초록 ▼

A blind rivet set verification system for setting a blind rivet assessing the acceptability of the rivet set. The system includes a remote intensified rivet setting tool and computer hardware and software. The tool comprises a displacement transducer that produces a displacement signal and a pressur

A blind rivet set verification system for setting a blind rivet assessing the acceptability of the rivet set. The system includes a remote intensified rivet setting tool and computer hardware and software. The tool comprises a displacement transducer that produces a displacement signal and a pressure transducer that produces a pressure signal. The transducers are connected to the computer which receives the distinct signals. These signals are interpreted to plot a displacement-versus pressure waveform and to determine the velocity of the movement of an air piston that responds to the rivet set by hydraulic pressure. Using the combined date of the velocity waveform and the displacement-versus pressure waveform, the breakload is identified and compared against predetermined ideal data to assess the acceptability of the set. The displacement reading at break is corrected for jaw slippage and offset of the air piston.

대표청구항 ▼

A system for setting a blind rivet and evaluating the acceptability of the set, said rivet being of the type having a frangible tubular body and an elongated mandrel that includes an enlarged head and a stem extending rearwardly of the head and through said frangible tubular body, said system compri

A system for setting a blind rivet and evaluating the acceptability of the set, said rivet being of the type having a frangible tubular body and an elongated mandrel that includes an enlarged head and a stem extending rearwardly of the head and through said frangible tubular body, said system comprising: a hydraulically operated blind rivet setting tool, said tool including a rivet engaging assembly for engaging said stem of said mandrel and an axially movable piston assembly operatively coupled to said rivet engaging assembly for driving said mandrel in response to the application of pressurized hydraulic fluid to said piston assembly; a first transducer for monitoring the pressure of the hydraulic fluid applied to said, piston assembly during a rivet setting process and producing pressure output signals related thereto; a second transducer operatively associated with said tool for producing displacement output signals related to the movement of said piston assembly in the axial direction during the rivet setting process; and a control circuit, said control circuit having circuitry to: (a) receive a series of said pressure output signals and a series of said displacement output signals during the rivet setting process; (b) determine from said series of displacement output signals the velocity of said piston assembly during the rivet setting process; (c) identify the occurrence during the rivet setting process of the highest value of velocity; (d) use the occurrence of the highest value of velocity to identify the mandrel breakpoint; and (e) compare a breakpoint load value determined from the value of the pressure output signal at the mandrel breakpoint with a predetermined desired value.