Hydroponic tray

Abstract

To provide a hydroponic tray which enables horizontal conveyance using a free conveyor.SOLUTION: The present invention provides a hydroponic tray, the tray comprising a bottom and side portions that extend upward to surround the bottom. The tray comprises an inner wall disposed inside the tray and an outer wall disposed outside the inner wall. The side portion is provided with an engagement recess formed by upwardly recessing the outer wall. The engagement recess comprises an inner side wall and an outer side wall, the inner side wall and the outer side wall being a pair of side walls of the engagement recess. The inner side wall is disposed further inward of the tray than the outer side wall.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a tray for hydroponic cultivation. [Background technology]

[0002] Patent Document 1 discloses a cultivation device for hydroponically cultivating plants. In this cultivation device, a cultivation tank for holding a culture solution for growing plants is placed on a cultivation unit and transported by a conveyor device. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2022-23725 Summary of the Invention [Problem to be solved by the invention]

[0004] In Patent Document 1, the cultivation units are transported by a conveyor device that has a built-in drive unit such as a motor, but such conveyor devices have the problem that they are expensive to install and maintain, so it is desirable to transport the cultivation units horizontally using a free conveyor that does not have a built-in drive unit.

[0005] The present invention has been made in view of the above circumstances, and provides a tray for hydroponic cultivation that can be transported in a horizontal direction using a free conveyor. [Means for solving the problem]

[0006] According to the present invention, the following inventions are provided. [1] A tray for hydroponic cultivation, comprising: a bottom; and side portions rising to surround the bottom; an inner wall disposed on the inside of the tray; and an outer wall disposed outside the inner wall; the side portions are provided with an engagement recess formed by recessing the outer wall upward; the engagement recess comprises an inner wall and an outer wall, the inner wall and the outer wall being a pair of side walls of the engagement recess; and the inner wall is disposed inside the tray relative to the outer wall. [2] The tray according to [1], wherein a first welding portion at which the inner wall and the outer wall are welded to each other is provided on the inner wall. [3] A tray as described in [1] or [2], wherein the direction in which the inner wall and the outer wall face each other is defined as a first direction, and the engagement recess extends in a second direction perpendicular to the first direction. [4] A tray according to any one of [1] to [3], wherein a reinforcing recess is provided adjacent to the engagement recess so as to extend in a first direction, where the direction in which the inner wall and the outer wall face each other is defined as a first direction. [5] A tray as described in [4], wherein a second welding portion at which the inner wall and the outer wall are welded to each other is provided at the bottom of the reinforcing recess. [6] The tray according to [4] or [5], wherein a pair of the reinforcing recesses are provided at positions adjacent to the engagement recesses. [7] A method for transporting a tray described in any one of [1] to [6], comprising the steps of: transporting the tray by moving a hook attached to a drive device in the direction of the inner wall or the outer wall while engaging the tip of the hook with the engagement recess. Effect of the Invention

[0007] In the hydroponic tray of the present invention, a first welding portion is provided on the inner wall of the engagement recess where the hook attached to the drive unit engages, whereby the inner wall and the outer wall are welded together. With this configuration, the hook of the drive unit can be engaged with the engagement recess to push and pull the tray. Therefore, for example, a large number of trays can be arranged in series on a free conveyor, and all the trays arranged in series can be moved simultaneously by pushing the tray at one end in the horizontal direction. In addition, the tray on the free conveyor can be removed from the conveyor by pulling the tray at the other end in the horizontal direction. Therefore, according to the present invention, a hydroponic tray is provided that can be transported horizontally using a free conveyor. [Brief description of the drawings]

[0008] [Figure 1] 1A and 1B are perspective views of a hydroponic tray 10 and a hook 4 according to one embodiment of the present invention, as viewed obliquely from above and below, respectively. [Diagram 2] Fig. 2A is an enlarged view of region A in Fig. 1B, and Fig. 2B is a perspective view of the state after the hook 4 has been engaged with the engagement recess 2f from the state in Fig. 2A. The dashed line in the figure indicates the change in curvature. The same applies to the other figures. [Diagram 3] 2 is a bottom view of the tray 10 and the hook 4 of FIG. 1. [Figure 4] FIG. 4 is an enlarged view of an area A in FIG. [Diagram 5] 5A to 5C are cross-sectional views taken along lines AA, BB, and CC in FIG. 4, respectively. [Figure 6] This shows a state after the hook 4 has been engaged with the engaging recess 2f from the state shown in FIG. 5A. [Figure 7] 7A and 7B are a cross-sectional view taken along line DD and EE in FIG. 4, respectively. [Figure 8] 8A and 8B are a plan view and a front view, respectively, of the transport device 5 that transports the tray 10. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, the embodiments of the present invention will be described. The various features shown in the following embodiments can be combined with each other. In addition, each feature can be an independent invention. Furthermore, in the following embodiments, elements that are not specified in the claims are optional elements and can be omitted.

