Abstract:
A heat-insulating paper cup allows the glued external wall of the heat-insulating tube to be formed with a smooth surface, and the raised lines on the inner wall of the heat-insulating tube are mated closely with the conical cylindrical wall of the cup body. This can facilitate advertisement printing and fabrication on the surface of heat-insulating paper cup. Moreover, the raised lines on the inner wall of the heat-insulating tube can support the ribs, thus enhancing the structural strength and robustness of the heat-insulating tube and avoiding squashing during manual holding.

Description:
CROSS-REFERENCE TO RELATED U.S. APPLICATIONS 
       [0001]    The present application is a continuation-in-part of U.S. application Ser. No. 12/691,381, filed on Jan. 21, 2010, and entitled HEAT-INSULATING PAPER CUP”, presently pending. 
     
    
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
       [0002]    Not applicable. 
       NAMES OF PARTIES TO A JOINT RESEARCH AGREEMENT 
       [0003]    Not applicable. 
       REFERENCE TO AN APPENDIX SUBMITTED ON COMPACT DISC 
       [0004]    Not applicable. 
       BACKGROUND OF THE INVENTION 
       [0005]    1. Field of the Invention 
         [0006]    The present invention relates generally to a heat-insulating paper cup, and more particularly to an innovative one which allows raised lines to be set on the inner wall of the heat-insulating tube and mated closely with the cup body. 
         [0007]    2. Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 37 CFR 1.98 
         [0008]    Since conventional a single-layer paper cup filled with hot drink or water makes it difficult to hold manually, a heat-insulating paper cup has been developed in the industry. Said heat-insulating paper cup is structurally designed in such a manner that an external paper tube is generally sleeved onto exterior of original cup body, so a two-layer wall is employed for heat insulation. Yet, there still exist the following shortcomings against conventional heat-insulating paper cup. 
         [0009]    As for the typical structure wherein the external paper tube is made of corrugated paper and spaced ribs are set on the external wall, the heat-insulating effect can be enhanced by the bigger thickness of the external paper tube with spaced ribs, but the irregular surface formed by the spaced ribs leads to difficult advertisement printing and fabrication on the surface of the heat-insulating paper cup. 
         [0010]    Moreover, upper and lower flanges of the external paper tube are designed into an incurved shape to form an annular space of better insulation effect between the external paper tube and cup body of conventional heat-insulating paper cup. Yet, it is observed during actual application that, only incurved portions of the upper and lower flanges of external paper tube are used as a support, a vacant shell is formed between the intermediate region of the external paper tube and the cup body, so the external paper tube is easily squashed when it is held manually. 
         [0011]    There still exists another shortcoming against conventional heat-insulating paper cup: when these paper cups are overlapped, the conical cylindrical wall of two heat-insulating paper cups usually enters into a pressing state, abutting cannot be realized due to spacing between the bottoms of the cups, so the overlapped paper cups will enter into a tighter pressing state with the overlapping time, leading to inconvenient use by the users. As for heat-insulating paper cups with spaced ribs made of corrugated paper, the spaced ribs on the external paper tube will be squashed and deformed by excessive pressing, and the heat-insulating space will be reduced, affecting the heat-insulating effect directly. 
         [0012]    Moreover, notwithstanding the insulation effect of conventional heat-insulating paper cup is achieved by said external paper tube, the original single-layer paper wall for the bottom structure is still maintained without any change of the design. So, when a hot or warm drink is filled, the cup bottom is a relatively weak part of the overall cup structure for heat insulation and preservation, requiring for breakthrough improvement. 
         [0013]    Thus, to overcome the aforementioned problems of the prior art, it would be an advancement if the art to provide an improved structure that can significantly improve the efficacy. 
         [0014]    Therefore, the inventor has provided the present invention of practicability after deliberate design and evaluation based on years of experience in the production, development and design of related products. 
       BRIEF SUMMARY OF THE INVENTION 
       [0015]    The enhanced efficacy of the present invention is as follows: 
         [0016]    Based on the unique design of the present invention wherein the “heat-insulating paper cup” allows the glued external wall of heat-insulating tube to be designed with a smooth surface, and the raised lines on the inner wall of the heat-insulating tube are mated closely with the conical cylindrical wall of the cup body, this can facilitate advertisement printing and fabrication on the surface of heat-insulating paper cup. Moreover, the raised lines on the inner wall of the heat-insulating tube can support the ribs, thus enhancing the structural strength and robustness of the heat-insulating tube and avoiding squashing during manual holding. 
