Patent Publication Number: US-7223215-B2

Title: Exercise device with true pivot point

Description:
This application is a continuation-in-part of application Ser. No. 09/737,209 filed Dec. 14, 2000 now U.S. Pat. No. 6,773,378. The contents of application Ser. No. 09/737,209 are incorporated herein by reference. 

   FIELD OF THE INVENTION 
   The present invention pertains generally to physical exercise devices. More specifically, the present invention pertains to portable exercise devices and methods for using these devices. The present invention is particularly, but not exclusively, useful as an adjustable exercise device which allows the individual user to selectively stabilize the device during an exercise routine. 
   BACKGROUND OF THE INVENTION 
   As is well known, a wide variety of exercise equipment is commercially available for purchase and use by individuals for purposes of developing their overall strength and physical condition. Often this equipment is designed for specific purposes, such as for exercising targeted muscle groups. The more complex and comprehensive the exercises become, however, it often happens that the exercise equipment also becomes more complex, more bulky, and less mobile. Similarly, exercise equipment that is designed for multiple exercises and for exercising multiple muscles becomes more complex, bulky and less mobile. 
   In general, exercise equipment can be categorized as being either stationary equipment or portable equipment. Typically, stationary equipment is found in gyms, athletic facilities, training centers, and to a lesser degree in homes, and involves floor-mounted frames that normally incorporate heavy weights or other force generating mechanisms. An important reason for using stationary exercise equipment is that such equipment adds an element of stability to an exercise routine and provides a means for reacting forces being applied by the user to the equipment. In many exercise routines, and particularly those that are designed for physical therapy purposes, this element of stability may be very desirable. For instance, whenever there is a targeted muscle group, it may be important to insure that the muscle group is properly exercised. This means the exercise routine should involve repetitively consistent muscle contractions against a resistance of predictable magnitude and direction. To achieve these objectives, it is necessary to somehow stabilize the equipment. This is easily done with stationary equipment. By definition, however, stationary equipment is not portable and requires a dedicated area for its location. 
   The use of portable exercise equipment has several advantages. One such advantage is availability. The convenience of being able to carry the equipment from site to site can be of considerable value to a user. This value can be significantly increased if the equipment itself is relatively light-weight and easy to handle. Further, as implied above in the context of stationary equipment, the versatility of portable exercise equipment can be significantly increased if it is somehow capable of being stabilized so that it is possible to reliably and consistently perform the repetitions of an exercise routine and be used at physiologically significant load levels. It is a further advantage if the portable exercise equipment can be quickly, easily, and conveniently configured for use when initiating an exercise session, and for performing a variety of exercise routines. 
   In light of the above, it is an object of the present invention to provide a portable exercise device which can be stabilized during an exercise routine. Another object of the present invention is to provide an exercise device which includes an adjustable mechanism that will reliably and repeatedly provide a desired resistance to the user during an exercise routine. Another object of the present invention is to provide an exercise device that can be easily and quickly configured by the user to perform a variety of exercises. Another object of the present invention is to provide an exercise device that can be used for exercising various muscles within the body of the user. Another object of the present invention is to provide an exercise device that does not interfere with or constrain normal joint biomechanics during the user&#39;s performance of exercise routines with the device. Another object of the present invention is to provide an exercise device for use by an individual which is compact, portable, and safe. Yet another object of the present invention is to provide an exercise device which is relatively simple to manufacture, is easy to use and is comparatively cost effective. 
   Other objects, features and advantages of the present invention will become apparent from the following description, taken in conjunction with the accompanying drawings, which illustrate, by way of example, the principle of the invention. 
   SUMMARY OF THE INVENTION 
   An exercise device includes a first arm, a second arm and a joint assembly that interconnects the first arm with the second arm. In one embodiment, a third arm is included that rotates together with the second arm. For reference purposes, the joint assembly defines an axis of rotation that is substantially perpendicular to both the first arm and the second arm. Within this assembly, the first arm can be considered as having a fixed relationship with respect to the axis. On the other hand, the second arm is able to rotate about the axis. More specifically, the second arm (and in some cases a third arm) is able to rotate freely in one direction around the axis, while being restrained by a resistance during a rotation in the opposite direction. 
   Included in the joint assembly is a one-way clutch that is fixed to a cone member. A shaft that is fixed to the second arm is positioned within the one-way clutch. Through the action of the one-way clutch, the cone member moves together with the second arm when the second arm is moved in a first direction, but it does not move with the second arm when the second arm is moved in the opposite direction. Also included in the joint assembly, along with the cone member, are a cup member and a friction liner. More specifically, both the cone member and the cup member have tapered surfaces that conform to each other, and the friction liner is positioned between these surfaces at their interface. Further, the cup member is connected directly to the first arm. An alternate embodiment is envisioned for the present invention which will not employ the one-way clutch. In this embodiment the cone member will move with the second arm in both directions. 
   In the operation of the exercise device, the first arm is stabilized and the second arm rotates freely about a rotation axis in the direction wherein the one-way clutch does not engage the second arm with the cone member. Specifically, the shaft rotates freely within the one-way clutch. On the other hand, when the second arm is moved in the opposite direction, i.e. the direction wherein the one-way clutch fixedly engages the shaft with the cone member, the second arm will encounter resistance to rotation. Specifically, when the one-way clutch becomes engaged, the tapered surface of the cone member will move relative to the tapered surface of the cup member. This movement will involve the friction liner and will generate a force that resists the rotation and is substantially constant throughout the movement. It will be appreciated by the skilled artisan that whenever there is no relative movement between the arms, i.e. when the second arm is stationary relative to the first arm, there is zero stored energy in the exercise device. 
