Abstract: A newly obtained wheel speed of a drive wheel is not used in a calculation for acceleration slip when a vehicle is stopped, for example, when the wheel speed of a rolling wheel is zero and an engine speed is high. A wheel speed calculated before a previous wheel speed is, for example, set as a current wheel speed. In this manner, even if the wheel speed of a driving wheel is due to the effect of racing noise, it is possible to limit erroneous determinations that indicate acceleration slip is being generated, based upon such a wheel speed. In addition, unnecessary execution of a traction control can also be curbed.

Abstract: A vehicle speed is obtained from detection signals obtained from wheel speed sensors. In a case where a vehicle speed calculation is shifted from a first method to a second method, a vehicle speed displayed on a speedometer is gradually changed from the vehicle speed obtained by the first method to the vehicle speed obtained by the second method. This avoids abrupt change in the displayed vehicle speed causing the driver to feel discomfort.

Abstract: In a speedometer control system having wheel speed sensors as well as a vehicle speed sensor, both a PCM and a brake ECU are used to obtain vehicle speeds. Then, a signal corresponding to a vehicle speed is obtained basically from the PCM. However, if it is impossible to properly obtain a signal corresponding to a vehicle speed from the PCM, a signal corresponding to a vehicle speed is obtained from the brake ECU. Accordingly, even in the event that a signal corresponding to the vehicle speed is not obtained from the PCM, it is possible to obtain a signal corresponding to the vehicle speed from the brake ECU, and thus to display the vehicle speed on a speedometer.

Abstract: A brake hydraulic pressure control apparatus includes a pressure-increasing valve disposed between a master cylinder and a wheel cylinder; a pressure-reducing valve disposed between the wheel cylinder and a reservoir; and a hydraulic pump for pumping brake fluid from the reservoir (secondary circuit) so as to return the brake fluid to a primary circuit between the master cylinder and the pressure-increasing valve. Through control of these valves, brake hydraulic pressure within the wheel cylinder is controlled. In addition, the hydraulic pump is driven at least over a period in which the brake hydraulic pressure control is performed. When the vehicle is in a predetermined state which indicates that the driver does not have an intention of performing the brake operation, both the pressure-increasing valve and the pressure-reducing valve are opened over a predetermined period of time so as to establish communication between the primary circuit and the secondary circuit.

Abstract: Numbers of teeth of respective rotors are obtained once and stored in an EEPROM. Then, when an ignition switch is initially turned on, vehicle wheel speeds for the respective vehicle wheels are derived based on the information about the numbers of teeth stored in the EEPROM. Accordingly, it is possible to obtain the vehicle wheel speeds even during a calculation period while the number of teeth of each rotor is being calculated each time the ignition switch is turned on. Further, it also becomes possible to perform ABS control prior to when the vehicle wheel speed calculation is completed.

Abstract: In a speedometer control system having wheel speed sensors as well as a vehicle speed sensor, both a PCM and a brake ECU are used to obtain vehicle speeds. Then, a signal corresponding to a vehicle speed is obtained basically from the PCM. However, if it is impossible to properly obtain a signal corresponding to a vehicle speed from the PCM, a signal corresponding to a vehicle speed is obtained from the brake ECU. Accordingly, even in the event that a signal corresponding to the vehicle speed is not obtained from the PCM, it is possible to obtain a signal corresponding to the vehicle speed from the brake ECU, and thus to display the vehicle speed on a speedometer.

Abstract: Numbers of teeth of respective rotors are obtained once and stored in an EEPROM. Then, when an ignition switch is initially turned on, vehicle wheel speeds for the respective vehicle wheels are derived based on the information about the numbers of teeth stored in the EEPROM. Accordingly, it is possible to obtain the vehicle wheel speeds even during a calculation period while the number of teeth of each rotor is being calculated each time the ignition switch is turned on. Further, it also becomes possible to perform ABS control prior to when the vehicle wheel speed calculation is completed.

Abstract: A newly obtained wheel speed of a drive wheel is not used in a calculation for acceleration slip when a vehicle is stopped, for example, when the wheel speed of a rolling wheel is zero and an engine speed is high. A wheel speed calculated before a previous wheel speed is, for example, set as a current wheel speed. In this manner, even if the wheel speed of a driving wheel is due to the effect of racing noise, it is possible to limit erroneous determinations that indicate acceleration slip is being generated, based upon such a wheel speed. In addition, unnecessary execution of a traction control can also be curbed.

Abstract: A vehicle speed is obtained from detection signals obtained from wheel speed sensors. In a case where a vehicle speed calculation is shifted from a first method to a second method, a vehicle speed displayed on a speedometer is gradually changed from the vehicle speed obtained by the first method to the vehicle speed obtained by the second method. This avoids abrupt change in the displayed vehicle speed causing the driver to feel discomfort.

Abstract: A brake hydraulic pressure control apparatus includes a pressure-increasing valve disposed between a master cylinder and a wheel cylinder; a pressure-reducing valve disposed between the wheel cylinder and a reservoir; and a hydraulic pump for pumping brake fluid from the reservoir (secondary circuit) so as to return the brake fluid to a primary circuit between the master cylinder and the pressure-increasing valve. Through control of these valves, brake hydraulic pressure within the wheel cylinder is controlled. In addition, the hydraulic pump is driven at least over a period in which the brake hydraulic pressure control is performed. When the vehicle is in a predetermined state which indicates that the driver does not have an intention of performing the brake operation, both the pressure-increasing valve and the pressure-reducing valve are opened over a predetermined period of time so as to establish communication between the primary circuit and the secondary circuit.

Abstract: A motor trouble detection device detects trouble in a motor used in an anti-skid brake control system for returning the brake fluid to the reservoir tank. The trouble detection is based on the counter electromotive force generated by the motor which is turned off after driving for a predetermined period. The device includes a first detector for judging whether the counter electromotive force is smaller than a predetermined voltage and a second detector for judging whether the motor is in trouble based upon the first detector.

Abstract: A photovoltaic device includes a semi-continuous metal layer having an uneven surface, which is not uniform, formed on a substrate, a reflective continuous metal layer having a substantially uniform thickness formed to cover the semi-continuous metal layer, a semiconductor film for photoelectric conversion formed on the reflective continuous metal layer, and a transparent electrode formed on the semiconductor film.

Abstract: An amorphous semiconductor solar cell includes an i type layer which is an at least partially alloyed, substantially intrinsic semiconductor, an n type layer formed on one side of the i type layer, and a p type layer formed n the other side of the i type layer, and the i type layer has its energy bandgap varied in a thickness direction to have a bandgap larger than the bandgap of the p type layer in the vicinity of the interface with the p type layer.