         [0017]    The improvements brought about by this invention are as follows: 
         [0018]    Based on the structural design wherein the raised line is designed into an oblique angle, the flow speed of glue can be delayed to prevent dripping of the glue. 
         [0019]    Based on the structural characteristics of the second cup bottom and bottom extension folded edge, an extended strengthening structure is formed at the bottom of the annular underframe of the cup bottom. When cup bodies are overlapped, the bottom extension folded edge on the cup body is abutted onto the cup bottom of the cup body before the conical cylindrical walls of two cup bodies are abutted to each other. In this case, the cup body will not continue to fall, thus preventing excessive pressing of the conical cylindrical walls of the cup bodies and facilitating the use of the paper cups. Besides, raised lines on the inner wall of the heat-insulating sleeve can also be prevented from deformation by extruding to ensure the expected and best heat-insulating effect. 
         [0020]    With the setting of the second cup bottom, another bottom structure could be formed at interval at the cup bottom of the cup body, helping to make up the shortcomings of the original cup bottom such as: single-layer structure and week heat preservation effect, and significantly improve the bottom&#39;s structural strength and heat-insulating effect of the heat-insulating paper cups. 
         [0021]    Although the invention has been explained in relation to its preferred embodiment, it is to be understood that many other possible modifications and variations can be made without departing from the spirit and scope of the invention as hereinafter claimed. 
     
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
         [0022]      FIG. 1  shows an assembled perspective view of a preferred embodiment of the present invention. 
           [0023]      FIG. 2  shows an exploded perspective view of a preferred embodiment of the present invention. 
           [0024]      FIG. 3  shows an unfolded view of the heat-insulating tube of the present invention. 
           [0025]      FIG. 4  shows a plane top view of a preferred embodiment of the present invention. 
           [0026]      FIG. 5  shows a flow process diagram of the present invention. 
           [0027]      FIG. 6  shows a schematic view of the present invention that the raised line is of a wavy pattern. 
           [0028]      FIG. 7  shows an assembled sectional view of the preferred embodiment of the present invention. 
           [0029]      FIG. 8  shows an enlarged view of part B shown in  FIG. 7 . 
           [0030]      FIG. 9  shows a plan view of two overlapped paper cup bodies of the present invention. 
           [0031]      FIG. 10  shows an application view of the present invention wherein a curved retracted section is formed on the upper part of the second cup bottom&#39;s annular side frame. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0032]      FIGS. 1-4  and  7 - 8  depict preferred embodiments of a heat-insulating paper cup of the present invention, which, however, are provided for only explanatory objective for patent claims. 
         [0033]    Said heat-insulating paper cup comprises a cup body  10 , which comprises a conical cylindrical wall  11 , a cup bottom  12  and a cup rim  13 . Of which a downward protruding annular underframe  121  is formed at the joint of the cup bottom  12  and the bottom of the conical cylindrical wall  11 . 
         [0034]    A glued heat-insulating tube  20  is made of paper material. The inner wall  21  of the heat-insulating tube  20  is sleeved onto the exterior of the conical cylindrical wall  11  of the cup body  10 , and the heat-insulating tube  20  and the conical cylindrical wall  11  of the cup body  10  are adhered securely by glue W (shown in  FIG. 4 ). The heat-insulating tube  20  is of conical cylindrical shape and mated with the conical cylindrical wall  11 . Moreover, the external wall  22  of the heat-insulating tube  20  is designed with a smooth surface, so this can facilitate advertisement printing and fabrication on the surface of heat-insulating paper cup, thus increasing the visibility of the business performance and improving the value of the products. Meanwhile, the users are allowed to hold stably the heat-insulating tube  20  which can prevent efficiently heat transfer and avoid the scalding of hot liquid stored in the cup body  10  to ensure the safety of utilization. 
         [0035]    Multiple raised lines  23  are protruded at interval onto the inner wall  21  of the heat-insulating tube  20  at an oblique angle, and mated with the conical cylindrical wall  11  of the cup body  10 . Said raised line  23  permits to reduce the contact area with the cup body  10 , helping to cut down efficiently the heat transfer. 
