Apparatus and method for producing recyclable double-walled cups

Abstract

To disclose a press device that combines two cups to be stacked on top of each other so that a double-walled cup is formed after pressed, the two cups are respectively made of a first material and a second material.SOLUTION: A press device includes an upper mold 11 and a lower mold 12, where in the structure thereof the upper mold includes a first hollow cylindrical body and a second hollow cylindrical body movable inside the first hollow cylindrical body in a vertical direction, and the lower mold includes a third hollow cylindrical body that houses and holds the two cups and a pushrod disposed in the center of the third hollow cylindrical body to push up the two cups. The press device does not include arraying structures to position the two cups. The present disclosure also includes a method for combining the two cups by using the press device, and the combining method does not include a step of rotating or positioning the two cups.SELECTED DRAWING: Figure 1A

Description

[Technical field]

[0001] FIELD OF THE DISCLOSURE The present disclosure relates to an apparatus and method for making a double-walled cup. More specifically, the disclosed invention relates to an apparatus and method for making a recyclable double-walled cup by joining an outer cup with an inner cup characterized by an extending tab extending from the rim of the inner cup. [Background technology]

[0002] Disposable cups are widely used today, and as a result the task of recycling disposable cups has become an increasingly important challenge. Many techniques have been developed to address this issue. One of them involves using a double-layer cup made of different materials that can be easily separated for recycling after use.

[0003] US Patent No. 9,301,630 is directed to a disposable cup comprising an outer paper cup and an inner plastic cup having an extension sheet extending from its curled edge and integrally formed therewith. The extension sheet can be pulled out from the bottom of the cup to allow separation of the inner plastic cup and the outer paper cup, facilitating complete recycling of the disposable cup after use. However, this approach requires consideration of not only the ease of separation, but also the tightness and stability of the engagement between the inner cup and the outer cup during use.

[0004] To ensure that the inner and outer cups are tightly engaged, a press consisting of upper and lower molds is used during cup production to roll and press the rims of the inner plastic cup and the outer paper cup together. However, the extension sheet of the inner plastic cup interferes with the pressing process, causing delays in production. Cutting notches into the press can also help to provide precise alignment of the extension sheet, but this also requires an additional step of rotating the cup to fit into the notches, which inevitably slows down the production process.

[0005] In view of the above, there is a need in the related art for an improved pressing apparatus that is not affected by any protrusions on the rims of the cups and can smoothly join the inner and outer cups regardless of the position of the extension seats. Summary of the Invention

[0006] The following presents a simplified summary of the disclosure in order to provide the reader with a basic understanding. This summary is not an exhaustive overview of the disclosure, nor does it identify key / critical elements of the invention or delineate the scope of the invention. Its sole purpose is to present some concepts disclosed herein in a simplified form as a prelude to the more detailed description that is presented later.

[0007] As embodied and broadly described herein, it is an object of the present disclosure to provide a pressing apparatus and joining method that utilizes a pressing apparatus to engage two cups, one of the cups having an irregular rim, and in particular a tab extending from the rim, for the purposes of significantly increasing manufacturing efficiency.

[0008] In one aspect, the present disclosure is directed to a pressing device comprising an upper mold and a lower mold vertically aligned to join two cups made of a first and a second material, respectively, and stacked together to form a double-walled cup after pressing. In this pressing device, the upper mold comprises a first hollow cylinder and a second hollow cylinder in its structure, and the lower mold comprises a third hollow cylinder and a push rod. The second hollow cylinder of the upper mold moves independently vertically inside the first hollow cylinder, while the third hollow cylinder receives and holds the two cups, and the push rod is disposed in the center of the third hollow cylinder to push up the two cups.

[0009] According to this aspect, the second hollow cylinder has a flange extending from the outer surface of the second hollow cylinder and contacting the inner surface of the first hollow cylinder, thereby defining a space therebetween for accommodating at least the rims and portions of the cup bodies of the two cups, and the third hollow cylinder has curling grooves disposed at and around an upper edge of the third hollow cylinder for receiving the rims of the two cups when the two cups are accommodated therein.

