JPH04198837A - Diagnostic apparatus for braking performance of vehicle - Google Patents

Abstract

PURPOSE:To diagnose braking capacity while an actual running scene is set by providing from and rear as well as left and right friction roller pairs having regions high and low in the coefficient of friction on the outer peripheral surfaces thereof and rotating in synchronous relation to the rotatory powers of wheels. CONSTITUTION:Front and rear wheels are placed and fixed on vehicle rollers 2, 6, 8 to be diagnosed, for example, so that left front and rear wheels are placed on the regions 3, 3a high in frictional resistance of the rollers 2, 6 and right front and rear wheels are placed on the regions low in frictional resistance of the rollers 2, 6. When a vehicle reaches diagnosing speed, a vehicle receiving stand 14 is raised to a place where all of the wt. of the vehicle is not applied to the rollers 2, 6 by a lift apparatus 12 to push up the vehicle. Thereafter, the vehicle is braked. At the time of the start of braking and after the start of braking, the frictional resistance with a road surface becomes different between the left and right wheels. By this method, it can be diagnosed whether ABS braking performance is correctly developed in a diagnostic apparatus main body corresponding to an actual road surface state by taking out signal from a detector.

Description

[Detailed Description of the Invention] "Industrial Application Field" The present invention relates to a braking performance diagnostic device for a vehicle, and in particular to a so-called anti-skid brake control mechanism (hereinafter referred to as "anti-skid brake control mechanism") that performs optimal braking to match vehicle speed and wheel speed as much as possible. , rABS
Say J. ) concerning a braking performance diagnostic device for Western military vehicles.

``Prior Art'' Conventionally, one embodiment of this type of vehicle braking performance diagnostic apparatus is disclosed in, for example, Japanese Patent Laid-Open No. 1-148649.

However, the braking performance measuring device disclosed in this publication is
A pair of rotating wheels arranged in parallel are positioned on the frame so as to correspond to the tire mounting positions, and a drive motor is attached to one of the rotating wheels, and the vehicle side tires are rotated by the driving force of this drive motor. is placed perpendicularly to the rotating wheel,
The braking operation status of the vehicle controlled by the anti-skid brake control mechanism is appropriately measured by the measuring device itself.

Therefore, this braking performance measuring device basically starts the braking operation while maintaining the driving rotation of the rotating wheel on the measuring device main body side.

However, this braking performance measuring device had the following drawbacks.

■ In actual driving, a vehicle is always subject to load resistance from the road surface, and when brake brake operation is started, not all four wheels are subject to frictional resistance from the road surface under the same conditions. However, since conventional measuring devices do not take into account differences in frictional resistance, they cannot measure or diagnose whether ABS is actually working properly for all four wheels.

■ Since this is a so-called pseudo measurement method in which the brake brake operation is basically started while the drive rotation of the rotating wheels is maintained, it is difficult to measure when driving on real roads with complex friction surfaces.
It is difficult to determine whether the ABS is working correctly.

■ To diagnose ABS, it is necessary to rotate the wheels at a certain high speed using a high-horsepower motor or the like to rotate the tires. Therefore, a large capacity power source is required.

■ In relation to the above ■, high speed driving (around 100K/H)
Diagnosis of ABS is difficult or impossible.

``Problems to be Solved by the Invention'' In view of the above-mentioned drawbacks of the conventional technology, the present invention aims to diagnose whether or not ABS is actually operating for each wheel while setting a realistic driving situation as much as possible. In addition, it does not require a large-capacity power supply, and it is easy to diagnose ABS when driving at high speeds (around 100 K/H). Furthermore, even when sudden braking is applied, the force applied to the vehicle fixing device can be reduced. To provide a vehicle braking performance diagnostic device capable of sufficiently diagnosing ABS and also capable of lifting the vehicle by a desired amount.

