JP7845656B2 - Pallets and containers - Google Patents

Description

This invention relates to pallets and containers.

As a preservation method for maintaining the freshness of cooled items (objects to be preserved), such as food and living organisms, for extended periods, a method of creating an electric field (electrostatic field atmosphere) in the space inside the storage area in conjunction with refrigeration or freezing is known. In this method, by applying a high voltage inside the storage area, an electric field is created through voltage oscillation while the cooled items are refrigerated, making them less likely to freeze even near their freezing point. This enables long-term storage near the freezing point (see, for example, Patent Documents 1-3).

Utility Model Registration No. 3218537 Gazette Japanese Patent Publication No. 2011-182697 Japanese Patent Publication No. 2022-013221

The preservation method described above involves applying a high voltage to create an electric field, causing the water molecules in the cooled material to vibrate slightly, making them less likely to bond with each other, thereby preventing the cooled material from freezing. Therefore, in this preservation method, it is crucial to maintain a stable electric field within the storage area. Furthermore, if the cooled material is transported and moved between multiple refrigerated containers or freezer compartments, changing its storage location, an electric field generator must be installed in all refrigerated containers or freezer compartments where the cooled material may be stored, to ensure a stable electric field within the storage area.

The pallets and containers in this invention were devised in light of these challenges, with the aim of forming a stable electromagnetic field inside the storage area, maintaining the freshness of the cooled items (items to be stored) for a long period of time, and reducing the installation cost of electric field generators. Furthermore, this invention is not limited to these objectives; another objective is to achieve effects and benefits that cannot be obtained by conventional technology, as derived from the various configurations shown in the embodiments for carrying out the invention described later.

(1) The pallet disclosed herein is one of a plurality of pallets arranged in a room equipped with a refrigerator, and comprises a plurality of first conductor plates laid on one surface of the one pallet, and a generator for applying a voltage to the plurality of first conductor plates to form an electromagnetic field in a space formed by the plurality of first conductor plates, a second conductor plate forming a ceiling surface facing the first surface in the room, and an insulating plate forming a surface facing the interior of the room excluding the first surface and the ceiling surface , wherein the generator controls the application of voltage to the plurality of first conductor plates laid on the one pallet and the other pallets of the plurality of pallets .

(2) Preferably, the pallet further comprises a non-conductive plate laid on one surface so as to cover the plurality of first conductive plates.

(3) Preferably, the plurality of first conductor plates are laid on the surface of the first conductor plate with gaps between them, and the generating device controls the voltage applied to each of the first conductor plates.

(5) The container disclosed herein is a container equipped with a refrigerator and on which a plurality of pallets are arranged, comprising: a plurality of first conductor plates laid on one surface of each of the plurality of pallets; a second conductor plate forming a ceiling surface opposite to the first surface; an insulating plate forming a surface facing the interior of the container, excluding the first surface and the ceiling surface; and a generator for applying a voltage to the plurality of first conductor plates to form an electromagnetic field in the internal space of the container , wherein the generator controls the application of voltage to the plurality of first conductor plates laid on one pallet and the other pallets of the plurality of pallets, respectively .

According to the disclosed container, a stable electromagnetic field can be formed inside the container, thereby maintaining the freshness of the cooled items (stored items) for a long period of time and reducing the installation cost of the electric field generator.

This is a perspective view showing a container according to an embodiment. Figure 1 shows the container with its opening door open, as viewed from outside the container. This is a diagram (corresponding to Figure 2) that explains the function of the container in Figure 1. This is a plan cross-sectional view illustrating the arrangement of pallets 21 inside the container shown in Figure 1. Figure 1 shows the measurement results of the electric field distribution inside the container. Figure 1 shows the measurement results of the electric field distribution inside the container. Figure 1 shows the measurement results of the electric field distribution inside the container. Figure 1 shows the measurement results of the electric field distribution inside the container. Figure 1 shows the measurement results of the electric field distribution inside the container. Figure 1 shows the measurement results of the electric field distribution inside the container. Figure 1 shows the measurement results of the electric field distribution inside the container. Figure 1 shows the measurement results of the electric field distribution inside the container. Figure 1 shows the measurement results of the electric field distribution inside the container. These figures illustrate the measurement locations for the electric field distribution shown in Figures 5A to 5I. This is a unit conversion table for electric fields.