[0010] According to one embodiment of the present disclosure, the third hollow cylinder has a sloped inner surface.

[0011] According to one embodiment of the present disclosure, the first and second materials are independently paper or plastic.

[0012] According to one embodiment of the present disclosure, the pressing apparatus is characterized by not having any alignment structure for positioning the two cups.

[0013] In another aspect, the present disclosure is directed to a method of joining two cups, each made of a first and second material, one of the cups having a tab extending from its rim, by utilizing the pressing apparatus described above. The method includes the steps of: (a) forming a stacked cup by placing two cups in a third hollow cylinder of a pressing device, with one cup having a tab stacked on top of the other cup without the tab; (b) pushing the stacked cups of step (a) upward with a push rod of the pressing device until the stacked cups abut a flange of the second hollow cylinder of the pressing device, such that the tabs are retracted and extend substantially downward and a rim and a portion of the cup body of the stacked cup are contained in the space between the first hollow cylinder and the second hollow cylinder; (c) driving the second hollow cylinder of the pressing device vertically downward until the rim of the stacked cup of step (b) abuts the curling groove of the third hollow cylinder; and (d) bonding the stacked cups together by rolling the rim of the stacked cup of step (c) by simultaneously applying a downward force from the second hollow cylinder and an upward force from the push rod to form a curled rim therebetween.

[0014] According to one embodiment of the present disclosure, in step (b) of the method, when the rim and a portion of the cup body of the stacked cup are received in the space between the first hollow cylinder and the second hollow cylinder, the stacked cup does not contact the third hollow cylinder.

[0015] According to one embodiment of the present disclosure, in step (c) of the method, the second hollow cylinder moves independently vertically inside the first hollow cylinder.

[0016] According to one embodiment of the present disclosure, in step (c) of the method, the stacked cups are held by a push rod.

[0017] According to one embodiment of the present disclosure, in step (d) of the method, the tab is secured within the curled rim of the laminated cup as the rim of the laminated cup is rolled.

[0018] According to one embodiment of the present disclosure, the method is characterized by eliminating rotating or positioning the stacked cups before, after or during step (a).

[0019] According to one embodiment of the present disclosure, the first and second materials are independently paper or plastic. In one preferred embodiment, the cup with the tab is made of plastic and the other cup without the tab is made of paper.

[0020] Many of the attendant features and advantages of the present disclosure will become better understood by reference to the following detailed description considered in conjunction with the accompanying drawings.

[0021] The present description will be better understood from the following detailed description read in light of the accompanying drawings. [Brief description of the drawings]

[0022] [Figure 1A] FIG. 1A is a perspective view of an exemplary pressing apparatus 1 according to one embodiment of the present disclosure. [Figure 1B] FIG. 1B is a cross-sectional view of the press device 1 of FIG. 1A. [Figure 2A] Figures 2A to 2H are schematic diagrams showing the positional states of an exemplary press apparatus 1 for performing a bonding method according to one embodiment of the present disclosure, and Figure 2A is an oblique view illustrating a stacked cup A and the upper and lower molds (11 and 12) of the press apparatus 1 in the initial position. [Figure 2B] FIG. 2B is a cross-sectional view of FIG. 2A. [Figure 2C] FIG. 2C is a perspective view illustrating the push rod 122 pushing up the stacked cup A. [Figure 2D] FIG. 2D is a cross-sectional view of FIG. 2C. [Figure 2E] FIG. 2E is a perspective view illustrating the upper mold 11 in a lowered position. [Figure 2F] FIG. 2F is a cross-sectional view of FIG. 2E. [Figure 2G] FIG. 2G is a perspective view illustrating the upper and lower molds (11 and 12) pressing together to form a curled rim for laminated cup A. [Figure 2H] FIG. 2H is a cross-sectional view of FIG. 2G. [Diagram 3] FIG. 3 is a schematic diagram illustrating a pressing device 2 according to an alternative embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] In accordance with common practice, the various components / elements depicted are not drawn to scale, but instead are drawn to best show the particular components / elements relevant to the present invention, and like numerals and designations in the various drawings are used to indicate like elements / portions.

