JP2007040918A

JP2007040918A - Preservative detection method and device

Info

Publication number: JP2007040918A
Application number: JP2005227635A
Authority: JP
Inventors: Keizo Mochizuki; 恵三望月; Hidejiro Hara; 秀二郎原; Yoshitaka Nomura; 芳敬野村; Yoshito Saito; 義人斉藤
Original assignee: Freund Corp
Current assignee: Freund Corp
Priority date: 2005-08-05
Filing date: 2005-08-05
Publication date: 2007-02-15
Also published as: WO2007018056A1

Abstract

<P>PROBLEM TO BE SOLVED: To provide a preservative detection method and a preservative detection device capable of detecting precisely and stably the presence of a preservative comprising a non-magnetic material added to a packed food. <P>SOLUTION: This preservative detection device for detecting the presence of the preservative comprising the non-magnetic material added to the packed food 6, detects the presence of the preservative, by measuring one or more selected out of a group comprising a phase angle of an impedance Z-value, as an impedance characteristic, a resistance value Rs value in an equivalent series circuit mode, and an electrostatic capacitance Cs in the equivalent series circuit mode, using a device provided with a measuring instrument 30 for measuring the impedance characteristic of the packed food 6, and a control part 4 for storing an allowance range of the impedance characteristic of the packed food preset based on a measured value of the impedance characteristic of the packed food in which the presence of the preservative is known, and for comparing the measured value of the impedance characteristic of the packed food 6 measured by the measuring instrument 30, with the allowance range, to determine the presence of the preservative in the packed food 6. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

本発明は、包装食品中に添付された非磁性材料からなる食品用保存剤の有無を、非破壊検査法により検出する保存剤検出方法および保存剤検出装置に関する。 The present invention relates to a preservative detection method and a preservative detection device for detecting the presence or absence of a food preservative made of a nonmagnetic material attached to a packaged food by a nondestructive inspection method.

市販されている包装食品のうち、水分活性値が０．６５未満の食品は保存性が高く、保存時にカビが繁殖する恐れが少なく、カビの繁殖による品質劣化は受け難い。一方、水分含量が高く、水分活性値が０．９を超える食品の保存性を確保する場合は、冷凍食品またはレトルト等の形態に加工されることから、包装食品中に保存剤を添付する必要はない。 Among the commercially available packaged foods, foods having a water activity value of less than 0.65 have high storage stability and are less likely to cause mold growth during storage, and are less susceptible to quality deterioration due to mold growth. On the other hand, when preserving food with a high water content and water activity value exceeding 0.9, it is processed into a form such as frozen food or retort, so a preservative must be attached to the packaged food. There is no.

しかしながら、水分活性値が０．６５以上、０．９以下の中間水分製品と称せられる半生包装食品においては、カビの繁殖によって流通時に品質劣化の起こる可能性が高い。このため中間水分製品においては、包装食品の品質劣化を抑制するため、該包装食品中に、基材にエタノール水溶液を含浸させた保存剤（以下、エタノール配合保存剤という。）や脱酸素剤が添付されることが多い。
脱酸素剤やエタノール配合保存剤を包装食品中に添付することによって、無添付時には１〜２週間でカビが繁殖して商品価値が消失するような商品も、脱酸素やエタノール蒸散による防カビ効果により、カビの繁殖を数ヶ月以上抑制することが可能となる。この結果、商品の賞味期限が長くなり、遠距離配送や、比較的長い期間、市場展開が可能となり、計画的販売、生産が可能となる。 However, in semi-packaged foods called intermediate moisture products having a water activity value of 0.65 or more and 0.9 or less, there is a high possibility that quality deterioration will occur during distribution due to mold growth. Therefore, in the intermediate moisture product, in order to suppress the deterioration of the quality of the packaged food, there is a preservative (hereinafter referred to as ethanol-containing preservative) or an oxygen scavenger in which the base material is impregnated with an aqueous ethanol solution. Often attached.
By attaching an oxygen scavenger or preservative containing ethanol to the packaged food, it is possible to prevent molds from deoxidizing or ethanol transpiration, even if there is no product attached and the mold propagates in 1 to 2 weeks. Therefore, it is possible to suppress the growth of mold for several months or more. As a result, the shelf life of the product becomes long, enabling long-distance delivery and market development for a relatively long period of time, enabling planned sales and production.

ところが、このような中間水分製品において、何らかの手違いによって、保存剤を添付し忘れた包装食品が市場に出荷された場合には、１〜２週間でカビが繁殖し、商品価値が消失すると共に、メーカーの信頼が大きく損なわれ、多大な損害を被ることになる。
このような保存剤無添付製品の市場への出荷を防止するため、保存剤の有無を検出する保存剤検出方法が用いられている。保存剤検出方法の従来技術として、鉄剤を含有している脱酸素剤については、金属検知機を使用して添付の有無を確認する方法がある。また、エタノール配合保存剤については、該保存剤に鉄剤を配合し、金属検知器を用いて検査する方法がある。 However, in such an intermediate moisture product, when a packaged food that has been forgotten to attach a preservative is shipped to the market due to some mistake, mold grows in one to two weeks, and the commercial value disappears. The manufacturer's trust is greatly impaired, and a great deal of damage is incurred.
In order to prevent such preservative-free products from being shipped to the market, a preservative detection method for detecting the presence or absence of a preservative is used. As a prior art of the preservative detection method, there is a method of confirming whether or not an oxygen scavenger containing an iron agent is attached using a metal detector. As for the ethanol preservative, there is a method in which an iron agent is blended with the preservative and inspected using a metal detector.

下記特許文献１には、包装食品中の保存剤に鉄剤を配合し、被検出物内に金属が含まれているか否かを検出する機能と、被検出物内に所定量の金属が含まれているか否かを検出する機能とを有する装置を用いる方法が記載されている。この方法によれば、金属の有無を検知するとともに、該金属が保存剤中に添加された金属か、異物として混入した金属かの判別を行うことによって、包装食品中における保存剤の有無を検査することができる。 In the following Patent Document 1, a function of detecting whether or not a metal is contained in an object to be detected by adding an iron agent to a preservative in packaged food, and a predetermined amount of metal is contained in the object to be detected. A method using an apparatus having a function of detecting whether or not a device is in use is described. According to this method, the presence or absence of a metal is detected, and the presence or absence of the preservative in the packaged food is inspected by determining whether the metal is a metal added to the preservative or a metal mixed as a foreign substance. can do.

また、本発明者等は下記特許文献２において、包装食品のインピーダンス特性電圧値を測定することによって、非磁性材料からなる保存剤の有無を検出する方法を既に提案している。
特開平７−３２５１５９号公報特開２００５−１５６１６７号公報 In addition, in the following Patent Document 2, the present inventors have already proposed a method for detecting the presence or absence of a preservative made of a nonmagnetic material by measuring the impedance characteristic voltage value of packaged food.
JP 7-325159 A JP 2005-156167 A

しかしながら、包装食品中の保存剤の有無を検出する方法として金属探知機や特許文献１に開示の検出方法を採用した場合、金属類が異物として包装食品中に混入したときに、該金属類の量によっては、これを異物と判断できずに保存剤無添付製品が市場へ出荷される可能性がある。
また、本来、鉄剤の配合が不必要であるエタノール配合保存剤に、保存剤の検出を目的として鉄剤のような磁性材料を配合することは、保存剤の製造に余分な工程を必要とし、好ましいものではない。 However, when the metal detector or the detection method disclosed in Patent Document 1 is used as a method for detecting the presence or absence of a preservative in the packaged food, when the metal is mixed in the packaged food as a foreign object, Depending on the amount, a product without a preservative may be shipped to the market without being judged as a foreign object.
In addition, blending a magnetic material such as an iron agent for the purpose of detecting a preservative with an ethanol-containing preservative that originally does not require the incorporation of an iron agent requires an extra step in the production of the preservative, which is preferable. It is not a thing.

一方、特許文献２に記載の方法では、非磁性材料からなる保存剤の有無を検出できるものの、保存剤が添付されていない包装食品（保存剤無添付品）と保存剤が添付された包装食品（保存剤添付品）とのインピーダンス特性電圧値の差は小さく、かつ周波数２０ｋＨｚ以上４０ｋＨｚ以下の限られた範囲のインピーダンス特性電圧値の差だけで検出を行うために、包装食品の包装形態によっては、保存剤の有無の検出精度が不安定になることがある。 On the other hand, the method described in Patent Document 2 can detect the presence or absence of a preservative made of a non-magnetic material, but does not have a preservative attached to the packaged food (preservative-free product) and the prepackaged food to which the preservative is attached. The difference in impedance characteristic voltage value with (preservative attachment) is small, and detection is performed only by the difference in impedance characteristic voltage value in a limited range of frequency 20 kHz to 40 kHz. The detection accuracy of the presence or absence of a preservative may become unstable.

本発明は、包装食品中に添付された非磁性材料からなる保存剤の有無を、高い精度で、安定して検出できる保存剤検出方法および保存剤検出装置を提供することを目的とする。 An object of this invention is to provide the preservative detection method and preservative detection apparatus which can detect stably the presence or absence of the preservative which consists of a nonmagnetic material attached to packaged food with high precision.

前記課題を解決するために、本発明の保存剤検出方法は、包装食品のインピーダンス特性を測定することによって、該包装食品中に添付した非磁性材料からなる保存剤の有無を検出する方法であって、前記インピーダンス特性として、インピーダンスＺ値の位相角、等価直列回路モードにおける抵抗値Ｒｓ値、等価直列回路モードにおける静電容量Ｃｓ値から選ばれる１以上を用いることを特徴とする。 In order to solve the above-mentioned problems, the preservative detection method of the present invention is a method for detecting the presence or absence of a preservative made of a nonmagnetic material attached to the packaged food by measuring impedance characteristics of the packaged food. As the impedance characteristic, one or more selected from the phase angle of the impedance Z value, the resistance value Rs value in the equivalent series circuit mode, and the capacitance Cs value in the equivalent series circuit mode are used.

本発明の保存剤検出装置は、包装食品中に添付した非磁性材料からなる保存剤の有無を検出する保存剤検出装置であって、包装食品のインピーダンス特性を測定する測定装置と、保存剤の有無が知られている包装食品のインピーダンス特性の測定値に基づいて予め設定された包装食品のインピーダンス特性の許容範囲を記憶し、前記測定装置による包装食品のインピーダンス特性の測定値を前記許容範囲と比較して包装食品中の保存剤の有無を判定する制御部とを備えてなり、前記インピーダンス特性が、インピーダンスＺ値の位相角、等価直列回路モードにおける抵抗値Ｒｓ値、および等価直列回路モードにおける静電容量Ｃｓ値から選ばれる１以上であることを特徴とする。 The preservative detection device of the present invention is a preservative detection device for detecting the presence or absence of a preservative made of a nonmagnetic material attached to a packaged food, a measuring device for measuring impedance characteristics of the packaged food, The tolerance value of the impedance characteristic of the packaged food set in advance based on the measurement value of the impedance characteristic of the packaged food whose presence or absence is known is stored, and the measurement value of the impedance characteristic of the packaged food by the measurement device is the tolerance range. And a control unit for determining the presence or absence of a preservative in the packaged food, and the impedance characteristics are the phase angle of the impedance Z value, the resistance value Rs value in the equivalent series circuit mode, and the equivalent series circuit mode. It is one or more selected from the capacitance Cs value.

