JPH05185921A - Brake system for multi-shaft trailer - Google Patents

Abstract

PURPOSE:To simplify the constitution as the brake system for a trailer, and apply an appropriate braking power to the respective wheels in the antiskid control. CONSTITUTION:When all the pressures applied to brake chambers 51R, 51L, 52R, 52L for the respective wheels 41R, 41L, 42R, 42L on the different axles 41, 42 are commonly controlled, proportional pressure reducing control valves 80R, 80L are interposed between the brake chambers 51R 51L while are provided for the wheels 41R, 41L among a plurality of wheels where the braking load becomes small and the antiskid control valve devices 61R, 61L.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a brake system having an anti-skid control function,
The present invention relates to a braking technique that can be effectively used for a multi-axle trailer having a plurality of axles in the front-rear direction of a vehicle body.

[0002]

2. Description of the Related Art Generally, in order to simplify the overall structure of a brake system, it is known to use the same parts or devices included in the system (for example, Japanese Patent Laid-Open No. Sho 60-60). 185662). Applying this idea to a multi-axle trailer, a sensor that detects the rotational state of only one wheel among multiple wheels (on multiple axles) is installed, and a discrimination circuit is based on the signal from that sensor. It is conceivable that the pressures of all brake actuators (followers) of a plurality of wheels are commonly controlled by the anti-skid control valve device.

In such a case, the system configuration certainly becomes simple. However, in the case of a multi-axle trailer, the axle weight changes during braking for a plurality of axles in the front-rear direction of the vehicle body. Therefore, if the same braking force is applied to each wheel on the axle, proper anti-skid control cannot be performed. In particular, the problem with the multi-axle trailer becomes significant because the combination with the tractor that pulls the multi-axle trailer differs from time to time and each tractor itself has different suspension characteristics. For example, in a 2-axle semi-trailer, if you install the wheel speed sensor only on the front axle side,
Insufficient braking force is applied to the wheels of the rear axle, and if the wheel speed sensor is mounted only on the rear axle side, the braking force of the wheels of the front axle becomes excessive, resulting in locking.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a technique capable of exerting an appropriate braking force on each wheel during anti-skid control while simplifying the structure as a brake system for a trailer as much as possible. To do.

[0005]

According to the present invention, when the pressures of all brake actuators (followers) for different wheels on different axles are controlled in common, a wheel having a lighter load during braking is selected from a plurality of wheels. A proportional pressure-reducing control valve is interposed between the follower provided as an anti-skid control valve device. As the proportional pressure reducing control valve, a known limiting quick release valve, load sensing valve or the like can be used as the valve itself. In this way, common control of multiple followers simplifies the system, while providing a proportional pressure reducing control valve for a particular follower prevents associated wheel lock and Sufficient braking force can be applied to the wheels on the axle.

[0006]

[First Embodiment] FIG. 1 shows a basic configuration of a brake system when the present invention is applied to a two-shaft semi-trailer. In FIG. 1, a portion 10 surrounded by a chain double-dashed line is a vehicle body of a semitrailer. This vehicle body is provided with three couplers 11S, 11E and 12 for connecting to the tractor side (not shown). Two couplers 11S and 11E
Is a hose coupler, and one coupler 11S is for the service line 13 and the other coupler 11E is for the emergency line 15. The remaining coupler 12 is an electrical coupler and is connected to the electronic control unit 20 via the cord 16. The service line 13 and the emergency line 15 are connected to the corresponding ports of the relay emergency valve 25. The relay emergency valve 25 first functions as a relay valve. When the signal pressure from the brake valve on the tractor side is applied to the valve 25 via the service line 13, the valve 25 supplies the air in the air reservoir 26 to the brake line 30 according to the signal pressure. Further, the relay emergency valve 25 functions to apply an emergency brake to the semi-trailer side when the coupler 11E is removed or the emergency line 15 is damaged.

The semi-trailer 10 includes a front shaft 41 and a rear shaft 4.
2 and 2 axles, and each axle has a pair of left and right wheels (or wheel groups) 41L, 41R; 42L, 42R. Then, for each wheel 41L, 41R; 42L, 42R,
Brake chambers 51L, 51R, which are followers; 52
L and 52R are provided. It goes without saying that each of these brake chambers 51L, 51R; 52L, 52R is supplied with brake pressure from the relay emergency valve 25 side via the brake line 30. The brake system belonging to the brake line 30 has two independent right and left.
It is a channel. The brake line 30 is a common line 30C extending from the relay emergency valve 25.
And two branch lines 30R and 30L branched from it
Consists of. The anti-skid control valve devices 61R and 61L and the brake chambers 51L and 51R; 52L and 52R are provided on the respective branch lines 30R and 30L. Each anti-skid control valve device 61R, 61L,
Consisting of a known solenoid valve device including a shutoff valve and a slack valve,
Based on a command from the electronic control unit 20 that constitutes the determination circuit, each brake chamber 51L, 51R; 52
The brake pressure of the branch lines 30R and 30L leading to L and 52R is controlled. In order to control the brake pressure in this way, it is necessary to monitor the rotation state of the left and right wheels. It uses a wheel speed sensor, but one for each left and right channel to simplify the system.
Two sensors 71R and 71L are provided. The first embodiment shown in FIG. 1 is front shaft sensing, and sensors 71 are provided for the left and right wheels 41R and 41L on the front shaft 41, respectively.
R and 71L are provided