[0024] The detailed description provided below in conjunction with the accompanying drawings is intended as a description of the present embodiment and is not intended to represent the only manner in which the present embodiment may be constructed or utilized. The description sets forth the functions of the present embodiment and the sequence of steps for constructing and operating the embodiment, although the same or equivalent functions and sequences may be accomplished by different embodiments.

[0025] 1.Definition For convenience of explanation, certain terms employed in the specification, examples, and appended claims are collected here. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

[0026] The singular forms "a," "an," and "the" are used herein to include the plural forms unless the context clearly dictates otherwise.

[0027] As used herein, the term "hollow cylinder" is intended to encompass hollow structures having long sides and hollow ends of various shapes, including, but not limited to, circular, triangular, square, and polygonal. In accordance with the present disclosure, the hollow cylinder is circular in shape so as to define a circular cup shape.

[0028] As used herein, the term "stacked cups" refers to two cups that are stacked together and maintained within a press until they are bonded together by the present method, and the stacked cups do not separate from each other throughout the bonding process of the present invention.

[0029] The terms "rimming" and "rolling / curling" are used interchangeably herein to refer to steps in the process of manufacturing disposable or recyclable cups that involve rolling the edge of the cup outward and downward to form a curved arc-shaped structure that enhances the structural strength of the cup. According to the present disclosure, the "rimming" or "rolling / curling" steps are performed simultaneously on two stacked cups so that the two edges of the stacked cups overlap and roll around each other to secure the two cups to each other.

[0030] The term "disposable cup" refers to a cup that is typically designed for single use and is made of disposable materials, such as polyethylene terephthalate (PET), polypropylene (PP), polystyrene (PS), paper, etc. However, the use of the term "disposable" does not imply that the cup must be a single-use cup, nor does it exclude the possibility that the material may be recyclable. According to the present disclosure, the "disposable material" referred to herein is substantially recyclable.

[0031] As used herein, the term "alignment structure" refers to any structure or design on the press apparatus that helps to position the tabs (i.e., position the tabs in a particular orientation). Examples of alignment structures include, but are not limited to, pins and dowels, tabs and notches, guide rails and tracks, optical alignment features (e.g., light or laser beams), etc. It is noted that the present press apparatus does not include any of the above structures.

[0032] 2. Description of the Invention The present disclosure aims to provide an improved pressing device for bonding two cups. The pressing device is specifically designed for vertically aligning and bonding two cups made of different materials, i.e., first and second materials, stacked on each other to form a double-walled cup. Notably, the pressing device does not include any alignment structure for positioning the two cups, and therefore the pressing device can produce the double-walled cup in a timely manner. Also provided herein is a method for bonding two cups by utilizing the above-mentioned pressing device.

[0033] 2.1 Press equipment Reference is now made to Figures 1A and 1B, which are a perspective view and a cross-sectional view, respectively, of a pressing apparatus 1 according to one embodiment of the present disclosure. The pressing apparatus 1 comprises an upper mold 11 and a lower mold 12, where the upper and lower molds (11 and 12) are aligned vertically and spaced apart by a certain distance. The upper mold 11 comprises in its structure a first hollow cylinder 111 and a second hollow cylinder 112, where the second hollow cylinder 112 has a flange 1121 extending from its outer surface. As shown, the second hollow cylinder 112 is preferably disposed inside the first hollow cylinder 111, so that the flange 1121 of the second hollow cylinder 112 abuts against the inner surface of the first hollow cylinder 111, thereby creating a space S therebetween during operation. Preferably, the size of the space S can be changed or adjusted as needed to the extent that the stacked cups are held therein during the bonding process. According to a preferred embodiment, the depth of the space S is greater than the length of the tab of the cup, which is explained in further detail in Figures 2A-2H.

