Weight selection methods and apparatus

[0001] This is a continuation-in-part of U.S. patent application Ser. No. 12/214,322, filed Jun. 17, 2008 now U.S. Pat. No. 7,648,448, which in turn, is a continuation of U.S. patent application Ser. No. 11/652,950, filed Jan. 12, 2007 (U.S. Pat. No. 7,387,597), which in turn, discloses subject matter entitled to the filing date of U.S. Provisional Application No. 60/759,998, filed Jan. 17, 2006.

[0002] The present invention relates to exercise equipment and in a preferred application, to methods and apparatus for adjusting weight resistance to exercise activity.

[0003] Past efforts have led to various inventions directed toward adjustable weight exercise devices. Some examples of such efforts in the field of free weights are disclosed in U.S. Pat. No. 3,771,785 to Speyer; U.S. Pat. No. 4,529,198 to Hettick, Jr.; U.S. Pat. No. 4,822,034 to Shields; U.S. Pat. No. 4,284,463 to Shields; U.S. Pat. No. 5,637,064 to Olson et al.; U.S. Pat. No. 5,769,762 to Towley, III et al.; U.S. Pat. No. 5,839,997 to Roth et al.; U.S. Pat. No. 6,033,350 to Krull; U.S. Pat. No. 6,099,442 to Krull; U.S. Pat. No. 6,322,481 to Krull; and U.S. Pat. No. 6,855,097 to Krull. Despite these advances in the field of weight lifting equipment, room for continued improvement remains with respect to selecting different combinations of weight for exercise purposes.

[0004] The present invention is directed toward methods and apparatus involving the movement of mass subject to gravitational force. In a preferred application, the present invention allows a person to adjust weight resistance by securing desired amounts of mass to a handlebar or other weight lifting member.

[0005] A first embodiment of the present invention may be described in terms of an exercise dumbbell having a handle member that includes a first weight supporting section, a second weight supporting section, and a handle extending therebetween and defining a longitudinal axis. First weights are configured and arranged to occupy the first weight supporting section, and second weights are configured and arranged to occupy the second weight supporting section. A weight selector is movably mounted on the handle member for movement parallel to the longitudinal axis to selectively engage and disengage one of the first weights. A knob is rotatably mounted on the handle member for rotation about an axis extending parallel to the longitudinal axis, and the weight selector is preferably compressed between the knob and a spring. The knob is configured to alternatively push the weight selector in a first direction relative to the handle member, and accommodate movement of the weight selector in an opposite, second direction relative to the handle member, as a function of the knob's orientation relative to the handle member. The resulting change in position of the weight selector alternatively engages and disengages the associated first weight. A similar arrangement is preferably provided on the opposite end of the handle member to selectively engage and disengage one of the second weights.

[0006] On an alternative embodiment, rotation of the knob to a first orientation moves the selector a first distance to engage a first weight plate, and rotation of the knob to a second orientation moves the selector a second distance to engage both the first weight plate and a second weight plate.

[0007] Another embodiment of the present invention may be described in terms of an exercise kettlebell having a handle member that includes a weight supporting section, a handle disposed above the weight supporting section, a weight selector, and a knob. Weights are configured and arranged to occupy the weight supporting section, and to be selectively engaged and disengaged as described above with reference to the dumbbell embodiment.

[0008] Yet another aspect of the present invention is to make common parts for use on both a selectorized dumbbell and a selectorized kettlebell. Many features and advantages of the present invention will become apparent from the detailed description that follows.

[0031] FIG. 1 shows an exercise dumbbell 100 constructed according to the principles of the present invention. In many respects, the dumbbell 100 is functionally similar to the dumbbell disclosed in U.S. Pat. No. 5,839,997 to Roth et al., which is incorporated herein by reference to the extent it may help facilitate understanding of the present invention. Like the Roth dumbbell, the dumbbell 100 includes a weight lifting member or handle member 110, a plurality of weight plates 181 and 191 that are selectively secured to the handle member 110, and a base or cradle (not shown) that supports the other components when not in use. In fact, the only functional differences between the Roth dumbbell and the dumbbell 100 are (1) the separation of the selector shaft into two discrete pieces, one at each end of the dumbbell; and (2) the selective engagement of additional weights 182 and 192.

