JPH06107267A - Bicycle with electric motor - Google Patents

Abstract

PURPOSE:To travel comfortably by bicycle all the time by controlling output rate of an electric motor to depressing force to increase/decreasse according to increase/decrease in human body index in a device driving an electric drive system according to changes in manual stepping force. CONSTITUTION:Rotation which is input by stepping a pedal is transmitted to a drive shaft 30 via a crankshaft 32 and a one-way crutch, while rotation which is input by a motor 22 is transmitted to a drive shaft 30 via a one-way clutch 48 so as to rotate a rear wheel 14 by rotating the drive shaft 30 via a one-way clutch 43. In this case, a potentiometer 72 for detecting depressing force, a speed detection means 34, and a human body index detection means 88 for seeking human body index indicating phisical strength and fatigue degree are provided so as to input respective detection signals into a controller 82. And a drive force is controlled so as to increase/decrease output rate of the motor 22 to the stepping force according to increase/decrease in man power index. Thereby constant comfortable driving by bicycle is guaranteed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention provides a driving system driven by human power and a driving system driven by an electric motor in parallel, and controls the driving force driven by the electric motor in response to changes in driving force driven by human power (hereinafter referred to as pedaling force). The present invention relates to a bicycle with an electric motor.

[0002]

2. Description of the Related Art In a bicycle equipped with an electric motor, the purpose of assisting the electric motor is mainly to reduce fatigue of the driver. In this case, it is desirable that the user can ride comfortably without feeling fatigue. However, the degree to which this fatigue is felt depends not only on the physical strength and physical condition of the driver, but also on the slope of the road, the road surface condition, and the wind direction.

A conventional proposal has been to drive and stop the motor simply by manually operating the switch, but with this, the assisting force of the motor becomes constant.
Depending on the physical strength of the driver, comfortable driving may not be possible.
The pedaling force F _L detected and the driving force F _M constant ratio of the motor relative to the pedal force F _L (hereinafter this ratio of assist ratio eta)
It is also proposed to increase / decrease by
590, JP-A-2-74491, etc.).

[0005]

[Problems of the prior art] When the assisting force F _M of the motor is increased or decreased depending on the magnitude of the pedaling force F _L , when the driver with strong physical strength rides, the motor assisting force becomes excessive and unnecessary battery consumption occurs. Will be caused or the vehicle speed will be unnecessarily increased.

Further, if the same driver is set so that an appropriate assisting force can be obtained on a flat ground, the driver feels insufficient power on the uphill. Conversely, if the assisting force suitable for the uphill is set, on the flat road. Assistance becomes excessive.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances. Even if there is a difference in the physical strength, physical condition, or fatigue level of the driver, or if the running load changes significantly on a slope,
It is an object of the present invention to provide a bicycle with an electric motor, which always obtains an appropriate assisting force of a motor to allow comfortable running.

[0008]

According to the present invention, an object of the present invention is to provide a bicycle with an electric motor in which a human power drive system and an electric drive system are provided in parallel and the output of the electric drive system is controlled in response to a change in pedaling force due to human power. A pedaling force detecting means for detecting a pedaling force, a vehicle speed detecting means for detecting a vehicle speed, a human body index detecting means for obtaining a human body index indicating the physical strength / fatigue of a driver, and a ratio of the driving force of the electric motor to the pedaling force. And a controller that controls the driving force of the electric motor so as to increase / decrease corresponding to the increase / decrease of the human body index.

Here, as the human body index, an index showing the physical strength, physical condition or fatigue of the driver such as heart rate, blood pressure, respiration rate, body temperature and the like can be used. Therefore, the human body index detecting means is formed by a sensor that detects these indexes of the driver.

[0010]

1 is a side view of an embodiment of the present invention, FIG. 2 is a power system diagram thereof, FIG. 3 is an exploded view of the power system, FIG. 4 is a side view showing a pedaling force detecting portion, and FIG. FIG. 6 is a sectional view taken along the line V-V, FIG. 6 is a characteristic diagram of the auxiliary ratio η, and FIG. 7 is a diagram showing changes in the auxiliary ratio η during traveling.

In FIG. 1, reference numeral 10 is a main frame, which extends obliquely downward and rearward from the head pipe 12 to the rear wheel 1.
4 axles. A seat tube 16 is fixed so as to be substantially orthogonal to the main frame 10, and a seat post 20 supporting a saddle 18 is fixed to an upper end of the seat tube 16.

