RU-2861476-C1 - SUSPENSION FOR REAR AXLE OF VEHICLE WITH LOAD-BEARING BODY

RU2861476C1RU 2861476 C1RU2861476 C1RU 2861476C1RU-2861476-C1

Abstract

FIELD: mechanical engineering. SUBSTANCE: suspension for a rear axle of a vehicle with a load-bearing body comprises a rear axle with a beam and two lower longitudinal rods connected to the rear axle beam. A shock absorber and a spring and an upper triangular arm are mounted on the axle beam. The arm has a central part and a pair of spaced apart end parts. A ball joint is connected to the central part of the arm. The joint is configured to interact with a mounting plate mounted on the axle beam. Each of the shock absorbers is combined into one unit with the corresponding spring. The mounting plate is made in the form of a bracket rigidly fixed on the rear part of the rear axle beam, and is provided with a sleeve for the threaded part of the ball pin of the ball joint. The spherical part of the ball pin is movably mounted in the ball joint housing. The joint housing is fixed in the central part of the triangular upper arm. The stability, controllability and safety of vehicle movement are improved, the kinematic characteristics of the suspension and the ride smoothness are improved. EFFECT: increasing the stability and safety of vehicle movement, improving the kinematic characteristics of the suspension. 4 cl, 8 dwg

Inventors

BABURIN ALEKSANDR VIKTOROVICH
Shcherbak Evgenii Nikolaevich
Abliasov Vitalii Leonidovich

Dates

Publication Date: 20260505
Application Date: 20251208

Claims (4)

1. A suspension for the rear axle of a vehicle with a monocoque body, comprising a rear axle with a beam, two lower longitudinal rods connected to the rear axle beam, a shock absorber and a spring mounted on the axle beam, and an upper arm of a triangular shape, having a central portion and a pair of spaced end portions, with the central portion of which a ball joint is connected, configured to interact with a mounting plate mounted on the axle beam, characterized in that each of the shock absorbers is combined into a single unit with a corresponding spring; the mounting plate is made in the form of a bracket rigidly fixed to the rear portion of the rear axle beam, and is provided with a bushing for a threaded portion of the ball pin of the ball joint; the spherical portion of the ball pin is movably mounted in the housing of the ball joint, fixed in the central portion of the upper arm of a triangular shape.
2. A rear axle suspension according to paragraph 1, characterized in that the geometric center of the ball joint is located in the longitudinal plane of the vehicle, behind the rear axle beam at a distance of 50 to 150 mm from the axis of rotation of the rear wheels and in the range of -50 to +100 mm relative to the upper overall point of the rear axle beam.
3. A suspension for the rear axle according to paragraph 1, characterized in that a pair of spaced end parts of the upper arm of a triangular shape, extending from its central part, goes around the rear axle gearbox.
4. A suspension for the rear axle according to paragraph 1, characterized in that it is equipped with a stabilizer, the longitudinal arms of which are connected to the end spaced parts of the upper arm of a triangular shape.

Description

Field of technology. The invention relates to the field of mechanical engineering, namely automotive engineering, and concerns the design of the rear suspension of vehicles, primarily all-wheel drive vehicles. Prior art. The rear suspension of the VAZ-2121 automobile and its subsequent modifications (produced since 1977) is known and is described in detail in the technical literature, for example, see “VAZ-2121 NIVA Automobile”, V.A. Vershigora, A.P. Ignatov, K.B. Pyatkov, Moscow, Transport, 1980. See p. 145, Fig. 119. Rear suspension. This suspension is classified in the automotive industry as a dependent suspension with a rod guide vane. Specifically, it consists of a drive axle beam, including the welded axle beam itself, a gearbox flanged to the beam, and axle shafts with hubs and brakes. Coil springs rest on the beam near the wheel via welded cups, with compression buffers located within the springs on an extension bracket. The guide vane consists of two lower and two upper control arms, which transmit longitudinal forces and moments during acceleration and braking through welded brackets. Lateral forces are transmitted by a Panhard rod located behind the axle, the left side of which is attached to the axle beam bracket, and the right side to the body bracket. The shock absorbers are mounted behind the axle and angled toward the center of the vehicle, allowing them to accommodate the necessary suspension travel. This suspension remains in production without significant modifications to this day. This type of suspension has a number of design disadvantages compared to independent and semi-independent suspensions (the rear suspension is on "interconnected" control arms, as in most front-wheel drive vehicles). This is primarily due to its guide vane. As is well known, a Panhard rod guide vane, although the simplest technical solution for transmitting lateral forces, nevertheless has the disadvantage of causing undesirable lateral displacement of the rear axle during suspension travel (see "CAR CHASSIS. Suspension Designs" by J. Reimpel, Translated from German by V.P. Agapov // Moscow, Mashinostroenie, 1989, p. 155, Fig. 3.10.). This is caused by the fact that the Panhard rod describes the radius of a circle around the attachment point on the body. Deviation of the Panhard rod length from the theoretical axis of the axle, located in the central plane of the car, leads to lateral displacement of the rear axle. When the car is moving at high speed, this displacement necessitates correction of the car's trajectory and reduces overall driving stability. This property of the Panhard rod is enhanced if the rod is positioned at an inclined position in the suspension. It should also be noted that the inclined position of the Panhard rod (which occurs whenever the car is only occupied by the driver or is partially loaded) creates reactions on the body during a right turn, resulting in an increase in body roll (see "CAR CHASSIS. Suspension Designs" by J. Reimpel, Translated from German by V.P. Agapov // Moscow, Mashinostroenie, 1989, p. 155, Fig. 3.12). As a result, both when the car is moving in a straight line on an uneven surface and when turning corners, the driver experiences discomfort and is forced to reduce speed or adapt to the car's reaction in order to maintain control over the car. Due to the fact that in recent years the quality of the road network and maximum speeds on them have significantly improved, as well as the trend towards increasing engine power, the requirement for the safety and stability of vehicles at high speeds has sharply increased. This, for all-wheel drive vehicles with a monocoque body, such as, for example, the VAZ-2121 and its modifications, has made the requirement for improving the kinematic characteristics of the rear suspension the most important and relevant. There are various technical solutions to correct this deficiency. For example, on the Mazda RX-7 (see "CAR CHASSIS. Suspension Designs" by J. Reimpel, Translated from German by V.P. Agapov // Moscow, Mashinostroenie, 1989, p. 158, Fig. 3.17.), equipped with a rotary piston engine and developing a speed of over 200 km/h, and having the same rod-type rear dependent suspension, a Watt mechanism is used instead of a Panhard rod to transmit lateral forces. The Watt mechanism is used as an improvement on the method of transmitting lateral forces through a Panhard rod. Both methods are designed to prevent the vehicle axle from shifting laterally relative to its (vehicle) body (or chassis), while allowing the axle to move in the vertical direction. The Watt mechanism provides movement closer to a straight line than a Panhard rod. For layout reasons, the Watt linkage axle is mounted offset from the vehicle's centerline on the cast rear axle differential housing. This bracket placement reduces the strength requirements for the welded beam. Therefore, the axle beam does not require reinforcement in the Watt linkage mounting area. Fu