Disclosed herein is a modular kettle-bell shaped dumbbell having separate, equally weighted dumbbell portions that may optionally be used separately or may be temporarily joined together to form a single kettle-bell shaped dumbbell of twice the weight of the separate, equally weighted dumbbell portions. Each of the separate dumbbell portions may include one part of a two-piece connection system configured to temporarily lock the separate dumbbell portions to one another, with such connectors being configured such that upon achieving a fully engaged locking connection, the exteriors of each body portion of the first dumbbell portion and the second dumbbell portion together form a generally spherical main body portion and an upwardly extending handle having a generally circular cross-section throughout its length.

Disclosed herein is a modular kettle-bell shaped dumbbell having separate, equally weighted dumbbell portions that may optionally be used separately or may be temporarily joined together to form a single kettle-bell shaped dumbbell of twice the weight of the separate, equally weighted dumbbell portions. Each of the separate dumbbell portions may include one part of a two-piece connection system configured to temporarily lock the separate dumbbell portions to one another, with such connectors being configured such that upon achieving a fully engaged locking connection, the exteriors of each body portion of the first dumbbell portion and the second dumbbell portion together form a generally spherical main body portion and an upwardly extending handle having a generally circular cross-section throughout its length.

The present invention relates to a system (S) for monitoring the weight adjustment of a dumbbell, which can be used by a user to perform a gymnastic exercise, comprising: a dumbbell (2), provided with a handle (21), having an axial development along an axis (R), able to rotate around said axis (R), clockwise and counterclockwise, and provided with a first end (211) and a second end (212), a first plurality of weights (P1), wherein each weight can be individually coupled to said first end (211), when said handle (21) rotates in one direction, and decoupled from said first end (211), when said handle (21) rotates in the opposite direction, a second plurality of weights (P2), wherein each weight can be individually coupled to said second end (212), when said handle (21) rotates in one direction, and decoupled from said second end (212), when said handle (21) rotates in the opposite direction, wherein said system (S) is characterised in that it comprises an element provided with a plurality of reflective portions (321.sub.a, b, . . . , n), in that it comprises at least one detection device (5) able to detect data coming from at least one reflective portion (321.sub.k) and able to send said data, and in that it comprises a logic control unit (U) able to receive said data sent by said at least one detection device (5) and to associate to said data a weight of said first (P1) and second (P2) plurality of weights. The present invention also relates to the method for operating such system.

The present invention relates to a system (S) for monitoring the weight adjustment of a dumbbell, which can be used by a user to perform a gymnastic exercise, comprising: a dumbbell (2), provided with a handle (21), having an axial development along an axis (R), able to rotate around said axis (R), clockwise and counterclockwise, and provided with a first end (211) and a second end (212), a first plurality of weights (P1), wherein each weight can be individually coupled to said first end (211), when said handle (21) rotates in one direction, and decoupled from said first end (211), when said handle (21) rotates in the opposite direction, a second plurality of weights (P2), wherein each weight can be individually coupled to said second end (212), when said handle (21) rotates in one direction, and decoupled from said second end (212), when said handle (21) rotates in the opposite direction, wherein said system (S) is characterised in that it comprises an element provided with a plurality of reflective portions (321.sub.a, b, . . . , n), in that it comprises at least one detection device (5) able to detect data coming from at least one reflective portion (321.sub.k) and able to send said data, and in that it comprises a logic control unit (U) able to receive said data sent by said at least one detection device (5) and to associate to said data a weight of said first (P1) and second (P2) plurality of weights. The present invention also relates to the method for operating such system.

An adjustable weight lifting device (21) includes a tube (31), a pin (33) movably disposed inside the tube (31), the pin (33) comprising an external thread (35), and one or more driving knobs (51) extending radially inward relative to an inner wall of the tube (31) and engaging with the external thread. The external thread comprises at least one portion having a first helix angle and at least one portion having a second helix angle, the second helix angle being smaller than the first helix angle.

An adjustable weight lifting device (21) includes a tube (31), a pin (33) movably disposed inside the tube (31), the pin (33) comprising an external thread (35), and one or more driving knobs (51) extending radially inward relative to an inner wall of the tube (31) and engaging with the external thread. The external thread comprises at least one portion having a first helix angle and at least one portion having a second helix angle, the second helix angle being smaller than the first helix angle.

The present invention relates to a novel fitness weight device designed to allow users to customize dumbbell weights by filling the air chambers with air. The device comprises a dumbbell-styled weight with an inflatable air chamber. The devices can be inflated via a push button. Users can inflate the dumbbell devices to a desired weight for customized workouts. Once finished, the user can activate the air release valve to compact or retract the dumbbell for storage.

The present invention relates to a novel fitness weight device designed to allow users to customize dumbbell weights by filling the air chambers with air. The device comprises a dumbbell-styled weight with an inflatable air chamber. The devices can be inflated via a push button. Users can inflate the dumbbell devices to a desired weight for customized workouts. Once finished, the user can activate the air release valve to compact or retract the dumbbell for storage.

A set of dumbbells comprises a plurality of dumbbells of different weights with the dumbbells having a common length. A plurality of adder weights is provided with each adder weight having a cavity that is sized to receive the common length of any one of the dumbbells. Any one of the dumbbells is dropped down into the cavity of any one of the adder weights. A slide retainer is then slid into a slideway on the any one adder weight to overlie the dumbbell and secure the dumbbell to the any one adder weight. The slide retainer has a window therein to allow a user to reach through the slide retainer and grip a hand grip of the dumbbell.

A set of dumbbells comprises a plurality of dumbbells of different weights with the dumbbells having a common length. A plurality of adder weights is provided with each adder weight having a cavity that is sized to receive the common length of any one of the dumbbells. Any one of the dumbbells is dropped down into the cavity of any one of the adder weights. A slide retainer is then slid into a slideway on the any one adder weight to overlie the dumbbell and secure the dumbbell to the any one adder weight. The slide retainer has a window therein to allow a user to reach through the slide retainer and grip a hand grip of the dumbbell.