ in the design, the toe-in of the wheels should increase during the rebound and decrease during the compression of the suspension. The rate of toe change should be 3-4 minutes per centimeter of suspension travel.

This work is carried out by the specialists of the general layout department and the synthesis of the suspension and steering kinematics is included, as a result of which the coordinates of the characteristic kinematic points are determined.

1.7 Calculation of the parameters of the gear-rack mechanism engagement

The calculation of the parameters of the gearing of the gear-rack transmission has a number of features. Since this transmission is low-speed and also backlash-free, special requirements for accuracy are imposed on the profile of the gear and rack teeth.

Initial data for calculations:

1. Module according to nomograms, usually from the standard series (1.75; 1.9; 2.0; ...) depending on the rack travel and the number of revolutions of the steering wheel: m 1 = 1.9

2. Number of gear teeth z 1. Also selected by nomograms. For rack and pinion steering mechanisms usually lies in the range of 6 ... 9. z 1 = 7

3. The angle of the original contour a and.sh. = 20 0

4. The angle of inclination of the pinion shaft axis to the longitudinal axis of the rack d = 0 0.

5. Gear tooth angle b.

The smallest slip and, consequently, the highest efficiency is provided at b = 0 0. in this case, axial loads do not act on the bearings of the pinion shaft.

Helical gearing is adopted when it is necessary to ensure increased strength, as well as for mechanisms with a variable gear ratio - to ensure smooth operation.

We accept b = 15 0 50 ".

6. Center-to-center distance a. It is usually taken as the minimum possible in terms of strength, which provides a compact design, reduces the weight of the steering mechanism and provides a good layout. a = 14.5 mm

7. Rod diameter d. To ensure the strength of the mechanism due to the length of the tooth, we take d = 26 mm.

8. The rail travel l p = 151 mm.

9. Coefficient of the radial clearance of the gear C 1 = 0.25 mm.

10. Ratio of the tooth head of the gear making tool

11. Coefficient of the radial clearance of the rail C 2 = 0.25 mm.

12. Ratio of the tooth head of the tool for making a rack

Calculation of gear parameters:

1. The coefficient of displacement of the original contour is minimal (determined from the condition of the maximum profile overlap)

2. The minimum diameter of the tooth stem.

3. Diameter of the main circle

(10)

4. Diameter of the starting circle

(11)

5. Ratio of the height of the tooth head

(12)

6. Angle of engagement (face angle) during manufacture

7. The maximum coefficient of displacement of the original contour x 1 max is determined from the condition that the thickness of the tooth head is equal to 0.4m 1. The calculation requires the diameter of the circumference of the tooth head d a 1. a preliminary calculation of the diameter of the tooth head is carried out according to the formula:

, (see Fig. 7.) (14)

The angle a SK is taken equal to 50 0, and then it is corrected by the operational method according to the formula:

(15)

where - correction to the angle a SK (rad);

(17)

Sufficient accuracy in calculating a SK is achieved after 4 operations

Then

(18)

8. Coefficient of displacement of the original contour x 1 is selected within x 1 min

9. Diameter of the circle of the gear tooth head d a 1 with the selected x 1:

d a 1 = 2m 1 (h * 01 + x 1) + d 01 = 19.87mm (19)

10.The diameter of the circumference of the tooth leg of the gear

11. The diameter of the active circle of the gear tooth foot d n 1 is calculated depending on the sign of B:

d n 1 = d B 1 for B £ Ф (21)

at B> Ф (22)

where (23);

h * a2 - ratio of the rack tooth head

d n 1 = 13,155 mm

Gear Tooth Height

(24)

12. Angle a SK with the accepted coefficient of displacement of the original contour x 1:

(25)

13. The proportional overlap in the end section e a is calculated depending on A:

(27) at A<Ф

where A = a-r Na 2 -0.5d B 1 cosa wt is the distance between the active line of the rack tooth head and the main circle;

r Na 2 - distance from the staff axis to the active line of the tooth head

14. Axial overlap in the end section

(28)

where b 2 is the average width of the rack tooth

15. End module

(29)

