ROTARY DIRECTION DETECTION DEVICE

• Main Authors: ISHIKAWA ICHIRO, ONE KENICHI, SEKI HIDEO
• Format: Patent
• Language: English
• Published: 30.04.1996
• Edition: 6
• Subjects: INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT; MEASURING; MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION,OR SHOCK; PHYSICS; TESTING

PURPOSE: To accurately detect the rotary direction of a target to be measured by additionally layer out a detection element in the middle of a pair of detection elements which are laid out so that they can be successively and magnetically connected to a detection member provided on the surface of a rotator. CONSTITUTION: A detection member II such as a permanent magnet is provided at the outer periphery of a rotator 10 and three Hall elements 13a-13c are fixed and laid out so that they can be connected to the detection member 11 successively in terms of time along the rotary trace of the member 11 opposing the detection member 11. The outputs of the Hall elements 13a, 13c, and 13b are read into a signal processing judging device 15 and a difference operation part 15A calculates the difference (A-B) of the output of the Hall elements 13a and 13b and a sign inversion detection part 15B detects that the sign of the difference (A-B) is inverted from plus to minus. A level judgment part 15C judges whether the level of an output C of the Hall element 13c is high or low when the sign is inverted. A rotary direction judgment part 15D outputs a signal ACB (P direction) or BCA (Q direction) indicating the rotary direction according to a predetermined reference.