Patent Publication Number: US-10787836-B2

Title: Tent pole

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     The present application claims priority to Korean Patent Application Numbers 10-2018-0084904 filed on Jul. 20, 2018 and 10-2019-0011292 filed on Jan. 29, 2019, in the Korean Intellectual Property Office, the entire disclosure of which is incorporated by reference herein. 
     BACKGROUND 
     Field of Invention 
     The present invention relates to a tent pole. 
     Discussion of Related Art 
     Generally, a tent includes a waterproof cloth and a plurality of poles for camping or temporarily staying outdoors and is formed to have a predetermined form by assembling the poles to each other. 
     Poles for a tent (hereinafter, tent pole) forms a framework to form a space inside a tent covered by a waterproof cloth being spread, and is typically formed in a cylindrical pipe form. One tent pole may be formed by coupling a plurality of poles manufactured of a high strength aluminum tube, a fiber reinforced plastic (FRP) tube, a steel tube, or the like. 
     The tent pole should maintain a state in which the poles are stably coupled to each other. 
     However, in a case in which the tent pole is bent when the tent is assembled, a continuous and repetitive bending force may be generated. Accordingly, a tensile force may be generated at a joint portion between the poles to increase a possibility of crack and damage occurrence. 
     SUMMARY 
     The present invention is directed to providing a tent pole including a joint portion with improved strength. 
     According to an aspect of the present invention, there is provided a tent pole, and each of a first pole and a second pole forming the tent pole includes a main pipe, an expanded pipe portion having an increased internal diameter from one end of the main pipe, an insert connector which is insertion-coupled to the other end of the main pipe and includes one portion exposed at an outside of the main pipe, the other end of the main pipe of the second pole is inserted into the expanded pipe portion of the first pole, and the insert connector of the second pole passes through the expanded pipe portion and is inserted into the main pipe of the first pole at a predetermined depth. 
     The tent pole may further include an inclined portion which is provided between the main pipe and the expanded pipe portion and has an internal diameter gradually increased from one end of the main pipe, and the insertion of the main pipe of the second pole may be restricted due to the inclined portion of the first pole. 
     The insert connector may include an inserted portion inserted into the main pipe, and an exposed portion exposed at the outside of the main pipe. 
     A length of the inserted portion may be greater than that of the expanded pipe portion. 
     A length of the inserted portion may be greater than that of the exposed portion. 
     The insert connector may be bond-coupled or forcibly press-fitted to the main pipe. 
     The main pipe may have a predetermined external diameter and a predetermined internal diameter. 
     A thickness of the insert connector may be greater than that of the main pipe. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and other objects, features and advantages of the present invention will become more apparent to those of ordinary skill in the art by describing exemplary embodiments thereof in detail with reference to the accompanying drawings, in which: 
         FIG. 1  is a view illustrating a tent in which tent poles according to one embodiment of the present invention is used; 
         FIGS. 2 to 4  are cross-sectional views illustrating tent poles according to the related art; 
         FIGS. 5A to 5C  are cross-sectional views illustrating the tent pole according to one embodiment of the present invention; 
         FIG. 6  is a view showing an experimental example of the tent pole according to the present invention; and 
         FIG. 7  is a view showing an experimental example of tent poles according to the related art. 
     
    
    
     DETAILED DESCRIPTION 
     Purposes, specific advantages, and novel features of the present invention will be clear from exemplary embodiments and the following detailed descriptions in connection with the accompanying drawings. In this specification, when reference numerals are assigned to components of each drawing, it should be noted that, the same numerals are assigned to the same components even when the same components are illustrated in different drawings whenever possible. In descriptions of the present invention, when detailed descriptions of related well-known technology are deemed to unnecessarily obscure the gist of the present invention, they will be omitted. 
     Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings in detail. 
     For convenience of explanation, the term ‘one end’ used in the specification refers to a right end of a main pipe ( 11 ,  21 ,  31 ,  33 , or  36 ) as shown in  FIG. 2 , and the ‘the other end’ refers to a left end thereof as shown in  FIG. 2 . However, the present invention is not limited thereto. 
       FIG. 1  is a view illustrating a tent in which tent poles according to one embodiment of the present invention is used. 