``Means for Solving the Problems'' The vehicle braking performance diagnostic device of the present invention has a portion with a high friction coefficient and a portion with a low friction coefficient on the outer peripheral surface, and synchronously based on the rotational force of the wheel. A pair of rotating friction rollers on the front, rear, left and right sides, a lift device installed in a pit formed on the floor or on the floor to push up or lift the wheels so that they do not separate from the friction rollers, and The present invention is characterized in that it includes vehicle fixing devices that are respectively disposed in front and rear of the vehicle to be diagnosed and fix the vehicle to be diagnosed.

In the above configuration, the vehicle braking performance diagnostic device includes a plurality of detectors that detect the rotation speed of the sensor rotor attached to the axle of each wheel of the tested vehicle, and signals from these detectors. The present invention is characterized in that a signal distributor that receives signals and sends signals to the ABS control unit and the main body of the diagnostic apparatus is installed at appropriate locations around the vehicle to be diagnosed.

Furthermore, the above-mentioned lift device that pushes up the vehicle so that the wheels do not separate from the friction rollers has a load meter on the top surface of the vehicle cradle, and this load meter is electrically connected to the main body of the above-mentioned diagnostic device. Features.

``Example'' The present invention will be described in detail below using examples shown in the drawings.

In one embodiment from FIG. 1 to FIG. 5, 1 is the floor surface F.
A friction roller and a lift device, which will be described later, are provided in this pit 1. That is, 2 is a pair of left and right front friction rollers having a region 3 with a high coefficient of friction and a region 4 with a low coefficient of friction on their outer peripheral surfaces, and the left and right sides of these front friction rollers 2.2 are connected via a free joint 5. There is.

Reference numeral 6 designates a pair of left and right rear friction rollers having a portion 3a with a high friction coefficient and a portion 4a with a low friction coefficient on the outer peripheral surface. The left and right sides of these rear friction rollers 6.6 are also connected via free joints 7.

Therefore, the portion 3.3a with a high coefficient of friction and the portion 4.4a with a low coefficient of friction are provided so as to be symmetrical with respect to the direction of approach of the vehicle V to be diagnosed. In this embodiment, as shown in FIGS. 1 and 3, the regions 3.3a of the front and rear friction rollers with high coefficients of friction are located on the outside, while the regions 4.4a with low coefficients of friction are located on the inside. They are located respectively. Here, a region with a high coefficient of friction means a large number of grooved surfaces to increase the coefficient of friction, and a region with a low coefficient of friction here means a smooth surface to reduce the coefficient of friction.

8 is provided behind the rear friction roller 6, and
The third roller rotates in the same direction as the rear friction roller 6 by the rear wheel.
The left and right sides of these third rollers 8.8 are also connected via a free joint 9.

As shown in FIG. 1, each of these rollers 2.6.8 is rotatably mounted on a frame 10 provided in the pit 1 at a required interval, and is connected to the front friction roller 2. The rear friction roller 6 includes a belt wheel 11a, a belt llb
They are provided so as to be synchronously interlocked with each other by power transmission means 11 such as the following.

Next, reference numeral 12 denotes a lift device installed in the pit 1 in this embodiment so as to be located between the front friction roller 2 and the rear friction roller 6. It has left and right vehicle supports 14.14 that push up the diagnostic vehicle V so that it does not move away from the friction rollers 2.6.

Reference numeral 15 designates a plurality of vehicle fixing devices, four in this embodiment, which are arranged on the left and right sides of the front and rear of the vehicle to be diagnosed in order to fix the vehicle to be diagnosed riding on the friction roller 2.6. . These vehicle fixing devices 15 are fixed pillars 1 fixedly erected on the floor surface F, respectively, as shown in FIG.
6, and a connecting belt or rope 17, one end of which is attached to the support column 16, and the other end of which is appropriately attached to the vehicle to be diagnosed.

