JPH03221891A - Device for detecting non-metallic foreign matter in kneading product - Google Patents

Abstract

PURPOSE:To simply and highly sensitively detect the mixing of a non-metallic foreign matter by allowing a frequency-modulated high frequency current to flow into a subject held between electrodes and measuring the frequency characteristics of voltage generated between the electrodes. CONSTITUTION:A high frequency current power supply 4 allows a constant high frequency current whose frequency is modulated so that a prescribed frequency band is swept to flow into a subject 1 such as a fish paste and cosmetics arranged between the electrodes 3, 3'. A measuring circuit 5 samples a voltage obtained by detecting and rectifying a voltage Vc generated between both the electrodes 3, 3' due to the flow of the high frequency current Ic into the subject 1 and a modulation signal Vs inputted from the power supply 4 based on a sampling pulse Ts applied from an arithmetic circuit 6 with a fixed time interval, executes the A/D conversion of the sampled signals, outputs the digital signals Vq, Vf to an arithmetic circuit 6, and successively stores the digital signals in a storage circuit. The arithmetic circuit 6 finds out the value of Q from resonance frequency fo and the impedance of the subject 1 indicated before and after the frequency.

Description

[Detailed description of the invention] [Technical field to which the invention pertains] Conventionally, detection of non-metallic foreign substances contained in a dough product has been carried out by human visual inspection, but since non-metallic foreign substances inside the product cannot be visually observed, I often missed it. The present invention relates to a device for detecting nonmetallic foreign matter in a dough product that can be completely automated regardless of whether the nonmetallic foreign matter is detected on the surface or inside of the product.

[Prior Art and Problems with the Invention] Conventionally, there are several types of foreign object detectors for detecting foreign objects in dough products. A typical example of these foreign object detectors is a metal detection and removal device. This metal detection and removal device detects and removes metal foreign substances mixed into raw materials for foods, medicines, and other products, and has a long history and is widely used. However, there is a problem in that the foreign substances that can be detected are limited to metals, and non-metals cannot be detected.

In addition, foreign object detectors using TV cameras are used to detect foreign objects attached to packaging materials and containers such as films, bottles, cans, and paper, but they can only detect foreign objects attached to the surface of the paste product. It could not be used to detect foreign objects.

In addition, an X-ray foreign object detection device is used that can detect foreign objects, not only metals, regardless of whether they are inside the surface or inside the surface. This device utilizes the fact that X-rays are proportional to their density and exhibit throat absorption characteristics, and the sensitivity is determined by the difference in density between the food being inspected and the foreign matter. Therefore, it is only possible to detect objects with high density and hardness, such as glass or metal, and it is impossible to detect foreign objects such as hair, plastic, vinyl, or cardboard.

Furthermore, attempts have been made to detect foreign objects using ultrasonic waves, but problems similar to those described above have arisen.

In order to solve the above problems, the present invention aims to improve the surface of the product,
The object of the present invention is to provide a device for detecting non-metallic foreign matter in a dough product that can detect foreign matter regardless of the inside, and also to provide a device for detecting foreign matter in a dough product that has a measurement speed that can be sufficiently applied in the manufacturing process.

Means for Solving Problem E] Therefore, the first aspect of the present invention is to ``resolve foreign matter contained in a dough product by multidimensionally using parameters that electromagnetically express the properties of the material at a frequency near the resonance frequency of the paste product. The second one is "a device for detecting non-metallic foreign matter in a dough product, which is characterized by automatically detecting foreign matter in a dough product by combining the two.""A device for detecting non-metallic foreign matter in a pastry product, which is characterized by automatically detecting non-metallic foreign matter in a pastry product."

[Principle] The principle of the device for detecting non-metallic foreign matter in a dough product of the present invention is that when a foreign matter is mixed into a dough product, the electromagnetic properties of the dough product change. Basic electromagnetic parameters expressing the properties of materials include dielectric constant (ε), electrical conductivity (σ), magnetic permeability, Q value, and resonance frequency. Detection of foreign matter based on changes in dielectric constant has been devised for some time, but since the volume of foreign matter mixed into a dough is extremely small compared to the volume of the dough5, it is difficult to detect foreign matter based on changes in dielectric constant. It doesn't show up. Furthermore, since air is involved in the manufacturing process of dough products, the dielectric constant varies, making it difficult to detect foreign substances. Similar considerations can be made for the detection of foreign substances due to changes in conductivity, etc.

