JPH11152072A - Eccentric crank device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an eccentric crank device that reduces the momentum of freed by automatically increasing the length from its crankshaft to pedal shafts at the tip of the crank when a pedal pressure is applied so that the burden on feed is lightened and automatically decreasing that length when fed are raised. SOLUTION: The eccentric crank device comprises cranks and eccentric wheel storage cases 2 placed at the tip of the cranks. The cranks are exclusively for a right foot and a left foot. The eccentric wheel storage cases 2 each internally hold a front-side eccentric wheel or disk and a rear-side eccentric wheel or disk together with a bearing so that a pedal 13 and the eccentric wheel 3 thus obtained are rotatably coupled on both the ends of a hexagon rod pedal shaft. By this structure, while the cranks are having periodic motion, the driven eccentric wheel 3 and the pedal shaft automatically changed the length from a crankshaft to the pedal shaft advantageously be double the maximum eccentricity in dependence on their positions.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a crank device for a bicycle crank or an engine for converting a linear motion into a rotary motion.

[0002]

2. Description of the Related Art Conventionally, a crank device of this type rotates at a fixed distance between a fulcrum portion for applying pressure to the tip of a crank 1 and a crank shaft, as in a conventional crank track shown in FIG. It has a structure to do. And this rotation orbit draws a perfect circular orbit.

[0003] Others include engines,
Most crank devices in the field of converting linear motion into rotary motion, such as machine tools, rotate at a constant interval between the crankshaft 14 and a portion to which power is applied. Is to be drawn.

[0004]

However, the former has a structure in which the length of the crankshaft 14 and the length of the pedal shaft 10 rotate at a constant interval, both in the rotating portion to which power is applied and in the rotating portion not requiring power. And there is a problem that it is not possible to avoid useless momentum.

[0005] In the case of the latter engine,
When the piston applies pressure to the tip of the crank and when the crank applies pressure to the piston, the length between the two shafts is the same, resulting in a reduction in motive power.

The present invention has been proposed in view of the above, and it is an object of the present invention to automatically extend the length between the crankshaft and the pedal shaft when applying a linear motion to the crank. A strong force can be applied to the crankshaft, and when rotating from the bottom dead center 19 to the top dead center 18, the length between the crankshaft and the pedal shaft can be automatically changed to reduce the momentum. It is an object of the present invention to provide an eccentric crank device capable of saving energy.

[0007]

According to the present invention, a crank 1 is provided.
And an eccentric wheel storage case 2 provided at the tip of the crank 1. Inside the eccentric wheel storage case 2, a front side cartridge bearing receiving portion 8a and a rear side
The bearing receiving portion 8b protrudes at the central portion, and the bearings on both sides are received at the central portion, thereby achieving the above object. Also, the eccentric wheel storage case 2 has a front eccentric wheel 3a and a rear eccentric wheel 3b mounted on both sides together with a cartridge bearing from both sides, and the eccentric wheel fixing screw 9a can be mounted via the eccentric ring fixing screw hole 9b, thereby achieving the above object. doing. Further, a hexagonal pedal shaft hole 10b is provided in the central portion of the pedal 13, a hexagonal rod-type pedal shaft 10a is inserted, and the pedal shaft caulking pins 12a penetrate through the pedal shaft caulking pin holes 12b and 12c to be fixed. Achieves the above objectives. Further, the hexagonal rod type pedal shaft 10a integrated with the pedal 13 is inserted into the front pedal shaft hole 4a and the rear pedal shaft hole 4b of the eccentric wheel 3 and can be attached with the pedal shaft fixing screw 11a, thereby achieving the above object. ing. Although the disassembled parts shown in FIG. 4 can be mounted by the above procedure, only the right crank is shown here because the bicycle is symmetrical.

[0008]

FIG. 1 is a side view of an embodiment of the present invention, and FIG. 4 is an exploded perspective view. In the figure, reference numeral 1 denotes a hexagonal rod type pedal shaft 10 in which the left and right foot parts mounted on the bicycle are matched with the eccentric type crank device, and are displaced and fixed inside the eccentric ring storage case 2 at the tip end of the crank.
a is a structure in which the interval between the crankshaft 14 and the pedal shaft 10a always changes advantageously during the periodic rotational movement of the crank 1. As will be described in detail later, the power of the foot can be efficiently increased during running, and This is to reduce the amount of exercise.

