Method and apparatus for detecting pinholes in molds for manufacturing frozen desserts

Abstract

This invention provides a method for accurately detecting pinholes in molds used for manufacturing frozen desserts. [Solution] The pinhole detection method involves immersing a mold 10 for making frozen desserts, which has a containment section for containing a fluid and solidifies the fluid, in a brine solution 22 to which a fluorescent food coloring has been added, and detecting pinholes in the mold 10 for making frozen desserts.

Description

Technical Field

[0001] The present invention relates to a pinhole detection method and apparatus for a mold for manufacturing frozen confections.

Background Art

[0002] In an example of a frozen confection manufacturing apparatus, a plurality of molds for manufacturing frozen confections attached to a circulating device at regular intervals are filled with raw materials for frozen confections, immersed in a brine solution of a refrigerant at a certain depth, conveyed while being immersed, and the raw materials for frozen confections are frozen in the molds for manufacturing frozen confections to manufacture frozen confections.

[0003] As the usage period of the mold for manufacturing frozen confections becomes longer, pinholes may occur in joints (welded parts) and the like. When pinholes occur, the brine solution enters the mold for manufacturing frozen confections through the pinholes and mixes into the frozen confections in the mold for manufacturing frozen confections. Since the brine solution itself is harmless to the human body, there is no problem even if a person eats or drinks frozen confections mixed with the brine solution, but it is not preferable, so it is necessary to prevent the mixing.

[0004] Patent Documents 1 and 2 disclose a refrigerant detection method in which a fluorescent dye (e.g., food red) is added to a refrigerant used in a beer brewing process, and the presence or absence of refrigerant mixing is examined for a sample of the manufactured beer using a spectrophotometer (e.g., a spectrofluorometer) or HPLC (high performance liquid chromatography).

[0005] Patent Document 3 discloses that in a casting apparatus in which a refrigerant is pumped into a cooling passage formed inside a mold, in order to detect leakage of the refrigerant to the molding surface of the mold, a fluorescent agent is mixed into the refrigerant, a black light is irradiated onto the molding surface, the molding surface is imaged by an imaging device, and the presence or absence of cracks in the mold is detected based on the captured image.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

[0007] Patent documents 1 and 2 detect whether fluorescent dyes are present in food and beverage samples after manufacturing, so they cannot prevent brine contamination in food and beverages in the first place.

[0008] The pinhole detection disclosed in Patent Document 3 concerns pinholes between a cooling passage provided within the mold through which refrigerant is pumped and the mold molding surface, and is not applicable to detecting pinholes in the mold wall of a mold for making frozen desserts in which a cooling passage through which refrigerant is pumped is not formed within the mold wall.

[0009] In view of the above-mentioned problems, the object of the present invention is to provide a pinhole detection method and apparatus that can accurately detect pinholes in molds for manufacturing frozen desserts. [Means for solving the problem]

[0010] The present invention provides a method for detecting pinholes in molds used for making frozen desserts. A method for detecting pinholes in a mold for making frozen desserts, which has a containment section for containing a liquid and solidifies the liquid, The pinholes in the mold for making frozen desserts are detected while the mold is immersed in a brine solution to which a fluorescent food coloring has been added.

[0011] The pinhole detection device for the frozen dessert manufacturing model of the present invention is A pinhole detection device for a mold used to manufacture frozen desserts, which has a containment section for containing a liquid and solidifies the liquid, The pinholes in the mold for making frozen desserts are detected while the mold is immersed in a brine solution to which a fluorescent food coloring has been added. [Effects of the Invention]

[0012] According to the present invention, pinholes in a mold for making frozen desserts are detected by immersing the mold in a brine solution containing a fluorescent food coloring, that is, by utilizing the liquid pressure of the brine solution acting on the outer surface of the mold. As a result, if a pinhole exists in the mold, the brine solution containing the food coloring on the outer surface of the mold will seep through the pinhole into the inner container due to the liquid pressure. This allows for accurate detection of the presence or absence of pinholes.

