Abstract: The present invention relates to a dumbbell and especially relates to an improvement on an assembly mode of a grip rod and flanges at both ends thereof in the dumbbell. The present invention axially positions the grip rod and the flange by the assembly of the first assembly groove in an L shape on the grip rod and the positioning block on the flange, then circumferentially positions the grip rod and the flange by plugging a positioning pin in the first assembly groove of the grip rod and the second assembly groove of the flange simultaneously, in cooperation with the shaft-hole fitting of the grip rod and the flange themselves, thereby implementing screw-free installation of the grip rod and the flange, simple manufacturing, a low cost and a high installation efficiency.

Abstract: The present invention relates to an adjustable dumbbell, which includes a rotatably disposed grip rod and a locking element, wherein a locking portion is disposed at both ends of the grip rod, the locking element includes a base, a movable pin and a compression spring, the movable pin is slidably disposed in the base, the base is provided with a first spring sleeve column, the movable pin is provided with a second spring sleeve column, and both ends of the compression spring are respectively sleeved and positioned on the first spring sleeve column and the second spring sleeve column. In the present invention, the base and the movable pin are both provided with the spring sleeve column, which is not only convenient to mount and position the compression spring during assembly, but also can prevent the compression spring from falling out due to the shaking of dumbbells in use.

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.

Abstract: The present invention relates to a fast-adjusting dumbbell, comprising a dumbbell body and dumbbell pieces cumulatively attached to both ends of the dumbbell body. The dumbbell body includes a grip rod, a planetary gear system, and a telescopic rod. The grip rod is rotated and drives the planetary gear system to realize the expansion and contraction of the telescopic rod, thereby adjusting the number of dumbbell pieces, which is convenient to operate and easy to implement. Both ends of the grip rod are assembled with flange driving members, the planetary gear system includes an outer casing, through the installation mode that the flange driving member is engaged with the planetary gear system, the planetary gear mechanism is disposed enclosedly, and a load-bearing iron ring is also disposed in the planetary gear system to play a load-bearing and limiting effect on the planetary carrier.