Abstract:
A stroller is provided that features a frame element and at least one wheel supporting the frame, a first arm member configured to be gripped by a human hand mechanically coupled to the frame element such that the first arm member moves in a reciprocating manner with respect to the frame element, and a second arm member configured to be gripped by a human hand mechanically coupled to the frame element such that the second arm member moves in a reciprocating manner with respect to the frame element. A coupling member is provided that mechanically couples the first arm member to the second arm member such that the reciprocating movement of the first arm member is substantially maintained in opposition to the reciprocating movement of the second arm member whereby the natural periodic movement of human arms during walking or jogging is facilitated.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention relates to a stroller and more particularly to a jogging stroller that facilitates the natural periodic arm movement of the person propelling the stroller while jogging. 
     2. Description of the Related Art 
     A conventional jogging stroller is typically configured as a carriage with three wheels that enables the user to jog while pushing the stroller. However, current designs inhibit the natural arm rhythm of a runner as she/he pushes the stroller forward, because the only way to transfer force to the stroller is through the stationary push-bar style handle. Trying to propel the stroller through the stationary bar while running becomes uncomfortable; as a result the user of the stroller resorts to methods for propelling the stroller that are not safe for the child occupant and/or tries to maintain contact with the stroller in ways not recommended by the manufacturer. 
     It is well known that, during running, the limbs of the human body move in a highly synchronous and rhythmic manner. ( The Evolution of the Study of the Mechanics of Running: Relationship to Injury , McClay I., J Am Podiatry Med Assoc. 2000 March; 90 (3): 133-48). For example, at any given time during the act of running, the position of each arm is highly dependent on the position of the other. The same can be said for leg motion during running. Positional dependence of limbs while running is crucial to the human body&#39;s ability to locomote in a fluid, balanced and coordinated manner. All of the patents, patent publications, and non-patent literature cited in this Specification are hereby expressly incorporated by reference herein. 
     It is also well known that if any one of the four human limbs is prevented from its natural movement during running, then overall rhythmicity and limb coordination is not possible. Disruption of coordinated limb motion during running can result in reduced energy efficiency, deterioration of general running performance and, in some cases, an increased risk of injury to the runner. 
     There have been several past attempts to address this issue. For example U.S. Pat. No. 6,196,947 discloses a stroller having a pair of independent pivotally connected arms with handles for the user to grasp and a device to generate resistance to the arms&#39; forward pivoting motion. By overcoming the force of the resistance device, be it an elastic cord, spring, piston or bellows, the user generates a reaction force on the frame of the stroller that propels it in a forward direction. Similarly, U.S. Pat. No. 5,876,309 has a pair of independent pivoting arms also attached to resistance devices, in this case shock absorbers, and is propelled in a similar manner. U.S. Pat. No. 6,722,689 also operates with a resistance device. In this patent a coil spring is used on each arm&#39;s handle. Another device, U.S. Pat. No. 5,674,165 has independent pivotally connected arms and a friction resistance device on each arm. This device requires the user to overcome the resistance on both the forward and backward stroke of the arm and has no means for establishing an inter-dependent motion relationship between the jogger&#39;s arms. The arm paths of these prior art devices are better than the stationary bar for addressing the problem of jogging arm motion, but these devices do not address the inter-dependent motion relationship between the jogger&#39;s arms during the act of pushing the stroller. Each arm&#39;s movement is independent of the other, which means balancing the force between the jogger&#39;s arms to propel the stroller and coordinating the arms&#39; movement relative to one another is not facilitated in these devices. Such resistance devices cause the user&#39;s input energy to surge from one arm to the other. 
     As noted above, there are a number of strollers available designed to be pushed by a jogger. However, none of these devices address the positional dependence in relation to the movement of the jogger&#39;s arms during the act of pushing the stroller. As a result the jogger is required to input a force for each arm that surges from the total force necessary to push the stroller to zero. There is, therefore, a need for a jogging stroller that can accommodate the user&#39;s natural and synchronous arm motion while simultaneously distributing between both of the jogger&#39;s arms the force required to propel the stroller. 
     SUMMARY OF THE INVENTION 
     The present invention provides a jogging stroller that facilitates the natural and periodic arm movement of the person propelling the stroller while walking, jogging or running. 
