A double-layer container

Abstract

The present invention provides a double-layer container, belonging to the technical field of daily necessities. It solves the problem of how to make the double-layer container have both high overall strength and rapid recycling. The double-layer container comprises an inner container with a bottom made of plastic and an outer layer body made of paper in a cylindrical shape, the outer layer body is sleeved outside the inner container, a locking structure is provided between the outer layer body and the inner container to clamp the outer layer body on the outer peripheral surface of the inner container, and a tearing piece that can tear and destroy the outer layer body is provided on the outer layer body. The double-layer container strengthens the inner container and the outer layer body in the radial direction respectively through an annular groove and an annular protrusion, has high overall strength, and rapid recycling is achieved through the tearing piece provided on the outer layer body.

Description

Technical Field

[0001] The invention belongs to the technical field of daily necessities and relates to a container, in particular a double-layer container. Background Art

[0002] Disposable containers are items that are used once and need to be thrown away, such as paper cups, paper bowls, plastic cups, plastic bowls, etc. For example, paper cups are made of cardboard through winding and bonding processes to form a single-layer cup body. Since the cup body made of pure cardboard is easily softened when exposed to water and leaks, the water or beverage in the cup cannot be kept for a long time, and the softened cup body is not easy to pick up. Therefore, disposable paper cups usually have a thin layer of waterproof PE film sprayed on the side of the paper cup that contacts water, and a layer of edible wax is coated on the PE film.

[0003] In order to solve the problem of scalding prevention, a double-layer container is designed, that is, the above-mentioned single-layer paper cup is used as the inner cup, and an outer cup is added outside the inner cup, and there is an anti-scalding gap between the outer cup and the inner cup, so that when the hand holds the outer cup, it will not directly touch the inner cup to achieve the purpose of scalding prevention. This double-layer structure of paper cups has also been widely used, and because they are all made of paper materials, they are very convenient to recycle.

[0004] In recent years, the market has further requirements for the durability of double-layer containers, so there are plastic inner cups made of degradable plastics, and a paper outer cup with a gap between the plastic inner cup and the plastic inner cup is sleeved outside the plastic inner cup to form a double-layer container composed of plastic and paperboard. For example, the disposable paper-plastic insulation cup (patent number 200920148189.3) and the heat insulation structure of paper cup (201010566808.8) disclosed in Chinese patents. In addition, the bottom of the outer cup of the double-layer container of this structure is folded into a two-layer structure for reinforcement, resulting in that the lower part of the outer cup cannot form an effective reinforcement structure, so it needs to be reinforced by glue bonding. If glue bonding is not used, it is easy to deform in the radial direction of the cup body. When picking up the outer cup, the outer cup will contact the inner cup after being compressed and deformed. Moreover, the inner cup has no reinforcement structure, and the inner cup is also easy to deform when heated, resulting in low overall strength, and it is easy to burn hands when filling hot water and taking it.

[0005] This double-layer container formed by plastic and paper has a big drawback that it is not very friendly to the environment. Although it is a degradable plastic, it takes 2-3 years for the degradable plastic to degrade, and the use of disposable cups is also huge. Discarding them at will will also cause a great burden on the environment. Therefore, it is very necessary to recycle this double-layer container. However, in consideration of scalding prevention and ease of use, the connection between the outer cup and the inner cup of this double-layer container is very firm, and the connection between the plastic inner cup and the paper outer cup needs to be fixed with glue, which will cause great difficulties in recycling: first, since this paper cup is made of different materials, the inner cup and the outer cup must be separated when recycling, but the outer cup and the inner cup are firmly bonded by glue, and the outer cup has no place to bear force, so it is not easy to separate the outer cup from the inner cup; second, the glue adhering to the plastic inner cup is an impurity, but the glue is difficult to remove on the plastic inner cup, and the purification of recycled plastic becomes very difficult.

[0006] In addition to directly gluing the plastic inner cup and the paper outer cup together, some people have disclosed that the inner cup and the outer cup are fixed by a snap-fit ​​structure, and the snap-fit ​​structure is applied to the plastic inner cup and the paper outer cup for connection. For example, a double-layer container disclosed in the United States patent (publication number is US2015 / 0048086A1) has a locking structure that uses the inner side wall of the outer cup to form a step, the bottom of the inner cup is placed on the step, and the edge of the outer cup mouth is inserted into the inner cup roll mouth. It can be seen that the structural strength of this snap-fit ​​structure is not high, especially the inner cup is easy to fall out of the outer cup, so glue bonding is also required to prevent the inner cup from being easily separated from the outer cup. In addition, the overall strength of this snap-fit ​​structure is not high. As mentioned above, only the structure folded into two layers at the bottom of the outer cup is radially reinforced, and the inner cup is not radially reinforced. Moreover, when the outer cup is snapped with the inner cup, it is only snapped in one direction in the up and down direction. The overall structural strength is not high, and it is easy to burn hands when filling hot water and taking it out.