   Several alternate embodiments are envisioned for the present invention which will respectively use different mechanisms for generating a one-way or two-way resistance to the relative movement between the second arm and the first arm. Specifically, a spring or an elastomeric material can be positioned in the joint assembly and oriented to resist any relative movement of the second arm in a predetermined direction of rotation. Further, pneumatic, hydraulic, viscous shear, magnetic or electromagnetic systems can be used for this purpose. 
   In one embodiment of the exercise device, control over the amount of the resistance there is to a rotation of the second arm, relative to the first arm, is accomplished at the joint assembly. Specifically, for this purpose the joint assembly can include a knob which is mounted on the cup member. This knob has a threaded connection with a plunger so that rotations of the knob will cause a translational movement of the plunger. The plunger, in turn, is in contact with a spring which is compressed or allowed to elongate with rotations of the knob, and this spring interacts with the cone member. Thus, in combination, a rotation of the knob activates the spring to urge the tapered surface of the cone member against the friction liner on the tapered surface of the cup member. Accordingly, depending on the direction the knob is rotated, the resistance to rotation between the cup member and cone member can be increased or decreased. There may also be a spring-loaded detent that is mounted on the cup member so that when the knob is turned, the detent is urged against detent notches in the knob to provide an aural signal in response to the rotation of the knob. 
   In another embodiment of the exercise device, a lever is provided to adjust the rotation resistance of the second arm, relative to the first arm. For this embodiment, a plate is attached to the cup member and a threaded extension is attached to the lever. The extension is threadably engaged with the plate and a spring is interposed between the threaded extension and the cone member. With this cooperation of structure, the lever can be moved by the user to rotate the threaded extension and thereby selectively compress or expand the spring. The spring, in turn, establishes a rotation resistance between the cup member and cone member at their interface. Thus, in combination, a movement of the lever activates the spring to urge the tapered surface of the cone member against the friction liner on the tapered surface of the cup member. Accordingly, depending on the direction the lever is moved, the resistance to rotation between the cup member and cone member can be increased or decreased. 
   As indicated above, the first arm of the device is stabilized as the second arm of the device is rotated against the resistance created by the resistance mechanism. To do this, the first arm is stabilized by a base member at an end opposite the joint assembly. In one embodiment, the base member is a foot pedal, and in another embodiment the base member is a frame that includes a seat for the user. Alternatively, however, the stabilizing mechanism may be a friction surface, a mounting bracket, a handle, or some other suitable stabilizing element. 
   The second arm can include an input mechanism that is located at the end of the second arm opposite the joint assembly. Preferably, this mechanism is a handle that can be placed in a variety of positions. 
   The present invention also envisions that a position sensor can be mounted on the device to monitor repetitions in an exercise routine. If used, the sensor can generate signals which represent changes in the relative positions of the arms of the device. These changes can then be timed and used to count repetitions or cycle duration that may be useful for monitoring the exercise routine. A computer or microprocessor interface can also be established to monitor the signals that are generated by the position sensor. 
   It is further envisioned that a load or strain sensor can be mounted on the device to monitor the load applied by the user of the device to rotate the second arm against the resistance created by the resistance mechanism. If used, the sensor can generate a signal that is proportional to the magnitude of force applied by the user of the device. This signal can be used to calculate the peak, average, and minimum load applied by the user in each exercise cycle. The signal can also be monitored and timed to count repetitions or cycle duration. A computer or microprocessor interface can also be established to monitor the signals that are generated by the load or strain sensor, and to calculate and display other useful exercise information. 
   During an exercise routine, the exercise device of the present invention can be used by an individual to perform, for example, biceps exercises. To do this, the individual sets the resistance according to his or her strength and exercise goals. Once the resistance is set, the individual user then stabilizes the first arm of the device by stepping on the foot pedal (if provided) or for some exercises by sitting on the seat (if provided). While positioning the elbow in close alignment with the axis of rotation of the joint assembly, the individual can then grasp the handle that is attached to the extended end of the second arm. The second arm can then be rotated in a clockwise or a counterclockwise rotation about the joint assembly. In one scenario, a clockwise rotation produces resistance as the targeted muscles contract. During a counterclockwise rotation, however, the resistance is released, and the second arm can be returned to its initial position. For subsequent exercise routines, the resistance can be increased as the muscles become stronger. Further, the device can be easily and quickly reconfigured to change the direction of resistance or to change to other configurations so that the user can alter body positions or alter the relationship of the device relative to the user for other exercise routines and for exercising other muscles. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The novel features of this invention, as well as the invention itself, both as to its structure and its operation, will be best understood from the accompanying drawings, taken in conjunction with the accompanying description, in which similar reference characters refer to similar parts, and in which: 
       FIG. 1  is a perspective view of an exercise device shown with peripheral computer equipment; 
       FIG. 2  is a cross sectional view of a joint assembly for an exercise device such as the device shown in  FIG. 1  as would be seen along a line  2 — 2  in  FIG. 1  when the device is straightened; 
       FIG. 3  is a plan view of the interconnection between the plunger and bushing of the joint assembly shown in  FIG. 2 , as seen looking along the axis of rotation shown in  FIG. 2 ; 
       FIG. 4  is an exploded view of a handle assembly; 
