Dropping test method for fruit after storage, survey method of type-specific difference in damage resistance of fruit, and dropping test apparatus

Abstract

To provide a dropping test method which allows easy testing and evaluation of drop damage resistance of fruit that is easily damaged like strawberries, and to provide a dropping test apparatus to be used in the dropping test method.SOLUTION: Provided are a fruit dropping test method, and a fruit dropping test apparatus to be used in the fruit dropping test method. In the fruit dropping test method, damage generated in fruit due to impact when dropping the fruit is confirmed in order to test a resistance of the fruit against impact. In the fruit dropping test method, a disk made of a hard material is inserted between individual fruit and an upper surface of a hard plate on which the fruit is placed, and the hard plate is dropped while the fruit maintains the state of being in contact with the disk.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a drop test method that can easily test or evaluate the drop damage resistance of easily damaged fruits such as strawberries, and a drop test device used therein. [Background technology]

[0002] Strawberries account for nearly 20% of the total wholesale price of domestically produced fruits, and together with their wholesale price, they rank among the top major products. In addition, export volume has increased significantly due to demand in Hong Kong, Taiwan, and other countries. However, strawberry fruits are said to be easily damaged by dropping during distribution, and the deterioration of their appearance has led to complaints from delivery and export destinations. In addition, damage is said to accelerate quality deterioration, and may also lead to reduced shelf life. Therefore, there is a demand for a damage test system that can easily test or evaluate the damage susceptibility of strawberry fruits.

[0003] A drop tester that is normally used to evaluate the drop damage resistance of a product is designed to meet the standards of industrial products, and therefore has a drop height of 20 cm or more. In addition, a method and device described in Non-Patent Document 1 have been proposed for a drop test of strawberry fruits. Non-Patent Document 1 discloses that a tray filled with strawberry fruits was fixed between two aluminum plates from above and below, and then repeatedly dropped in this state to evaluate the damage to the strawberry fruits. [Prior art documents] [Non-patent literature]

[0004] [Non-Patent Document 1] Hiroaki Kitazawa et al., Journal of the Japan Society of Packaging Science, Vol. 21, No. 2 (2012), pp. 125-132 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the impact of a drop from a height of 20 cm or more in conventional product drop tests is too strong for strawberry fruits, which are easily damaged. In addition, conventional drop test machines for industrial products are very expensive, and there is a problem of high introduction costs.

[0006] In addition, the contact area between the bottom and the strawberry fruit when dropped has a large effect on the strength of the force transmitted to the fruit when impacted, but when fruits are packed in a tray and dropped, the contact area between the bottom and the fruit is not constant and the impact on the fruit is random, making it difficult to compare the drop damage resistance of the fruit. The purpose of the conventional method was to confirm the cushioning effect of the packaging material, and it was not suitable for testing or evaluating the drop damage resistance of fruit.

[0007] Therefore, an object of the present invention is to provide a drop test method and a drop test device used therein that can easily test or evaluate the drop damage resistance of easily damaged fruits such as strawberries. [Means for solving the problem]

[0008] In order to solve the above problems, the present invention provides a fruit drop test method for checking damage caused to fruit by impact when the fruit is dropped in order to test the impact resistance of the fruit, characterized in that a disk made of hard wood is sandwiched between each fruit and the upper surface of a hard plate on which the fruit is placed, and the hard plate is dropped while the fruit is maintained in contact with the disk.

[0009] Here, when the hard plate is dropped, a strip may be wrapped around and fixed to the fruit and the disk, so that the fruit can be maintained in contact with the disk.

[0010] Alternatively, when the hard plate is dropped, the disk may be sandwiched between the fruit and the upper surface of the hard plate, and a strip may be wrapped around and secured to the fruit and the hard plate, thereby maintaining the fruit in contact with the disk.

[0011] The disk may also have a diameter of 5 to 15 mm and a thickness of 0.5 to 3 mm.

[0012] The present invention provides a fruit drop test device used in the above-mentioned method, comprising a frame consisting of front, rear, left and right side walls, a case for storing fruit arranged within the frame, and a pair of blades provided on the inside of both left and right ends of the frame for dropping the case by opening and closing the case, the case having a hard plate on its bottom surface for placing the fruit on and a disk made of hard material arranged on the upper surface of the hard plate, the pair of blades being rectangular plate-shaped and pivoted on the front and rear side walls with the long side direction as the axial direction, the blades being fixed horizontally when closed and supporting the case from below at their inner ends, while the blades are released when opened and the case falls by its own weight.

[0013] Here, the disk may have a convex portion on the surface that contacts the hard plate, and the upper surface of the hard plate may have a concave portion that fits with the convex portion of the disk to prevent the disk from shifting in the horizontal direction. Also, the hard plate may have a band-shaped body for fixing the fruit in a state where the disk is sandwiched between the fruit and the upper surface of the hard plate. Effect of the Invention

[0014] According to the fruit drop test method of the present invention, a hard disk is sandwiched between each fruit and the upper surface of the hard plate on which the fruit is placed, and the hard plate is dropped while the fruit is kept in contact with the disk, so that the area of ​​impact applied to each fruit when dropped is equal to the size of the disk sandwiched between the fruit and the upper surface of the hard plate. Since the area of ​​impact application has a large effect on the strength of the impact applied to the fruit, by keeping the area of ​​impact application constant, the strength of the impact applied to the fruit can also be made constant, which makes it possible to compare the drop damage resistance (fragility) of different fruits.

[0015] In addition, when the hard plate is dropped, a strip is wrapped around and fixed to the fruit and the disk, or the fruit and the hard plate, so that the hard plate can be dropped in a simple manner without damaging the fruit and while maintaining the fruit in contact with the disk.