[0032] Generally speaking, the handle member 110 includes an intermediate handle or hand grip 114, and first and second weight supporting sections 118 and 119 disposed at opposite ends of the handle 114. The selector shafts (one of which is designated as 112 in FIG. 2) extend through the respective weight supporting sections 118 and 119, and are rigidly secured to respective knobs 108 and 109. On the dumbbell 100, the shafts have cammed segments that are configured to sequentially engage respective weight plates 181 and 191 upon each eighty degrees of rotation in a first direction, and to release respective weight plates 181 and 191 upon each eighty degrees of rotation in an opposite, second direction.

[0033] Among other things, FIG. 2 shows a weight selector 160 that is movably mounted in the weight supporting section 118 for movement parallel to a longitudinal axis defined by the handle 114. As shown in FIG. 3, the weight selector 160 includes a relatively wider portion that includes laterally extending flanges 162 and 164, and a relatively narrower portion 165 that does not have any such flanges. The narrower portion terminates in a distal end 168 that may be described as pointed or triangular. A rib 167 projects upward from the wider portion and cooperates with a channel (not shown) in the weight supporting section 118 to limit movement of the weight selector to a desired path of motion (parallel to the longitudinal axis of the handle 114). Also, a tab 166 projects outward from an end of the wider portion, opposite the pointed end 168, to support one end of a helical coil spring 116 (shown in FIG. 2). The spring 116 is compressed between the weight selector 160 and the inward end plate (disposed adjacent the handle 114) on the weight supporting section 118.

[0034] As shown in FIG. 2, the weight selector 160 has an overall width that is less than the width of the upwardly opening slots in the weight plates 181, thereby accommodating upward movement of the weight selector 160 relative thereto. Also, the narrower portion of the weight selector 160 is narrower than the width of the upwardly opening slot in the weight plate 182, but the wider portion of the weight selector 160 is wider than the width of the upwardly opening slot in the weight plate 182, so lateral notches are provided in the weight plate 182 to accommodate the flanges 162 and 164. The weight selector 160 is movable between a first position, wherein the narrow portion 165 occupies the slot in the weight plate 182 and thus, the weight selector 160 is free to move upward relative to the weight plate 182, and a second position, wherein the flanges 162 and 164 occupy the notches in the weight plate 182 and thus, the weight plate 182 is constrained to move upward together with the weight selector 160.

[0035] FIG. 4 shows the knob 108 from the same perspective as FIG. 2, but with the other components removed. A cavity 102 is centrally located in the knob 108 to facilitate keyed mounting of the knob 108 onto the bar 112. Also, a series of circumferentially spaced recesses are provided in the knob 108 to define a contoured bearing surface that aligns with the distal end 168 of the weight selector 160. The recesses include relatively long and penetrating inclined surfaces or ramps 103 (with small flats 104 disposed between the relatively deeper ends thereof), and relatively short and shallow inclined surfaces or ramps 105 (with flats 106 disposed between the relatively deeper ends thereof). The flats 104 and 106 are disposed at forty degree intervals apart from one another.

[0036] When a flat 106 is rotated into alignment with the weight selector 160, the knob 108 pushes the weight selector 160 into the first position described above (with the narrow portion 165 occupying the slot in the weight plate 182). When a flat 104 is rotated into alignment with the weight selector 160, force exerted by the spring 116 pushes the weight selector 160 into the second position described above (with the flanges 162 and 164 occupying the notches in the weight plate 182).

[0037] In FIG. 4, the letter A indicates the location on the knob 108 for the lowermost weight setting. When this sector of the knob 108 is rotated into alignment with the weight selector 160, none of the weights 181 or 182 is engaged to be lifted together with the handle member 110. The letter B indicates the location on the knob 108 for the second lowest weight setting. When this sector of the knob 108 is rotated into alignment with the weight selector 160, the weight 182 is engaged to be lifted (and the weights 181 remain disengaged). The letter C indicates the location on the knob 108 for the third lowest weight setting. When this sector of the knob 108 is rotated into alignment with the weight selector 160, the weight 182 is disengaged, while one of the weights 181 is engaged to be lifted together with the handle member 110 (because a knuckle on the shaft 112 rotates into a laterally extending notch in the associated weight 181). The letter D indicates the location on the knob 108 for the fourth lowest weight setting. When this sector of the knob 108 is rotated into alignment with the weight selector 160, the engaged weight 181 remains engaged, and the weight 182 is re-engaged to be lifted together with the handle member 110. The process continues as two more of the weights 181 are successively engaged, and the weight 182 is alternately engaged and disengaged.

