The present invention relates to a sealing structure for a plastic packing box, allowing cover plates adapted to seal the mouth of the box simply and conveniently after the filling of it with articles.
Conventionally, the four bendable cover plates of a cardboard packing box or new moisture-proof plastic packing box configured respectively on the four sides of the mouth and bottom thereof are bended inward to form inner and outer layers to cover the box after it is filled with articles, achieving the complete covering of the top and bottom of the box. Thereafter, an adhesive tape is applied to the edges of the two bended outer cover plates opposite to each other to seal the box completely. However, such kind of adhesive tape sticking to seal a box may have no problem for cardboard boxes, but it is not ideal to use an adhesive tape to seal the mouth of a plastic box after it is filled with articles because the surface thereof is slippery and uneasy to be stuck, and the plate itself is hard and easy to be deformed. If a perfect sealing is needed, a highly sticky tape, hot sol or even nails must be used to seal the engagement rims of the bended cover plates after the box is filled with articles. If the sealing is still uneven, strapping is even used to carry out full box packing to achieve safe sealing, which not only increases sealing working hour and material cost but relies on relatively skilled personnel, resulting in the overall cost of package to be increased, being environmentally unfriendly, causing follow-up box opening and plate recycling classification process to be inconvenient.
The main object of the present invention is to provide a sealing structure for a plastic packing box, engaging mating having male and female buckling element with the sides of opposite plastic cover plates to form particular staking, buckling and sealing sides, and buckling the opposite cover plates together simply through the male, female buckling elements, thereby covering the top face of a box body neatly, and achieving both buckling and box sealing at the same time.
A sealing structure for a plastic packing box according to the present invention mainly provides a sealing structure configured on the mouth of the box adapted to seal the box after the packing of the plastic box. Referring to
Slightly concave mating faces 111, 121 are respectively configured on the engagement edges of the cover plates 11, 12 for the engagement of premade inverted U-shaped mating frames 20, 30 having a shape and size similarly to the ones of the sealing sides of the cover plate 11, 12, where the mating frames 20, 30 respectively have a groove 21 indented a proper depth similarly to the width of the mating face 111, 121, allowing the frames to be engaged with the edges of the cover plates 11,12, thereby forming a fixing frame edge for each cover plate. furthermore, the mating frames 20, 30 are respectively inserted with the edges of the cover plates 11, 12 to form sealing frame edges for engagement and stacking, thereby allowing the cover plates to be covered together to seal the box. Furthermore, the frame edge of the mating frame 30 engaged with one side of the cover plate 12 is indented slightly to form a stepped face for a stacking face to be flat after the cover plate 11 is covered on the frame edge of the mating frame 30. To ensure the engagements of the mating frames 20, 30 with the cover plates 11. 12 are stable, they can be bonded together simply by means of hot welding after the engagement because they are all made from plastics, resulting in the tight combination of the mating frame 20, 30 with the cover plates 11, 12 without doubt of falling off. Furthermore, the top surface 22 of the male mating frame 20 is extended outward like a cantilever, and the extension section close to the middle of the cover plate 11 is configured with a poking tab 23 having a proper width, allowing a unpacking force to be exerted stably; the poking table is extended unto a proper distance from the edge of the mating frame 30 at another side of the sealing line after the covering. In addition, a long striped-typed male buckling element 24 is configured on the middle of the inner side of an extended top plate face, and a plurality of male buckling elements 24 may also be configured separately according to the length of the plate face, thereby labor-saving and squeeze elastic auxiliary upon buckling. Furthermore, the female mating frame 30 at another side of the sealing line is extended with a length in a way of matching the top plate face 22 of the male mating frame 20, and a concave stepped plate face 31 is configured on the frame body top face for the accommodation of the extended top plate face 22, with a female buckling element 32 corresponding to the male buckling element 24 being configured on the stepped plate face 31, capable of engagement thereof with the male buckling element 24. In addition, concave and convex portions for auxiliary positioning may respectively configured on the sides of the buckling elements, but the configurations are not necessary such that they are not shown in the figures; they are convenient for the engagement and positioning of the two mating frames 20, 30. Furthermore, a bendable buckling sheet 25 flush with one side of the box body and extended from the two ends of the mating frame 20 can be bended directly to engaged with a corresponding groove buckling element 14 respectively configured on two opposite side plates 13 of the box body, thereby to buckle the two side ends tightly and ensure the top face of the box can be sealed neatly and the sealing can be safe and stable.
For forming convenience and practical buckling operation requirements, the shapes of male buckling element 24 and female buckling element 32 may be set to the ones of buckling elements shown in