A method for manufacturing a ferrous rotational member including the steps of turning a first portion of the friction surface at a sufficient feed rate to provide a first deformed layer on the first portion of the friction surface; fine turning a second portion of the friction surface at a sufficient feed rate to provide a second deformed layer on the second portion of the friction surface; burnishing the first and second portions of the friction surface to achieve a predetermined roughness; and nitrocarburizing the rotational member at a time and temperature sufficient for the diffusion of nitrogen atoms and carbon atoms through the deformed layer to form hardened casings having variable thickness. The ferrous rotational member may be that of a brake rotor having a hub surface and a friction surface, where the hub surface and friction surface have a variable thickness hardened casing.

An automatic transmission includes: a frictional engagement element including first and second annular friction plates; a pressing member moving in the axial direction relative to the transmission case and press the frictional engagement element in the axial direction; and a lubricating oil. Further, the transmission case includes a contact portion on the inner wall so that the contact portion is separated from a back surface of the pressing member when the frictional engagement element is in an engagement state and comes into contact with the back surface of the pressing member when the frictional engagement element is in a disengagement state.

A piston configured for use in a brake system is disclosed. The piston can comprise: a body; and a footing; the footing positioned adjacent an end of the body, and having a recess that receives a central portion of the end; during operation of the brake system, the footing extends along a brake pad, and is configured to exert force on the brake pad during actuation of the disk brake system; and the footing having a face configured to contact the brake pad, the face having a length and a width, wherein the length is longer than an outside width of the body, and the length is greater than the width, and/or the face having a cross-sectional area normal to a direction of travel of the piston that is larger than a cross-sectional area of the piston body that is normal to the direction of travel of the piston.

An electronic parking brake device including: a plate part having a brake shoe rotatably mounted thereon; a housing part mounted on the plate part and configured to guide hydraulic pressure; a motor part mounted on the housing part, and driven when power is applied thereto; a piston part mounted on the housing part, and moved by hydraulic pressure so as to operate the brake shoe; and an operation part embedded in the housing part, disposed between the piston parts, and driven by the motor part so as to push the piston parts.

A brake system that includes a brake caliper comprising an inboard side and an outboard side, the inboard side of the brake caliper includes one or more brake pistons and the outboard side of the brake caliper comprises one or more brake pistons, and a brake pad comprising a first pad section and a second pad section. During a service brake apply, both of the first pad section and the second pad section are moved against a braking surface to create a clamping force. During a parking brake apply, only one of the first pad section and the second pad section is moved against the braking surface to create a clamping force. The first pad section comprises a friction material having a coefficient of friction that is different than a coefficient of friction of the second pad section.

A system for determining brake wear based on hydraulic fluid volume may comprise a brake actuator and a fluid supply line fluidly coupled to the brake actuator. The brake actuator may include a brake ram configured to translate in response to changes in fluid pressure in the brake actuator. A piston may be fluidly coupled between a first portion of the fluid supply line and a second portion of the fluid supply line. The piston may include a cylinder and a ram configured to translate within the cylinder. A first sensor may be operably coupled to the piston.

A backup device for a vehicle performs backup of a plurality of drive sources based on power supply from a second power supply unit even when power supply from a first power supply unit stops and reduces the peak voltage necessary in the backup operation. In a backup device, when an abnormal state of the power supply from a first power supply unit is detected, a control unit instructs a discharge unit to intermittently apply a discharge current a plurality of times to each of a plurality of motors and controls a supply destination of the discharge current such that each instruction time period during which the discharge unit is instructed to apply the discharge current to one motor is shifted with respect to each instruction time period during which the discharge unit is instructed to apply the discharge current to the other motor.

A disc brake device has brake linings attached to brake levers that open and close in the lateral direction and sandwich a brake disc. A linking mechanism including a coupling device including lever mechanisms and a spindle opens and closes in conjunction with the lifting and lowering operation of a rod of a thruster, and the spindle is rotated in one direction by a one-way clutch in accordance with the relative displacement between the lever mechanisms and the coupling device to shorten an overall length of the coupling device, the rotation of the spindle is transmitted to an adjustment bolt screwed to a stopper on the lower end sides of the left and right brake levers via a flexible shaft, and the adjustment bolt protrudes downward with respect to the stopper.

A brake assembly comprising: (a) a caliper including: (i) one or more pistons, (b) one or more rotary to linear actuators that provides an axial force to move the one or more pistons, (c) a motor gear unit in communication with the one or more rotary to linear actuators, the motor gear unit including: (i) a motor, and (ii) an electromagnetic brake that prevents movement of the motor gear unit, the pistons, or both when the motor is turned off so that the brake apply is maintained.

The electric-powered actuator includes a control device including: a motor angle estimation unit, and a reverse-input holding control section having a function of engaging an engaging part with an engaged part by controlling a solenoid to set the reverse-input holding mechanism into a reverse-input holding state while the electric-powered actuator is applying a load and a function of, from the reverse-input holding state, disengaging the engaging part from the engaged part to set the reverse-input holding mechanism into a reverse-input holding release state. The reverse-input holding control section includes an engagement intermediate control function section configured to control the estimated rotation angle such that the engaged part and the engaging part come into a predetermined positional relation within a certain period of time, when the engaging part is brought into engagement with the engaged part and when the engaging part is brought out of engagement with the engaged part.