       FIG. 5A  is a side elevation view of a user with the exercise device shown in  FIG. 1 , positioned with the joint assembly at the elbow point being exercised) and with the user&#39;s arm extended; 
       FIG. 5B  is a side elevation view of a user with the exercise device shown in  FIG. 1 , positioned with the joint assembly at the elbow (joint being exercised) and with the user&#39;s arm flexed; 
       FIG. 6A  is a side elevation view of a user with the exercise device shown in  FIG. 1 , positioned with the joint assembly remotely positioned and with the user&#39;s arm elevated; 
       FIG. 6B  is a side elevation view of a user with the exercise device shown in  FIG. 1 , positioned with the joint assembly remotely positioned and with the user&#39;s arm lowered; 
       FIG. 7A  is a side view representation of a user operating the exercise device shown in  FIG. 1  with rotation in one direction; 
       FIG. 7B  is a side view representation of the user operating the exercise device shown in  FIG. 1  with a rotation in a direction opposite to the rotation direction shown in  FIG. 7A ; 
       FIG. 8  is a perspective view of an alternative embodiment of an exercise device; 
       FIG. 9  is a perspective view of an alternative embodiment of an exercise device; 
       FIG. 10  is a cross sectional view of a joint assembly for an exercise device as would be seen along line  10 — 10  in  FIG. 9 , after the arms have been rotated to become parallel; 
       FIG. 11  is a perspective, right side view of the joint assembly shown in  FIG. 10 ; 
       FIG. 12  is a perspective, left side view of the joint assembly shown in  FIG. 10 ; 
       FIG. 13  is a partially exploded right side perspective view of the joint assembly shown in  FIG. 10 ; 
       FIGS. 14A and 14B  show an exercise device configured for exercising the chest of a user; 
       FIGS. 15A and 15B  show an exercise device configured for exercising the lower body of a user; and 
       FIGS. 16A and 16B  show an exercise device configured for exercising the gluteus maximus muscle of a user that is in a standing position. 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   A first embodiment of an exercise device is shown in  FIG. 1  and is generally designated  10 . As shown, the device  10  includes a first arm  12 , which has a first end  14  and a second end  16 . The device  10  also has a second arm  18  which has a first end  20  and a second end  22 . As shown in  FIG. 1 , the second arm  18  has a handle  24  that is attached at its second end  22 . It is to be appreciated, however, that the handle  24  can be pivoted about the end  22  through an arc of approximately one hundred and eighty degrees so that the handle  24  extends from the arm  18  in a direction opposite to that shown in  FIG. 1 . Additionally, both the first arm  12  and the second arm  18  have respective locking rings  26   a  and  26   b  that can be manipulated in a manner well known in the art to telescopically adjust the respective lengths of the arms  12  and  18 . 
     FIG. 1  also shows that the device  10  includes a joint assembly  28  which, for reference purposes, defines an axis of rotation  30 . In their relationship to this axis of rotation  30 , the first arm  12  is attached to the joint assembly  28  to establish a fixed relationship between the first arm  12  and the axis of rotation  30 . On the other hand, the second arm  18  is pivotally attached to the joint assembly  28  for a reciprocal rotation of the second arm  18  about the axis of rotation  30 . More specifically, this rotation of the second arm  18  about the axis of rotation  30  can be in either a clockwise direction  32  or in a counterclockwise direction  34 . It is to be appreciated that the second arm  18  as shown in  FIG. 1  can be rotated to other positions about the axis of rotation  30  to establish alternate exercise configurations of the device  10 . 
   In the embodiment of the device  10  shown in FIG. 0.1, a foot pedal  36  is attached to the second end  16  of the first arm  12  such that the foot pedal  36  can rotate about axis  138  or an axis substantially parallel to and in close approximation to axis  138 . During use of device  10 , the foot pedal  36  is placed at a position located approximately ninety degrees relative to arm  12 . However, this angle can vary during use of device  10  to accommodate normal biomechanical motions. For storage, the foot pedal  36  can be rotated to a position next to arm  12 , substantially parallel to axis  136 . It is also envisioned that a position sensor  38  can be mounted on the device  10 , possibly at the joint assembly  28 , to generate signals  40  that are representative of the relative positions of said first arm  12  and said second arm  18  of the device  10 . Specifically, these signals  40  can be generated in a manner well known in the pertinent art and transmitted to a remote computer  42  or other electronic monitoring device for processing. More specifically, the signals  40  can be used to indicate the position of the first arm  12  relative to the second arm  18 , and to measure the time duration between changes in the relative positions of said first arm  12  and said second arm  18  of the device  10 . It is further envisioned that a load sensor  106 , such as a strain gauge, can be mounted on the device  10 , possibly near handle  24 , to generate signals  40  that are representative of the loads that are applied to the handle  24  of device  10 . These signals  40  also can be generated in a manner well known in the pertinent art and transmitted to a remote computer  42  or other electronic monitoring device for processing and displaying useful information regarding exercise sessions. Thus, exercise repetitions, the duration of each repetition, and the load applied by the user  90  ( FIG. 5A ) during each repetition in an exercise routine can be monitored. Furthermore, other exercise performance information and data can be determined from the signals  40 . 
   Turning now to  FIG. 2 , the resistance mechanism that is incorporated into the joint assembly  28  of the device  10  is shown in detail. There it can be seen that the arm  18  is connected to an extension member  44  by means, such as the screw  46 , and that the extension member  44  is connected to a shaft  48  by means, such as the screw  50 . As shown, the shaft  48  is centered on the axis of rotation  30 . Further, the resistance mechanism includes a circular one-way clutch  52 , of a type well known in the pertinent art. The one-way clutch  52  may also have an integral bearing assembly. For example, the one-way clutch can be a Torrington Type DC Roller Clutch and Bearing Assembly, part number RCB-162117. Those of ordinary skill in the art will understand, however, that the one-way clutch  52  may comprise a variety of suitable devices. The one-way clutch  52  is also centered on the axis of rotation  30  and the shaft  48  is formed with a recess  54 . 