[0010] 1.10 Hydroponic Trays A hydroponic tray 10 according to one embodiment of the present invention shown in Fig. 1 is used for hydroponic cultivation by storing a nutrient solution therein. The tray 10 is made of a hollow resin molded body.

[0011] The tray 10 is generally rectangular in plan view, with the dimension of its short side being, for example, 60 to 240 cm, preferably 80 to 160 cm, and more preferably 100 to 140 cm (120 cm in this embodiment). The dimension of its long side is, for example, specifically, 90 to 360 cm, preferably 120 to 270 cm, and more preferably 140 to 240 cm (180 cm in this embodiment). The thickness of the tray 10 is, for example, 5 to 20 cm, and preferably 8 to 14 cm (11.3 cm in this embodiment).

[0012] The tray 10 is in the shape of a container that is open at the top, and has a bottom 1 and side parts 2 that rise up to surround the bottom 1. In the following description, terms related to directions such as "upper", "lower", and "horizontal" refer to directions when the bottom 1 is placed on the ground.

[0013] The side portion 2 has a pair of long side portions 2k corresponding to the long sides of the rectangular side portion 2, and a pair of short side portions 2l corresponding to the short sides, and the long side portions 2k and the short side portions 2l are connected to each other at the corners. As shown in Figs. 5 to 7, the tray 10 has a double-wall structure including an inner wall 10a and an outer wall 10b. The inner wall 10a and the outer wall 10b are connected to each other by an upper wall 10c. The upper wall 10c is preferably horizontal. The inner wall 10a is disposed on the inner side of the tray 10, and the outer wall 10b is disposed on the outer side of the tray 10 with respect to the inner wall 10a. The distance between the inner surface of the inner wall 10a and the outer surface of the outer wall 10b is, for example, 10 to 50 mm, and preferably 20 to 40 mm (32 mm in this embodiment).

[0014] As shown in Figures 1B, 2A and 5A, the bottom 1 is provided with recesses 1a formed by recessing the outer wall 10b toward the inner wall 10a. The recesses 1a are cone-shaped. A large number of recesses 1a are provided approximately uniformly across the entire bottom 1. At the bottom of the recesses 1a, welded portions 1b are provided where the inner wall 10a and the outer wall 10b are welded to each other (also expressed as "joined" or "integrated"; the same applies below). The rigidity of the bottom 1 is increased by providing the recesses 1a and the welded portions 1b.

[0015] As shown in FIG. 5A, in the side portion 2, the inner wall 10a includes a lower inner wall 2a, a middle inner wall 2b, and an upper inner wall 2c in order from the inner wall 10a (hereinafter, bottom inner wall 1c) side in the bottom portion 1. The middle inner wall 2b has a gentler slope than the lower inner wall 2a and the upper inner wall 2c, and is preferably parallel to the bottom inner wall 1c. The middle inner wall 2b is preferably provided over the entire circumference of the tray 10. For example, a panel for holding a plant to be hydroponically grown can be placed on the middle inner wall 2b. The lower inner wall 2a has a steeper slope than the upper inner wall 2c. This is because the upper inner wall 2c has a relatively gentle slope to make it easier to insert a panel into the tray 10, while the lower inner wall 2a has a relatively steep slope to increase the amount of nutrient solution that can be accommodated in the tray 10.

[0016] As shown in FIG. 1A, the bottom 1 is provided with a first protrusion 1d and a second protrusion 1e that protrude upward. The first protrusion 1d is provided at the center of the bottom 1. The first protrusion 1d is disposed between a pair of second protrusions 1e. The first protrusion 1d and the second protrusion 1e are aligned along a second direction D2 to be described later. The first protrusion 1d and the second protrusion 1e are disposed at the center of the bottom 1 in the first direction D1 to be described later. The first protrusion 1d and the second protrusion 1e function as pillars that support a panel placed on the intermediate inner wall 2b. Therefore, the upper surfaces of the first protrusion 1d and the second protrusion 1e are substantially flush with the upper surface of the intermediate inner wall 2b. In addition, when multiple panels (for example, four panels) are arranged side by side in the tray 10, the upper surface of the first protrusion 1d is wider than the upper surface of the second protrusion 1e so that the corners of the panels can be supported by the first protrusion 1d.