Next, sensor rotors a 1 and b 1 18 are installed at appropriate locations on or around the vehicle to be diagnosed, and are also attached to the axles of the wheels aSbSc and d of the vehicle to be diagnosed, respectively. , C1, and dl.

Next, 19 is a signal distributor that receives the signals from the detector 18 and sends the signals to the ABS control unit 20 on the vehicle side and the diagnostic device main body 21 that diagnoses the braking performance of the vehicle. This signal distributor 19 is installed and entered at an appropriate location around the vehicle to be diagnosed (2).

Therefore, the diagnostic device main body 21 is a central processing unit CPU.
and via the input/output interface 22,
A display device 23, a recorder 24, etc. are connected.

Note that 25 controls each brake cylinder 26a, 26 based on a control signal from the ABS control unit 20 side.
Actuators 527a, 27b, 27c perform operations such as removing the hydraulic pressure applied to b126c, 26d.

27d is the caliper, 128 is the master cylinder, 29
is the brake pedal.

"Function" In the above configuration, first the vehicle to be diagnosed (■) is moved to each roller 2.
6.8 and secure it with the vehicle fixing device 15. In this case, the left and right wheels (tires) of the vehicle V to be diagnosed are, for example, as shown in FIG. - Place the rear wheels S and d so that they are on the right side, at the area 4.4a where the coefficient of friction is low. -Next, start the engine of the vehicle to be diagnosed (■) and rotate the wheels (tires) until it reaches a certain high speed range. Each roller 2.6 due to rotation of wheels (tires)
．． 8 rotates synchronously.

Next, when the running speed of the vehicle to be diagnosed (2) reaches the diagnostic speed, the lift device 12 is driven to lift the vehicle to the desired position so that all of the weight of the vehicle (2) to be diagnosed does not rest on the friction rollers 2.6. Raise the platform 14 and push up the vehicle to be diagnosed (■). After that, brakes are applied to the vehicle to be diagnosed.

Therefore, at the start of the braking operation and after the start of the braking operation, the left wheels a and c and the right wheels S and d have different frictional resistances on the road surface. Therefore, in this way, signals are extracted from each detector 18 to determine whether or not the braking performance of the ABS is operating properly in response to the actual road surface condition, and the diagnosis device main body 21 diagnoses the signal via the signal distributor 19. Ru. To diagnose the operating state of ABS, place one wheel on the area 3.3a (outside) with a high friction coefficient, then slightly shift the position of the vehicle V to be diagnosed, and place the wheel on the - side with a high friction coefficient. It is carried out on the lower part 4.4a of the body.

In the embodiment of the present invention, the lift device 2 does not necessarily have to be installed in the pit 1, but can be installed at an appropriate location on the floor F. In this case, the vehicle to be diagnosed (2) is lifted up by a support arm.

Next, other embodiments shown in FIGS. 6 and 7 will be described. It should be noted that since this embodiment includes the main parts of the present invention as is, the same parts are given the same reference numerals and redundant explanations will be omitted.

This embodiment is mainly different from the embodiments of the present invention described above. It is electrically connected to the diagnostic device main body 21A via the input/output interface 22A.

With this configuration, it is possible to set the load reduction of the vehicle V to be diagnosed at a constant reference value or target value, and to perform accurate diagnosis based on this target value.

"Effects of the Invention J As is clear from the above explanation, the present invention has the following effects.

(1) Since we use a pair of front, rear, left, and right friction rollers that have areas with a high friction coefficient and areas with a low friction coefficient on their outer peripheral surfaces, check whether the ABS of the vehicle being diagnosed is actually operating for each wheel. Please try to diagnose while setting up a realistic driving situation as much as possible.

(2) The pair of front, rear, left and right friction rollers rotates synchronously based on the rotational force of the wheels of the vehicle to be diagnosed, allowing for high-speed operation.
For example, testing at around 100K/)1 can be easily performed. Furthermore, since a drive motor is not used to rotate the friction roller, a large-capacity power source is not required for high-speed operation.