   A cone member  56  is included in the joint assembly  28  and is positioned against the one-way clutch  52 . As shown in the preferred embodiment, this cone member  56  is formed with a tapered surface  58  that surrounds the axis of rotation  30  and is angled relative to the axis of rotation  30  at angle β. Preferably, angle β is between ten and fifteen degrees. However, those of ordinary skill in the art will understand that there are many suitable values for angle β including ninety degrees, in which case tapered surface  58  will be substantially perpendicular to the axis of rotation  30 . Additionally, the cone member  56  includes a rim  60  that is oriented radially on the axis of rotation  30 . This rim  60  projects over the recess  54  of the shaft  48  substantially as shown. Also included in the joint assembly  28  is a cup member  62  which has a tapered surface  64 , and which is attached directly to the arm  12  by means such as the screw  66 . Importantly, the tapered surface  64  of the cup member  62  is dimensioned to mate with the tapered surface  58  of the cone member  56 . As intended for the device  10 , a friction liner  68  is positioned between the respective tapered surfaces  58  and  64  of the cone member  56  and the cup member  62 . Preferably, the friction liner  68  is fixed to either the cone member  56  or the cup member  62 . Also, the cup member  62  is formed with an annular groove  70  that is substantially centered on the axis of rotation  30 . 
   Still referring to  FIG. 2 , it is seen that the joint assembly  28  includes a knob  72  that is connected to a threaded ring  74  by means such as the screws  76   a  and  76   b . Further, the ring  74  is threadably engaged with a plunger  78 . As shown, the plunger  78  is formed with a flange  80  that is inserted into the recess  54  of the shaft  48 . Additionally, a force transfer mechanism, such as a spring  82 , and a thrust bearing  110  are positioned in the recess  54  between the flange  80  of plunger  78  and the rim  60  of cone member  56 . The relative position of spring  82  and thrust bearing  110  is interchangeable. For example, the spring  82  can include two Berg belleville washers, part number St- 7 , stacked in a parallel configuration, and thrust bearing  110  can be a Torrington thrust needle roller and cage assembly, part number NTA-411 and two thrust washers, part number TRA-411. However, those of ordinary skill in the art will understand the spring  82  and the thrust bearing  110  may comprise a variety of suitable devices. A bushing  94  is mounted on the cup member  62  and is constrained from rotating about the axis of rotation  30  with respect to cup member  62  by means well known by those of ordinary skill in the art. Flange  100  of the knob  72  is positioned against the bushing  94 , and the knob  72  is constrained from translating along the axis of rotation  30  by radial surface  96  of bushing  94  and from moving in a radial direction relative to the axis of rotation  30  by the annular surface  98  of the bushing  94 . 
   Turning to  FIG. 3 , it is seen that bushing  94  has a key  102  that protrudes into keyway  104  in plunger  78 . The interaction of the key  102  with the keyway  104  prevents the plunger  78  from rotating with respect to the bushing  94  and limits its motion to translation along the axis of rotation  30 . 
   Referring again to  FIG. 2 , a plurality of spring-loaded detents  84 , of which the detents  84   a  and  84   b  are only exemplary, can be mounted on the cup member  62  to urge against the knob  72 . Further, the knob  72  can be formed with a plurality of recesses  86  so that as the knob  72  is rotated, the spring-loaded detents  84  will come into contact with the recesses  86  and thereby make an aural “clicking” sound. The contact of the detents  84  with the recesses  86  also provides incremental rotational setting of the knob  72  wherein there is a slight resistance to rotation of the knob  72  at each of these settings. As an additional matter, it is to be noted that a guide pin  88  is mounted on the extension member  44  and is inserted into the annular groove  70 . Thus, a rotation of the arm  18  around the axis of rotation  30  will be controlled by the interaction of the guide pin  88  in the groove  70 , preventing arm  18 , extension member  44  and shaft  48  from translating along the axis of rotation  30  relative to the cup member  62 . The guide pin  88  is held in position by set screw  112 . 
   In the operation of the device  10 , a user  90  will first adjust the exercise resistance that is to be provided by the joint assembly  28 . Specifically, this is accomplished by rotating the knob  72 . With reference to  FIG. 2 , it will be appreciated by a skilled artisan that a rotation of the knob  72  causes the threaded ring  74  to interact with the plunger  78  in a way that will effect a translational movement of the plunger  78 . Accordingly, depending on the direction that knob  72  is rotated, the plunger  78  will either advance into the recess  54  or be withdrawn from the recess  54 . The consequence of this is that the force transfer mechanism (spring  82 ) will be respectively relaxed or compressed between the flange  80  of plunger  78  and the rim  60  of cone member  56 . In either case, the force that is generated by the spring  82  will act against the cone member  56 . Importantly, this force will be effectively transferred through the cone member  56  to establish a reactive force on the friction liner  68  at the interface between the tapered surface  58  of the cone member  56  and the tapered surface  64  of the cup member  62 . Furthermore, utilizing a force transfer mechanism (spring  82 ) allows the knob  72  to be rotated through larger angles in adjusting the exercise resistance from its lowest setting to its highest setting than would be possible if a force transfer mechanism was not employed. 
   Through the action of the one-way clutch  52 , the arm  18  and its extension member  44  are able to freely rotate about the axis of rotation  30  when the arm  18  is rotated in a predetermined direction, e.g. the clockwise direction  32 . On the other hand, the one-way clutch  52  will fixedly engage the arm  18  with the cone member  56  when the arm  18  and its extension member  44  are rotated in the opposite direction, e.g. the counterclockwise direction  34 . As a consequence, when the arm  18  is fixedly engaged with the cone member  56  through the one-way clutch  52 , the rotation of the arm  18  will encounter the resistance that is established on the friction liner  68  between the cone member  56  and the cup member  62 . As indicated above, the amount of this resistance is established by rotating the knob  72 . Importantly, through the action of key  102  and thrust bearing  110 , plunger  78  and knob  72  are prevented from rotating when the action of the one-way clutch  52  causes cone  56  to rotate with respect to cup  62  as arm  18  is rotated. Further, the audible “clicks” that result when the detents  84   a,b  pass over recesses  86 , together with a visible gauge (not shown), can be used for determining preferred resistance levels. 
