RU2545531C1 - Upgraded test bench by osipov for diagnostics of vehicle brake - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: test bench comprises two supports movable in longitudinal direction and having horizontal contact surface to install the wheels of an axis being tested, a separate drive of movable supports by steel ropes wound onto traction drums, the drums are set on one drive shaft rotating in adjusting bearings by a motor and a variator, ball guides to move the movable supports in longitudinal direction. The test bench also comprises a device signalling the start of the movable supports' travelling, a device to determine the force at a brake pedal and its automatic drive, polymer coating, weight sensors, sensors of travelling start and of force at every support, sensors of wheel angular velocities, the signals from the latter sensors are sent to a computer for processing via an amplifier and an analogue-to-digital converter, a drum with steel rope to return the supports into the initial working position, a platform on which the ball guides of one of the movable supports are set, the platform can move in cross direction by sliding guideways by means of a drive screw gear, and rolling supports for all-wheel drive vehicles.

EFFECT: improved quality of braking parameters measurement to get reliable diagnosis of technical state of the brakes.

2 dwg

Description

The invention relates to the field of mechanical engineering, namely to diagnose brakes of motor vehicles.

The claimed invention relates to a priority area of development of science and technology "Technology to reduce risk and reduce the consequences of natural and technological disasters" [Alphabetical subject index to the International Patent Classification in priority areas of science and technology / Yu.G. Smirnov, E.V. Skidanova, S.A. Krasnov. - M .: PATENT, 2008. - p.65]

Known platform inertial brake stand (Technical operation of cars: Textbook for high schools / Edited by G.V. Kramarenko. - 2nd ed., Revised and additional - M .: Transport, 1983. P.148, Fig. 6.35 . [1]) with movable platform supports for installing the wheels of a diagnosed vehicle.

Signs of an analogue that coincide with the essential features of the claimed device are: longitudinally movable supports for mounting the wheels of the diagnosed vehicle, horizontal arrangement of the supports, wheel contact with the same surface and bearing surface in bench and road conditions.

The disadvantages of this stand include the large footprint required to accelerate the vehicle, the increased geometric dimensions of the platforms, the dependence of the diagnostic results on the accuracy of the vehicle’s arrival on the platforms, the dependence of the effort and speed of pressing the brake pedal on the driver’s qualifications, the need for repeated control rides on the platform of the stand . This does not allow to achieve the accuracy of measuring the braking parameters, to avoid a large variation in the values of the measured parameters and to obtain reliable results of the diagnosis of brakes.

Known brake stand with movable sections on which are located roller bearings for the wheels of the axle under test driven by an electric motor (patent 2316438, RU, IPC 7 B60T 17/22, G01L 5/28. Device for diagnosing a brake system of a vehicle. Application 2006115873 from 10.05 .2006. Registered on February 10, 2008. Published on February 10, 2008. Bull. No. 4. [2]).

Signs of an analogue that coincide with the essential features of the claimed device are: movable bearings for mounting the wheels of the axle under test, drive supports from an electric motor, the availability of instruments and devices for measuring braking parameters.

The disadvantages of this stand include: high energy costs, the complexity of the suspension of the movable sections, the instability of the coefficient of adhesion of the wheels, uneven in area and shape of the contact of the wheel with cylindrical roller bearings and the horizontal plane of the road in bench and road conditions.

Known test bench with support rollers and flywheels, the drive of which is possible from the diagnosed vehicle (patent 2276026 C1, RU, IPC B60T 17/22, G01L 5/28. Test bench. Application 2004130234/11 from 2004.10.12. Published 2006.05.10. [3]).

Signs of an analogue that coincide with the essential features of the claimed device are: adjustable distance between the supports for installing the wheels of the vehicle, the availability of instruments and devices for measuring braking parameters.

The disadvantages of this stand are: increased time for diagnosing brakes, instability of the coefficient of adhesion of the wheels, unequal in size and shape of the contact of the wheel with cylindrical roller bearings and the horizontal plane of the road in bench and road conditions, the gas contamination of the room with exhaust gases. In addition, the diagnosis at this stand is associated with the cost of expensive liquid fuel.

