Antiskid device

Claim 1

An antiskid device for a braking oil system in an automotive vehicle comprising braking means for braking front and rear wheels and including a brake pedal, a master cylinder hydraulically actuated by said brake pedal and for generating oil pressure, front and rear wheel cylinders, and conduits connected therebetween, hydraulic pressure control means for controlling the operation of said braking means and including an inlet and outlet for braking oil, said inlet being connected through a conduit with said master cylinder, said outlet being connected through a conduit with the rear wheel cylinders, a plunger having an oil seal for preventing oil from leaking, a check valve including an inlet for oil, a ball valve, a ball valve seat, and a spring for urging the valve so as to close it, and a diaphragm chamber assembly having an air chamber and a vacuum chamber, a diaphragm urged by the plunger from said air chamber to said vacuum chamber, and a spring disposed within said vacuum chamber to urge said diaphragm to said air chamber, air pressure control means for controlling the air pressure to said hydraulic pressure control means and including a solenoid valve having a solenoid coil, a valve and a spring for urging the valve to close, two relief valves each having a valve, a spring for urging said valve to close and a spring adjusting screw, the spring chamber of said solenoid valve being connected to said air chamber of said hydraulic pressure control means through a conduit, said first relief valve being mounted adjacent to said solenoid valve and connected to the atmosphere through a conduit and an air cleaner, said second relief valve being connected to an intake manifold of the engine through a conduit and with the vacuum chamber through a conduit, solenoid valve means for providing a passage between said air cleaner and said air chamber of said diaphragm chamber assembly in said hydraulic pressure control means and including a solenoid coil, a valve and a spring for urging the valve to close, and skid-detecting means for detecting the rotation of right and left-hand wheels and including two rotors on which teeth are provided, two electromagnetic pickup means each for generating pulses proportional to the revolutions of said rotors, two shapers for generating square electrical waves in response to said pulses derived from said pickup means and connected electrically therewith, two speed detecting means each for detecting the speeds of said rotors and connected electrically with said shapers, respectively, two deceleration detecting means for detecting the deceleration of said rotors, respectively, a first Schmitt circuit means for high deceleration of the right-hand wheels, a second Schmitt circuit means for low deceleration of the right-hand wheels, a third Schmitt circuit means for high deceleration of the left-hand wheels, a fourth Schmitt circuit means for low deceleration of the left-hand wheels, said first and second Schmitt circuit means being connected with said first deceleration detecting means, said third and fourth Schmitt circuit means being connected with said second deceleration detecting means, a first OR circuit means receiving the outputs from said first and third Schmitt circuit means for generating a voltage only when either output is supplied thereto, a second OR circuit means receiving the outputs from said second and fourth Schmitt circuit means for generating a voltage only when either output is supplied thereto, a first power-amplifying means receiving the output from said first OR circuit means for amplifying it, a second power-amplifying means receiving the output from said second OR circuit means for amplifying it, a constant voltage means for producing a constant voltage to all previous circuit means, a first solenoid coil conneCted with said first power amplifying means, a second solenoid coil connected with said second power amplifying means, a first safety switch connected in parallel with said first power amplifying means for actuating when an overload is applied to the amplifying means, a second safety switch connected in parallel with said second power amplifying means for actuating when an overload is applied to the amplifying means.