16. Gear radial clearance

C 1 = m n C 1 * = 0.475 mm (30)

17. Basic step

P b = pm n cosa 01 = 5.609 mm (31)

18. Coefficient of displacement of the original contour in the end section

x f1 = x n1 × cosb 1 = 0.981 (32)

19. Thickness of the tooth on the base circle in the end section

S bt1 = (2 х 1 tga 0 + 0.5p) cosa wt m t + d B1 × inva wt = 4.488210mm (33)

inv a wt = tga wt –a wt / 180 = 0.01659 (34)

20. Thickness of the gear tooth head

Pinion diameter at the end of the rack

for d a 1 -d y> 0 for d a 1 -d y £ Ф d a 1 = d y

where r Na 2 is the distance from the rod axis to the active line of the tooth head

21. Measured number of gear teeth

(37)

rounded down, where b B = arcsin (cosa 0 × sinb 01) is the angle of inclination of the tooth along the main circle;

P l = pm n cosa 01 - main step

22. Length of the common normal

W = (z "-1) P b + S bt1 cosb B = 9.95mm (38)

23. Minimum active gear width

1.8 Calculation of the rail parameters

1. The angle of inclination of the tooth of the rack

b 02 = d-b 01 = -15 0 50 "(40)

2. Ratio tooth head ratio

h * a2 = h * ap01 -C * 2 = 1.25 (41)

3. Radial clearance of the rack

C 2 = m n C * 2 = 0.475 (42)

4. Distance from the axis of the rack to the centerline of the tooth

r 2 = a-0.5d 01 -m n x 1 = 5.65 mm (43)

5. Distance from the axis of the staff to the line of the tooth stem

r f2 = r 2 -m n h * ap02 = 4.09 mm (44)

6. Distance from the staff axis to the active line of the tooth head

r Na2 = r 2 + m n h * ap01 -m n C * 2 = 8.025mm (45)

7. Distance from the axis of the rack to the line of the tooth head of the rack

r a 2 = r Na 2 + 0.1 = 8.125 (46)

8. Average width of the rack teeth

9. Distance from the axis of the staff to the active line of the root of the tooth

r N2 = a-0.5d a1 cos (a SK -a wt) = 5.78 mm (48)

10. Height of the rack tooth head

h a2 = r a2 -r 2 = 2.475 mm (49)

11. Height of the leg of the rack tooth

h f2 = r 2 -r f2 = 1.558mm (50)

12. Height of the rack tooth

h 2 = h a 2 - h f 2 = 4.033 mm (51)

13. End step

(52)

14. Thickness of the tooth of the rack at the foot

S fn2 = 2 (r 2 - r f2) tga 0 + 0.5pm n = 4.119 mm (53)

15. Width of the hollow at the leg

S ef2 = pm n - S fn2 = 1.85 mm (54)

16. Thickness of the rack tooth head

S an2 = 0.5 pm n - (r Na2 + 0.1- r 2) 2tga 0 = 1.183 mm (55)

17. Radius of the base of the leg of the tooth of the rack

P f2 = 0.5 S ef2 × tan (45 0 + 0.5d 0) = 1.32 mm (56)

18. Minimum number of rack teeth z 2 min:

where l p is the rail travel

Loss of length (difference between total engagement and rack travel) (58);

(59)

l 1 = a-r a2 (60)

(62)

(63)

19. Diameter of the measuring roller theoretical

round up to the existing d 1 = 4.5 mm

20. Measured dimension from the edge of the rail

21. Measured diameter from the rail axis

22. Measured diameter to the tooth head

23. Measured diameter to the root of the tooth

Chassis parameters depend on the type of body, the location of the engine and gearbox, the mass distribution of the vehicle and its external dimensions. In turn, the steering scheme and design depend both on the parameters of the vehicle as a whole and on the decisions made on the scheme and design of other chassis and drive elements. The steering layout and design are determined early in the vehicle design phase.

