Patent ID: 6784383
Filing Date: 2004-08-31
Classification: H01H

Abstract:
A rotary encoder outputting rectangular wave signals comprisinga contact-point board having a conductive signal pattern and a common pattern; and a slider supported to be revolvable with respect to said contact-point board, which slider having a plurality of movable contact points disposed on a circle of a certain radius from a revolution center at an angular interval six times as large as an output pitch of the rectangular wave signal; wherein said signal pattern consists of three fixed contact points, each having two conductive layers of radial shape with the same width, electrically connected to each other, disposed along sliding circle of said movable contact points at an angular pitch three times as large as the output pitch of the rectangular wave signal; angular pitch of said three fixed contact points is different from one of angular interval of said movable contact points, and a multiple of the angular interval of said movable contact points, by one of the output pitch of the rectangular wave signal, and twice of the output pitch of the rectangular wave signal, and larger than any one angular width of said three fixed contact points; and said common pattern is disposed insulated from said signal pattern on said contact-point board along sliding circle of said movable contact points, so that, at the time when either one of said movable contact points of said slider is having contact with either one of said three fixed contact points, it makes contact with remaining one of said movable contact points.