[0013] In typical molds for making frozen desserts, the cylindrical wall and the bottom wall are joined to the lower edge of the cylindrical wall via the periphery of the bottom wall, forming a housing that opens upwards. In such molds, pinholes tend to develop at the joint as the period of use increases. When a mold for making frozen desserts is immersed in brine, the joint is located at the lower end of the mold and is subjected to sufficiently large liquid pressure from the brine. As a result, pinholes in the mold can be easily detected. [Brief explanation of the drawing]

[0014] [Figure 1] This is a schematic diagram of a basic embodiment of a method for detecting pinholes in molds used for manufacturing frozen desserts. [Figure 2] This is a schematic front view of the first application example of a frozen dessert manufacturing apparatus to which a pinhole detection method is applied. [Figure 3] This is a schematic right side view of the first application example. [Figure 4] This is an explanatory diagram illustrating the switching between the manufacturing cycle and the detection cycle in a second application example of a frozen dessert manufacturing apparatus that applies a pinhole detection method. [Figure 5]It is a front view of the main part of the third application example of an ice confectionery manufacturing apparatus to which a pinhole detection method is applied.

Embodiments for Carrying Out the Invention

[0015] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments. Needless to say, the present invention includes aspects in which some elements are changed, added, or deleted with respect to the embodiments within the scope of the gist.

[0016] (Basic Embodiment) FIG. 1 is a schematic diagram of a basic embodiment of a pinhole detection method for a mold 10 for manufacturing ice confectionery.

[0017] STEP1 is a step of preparing the mold 10 to be detected. This mold 10 is used, for example, in the manufacture of ice confectionery (e.g., ice candy). A plurality of molds 10 are coupled to the same connecting plate 12 at the upper end and arranged in a row to form a mold set 14. The mold 10 has a cylindrical wall and a bottom wall joined to the lower end periphery of the cylindrical wall through the peripheral portion of the bottom wall, forming an accommodating portion that opens upward.

[0018] In the example of FIG. 1, the cylindrical wall and the bottom wall are a cylindrical wall and a circular wall, respectively. The cylindrical wall may have an inverted frustum shape in a side view and an inner diameter that increases upward. The bottom wall may be square or rectangular in a plan view (top view). Typically, the peripheral edge of the bottom wall is joined to the peripheral edge of the lower end of the cylindrical wall by welding. As the usage period of the mold 10 becomes longer, the first pinhole is likely to occur from this joint portion.

[0019] A pair of circulating chains 16 is also a support device for a plurality of mold sets 14, is disposed on both longitudinal sides of the mold set 14, and is coupled to both ends of each mold set 14 by fasteners 18. As shown in FIG. 2 and the like described later, a plurality of mold sets 14 are attached to and supported by the circulating chain 16 at equal intervals in its extending direction.

[0020] It is preferable to clean the inner surface of mold 10 in STEP 1 to remove dust, foreign matter, etc.

[0021] STEP 2 is the immersion process. The storage tank 20 stores brine solution 22 at a predetermined level as the immersion section. In STEP 2, the mold 10 is immersed in the brine solution 22 to a depth where the opening at its upper end is not submerged. The brine solution 22 consists of a refrigerant to which a fluorescent food coloring, such as food dye, has been added. The food dye has been selected as a fluorescent coloring that is safe for human ingestion.

[0022] In STEP 3, the UV lamp 26 acts as an excitation light irradiation unit, irradiating UV light (excitation light) towards the upper opening of the mold 10 below, which serves as the excitation light irradiation unit for the fluorescent material. The UV light irradiates the entire inner surface of the housing section of the mold 10. The fluorescent material excited by the UV light emits visible light.

[0023] In STEP 3, the monochrome camera 28, acting as the imaging unit, also photographs the inside of the mold 10. If traces of food coloring 31 are present on the inner surface of the mold 10, the light incident on the monochrome camera 28 will include its fluorescence emission (visible light). The UV cut filter 30 is attached to the incident lens of the monochrome camera 28, and light with UV light cut out is incident on the monochrome camera 28. Although the monochrome camera 28 is superior to the color camera in terms of sensitivity, resolution, and low-light shooting, this does not preclude the use of a color camera instead of the monochrome camera 28.

