Honda Motor Co., Ltd.

Nissin Kogyo Co., Ltd.

Autoliv Nissin Brake Systems Japan Co., Ltd.

Arata Inoue

Kunimichi Hatano

Takaaki Ohnishi

Kazuyoshi Akutsu

Kazuaki Murayama

Takashi Nishioka

Naoto Ohkubo

Takehiro Horiuchi

Kaoru Akahane

Toru Mabuchi

Makoto Sawai

Tomoya Toyohira

Kenji Hattori

Nobuyuki Kobayashi

Hidetoshi Kobori

Hideo Miyabayashi

Nobutake Hyodo

Osamu Adachi

Kentarou Tanaka

An input device of a vehicle brake system which is downsized and has an improved general versatility in comparison with conventional vehicle brake systems is provided. An input deviceincludes: a master cylinderthat produces a fluid pressure in accordance with an input of an operation of a brake operating member; and a stroke simulatorwhich is provided side by side with the master cylinderand which applies in a pseudo manner a force counteracting the operation of the brake operating memberto the brake operating member. The master cylinderand the stroke simulatorare formed integrally.

Input device of vehicle brake system

Untreated bosses are formed in advance in two directions on a cylinder mechanism. The bosses on one side are formed as mounts to attach a motor cylinder device to a vehicle body, and the other bosses are formed as ports to connect to the cylinder mechanism. The mount bosses are formed on the outside in the width direction of the vehicle, and the port bosses are formed on the inside in the width direction of the vehicle.

Vehicle-body attachment structure for electric brake actuator

An input device of a vehicle brake system integrally includes an integrally provided master cylinder and a stroke simulator which communicate via a hydraulic communication path. The stroke simulator is provided with a simulator piston accommodated within a simulator accommodation chamber. The simulator accommodation chamber has an opening portion enabling the insertion of the simulator piston into the simulator accommodation chamber from the side on which the brake pedal is disposed relative to the dashboard.

Vehicle brake system

A motor cylinder device () is configured with a cylinder mechanism () provided with first and second slave pistons that are displaced along a hydraulic pressure chamber; an electric motor () for driving first and second slave pistons; and an actuator housing () formed separable from the cylinder mechanism (), wherein the actuator housing houses a gear mechanism for transmitting a rotational driving force of the electric motor (), and a conversion mechanism for converting the rotational driving force transmitted through the gear mechanism, into a linear movement and transmitting the linear movement to the piston.

Electric brake actuator, and brake system for vehicle

A structure for attaching a motor cylinder device to the body of the vehicle, said vehicle brake system including: an input device via which an operator inputs brake operations; and a motor cylinder device that generates hydraulic brake pressure on the basis of electrical signals based on said brake operations. Said motor cylinder device has: an electric motor that operates on the basis of electrical signals; a driving-force transmission unit that transmits driving force from the electric motor; and a cylinder mechanism that applies pressure to a brake fluid by moving a piston axially by means of the driving force transmitted by the driving-force transmission unit. A mount for attaching the motor cylinder device to the body of the vehicle is provided near the center of gravity of the motor cylinder device. This makes it possible to minimize displacement of the electric brake actuator when subjected to vibration.

Under a normal condition, brake fluid pressure generated by a slave cylinder () that operates according to operation of a brake pedal () is fed to a wheel cylinder () to perform braking, while under a fault condition of the slave cylinder (), brake fluid pressure generated by a master cylinder () for backup that operates by the operation of the brake pedal () is fed to the wheel cylinder () to perform braking. In the latter case, brake fluid fed by a pump () is fed to the wheel cylinder (), before the brake fluid is fed from the master cylinder () to the wheel cylinder () by a driver depressing the brake pedal (). Accordingly, without leading to an increase in the stroke of the brake pedal (), a required amount of brake fluid can be fed to the wheel cylinder () to thus ensure a sufficient braking force.