   Turning now to  FIG. 4 , the handle assembly  108  of device  10  is shown in detail. There it can be seen that the handle  24  is connected to the outer hub  116  by means such as the shoulder screw  122 . As shown, the shoulder screw  122  is centered on the axis  134   b . The handle  24  is free to rotate about the axis  134   b , out of alignment with axis  134   c , approximately thirty degrees in a clockwise direction and a counterclockwise direction. A plurality of notches  132   a  and a plurality of notches  132   b  are formed on the inside circumference of outer hub  116 . The notches  132   a  are oriented at angle θ with respect to each other. Likewise, the notches  132   b  are oriented at angle θ with respect to each other. Preferably, the angle θ is equal to about ten degrees. The notches  132   a  and  132   b  are oriented one hundred and eighty degrees with respect to each other about axis  134   a . Inner hub  114  has at least one key  130  formed on its outer circumference. The key  130  is dimensioned to mate with the notches  132   a  and the notches  132   b . The inner hub  114  fits within the outer hub  116  such that the key  130  fits securely within one of the notches  132   a  or one of the notches  132   b.    
   The inner hub  114  is attached to the outer hub  116  by the shoulder screw  118  and the spring  120 . The shoulder screw  118  passes through the spring  120  and through the hole  124  in inner hub  114  and threads into the hole  126  in the outer hub  116 . As shown, the screw  118  and the spring  120  are centered on the axis  134   a . The spring  120  is constrained between the head of shoulder screw  118  and the inner surface  128  of the inner hub  114 , biasing inner hub  114  within outer hub  116 . 
   To configure the handle assembly  108  for an exercise routine, the outer hub  116  is translated relative to the inner hub  114  along axis  134   a , compressing the spring  120  to a position where key  130  is clear of the notches  132   a  and the notches  132   b . In this position, the outer hub  116  can be rotated about axis  134   a  to a position where key  130  will align with any of the plurality of notches  132   a  or the plurality of notches  132   b . Preferably, one of the notches  132   a  and one of the notches  132   b  are oriented on the inside circumference of the outer hub  116  such that the handle  24  will be aligned with axis  134   c  when the key  130  engages either of these notches. The inner hub  114  is attached to end  22  of arm  18  by means well known by those skilled in the art. 
   For the device  10 , the ability of the handle  24  to freely rotate about axis  134   b , and to be selectively and fixedly positioned about axis  134   a , allows device  10  to be configured for the correct anatomical position and biomechanical motion of the hand, wrist and joints of the user  90 , both before and during an exercise routine cycle. 
     FIGS. 5A and 5B  show an exemplary use of the device  10  wherein the axis of rotation  30  is positioned close to the axis of rotation of the joint of the user  90  that is to be flexed and extended during an exercise routine. In this example, the elbow of the user  90 . The device  10  is stabilized by the user  90  by stepping on the foot pedal  36 . Rotation of the handle  24  by the user  90  in a counterclockwise direction  34  ( FIG. 5A ) will be met by a resistance force generated by the joint assembly  28  as the arm  18  is rotated about the axis of rotation  30 . Conversely, rotation of the handle  24  by the user  90  in a clockwise direction  32  ( FIG. 5B ) will meet no resistance from the joint assembly  28  as the arm  18  is rotated about the axis of rotation  30 . Further, the direction in which the resistance force acts can be reversed by first rotating the device  10  approximately one hundred and eighty degrees about axis  136  ( FIG. 1 ) and then, if needed, rotating the handle  24  about the axis of rotation  30  or the axis  134   a  to place the handle  24  in the desired position for the exercise to be performed. The arms  12  and  18  can be lengthened or shortened to effect other exercises. 
     FIGS. 6A and 6B  show a use of the device  10  wherein the axis of rotation  30  on the device  10  is positioned at a distance from the axis of rotation of the joint of the user  90  that is to be flexed and extended during the exercise routine. In this example, the shoulder of the user  90 . 
     FIGS. 7A and 7B  show that as an alternative to stabilizing the device  10  by stepping on the foot pedal  36 , the user  90  can otherwise stabilize the device  10  by stepping on the arm  12 . Then, for example, movements of the user  90  from a leaning position ( FIG. 7A ) to a standing position ( FIG. 7B ) can be met by a resistance force. Specifically, this resistance force will be generated by the joint assembly  28  as the arm  18  is rotated about the axis of rotation  30  in the direction  34 . Conversely, movements of the user  90  from the standing position ( FIG. 7B ) to the leaning position ( FIG. 7A ) will meet no resistance from the joint assembly  28  as the arm  18  is rotated about the axis of rotation  30  in the direction  32 . Additionally, in an alternate embodiment of the device  10  shown in  FIG. 8 , the foot pedal  36  can be replaced by a handle  92 . Regardless of which embodiment of the device  10  is contemplated, the position sensor  38  can be used to monitor or guide the exercise routine of the user  90 . For example, in addition to the signals  40  containing time information data, the signals  40  can also convey information about the relative positions of said first arm  12  and said second arm  18  of the device  10 . Thus, returning to  FIGS. 5A and 5B , the signals  40  can include information on the angle α between the arm  12  and the arm  18  ( FIG. 5A ), and changes in this angle α to the angle α′ ( FIG. 5B ). Furthermore, the load sensor  106 , either in combination with the position sensor  38  or alone, can be used with any of the embodiments of the device  10  to monitor or guide the exercise routine of the user  90 . The signals  40  can also contain data regarding the magnitude of the force applied by the user  90  to the device  10  to overcome the resistance force generated by the joint assembly  28  as the arm  18  is rotated from a position at angle α from arm  12  ( FIG. 5A ) to a position at angle α′ from arm  12  ( FIG. 5B ). Additionally, the signals  40  can contain data regarding the magnitude and relative direction of the force applied by the user  90  of the device  10  in returning the arm  18  from angle α′ to angle α. Such information and data, of course, can be useful for monitoring both the duration and the extent of exercise routines conducted with the device  10  as well as the magnitude of the loads applied to the device  10  by the user  90  during the exercise routines. This information and data can also be used by the computer  42  or other electronic monitoring devices to perform calculations and analysis of the exercise routines. 