[0024] The UV cut filter 30 cuts out light in the ultraviolet region (10-400 nm), and it is preferable that the cut filter cuts out not only UV light (ultraviolet light) but also visible light with a wavelength of 420 nm or less (particularly the violet component of visible light) (typically, a cut filter where the frequency at which the gain drops by 3 dB relative to the gain of the passband is 420 nm). The reason is as follows: In other words, a real UV lamp 26 emits not only UV light but also light that includes the violet component of visible light with a frequency adjacent to the UV light. On the other hand, the food coloring in the trace 31 emits fluorescence when it receives UV light as excitation light, and this fluorescence is the red component of visible light. Therefore, the violet component of visible light is reflected from the inner surface of the trace 31 and the surrounding mold 10. For this reason, the trace 31 of food coloring on the inner surface of the mold 10 appears reddish-purple, with a mixture of the red and violet components of visible light. The UV cut filter 30 is designed to cut not only UV light but also the purple component of visible light with a wavelength of 420 nm or less. This is to prevent the purple component of visible light reflected from the inner surface of the mold 10 (other than the trace 31) from entering the monochrome camera 28 as noise, thereby enabling the monochrome camera 28 to clearly detect the trace 31.

[0025] Furthermore, a bandpass filter or the like that selectively transmits only the wavelength of fluorescence emission as filter 30 can also be used. This allows for further reduction of noise wavelengths in addition to excitation light, thereby further improving the detection sensitivity of fluorescence emission.

[0026] In STEP 4, the image analysis device 32, which serves as both an image analysis unit and a determination unit, detects the presence or absence of traces of food coloring 31 on the inner surface of the mold 10 based on the image captured by the monochrome camera 28. Food coloring, which is a fluorescent food coloring, generally emits red fluorescence when exposed to ultraviolet light, which is the excitation light. Therefore, by detecting red wavelength light with the image analysis device 32, it is possible to determine whether the brine solution 22 has seeped into the inner surface of the mold 10.

[0027] As mentioned above, the UV-cut filter 30 enhances the visibility of the fluorescence to be detected by cutting out ultraviolet light that is reflected from the inner surface of the mold 10 and becomes noise light. The image analysis device 32 also serves as a determination unit that determines whether the brine solution 22 has seeped into the inner surface of the mold 10 based on the intensity and spread of the fluorescence emitted from the fluorescent food coloring. As a determination unit, the image analysis device 32 extracts red regions from the captured image where the power spectrum density of the red component is above the first threshold as traces 31, and determines that a pinhole has occurred if the size or area of ​​the extracted traces 31 is above the second threshold. The minimum size or area that can be analyzed by image analysis of the captured image depends on the resolution of the monochrome camera and the measurement environment, but is typically 4 mm. 2 (Minimum area)

[0028] In the pinhole detection method of the basic embodiment, even if the mold 10 is not part of the mold set 14, a standalone mold 10 can be used as the target for pinhole detection. In the basic embodiment, even if the mold 10 is not incorporated into the frozen dessert manufacturing apparatus 38a described later as part of the mold set 14, that is, the mold set 14 alone can be processed as the target for pinhole detection. Furthermore, instead of the brine solution 22, a solution obtained by adding a fluorescent dye to a liquid unrelated to the refrigerant (e.g., water) can be used. This solution may be at room temperature, or it may be a solution that has been cooled or heated from room temperature. For example, the temperature of the liquid may be set to the temperature at which the concentration and luminescence of the food coloring are at their maximum, or to the temperature at which the diameter of the pinhole expands due to the thermal expansion of the mold 10.