[0007] Therefore, a double-layer container which has sufficient overall strength and is convenient for recycling is expected by the market. Summary of the invention

[0008] The present invention aims at the above problems existing in the prior art and proposes a double-layer container. The technical problem to be solved by the present invention is how to make the double-layer container have both high overall strength and rapid recycling.

[0009] The present invention is achieved through the following technical solutions: a double-layer container, comprising an inner container with a bottom made of plastic and an outer layer body made of paper in a cylindrical shape, the outer layer body being sleeved on the outside of the inner container, characterized in that a locking structure is provided between the outer layer body and the inner container to clamp the outer layer body on the outer circumferential surface of the inner container, the locking structure comprising an annular groove formed on the outer circumferential surface of the inner container and recessed in the radial direction of the inner container and an annular protrusion formed on the inner circumferential surface of the outer layer body in a winding manner, or the locking structure comprises an annular protrusion formed on the outer circumferential surface of the inner container and an annular groove formed on the circumferential surface of the outer layer body in a winding manner and recessed in the radial direction of the outer layer body, the annular protrusion is embedded in the annular groove, and a tear sheet that can tear and destroy the outer layer body is provided on the outer layer body.

[0010] The double-layer container uses a glue-free locking structure to lock the outer layer on the inner container, so that the outer layer is firmly connected to the inner container and is not easy to separate. When the double-layer container is recycled after use, the outer layer can be easily destroyed and torn off by the tearing piece set on the outer layer, so that the outer layer can be easily separated from the inner container, and then a plastic inner container without glue impurities is obtained, which realizes rapid recycling. In addition, an annular protrusion is formed on the outer layer, so that the outer layer forms a reinforcement similar to an arch bridge in the radial direction. In particular, after the ring is formed, the radial reinforcement reaches the maximum, so that the cup is not easy to deform. On this basis, the inner container forms an annular groove on the side wall, which also strengthens the inner container in the radial direction. After the annular protrusion is embedded in the annular groove, the annular protrusion supports the annular groove of the inner container in the radial direction, so that the overall strength in the radial direction after the connection is further improved. Therefore, this structure can enhance the overall strength of the outer layer connected to the inner container. At the same time, the winding thickness of the annular protrusion or the winding depth of the annular groove can be controlled during production, so that the insulation distance between the inner container and the outer layer can be adjusted.

[0011] In the above double-layer container, the width of the annular protrusion is greater than the depth of the annular groove, so that there is a gap between the outer wall of the inner container and the inner wall of the outer layer. This structure enables the outer layer at the locking structure to also prevent scalding, because the outer peripheral part of the cup close to the bottom is also the part that is often held, and the enlarged width design can enhance the anti-deformation ability of the annular curling edge, increase the structural strength, and also increase the area of ​​heat clamping.

[0012] In the above double-layer container, the cross-sectional shape of the annular groove is arc, square or circular, and the cross-sectional shape of the annular protrusion is circular or elliptical, which is convenient for good clamping during thermal expansion.

[0013] In the above-mentioned double-layer container, the cup mouth of the inner container has an annular rib that is turned out toward the outer wall of the inner container, the outer layer body has no bottom, and the annular rib and the bottom of the inner container are both located outside the outer layer body, the tear sheet is located at the edge of the cup mouth of the outer layer body and extends out of the cup mouth, and the tear sheet is bent toward the outer wall of the outer layer body. The cup mouth of the outer layer body can be positioned with the upper part of the inner container by a tight fit, because the inner diameter of the cup mouth of the outer layer body is fixed, and the cup body of the inner container is conical, and the closer to the cup mouth of the inner container, the greater the strength of the tight fit. This fixing method can make the outer layer body positionable at both the upper and lower parts.