     Pursuant to the present invention, a stroller is provided that features a frame element and at least one wheel supporting the frame, a first arm member configured to be gripped by a human hand mechanically coupled to the frame element such that the first arm member moves in a reciprocating manner with respect to the frame element, and a second arm member configured to be gripped by a human hand mechanically coupled to the frame element such that the second arm member moves in a reciprocating manner with respect to the frame element. A coupling member is provided that mechanically couples the first arm member to the second arm member such that the reciprocating movement of the first arm member is substantially maintained in opposition to the reciprocating movement of the second arm member whereby the natural periodic movement of human arms during walking or jogging is facilitated. 
     In an embodiment of the present invention, the first arm member and the second arm member are mechanically coupled by a coupling member that comprises at least one gear. 
     In an embodiment of the present invention, the first arm member and the second arm member are mechanically coupled by a coupling member that comprises at least one piston and fluid to move the piston. 
     In an embodiment of the present invention, the first arm member and the second arm member are electromechanically coupled. 
     In an embodiment of the present invention, the first arm member and the second arm member are mechanically coupled by a coupling member that comprises at least, one link. 
     In an embodiment of the present invention, the first arm member and the second arm member are configured such that they can be made substantially immobile with respect to the frame member for use as at least one handle. 
     In an embodiment of the present invention, the first arm member and the second arm member form a single handle. 
     In an embodiment of the present invention, the stroller comprises three wheels. 
     In an embodiment of the present invention, the first arm member and the second arm member are configured such that they can be made substantially immobile with respect to the frame member for use as at least one handle. 
     In an embodiment of the present invention, a coupling member mechanically couples the first arm member and the second arm member such that the position of the first arm member relative to the position of the second arm member can be defined with the mathematical equation:
 
 y=A  sin((2π/ B ) x )
 
 c=−y  
 
wherein, in one complete cycle of arm movement during the act of pushing the stroller, y equals the position of the left arm, c equals the position of the right arm, A equals amplitude and represents half the distance between one arm&#39;s maximum forward position and maximum back position, B equals period and represents the time to complete one cycle of arm movement and x is time.
 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a stroller according to one embodiment of the present invention in the jogging position. 
         FIG. 2  is a side view of  FIG. 1   
         FIG. 3  is a partial perspective view of the lower arm sections and motion controller. 
         FIG. 4  is a cross-sectional view taken along line A-A in  FIG. 2 . 
         FIG. 5  is a perspective view of the back side of the stroller represented in  FIG. 1 . 
         FIG. 6  is an equation of the positional relationship between arms. 
         FIG. 7  is a graph of the equations of  FIG. 6  showing the positional relationship between arms. 
         FIG. 8  is a pictogram relating the jogger&#39;s arm position to the equation of positional relationship of  FIG. 6 . 
         FIG. 9  is a perspective view of a stroller according to one embodiment using hydraulics. 
         FIG. 10  is a top view of a hydraulic system. 
         FIG. 11  is a cross-sectional view taken along line B-B in  FIG. 10 . 
         FIG. 12  is a perspective view of a stroller according to one embodiment using a linkage system. 
         FIG. 13  is schematic of an electromechanical system. 
         FIG. 14  is a perspective view of the stroller adjusted to the walking position. 
         FIG. 15  is a back view of the stroller. 
         FIG. 16  is a cross-sectional view taken along line C-C in  FIG. 15 . 
         FIG. 17  is a detailed partial perspective view of the motion controller center assembly as seen in  FIG. 3 . 
         FIG. 18  is a side view of the stroller with the arms inline with each other while in the jogging position. 
         FIG. 19  is a side view of the stroller with the arms rotated to the walking position but the handgrips still in the jogging position. 
         FIG. 20  is a detailed partial perspective view of components on the right end of the motion controller as seen in  FIG. 5 . 
     
    
    
     DETAILED DESCRIPTION 
     Turning now to the drawings in detail where like elements are indicated with like numbers in each of the several views,  FIGS. 1 and 2  illustrate jogging stroller  10  according to one embodiment of the present invention. Stroller  10  includes a frame  11  supporting a seat  12  and optional safety belts  13  to secure a passenger to the seat  12 . A wheel  14  supports the front of the frame  11  by securing the wheel&#39;s axle  15  to the frame  11  on each side of the wheel  14 . On each side and at the rear of the frame  11  are wheels  16 , each of which is axially aligned to the opposing wheel. 
