Abstract:
An exercise apparatus includes a cable that is extracted from a housing when the extraction force is sufficient to rotate a drum that is rotatably mounted within the housing. A brake material is sandwiched between the drum and at least one tension band to provide adjustable resistance to rotation of the drum. A knob is rotated to adjust tension in the at least one tension band without affecting tension in the brake material. Indicia associated with rotation of the knob show changes in the resistance level as the knob rotates through more than one complete revolution relative to the housing.

Description:
FIELD OF THE INVENTION 
     The present invention relates to exercise methods and apparatus, and more specifically, to the provision of selectively adjustable resistance to exercise motion. 
     BACKGROUND OF THE INVENTION 
     A variety of exercise devices have been developed to resist exercise motion. For example, U.S. Pat. No. 6,726,607 to Ihli and U.S. Pat. No. 7,087,001 to Ihli disclose exercise resistance devices that are compact and selectively adjustable. An object of the present invention is to provide improved exercise resistance devices that are compact and selectively adjustable. 
     SUMMARY OF THE INVENTION 
     The present invention involves exercise resistance devices having a drum rotatably mounted on a frame; at least one tension band disposed about at least a portion of the perimeter of the drum; a tension adjustment mechanism interconnected between the tension band(s) and the frame; and a force receiving member operatively connected to the drum in such a manner that movement of the force receiving member is linked to rotation of the drum. 
     One feature of the present invention is the provision of a braking strip disposed between the tension band(s) and the drum. The braking strip is preferably arranged so adjustments to the tension in the tension band(s) do not affect the tension in the braking strip. The braking strip preferably has one end secured to the drum and the other end resting on the perimeter of the drum. The braking strip is preferably a Kevlar™ strap. 
     Another feature of the present invention is the provision of diametrically opposed first and second tension bands. Each band preferably has a first end connected to the frame, and a second end connected to a respective nut. The nuts are preferably threaded onto respective ends of an adjustment bolt rotatably mounted on the frame. One nut and associated end of the bolt is reverse-threaded relative to the other nut and associated end of the bolt, and both nuts bear laterally against the frame. As a result, the nuts are constrained to move in opposite directions in response to rotation of the bolt. 
     Yet another feature of the present invention is the provision of a housing about the drum. In this regard, the frame preferably includes a bracket sandwiched between a front housing and a rear housing. The front housing and the rear housing preferably cooperate to define a shell that fits into a person&#39;s hand. A strap is preferably secured between protruding first and second portions of the bracket to extend across the back of the person&#39;s hand when the shell is held in the person&#39;s hand. 
     The foregoing features of the present invention may be practiced individually and/or in any combination with one another and/or with other features that will become apparent from the more detailed description that follows. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWING 
       With reference to the Figures of the Drawing, wherein like numerals represent like parts and assemblies throughout the several views: 
         FIG. 1  is a diagrammatic view of a person exercising with two identical units of a preferred embodiment exercise apparatus constructed according to the principles of the present invention; 
         FIG. 2  is a perspective view of one of the exercise apparatus shown in  FIG. 1 , but without the cord or the carabineer; 
         FIG. 3  is a side view of the exercise apparatus of  FIG. 2 ; 
         FIG. 4  is the same side view as  FIG. 3 , but with the near side of the exterior housing removed to illustrate the interior components; 
         FIG. 5  is an opposite, inside view of the housing component shown in  FIG. 3 , and removed for  FIG. 4 ; 
         FIG. 6  is an opposite side view of the exercise apparatus of  FIG. 2 ; 
         FIG. 7  is the same side view as  FIG. 6 , but with the near side of the exterior housing removed to illustrate the interior components; 
         FIG. 8  is an opposite, inside view of the housing component shown in  FIG. 6 , and removed for  FIG. 7 ; 
         FIG. 9  is a top view of the exercise apparatus of  FIG. 2 ; 
         FIG. 10  is the same top view as  FIG. 9 , but with the front and rear housing components removed to illustrate the interior components; 
         FIG. 11  is an end view of the exercise apparatus of  FIG. 2 ; 
         FIG. 12  is a perspective view of a bracket that is part of the exercise apparatus of  FIG. 2 ; 
         FIG. 13  is a perspective view of a brake drum that is part of the exercise apparatus of  FIG. 2 ; 
         FIG. 14  is an end view of certain internal components of the exercise apparatus of  FIG. 2 ; and 
         FIG. 15  is a perspective view of an alternative embodiment brake band that may be substituted onto the exercise apparatus of  FIG. 2 . 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     In a certain respect, the present invention may be described in terms of improvements to the exercise apparatus disclosed in U.S. Pat. No. 6,726,607 to Ihli and U.S. Pat. No. 7,087,001 to Ihli, both of which are incorporated herein by reference to contribute to understanding of the construction, operation, and/or use of the present invention. As a result, the following description focuses primarily on distinctions between these prior art devices and the present invention, and takes into account the fact that shared attributes are already disclosed in the above-referenced patents. Nonetheless, the features of the present invention may also be implemented on or in connection with other types of exercise apparatus, as well. 
