ELASTIC CORD AND PULL EXERCISER HAVING THE SAME

Abstract
A pull exerciser includes at least one attachment device, at least one positioning device coupled to the at least one attachment device, and at least one elastic cord. The positioning device includes at least one positioning hole. At least one of two ends of the elastic cord is hollow and engaged in the positioning hole. The end of the elastic cord includes an inner section and a turnback section surrounding the inner section. The end of the elastic cord and a distal end portion of the turnback section are engaged in the positioning hole. A stop is mounted in the end of the elastic cord and securely held by the inner section and the turnback section. The stop has an outer diameter larger than a diameter of the positioning hole.
Description
BACKGROUND OF THE INVENTION

1. Field of the Invention


The present invention relates to an elastic cord. The present invention also relates to a pull exerciser having such an elastic cord.


2. Description of the Related Art



FIG. 1 of the drawings illustrates a conventional pull exerciser. FIG. 2 is a sectional view of a portion of the conventional pull exerciser. The pull exerciser comprises two handles 1, a belt 2 extending through each handle 1, and an elastic cord 3. A positioning device 4 is provided to fix two ends of each belt 2 together. Each of two ends 30 of the elastic cord 3 is fixed to an associated positioning device 4. More specifically, each positioning device 4 includes a positioning member 41 having a positioning hole 411 through which an associated end 30 of the elastic cord 3 extends. As illustrated in FIG. 2, a stop 31 is inserted into each end 30 of the elastic cord 3, and a sleeve 32 is mounted around the end 30 of the elastic cord 3 and extended through the positioning hole 411 of the associated positioning member 41, thereby fixing the end 30 of the elastic cord 3.


The elastic cord 3 is substantially hollow and capable of returning to its original length when stretched and then released. Each stop 31 has a width or outer diameter larger than a diameter of the positioning hole 411, preventing the associated end 30 of the elastic cord 3 from disengaging from the associated positioning hole 411 when the elastic cord 3 is stretched. The disengagement-preventing effect is enhanced by the associated sleeve 32 that is made of rubber and that holds the associated end 30 of the elastic cord 3. However, the assembling procedures for the sleeve 32 are troublesome.


BRIEF SUMMARY OF THE INVENTION

In accordance with a first aspect of the present invention, a pull exerciser comprises at least one attachment device, at least one positioning device coupled to the at least one attachment device, and at least one elastic cord. The attachment device includes a handle. The positioning device includes at least one positioning hole. At least one of two ends of the elastic cord is hollow and engaged in the positioning hole. The end of the elastic cord includes an inner section and a turnback section surrounding the inner section. The end of the elastic cord and a distal end portion of the turnback section are engaged in the positioning hole. A stop is mounted in the end of the elastic cord and securely held by the inner section and the turnback section. The stop has an outer diameter larger than a diameter of the positioning hole.


In an example, the positioning device comprises two positioning plates each including at least one positioning hole that is in communication with outside via a reduced opening.


Preferably, the elastic cord is hollow.


Preferably, the turnback section is longer than the stop.


In accordance with a first aspect of the present invention, an elastic cord for a pull exerciser comprises a hollow end. The hollow end includes an inner section and a turnback section surrounding the inner section. A stop is mounted in the hollow end to form a bulge. The stop is securely held by the inner section and the turnback section.


Preferably, the stop is ellipsoidal or cylindrical.


Other objectives, advantages, and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.




BRIEF DESCRIPTION OF THE DRAWINGS


FIG. 1 is a perspective view of a conventional pull exerciser.



FIG. 2 is a sectional view of a portion of the conventional pull exerciser.



FIG. 3 is a perspective view of a pull exerciser in accordance with the present invention.



FIG. 4 is a sectional view of a portion of the pull exerciser in FIG. 3.



FIG. 5 is a perspective view of a modified embodiment of the pull exerciser in accordance with the present invention.



FIG. 6 is a sectional view of a portion of the pull exerciser in FIG. 5.




DETAILED DESCRIPTION OF THE INVENTION


FIG. 3 is a perspective view of a pull exerciser in accordance with the present invention. FIG. 4 is a sectional view of a portion of the pull exerciser in FIG. 3.


In this embodiment, the pull exerciser comprises two positioning devices 5, two attachment devices 6, and at least one elastic cord 71 (three in this example). Each attachment device 6 comprises a handle 62 and a length-adjustable belt 61 extending through the handle 62.


Each positioning device 5 is coupled with an associated attachment device 6 in a position opposite an associated handle 62. Each positioning device 5 includes two positioning plates 51 each having at least one positioning hole 511 (three in this example). Each positioning hole 511 is in communication with outside via a reduced opening 512. An example of the positioning device 5 is disclosed in Applicant's U.S. Pat. No. 6,676,576, the entire contents of which are incorporated herein by reference.