In the semi-trailer 10, the front axle 41 and the rear axle 42 have different axial loads or axial loads during braking, and the front axle 41 is lighter than the rear axle 42. Therefore, the proportional pressure reducing control valves 80R and 80L are provided between the brake chambers 51R and 51L for braking the wheels 41R and 41L on the front shaft 41 and the left and right anti-skid control valve devices 61R and 61L, respectively. ing. As the proportional pressure reducing control valves 80R and 80L, known valves can be used. For example, Japanese Patent Laid-Open No.
Limiting quick release valve as disclosed in Japanese Patent No. 148650, or actual opening 1-1308
A load sensing valve or the like as disclosed in Japanese Patent No. 65 may be used. Such proportional pressure reducing control valves 80R, 8
0L reduces the pressure of the branch lines 30R and 30L at a predetermined ratio, and reduces the reduced brake pressure to the brake chamber 51.
R, add to 51L. Therefore, it is possible to optimize the brake pressure applied to the wheels 41R and 41L on the front shaft 41 by setting the brake pressure that has been reduced to the extent that the axle load is lightened during braking. Also,
To the wheels 42R, 42L on the rear shaft 42, it is possible to supply an appropriate brake pressure so that the brake pressure does not become insufficient while considering the pressure reducing ratios of the proportional pressure reducing control valves 80R, 80L.

[0009]

[Second Embodiment] FIG. 2 shows another example when applied to a two-shaft semi-trailer. Also in this example, the basic part of the brake system is the same as that of the first embodiment of FIG. Therefore, corresponding similar parts are designated by the same reference numerals, and description thereof will be omitted. Here, the description will focus on the parts that are different from the first embodiment. The first embodiment is front-axis sensing, and uses sensors 71R,
In that the 71L is provided on the axle side where locking easily occurs,
It can be said that this is an example of mainly preventing lock. On the other hand, the second embodiment is rear axle sensing, in which the sensors 71R and 71L are provided for the wheels 42R and 42L on the rear axle 42.
Since it is the same semi-trailer, it is the front shaft 41 side that the axial load is lightened during braking. However, since the proportional pressure reducing control valves 80R and 80L are provided for the brake chambers 51R and 51L related to the front shaft 41 side as well, the antiskid control function by the antiskid control valve devices 61R and 61L is provided. In addition, the pressure reducing function of the proportional pressure reducing control valve can reliably prevent the lock. Therefore, in the second embodiment, as the rear axle sensing, the rear axle 4 is likely to suffer from insufficient braking force.
A sufficient braking force is applied to the wheels 42R and 42L on the second side.

In each of the embodiments shown in FIGS. 1 and 2, the left and right are independently applied to two channels, but the left and right can be commonly used in the form of one channel. In addition to the 2-axis semi-trailer,
It can also be applied to a three-axis or four-axis full trailer.
For example, when applied to a three-axis type, it is possible to provide proportional pressure reducing control valves having different pressure reducing ratios for the other two axes except for the last one, which has the largest axle weight during braking. Alternatively, the proportional pressure reducing control valve may be provided only for the center shaft, and
A common proportional pressure reducing control valve may be provided for the shafts, and a proportional pressure reducing control valve having a different pressure reducing ratio for the front one shaft (having a larger pressure reducing ratio than that for the rear two shafts) may be provided. it can. In the case of a three-axle vehicle, in order to prevent the wheel lock more reliably, a wheel speed sensor is provided for each of the front one-axle wheel and the rear two-axle wheel, for example, the last axle wheel. Can be worn. Even in that case, since the sensor for the wheel of the middle axle is not attached, the system can be simplified accordingly.

When the proportional pressure-reducing control valve 80R (or 80L) is provided in the brake system, it may be provided in the middle of the piping, or part of the piping may be omitted, so that it is necessary to connect the piping. It can also be provided so as to be integrated with an adjacent device. FIG. 3 shows a third embodiment in which the proportional pressure reducing control valve 80R is integrated with the anti-skid control valve device 61R.