[0029] In the basic embodiment, the mold 10 is immersed in brine 22 while empty, but it may also be filled with a predetermined contents (e.g., a contents that prevents the trace 31 from spreading and becoming lighter in color, i.e., preventing the weakening of fluorescence) before being immersed in brine 22. However, immersing the mold 10 empty in brine 22 increases the pressure difference between the inside and outside of the mold 10, making it easier for the brine 22 to penetrate the inner surface of the mold 10 through pinholes.

[0030] Typical mold 10, as mentioned above, is made by welding the cylindrical part and the bottom wall together, and as the usage time of mold 10 increases, the first pinholes are likely to occur in the welded area. In the immersion process of STEP 2, the welded area penetrates deeply into the brine solution 22 in mold 10, and a sufficiently large liquid pressure acts from the outer side of mold 10. In this way, the penetration of the fluorescent dye from the outer side to the inner side of 10 is promoted by the pressure difference, making it easier to detect the first pinholes that occur.

[0031] In STEP 4, the detection of traces 31 by image analysis can identify an image region including the joint, and the detection of fluorescence emission of the dye can prioritize the identified image region over the unidentified image region. For example, the image analysis device 32 can identify an image region including the joint of the mold 10 from the image captured by the monochrome camera 28, and for the identified image region, it can focus on the identified image region and enlarge or increase the resolution to improve detection efficiency, reduce detection load, and shorten detection time by checking for the presence or absence of fluorescence emission of the fluorescent dye.

[0032] Note that the diagram of mold 10 in STEP 4 is a plan view (a view from above). This plan view assumes that the housing section of the mold has an inverted truncated cone cross section. In the plan view, the area between the two concentric circles corresponds to the inner surface of the cylindrical wall of mold 10, and the area inside the inner circle corresponds to the upper surface of the bottom wall of mold 10.

[0033] If the cylindrical wall of the mold 10 is cylindrical, placing the UV lamp 26 and monochrome camera 28 above the central axis of the mold 10 makes it difficult for UV light to reach the inner surface of the cylindrical wall or to image the inner surface. In that case, multiple UV lamps 26 and monochrome cameras 28 can be arranged above at different angles.

[0034] A specific example of the aforementioned specific image region, as shown in the figure of STEP 4, is the annular circumferential region that surrounds the inner circumference of the two concentric circles of mold 10 with a predetermined width. The joint between the cylindrical part and the bottom part of mold 10 is located within this annular circumferential region, and this joint is the area in mold 10 where pinholes are most likely to occur as it is used over time.

[0035] (Frozen dessert manufacturing equipment / 1st application example) Figures 2 and 3 are schematic front and right side views, respectively, of a frozen dessert manufacturing apparatus 38a (frozen dessert manufacturing apparatus of the first application example) equipped with a pinhole detection device. The frozen dessert manufacturing apparatus 38 manufactures frozen desserts such as popsicles on sticks. Multiple mold sets 14 are attached to a circulating chain 16 at equal intervals and circulate along a predetermined circulating path in the circulating direction Ca as the circulating chain 16 rotates. This circulating path consists of an upper path and a lower path that are parallel to each other, as well as U-turn paths at both ends. When the mold 10 is moving along the upper path, the opening side faces upward, and when it is moving along the lower path, the opening side faces downward.

[0036] The frozen dessert ingredient filler 40 is located at the starting end of the upper path of the mold 10 and supplies the frozen dessert ingredients to the mold 10. The frozen dessert extractor 42 is located near the ending end of the upper path of the mold 10 and extracts the frozen dessert from the mold 10. The device for inserting the ice pop stick into the mold 10 is not shown in the figure, but it is located slightly downstream of the frozen dessert ingredient filler 40 in the circumferential direction Ca of the circumferential chain 16. The frozen dessert is extracted from the frozen dessert extractor 42 by gripping the stick.

[0037] The manufacturing / detection switching device 44 controls the operation of the frozen dessert raw material filler 40 and the frozen dessert extractor 42. Specifically, when manufacturing frozen desserts using the mold 10, the manufacturing / detection switching device 44 switches the frozen dessert raw material filler 40 and the frozen dessert extractor 42 to the operating state, and during the pinhole detection period of the mold 10, it switches the frozen dessert raw material filler 40 and the frozen dessert extractor 42 to the non-operating state. In other words, during the pinhole detection period of the mold 10, the mold 10 passes through the storage tank 20 empty, without being supplied with frozen dessert raw materials from the frozen dessert raw material filler 40.