     Interposed between wheels  16  is a coupling member. In an exemplary embodiment, the coupling member is motion controller  19 . The motion controller  19  is a mechanism for facilitating natural limb movement and facilitates an even distribution of force between the user&#39;s arms as required to propel the stroller. While in  FIG. 1  the motion controller is depicted adjacent the rear axle assembly, it is understood that the mechanism can be located anywhere on the jogging stroller as long as it allows force to be communicated between the user and the stroller. 
     Extending from the motion controller are force transmitting arm members  21 . Arm members  21  interact with the motion controller  19  such that the reciprocating movement of one of the arm members is maintained in substantial opposition to the reciprocating movement of the second arm member such that the natural periodic movement of human arms during walking, jogging, or running is facilitated. An example of the motion controller mechanism is depicted in  FIG. 3 . A cross-sectional view taken from line A-A in  FIG. 2  of the motion controller mechanism is shown in  FIG. 4 . 
     As seen in  FIG. 4  each rear wheel  16  has an axle  17  coupled to the wheel hub  46  with roller bearings  18 . The axles  17  of the rear wheels  16  are supported by the motion controller  19 . 
     As see clamped in  FIG. 3  and exploded in  FIG. 5  the lower end of each arm  64 ,  24  is coupled to a drive tube  23 ,  52  with a split clamp  28 . When the two clamp halves are tightened, the clamping force on the drive tubes prevents any relative axial rotation between the arms  64 ,  24  and the drive tubes  23 ,  52 . In  FIG. 4 , the drive tubes  23 ,  52  are centered on the axis of rotation of the rear wheels  16  and can pivot within the motion controller  19 . 
     As seen in  FIG. 3 , when an arm  24 ,  64  moves from front to back this movement translates to an axial rotation of a drive tube  23 ,  52 . Referencing  FIG. 4 , each drive tube  23 ,  52  has attached to its outer end a bushing  32  and attached to its inner end a bevel gear  33 . Both a bevel gear  33  and a bushing  32  are rigidly connected to each drive tube  23 ,  52  so that no relative motion between a drive tube  23 ,  52 , bevel gear  33  and bushing  32  is possible. When a drive tube  23 ,  52  turns, its bevel gear  33  and its bushing  32  turn with it. The outer end of each drive tube  23 ,  52  is supported and rotates inside a bearing  34  that is secured inside a carrier bushing  43  rigidly connected to the tube  35  that makes up the outer portion of the motion controller  19 . The bevel gear  33  on the inside end of each drive tube  23 ,  52  is supported and rotates on a pin  36  that is centered inside the motion controller  19 . The bevel gear  33  at the inside end of each drive tube  23 ,  52  is coupled to a center bevel gear  37  by way of the teeth mesh between the gears. This center bevel gear  37  is the coupling element between the two arms  21  as seen in  FIG. 5 . Referencing  FIG. 3 , by means of the center bevel gear  37  interacting with bevel gears  33  and drive tubes  23 ,  52  each arm member  64 ,  24  is maintained in opposition to the reciprocating movement of the second arm member. 
       FIG. 3  shows the relative movement of the lower right arm tube  24  and lower left arm tube  64  and their relationship to the center bevel gear  37 . In this view the lower right arm tube  24  is moving forward. This movement causes the bevel gear  33  at the end of the right arm drive tube  52  to rotate in a clock-wise direction as viewed from the right. Since the bevel gear  33  of the right drive tube  52  is meshed with the center bevel gear  37  a rotation is caused in the center bevel gear  37 . Since the center bevel gear  37  is also meshed to the bevel gear  33  of the left drive tube  23  a rotation opposite of the bevel gear  33  of the right drive tube  52  results in the bevel gear  33  of the left drive tube  23 . This opposite rotation of the left drive tube  23  translates into the lower left arm tube  64  moving in the opposite direction of the lower right arm tube  24 ; in this view, backward. Because the left arm tube  64  and right arm tube  24  are coupled together, in this case through a gear  37 , a positional dependence is established between the arms. As one arm moves the other arm moves in the opposite direction. 
