METHOD OF INSPECTING PLASTIC MOLDED PRODUCT FOR DEFECT

• Main Authors: NAKAYAMA TAKAO, YAMAMOTO TAKEYA
• Format: Patent
• Language: English
• Published: 21.03.2000
• Edition: 7
• Subjects: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIRCHEMICAL OR PHYSICAL PROPERTIES; MEASUREMENT OF MECHANICAL VIBRATIONS OR ULTRASONIC, SONIC ORINFRASONIC WAVES; MEASURING; PHYSICS; TESTING; TESTING STATIC OR DYNAMIC BALANCE OF MACHINES ORSTRUCTURES; TESTING STRUCTURES OR APPARATUS NOT OTHERWISE PROVIDED FOR

PROBLEM TO BE SOLVED: To inspect all of a large number of molded products individually by a simple method by obtaining vibration characteristic information of each of a reference product and a tested product and comparing a difference between the vibration characteristic information of both of them. SOLUTION: For instance, a plastic molded product 1, whose first plastic and second plastic members 2, 3 are stuck to each with an adhesive or the like in a connection part 4, is inspected for defect while mounted on a vibration oscillating pin 5 and a vibration receiving pin 6a. According to an instruction from a computer 11, a vibration transmitting element 7 is vibrated with a driving frequency varied continuously, a vibration waveform received by a vibration receiving element 8a is analyzed, and a relationship between the frequency and an amplitude is held as data, while it is displayed in the form of a graph, for example. Frequency data and the like in a resonance state on a reference plastic molded product and the tested plastic molded product are compared mutually in a computer 11 or as a screen display 15, and it is determined whether the product is good or not on the basis of a dimension of a shift in a resonance frequency.