1. Field of the Invention
The present invention relates to a pull exerciser having at least one replaceable resilient cord.
2. Description of the Related Art
U.S. Pat. No. 6,676,576 discloses an adjustable pull exerciser including two attachment members, two handles respectively mounted on the attachment members, and at least one resilient cord attached between the attachment members. The resilient cord can be replaced with a new one when desired. Two positioning devices are respectively attached to the attachment members and each include a first positioning plate and a second positioning plate. Each of the first positioning plate and the second positioning plate includes at least one positioning hole in communication with outside via a reduced opening having a width smaller than a diameter of the positioning hole. The resilient cord is so sized to be extendible through the positioning holes of the first and second positioning plates. An end piece is fixed to each end of the resilient cord and has a diameter greater than that of the positioning holes of the first and second positioning plates. Each attachment is adjustable in length to allow the associated first positioning plate and the associated second positioning plate to be spaced apart from each other for allowing removal/mounting of the resilient cord and to allow the associated first positioning plate to be in contact with the associated second positioning plate after removal/mounting of the resilient cord. However, when the resilient cord is subject to a relatively large force during use, the respective first positioning plates are liable to be spaced apart from or to turn relative to the respective second positioning plates, resulting in undesired disengagement of the resilient cord.
An object of the present invention is to provide an adjustable pull exerciser comprising at least one resilient cord that is reliably positioned while allowing a user to replace the resilient cord with another resilient cord having a different elastic coefficient.
Another object of the present invention is to provide an adjustable pull exerciser that has a plurality of reliably positioned resilient cords while allowing a user to attach additional resilient cords to or remove some of resilient cords from the pull exerciser when desired.
In accordance with an aspect of the present invention, a pull exerciser comprises two attachment members each having a grip portion, two positioning devices respectively attached to the attachment members at a location opposite to the grip portion of an associated one of the attachment members, and at least one resilient cord.
Each positioning device includes a positioning block and a positioning plate removably received in the positioning block. Each of the positioning blocks and the positioning plates includes at least one positioning hole. The resilient cord has two ends extendible through the positioning hole of each positioning block and each positioning plate. An end piece is fixed to each end of the resilient cord. The end pieces of the resilient cord are mounted to at least one of the positioning plates.
Preferably, each positioning block comprises a compartment for fittingly receiving an associated positioning plate.
Preferably, each attachment member is a belt, and the pull exerciser further comprises a tubular handle mounted around each belt.
Preferably, each positioning block comprises two slots in two sides thereof, and each belt extends through the slots of an associated positioning block.
Preferably, each attachment member is adjustable in length.
In a first example of the invention, the positioning hole of each positioning block has a diameter greater than that of the end pieces of the resilient cord.
In a second example of the invention, the positioning hole of each positioning block has a diameter smaller than that of the end pieces of the resilient cord. The positioning hole of each positioning block is communicated with outside via a reduced opening having a width smaller than a diameter of the positioning hole of each positioning block, allowing the resilient cord to be inserted into the positioning hole of each positioning block via the reduced opening of the positioning hole of each positioning block.
In a modified embodiment of the first example of the invention, each positioning block further comprises at least one second positioning hole having a diameter smaller than that of the end pieces of the resilient cord. The second positioning hole of each positioning block is communicated with outside via a reduced opening having a width smaller than a diameter of the second positioning hole of each positioning plate, allowing the resilient cord to be inserted into the second positioning hole of each positioning block via the reduced opening of the second positioning hole of each positioning block.
Preferably, the positioning hole of each positioning plate has a diameter smaller than that of the end pieces of the resilient cord. The positioning hole of each positioning plate is communicated with outside via a reduced opening having a width smaller than a diameter of the positioning hole of each positioning plate, allowing the resilient cord to be inserted into the positioning hole of each positioning plate via the reduced opening.
Preferably, each reduced opening of the positioning hole of each positioning plate faces in a direction opposite to that of an associated reduced opening of an associated positioning block.
In accordance with another aspect of the present invention, a pull exerciser comprises two tubular handles, two length-adjustable belts each extending through an associated tubular handle, two positioning devices respectively attached to the belts at a location opposite to an associated tubular handle, and a plurality of resilient cords.
Each positioning device includes a positioning block and a positioning plate removably received in the positioning block. Each of the positioning blocks and the positioning plates has a plurality of positioning holes. Each positioning hole of each positioning plate is communicated with outside via a reduced opening having a width smaller than a diameter of each positioning hole of each positioning plate.
Each of two ends of each resilient cord is insertable into an associated one of the positioning holes through the reduced opening of the associated positioning hole. Each resilient cord is extendible through the positioning holes of each positioning block. An end piece is fixed to each end of each resilient cord and has a diameter greater than the diameter of each positioning hole of the positioning plates. At least one of the resilient cords is selectively attached to the positioning devices.
Preferably, the resilient cords have different elastic coefficients.
Preferably, each positioning hole of each positioning plate is aligned with an associated positioning hole of an associated positioning block.
Preferably, each attachment member is adjustable in length.
In a first example of the invention, each positioning hole of each positioning block has a diameter greater than that of the end pieces of each resilient cord.
In a second example of the invention, each positioning hole of each positioning block has a diameter smaller than that of the end pieces of each resilient cord. Each positioning hole of each positioning block is communicated with outside via a reduced opening having a width smaller than a diameter of each positioning hole of each positioning block, allowing each resilient cord to be inserted into the positioning holes of the positioning blocks via the reduced opening of each positioning hole of each positioning block.
Preferably, each reduced opening of each positioning plate faces in a direction opposite to that of an associated reduced opening of an associated positioning block.
In a third example of the invention, at least one of the positioning holes of each positioning block has a diameter smaller than that of the end pieces of each resilient cord. The at least one of the positioning holes of each positioning block is communicated with outside via a reduced opening having a width smaller than a diameter of each positioning hole of each positioning block, allowing an associated resilient cord to be inserted into the at least one of the positioning holes of the positioning blocks via the reduced opening of the at least one of the positioning hole of each positioning block. At least one of the remaining positioning holes of each positioning block has a diameter greater than that of the end pieces of the resilient cords.
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.
Referring to
Referring to
Each positioning block 41 includes at least one positioning hole 411, and each positioning plate 42 includes at least one positioning hole 421. In the illustrated embodiment, each positioning block 41 includes three positioning holes 411, and each positioning plate 42 includes three positioning holes 421 respectively aligned with the positioning holes 411 of the associated positioning block 41. Further, each positioning hole 411 of each positioning block 41 has a diameter greater than that of the end pieces 33 of the resilient cords 3, allowing the resilient cords 3 to directly extend through the positioning holes 411. Each positioning hole 421 of each positioning plate 42 has a diameter smaller than that of the end pieces 33 of the resilient cords 3. Further, each positioning hole 421 is communicated with outside via a reduced opening 422 having a width smaller than the diameter of the positioning hole 421.
Each end 31, 32 of each resilient cord 3 that has extended through the positioning holes 411 can be inserted into an associated positioning hole 421 of the associated positioning plate 42, with each end piece 33 being partially extended into an associated positioning hole 421, as shown in
The user may grip the handles 52 and pull the resilient cords 3 for exercise purposes, as shown in
Since the positioning plates 42 are received in the positioning blocks 41 after assembly, the positioning plates 42 could not turn in or disengage from the positioning blocks 41. Further, the positioning devices 4 are improved in strength and thus prolong the life of the pull exerciser.
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.