Multi-joint robot capable of motion control

A multi-joint robot for taking out a molded object, comprising:

• a controller configured to control driving of joints of the multi-joint robot;
• a marker provided on each of the joints of the multi-joint robot;
• a camera part connected to the controller and configured to photograph movement of the marker and transmit movement information of the multi-joint robot according to the movement of the marker to the controller;
• and
• an overrun detector provided on at least one of the joints of the multi-joint robot and configured to detect an overrun operation exceeding an operation range of joint movement and transmit a warning signal about the overrun operation to the controller,
• wherein the controller controls a supply of power for the joint movement to be cut when the warning signal is received,
• the overrun detector detects an overrun operation by measuring a degree of deformation of a joint axis relative to a force applied to the joint axis,
• the overrun detector comprises:
• an optical path formed from one point on an outer circumferential surface of the joint axis to another point on the outer circumferential surface while passing through the joint axis;
• a light incidence part configured to allow detection light to be incident toward the one point from an outside of the joint axis;
• and
• a light receiver positioned opposite to the light incidence part with respect to the joint axis and configured to receive the detection light coming from an other point while passing through the optical path,
• the joint axis is fixed to cause the optical path to be misaligned by a certain angle with respect to the light incidence part and the light receiver,
• when a turning force is applied to the joint axis through a driving gear coupled to one end of the joint axis, the joint axis transmits the turning force to a body part to which the joint axis is coupled through a fixing part coupled to an other end of the joint axis,
• the other end of the joint axis is provided with a fixing groove into which the fixing part is inserted,
• the fixing part is inserted into the fixing groove, and the turning force is applied to the fixing part from the joint axis,
• the fixing part is separated from the fixing groove when the detection light reaches the light receiver,
• the light incidence part and the light receiver are formed between the driving gear and the fixing part,
• the light receiver transmits the warning signal to the controller when an angle of the optical path matches the light incidence part and the light receiver due to deformation of the joint axis and thus the detection light reaches the light receiver,
• the fixing part is provided in a form of a bar in a first direction perpendicular to an outer circumferential surface of the joint axis,
• the fixing part is moved to cause one end thereof to be inserted into or separated from the fixing groove,
• an other end of the fixing part is provided with a protrusion,
• a first spring for pressing the protrusion toward the other end of the fixing part is coupled to the protrusion,
• the other end of the fixing part is provided with a blocking bar for blocking movement of the fixing part, and
• the blocking bar is moved to cancel the blocking of the movement of the fixing part when the detection light reaches the light receiver.