The basis for the choice of the control method and the layout of the steering circuit are the characteristics and design solutions adopted at the stage of preliminary design: maximum speed, base size, wheel formula, axle load distribution, minimum turning radius of the vehicle, etc.

The steering of a VAZ-2110 car consists of a rack-and-pinion steering mechanism and a steering drive. The design presented in the graphic part of this diploma project is a rack and pinion steering gear with rods assembled, as well as working drawings of its parts.

Rack and pinion steering mechanisms are more common, since they have a low weight, high efficiency and increased rigidity, they are well combined with hydraulic amplifiers, which led to their use on passenger cars with a front engine, for example, on the VAZ-2110, steering is used due to the fact that that this car model has a maximum steering axle load of up to 24 kN.

The steering diagram of a VAZ-2110 car is shown in Fig. 8. In this figure:

1 - thrust tip head;

2 - ball joint;

3 - swivel levers;

5 - tubular rod;

6 - horizontal rods;

8 - fastening rod;

12 - connecting plate;

13 - lock plate;

14 - rubber-metal hinge;

15 - sealing rings;

16 - bushing;

17 - rail;

18 - crankcase;

19 - clamp;

20 - elastic coupling;

21 - steering rods;

22 - damping element;

23 - steering wheel;

24 - deep groove ball bearing;

26 - steering column;

27 - bracket;

28 - protective cap;

29 - roller bearing;

30 - drive gear;

31 - ball bearing;

32 - retaining ring;

33 - protective washer;

34 - sealing rings;

35 - nut;

36 - anther;

37 - rubber ring;

38 - retaining ring;

39 - cermet stop;

40 - spring;

44 - nut.

Figure 9 shows a rack and pinion steering gear assembly.

This design includes:

1 - protective cap;

2 - steering gear housing;

3 - steering rack;

4 - drive gear;

5 - steering rod;

6 - spacer sleeve that limits the rail travel;

7 - bolt of fastening of the steering rod, tighten with moments of 7.8 ± 0.8 kgf × m and lock them by bending the edges of the locking plate on the verge of the bolts;

8 - connecting plate;

9 - persistent sleeve;

10 - support of the steering mechanism, tightly fitting to the cover;

11 - support sleeve of the rail;

12 - protective cover, installed so that its right end is at a distance of 28.5 -0.5 mm from the end of the pipe, and secured with clamps;

13 - clamp;

14 - thrust ring of the rack, which limits the rack travel;

15 - a sealing ring of the rail stop;

16 - nut;

17 - rail stop;

18 - roller bearing;

19 - ball bearing;

The set screw is loaded with a radial force F r = 985 H and F L 1 = 1817.6 H.

Thread M32 x 1.5

Material:

Grub screw GD - Z and Al 4

Bushing CDAl 98 Cu 3

Carrying thread length 5 mm.

Contact voltage

Material for all force-transmitting parts, such as steering link arms, swing arms, transverse links, ball joints, etc., must have a sufficiently large elongation. When overloaded, these parts should deform plastically, but not collapse. Parts made of materials with low elongation, such as cast iron or aluminum, must be correspondingly thicker. When the steering is locked, when any of its parts is destroyed or loosened, the car becomes uncontrollable, and an accident is almost inevitable. This is why the reliability of all parts is important.

