Rotational angle measuring apparatus

A rotational angle measuring apparatus comprising:

• a rotating member rotated in cooperation with a rotating body constituting an object of measurement;
• a plurality of angle sensors attached to the rotating member for detecting a periodic angular position thereof;
• an involatile data storing portion for storing a reference position of the angle sensor;
• and
• operating and controlling means for subjecting the reference position and detected data from the respective angle sensors to an operational processing to thereby calculate a frequency of the rotating body constituting the object of measurement and calculating absolute rotational angles of the rotating body constituting the object of measurement and constituting an average value thereof as a measured output;
• wherein the operating and controlling means switches a mode thereof from a normal operation mode for continuously reading the detected data from the angle sensors and executing the operational processing to a low current consumption mode for reading the detected data from the angle sensors and executing the operational processing by an intermittent operation by receiving a pause signal from outside.

A rotational angle measuring apparatus comprising:

• a rotating member rotated in cooperation with a rotating body constituting an object of measurement;
• an angle sensor attached to the rotating member for detecting a periodic angular portion thereof;
• an involatile data storing portion for storing a reference position of the angle sensor;
• and
• operating and controlling means for subjecting the reference position and detected data from the angle sensor to an operational processing to thereby calculate a frequency of the rotating body constituting the object of measurement and calculating an absolute rotational angle of the rotating body constituting the object of measurement to thereby constitute a measured output;
• wherein the operating and controlling means switches a mode thereof from a normal operation mode for continuously reading the detected data from the angle sensor and executing the operational processing to a low current consumption mode for executing the operational processing by reading the detected data from the angle sensor by an intermittent operation by receiving a pause signal from outside;
• the rotating body constituting the object of measurement is a steering shaft, the measured output is a steering angle and the pause signal is a signal for making an ignition switch off;
• and
• the operating and controlling means sets a frequency to null by an angular position when the vehicle is determined to be brought into a linearly advancing state based on a signal from a sensor for detecting a behavior of the vehicle when a power source has been removed and thereafter connected again.

A rotational angle measuring apparatus comprising:

• a rotating member rotated in cooperation with a rotating body constituting an object of measurement;
• a plurality of angle sensors attached to the rotating member for detecting a periodic angular position thereof;
• an involatile data storing portion for storing a reference position of the angle sensor;
• and
• operating and controlling means for subjecting the reference position and detected data from the respective angle sensors to an operational processing to thereby calculate a frequency of the rotating body constituting the object of measurement and calculating absolute rotational angles of the rotating body constituting the object of measurement and constituting an average value thereof as a measured output;
• wherein the operating and controlling means switches a mode thereof from a normal operation mode for continuously reading the detected data from the angle sensors and executing the operational processing to a low current consumption mode for reading the detected data from the angle sensors and executing the operational processing by an intermittent operation by receiving a pause signal from outside;
• the rotating body constituting the object of measurement is a steering shaft, the measured output is a steering angle and the pause signal is a signal for making an ignition switch off;
• and
• the operating and controlling means sets a frequency to null by an angular position when the vehicle is determined to be brought into a linearly advancing state based on a signal from a sensor for detecting a behavior of the vehicle when a power source has been removed and thereafter connected again.

A rotational angle measuring apparatus comprising:

• a rotating member rotated in cooperation with a rotating body constituting an object of measurement;
• a plurality of angle sensors attached to the rotating member for detecting a periodic angular position thereof;
• an involatile data storing portion for storing a reference position of the angle sensor;
• and
• operating and controlling means for subjecting the reference position and detected data from the respective angle sensors to an operational processing to thereby calculate a frequency of the rotating body constituting the object of measurement and calculating absolute rotational angles of the rotating body constituting the object of measurement and constituting an average value thereof as a measured output;
• wherein the operating and controlling means switches a mode thereof from a normal operation mode for continuously reading the detected data from the angle sensors and executing the operational processing to a low current consumption mode for reading the detected data from the angle sensors and executing the operational processing by an intermittent operation by receiving a pause signal from outside;
• when a difference between the absolute rotational angles based on the rotational angles detected by the respective angle sensors is larger than a predetermined value, the operating and controlling means determines that an abnormality is caused;
• the rotating body constituting the object of measurement is a steering shaft, the measured output is a steering angle and the pause signal is a signal for making an ignition switch off;
• and
• the operating and controlling means sets a frequency to null by an angular position when the vehicle is determined to be brought into a linearly advancing state based on a signal from a sensor for detecting a behavior of the vehicle when a power source has been removed and thereafter connected again.

A rotational angle measuring apparatus comprising:

• a rotating member rotated in cooperation with a rotating body constituting an object of measurement;
• a plurality of angle sensors attached to the rotating member for detecting a periodic angular position thereof;
• an involatile data storing portion for storing a reference position of the angle sensor;
• and
• operating and controlling means for subjecting the reference position and detected data from the respective angle sensors to an operational processing to thereby calculate a frequency of the rotating body constituting the object of measurement and calculating absolute rotational angles of the rotating body constituting the object of measurement and constituting an average value thereof as a measured output;
• wherein the operating and controlling means switches a mode thereof from a normal operation mode for continuously reading the detected data from the angle sensors and executing the operational processing to a low current consumption mode for reading the detected data from the angle sensors and executing the operational processing by an intermittent operation by receiving a pause signal from outside;
• when there is present an absolute rotational angle in which a difference between said absolute rotational angle and an average value of the absolute rotational angles based on the rotational angles detected by the respective angle sensors is larger than a predetermined value, the measured output is constituted by an average value of the other absolute rotational angles excluding said absolute rotational angle;
• the rotating body constituting the object of measurement is a steering shaft, the measured output is a steering angle and the pause signal is a signal for making an ignition switch off;
• and
• the operating and controlling means sets a frequency to null by an angular position when the vehicle is determined to be brought into a linearly advancing state based on a signal from a sensor for detecting a behavior of the vehicle when a power source has been removed and thereafter connected again.