JP2003026070A - Pedaling mechanism of bicycle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve motional performance of a bicycle only by the replacement of a pedal arm unit and installation of auxiliary part to a conventional general bicycle by enhancing an average value of torque generated in a driving shaft 23 by pedaling operation while accompanying a trigonometric functional change. SOLUTION: The pedal arm unit for internally installing one-way feed mechanism, an installing member, a pedal arm return means, and a rocking angle regulating means in a pedal arm is installed on the driving shaft. Left and right pedal arm units are made to perform pedaling operation in a driving angle range for always obtaining high torque.

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pedaling mechanism for a bicycle that rotates a rear wheel by alternately depressing a pair of left and right pedals. 2. Description of the Related Art In a conventional bicycle, a pedal arm whose phase is shifted by 180 degrees is fixed to a main shaft penetrating and fixed to a driving sprocket for applying a rotating torque to a rear wheel. The foot is alternately stepped down by 180 degrees with the foot to rotate the drive sprocket, which is transmitted to the rear wheel to advance the bicycle. [0003] When the pedal is depressed and turned 180 degrees by a human foot, the kicking force from the top to the bottom is large near the horizontal position of the pedal. However, when the pedal position is at the upper limit side, it is a force to push forward from behind. In addition, on the lower limit side, the force is a force of scratching from the front to the back, which is a movement that humans are not good at. [0004] To solve the problem of the above-mentioned conventional bicycle, Japanese Patent Laid-Open No.
In 1-70889, the left and right pedal arms are alternately oscillated in the right and left directions in an efficient angle range based on the horizontal position, and torque is applied to the drive sprocket via the one-way feed mechanism. In order to continue the cycle in which the pedal is depressed alternately left and right, the depressed pedal arm must return to the original position while depressing the other pedal arm. To solve this problem, Japanese Patent Application Laid-Open No. 11-7088
In No. 9, a reverse rotation mechanism is provided around the drive main shaft, and the left and right pedal arms are forcibly operated in reverse. FIG. 11 shows a conventional bicycle in which the torque obtained when the pedal arm is in the horizontal position is 100.
FIG. 7 is a torque curve diagram showing a torque ratio depending on a position angle of a pedal arm, and an average torque ratio at this time is about 64%. FIG. 12 is a torque curve diagram obtained by Japanese Patent Application Laid-Open No. 11-70889 and the embodiment of the present invention. The average torque ratio is about 90%. This makes it possible to greatly improve the running performance of the bicycle. However, in order to realize the function disclosed in Japanese Patent Application Laid-Open No. H11-70889, capital investment in a production process is required due to a structural change around a drive spindle, and the number of parts is increased. Costs also increase. Also, no modification is possible for consumers who have purchased conventional bicycles. [0008] In order to solve the above problems, the present invention employs a one-way feed mechanism in a pedal arm and a swing angle for setting an effective range when the pedal arm is depressed. Regulatory measures;
The pedal arm unit has a built-in resetting means for returning the depressed pedal arm and replaces it with the pedal arm of a conventional bicycle.A stopper that sets the reference position of the pedal arm with respect to the main body is attached to the bicycle body. It is configured to be attached. In the present invention, return means is used without using a forced reversing mechanism for alternately pressing the left and right pedal arms. The reason is, for example, that when a human walks, when the right foot touches the ground, the left foot is not forcibly raised.After depressing the pedal, the action of raising the foot should be followed by the pedal. It is. According to this structure, the conventional bicycle is
This is achieved by attaching the pedal arm unit to the drive spindle and attaching a stopper as an accessory to the bicycle body. Further, since the forced reversing mechanism is not required, there is no need to change the mechanism around the drive spindle, so that a large capital investment is not required in the production process. In addition, an increase in the number of parts is suppressed, which is advantageous in cost. In the present invention, the left and right pedal arms are completely independent, and the position of the pedal before riding is located on both the left and right sides by the return means, but the driver alternately pedals as if walking normally. You just need to step on it. In addition, since traveling is possible only by operating the pedal on one side, it is theoretically possible to travel even to a person who has difficulty with one leg or a person who has hurt one leg. An embodiment of the present invention will be described with reference to FIGS. As shown in FIG. 2, when the force for depressing the pedal 12 is F and the length of the pedal arm is L1, the torque T applied to the drive spindle is T = F × COS θ,
The torque curve according to the position of the pedal arm is a curve of the trigonometric function itself. FIG. 11 is a torque curve of a conventional bicycle in which the pedal is rotated 360 °, and the average torque is about 64% of the peak torque. The movable range of the swing angle θ of the pedal arm of the present invention was set to ± 45 ° based on the horizontal position. The torque curve at this time is as shown in FIG. 12, and the average torque is about 90% of the peak torque, and the transmission efficiency is greatly improved. On the other hand, the vertical stroke L2 due to the pedaling operation is equal to the pedal arm length L1 of the conventional bicycle.
