JP3015707U - Bicycle drive - Google Patents

Abstract

(57) [Abstract] [Purpose] An object of the present invention is to provide an inexpensive bicycle drive device that can be easily attached to an existing bicycle, has a simple structure, is hard to break down, and is inexpensive. [Structure] A rotating part by a helical gear is provided inside a crank gear, and a drive main body equipped with an electric motor is provided behind a drive part provided with a bevel gear meshing with the helical gear so as to be operable between a crankshaft and a saddle frame. It is a composition.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a bicycle drive device that assists human pedal force when a foot is strained, such as on a slope or when there is a lot of luggage.

[0002]

[Prior art]

 In conventional bicycle drive devices, when a person steps on a pedal, a motor exerts its power to assist in reducing the pedaling force by about half.When a person steps on the pedal, the sensor detects the pedaling force and pedal rotation instantaneously. However, based on these two pieces of information, the control unit controls the force of the motor against the pedal effort in less than 1: 1 in real time.

[0003]

[Problems to be solved by the device]

 In the above-mentioned form, an electric control device such as a crank rotation sensor / pedal force sensor and a control unit is required, and the structure is complicated, so that a failure easily occurs, and the selling price is expensive from 130,000 to 140,000 yen. It is difficult to spread. The present invention is intended to solve the above drawbacks, and an object thereof is to provide an inexpensive bicycle drive device that is easily attached to an existing bicycle, has a simple structure, and is not easily broken.

[0004]

[Means for Solving the Problems]

 As a means to solve it, a rotating part using a helical gear is provided inside the crank gear, and a drive main body equipped with an electric motor is operated between the crankshaft and saddle frame at the rear part of the drive part with a bevel gear that meshes with the helical gear. It is a form that is provided as much as possible.

[0005]

【Example】

 Next, an embodiment of the present invention will be described with reference to the drawings. Reference numeral 1 is a bicycle drive device. Numeral 2 is a rotary portion formed by a helical gear which is provided inside the crank gear A of the bicycle so that its center is coaxial with the crank shaft B, and is integrally formed. Reference numeral 3 denotes a drive body, and a bevel gear 3a3 that meshes with the rotating portion 2 by the helical gear is provided in a trapezoidal frame body 3a2 having a U-shaped support piece 3a1 that is clamped on the crankshaft B at the tip thereof. A rechargeable electric motor 3b for rotating the bevel gear 3a3 (which uses an electric drill or an electric screwdriver, for example, a torque of 30 kg / cm or more is used) is integrally connected to the rear portion of the drive unit 3a. The electric motor 3b is fixed to the saddle frame C of the bicycle with a band 3b1, a compression spring 3b3 is provided at the tip of the sleeve 3b2, and a rod-shaped operating pin 3b4 having an L-shaped rear end is formed. Is mounted, and the electric motor 3b is connected by a fixing piece 3b5 so as to be operable up and down. The saddle frame C is provided with a locking pin 3b6 for pulling up and locking the operating pin 3b4.

According to the bicycle drive device 1 of the present invention, the bevel gear 3a3 is preliminarily pulled up and locked to the locking pin 3b6 by pulling up the operating pin 3b4 when the pedaling force is not required when traveling on level ground. By separating the rotating part 2 by the helical gear, the pedal D can be stepped on as usual for traveling. In addition, when the load is exerted on the foot such as a slope, by removing the operation pin 3b4 from the locking pin 3b6, the drive body 3 is pushed downward by the force of the compression spring 3b3, and the rotating portion 2 by the bevel gear 3a3 and the helical gear is pushed. Engage. Next, by operating the electric motor 3b, the bevel gear 3a3 is rotated, the rotating portion 2 by the helical gear is interlocked, the crank gear A can be rotated, and a slope or the like can be climbed. At this time, the pedal D can also rotate at the same time, and it suffices to put the foot on the pedal D and synchronize with the rotation speed of the crank gear A. Also, when the charge amount decreases and the rotation speed of the electric motor 3b decreases, It is also possible to assist the electric motor 3b by lightly stepping on the pedal D with the foot.

It should be noted that the electric motor 3b is not limited to a rechargeable type, but may be a battery type or the like, and may be arbitrarily determined as needed. Further, a switch for operating the electric motor 3b is provided on the handle. Furthermore, the method of moving the drive body up and down is not limited to the operation pin, and other methods may be used.

[0008]

[Effect of device]

 According to the drive device for a bicycle of the present invention, the bicycle can be easily attached with a slight modification of the existing bicycle, and since the structure is simple, it is hard to break down and can be provided at a low cost.

[Brief description of drawings]

FIG. 1 is a front view of a main part showing an embodiment of the present invention.

FIG. 2 is a right side view showing an embodiment of the present invention.

[Explanation of symbols]

 1 --- Bicycle drive device 2 --- Rotating part 3 --- Drive body A --- Crank gear B --- Crank shaft C --- Saddle frame D --- Pedal

Claims (1)

[Scope of utility model registration request] 1. A drive main body having an electric motor mounted at the rear of a drive part provided with a rotating part formed by a helical gear inside a crank gear and a bevel gear meshing with the helical gear, is operable between a crankshaft and a saddle frame. A bicycle drive device characterized by being provided.