       FIG. 1  shows an adult male Q exercising with two identical units  100  of an exercise apparatus constructed according to the principles of the present invention. One unit  100  fits into the palm of the person&#39;s left hand LH, and includes a strap  116  that wraps about the back of the person&#39;s left hand LH. The other unit fits into the palm of the person&#39;s right hand RH, and includes a strap  116  that wraps about the back of the person&#39;s left hand RH. The units  100  are shown connected to one another in a manner that accommodates various upper body exercises. In this regard, a cord  102  emanates from the left hand unit  100 ; a carabineer  106  is secured to the end of this cord  102 ; and this carabineer  106  is connected to an eyelet on the other, right hand unit  100 . Similarly, a cord  102  emanates from the right hand unit  100 ; a carabineer  106  is secured to the end of this cord  102 ; and this carabineer  106  is connected to an eyelet on the other, left hand unit  100 . This arrangement of the two units  100  is only one example of how the subject invention may be used for exercise purposes. For example, various force receiving members may be connected to the carabineer  106  on a unit  100 , and/or a unit  100  may be supported by various elements other than a person&#39;s hand, including, for example, a body harness, a platform, a bench, a bed, or a post. 
     Various components of one of the units  100  are shown in  FIGS. 2-14  (all of which are drawn to scale). Each unit or apparatus  100  preferably includes a frame comprising an injection molded front housing or shell half  120 , an injection molded rear housing or shell half  140 , and a stamped steel bracket  160  sandwiched between the housings  120  and  140 . In this regard, five threaded inserts  114  (see  FIG. 4 ) are secured in respective receptacles  144  in the rear housing  140  (see  FIG. 8 ), and five screws  112  (see  FIG. 3 ) are inserted through holes  122  in the front housing  120  (see  FIG. 5 ), and through holes  162  in or past edges of the bracket  160  (see  FIG. 12 ), and threaded into the inserts  114 .  FIG. 5  shows the front housing  120  by itself;  FIG. 8  shows the rear housing  140  by itself; and  FIG. 12  shows the bracket  160  by itself. 
     As shown in  FIGS. 4 and 7 , the bracket  160  includes a first tab  163  that projects outwardly through a first gap defined between opposing edges of the front housing  120  and the rear housing  140 , and a diametrically opposed, second tab  164  that projects outwardly through a second gap defined between opposing edges of the front housing  120  and the rear housing  140 . As shown in  FIG. 12 , each tab  163  and  164  defines an identical slot  161  that is sized and configured to accommodate a section of the strap  116 . As shown in  FIGS. 2-3  and  6 , the ends of the strap  116  are inserted through respective slots  161  and connected to one another in overlapping fashion by hook-and-loop type fasteners. The strap  116  is preferably made of woven Nylon material. 
