Abstract:
A recumbent step exercise machine including a frame, a seat supported from the frame, and a drive mechanism supported from the frame. The drive mechanism includes a first and a second pedal, at least one axle shaft, at least one clutch, a speed increaser, and a brake. The first and the second pedal assemblies are each linked to at least one shaft by a linkage assembly. Each of the shafts are drivingly engaged to at least one clutch. The linkage assemblies act as levers that translate the reciprocating motion of the pedal assemblies into rotational motion of the shaft. Each linkage assembly extends downwardly from the shaft to which it is drivingly engaged and terminates with the pedal assembly. A first and a second arm mechanism may be linked through the linkage assembly to the first and second pedal assembly.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims the benefit of U.S. Provisional Application Ser. No. 60/509,979 filed on Oct. 8, 2003. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates generally to exercise equipment. More specifically, the present invention relates to the field of stair climbing, or stepper, exercise machines. 
     2. Background of the Invention 
     Many different designs of equipment exist for the purpose of physical exercise and physical therapy. One such type, stair climbing machines, or steppers, simulate climbing stairs or steps. With such machine designs know in the industry, the user typically places his or her feet on a pair of pedals and begins to alternately raise his or her legs as if he or she were climbing a flight of stairs. The pedals respond by raising and applying a load resistance which the user must overcome to lower the pedal. The amount of resistance is determined by the weight and/or fitness level of the user. Steppers are known to provide a superior low impact workout for therapy, rehabilitation or cardiovascular conditioning for the amount of time spent by the user on the machine. 
     One problem with stair climbing machines known in the art is that such steppers require the user to be standing in order to operate the machines. This limitation restricts usage to those who are physically capable of standing during exercise and are thus less than optimal for physical therapy and rehabilitation use. A need, therefore exists for a stepper type exercise device which can be operated in a seated position by those who are unable to stand. 
     Alternatively, people who are less fit have been know to find stair climbing machines to be too difficult to operate for extended periods of time. In such cases, workouts tend to be shortened, thereby also reducing the aerobic benefit of the workout. A need, therefore, also exists for a stepper type exercise device which allows users who are less physically fit to achieve a sustained cardiovascular workout. 
     A related limitation is that since the user is in a standing position, the user can effectively use his or her body weight alone to overcome the resistance required to lower the pedal. In this manner, the aerobic benefit of the workout is reduced. As a result, a need exists for a stepper type exercise device which is not responsive to the weight of the user. 
     SUMMARY OF THE INVENTION 
     The recumbent step exercise machine of the present invention includes, generally, a frame, a seat supported from the frame, and a drive mechanism supported from the frame. The drive mechanism includes a first and a second pedal, at least one axle shaft, at least one clutch, a speed increaser, and a brake. 
     The first and the second pedal assemblies are each linked to at least one shaft by a linkage assembly. Each of the shafts are drivingly engaged to at least one clutch, each of which is, in turn, in driving engagement with the brake. 
     The pedal assemblies include a footbed to receive the foot of the person operating the machine and a platform to which it is affixed. The platform is pivotally attached to the linkage assembly. 
     The linkage assemblies are essentially levers which translate the reciprocating motion of the pedal assemblies into rotational motion of the shaft. Each linkage assembly extends downwardly from the shaft to which it is drivingly engaged and terminates with the pedal assembly. This allows the working mechanism of the machine, the drive mechanism, to be substantially upright supported by the frame, to allow step-through space between the seat and the housing enclosing the drive mechanism. 
     In operation, the pedal assemblies are activated by a person seated in the seat in a manner known in the industry to be recumbent. Reciprocation of the pedal assemblies rotate, or drive, a shaft through the linkage assembly. There could be a single shaft or a shaft driven by each pedal assembly. The clutch, or clutches in the case of multiple shafts, sum the driving rotational motion derived from reciprocation of each pedal assembly which is drivingly engaged with the speed increaser. 
     The speed increaser acts to increase the speed of driving rotation obtained from activation of the pedal assemblies and is drivingly engaged with the brake. The brake, in turn provides resistance to the drive mechanism to vary the intensity of the workout for the user of the machine. 
     The recumbent configuration of the present invention allows for accurate measure of the amount of work performed by the person using the machine. This is because the body weight of the person rests on the seat and not the pedals. 