The pallet 21 and container 1 as embodiments will be described with reference to the drawings. The embodiments shown below are merely illustrative, and there is no intention to exclude various modifications or applications of techniques not explicitly stated in the embodiments below. The configuration of these embodiments can be modified in various ways without departing from their spirit. Furthermore, they can be selected or combined as needed.

[1. Structure]
Figure 1 is a perspective view showing container 1 of this embodiment. Container 1 is a storage container for refrigerating and preserving items to be cooled, such as food or living organisms (hereinafter referred to as "items to be preserved"), and is used, for example, in cargo transport. Container 1 is equipped with a well-known refrigerator 8. Container 1 of this embodiment has a rectangular parallelepiped shape, with the refrigerator 8 located at one end in the longitudinal direction (upper left in Figure 1) and an opening/closing door 5 located at the other end in the longitudinal direction (lower right in Figure 1). In other words, container 1 of this embodiment has an opening only at the other end, and this opening is closed by the opening/closing door 5.

The refrigeration unit 8 is positioned in a storage compartment 9 located at one end of the container 1. The storage compartment 9 is a recessed portion formed from the end face of one end of the container 1 into the internal space of the container 1.

Multiple pallets 21 are arranged on the bottom surface 2 of container 1. In the example shown in Figure 1, twelve pallets 21 (six in the longitudinal direction and two in the width direction) are arranged on the bottom surface 2 of container 1. The longitudinal and width directions of the pallets 21 in Figure 1 may be, for example, 1000 mm x 1000 mm (or 1100 mm x 1100 mm). That is, in Figure 1, since six pallets 21 in the longitudinal direction and two in the width direction are arranged across one side of the bottom surface 2 of container 1, the dimensions of the bottom surface 2 of container 1 are 6000 mm (or 6600 mm) in the longitudinal direction and 2000 mm (or 2200 mm) in the width direction.

A portion of the electromagnetic field generator 10 and the step-down transformer 14 are arranged in the internal space formed between the top and bottom surfaces of the pallet 21.

The generator 10 includes a control box 11 containing a transformer and control means for generating high voltage, a relay device 12 for controlling the voltage application to the first conductor plate 211 (described later), and a high-voltage cable 13. The high-voltage cable 13 is provided at the points connecting the control box 11 and the relay device 12, the relay device 12 and the first conductor plate 211, and the pallet 21 and other pallets 21, respectively.

The step-down transformer 14 reduces the voltage from the refrigerator 8 or external power supply and supplies power to the control box 11 of the generator 10. The terminals on the terminal block of the step-down transformer 14 are connected to the terminals at the end of the power cable of the refrigerator 8 and the terminals at the end of the power cable of the control box 11. Note that the connection method of these devices (step-down transformer 14, control box 11, relay device 12, etc.) is just one example.

The generator 10 and the step-down transformer 14 only need to be installed on at least one of the multiple pallets 21 arranged inside the container 1. The pallet 21 equipped with the generator 10 and the step-down transformer 14 (in other words, the main pallet 21) is connected to the other pallets 21 by high-voltage cables 13, thereby applying voltage to the first conductor plates 211 of the other pallets 21. Note that the main pallet 21 and each of the other pallets 21 do not necessarily need to be directly connected by the high-voltage cables 13. For example, the main pallet 21 may be connected to a first other pallet 21, the first other pallet 21 to a second other pallet 21, the second other pallet 21 to a third other pallet 21, and so on, with each pallet 21 connected in a daisy-chain fashion by the high-voltage cables 13.

Multiple (three in the example shown in Figure 1) first conductor plates 211 are laid on the surface of each pallet 21. In the example shown in Figure 1, three first conductor plates 211 are laid parallel to the width direction of the container 1, but the first conductor plates 211 may also be laid parallel to the longitudinal direction of the container 1. Furthermore, a non-conductive plate 212 is laid on top of the multiple first conductor plates 211, covering them completely. The non-conductive plate 212 can be a thin sheet made of a material such as resin (FRP, ABS) or foamed polyethylene.