Therefore, in the present invention, the first aspect of the present invention is to automatically detect foreign substances contained in a dough product by combining parameters that electromagnetically express the properties of the material at a frequency near the resonance frequency of the dough product in a multidimensional manner. We have devised a device for detecting non-metallic foreign substances in dough products, which is characterized by the following: Dielectric materials have unique frequency characteristics with respect to parameters that electromagnetically express the properties of materials, and dough products similarly have unique frequency characteristics. At frequencies near the resonance frequency, the rate of change in parameters that electromagnetically express the properties of substances between products that do not contain foreign substances and products that contain foreign substances becomes large. Therefore, parameters that electromagnetically express the properties of materials, specifically permittivity (ε), electrical conductivity (σ), magnetic permeability, Q value, etc., are combined into six multidimensional coordinates, and resonance occurs within this multidimensional coordinate. Draw a number of measurements taken at frequencies around the frequency. Then, the measured value will fall within a certain range. However, measured values that include foreign matter fall outside of a certain range. Foreign matter can be detected by finding measured values outside this range through numerical processing. As a specific example, FIG. 1 shows an example in which dielectric constant (ε) and Q value are two-dimensionally combined. Products that do not contain foreign substances (・) fall within a certain range, but products that contain foreign substances (Mu, Kaku, ×) appear to fall out of a certain range.

As a device for obtaining even higher detection accuracy, the second aspect of the present invention, which is a device for automatically detecting foreign substances contained in a dough product by capturing changes in the resonant frequency of the dough product, is proposed. We devised a non-metallic foreign object detection device. Dielectric materials have their own resonant frequencies, and dough products likewise have their own resonant frequencies. The measured values of many resonant frequencies of the dough fall within a certain range, as shown in FIG.

However, as shown in FIG. 2, the resonant frequency of a product containing foreign matter does not fall within a certain range. Foreign matter detection becomes possible by finding resonance frequencies that do not fall within a certain range through numerical processing.

[Operation] The device for detecting nonmetallic foreign matter in a dough product of the present invention can automatically detect nonmetallic foreign matter in the following manner. The non-metallic foreign matter detection device is installed in a place where the pasted product is flowing in a stable state during the manufacturing process of the pasted product, and when a foreign matter is detected, it will either indicate an abnormality or automatically remove the part that shows an abnormality. do.

As described above, according to the device for detecting non-metallic foreign matter in a dough product of the present invention, non-metallic foreign matter in a dough product can be detected without the need for an operator at all. This eliminates the need to find non-metallic foreign substances, making it possible to detect non-metallic foreign substances extremely efficiently. In addition, since it can be detected regardless of whether it is on the surface or inside the product, it is no longer possible to overlook non-metallic foreign objects. If the computer stores the coordinates of detected foreign matter and removes only that part, it becomes an extremely efficient removal device that removes only the small part of the dough that contains the foreign matter.

[Example] Hereinafter, an example of fish paste, which is considered to be the most difficult and has the worst conditions among the paste products of the present invention, will be described. FIG. 3 shows a device for detecting non-metallic foreign matter in a dough product according to the present invention. The paste product is evenly press-fitted into the space divided into two layers from the right side (horizontal) in FIG. 3. The reason for dividing into two layers is to increase the sensitivity of foreign matter detection, which is not necessary if the paste product is thin from the beginning. The electrode substrate (2) shown in the (front) and (side) portions of FIG. 3 is, for example, an electrode substrate constituted by a slip circuit. The electrodes are (7 each) shown in FIG.

In this example, since there are two layers, there are a total of two pairs of four electrode substrates. Between these electrodes, the dough is in a resonant state.

