Since vehicles first began to move, stopping safely has been a priority. Hitachi Automotive Systems Americas, Inc., Inc.is one of the first companies to develop vacuum boosters with mechanical brake assist device (2-Ratio Vacuum Booster). We continue to push future brake technology to new levels. Recently, Hitachi Automotive Systems Americas, Inc. developed its own electromechanical brake system as the brake system of the future. This will have the same brake functions as the electrohydraulic brake-by-wire, which are conventional brake functions and all the brake control functions, including antilock brake system (ABS) stability control, brake assist, and autonomous intelligent cruise control. It will also be possible to have additional functions such as electric parking braking. There are many other advantages to the new system: less space is required in the engine and the driver’s compartment; it is more environmentally-friendly because no brake fluid is needed; it has a potentially better pedal feel; it can be operated by means of a joystick. All the necessary technologies for the electromechanical brake system, namely conventional disc brake technologies, electric and electronic technologies, communication technologies, control technologies; and wire-harness technologies are available.
Realization of Front Disc Brake Caliper to satisfy low noise, light-weight and low dragging performance. The caliper regulates the deceleration of the disc fixed to the wheel by adjusting the thrust force acting on the pads via the reduction gear mechanism and the rotational-rectilinear motion conversion mechanism by controlling the current of the motor stator and then the rotation of the motor rotor.
As an alternative brake actuation, Hitachi Automotive Systems Americas, Inc. has been the first in the world to develop and commercialize its own electric brake actuator that uses a servo mechanism that does not rely on vacuum from the engine. Instead an electric motor assists the pedal force provided when the driver operates the brake pedal. Hitachi Automotive Systems Americas, Inc. has been improving e-ACT cost and performance. This electrically assisted actuation (e-ACT) includes a function for working in cooperation with the regenerative brake on an HEV or EV. To improve fuel economy, safety, and driving comfort, Hitachi Automotive Systems Americas, Inc. is developing and promoting low-cost e-ACT products that feature small size, light weight, and ease of installation to allow this technology to be utilized by a larger number of vehicle models in the future.
There is an ongoing trend toward the use of electric parking brakes (e-PKBs) with the aim of providing simpler operation and greater flexibility in interior layout. To make automatic parking brakes possible, Hitachi has minimized brake noise, increased the speed with which the parking brake can be released, and adopted its own actuators, which combine transmission efficiency with an ability to maintain clamping force. Through these initiatives, Hitachi Automotive Systems Americas, Inc. is considering safety and the environment by reducing the weight of the overall brake system, making the calipers and motor smaller and lighter, and also ensuring that the system works with idling stop systems and collision prevention and minimization systems.