[0038] With each of the weights 181 made to weigh 5 pounds, and the weight 182 made to weigh 2.5 pounds, a total of 17.5 pounds may be added to the associated end of the handle member 110 in increments of 2.5 pounds. With a similar arrangement at the opposite end of the handle member 110, weight may be added to the handle member 110 in balanced increments of 5 pounds (and out of balance increments of 2.5 pounds). With the handle member 110 made to weigh 5 pounds, the weight of the dumbbell 100 is adjustable between 5 and 40 pounds. On an alternative embodiment, the two selector shafts 112 are rigidly interconnected to form a single integral shaft (that extends through the handle member). On this embodiment, rotation of either knob 108 or 109 adjusts both end of the dumbbell (and the weight is adjustable only in balanced 5 pound increments).

[0039] FIG. 5 shows components of an alternative embodiment exercise dumbbell constructed according to the principles of the present invention. The depicted components are shown with most of the handle assembly components removed for ease of illustration (the missing components cooperate to maintain the depicted parts in the relative positions shown in FIG. 5). At each end of this dumbbell, there are three discrete selectors 370, 380, and 390 that operate (in a manner similar to the selectors 160 on the dumbbell 100) to selectively engage three discrete weight plates 270, 280, and 290, respectively. Bolts 212 extend through longitudinally extending slots 372, 382, and 392 in respective selectors 370, 380, and 390, and are threaded into a main bar 212 to slidably connect the selectors 370, 380, and 390 to the bar 212 for sliding parallel to a longitudinal axis defined by the bar 212.

[0040] A knob 309 is rotatably mounted on a suitably configured end of the bar 212. In this regard, the end of the bar 212 is rounded to fit into a central bore 312 in the knob 309, and a bolt (not shown) is inserted through a central hole 310 in the knob 309 and threaded into the bar 212. The bolt is configured to tighten firmly in place relative to the bar 212 with just enough of a gap defined between the bar 212 and the head of the bolt to accommodate easy rotation of the knob 309 relative thereto. A stand-off section on the bolt and/or thrust washers may be used to ensure smooth rotation of the knob 309.

[0041] As shown in FIG. 6, the inward facing side of the knob 309 is provided with three concentrically aligned, circumferential bearing surfaces. The radially outermost bearing surface is comprised of small, relatively shallow depressions 316, relatively larger and deeper depressions 317, and flats disposed therebetween. The centers of the depressions 316 and 317 associated with designated knob sectors S5-S20 are disposed at forty degree angles relative one another; the centers of the depressions 316 and 317 associated with designated knob sectors S25-S40 are similarly disposed at forty degree angles relative to one another; and the centers of the depressions 316 associated with designated knob sectors S5 and S25 are disposed at an angle of one hundred eighty degrees relative to one another.

[0042] The radially intermediate bearing surface is comprised of relatively longer depressions 318 (which are comparable in depth to the depressions 317) and relatively longer flats disposed therebetween. The center of the depression 318 associated with designated knob sectors S5-S10 is disposed twenty degrees counter-clockwise relative to the center of the depression 316 associated with the knob sector S5; and the centers of the two depressions 318 are disposed at an angle of one hundred eighty degrees relative to one another. The radially innermost bearing surface is comprised of a relatively longer and deeper depression 319 and a relatively longer, diametrically opposed flat. The center of the depression 319 is disposed sixty degrees counter-clockwise relative to the center of the depression 316 associated with the knob sector S5.

[0043] FIGS. 7a-7b show the uppermost weight selector 370 relative to the weight plates 370, 380, and 390. As noted above, a slot 372 extends through the selector 370 to accommodate bolts 202, and to accommodate travel of the selector 370 relative thereto. The selector 370 has a first end or tip 373 that may be described as pointed or triangular, and an opposite, second end that bears against one end of a helical coil spring 327. An opposite end of the spring 327 bears against an inner end plate (not shown) on the handle assembly. Also, a tab 377 projects laterally outward from the selector 370.

