JP3113890B2 - Vehicle drive control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drive control system for a vehicle, and more particularly to a drive control system for a vehicle using a hydrostatic continuously variable transmission to which ABS control is applied.

[0002]

FIG. 3 shows a conventional hydrostatic continuously variable transmission (HS).
T) shows a hydraulic control circuit in a drive control device of a vehicle to be used, 1 is a hydraulic pump driven by an engine, 2
Is a hydraulic motor, and 3 is a propeller shaft driven by the hydraulic motor 2.

In such a conventional vehicle, when the vehicle is moving forward, high-pressure oil of, for example, 400 kg / cm ^{2 is applied} from a hydraulic pump 1 to a hydraulic motor 2 via a high hydraulic line 4 and the oil from the hydraulic motor 2 is removed The swash plate (not shown) of the hydraulic pump 1 is returned to the neutral position and the driving force is released during braking by the brake.

However, in such a case, the hydraulic pressure of the low hydraulic pressure line 5 is 400 k
g / cm ² , and a large braking force acts on the hydraulic motor 2 to lock the wheels. Therefore, the anti-lock braking system (ABS) cannot be operated. 240kg / c
Limit so as not to m ² or more, and to be able to act ABS.

[0005]

However, even in a vehicle in which the hydraulic pressure of the low hydraulic pressure line 5 is limited as described above, A
The BS cannot be operated sufficiently, and the acceleration at the time of reverse movement becomes worse. On the other hand, if the oil pressure in the low oil pressure line 5 is suppressed to, for example, 150 kg / cm ² , the braking force due to the HST during forward movement decreases.

The present invention has been made to eliminate the above disadvantages.

[0007]

A drive control device for a vehicle according to the present invention comprises a two-pressure control valve connected to a low hydraulic line of a hydraulic control circuit of a hydrostatic continuously variable transmission, and a means for detecting the operation of ABS. When the ABS is not operated by operating the two-pressure control valve,
The hydraulic pressure of the low-pressure line to an intermediate pressure, characterized by comprising more control means for controlling to lower the oil pressure at the low pressure line ABS operation further to the low pressure.

[0008]

Embodiments of the present invention will be described below with reference to the drawings.

In the present invention, as shown in FIG.
S means for detecting the operation of the SST, and the two-pressure control valve 7 is connected to the low hydraulic line 5 of the hydraulic control circuit of the vehicle using the HST.
And controls the two-pressure control valve 7 via a solenoid 8 driven by the output of the ABS operation detecting means 6. During the operation of the ABS, the hydraulic pressure of the low oil pressure line 5 is, for example, 150 kg / cm. limited to ² or less, during non-operation of the ABS is to allowed to limit the low pressure line 5 below the 240 kg / cm ^2.

Since the vehicle drive control device according to the present invention has the above-described configuration, it is detected whether or not the ABS is operated when the brake pedal is depressed as shown in FIG.
In a state where S does not operate, the two-pressure control valve 7 is controlled via the solenoid 8 so that the low hydraulic line 5
g / cm ² or less, and only the braking function of the HST is maintained. When the ABS is operated, the low hydraulic line 5 is maintained at a low pressure of 150 kg / cm ² or less. First, the ABS control is sufficiently operated.

[0011]

As described above, according to the vehicle drive control apparatus of the present invention, there is a great advantage that the HST control can be realized without disturbing the ABS operation.

[Brief description of the drawings]

FIG. 1 is a hydraulic control circuit diagram of a vehicle drive control device according to the present invention.

FIG. 2 is an operation explanatory view of the vehicle drive control device of the present invention.

FIG. 3 is a hydraulic control circuit diagram of a conventional vehicle drive control device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Hydraulic pump 2 Hydraulic motor 3 Propeller shaft 4 High hydraulic line 5 Low hydraulic line 6 Operation detecting means 7 2 Pressure control valve 8 Solenoid

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) F16H 61/40-61/46

Claims (1)

(57) [Claims] 1. A two-pressure control valve connected to a low hydraulic line of a hydraulic control circuit of a hydrostatic continuously variable transmission, a means for detecting the operation of ABS, and a non-operation of ABS by operating the two-pressure control valve
When the low hydraulic line pressure of the medium pressure, vehicle drive control apparatus characterized by comprising more control means for controlling so as to reduce the time of ABS operation <br/> Symbol the hydraulic pressure of the low pressure line further to the low pressure .