[0014] On the basis of realizing rapid recycling, the tearing piece can also be fully utilized so that the tearing piece can tear and destroy the outer layer body and can also enhance the glue-free fixed connection between the outer layer body and the inner container, thereby increasing the strength of the double-layer container. That is, the bottom of the outer layer body is locked to the inner container through a locking structure. On the basis of the lower limit of the outer layer body, the tearing piece is arranged at the cup mouth of the outer layer body and the tearing piece is bent toward the outer wall of the outer layer body and the portion of the tearing piece close to the cup mouth is against the annular rib of the inner container. According to the different structures of the annular rib, such as a flat rib or an L-shaped rib, the tearing piece can be bent and deformed outward to generate elastic force and act on the outer layer body, so that the locking structure of the bottom of the outer layer body connected by the groove has a pre-tightening force to avoid movement, because the thin plastic inner container and the paper outer layer body will have a large thermal expansion and contraction, which will cause the locking structure to loosen, and the tearing piece generates these pre-tightening forces to eliminate these effects, so that the entire outer layer body can be firmly connected to the inner container without glue, thereby increasing the use strength.

[0015] In the above double-layer container, the tearing piece is connected to the cup mouth of the outer layer as the starting part, and a tearing line is set on the cup body of the outer layer from the starting part, and the tearing line is formed by indentations that make the cup body thinner. The tearing line can extend in any direction on the cup body, and the outer layer is more easily destroyed by the cooperation of the tearing line and the tearing piece.

[0016] In the above double-layer container, the annular rib is formed by winding the cup mouth of the outer layer outward, and the tear sheet is bent outward and closely attached to the outer side wall of the outer layer. This structure makes it easy to tear off the tear sheet.

[0017] In the above-mentioned double-layer container, the tear line has an indentation at one end at the starting portion, and the indentation extends to the cup opening of the outer layer. Since the tear sheet is pressed tightly in the annular rib, the inertial force generated during tearing and the indentation can make it easier to tear the outer layer off along the tear line. For the best effect, the tear line can be set along the inertial force direction, such as vertically downward.

[0018] In the above-mentioned double-layer container, the annular rib is formed by folding the cup mouth of the outer layer outward into a plane, or the annular rib is formed by folding the cup mouth of the outer layer outward twice into an L shape, the tearing piece and the cup mouth of the outer layer are an integrated structure, and the arc portion formed when the tearing piece is bent outward abuts against the annular rib. The integrated structure means that the tearing piece connected to the cup mouth is directly cut out during cutting, such a tearing piece can maintain good elastic deformation when bent outward, and the arc portion has the best elastic force when abutting.

[0019] In the above double-layer container, the tear line at the starting point is an indentation, which is a distance away from the outer cup mouth. The tear line arrangement of this structure improves the strength of the cup mouth and enables the tear sheet to have the best elastic effect.

[0020] This double-layer container can be further improved by making the outer layer directly from plastic, and making the plastic into a plastic plate with the same thickness as A4 paper, and then using this plastic plate as an outer paper cup, and using the same method as above to make a double-layer cup, so that it can be recycled when it is recycled, without the need to separate paper from plastic. This case can also be:

[0021] A double-layer container, comprising an inner container with a bottom made of plastic and an outer layer body made of plastic, wherein the outer layer body is sleeved on the outside of the inner container, and is characterized in that a locking structure is provided between the outer layer body and the inner container to clamp the outer layer body on the outer circumferential surface of the inner container, the locking structure comprises an annular groove formed on the outer circumferential surface of the inner container and recessed in the radial direction of the inner container, and an annular protrusion formed on the inner circumferential surface of the outer layer body in a winding manner, or the locking structure comprises an annular protrusion formed on the outer circumferential surface of the inner container and an annular groove formed on the circumferential surface of the outer layer body and recessed in the radial direction of the outer layer body in a winding manner, and the annular protrusion is embedded in the annular groove.

[0022] Compared with the prior art, this double-layer container has the following advantages:

[0023] 1. The overall strength is high. The inner container and the outer layer are strengthened in radial direction by the annular groove and the annular protrusion respectively. When the annular protrusion is embedded in the annular groove, the annular protrusion supports the annular groove, which further strengthens the overall strength.

[0024] 2. When hot drinks are contained, the outer layer can be further locked on the inner container by the locking structure, while when cold drinks are contained or not in use, the tear sheet strengthens the connection.

[0025] 3. It can be recycled quickly and conveniently. The tear sheet provided on the outer layer can easily destroy and tear off the outer layer, so that the outer layer can be easily separated from the inner container, thereby obtaining a plastic inner container without glue impurities.

