Patent ID: 9114848
Filing Date: 2015-08-25
Classification: B62K,B62M

Abstract:
1. A pedal drive system for propelling a multi-wheeled cycle comprising: a cycle frame having a steerable front wheel and at least one driven wheel; first and second pedal arms, each having a support member for supporting a respective foot of the user, and wherein each said support member is hingably supported by said cycle frame at a proximal end of said pedal arm; a drive spindle, supported by said cycle frame between said first and second pedal arms, having a toothed member for transmitting a driving force to said at least one driven wheel, using a flexible transmission element and a rear wheel toothed member; said pedal drive system further comprising first and second two-bar linkages connecting respective said pedal arms to the said drive spindle, wherein said two-bar linkages each further comprise an inner bar fixed to said drive spindle, and an outer bar connected to said inner bar, and wherein said inner bars have one connector crank pin each connected to the outer bar and the outer bar has one pedal crank pin, respectively, located between the distal and proximal ends of the said pedal arms connected to said pedal arm, the distance between the pedal crank pin and the proximal ends of the pedal arms being either longer by a radius distance line L-L or shorter by radius distance line M-M relative to a radial line distance N-N between the sprocket axis and the proximal ends, but not the same as N-N to avoid lock-down at end of stroke positions; and wherein said each connector crank pin remains 180 degrees apart around the said drive spindle and are substantially offset either in front of or behind, but not over or aligned with top dead center and the drive spindle axis at end of stroke positions and wherein both said outer bar linkages have differing angular relationships with respect to the said respective inner bar linkages at said first and second pedals' end of stroke positions; and wherein one or the other said first and second pedal arms can always apply rotating force to the said inner bars' connector crank pins without the necessity of rotational force being returned back to the said inner bars' connector crank pins by means of the rotation of the said driven wheel and said pedal arms and the first and second said two bar linkages are configured so as to rotate said drive spindle about its rotational axis per each pedal downward stroke, when one pedal arm is all the way down or at the bottom of its respective stroke, the opposite pedals' said pedal crank pin is already positioned beyond a top dead center of the drive spindle thus insuring continuous rotation of the drive system is sustained independently of the back drive wheel rotational momentum, and wherein such connector crank pin is not directly above or below, but substantially offset either in front of or behind, but not aligned above or below with the top dead center and the drive spindle at each stroke of the pedal at end of stroke positions and wherein both said outer bar linkages have differing angular relationships with respect to the said respective inner bar linkages at said first and second pedals' end of stroke positions to prevent pedal reversal or lockup; and wherein the said drive system further includes a one-way clutching, freewheel mechanism.