Wrist Assembly of Parallel Robot Using Differential Gears

Abstract

The present invention relates to a parallel robot having its wrist structure with three degrees of freedom using differential gears. According to the present invention, a wrist assembly of the parallel robot using the differential gears, joint-connecting a three group link part comprises: a driving link and a manual link between a base plate and an actuator in parallel; and coupling a wrist assembly with three degrees of freedom to control the posture of an end effector to the actuator. The present invention installs a first to a third input shaft in the actuator and connects the input shafts to three driving shafts which transmits a driving force from three motors, respectively. The wrist assembly comprises: a first rotor connected to the first input shaft rotating around the first rotational axis vertical to a plane of the actuator; a second-1 rotor connected to the second input shaft rotating around the second rotational axis meeting at a right angle with the first rotational axis; a second-2 rotor connected to the third input shaft, rotating around the second rotational axis, and rotating while forming a differential gear device with the second-1 rotor; and a third rotor rotating by differential driving of the second-1 and the second-2 rotor around the third rotational shaft meeting at right angles with the second rotational shaft and installing the end effector.

Description

technical field [0001] The present invention relates to parallel robots. Specifically, a parallel robot with three degrees of freedom in the wrist structure of a parallel robot using differential gears. Background technique [0002] Parallel robots are mainly used for high-speed transfer of light-weight products or accessories. According to the number of joints, they are called delta robots or quattro robots. [0003] A general delta-type parallel robot includes a base part, a movable part, first to third link parts connecting the base part and the movable part, and a wrist part is also provided on the movable part. [0004] Such a delta-type parallel robot is disclosed in Japanese Patent No. 4659098. [0005] In the parallel robot disclosed in Japanese Patent No. 4659098, three groups of link mechanisms composed of drive links and manual links are used to connect the joints in parallel between the base part and the movable part. A parallel link robot with a three-degree-...

AI Technical Summary

Problems solved by technology

[0008] However, the wrist structure of the parallel robot disclosed in Japanese Patent No. 4659098 realizes three degrees of freedom based on three axes, but according to Geometric optimization of serial chain manipulator structures for working volume and dexterity, R Vijaykumar, KJ Waldron, MJ Tsai , 1986, International Journal of Robotic Research, although the three axes form 90 degrees to each other, they do not meet at one point. Therefore, it is impossible to satisfy the theoretically optimized wrist mechanism.

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