   Another embodiment of an exercise device is shown in  FIG. 9  and is generally designated  1000 . As shown, the device  1000  includes a first arm  1012 , which has a first end  1014  and a second end  1016 . The device  1000  also has second and third arms  1018   a,b  which each have a respective first end  1020   a,b  and a respective second end  1022   a,b  (see also  FIG. 10 ). Also shown in  FIG. 9 , arms  1018   a,b  each have a respective handle  1024   a,b  that is attached to a respective second end  1022   a,b . In a typical embodiment of the device  1000 , the handle  1024  is free to rotate about axis  1134  using an attachment well know to those skilled in the pertinent art. Additionally, the first arm  1012  and arms  1018   a,b  each have a respective lockingpin  1026   a–c  that can be manipulated in a manner well known in the art to telescopically adjust the respective lengths of the arms  1012 ,  1018   a  and  1018   b.    
     FIG. 9  also shows that the device  1000  includes a joint assembly  1028  which, for reference purposes, defines an axis of rotation  1030 . In their relationship to this axis of rotation  1030 , the first arm  1012  is attached to the joint assembly  1028  to establish a fixed relationship between the first arm  1012  and the axis of rotation  1030 . On the other hand, the arms  1018   a,b  are pivotally attached to the joint assembly  1028  for a reciprocal rotation of the arms  1018   a,b  about the axis of rotation  1030 . More specifically, this rotation of the arms  1018   a,b  about the axis of rotation  1030  can be in either a clockwise direction  1032  or in a counterclockwise direction  1034 . It is to be appreciated that the arms  1018   a,b  as shown in  FIG. 9  can be rotated to other positions about the axis of rotation  1030  to establish alternate exercise configurations of the device  1000 . 
     FIG. 9  further shows that the device  1000  includes a base member, which for the embodiment shown in  FIG. 9  is a frame  1145 , the construction of which is well known in the pertinent art. As shown, the frame  1145  can be attached to the second end  1016  of the first arm  1012  such that the first arm  1012  can rotate about axis  1138 . Extension member  1150  extends from frame  1145  and is attached to bracket  1156  with bolt  1152  in slot  1154  of bracket  1156 . Bracket  1156  is attached to first arm  1012  by means such as welding. Extension member  1150  has a locking pin  1151  that can be manipulated in a manner well know in the art to telescopically adjust the length of extension member  1150 . Bolt  1152  is free to slide in slot  1154  of bracket  1156  when the length of extension member  1150  is adjusted, thus allowing first arm  1012  to rotate about axis  1138 . In a typical embodiment, locking pin  1153  can be removed to allow the joint assembly  1028  to be rotated about axis  1136  to change the orientation of the joint assembly  1028  relative to first arm  1012 . Locking pin  1153  is then reinserted to lock the joint assembly  1028  in position. 
     FIG. 9  further shows that a position sensor  1038  can be mounted on the device  1000 , possibly at the joint assembly  1028 , to generate signals that are representative of the relative positions of the first arm  1012  and the arms  1018   a,b  of the device  1000 . Specifically, these signals can be generated in a manner well known in the pertinent art and transmitted to a remote computer (such as the computer  42  shown in  FIG. 1 ) or other electronic monitoring device for processing. More specifically, the signals can be used to indicate the position of the first arm  1012  relative to the arms  1018   a,b , and to measure the time duration between changes in the relative positions of said first arm  1012  and the arms  1018   a,b  of the device  1000 . It is further envisioned that a load sensor  1106 , such as a strain gauge, can be mounted on the device  1000 , possibly near handle  1024   a , to generate signals that are representative of the loads that are applied to the handle  1024   a  of device  1000 . These signals also can be generated in a manner well known in the pertinent art and transmitted to a remote computer or other electronic monitoring device for processing and displaying useful information regarding exercise sessions. Thus, exercise repetitions, the duration of each repetition, and the load applied by the user during each repetition in an exercise routine can be monitored. Furthermore, other exercise performance information and data can be determined from the signals. 
   Turning now to  FIG. 10 , the resistance mechanism that is incorporated into the joint assembly  1028  of the device  1000  is shown in detail. There it can be seen that the arms  1018   a,b  are each connected to a respective tube  1044   a,b  by means, such as welding, and that the tubes  1044   a,b  are connected to a shaft  1048  by means, such as the respective pins  1050   a,b . As shown, the shaft  1048  is centered on the axis of rotation  1030 . Further, the resistance mechanism includes a circular one-way clutch  1052 , of a type well known in the pertinent art. The one-way clutch  1052  may also have an integral bearing assembly. Those of ordinary skill in the art will understand, however, that the one-way clutch  1052  may comprise a variety of suitable devices. The one-way clutch  1052  is also centered on the axis of rotation  1030 . 