[0026] 4. The annular groove is formed on the inner container made of plastic material, and the outer part of the paper material forms a paper annular protrusion. When the double-layer container is used to hold high-temperature beverages, the thermal expansion coefficients of plastic and paper are different. The thermal expansion of paper is almost unnecessary, while the thin plastic annular groove will produce a small amount of thermal expansion. On the basis of the annular protrusion being embedded in the annular groove, the slight thermal expansion of the upper and lower groove walls of the annular groove will further clamp and lock the annular protrusion, thereby enhancing the connection strength and reliability of the double-layer container. Another locking structure, that is, a thin annular protrusion formed on the plastic inner container will also produce a small amount of thermal expansion. On the basis of the annular protrusion being embedded in the annular groove, the annular protrusion is tightened and locked on the upper and lower groove walls of the annular groove with very small thermal expansion. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1-4 Schematic diagram of different tearing structures of the double-layer container.

[0028] Figure 5 It is a schematic diagram of the vertical cross-sectional structure of the double-layer container.

[0029] Figure 6 yes Figure 5 An enlarged view of part A and a schematic diagram of the enlarged structure after thermal expansion.

[0030] Figure 7 It is a schematic diagram of the locking situation in which the annular protrusion is larger than the annular groove and the enlarged structure after thermal expansion.

[0031] Figure 8 and Fig. 9 It is a position relationship diagram between the tear line and the tear piece.

[0032] Fig.10 and 11 It is a schematic diagram of the structure of different annular ribs in the fourth embodiment.

[0033] Fig.12 It is a schematic diagram of the vertical cross-sectional structure of the double-layer container of the second embodiment.

[0034] Fig.13 It is a schematic diagram of the vertical cross-sectional structure of the double-layer container of the third embodiment.

[0035] Fig.14 and Fig.15 It is a structural schematic diagram of the double-layer cup of the fifth embodiment.

[0036] In the figure, 1, inner container; 11, annular rib; 12, upper and lower groove walls; 2, outer layer; 4, tear sheet; 5, tear line; 6, annular groove; 7, annular protrusion; 8, gap. DETAILED DESCRIPTION

[0037] The following are specific embodiments of the present invention, and the technical solutions of the present invention are further described in conjunction with the accompanying drawings, but the present invention is not limited to these embodiments.

[0038] Embodiment 1:

[0039] like Figure 1 As shown, the double-layer container is a cup-shaped container in the shape of a truncated cone, comprising an inner container 1 with a bottom made of plastic and an outer layer body 2 made of paper, the outer layer body 2 is sleeved on the outside of the inner container 1, the cup mouth of the inner container 1 has an annular rib 11 turned out toward the outer wall of the inner container 1, the outer layer body 2 has no bottom and the annular rib 11 and the bottom of the inner container 1 are both located outside the outer layer body 2, a locking structure is provided between the outer layer body 2 and the inner container 1 for clamping the outer layer body 2 on the outer peripheral surface of the inner container 1, a tearing piece 4 for tearing and destroying the outer layer body 2 is provided on the outer layer body 2, and a tearing line 5 is provided on the cup body below the tearing piece 4 for convenient destruction of the outer layer body 2. The outer layer 2 can be locked on the inner container 1 by adopting a locking structure without glue, so that the outer layer 2 is firmly connected to the inner container 1 and is not easy to separate. When the double-layer container is recycled after use, the outer layer 2 can be easily destroyed and torn off by using the tear sheet 4 arranged on the outer layer 2, so that the outer layer 2 can be easily separated from the inner container 1, thereby obtaining a plastic inner container 1 without glue impurities, thereby realizing rapid recycling.

[0040] The tear sheet 4 can have various structures, such as Figure 2 As shown, two sets of tearing pieces 4 and tearing lines 5 are provided on the outer layer 2 of the double-layer container to facilitate the destruction of the outer layer 2. Figure 3 As shown, the tear sheet 4 is arranged on the outer layer 2 itself and the tear line 5 is arranged transversely in an annular manner, and as shown in FIG. Figure 4 As shown, a part of the cup body is used as the tearing piece 4, that is, the part formed by the tearing line 5 of a right angle on the cup body which is easy to be pressed in and pinched by fingers is used as the tearing piece 4.

