a preferred embodiment linkage arrangement constructed according to the principles of the present invention is designated as 100 in fig1 - 7 . the linkage arrangement 100 is shown on a preferred embodiment exercise apparatus 200 , which may be described as an elliptical motion exercise machine that is otherwise similar to an exercise machine disclosed in u . s . pat . no . 5 , 895 , 339 ( which is incorporated herein by reference ). however , the present invention is not limited to this specific type of exercise machine , nor to any particular category of exercise machine , but rather , is suitable for use on various sorts of exercise equipment . examples of other suitable applications are mentioned above with reference to other patents that have been incorporated herein by reference . both the linkage arrangement 100 and the exercise apparatus 200 are generally symmetrical about a centrally located , vertical plane , with the primary exception being the relative orientation of components disposed on opposite sides of the plane of symmetry . generally speaking , the “ right - hand ” components are one hundred and eighty degrees out of phase relative to the “ left - hand ” components . in any event , like reference numerals are used to designate both the “ right - hand ” and “ left - hand ” parts , and when reference is made to one or more parts on only one side of an apparatus , it is to be understood that corresponding part ( s ) are disposed on the opposite side of the apparatus . also , parts that are intersected by the plane of symmetry exist individually and thus , do not have any “ opposite side ” counterparts . moreover , to the extent that reference is made to forward or rearward portions , it is to be understood that a person could exercise while facing in either direction . the linkage arrangement 100 may be described with reference to a leg member 120 and a handlebar 130 . on the preferred embodiment 100 , the leg member 120 is a rocker link that is pivotally connected to frame member 110 at pivot axis pa ( shown in fig2 ), and the handlebar 130 is a rocker link that is pivotally connected to frame member 110 at pivot axis pb ( shown in fig2 ). a distal end 133 of the handlebar 130 , opposite the pivot axis pb , is sized and configured for grasping . a base 112 supports the frame member 110 in a stationary , generally vertical orientation relative to an underlying floor surface . the leg member 120 may be described in terms of upper and lower portions that extend radially away from the leg pivot axis pa . as more fully explained in u . s . pat . no . 5 , 895 , 339 , a distal end of the lower portion is pivotally connected to a forward end of a respective foot supporting link 220 . an opposite , rearward end of each foot supporting link 220 is pivotally connected to the upper end of a respective connector link 230 . an opposite lower end of each connector link 230 is pivotally connected to a respective rocker link 240 , which in turn , is pivotally connected to the base 112 . an intermediate portion of each connector link 230 is pivotally connected to a respective crank 250 , which in turn , is rotatably mounted on the base 112 . as a result of this arrangement , an intermediate portion of each foot supporting link 220 moves through a generally elliptical path as each crank 250 rotates and each leg member 120 pivots back and forth . a flywheel 260 is secured to the crank shaft and constrained to rotate together with the cranks 250 . the flywheel 260 adds inertia to the linkage assembly , and any known flywheel resistance mechanism may be connected to the flywheel 260 to add resistance , as well . for example , a drag strap may be disposed about the circumference of the flywheel 260 and maintained in tension as shown in u . s . pat . no . 4 , 023 , 795 , which is incorporated herein by reference . other suitable resistance mechanisms include known electrical braking arrangements and other known types of mechanical braking arrangements . those skilled in the art will also recognize that the flywheel 260 could be replaced by a relatively large diameter pulley which is linked to a remote flywheel by means of a relatively small diameter pulley . a channel or race 123 extends lengthwise along at least the upper portion and intermediate portion of the leg member 120 . a roller 132 is rotatably mounted on an intermediate portion of the handlebar 130 , and is disposed inside the race 123 . the leg member 120 is connected to the frame member 110 in a manner that does not obstruct the race 123 . the roller 132 and the race 123 cooperate to constrain the intermediate portion of the handlebar 130 to movement along the leg member 120 . on the linkage arrangement 100 , the diameter of the roller 132 is slightly smaller than the width of the race 123 , so that the roller 132 bears against only one side of the race 123 at any given time . other arrangements