また本発明は、包装食品中に添付した非磁性材料からなる保存剤の有無を検出する保存剤検出装置であって、包装食品のインピーダンス特性を測定する測定装置と、保存剤の有無が知られている包装食品のインピーダンス特性の測定値に基づいて予め設定された包装食品のインピーダンス特性の許容範囲を記憶し、前記測定装置による包装食品のインピーダンス特性の測定値を前記許容範囲と比較して包装食品中の保存剤の有無を判定する制御部とを備えてなり、前記測定装置が、互いに対向配置された２枚の電磁波発信極板と、該２枚の電磁波発信極板の間に配置された１枚の電磁波受信極板とを備えており、前記電磁波発信極板は、前記包装食品が載置される面に平行な第１の板部と、該第１の板部に垂直な第２の板部とからなる断面Ｌ字状であることを特徴とする保存剤検出装置を提供する。 The present invention also relates to a preservative detection device for detecting the presence or absence of a preservative made of a nonmagnetic material attached to a packaged food, a measuring device for measuring impedance characteristics of the packaged food, and the presence or absence of the preservative. Storing a preset allowable range of the impedance characteristic of the packaged food based on the measured value of the impedance characteristic of the packaged food, and comparing the measured value of the impedance characteristic of the packaged food by the measuring device with the allowable range And a control unit for determining the presence or absence of a preservative in the food, wherein the measuring device is disposed between two electromagnetic wave transmitting electrode plates disposed opposite to each other and between the two electromagnetic wave transmitting electrode plates. A plurality of electromagnetic wave receiving electrode plates, wherein the electromagnetic wave transmitting electrode plate includes a first plate part parallel to a surface on which the packaged food is placed, and a second plate perpendicular to the first plate part. Cross section L made of plate Providing preservative detector which is a Jo.

本発明によれば、包装食品中に添付された非磁性材料からなる保存剤の有無を、高い精度で、安定して検出できる保存剤検出方法および保存剤検出装置が得られる。 ADVANTAGE OF THE INVENTION According to this invention, the preservative detection method and preservative detection apparatus which can detect stably the presence or absence of the preservative which consists of a nonmagnetic material attached to packaged food with high precision are obtained.

本発明における検出対象としての保存剤は、鉄剤等の磁性材料を含有しない、非磁性材料からなる保存剤であり、好ましくは、基材にエタノール水溶液を含浸させた保存剤（エタノール配合保存剤）である。
エタノール配合保存剤を包装体中に添付すると、包装体内部でエタノールが蒸散し、生じたエタノール蒸気によって殺菌効果が得られる。 The preservative as a detection target in the present invention is a preservative made of a non-magnetic material that does not contain a magnetic material such as an iron agent, and preferably a preservative (ethanol-containing preservative) in which a base material is impregnated with an aqueous ethanol solution. It is.
When an ethanol preservative is attached to the package, ethanol evaporates inside the package, and the resulting ethanol vapor provides a bactericidal effect.

エタノール配合保存剤の具体例としては、シリカゲルにエタノール水溶液を含浸させた粉体状保存剤、水性ゲルにエタノール水溶液を含浸させた水性ゲル状保存剤、パルプシートにエタノール水溶液を含浸させたエタノール含浸パルプシート保存剤等が挙げられる。
エタノール配合保存剤に含有されているエタノール水溶液、すなわち基材に含浸されているエタノール水溶液のエタノール濃度は２０〜９５質量％の範囲内が好ましい。該エタノール濃度が２０質量％未満では、エタノール蒸気による殺菌力が不足し好ましくない。一方、エタノール濃度が９５質量％を超える場合には、保存剤が高価となり、経済的でなく好ましくない。 Specific examples of ethanol preservatives include powdery preservatives in which silica gel is impregnated with an aqueous ethanol solution, aqueous gel preservatives in which an aqueous gel is impregnated with an aqueous ethanol solution, and ethanol impregnation in which a pulp sheet is impregnated with an aqueous ethanol solution. Examples thereof include a pulp sheet preservative.
The ethanol concentration of the ethanol aqueous solution contained in the ethanol preservative, that is, the ethanol aqueous solution impregnated in the substrate is preferably in the range of 20 to 95% by mass. If the ethanol concentration is less than 20% by mass, the sterilizing power by ethanol vapor is insufficient, which is not preferable. On the other hand, when the ethanol concentration exceeds 95% by mass, the preservative becomes expensive, which is not economical and not preferable.

図１および図２は、本発明の保存剤検出装置の一実施形態を示したもので、図１は概略構成図、図２は検出部１の要部を拡大して示した斜視図である。
本実施形態の装置は、包装食品６を搬送する搬送装置２と、該包装食品６の搬送経路上に設けられた検出部１と、検出部１にある包装食品６のインピーダンス特性を測定する測定装置３０と、測定装置３０による測定結果に基づいて保存剤の有無を判定する制御部４と、この制御部４の判定結果に基づいて保存剤無添付製品を搬送装置２から排除する排除装置５とを備えている。
測定装置３０は、検出部１に設けられた、互いに対向配置された２枚の電磁波発信極板１２ａ、１２ｂおよび該２枚の電磁波発信極板の間に設けられた１枚の電磁波受信極板１３と、検出部１の外に設けられた計測器３を備えている。 1 and 2 show an embodiment of a preservative detection apparatus according to the present invention. FIG. 1 is a schematic configuration diagram, and FIG. 2 is an enlarged perspective view showing a main part of the detection unit 1. .
The apparatus of this embodiment measures the impedance characteristic of the conveying device 2 that conveys the packaged food 6, the detection unit 1 provided on the conveyance path of the packaged food 6, and the packaged food 6 in the detection unit 1. The apparatus 30, the control unit 4 that determines the presence or absence of a preservative based on the measurement result of the measurement device 30, and the exclusion device 5 that excludes the preservative-free product from the transport device 2 based on the determination result of the control unit 4 And.
The measuring device 30 includes two electromagnetic wave transmission electrode plates 12a and 12b disposed in the detection unit 1 and opposed to each other, and one electromagnetic wave reception electrode plate 13 provided between the two electromagnetic wave transmission electrode plates. A measuring instrument 3 provided outside the detection unit 1 is provided.

搬送装置２は、包装食品６を搬送するための包装食品搬送手段である。本実施形態における搬送装置２は、搬送コンベアー２１と、該搬送コンベアー２１を駆動させるためのコンベアー駆動ローラー２２，２３とから構成されている。 The transport device 2 is a packaged food transport means for transporting the packaged food 6. The transport apparatus 2 in this embodiment includes a transport conveyor 21 and conveyor drive rollers 22 and 23 for driving the transport conveyor 21.

検出部１は、基板１４と、断面コ字状の第１の電磁波遮蔽板１１ａとからなる筒状体の内部空間７を搬送コンベアー２１が通過するように構成されている。
基板１４は、図２に示すように、中央部に矩形の開口部１５ａが設けられた枠板１５と、側板１６，１６と、第２の電磁波遮蔽板１１ｂとからなり、内部に空間を有する箱状に形成されている。本実施形態において、枠板１５の開口部１５ａの四辺に平行な二方向をＸ方向、Ｙ方向とし、該Ｘ方向およびＹ方向の両方に垂直な方向をＺ方向とする。図２には示していないが、前記第１の電磁波遮蔽板１１ａは枠板１５上に設けられている。
本実施形態において、搬送コンベアー２１の上面（包装食品６が載置される面）はＺ方向に垂直な面（Ｘ−Ｙ平面）であり、包装食品６の搬送方向はＸ方向である。 The detection unit 1 is configured such that the transport conveyor 21 passes through an inner space 7 of a cylindrical body composed of a substrate 14 and a first electromagnetic wave shielding plate 11a having a U-shaped cross section.
As shown in FIG. 2, the substrate 14 includes a frame plate 15 having a rectangular opening 15a at the center, side plates 16 and 16, and a second electromagnetic wave shielding plate 11b, and has a space inside. It is formed in a box shape. In the present embodiment, two directions parallel to the four sides of the opening 15a of the frame plate 15 are defined as an X direction and a Y direction, and a direction perpendicular to both the X direction and the Y direction is defined as a Z direction. Although not shown in FIG. 2, the first electromagnetic wave shielding plate 11 a is provided on the frame plate 15.
In this embodiment, the upper surface of the conveyor 21 (the surface on which the packaged food 6 is placed) is a surface (XY plane) perpendicular to the Z direction, and the conveyance direction of the packaged food 6 is the X direction.

枠板１５のＸ方向中央部において、枠板１５上に、棒状の電磁波受信極板１３がＹ方向に沿って設けられている。該電磁波受信極板１３は開口部１５ａを介して、枠板１５の一端部から他端部に架け渡すように設けられ、枠板１５の上面に固定されている。電磁波受信極板１３の、Ｙ方向に垂直な断面における形状は矩形である。
電磁波受信極板１３のＸ方向両側には、それぞれＹ方向に垂直な断面形状がＬ字状の電磁波発信極板１２ａ、１２ｂが、Ｙ方向に沿って設けられている。一方の電磁波発信極板１２ｂから他方の電磁波発信極板１２ａへ向かう方向がＸ方向である。
電磁波発信極板１２ａ、１２ｂは、互いに垂直な第１の板部１２Ａと第２の板部１２Ｂとからなっており、第２の板部１２Ｂの両角部には、それぞれ矩形の段部１２Ｃが切り欠き形成されている。
そして、第２の板部１２Ｂが電磁波受信極板１３の側面と近接して対向するように、該第２の板部１２Ｂを枠板１５の開口部１５ａに挿入し、段部１２Ｃを枠板１５上面に載せた状態で固定されている。
電磁波発信極板１２ａ、１２ｂの第１の板部１２Ａの上面と、電磁波受信極板１３の上面は面一となっており、搬送コンベアー２１の、包装食品６が載置された搬送コンベアー２１が、これらの上面に接触しながら走行するように構成されている。 A rod-shaped electromagnetic wave receiving electrode plate 13 is provided on the frame plate 15 along the Y direction at the center in the X direction of the frame plate 15. The electromagnetic wave receiving electrode plate 13 is provided so as to span from one end portion of the frame plate 15 to the other end portion through the opening 15 a, and is fixed to the upper surface of the frame plate 15. The shape of the electromagnetic wave receiving electrode plate 13 in a cross section perpendicular to the Y direction is a rectangle.
On both sides in the X direction of the electromagnetic wave receiving electrode plate 13, electromagnetic wave transmitting electrode plates 12a and 12b each having an L-shaped cross section perpendicular to the Y direction are provided along the Y direction. The direction from one electromagnetic wave transmitting electrode plate 12b to the other electromagnetic wave transmitting electrode plate 12a is the X direction.
The electromagnetic wave transmission electrode plates 12a and 12b are composed of a first plate portion 12A and a second plate portion 12B which are perpendicular to each other, and rectangular step portions 12C are provided at both corners of the second plate portion 12B. Notches are formed.
Then, the second plate portion 12B is inserted into the opening portion 15a of the frame plate 15 so that the second plate portion 12B faces the side surface of the electromagnetic wave receiving electrode plate 13 in close proximity, and the step portion 12C is inserted into the frame plate. 15 is fixed on the top surface.
The upper surface of the first plate portion 12A of the electromagnetic wave transmission electrode plates 12a and 12b and the upper surface of the electromagnetic wave reception electrode plate 13 are flush with each other, and the conveyance conveyor 21 on which the packaged food 6 is placed is provided on the conveyance conveyor 21. The vehicle is configured to travel while being in contact with these upper surfaces.