6. Ilarionov V.A., Morin N.M., Sergeev N.M. Theory and design of the car. Moscow: Mechanical Engineering, 1972

7. Loginov M.I. Car steering. Moscow: Mechanical Engineering, 1972

8. Lukin P.P., Gaparyants G.A., Rodionov V.F. Car design and calculation. Moscow: Mechanical Engineering, 1984

9. Labor protection in mechanical engineering. M.: mechanical engineering, 1983

10. Labor protection at road transport enterprises. Moscow: Transport, 1985

11. Raimpel J. Car chassis. Moscow: Mechanical Engineering, 1987

12. Tchaikovsky I.P., Solomatin P.A. Steering controls of cars. M. Mechanical Engineering, 1987

INTRODUCTION

The discipline "Fundamentals of calculating the structure and units of cars" is a continuation of the discipline "Construction of cars and tractors" and the purpose of the course work is to consolidate the knowledge gained by the student in the study of these disciplines.

Course work is carried out by the student independently using textbooks, teaching aids, reference books, GOSTs, OSTs and other materials (monographs, scientific journals and reports, the Internet).

Course work includes the calculation of vehicle control systems: steering (odd number of student's code) or brake (even number of student's code). The prototype of the car and the initial data are selected according to the last two digits of the student's code. Coefficient of adhesion of wheels to the road = 0.9.

For steering, the graphic should be: 1) a diagram of the car's turning with an indication of the radius and angles of the steered wheels, 2) a diagram of the steering linkage with the calculated formulas of its parameters, 3) a diagram of the steering linkage in determining the dependence of the angles of rotation of the outer and inner steered wheels in a graphical way , 4) graphs of the dependences of the angles of rotation of the outer and inner steered wheels, 5) the general scheme of steering, 6) the scheme for calculating the stresses in the steering bipod.

The graphic part on the brake system should contain: 1) a diagram of the brake mechanism with the calculated formulas of the braking torque, 2) the static characteristic of the brake mechanism, 3) a general diagram of the brake system, 4) a diagram of a brake valve or a master brake cylinder with a hydraulic vacuum booster.

Initial data for traction, dynamic and economic calculation of the vehicle.

Car steering calculation

Main technical parameters

Minimum turning radius (outside wheel).

where L is the base of the car;

Нmax is the maximum angle of rotation of the external steering wheel.

At a given value of the minimum radius and base of the car, the maximum angle of rotation of the outer wheel is determined.

In accordance with the vehicle turning pattern (which must be drawn up), determine the maximum angle of rotation of the inner wheel

where M is the distance between the axes of the pivots.

Geometric parameters of the steering linkage.

To determine the geometric parameters of the steering linkage, graphical methods are used (it is necessary to draw up a diagram to scale).

The length of the transverse link and the sides of the trapezoid is determined based on the following considerations.

The intersection of the extension of the axes of the side levers of the trapezoid is at a distance of 0.7L from the front axle, if the trapezoid is rear, and at a distance L, if the trapezoid is front (determined by the prototype).

The optimal ratio of the length m of the lateral trapezoid arm to the length n of the transverse link is m = (0.12 ... 0.16) n.

The numerical values of m and n can be found from the similarity of triangles

where is the distance from the king pin to the point of intersection of the extension of the axes of the lateral levers of the steering linkage.

Based on the data obtained, the graphical construction of the steering trapezoid is carried out on a scale. Then, having plotted the position of the journal of the inner wheel at equal angular intervals, the corresponding positions of the outer wheel are graphically found and a graph of the dependence is plotted, which is called the actual. Further, according to equation (2.5.2), a theoretical dependence is constructed. If the maximum difference between the theoretical and actual values does not exceed 1.50 at the maximum angle of rotation of the inner wheel, then the trapezoid is considered to be correctly selected.

The steering angle ratio is the ratio of the elementary steering angle to the half-sum of the elementary steering angles of the outer and inner wheels. It is variable and depends on the gear ratios of the steering gear Uрм and the steering gear U рп

The steering gear ratio is the ratio of the elementary angle of rotation of the steering wheel to the elementary angle of rotation of the bipod shaft. The maximum value should correspond to the neutral position of the steering wheel for passenger cars and the extreme position of the steering wheel for trucks without power steering.