[0034] Similarly, the lower mold 12 includes in its structure a third hollow cylinder 121 and a push rod 122, which is centrally disposed within the third hollow cylinder 121 and moves independently vertically within the third hollow cylinder 121. Moreover, the third hollow cylinder 121 further includes a curling groove 1211 disposed at its upper edge and its periphery, as shown in FIG. 1B. According to an embodiment of the present disclosure, the size (i.e., depth and width) of the curling groove 1211 can be changed or adjusted according to practical needs, for example, based on the shape or size of the rim of the cup, for the purpose of providing a normal force against the rim of the cup during the bonding process to prevent the two cups from slipping out of the apparatus. According to some alternative embodiments of the present disclosure, the third hollow cylinder 121 may have an inclined inner surface 1213 (FIG. 1B) to better conform to the shape of the cup and provide sufficient support.

[0035] The press apparatus 1 of the present disclosure can be driven by mechanisms well known in the art, such as force generated by hydraulic cylinders and hydraulic fluid (i.e., hydraulic force), force generated by a mechanical system such as a flywheel and crankshaft (i.e., mechanical force), or force generated by compressed air (i.e., pneumatic pressure) to move the upper and lower molds (11, 12) of the press apparatus 1 and thereby achieve the desired results.

[0036] 2.2 Bonding process Another aspect of the present disclosure is directed to joining two cups with the aid of a pressing device 1. Reference is now made to Figures 2A-2H which collectively show the state of the present pressing device 1 during the pressing or joining process.

[0037] Fig. 2A illustrates the upper and lower moulds (11 and 12) in their initial or rest position (i.e., the position before the pressing process starts), and Fig. 2B is a cross-sectional view of the pressing apparatus 1 of Fig. 2A. Note that in the rest position illustrated in Figs. 2A and 2B, the push rod 122 in the third hollow cylinder 121 of the lower mould 12 is in a relatively lower position. This arrangement ensures that the third hollow cylinder 121 has sufficient clearance to receive and hold a cup therein.

[0038] To start the bonding process, two cups, each made of a first and second material, are stacked to form a stacked cup (indicated as "A" in Figs. 2A-2H), and one cup with a tab (e.g., a plastic cup) is placed on top of the other cup without a tab (e.g., a paper cup) (indicated as "T" in Figs. 2A-2H). The stacked cup A is then placed on the push rod 122 in the third hollow cylinder 121 (Fig. 2B). Preferably, the stacked cup A is placed on the push rod 122 in the third hollow cylinder 121 with the rim of the stacked cup A supported or lifted by the curling groove 1211 of the third hollow cylinder 121.

[0039] 2C and 2D, FIG. 2C is a perspective view of the pressing device 1 during movement, and FIG. 2D is a cross-sectional view of the pressing device 1 of FIG. 2C. At this stage, the push rod 122 rises vertically relative to the third hollow cylinder 121, thereby pushing the stacked cups A into the space S created between the flange 1121 and the inner surface of the first hollow cylinder 111. The space S will accommodate at least the rim and part of the cup body of the stacked cups A, the flange 1121 normally abuts against the rim, and the tab T is stored downward so as to contact the inner surface of the first hollow cylinder 111 (FIG. 2D). Note that at this point, the tab T is approximately vertical to the ground. The upward movement of the push rod 122 automatically stops when the upper edge of the stacked cups A contacts the flange 1121 of the second hollow cylinder 112. Through this movement, the tab T is stored in the space S and is confined to extend substantially downward. Usually, after the stacked cup A is pushed up, the rim and part of the cup body of the stacked cup A are accommodated in the space S between the first hollow cylinder and the second hollow cylinder (111 and 112) as shown in Figures 2C and 2D. Note that at this stage, the stacked cup A is substantially separated from the third hollow cylinder 121, in other words, the stacked cup A is no longer in contact with the third hollow cylinder 121.