A well-known stand for diagnosing brakes of motor vehicles (patent 2323841 C1, RU, IPC B60T 17/22, G01L 5/28. A stand for diagnosing brakes of motor vehicles. Application 2006124360/11 of 2006.07.06. Published 2008.05.10 [4]).

Signs of an analogue that coincide with the essential features of the claimed device are: movable supports for installing wheels of a vehicle, the presence of frames and guides for moving supports.

The disadvantages of this stand are: diagnostics of brakes in static with non-rotating wheels locked, impossibility of quantitative assessment of diagnostic braking parameters in dynamics due to the lack of appropriate measuring devices, impossibility of quantitative assessment of vehicle stability during braking, high metal consumption due to the presence of upper and lower frames, their guides, hinges, axles, etc., a large mass of movable supports (tables) with concrete coating, st stationary character of the location due to the binding power equipment to the pit, the capital cost for installation due to the need to prepare for a special booth with the foundation pit.

The closest technical solution adopted as a prototype is the Osipov test bench for diagnosing vehicle brakes (patent 2391237 C1, RU, IPC 7 B60T 17/22, G01L 5/28, G01M 17/007. Application 2008139838/11 of 07.10. 2008. Registered on June 10, 2010. Published on June 10, 2010. Bull. No. 16 [5]).

Common features of the prototype with the claimed stand are: two movable in the longitudinal direction of the support with a horizontal contact surface for installing the wheels of the tested axis; separate drive of movable supports that do not have a rigid connection with each other; ball guides for moving the movable bearings in the longitudinal direction; a device signaling the beginning of the movement of movable supports; a device for determining the force on the brake pedal and its automatic drive; a polymer coating with an adhesion coefficient of at least 0.8 on the horizontal contact surfaces of the movable supports; sensors of weight, the beginning of movement and force on each movable support, the signals from which are fed through an amplifier and an analog-to-digital converter to a computer that outputs the results of the diagnosis of the brakes of each wheel to a printing device and a monitor screen; the existing guest diagnosis technique or the author’s method, taking into account the coefficient of non-uniformity of the increase in braking torque K _NMM , the coefficient of unevenness of the axle wheel blocking in time K _NB and the unfolding moment M _DEVELOPMENT. characterizing the stability of the vehicle.

The disadvantages of the prototype are:

- unregulated distance between the movable bearings, not allowing the wheels of vehicles with different tracks to be installed on the longitudinal axis of symmetry of the supports and to exclude the formation of the unfolding moments of the forces on the supports;

- drive movable bearings from the power cylinders, not providing synchronous movement of these supports when diagnosing brakes;

- the return of the movable bearings to their original position due to tensile springs, changing their length during operation in the direction of increase;

- errors in the measurement of braking parameters associated with the aforementioned structural disadvantages of the prototype, in particular the immobility of the supports in the transverse direction and the imperfect drive of the movable bearings in the longitudinal direction;

- lack of wheel speed sensors;

- lack of devices necessary for diagnosing all-wheel drive brakes of motor vehicles.

The claimed invention is aimed at solving the problem of: setting movable bearings along a track of wheels of a motor vehicle to eliminate on these supports when braking the wheels of torsional moments of forces; providing synchronous movement of movable supports with the same linear speed; stable return of movable supports to their original working position; providing the ability to measure the angular velocity of rotation of the wheels; providing the opportunity to diagnose all-wheel drive vehicles and, ultimately, improving the quality of measuring braking parameters to obtain a reliable diagnosis of the technical condition of the brakes.

In accordance with the task, the technical result of the invention is: setting the movable bearings along the track of the wheels of the tested axis and excluding the appearance of unfolding forces on these bearings, synchronous movement of the movable bearings with the same linear speed, stable return of the movable bearings to their original working position, measurement of angular rotational speeds wheels, diagnosing four-wheel drive vehicles by equipping the stand with the necessary technical devices, which together and allows to improve the quality of measurement of braking parameters to obtain a reliable diagnosis of the technical condition of the brakes.