[0017] The side portion 2 is provided with recesses 2d formed by recessing the outer wall 10b toward the inner wall 10a. The recesses 2d are provided on each of the long side portion 2k and the short side portion 2l. Examples of the recesses 2d include first to fourth recesses 2d1 to 2d4. It is preferable that each recess 2d is provided with at least one welded portion. Examples of the welded portions include first to fifth welded portions 2e1 to 2e5 described below.

[0018] As shown in Figs. 3 and 4, the long side portion 2k is provided with a first recess 2d1 and a second recess 2d2. The first recess 2d1 includes an engagement recess 2f and a reinforcing recess 2g. As shown in Figs. 5A and 5B, the engagement recess 2f is formed by recessing the outer wall 10b upward. The engagement recess 2f includes an inner wall 2f1 and an outer wall 2f2. The inner wall 2f1 and the outer wall 2f2 are a pair of side walls of the engagement recess 2f, and the inner wall 2f1 is disposed on the inner side of the tray 10 relative to the outer wall 2f2. The inner wall 2f1 is preferably provided with a first welded portion 2e1 in which the inner wall 10a and the outer wall 10b are welded to each other. The first welded portion 2e1 is preferably formed by welding the outer wall 10b to a portion 2h that spans the upper inner wall 2c and the middle inner wall 2b.

[0019] The engagement recess 2f is a portion that engages the tip 4c of the hook 4 attached to the drive unit 3 (shown in FIG. 8). The hook 4 includes a base 4a, an attachment portion 4b, and a tip 4c. The attachment portion 4b and the tip 4c are disposed so as to extend upward from the base 4a. The drive unit 3 is a device for moving the hook 4, and is, for example, a drive unit. The drive unit 3 is attached to the attachment portion 4b. A gap 4d is provided between the attachment portion 4b and the tip 4c, and when the tip 4c is engaged with the engagement recess 2f as shown in FIG. 2B and FIG. 6, the outer portion 2p provided outside the engagement recess 2f is accommodated in the gap 4d. With the tip 4c of the hook 4 engaged with the engagement recess 2f, the hook 4 is moved in the direction of the inner wall 2f1 or the outer wall 2f2 (i.e., in the horizontal direction), whereby the tray 10 can be transported (i.e., moved in the horizontal direction).

[0020] When the tray 10 is moved by pulling, usually only one tray is pulled, but when the tray 10 is pushed to move, multiple trays 10 may be arranged in series and all the trays may be moved simultaneously by pushing the endmost tray 10. For this reason, when the tray 10 is pushed, a large force is applied to the tray 10, which makes the tray 10 prone to deformation. On the other hand, in the tray 10 of this embodiment, the first welded portion 2e1 is provided on the inner wall 2f1 to which a large load from the hook 4 is likely to be applied, and the rigidity of the inner wall 2f1 is increased, so that deformation of the tray 10 when the tray 10 is pushed can be suppressed.

[0021] If the direction in which the inner wall 2f1 and the outer wall 2f2 face each other is the first direction D1, the engagement recess 2f preferably extends in the second direction D2 perpendicular to the first direction D1. That is, the engagement recess 2f preferably has an elongated shape extending in the second direction D2. The tip 4c of the hook 4 also has an elongated shape extending in the second direction D2. The tip 4c has a shape and size that can be accommodated in the engagement recess 2f with almost no gap, and the hook 4 and the engagement recess 2f are engaged by the tip 4c being accommodated in the engagement recess 2f. With this configuration, the force applied from the tip 4c to the tray 10 is easily dispersed, so that local deformation of the tray 10 is suppressed. The first direction D1 is, for example, the short side direction, and the second direction D2 is, for example, the long side direction. When the hook 4 pushes the tray 10, the hook 4 abuts against the inner wall 2f1.

[0022] The reinforcing recess 2g is provided at a position adjacent to the engaging recess 2f so as to extend in the first direction D1. That is, the reinforcing recess 2g has an elongated shape extending in the first direction D1. By providing the reinforcing recess 2g, it is possible to further suppress deformation of the tray 10 when the tray 10 is pushed. It is preferable to provide a pair of reinforcing recesses 2g at a position adjacent to each engaging recess 2f. In this case, it is possible to further suppress deformation of the tray 10 when the tray 10 is pushed. It is preferable to provide the reinforcing recess 2g so as to be continuous with the engaging recess 2f. As shown in FIG. 4 and FIG. 5B, the inner wall 2f1 at a portion 2q where the reinforcing recess 2g is not provided (i.e., a portion 2q1 between a pair of reinforcing recesses 2g or a portion 2q2 on the opposite side of the portion 2q1 with the reinforcing recess 2g in between) is higher than the inner wall 2f1 at the reinforcing recess 2g. Therefore, the contact area with the hook 4 is large at the portion 2q, making it easier to receive a load from the hook 4. On the other hand, it is preferable that the upper end of the reinforcing recess 2g does not reach the upper surface of the engagement recess 2f. In this case, as shown in Figures 5A and 6, the inner wall 2f1 of the engagement recess 2f is also present in the reinforcing recess 2g, and the load from the hook 4 can be received, and the load from the hook 4 can be effectively distributed over the entire inner wall 2f1 of the engagement recess 2f.