     Referring to  FIG. 1 , a tent  1  includes a fabric sheet  2  having a predetermined form, for example, a dome form, and tent poles  3 . As illustrated in  FIG. 1 , the plurality of tent poles  3  may be connected to each other to form a structure corresponding to the fabric sheet  2 , or the tent poles  3  connected in series may be bent to correspond to the shape of the fabric sheet  2 , and inserted into connecting rings  4  of the fabric sheet  2  to maintain a predetermined form of the fabric sheet  2  due to an elastic force of each of the tent poles  3 . 
     Here, the tent  1  may have various forms according to a use and a structure, and a detailed description thereof will be omitted. In the present embodiment, the form of the tent  1  is shown as an example, and the present invention may be applied to any structure capable of using the tent pole  3 . 
       FIGS. 2 to 4  are cross-sectional views illustrating tent poles according to the related art. 
     For the sake of convenience, a connecting portion between two poles which are adjacent among a plurality of poles included in the tent poles is illustrated in each of the following drawings, but the tent pole may have a connecting structure in which illustrated structures are repeated in a longitudinal direction. 
     In addition, since the plurality of poles forming the tent poles actually have the same structure, repeated descriptions will be omitted and one pole will be mainly described. 
     The tent pole according to the related art generally has one of the following three forms. 
     1) Standard Pipe 
     Referring to  FIG. 2 , a tent pole  3   a  having a standard pipe structure includes main pipes  31 , in which each pole has a predetermined external diameter, and has a structure in which two main pipes  31  are connected by a connector  32 . 
     The main pipe  31  has a cylindrical form which does not include an expanded or shrunken pipe portion, has the predetermined external diameter, and straightly extends. 
     One portion of the connector  32  is coupled to an end of the main pipe  31 , and the other part of the connector  32  is inserted into the main pipe  31  of another pole. That is, two poles are coupled by the connector  32 . 
     In a state in which the connector  32  is connected to the end of the main pipe  31 , the connector  32  may be inserted into the main pipe  31  of another pole. Here, the connector  32  may be connected to the main pipe  31  through a press-fitting, bonding, or punching method. 
     Since the tent pole  3   a  according to the present embodiment is easy to manufacture and wages therefor are low, the tent pole  3   a  has been most widely used. 
     2) Two-Way Expanded Pipe 
     Referring to  FIG. 3 , a tent pole  3   b  having a two-way expanded pipe structure has a structure in which an expanded pipe portion  34  is formed on an end of a main pipe  33  and a connector  35  is inserted into expanded pipe portions  34  of two poles. 
     The expanded pipe portions  34  may be formed to have the same structure on both ends of the main pipe  33 . 
     The expanded pipe portion  34  is a portion having an increased internal diameter from one end of the main pipe  33 . That is, an internal diameter of the expanded pipe portion  34  is greater than that of the internal diameter of the main pipe  33 , and the internal diameter of the expanded pipe portion  34  may have a size corresponding to an external diameter of the connector  35 . 
     A part of the connector  35  is coupled to the expanded pipe portion  34 , and the other part of the connector  35  is inserted into the expanded pipe portion  34  of another pole. That is, the expanded pipe portions  34  of two poles are coupled to each other by the connector  35 . 
     In a state in which the connector  35  is connected to the expanded pipe portion  34  of any one pole, the connector  35  may be inserted into the expanded pipe portion  34  of another pole. Here, the connector  35  is typically connected to the expanded pipe portion  34  through press-fitting or bonding. 
     In the tent pole  3   b  according to the present embodiment, since the external diameter of the connector  35  is large, a strength of a joint portion is high when compared to the standard pipe product, but a problem of cracks may occur at an end of the expanded pipe portion  34 . 
     In order to supplement this problem, a ring may also be inserted into the tent pole  3   b.  
         3) Expanded &amp; Shrunken Pipe       

     Referring to  FIG. 4 , a tent pole  3   c  having an expanded and shrunken pipe structure has a structure in which an expanded pipe portion  37  is formed from one end of a main pipe  36 , a shrunken pipe portion  38  is formed from the other end, and the expanded pipe portion  37  and the shrunken pipe portion  38  of two poles are coupled. 
     The expanded pipe portion  37  is a portion having an increased internal diameter from one end of the main pipe  36 , and the shrunken pipe portion  38  is a portion having a decreased internal diameter from the other end of the main pipe  36 . The internal diameter of the expanded pipe portion  37  has a size corresponding to the external diameter of the shrunken pipe portion  38 , and the external diameter of the shrunken pipe portion  38  has a size corresponding to the internal diameter of the expanded pipe portion  37 . 