The technical result of the invention is achieved by the fact that in the patented stand for diagnosing brakes of a motor vehicle, containing two longitudinally movable bearings with a horizontal contact surface for mounting wheels of the axle under test, separate drive of movable bearings that do not have a rigid connection with each other, ball guides for moving movable supports in the longitudinal direction, a device that signals the beginning of the movement of movable supports, a device for determining the force on the brake pedal and its automatic drive, a polymer coating with an adhesion coefficient of at least 0.8 on the horizontal contact surfaces of the movable supports, weight sensors, the beginning of movement and force on each movable support, the signals from which are fed to the computer through an amplifier and an analog-to-digital converter issuing the results of diagnosing the brakes of each wheel to a printing device and a monitor screen, the existing guest method of diagnosis or the author’s method, taking into account the unequal coefficient ernosti increase braking torque K _HHM, irregularity coefficient block the wheels of one axis with respect to time _{of NB} To a yawing moment M and _developed. , which characterizes the stability of vehicles under braking, according to the invention, the platform on which the ball guides are located for moving in the longitudinal direction of one of the movable supports is mounted on the transverse sliding guides and can be moved along with the movable support in the transverse direction by exposing the movable bearings bearings along the track of the wheels of the axle under test; movable bearings are driven by two steel ropes wound around two identical the dimensions of the traction drum located on one drive shaft connected via a variator to an electric motor or any other principle of operation, the traction drums rotate freely on the drive shaft and move along its axis with the possibility of rigid fixation in the required place by means of coupled controlled couplings, movably mounted on splines drive shaft, the return of the movable bearings to their original working position is carried out by one steel rope wound around a central drum mounted similar to immediately on the drive shaft between the traction drums, the stand contains sensors of angular speeds of rotation of the wheels, the stand comes with roller bearings for installing untestable wheels of four-wheel drive vehicles and devices for fixing the latter when diagnosing brakes.

The difference from the prototype is:

- a platform that is movable in the transverse direction due to the helical gear transmission and transverse sliding guides, on which the ball guides of one of the movable bearings are located, which makes it possible to set the movable bearings along the track of the wheels of the axle under test and to avoid the occurrence of torque moments on the movable bearings;

- the drive of the movable bearings by two steel ropes wound around the same size drums, which allows for synchronous movement of the movable bearings in the longitudinal direction and to minimize the measurement error of the braking parameters;

- the return of the movable supports to their original working position with one steel rope wound around the central drum, which allows stably returning the supports to their original working position;

- sensors of angular speeds of rotation of the wheels;

- devices to diagnose all-wheel drive vehicles, in particular roller bearings for installing untestable wheels and devices for fixing the vehicle on a stand.

The presence of a new set of essential distinctive features from the prototype in the inventive stand for diagnosing brakes of a vehicle allows us to conclude that the claimed invention meets the criterion of "novelty."

An additional comparative analysis of patent and scientific and technical information did not reveal sources containing information about the popularity of the set of distinctive features of the claimed stand for diagnosing vehicle brakes, which indicates its compliance with the criterion of "inventive step".

The invention is illustrated by drawings:

Figure 1 - Schematic diagram of the inventive stand.

Figure 2 is a diagram of the drive of movable supports for installing wheels of the tested axis of the vehicle.

In figure 1 and figure 2 adopted the following conventions:

1 - movable support for installing wheels;

2 - traction drum of a movable support;

3 - an electric motor or other principle of action;

4 - variator, changing the speed of the traction drum;

5 - ball guide for the longitudinal movement of the supports;

6 - light signaling device;

7 - a device for driving the brake pedal and determining the force;

8 - emphasis for wheels of non-wheel drive vehicles;

9 - sensor weight load on the wheel;

10 - sensor of the beginning of movement of the movable support;

11 - force sensor (braking force);

12 - amplifier signals from all sensors;

13 - analog-to-digital Converter of the incoming signals;

14 - computer;

15 - printing device;

16 - monitor;

17 - roller bearing for wheels of four-wheel drive vehicles;

18 - wheel speed sensor;

19 - movable in the transverse direction of the platform;

20 - sliding guide of the movable platform;

21 - running helical gear of the movable platform;

22 - steel rope drive movable bearings;

23 - a drive shaft of drums;

24 - the installation bearing of the drive shaft;

25 - coupled controlled coupling;

26 - steel rope returning supports to their original working position;

27 - drum return movable supports to their original working position;

28 - leveler steel ropes;

29 is a block guiding the steel rope.