Braking device

In an electric braking device that produces brake fluid pressure by driving a second slave piston in the axial direction with the driving force by a motor, a driving force transmission mechanism for transferring the driving force by the motor includes a nut that rotates upon reception of the rotational driving force by the motor, and a ball screw shaft which is engaged with the nut and is movable in the axial direction and which abuts the second slave piston. The electric braking device further includes a worn-out reducer for reducing the worn-out of a contact part between the ball screw shaft and the second slave piston.

Electric braking device

In a brake-by-wire vehicle brake system that uses a solenoid shut-off valve (), the electric power supplied to the solenoid () of the solenoid shut-off valve is controlled so as to decelerate a movement of a plunger () of the valve as the plunger reaches a point immediately adjacent to a terminal point thereof. Thereby, a highly responsive property can be achieved while the noises that are generated by the plunger striking a stopper () or a valve seat () can be minimized. When actuating the plunger in the valve closing direction, the solenoid may receive electric power at a first level, a second level lower than the first level and a third level intermediate between the first and second levels in that order.

In a BBW type vehicle brake device, first and second fluid paths that are connected to each other are both connected to a slave cylinder with a simple structure that is equipped with a single fluid pressure chamber, thereby enabling wheel cylinders having two lines to be operated and eliminating the need for a complicated tandem type slave cylinder. When the slave cylinder becomes inoperable due to malfunction of the power supply, by opening first and second master cut valves and closing the communication control valve, braking is carried out by means of brake fluid pressure generated by a master cylinder. In this process, since the interconnection between the first and second fluid paths is blocked by closing the communication control valve, even if the wheel cylinder of one of the brake lines suffers from a liquid leakage malfunction, the other remained brake line is enabled to ensure a braking force.

Vehicle brake device and vehicle brake device control method

A vehicular hydraulic-pressure-generation device wherein a first bush compressively deforms due to pressure from a simulator piston that moves when hydraulic pressure produced when a brake pedal is depressed is transmitted into a cylinder part. Said vehicular hydraulic-pressure-generation device thus creates artificial reaction-force characteristics with respect to the position of the brake pedal. The aforementioned first bush has a third elastic modulus, which is smaller than a second elastic modulus, and is provided in parallel with a first return spring. The compressive deformation of the first bush occurs over a second region that overlaps a first region in which compressive deformation of the return spring primarily occurs. This makes the brake pedal move more smoothly, reducing the feeling of incongruity resulting from a V-shaped singularity in the reaction-force characteristics with respect to brake pedal position.

Vehicular hydraulic-pressure-generation device and vehicular braking-force generation device

Brake apparatus () includes a transmission unit () for operatively connecting a brake pedal () to a master cylinder (), and the transmission unit is capable of varying a ratio between an output amount of a push rod () connected to a master cylinder () and a movement amount of the brake pedal (). Further, the transmission unit () is constructed such that, in a latter-half operation amount region (E; E; E) of the brake pedal, the ratio of the operation amount of the brake pedal to the movement amount of the push rod is controlled, via the transmission unit, to increase in response to increase of the operation amount of the brake pedal.

Brake apparatus

The following are provided: an input device via which an operator inputs brake operations; a motor cylinder device that generates hydraulic brake pressure on the basis of electric signals based on said brake operations; and a VSA device that assists in stabilizing the behavior of the vehicle on the basis of the aforementioned hydraulic brake pressure generated by the motor cylinder device. Said input device, motor cylinder device, and VSA device are disposed, separated from each other, in an engine compartment partitioned off forwards of a dashboard.

A vehicle brake mechanism includes a master cylinder operated with a brake pedal. A first fluid channel connects a first hydraulic chamber of the master cylinder to a first-circuit wheel cylinder. A second fluid channel connects a second hydraulic chamber of the master cylinder to a second-circuit wheel cylinder. A master cut valve is provided in the first fluid channel and is capable of hindering communication between the first hydraulic chamber and the first-circuit wheel cylinder. A slave cylinder is connected to the second fluid channel and is driven by an actuator to generate a hydraulic pressure. A third fluid channel is provided downstream of the master cut valve and the slave cylinder and connects the first fluid channel and the second fluid channel to each other. A connection control valve is provided in the third fluid channel to close the third fluid channel.

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Saitama, Japan

Arata Inoue