[0016] Furthermore, the fruit drop test device of the present invention includes a frame consisting of front, rear, left and right side walls, a case for storing fruit arranged in the frame, and a pair of blades provided inside the left and right ends of the frame, which drop the case by opening and closing, and the pair of blades are rectangular plates, each of which is supported on the front and rear side walls with the long side direction as the axial direction, and is fixed horizontally when closed and supports the case from below at the inner end, while being released when opened so that the case falls by its own weight, making it possible to perform drop tests with a device that is simpler, smaller and lighter than conventional devices. Therefore, the introduction cost of the device can be reduced, and the device can be carried around, allowing drop tests to be performed anywhere. [Brief description of the drawings]

[0017] [Figure 1] 1 is a front view showing the configuration of an example of a drop test device according to the present embodiment, where (A) shows the "closed" state (when the blade is fixed) and (B) shows the "open" state (when the blade is released). [Diagram 2] FIG. 2 is a left side view showing the configuration of an embodiment of a drop test device (when the blade portion is fixed). [Diagram 3] 1A is a partial enlarged view for explaining the configuration of a blade opening / closing device 5a in the embodiment, in which (A) is a front view showing the "open" state (when the blade is released), (B) is a side cross-sectional view showing the "open" state (when the blade is released), and (C) is a side cross-sectional view showing the "closed" state (when the blade is fixed). [Figure 4]1A is a top view showing a state in which a disk is sandwiched between a fruit and a hard plate in a case, and FIG. 1B is a perspective view showing a state in which a band is wrapped around the fruit and the disk, for explaining an example of the drop test method according to the present embodiment. [Diagram 5] 11A and 11B are diagrams for explaining the configuration of a hard plate, a disk, and a strip in another embodiment, in which (A) is a top view, (B) is a partial cross-sectional view along the XX axis showing a method for fixing a disk to a hard plate, (C) is a cross-sectional view along the XX axis, and (D) is a front view showing a state in which the strip is wrapped around the fruit and the hard plate. [Figure 6] FIG. 11 is a partial cross-sectional view for explaining the configuration of a hard plate and a disk in still another embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] Hereinafter, the fruit drop test method of this embodiment will be described with reference to the drawings. FIG. 1 is a front view showing the configuration of an embodiment of a fruit drop test device 1 used in this method, and FIG. 2 is a left side view showing the configuration of the embodiment. FIG. 3 is a partially enlarged view showing the configuration of a blade opening and closing device 5a of the embodiment. FIG. 4 is a diagram for explaining an embodiment of the drop test method of this embodiment. FIG. 4(A) is a plan view of the case 3 showing a state in which a fruit F is placed on the upper surface of the hard plate 32, and FIG. 4(B) is a perspective view showing a state in which a strip 36 is wrapped around and fixed to the fruit F and the disk 33. FIG. 5 is a diagram for explaining the configurations of the hard plate 321, the disk 331, and the strip 361 in another embodiment. FIG. 5(A) is a top view, FIG. 5(B) is a partial XX-axis cross-sectional view showing a method of fixing the disk 331 to the hard plate 321, (C) is a XX-axis cross-sectional view, and (D) is a front view showing a state in which the strip 361 is wrapped around and fixed to the fruit F and the hard plate 321. FIG. 6 is a partial cross-sectional view for explaining the configuration of a hard plate and a disk in still another embodiment.

[0019] The fruit drop test method of this embodiment is a fruit drop test method that checks the damage caused to the fruit by the impact when the fruit is dropped in order to examine the impact resistance of the fruit.

[0020] The target fruit is not limited to strawberry fruit exemplified below, but can be applied to various fruits including easily damaged fruits such as peaches and cherries.

[0021] The fruit is placed on the upper surface of the hard plate 32. The hard plate 32, which is the component most likely to receive an impact during a drop test, is preferably made of a metal that is durable and does not easily deteriorate over time, and specific examples include aluminum and stainless steel, but are not limited to these.

[0022] Then, a disk 33 is sandwiched between each fruit and the upper surface of the hard plate 32 on which the fruit is placed. This disk 33 is interposed between the upper surface of the hard plate 32 and the fruit, in order to quantitatively transmit the impact transmitted from the hard plate 32 when the fruit is dropped to the fruit.

[0023] That is, if fruit is placed directly on the upper surface of the hard plate 32 without the interposition of the disk 33, the contact area (area to which impact is applied) between the hard plate 32 and the fruit will not be constant, and the strength of the impact applied to the fruit when dropped will be random (non-quantitative). On the other hand, by interposing the disk 33 between the upper surface of the hard plate 32 and the fruit, and limiting the area to which impact is applied when dropped to the contact area with the disk 33, it is possible to control the strength of the impact applied to the fruit to a constant level. By keeping the strength of the impact constant, the degree of damage the fruit receives from the impact will also be constant, making it possible to compare the drop damage resistance of different fruits.

[0024] The disk 33 is a thin disk made of a hard material such as aluminum or other metal. The size of the disk 33 is not particularly limited, but should be such that the entire disk can contact the surface of the fruit, depending on the shape of the fruit to be tested. In order to make the strength of the impact applied to each fruit when dropped constant, the disks 33 used for each fruit to be tested at the same time are all approximately the same. Specifically, the diameter of the disk 33 may be, for example, 5 to 15 mm. The thickness of the disk 33 may be, for example, 0.5 to 3 mm.