At the lower part of the seat tube 16, a cylindrical portion 16a which opens downward is formed, and the DC electric motor 22 is accommodated therein. A power unit 24 is fixed to the lower end of the seat tube 16. The power unit 24 includes a bottom bracket case (hereinafter referred to as a BB case) 26,
The rear stay 28 extends rearward from the BB case 26, and the rear wheel 14 is fixed to the rear end of the rear stay 28. The drive shaft 30 is inserted through the right rear stay 28 (FIG. 3).

Next, the power unit 24 will be described. Figure 1,
In FIG. 3, a crank shaft 32 is inserted through the BB case 26, and cranks 34 are fixed to both ends thereof. Crank pedals 36, 36 are attached to the crank 34.

The left end of the axle 38 of the rear wheel 14 is fixed to an end plate 28a fixed to the left rear stay 28,
The right end of the axle 38 is fixed to a bevel gear case 40 fixed to the right rear stay 28. A hub 42 is rotatably held on the axle 38, and the drive shaft 3 is attached to the hub 42.
The rotation of 0 is transmitted via the bevel gear mechanism 44.

The electric motor 22 is fitted and fixed to the BB case 26 from above as shown in FIG. 3, and the motor shaft 22a thereof is positioned orthogonal to the crank shaft 32 and near the center in the vehicle width direction. The BB case 26 is the seat tube 1
The motor 22 is inserted into the tubular portion 16a of No. 6 from below and is fitted into the tubular portion 16a, and is coupled by four bolts 46 (see FIG. 3).

As shown in FIG. 3, the rotation of the motor 22 is rotatably held by the crankshaft 32 via a one-way clutch 48, a planetary gear type speed reducer 50, a small bevel gear 52, and a large bevel gear 54. Is transmitted to the cylindrical resultant force shaft 56. The rotation of the resultant shaft 56 is further transmitted to the drive shaft 30 by the bevel gear mechanism 58.

Rotation from the rear wheel 14 toward the motor 22 is interrupted by a one-way clutch 43 installed in the hub 42.
Incidentally, the planetary gear type speed reducer 50 is a known one, and transmits the revolution of the planetary gear, which is interposed between the sun gear rotated by the motor 22 and the ring gear fixed to the BB case 26, to the bevel gear 52. It is a thing.

On the other hand, the rotation input by the human power from the pedal 36 is transmitted to the large bevel gear 54 through the crankshaft 32, the one-way clutch 60, and the planetary gear type speed increaser 62. Therefore, the rotation input from the crankshaft 32 is transmitted from the large bevel gear 54 to the drive shaft 30 via the resultant shaft 56 and the bevel gear mechanism 58. The rotation of the crankshaft 32 is caused by the action of the clutch 48 while the motor 22 is stopped.
Does not reach. The rotation of the motor 22 is not transmitted to the crankshaft 32 due to the action of the clutch 60 while the crankshaft 32 is stopped or in reverse rotation. The drive shaft 30 is
It is located on the right side of the plane A in the vehicle front-rear direction including the shaft 22a (see FIG. 3).

As shown in FIGS. 3 and 5, the planetary gear type speed increaser 62 includes a ring gear 62a fixed to the large bevel gear 54,
A sun gear 62b fixed to the pedal effort detection lever 64 and a planet gear 62c interposed therebetween are provided. The crankshaft 32 revolves the planetary gear 62c via the one-way clutch 60.

The pedal effort detecting lever 64 constitutes a part of the pedal effort detecting means 65 for detecting the driving force when the pedal 36 is manually driven by the reaction force applied to the sun gear 62b. The pedal effort detection means 65 is located on the left side of the plane A.

That is, the lever 6 of the pedal effort detecting means 65
4 has two protrusions 64a and 64b as shown in FIGS.
One of the protrusions 64a comes into contact with the stopper 66 and restricts rotation in the clockwise direction in FIG. 4, in other words, rotation in the direction opposite to the direction in which the pedaling force of the pedal 36 is applied. Another second lever 68 comes into contact with the protrusion 64b, and the counterclockwise rotation of the lever 64 causes the second lever 68 to rotate clockwise.

A return spring 70 imparts a return habit to the second lever 68, whereby the lever 64 is moved to the position shown in FIG.
The habit of returning to the clockwise direction is given by. And this second
The amount of rotation of the lever 68 is transmitted to a potentiometer 72 as a pedaling force sensor. As a result, the lever 64 rotates in the clockwise direction in FIG. 4 in proportion to the pedaling force of the pedal 36, and the second lever 68 rotates in the clockwise direction, so that the pedaling force can be obtained from the rotation amount of the potentiometer 72.

In FIG. 1, 80 is a rechargeable battery such as a lead acid battery, and 82 is a controller, which are housed between the head pipe 12 and the seat tube 16 of the main frame 10. In FIG. 1, reference numeral 84 is a vehicle speed detecting means provided facing the large bevel gear.
A known structure for electromagnetically or optically detecting the rotation of the can be used.

