Weight-training apparatus having selectable weight plates

An adjustable weight-training apparatus, comprising:

• a plurality of weight plates, each of said weight plates having a central hole and a slot, said slot extending generally vertically upwardly from said central hole to a periphery of said weight plate, the width of said slot being smaller than the diameter of said central hole, and the intersection of one side of said slot and said central hole forming a protrusion, said weight-training apparatus having longitudinally opposing ends portions, each of said end portions having longitudinally outer and inner groups of said weight plates;
• a rotatable bar comprising an inner control shaft and an outer control shaft, said inner control shaft configured to rotate within and independently of said outer control shaft and said rotatable bar configured to rotate within said central holes;
• said inner control shaft having a first plurality of longitudinally spaced lobes, said inner control shaft being rotatable to position selected ones of said first plurality of lobes in engagement with said protrusions of said central holes of selected weight plates of said outer groups of weight plates, to secure said selected weight plates of said outer groups to said inner control shaft;
• and
• said outer control shaft having a second plurality of longitudinally spaced lobes, said outer control shaft being rotatable to position selected ones of said second plurality of lobes in engagement with said protrusions of said central holes of selected weight plates of said inner groups of weight plates, to secure said selected weight plates of said inner groups to said outer control shaft;
• and
• a non-rotatable sleeve extending through said central holes, said rotatable bar being configured to rotate within said sleeve, said sleeve including a pair of channels positioned at opposing ends thereof and configured to expose said first and second plurality of longitudinally spaced lobes.

In a weight-training apparatus of the type having a plurality of longitudinally spaced weight plates arranged in groups adjacent the opposite end portions of the apparatus, the weight plates each having a central hole and a slot extending generally vertically upwardly from said central hole to a periphery of said weight plate, the width of said slot being smaller than the diameter of said central hole, and the intersection of one side of said slot and said central hole forming a protrusion, and a rotatable bar passing through said central holes and provided with a plurality of longitudinally spaced lobes selectively engageable with selected ones of said protrusions upon rotation of said bar, the improved method of selecting weight plates for securement to said bar comprising:

• forming said bar of coaxial and independently rotatable inner and outer control shafts, said inner control shaft being rotatable within said outer control shaft,
• rotating said inner control shaft to one or more predetermined positions to secure selected weight plates from a first sub-set of weight plates located adjacent the opposite end portions of the apparatus to said inner control shaft, and rotating said inner control shaft to other predetermined positions to unlock selected weights from said inner control shaft;
• rotating said outer control shaft to one or more predetermined positions to secure selected weight plates from a second sub-set of weight plates located adjacent the opposite end portions of the apparatus to said outer control shaft, and rotating said outer control shaft to other predetermined positions to unlock selected weights from said outer control shaft, said first and second sub-sets of weight plates being mutually exclusive.