(3) Since a lift device is used to push up or lift the vehicle to be diagnosed so as not to separate from the friction rollers, it is possible to easily obtain a slip condition of the vehicle (tires). In particular, when a vehicle is lifted up using a lift device, the ground load of the friction rollers is less than the inertial weight of the vehicle, so the time from when the brakes are applied until the friction rollers come to a stop becomes even slightly longer.

Therefore, the braking performance of ABS can be sufficiently confirmed or diagnosed.

(4) Furthermore, when a lift device is used, the ground load on the friction roller is reduced, so even when the brake is applied, the force applied to the vehicle fixing device is reduced.

Therefore, it is possible to brake suddenly without causing damage to the vehicle.

(5) In the case of an embodiment in which a load meter is installed on the vehicle cradle of the lift device to detect the weight of the vehicle to be diagnosed, the diagnosis can be performed while measuring the ground load on the friction roller of the vehicle to be diagnosed. .

BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1 to 5 are explanatory views showing one embodiment of the present invention, and FIGS. 6 and 7 are explanatory views showing other embodiments of the present invention. 2... Front friction roller, 3.3a... Portion with high friction coefficient, 4.4a... Portion with low friction coefficient, 6... Rear friction roller, 8... Third port~u, IO
...Frame, 11...Power transmission means 12
．． 12A...Lift device, 14.14A...Vehicle cradle, 15...Vehicle fixing device, 18...Detector, 19...Signal distributor, 2L 21A...Diagnostic device main body, 30 ···load cell. Patent applicant Nissan Motor Sales Co., Ltd. Patent applicant Nissan Motor Co., Ltd.

Claims (1)

[Scope of Claims] 1) A pair of front, rear, left and right friction rollers which have a region with a high friction coefficient and a region with a low friction coefficient on their outer circumferential surface and rotate synchronously based on the rotational force of the wheels, and a floor surface. Lift devices are provided in a pit formed in a pit or on a floor surface to push up or lift the wheels so that they do not separate from the friction rollers, and lift devices are provided in front and rear of the vehicle to be diagnosed riding on the friction rollers, respectively. A braking performance diagnostic device for a vehicle, comprising: a vehicle fixing device for fixing a vehicle to be diagnosed; 2) A pair of front, rear, left and right friction rollers that have a region with a high friction coefficient and a region with a low friction coefficient on the outer peripheral surface and rotate synchronously based on the rotational force of the wheels, and a pit formed on the floor surface. Alternatively, a lift device is provided on the floor and pushes up or lifts the wheels so that they do not separate from the friction rollers, and a lift device is provided respectively in front and rear of the vehicle to be diagnosed riding on the friction rollers to fix the vehicle to be diagnosed. A vehicle fixing device that detects the number of revolutions of sensor rotors that are respectively attached to the axle of each wheel of the vehicle to be diagnosed, and receives signals from these detectors;
A braking performance diagnostic device for a vehicle, comprising a signal distributor that sends signals to a BS control unit and a diagnostic device main body. 3) A pair of front, rear, left and right friction rollers that have a region with a high friction coefficient and a region with a low friction coefficient on the outer peripheral surface and rotate synchronously based on the rotational force of the wheels, and a pit formed on the floor surface. a lift device for pushing up the wheels so that they do not separate from the friction rollers, a load meter for detecting the weight of the lift device installed on the top surface of a vehicle holder of the lift device, and a vehicle to be diagnosed riding on the friction rollers. A vehicle fixing device that is disposed in front and rear of the vehicle to fix the vehicle to be diagnosed, and a plurality of detectors that detect the rotation speed of the sensor rotor that is respectively attached to the axle of each wheel of the vehicle to be diagnosed;
Receive signals from these detectors, and
A braking performance diagnostic device for a vehicle, comprising a signal distributor that sends signals to a BS control unit and a diagnostic device main body electrically connected to the load meter.