[0040] 2E-2H, FIGS. 2E and 2G are perspective views of the upper mold 11 of the press device 1 in the pressed-down position, and FIGS. 2F and 2H are cross-sectional views of the press device 1 of FIGS. 2E and 2G, respectively. As shown in FIG. 2D, once the tab T of the stacked cup A is retracted, the upper mold 11 can proceed to punch down until it abuts the lower mold 12 (FIG. 2G), specifically, until the first hollow cylinder 111 contacts the third hollow cylinder 121. At this point, the first hollow cylinder 111 is relatively fixed in a specific position, and the second hollow cylinder 112 continues to press down further (i.e., relative to the first hollow cylinder 111) to push the stacked cup A out of the space S, until the rim of the stacked cup A contacts the curl groove 1211 of the third hollow cylinder 121. According to some preferred embodiments, the push rod 122 of the press 1 does not leave the bottom of the stacked cup A while the upper mould 11 is being pressed down.

[0041] Once the rim of the stacked cup A is positioned within the curling groove 1211 of the third hollow cylinder 121, the second hollow cylinder 112 continues to apply a downward force while the push rod 122 simultaneously applies an upward force, curling the rim of the stacked cup A to form a curled rim, thereby joining the two cups together (FIG. 2H). According to a preferred embodiment of the present disclosure, a portion of the tab T, which is housed and trapped to extend downward as described above, is fixed within the curled rim of the stacked cup A, and the remaining portion of the tab T remains extending outwardly in a vertical direction, which acts as a pull-out point, allowing a user to grasp the tab T and pull it upward to separate the two cups (i.e., the inner and outer cups). In an alternative preferred embodiment, once the tab T is fixed to the curled rim of the stacked cup A, the outward portion of the tab T is attached and glued to the outer surface of the cup without the tab (i.e., the outer cup) (FIG. 2H).

[0042] It should be noted that the present pressing apparatus does not include any alignment structure, which eliminates the need to rotate or position the stacked cups during operation of the method.

[0043] According to an embodiment of the present disclosure, the first and second materials of the cups are disposable or recyclable materials such as plastic, paper, foam, etc. Preferably, the first and second materials are independently paper or plastic, and more preferably, the cup with the tab extending from the rim is made of plastic and the other cup without the tab is made of paper. Examples of plastic materials suitable for manufacturing the cups include, but are not limited to, polyethylene (including PE, ultra-low density polyethylene (ULDPE) and very low density polyethylene (VLDPE)), polypropylene (PP), polystyrene (PS), polyvinyl chloride (PVC), polycarbonate (PC), nylon, polyethylene terephthalate (PET), polytetrafluoroethylene (PTFE), polyurethane (PU), acrylonitrile-butadiene styrene (ABS), and combinations thereof. In an embodiment, the cup with the tab is made of PP.

[0044] It should be noted that the shape of the cup or container applicable to the present pressing apparatus for the bonding process is not limited to the circular shape as shown in Figures 2A-2H. Examples of container (e.g., cup) shapes include, but are not limited to, triangular, rectangular, and polygonal.

[0045] As a result of the above, the bonding process of the present disclosure allows for simultaneous positioning, rim forming and tab securing of the inner and outer cups within a single operating cycle.

[0046] 2.3 Alternative designs for this press Alternatively or additionally, multiple pressing devices 1 as described above in Figures 1A-2H may be assembled to form a pressing device 2 for simultaneously bonding multiple sets of stacked cups.

[0047] Referring to Fig. 3, a number of vertically aligned upper and lower molds (21, 22) are assembled in a press device 2. The number of upper and lower molds (21 and 22) in the press device 2 can be changed according to practical needs. In the illustrated example of Fig. 3, the press device 2 includes two panels of upper and lower molds (21 and 22), each panel consisting of 35 upper and lower molds (21 and 22) arranged in a 5x7 matrix, allowing 35 sets of stacked cups to be combined at the same time. More sets of stacked cups may be combined if necessary.

[0048] The present pressing apparatus 2 does not require any alignment structure because the spaces (not shown) defined within each of the upper molds 21 can accommodate the tabs of the stacked cups in different orientations when they are placed on the lower mold 12. Furthermore, misalignment of the tabs does not affect the smooth progress of the bonding process. Thus, the presently disclosed apparatus and method can bond the stacked cups in a short time, for example, the entire process can be completed within 10, 9, 8, 7, 6, 5, 4, 3, 2, or 1 seconds, preferably 1-4 seconds.