       FIG. 12  shows three holes  162  in the bracket  160 , through which respective screws  112  are inserted, and a large central opening  169 .  FIG. 12  also shows a third tab  165  on the bracket  160 , and the eyelet  166  that extends through the third tab  165 . As shown in  FIGS. 4 and 7 , the third tab  165  projects outward through a third gap defined between opposing edges of the front housing  120  and the rear housing  140 . 
     As shown in  FIG. 1 , the cord  102  extends from the carabineer  106  into a re-directional bearing  200  rotatably retained between the housings  120  and  140 . As shown in  FIGS. 9-10 , the re-directional bearing  200  includes a base  202  and a centrally located slot  204  extending through an upper forward portion of the base  202 . For manufacturing purposes, the base  202  comprises two similar injection molded halves that are secured together by a threaded insert and a screw  201  (see  FIGS. 3-4 ), and also by a commercially available C-clip  209  (see  FIGS. 4 and 7 ). The re-directional bearing  200  also includes a commercially available bearing pack  208  that is mounted onto a bottom stem portion of the base  202  (prior to attachment of the C-clip  209 ). The front housing  120  includes a half-receptacle  132  (see  FIG. 5 ) for the base  202  and the bearing pack  208 , and the rear housing  140  similarly includes a half-receptacle  152  (see  FIG. 8 ) for the base  202  and the bearing pack  208 . 
     The slot  204  extends through a front portion of the base  202  and a top portion of the base  202 . A first steel pin  205  is rotatably mounted to the base  202  and extends across a radially outward portion of the slot  204 . A second steel pin  206  is rotatably mounted to the base  202  and extends across a radially inward portion of the slot  204 . The cord  102  is routed downward between the two pins  205  and  206 , and then downward through a forwardly eccentric bore extending through the base  202  (see  FIGS. 9-10 ). The components of the re-directional bearing  200  cooperate to keep the cord  102  bearing against the forward pin  205  as the cord  102  is pulled anywhere in a hemispherical space centered about the rotational axis of the re-directional bearing  200  and bounded by a plane defined by the exposed interface between the base  202  and the housings  120  and  140 . 
     The cord  102  extends from the bore in the re-directional bearing  200  to a cord guide  210 , which is shown in  FIG. 14  (together with components of a knob assembly described elsewhere). The cord guide  210  includes an injection molded base  211  having a first tab  212  that extends in a first direction, and a second tab  214  that extends in an opposite, second direction. A slot  216  extends through the base  211  between the tabs  212  and  214 . A first steel pin  218  extends along one longer side of the slot  216 , and is rotatably mounted on the base  211 . Similarly, a second steel pin  219  extends along an opposite longer side of the slot  216 , and is rotatably mounted on the base  211 . As shown in FIGS.  5  and  7 - 8 , the cord guide  210  is secured between the housings  120  and  140 , with the first tab  212  inserted into a receptacle  131  in the front housing  120  (see  FIG. 5 ), and the second tab  214  inserted into a receptacle  151  in the rear housing  140  (see  FIG. 8 ). A portion of the base  211  adjacent the first tab  212  bears against the bracket  160 . The cord  102  is routed downward between the pins  218  and  219  and then about a sheave  180 . The pins  218  and  219  cooperate to keep the cord  102  from riding against respective sidewalls of the sheave  180  when the cord  102  is pulled in any plane that extends substantially perpendicular to the bracket  160 , thereby rotating the bore out of alignment with the sheave  180 . 
     Portions of the sheave  180  are shown in  FIGS. 4 ,  7 , and  10 . The sheave  180  is functionally equivalent to the sheave disclosed in the above-referenced Ihli patents, so many of its features are not shown in detail in the accompanying Figures. The sheave  180  includes injection molded opposing sidewalls that define a groove  182  therebetween. The cord  102  has an inner end secured to the sheave  180  at the base of the groove  182 , and the cord is wound about the base of the groove  182  and then itself. 
