JPH11321765A - Offset crank device continuously using body weight effectively for maintaining stable acceleration force in pedaling drive of bicycle and the like - Google Patents

Abstract

PROBLEM TO BE SOLVED: To always link body weight to rotational force effectively so as to maintain stable acceleration force in pedaling in a bicycle and the like. SOLUTION: Left and right cranks 3 are separated from a bearing for a chain ring 6. The chain ring 6 and a slide gear 7 are fixed so as to be turned by means of a hook 5 integrated with the crank 3. The axes of rotation of the left and right hooks 5 are positioned on the same line and set parallelly to the axis of rotation of the chain ring 6. The hooks 5 turn the chain ring 6 while sliding along two slits putting the center of the slide gear 7 between them.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an offset crank device that keeps making effective use of weight in transmitting power from right and left cranks to a chain ring of a rotary pedaling drive portion of a bicycle or the like.

[0002]

2. Description of the Related Art Left and right cranks and a chain ring of a rotary pedal drive portion of a conventional bicycle or the like which is rowed by human power are integrated.

[0003]

In a conventional bicycle, a rickshaw or a rickshaw to which the pedal is applied, when pedaling, the position of the pedal reaches the highest point, immediately before, immediately after, and reaches the lowest point. At the moment, immediately before and immediately after, the direction of gravity is close to or perpendicular to the direction of rotation, so applying weight alone does not produce a strong rotational force; it moves forward near the highest point and backwards near the lowest point. We need to work toward. And, when one of the left and right pedals is in this range, the other pedal is always in this range. Therefore, there is a problem that when the pedal is in this range, the rotational force decreases and the acceleration force decreases.

[0004] It is an object of the present invention to be able to maintain a stable acceleration force by constantly connecting the weight efficiently to the rotational force when pedaling in a bicycle or the like.

[Means for Solving the Problems]

In order to achieve the above object, the left and right cranks (3) and the chain ring (6) are separated in the rotary pedal drive part of the present invention. The rotation axes (1) of the left and right cranks are on the same straight line, while the rotation axes (2) of the chain ring and the slide gear are parallel but different from each other.

[0006] The left and right cranks have a small crank (4) and a hook (5) in a structure as if the crank and pedal were made smaller. The hook is a chain ring (6)
Into the slit (8) which is opened from near the center of the slide gear (7) fixed to the outside. The rotation axis (2) of the slide gear fixed to the chain ring is positioned inside the rotation path of the hook, so that the rotation path of the hook is inside the rotation path of the outer edge of the slit of the slide gear. When the crank rotates, the hook rotates the chain ring (6) and the slide gear (7) while sliding in the slit.

The slide gear is supported so that the left and right cranks (3) and the slide gear (7) can rotate freely, respectively, by removing the center part and wrapping the slide gear from the outside. Penetrate.

In the above structure, the pedal (9)
And rotate the crank (3), as shown in Fig. 4, the left and right hooks (5) draw a circular orbit around the crank axis (1), and the left and right hooks are always connected to the chain ring. It is located symmetrically about the rotation axis (2) of the fixed slide gear. When the chain ring (6) rotates at a constant speed, the pedal periodically changes its rotation speed during one revolution. As a result, one of the left and right pedals always moves within a certain angle D of 180 degrees or less about the rotation axis.

By adjusting the distance between the rotation axis (1) of the crank and the rotation axis (2) of the slide gear and the radius of rotation of the hook (5), the magnitude of the fixed angle D can be adjusted.

By adjusting the angle in the rotation direction of the crank (3) and the hook (5) or the direction in which the rotation axis (1) of the crank and the rotation axis (2) of the slide gear are shifted, a constant angle D is obtained. Since the direction in which the pedal is positioned from the center of rotation can be adjusted, the center of the constant angle D is set to a position where the weight is most utilized by the rotational force.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described based on embodiments with reference to the drawings. In FIG. 1, the main parts are a crank (3) integrated with a small crank (4) and a hook (5), a chain ring (6), a slide gear (7), a pedal (9), a frame (10), Rotating bearing (11) for slide gear, right bracket (12), left bracket (13), slide gear position adjusting screw (1)
4) The rail (16).

The frame (10) has a pipe-like portion having a diameter corresponding to that of a conventional bicycle bearing, and has a slide gear bearing (11) therein. The pipe-shaped part has a chain slit (17) as a path for the chain.

The chain ring (6) and the slide gear (7) are fixed with screws. The center part of the slide gear is cut out round, and the center of the slide gear is
Slit (8) with width just enough for book and hook
Is open.

The left and right brackets (12, 13) have a structure like a female type and a male type in order to freely and independently rotate around a common rotation axis while maintaining strength. And set the crank bearing (1
Receive in 5).

The left and right hooks (5) are slide gears (7).
Into the slit (8) so as to be sandwiched from the left and right. It is preferable that the hook rotates freely.

In order to be able to adjust the magnitude of the effect of this device, a rail (16) is attached to the slide gear bearing so that the slide gear itself can slide, and the slide gear is adjusted with a slide gear position adjusting screw (13). .

In the embodiment shown in FIG. 2, the left and right brackets (18, 19) of the female type and the male type are incorporated in the bearing portion of the frame of the conventional bicycle, and like the hour hand and the hour hand of the timepiece. Attach each small crank (20) to the right side of the left and right brackets. The slide gear bearing (22) is fixed to the frame (23) so that the slide gear (21) is set between the left and right small cranks.

In the embodiment shown in FIG. 3, the bracket (24) is not separated left and right, and the left small crank (26) and the left hook (27) are attached to the right-hand part of the frame (25). Right hook (27) on right crank (28)
Attach, the right crank is not fixed with the bracket,
Rotate freely. The slide gear bearing (3) is set so that the slide gear (29) is set between the left and right small cranks.
0) is fixed to the frame.

Since the present invention is configured as described above, it has the following effects.

When this device is mounted on a bicycle or the like,
There is no moment when one pedal is at the highest point and the other pedal is at the lowest point. When one pedal is depressed to the lowest point, the other pedal has already passed the highest point, and it has come to a point where it is easy to make use of weight when depressing, so it can be efficiently converted to rotational force by shifting weight and stable Can maintain the accelerated force.

[Brief description of the drawings]

FIG. 1 is a sectional view A (a) and a sectional view B showing the structure of an offset crank device attached to a pedal drive portion.
(B).

FIG. 2 is a side view and a sectional view showing an embodiment of the offset crank device.

FIG. 3 is a side view and a sectional view showing an embodiment of the offset crank device.

FIG. 4 is a diagram showing how the pedal moves when the slide gear rotates by 45 degrees and makes one rotation.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Rotation axis of crank 2 Rotation axis of slide gear 3, 28 crank 4, 20, 26 Small crank 5, 27 Hook 6 Chain ring 7, 21, 29 Slide gear 8 Slit 9 Pedal 10, 23, 25 Frame 11, 22, Reference Signs List 30 slide gear bearing 12, 18 right bracket 13, 19 left bracket 14 slide gear position adjusting screw 15 crank bearing 16 rail 17 chain slit 24 left and right integrated bracket

Claims (1)

[Claims] 1. A disk-shaped slide gear (7) having two slits (8) opened in a straight line with a center interposed therebetween, the left and right cranks each rotating independently while sharing a rotation axis. An offset crank device in which hooks (6) rotate around an axis slightly deviated from the center of a crank axis while moving in corresponding slits.