JP3052399U - Oval chain bicycle - Google Patents

Abstract

(57) [Summary] [Purpose] When riding a bicycle, the horizontal position where it is easy to obtain the driving force by shortening the time near the top and bottom dead center of the pedal where it is difficult to obtain the driving force within a certain period of one rotation of the pedal depression A structure that can take a long time in the vicinity can facilitate acceleration. [Constitution] When the left and right pedals (2) are in the horizontal position, the ellipse chain wheel 1 mounted on the crankshaft is in phase with the line connecting the two focal points (P1) and (P2) of the ellipse being vertical. The rear wheel chain wheel 6 is connected to the rear wheel chain 6 via a tensioner 7.

Description

[Detailed description of the invention]

[0001]

[Technical field to which the invention belongs]

 The present invention relates to a method for driving a bicycle.

[0002]

[Prior art]

 The chain of the rear wheel and the perfect circular chain mounted on the crankshaft are connected by a chain, and a constant load is always applied to the pedal during acceleration regardless of its rotational position.

For this reason, in the conventional bicycle, the torque required for acceleration is not generated near the top and bottom dead center of the pedal where the depressing force is hardly changed to the turning force, and the bicycle generally stalls.

[0004]

[Problems to be solved by the invention]

 An object of the present invention is to provide a bicycle that reduces stalls caused by the above-described reasons and efficiently guides a stepping force to acceleration.

[0005]

[Means for Solving the Problems]

 According to the present invention, the above problem is solved as follows. At the position where the left and right cranks are horizontal, the line connecting the two focal points of the ellipse is vertical, and the elliptical chain wheel attached to the Kunk shaft is connected to the rear wheel chain wheel via a tensioner with a chain. I do.

[0006]

[Embodiment]

 FIG. 1 shows an embodiment of the present invention. When the left and right pedals (2) are in a horizontal position, the line connecting the two focal points (P1) and (P2) of the ellipse is in a vertical phase. An elliptical chain wheel (1) mounted on the crankshaft and a rear wheel chain wheel (6) are connected by a chain (5) via a tensioner (7).

FIGS. 2 and 3 show a conventional case in which a case in which a perfect circular chain is mounted on a crankshaft (4) and a case in which an elliptical chain are mounted in the same manner are superimposed in the same drawing. FIG. 3 clearly shows the differences between the present invention and the present invention.

In the present invention, as shown in FIG. 2, at the upper and lower dead points of the left and right pedals (2), the pedal depression force is least likely to be the rotation force of the crankshaft (4). The point (P3) on the pitch line where the pulling force is applied is located at a position having a shorter turning radius than the same point (P5) of the perfect circular chain wheel. In this case, you can move around this position faster and bigger.

Further, as shown in FIG. 3, at the horizontal position of the left and right pedals where the pedal depression force most efficiently turns the crankshaft (4), the same point (P4) of the elliptical chain is Since the turning radius is longer than the same point (P5) of the perfect circular chain, the rear wheel (8) rotates more at the same pedal rotation angle, and the rotational load of the rear wheel is constant. Takes longer.

As described above, the present invention takes a long time at a position where the driving force can be advantageously extracted during one rotation of the pedal, and shortens a stepping time at a position where the driving force is difficult to be extracted. .

[0011]

[Effect of the invention]

 For the above reasons, the present invention has the following effects. (A) The acceleration time is increased and the stall time is shortened, so that acceleration is easier than the conventional one.

(B) Since the stepping force becomes more efficient as a propulsion force, when accelerating, less fatigue is caused than in the conventional one.

[Brief description of the drawings]

FIG. 1 is a front view of a part of a bicycle showing one embodiment of the present invention.

FIG. 2 is a schematic front view showing the conventional driving mode and the embodiment of the present invention in the same drawing, when the crank is vertical.

FIG. 3 is the same schematic diagram as FIG. 2, but with the crank horizontal.

[Explanation of symbols]

 (1) Oval chain wheel (2) Pedal (3) Crank (4) Crankshaft (5) Chain (6) Rear wheel chain wheel (7) Tensioner (8) Rear wheel (A) Pitch circle of perfect circular chain (B) Pitch curve of elliptical chain wheel (C) Pitch circle of rear wheel chain wheel (D) Pitch circle of tensioner (E) Pitch line of chain 1 (F) Pitch line of chain 2 (P1) (1) Elliptical focal point (P2) Elliptical focal point of (1) (P3) Point of action 1 of force driving chain (P4) Point of action 2 (P5) Point of action 3

Claims (2)

[Utility model registration claims] 1. A bicycle in which an elliptical chain is mounted on a crankshaft. 2. A bicycle having an elliptical chain attached to a crankshaft at a position where left and right cranks are horizontal and a line connecting two focal points of an ellipse is vertical.