Adjustable dumbbell

Abstract

The present invention relates to an adjustable dumbbell, which includes a dumbbell body and dumbbell pieces cumulatively attached to both ends of the dumbbell body, wherein the dumbbell body includes a grip rod and mounting portions, further includes a first telescopic rod and a second telescopic rod, the number of dumbbell pieces hanging on the first telescopic rod and the second telescopic rod is controlled by the first telescopic rod and the second telescopic rod extending from or retracting into both ends of the dumbbell body in opposite directions, thereby adjusting the weight of dumbbells. The first telescopic rod and the second telescopic rod are disposed in a semicircular shaft shape, and the first telescopic rod and the second telescopic rod are staggered, so that the lengths of the first telescopic rod and the second telescopic rod are doubled, and the number of adjustable dumbbell pieces is greatly increased.

What is claimed is: 
     
         1 . An adjustable dumbbell, comprising:
 a dumbbell body, and   dumbbell pieces cumulatively attached to both ends of the dumbbell body, wherein:
 the dumbbell body comprises a grip rod, mounting portions disposed at both ends of the grip rod for connecting the dumbbell pieces, a first telescopic rod extending inside the dumbbell body, and a second telescopic rod extending inside the dumbbell body, 
 the first telescopic rod and the second telescopic rod are driven by the dumbbell body to extend from or retract into the dumbbell body away from each other to hang the dumbbell pieces so as to adjust a number of dumbbell pieces at the both ends of the dumbbell body, 
 the first telescopic rod and the second telescopic rod are substantially in a shape of a semicircular shaft, 
 the first telescopic rod comprises a first semicircular plane and a first diametral plane to define the shape of the semicircular shaft, 
 the first diametral plane is provided with a first sliding groove opened in a length direction of the first telescopic rod, 
 the second telescopic rod comprises a second semicircular plane and a second diametral plane to define the shape of the semicircular shaft, 
 the second diametral plane is provided with a second sliding groove opened in a length direction of the second telescopic rod, 
 a plane where the first diametral plane is located and a plane where the second diametral plane is located face each other so that the first telescopic rod and the second telescopic rod are staggeredly arranged in the dumbbell body, 
 the dumbbell body is fixedly provided with a first limiting block and a second limiting block respectively matching the first sliding groove and the second sliding groove, and 
 the first limiting block and the second limiting block are respectively slidably engaged in the first sliding groove and the second sliding groove, thereby restricting a circumferential rotation of the first telescopic rod and the second telescopic rod. 
   
     
     
         2 . The adjustable dumbbell according to  claim 1 , wherein:
 a first end of the both ends of the dumbbell body has a first exposing hole for exposing the first telescopic rod,   a second end of the both ends of the dumbbell body has a second exposing hole for exposing the second telescopic rod,   the first exposing hole and the second exposing hole are semicircular shaped, respectively matching the shape of the first telescopic rod and the shape of the second telescopic rod, and   the first limiting block and the second limiting block are respectively fixedly disposed in the first exposing hole and the second exposing hole.   
     
     
         3 . The adjustable dumbbell according to  claim 1 , wherein:
 the first telescopic rod further comprises a first sliding block disposed on the first diametral plane,   the second telescopic rod further comprises a second sliding block disposed on the second diametral plane, and   the first sliding block is slidably connected in the second sliding groove and the second sliding block is slidably connected in the first sliding groove so that the first telescopic rod and the second telescopic rod are slidably connected.   
     
     
         4 . The adjustable dumbbell according to  claim 3 , wherein:
 the first sliding groove has a first end,   the second sliding groove has a second end, and   when the first telescopic rod and the second telescopic rod are extended away from each other, the first sliding block and the second sliding block are configured to abut the second end and the first end, respectively, thereby inhibiting the first telescopic rod and the second telescopic rod from disengaging from each other.   
     
     
         5 . The adjustable dumbbell according to  claim 1 , wherein:
 one end of the first telescopic rod and one end of the second telescopic rod, pointing to an outside of the dumbbell body, each has a radially extending hooking portion, and   when the first telescopic rod and the second telescopic rod are retracted, the radially extending hooking portion is configured to be hooked on end faces of the both ends of the dumbbell body, thereby inhibiting the first telescopic rod and the second telescopic rod from retracting into the dumbbell body.   
     
     
         6 . The adjustable dumbbell according to  claim 5 , wherein the radially extending hooking portion complements the one end of the first telescopic rod and the one end of the second telescopic rod pointing to the outside of the dumbbell body to define a circular shape. 
     
     
         7 . The adjustable dumbbell according to  claim 1 , wherein the first telescopic rod and the second telescopic rod are connected to the dumbbell body by a screw pair with opposite rotation directions so that, by rotating the dumbbell body, the first telescopic rod and the second telescopic rod are driven to extend from or retract into the dumbbell body away from each other. 
     
     
         8 . The adjustable dumbbell according to  claim 7 , wherein:
 the first semicircular plane and the second semicircular plane are protrudingly provided with a first thread and a second thread with opposite rotation directions, respectively, and   the dumbbell body is provided with a first helical groove and a second helical groove that are matingly connected with the first thread and the second thread, respectively.   
     
     
         9 . The adjustable dumbbell according to  claim 1 , wherein an end of the first telescopic rod and an end of the second telescopic rod pointing to an outside of the dumbbell body has a diameter enlarged portion with an enlarged diameter. 
     
     
         10 . The adjustable dumbbell according to  claim 1 , wherein:
 end faces of both sides of the dumbbell pieces are provided with 180° symmetrically disposed clamping blocks and clamping grooves,   adjacent dumbbell pieces of the dumbbell pieces are cumulatively stacked at the both ends of the dumbbell body through snap fitting of the clamping blocks and the clamping grooves, and   a connecting line of centers of each group of the 180° symmetrically disposed clamping blocks and clamping grooves is in a plane where the first diametral plane or the second diametral plane is located.