[0038] The storage tank 20 is located in the section of the upper path of the mold 10 that includes the area between the frozen dessert raw material filler 40 and the frozen dessert extractor 42, and stores brine 22 at a predetermined level. As the mold 10 passes through the storage tank 20, its opening is maintained above the level of the brine 22, that is, it is immersed in the brine 22 to a depth range that prevents the brine 22 from entering the mold 10 from the opening. Although not shown in the figures, bypasses (not shown) are formed at both ends of the storage tank 20 so that the mold 10 can be easily inserted into and removed from the storage tank 20 at both ends in the circumferential direction Ca while it is circulating on the circumferential chain 16.

[0039] Here, we define "circular cycle," "row number," and "circular row." A "circular cycle" refers to each mold 10 completing one revolution around the circular path. In addition, multiple molds 10 in each mold set 14 maintain the same position in the circular direction Ca as they circulate. In each mold set 14, numbers are assigned sequentially from one end to the other in the connecting direction of the connecting plate 12, and the same row number (e.g., row 1, row 2, ..., row n) is assigned to molds 10 with the same row number throughout the entire frozen dessert manufacturing apparatus 38a. A circular row of multiple molds 10 is formed for each row number. Therefore, there are as many circular rows as there are row numbers.

[0040] The UV lamp 26 and monochrome camera 28 are positioned downstream of the frozen dessert extractor 42 in the circumferential direction Ca along the circumferential path of the mold 10. In Figure 3, a pair of UV lamps 26 and monochrome camera 28 are used to irradiate all molds 10 on each connecting plate 12 with UV light and to photograph the inner surface. However, a pair of UV lamps 26 and monochrome camera 28 can also be provided for each mold 10 on each connecting plate 12, or for every predetermined number of molds 10 that are continuous in the longitudinal direction of the connecting plate 12.

[0041] The cleaning nozzle 46 is located at the starting end of the lower path of the mold 10. The cleaning nozzle 46 sprays cleaning water into the empty mold 10 after the frozen dessert has been removed by the frozen dessert extractor 42, thereby cleaning the inside of the mold 10.

[0042] In the first operational example of the frozen dessert manufacturing apparatus 38a, the manufacturing / detection switching device 44 causes all rows to rotate simultaneously in a manufacturing cycle during the first of two rotations, and causes all rows to rotate simultaneously in a detection cycle during the second rotation. During the manufacturing cycle, pinhole detection of the molds 10 by the UV lamps 26 and monochrome cameras 28 is stopped, and frozen desserts are manufactured for all molds 10. During the detection cycle, all molds 10 rotate empty, and pinhole detection of the molds 10 is performed by the UV lamps 26 and monochrome cameras 28.

[0043] In the second operational example of the frozen dessert manufacturing apparatus 38a, each mold 10 or each mold set 14 is assigned an ID (identifier), and the manufacturing / detection switching device 44 manages each mold 10 or mold set 14 individually based on the ID. Then, only the number sequence to which the mold 10 in which a pinhole was found belongs is designated as a mold 10 whose manufacturing has been stopped, preventing further filling of frozen dessert ingredients from the frozen dessert ingredient filler 40, while the other molds 10 are controlled to allow the manufacture of frozen desserts to continue.

[0044] In a second example of operation of the frozen dessert manufacturing apparatus 38a, the mold set 14 to which the mold 10 in which a pinhole was found belongs can be replaced with a new mold set 14 at an appropriate time, and the apparatus can be put back into use.