[0025] The disk 33 may be fixed at a predetermined position on the hard plate 32. Specifically, as shown in Fig. 5 and Fig. 6, a convex portion 332 provided on the surface of the disk 331 that contacts the hard plate 321 is fitted into a concave portion 333 formed at a predetermined position on the upper surface of the hard plate 321 so as to fit with the convex portion 332, thereby preventing the disk 331 from shifting in the horizontal direction. At this time, the height of the portion of the disk 331 protruding from the upper surface of the hard plate 321 may be about 0.5 mm to 3 mm. The disk may be fixed by using adhesive, tape, magnetic force, or the like in addition to the above.

[0026] In addition, multiple fruits can be placed on the upper surface of the hard plate 32, but in that case, it is necessary to prevent the fruits from contacting each other. If the fruits collide with each other due to the impact of the fall, the impact is applied from other than the contact surface with the disk 33, so the strength of the impact applied to each fruit cannot be made constant, making it difficult to compare the drop damage resistance of different fruits. Specifically, as shown in Figure 4, by storing each fruit individually in each compartment separated by a partition plate 35, it is possible to prevent the individual fruits from contacting each other.

[0027] Next, the hard plate 32 is allowed to fall freely with the fruit placed on the upper surface, so that the impact of the fall is applied to the fruit. The impact of the fall of the hard plate 32 is transmitted to the fruit via the disk 33.

[0028] Here, the height from which the hard plate 32 is dropped is not limited as long as the degree of damage between fruits can be compared, and can be changed depending on the perishability of the target fruits, but can usually be 3 to 15 cm, or even 4 to 7 cm.

[0029] In this embodiment, the hard plate 32 on which the fruit is placed can be dropped repeatedly. Since the impact applied to the fruit in a single drop is small, it may be difficult to compare the presence or absence and the degree of damage between fruits. In that case, the strength of the impact applied to the fruit can be increased by increasing the drop height as described above, but this requires a change in the design of the drop test device 1. Therefore, by increasing the number of drops and repeatedly applying impact to the fruit, damage due to accumulated fatigue can be generated, making it easier to compare damage between fruits. The number of drops is not particularly limited and can be changed depending on the fragility of the target fruit, but it can usually be 1 to 9 times, or even 1 to 6 times.

[0030] The surface on which the ball is dropped may be a flat surface, or obstacles such as blocks may be placed on the surface. When obstacles are placed on the surface, the strength of the impact applied when the ball is dropped can be changed by changing the hardness of the obstacles.

[0031] In this embodiment, it is necessary to drop the hard plate 32 while keeping the fruit in contact with the disk 33. This is because if the fruit is not in contact with the disk 33, the strength of the impact applied to the fruit when it is dropped cannot be made constant. Normally, if the fruit is not fixed, in the case of a fruit with a curved or irregular surface shape, the fruit will roll on the upper surface of the hard plate 32 and will not be able to maintain contact with the disk 33.

[0032] The means for maintaining the fruit and the disk 33 in contact with each other is not particularly limited, but may be, for example, a method in which a strip 36 such as a piece of paper is wrapped around the fruit and the disk 33 to secure them as shown in Fig. 4. Alternatively, as shown in Fig. 5, a small hard plate 321 corresponding to each fruit may be used, and a strip 361 may be wrapped around the fruit and the hard plate 321 to secure them.

[0033] The belt 36 is desirably made of a flexible material such as resin, paper, or cloth so that it can be fixed to the fruit without damaging it. More preferably, as shown in Fig. 5, the belt 361 can be configured with hook and loop fasteners (362, 363) on both ends. With this configuration, the hook and loop fasteners 362 and 363 can be closed together to easily fix the fruit, and it is also economical because it can be reused.

[0034] In this way, hard plate 32 is dropped while the fruit is kept in contact with disk 33, and then the presence or absence of damage to the fruit due to the impact and the extent of the damage are checked. In this embodiment, since the strength of the impact applied to the fruit by the drop is constant, it is possible to compare the fragility (resistance to drop damage) of fruits by comparing the extent of the damage between fruits.

[0035] Next, an embodiment of the fruit drop test device 1 used in the above drop test method will be described with reference to the drawings.

[0036] As shown in FIGS. 1 and 2, the drop test apparatus 1 according to this embodiment is mainly composed of a frame 2, a case 3 arranged inside the frame 2, and a pair of blade portions 4a, 4b provided on the inside of both the left and right ends of the frame 2.

[0037] The frame 2 is configured in a rectangular cylindrical shape consisting of front, rear, left and right side walls 21, 21, 22, 22. The frame 2 may have a floor, but does not have a ceiling because this would interfere with tasks such as placing fruit in the case 3. Furthermore, the frame 2 is preferably configured from a transparent or semi-transparent material such as acrylic resin so that the drop test can be easily observed.

[0038] The pair of left and right blades 4a, 4b open and close to drop the case 3. The blades 4a, 4b are rectangular plate-shaped members, and are supported by shafts 41, 41 on the front and rear side walls 21, 21 of the frame 2 with their long sides extending in the axial direction.

[0039] 1(A), in the "closed" state of the opening and closing operation, the blades 4a, 4b are fixed horizontally, and their inner ends 42, 42 are configured to support the case 3 from below. That is, the shaft 41 that supports the blades 4a, 4b is slightly closer to the outside (side wall 22 side) than the center of the short side of the blades 4a, 4b, and the center of gravity of the blades 4a, 4b is closer to the inside than the shaft 41. Therefore, by locking the outer ends 43, 43 from above, the rotation of the blades 4a, 4b can be stopped and they can be fixed horizontally.

[0040] 1(B), in the "opening" stage of the opening / closing operation, the blades 4a, 4b are released (released) from being locked from above on the outer ends 43, 43, and the blades 4a, 4b become rotatable. Then, the blades 4a, 4b rotate so that the inside where the center of gravity is located faces downward, and the case 3 supported from below by the inner ends 42, 42 falls under its own weight.