Next, the internal structure of container 1 will be described. Figure 2 is a view from outside the container of container 1 with the opening/closing door 5 of container 1 in the open position. As shown in Figure 2, container 1 comprises multiple pallets 21 forming a first conductive plate 211 laid on the internal bottom surface 2, a second conductive plate 22 forming a ceiling surface 6 opposite the bottom surface 2, and insulating plates 23 that form the surfaces facing the inside of container 1, excluding the bottom surface 2 and the ceiling surface 6. In other words, only the upper and lower surfaces (the surfaces with the shaded pattern in Figure 2) of container 1 conduct electricity, while the other surfaces (the surfaces with the dotted pattern in Figure 2) do not conduct electricity. As a result, when a voltage is applied to one conductive plate (first conductive plate 211), the electricity flows to the other conductive plate (second conductive plate 22), which conducts electricity more easily, thus forming a stable electromagnetic field.

The first conductor plate 211 and the second conductor plate 22 can be made of thin metal sheets such as aluminum or stainless steel. If the ceiling surface 6 of the container 1 is originally made of a conductor, that ceiling surface 6 can be used as the second conductor plate 22. On the other hand, even if the bottom surface 2 of the container 1 is originally made of a conductor, as shown in Figures 1 and 2, multiple first conductor plates 211 are arranged side-by-side using multiple pallets 21 to cover the entire bottom surface 2. The items to be stored are placed on top of the first conductor plates 211.

The insulating plate 23 can be a thin sheet made of a material such as resin (FRP, ABS) or foamed polyethylene. The insulating plate 23 is attached to both sides 7 in the width direction of the container 1, the inner surface facing the inside of the opening/closing door 5, and the side 7 at one end in the longitudinal direction. The method of attachment is not particularly limited; it can be attached using industrial adhesive or double-sided tape. It is preferable to seal the gaps after attaching the insulating plate 23.

Figure 3 is a diagram illustrating the operation of container 1 in Figure 1 (corresponding to Figure 2). According to the container 1 described above, an electromagnetic field can be generated by applying a voltage to the first conductor plate 211 laid on the bottom surface 2. Since the inner surfaces other than the bottom surface 2 and the top surface 6 are made of insulating plates 23, the direction of electric current flow can be determined from bottom to top, as shown in Figure 3. In other words, in the container 1 described above, the voltage (electricity) applied to the first conductor plate 211 flows towards the top surface 6, which is easier to access, thus forming a stable electromagnetic field.

Figure 4 is a plan cross-sectional view illustrating the arrangement of pallets 21 within container 1 in Figure 1. In the example shown in Figure 4, pallets #1-1 to #1-6 and #2-1 to #2-6 are arranged as pallets 21 within container 1. Pallets #1-1 to #1-6 belong to electrode group #1, and pallets #2-1 to #2-6 belong to electrode group #2. Electrode group #2 is located on the entrance/exit side of container 1 (the side of the opening/closing door 5 in Figure 1), while electrode group #1 is located on the side opposite the opening/closing door 5 (the side of the refrigerator 8 in Figure 1).

One of the pallets #1-1 to #1-6 belonging to electrode group #1 may function as the main pallet 21, and one of the pallets #2-1 to #2-6 belonging to electrode group #2 may also function as the main pallet 21. The main pallet 21 of each electrode group applies voltage to the first conductor plate 211 of the main pallet 21 and to the first conductor plates 211 of other pallets 21 belonging to the same electrode group. The main pallet 21 may apply voltage to one or more pallets 21 sequentially in a relay manner. Note that electrode groups are not defined, and one main pallet 21 may apply voltage to the first conductor plates 211 of all pallets 21 in container 1. Furthermore, three or more electrode groups may be defined within container 1.

In Figure 4, the direction from left to right when viewing container 1 from the entrance side to the back is defined as the x-axis, the direction from the entrance side to the back is defined as the y-axis, and the vertically upward direction is defined as the z-axis. Furthermore, point A1 is defined between containers #1-1 and #1-2, point A2 is defined in the center of container #1-3, point A3 is defined between containers #1-3 and #1-4, point A4 is defined in the center of container #1-4, and point A5 is defined between containers #1-5 and #1-6.

