Abstract: Disclosed is a SCARA robot having a robot body, a mount movable vertically of the robot body, a first arm having one end operatively connected to the mount such that the first arm may turningly move in a horizontal plane, a second arm having one end operatively connected to the opposite end of the first arm such that the second arm may turningly move in a horizontal plane, and an R shaft rotatably mounted on the free end of the second arm, wherein stepping motors 12, 22, 32 and 42 are provided to move the first and second arms, the R-shaft and the mount respectively, and encoders are provided to count the stepping pulses of the stepping motors. The counted pulses are feedbacked to CPU1 so that the CPU1 may correct errors when the errors are detected between the counted number of pulses and a required number of pulses. When the errors are detected, the stepping motors may be stopped and the errors may be indicated.

Abstract: Disclosed is a robot having multi-joint arms movable in a horizontal plane, which is mechanically compact as well as small sized and operated with high precision and a minimum output of drive sources, substantially comprising a robot body (1), a cylindrical mount (2) movable vertically of the robot body through a guide means (3) and a slider means (4), a vertical threaded shaft (6) rotatably journaled in the robot body and operatively connected to the cylindrical mount, the vertical threaded shaft being rotated by a first drive motor (5) to vertically move the cylindrical mount therealong, a first arm (9) having one end operatively connected to the cylindrical mount so as to be turningly moved in a horizontal plane by a second drive motor (12), a second arm (10) having one end operatively connected to the opposite end of the first arm so as to be turningly moved in a horizontal plane by a third drive motor (17), and a control R shaft (11) rotatably mounted on a free end of the second arm so as to be rotated b