Toyota Jidosha Kabushiki Kaisha

Advics Co., Ltd.

Hiroaki Endo

Ryochi Watanabe

Yoshihisa Yamada

Hiroyuki Kano

Taro Hirose

Masaki Kinoshita

Shirou Monzaki

This automatic clutch control device selects a normal mode when a road friction coefficient is not less than 0.3 at a disconnecting operation starting point (time t), selects a little low-speed mode when it is not less than 0.1 but less than 0.3 and selects a low-speed mode when it is less than 0.1. Further, when a vehicle stabilizing control such as a traction control or the like is not executed at the time t, this device selects the normal mode, while when a vehicle stabilizing control is executed at the time t, it selects the low-speed mode. Moreover, this device selects a high-speed mode when the vehicle is in a sports running mode at the time t, while selects the normal mode when the vehicle is not in the sports running mode. A connecting operation of a clutch is performed with a speed corresponding to the selected mode in an automatic clutch connecting/disconnecting control by a clutch connecting/disconnecting actuator upon executing a gear-shift control.

Automatic clutch control device

The automatic clutch control device controls, regardless of the gear-shift operation, the clutch to be brought into a half-clutch state or to a perfect disconnecting state according to a running state of a vehicle from the following five viewpoints deceleration slip amount of driving wheels RL and RR; a convergence time of a driving wheel speed to the driving wheel in a pressure-down mode during a vehicle stabilizing control (for example, ABS control); a continuation time of a judder vibration; whether the vehicle is in a spinning state or not; and whether there is a possibility that an engine stall occurs during a traction control. As a result, this device can attain at least one or more objects of the improvement in stability of the vehicle, improvement in precision of the vehicle stabilizing control, improvement of comfortableness of the occupant and prevention of the occurrence of the engine stall.

In a brake system of a four-wheel vehicle having a powered fluid pressure source, fluid flow control circuit including control valves, and an automatic controller for selectively operating the powered fluid pressure source and the control valves so as to supply a controlled fluid pressure based upon the powered fluid pressure source to a selected one or more of the wheel cylinders for an execution of a behavior control of the vehicle according to running conditions of the vehicle, the automatic controller also executes a brake control of supplying a controlled fluid pressure based upon the powered fluid pressure source to at least one of the wheel cylinders according to a depression of a brake pedal by a driver during the execution of the behavior control, the at least one wheel cylinder being one or more of the wheel cylinders not selected for the behavior control.

Brake system of vehicle for simultaneous execution of driver's braking and automatic behavior control

A negative pressure control apparatus for a brake booster is provided which can always maintain a required negative pressure in a negative pressure chamber of the brake booster in a system including a direct-injection engine. The apparatus has a brake operation predicting part for predicting execution of a brake operation by a driver. When execution of a brake operation is predicted, negative pressure in the negative pressure chamber is controlled to be a required value.

Negative pressure control apparatus for brake booster

A negative pressure control apparatus for a brake booster for controlling a negative pressure in a negative pressure chamber of the brake booster is provided. The apparatus is applied to a system having a booster charge mechanism for generating a fluid pressure by using the negative pressure in the negative pressure chamber and a fluid pressure control mechanism for controlling a brake fluid pressure by using the fluid pressure generated by the booster charge mechanism as a fluid pressure source. The apparatus includes a negative pressure controller for controlling the negative pressure in the negative pressure chamber to be at least a predetermined target negative pressure. A temperature detector detects information relating to a temperature of brake fluid. A target negative pressure setting part sets the predetermined negative pressure based on the temperature of the brake fluid.

A negative pressure control apparatus for a brake booster is provided which can maintain a required negative pressure in the brake booster without unnecessarily increasing the negative pressure of the brake booster. The apparatus has a negative pressure controller for controlling the negative pressure in a negative pressure chamber of the brake booster toward a predetermined target value. A pedal operation determining part determines whether or not both an accelerator pedal and a brake pedal are depressed. When both the accelerator pedal and the brake pedal are depressed, a target negative pressure setting part sets the predetermined target value to be larger than a value used in a regular situation.

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Shizuoka-ken, Japan

Hiroaki Endo