In contrast, in the embodiment of the present invention, the swing angle is ± 45
°, L2 = L1 × SIN45 ° = 1.4L1
, Which is about 70% of the conventional stroke. As shown in FIG. 3, the pedal arm unit is dedicated to the right side 10 and the left side 20, and the left and right shapes are approximately symmetrical. Pedal arms 11, 2
A pedal 12 for stepping on the pedal with a foot is rotatably fixed to the tip of the pedal arm 1, and an outer ring of a one-way feed mechanism 13 (hereinafter referred to as a one-way clutch) is provided at the fulcrum in the pedal arm. It is stuck. The outer peripheral portion of the mounting member 14 is fitted inside the one-way clutch 13 so as to prevent the one-way clutch 13 from coming off in the thrust direction with a retaining ring or the like. As shown in FIGS. 4 and 5, the distal end of the drive spindle 23 of the conventional bicycle is provided with a screw hole at the center for attaching a pedal arm and a serration process of an uneven shape for preventing the outer periphery from rotating. Have been. The inside of the mounting member 14 is machined so as to fit into the serration shape of the driving main shaft 23, and the pedal arm units 10 and 21 can be fixed to the driving main shaft 23 by the mounting screws 16. After the pedal 12 is depressed, the pedal must return to its original position in order to continue the cycle. In this embodiment, the return means is provided on the opposite side of the fulcrum of the pedal arm from the pedal side. Weight is fixed in the pedal arm. The weights are balanced so that the pedal side is always above the fulcrum. A spring or the like may be used as the returning means for returning the pedal to its original position. However, in the embodiment, a weight is used to simplify the mechanism. In addition, because the return means is configured with the balance ratio between the pedal side and the weight side, if the pedal side is not lightened, the pedal arm unit will be heavy, the shape will be large, and the appearance will be deteriorated. And the weight was iron. As shown in FIG. 8, inside the weight,
A groove a for setting the swing angle of the pedal arm unit is dug over 90 °, and position setting means (stoppers) 92 and 96 fixed to the bicycle main body side engage with these grooves, and Swing angle is ± 45
° is set as appropriate. In addition, the right pedal arm has a slightly different shape from that on the left due to the engagement with the chain cover, and the weight is changed so that the moment in the return direction of the pedal arm is the same on the left and right sides. . In the embodiment, the one-way feed mechanism 13 is shown in FIG.