may be provided in lieu of the “ play ” or “ slop ” between the roller 132 and the race 123 . for example , the roller may be coated with a resilient material having a low friction surface in contact with each side of the race 123 . in the alternative , the inside of the race 123 may be lined with a resilient material having opposing , low friction surfaces in contact with the roller 132 . yet another option is to replace the roller 132 with a low friction slide block . [ 0024 ] fig8 shows another alternative arrangement suitable for interconnecting the handlebar 130 and the leg member 120 . a substitute leg member 120 ′ is provided with a race 123 ′ having a first track ( associated with offset 122 ′) and a second track ( associated with offset 124 ′). a shaft 131 ′ is secured to the handlebar 130 and defines a roller axis ra ′. a first roller 132 ′ is rotatably mounted on the shaft 131 ′ and bears against the offset 122 ′ associated with the first track . a second roller 134 ′ is rotatably mounted on the shaft 131 ′ and bears against the offset 124 ′ associated with the second track . this arrangement maintains positive , driving contact between the leg member 120 ′ and the handlebar 130 in all phases of operation . the offsets 122 ′ and 124 ′ and the rollers 132 ′ and 134 ′ are shown with complementary convex and concave profiles that may be considered desirable for purposes of maintaining axial alignment . in the absence of such profiles , axial alignment may nonetheless be ensured in various ways , including sufficiently sturdy bearings at the pivot axis pb . with reference back to fig2 a respective roller 132 is provided on each side of the linkage arrangement 100 , and rotates about a respective roller axis ra . in fig2 each roller 132 is disposed in the upper portion of a respective leg member 120 , at a distance from the leg pivot axis pa . as a result , pivoting of each leg member 120 about the common pivot axis pa is linked to pivoting of a respective roller 132 , as well as the remainder of the respective handlebar 130 , about the common pivot axis pb . the extent or magnitude of the handlebar pivoting is a function of the distance between the roller axes ra and the pivot axis pa . for example , fig4 shows the roller axes ra at a maximum distance from the pivot axis pa , and the handles 133 at relatively distant extreme positions ; fig5 shows the roller axes ra relatively nearer to the pivot axis pa , and the handles 133 at more moderate extreme positions ; and fig6 shows the roller axes ra in alignment with the pivot axis pa , and the handles 133 in a common , stationary position . in fig6 the leg members 120 do not impart any “ driving ” force against respective rollers 132 , because the leg members 120 are pivoting about the roller axes ra . some people may prefer that the handles 133 always move at least a small amount to ( a ) entice the user to begin arm exercise ; and / or ( b ) convey to the user that the handles 133 are movable . in order to facilitate adjustment of the roller axes ra relative to the pivot axis pa , the handlebar pivot axis pb is selectively movable relative to the frame member 110 . in particular , a brace 140 has a first end pivotally connected to the frame member 110 , and an opposite , second end that pivotally supports the handlebars 130 ( and is intersected by the pivot axis pb ). also , an adjustable length member 150 has a first end pivotally connected to the frame member 110 , and an opposite , second end that is pivotally connected to the second end of the brace 140 ( and similarly intersected by the pivot axis pb ). on the preferred embodiment 100 , the member 150 is a linear actuator that changes length to adjust the position of the pivot axis pb , as well as the position of the roller axes ra . for example , fig4 shows the member 150 in a retracted , relatively short configuration , and fig6 shows the member 150 in an extended , relatively long configuration . the operation of the leg exercising portion of the machine 200 is the same regardless of how the handlebars 130 are set , and the stroke length of the handlebars 130 may be adjusted without any disruption of the leg exercise activity . also , the linkage arrangement 100 is such that each leg member 120 and respective handlebar 130 remain synchronized regardless of the latter &# 39 ; s range of motion . on the embodiment 100 , each handlebar 130 pivots in the same direction as its respective leg member 120 . however , those skilled in the art will recognize that each handlebar 130 may be arranged to pivot in an opposite direction relative to its respective leg member 120 ( by moving the roller axis ra beneath the pivot axis pa , for example ). yet another feature of the preferred embodiment 200 is that handles 133 move downward as their stroke length decreases ( see fig6 ), and they move upward as their stroke length increases ( see fig4 ). this “ translational effect ” gives the handles 133 a somewhat magical or “ high tech ” quality from the perspective of the user . it also lends itself to various design options and alternative applications . for example , some people may consider it preferable to design the arrangement 100 so that the handles 133 move forward , additionally or alternatively , as their stroke length decreases . a user interface or console 190 is mounted on top of the frame member 110 . the interface 190 may be configured to perform a variety of functions , including ( 1 ) displaying information to the user , including ( a ) exercise parameters and / or programs , ( b ) the current parameters and / or currently selected program , ( c ) the current time , ( d ) the elapsed exercise time , ( e ) the current speed of exercise , ( f ) the average speed of exercise , ( g ) the number of calories burned during exercise , ( h ) the simulated distance traveled during exercise , ( i ) material transmitted over the internet , and / or ( j ) amounts of work currently being performed by the user &# 39 ; s arms and / or legs ; and / or ( 2 ) allowing the user to ( a ) select or change the information being viewed , ( b ) select or change an exercise program , ( c ) adjust the resistance to exercise ( of the arms and / or the legs ), ( d ) adjust the stroke length ( of the arms and / or the legs ), ( e ) adjust the orientation of the exercise motion , and / or ( f ) quickly stop the exercise motion ( of the arms and / or the legs ). the linear actuator 150 may be considered desirable because it facilitates automatic and / or remote adjustments to the handlebar stroke length . for example , control signals may be generated by ( a ) the user pushing a button on the user interface 190 ; ( b ) a sensor detecting the presence or absence of the user &# 39 ; s hands on the handles 133 ; ( c ) a sensor detecting that the user &# 39 ; s level of exertion is outside a target range ; ( d ) an automated program ; and / or ( e ) a person other than the user ( such as a trainer ) who is in communication with the apparatus . on alternative embodiments , the linear actuator 150 may be replaced by other suitable devices . for example , a pneumatic cylinder may be substituted for the linear actuator 150 , and connected to a remote compressor . another possible alternative is to insert a pin through a hole in a cylinder and any of several “ alignable ” holes in a rod that telescopes inside the cylinder . on other embodiments , the adjustable length member could be eliminated , and the brace 140 could be adjusted in more direct fashion . in any event , adjustments may be driven by a power supply , performed manually , or performed using work generated during exercise activity . for example , the flywheel 260 and / or the leg members 120 may be tapped to provide the necessary energy . the interface 190 may be programmed to perform a variety of functions and / or provide a variety of options regarding the linkage arrangement 100 . for example , a user may push a button to maintain a desired range of motion for the handlebars 130 . the interface 190 may be programmed to maintain the range of motion , but to stop the handlebars 130 in response to a signal from the user or upon detecting that the user has removed his hands from the handles 133 . the interface 190 may then resume the desired range of handlebar motion in response to another signal from the user or upon detecting a return of the user &# 39 ; s hands to the handles 133 . the handles 133 may be configured to sense arm exertion , via force sensors , for example , in which case the interface 190 may also be programmed to alert the user if arm exercise falls below a target level . the present invention also allows the user to simply “ turn off ” the arms to ( a ) facilitate the performance of a secondary task , such as reading a book , taking a drink , or interacting with a computer and / or internet terminal ; and / or ( b ) focus only on lower body exercise , for example . the present invention also provides various methods which may be implemented in accordance with the embodiments discussed above . recognizing that this disclosure will enable persons skilled in the art to recognize various embodiments , modifications , and / or applications , the scope of the present invention is to be limited only to the extent of the claims which follow .
an exercise apparatus includes a frame , a leg driven member pivotally mounted on the frame , and a handlebar pivotally mounted on the frame and movably connected to the leg driven member . the point of interconnection between the handlebar and the leg driven member is adjustable relative to the pivot axis of the leg driven member . adjustment toward the pivot axis causes the handlebar stroke to decrease , and conversely , adjustment away from the pivot axis causes the handlebar stroke to increase .