[0044] The tip 373 of the selector 370 is configured and arranged to align with and bear against the radially outermost bearing surface on the knob 309. As shown in FIG. 5, the tip 373 has an arcuate profile that is centered about the longitudinal axis of the bar 212 (and that matches the curvature of the depressions 317). FIG. 7a shows the position occupied by the selector 370 when the tip 373 occupies any one of the small depressions 316 in the knob 309 (disposed in sectors S5, S15, S25, and S35). When the selector 370 occupies this position, the tab 377 is clear of the weight plate 270 and free to move upward relative thereto. FIG. 7a also shows that the weight plate 280 is configured to accommodate the tab 377 without being engaged for upward movement together therewith.

[0045] FIG. 7b shows the position occupied by the selector 370 when the tip 373 occupies any one of the larger depressions 317 in the knob 309 (disposed in sectors S10, S20, S30, and S40). When the selector 370 occupies this position, the tab 377 occupies a laterally opening notch (see FIG. 5) in the weight plate 270, thereby constraining the weight plate 270 to move upward.

[0046] The spring 327 biases the selector 370 against the knob 309 and into a respective depression 316 or 317 (when aligned relative thereto). The depressions 316 and 317 are relatively deep in the middle and relatively shallow at the ends, thereby encouraging the tip 373 to center itself within a respective depression 316 or 317, and also providing angled bearing surfaces to urge the tip 373 out of the respective depression 316 or 317 in response to rotation of the knob 309 in either direction.

[0047] FIGS. 8a-8b show the intermediate weight selector 380 relative to the weight plates 370, 380, and 390. As noted above, a slot 382 extends through the selector 380 to accommodate bolts 202, and to accommodate travel of the selector 380 relative thereto. The selector 380 has a first end or tip 383 that may be described as pointed or triangular, and an opposite, second end that bears against one end of a helical coil spring 328. An opposite end of the spring 328 bears against an inner end plate (not shown) on the handle assembly. Also, a tab 388 projects laterally outward from the selector 380.

[0048] The tip 383 of the selector 380 is configured and arranged to align with and bear against the radially intermediate bearing surface on the knob 309. As shown in FIG. 5, the tip 383 has an arcuate profile that is centered about the longitudinal axis of the bar 212 (and that matches the curvature of the depressions 318). FIG. 8a shows the position occupied by the selector 380 when the tip 383 occupies either of the depressions 318 in the knob 309 (disposed in sectors S5-S10 and S25-S30). When the selector 380 occupies this position, the tab 388 is clear of the weight plate 280 and free to move upward relative thereto. FIG. 8a also shows that the weight plate 270 is configured to accommodate the tab 388 without being engaged for upward movement together therewith.

[0049] FIG. 8b shows the position occupied by the selector 380 when the tip 383 bears against any flat portion of the knob 309 (disposed in sectors S15-S20 and S35-S40). When the selector 380 occupies this position, the tab 388 occupies a laterally opening notch (see FIG. 5) in the weight plate 280, thereby constraining the weight plate 280 to move upward.

[0050] The spring 328 biases the selector 380 against the knob 309 and into a respective depression 318 (when aligned relative thereto). The depressions 318 are relatively deep in the middle and relatively shallow at the ends, thereby providing angled bearing surfaces to urge the tip 383 out of the respective depression 319 in response to rotation of the knob 309 in either direction. The depressions 318 are preferably flat in the middle, so the selector 380 does not move significantly during movement between sectors S5 and S10, nor during movement between sectors S25 and S30.

[0051] FIGS. 9a-9b show the lowermost weight selector 390 relative to the weight plates 370, 380, and 390. As noted above, a slot 392 extends through the selector 390 to accommodate bolts 202, and to accommodate travel of the selector 390 relative thereto. The selector 390 has a first end or tip 393 that may be described as pointed or triangular, and an opposite, second end that bears against one end of a helical coil spring 329. An opposite end of the spring 329 bears against an inner end plate (not shown) on the handle assembly. Also, tabs 396 and 399 project laterally outward from respective sides of the selector 390.