     A first and a second arm mechanism may be linked, preferably through the linkage assembly, to the first and second pedal assembly, respectively, in an alternate embodiment. In this embodiment, the arm mechanisms combine sum with the pedal assemblies to drive the speed increaser. 
     A display of the type known in the industry is electrically connected to the brake and receives raw data from the brake. The display then computes and provides certain information to the user in a known manner. The brake provides the electrical energy required to operate the display. 
     It is an object of the present invention to provide a recumbent step exercise machine which provides a low impact aerobic workout for therapy, rehab, or cardiovascular conditioning. It is still a further object of the present invention to provide such a recumbent step exercise machine which may also arm mechanisms to provide an upper body workout. 
     It is a further object of the present invention to provide a recumbent step exercise machine which translates energy expended through reciprocation to electrical energy and/or resistance energy. 
     A yet further object of the present invention is to provide a recumbent step exercise machine which translates such motion through the use of linkage assembly which extends downward from a shaft and terminates with a pedal assembly. 
     Additional objects and advantages of the present invention will become apparent to those skilled in the art to which this invention relates from the accompanying drawings taken in conjunction with the following detailed description of the preferred embodiment and the claims. 
     Thus, the present invention is well adapted to carry out the objects and attain the ends and advantages mentioned above as well as those inherent therein. While presently preferred embodiments have been described for purposes of this disclosure, numerous changes and modifications will be apparent to those skilled in the art. Such changes and modifications are encompassed within the spirit of this invention as defined by the appended claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a side view of the recumbent step exercise machine of the present invention. 
         FIG. 2  is a side view of the recumbent step exercise machine of the present invention with its external cover removed. 
         FIG. 3  is a front view of the recumbent step exercise machine of the present invention with its external cover removed. 
         FIG. 4  is a plan view of the recumbent step exercise machine of the present invention with its external cover removed. 
         FIG. 5  is a side view of the recumbent step exercise machine of the present invention taken from the side opposite  FIG. 2  with the cover removed. 
         FIG. 6  is a side view of a basic embodiment of the recumbent step exercise machine of the present invention without the arm mechanisms and the external cover removed. 
         FIG. 7  is a schematic representation depicting the path of travel of a pedal assembly of the recumbent step exercise machine of the present invention. 
         FIG. 8  is a schematic representation depicting the path of travel of a pedal assembly with an arm mechanism attached to the recumbent step exercise machine of the present invention. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Before describing the preferred embodiment of the present invention in detail, it is important to understand that the invention is not limited in its application to the details of the construction illustrated and the steps described herein. The invention is capable of other embodiments and of being practiced or carried out in a variety of ways. It is to be understood that the phraseology and terminology employed herein is for the purpose of description and not of limitation. 
     Referring now to the drawings, wherein like reference numerals indicate the same parts throughout the several views, the inventive recumbent step exerciser  10  is shown in its general environment in  FIG. 1 . In a preferred embodiment, exerciser  10  comprises: a pair of pedal assemblies  12  and  14  which are alternatingly pushed down and away from the user  16 ; a pair of arm mechanisms  18  and  20  which are pulled toward the user  16 ; a seat  22  to support the user  16  during a workout; a frame  24  which generally supports exerciser  10 ; and display unit or console  26  which allows the user  16  to select the degree of resistance applied to pedal assemblies  12  and  14  and arm mechanisms  18  and  20 , and provide feedback to the user, both in instantaneous values, i.e., METS, watts, heart rate, steps per minute, etc., and totalized values, i.e., calories, steps taken, etc. Cover  28  protects internal components of exerciser  10  from dust, sweat, and other contaminants, as well as protecting people from moving parts within exerciser  10  and providing a pleasing appearance. 
     Pedal assemblies  12  and  14  are each connected to frame  24  through a four-bar linkage assembly which controls articulation of the associated pedal over its range of motion. Turning to  FIG. 7 , four-bar linkage assembly  30  comprises: crank  32 ; lower link  34 ; pedal support  36  connected to crank  32  and link  34  at pivots  42  and  44 ; and frame  24  ( FIG. 1 ), which fixes the relative positions of pivots  38  and  40 . As will be appreciated by those skilled in the art, by judicious selection of the relative lengths of the members of four-bar linkage assembly  30 , the degree to which the angle of pedal assemblies  12  or  14  varies depends on the arc  46  traversed by pivot  42  and the arc  48  traversed by pivot  44  over the range of pedal assemblies  12  and  14 . 