[0049] From the above, by using the pressing device of the present disclosure, two cups made of different materials, especially those with irregular rims and protruding tabs, can be smoothly and seamlessly bonded within a few seconds without the need to align them before bonding. Moreover, since it is not necessary to rotate or position the cups, the number of molds can be set according to practical needs, thereby greatly improving the efficiency of the bonding process.

[0050] It should be understood that the above description of the embodiments is given by way of example only, and that various modifications may be made by those skilled in the art. The above specification, examples and data provide a complete description of the structure and use of the exemplary embodiments of the invention. Although various embodiments of the invention have been described above with a certain degree of particularity or with reference to one or more specific embodiments, those skilled in the art may make numerous modifications to the disclosed embodiments without departing from the spirit or scope of the invention.

Claims

1. a pressing apparatus comprising an upper mold and a lower mold aligned vertically for joining two cups made of a first and a second material, respectively, and stacked together to form a double-walled cup after pressing; The upper mold includes: A first hollow cylinder; a second hollow cylinder that moves independently in a vertical direction inside the first hollow cylinder; Equipped with The lower mold comprises: a third hollow cylinder for receiving and holding the two cups; a push rod disposed at the center of the third hollow cylinder for pushing up the two cups; Equipped with the second hollow cylinder has a flange that protrudes from an outer surface of the second hollow cylinder and contacts an inner surface of the first hollow cylinder, thereby defining a space between the first hollow cylinder and the second hollow cylinder for accommodating at least a portion of the rims and cup bodies of the two cups; A press device, wherein the third hollow cylinder has an upper edge of the third hollow cylinder and a curling groove disposed around the upper edge of the third hollow cylinder for receiving the rims of the two cups when the two cups are placed therein.

2. The pressing apparatus according to claim 1 , wherein the third hollow cylinder has an inclined inner surface.

3. The pressing apparatus of claim 1 , wherein the first and second materials are independently paper or plastic.

4. 2. The pressing apparatus of claim 1, which does not have any alignment structure for positioning the two cups.

5. 13. A method of joining two cups, each made of a first and second material, by utilizing a press apparatus as claimed in claim 1, one of the two cups having a tab extending from its rim, the method comprising: (a) placing the two cups, one having a tab on top of the other cup not having the tab, into the lower mold of the press to form a stacked cup; (b) pushing up the stacked cups of step (a) by the push rod of the press device until the stacked cups abut against the flange of the second hollow cylinder of the press device, such that the tabs are stored and extend downward and the rims and a portion of the cup body of the stacked cups are accommodated in the space between the first hollow cylinder and the second hollow cylinder; (c) driving the second hollow cylinder of the pressing device vertically downward until the rim of the stacked cup of step (b) contacts the curling groove of the third hollow cylinder; (d) bonding the stacked cups together by rolling the rims of the stacked cups of step (c) by simultaneously applying a downward force from the second hollow cylinder and an upward force from the push rod to form a curled rim; A method for providing the above.

6. 6. The method of claim 5, wherein in step (b), when the rim and a portion of the cup body of the stacked cup are received in the space between the first hollow cylinder and the second hollow cylinder, the stacked cup is not in contact with the third hollow cylinder.

7. The method of claim 5 , wherein in step (c), the second hollow cylinder is moved independently longitudinally within the first hollow cylinder.

8. The method of claim 5 , wherein in step (c), the stacked cups are held by the push rod.

9. 6. The method of claim 5, wherein in step (d), the tab is secured to the curled rim of the laminated cup as the rim of the laminated cup is rolled.

10. 6. The method of claim 5, not comprising rotating or positioning the stacked cups before, after or during step (a).

11. The method of claim 5 , wherein the first and second materials are independently paper or plastic.

12. 6. The method of claim 5, wherein the cup having the tab is made of plastic and the other cup not having the tab is made of paper.

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