   A cone member  1056  is included in the joint assembly  1028  and is positioned against the one-way clutch  1052 . As further shown for the device  1000 , the cone member  1056  is formed with a tapered surface  1058  that surrounds the axis of rotation  1030  and is angled relative to the axis of rotation  1030  at angle, φ, which is preferably between ten and fifteen degrees. However, those of ordinary skill in the art will understand that there are many suitable values for angle φ including ninety degrees, in which case tapered surface  1058  will be substantially perpendicular to the axis of rotation  1030 . Additionally, the cone member  1056  includes a rim  1060  that is oriented radially on the axis of rotation  1030 . Also included in the joint assembly  1028  is a cup member  1062  which has a tapered surface  1064 . As shown, the tapered surface  1064  of the cup member  1062  is dimensioned to mate with the tapered surface  1058  of the cone member  1056 . As intended for the device  1000 , a friction liner  1068  is positioned between the respective tapered surfaces  1058  and  1064  of the cone member  1056  and the cup member  1062 . Preferably, the friction liner  1068  is fixed to either the cone member  1056  or the cup member  1062 . Also, the cup member  1062  is formed with a space  1054 . 
   Still referring to  FIG. 10 , it is seen that the joint assembly  1028  includes a lever  1072  that is connected to a disc  1074  by means such as the screws  1076   a  and  1076   b  ( FIG. 11 ). Disc  1074  is attached directly to threaded extension  1080  by means such as welding or other means well know to those in the art. Alternatively, disc  1074  and threaded extension  1080  can be formed as one part. Further, the threaded extension  1080  is threadably engaged with a plate  1140 . Plate  1140  is attached to cup member  1062  by screws  1148   a ,  1148   b ,  1148   c ,  1148   d ,  1148   e  and  1148   f  ( FIG. 11 ). Further, bracket  1140  is attached to the cup member  1062  and plate  1140  by screws  1144   a  and  1144   b  ( FIG. 11 ) and to cup member  1062  by screws  1146   a  and  1146   b  ( FIG. 12 ). Post  1142  is attached to bracket  1140  by means such as welding. Post  1142  is attached to arm  1012  by means such as pin  1153 . In a typical embodiment, post  1142  can rotate within first arm  1012 , about axis  1136 , and be removed from first arm  1012  by first removing pin  1153  from hole  1147  in post  1142  and hole  1149  in first arm  1012 . 
   Additionally, the joint assembly  1028  includes an adjustable force transfer mechanism. The adjustable force transfer mechanism includes a spring  1082  and a thrust bearing  1110  that are positioned between the end of threaded extension  1080  and the rim  1060  of cone member  1056 . The relative position of spring  1082  and thrust bearing  1110  is interchangeable. Preferably, spring  1082  is a belleville washer and thrust bearing  1110  is a thrust ball and cage assembly and two thrust washers. However, those of ordinary skill in the art will understand the spring  1082  and the thrust bearing  1110  may comprise a variety of suitable devices. An optional housing member  1180  is shown in phantom. 
   Turning to  FIG. 13 , it can be seen that the lever  1072  is formed with slots  1160   a  and  1160   b  and hole  1168 . Further, disc  1074  is formed with a plurality of threaded holes  1164   a ,  1164   b ,  1164   c ,  1164   d  and  1164   e  and a raised annular flange  1170 . Hole  1168  in lever  1072  and annular flange  1170  on disc  1074  are dimensioned to allow guided rotation of lever  1072  about annular flange  1170  on disc  1074 . When lever  1072  is positioned on disc  1074 , regardless of the orientation of lever  1072  about axis of rotation  1030 , at least one of the threaded holes  1164  will be exposed in each of slots  1160   a  and  1160   b . Screw  1076   a  is inserted through slot  1160   a  in lever  1072  and threaded into the exposed hole  1164  in disc  1074 . Likewise, screw  1076   b  is inserted through slot  1160   b  in arm  1072  and threaded into the exposed hole  1164  in disc  1074 . During the assembly of joint assembly  1028 , threaded extension  1080  can be threaded into plate  1140  to any depth desired and then arm  1072  can be assembled to disc  1074  at any radial position about axis of rotation  1030 . This assembly procedure provides a means for calibrating the joint assembly  1028 . Preferably, disc  1074  has five threaded holes,  1164   a ,  1164   b ,  1164   c ,  1164   d  and  1164   e , equally spaced circumferentially about annular flange  1170 . Lever  1072  has two slots,  1160   a  and  1160   b , each extending approximately 72° circumferentially about hole  1168  and spaced apart approximately 72° circumferentially about hole  1168 . However, those of ordinary skill in the art will understand that there are many configurations and combinations of slots  1160  in arm  1072  and threaded holes  1164  in disc  1074  that are suitable. 
   In the operation of the device  1000 , a user  1090  will first adjust the exercise resistance that is to be provided by the joint assembly  1028 . Specifically, this is accomplished by rotating the lever  1072 . With reference to  FIG. 10 , it will be appreciated by a skilled artisan that a rotation of the lever  1072  causes the threaded extension  1080  to interact with the plate  1140  in a way that will effect a translational movement of the threaded extension  1080 . Accordingly, depending on the direction that lever  1072  is rotated, the threaded extension  1080  will either advance into the space  1054  or be withdrawn from the space  1054 . The consequence of this is that the adjustable force transfer mechanism (which in this case includes spring  1082 ) will be respectively relaxed or compressed between the end of the threaded extension  1080  and the rim  1060  of cone member  1056 . In either case, the force that is generated by the spring  1082  will act against the cone member  1056 . Importantly, this force will be effectively transferred through the cone member  1056  to establish a reactive force on the friction liner  1068  at the interface between the tapered surface  1058  of the cone member  1056  and the tapered surface  1064  of the cup member  1062 . Furthermore, utilizing an adjustable force transfer mechanism allows the lever  1072  to be rotated through larger angles in adjusting the exercise resistance from its lowest setting to its highest setting than would be possible if an adjustable force transfer mechanism was not employed. 
