Reasonable design and transportation safety test for toy packaging cushions II

2.2 Understand the structural characteristics of toys to identify vulnerable parts

Toys are different from general electronic and mechanical products. Due to cost considerations, the material strength of the toy itself and the processing precision of the parts are not very high; the variety of toys is varied, the shapes are various, the shape structure is more complicated, and often there are some irregular components. This makes it easier for parts to loosen, localized cracks, etc. during transportation and handling. Therefore, in the toy packaging design, we must make a detailed understanding of the main function and structural characteristics of the toy, identify the most vulnerable parts, determine the maximum impact acceleration the toy can withstand, that is, the fragility of the toy itself. The test of brittleness of toys can refer to the test method for brittleness of electronic products. Using impact tester or free drop tester, the damage boundary curve of toys can be measured to determine the size of brittleness.

2.3 Select packaging material design packaging structure

According to the toy's circulation environment parameters and fragility, to choose the toy packaging materials, design a reasonable packaging structure. The outer packaging box of the toy can be a single layer of cardboard or corrugated cardboard. For a general electric toy, if the shape of the outer shell is relatively regular, a cardboard having a certain strength can be used as a packaging. However, considering the sales characteristics of the toy itself, the customer wants to see the specific product inside when purchasing the toy, so the outer box of the general toy has a larger visible window, which reduces the strength of the packaging box. For such toys, as long as a proper cushion is added to the box, the box can play a certain role. The thickness of the cushion can be based on experience or a simple drop experiment to protect the toy from damage. For high-end electronic toys, the size, shape and placement of internal liners need to be calculated, designed, and tested. The material is usually made of foamed plastic mats. The thickness of the liner can be calculated based on the following formula:

T=CH/G

Where: T is the thickness of the required liner; H is the drop height, depending on the loading and unloading environment, and the weight of the packaged object; G is the fragility of the packaged material, which is the multiple of the gravitational acceleration; c is the cushion material The minimum cushioning factor is related to the nature of the material itself.

Generally speaking, toys falling during loading and unloading are most likely to cause damage to the toy. Therefore, the thickness calculated according to the above formula is the cushion that the toy undergoes a drop impact without damage during transportation. Minimum thickness [2].

Considering that the toys in actual circulation are packed in corrugated boxes, the carton also has a certain protective effect on the toys. The calculated thickness of the liner can be multiplied by a coefficient K that is smaller than 1, and the thickness can be properly adjusted. Adjustments. The size of a specific K value requires a series of drop tests on corrugated boxes to obtain relevant empirical data.

The shape and the applied part of the pad are designed depending on the shape and structure of the toy, and upper and lower structures and left and right structures can be used. For example, toy vehicles should use left and right pad structures, and toy robots often use upper and lower pad structures. The contact area between the gasket and the toy should be selected as far as possible on the surface of the relatively flat housing to avoid weak links, such as the position of some small parts, and the position of the parts that are connected to the interior. When designing the shape of the gasket, these positions should be suspended to avoid direct exposure. The impact of external forces.

Green packaging is now advocated. Some countries have banned the use of foam plastics as packaging materials, toy packaging and inner boxes, and require the printing of "recycling marks" for consumers to handle. From an environmental point of view, foamed plastic liners, pulp molds or other degradable materials can be used instead of foamed plastic liners. According to relevant information, a company recently developed a new type of biodegradable packaging buffer material (ECO-Foam) with a starch content of >40%, a biodegradable ingredient of 60%, a foaming magnification of 30 times, and a density of 0.033g. /cm3, can be used as a buffer for precision instrumentation and high-end electronic products. A British company produces a paper roll called "FLEX-TRA", made from recycled fibers that can be recycled and reused; it can be biodegraded when discarded and will not cause environmental pollution. This paper roll has a lot of small cracks, and it opens up to form a honeycomb, which can act as a cushioning pad. Corrugated cardboard has good cushioning properties and can be folded into any shape according to the shape of the toy. The disadvantage of corrugated cardboard is that the core paper is prone to permanent deformation under heavy pressure and loses its protective effect on the contents. However, considering that toys are lighter than general electronic products, they will not exert too much pressure on cardboard. As for how to use several layers of corrugated, how to design the cushion structure, it is necessary to test the corrugated board of various types for corresponding cushioning performance, and obtain the same protection effect compared with the foamed plastic.

2.4 Simulating Transport Environment Testing Package Protection Effect

After the packaging design is completed, simulation tests should be conducted based on the transport loops that the toy may undergo. The main tests are: vibration, drop impact, horizontal impact and so on. The vibration test simulates the effect of vibrations on the toy due to the vibration of trains, cars, ships, etc. during transportation. The method is to place the packaged toy on a mechanical vibration table, vibrate at a certain frequency for 20 minutes, or perform sweep frequency vibration in the range of 0-50Hz to find the resonance point and check whether the toy has parts falling off, cracks, and components. Damage and so on. The drop impact and horizontal impact test are mainly to simulate the protection of the packaging on the interior toys under the impact of falling in loading and unloading and the start, stop, emergency brake and other impact conditions of the vehicle. Once the damage occurs, design parameters need to be adjusted and the packaging redesigned.

3 Conclusion

The packaging and transportation safety of high-end electronic toys has not attracted enough attention from the industry. With the increase in the value of the toys themselves, the packaging of the toys will become more scientific and reasonable.

(Text/New Gui Fang Cang Shijian Wang Jinchang Tianjin University of Science and Technology)

Packaging Engineering