Abstract: A power steering system makes use of an electric motor to produce an auxiliary torque added to the torque which is applied to the steering wheel of a vehicle by the driver. The system includes a motor driver for driving the motor and a motor braking circuit for braking the motor. When the torque manually applied to the steering shaft of the vehicle is greater than a predetermined reference torque, an electronic control apparatus causes the motor driver to energize the motor according to the difference between these two torques. When the former torque is less than the reference torque, the control apparatus causes the motor braking circuit to brake the motor. In this way, the torque that the driver of the vehicle must apply to steer the vehicle is maintained equal to the reference torque, irrespective of the vehicle velocity. The reference torque is set by means of a variable-resistor.

Abstract: A power steering system uses an electric motor to produce an auxiliary torque which is added to the torque applied to the steering wheel of a vehicle by the driver. The torque applied by the driver is detected by sensors. The system includes a control apparatus to control the operation of the motor according to the output signal from the sensors. The system further includes a closed electrical loop for feeding a signal corresponding to the output from the motor back to the input side of the loop. A variable-resistor is placed so that the amplification factor of an amplifier included in the loop can be changed by the resistor. The knob attached to the variable-resistor is disposed on the dashboard of the vehicle such that it can be reached by the driver's hand. This permits the driver to change the servo ratio, i.e., the ratio of the output torque of the power steering system to the input torque applied by the driver, while the vehicle is in motion.

Abstract: The steering power transmitting equipment of the present invention comprises a steering gear mechanism having a steering wheel, an upper steering shaft, lower steering shaft and steering gear box, the steering gear mechanism having a torque sensor fixed on the upper steering shaft, a bracket disconnectably fixed to the steering gear box, an electric motor supported on the bracket, a driven gear which is driven by the electric motor and fixed coaxially to the lower steering shaft and an electric controller. The electric controller controls the rotating speed and rotating direction of the electric motor corresponding to the torque and the torque direction inputted by the torque sensor. The power steering gear mechanism is easily mounted on or demounted from standard manual steering equipment without requiring any large scale remodelling of the steering equipment.

Abstract: A power steering system makes use of a direct-current servomotor to produce an auxiliary torque added to the torque which is applied to the steering wheel of a vehicle by the driver. The system includes an electronic apparatus, which receives a signal indicating the velocity of the vehicle, divides the whole range of the vehicle velocity into at least three ranges, and determines under which of these ranges the present velocity falls. In the lowest range, the control apparatus energizes the motor to produce such an auxiliary torque. In the middle range, the apparatus de-energizes the motor and so no auxiliary torque is generated. In the highest range, the apparatus connects a load such as a resistor with the coil in the motor to brake the rotation of the steering wheel.

Abstract: An aluminum alloy for casting purposes contains over 6% and up to 13% by weight of silicon, over 2% and up to 5% by weight of copper, over 0.25% and up to 1% by weight of magnesium, over 0.1% and up to 0.5% by weight of nickel, and over 0.03% and up to 1% by weight of antimony, in addition to aluminum and impurities. The copper and magnesium have a ratio by weight of about 3:1 to 8:1.

Abstract: A cast article of aluminum alloy is produced by pouring into a mold a molten Al-Si-Mg type casting alloy having an antimony (Sb) content in the range of about 0.03%-1.0% by weight and, while the alloy cast body is cooling following complete solidification but before its temperature has fallen below 450.degree. C., placing the solidified cast body into a heating furnace kept at temperatures in the range of from 500.degree. to 550.degree. C. and retaining it at an intermediately high-temperature within that temperature range for not more than 30 minutes, subsequently quenching said cast body in cold water or hot water and thereafter subjecting the quenched cast body to a conventional artificial aging treatment.The resulting cast articles are, in terms of strength, toughness and resistance to thermal shocks, comparable with or superior to cast articles obtained by conventional methods but can be manufactured in a reduced period of time with consequential savings in cost.

Abstract: A cast article of aluminum alloy is produced by pouring into a mold a molten Al-Si-Cu type or Al-Si-Cu-mg type casting alloy having an antimony (Sb) content in the range of about 0.03%-1.0% by weight and, while the alloy cast body is cooling following complete solidification but before its temperature has fallen below 450.degree. C., placing the solidified cast body into a heating furnace kept at temperatures in the range of from 480.degree. to 530.degree. C. and retaining it at an intermediately high-temperature within that temperature range for not more than two hours, subsequently quenching said cast body in cold water or hot water and thereafter subjecting the quenched cast body to a treatment for artificial aging at temperatures in the range of from 140.degree. to 230.degree. C. for a period in the range of from one to 12 hours.