A voltage of 3.5 kV was applied to pallets #1-1 to #1-6. When the electric field strength was measured at a height near the first conductor plate 211 at points A1 to A5, the values were 15.841 kV/m, 11.455 kV/m, 10.295 kV/m, 11.893 kV/m, and 15.024 kV/m, respectively. When the electric field strength was measured at a height approximately midway between the first conductor plate 211 and the second conductor plate 22 at points A1 to A5, the values were 0.678 kV/m, 0.8396 kV/m, 0.9667 kV/m, 0.9432 kV/m, and 0.7986 kV/m, respectively. At points A1 to A5, the electric field strength was measured at the height near the second conductor plate 22, yielding values of 0.1663 kV/m, 0.321 kV/m, 0.4 kV/m, 0.3142 kV/m, and 0.2093 kV/m, respectively. The electric field strength decreased at the height near the second conductor plate 22, and the electric field strengths were generally symmetrical in the x-axis and y-axis directions.

Next, when the electric field sensor was placed on a vertically stacked cardboard sheet (approximately midway between the first conductor plate 211 and the second conductor plate 22) and the electric field strength was measured, the reading at point A3 was 5.1342 kV/m. In other words, the electric field strength on a dielectric material such as cardboard was higher compared to the electric field strength of 0.9667 kV/m at the same location when no cardboard was placed.

Figures 5A to 5I show the measurement results of the electric field distribution inside container 1 in Figure 1. Figure 6 is a diagram illustrating the measurement locations of the electric field distribution shown in Figures 5A to 5I. Figure 7 is a unit conversion table for electric fields. As shown in Figure 6, nine electric field sensors 100 (electric field sensors #1 to #9) are placed on any surface parallel to the surface of the first conductor plate 211. Converting the units of electric field [dBkV/m] shown in Figures 5A to 5I to electric field [kV/m] results in the unit conversion table shown in Figure 7.

Figure 5A shows the electric field distribution measured by electric field sensors #1 to #9 on planes at Z=0, +20, and +40. Figure 5B shows the electric field distribution based on the electric field strength measured by electric field sensors #2, #4, #6, and #8 on any plane from Z=0 to +50. Figure 5C shows the electric field distribution at a cross-section of Y=-15 based on the electric field strength measured by electric field sensors #4 to #9 on any plane from Z=0 to +50. Figure 5D shows the electric field distribution at a cross-section of Y=-10 based on the electric field strength measured by electric field sensors #4 to #9 on any plane from Z=0 to +50. Figure 5D also shows the electric field distribution at a cross-section of Y=-5 based on the electric field strength measured by electric field sensors #4 to #9 on any plane from Z=0 to +50. Figure 5F shows the electric field distribution at a cross-section of Y=-0, based on the electric field strength measured by electric field sensors #4 to #6, for any plane between Z=0 and +50. Figure 5G shows the electric field distribution at a cross-section of Y=5, based on the electric field strength measured by electric field sensors #1 to #6, for any plane between Z=0 and +50. Figure 5H shows the electric field distribution at a cross-section of Y=10, based on the electric field strength measured by electric field sensors #1 to #6, for any plane between Z=0 and +50. Figure 5I shows the electric field distribution at a cross-section of Y=15, based on the electric field strength measured by electric field sensors #1 to #6, for any plane between Z=0 and +50.

As shown in Figures 5A to 5I, the electric field strength is high near Z=0 and low near Z=50.

[2. Effects]

(1) The pallet 21 comprises a plurality of first conductor plates 211 laid on one surface of the pallet 21, and a generator 10 for forming an electromagnetic field in the space formed by the first conductor plates 211, a second conductor plate 22 that forms the ceiling surface 6 facing one surface inside the room, and an insulating plate 23 that forms the surface facing the interior of the room, excluding the bottom surface 2 and the ceiling surface 6. This allows for the formation of a stable electromagnetic field inside the storage area (the internal space of the container 1), thereby maintaining the freshness of the cooled items (items to be stored) for a long period and reducing the installation cost of the generator 10. Specifically, even when the cooled items are transported and moved between multiple refrigerated containers or freezers, changing their storage location, the generator 10 only needs to be installed on the pallet 21 on which the cooled items are placed; therefore, it is not necessary to prepare a generator 10 for each storage location of the cooled items.