[0052] The tip 393 of the selector 390 is configured and arranged to align with and bear against the radially inwardmost bearing surface on the knob 309. As shown in FIG. 5, the tip 393 has an arcuate profile that is centered about the longitudinal axis of the bar 212 (and that matches the curvature of the depression 319). FIG. 9a shows the position occupied by the selector 390 when the tip 393 occupies the depression 319 in the knob 309 (disposed in sectors S5-S20). When the selector 390 occupies this position, the tabs 396 and 399 are clear of the weight plate 290 and free to move upward relative thereto. FIG. 9a also shows that the weight plate 280 is configured to accommodate the tab 396 without being engaged for upward movement together therewith (and that a portion of the weight plate 290 is configured to accommodate the shorter tab 399 without being engaged for upward movement).

[0053] FIG. 9b shows the position occupied by the selector 390 when the tip 393 bears against any flat portion of the knob 309 (disposed in sectors S25-S40). When the selector 390 occupies this position, the tabs 396 and 399 occupy respective, laterally opening notches in the weight plate 290 (similar in cross-section to the notches shown in the weight plates 270 and 280), thereby constraining the weight plate 290 to move upward.

[0054] The spring 329 biases the selector 390 against the knob 309 and into the depression 319 (when aligned relative thereto). The depression 319 is relatively deep in the middle and relatively shallow at the ends, thereby providing angled bearing surfaces to urge the tip 393 out of the respective depression 319 in response to rotation of the knob 309 in either direction. The depression 319 is relatively deeper than the depressions 317 and 318 to encourage additional longitudinal travel of the selector 390, and it is preferably flat in the middle, so the selector 390 does not move significantly during movement among sectors S5-S20.

[0055] A respective knob 309 at each end of the dumbbell is rotated relative to the bar 212 to place the contoured bearing surfaces in alignment with respective selector tips 373, 383, and 393. When the S5 sectors are positioned at 12:00 relative to the bar 212, the selectors 370, 380, and 390 are held in the positions shown in FIGS. 7a, 8a, and 9a, respectively. With the handle assembly made to weigh 5 pounds, this position of the knobs 309 sets the current dumbbell weight at 5 pounds (because none of the weight plates 270, 280, and 290 are engaged for upward movement).

[0056] With two weight plates 270 of 2.5 pounds each, and the S10 sectors positioned at 12:00 relative to the bar 212, the current dumbbell weight becomes 10 pounds (because the weight plates 270 are now engaged for upward movement together with the handle assembly). With two weight plates 280 of 5 pounds each, and the S15 sectors positioned at 12:00 relative to the bar 212, the current dumbbell weight becomes 15 pounds (because the weight plates 280 are now engaged for upward movement together with the handle assembly). With two weight plates 290 of 10 pounds each, and the S25 sectors positioned at 12:00 relative to the bar 212, the current dumbbell weight becomes 25 pounds (because the weight plates 290 are now engaged for upward movement together with the handle assembly). In all, the dumbbell is adjustable from 5 to 40 pounds in balanced increments of 5 pounds, and out-of-balance increments of 2.5 pounds. Indicia may be provided on the knobs 309 to indicate the weight of the dumbbell as a function of the orientation of the knobs 309. The two indicated amounts are preferably averaged to determine the current selected weight.

[0057] On an alternative embodiment, the main bar 212 is replaced by a main tube, and a rod is rotatably mounted inside the tube and rigidly connected to both knobs. An advantage of this arrangement is that either knob may be rotated to simultaneously adjust the weight at both ends of the dumbbell. Another advantage of this arrangement is that a single locking mechanism may be applied to the rod or either knob for purposes of preventing unintended rotation of the knobs. An example of a suitable locking mechanism is disclosed in U.S. Pat. No. 6,540,650 to Krull, which is incorporated herein by reference. On the other hand, a disadvantage of this arrangement is that the dumbbell is no longer adjustable in out-of-balance increments of 2.5 pounds.

[0058] FIG. 10 shows an alternative embodiment knob 409 that is similar to the knob 309 shown in FIG. 6, except for the configuration and arrangement of bearing surfaces the interior face of the knob 409, and the associated weight indicia (not shown) on the exterior of the knob 409. In other words, on an alternative embodiment of the present invention, the knob 409 is rotatably mounted on a suitably configured end of another bar 212. In this regard, the end of the bar 212 is rounded to fit into a central bore 412 in the knob 409, and a bolt (not shown) is inserted through a central hole 410 in the knob 409 and threaded into the bar 212. The bolt is configured to tighten firmly in place relative to the bar 212 with just enough of a gap defined between the bar 212 and the head of the bolt to accommodate easy rotation of the knob 409 relative thereto. A stand-off section on the bolt and/or thrust washers may be used to ensure smooth rotation of the knob 409.