The electrode (■) uses the difference in the flow of the dough to detect only foreign matter, regardless of the non-uniformity of the dough.
It is designed to extract only the difference. A similar effect can also be obtained by using memory. ■
, ■ detect the resonance frequency at which the Q value is minimum through a multiplexer circuit. For example, if the resonant frequency is measured using a circuit as shown in FIG. 4, and if it deviates from a certain resonant frequency band, it can be determined that foreign matter is mixed in.

Next, the circuit shown in FIG. 4 mentioned above will be explained.

When the dough is excited by a voltage controlled oscillator (cvco) with a large internal resistance, the voltage amplitude between the electrodes will change as the voltage controlled oscillator (y
It becomes minimum when the frequency of co) becomes equal to fo.

At this time, the voltage controlled oscillator (VCO) is set to approximately 500 Hz.
The output of the low frequency oscillator ■ If the frequency is perturbed by 10-S, the amplitude detected output ■.

is detected as a signal with a frequency of 1000H2, twice that of f6, as shown in FIG. This V. The size of is the Q of the paste product.
It will be proportional to the value. The center frequency fc of the voltage controlled oscillator (VCO) is f. ■ When smaller. is detected as a 5001-Iz signal having an opposite phase to Vs. vice versa,
When it is larger than fcSfo, it becomes a 500 Hz signal with the same phase. Therefore,■. If it performs synchronous detection with vB and feeds back the detected output ■, to the voltage controlled oscillator (VCO), then f.

is always f. matches. At this time, V is f. The signal is proportional to .

[Effects] As described above, the device for detecting nonmetallic foreign matter in a dough product of the present invention can automatically detect nonmetallic foreign matter in a dough product manufacturing process without relying on human labor.

[Brief explanation of drawings]

Figure 1 shows the dielectric constant (ε) using the first method of the present invention.
- It is a graph of Q value, * is the value of the product with no foreign matter mixed in, and ■, M, and X are the values of the product mixed with foreign matter. Figure 2 is a diagram showing the change in the resonant frequency using the second method of the present invention, from A to B is the frequency band of the product that is free of foreign matter, and the marks, marks, and × indicate foreign matter. This is the frequency when mixed in. FIG. 3 is a projected view of the apparatus for detecting non-metallic foreign matter in a dough product, FIG. 4 is an explanatory diagram of the measuring circuit, and FIG. 5 is a diagram of the resonance state of the object to be measured. (Previous) ■Substrate for electrode (horizontal) Procedural amendment (spontaneous) 1゜Indication of incident Flat bottom 2-year patent application No. 18257 2゜Name of invention Device for detecting non-metallic foreign objects inside 3° Related to the case of the person making the amendment Patent issuer Postal code 30 Address Nozuokakeshi Hamamaru Higa 1ll119 Chijiu 91-2 Higashimikata-cho, Hamamatsu-shi, Shizuoka Prefecture Green Hill 401-4°

Claims (2)

[Claims] (1) Noodle and bread dough, mayonnaise, sausage,
Foreign matter contained in pasted products such as cosmetics and creams, specifically hair, animal hair, plastic, styrofoam, vinyl, paper, cardboard, stones, insects, wood chips, thread, rubber bands, cloth, animal bones, and animal bones. Teeth, strings, etc., are combined in a multidimensional manner with parameters that electromagnetically express the properties of materials at frequencies near the resonant frequency of the paste product, specifically the relationship between dielectric constant (ε) and loss coefficient (D), Dielectric constant (
A device for detecting nonmetallic foreign matter in a dough product, characterized in that it automatically detects nonmetallic foreign matter by using the relationship of ε)-Q value, etc. (2) Noodle and bread dough, mayonnaise, sausage,
Foreign matter contained in pasted products such as cosmetics and creams, specifically hair, animal hair, plastic, styrofoam, vinyl, paper, cardboard, stones, insects, wood chips, thread, rubber bands, cloth, animal bones, and animal bones. A device for detecting non-metallic foreign matter in a dough product, which is characterized by automatically detecting teeth, strings, etc. by capturing changes in the resonance frequency of the dough product.