(2) The pallet 21 further comprises a non-conducting plate 212 laid so as to cover a plurality of first conductor plates 211 on one surface. This prevents leakage of current from the first conductor plates 211 to the object being cooled.

(3) Multiple first conductor plates 211 are laid on a surface with gaps between them, and the generator 10 controls the voltage applied to each first conductor plate 211. This reduces the resistance of the capacitor formed by the first conductor plates 211 and the second conductor plate 22, thereby reducing the power consumption of the generator 10.

(4) In the room, other pallets 21 each having at least multiple first conductor plates 211 are arranged, and the generator 10 controls the voltage application to the multiple first conductor plates 211 laid on each pallet 21 and the other pallets 21. This allows only one generator 10 to be provided for multiple pallets 21, and the power consumption is also reduced to that of a single generator 10, thus significantly reducing power consumption.

[3. Others]
The configuration of container 1 described above is merely an example and is not limited to that. For example, the side portion of container 1 may be curved, or it may have openings and doors on its side portion. Alternatively, container 1 may be a refrigerated room capable of storing pallets 21.

In the embodiment described above, the generator 10 and the step-down transformer 14 are arranged on the pallet 21, but the arrangement of these devices is not limited to this. The generator 10 and the step-down transformer 14 may also be arranged on the container 1.

1: Container 2: Bottom 5: Opening/closing door 6: Top 7: Side 8: Refrigerator 9: Storage section 10: Generator 11: Control box 12: Relay device 13: High-voltage cable 14: Step-down transformer 21: Pallet 22: Second conductor plate 23: Insulating plate 100: Field sensor 211: First conductor plate 212: Non-conductor plate

Claims (7)

One of several pallets placed in a room equipped with a refrigerator,
A plurality of first conductive plates laid on one surface of the aforementioned pallet,
A generator for generating an electromagnetic field in a space formed by the plurality of first conductor plates, the plurality of first conductor plates, a second conductor plate forming a ceiling surface facing the first surface in the room, and insulating plates forming surfaces facing the interior of the room, excluding the first surface and the ceiling surface, by applying a voltage to the plurality of first conductor plates,
Equipped with ,
The generating device controls the application of voltage to the plurality of first conductor plates laid on one pallet and the other pallets, respectively, among the plurality of pallets , and is characterized by this pallet. The pallet according to claim 1, further comprising a non-conductive plate laid so as to cover the plurality of first conductive plates on the surface of the first plate. The plurality of first conductor plates are laid on the surface of the first conductor plate with gaps between them,
The generating device controls the application of voltage to each of the plurality of first conductor plates.
A pallet according to claim 1 or 2, characterized in that it is the same as the one described in claim 1 or 2 . A container equipped with a refrigeration unit and on which multiple pallets are placed,
A plurality of first conductive plates laid on one surface of each of the plurality of pallets,
A second conductive plate forming a ceiling surface opposite to the first surface,
An insulating plate that forms a surface facing the inside of the container, excluding the first surface and the ceiling surface,
A generator for applying a voltage to the plurality of first conductor plates to form an electromagnetic field in the internal space of the container,
Equipped with ,
A container characterized in that the generating device controls the application of voltage to the plurality of first conductor plates laid on one of the plurality of pallets and on the other pallets, respectively . The container according to claim 4 , further comprising a non-conductive plate laid on one surface so as to cover the plurality of first conductive plates. The plurality of first conductor plates are laid on the surface of the first conductor plate with gaps between them,
The generating device controls the application of voltage to each of the plurality of first conductor plates.
The container according to claim 4 or 5, characterized in that it is a container according to claim 4 or 5 . The generating device is provided on the pallet,
A container according to any one of claims 4 to 6, characterized in that it is a container according to any one of claims 4 to 6 .