[0041] like Figure 5As shown, the locking structure is located at the lower part or the middle and lower part of the double-layer container, including an annular groove 6 and an annular protrusion 7. The annular groove 6 is recessed along the radial direction of the inner container 1 so as to be formed on the outer peripheral surface of the inner container 1. It has upper and lower groove walls 12, which are directly formed when the inner container 1 is pressed and formed. Its cross-section is in the shape of an arc. The annular protrusion 7 is formed on the inner peripheral surface of the outer layer body 2. It is wound from the bottom of the outer layer body 2 to the inner peripheral surface. According to different processes, it can be wound into a circular or elliptical shape. The annular protrusion 7 is embedded in the annular groove 6 and the width of the annular protrusion 7 is greater than the depth of the annular groove 6, so that there is a gap 8 between the outer wall of the inner container 1 and the inner wall of the outer layer body 2. In order to ensure that there is enough gap 8 at the locking structure, the part close to the bottom of the inner container 1 shrinks inward to increase the gap 8. The annular protrusion 7 formed by winding can be adjusted. When the gap 8 needs to be enlarged, the outer diameter of the annular protrusion 7 can be increased, which makes it easier to adjust the gap in actual production for different use environments.

[0042] like Figure 6 As shown, during the initial sleeve assembly of the locking structure, due to the error in the matching dimensions, the annular protrusion 7 cannot be completely engaged in the annular groove 6. Figure 6 On the left side, the groove width of the annular groove 6 is larger than the width of the annular protrusion 7. In this way, the fit between the annular protrusion 7 and the annular groove 6 is a clearance fit. This clearance fit will cause the shell to move. However, when high-temperature beverages are contained inside, the thermal expansion coefficients of plastic and paper are different. The thermal expansion of paper is almost unnecessary, while the thin plastic annular groove 6 will produce a small amount of thermal expansion. In addition, the full cup of hot beverage will cause the plastic thin wall to deform and form a Figure 6 The best state on the right side is that the groove is completely wrapped and clamped on the annular protrusion 7. After many sampling tests and observations, the upper and lower walls can be clamped and locked to reduce the movement. There are many reasons why it cannot be completely wrapped, which may be affected by the temperature, plastic material and other aspects.

[0043] like Figure 7 As shown, Figure 7 On the left side, the width of the annular protrusion 7 is greater than the groove width of the annular groove 6. In this way, the annular protrusion 7 is only partially embedded in the annular groove 6. This structure is not very stable, and the inner container 1 is easy to fall out of the outer layer 2. When a high-temperature beverage is contained inside, the thermal expansion coefficients of plastic and paper are different. The thermal expansion of paper is almost unnecessary, while the annular groove 6 made of thin plastic material will produce a small amount of thermal expansion, causing the plastic thin wall to deform and form a Figure 7 In the optimal state on the right side, the annular protrusion 7 is completely embedded in the annular groove 6. After multiple sampling tests and observations, it is determined that more contact surfaces of the upper and lower walls can contact with the annular protrusion 7 and form a clamp, reducing the situation where the outer layer 2 is separated from the inner container 1.

[0044] When the container is not used or used to hold cold drinks, the tear sheet 4 can be fully utilized so that the tear sheet 4 can tear and damage the outer layer 2 and strengthen the glue-free fixed connection between the outer layer 2 and the inner container 1, thereby increasing the strength of the double-layer container. Figure 5 As shown, the tearing piece 4 is located at the edge of the cup mouth of the outer layer 2 and extends out of the cup mouth, the annular rib 11 is formed by winding the cup mouth of the outer layer 2 outward, and the tearing piece 4 is bent outward and closely attached to the outer side wall of the outer layer 2, so that the portion of the tearing piece 4 close to the cup mouth abuts against the annular rib 11 of the inner container 1. This structure creates a tight fit between the cup mouth of the outer layer 2 and the annular rib 11, so that the outer layer 2 is fixed at both the upper and lower parts.

[0045] like Figure 1 As shown, the tearing piece 4 is connected to the cup mouth of the outer layer 2 as the starting part, and a tearing line 5 is set on the cup body of the outer layer 2 from the starting part. The tearing line 5 is formed by the indentations that make the thickness of the cup body thinner. The tearing line 5 and the tearing piece 4 cooperate to make the outer layer 2 easier to destroy. Figure 8 In the unfolded view of the outer layer 2, one end of the tear line 5 at the starting part is an indentation, and the indentation extends to the cup mouth of the outer layer 2, and the other end of the tear line 5 is vertically downward. In this way, when the tear sheet 4 is pulled out, the outer layer 2 can be easily torn off along the tear line 5 by the inertial force combined with this indentation.