     Referring next to  FIG. 8 , in a preferred embodiment the movement of arm mechanisms  18  and  20  is coordinated with the movement of pedal assemblies  12  and  14 , respectively. Arm mechanisms  18  and  20  include: bar  50 ; hand grip  52  covering bar  50  at its upper end; an aperture (not shown) through bar  50  at pivot point  54 ; and aperture  56  at the lower end of bar  50 . Link  58  ties the lower end of bar  50  to aperture  60  of crank  32  such that, as pedal  12  or  14  traverses arcs  46  and  48  in a downward and forward, crank  32  pulls link  58  to move the lower end of handle bar  18  or  20  along arc  62  in a generally forward direction. In turn, the upper end of bar  50  moves along arc  64  in a generally rearward direction. When the direction of pedal  12  or  14  reverses, the direction of movement of grip  52  likewise reverses. 
     Turning next to  FIGS. 2-5 , once a pedal  12  or  14  is pushed forward by the user, there must be a method in place to return the pedal to its initial position. Two schemes are well known in the art. First, a spring could be attached to each pedal to return the pedal for the next cycle. This type of system is referred to as an independent system since movement of one pedal is independent of the movement of the opposite pedal. 
     Alternatively, forward movement of one pedal can be used to return the other pedal to its starting position. This type of system is sometimes referred to as a dependent system because the position of one pedal is dependent on the position of the other pedal. While the present invention is well adapted to be practiced in either an independent movement or a dependent movement, the dependent system has a number of advantages in terms of the mechanics of the exercise machine relative to the user. By way of example and not limitation, a pedal return spring would return to the user a portion of the energy expended in the workout, reducing the accuracy with which the work can be measured. Further, it is well known in the art that, particularly aerobic machines in a health club setting may endure many hours of use per day. In past machines, spring breakage has been a problem under such use. 
     The pedal return mechanism of the present invention includes: pivot bar  68  pivotally attached to frame  24  at pivot  70 ; forward link  66   a  pivotally attached between left crank  32   a  and the left end of pivot bar  68 ; and forward link  66   b  pivotally attached between right crank  32   b  and the right end of pivot bar  68 . Rearward links  72   a  and  72   b  continue rearwardly from each end of pivot bar  68  to arm mechanisms  18  and  20 , respectively, to complete the link from cranks  32   a  and  32   b  to bars  18  and  20 . By way of example, as pedal  12  is pushed down, crank  32   a  acts to pull the associated forward link  66   a  forward and, in turn, the left end of pivot bar  68  forward. As a result, the right end of pivot bar  68  is pushed rearward, pulling the opposite link  66   b  and rotating the other crank  32   b  to return the pedal  14  to its initial position. Pushing pedal  14  reverses the process to return pedal  12  to its initial position. It should be noted that the machine will assume the appropriate range of motion for a particular user since the user controls the return height of one pedal by the depth to which the opposite pedal is pushed. 
     It should be noted that terms of position, such as forward, rearward, left, right, etc., are indicate position from the perspective of a user of the machine. 
     To provide resistance to the user, work performed by the user, either through pushing the pedal assemblies, or pushing and/or pulling the arm mechanisms, is converted to a continuous rotation and used to drive a brake. As discussed above, movement of pedal assemblies  12  and  14 , and/or arm mechanisms  18  and  20 , results in rotation of the corresponding cranks  32   a  and  32   b . As best seen in  FIG. 3 , crank  32   a  is clamped to axle  74   a  so that a rotation of crank  32   a  results in a like rotation of axle  74   a . Axle  74   a  is supported from frame  24  by pillow block bearings  76   a  and  76   b . In a like fashion, crank  32   b  is clamped to axle  74   b  so that rotation of crank  32   b  causes a like rotation of axle  74   b . Axle  74   b  is supported from frame  24  by bearings  76   c  and  76   d . Input sprocket  78  is rotationally supported from axles  74   a  and  74   b . A pair of overrun clutches (not shown) are housed within the hub  80  of sprocket  78 , positioned such that one clutch acts on axle  74   a  while the other clutch acts on axle  74   b . In the preferred embodiment, the clutches are oriented in hub  80  such that either clutch drives sprocket  78  in response to counterclockwise rotation (as viewed from the perspective of  FIG. 2 ) of its corresponding axle  74   a  or  74   b  and overruns in response to clockwise rotation. Thus, when user  16  pushes on a pedal  12  or  14 , sprocket  78  is driven in a counterclockwise direction. Meanwhile, the opposite pedal is pushed towards the user and the clutch acting on the associated axle overruns. Thus continuous alternating movement of the pedal assemblies by a user will result in continuous rotation of sprocket  78  in one direction. It should be noted that, in light of the dependent nature of the pedal action, both clutches could be reversed and the machine would operate identically except that sprocket  78  would rotate in the opposite direction. Overrun clutches are well known in the art. 