     A one-way clutch bearing is press-fit into the hub of the sheave  180 , and a steel cylindrical shaft  110  is inserted through the one-way clutch bearing. The arrangement is such that the sheave  180  rotates together with the shaft  110  when the cord  102  is pulled from the sheave  180 , and the sheave  180  rotates relative to the shaft  110  when the cord is wound back onto the sheave  180 . 
     The sheave  180  includes an injection molded cylindrical cover that snaps into place on the outboard sidewall of the groove  182 . The cover provides a housing for a concentrically wound, spring steel, recoil spring (not shown). A radially outer end of the spring is connected to the outboard sidewall of the groove  182 . An opposite, radially inner end of the spring is connected to the rear housing  140  via a pin  184  (see  FIG. 7 ) inserted into either of two holes  148  in the rear housing (see  FIG. 8 ). As a result of this arrangement, the spring biases the cord  102  toward a retracted state within the housings  120  and  140 , and wound about the sheave  180 . In other words, the spring biases the sheave  180  to rotate in a rewind direction relative to the shaft  110 , and resists rotation of the sheave  180  together with the shaft  110  when the cord  102  is pulled from the sheave  180 . 
     As shown in  FIG. 7 , a first end of the shaft  110  inserts through a bearing pack  111 , and a Teflon™ (or a Polytetrafluorethylene (PTFE)) washer  118  is disposed on the shaft  110  between the bearing pack  111  and the sheave  180 . As shown in  FIG. 8 , the rear housing  140  includes a reinforced receptacle  141  for the bearing pack  111 . Similarly, as shown in  FIG. 4 , an opposite, second end of the shaft  110  inserts through an identical bearing pack  111 , and a Teflon™ washer  119  is disposed on the shaft  110  between the bearing pack  111  and a brake drum  190 . As shown in  FIG. 5 , the front housing  120  includes a reinforced receptacle  121  for the bearing pack  111 . 
     The injection molded brake drum  190  is shown by itself in  FIG. 13 . The brake drum  190  is keyed to the shaft  110  and thereby constrained to rotate together with the shaft  110 . In this regard, a hole extends transversely through the shaft  110 , and a pin  109  (see  FIG. 4 ) is inserted through the hole in the shaft  110 . As shown in  FIG. 13 , the brake drum  190  includes a slot  191  to receive the pin  109  when the pin  109  is pushed half-way through the hole in the shaft  110 . 
     The brake drum  190  defines a circumferential perimeter or bearing surface  192 . A circular parting line  193  is centrally located about the bearing surface  192 , and the bearing surface  192  angles in opposite directions away from the parting line  193 , thereby giving the bearing surface  192  a slightly inverted V-shaped profile. Staggered divots or notches  194  extend into respective lateral edges of the bearing surface  192  at circumferentially spaced locations about the bearing surface  192 . The notches  194  and/or the centerline  193  may be described as at least one centering feature that encourages a braking strip  290  to remain centered on the perimeter  192  of the drum  190 . A texture pattern may also be applied to the bearing surface  192  to define such a centering feature. The braking strip  290  (see  FIG. 4 ) is preferably a Kevlar™ (or a para-aramid synthetic fiber) strap having a first end that is folded against itself and sewn into a doubly thick end, and a second end that is terminated in a manner that discourages fraying. 
     A radially extending slot  195  interrupts the perimeter  192  of the drum  190  and receives the doubly thick end of the braking strip  290 . One sidewall of the slot  195  defines a right angle corner with the perimeter  192  of the drum  190 , while the opposite sidewall of the slot  195  forms a filleted or rounded juncture  196  with the perimeter  192  of the drum  190 . The slot  195  is slightly thinner than the braking strip  290  at its radially outward end, and at least twice as wide at its radially inward end. Also, laterally extending ridges extend along the sidewalls bordering the radially outward end of the slot. The doubly thick end of the braking strip  290  is inserted into the radially inward end of the slot  195 , and the adjacent thinner portion of the braking strip  290  is inserted into the radially outward end of the slot  195 . The subsequent adjacent portion of the braking strip  290  is wrapped about the rounded corner  196  and then around the perimeter  192  of the drum  190 . The length of the braking strip  290  is such that the free end may be pulled to the right angle corner of the slot  195 , but not into contact with the portion of the braking strip  290  emanating from the slot  195 . As a result of this arrangement, the rounded corner  196  pulls the wrapped portion of the braking strip  290  through circles in response to withdrawal of the cord  102  from the sheave  180 . 