Each elastic cord 71 is substantially hollow and capable of returning to its original length when stretched and then released. Each elastic cord 71 includes two ends 711 and a stretchable intermediate section 712 between the ends 711. In this embodiment, each end 711 of each elastic cord 7 is extended through an associated positioning hole 511 of an associated positioning device 5.


A stop 72 is mounted in each end 711 of each elastic cord 71. Each stop 72 is preferably ellipsoidal or cylindrical. Each stop 72 is inserted into an associated end 711 of the associated elastic cord 71 via an end opening 717 of the associated end 711. Each stop 72 has an outer diameter greater than a diameter of the associated positioning hole 511. Thus, the associated end 711 of the associated elastic cord 71 is bulged and would not disengage from the associated positioning hole 511 after the elastic cord 71 passes through the positioning hole 511.


Referring to FIG. 4, each end 711 of each elastic cord 71 includes an inner section 716 and a turnback section 714 surrounding the inner section 716. The turnback section 714 has a length larger than that of the associated stop 72 in the associated end 711 for tightly holding the associated stop 72. A distal end portion 715 of the turnback section 714 is engaged in the associated positioning hole 511, reliably positioning the end 711 of the elastic cord 71 in the associated positioning device 5.


The elastic cords 71 with turnback sections 714 provide excellent resilient holding forces for reliably holding the stops 72 in place without the need of the sleeves 32 required in the conventional design. Disengagement of the stops 72 from the end openings 717 is prevented. The turnback section 714 can be easily obtained by turning the associated end 711 of each elastic cord 71 outward and backward to form a dual-layer section from the point 713.



FIG. 5 shows a modified embodiment of the pull exerciser in accordance with the present invention. FIG. 6 is a sectional view of a portion of the pull exerciser in FIG. 5.


More specifically, FIGS. 5 and 6 illustrate use of an elastic cord 71 in accordance with the present invention in the pull exerciser in FIGS. 1 and 2. The elastic cord 71 of this embodiment is identical to that in FIGS. 3 and 4. The same functions and advantages are obtained in both embodiments. The difference between the embodiment shown in FIGS. 5 and 6 and the embedment shown in FIGS. 3 and 4 is that the turnback section 714 on the associated end 711 of the elastic cord 711 in the embodiment shown in FIGS. 5 and 6 can be formed after the associated end 711 passes through the associated positioning hole 511 whereas the turnback section 714 on the associated end 711 of the elastic cord 711 in the embodiment shown in FIGS. 3 and 4 can be formed before the associated end 711 passes through the associated positioning hole 511.


It is noted that the elastic cord 71 in accordance with the present invention can be used with pull exercisers of any types. For example, the pull exerciser may include only one attachment device (with only one handle) and only one positioning device.


Although specific embodiments have been illustrated and described, numerous modifications and variations are still possible without departing from the essence of the invention. The scope of the invention is limited by the accompanying claims.

Claims
  • 1. A pull exerciser comprising: at least one attachment device comprising a handle; at least one positioning device coupled to said at least one attachment device, said at least one positioning device including at least one positioning hole; and at least one elastic cord having two ends, at least one of the ends of said at least one elastic cord being hollow and engaged in said at least one positioning hole, said at least one of the ends of said at least one elastic cord including an inner section and a turnback section surrounding the inner section, said at least one of the ends of said at least one elastic cord and a distal end portion of said turnback section being engaged in said at least one positioning hole, a stop being mounted in said at least one of the ends of said elastic one elastic cord and securely held by the inner section and the turnback section, the stop having an outer diameter larger than a diameter of said at least one positioning hole.
  • 2. The pull exerciser as claimed in claim 1 wherein said at least one positioning device comprises two positioning plates each including at least one positioning hole that is in communication with outside via a reduced opening.
  • 3. The pull exerciser as claimed in claim 1 wherein said at least one elastic cord is hollow.
  • 4. The pull exerciser as claimed in claim 1 wherein the turnback section is longer than the stop.
  • 5. An elastic cord for a pull exerciser, the elastic cord comprising a hollow end, the hollow end including an inner section and a turnback section surrounding the inner section, a stop being mounted in the hollow end to form a bulge, the stop being securely held by the inner section and the turnback section.
  • 6. The elastic cord for a pull exerciser as claimed in claim 5 wherein the inner section and a distal end portion of said turnback section are adapted to be engaged in a positioning hole of a positioning device of a pull exerciser to which the elastic cord is attached.
  • 7. The elastic cord for a pull exerciser as claimed in claim 5 wherein the turnback section has a length larger than that of the stop.
  • 8. The elastic cord for a pull exerciser as claimed in claim 5, wherein the stop is ellipsoidal or cylindrical.