     The positional dependence relationship can be approximated mathematically with the equations in  FIG. 6 :
 
 y=A  sin((2π/ B ) x )
 
 c=−y  
 
     where y is the position of the left arm, c is the position of the right arm, A is the amplitude B is the period and x is time. This equation is graphically depicted in  FIG. 7 . This FIG. shows the relative positions of the right and left arm with +A representing the arm at its maximum forward swing position and −A representing the arm at its maximum backward swing position. The quantitative value of A is determined by the range of motion developed from each individual user&#39;s limb path during walking, jogging or running. At the zero position the arms are positioned between the maximum forward and backward positions and are substantially aligned with one another as viewed from the side of the stroller. In the pictogram of  FIG. 8  the positions of +A, 0, and −A are over-laid on the form of a jogger pushing the stroller. In the first frame the jogger&#39;s left arm is at the maximum forward swing, position +A, while the right arm is at the maximum back swing, position −A. Frame two shows the left arm moving back toward the zero position and the right arm moving forward toward the zero position. In frame three both of the jogger&#39;s arms are aligned and at the zero position. Frame four shows the joggers left arm continuing to move back from the zero position toward −A, and the right arm continuing to move forward from the zero position toward +A. In frame  5 , the jogger has completed one half cycle as the left arm has reached the −A position and the right arm the +A position. The amplitude, A, is the maximum extent of travel as measured from a point of equilibrium. In this case the equilibrium is the zero position, when the arms are aligned with each other as in frame  3 . The period B is defined as the time to complete one cycle. One cycle can be defined as an arm which starts at the +A position, moves back through the zero position until it reaches the −A position and then is moved forward through the zero position until is reaches the +A position. Any device or system, which permits arm movement satisfying the above equation, is contemplated for use with the stroller of the present invention. 
     Note that while the embodiment shown in the  FIGS. 1  thru  6  relies on the use of gear mechanisms, any device or system that establishes positional dependence between the arms can be used in the stroller of the present invention. These include, but are not limited to, hydraulic devices, pneumatic devices, electromechanical devices, or any other mechanical device or system which maintains each arm member in substantial opposition to the reciprocating movement of the second arm member. For example, a piston coupled with hydraulic fluid could function as the motion controller in the stroller of the present invention. As an example  FIG. 9  shows a stroller  10  with a left cylinder  70  and right cylinder  72  each charged with either a liquid or a gas. The base end of each cylinder is connected to a supporting frame member  74  and the rod end of each cylinder is connected to the left arm tube  64  and right arm tube  24 , respectively. When an arm tube moves forward it compresses the respective cylinder and when an arm moves backward it extends its respective cylinder. The cylinders fluid chambers are connected by a base end fluid line  76  and a rod end fluid line  78  which permit fluid transfer from one cylinder to the other.  FIG. 10  is a simplified end view of the cylinders and the connecting lines. The fluid circuit cross-section of  FIG. 11  taken along line B-B of  FIG. 10  shows the rod end fluid line  78  connecting the cylinders&#39; rod end fluid volumes  80  and the base end fluid line  76  connecting the cylinders&#39; base end fluid volumes  82 . The compressibility of a liquid fluid is considered negligible, and in this application a gas pressurized to a level higher than the external forces applied to the cylinders can also act as an incompressible fluid. Therefore, the volume of the base end fluid remains constant regardless of whether there is more fluid in one cylinder or the other. This also applies to the volume of fluid occupying the rod end of the cylinders. As the rod  84  of the right cylinder  72  is compressed, fluid is forced from its base into the base of the left cylinder  70 , which forces the rod  86  of the left cylinder  70  to extend. Simultaneously, the extension of the rod  86  of the left cylinder  70  forces fluid into the rod end of the right cylinder  72 . These cylinders do not allow fluid to transfer between the rod and base ends, therefore, the base end volume of fluid  82  and the rod end volume of fluid  80  remain independent of each other and each at a constant volume. Collectively, since the fluid is considered incompressible, and the volumes are considered constant and unmixed, as one cylinder&#39;s rod is moved the other cylinders rod must move in the opposite direction an amount equal to the first. This system using an incompressible fluid acts as a motion controller and satisfies the equation of  FIG. 6 . 
