JPS58170416A - Egg distinguishing apparatus - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an egg identification device, and more particularly to an identification device for identifying the presence or absence of cracks in eggshells.

In general, for example, chicken eggs have no commercial value at all even if their shells have tiny cracks that are hard to discern visually, and it is necessary to sort out and remove the defects during the packaging stage.

Until now, the only way to detect cracks in chicken egg shells was to rely on visual inspection. Currently, the most widely used method is to shine a light on the egg from below and look at it to see if there are any cracks in the egg shell. This visual method has the following drawbacks.

(b) Inspectors often complain of eye fatigue, and countermeasures are required from an occupational health perspective.

(b) It is difficult to detect cracks on the underside of the egg.

(c) The egg feeding section, egg washing section, and weight sorting section of the egg packing machine are
All other departments, such as the size sorting department and box packing department, are currently automated, but the egg checking department relies on human eyes, so the flow of eggs is stagnant here. Automation of the task of identifying the presence or absence of cracks in eggs has long been desired in order to fully automate egg packaging machines from start to finish, but this has not been achieved until now.

By the way, the inventor has discovered the so-called acoustic emission (AE) phenomenon, in which when a solid under stress deforms or breaks, strain energy is released and elastic waves (in the audible and ultrasonic ranges) are generated. We have developed a device that can reliably identify cracked eggs by combining the presence of a notch with the phenomenon that stress concentrates in the notch when stress is applied.

That is, the present invention was made in order to solve the above-mentioned drawbacks and to meet the demand for automating the entire process of egg packaging machines. , when a small force is applied to a cracked egg, stress concentration occurs at both ends of the crack, and when the crack grows, it generates AE. Taking advantage of this phenomenon, the egg is pressurized and the cracks (or Stress is concentrated on the cracks or holes (hereinafter referred to as cracks) to encourage crack growth, and the elastic waves generated in the shell at this time are converted into electrical signals by a detector to easily detect the presence or absence of cracks in the egg shell. It is an object of the present invention to provide an egg identification device that can reliably identify eggs.

Therefore, in order to achieve this object, the present invention includes at least a pressing means that presses the egg shell, and a detector that detects the elastic waves generated in the egg shell and converts it into an electric signal. Features.

The present invention will be explained below with reference to an illustrated embodiment.

As shown in FIGS. 1 and 2, the pedestal 1 is shaped to hold a shell 2a of an intact fish egg 2 with no cracks or a shell 3a of a defective egg 3 with a crack H. A pressing means 4 is provided at an upper position. A detector 5 made of a piezoelectric material (for example, lead zirconate titanate piezoelectric ceramic) is attached to this pressing means. This detector 5 has a resonant frequency characteristic capable of detecting an acoustic pulse accompanying an elastic wave generated in the shell 3a of the defective egg 3, and this pressing surface 5a is formed in a plane, and the pressing means 4 Accordingly, the pressing surface 5a is mechanically pressed against the shell 2a of the intact fish roe 2 or the shell 3a of the defective egg 3 on the mount 1 with a small force that does not break the egg.

The detector 5 is connected to an oscilloscope 8 via a preamplifier 6 and a discriminator 7, which serve as a signal processing section for the detection signal output from the detector 5.

The above-mentioned pedestal 1 is installed, for example, in the middle of the conveying section between the egg feeding section and the washing section of the above-mentioned egg packaging machine, and eggs are automatically fed to the pedestal 1 from the egg feeding section. There is.

Next, the operation of the above configuration will be explained.

First, the case where intact fish eggs 2 are fed to the mount 1 will be explained with reference to FIG. When intact fish eggs 2 are fed to the pedestal 1, the pressing means 4 presses the suppressing surface 5a of the detector 5 against the shell 2a.
Press down with just enough force to avoid breaking the egg. However,
Since there are no cracks in the shell 2a, no elastic waves, that is, acoustic pulses are generated, and only the noise N appears on the screen of the oscilloscope 8.

Next, defective eggs 3 are fed to cradle 1, and ? The case will be explained with reference to FIG. When the defective egg 3 is fed to the cradle 1, the pressing means 4 presses the pressing surface 5IL against the shell 3a with a small force that does not break the egg, as in the case described above. There is a crack H in the shell 3a that is difficult to visually identify, and by pressing the pressing surface 5a, stress is concentrated on the crack H and the growth of the crack H is promoted. At this time, the shell 3a
An acoustic pulse S is generated. This acoustic pulse S is converted into an electrical signal by a detector 5, and the electrical signal is converted into a preamplifier 6.
The signal is amplified by the discriminator, and after being amplified, detected, and noise removed by the discriminator, it appears on the screen of the oscilloscope 8 as an AE waveform W.