[0041] In addition, in the blade portions 4a and 4b, the length in the short side direction from the axis 41 to the inner end portion 42 is approximately equal to the installation height of the axis 41 on the side wall 21, which is the drop height of the case 3, but is shorter than this, so as not to interfere with the opening and closing operation.

[0042] As mentioned above, the height to which the case 3 falls due to the release of the blade portions 4a, 4b is not limited as long as the degree of damage between fruits can be compared, and can be changed depending on the perishability of the target fruit, but can usually be 3 to 15 cm, or even 4 to 7 cm.

[0043] As described above, the drop surface may be a flat surface, or obstacles such as blocks may be placed on the surface.

[0044] The case 3 is disposed inside the frame 2, and is intended to house the fruit that is the subject of the drop test. The case 3 is provided with a hard plate 32 on the bottom surface for placing the fruit thereon. The hard plate 32 is as described above. The above-mentioned disks 33 are disposed on the upper surface of the hard plate 32. The number of disks 33 disposed on the upper surface of the hard plate 32 is the same as the number of fruits to be placed on the upper surface of the hard plate 32.

[0045] As described above, the disk 33 may be fixed at a predetermined position on the hard plate 32. Specifically, as shown in Fig. 5 and Fig. 6, a convex portion 332 provided on the surface of the disk 331 that contacts the hard plate 321 is fitted into a concave portion 333 formed at a predetermined position on the upper surface of the hard plate 321 so as to fit with the convex portion 332, thereby preventing the disk 331 from shifting in the horizontal direction. At this time, the height of the portion of the disk 331 protruding from the upper surface of the hard plate 321 may be about 0.5 mm to 3 mm. In addition to the above, the disk may be fixed by using an adhesive, a tape, a magnetic force, or the like.

[0046] When multiple fruits are placed on the upper surface of the hard plate 32, as mentioned above, in order to prevent the fruits from coming into contact with each other, the inside of the case 3 can be divided, for example, by a partition plate 35, and each compartment can accommodate one fruit F (see Figure 4(A)).

[0047] As described above, the case 3 may be provided with a strip 36, such as a piece of paper, as a means for maintaining the fruit and the disc 33 in contact when dropped. This strip 36 may be used, for example, to wrap around the fruit F and the disc 33 to secure them (see FIG. 4). Alternatively, as shown in FIG. 5, in the case where a small hard plate 321 corresponding to each individual fruit is used, the strip 361 may be provided on the hard plate 321. This strip 361 may be used, for example, to wrap around the fruit F and the hard plate 321 to secure them.

[0048] Fixing the fruits with the band 36 in this way also makes it possible to prevent the fruits from coming into contact with each other. As mentioned above, the band 36 is preferably made of a flexible material. More preferably, as shown in FIG. 5, the band 361 can be configured with hook and loop fasteners (362, 363) on both ends. With this configuration, the hook and loop fasteners 362 and 363 can be closed together to easily fix the fruits, and the fastener can be reused, making it economical.

[0049] As described above, in the fruit drop test device 1 according to the present embodiment, the fruit drop test can be performed by a simple operation of opening and closing (fixing and releasing) the blade parts 4a and 4b. Therefore, the operation of repeatedly dropping the fruit can be easily performed, and the structure is particularly suitable for repeated drop tests from a relatively low height for easily damaged fruits.

[0050] Next, a method of using and an operation of the fruit drop test device 1 according to the present embodiment will be described.

[0051] (1) First, as shown in Fig. 4, a target fruit F is placed on the upper surface of the hard plate 32 of the case 3. At this time, a disk 33 is sandwiched between each fruit F and the upper surface of the hard plate 32. Also, in order to keep the fruit F in contact with the disk 33 when it falls, the fruit F and the disk 33 or the hard plate 32 are fixed by wrapping a strip 36, such as a piece of paper, around them.

[0052] By placing a disk 33 between the upper surface of the hard plate 32 and the fruit F and limiting the area to which the impact is applied when dropped to the contact area with the disk 33, it is possible to control the strength of the impact applied to the fruit at a constant level. By keeping the strength of the impact constant, the degree of damage the fruit receives from the impact also becomes constant, making it possible to compare the drop damage resistance of different fruits.

[0053] In addition, by fixing the fruit F to the disk 33 or the hard plate 32, it is possible to prevent the fruit F from rolling on the upper surface of the hard plate 32 and becoming separated from the disk 33.

[0054] (2) Next, the outer ends 43, 43 of the wings 4a, 4b provided on the inside of both the left and right ends of the frame 2 are engaged from above, thereby fixing the wings 4a, 4b horizontally (see FIG. 1(A)).

[0055] The blade portions 4a, 4b are supported by shafts 41, 41 on the front and rear side walls 21, 21 of the frame 2. The shaft 41 is slightly closer to the outside (side wall 22 side) than the center in the short side direction of the blade portions 4a, 4b, and the center of gravity of the blade portions 4a, 4b is closer to the inside than the shaft 41. Therefore, by engaging the outer ends 43, 43 from above and stopping the rotation of the blade portions 4a, 4b, it is possible to fix the blade portions 4a, 4b horizontally.

[0056] (3) Next, the left and right ends of the bottom surface of the case 3 are placed on the inner ends 42, 42 of the blade portions 4a, 4b that are fixed horizontally so as to be hooked thereon (see FIG. 1(A)).

[0057] (4) Furthermore, as shown in FIG. 1B, by releasing the engagement from above with the outer ends 43, 43 of the wings 4a, 4b, the case 3 is allowed to fall by its own weight.