         [0036]    Multiple hollow ducts  24 , set into the heat-insulating tube  20  at interval and at an oblique angle in tune with the raised lines  23 . 
         [0037]    Referring to  FIGS. 2 ,  7  and  8 , a second cup bottom  30  is located at the bottom of annular underframe  121  of the cup bottom  12 , so that an interval space  40  is formed between second cup bottom  30  and cup bottom  12 ; and an annular side frame  31  folded downwards is set on the periphery of the second cup bottom  30 , and also located below the annular underframe  121  of the cup bottom  12 . 
         [0038]    Referring to  FIGS. 2 ,  7  and  8 , a bottom extension folded edge  50  is extended downwards from the bottom of the heat-insulating sleeve  20 ; said bottom extension folded edge  50  is also located beyond the annular underframe  121  of the cup body  10  and the annular side frame  31  of the second cup bottom  30 . The lower end of bottom extension folded edge  50  is folded inwards and upwards to form a folded flange  51 , which is abutted to the inner side of annular side frame  31  of the second cup bottom  30 . 
         [0039]    Of which, the heat-insulating tube  20  is made of corrugated paper, so the corrugated inner layer of the corrugated paper is defined to form said raised line  23  and hollow duct  24 . Said hollow duct  24  will then be ventilated to avoid vacuum suction due to tight sleeving between annular space of heat-insulating paper cup, and enable easier removal of the closely overlapped heat-insulating paper cups. 
         [0040]    Of which, said raised line  23  is available with multiple patterns. Referring to  FIGS. 2 and 3 , said raised line  23  is extended obliquely from the top to the bottom of the heat-insulating tube  20 . Or, referring to  FIG. 6 , said raised line  23  is extended transversely into a wavy pattern between the top and bottom of the heat-insulating tube  20 . 
         [0041]    Based on above-specified structural design, said heat-insulating paper cup is formed by the steps in  FIG. 5 , wherein the unfolded heat-insulating tube  20  is folded into a conical cylindrical pattern in tune with the cup body  10 , and the inner wall  21  of the conical cylindrical heat-insulating tube  20  is coated with glue W. Next, the cup body  10  is sleeved onto it such that the heat-insulating tube  20  and the conical cylindrical wall  11  of the cup body  10  are adhered by glue W (in conjunction with  FIG. 4 ). 
         [0042]    Referring also to  FIG. 8 , the second cup bottom  30  is abutted to the bottom of the annular underframe  121  of cup bottom  12 , and then the bottom extension folded edge  50  is folded. Based on the structural characteristics of said second cup bottom  30  and the bottom extension folded edge  50 , an extended strengthening structure is formed at the bottom of the annular underframe  121  of the cup bottom  12 . Therefore, referring to  FIG. 9 , when another cup body  10 B is overlapped onto the cup body  10 , since the bottom of the cup body  10 B is higher than the conventional paper cup (marked by W), the bottom extension folded edge  50  on the cup body  10 B is abutted onto the cup bottom  12  of the cup body  10  before the conical cylindrical walls  11  of two cup bodies  10 ,  10 B are abutted to each other. In this case, the cup body  10 B will not continue to fall, thus preventing excessive pressing of the conical cylindrical walls  11  of the cup bodies  10  and  10 B. And multiple raised lines  23  set on the inner wall  21  of the heat-insulating sleeve  20  can also be prevented from deformation by extruding to ensure the expected and best heat-insulating effect. With the setting of the second cup bottom  30 , another bottom structure could be formed at interval at the cup bottom  12  of the cup body  10 , helping to make up the shortcomings of the original cup bottom  12  such as: single-layer structure and week heat preservation effect, and significantly improve the bottom&#39;s structural strength and heat preservation effect of the heat-insulating paper cups. 
         [0043]    Referring also to  FIG. 10 , a curved retracted segment  315  is formed on the upper part of the annular side frame  31  of the second cup bottom  30 , and also abutted to the inner side of annular underframe  121  at the cup bottom  12  of the cup body  10 . In the preferred embodiment, outer diameter difference exists at the upper and lower parts of the annular side frame  31  of the second cup bottom  30  with the setting of the curved retracted segment  315 , so that the mating of the second cup bottom  30  and the annular underframe  121  has embedded positioning effect, which is more conducive to stability and smoothness in the mating process.