   Through the action of the one-way clutch  1052 , the arms  1018   a,b  are able to freely rotate about the axis of rotation  1030  when the arms  1018   a,b  are rotated in a predetermined direction, e.g. the clockwise direction  1032 . On the other hand, the one-way clutch  1052  will fixedly engage the arms  1018   a,b  with the cone member  1056  when the arms  1018   a,b  are rotated in the opposite direction, e.g. the counterclockwise direction  1034 . As a consequence, when the arms  1018   a,b  are fixedly engaged with the cone member  1056  through the one-way clutch  1052 , the rotation of the arms  1018   a,b  will encounter the resistance that is established on the friction liner  1068  between the cone member  1056  and the cup member  1062 . As indicated above, the amount of this resistance is established by rotating the lever  1072 . Through the action of thrust bearing  1110 , the threaded extension  1080 , disc  1074  and lever  1072  are prevented from rotating when the action of the one-way clutch  1052  causes cone  1056  to rotate with respect to cup  1062  as arms  1018   a,b  are rotated. Further, a visible gauge (not shown), can be used for determining preferred resistance levels. 
     FIGS. 14A and 14B  show an exemplary use of the device  1000  wherein the axis of rotation  1030  is positioned to exercise the chest of user  1090 . Rotation of one or both of the handles  1024   a,b  by the user  1090  in a clockwise direction  1032  ( FIG. 14A ) will be met by a resistance force generated by the joint assembly  1028  as the arms  1018   a,b  are rotated about the axis of rotation  1030 . Conversely, rotation of the handles  1024   a,b  by the user  1090  in a counterclockwise direction  1034  ( FIG. 14B ) will meet no resistance from the joint assembly  1028  as the arms  1018   a,b  are rotated about the axis of rotation  1030 . Further, the direction in which the resistance force acts can be reversed by first removing pin  1153  ( FIG. 9 ), rotating the joint assembly  1028  approximately one hundred and eighty degrees about axis  1136  ( FIG. 9 ), and reinserting pin  1153 . The arm  1012 , arms  1018   a,b  and extension member  1150  can be lengthened or shortened to effect other exercises. 
     FIGS. 15A and 15B  show a use of the device  1000  for exercising the lower body of user  1090  wherein the joint assembly  1028  is oriented such that rotation of the handles  1024   a,b  by the user  1090  in a counterclockwise direction  1034  ( FIG. 15A ) will be met by a resistance force generated by the joint assembly  1028  as the arms  1018   a,b  are rotated about the axis of rotation  1030 . Conversely, rotation of the handles  1024   a,b  by the user  1090  in a clockwise direction  1032  ( FIG. 15B ) will be meet with no resistance from the joint assembly  1028  as the arms  1018   a,b  are rotated about the axis of rotation  1030 . 
     FIGS. 16A and 16B  show a use of the device  1000  for exercising the gluteus maximus muscle of the user  1090  wherein the user  1090  is in a standing position. The joint assembly  1028  is oriented such that rotation of the handles  1024   a,b  by the user  1090  in a clockwise direction  1032  ( FIG. 16A ) will be met by a resistance force generated by the joint assembly  1028  as the arms  1018   a,b  are rotated about the axis of rotation  1030 . Conversely, rotation of the handles  1024   a,b  by the user  1090  in a counterclockwise direction  1034  ( FIG. 16B ) will be meet with no resistance from the joint assembly  1028  as the arms  1018   a,b  are rotated about the axis of rotation  1030 . 
   Regardless which embodiment of the device  1000  is contemplated, the position sensor  1038  can be used to monitor or guide the exercise routine of the user  1090 . For example, in addition to signals containing time information data, the signals can also convey information about the relative positions of the first arm  1012  and arms  1018   a,b  of the device  1000 . Thus, returning to  FIGS. 14A and 14B , the signals can include information on the angle a between the arm  1012  and arms  1018   a,b  ( FIG. 14A ), and changes in this angle α to the angle α′ ( FIG. 14B ). Furthermore, the load sensor  1106 , either in combination with the position sensor  1038  or alone, can be used with any of the embodiments of the device  1000  to monitor or guide the exercise routine of the user  1090 . The signals can also contain data regarding the magnitude of the force applied by the user  1090  to the device  1000  to overcome the resistance force generated by the joint assembly  1028  as the arms  1018   a,b  are rotated from a position at angle α from arm  1012  ( FIG. 14A ) to a position at angle α′ from arm  1012  ( FIG. 14B ). Additionally, the signals can contain data regarding the magnitude and relative direction of the force applied by the user  1090  of the device  1000  in returning the arms  1018   a,b  from angle α′ to angle α. Such information and data, of course, can be useful for monitoring both the duration and the extent of exercise routines conducted with the device  1000  as well as the magnitude of the loads applied to the device  1000  by the user  1090  during the exercise routines. This information and data can also be used by a computer or other electronic monitoring devices to perform calculations and analysis of the exercise routines. 
   While the particular exercise device with true pivot point as herein shown and disclosed in detail is fully capable of obtaining the objects and providing the advantages herein before stated, it is to be understood that it is merely illustrative of the presently preferred embodiments of the invention and that no limitations are intended to the details of construction or design herein shown other than as described in the appended claims.