[0058] That is, by releasing (opening) the fixedness of the blades 4a, 4b, the blades 4a, 4b become rotatable, and the blades 4a, 4b rotate so that the inside where the center of gravity is located is downward (i.e., so that the inside end 42 approaches the side wall 22). Then, the case 3 that was supported from below by the inside end 42, 42 of the blades 4a, 4b can be dropped by its own weight.

[0059] In the blade portions 4a, 4b, the length in the short side direction from the axis 41 to the inner end 42 is approximately equal to but shorter than the installation height of the axis 41 on the side wall 21, which is the drop height of the case 3. In this embodiment, the drop height can be changed depending on the perishability of the target fruit, but is usually 3 to 15 cm. This makes it possible to make the entire device smaller and lighter.

[0060] If no damage to the fruit is confirmed after one drop, multiple drop tests can be performed by repeating steps (2) to (4) above. This is because repeated drops can cause damage to the fruit due to accumulated fatigue.

[0061] (5) Finally, the fruit F is retrieved from the dropped case 3, and the presence or absence of damage to the fruit due to the impact and the extent of the damage are confirmed. Damage can be determined if deformation or scratches have occurred on the fruit due to pressure.

[0062] In this embodiment, the area where the impact is applied during a drop can be made constant by interposing the disk 33 between the fruit and the hard plate 32, and therefore the strength of the impact applied to the fruit becomes constant. Therefore, by comparing the presence or absence and size of damage between fruits, it is possible to compare the fragility (resistance to drop damage) between fruits. EXAMPLES

[0063] The present embodiment will now be described in detail with reference to examples.

[0064] Example 1 As shown in Figures 1 and 2, the fruit drop test apparatus 1 comprises a frame 2, a case 3 arranged inside the frame 2, a pair of blade portions 4a, 4b provided on the inside of both left and right ends of the frame 2, and a pair of blade portion opening and closing devices 5a, 5b provided on both left and right ends of the frame 2.

[0065] The frame 2 is a square cylinder having a width of 255 mm, a depth of 210 mm, and a height of 125 mm, and is composed of front, rear, left and right side walls 21, 21, 22, and 22. In addition, the frame 2 is made of transparent acrylic resin, so that the state inside can be observed.

[0066] At a position 58 mm high near the center of the long sides of the left and right side walls 22, 22, holes are provided for inserting the pistons 52 of the blade opening / closing devices 5a, 5b into the frame 2. In addition, at positions slightly lower on the left and right of the holes for inserting the pistons 52, a pair of holes for screwing the blade opening / closing devices 5a, 5b are provided.

[0067] The pair of left and right blades 4a, 4b are rectangular plate-shaped members measuring 46 mm in length, 187 mm in width, and 5 mm in thickness. The blades 4a, 4b are supported by shafts 41 at positions 47 mm high and 24 mm toward the center on the front and rear side walls 21, 21 of the frame 2, with the long side direction being the axial direction.

[0068] 1(A), the shaft 41 that supports the blades 4a, 4b in the long side direction is slightly closer to the outside (side wall 22 side) than the center of the short side direction of the blades 4a, 4b. Specifically, the length from the shaft 41 to the inner end 42 in the short side direction is approximately twice the length from the shaft 41 to the outer end 43. Therefore, the center of gravity of the blades 4a, 4b is closer to the inside than the shaft 41.

[0069] The pair of left and right blade opening / closing devices 5a, 5b are for dropping the cases 3 containing fruit by opening and closing the blades 4a, 4b, respectively. As shown in Fig. 2, the blade opening / closing devices 5a, 5b are attached to the outside near the center in the long side direction of the left and right side walls 22, 22 of the frame 2. As shown in Fig. 3, the blade opening / closing devices 5a, 5b are mainly composed of a plate 51, a piston 52, a coil spring 53, and a hook 54.

[0070] The plate 51 is a rectangular plate member with a length of 38 mm, a width of 82 mm, and a thickness of 10 mm. A hole through which the piston 52 is inserted horizontally is provided in the upper part of the plate 51 near the center of the long side. In addition, a pair of spacers 511, 511 are attached and fixed to the left and right ends of the plate 51 on the frame 2 side. This ensures a space between the spacers 511, 511 for rotatably attaching the hook 54. The spacer 511 is a rectangular plate with a length of 38 mm, a width of 12 mm, and a thickness of 5 mm.

[0071] A pair of holes that penetrate horizontally through the plate 51 and the spacer 511 are provided at the left and right ends of the plate 51, slightly below the holes through which the pistons 52 are inserted. These holes are for inserting screws 56, 56 that fix the blade opening / closing devices 5a, 5b to the left and right side walls 22, 22.

[0072] 3(B) and (C), the piston 52 is a generally cylindrical stainless steel member having a diameter of 8 mm and a length of 40 mm, which is provided so as to horizontally penetrate the plate 51 and the left and right side walls 22. A groove 523 for fitting the notch 541 of the hook 54 is engraved in the circumferential direction at approximately the center in the longitudinal direction of the piston 52. Furthermore, an inner tip portion 521 and an outer tip portion 522, which are disks having a diameter slightly larger than that of the piston 52, are joined to both ends of the piston 52, respectively.

[0073] A coil spring 53 is wound around the outside of the piston 52 (the side opposite to the frame 2), and the coil spring 53 is sandwiched between the outer tip portion 522 and the outer surface of the plate 51. When the blade portions 4a and 4b are fixed, the piston 52 is fixed in the position shown in FIG. 3(C), and the coil spring 53 is compressed between the outer tip portion 522 and the outer surface of the plate 51.

[0074] At this time, the inner tip 521 protrudes inside the frame 2 and engages the upper surfaces of the outer ends 43 of the blades 4a, 4b, thereby fixing the blades 4a, 4b horizontally. That is, since the center of gravity of the blades 4a, 4b is closer to the inside than the shaft 41, the blades 4a, 4b rotate so that the inner ends 42 are downward when released. Therefore, the inner tip 521 of the piston 52 engages the upper surfaces of the outer ends 43 of the blades 4a, 4b to stop the rotation of the blades 4a, 4b, thereby fixing the blades 4a, 4b horizontally.