[0059] As shown in FIG. 10, the inward facing side of the knob 409 is provided with three concentrically aligned, circumferential bearing surfaces. These bearing surfaces cooperate to define discrete weight combinations or settings W1-W12 at intervals of 30 degrees, where W12 aligns with 12:00 on a conventional analog clock. As referenced relative to a conventional analog clock, the radially outermost bearing surface is comprised of (a) small, relatively shallow depressions 416 disposed at 12:00, 3:00, 6:00, and 9:00; (b) relatively longer and deeper, two-tiered depressions 417 extending from 12:30 to 2:30, from 3:30 to 5:30, from 6:30 to 8:30, and from 9:30 to 11:30; and (c) flats disposed between these depressions. The radially intermediate bearing surface is comprised of (a) depressions 418 extending from 3:30 to 6:30, and from 9:30 to 12:30; and (b) relatively longer flats disposed between these depressions. The radially outermost bearing surface is comprised of (a) a depression 419 extending from 6:30 to 12:30; and (b) a flat extending from 12:30 to 6:30. The ends of each depression 416-419 are inclined to accommodate movement of a respective weight selector into and out of the depression.

[0060] FIGS. 11A-11C show the weight plates 290, 280, and 270 together with an additional weight plate 270B, and an alternative embodiment uppermost weight selector 470 suitable for use with the knob 409. As compared to the selector 370, the selector 470 is relatively longer, and has a relatively longer tab 477. The knob 409 is configured for use with the intermediate weight selector 380 shown in FIGS. 8A-8B, and the lowermost weight selector 390 shown in FIGS. 9A-9B. A slot 472 extends through the selector 470 to accommodate travel of the selector 470 relative to repositioned bolts 202. The selector 470 has a first end or tip 473 that may be described as pointed or triangular, and an opposite, second end that bears against one end of a helical coil spring 427. An opposite end of the spring 427 bears against an inner end plate (not shown) on the dumbbell handle member.

[0061] The tip 473 of the selector 470 is configured and arranged to align with and bear against the radially outermost bearing surface on the knob 409. As on the selector 370, the tip 473 has an arcuate profile that is centered about the longitudinal axis of the bar 212 (and that matches the curvature of the depressions 417). FIG. 7a shows the position occupied by the selector 470 when the tip 473 occupies any one of the small depressions 416 in the knob 409 (disposed in sectors W3, W6, W9, and W12). When the selector 470 occupies this position, the tab 477 is clear of both weight plates 270 and 270B, and free to move upward relative thereto. FIG. 11A also shows that the weight plate 280 is configured to accommodate the relatively larger tab 477 without being engaged for upward movement together therewith.

[0062] FIG. 11B shows the position occupied by the selector 470 when the tip 473 occupies the first, relatively shallower level of any one of the larger depressions 417 in the knob 409 (disposed in sectors W2, W5, W8, and W11). When the selector 470 occupies this position, the tab 477 occupies a laterally opening notch (see FIG. 5) in the weight plate 270, thereby constraining the weight plate 270 to move upward.

[0063] FIG. 11C shows the position occupied by the selector 470 when the tip 473 occupies the second, relatively deeper level of any one of the larger depressions 417 in the knob 409 (disposed in sectors W1, W4, W7, and W10). When the selector 470 occupies this position, the tab 477 occupies a laterally opening notches (see FIG. 5) in both weight plates 270 and 270B, thereby constraining both weight plates 270 and 270B to move upward.

[0064] The spring 427 biases the selector 470 against the knob 409 and into a respective depression 416 or 417 (when aligned relative thereto). Each level of each depression 416 and 417 is relatively deep in the middle and relatively shallow at the ends, thereby encouraging the tip 473 to center itself therein, and also providing angled bearing surfaces to urge the tip 473 out of the respective depression 416 or 417 in response to rotation of the knob 409 in either direction.