     For strength and manufacturing efficiency, the drum  190  is cored to an extent, and holes  198  extend through an intermediate section of the drum  190 . The holes  198  align with a cord  102  tie-off point associated with the sheave  180 , thereby providing access for replacing the cord  102  with a new cord  102 , if and when needed. 
     As shown in  FIG. 4 , a first tension band  273  is secured in a generally U-shaped configuration about one half of the braking strip  290  and underlying perimeter  192  of the drum  190 , and a second tension band  274  is secured in a generally U-shaped configuration about an opposite half of the braking strip  290  and underlying perimeter  192  of the drum  190 . Each tension band  273  and  274  is preferably a strip of stainless spring steel that is formed into a stable U-shaped configuration prior to installation on the unit  100 . 
     A first end of the first tension band  273  is anchored to a fourth tab  173  on the bracket  160  (see  FIG. 12 ). Similarly, a first end of the second tension band  274  is anchored to an identical fifth tab  174  on the bracket  160  (see  FIG. 12 ). In this regard, first and second holes  175  extend through each tab  173  or  174 , and comparable holes extend through the first end of each tension band  273  and  274 , and pairs of first and second screws  107  (see  FIG. 4 ) insert through respective tension bands  273  and  274  and thread into respective holes  175 . An opposite, second end of the first tension band  273  is anchored to a first steel adjustment nut  253  by means of comparable holes in the nut  273  and the second end of the first tension band  273 , and identical first and second screws  107 . Similarly, an opposite, second end of the second tension band  274  is anchored to a second steel adjustment nut  254  by means of comparable holes in the nut  274  and the second end of the second tension band  274 , and identical first and second screws  107 . 
     The first nut  253  is threaded onto RH threads  243  on a first end of an adjustment bolt  240 . The second nut  254  is threaded onto LH threads  244  on an opposite, second end of the adjustment bolt  240 . Each nut  253  and  254  has a flat side that bears against a respective flat portion of the bracket  160 . 
     The adjustment bolt  240  is rotatably mounted on the bracket  160 . In this regard, as shown in  FIGS. 4 and 12 , the first end of the adjustment bolt  240  is inserted through a hole  177  in a sixth tab  176  on the bracket  160 , and an opposite, second end of the adjustment bolt  240  is dropped into a slot  179  in a seventh tab on the bracket. As shown in  FIG. 5 , rails  133  and  134  on the front housing  120  are configured and arranged to bear against the tops of respective nuts  253  and  254  to prevent the adjustment bolt  240  from rising out of the slot  179 . Also, stops are provided at the ends of the rails  133  and  134  to limit axial travel of the nuts  253  and  254  along the adjustment bolt  240 . 
     A steel and nylon lock nut  246  is threaded onto the second end of the bolt  240 , with a Teflon™ (or a Polytetrafluorethylene (PTFE)) washer disposed on the second end of the bolt between the lock nut  246  and the seventh tab  178  on the bracket  160 . A knob  230  is keyed (see  FIG. 14 ) and pinned (see pin  248  in  FIG. 10 ) to the first end of the bolt  240 , with a Teflon™ washer disposed on the first end of the bolt  240  between the knob  230  and the sixth tab  176  on the bracket  160 . The knob  230  and the lock nut  246  cooperate to prevent axial movement of the bolt  240  relative to the bracket  160 . The arrangement of the nuts  253  and  254  and the bolt  240  is such that the nuts  253  and  254  move away from one another when the bolt  240  is rotated in a first direction, and move toward one another when the bolt  240  is rotated in an opposite, second direction. In other words, from the perspective of a person facing the unit  100  as shown in  FIG. 11 , rotation of the knob  230  in a clockwise direction causes the nuts  253  and  254  to move away from one another, thereby increasing resistance to rotation of the drum  190 , and rotation of the knob  230  in a counter-clockwise direction causes the nuts  253  and  254  to move toward one another, thereby decreasing resistance to rotation of the drum  190 . 