[0075] On the other hand, when the blade portions 4a, 4b are released, the coil spring 53 biases the piston 52 so as to pull it outward from the frame 2 (i.e., in the direction of the arrow in FIG. 3(B)). Since the diameter of the inner tip portion 521 of the piston 52 is larger than the diameter of the hole provided in the plate 51 through which the piston 52 passes, the entire piston 52 biased by the coil spring 53 does not jump out of the hole.

[0076] The hook 54 is an iron member formed into a thin rectangular plate of approximately 60 mm in length and 10 mm in width, and is used to fix the inner tip 521 of the piston 52 at a position protruding inwardly from the frame 2, or to release this fixation.

[0077] 2 and 3, the hook 54 is journaled slightly toward the rear of the center on the frame 2 side of the plate 51 so that both the upper and lower ends protrude from the plate 51. The hook 54 is journaled to the frame 2 by a pin 55 at a position slightly toward the lower center.

[0078] A substantially semicircular notch 541 is provided in the hook 54 at a position corresponding to the piston 52. When the blade portions 4a, 4b are fixed, the upper end of the hook 54 is pulled by a coil spring 58 so that the notch 541 fits into the groove 523 of the piston 52, as shown in Figures 2 and 3(C). One end of the coil spring 58 is hooked into a hole provided in the upper end of the hook 54, and the other end is fixed to a screw 57 that is screwed into the upper end face of the plate 51 near the front.

[0079] The lower end of the hook 54 is screwed with an inner wire 543 connected to the switch S by a screw 542. The inner wire 543 is inserted through an outer wire 544, and the outer wire 544 passes through an insertion hole of a wire guide portion 512 provided at the lower end of the plate 51 and is connected to the switch S (not shown).

[0080] The switch S controls the opening and closing of the blades 4a and 4b. When the switch S is open, as shown in FIG. 3(A), the inner wire 543 is pulled, causing the lower end of the hook 54 to rotate in the direction of the arrow. Next, the upper end of the hook 54 rotates in the direction of the arrow by the principle of leverage, and the engagement between the notch 541 and the groove 523 of the piston 52 is released. Then, the piston 52 is urged by the coil spring 53, and the inner tip 521 that has been engaging the outer end 43 of the blades 4a and 4b from above moves from the position shown in FIG. 3(C) to the position shown in FIG. 3(B). As a result, the inner tip 521 that has been engaging the outer end 43 of the blades 4a and 4b from above retracts toward the left and right side walls 22, and the blades 4a and 4b are released from the fixed state (released), and the blades 4a and 4b become rotatable.

[0081] On the other hand, when the switch S is closed, the inner wire 543 is relaxed, and the upper end of the hook 54 is pulled toward the piston 52 by the elastic force of the coil spring 58, so that the notch 541 can fit into the groove 523. At that time, the piston 52 of the blade opening / closing device 5a is pushed inwardly of the frame 2 by hand, so that the notch 541 of the hook 54 fits into the groove 523 of the piston 52.

[0082] The case 3 is disposed inside the frame 2, and is box-shaped with a length of 115 mm, a width of 175 mm, and a height of 35 mm, and is mainly composed of a storage section 31 and a lid 34, as shown in Fig. 4. The storage section 31 has a hard plate 32 as a bottom surface, side walls on the front, back, left, and right, and three partition plates 35, ... that divide the interior into six compartments. The lid 34 fits into the storage section 31 and prevents fruit from flying out of the storage section 31 if it is dropped. Also, like the frame 2, the case 3 is made of transparent acrylic resin except for the hard plate 32, so that the inside can be observed.

[0083] The hard plate 32 is a rectangular thin plate made of aluminum. On the upper surface of the hard plate 32, one aluminum disk 33 is arranged for each compartment. Also, one fruit F is placed on the upper surface of the hard plate 32 for each compartment. As shown in Fig. 4(A), by storing one fruit F in each compartment separated by a partition plate 35, it is possible to prevent random damage caused by the fruits colliding with each other when they fall.

[0084] The method of the drop test for fruit using the above drop test apparatus 1 is as follows.

[0085] (1) First, strawberry fruits F (three each of varieties A and B) to be tested are placed in the case 3. That is, one strawberry fruit F is placed in each of the six compartments separated by partitions 35 in the storage section 31 (see FIG. 4(A)). To prevent the strawberry fruits F from rolling away from the disk 33 during the test, a strip 36 of a long, thin piece of paper with a width of about 10 mm is wrapped around the fruits F and the disk 33 to secure them (see FIG. 4(B)). After that, the lid 34 is fitted onto the storage section 31 containing the fruits F.

[0086] (2) Next, with switch S in the "closed" position, push piston 52 of blade opening / closing device 5a inwardly of frame 2 by hand until notch 541 of hook 54 fits into groove 523 of piston 52. Since inner wire 543 is in a relaxed state and the upper end of hook 54 is pulled toward piston 52 by the elastic force of coil spring 58, piston 52 is fixed in the position shown in Fig. 4(C). Next, the same operation is performed for blade opening / closing device 5b.

[0087] (3) After the pistons 52 of the blade opening / closing devices 5a, 5b are fixed in a protruding state to the inside of the frame 2 as described above, the upper surfaces of the inner ends 42 of the blades 4a, 4b are engaged with the inner tip portions 521 of the pistons 52, thereby fixing the blades 4a, 4b horizontally (see FIG. 1(A)).

