JP3230760B2 - Bicycle with electric motor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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

[0002]

2. Description of the Related Art It is known to detect a treading force and to control a driving force by an electric motor in accordance with the magnitude of the treading force (Japanese Utility Model Application Laid-Open No. 56-75990, Japanese Unexamined Patent Publication No. 2-7449).
That is, when the load of human power is large, the driving force by the motor is increased to reduce the load of human power. Here, a one-way clutch is interposed in the drive system of the motor, and when the motor is not energized or when the vehicle speed is higher than the rotational speed of the motor, the motor is driven.
To prevent them from being turned around.

[0003]

2. Description of the Prior Art In this conventional apparatus, since the motor is constantly driven, there is a problem that the energy consumption of the battery increases and the traveling distance becomes short. Therefore, it is conceivable to increase the battery capacity, but there is a problem that the vehicle weight increases.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has an electric motor capable of greatly increasing the traveling distance when motor driving is used together without increasing the battery capacity. The purpose is to provide bicycles.

[0005]

According to the present invention, it is an object of the present invention to provide a bicycle with an electric motor which has a human-powered driving system and an electric driving system arranged in parallel and controls the output of the electric driving system in response to a change in the pedaling force. A pedaling force detecting unit that detects a vehicle speed, a vehicle speed detecting unit that detects a vehicle speed, a pedaling force reference value determining unit that determines a reference value based on the vehicle speed, a comparing unit that compares the pedaling force with the reference value, A motor driving force calculating means for setting the driving force to be output by the electric driving system to 0 when the value is smaller than a reference value.

That is, the driving of the motor is limited to the minimum necessary case, and the driving force by the motor is reduced to 0 when running with a small pedaling force. Here, the motor drive is used in combination with the flat road running resistance _RD when the vehicle runs at a constant speed on a flat road.
Actual pedal force F _L than pedal force reference value F ₀ calculated based on the
Is desirably set to be large. For example, when the time and starting acceleration of the time and head wind uphill mode - but a combination of motor drive, the pedal force reference value F ₀ time less than that calculated based on the pedal effort F _L is the running resistance R _D mode - Stop the combination of data It is designed to make the most of a bicycle-like driving feeling.

[0007]

FIG. 1 is a side view of an embodiment of the present invention, FIG. 2 is a power system diagram thereof, FIG. 3 is a development view of the power system, FIG. 4 is a side view showing a treading force detecting section, and FIG. FIG. 6 is a block diagram showing the configuration of the controller, and FIG. 7 is a conceptual explanatory diagram of the control.

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

At the lower part of the seat tube 16, there is formed a cylindrical portion 16a which is opened downward, and a DC electric motor 22 is accommodated therein. A power unit 24 is fixed to a lower end of the seat tube 16. The power unit 24 includes a bottom bracket case (hereinafter referred to as a BB case) 26,
A 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,
3, a crankshaft 32 is inserted into the BB case 26, and a crank 34 is fixed to both ends of the crankshaft 32. The crank 34 has crank pedals 36 attached thereto.

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
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 its motor shaft 22a is orthogonal to the crankshaft 32 and located near the center in the vehicle width direction. The BB case 26 is a seat tube 1
The motor 22 is fitted into the cylindrical portion 16a so as to be inserted from below into the cylindrical portion 16a, and is connected by four bolts 46 (see FIG. 3).

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

As a result, the rotation of the motor 22 is transmitted to the rear wheel 14. The rotation from the rear wheel 14 to the motor 22 is interrupted by a one-way clutch 43 built in the hub 42. Note that the planetary gear type speed reducer 50 is a well-known type, and is provided between a sun gear rotated by the motor 22 and a ring gear fixed to the BB case 26 to transmit the revolution of the planetary gear meshing with them to the small bevel gear 52. Things.

