JP2001278030A - Turning movement stabilizing device for tractor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a turning movement stabilizing device for a tractor, for controlling the operation of an auxiliary braking device in turning in a trailer towed on a low friction road surface such as a snowy road. SOLUTION: This turning movement stabilizing device for a tractor is constituted of a steering angle sensor 5 provided on a steering device 4 and for detecting the steering angle, a yaw rate sensor 7 provided in the central part in the longitudinal direction of a vehicle 1 and for detecting the yaw angle of the vehicle 1, a slip detecting means 40 for detecting the slip state of a driving wheel Wr, an auxiliary braking device switch 10 for switching the operation of an auxiliary braking device 8 to a snow mode or a dry mode, and a control means 9 for performing OFF control of the auxiliary braking device 8 by receiving an output signal from the auxiliary braking device, an output signal from the steering angle sensor 5, an output signal from the yaw rate sensor 1, and an output signal from the slip detecting means 40. The auxiliary braking device 8 is turned off in turning on a low friction road surface such as a snowy road to avoid a jack knife phenomenon.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a turning stabilizing device for a tractor for an articulated vehicle provided with an auxiliary braking device.
The present invention relates to a tractor turning stabilizing device that performs OFF control of an auxiliary braking device.

[0002]

2. Description of the Related Art When traveling on a low friction road surface such as a snowy road in a connected state, when an auxiliary braking device of a tractor is operated, a driving wheel is locked and a trailer pushes the tractor so-called deceleration slip. It can be a source of instability. In particular, there is a concern that the operation of the auxiliary braking device during turning may cause a jackknife phenomenon.

Japanese Unexamined Patent Publication No. Hei 9-4483 discloses a control technique when a drive wheel of a vehicle provided with a traction control device slips. However, this technology is a technology for preventing deceleration slip of a drive wheel due to downshifting at the time of high-speed traveling on a single vehicle and acceleration slip during acceleration, and the control is performed by increasing or decreasing the torque of the drive wheel. The control of the braking device is different from the vehicle configuration and the control target.

Japanese Patent Application Laid-Open Nos. Hei 8-11689 and Hei 9-136634 disclose the braking force control of a connected vehicle having an auxiliary braking device. In each case, braking control including a trailer braking device is performed. And the device and control are complicated.

Further, Japanese Patent Application Laid-Open No. Hei 8-5305 by the present applicant
In Japanese Patent Application Publication No. 9-204, the operation of the auxiliary braking device is released or prohibited according to the conditions of the coupler switch and the transmission position, which is different from the present invention.

[0006]

SUMMARY OF THE INVENTION The present invention has been proposed in view of the above-mentioned problems of the prior art, and relates to a turning stabilizing device for a tractor for a connected vehicle, and more particularly to a trailer on a low friction road surface such as a snowy road. An object of the present invention is to provide a tractor turning stabilization device that performs OFF control of the operation of an auxiliary braking device when turning during towing.

[0007]

According to the present invention, there is provided a tractor turning stabilizer for a tractor having an auxiliary brake device such as an exhaust brake other than a service brake, an engine brake by operating an exhaust valve, and a retarder. In the device, a steering angle sensor provided in the steering device for detecting a steering angle, a yaw rate sensor provided in a central portion in the vehicle front-rear direction and detecting a yaw angle of the vehicle, a slip detection means for detecting a slip state of the drive wheels, An auxiliary braking device switch for switching the operation of the auxiliary braking device in accordance with the road surface condition; receiving an output signal of the auxiliary braking device switch, an output signal of a steering angle sensor, an output signal of a yaw rate sensor, and an output signal of a slip detecting unit. And control means for performing OFF control of the auxiliary braking device.

As described above, the turning angle of the vehicle is determined by detecting the steering angle and the yaw angle. At the time of turning, the operation of the auxiliary braking device is turned off to prevent the driving wheels from slipping. I try to avoid it.

The driver can manually switch the auxiliary braking device switch to snow or dry depending on the road surface condition.

According to the above, when the snow of the auxiliary braking device switch is selected on a snowy road, the control device judges the vehicle posture, and if the vehicle is turning, the operation of the auxiliary braking device is turned off to perform a safe turning. If the vehicle is going straight, the auxiliary braking device can be operated to perform a smooth deceleration operation. Also,
On a road surface with normal friction, it is possible to select a dry state and operate the auxiliary braking device to smoothly run at a reduced speed.

The slip detecting means makes a judgment based on a difference between the rotational speed of the drive wheel and the rotational speed of the drive wheel obtained from the vehicle speed.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the drawings, an embodiment of a tractor turning stabilizer according to the present invention will be described below. FIG.
1 shows a block configuration of a tractor turning stabilizer according to the present invention. A description will be given with reference to a mounting diagram of the device on an actual tractor vehicle in FIG. Reference numeral 2 in FIG. 2 indicates a connected trailer. In FIG. 2, the trailer 2 is a semi-trailer, but may be a full trailer.