[0045] (Frozen dessert manufacturing equipment / 2nd application example) Figure 4 is an explanatory diagram of the switching between the manufacturing cycle and the detection cycle in a frozen dessert manufacturing apparatus 38b (second application example) equipped with a pinhole detection device. Figure 4 shows the right side view of the frozen dessert manufacturing apparatus 38b. In Figure 4, "〇" indicates the rotational sequence of the manufacturing cycle (frozen dessert manufacturing sequence), and "◇" indicates the rotational sequence of the detection cycle (pinhole detection sequence).

[0046] In the frozen dessert manufacturing apparatus 38b, the manufacturing / detection switching device 44 (Figure 2) can switch between the manufacturing cycle and the detection cycle for each circular row. In this example of switching by the frozen dessert manufacturing apparatus 38b, one circular row is selected from all the circular rows to be the circular row for the detection cycle, and all the remaining circular rows are selected to be the circular rows for the manufacturing cycle. Then, every (1+α) circular cycles, the circular rows for the detection cycle are shifted one by one from one end to the other in the longitudinal direction of the connecting plate 12 (meaning the transition from the upper row to the next row below in Figure 4). Note that 0 < α < 1.

[0047] The reason the switching cycle is set to (1+α) cycles is that it takes one cycle from the time the first mold 10 of each rotational row passes the frozen dessert raw material filler 40 in the rotational direction Ca until the last mold 10 of that rotational row passes the frozen dessert raw material filler 40, and it takes α cycles until the last mold 10 reaches the UV lamp 26 and monochrome camera 28 and the presence or absence of a pinhole is determined.

[0048] By setting α=1, the detection cycle sequence can also be shifted by one position from one end to the other in the longitudinal direction of the connecting plate 12 every two cycles.

[0049] In this way, production can be stopped in only some of the circular rows, while production continues in the others, allowing the entire frozen dessert manufacturing apparatus 38b to perform pinhole detection and frozen dessert production in parallel. Furthermore, it is possible to select multiple circular rows (e.g., two or three rows) for detection, rather than just one.

[0050] The advantage of the frozen dessert manufacturing apparatus 38a and 38b is that, compared to conventional frozen dessert manufacturing apparatuses that are dedicated to frozen dessert manufacturing without pinhole detection, there is no need to extend the chain-type circulating chain 16 for pinhole detection, and the conventional chain-type circulating chain 16 can be used as is.

[0051] (Frozen dessert manufacturing equipment / 3rd application example) Figure 5 is a front view of the main part of the frozen dessert manufacturing apparatus 38c (third application example) equipped with a pinhole detection device. In the frozen dessert manufacturing apparatus 38c, a pinhole detection section is added upstream of the frozen dessert manufacturing section in the circumferential direction Ca in the upper path of the circumferential path of the mold 10. Therefore, the length of the chain-type circumferential chain 16 of the frozen dessert manufacturing apparatus 38c is longer than the length of the frozen dessert manufacturing apparatuses 38a and 38b by the length of the detection section.

[0052] In Figure 5, only the end of the manufacturing section on the detection section side is shown, but the entire manufacturing section is the same as the configuration in Figure 2, excluding the right-hand U-turn path. However, since the monochrome camera 28 and UV cut filter 30 have been moved to the detection section, the monochrome camera 28 and UV cut filter 30 shown in Figure 2 are omitted from the third application example.

[0053] In the frozen dessert manufacturing apparatus 38c, the upper path is divided into an upstream detection section and a downstream manufacturing section. In the upstream detection section, each mold 10 is inspected for the presence or absence of pinholes. In the downstream manufacturing section, frozen dessert ingredients are supplied only to molds 10 that are determined to be pinhole-free, and the molds are cooled with brine solution 22 to produce frozen desserts. Therefore, the production of frozen desserts (supply of frozen dessert ingredients) can be immediately stopped for molds 10 that have pinholes, thus reducing waste in production. Furthermore, even if pinholes are found in some molds 10, production of frozen desserts can continue for molds 10 that do not have pinholes, or for other rows of molds 10 that do not have pinholes, thus avoiding an immediate complete shutdown of production.

