Adjustable dumbbell

Abstract

A dumbbell may include a handle, a first weighted portion and a second weighted portion, wherein the first weighted portion has a first cap and a first receiving space to receive one or more weighted units therein, and the second weighted portion has a second cap and a second receiving space to receive one or more weighted units therein. In one embodiment, the handle has a first threaded portion and a second threaded portion located at two opposite ends of the handle, and the first threaded portion is configured to threadedly engage with a first cap to secure the weighted units in the first receiving space, while the second threaded portion is configured is configured to threadedly engage with the second cap to secure the weighted units in the second receiving space.

What is claimed is: 
     
         1 . A dumbbell comprising a handle, a first weighted portion and a second weighted portion, and the first weighted portion and the second weighted portion are located at two opposite ends of the handle,
 wherein the first weighted portion has a first cover having a first receiving space, a first holding unit and a first cap, and the first receiving space has a first center receiving hole and a plurality of first receiving holes to receive one or more weighted units;   wherein the second weighted portion has a second cover having a second receiving space, a second holding unit and a second cap, and the second receiving space has a second center receiving hole and a plurality of second receiving holes to receive one or more weighted units; and   wherein the handle has a first threaded portion and a second threaded portion located at two opposite ends of the handle; said first threaded portion is configured to penetrate through the first center receiving hole to threadedly engaged with the first cap to secure the weighted units in the first receiving space, while the second threaded portion is configured to penetrate through the second center receiving hole to threadedly engaged with the second cap to secure the weighted units in the second receiving space.   
     
     
         2 . The dumbbell of  claim 1 , wherein the first holding unit is configured to secure one end of each of the weighted units, and the other end of each of the weighted units can be received in each of the first receiving holes of the first receiving space, while the second holding unit is configured to secure one end of each of the weighted units, and the other end of each of the weighted units can be received in each of the second receiving holes of the second receiving space. 
     
     
         3 . The dumbbell of  claim 2 , wherein the first holding unit has a first through hole that is aligned with the first center receiving hole; and a first threaded portion of the handle axially penetrates through the first through hole and the first center receiving hole, and can be threadedly engaged with the first cap to simultaneously secure the first holding unit and the weight units inside the first receiving space. 
     
     
         4 . The dumbbell of  claim 2 , wherein the second holding unit has a second through hole that is aligned with the second center receiving hole; and a second threaded portion of the handle axially penetrates through the second through hole and the second center receiving hole, and can be threadedly engaged with the second cap to simultaneously secure the second holding unit and the weight units inside the second receiving space. 
     
     
         5 . The dumbbell of  claim 1 , wherein each of the weighted units may have different weights, and the dumbbell itself may have certain weight without the weight units. 
     
     
         6 . The dumbbell of  claim 1 , wherein weighted units in either the first weighted portion or the second weighted portion can be added or removed according to a user's preference. 
     
     
         7 . The dumbbell of  claim 1 , wherein the first and second weighted portions can be symmetrically disposed at the opposite ends of the handle.