The stand contains two unrelated movable bearings 1 for mounting the wheels of the tested axis of the vehicle. Each support is driven by a steel rope 22, wound on an independent traction drum 2, freely mounted on the drive shaft 23. The drive shaft 23 is rotated in the mounting bearings 24 by the engine 3 through the variator 4 with the required speed and required force. By means of the coupled controlled couplings 25, the traction drums 2 are rigidly fixed on the drive shaft 23 so that the fastening of the steel ropes 22 to the traction drums 2 is on a continuation of the axis of symmetry of the movable bearings 1. When the traction drums 2 are rotated together with the drive shaft 23, the steel ropes 22 are evenly wound on the drums and move along the ball guides 5 movable bearings 1 in the longitudinal direction towards the wheels of the vehicle. The return of each movable support 1 to its original working position is carried out by one steel rope 26, wound on the central return drum 27 using equalizer 28 and two independent blocks 29. A device 6 is installed in a place visible from the vehicle’s cab signaling the beginning of movement of the movable supports. The stand is equipped with a device 7 for determining the force on the brake pedal and its automatic drive (pedameter), angular velocity sensors of the tested wheels 18, two stops 8, which exclude the vehicle from rolling back when diagnosing, roller bearings 17 for installing untestable wheels of four-wheel drive vehicles and devices for fixing the latter on the stand. A weight sensor 9, a start-up sensor 10, and a force sensor 11 are installed on each movable support 1. The signals from all of the above sensors and measuring devices are fed to a computer measuring system containing a signal amplifier 12, an analog-to-digital converter 13, a computer 14, a printing device 15 and monitor 16. To move one of the movable supports in the transverse direction when exhibiting these supports along the track of the wheels of the axle under test, the stand contains a movable platform 19 that is transversely moved in the transverse direction the original sliding guide 20 by means of a helical gear transmission 21 together with a support movable in the longitudinal direction.

Diagnosis of vehicle brakes at the claimed stand is carried out according to the author’s method, which differs from known diagnostic methods in that when diagnosing the effectiveness of brakes and vehicle stability during braking, along with the parameters regulated by GOST R 51709-2001 (GOST R 51709-2001 Motor vehicles. Safety requirements for the technical condition and inspection methods. - Instead of GOST 25478-91; introduced 2002-01-01 - M .: Gosstandart of Russia: Publishing house of standards, 2001. - 44 p. [6]): an effort organ management _RP, specific braking force Y _T, the relative difference in brake forces F, as well as the operating time of brake _{τ CP = (τ C + τ} H) ( during road tests) used new highly estimation parameters: uneven growth inhibitory factor moment _KNM , characterizing the difference in the intensity of growth of the braking torque on the wheels of one axle, the coefficient of uneven blocking of the wheels of one axle in time K _NB and the unfolding moment M _DEVELOPMENT. , characterizing the stability of the vehicle during braking.

The numerical value of the coefficient K _NNM is determined from the expression

, $${\stackrel{•}{М}}_{Т\text{ ПР}}$$

- темп нарастания тормозного момента на левом, правом колесе соответственно.Where $${\stackrel{•}{M}}_{TLE\mathrm{AT}}$$

, $${\stackrel{•}{M}}_{T\text{ETC}}$$

- the rate of increase of braking torque on the left, right wheel, respectively.

The unevenness coefficient of blocking the axle wheels in time K _NB is defined as

where t _{B K LEFT} , t _{B K PR} - the blocking time of the left, right wheel of one axis.

_Turning Point M _DEVELOPMENT. determined by the formula

where R _X - the values of the longitudinal reactions of the wheels;

B _A - car track.

According to the author’s method, the diagnosis of brakes at the claimed stand is carried out in the following sequence.