[0088] (4) The left and right ends of the underside of the case 3 containing the fruit in (1) are placed on the inner ends 42, 42 of the fins 4a, 4b fixed horizontally as described above so as to be hooked onto them (see FIG. 1(A)).

[0089] (5) Next, switch S is switched from "closed" to "open" to release (disengage) the fixed blade portions 4a and 4b as shown in Fig. 1(B). That is, by turning switch S to "open" and pulling inner wire 543, the upper end of hook 54 rotates in the direction of the arrow by the principle of leverage, and the engagement between notch 541 and groove 523 of piston 52 is released. Then, piston 52 is urged by the elastic force of coil spring 53 and moves from the position in Fig. 3(C) to the position in Fig. 3(B), and blade portions 4a and 4b become rotatable.

[0090] (6) As a result of the above, the case 3 falls under its own weight. The falling height is approximately 50 mm, which is roughly equal to the installation height of the shaft 41 on the side wall 21. As the case falls, the strawberry fruit F receives a certain amount of impact from the contact surface with the disk 33. Furthermore, by repeating the steps (2) to (5) twice, damage due to fatigue accumulation occurs in the strawberry fruit F.

[0091] (7) Finally, strawberry fruit F is retrieved from case 3 where it was dropped, and the presence or absence of damage to the fruit due to the impact and the extent of the damage are confirmed. As a result, in all samples of variety A, no visible damage occurred, whereas in all samples of variety B, dents and discoloration were confirmed in the skin on the surface that came into contact with disk 33. This indicates that variety B is less resistant to drop damage (more fragile) than variety A.

[0092] (8) In addition, when the drop tests (1) to (7) were carried out using strawberry fruits of the same varieties A and B as the samples used above that had been refrigerated (5°C, 1 day), the same results were obtained. This demonstrated that the drop test method can be applied to fruits that have been refrigerated.

[0093] Example 2 Next, the configuration of another embodiment of the hard plate, disk, and strip used in the fruit drop test apparatus 1 will be described with reference to Fig. 5. In Fig. 5, (A) is a top view, (B) is a partial XX-axis cross-sectional view showing a method of fixing the disk to the hard plate, (C) is a XX-axis cross-sectional view, and (D) is a front view showing the fruit and the hard plate wrapped with the strip. In this embodiment, the description of the same configuration as the drop test apparatus 1 described above may be omitted.

[0094] In another embodiment shown in Fig. 5, hard plate 321 is a substantially square stainless steel thin plate with a side length of about 50 mm and a thickness of 3 mm. A recess 333 is formed near the center of the upper surface of this hard plate 321 so as to fit with a protrusion 332 provided on the surface of disk 331 that comes into contact with hard plate 321, as shown in Fig. 5(B). Disk 331 is an aluminum disk with a diameter of 10 mm and a thickness of 2 mm. A protrusion 332 with a height of 0.5 mm is provided near the center of the surface of disk 331 that comes into contact with hard plate 321.

[0095] 5(B), in this embodiment, recess 333 has a two-stage recess structure. That is, recess 333 has a two-stage recess structure in which a second recess having a shape that fits with protrusion 332 is formed below a first recess having an aperture approximately equal to the diameter of disk 331. When protrusion 332 and recess 333 are fitted together, the height of the portion of disk 331 protruding from the upper surface of hard plate 321 is 1.5 mm.

[0096] By fitting the convex portion 332 of the disk 331 thus configured into the concave portion 333 of the hard plate 321, it is possible to prevent the disk 331 from shifting horizontally, and it is also possible to easily remove the disk 331 fixed onto the hard plate 321.

[0097] 5(A) and (C), a strip 361 is attached and fixed to the underside of the hard plate 321. The strip 361 is made of a flexible resin tape with a width of about 30 mm and a length of about 150 mm, and the hard plate 321 is fixed near the center of the strip 361. A hook portion 362 of a hook-and-loop fastener is provided on the upper or lower surface of one end of the strip 361. Furthermore, a loop portion 363 of a hook-and-loop fastener is provided on the surface of the other end of the strip 361 that is vertically opposite to the surface on which the hook portion 362 is provided.

[0098] 5(D), the band-shaped body 361 configured in this manner can be easily fixed by wrapping the band-shaped body 361 around the fruit F and the hard plate 321 by closing the hook portions 362 and loop portions 363 at both ends. Also, by adjusting the position at which the hook portions 362 and loop portions 363 are closed according to the size of the fruit F, the fruit F can be securely fixed without being damaged.

[0099] One or more units each consisting of the hard plate 321, disc 331 and strip 361 having such a configuration are arranged inside the case 3. Specifically, the disc 331 is fixed at a predetermined position on the upper surface of the hard plate 321, and the fruit F to be tested is placed on the disc 331. With the strip 361 wrapped around the fruit F and the hard plate 321 and fixed, the unit is arranged on the bottom surface of the storage section 31 of the case 3.

[0100] In this way, by configuring the units, each with one fruit F fixed to the center of the small hard plate 321, to be able to be separated individually, the work of fixing the fruit F with the strip 361 can be easily performed, and even without the partition plate 35, the fruits can be prevented from colliding with each other during testing, and the case 3 can also be made lighter.

[0101] Example 3 Next, the configuration of yet another embodiment of the hard plate and disk used in the fruit drop test apparatus 1 will be described with reference to Fig. 6. Fig. 6 is a partial cross-sectional view showing a method for fixing the disk to the hard plate. In this embodiment, the description of the same configuration as the drop test apparatus 1 described above may be omitted.