２枚の電磁波発信極板１２ａ、１２ｂの寸法は同一である。Ｘ方向における電磁波発信極板１２ａ、１２ｂの幅Ｗ２は１ｍｍ以上５０ｍｍ以下が好ましく、１ｍｍ以上３０ｍｍ以下がより好ましい。
Ｗ２が１ｍｍ未満の場合は各インピーダンス特性値が安定せず好ましくない。一方、Ｗ２を大きくした結果、Ｘ方向における電磁波発信極板１２ａ、１２ｂの一端から他端までの距離（すなわち、Ｗ２＋Ｗ１＋Ｗ３＋Ｗ１＋Ｗ２の合計）が保存剤の長さ方向の寸法よりも大きくなると、検出精度が低下して好ましくない。 The two electromagnetic wave transmission electrode plates 12a and 12b have the same dimensions. The width W2 of the electromagnetic wave transmission electrode plates 12a and 12b in the X direction is preferably 1 mm or more and 50 mm or less, and more preferably 1 mm or more and 30 mm or less.
When W2 is less than 1 mm, each impedance characteristic value is not stable, which is not preferable. On the other hand, if the distance from one end to the other end of the electromagnetic wave transmission electrode plates 12a, 12b in the X direction (ie, the sum of W2 + W1 + W3 + W1 + W2) becomes larger than the lengthwise dimension of the preservative as a result of increasing W2, Decreasing and not preferable.

Ｚ方向における電磁波受信極板１３の高さＨ３は、０．５ｍｍ以上、Ｘ方向における電磁波受信極板１３の幅Ｗ３と同等以下であることが好ましい。
Ｈ３が０．５ｍｍ未満では機械的強度が不足し、一方、Ｈ３がＷ３よりも大きいと、理由は明確ではないが、ノイズ信号が生じ易く、好ましくない。Ｈ３は、より好ましくは、１ｍｍ以上、Ｗ３以下である。 The height H3 of the electromagnetic wave reception electrode plate 13 in the Z direction is preferably 0.5 mm or more and equal to or less than the width W3 of the electromagnetic wave reception electrode plate 13 in the X direction.
If H3 is less than 0.5 mm, the mechanical strength is insufficient. On the other hand, if H3 is greater than W3, the reason is not clear, but a noise signal is easily generated, which is not preferable. H3 is more preferably 1 mm or more and W3 or less.

Ｚ方向における電磁波発信極板１２ａ、１２ｂの高さＨ２は、電磁波受信極板１３の高さＨ３の１倍以上３倍以下であることが好ましく、１倍以上２倍以下がより好ましい。
Ｈ２が上記範囲より小さいとノイズ信号が生じ易く好ましくない。一方、上記範囲より大きいと、理由は明確ではないが検出感度が低下し、好ましくない。
電磁波発信極板１２ａ、１２ｂの高さＨ２と電磁波受信極板１３の高さＨ３とが等しい場合は、第２の板部１２Ｂに段部１２Ｃは設けない。 The height H2 of the electromagnetic wave transmitting electrode plates 12a and 12b in the Z direction is preferably 1 to 3 times the height H3 of the electromagnetic wave receiving electrode plate 13, and more preferably 1 to 2 times.
If H2 is smaller than the above range, a noise signal is likely to be generated, which is not preferable. On the other hand, if it is larger than the above range, the detection sensitivity is lowered, although the reason is not clear, it is not preferable.
When the height H2 of the electromagnetic wave transmission electrode plates 12a and 12b and the height H3 of the electromagnetic wave reception electrode plate 13 are equal, the step portion 12C is not provided in the second plate portion 12B.

Ｘ方向における電磁波受信極板１３の幅Ｗ３は、０．５ｍｍ以上１５ｍｍ以下が好ましい。該幅Ｗ３が０．５ｍｍ未満では、理由は明確ではないが、測定の安定性が悪く好ましくない。一方、Ｗ３が１５ｍｍを超える場合には、理由は明確ではないが、ノイズ信号が生じ易く、好ましくない。Ｗ３のより好ましい範囲は１ｍｍ以上１０ｍｍ以下である。 The width W3 of the electromagnetic wave receiving electrode plate 13 in the X direction is preferably 0.5 mm or more and 15 mm or less. If the width W3 is less than 0.5 mm, the reason is not clear, but the measurement stability is poor and is not preferable. On the other hand, when W3 exceeds 15 mm, the reason is not clear, but a noise signal is easily generated, which is not preferable. A more preferable range of W3 is 1 mm or more and 10 mm or less.

Ｘ方向における電磁波発信極板１２ａ、１２ｂと電磁波受信極板１３との間隔Ｗ１は、１ｍｍ以上、３０ｍｍ以下が好ましい。該Ｗ１が１ｍｍ未満の場合には、理由は明白ではないが、検出部１内に包装食品６が有っても無くても測定値が同程度となり、保存剤の有無を検出できない。一方、Ｗ１を大きくした結果、Ｘ方向における電磁波発信極板１２ａ、１２ｂの一端から他端までの距離（すなわち、Ｗ２＋Ｗ１＋Ｗ３＋Ｗ１＋Ｗ２の合計）が保存剤の長さ方向の寸法よりも大きくなると、検出精度が低下して好ましくない。Ｗ１のより好ましい範囲は１ｍｍ以上２０ｍｍ以下である。 The interval W1 between the electromagnetic wave transmission electrode plates 12a and 12b and the electromagnetic wave reception electrode plate 13 in the X direction is preferably 1 mm or more and 30 mm or less. When W1 is less than 1 mm, the reason is not clear, but the measured values are almost the same regardless of whether or not the packaged food 6 is present in the detection unit 1, and the presence or absence of a preservative cannot be detected. On the other hand, as a result of increasing W1, if the distance from one end to the other end of the electromagnetic wave transmission plates 12a, 12b in the X direction (that is, the sum of W2 + W1 + W3 + W1 + W2) is larger than the lengthwise dimension of the preservative, the detection accuracy is improved. Decreasing and not preferable. A more preferable range of W1 is 1 mm or more and 20 mm or less.

電磁波発信極板１２ａ、１２ｂおよび電磁波受信極板１３の材料としては、アルミニウム板、ステンレス板、銅板等の導電性の良い金属、及び通電性プラスチック板などを用いることができる。また、電磁波発信極板１２ａ、１２ｂおよび電磁波受信極板１３の上面、すなわち搬送コンベアー２１と接触する面上にフッ素系樹脂からなる被覆層を設けてもよい。
基板１４の枠板１５および側板１６，１６の材料としては、ポリ塩化ビニル樹脂板、ポリエチレン樹脂板、ポリスチロール樹脂板、ポリフッ素樹脂板、ポリアクリル樹脂板などの電気絶縁性プラスチック板が用いられる。
第１の電磁波遮蔽板１１ａおよび第２の電磁波遮蔽板１１ｂは、電磁波発信極板１２ａ、１２ｂおよび電磁波受信極板１３に対する外部からのノイズ電磁波の影響、および電磁波発信極板１２ａ、１２ｂから発信される電磁波が外部に漏出することによる不都合を抑制できるものであればよい。第１の電磁波遮蔽板１１ａおよび第２の電磁波遮蔽板１１ｂの材料としては、例えばステンレス板、アルミニウム板、銅板などの導電性材料が挙げられる。
第１の電磁波遮蔽板１１ａおよび第２の電磁波遮蔽板１１ｂは、電磁波発信極板１２ａ、１２ｂおよび電磁波受信極板１３、並びにこれらに接続されたリード線８１、８２、９１、９２に対して絶縁状態となるように配置される。 As a material for the electromagnetic wave transmitting electrode plates 12a and 12b and the electromagnetic wave receiving electrode plate 13, a metal having good conductivity such as an aluminum plate, a stainless steel plate, a copper plate, and a conductive plastic plate can be used. Moreover, you may provide the coating layer which consists of fluorine-type resin on the upper surface of the electromagnetic wave transmission electrode plates 12a and 12b and the electromagnetic wave reception electrode plate 13, ie, the surface which contacts the conveyance conveyor 21.
As the material of the frame plate 15 and the side plates 16 and 16 of the substrate 14, an electrically insulating plastic plate such as a polyvinyl chloride resin plate, a polyethylene resin plate, a polystyrene resin plate, a polyfluororesin plate, or a polyacrylic resin plate is used. .
The first electromagnetic wave shielding plate 11a and the second electromagnetic wave shielding plate 11b are transmitted from the electromagnetic wave transmitting electrode plates 12a and 12b and the electromagnetic wave transmitting electrode plates 12a and 12b. What is necessary is just to be able to suppress inconvenience due to leakage of electromagnetic waves to the outside. Examples of the material of the first electromagnetic wave shielding plate 11a and the second electromagnetic wave shielding plate 11b include conductive materials such as a stainless steel plate, an aluminum plate, and a copper plate.
The first electromagnetic wave shielding plate 11a and the second electromagnetic wave shielding plate 11b are insulated from the electromagnetic wave transmission electrode plates 12a and 12b and the electromagnetic wave reception electrode plate 13 and the lead wires 81, 82, 91 and 92 connected thereto. Arranged to be in a state.

計測器３は、電磁波発信極板１２ａ、１２ｂから所定周波数の電磁波を発信して、電磁波受信極板１３で受信することにより、電磁波発信極板１２ａ、１２ｂと電磁波受信極板１３の間の内部空間７のインピーダンス特性を測定するもので、インピーダンスＺ値の位相角、等価直列回路モードにおける抵抗値Ｒｓ値、および等価直列回路モードにおける静電容量Ｃｓ値のうちの１以上を計測できる装置が用いられる。
具体的には、ＬＣＲハイテスター３５３２−５０（日置電機（株）製）を使用することができる。 The measuring instrument 3 transmits an electromagnetic wave having a predetermined frequency from the electromagnetic wave transmission electrode plates 12 a and 12 b and receives the electromagnetic wave at the electromagnetic wave reception electrode plate 13, so that the inside between the electromagnetic wave transmission electrode plates 12 a and 12 b and the electromagnetic wave reception electrode plate 13 is received. A device that measures impedance characteristics of the space 7 and can measure one or more of the phase angle of the impedance Z value, the resistance value Rs value in the equivalent series circuit mode, and the capacitance Cs value in the equivalent series circuit mode. It is done.
Specifically, an LCR high tester 3532-50 (manufactured by Hioki Electric Co., Ltd.) can be used.