The steering angle sensor 5 is mounted on the steering device 4 of the vehicle, and the output signal is connected to the control device 9 via a signal line 5a.

The yaw rate sensor 7 is mounted at a central portion in the longitudinal direction of the vehicle so as to detect one or more yaw angular velocities to obtain a yaw angle. And it is connected to the control device 9 via the signal line 7a. The conversion of the yaw rate signal to the yaw angle is usually performed in the control device 9 by a known method.

The auxiliary brake device switch 10 is mounted in the driver's cab 3 and is manually operated by a driver. One is for low friction road surfaces such as snowy roads and ice vans, and the other is for dry road surfaces. It is designed to switch. And it is connected to the control device 9 by a signal line 10a. In a tractor provided with an electronically controlled brake, the auxiliary brake device switch 10 can be operated when it is detected that the road surface friction coefficient is low.

The slip detecting means 40 will be described with reference to FIG. The slip detection means 40 includes a drive wheel rotation speed detection means 31 for detecting a rotation speed V1 of a rear wheel Wr which is a drive wheel of the tractor, a vehicle speed detection means 32 for detecting a vehicle speed Vo, and a slip from the vehicle speed Vo. A drive wheel speed calculating means 34 for calculating the drive wheel rotational speed V2 without the drive means, and a slip determining means 35 for comparing the results of the two means 31 and 34 to determine the slip state of the drive wheel Wr.

As described above, the slip determination means 35
The slip is determined by comparing the drive wheel rotation speed V1 with the drive wheel rotation speed V2 calculated from the vehicle speed Vo. However, in practice, the operation of the auxiliary braking device 8 during turning is always performed by the vehicle. Since the drive wheel speed V2 without slip calculated from the speed does not become lower than the drive wheel speed V1 actually measured and detected, only the deceleration slip is determined. The slip detecting means 40 is connected to the control device 9 via a signal line 40a.
It is connected to the.

The control device 9 receives signals from the steering angle sensor 5, the yaw rate sensor 7, the auxiliary brake device switch 10, and the slip detection means 40, and calculates and compares the data with various built-in data and a calculation program to control lines. It is configured to have a function of controlling the auxiliary braking device 8 via 8a.

The operation of the tractor turning stabilizing device having the above-mentioned structure when the auxiliary brake device switch 10 is not used will be described with reference to the flowchart of FIG. The case where the auxiliary braking device switch 10 is used will be described later with reference to the flowchart of FIG.

In step S1, it is determined whether or not the auxiliary braking device 8 is in the ON state in which the operation is enabled. If NO is inactive, including manual operation, the turning braking is safe, and the auxiliary braking device 8 in step S3 is selected to always be inactive, and the process returns to step S1. Auxiliary braking device 8 is operable ON
If YES, go to step S2.

In step S2, the driving wheel rotation speed V1 is detected. If the drive wheel Wr has slipped, for example, in deceleration, the drive wheel rotation speed V1 is detected to be lower than the rotation speed calculated from the actual speed. Next, the procedure goes to step S4.

In step S4, the vehicle speed Vo is detected by a known means. Next, the procedure goes to step S5.

In step S5, a desired drive wheel rotation speed V2 without slip is calculated from the vehicle speed Vo. Then, the procedure goes to step S6.

In step S6, it is determined whether or not a deceleration slip has occurred. If the drive wheel rotational speed Vo without slip should be greater than the drive wheel rotational speed V1 and YES, a deceleration slip has occurred, and the process goes to step S7. If the deceleration slip has not occurred, the process proceeds to step S8 with NO, the auxiliary brake device can be operated at all times, and the process returns to step S1.

In step S7, a steering angle and a yaw angle for judging the vehicle attitude are detected. Then, go to step S8.

In step S9, it is determined whether the vehicle is traveling straight or turning based on the steering angle or the yaw angle. If the steering angle exceeds 0 degrees, the vehicle is in a turning start-turning state, and if the yaw angle exceeds 0 degrees, the vehicle attitude is also in a turning state. As a result of the determination in step S9, the vehicle travels straight Y
If it is ES, go to step S10. Also, go straight NO
If it is the turn, go to step S11.

In step S10, since the vehicle is traveling straight, the auxiliary braking device 8 is made operable. And it enables smooth straight running to activate the auxiliary braking. Then
Go to step S12.

In step S11, the auxiliary braking device 8 is always deactivated. Then, the occurrence of the deceleration slip is avoided. Then, the procedure goes to step S12.

In step S12, it is determined whether the control of the auxiliary braking device 8 is to be continued. If the control is to be continued, NO is returned to step S1.
If S, the process ends.