[0102] In yet another embodiment shown in Fig. 6, hard plate 321 is a substantially square stainless steel thin plate with a side length of about 50 mm and a thickness of 3 mm. A recess 333 is formed near the center of the upper surface of this hard plate 321 so as to fit with a protrusion 332 provided on the surface of disk 331 that comes into contact with hard plate 321. Disk 331 is an aluminum disk with a diameter of 10 mm and a thickness of 2 mm. A protrusion 332 with a height of 0.5 mm is provided near the center of the surface of disk 331 that comes into contact with hard plate 321.

[0103] 6, in this embodiment, the recess 333 is formed as a one-step recess structure shaped to fit with the protrusion 332. When the protrusion 332 and the recess 333 are fitted together, the height of the portion of the disk 331 protruding from the upper surface of the hard plate 321 is 1.5 mm.

[0104] By fitting the convex portion 332 of the disk 331 thus configured into the concave portion 333 of the hard plate 321, it is possible to prevent the disk 331 from shifting horizontally, and it is also possible to easily remove the disk 331 fixed onto the hard plate 321.

[0105] By adopting such a configuration, it is possible to prepare disks of various sizes in which the shape of the convex portion 332 is the same and only the diameter of the disk 331 is changed, and it becomes easy to replace the disk with the appropriate size depending on the size of the fruit F.

[0106] Although not shown in FIG. 6, a strip-shaped body 361 as described in the second embodiment may be attached and fixed to the underside of the hard plate 321.

[0107] The above describes in detail the embodiment and examples of the present invention with reference to the drawings. However, the specific configurations are not limited to these, and design changes that do not deviate from the gist of the present invention are included in the present invention.

[0108] For example, in the above embodiment, a drop test method for strawberry fruit and a drop test device used therein are described, but the present invention is not limited to this, and can also be applied to easily damaged fruits such as peaches, cherries, plums, nectarines, apricots, cherries, American cherries, loquats, pears, prunes, and mangoes.

[0109] For example, in the above embodiment, a drop test method in which fruit is repeatedly dropped has been described, but the present invention is not limited to this, and if the impact resistance of the fruit can be evaluated by a single drop, it is possible not to drop the fruit repeatedly. Also, if a fruit with high impact resistance is to be tested, it is possible to increase the number of drops until damage occurs to the fruit skin, for example, 4 times, 5 times, 6 times, etc.

[0110] For example, in the above embodiment, a drop test device was described in which the drop height was set to 50 mm, but this is not limited to this and the drop height can be set to any desired value depending on the drop damage resistance of the target fruit.

[0111] For example, in the above embodiment, a drop test device that performs the opening and closing operation of the blades is described using a blade opening and closing device configured to fix and open a piston biased by a coil spring with a rotatable hook, but the present invention is not limited to this. For example, a blade opening and closing mechanism can be adopted in which one end of a rubber band is fixed to each of the inner ends 42, 42 of the blades 4a, 4b, and the other end of the rubber band is tied to a handle provided at one location on the inside of the side wall 21 of the frame 2, and the blades 4a, 4b are fixed in parallel by pulling the rubber band (when closed), and when opening, the handle is released to release the other end of the rubber band, thereby opening the blades 4a, 4b.

[0112] For example, in the above embodiment, a drop test apparatus having six compartments for accommodating individual fruits is illustrated, but the present invention is not limited to this, and the number of compartments can be more or less depending on the size of the fruit and the number of samples to be tested simultaneously. [Explanation of symbols]

[0113] 1: Drop test equipment 2: Frame 21,22 :Side wall 3: Case 32,321: Hard board 33,331:Disc 36,361: Band 4a, 4b: Spring part 42: Inner end F: Fruit

Claims

1. A drop test method for fruit, which checks the damage caused to the fruit by the impact when the fruit is dropped in order to verify the impact resistance of the fruit, comprising: A fruit drop test method comprising: sandwiching a hard disk between each of the fruits and the upper surface of a hard plate on which the fruit is placed; and dropping the hard plate while the fruit remains in contact with the disk.

2. 2. The method for drop testing of fruit according to claim 1, further comprising the step of wrapping and fixing the fruit and the disk with a strip, thereby maintaining the fruit in contact with the disk when the hard plate is dropped.

3. 2. The method for drop testing of fruit according to claim 1, wherein when the hard plate is dropped, the disk is sandwiched between the fruit and the upper surface of the hard plate, and a strip is wrapped around and fixed to the fruit and the hard plate, thereby maintaining the fruit in contact with the disk.

4. The method for fruit drop test according to claim 1 or 2, wherein the disc has a diameter of 5 to 15 mm and a thickness of 0.5 to 3 mm.

5. A fruit drop test device for use in the method according to any one of claims 1 to 4, comprising: A frame consisting of front, rear, left and right side walls; a case for containing fruit, the case being disposed within the frame; a pair of blades provided on the inside of both left and right ends of the frame, the pair of blades dropping the case by opening and closing the pair of blades; The case has a hard plate on the bottom surface for placing the fruit, and a disk made of hard material is arranged on the upper surface of the hard plate, The pair of blade portions are rectangular plates, each of which is supported on the front and rear side walls with its long side extending in the axial direction, and are fixed horizontally when closed, supporting the case from below at their inner ends, while when open, the fixed portions are released so that the case falls under its own weight. This is a fruit drop test device.

6. The disk has a convex portion on a surface that contacts the hard plate, a recessed portion is provided on an upper surface of the hard plate for engaging with a protruding portion of the disk to prevent the disk from shifting in a horizontal direction; 6. The fruit drop test device according to claim 5, wherein the hard plate is provided with a band for fixing the fruit with the disk sandwiched between the fruit and an upper surface of the hard plate.

7. The fruit drop test apparatus according to claim 5 or 6, wherein the disc has a diameter of 5-15 mm and a thickness of 0.5-3 mm.

Images