計測器３は、リード線８１、８２、９１、９２を介して、電磁波発信極板１２ａ、１２ｂおよび電磁波受信極板１３と電気的に接続されている。
具体的には計測器３の電磁波送信端子３１、３２は、リード線８１、８２を介して電磁波発信極板１２ａ、１２ｂにそれぞれ接続されており、計測器３の電磁波受信端子３３、３４はリード線９１、９２を介して電磁波受信極板１３に接続されている。 The measuring instrument 3 is electrically connected to the electromagnetic wave transmitting electrode plates 12 a and 12 b and the electromagnetic wave receiving electrode plate 13 via lead wires 81, 82, 91 and 92.
Specifically, the electromagnetic wave transmission terminals 31 and 32 of the measuring instrument 3 are connected to the electromagnetic wave transmitting electrode plates 12a and 12b via lead wires 81 and 82, respectively, and the electromagnetic wave receiving terminals 33 and 34 of the measuring instrument 3 are leads. The electromagnetic wave receiving electrode plate 13 is connected via lines 91 and 92.

このように構成された計測器３によれば、包装食品６が電磁波発信極板１２ａ、１２ｂおよび電磁波受信極板１３の上を通過する際に、電磁波受信極板１３から計測器３に送られる出力に変化が生じ、この変化に基づいて検出部１の内部空間７のインピーダンス特性変化を計測することができる。 According to the measuring instrument 3 configured as described above, the packaged food 6 is sent from the electromagnetic wave receiving electrode plate 13 to the measuring instrument 3 when passing over the electromagnetic wave transmitting electrode plates 12 a and 12 b and the electromagnetic wave receiving electrode plate 13. A change occurs in the output, and a change in impedance characteristics of the internal space 7 of the detection unit 1 can be measured based on this change.

また計測器３は、測定したインピーダンス特性の値に基づいて発生させた信号電圧を、制御部４に送信する機能を有する。
計測器３の信号出力端子３５は、リード線９３を介して制御部４の信号受信端子４１に接続されている。 The measuring instrument 3 has a function of transmitting a signal voltage generated based on the measured impedance characteristic value to the control unit 4.
The signal output terminal 35 of the measuring instrument 3 is connected to the signal receiving terminal 41 of the control unit 4 via a lead wire 93.

制御部４は、保存剤の有無が既知の包装食品６が検出部１を通過するときに受け取る信号電圧の範囲を記憶するメモリ（記憶部、図示せず）を内蔵している。これにより、包装食品６のインピーダンス特性の許容範囲を予め制御部４に設定しておくことができる。
そして、制御部４は、保存剤の有無が未知の被験包装食品６が検出部１を通過するときに受け取る信号電圧を前記許容範囲と比較することにより、被験包装食品６中の保存剤の有無の判定を行う。 The control unit 4 has a built-in memory (storage unit, not shown) that stores a range of signal voltages received when the packaged food 6 having a known presence or absence of a preservative passes through the detection unit 1. Thereby, the tolerance | permissible_range of the impedance characteristic of the packaged food 6 can be set to the control part 4 previously.
And the control part 4 compares the signal voltage received when the test packaging food 6 with which the presence or absence of a preservative is unknown passes the detection part 1 with the said tolerance | permissible_range, The presence or absence of the preservative in the test packaging food 6 Judgment is made.

制御部４の駆動制御信号発信端子４２は、リード線９４を介して排除装置５の駆動制御信号受信端子５２に接続されている。
制御部４は、被験包装食品６中の保存剤の有無を判定した判定結果に基づいて、排除装置５に信号を送り、排除装置５は該信号に基づいて包装食品移動制御棒５１の位置を変え、搬送コンベアー２１によって搬送される被験包装食品６の排出方向を制御するようになっている。 The drive control signal transmission terminal 42 of the control unit 4 is connected to the drive control signal reception terminal 52 of the exclusion device 5 via a lead wire 94.
The control unit 4 sends a signal to the exclusion device 5 based on the determination result of determining the presence or absence of the preservative in the test packaged food 6, and the exclusion device 5 determines the position of the packaged food movement control rod 51 based on the signal. In other words, the discharge direction of the test packaged food 6 conveyed by the conveyor 21 is controlled.

例えば、制御部４は、被験包装食品６に保存剤が添付されていると判定した時には、排除装置５の包装食品移動制御棒５１を搬送コンベアー２１の移行方向と平行する方向に固定し、被験包装食品６を保存剤有りの正常製品として直進移行させる。また、被験包装食品６に保存剤が添付されていないと判定した時には、排除装置５の包装食品移動制御棒５１を搬送コンベアー２１の移行方向と交差する方向に駆動し、被験包装食品６を保存剤無しの不良製品として、搬送コンベアー２１の直進移行方向と異なる方向に排除する等の排除方式を用いることができる。 For example, when the control unit 4 determines that the preservative is attached to the test packaged food 6, the control unit 4 fixes the packaged food movement control rod 51 of the exclusion device 5 in a direction parallel to the transfer direction of the transport conveyor 21. The packaged food 6 is moved straight as a normal product with a preservative. When it is determined that the preservative is not attached to the test packaged food 6, the packaged food movement control rod 51 of the exclusion device 5 is driven in a direction intersecting the transfer direction of the transport conveyor 21 to store the test packaged food 6. As the defective product without the agent, it is possible to use an exclusion method such as exclusion in a direction different from the direction of straight movement of the conveyor 21.

本実施形態の保存剤検出装置を用いて、保存剤を検出するには、予め、保存剤を添付した包装食品（保存剤添付品）および保存剤を添付していない包装食品（保存剤無添付品）について、それぞれ所定のインピーダンス特性を測定する。このとき、測定に好適な測定周波数が判明していない場合は、周波数を変化させながら上記インピーダンス特性の測定を行って、保存剤添付品と保存剤無添付品とで測定値の差が大きい周波数を確認し、これに基づいて測定周波数を設定することが好ましい。そして該測定周波数における保存剤添付品および／または保存剤無添付品の前記インピーダンス特性測定値の許容範囲を、制御部４のメモリに記憶させる。
この後、保存剤の有無が未知の被験包装食品６を搬送装置２に供給し、該被験包装食品６が検出部１を通過するときに測定される前記インピーダンス特性測定値を前記許容範囲と比較することにより、被験包装食品６中の保存剤の有無の判定を行う。 In order to detect the preservative using the preservative detection apparatus of the present embodiment, the prepackaged food with the preservative (preservative attached) and the prepackaged food without the preservative (preservative not attached) For each product, a predetermined impedance characteristic is measured. At this time, when the measurement frequency suitable for the measurement is not known, the impedance characteristic is measured while changing the frequency, and the frequency with a large difference in the measured value between the preservative-free product and the preservative-free product is large. It is preferable to set the measurement frequency based on this. Then, the allowable range of the impedance characteristic measurement value of the preservative-attached product and / or the preservative-free product at the measurement frequency is stored in the memory of the control unit 4.
Thereafter, the test packaged food 6 with or without the preservative is supplied to the transport device 2, and the impedance characteristic measurement value measured when the test packaged food 6 passes the detection unit 1 is compared with the allowable range. By doing this, the presence or absence of the preservative in the test packaged food 6 is determined.

保存剤の検知を行う際に、電磁波発信極板１２ａ、１２ｂから発信される電磁波の周波数（測定周波数）としては、２ｋＨｚ以上５ＭＨｚ以下の範囲から選択することが好ましい。２ｋＨｚ未満では測定値の変動が大きくて好ましくない。一方、５ＭＨｚを越える周波数の場合には、検出精度が低下するので好ましくない。
なお、インピーダンスＺ値の位相角の値は、５ＭＨｚを越える周波数帯域においても保存剤の有無によってある程度の差を示すが、周波数が高くなるに従って、その差は次第に小さくなる。 When detecting the preservative, the frequency (measurement frequency) of the electromagnetic wave transmitted from the electromagnetic wave transmission electrode plates 12a and 12b is preferably selected from the range of 2 kHz to 5 MHz. If it is less than 2 kHz, the fluctuation of the measured value is large, which is not preferable. On the other hand, a frequency exceeding 5 MHz is not preferable because the detection accuracy is lowered.
The phase angle value of the impedance Z value shows a certain difference depending on the presence or absence of a preservative even in a frequency band exceeding 5 MHz, but the difference gradually decreases as the frequency increases.

前記インピーダンス特性として（１）インピーダンスＺ値の位相角を測定する場合、該インピーダンスＺ値の位相角は、計測器３に付属の計測ソフト等、既知の計測手段を用いて測定することができる。具体的には、計測器３（例えば、前記ＬＣＲハイテスター３５３２−５０）の接地アダプター付電源コードを電源につなぎ、接地アダプター接地端子を接地アースし、４本の測定ケーブルを電磁波送信端子（Ｈｃｕｒ端子およびＨｐｏｔ端子）３１、３２および電磁波受信端子（Ｌｃｕｒ端子およびＬｐｏｔ端子）３３、３４に接続する。しかる後、（Ｈｃｕｒ端子およびＨｐｏｔ端子）３１、３２に接続した測定ケーブルを電磁波発信極板１２ａ、１２ｂに接続し、電磁波受信端子（Ｌｃｕｒ端子およびＬｐｏｔ端子）３３、３４に接続した測定ケーブルを電磁波受信極板１３に接続する。また、計測器３のＧｕａｒｄ端子を接地アースする。
この状態で、計測器３の電源をスイッチをｏｎし、初期画面にて、計測項目として、位相角（θ）をｉｎｐｕｔし、測定速度、電圧レベル、測定周波数をｉｎｐｕｔし、検出部１の電磁波発信極板１２ａ、１２ｂおよび電磁波受信極板１３上に被測定物である包装食品が載置された状態でＥＸＩＴを押すことにより、測定できる。
本実施形態の装置を用いてインピーダンスＺ値の位相角を測定すると、後述の参考例にも示されるように、５０ｋＨｚを超える周波数帯域において、保存剤添付品と保存剤無添付品との測定値の差が大きくなる。したがって、高い精度で保存剤の検出を安定して行うことができる。好ましい測定周波数は５０ｋＨｚ〜５ＭＨｚであり、より好ましい測定周波数は１００ｋＨｚ〜１ＭＨｚである。 As the impedance characteristic, (1) when measuring the phase angle of the impedance Z value, the phase angle of the impedance Z value can be measured using a known measuring means such as measurement software attached to the measuring instrument 3. Specifically, the power cord with the ground adapter of the measuring instrument 3 (for example, the LCR high tester 3532-50) is connected to the power source, the ground adapter ground terminal is grounded, and the four measurement cables are connected to the electromagnetic wave transmission terminal (Hcur). Terminal and Hpot terminal) 31, 32 and electromagnetic wave receiving terminal (Lcur terminal and Lpot terminal) 33, 34. Thereafter, the measurement cables connected to (Hcur terminal and Hpot terminal) 31, 32 are connected to electromagnetic wave transmitting electrode plates 12a, 12b, and the measurement cables connected to electromagnetic wave receiving terminals (Lcur terminal and Lpot terminal) 33, 34 are electromagnetic waves. Connect to the receiving electrode plate 13. In addition, the Guard terminal of the measuring instrument 3 is grounded.
In this state, the power source of the measuring instrument 3 is turned on, the phase angle (θ) is input as the measurement item on the initial screen, the measurement speed, the voltage level, and the measurement frequency are input, and the electromagnetic wave of the detection unit 1 is input. The measurement can be performed by pressing EXIT in a state where the packaged food as the object to be measured is placed on the transmission electrode plates 12 a and 12 b and the electromagnetic wave reception electrode plate 13.
When the phase angle of the impedance Z value is measured using the apparatus of the present embodiment, as shown in a reference example to be described later, in the frequency band exceeding 50 kHz, the measured value of the preservative-attached product and the preservative-free product The difference becomes larger. Therefore, the preservative can be stably detected with high accuracy. A preferable measurement frequency is 50 kHz to 5 MHz, and a more preferable measurement frequency is 100 kHz to 1 MHz.