[0023] In addition, a second welded portion 2e2 is preferably provided at the bottom of the reinforcing recess 2g, where the inner wall 10a and the outer wall 10b are welded to each other. The second welded portion 2e2 is preferably configured by welding the outer wall 10b to a portion 2i that spans the bottom inner wall 1c and the lower inner wall 2a. In this case, deformation of the tray 10 when the tray 10 is pressed can be further suppressed. It is preferable to provide a hollow portion 2o, where the inner wall 10a and the outer wall 10b are not welded, between the first welded portion 2e1 and the second welded portion 2e2.

[0024] It is preferable that the portion 2j between the pair of reinforcing recesses 2g is a convex portion when viewed from the bottom of the reinforcing recess 2g. In this case, the side wall 2j1 (shown in FIG. 2A) of the portion 2j further increases the rigidity of the portion to which a strong force is applied when the tray 10 is pressed, and it is possible to further suppress deformation of the tray 10 when the tray 10 is pressed. As shown in FIG. 5B, it is preferable that the second welded portion 2e2 is not provided in the portion 2j.

[0025] In the second recess 2d2, first and second welded portions 2e1 and 2e2 are provided as shown in Fig. 5C. By providing such a recess, the rigidity of the tray 10 is further increased.

[0026] 3, two of the first and second recesses 2d1 and 2d2 are provided on each long side 2k. It is preferable that two of the second recesses 2d2 are provided between two of the first recesses 2d1.

[0027] As shown in Figs. 3 and 4, the short side portion 2l is provided with a third recess 2d3 and a fourth recess 2d4. As shown in Fig. 7A, the third recess 2d3 is provided with a third welded portion 2e3. The third welded portion 2e3 is formed by welding a corner 2m of the middle inner wall 2b and the upper inner wall 2c to the outer wall 10b. In the third recess 2d3, no portion other than the third welded portion 2e3 is welded. As shown in Fig. 7B, the fourth recess 2d4 is provided with a fourth welded portion 2e4 and a fifth welded portion 2e5. The fourth welded portion 2e4 is formed by welding the outer wall 10b to the middle inner wall 2b. The fifth welded portion 2e5 is formed by welding a corner 2n of the lower inner wall 2a and the bottom inner wall 1c to the outer wall 10b. As shown in Fig. 3, two third recesses 2d3 are provided on each short side 2l, and four fourth recesses 2d4 are provided on each short side 2l. Each third recess 2d3 is disposed between two fourth recesses 2d4 from the end. This configuration increases the rigidity of the short side 2l.

[0028] The recesses provided on the long side portion 2k and / or the short side portion 2l are preferably arranged symmetrically about the central plane in the first direction D1 and / or the second direction D2.

[0029] 2. Apparatus 5 and method for transporting trays 10 for hydroponic cultivation Next, the conveying device 5 and the method for conveying the trays 10 for hydroponic cultivation will be described with reference to FIG. 8. The conveying device 5 of this embodiment includes a pair of bases 6 and a free conveyor 7 arranged between them. The free conveyor 7 can be, for example, a roller conveyor without a power source. The plant factory has a work area where various tasks required for hydroponic cultivation are performed on the trays 10, and a cultivation shelf on which the trays 10 are placed and the plants are grown. Tasks performed in the work area include planting, harvesting, cleaning, and inspection. The trays 10 that have been worked on in the work area are conveyed to the base 6 by a conveying means (not shown), and are conveyed between the base 6 and the free conveyor 7 by the conveying device 5. The free conveyor 7 serves as a cultivation shelf. The free conveyor 7 has the advantage that the introduction cost and maintenance cost are lower than those of a conveyor with a power source. On the other hand, a large number of trays 10 are arranged in series on the free conveyor 7, and each tray 10 weighs, for example, 80 kg when filled with nutrient solution, so a means for efficiently conveying these trays 10 is important. The number of trays 10 that can be arranged in series is, for example, 10 to 60, and preferably 20 to 40 (32 in this embodiment).