     The linkage arrangement shown in  FIG. 12  is another example of a mechanical device that serves as a motion controller. In this embodiment a center structural link  88 , supported by a frame member  90 , is free to pivot about a center pin  92 . Between the left end of the structural link  88  and the left arm tube  64  is the left transfer link  94 . Between the right end of the structural link  88  and the right arm tube  24  is the right transfer link  96 . At each end of a transfer link is a ball joint  98 . As depicted by the arrows in  FIG. 12 , when the right arm tube  24  moves forward the right transfer link  96  causes a rotation of the center structural link  88 , which causes the left transfer link  94  to constrain the motion of the left arm tube  64  to be the opposite of the right arm tube  24 . This motion relationship between the left arm tube  64  and right arm tube  24  is consistent with the equation of  FIG. 6 . 
       FIG. 13  shows an embodiment of an electromechanical configuration of the motion controller. Mechanical input from the left drive tube  23  and the right drive tube  52  feeds into separate electrical motor-regenerative brake modules  100 . These motor-brake modules  100  are energized from a power source  102 , which also has electrical storage capability i.e. a battery. The positions of the left and right drive tubes  23 ,  52  are monitored by sensors  104 , which send information to a microprocessor  106 . The microprocessor  106  uses this positional information to control the motor-brake units  100 . When an arm is sensed to be moving forward the microprocessor  106  instructs the motor-brake unit  100  to act as a regenerative brake. As the jogger applies force with one arm to overcome the brake, the reaction is for the stroller to move forward while the brake unit sends a charge to the battery. Simultaneously, the opposite motor brake unit  100  is energized to act as a motor and drives in a direction as to provide an equal force to the jogger&#39;s other arm. The microprocessor toggles each motor brake unit  100  back and forth between a motor and a brake depending on the signal received from the sensors  104  monitoring the position and direction of travel of the drive tubes  23 ,  52 . The microprocessor also regulates how strong the regenerative brake will be and balances that with the force applied by the opposite motor so that the force on the jogger&#39;s arms remains nearly equal and in the proper position relative to the other. 
       FIG. 5  shows the motion controller  19  attached to the stroller frame  11  with a supporting member  20  from each side of the frame  11 . At the upper end of each arm  21  is a handgrip  22 , which the jogger uses to grasp the arms  21 . Each arm  21  is made up of sections of telescoping type tubing. Using the left arm as an example, the lower section of tube  64  is coupled to the drive tube  23  with a split clamp, a top half  29  and a lower half  28 . The opposite end of the lower tube section  64  is connected to the second section of tube  25  with a fitting  26 . The fitting  26  is loosened to allow the second section  25  of tube to slide axially up or down within the lower section of tube  64 . This movement is used to adjust the overall height of the handgrip  22  area up or down relative to the ground. The second section of tubing  25  is connected on its top end to the upper section of tubing  27  with another fitting  26 . The second section of tubing  25  is bent toward the back of the stroller so when the upper section of tubing  27  is slid in or out of the second section of tubing  25  the handgrip  22  area moves toward or away from the stroller, respectively. The upper section of tubing  27  is also free to rotate axially within the second section of tubing  25 . This allows the user to adjust the hand grip area  22  from a jogging position as seen in  FIG. 1  to a traditional walking position as seen in  FIG. 14 . Note that the preceding description is a preferred embodiment for the arms of stroller of the present invention. The stroller arms can be configured from a single piece of material or in multiple sections as described above. Further, the stroller arms can be straight or bent depending upon the desired ergonomic effect. 
       FIG. 15  is a rear view of the stroller  10 .  FIG. 16  shows a cross-section view of the motion controller  19  from line C-C of  FIG. 15 . The pin  36  supporting the bevel gear  33  on each end of the drive tubes is rigidly attached with a roll pin  108  to a center pin  44 , which is the support for the center bevel gear  37 .  FIG. 4  shows the center pin  44  is attached to a center disk  38  with bolts  47 .  FIG. 16  shows that the center disk  38  locates itself inside a motion controller housing  35  by having an outside diameter slightly smaller than the inside diameter of the motion controller housing  35 . The center disk  38  is located axially inside the housing  35  with the threaded stud  39  of the adjustment handle  40 , which enters from the outside through a slot in housing  35  and through a hole in the center disk  38 . This threaded stud  39  threads into the end of the center pin  44  opposite the center bevel gear  37 .  FIG. 17 , a detailed view of components on  FIG. 3 , shows the center pivot assembly  45  which includes the pin  36 , center pin  44 , center bevel gear  37 , handle  40 , and center disk  38 . 