[0012]

[Third Embodiment] The anti-skid control valve device 61R is
For example, as disclosed in Japanese Patent Application Laid-Open No. 62-253554, its internal structure is well known, so a detailed description thereof will be omitted here. The anti-skid control valve device 61R is provided with two solenoid valve mechanisms of a holding valve and an exhaust valve (both not shown) in the housing 600, and is switched into three modes of boosting (filling), holding, and depressurizing (relaxing). Replace. The switching is performed by the electronic control unit 20, and the connector 610 for electrical connection with the unit 20 is located on the side portion of the housing 600. The housing 600 includes a relay emergency valve 25.
In addition to the inlet 620 connected to the side, the outlet 630 connected to the proportional pressure reducing control valve 80R side, the exhaust port 64 communicating to the atmosphere
There is 0. On the other hand, the limiting quick release valve which is the proportional pressure reducing control valve 80R is also described in the above-mentioned JP-A-1-1.
As shown in Japanese Patent No. 48650, the internal structure itself is known. The limiting quick release valve 80R has a valve stem 81 inside a housing 800.
0 and a stepped plunger 820, and an exhaust valve 811 is provided at one end of the valve stem 810 and a supply valve 812 is provided at the other end thereof. Then, when traveling on a slippery road surface, the exhaust valve 811 is closed and the supply valve 812 is opened, so that according to the ratio of the pressure receiving area of the stepped plunger 820,
The pressure in the first chamber 821 is reduced as compared with the pressure in the second chamber 821. The housing 800 of such a limiting quick release valve 80R has a follower (brake chamber 51
R), a first outlet 831, a second outlet 832 to be connected to a follower (brake chamber 52R) having a heavier axial load during braking, and an exhaust port 840 communicating with the atmosphere.
There is. By the way, in the limiting quick release valve 80R, the first chamber 821 has the first outlet 831.
In addition, the second chamber 822 communicates with the second outlet 832, but in view of the relationship with the antiskid control valve device 61R, the second chamber 822 and the second outlet 832 must be communicated with the outlet 630. I won't. Therefore, in the example of FIG. 3, this is made possible by using the bolt member 900 in which the T-shaped inlet passage 910 is formed. That is, limiting quick release valve 8
A bolt through hole 850 penetrating laterally is provided in the housing 800 on the 0R side, and the bolt through hole 850 is also provided.
The opening is exposed to the outlet 630 of the housing 600 on the anti-skid control valve device 61R side. Therefore, the ribs 880 of the housing 800 on the side of the limiting quick release valve 80R and the ribs 680 of the housing 600 on the side of the anti-skid control valve device 61R are jointly tightened, for example, while the bolt member 900 is passed through the bolt through hole 850. Anti-skid control valve device 6
A sealing member 9 such as a gasket is provided at the outlet 630 on the 1R side.
Holding 30 and limiting quick release valve 8
The OR and the anti-skid control valve device 61R can be integrally connected. Since there is an inlet passage 910 in the bolt member 900 for connection, the two valve devices can be integrated and piped at the same time.

[0013]

According to the present invention, different axles 41, 4 are provided.
Brake actuators (followers) 51L, 51R; 52L, 5 for the wheels 41L, 41R;
When controlling the pressures of all the 2Rs in common, the followers 51R and 52R provided for the wheel 41, which has a lighter load during braking among a plurality of wheels, and the anti-skid control valve device 6
Proportional pressure reducing control valves 80R and 80L between 1R and 61L
Since the brakes are interposed, the structure of the brake system can be simplified, and an appropriate braking force can be applied to each wheel during antiskid control.

[Brief description of drawings]

FIG. 1 is a diagram showing a first embodiment of a brake system according to the present invention.

FIG. 2 is a diagram showing a second embodiment of the brake system according to the present invention.

FIG. 3 is a diagram showing a third embodiment of the present invention.

[Explanation of symbols]

20 electronic control unit (discrimination circuit) 25 relay emergency valve (main engine) 41L, 41R; 42L, 42R wheels 51L, 51R; 52L, 52R brake chamber (follower) 61R, 61L anti-skid control valve device 71R, 71L Sensor 80R, 80L Proportional pressure reducing control valve

Claims (1)

[Claims] 1. A follower for applying a brake to each of a plurality of wheels arranged in the front-rear direction of a vehicle body is provided,
These followers are connected to a main actuator that sends a brake pressure according to a driver's operation through one brake system, and a sensor mounted on at least one of the plurality of wheels is used. A discriminating circuit for discriminating the skid tendency of the wheel is provided by monitoring the rotation state of the wheel, and the brake pressure is adjusted commonly to all the followers in the one brake system based on a command from the discriminating circuit. In a brake system for a multi-axle trailer provided with an anti-skid control valve device, a follower provided for a wheel of which load during braking becomes lighter among the plurality of wheels, and the anti-skid control valve device, A brake system for a multi-axle trailer with a proportional pressure reducing control valve interposed.