1. By means of a helical gear drive 21, moving the platform 19 in the transverse direction along the sliding guides 20, the movable bearings 1 of the stand are set along the track of the wheels of the axle under test;

2. Traction drums 2 are set on the drive shaft 23 so that the fastening of the steel ropes 22 to the drums is on the continuation of the axis of symmetry of the respective movable bearings 1, after which the drums are rigidly fixed in this position by means of coupled controlled couplings 25;

3. The vehicle enters the wheels of the axle under test on the movable supports of 1 stand, while the wheels are mounted on the longitudinal axis of symmetry of these supports;

4. The vehicle is fixed from moving in the longitudinal direction back with the help of two stops 8, mounted under the wheels of the non-tested axle;

5. A device 7 is installed on the brake pedal to determine the force and automatically drive the pedal;

6. The variator 4 in the drive shaft system 23 sets the traction force corresponding to the rated braking force of the diagnosed vehicle;

7. The exhaust pipe of the vehicle, when diagnosing the latter in an enclosed space, is connected to the exhaust gas exhaust system, and the engine is started to bring the brake system to working condition;

8. Automatically or by a diagnostician (operator), the engine 3 and the traction drums 2, rigidly connected to the drive shaft 23, are manually put into operation, they begin to wind the steel ropes 22;

9. Under the influence of the traction forces of the steel ropes 22, the movable bearings 1 are moved on ball guides 5 in the longitudinal direction towards the motor vehicle, bringing its wheels into rotation;

10. When moving the movable bearings 1, the sensors located on them start to move 10, and the device 6 is turned on, signaling the beginning of the movement of the movable supports;

11. At the signal of the device 6, automatically by means of the device 7 for determining the force on the brake pedal and its automatic drive, or directly by the driver, the rotating wheels of the tested axis are braked;

12. In the process of braking the wheels of the axle under test, signals from the device 7 located on the brake pedal, weight sensors 9, sensors for starting movement 10, force sensors 11 located on the movable bearings 1, and angular velocity sensors of the tested wheels are amplified by the signal amplifier 12, an analog-to-digital converter 13 onwards for processing to a computer 14.

13. When the rotating wheels of the axle under test (blocking) stop, the engine 3 is turned off, the drive shaft 23 with the traction drums 2 stops rotating, the movable bearings 1 stop and the vehicle moves off the stand.

14. By means of the coupled controlled couplings 25, the traction drums 2 are disconnected from the drive shaft 23 and the central return drum 27 is rigidly connected to this shaft by the coupled controlled coupling 25.

15. The engine 3 is turned on and a steel rope 26 is wound on the central return drum 27, which, using the equalizer 28 and blocks 29, returns the movable bearings 1 to their original operating position.

16. A motor vehicle enters the wheels of the non-tested axis onto the movable bearings of stand 1, and operations are repeated until the brakes of the wheels of all axles are checked.

When diagnosing four-wheel drive vehicles, the wheels of the non-tested axis (s) are mounted on the roller bearings 17 included in the package of the stand, and the vehicle is fixed with additional devices.

After processing the received signals, the computer 14 provides the diagnostic results in quantitative digital terms to the printing device 15 and in graphical terms in the form of brake diagrams of the left and right wheels on the monitor 16.

The above-described claimed stand allows you to reliably diagnose the brakes of vehicles with a different base and number of axles, as well as any wheel formula in conditions as close as possible to the real road braking conditions, both according to the existing guest, and according to the proposed author’s method.

Claims (1)

A stand for diagnosing motor vehicle brakes, comprising two longitudinally movable bearings with a horizontal contact surface for mounting the wheels of the axle under test, a separate drive of the movable bearings, ball guides for moving the movable bearings in the longitudinal direction, a device that signals the start of movement of the movable bearings, a device for determining the force on the brake pedal and its automatic drive, a polymer coating with an adhesion coefficient of at least 0.8 on horizontal contact surfaces of movable supports, weight sensors, the beginning of movement and force on each support, characterized in that the platform on which the ball guides of one of the movable supports are located is mounted on sliding guides with the possibility of moving in the transverse direction by means of a helical gear for setting the movable support along the track of the wheels of the tested axis, the movable bearings are connected by means of steel ropes and traction drums through a variator with an electric motor or other principle The traction drums are freely mounted on one drive shaft and are equipped with coupled controlled couplings located on the splines of the drive shaft for rigid connection with it; movable bearings for returning to the initial position are connected by a steel cable to the central drum, similarly mounted on one drive shaft between the drive shaft drums, the stand includes wheel speed sensors, roller bearings for installing wheels of four-wheel drive vehicles and locking devices driving movements in the diagnosis of brakes.

Images