前記インピーダンス特性として（２）等価直列回路モードにおける抵抗値Ｒｓ値を測定する場合、該等価直列回路モードにおける抵抗値Ｒｓ値は、計測器３に付属の計測ソフト等、既知の計測手段を用いて測定することができる。具体的には、前記（１）インピーダンスＺ値の位相角を測定する場合と同様に計測器３の配線を行って、計測器３の電源をスイッチをｏｎし、初期画面にて、計測項目として、抵抗値Ｒｓ値をｉｎｐｕｔし、測定速度、電圧レベル、測定周波数をｉｎｐｕｔし、検出部１の電磁波発信極板１２ａ、１２ｂおよび電磁波受信極板１３上に被測定物である包装食品が載置された状態でＥＸＩＴを押すことにより、測定できる。
本実施形態の装置を用いて等価直列回路モードにおける抵抗値Ｒｓ値を測定すると、後述の参考例にも示されるように、特に２ｋＨｚ〜２００ｋＨｚの周波数帯域で、保存剤無添付品に対して保存剤添付品の測定値が数倍以上の大きな差を得ることができる。また前記特許文献２に記載の従来法では検出に不適であった、２ｋＨｚ以上２０ｋＨｚ未満の周波数帯域においても、保存剤添付品と保存剤無添付品との測定値の大きな差が得られる。したがって、高い精度で保存剤の検出を安定して行うことができる。好ましい測定周波数は２ｋＨｚ以上２００ｋＨｚ以下であり、より好ましい測定周波数は５ｋＨｚ以上１００ｋＨｚ以下である。 When the resistance value Rs value in the equivalent series circuit mode is measured as the impedance characteristic (2), the resistance value Rs value in the equivalent series circuit mode is measured using a known measurement means such as measurement software attached to the measuring instrument 3. Can be measured. Specifically, wiring of the measuring instrument 3 is performed in the same manner as in the case of (1) measuring the phase angle of the impedance Z value, the power source of the measuring instrument 3 is turned on, and the measurement items are displayed on the initial screen. The resistance value Rs value is input, the measurement speed, the voltage level, and the measurement frequency are input, and the packaged food as the object to be measured is placed on the electromagnetic wave transmission electrode plates 12 a and 12 b and the electromagnetic wave reception electrode plate 13 of the detection unit 1. Measurement can be performed by pressing EXIT in the state of being performed.
When the resistance value Rs value in the equivalent series circuit mode is measured using the apparatus of this embodiment, as shown in a reference example to be described later, it is stored in the frequency band of 2 kHz to 200 kHz, particularly with no preservative attached. A large difference of several times or more in the measured value of the agent attachment can be obtained. Further, even in a frequency band of 2 kHz to less than 20 kHz, which is unsuitable for detection by the conventional method described in Patent Document 2, a large difference in measured values between the preservative-attached product and the preservative-free product is obtained. Therefore, the preservative can be stably detected with high accuracy. A preferable measurement frequency is 2 kHz or more and 200 kHz or less, and a more preferable measurement frequency is 5 kHz or more and 100 kHz or less.

前記インピーダンス特性として（３）等価直列回路モードにおける静電容量Ｃｓ値を測定する場合、該等価直列回路モードにおける静電容量Ｃｓ値は、計測器３に付属の計測ソフト等、既知の計測手段を用いて測定することができる。具体的には、前記（１）インピーダンスＺ値の位相角を測定する場合と同様に計測器３の配線を行って、計測器３の電源をスイッチをｏｎし、初期画面にて、計測項目として、静電容量Ｃｓ値をｉｎｐｕｔし、測定速度、電圧レベル、測定周波数をｉｎｐｕｔし、検出部１の電磁波発信極板１２ａ、１２ｂ、電磁波受信極板１３上に被測定物である包装食品が載置された状態でＥＸＩＴを押すことにより、測定できる。
インピーダンス特性として等価直列回路モードにおける静電容量Ｃｓ値を用いる場合、保存剤添付品と保存剤無添付品との測定値の良好な差を得るうえで、好ましい測定周波数は２ｋＨｚ以上、１ＭＨｚ以下であり、より好ましい測定周波数は１６ｋＨｚ以上、６００ｋＨｚ以下である。 When the capacitance Cs value in the equivalent series circuit mode is measured as the impedance characteristic (3), the capacitance Cs value in the equivalent series circuit mode is measured using a known measurement means such as measurement software attached to the measuring instrument 3. Can be measured. Specifically, wiring of the measuring instrument 3 is performed in the same manner as in the case of (1) measuring the phase angle of the impedance Z value, the power source of the measuring instrument 3 is turned on, and the measurement items are displayed on the initial screen. The capacitance Cs value is input, the measurement speed, the voltage level, and the measurement frequency are input, and the packaged food as the object to be measured is placed on the electromagnetic wave transmission electrode plates 12 a and 12 b and the electromagnetic wave reception electrode plate 13 of the detection unit 1. It can be measured by pressing EXIT in the placed state.
When the capacitance Cs value in the equivalent series circuit mode is used as the impedance characteristic, a preferable measurement frequency is 2 kHz or more and 1 MHz or less in order to obtain a good difference in measured values between the preservative-attached product and the preservative-free product. Yes, and a more preferable measurement frequency is 16 kHz or more and 600 kHz or less.

本実施形態によれば、インピーダンス特性として、インピーダンスＺ値の位相角、等価直列回路モードにおける抵抗値Ｒｓ値、等価直列回路モードにおける静電容量Ｃｓ値から選ばれる１以上を用いることにより、保存剤が添付されていない包装食品（保存剤無添付品）と、保存剤が添付された包装食品（保存剤添付品）とで、測定値の大きな差を得ることができるため、高い検出精度で、安定して保存剤の有無を検出することができる。
また、前記従来方法では、測定周波数が２０ｋＨｚ未満では計測感度が低下し、４０ｋＨｚを超えると電磁波の漏洩、ノイズの侵入が多くなるとして、好適な測定周波数帯域が２０〜４０ｋＨｚと狭い範囲であったが、本実施形態によれば、２ｋＨｚ以上５ＭＨｚ以下の広い周波数帯域で、高精度の検出を行うことができる。このことには、本実施形態における電磁波発信極板１２ａ、１２ｂおよび電磁波受信極板１３の形状と、インピーダンス特性として、インピーダンスＺ値の位相角、等価直列回路モードにおける抵抗値Ｒｓ値、等価直列回路モードにおける静電容量Ｃｓ値から選ばれる１以上を用いることが大きく寄与していると考えられる。
また本実施形態の検出装置においては、該電磁波発信極板１２ａ、１２ｂのＺ方向の高さＨ２を変化させることにより、所定の周波数における検出感度を選択的に向上できるという利点も得られる。 According to the present embodiment, as the impedance characteristic, by using one or more selected from the phase angle of the impedance Z value, the resistance value Rs value in the equivalent series circuit mode, and the capacitance Cs value in the equivalent series circuit mode, the preservative is used. Because a large difference in measured values can be obtained between packaged foods that are not attached (packaged products without preservatives) and packaged foods with preservatives (packaged with preservatives), with high detection accuracy, The presence or absence of a preservative can be detected stably.
In the conventional method, if the measurement frequency is less than 20 kHz, the measurement sensitivity is lowered, and if it exceeds 40 kHz, leakage of electromagnetic waves and intrusion of noise increase, so that a suitable measurement frequency band is a narrow range of 20 to 40 kHz. However, according to the present embodiment, highly accurate detection can be performed in a wide frequency band of 2 kHz or more and 5 MHz or less. This includes the shapes of the electromagnetic wave transmitting electrode plates 12a and 12b and the electromagnetic wave receiving electrode plate 13 in the present embodiment, the impedance characteristics, the phase angle of the impedance Z value, the resistance value Rs value in the equivalent series circuit mode, and the equivalent series circuit. It is considered that using one or more selected from the capacitance Cs value in the mode greatly contributes.
Further, in the detection device of this embodiment, there is an advantage that the detection sensitivity at a predetermined frequency can be selectively improved by changing the height H2 of the electromagnetic wave transmission electrode plates 12a and 12b in the Z direction.

なお、上記実施形態では、第２の板部１２Ｂは、Ｘ方向における第１の板部１２Ａの両端部のうち、電磁波受信極板１３の側面と近接する方の端部に設けられており、第２の板部１２Ｂと電磁波受信極板１３との距離はＷ１であるが、第２の板部１２Ｂを、Ｘ方向における第１の板部１２Ａの両端部のうち、電磁波受信極板１３の側面から遠い方の端部に設け、第２の板部１２Ｂと電磁波受信極板１３との距離が略（Ｗ１＋Ｗ２）である構成としてもよい。 In the above embodiment, the second plate portion 12B is provided at the end portion closer to the side surface of the electromagnetic wave receiving electrode plate 13 among the both end portions of the first plate portion 12A in the X direction. The distance between the second plate portion 12B and the electromagnetic wave receiving electrode plate 13 is W1, but the second plate portion 12B is connected to the electromagnetic wave receiving electrode plate 13 of both end portions of the first plate portion 12A in the X direction. It is good also as a structure which is provided in the edge part far from a side surface, and the distance of the 2nd board part 12B and the electromagnetic wave receiving electrode plate 13 is substantially (W1 + W2).