[0054] In the manufacturing / detection switching device 44 of the frozen dessert manufacturing apparatus 38c, the function of switching between the manufacturing cycle and the detection cycle can be omitted. This is because both the manufacturing of frozen desserts and the detection of pinholes in the mold 10 are carried out continuously in each cycle, and switching is unnecessary.

[0055] Furthermore, the manufacturing / detection switching device 44 in Figure 5 may also be configured to switch between the manufacturing cycle and the detection cycle. In this case, the switching can be performed in three ways for each lap cycle: (a) both manufacturing and detection are performed, (b) only manufacturing is performed, and (c) only detection is performed. The manufacturing / detection switching device 44 can also switch between (a) to (c) for each lap train or for each predetermined lap cycle. For example, it is possible to operate primarily in (b) while switching to (c) so that it occurs once every few lap cycles, or to switch to (c) periodically (e.g., at the beginning or end of each day or week) and switch to (b) for the rest of the cycles.

[0056] (modified version) A chain-type circulating chain 16 is used as the circulating conveying device. The circulating conveying device may also be of the belt type.

[0057] The circumferential path of mold 10 is formed in a front view (e.g., Figures 2 and 5). However, the frozen dessert manufacturing method and apparatus of the present invention may also be of a type where the circumferential path is in a plan view (top view). [Explanation of Symbols]

[0058] 10...Mold (mold for frozen dessert production), 12...Connecting plate, 14...Mold set, 16...Circular chain (support part), 20...Storage tank (immersion part), 22...Brine solution, 26...UV lamp (excitation light irradiation part), 28...Monochrome camera (imaging part), 30...UV cut filter, 31...Traces, 32...Image analysis device (imaging analysis part and judgment part), 38a, 38b, 38c...Frozen dessert production equipment, 40...Frozen dessert raw material filler, 42...Frozen dessert extractor, 44...Production / detection switching device, 46...Washing nozzle, Ca...Circular direction.

Claims

1. A method for detecting pinholes in a mold for making frozen desserts, which has a containment section for containing a liquid and solidifies the liquid, A method for detecting pinholes in a mold for making frozen desserts, comprising immersing the mold in a brine solution to which a fluorescent food coloring has been added, and detecting the pinholes in the mold for making frozen desserts.

2. A method for detecting pinholes in a mold for making frozen desserts according to claim 1, wherein the pinhole detection is performed on the mold for making frozen desserts while it is moving in the brine solution.

3. The process involves immersing the mold for making frozen desserts, in which the housing portion is open through an opening, to a depth in which the opening is not submerged in the brine solution, An excitation light irradiation step is performed by irradiating the mold for making frozen desserts, which has been immersed in the immersion step, with excitation light through the opening to cause the food coloring on the inner surface of the housing to fluoresce; The imaging step involves receiving the reflected light from the inner surface after the excitation light has been reflected, and imaging the inner surface. A method for detecting pinholes in a mold for making frozen desserts according to claim 1, including the method described in claim 1.

4. An image analysis step is performed to detect the fluorescence emission of the food coloring from the image captured in the imaging step, A determination step is made based on the presence or absence of traces as detection points for the fluorescence emission in the captured image, to determine that the mold for making frozen desserts has pinholes if the traces are present, and to determine that the mold for making frozen desserts does not have pinholes if the traces are absent. A method for detecting pinholes in a mold for making frozen desserts according to claim 3, including the method described in claim 3.

5. The method for detecting pinholes in a mold for making frozen desserts according to claim 4, wherein the imaging in the imaging step is performed through a filter that selectively increases the transmittance of fluorescence emitted from the food coloring when irradiated with the excitation light.

6. The method for detecting pinholes in a mold for making frozen desserts according to claim 5, wherein the food coloring used is a food coloring having fluorescent emission properties, the excitation light is ultraviolet light, and the filter used is either a cut filter that cuts out ultraviolet light and the purple component of visible light below 420 nm, or a bandpass filter that selectively transmits the wavelength range component of the fluorescence of the food coloring in response to the excitation light.