The pedal force F _L detected by the potentiometer 72
The vehicle speed S detected by the vehicle speed detecting means 84 is
The controller 82 receives the pedal force F.
_The motor current is controlled based on _L and the vehicle speed S to generate the motor torque T _M.

In FIG. 2, reference numeral 82a denotes a memory, in which the characteristic indicating the auxiliary rate η with respect to the human body index H is recorded. This auxiliary rate η is defined by F _M / F _L as described above, and increases as the human index H increases. The human body index H used here is detected by the human body index detecting means 88.

The human body index detecting means 88 has a sensor attached to, for example, a band wrapped around the driver's hand or foot, a clip that holds the earlobe of the driver, or the like, and detects the heart rate read by these sensors. Based on this, the human body index H is obtained. The human body index H may be determined using other data such as the blood pressure, the number of breaths, and the body temperature together with the heart rate. Furthermore, the rate of increase or decrease of the heart rate or the number of breaths is used, or the heart rate or the number of breaths before running is input in advance, and the degree of load on the driver is determined using these changes during the run, and this is used as a human index. It may be used as H.

Various characteristics can be used as the characteristics to be stored in the memory 82a. It is possible to select a desired characteristic or create a desired characteristic by the switch 82c shown in FIG. 2 according to the driver's preference. You may It is also possible to input basic data such as the gender, age, and weight of the driver before traveling so that the optimum characteristics are automatically selected.

Further, the physical strength test may be automatically determined after the running for a certain period of time. For example, it may be possible to determine whether the driver's physical strength and endurance are superior or inferior to the average sex and endurance of the driver in terms of gender and age, and output the result. The human body index H may be rapidly increased or a warning may be issued when the blood pressure, body temperature, or the like reaches a certain value or more.

As shown in FIG. 7, the controller 82 reads the average human body index H within the fixed measurement period τ after the start of the vehicle from the human body index detecting means 88, and the assist rate η in the next measurement period τ. From the characteristics stored in the memory 82a.

Then, using this auxiliary ratio η, the motor driving force F _M in the measurement period τ is calculated by F _M = η · T _L. The controller 82 determines that the driving force of the motor is F
_The motor current is controlled so that it becomes _M.

In the above embodiment, the vehicle speed detecting means 84 is provided so as to face the large bevel gear 54.
It may be provided on the front wheel 86 as indicated by A. However, when it is provided between the crankshaft 32 and the one-way clutch 43 as in the embodiment, if the crankshaft 32 is stopped at the time of downhill, the speed S = 0 and the energy consumption can be further reduced. .

In the above embodiment, the rear wheel 14 is driven by the transmission system including the shaft drive mechanism using the drive shaft 30. In the present invention, however, the sprocket is fixed to the resultant shaft 56 to form the chain drive mechanism. The rear wheels 14 may be driven by a system.

[0033]

As described above, according to the present invention, the index indicating the physical strength and fatigue of the driver, that is, the human index H is obtained, and the assist ratio η (= motor driving force by the motor corresponding to the increase or decrease of the human index H is calculated. since those increasing or decreasing the F _M / pedal force F _L), even if there is a difference in physical strength and physical condition or fatigue level of the driver, also be varied greatly traveling load, etc. hill, always suitable motor assist You can drive comfortably by generating force (F _M ).

[Brief description of drawings]

FIG. 1 is a side view of an embodiment of the present invention.

[Fig. 2] Power system diagram

[Fig. 3] Development view of the power system

FIG. 4 is a side view showing a pedaling force detection unit.

FIG. 5 is a sectional view taken along line VV.

FIG. 6 is a characteristic diagram of the auxiliary rate η

FIG. 7 is a diagram showing changes in the auxiliary ratio η during traveling.

[Explanation of symbols]

 14 Rear Wheel 22 Electric Motor 72 Treading Force Detection Means 82 Controller 84 Vehicle Speed Detection Means 88 Human Body Index Detection Means

Claims (1)

[Claims] 1. A pedaling force detecting means for detecting a pedaling force in a bicycle with an electric motor, wherein a human-powered driving system and an electric driving system are provided in parallel, and the output of the electric driving system is controlled in response to a change in the pedaling force due to human power. The vehicle speed detecting means for detecting the vehicle speed, the human body index detecting means for obtaining a human body index indicating the physical strength / fatigue of the driver, and the ratio of the driving force of the electric motor to the pedal effort corresponding to the increase or decrease of the human body index. A bicycle equipped with an electric motor, comprising: a controller that controls the driving force of the electric motor so as to increase or decrease.