       FIG. 18  shows the stroller with the arms  21  in the jogging position. The arms  21  are in line with each other.  FIG. 19  shows the stroller with the arms  21  rotated forward to the optional walking position. (Note, however, that a user may choose to walk with the stroller in the moving arm position.) In the walking position the arms  21  are coupled to the frame with clamps  41 . Due to the positional interdependence, to move between the jogging and walking positions, the center pivot assembly  45  from  FIG. 17  (detailed from  FIG. 3 ) and the arms  21  must all rotate together. To rotate the center pivot assembly  45  and the arms  21  the handle  40  in  FIG. 15  and  FIG. 16  is turned to loosen the threaded stud  39  ( FIG. 16 ) to reduce the clamping force between the housing  35  and the center disk  38 . To rotate the center pivot assembly  45  and the arms  21  forward to the walking position, the handle  40  is pulled toward the back of the stroller, see arrow for direction in  FIG. 18 . This movement of the handle  40  results in the arms  21  moving from the neutral jogging position of  FIG. 18  to the walking position of  FIG. 19 . Once in the walking position the arms  21  are secured to the frame with clamps  41  mounted to each side of the frame  11 . The handle  40  is then re-tightened. The final step to convert to the walking position is to loosen the fitting  26  ( FIG. 5 ), between the upper tube section  27  and the second tube section  25  and rotate the upper tube section  27  so the handgrip  22  is in a more horizontal position, see  FIG. 14 . 
     There will be occasions when the jogger needs to remove a hand from one of the arms  21  of  FIG. 5 . The stroller arm  21 , which is still grasped by the jogger&#39;s other hand remains to do all of the work to push the stroller; however, with the positional dependence of the present invention it is required that there be a force to counter the forward force exerted by the jogger&#39;s remaining arm or the arm  21  of the stroller  10  would just move without resistance until it hit the clamp  41  mounted to the frame  11 . To provide a counter force, the arms  21  are locked into their current positions by squeezing the optional brake handle  54  on the arm of the stroller. As seen in  FIG. 5  and detailed in  FIG. 20 , a disk  55  is mounted to the split clamp  28  and when the brake handle  54  is squeezed a caliper style brake  56  grips the disk  55 . The brake handle  54  has a lock button, which can be used to maintain this locked state where the arms will not rotate relative to each other. To unlock, the brake handle  54  is squeezed again and the caliper  56  unlocks from the disk  55 . The other brake handle  68  is the brake for one of the stroller wheels, in this embodiment the front wheel. 
     Due to the positional dependence between the arms there is no need for external resistance devices to assist in propelling the stroller. Consider the right stroller arm. If the jogger were to place only his right hand on the right arm and move the arm forward, the arm would move forward, but, with no resistance, the stroller does not. However, since the right and left arms are coupled together, as the right arm moves forward the left arm will move backward. Now, if the jogger were to place his left hand on the left stroller arm he would feel the force supplied to the right stroller arm transferred into the left stroller arm. To equalize the forces the jogger would, through his left arm, exert the same force as his right arm. The net result is both arms are exerting forces in the forward direction and the stroller will move forward. The stroller requires a force, F, to move forward. At any instant during the motion of the stroller arms the jogger applies ½ F to one arm and reacts with a ½ F with the other arm to balance, such that the total from the jogger&#39;s left and right arms, ½ F+½ F=F the force needed to move the stroller forward. 
     Although the above invention has been described with respect to a three-wheeled stroller, it is understood that the invention also applies to other stroller configurations, such as four or more wheeled strollers. It is also understood that the occupant or occupants of the stroller may be any size, from an infant to a full-grown adult depending upon the size and configuration of the stroller. The invention also applies to wheeled vehicles for transporting freight, animals and other non-human cargo. The invention can also be applied to sports training and rehabilitation equipment; that is, the arm positional dependence mechanism could be attached to various loads for strength training. While the foregoing invention has been described in terms of the embodiments discussed above, numerous variations are possible. Accordingly, modifications and changes such as those suggested above, but not limited thereto, are considered to be within the scope of following claims.