Next, the case where the auxiliary braking device switch 10 is used will be described with reference to the flowchart of FIG. In step S21, it is determined whether or not the auxiliary braking device 8 is in the ON state where the operating state is enabled. If NO, the turning braking is safe, and the auxiliary braking device 8 in step S23 is selected to be always inoperative, and the process returns to step S21. If the operation of the auxiliary brake device 8 is YES, the process proceeds to step S
Go to 22.

In step S22, it is confirmed whether or not the driver has selected the auxiliary braking device switch 10 to select the snowy road surface condition. If the driver has selected snow (step S22 is YES), the process proceeds to step S24, and if the driver has selected the dry road condition of normal friction (step S22 is NO), the process proceeds to step S25 to perform auxiliary braking. The apparatus 8 is made operable at all times to enable smooth deceleration traveling, and the process returns to step S21.

In step S24, a steering angle and a yaw angle for determining the vehicle attitude are detected. Then, the procedure goes to step S26.

In step S26, it is determined whether the vehicle is traveling straight or turning based on the steering angle or the yaw angle. If the steering angle exceeds 0 degrees, the vehicle is in a turning start-turning state, and if the yaw angle exceeds 0 degrees, the vehicle attitude is also in a turning state. If it is determined in step S26 that the vehicle is traveling straight, the process proceeds to step S27. On the other hand, if the vehicle is turning straight, the process goes to step S28.

In step S27, since the vehicle is traveling straight, the auxiliary braking device 8 is made operable. And it enables stable straight running. Then, the procedure goes to step S29.

In step S28, the auxiliary braking device 8 is always deactivated. Then, the occurrence of the deceleration slip is avoided. Then, the procedure goes to step S29.

In step S29, it is determined whether or not the control of the auxiliary braking device 8 is to be continued. If the control is to be continued, the determination is NO and the process returns to step S21.
If it is ES, the processing ends. As described above, in each of FIGS. 4 and 5, when turning on a low friction road surface such as a snowy road, the operation of the auxiliary braking device 8 is controlled to OFF to prevent the jackknife phenomenon due to deceleration slip. .

[0037]

The effects of the present invention are described below. (1) With the tractor turning stabilization device of the present invention, the auxiliary brake device is turned off during turning to avoid slipping of the drive wheels, and the jack knife phenomenon caused by pushing the trailer can be avoided. (2) If the switch of the auxiliary braking device is operated in the snow state manually, the vehicle posture is detected, and if the vehicle is traveling straight, the auxiliary braking device is operated to smoothly reduce the speed. The operation can prevent the occurrence of the jackknife phenomenon.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of a tractor turning stabilizer according to the present invention.

FIG. 2 is an explanatory diagram showing mounting of the sensors, devices, and the like in FIG. 1 on an actual vehicle.

FIG. 3 is a block diagram of a slip detecting unit.

FIG. 4 is a flowchart illustrating a case where the operation of the tractor turning stabilization device of FIG. 1 is determined based on a drive wheel slip to control an auxiliary braking device.

FIG. 5 is a flowchart in the case where the operation of the tractor turning stabilization device of FIG.

[Explanation of symbols]

 Wf: driven wheel (front wheel in this example) Wr: drive wheel (rear wheel in this example) 1 tractor 2 trailer 3 driver's cab 4 steering device 5 steering Angle sensor 5a ... signal line 7 ... yaw rate sensor 7a ... signal line 8 ... auxiliary braking device 8a ... control line 9 ... control device 10 ... auxiliary braking device switch 10a ... control line 31 ··· Drive wheel rotational speed detecting means 32 ··· Vehicle speed detecting means 34 ··· Drive wheel speed calculating means 35 ··· Slip determining means 40 ··· Slip detecting means 40a ··· signal line

Claims (3)

[Claims] 1. A turning stabilizing device for a tractor for a connected vehicle provided with an auxiliary braking device, comprising: a steering angle sensor provided in a steering device for detecting a steering angle; and a yaw angle of a vehicle provided in a central portion in a vehicle longitudinal direction. A yaw rate sensor for detecting, a slip detecting means for detecting a slip state of the drive wheel, an auxiliary brake device switch for switching the operation of the auxiliary brake device according to a road surface condition, an output signal of the auxiliary brake device switch, and a steering angle sensor Control means for receiving the output signal of the yaw rate sensor, the output signal of the yaw rate sensor, and the output signal of the slip detecting means, and performing OFF control of the auxiliary braking device. 2. The tractor turning stabilizer according to claim 1, wherein the driver manually switches the auxiliary braking device switch to snow or dry depending on the road surface condition. 3. The tractor turning stabilizing device according to claim 1, wherein said slip detecting means determines the difference between the rotational speed of the drive wheel and the rotational speed of the drive wheel obtained from the vehicle speed.