Until the pedal 13 and the crank 1 rotate 90 degrees forward from the position of the top dead center 18, the hexagonal pedal shaft 10
a and the length of the crankshaft 14 gradually increase to the maximum length. These operations result in that the pedal shaft 10a at the displacement point of the eccentric wheel 3 is driven in the opposite direction during the periodic movement of the crank 1, so that the pedal shaft moves outward inside the eccentric wheel storage case 2 and consequently. It is designed to be far from the crankshaft 14. Since the lever principle is a product of the lengths, the longer the length of the crankshaft 14 and the length of the pedal shaft 10a, the more advantageous.

On the other hand, the crank 1 and the pedal 13 are
The length of the crankshaft 14 and the hexagonal bar-shaped pedal shaft 10a gradually decreases until the shaft rotates from the fulcrum toward the bottom dead center. I'm going back. In these operations, the pedal shaft at the displacement point of the eccentric wheel 3 is driven in the opposite direction during the periodic rotation of the crank 1, so that the outermost pedal shaft inside the eccentric wheel storage case 2 moves inward. By doing so, it comes to approach the crankshaft 14 as a result. As described above, the crank 1 and the pedal 13 are formed by automatically extending the length of the crankshaft 14 and the pedal shaft during the section using the driving force of the foot from the top dead center 18 to the bottom dead center 19. One step to return to is completed.

Further, the structure in which the distance between the crankshaft 14 and the pedal shaft is changed to be long in the rotating portion where the pedaling force is required is to reduce the burden on the foot.

As shown in FIG. 5, the slanted portions of the ball pushing one 7 and the ball receiving one 8 in the eccentric ring storage case 2 are provided with a front side cartridge bearing 5 and a rear side cartridge bearing 6, and the eccentric ring 3 has both sides. The eccentric wheel 3 and the pedal shaft 10a are smoothed when the eccentric wheel 3 and the pedal shaft 10a are driven inside the eccentric wheel storage case 2 by applying pressure from the front and fixing them with screws. Further, since the inner central portion of the eccentric wheel storage case 2 has a projection shape, the eccentric wheel 3 is prevented from falling out during rotation.

A hexagonal rod-shaped pedal shaft 10 is also provided.
The shape of a is to be integrated with the eccentric ring 3, and this shape may be a square rod shape. However, there is a necessary condition that the pedal 13, the shaft and the eccentric ring must be absolutely three-piece integrated. This is because the frictional portion when the crank 1 is driven in conjunction with the periodic movement must be other than the cartridge bearings on both sides.

The interval between the crankshaft 14 and the pedal shaft 10a gradually decreases from the bottom dead center 19 to the fulcrum rotated 90 degrees from the bottom dead center 19 to the top dead center 18, but this fulcrum is rotated during one rotation. It is the shortest part. These changes are due to the phenomenon that the pedal shaft 10a moves inward by the amount of eccentricity according to the periodic movement of the crank 1. In addition, until reaching the position of the top dead center 18 from this fulcrum,
The rotation is performed while the interval between the two shafts is gradually changed to a long time, and the rotation is returned to the original start point, and the two strokes are completed. When the right and left strokes are repeated for one and two strokes, the left and right two strokes are activated, so that the length between the crankshaft 14 and the pedal axle becomes mutually advantageous during both strokes. A great change is possible.

In the crank device of the eccentric mechanism described above, as shown in the displacement diagram of the pedal shaft shown in FIG. 7, each position of the hexagonal bar-shaped pedal shaft 10a is represented by a graph when the crank 1 makes one rotation. . A in this graph represents the crankshaft 14 when the foot is depressed between the upper fulcrum and the bottom dead center.
And the change with respect to the length between the pedal shaft. As described above, although the length between the two axes is one stroke that increases when the pedaling force is applied, the relationship between the position of the follower of the pedal axis and the two axes is shown. These eccentric amounts move by twice the eccentric amount.

The line C shown in FIG. 7 is based on the conventional unchanged orbit.

The portion B shown in FIG. 7 is the opposite of the case A, but one rotation when the hexagonal pedal shaft 10a reaches the fulcrum 9 'from the position 6' (bottom dead center). The position between both axes is the shortest. When the pedal shaft 10a rotates from the position 9 'to the fulcrum 12', when the length between the two shafts increases for the first time and reaches the position 12 ', the length returns to the starting point.

As shown in FIG. 6, a hexagonal pedal shaft 1
It can easily be seen that 0a is always maintained at the same position.
To make this possible, top dead center 18 to bottom dead center 1
Between 9, the interval between the crankshaft 14 and the hexagonal rod-type pedal shaft 10 a is long. These operations always operate automatically, and the eccentric wheel 3 as a follower is used.
It is possible to obtain a larger amount of eccentricity by enlarging the contour of.