[0065] Using the selector 470 to engage two weight plates 270 and 270B allows for a wider range of weight selections (12 instead of 8). In this regard, the weight plates 270 and 270B may be configured to weigh 2.5 pounds each, in which case the weight plates 280 may be configured to weigh 7.5 pounds each, and the weight plates 290 may be configured to weigh up to 15 pounds each. Under these circumstances, the resulting alternative embodiment dumbbell may be adjusted from 5 to 60 pounds in balanced increments of 5 pounds and out-of-balance increments of 2.5 pounds.

[0066] The subject invention has been described with reference to particular embodiments with an emphasis on the novel aspects of the subject invention. Among other things, various arrangements may be used to maintain proper alignment of the weight plates both on the handle member and when not in use. Some such arrangements are disclosed in the patents identified in the Background of the Invention, which are incorporated herein by reference to the extent they may help facilitate understanding of the subject invention. Persons skilled in the art will also recognize that features of the various embodiments may be mixed and matched as deemed necessary and/or desirable.

[0067] FIG. 12 shows one possible arrangement for supporting dumbbell weight plates 570, 580, and 590 apart from a dumbbell handle member 510. In this regard, FIG. 12 shows an alternative embodiment dumbbell system constructed according to the principles of the present invention, and including both an adjustable weight dumbbell 500 and a weight supporting base 550. Except as noted below, the dumbbell 500 is operationally similar to the dumbbell shown in and described with reference to FIG. 5. Except for size and peripheral shape, the weight plates 570 are similar to the weight plates 270; the weight plates 580 are similar to the weight plates 280; and the weight plates 590 are similar to the weight plates 290. The weight plates 570, 580, and 590 are twice as heavy as their counterparts 270, 280, and 290, and the handle member 510 is configured to weigh ten pounds apart from the weight plates 570, 580, and 590. As a result, the dumbbell 500 is adjustable from 10 to 80 pounds in balance increments of 10 pounds and out-of-balance increments of 5 pounds.

[0068] The base 550 includes a first weight supporting section 555, an identical second weight supporting section 555, and an intermediate support 557 rigidly secured therebetween. The support 557 is configured and arranged to maintain the sections 555 at a desired distance apart from one another. A shown in FIG. 12, each section 555 is configured and arranged to maintain respective weight plates 570, 580, and 590 in desired locations relative to one another and relative to respective weight supports at respective ends of the dumbbell handle 514. The support 557 is preferably extruded aluminum, and the sections 555 are preferably injection molded plastic. The support 557 is preferably secured to each section 555 using fasteners (not shown), such as screws, for example. An advantage of this arrangement is that a relatively smaller tool may be used to make the sections 555, as compared to the overall size of the base 550. Another advantage of this arrangement is that one of the sections 555 may be used by itself to support kettlebell weight plates as described below with reference to FIGS. 13-14.

[0069] Another distinction of the dumbbell 500 is the provision of a safety mechanism to discourage unintentional changes in which weights are secured to the dumbbell 500. In this regard, a respective safety latch 549 is slidably mounted and spring-biased on each weight supporting section (similar to and above the locations of the selectors 370, 380, and 390 shown in FIG. 5). A distal end 548 of each latch 549 is configured to protrude through an aligned opening 508 in a respective knob 509 whenever the knob is rotated to a desired weight engaging orientation. As with the selectors 370, 380, and 390, a spring (not shown) biases the latch end 548 toward the knob 509 and into a respective hole 508. As a result, a user must move the latch 549 toward the handle 514 to free the knob 509 for rotation relative thereto.