     Sprocket  78  drives a speed increaser which increases the rate of rotation to a speed which is suitable for braking. In the preferred embodiment, the rotational speed is increased through a combination of sprockets and chain, and belts and pulleys. A first increase in rotational speed is obtained through the driving of sprocket  84  by chain  82 , which is in turn driven by sprocket  78 . Idler  86  is spring loaded to maintain an appropriate level of tension in chain  82 . Sprocket  84  is affixed to pulley  88  such that pulley  88  rotates at the same rotational speed as sprocket  84 . A second increase in rotational speed is obtained by driving pulley  90  with belt  92 , which is in turn driven by sprocket  88 . The rotor of brake  94  is driven directly by pulley  90 . As will be apparent to those skilled in the art, the important aspect of the speed increaser is the overall ratio of input speed at sprocket  78  to the output speed at brake  94 . Many alternative methods exist for achieving a similar gain in rotational speed such as through a gear box or transmission, using more or less pairs of sprockets and chains/belts, etc. 
     Referring to  FIG. 5 , in the preferred embodiment brake  94  is a dual-acting brake in that braking force may be applied either through the generation of electrical power, and its subsequent dissipation in a load, or through eddy current braking. The present brake offers an advantage that the inventive exerciser  10  may be used in a stand-alone mode. As a stand-alone device, exerciser  10  includes a rechargeable battery (not shown). As a user begins using the machine, initially console  26  is receives electrical power from the battery. As the exerciser begins to exercise, electrical power generated by brake  94  is used to recharge the battery and to power console  26 . Under the control of console  26 , if more resistance is need than is provided by the generation of electricity for operation of the machine, the eddy current function of brake  94  is activated to increase the mechanical resistance applied by brake  94  without generating excess electricity which would have to be switched through a load resistor. A number of alternative braking means are suitable for use in the present invention, including by way of example and not limitation, an electrical generator, or alternator, in combination with a load resistor, an eddy current brake, a magnetic particle brake, a friction brake, or the like. 
     Referring now to  FIG. 6 , in a basic alternate embodiment, exerciser  100  may be configured to provide only a lower body exercise. As in the above described embodiment, exerciser  100  includes pedal assemblies  12  and  14  connected to a four-bar mechanism  30  to rotationally drive sprocket  78  in response to the user manipulating pedal assemblies  12  and  14 . Through the summing of rotational movement through overrun clutches, and an increase in rotational speed through the speed increaser, sprocket  78  drives brake  94 . Preferably the pedal assemblies of exerciser  100  are operated in a dependent manner through the interaction of crank  32   b , link  66   b , pivot bar  68  and like components located on the opposite side of exercise machine  100 . 
     With reference once again to  FIGS. 1 and 4 , it should be noted that preferably exercise machine  10  includes an adjustable seat  22  to allow user  16  to place the seat at a comfortable position relative to pedal assemblies  12  and  14 . Seat adjustment is accomplished by moving lever  96  and moving seat  22  to the desired position. Releasing lever  96  allows a pin (not shown) to index in a hole, such as hole  98 , in frame  24  to lock seat  22  at the selected position. 
     Exercise machine  10  can be moved by raising back end  102  to bring wheels  104  into contact with the floor. When in place, exerciser  10  rests on feet  106 , which are formed of rubber, or a similar material, to prevent unwanted movement of the machine during use.