As shown in Fig. 5, a commercially available cam-type one-way clutch was used. The outer race 25 of the one-way clutch and the pedal arms 11 and 21 are fixed by press-fitting and detent keys. As shown in FIG. 7, when the pedal arm is depressed, the outer race 25 of the one-way clutch rotates clockwise. Then, since the cam 19 inscribed between the mounting member 14 and the outer ring 25 rotates in the C1 direction, the AB length becomes a flat rod and meshes with the inner and outer rings. The outer race 25, the cam 19, and the mounting member 14 corresponding to the inner race are integrally transmitted to transmit the torque on the pedal arm side to the drive main shaft 23. When the foot separates from the pedal 12, the pedal arm unit is actuated in the opposite direction by the weight, and when the outer ring 25 is turned counterclockwise, the cam 19 rotates in the C2 direction, and the pin (AB)
Is released, the inner and outer wheels idle, and the pedal 12
Can return to its original position. As a result, when the right pedal arm unit is depressed, the one-way clutch 13 is locked, torque is transmitted to the drive main shaft 23, and the drive sprocket is rotated. If the left foot is lifted naturally when stepping on the right foot in the same manner as when a person steps on the foot, the left pedal arm unit 10 acts on the left foot by the reverse torque due to the weight, and the one-way clutch 13 rises on the left foot by idling, and the right foot is lifted. At the end of the step, continue with your left foot,
The driving can be started in the same manner, and the pedaling operation can be continued. Although the one-way feed mechanism is an example, the one-way feed mechanism may be a ratchet mechanism used inside the driven sprocket of the rear wheel of the bicycle, which can perform the same operation. In such a pedaling operation of the bicycle, the driver can take various driving modes within the movable range of the pedal arm unit. That is, in a situation where a child who cannot take a large pedal stroke or the driver is tired, a small stroke may be used, and a person who has trouble with one foot or a person who has hurt one foot can drive even with a petaling operation with one foot. . As described above, the pedaling mechanism according to the present invention eliminates the upper and lower limit pedal operation ranges of poor transmission efficiency compared to the conventional pedal operation of rotating the pedal by 360 °. Because the reciprocating pedal operation range is limited only to the area based on the horizontal position with good transmission efficiency, as described above, the riding performance of the bicycle, such as climbing performance, acceleration performance, and maximum speed, is greatly improved. The variety of driving modes of the driver has been expanded. Further, in realizing the bicycle of the present invention, capital investment is suppressed by not requiring a significant change in the conventional production process, and the bicycle is provided as a kit including a pedal arm unit and accessories. Also, the effect that the performance of the conventional bicycle can be improved can be expected for the purchased user.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an overall external view of an embodiment. FIG. 2 is an explanatory diagram of a pedal arm portion of the embodiment. FIG. 3 is a sectional view of a driving unit according to the embodiment. FIG. 4 is an assembly explanatory view of the pedal arm unit. FIG. 5 is an explanatory view of a mounting member 14; FIG. 6 is an external view of a one-way clutch. FIG. 7 is an explanatory diagram of a one-way clutch. FIG. 8 is an explanatory diagram of a return means (weight). FIG. 9 is an explanatory view showing an embodiment for limiting a swing angle. FIG. 11 is a torque curve diagram of a conventional pedaling mechanism. FIG. 12 is a torque curve diagram of the pedaling mechanism of the embodiment and JP-A-11-70889. [Description of Signs] 10 Right pedal arm unit 11 Right pedal arm 12 Pedal 13 One-way feed means (one-way clutch) 14 Mounting member 15 Cap 16 Mounting bolts 17, 22 Return means (weight) 20 Left pedal arm unit 21 Left pedal arm 23 Drive main shaft 30 Drive wheel 40 Torque transmitting means (chain) 50 Follower wheels 92, 96 Position setting means (stopper) a Swing angle regulating means

Claims (1)

Claims: 1. A torque generated by alternately depressing a pedal arm of a bicycle, through a torque transmitting means,
In a bicycle pedaling mechanism for transmitting to a rear wheel, a one-way feed mechanism is provided in left and right pedal arms, a return means for returning a stepped down pedal arm to an original position, and a swing angle for restricting a movable range of the pedal arm. A pedaling mechanism having a regulating means, a mounting member for transmitting torque from a one-way feed mechanism and fixing a pedal arm to a driving main shaft of a bicycle, and a position setting means for setting a movable position of the pedal arm.