[0070] FIGS. 13-14 show an exercise kettlebell system constructed according to the principles of the present invention, and including an adjustable weight kettlebell 600 and a weight supporting base 555. The kettlebell system using many of the same components as the dumbbell system shown in FIG. 12, and thus, only the differences between the two will be discussed in detail below. In this regard, the present invention may be described in terms of a method of making exercise equipment, including the steps of making a plurality of identical weight plates 570; making a selectorized dumbbell 500 using a first subset of the weight plates; and making a selectorized kettlebell 600 using a second subset of the weight plates. An additional step may involve making a second plurality of identical weight plates 580 or 590, wherein the weight plates in the second plurality are different than the weight plates in the plurality, in which case, the selectorized dumbbell 500 is made using a first subset of the weight plates in the second plurality, and the selectorized kettlebell 600 is made using a second subset of the weight plates in the second plurality. With regard to the embodiments shown in FIGS. 12 and 13, yet another additional step includes making a plurality of identical weight selectors, wherein the selectorized dumbbell 500 is made using a first subset of the weight selectors, and the selectorized kettlebell 600 is made using a second subset of the weight selectors. Still another step involves making a plurality of identical weight bases 555, wherein the selectorized dumbbell 500 is provided with a first subset of the weight bases by connecting two said bases a fixed distance apart from one another to support the weights associated with the dumbbell, and the selectorized kettlebell 600 is provided with a second subset of the bases by using one of said bases to support the weights associated with the kettlebell. Such a method may also be described in terms of making the dumbbell 500 to support an arrangement of weights at a first end of a handle 514, and to support an identical said arrangement of weights at an opposite, second end of the handle 514, and making the kettlebell 600 to support an identical arrangement of weights beneath a handle 614.

[0071] Generally speaking, the kettlebell 600 may be described in terms of a truncated version of the dumbbell 500, with the handle 514 replaced by an over-arching handle 614, and the resulting handle member 610 configured to weigh 5 pounds instead of 10 pounds. The knob 609 is similar to the knob 509 (including comparable openings 608), but bears different weight indicia because the kettlebell 600 adjust from 5 to 40 pounds in 5 pound increments.

[0072] The handle member 610 includes support members 611 and 612 that are preferably stamped steel plates that are welded to one another. A bottom end of the member 611 is configured and arranged to extend horizontally to define an anti-tipping member or foot 662, and a comparable foot 661 is disposed on an opposite end of the kettlebell 600, beneath the knob 609. Each foot 661 and 662 is disposed at an elevation just above the bottoms of the weight plates 570, 580, so the weight plates will be first to encounter an underlying horizontal surface. When the kettlebell 600 is used with fewer than all of the weight plates 570, 580, and 590 secured thereto, the feet 661 and 662 help maintain the kettlebell 600 in an upright position (like the position shown in FIG. 15).

[0073] The handle 614 is preferably a cast iron part having a first end of the handle 614 is preferably secured to an upper end of member 611 by welding, and having a distal second end 615. In other words, the handle 614 is cantilevered relative to the member 611, thereby defining an unobstructed gap or opening 606 between the handle end 615 and the underlying weight supporting section of the kettlebell 600. The distal end 615 of the handle 614 preferably has a larger cross-section than an intermediate portion of the handle 614 to help prevent the handle 614 from slipping through a user's grip.

[0074] The present invention may also be described in terms of various other methods relative to the apparatus disclosed herein. For example, the present invention may be described in terms of a method of adjusting resistance to exercise, including the steps of providing a lifting member having at least one weight holder; providing weights sized and configured to occupy the at least one weight holder; mounting a weight selector on the lifting member for movement along a path between a first position, underlying one of the weights, and a second position, free to move upward relative to said one of the weights; and mounting a knob on the handle member for rotation about an axis extending parallel to the path, with a contoured surface on the knob that bears against the weight selector in a manner that alternatively holds the weight selector in the first position and the second position as a function of orientation of the knob relative to the handle member.

[0075] In a more general sense, the present invention may be described in terms of an exercise device, comprising: a weight lifting member; weights sized and configured to align with the weight lifting member; a weight selector movably mounted on the weight lifting member for movement between a first position, underlying one of the weights, and a second position, free to move upward relative to said one of the weights; and a knob rotatably mounted on the weight lifting member for rotation about a knob axis, wherein a contoured bearing surface on the knob bears against the weight selector to alternatively hold the weight selector in the first position and the second position as a function of orientation of the knob relative to the weight lifting member.

[0076] This disclosure will enable persons skilled in the art to derive additional modifications, improvements, and/or applications that nonetheless embody the essence of the invention. For example, it may be desirable to replace the coil springs with leaf springs or foam rubber. Also, it may be desirable to eliminate the springs altogether and instead, provide “two-sided bearing surfaces” on the knobs to both push and pull the selectors in response to rotation. Moreover, similar weight selecting arrangements may be provided on weight stack machines, especially in connection with the selection of supplemental weights that weigh a fraction of each weight plate in the primary stack. In view of the foregoing, the scope of the present invention should be limited only to the extent of the following claims.