     The tent pole  3   c  according to the present embodiment has advantages in that a wage for press-fitting is saved and a weight is reduced because a connector is omitted. 
     Other products having other structures other than the above-described three tent poles  3   a ,  3   b , and  3   c  may be present. However, products advanced from the group including the three products have not been come out yet. 
     Particularly, when each of the tent poles is bent, a tensile force is generated at the end of the connector, the joint portion between the main pipe and the expanded pipe portion or between the expanded pipe portion and the shrunken pipe portion, and the like, thereby causing a crack point. 
       FIGS. 5A to 5C  are cross-sectional views illustrating a tent pole according to one embodiment of the present invention. 
     Referring to  FIGS. 5A, 5B, and 5C , a tent pole  3  according to one embodiment of the present invention has a structure in which a plurality of poles are coupled in a longitudinal direction, and two poles which are coupled among the plurality of poles refer to a first pole  10  and a second pole  20 . 
     In addition, since the first pole  10  and the second pole  20  have the same structure, repeated descriptions will be omitted and the first pole  10  will be mainly described. 
     In addition, the tent pole  3  may have a structure in which an elastic strap (not shown) passes through insides of the plurality of poles so that the poles are connected to each other even in a state in which the poles are separated from each other. 
     The first pole  10  may include a main pipe  11 , an expanded pipe portion  13 , an inclined portion  14 , and an insert connector  15 . 
     The main pipe  11  is a pipe forming a body of the pole, may have a cylindrical pipe form having predetermined external and internal diameters, and may be manufactured of high strength aluminum, fiber reinforced plastic (FRP), steel, or carbon. 
     For example, the main pipe  11  may have an external diameter D 1  of 8.5 mm, an internal diameter of 7.1 mm, and a length of 200 mm. 
     The expanded pipe portion  13  is a portion having an increased internal diameter from one end of the main pipe  11 . That is, the internal diameter of the expanded pipe portion  13  is greater than that of the main pipe  11 , and the internal diameter of the expanded pipe portion  13  may have a size corresponding to the external diameter of the main pipe  11 . The expanded pipe portion  13  and the main pipe  11  may be formed of the same material and have an integrated structure. 
     For example, the expanded pipe portion  13  may have an external diameter D 2  of 10 mm, an internal diameter of 8.6 mm, and a length L 1  of 30 mm. 
     The inclined portion  14  is provided between the main pipe  11  and the expanded pipe portion  13 , and has a tapered form having a gradually increasing internal diameter from one end of the main pipe  11 . However, an angle of the inclined portion  14  may be variously set gently or sharply as necessary. 
     The insert connector  15  is insertion-coupled to the other end of the main pipe  11 , and a portion of the insert connector  15  is exposed at an outside of the main pipe  11 . That is, the insert connector  15  is coupled to a side opposite to the expanded pipe portion  13 , and a portion of the insert connector  15  is inserted into the main pipe  11 , and the other portion is exposed at the outside of the main pipe  11 . 
     A material of the insert connector  15  may be the same as that of the main pipe  11 , and the insert connector  15  and the main pipe  11  may be separate parts which are separately manufactured. The separately manufactured insert connector  15  may be bond-coupled or forcibly press-fitted to the main pipe  11 . 
     In order to insert the insert connector  15  into the main pipe  11 , an external diameter of the insert connector  15  may have a size corresponding to the internal diameter of the main pipe  11 . In addition, in order to improve strength, a thickness of the insert connector  15  may be greater than that of the main pipe  11 . 
     For example, the insert connector  15  may have an external diameter D 3  of 7 mm, an internal diameter of 5 mm, and a length L 2  of 60 mm. 
     The insert connector  15  may include an inserted portion  15   a  inserted into the main pipe  11  and an exposed portion  15   b  exposed at the outside of the main pipe  11 . That is, the inserted portion  15   a  is one portion, which is inserted into the main pipe  11 , of the insert connector  15 , and the exposed portion  15   b  is another portion, which is not inserted into the main pipe  11  and is exposed at the outside, of the insert connector  15 . 
     According to one embodiment, a length L 3  of the inserted portion  15   a  may be greater than the length L 1  of the expanded pipe portion  13 . In addition, the length L 3  of the inserted portion  15   a  may be greater than a length of the exposed portion  15   b.    