The steering gear ratio is the ratio of the arms of the drive levers. Since the position of the levers in the process of turning the steering wheel changes, the steering gear ratio is variable: Uрп = 0.85 ... 2.0.

Power steering ratio

where is the moment applied to the steering wheel;

The moment of resistance to turning the steered wheels.

When designing cars, both the minimum (60N) and the maximum (120N) force are limited.

According to GOST 21398-75, for turning in place on a concrete surface, the force should not exceed 400 N for cars, 700 N for trucks.

The moment of resistance to turning the steered wheels is calculated using the empirical formula:

where is the coefficient of adhesion when turning the wheel in place (= 0.9 ... 1.0);

Рш - air pressure in the tire, MPa.

Steering wheel parameters.

The maximum angle of rotation of the steering wheel in each direction is within 540 ... 10800 (1.5 ... 3 turns).

The diameter of the steering wheel is standardized: for light-duty cars and trucks it is 380 ... 425 mm, and for trucks 440 ... 550 mm.

Effort on the steering wheel for turning in place

Rr.k = Mc / (), (1.8)

where Rpk is the steering wheel radius;

Steering efficiency.

Steering efficiency. Direct efficiency - when transferring power from the steering wheel to the bipod

рм = 1 - (Мтр1 / Мр.к) (1.9)

where Мтр1 is the friction moment of the steering mechanism, reduced to the steering wheel.

Reverse efficiency characterizes the transfer of force from the bipod to the steering wheel:

pm = 1 - (Mtr2 / Mv.s) (1.10)

where Мтр2 - the moment of friction of the steering mechanism, reduced to the bipod shaft;

Mv.s is the moment on the bipod shaft, supplied from the steered wheels.

Efficiency, both direct and reverse, depend on the design of the steering mechanism and have the following meanings:

pm = 0.6 ... 0.95; pm = 0.55 ... 0.85

Vehicle control mechanisms- these are mechanisms that are designed to ensure the movement of the car in the desired direction, and its deceleration or stop, if necessary. Control mechanisms include the vehicle's steering and braking system.

Steering car- this isa set of mechanisms that serve to turn the steered wheels, provides car movementin a given direction. The transmission of the steering wheel turning effort to the steered wheels is provided by the steering drive. To facilitate driving, power steering is used. , which make turning the steering wheel easy and comfortable.

1 - transverse thrust; 2 - lower arm; 3 - pivot pin; 4 - upper arm; 5 - longitudinal thrust; 6 - steering gear bipod; 7 - steering gear; 8 - steering shaft; 9 - steering wheel.

Steering principle

Each steering wheel is mounted on a steering knuckle connected to the front axle by means of a king pin, which is fixedly attached to the front axle. When the driver rotates the steering wheel, the force is transmitted by means of rods and levers to the steering knuckles, which rotate at a certain angle (set by the driver), changing the direction of the vehicle.

Control mechanisms, device

The steering consists of the following mechanisms:

1. Steering gear - a deceleration gear that converts steering wheel shaft rotation to bipod shaft rotation. This mechanism increases the force applied to the steering wheel the driver and facilitates his work.
2. Steering drive - a system of rods and levers, which, in conjunction with the steering mechanism, turns the car.
3. Power steering (not on all vehicles) - It is used to reduce the effort required to turn the steering wheel.

1 - Steering wheel; 2 - shaft bearing housing; 3 - bearing; 4 - steering wheel shaft; 5 - steering propeller shaft; 6 - steering linkage thrust; 7 - tip; 8 - washer; 9 - hinge pin; 10 - cross-piece of the cardan shaft; 11 - sliding fork; 12 - the tip of the cylinder; 13 - sealing ring; 14 - tip nut; 15 - cylinder; 16 - piston with rod; 17 - sealing ring; 18 - support ring; 19 - cuff; 20 - pressure ring; 21 - nut; 22 - protective sleeve; 23 - steering linkage thrust; 24 - oiler; 25 - rod tip; 26 - retaining ring; 27 - plug; 28 - spring; 29 - spring holder; 30 - sealing ring; 31 - upper insert; 32 - ball finger; 33 - bottom insert; 34 - pad; 35 - protective sleeve; 36 - steering knuckle lever; 37 - steering knuckle body.