7. The method for detecting pinholes in a mold for making frozen desserts according to claim 3, wherein each of the processes, the immersion step, the excitation light irradiation step, and the imaging step, is performed on the mold for making frozen desserts that is moving in a predetermined circular path.

8. The aforementioned circular path is a path in which a plurality of molds for making frozen desserts are spaced apart in the circular direction within the circular path. The pinhole detection method for frozen dessert molds according to claim 7, wherein the excitation light irradiation step and the imaging step are performed on each frozen dessert mold that has reached a predetermined position in the circular path.

9. Multiple predetermined positions are set along the circular path. The pinhole detection method for a mold for making frozen desserts according to claim 8, wherein the irradiation angle of the excitation light in the excitation light irradiation step and the imaging angle in the imaging step differ for each predetermined position.

10. The pinhole detection method for a mold for making frozen desserts according to claim 7, wherein the circulating path also serves as a path for manufacturing frozen desserts in the mold for making frozen desserts.

11. A pinhole detection device for detecting pinholes in a mold for making frozen desserts, which has a containment section for containing a liquid and solidifies the liquid, A pinhole detection device for frozen dessert molds, which detects the pinholes in the frozen dessert mold while the mold is immersed in a brine solution to which a fluorescent food coloring has been added.

12. A pinhole detection device for a frozen dessert mold according to claim 11, which performs pinhole detection on the frozen dessert mold while it is moving in the brine solution.

13. The mold for making frozen desserts, in which the housing portion is open through an opening, is immersed in a depth such that the opening is not submerged in the brine solution, An excitation light irradiation unit is provided to irradiate the mold for making frozen desserts, which is immersed in the immersion section, with excitation light through the opening to cause the food coloring on the inner surface of the containment section to fluoresce. An imaging unit that receives the reflected light from the inner surface after the excitation light has been reflected and images the inner surface, A pinhole detection device for a mold for making frozen desserts according to claim 11, including the above.

14. An image analysis unit detects the fluorescence emission of the food coloring from the image captured by the imaging unit, A determination unit determines, based on the presence or absence of traces as detection points for the fluorescence emission in the captured image, that if such traces are present, the mold for making frozen desserts has pinholes, and if such traces are absent, the mold for making frozen desserts does not have pinholes. A pinhole detection device for a mold for making frozen desserts according to claim 13, including the above.

15. The pinhole detection device for a mold for making frozen desserts according to claim 14, wherein the imaging unit performs imaging through a filter that selectively increases the transmittance of fluorescence emitted from the food coloring when irradiated with the excitation light.

16. The pinhole detection device for a mold for making frozen desserts according to claim 15, wherein the food coloring used is a food coloring having fluorescent emission properties, the excitation light is ultraviolet light, and the filter used is either a cut filter that cuts out ultraviolet light and the purple component of visible light below 420 nm, or a bandpass filter that selectively transmits the wavelength range component of the fluorescence of the food coloring in response to the excitation light.

17. The pinhole detection device for a frozen dessert mold according to claim 13, wherein the processing of the immersion unit, the excitation light irradiation unit, and the imaging unit is performed on the frozen dessert mold that is moving in a predetermined circular path, and the device is disposed at a predetermined position on the circular path through which the frozen dessert mold is moving in a circular path.

18. The aforementioned circular path is a path in which a plurality of the molds for making frozen desserts are spaced apart in the circular direction. The pinhole detection device for frozen dessert molds according to claim 17, wherein the excitation light irradiation unit and the imaging unit are used to process each frozen dessert mold that has moved to the predetermined position on the circular path.

19. Multiple predetermined positions are set along the circular path. The pinhole detection device for a mold for making frozen desserts according to claim 18, wherein the irradiation angle of the excitation light in the excitation light irradiation unit and the imaging angle in the imaging unit differ for each predetermined position.

20. The pinhole detection device for a mold for making frozen desserts according to claim 17, wherein the aforementioned circular path also serves as a path for manufacturing frozen desserts in the mold for making frozen desserts.

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