[0046] Embodiment 2:

[0047] The second embodiment is basically the same as the first embodiment, except that the locking structure is as follows. Fig.12 As shown, it includes an annular protrusion 7 formed on the outer circumference of the inner container 1 and an annular groove 6 with upper and lower groove walls 12 formed on the inner circumference of the outer layer 2, and the annular protrusion 7 is embedded in the annular groove 6. The annular protrusion 7 on the inner container 1 is formed by protruding from the inside to the outside, and the annular groove 6 is formed by bending the bottom of the outer layer 2. Figure 8 As shown, the specific process is to first fold the fan-shaped paperboard of the outer layer 2 along the folding line 13 at the bottom of the outer layer 2 and fit it with the inner wall of the outer layer 2, and then fold two outwardly protruding groove walls 12 radially on the folded part along the folding line 14, and then bond the fan-shaped paperboard to form a conical outer layer. The annular protrusion 7 formed on the plastic inner container 1 strengthens the inner container 1 in the radial direction. The annular groove 6 formed on the outer layer 2 is formed by two protruding upper and lower groove walls 12, the radial strength of the outer layer 2 is improved, and the inner container 1 will also produce a small amount of thermal expansion. On the basis of the annular protrusion 7 being embedded in the annular groove 6, the annular protrusion 7 is tightened and locked on the upper and lower groove walls 12 of the annular groove 6 with very small thermal expansion, so that the overall strength of the outer layer 2 and the inner container 1 in the radial direction is strengthened.

[0048] Embodiment 3

[0049] The third embodiment is basically the same as the second embodiment, except that the upper and lower groove walls 12 of the annular groove 6 are combined with Fig.13 and Fig. 9 As shown, the specific process is to first fold the fan-shaped paperboard of the outer layer 2 along the folding line 13 at the bottom of the outer layer 2 and fit it with the inner wall of the outer layer 2, and then fold an upper groove wall protruding outward radially along the folding line 14 on the folded part, and then bond the fan-shaped paperboard to form a conical outer layer, and roll the double-layer paperboard into the lower groove wall at the folding line 13, that is, the lower groove wall is formed by rolling the double-layer paperboard. This structure can further strengthen the radial structural strength of the outer layer.

[0050] Embodiment 4:

[0051] The fourth embodiment is basically the same as the first embodiment, except that the tear sheet 4 bends outward to generate elastic force and acts on the outer layer 2, so that the bottom of the outer layer 2 has a pre-tightening force through the locking structure of the annular groove 6 and does not move. Fig. 9 As shown, press Fig. 9 When the outer layer 2 is cut out in the unfolded state and then formed into the outer layer 2 by winding and bonding, the tear sheet 4 and the outer layer 2 are an integral structure, and such a tear sheet 4 can maintain good elastic deformation when bent outward. Fig.10 As shown, the annular rib 11 is formed by folding the cup mouth of the outer layer 2 outwardly into a flat shape, or as shown in Fig.11 As shown, the annular rib 11 is formed by folding the cup mouth of the outer layer 2 outward twice into an L shape, and the arc portion formed when the tear sheet 4 is bent outward abuts against the annular rib 11. The tear line 5 of this structure is located at the beginning of a section of indentation, and the indentation is a distance away from the cup mouth of the outer layer 2, so that the strength of the cup mouth is improved, so that the tear sheet 4 can have the best elastic effect.

[0052] Embodiment five:

[0053] like Fig.14A double-layer cup includes an inner container 1 with a bottom made of plastic and an outer layer body 2 made of plastic. The outer layer body 2 is sleeved on the outside of the inner container 1, and a locking structure is provided between the outer layer body 2 and the inner container 1 to clamp the outer layer body 2 on the outer peripheral surface of the inner container 1. The plastic used for the outer layer 2 is a thin plastic plate with a thickness of 0.5mm-2mm. This thin plastic plate is rolled and folded to form the outer layer 2. The locking structure is the same as the locking structure of Example 1. The locking structure is located in the lower part or the lower middle part of the double-layer container, and includes an annular groove 6 and an annular protrusion 7. The annular groove 6 is recessed along the radial direction of the inner container 1 and is formed on the outer peripheral surface of the inner container 1. It has upper and lower groove walls 12, which are directly formed when the inner container 1 is pressed and formed. The cross-sectional shape is arc-shaped. The annular protrusion 7 is formed on the inner peripheral surface of the outer layer 2. It is rolled from the bottom of the outer layer 2 to the inner peripheral surface. According to different processes, it can be rolled into a circular or elliptical shape. The annular protrusion 7 is embedded in the annular groove 6 and the width of the annular protrusion 7 is greater than the depth of the annular groove 6, so that there is a gap 8 between the outer wall of the inner container 1 and the inner wall of the outer layer 2. Or the locking structure is the same as Example 2, such as Fig.15 As shown, the locking structure includes an annular protrusion 7 formed on the outer circumference of the inner container 1 and an annular groove 6 having upper and lower groove walls 12 formed on the inner circumference of the outer layer 2, and the annular protrusion 7 is embedded in the annular groove 6. The annular protrusion 7 on the inner container 1 is formed by protruding from the inside to the outside, and the annular groove 6 is formed by bending the bottom of the outer layer 2.

[0054] The specific embodiments described herein are merely examples of the present invention. A person skilled in the art may make various modifications or additions to the specific embodiments described or replace them in a similar manner without departing from the scope of the present invention or exceeding the scope defined by the appended claims.

Claims

1. A double-layer container, comprising an inner container (1) made of plastic with a bottom and an outer layer (2) made of paper in a cylindrical shape, wherein the outer layer (2) is sleeved outside the inner container (1), characterized in that: A locking structure is provided between the outer layer body (2) and the inner container (1) for clamping the outer layer body (2) on the outer peripheral surface of the inner container (1), the locking structure comprising an annular groove (6) formed on the outer peripheral surface of the inner container (1) and recessed in the radial direction of the inner container, and an annular protrusion (7) formed on the inner peripheral surface of the outer layer body (2) in a winding manner, or the locking structure comprises an annular protrusion (7) formed on the outer peripheral surface of the inner container (1) and an annular groove (6) formed on the inner peripheral surface of the outer layer body (2) and recessed in the radial direction of the outer layer body in a winding manner, the annular protrusion (7) is embedded in the annular groove (6), and a tearing piece (4) capable of tearing and destroying the outer layer body (2) is provided on the outer layer body (2), the cup mouth of the inner container (1) has an annular rib (11) turned outward toward the outer wall of the inner container (1), the outer layer body (2) has no bottom, and the annular rib (11) and the bottom of the inner container (1) are both exposed from the outer layer body. (2), the tearing piece (4) is located at the edge of the cup mouth of the outer layer body (2) and extends out of the cup mouth, the tearing piece (4) is bent toward the outer wall of the outer layer body (2), the tearing piece (4) is connected to the cup mouth of the outer layer body (2) as the starting part, and a tearing line (5) is provided on the cup body of the outer layer body (2) and is opened from the starting part, the tearing line (5) is formed by indentations arranged at intervals to make the thickness of the cup body thinner, and the annular retaining edge (11) is formed by the cup of the outer layer body (2). The outer layer (2) is wound outwardly, the tear sheet (4) is bent outwardly and closely attached to the outer wall of the outer layer (2), the annular rib (11) is formed by folding the cup mouth of the outer layer (2) outwardly into a flat shape, or the annular rib (11) is formed by folding the cup mouth of the outer layer (2) outwardly twice into an L shape, the tear sheet (4) and the cup mouth of the outer layer (2) are an integrated structure, and the arc portion formed when the tear sheet (4) is bent outwardly abuts against the annular rib (11).

2. The double-layer container according to claim 1, characterized in that: The width of the annular protrusion (7) is greater than the depth of the annular groove (6), so that a gap (8) is provided between the outer wall of the inner container (1) and the inner wall of the outer layer body (2).

3. The double-layer container according to claim 1 or 2, characterized in that: The cross-sectional shape of the annular groove (6) is arc-shaped, square-shaped or circular, and the cross-sectional shape of the annular protrusion (7) is circular or elliptical.

4. The double-layer container according to claim 3, characterized in that: One end of the tear line (5) located at the starting portion is an indentation, and the indentation extends to the cup opening of the outer layer body (2).

5. The double-layer container according to claim 3, characterized in that: One end of the tear line (5) located at the starting portion is an indentation, and the indentation is a distance away from the cup mouth of the outer layer body (2).

Images