     For example, in a case in which the expanded pipe portion  13  has the length L 1  of 30 mm, and the insert connector  15  has the entire length L 2  of 60 mm, the inserted portion  15   a  may have the length L 3  of 40 mm, and the exposed portion  15   b  may have a length of 20 mm. 
     Hereinafter, an example will be described in which the first pole  10  and the second pole  20  are coupled. Here, the second pole  20  and the first pole  10  have the same structure. 
     Referring to  FIGS. 5B and 5C , the other end of a main pipe  21  of the second pole  20  is inserted into the expanded pipe portion  13  of the first pole  10 . At this moment, an insert connector  25  has been coupled to the main pipe  21  of the second pole  20 . When the first pole  10  and the second pole  20  are coupled, the insert connector  25  of the second pole  20  passes through the expanded pipe portion  13  of the first pole  10  and is inserted into the main pipe  11  of the first pole  10  at a predetermined depth. 
     In a state in which the main pipe  21  of the second pole  20  is inserted into the expanded pipe portion  13  of the first pole  10 , an end of the main pipe  21  is guided along an inside of the expanded pipe portion  13  to be smoothly inserted thereinto. In addition, the insertion of the main pipe  21  of the second pole  20  is restricted due to the inclined portion  14  of the first pole  10 . 
     When the first pole  10  and the second pole  20  are completely coupled, one portion of the insert connector  25  of the second pole  20  and the main pipe  21  of the second pole  20  are supportedly disposed inside the expanded pipe portion  13  of the first pole  10 , and the other portion of the insert connector  25  is supportedly disposed inside the main pipe  11  of the first pole  10 . 
     According to such a coupling structure, a state in which the first pole  10  and the second pole  20  are stably coupled is maintained, and the insert connector  25  of the second pole  20  also covers all of total and surrounding regions of the expanded pipe portion  13  of the first pole  10 , that is, an end portion of the first pole  10  and an end portion of the second pole  20  which have high risks of cracks due to bending. 
     That is, the tent pole  3  according to the present invention serves to distribute a force by double supporting an area which is larger than that of a structure of each of the tent poles  3   a ,  3   b , and  3   c.    
     As described above, the connecting structure of the tent pole  3  according to the present invention reinforces a connecting portion between the poles using the insert connector when compared to a connecting structure of the conventional tent pole, and thus a strength of a joint portion can be improved to prevent cracks and damage. 
       FIG. 6  is a view showing an experimental example of the tent pole according to the present invention, and  FIG. 7  is a view showing an experimental example of tent poles according to the related art. 
     Referring to  FIGS. 6 and 7 , the results of tensile tests for comparing strengths of connecting portions of tent poles are shown in tables. Here, Si denotes the tent pole  3  according to the present invention, S 3  refers to the tent pole  3   a  having the standard pipe structure, and S 4  denotes the tent pole  3   c  having the expanded and shrunken pipe structure. 
     When the result values (maximum load and load at yield) of Si, S 3 , and S 4  are compared on the basis of the tensile tests performed a plurality of times, it may be seen that Si had the largest values and was highest from a view point of strength. 
     Specifically, in the tent poles S 3  and S 4  according to the related art, when the tent poles were bent in certain forms, there was a problem in that the connecting portion between the poles, and portions from which the pipe was expanded and shrunken were bent and damaged, or coupling forces thereof were decreased. 
     However, in the tent pole Si according to the present invention, since the insert connector was deeply inserted into the expanded pipe portion and the main pipe, a contact area was increased, and even when the tent pole  3  was bent, a force applied to the connecting portion was distributed to the expanded pipe portion and the main pipe, and also distributed to the insert connector which was supportedly disposed inside the expanded pipe portion and the main pipe, and thus bending properties were improved and a lifespan of a product was able to be increased. 
     As described above, in a tent pole according to the present invention, since a connecting portion between poles is widened and reinforced using an insert connector, the strength of a joint portion is improved to prevent cracks and damage. 
     In addition to the above-described embodiment, the present invention includes any embodiment derived by combining at least one of the embodiments and a known technology or combining at least two of the embodiments. 
     The present invention has been described in detail with reference to the exemplary embodiments. However, the exemplary embodiments should be considered in a descriptive sense only, and the present invention is not limited thereto. It should be clear to those skilled in the art that various modifications and improvements within the scope of the invention may be made. 
     Simple modifications and alterations of the present invention fall within the scope of the present invention which is defined by the accompanying claims.