以下に実施例を用いて本発明をさらに詳しく説明するが、本発明はこれら実施例に限定されるものではない。
（参考例１）
インピーダンス特性として（１）インピーダンスＺ値の位相角を用いる方法で保存剤の検知を行った。
計測器３としてＬＣＲハイテスター３５３２−５０（日置電機（株）製）を用いた。第１および第２の電磁波発信極板１２ａ、１２ｂはアルミ製で、Ｘ方向の幅Ｗ２が１５ｍｍ、Ｚ方向の高さＨ２が２５ｍｍ、Ｙ方向の長さが２２０ｍｍのものを用いた。第１および第２の電磁波発信極板１２ａ、１２ｂは、第２の板部１２Ｂが、Ｘ方向における第１の板部１２Ａの両端部のうち、電磁波受信極板１３の側面と近接する方の端部に位置するように設けた。
電磁波受信極板１３はアルミ製で、幅Ｗ３が９ｍｍ、Ｚ方向の高さＨ３が９ｍｍ、Ｙ方向の長さが２２０ｍｍのものを用いた。Ｘ方向における第１および第２の電磁波発信極板１２ａ、１２ｂと電磁波受信極板１３との間隔Ｗ１は１５ｍｍとした。
第１の電磁波遮蔽板１１ａおよび第２の電磁波遮蔽板１１ｂはステンレス板で構成し、基板１４の枠板１５および側板１６はアクリル樹脂製基板を用いた。
検出部１内の搬送コンベアー２１上に何も載置されていないことを確認した後、計測器３の電磁波送信端子（Ｈｃｕｒ端子およびＨｐｏｔ端子）３１、３２を、リード線８１、８２を介して電磁波発信極板１２ａ、１２ｂにそれぞれ接続し、計測器３の電磁波受信端子（Ｌｃｕｒ端子およびＬｐｏｔ端子）３３、３４をリード線９１、９２を介して電磁波受信極板１３に接続した。
包装食品として、ピロー包装フルーツ・パウンド（香月堂社製）を用い、保存剤としてアンチモールドマイルド１０（登録商標、フロイント産業社製、使用されているエタノール水溶液の濃度；９２質量％）を用いた。
インピーダンスＺ値の位相角の測定は、ＬＣＲハイテスター３５３２−５０のＲＳ２３２Ｃ端子を、コンピュータ（ＦＭＶ−ｂｉｂｌｏ−ＮＢ７０Ｅ、富士電機社製）のＲＳ２３２Ｃ端子に接続し、ＬＣＲハイテスター３５３２−５０に付属の計測ソフトを用いて行った。 Hereinafter, the present invention will be described in more detail using examples, but the present invention is not limited to these examples.
(Reference Example 1)
The preservative was detected by a method using (1) the phase angle of the impedance Z value as the impedance characteristic.
As the measuring instrument 3, an LCR high tester 3532-50 (manufactured by Hioki Electric Co., Ltd.) was used. The first and second electromagnetic wave transmitting electrode plates 12a and 12b are made of aluminum, and have a width W2 in the X direction of 15 mm, a height H2 in the Z direction of 25 mm, and a length in the Y direction of 220 mm. The first and second electromagnetic wave transmitting electrode plates 12a and 12b are configured such that the second plate portion 12B is closer to the side surface of the electromagnetic wave receiving electrode plate 13 out of both end portions of the first plate portion 12A in the X direction. It provided so that it might be located in an edge part.
The electromagnetic wave receiving electrode plate 13 was made of aluminum, had a width W3 of 9 mm, a height H3 in the Z direction of 9 mm, and a length in the Y direction of 220 mm. The interval W1 between the first and second electromagnetic wave transmission electrode plates 12a and 12b and the electromagnetic wave reception electrode plate 13 in the X direction was set to 15 mm.
The first electromagnetic wave shielding plate 11a and the second electromagnetic wave shielding plate 11b are made of stainless steel plates, and the frame plate 15 and the side plate 16 of the substrate 14 are acrylic resin substrates.
After confirming that nothing is placed on the conveyor 21 in the detection unit 1, the electromagnetic wave transmission terminals (Hcur terminal and Hpot terminal) 31, 32 of the measuring instrument 3 are connected via lead wires 81, 82. The electromagnetic wave transmitting electrode plates 12 a and 12 b were connected to each other, and the electromagnetic wave receiving terminals (Lcur terminal and Lpot terminal) 33 and 34 of the measuring instrument 3 were connected to the electromagnetic wave receiving electrode plate 13 via lead wires 91 and 92.
Uses pillow-wrapped fruit compound (Kogetsudo Co., Ltd.) as the packaged food, and Anti-Mold Mild 10 (registered trademark, Freund Sangyo Co., Ltd. used ethanol solution concentration: 92% by mass) as the preservative It was.
The phase angle of the impedance Z value is measured by connecting the RS232C terminal of the LCR high tester 3532-50 to the RS232C terminal of a computer (FMV-biblo-NB70E, manufactured by Fuji Electric Co., Ltd.) and attaching to the LCR high tester 3532-50. The measurement software was used.

まず、保存剤を添付した包装食品を、第１および第２の電磁波発信極板１２ａ、１２ｂ上、および電磁波受信極板１３上にまたがるように載置し、２ｋＨｚから１ＭＨｚまで、２ｋＨｚ間隔で電磁波を発信させてインピーダンスＺ値の位相角を測定した。その結果を図３のグラフに実線で示す。
次いで、保存剤を添付していない包装食品について、同様にしてインピーダンスＺ値の位相角を測定した。その結果を図３のグラフに破線で示す。
図３のグラフにおいて、横軸は周波数を示し、縦軸は位相角を示している。 First, the packaged food attached with the preservative is placed so as to straddle the first and second electromagnetic wave transmitting electrode plates 12a and 12b and the electromagnetic wave receiving electrode plate 13, and electromagnetic waves are emitted at intervals of 2 kHz from 2 kHz to 1 MHz. And the phase angle of the impedance Z value was measured. The result is shown by a solid line in the graph of FIG.
Next, the phase angle of the impedance Z value was measured in the same manner for the packaged food without the preservative. The result is shown by a broken line in the graph of FIG.
In the graph of FIG. 3, the horizontal axis indicates the frequency, and the vertical axis indicates the phase angle.

図３の結果より、周波数４０ｋＨｚ付近では、保存剤の有無によって位相角の測定値に差は無いが、周波数５０ｋＨｚ以上の範囲において、保存剤の有無によって位相角の測定値に明らかな差があり、特に３５０ｋＨｚ〜４００ｋＨｚの範囲で該測定値の差が大きかった。 From the results shown in FIG. 3, there is no difference in the measured value of the phase angle depending on the presence or absence of the preservative in the vicinity of the frequency of 40 kHz, but there is a clear difference in the measured value of the phase angle depending on the presence or absence of the preservative in the frequency range of 50 kHz or more. In particular, the difference between the measured values was large in the range of 350 kHz to 400 kHz.

（実施例１）
参考例１の結果より、インピーダンスＺ値の位相角の測定周波数を３６５ｋＨｚに設定して、保存剤の検出を行った。測定装置は参考例１と同じ構成とした。包装食品および保存剤は参考例１と同じものを用いた。
包装食品中に保存剤を添付した保存剤添付品４０点を製造し、これらを１つずつ、検出部１内を搬送させながら、測定装置３０によりインピーダンスＺ値の位相角を測定した。そして、測定されたインピーダンスＺ値の位相角の値の平均値と標準偏差値を求めた。
同様に、包装食品中に保存剤を添付しない状態の保存剤無添付品４０点についてインピーダンスＺ値の位相角を測定し、該測定値の平均値と標準偏差値を測定した。
この結果を下記表１に示す。 Example 1
From the result of Reference Example 1, the measurement frequency of the phase angle of the impedance Z value was set to 365 kHz, and the preservative was detected. The measurement apparatus had the same configuration as in Reference Example 1. The packaged food and the preservative were the same as in Reference Example 1.
Forty preservative accessories with preservatives attached to the packaged food were manufactured, and the phase angle of the impedance Z value was measured by the measuring device 30 while transporting these one by one through the detection unit 1. Then, an average value and a standard deviation value of the phase angle values of the measured impedance Z values were obtained.
Similarly, the phase angle of the impedance Z value was measured with respect to 40 preservative-free products with no preservative attached to the packaged food, and the average value and standard deviation value of the measured values were measured.
The results are shown in Table 1 below.

表１に示される、保存剤の有無によるインピーダンスＺ値の位相角の差について有意差検定を行った結果、信頼限界９９％で有意な差であることが確認された。 As a result of performing a significant difference test on the phase angle difference of the impedance Z value depending on the presence or absence of the preservative shown in Table 1, it was confirmed that the difference was significant with a confidence limit of 99%.

（参考例２）
インピーダンス特性として、（２）等価直列回路モードにおける抵抗値Ｒｓ値を用いる方法で保存剤の検知を行った。
参考例１において、第１および第２の電磁波発信極板１２ａ、１２ｂにおける第２の板部１２Ｂの位置を、Ｘ方向における第１の板部１２Ａの両端部のうち、電磁波受信極板１３の側面から遠い方の端部に変更した。また、Ｘ方向における第１および第２の電磁波発信極板１２ａ、１２ｂと電磁波受信極板１３との間隔Ｗ１を７ｍｍに変更した。
それ以外は同じ装置構成とした。
包装食品として、ピロー包装ミニ・バームクーヘン（香月堂社製）を用い、保存剤としてアンチモールドマイルド２０（登録商標、フロイント産業社製、使用されているエタノール水溶液の濃度；９２質量％）を用いた。等価直列回路モードにおける抵抗値Ｒｓ値の測定は、ＬＣＲハイテスター３５３２−５０のＲＳ２３２Ｃ端子を、コンピュータ（ＦＭＶ−ｂｉｂｌｏ−ＮＢ７０Ｅ、富士電機社製）のＲＳ２３２Ｃ端子に接続し、ＬＣＲハイテスター３５３２−５０に付属の計測ソフトを用いて行った。 (Reference Example 2)
As the impedance characteristics, (2) the preservative was detected by a method using the resistance value Rs value in the equivalent series circuit mode.
In Reference Example 1, the position of the second plate portion 12B in the first and second electromagnetic wave transmission electrode plates 12a and 12b is set to the position of the electromagnetic wave reception electrode plate 13 out of both end portions of the first plate portion 12A in the X direction. Changed to the end far from the side. Further, the interval W1 between the first and second electromagnetic wave transmitting electrode plates 12a and 12b and the electromagnetic wave receiving electrode plate 13 in the X direction was changed to 7 mm.
Other than that, the apparatus configuration was the same.
Pillow-wrapped mini-Baumkuchen (manufactured by Kogetsudo) is used as the packaged food, and Antimold Mild 20 (registered trademark, Freund Sangyo Co., Ltd., used aqueous ethanol concentration: 92% by mass) is used as the preservative. It was. In the equivalent series circuit mode, the resistance value Rs is measured by connecting the RS232C terminal of the LCR high tester 3532-50 to the RS232C terminal of a computer (FMV-biblo-NB70E, manufactured by Fuji Electric Co., Ltd.), and the LCR high tester 3532-50. The measurement software attached to was used.