Steering drive device:

1 - spool body; 2 - sealing ring; 3 - the ring of plungers is movable; 4 - cuff; 5 - steering gear housing; 6 - sector; 7 - filler plug; 8 - worm; 9 - side crankcase cover; 10 - cover; 11 - drain plug; 12 - spacer sleeve; 13 - needle bearing; 14 - steering bipod; 15 - thrust bipod steering; 16 - steering gear shaft; 17 - spool; 18 - spring; 19 - plunger; 20 - valve body cover.

Oil tank.1 - Tank body; 2 - filter; 3 - filter housing; 4 - bypass valve; 5 - cover; 6 - breather; 7 - filler neck plug; 8 - ring; 9 - suction hose.

Booster pump. 1 - pump cover; 2 - stator; 3 - rotor; 4 - body; 5 - needle bearing; 6 - spacer; 7 - pulley; 8 - roller; 9 - collector; 10 - distribution disk.

Schematic diagram. 1 - high pressure pipelines; 2 - steering mechanism; 3 - pump of the amplifying mechanism; 4 - drain hose; 5 - oil tank; 6 - suction hose; 7 - delivery hose; 8 - amplifying mechanism; 9 - hoses.

Steering of the KamAZ car

1 - valve body for hydraulic booster control; 2 - radiator; 3 - cardan shaft; 4 - steering column; 5 - low pressure pipeline; 6 - high pressure pipeline; 7- hydraulic reservoir; 8- power steering pump; 9 - bipod; 10 - longitudinal thrust; 11 - steering gear with hydraulic booster; 12 - bevel gear housing.

The steering mechanism of the KamAZ car:

1 - reactive plunger; 2- control valve body; 3 - driving gear wheel; 4 - driven gear wheel; 5, 22 and 29 - retaining rings; 6 - bushing; 7 and 31 - persistent stakes to ", 8 - sealing ring; 9 and 15 - bandages; 10 - bypass valve; 11 and 28 - covers; 12 - crankcase; 13 - piston rack; 14 - cork; 16 and 20 - nuts; 17 - gutter; 18 - ball; 19 - sector; 21 - lock washer; 23 - case; 24 - thrust bearing; 25 - plunger; 26 - spool; 27- adjusting screw; 30- adjusting washer; 32-toothed sector of the bipod shaft.

Steering control of the ZIL car;

1 - power steering pump; 2 - pump reservoir; 3 - low pressure hose; 4 - high pressure hose; 5 column; 6 - signal contact device; 7 - turn signal switch; 8 cardan joint; 9 - cardan shaft; 10 - steering gear; 11 - bipod.

Steering of the MAZ-5335 car:

1 - longitudinal steering rod; 2- power steering; 3 - bipod; 4 - steering gear; 5- cardan joint of the steering drive; 6 - steering shaft; 7- steering wheel; 8 - transverse tie rod; 9- left control rod arm; 10 - pivot arm.

Design and calculation of the steering drive. Dynamic calculation Calculation of car steering gas

Send your good work in the knowledge base is simple. Use the form below

Similar documents

Introduction

Thread M32 x 1.5

INTRODUCTION

Car steering calculation

Main technical parameters

Steering principle

Control mechanisms, device

The steering consists of the following mechanisms:

Steering drive device:

Send your good work in the knowledge base is simple. Use the form below

Similar documents

Introduction

Thread M32 x 1.5

INTRODUCTION

Car steering calculation

Main technical parameters

Steering principle

Control mechanisms, device

The steering consists of the following mechanisms:

Steering drive device:

Read also