JPS60263856A - Method and instrument for inspecting can sealing - Google Patents

Abstract

PURPOSE:To perform an inspection for can sealing of a body to be inspected automatically and efficiently by sounding the sealing of a can with its electrical deformation, by obtaining an electrical signal with its sound collection and by discriminating electrically. CONSTITUTION:A canned food 4 to be inspected is transferred by a belt conveyor 41. An inspection device A is provided on the canned food 4 thereof and a magnetic field is generated by impressing an exciting output from an exciting circuit 5 to a coil 1. A sound wave is generated by deforming at least one part of the sealed can by the magnetic field thereof. The sound wave thereof is collected with a sound collecting apparatus, for instance, a microphone 2. The microphone 2 thereof inputs its outputting electrical signal to a comparator 6 for comparison with the reference value and the inspection result is displayed 7. The inspection can be thus performed automatically with higher accuracy due to the sealing of can being inspected electrically by sounding the can by magnetic field.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention relates to a method for inspecting the seals of canned or bottled products, particularly for products in which at least a portion of the container contains a magnetic metal material such as iron or permalloy. and a sealed can inspection device.

BACKGROUND TECHNOLOGY Conventionally, as a method for determining the quality of sealed cans and bottled products, etc., after sealing a can, a part of the can or cap is struck with a hammer, and the pitch of this insect-repelling sound is detected by the auditory sense of the former person. An extremely artificial inspection method that requires a high degree of skill has been used to discriminate and determine pass/fail.

For this reason, the accuracy of the pass/fail discrimination was lacking, and the working efficiency was limited to about 100 discriminations per minute, resulting in poor workability.

OBJECT OF THE INVENTION The present invention was developed in view of the drawbacks of the conventional sealing inspection methods described above. It is an object of the present invention to provide a sealing inspection method and an apparatus therefor which have high discrimination accuracy and excellent workability by electrically discriminating to determine whether the sealing is good or not.

Summary of the Invention In order to achieve the above object, the present invention combines an electromagnet, a sound collection device, and a moving mechanism for the same to magnetically deform an object to generate sound, and collect the sound with a microphone or the like. This device obtains an electrical signal and electrically discriminates the signal to determine whether the test object is sealed properly.Its configuration is to apply a desired current, such as a sinusoidal or pulsed wave, to a coil to generate a magnetic field. The magnetic field deforms at least one part of the blockage of the test object, such as a canned or bottled product, to generate a sound wave, and a sound collecting device such as a microphone placed at an optimal position with respect to the blockage generates a sound wave. The sealing inspection device according to the present invention is characterized in that the sound waves are converted into electric signals and detected, and the sealing is inspected using the signals. A sound collecting means consisting of sound collecting equipment such as a microphone or a piezoelectric sensor that detects sound waves emitted by the blockage that is the test object;
The present invention is characterized by comprising a moving means for parking the magnetic field generating means and the sound collecting means at optimal positions for detecting the sound waves in accordance with the shapes and dimensions of various test objects.

Embodiment Hereinafter, an embodiment of the sealing inspection method and apparatus of the present invention will be described with reference to the drawings.

FIG. 1 is a cross-sectional view of a sealing inspection device showing essential parts of an embodiment of the present invention, with some parts omitted. The magnetic field generating means consists of a magnetic core 11 around which a coil 1 is wound, and a case 12 made of brass or plastic as an outer sheath. , a microphone 2 is disposed inside the magnetic core 11 and serves as a sound collecting means.
is screwed onto the shaft 31 via the mounting bracket 21, and further the shaft 31
A part of the microphone 2 is rotatably supported on a structural member 32 of a movable arm 3, and a rotation knob 33 is fitted to the end of the shaft so that the microphone 2 can be moved up and down. Depending on the shape and dimensions of the test object, such as packed or bottled products, move the arm 3 back and forth, up and down, and turn the knob 33 to park the microphone 2 at the optimal position relative to the test object. 1, a desired excitation current having a predetermined duration of several kHz to several tens of kHz is applied to generate a magnetic field, the magnetic field deforms a part of the object to generate sound, and the object is parked at the optimum position. An electrical signal is obtained by a sound collecting microphone 2 that stops.

FIG. 2 shows a schematic diagram of another embodiment of an automatic sealing inspection device in which the present invention is combined with a test object conveyance device such as a belt conveyor.

The test object 4 is placed on a conveying device 41 such as a belt conveyor, and is automatically transported directly below the coil 1 and the microphone 2, and the coil 1 magnetically deforms the test object 4 and generates a sound wave. Sound is collected by microphone 2. 5 is an excitation circuit that excites the coil 1; 6 is a comparison device that includes a comparator that processes the electric signal output from the microphone as desired and compares it with a reference signal; and 7 is a display device that displays the quality of the test results. , 8 is a control device including a computer, etc., which controls each of the above-mentioned signal processing circuits and devices at a desired timing. According to this embodiment, the electric signal collected by the microphone and output as described above is transmitted to the scolding device 6.
The filter circuits, differential circuits, discrimination circuits, etc. that make up the reference signal are compared with the reference signal waveform, strength, phase, etc. by performing resonance and beat processing as necessary, and the pass/fail signal is displayed on the display device 7. The inspection results of sealed cans can be displayed at outputs 1 and up.

In the above embodiments, a microphone is used as a sound collecting device, but a piezoelectric sensor or the like may also be used.Furthermore, a resonance box, an acoustic tube, etc. may be appropriately arranged in the sound collecting device, and a display device may also be provided with a resonance box, an acoustic tube, etc. Modifications such as adding an exclusion mechanism to remove defective products for automatic sorting can be easily made within the technical scope of the present invention.

Effects of the Invention According to the present invention, as described above, the sound collecting device is moved and parked at the optimum position relative to the test object, and the test object is magnetically deformed to produce sound, and the sound is generated by the sound collecting device. The quality of the seal can be tested by electrically processing the electrical signals generated, and the following effects can be achieved.

(1) It is possible to automatically conduct a sealing inspection of a test object.

(2) Inspection processing capacity will dramatically increase to several thousand tests per minute.

(3) The accuracy of pass/fail determination becomes high, eliminating inspection errors.

(4) It is possible to provide an easy-to-use inspection method and apparatus that can be widely applied to various types of irregularly shaped specimens.

[Brief explanation of drawings]

FIG. 1 is a partially omitted cross-sectional view showing essential parts of an embodiment of the present invention, and FIG. 2 is a schematic diagram of an automatic seal inspection device to which the present invention is applied. 1... Coil 2... Microphone 3... Arm 4... Test object 5... Excitation circuit 6... Comparison device complete... Display device 8... Control device Figure 1 1 11

Claims (4)

[Claims] (1) A desired electric current is applied to generate a magnetic field, and the magnetic field deforms at least a portion of the sealing can, which is the object to be tested, thereby generating a sound wave and positioning it at an optimal position with respect to the sealing can. A sealed can inspection method, characterized in that the sound waves are converted into electrical signals and detected by a sound collecting device provided, and the signals are used to inspect the quality of the sealed can. (2) Can inspection characterized by having a magnetic field generating means, a sound collecting means for detecting sound waves emitted by a sealed can as an object to be inspected, and a moving means for parking the sound collecting means at an optimal position. Device. (3) The sealed can inspection device according to claim 2, wherein the magnetic field generating means comprises a coil and a magnetic core around which the coil is wound. (4) The seal inspection device according to claim 2, wherein the sound collecting means comprises a magnetic core having a small-diameter opening on at least one surface, and a microphone that is inside the magnetic core and is movable inside the magnetic core. .