Further, comparing the dotted trajectory shown in FIG. 6 with the solid circular trajectory, the front is longer than before and the burden on the foot can be reduced. On the rear side, the crank device of the present invention is shorter than in the conventional art, enabling the foot momentum to be significantly reduced.

According to the first aspect of the present invention, the driving force of the rotating city is generated by the force of the human foot pedaling the crank, and when the foot depresses the crank, the force between the crankshaft and the pedal shaft is generated. Achieved by using a modification of the eccentric mechanism that allows the length of the pedal to be extended, the same length produces the advantageous effect of automatically and accurately changing operation when and when pedaling force is not required. That is, the foot depresses the pedal during the period between the top dead center and the bottom dead center of the crank and the pedal. If this operation is defined as the first stroke, the crankshaft and the pedal are rotated when the first stroke is rotated. The distance between the shafts is extended by twice the amount of eccentricity by the eccentric wheel driven by the eccentric wheel, thereby reducing the burden on the foot and providing an innovative effect of applying a strong force to the rear wheel of the bicycle. In addition, the crank and the pedal perform an operation of lifting the foot and the pedal between the bottom dead center and the top dead center. If this operation is defined as a second stroke, the crankshaft and the pedal are rotated when the second stroke is performed. It is possible to reduce the length between the shafts by the function of the eccentric ring, thereby reducing the foot momentum.
The structure of these eccentric mechanisms is a mechanical type with a high degree of perfection in which no structural trouble occurs, and thus has an effect suitable for long-time use.

[Brief description of the drawings]

FIG. 1 is a side view of the present invention in use at the time of boarding.

FIG. 2 is a perspective view and a plan view of the overall shape of the present invention.

FIG. 3 is a plan view and a cross-sectional view of the same crank part.

FIG. 4 is a plan view and a cross-sectional view of the eccentric ring portion of the above.

FIG. 5 is an exploded perspective view of an important part of the device of the present invention.

FIG. 6 is a cross-sectional view of the configuration when the device of the present invention is mounted.

FIG. 7 is an explanatory diagram comparing a conventional trajectory with a trajectory of the apparatus of the present invention.

FIG. 8 is an explanatory diagram showing a change in length and force at each position of a dashed axis by dividing a rotational trajectory of the device of the present invention into 12 equal parts.

FIG. 9 is a side view of a conventional crank.

[Description of Signs] 1 Crank 1a Right Crank 1b Left Crank 2 Eccentric Wheel Storage Case 3 Eccentric Wheel 3a Front Eccentric Wheel 3b Back Eccentric Wheel 4a Front Pedal Shaft Hole 4b Back Pedal Shaft Hole 5 Front Cadridge Bearing 5a Front Bearing 6 Back Cadridge・ Bearing 6a Backside bearing 7 Ball push one 8 Ball receiver one 8a Front side ball receiver one 8b Back side ball receiver one 9a Eccentric ring fixing screw 9b Eccentric ring fixing screw hole 9c Back side eccentric ring fixing screw hole 10 Conventional crankshaft 10a Hexagonal rod type Pedal shaft 10c Pedal shaft hole 11a Pedal shaft fixing screw 11b Pedal shaft fixing screw hole 12a Pedal shaft caulking pin 12b Pedal shaft caulking pin hole 12c Pedal caulking pin hole 13 Pedal 14 Crank shaft 14a Crank shaft hole 14b Crank shaft stopper claw 15 Large gear 16 Choi 17 Frame 18 Top dead center 19 Bottom dead center 20a Trajectory when applying the pedaling force of the device of the present invention 20b Trajectory when raising the leg of the device of the present invention 21a Trajectory when applying the pressing force of the conventional crank 21b Leg of the conventional crank Orbit when lifting

Claims (1)

[Claims] A crank (1) and the crank (1)
And an eccentric storage case (2) provided at the tip of
These cranks (1) are provided on the left and right, respectively, and an eccentric mechanism is mounted inside the eccentric wheel storage case (2), and is rotatable via a front-side cartridge bearing (5) and a rear-side cartridge bearing mechanism. The hexagonal rod-type pedal shaft (10a) is displaced into the front eccentric wheel (3a) and the rear eccentric wheel (3b) and is inserted and fixed.
An eccentric crank device characterized in that when the crank (1) is rotated in conjunction with the pedal (13), a difference of twice the amount of eccentricity occurs.