The design of carton size
Size design is a very important link in carton design, if the carton size deviation, it even the most basic convenient storage and transportation function can not be realized. Therefore, the size of the carton design must be scientific and reasonable.
The size of the carton includes inner size, outer size and manufacturing size, as shown in Figure 3.
1. Inner size
Under normal circumstances, the first carton size design. The inner size of the carton is determined by the physical measurement size of the inner contents or the outer size calculated by the combination of the physical contents. The arrangement of the contents should be as space-saving as possible, and the factors of support should be considered reasonably. The determining factors of the carton inner size mainly include the maximum outer size of the inner contents, the tolerance coefficient of the inner contents, the arrangement and number of the inner contents, and the relevant size of the liner and buffer parts of the inner contents.
2. External size
The outer size of the carton is generally calculated by the inner size and the thickness of the carton wall after the carton is formed. Outer dimension is calculated by carton volume and The important design basis of external packaging or transportation storage tools (such as trucks and freight cars, containers, pallets, etc.). In order to facilitate the loading of cartons into containers, the maximum outer size of the carton designed by the designer shall not be larger than the outer size provided by the user.
3. Manufacturing size
Manufacturing size refers to the processing and manufacturing size of the carton, which is the marked size on the expansion diagram of the structure drawing. The manufacturing size is measured by the press line on the unfolded box blank. The indentation roll on the slitter presses out a groove on the position of the press line, and the press line is the center line of the groove. The distance between the two lines is the manufacturing size. Manufacturing dimensions are often determined by calculation of internal dimensions.
4, the difference between the manufacturing size and the external size when the cardboard is folded into 90 degrees, the knife line press down, if you can fold over it is a normal carton, but in fact, the process of cardboard folding down is not done, generally speaking, cardboard or three layers or five layers, plus the thickness of the paper, the cardboard in the end is not realistic. When the wire cutter presses down, the cardboard will immediately pop up. Take the three-layer board as an example, that is to say, the thickness of the bottom is the thickness of three pieces of paper. The thickness is d, namely, the thickness of the face paper, the inner paper and the core paper.
Line depth a is equal to the board thickness st minus d, so it can be seen that the difference in line depth determines the difference in manufacturing size, and the difference in the thickness of each layer of paper also determines the difference in retracting size. If the paper manufacturers use is particularly good and thick, then the size will be different.
5. Partition size design
For the design principle of the grid, please refer to the elliptical container in the upper right corner of Figure 9, with length of 126.5mm, width of 107mm and height of 182mm. How do we design this object? First of all, put the object into the carton and draw the thickness of the cardboard, such as 5mm marked by the red circle in the figure. Then, plus the cardboard on both sides of the object, the length, width and size are added to see how many such objects to put. After the plane layout is finished, the length and width are reduced by 4mm, one side needs to leave a 2mm gap, otherwise the material is not plugged in after the grid is done, in the total length and total width of the gap minus 2mm, this is the design of the internal grid file.