By the way, the threshold value of the AE waveform is set in advance to be slightly higher than the level of the noise N appearing on the oscilloscope 8 in the case of the intact fish roe 2, as shown in FIG. If the defective egg 3 is exceeded, it can be determined that the defective egg 3 has a crack, and the defective egg 3 is selected and removed.

In this way, the presence or absence of cracks in eggs can be easily identified mechanically by pressing the detector 5 against the shell, and the above device was actually used in experiments to distinguish between defective eggs and intact fish eggs. When I did this, I was able to identify it with a probability of 99.9%.

Incidentally, even if the preamplifier 6 and discriminator 7 as the signal processing circuits described above are omitted, the presence or absence of cracks in the egg can be determined. Further, the contact surface of the detector may be a flat surface or a curved surface. And to ensure detection of elastic waves, silicone grease may be applied to the contact between the egg and the detector. Furthermore, the number of detectors is not limited to one; for example, the detectors may be placed above and below the egg, or on the left and right sides, and the detector may be pressed against the egg by hand or by mechanical force such as a spring. It is also possible to oscillate while pressing.

Further, the pressing device is not limited to the detector, and other devices may be used to press at one location or several locations, and the generated elastic waves may be converted into electrical signals by the detector.

The electric/electrical signal from the detector can be checked visually by connecting it to the screen of an oscilloscope or a light as mentioned above, or by connecting it to a speaker and checking it audibly. It's okay.

Next, a second embodiment of the invention will be described with reference to FIG. Note that the same reference numerals are given to the parts corresponding to those in the first embodiment, and the explanation thereof will be omitted.

What is shown in FIG. 4 is a system in which the electric signal from the detector 15 is processed by a computer so that cracked eggs can be removed from the transport section. has the same configuration as the first embodiment, and the discriminator is connected to a computer 10 via an interface 9, and an identification signal output from the computer 10 is input to the gantry operating means 11. It is now possible to do so.

First, when the detector 15 presses the intact fish roe 2 on the stand 1, a noise N with a lower level than the threshold value is inputted to the computer IO via the interface 9, and the computer 10 outputs the noise N for intact fish roe identification. Based on the signal
Frame operating means 1 operates the pedestal 1 to send the intact fish roe 2 to a transport section (not shown) that leads to the next process.

Also, when the detector 15 presses the defective egg 3 on the pedestal l,
An electrical signal with a higher level than the threshold value is input to the computer 10 in the same way as described above, and the gantry operating means 11 operates the gantry 1 based on the defective egg identification signal output from the computer 10 to identify the defective egg 3. is sent to the discharge section. By pressing the eggs fed onto the cradle 1 in this way with the detector 15, the presence or absence of cracks in the egg shell can be immediately identified and the eggs can be sorted into defective and intact eggs. In addition, whereas conventional work on the side requires manpower, this device eliminates the need for work on the side at all, making it possible to achieve full automation of the egg packaging machine, which has been strongly desired for a long time.

As explained above, according to the present invention, the configuration includes at least a pressing means for pressing the egg shell and a detector for detecting elastic waves generated in the egg shell and converting them into electrical signals. Therefore, it is possible to easily and reliably identify the presence or absence of cracks in egg shells, which has the effect of automating the entire process of the egg packaging machine.

[Brief explanation of the drawing]

1 and 2 show a first embodiment of the egg identification device according to the present invention.
The figure is an explanatory diagram showing the state of identifying defective eggs and performing I/λ.
The figure is a graph showing an AE waveform that detects cracks in the shell of a defective egg and its threshold value, and FIG. 4 is an explanatory diagram showing a second embodiment of the egg identification device according to the present invention. l... mount, 2... flawless eggs, 3... defective eggs, 4
...pressing means, 5...detector. Patent applicant Masami Noguchi Agent Patent attorney Norimitsu Nishimura Figure 1 Figure 211 W Figure 3 Figure 4

Claims (1)

[Claims] An egg identification device comprising at least a pressing means for pressing an egg shell, and a detector for detecting an elastic wave generated in the egg shell and converting it into an electric signal.