|
1. A dumbbell apparatus which allows simple and accurate selection of a desired number of weight plates, the apparatus comprising: a handle member; a base member for positioning an equal number of weight plates on either side of said handle member, at least one handle bracket; two adjusting spline members oppositely disposed, said weight plates being further adapted to receive a full circumference portion of each said adjusting spline member which extends out from said handle member and passes through an arced slot of each of said weight plates; each said adjusting spline member comprising a bulging portion along the full circumference portion of the adjusting spline member, an interior cutaway portion configured with meshed teeth, and an interior threaded portion, said meshed teeth of the interior cutaway portion is configured to receive teeth of a threaded positioning gear; said threaded positioning gear being mounted within and near a center of said handle member, said handle member being adapted to snugly and oppositely house said interior cutaway portion of said adjusting spline members so as to keep said interior cutaway portion of one of said adjusting spline members in mechanical communication with the other interior cutaway portion of the other adjusting spline member through said threaded positioning gear; the bulging portion of each said full circumference portion of each said adjusting spline member being adapted to snugly fit through the arced slot of each said weight plate as it is cradled by said base member; an adjusting means comprising an adjusting plate mounted on one end of said handle member, the adjusting plate comprising a series of adjusting holes positioned along a length of the adjusting plate which are separated by equal distances and joined by a narrow channel of sufficient width to permit a positioning pin to slide back and forth through said narrow channel through each said adjusting holes from one end to another; said positioning pin is formed as a clevis pin with a through hole at one end, to be received by a receiving hole of one of said two adjusting spline members, and configured at an opposite end with a spring loaded cap which is adapted to fit snugly into a desired adjusting hole, each said adjusting hole being separated by a distance wherein the movement of the two adjusting spline members together, transmitted through the threaded positioning gear, causes the bulging portion of each full circumference of each said adjusting spline member to either slide into or out of the arced slot of said weight plates on each side of said handle member, and further including a cross-pin passing in the one of said two adjusting spline members and the through hole in the clevis pin, to keep the positioning pin firmly secured to the spline member.
|