     The knob  230  is an assembly of four injection molded parts. As shown in  FIGS. 6 ,  11 , and  14 , the knob  230  includes a base  232  that is keyed to the shaft  110 , and pinned to the shaft  110  by pin  248 . A two-pronged latch  236  is keyed to the base  232  with the prongs straddling the shaft  110 . A dial  238  has a neck portion (not shown) that is rotatably mounted on the end of the shaft  110  (via a cylindrical bore in the neck portion), and that has an octagonal outer profile with opposing sides sized and configured to fit snugly between the prongs of the latch  236 . The prongs are leaf springs that discourage rotation of the dial  238 , but resiliently deflect to accommodate rotation of the dial  238  relative to the shaft  110  (and the base  232 ). A cap  234  snaps onto the base  232  to capture the dial  238  and the leaf spring  236 , and is keyed to the base  232  for rotation together therewith. A fin on the dial  238  extends in a direction opposite the neck portion to accommodate grasping of the dial  238  between a person&#39;s thumb and forefinger. A nub  239  on one end of the fin provides a visual indication of the orientation of the knob  230  and the shaft  110 . The dial  238  is selectively rotated relative to the knob  230  and the shaft  110  to recalibrate the orientation of the nub  239  as an indication of relative resistance to rotation of the drum  190  (in increments of 45 degrees). 
     As shown in  FIG. 4 , an injection molded indicator finger or pointer  255  is rigidly secured to the adjustment nut  253  by means of one of the screws  107  (and a slot in the nut  253 ). As a result, the pointer  255  travels linearly together with the nut  253 . As shown in  FIG. 3 , the finger  255  is visible through an injection molded window  105  mounted on the front housing  120  (via adhesive or other known suitable means).  FIG. 5  shows a receptacle  125  for the window  105  in the front housing  120 . The window  105  includes staggered and alternating hash marks along its upper and lower visible edges. The position of the finger  255  relative to the hash marks on the window  105  indicates a relative range of resistance associated with a revolutionary increment of the knob  230 . In other words, the location of the finger  255  provides a macro reading of relative resistance, and the orientation of the indicator  239  provides a micro reading of relative resistance. Each time the knob  230  goes through a revolution, the indicator  239  returns to the same orientation, but the finger  255  moves to a different position relative to the hash marks on the window  105 . The adjustability of the dial  238  allows one unit  100  to be calibrated relative to another unit  100  with regard to the micro reading of relative resistance. 
       FIG. 15  shows an alternative embodiment tension band  370  that is substituted for the tension bands  273  and  274  on an alternative embodiment of the present invention. The tension band  370  has a first end  373  that is screwed to the adjustment nut  253 , and an opposite, second end  374  that is screwed to the adjustment nut  254 . A slot  376  extends through a first portion of the tension band  370 , proximate the first end  373 . A portion  377  of the tension band  370 , proximate the second end  374 , is necked down or narrowed to pass through the slot  376  with minimal clearance. The slot  376  and the narrowed portion  377  allow the tension band  370  to be arranged into a closed loop, in the same general way that the tension bands  273  and  274  are interlaced. 
     The subject invention has been described with reference to a preferred embodiment with the understanding that features of the subject invention may be practiced individually and/or in various combinations and/or on various types of exercise equipment. Also, persons skilled in the art will recognize that various modifications may be made to the preferred embodiment, in any of its applications, without departing from the scope of the subject invention. Furthermore, alternative embodiments may be made with different component materials, structures, and/or spatial relationships, and nonetheless fall within the scope of the present invention. In view of the foregoing, the subject invention should be limited only to the extent of the claims set forth below.