まず、保存剤を添付した包装食品を、第１および第２の電磁波発信極板１２ａ、１２ｂ上、および電磁波受信極板１３上にまたがるように載置し、２ｋＨｚから５００ｋＨｚまで、２００Ｈｚ間隔で電磁波を発信させて等価直列回路モードにおける抵抗値Ｒｓ値を測定した。
次いで、保存剤を添付していない包装食品について、同様にして等価直列回路モードにおける抵抗値Ｒｓ値を測定した。
保存剤を添付した包装食品における前記Ｒｓ値（ＲｓＡ値）と、保存剤を添付していない包装食品における前記Ｒｓ値（ＲｓＯ値）との比（ＲｓＡ値／ＲｓＯ値）を、各発信周波数毎に求めた。その結果を図４のグラフに実線で示す。
図４のグラフにおいて、横軸は周波数を示し、縦軸はＲｓＡ値／ＲｓＯ値の値を示している。 First, the packaged food attached with a preservative is placed so as to straddle the first and second electromagnetic wave transmission electrode plates 12a and 12b and the electromagnetic wave reception electrode plate 13, and electromagnetic waves are emitted at intervals of 200 Hz from 2 kHz to 500 kHz. And the resistance value Rs value in the equivalent series circuit mode was measured.
Next, the resistance value Rs value in the equivalent series circuit mode was measured in the same manner for the packaged food without the preservative.
The ratio (RsA value / RsO value) of the Rs value (RsA value) in the packaged food with a preservative and the Rs value (RsO value) in the packaged food without the preservative is determined for each transmission frequency. Asked. The result is shown by a solid line in the graph of FIG.
In the graph of FIG. 4, the horizontal axis indicates the frequency, and the vertical axis indicates the RsA value / RsO value.

図４の結果より、周波数５０ｋＨｚ以下の範囲ではＲｓＡ値／ＲｓＯ値が１より大きく、特に２０ｋＨｚ以下の範囲でより大きい値となった。９０ｋＨｚ以上の範囲ではＲｓＡ値／ＲｓＯ値が１に近くなった。
なお、２ｋＨｚ未満ではノイズによる測定値の乱れが大きく、ノイズの点からは５ｋＨｚ以上が好ましい。 From the results shown in FIG. 4, the RsA value / RsO value was larger than 1 in the frequency range of 50 kHz or less, and particularly larger in the range of 20 kHz or less. The RsA value / RsO value was close to 1 in the range of 90 kHz or higher.
If the frequency is less than 2 kHz, the measurement value is greatly disturbed by noise. From the viewpoint of noise, 5 kHz or more is preferable.

（実施例２）
参考例２の結果より、等価直列回路モードにおける抵抗値Ｒｓ値の測定周波数を５ｋＨｚに設定して、保存剤の検出を行った。測定装置は参考例２と同じ構成とした。包装食品および保存剤は参考例２と同じものを用いた。
包装食品中に保存剤を添付した保存剤添付品４０点を製造し、これらを１つずつ、検出部１内を搬送させながら、測定装置３０により等価直列回路モードにおける抵抗値Ｒｓ値を測定した。そして、測定された等価直列回路モードにおける抵抗値Ｒｓ値の平均値と標準偏差値を求めた。
同様に、包装食品中に保存剤を添付しない状態の保存剤無添付品４０点について等価直列回路モードにおける抵抗値Ｒｓ値を測定し、該測定値の平均値と標準偏差値を測定した。
この結果を下記表２に示す。 (Example 2)
From the result of Reference Example 2, the measurement frequency of the resistance value Rs value in the equivalent series circuit mode was set to 5 kHz, and the preservative was detected. The measurement apparatus had the same configuration as in Reference Example 2. The packaged food and the preservative were the same as in Reference Example 2.
40 preservative accessories with preservatives attached to the packaged food were manufactured, and the resistance value Rs value in the equivalent series circuit mode was measured by the measuring device 30 while transporting these one by one through the detection unit 1. . And the average value and standard deviation value of resistance value Rs value in the measured equivalent series circuit mode were calculated | required.
Similarly, the resistance value Rs value in the equivalent series circuit mode was measured for 40 preservative-free products with no preservative attached to the packaged food, and the average value and the standard deviation value of the measured values were measured.
The results are shown in Table 2 below.

表２に示される、保存剤の有無による等価直列回路モードにおける抵抗値Ｒｓ値の差について有意差検定を行った結果、信頼限界９９％で有意な差であることが確認された。 As a result of conducting a significant difference test on the difference in the resistance value Rs value in the equivalent series circuit mode depending on the presence or absence of the preservative shown in Table 2, it was confirmed that the difference was significant with a 99% confidence limit.

（参考例３）
インピーダンス特性として、（２）等価直列回路モードにおける抵抗値Ｒｓ値を用いる方法で保存剤の検知を行った。
参考例１において、第１および第２の電磁波発信極板１２ａ、１２ｂのＺ方向の高さＨ２を１ｍｍに変更し、電磁波受信極板１３のＺ方向の高さＨ３を１ｍｍに変更し、かつＸ方向における第１および第２の電磁波発信極板１２ａ、１２ｂと電磁波受信極板１３との間隔Ｗ１を７ｍｍに変更した以外は同じ装置構成とした。本例において、第１および第２の電磁波発信極板１２ａ、１２ｂは第１の板部１２Ａ（厚さ１ｍｍ）のみからなり、第２の板部１２Ｂは有していない。
包装食品は参考例２と同じものを用いた。 (Reference Example 3)
As the impedance characteristics, (2) the preservative was detected by a method using the resistance value Rs value in the equivalent series circuit mode.
In Reference Example 1, the height H2 in the Z direction of the first and second electromagnetic wave transmitting electrode plates 12a, 12b is changed to 1 mm, the height H3 in the Z direction of the electromagnetic wave receiving electrode plate 13 is changed to 1 mm, and The apparatus configuration was the same except that the interval W1 between the first and second electromagnetic wave transmitting electrode plates 12a and 12b and the electromagnetic wave receiving electrode plate 13 in the X direction was changed to 7 mm. In this example, the 1st and 2nd electromagnetic wave transmission electrode plates 12a and 12b consist only of the 1st board part 12A (thickness 1mm), and do not have the 2nd board part 12B.
The same packaged food as in Reference Example 2 was used.

まず、保存剤を添付した包装食品、および保存剤を添付していない包装食品それぞれについて、参考例２と同様にして、２ｋＨｚから５００ｋＨｚまで、２００Ｈｚ間隔で電磁波を発信させて等価直列回路モードにおける抵抗値Ｒｓ値を測定した。
保存剤を添付した包装食品における前記Ｒｓ値（ＲｓＡ値）と、保存剤を添付していない包装食品における前記Ｒｓ値（ＲｓＯ値）との比（ＲｓＡ値／ＲｓＯ値）を、各発信周波数毎に求めた。その結果を図５のグラフに実線で示す。
図５のグラフにおいて、横軸は周波数を示し、縦軸はＲｓＡ値／ＲｓＯ値の値を示している。 First, with respect to each of the packaged food with the preservative and the packaged food without the preservative, the resistance in the equivalent series circuit mode is generated by transmitting electromagnetic waves at intervals of 200 Hz from 2 kHz to 500 kHz in the same manner as in Reference Example 2. The value Rs value was measured.
The ratio (RsA value / RsO value) of the Rs value (RsA value) in the packaged food with a preservative and the Rs value (RsO value) in the packaged food without the preservative is determined for each transmission frequency. Asked. The result is shown by a solid line in the graph of FIG.
In the graph of FIG. 5, the horizontal axis indicates the frequency, and the vertical axis indicates the value of RsA value / RsO value.

図５の結果より、周波数２〜２５０ｋＨｚの範囲においてＲｓＡ値／ＲｓＯ値が１より大きく、特に２〜１００ｋＨｚの範囲でより大きい値となった。３００ｋＨｚ以上の範囲ではＲｓＡ値／ＲｓＯ値が１に近くなった。
また、ＲｓＡ値／ＲｓＯ値は２０ｋＨｚ付近で４．４５を示し、４ｋＨｚ付近でも３．３６と高い値であった。
なお、２ｋＨｚ未満ではノイズによる測定値の乱れが大きかった。 From the results of FIG. 5, the RsA value / RsO value was larger than 1 in the frequency range of 2 to 250 kHz, and particularly larger in the range of 2 to 100 kHz. In the range of 300 kHz or higher, the RsA value / RsO value was close to 1.
The RsA value / RsO value was 4.45 at around 20 kHz, and was a high value of 3.36 at around 4 kHz.
When the frequency was less than 2 kHz, the measurement value was greatly disturbed by noise.

また、参考例２の結果（図４）と参考例３の結果（図５）とを比べると、参考例２（図４）では、ＲｓＡ値／ＲｓＯ値の値が、２ｋＨｚで９．８２、１０ｋＨｚで８．０、２０ｋＨｚで６．０と高い値を示しており、特に低周波数帯域でのＲｓＡ値／ＲｓＯ値が大きい値を示している。このことから、電磁波発信極板１２ａ、１２ｂの形状を断面Ｌ字状としてH３よりもH２を大きくすることによって、等価直列モードにおける抵抗値Ｒｓ値により包装食品中の保存剤の有無を検出する方法において、所定の周波数帯域における検出精度を選択的に向上できることがわかる。 Further, when the result of Reference Example 2 (FIG. 4) and the result of Reference Example 3 (FIG. 5) are compared, in Reference Example 2 (FIG. 4), the RsA value / RsO value is 9.82 at 2 kHz. The values are as high as 8.0 at 10 kHz and 6.0 at 20 kHz. Particularly, the RsA value / RsO value in the low frequency band is large. From this, the method of detecting the presence or absence of a preservative in the packaged food by the resistance value Rs value in the equivalent series mode by making the shape of the electromagnetic wave transmission electrode plates 12a, 12b L-shaped and making H2 larger than H3 It can be seen that the detection accuracy in a predetermined frequency band can be selectively improved.

