Thread tightening device based on visual positioning and control method

Abstract

The invention discloses a thread tightening device based on visual positioning and a control method. The device comprises a robot, a control system, a feeding mechanism, a visual measurement module and a tightening tool, wherein the control system is in communication connection with the robot and the tightening tool; the feeding mechanism comprises a rack, a conveying belt, a material disc, material baffles, a blocking air cylinder, a clamping air cylinder and a photoelectric sensor, the conveying belt is installed on the rack, the material disc is placed on the conveying belt, the material baffles are installed on the two sides of the conveying belt, the blocking air cylinder and the clamping air cylinder are installed on the same side of the material baffles, and the photoelectric sensor is installed on the opposite side of the blocking air cylinder; and the vision measurement module is installed on the rack, the tightening tool is installed on a flange of a sixth shaft of the robot, and the vision measurement module is located above a tightening operation area. According to the thread tightening device based on visual positioning and the control method, the positions of a plurality of bolts can be rapidly positioned, the tightening torque is controlled through programming, the thread tightening control precision is improved, and the expected tightening effect of thread connection can be achieved.

Description

technical field [0001] The invention relates to the technical field of thread tightening assembly, in particular to a visual positioning-based thread tightening device and a control method. Background technique [0002] At present, most manufacturers still use hand-held electric or pneumatic tools to assemble threaded fasteners, or use special locking screw machines to realize semi-automatic screw tightening functions, and a small number of them use fixtures + robots to fasten threads Assembling the parts, that is, the preliminary positioning of the workpiece to be assembled by the tooling fixture, and then using the robot equipped with tightening tools to control the trajectory and positioning through teaching and learning, and complete the screw assembly and tightening process, such as Xiao Hai's "Robot Bolt Tightening" In the article "Application of Technology in Engine Assembly", first insert the guide pin in the jacking mechanism into the corresponding positioning hole ...

AI Technical Summary

Problems solved by technology

[0003] With the continuous increase of labor costs, the production cost of thread assembly of fasteners using hand-held tools is high, and the tightening accuracy is greatly affected by human factors; the use of special locking screw machine equipment generally cannot flexibly adjust the tightening position, nor can it be adjusted according to It is necessary to flexibly set or change the tightening torque to obtain higher tightening control precision; the use of robot teaching method to thread assembly of fasteners has the disadvantages of complex design of fixtures and high requirements for repeatable positioning accuracy of robots, and adjustment flexibility Poor; The use of SCARA robot visual positioning guidance for thread tightening is only allowed to carry small light-weight tightening tools, and the tightening operations should generally be distributed on a plane, which cannot meet the requirements of multi-directional or attitude thread assembly

[0004] At the same time, during the tightening process of the robot, it is generally equipped with a tightening tool commonly used on the market - an electric screwdriver. Generally, it can only set a certain upper limit torque threshold, and stop rotating when the torque threshold is reached. On the one hand, the torque control accuracy is very low. On the other hand, it is not possible to set different tightening torque values ​​for different threaded fasteners, and plan a more appropriate tightening process to obtain the best assembly effect

At the same time, such tightening tools generally do not have a tightening process data feedback function, and cannot directly judge and warn of abnormalities in the tightening process, and cannot further trace and process the tightening data.

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