[0030] The base 6 may have a function of moving the tray 10 in the vertical direction, and the free conveyor 7 may be arranged in multiple stages. In this case, it becomes possible to transport the tray 10 to the free conveyor 7 in multiple stages.

[0031] In this embodiment, the trays 10 are arranged in series in the first direction D1, and as shown in FIG. 2, the tray 10 can be moved from the base 6 onto the free conveyor 7 by pushing the tray 10 with the hook 4 of the drive device 3 engaged with the engagement recess 2f. At this time, the trays 10 already placed on the free conveyor 7 are also pushed and moved together. In addition, the tray 10 can be moved from the free conveyor 7 to the base 6 by pulling the tray 10 with the hook 4 of the drive device 3 engaged with the engagement recess 2f. Note that the tray 10 at the other end may be pushed from the free conveyor 7 to the base 6 by pushing one of the many trays 10 arranged in series at one end. In this case, the operation of pulling the tray 10 becomes unnecessary. The drive device 3 can be configured, for example, as a robot arm having the number of axes capable of the above-mentioned operation.

[0032] In addition, in FIG. 8, the short side direction of the tray 10 is the first direction D1, but the long side direction of the tray 10 may be the first direction D1.

[0033] 3. Method for manufacturing hydroponic tray 10 The hydroponic tray 10 can be formed by molding a parison using a split mold that can be opened and closed. The parison may be cylindrical or sheet-shaped. The resin constituting the parison is preferably a thermoplastic resin such as polyolefin, and examples of the polyolefin include low-density polyethylene, linear low-density polyethylene, high-density polyethylene, polypropylene, ethylene-propylene copolymer, and mixtures thereof. Examples of the molding method include blow molding, vacuum molding, and combinations thereof. During this molding, the inner surfaces of opposing parts of the parison (when the parison is composed of a pair of resin sheets, the inner surfaces of the pair of resin sheets) are welded to each other to form the welded parts 1b, 2e1 to 2e5. [Explanation of symbols]

[0034] 1: Bottom 1a: Recess 1b: Welded part 1c: Bottom inner wall 1d: 1st protrusion 1e: 2nd protrusion 2: Side 2a: Lower inner wall 2b: Intermediate inner wall 2c: Upper inner wall 2d: Recess 2d1: First recess 2d2: Second recess 2d3: 3rd recess 2d4: 4th recess 2e1: 1st weld part 2e2: 2nd welding part 2e3: 3rd welding part 2e4: 4th welding part 2e5: 5th welding part 2f: Engagement recess 2f1: Inner wall 2f2 :Outside wall 2g: Reinforcement recess 2h: part 2i : Part 2j :part 2j1 :Side wall 2k: Long side 2l:Short side 2m: corner 2n: Corner 2o: Hollow part 2p :Outer part 2q: part 2q1 :part 2q2 :part 3: Drive unit 4: Hook 4a: Bass 4b: Mounting part 4c:Tip 4d: Gap 5: Transport device 6: Base 7: Free conveyor 10: Hydroponic tray 10a:Inner wall 10b: Exterior wall 10c: Upper wall D1: 1st direction D2: Direction 2

Claims

1. A hydroponic tray comprising: The tray has a bottom and a side portion extending around the bottom, The tray includes an inner wall disposed on the inside of the tray and an outer wall disposed outside the inner wall, The side portion is provided with an engagement recess formed by recessing the outer wall upward, The engagement recess has an inner wall and an outer wall, the inner wall and the outer wall are a pair of side walls of the engagement recess, A tray, wherein the inner wall is disposed more inwardly of the tray than the outer wall.

2. 2. The tray of claim 1, A tray, wherein a first welded portion is provided on the inner wall, where the inner wall and the outer wall are welded to each other.

3. 2. The tray of claim 1, When the direction in which the inner wall and the outer wall face each other is defined as a first direction, The engagement recess extends in a second direction perpendicular to the first direction.

4. 2. The tray of claim 1, When the direction in which the inner wall and the outer wall face each other is defined as a first direction, The tray has a reinforcing recess extending in a first direction provided adjacent to the engagement recess.

5. 5. The tray of claim 4, A tray, wherein a second welding portion at which the inner wall and the outer wall are welded to each other is provided at the bottom of the reinforcing recess.

6. 5. The tray of claim 4, A pair of the reinforcing recesses are provided adjacent to the engagement recesses.

7. A method for transporting a tray according to any one of claims 1 to 6, comprising: The method comprises: moving a hook attached to a drive device in a direction toward the inner wall or the outer wall while engaging a tip of the hook with the engaging recess.

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