（参考例４）
インピーダンス特性として、（３）等価直列回路モードにおける静電容量Ｃｓ値を用いる方法で保存剤の検知を行った。
参考例１において、Ｘ方向における第１、および第２の電磁波発信極板１２ａ，１２ｂと電磁波受信極板１３との間隙Ｗ１を４ｍｍに変更した以外は同じ装置構成とした。
包装食品は参考例１と同じものを用いた。
等価直列モードとしての静電容量Ｃｓ値の測定は、インピーダンスＺ値の位相角の測定は、ＬＣＲハイテスター３５３２−５０のＲＳ２３２Ｃ端子を、コンピュータ（ＦＭＶ−ｂｉｂｌｏ−ＮＢ７０Ｅ、富士電機社製）のＲＳ２３２Ｃ端子に接続し、ＬＣＲハイテスター３５３２−５０に付属の計測ソフトを用いて行った。 (Reference Example 4)
As the impedance characteristic, (3) the preservative was detected by a method using the capacitance Cs value in the equivalent series circuit mode.
In Reference Example 1, the same device configuration was used except that the gap W1 between the first and second electromagnetic wave transmitting electrode plates 12a and 12b and the electromagnetic wave receiving electrode plate 13 in the X direction was changed to 4 mm.
The same packaged food as in Reference Example 1 was used.
The capacitance Cs value as the equivalent series mode is measured. The phase angle of the impedance Z value is measured by connecting the RS232C terminal of the LCR high tester 3532-50 to the RS232C of a computer (FMV-biblo-NB70E, manufactured by Fuji Electric Co., Ltd.). It connected to the terminal and performed using the measurement software attached to LCR high tester 3532-50.

まず、保存剤を添付した包装食品を、第１および第２の電磁波発信極板１２ａ、１２ｂ上、および電磁波受信極板１３上にまたがるように載置し、２ｋＨｚから１ＭＨｚまで、２ｋＨｚ間隔で電磁波を発信させて等価直列回路モードにおける静電容量Ｃｓ値を測定した。
次いで、保存剤を添付していない包装食品について、同様にして等価直列回路モードにおける静電容量Ｃｓ値を測定した。
保存剤を添付した包装食品における前記Ｃｓ値（ＣｓＡ値）と、保存剤を添付していない包装食品における前記Ｃｓ値（ＣｓＯ値）との差（ＣｓＯ値−ＣｓＡ値）を、各発信周波数毎に求めた。その結果を図６のグラフに実線で示す。
図６のグラフにおいて、横軸は周波数を示し、縦軸はＣｓＯ値−ＣｓＡ値の値を示している。 First, the packaged food attached with the preservative is placed so as to straddle the first and second electromagnetic wave transmitting electrode plates 12a and 12b and the electromagnetic wave receiving electrode plate 13, and electromagnetic waves are emitted at intervals of 2 kHz from 2 kHz to 1 MHz. And the capacitance Cs value in the equivalent series circuit mode was measured.
Subsequently, the electrostatic capacity Cs value in the equivalent series circuit mode was measured in the same manner for the packaged food without the preservative.
The difference (CsO value-CsA value) between the Cs value (CsA value) in the packaged food with the preservative attached and the Cs value (CsO value) in the packaged food without the preservative is determined for each transmission frequency. Asked. The result is shown by a solid line in the graph of FIG.
In the graph of FIG. 6, the horizontal axis represents the frequency, and the vertical axis represents the value of CsO value−CsA value.

図６の結果より、周波数１８ｋＨｚ以上、６００ｋＨｚ以下の範囲では保存剤を添付していない包装食品におけるＣｓ値（ＣｓＯ値）と保存剤を添付した包装食品におけるＣｓ値（ＣｓＡ値）との差（ＣｓＯ値−ＣｓＡ値）の値が２．５ｐＦより大きく、特に６０ｋＨｚ〜２７０ｋＨｚの範囲でより大きい値となった。
特に（ＣｓＯ値−ＣｓＡ値）の値は１３０ｋＨｚ〜１４０ｋＨｚの範囲で３．１ｐＦと高い値であった。
この結果から、本例の装置により、等価直列回路モードにおける静電容量Ｃｓ値を用いて、包装食品中の保存剤有無を検出する際の最適周波数は、１３０ｋＨｚ〜１４０ｋＨｚの範囲であると判断される。 From the results shown in FIG. 6, the difference between the Cs value (CsO value) in the packaged food without the preservative and the Cs value (CsA value) in the packaged food with the preservative in the frequency range of 18 kHz to 600 kHz ( The value of (CsO value−CsA value) was larger than 2.5 pF, and particularly larger in the range of 60 kHz to 270 kHz.
In particular, the value of (CsO value−CsA value) was as high as 3.1 pF in the range of 130 kHz to 140 kHz.
From this result, it is determined by the apparatus of this example that the optimum frequency when detecting the presence or absence of the preservative in the packaged food using the capacitance Cs value in the equivalent series circuit mode is in the range of 130 kHz to 140 kHz. The

（実施例３）
参考例４の結果より、等価直列回路モードにおける静電容量Ｃｓ値の測定周波数を１４０ＫＨｚに設定して、保存剤の検出を行った。測定装置は参考例４と同じ構成とした。包装食品および保存剤は参考例４と同じものを用いた。
包装食品中に保存剤を添付した保存剤添付品４０点を製造し、これらを１つずつ、検出部１内を搬送させながら、測定装置３０により等価直列回路モードにおける静電容量Ｃｓ値を測定した。そして、測定された等価直列回路モードにおける静電容量Ｃｓ値の平均値と標準偏差値を求めた。
同様に、包装食品中に保存剤を添付しない状態の保存剤無添付品４０点について等価直列回路モードにおける静電容量Ｃｓ値を測定し、該測定値の平均値と標準偏差値を測定した。
この結果を下記表３に示す。 (Example 3)
From the result of Reference Example 4, the measurement frequency of the capacitance Cs value in the equivalent series circuit mode was set to 140 KHz, and the preservative was detected. The measurement apparatus had the same configuration as in Reference Example 4. The packaged food and the preservative were the same as in Reference Example 4.
40 preservative accessories with preservatives attached to the packaged food are manufactured, and the capacitance Cs value in the equivalent series circuit mode is measured by the measuring device 30 while transporting these one by one through the detection unit 1. did. Then, the average value and the standard deviation value of the capacitance Cs value in the measured equivalent series circuit mode were obtained.
Similarly, the capacitance Cs value in the equivalent series circuit mode was measured for 40 preservative-free products in a state where no preservative was attached to the packaged food, and the average value and the standard deviation value of the measured values were measured.
The results are shown in Table 3 below.

表３に示される、保存剤の有無による等価直列回路モードにおける静電容量Ｃｓ値の差について有意差検定を行った結果、信頼限界９９％で有意な差であることが確認された。 As a result of conducting a significant difference test on the difference in the capacitance Cs value in the equivalent series circuit mode depending on the presence or absence of the preservative shown in Table 3, it was confirmed that the difference was significant with a 99% confidence limit.

本発明にかかる検出装置の一実施形態を示す概略構成図である。It is a schematic block diagram which shows one Embodiment of the detection apparatus concerning this invention. 図１の装置の要部を示す斜視図である。It is a perspective view which shows the principal part of the apparatus of FIG. 本発明にかかる参考例の結果を示すグラフである。It is a graph which shows the result of the reference example concerning this invention. 本発明にかかる参考例の結果を示すグラフである。It is a graph which shows the result of the reference example concerning this invention. 本発明にかかる参考例の結果を示すグラフである。It is a graph which shows the result of the reference example concerning this invention. 本発明にかかる参考例の結果を示すグラフである。It is a graph which shows the result of the reference example concerning this invention.

Explanation of symbols

１：検出部
２：搬送装置
３：計測器
４：制御部
５：排除装置
６：包装食品
１２ａ、１２ｂ：電磁波発信極板
１２Ａ：第１の板部
１２Ｂ：第２の板部
１３：電磁波受信極板
３０：測定装置

1: Detection unit 2: Conveying device 3: Measuring device 4: Control unit 5: Exclusion device 6: Packaged food 12a, 12b: Electromagnetic wave transmission electrode plate 12A: First plate unit 12B: Second plate unit 13: Electromagnetic wave reception Electrode 30: Measuring device

Claims

A method for detecting the presence or absence of a preservative made of a nonmagnetic material attached to the packaged food by measuring the impedance characteristics of the packaged food,
One or more selected from the phase angle of the impedance Z value, the resistance value Rs value in the equivalent series circuit mode, and the capacitance Cs value in the equivalent series circuit mode are used as the impedance characteristics.

The preservative detection method according to claim 1, wherein the preservative contains an aqueous ethanol solution having an ethanol concentration of 20% by mass or more and 95% by mass or less.

A preservative detection device for detecting the presence or absence of a preservative made of a non-magnetic material attached to a packaged food,
A measuring device for measuring the impedance characteristics of the packaged food;
The preset allowable range of the impedance characteristic of the packaged food based on the measurement value of the impedance characteristic of the packaged food for which the presence or absence of the preservative is known is stored, and the measurement value of the impedance characteristic of the packaged food by the measurement device is stored A control unit that determines the presence or absence of preservatives in the packaged food compared to the allowable range,
The preservative detection device, wherein the impedance characteristic is one or more selected from a phase angle of an impedance Z value, a resistance value Rs value in an equivalent series circuit mode, and a capacitance Cs value in an equivalent series circuit mode.

The measuring device comprises two electromagnetic wave transmitting electrode plates arranged opposite to each other, and one electromagnetic wave receiving electrode plate provided between the two electromagnetic wave transmitting electrode plates,
The electromagnetic wave transmission electrode plate has an L-shaped cross section composed of a first plate portion parallel to a surface on which the packaged food is placed and a second plate portion perpendicular to the first plate portion. The preservative detection device according to claim 3.

The two electromagnetic wave transmission electrode plates have the same dimensions, and when the direction from one electromagnetic wave transmission electrode plate to the other electromagnetic wave transmission electrode plate is the X direction, the width (W2) of the electromagnetic wave transmission electrode plate in the X direction ) Is 1 mm or more and 50 mm or less, and the distance (W1) between the electromagnetic wave transmission electrode plate and the electromagnetic wave reception electrode plate in the X direction is 1 mm or more and 30 mm or less.

The height (H3) of the electromagnetic wave receiving electrode plate in the Z direction perpendicular to the surface on which the packaged food is placed is 0.5 mm or more, and the width (W3) of the electromagnetic wave receiving electrode plate in the X direction. The height (H2) of the electromagnetic wave transmitting electrode plate in the Z direction is 1 to 3 times the height (H3) of the electromagnetic wave receiving electrode plate in the Z direction. 5. The preservative detection device according to 5.

The preservative detection device according to any one of claims 3 to 6, wherein the frequency of the electromagnetic wave used for the measurement of the impedance characteristic is in a range of 2 kHz to 5 MHz.

A preservative detection device for detecting the presence or absence of a preservative made of a non-magnetic material attached to a packaged food,
A measuring device for measuring the impedance characteristics of the packaged food;
The preset allowable range of the impedance characteristic of the packaged food based on the measurement value of the impedance characteristic of the packaged food for which the presence or absence of the preservative is known is stored, and the measurement value of the impedance characteristic of the packaged food by the measurement device is stored A control unit that determines the presence or absence of preservatives in the packaged food compared to the allowable range,
The measuring device includes two electromagnetic wave transmitting electrode plates arranged opposite to each other, and one electromagnetic wave receiving electrode plate provided between the two electromagnetic wave transmitting electrode plates, The preservative is characterized by having an L-shaped cross section comprising a first plate portion parallel to the surface on which the packaged food is placed and a second plate portion perpendicular to the first plate portion. Detection device.