On the other hand, the rotation input manually from the pedal 36 is transmitted to the large bevel gear 54 via the crankshaft 32, the one-way clutch 60, and the planetary gear type gearbox 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 not transmitted to the motor 28 by the action of the clutch 48 while the motor 28 is stopped. When the crankshaft 32 is stopped or in reverse rotation, the rotation of the motor 28 is not transmitted to the crankshaft 32 by the action of the clutch 60. Here, the drive shaft 30 is the motor shaft 2
It is located on the right side of plane A in the vehicle longitudinal direction including 2a (see FIG. 3).

As shown in FIGS. 3 and 5, the planetary gear type gearbox 62 includes a ring gear 62a fixed to the large bevel gear 54,
A sun gear 62b fixed to the pedaling force 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 pedaling force detecting lever 64 constitutes a part of the pedaling force detecting means 65 for detecting the driving force at the time of manual driving by the pedal 36 by the reaction force applied to the sun gear 62b. The treading force detecting means 65 is located on the left side of the plane A.

The lever 64 of the pedaling force detecting means 65 has two projections 64a and 64b as shown in FIGS.
The one protrusion 64a abuts against the stopper 66 to restrict the clockwise rotation in FIG. 4, in other words, the rotation in the direction opposite to the direction in which the pedaling force of the pedal 36 is applied. The projection 64b has another second
And the second lever 68 rotates clockwise by the counterclockwise rotation of the lever 64.

The second lever 68 is provided with a return behavior by a return spring 70, whereby the lever 64 is moved to the position shown in FIG.
With this, return behavior in the clockwise direction is given. And this second
Of the lever 68 is transmitted to a potentiometer 72 as a pedaling force sensor. As a result, the lever 64 pivots clockwise in FIG. 4 in proportion to the pedaling force of the pedal 36, and the second lever 68 pivots clockwise in FIG. 4, so that this pedaling force is obtained from the rotation amount of the potentiometer 72.

In FIG. 1, reference numeral 80 denotes a rechargeable battery such as a lead-acid battery, and reference numeral 82 denotes a controller, which is accommodated between the head pipe 12 and the seat tube 16 of the main frame 10. In FIG. 1, 84 is a large bevel gear 5
The vehicle speed detecting means is provided opposite to the motor 6 and has a known structure for detecting the rotation of the large bevel gear 56 electromagnetically or optically.

[0022] The pedal force F _L detected by the potentiometer 72
And the vehicle speed S detected by the vehicle speed detecting means 84 is controlled by a controller.
The controller 82 receives the pedaling force F.
_The motor current is controlled based on _L and the vehicle speed S to generate a motor torque T _M.

Next, the configuration of the controller 82 will be described with reference to FIG. The controller 82 includes a microcomputer (CPU) 88, a memory 90 for storing its operation program, a motor output control circuit 92, and an appropriate input / output interface (not shown). Prepare. The operation of the CPU 88 is shown in FIG. 6 as a functional block.

The control - the output signal of the pedal force detection means 72 is inputted to the La 82, CPU 88 is obtained by calculation in pedal force calculating means 94 the pedal force F _L on the basis of this signal. Also based on the output signal of the vehicle speed detecting means 84 obtains the map or calculating the flat running resistance R _D with respect to the vehicle speed S at this time the CPU 88, obtains the pedal force reference value F ₀ corresponding thereto map or calculation. Of course a direct map or calculation from the vehicle speed may be calculated pedaling force reference value F _0. This operation is performed by the pedaling force reference value determining means 96.

[0025] from these pedal force F _L and the depression force reference value F ₀ is compared in the comparison unit 98, a difference D = F _L -F ₀ therebetween are determined. The motor driving force calculating means 100 calculates the difference D
Driving force of motor 22 F _M - mode based on the difference D when but positive
Ask for. This calculation is performed using an equation or a map stored in advance. For example, if a is a constant, F _M
= AD. When the difference D is negative, the driving force F
_{It is} assumed that _M = 0.

[0026] Motozukimo the driving force F _M obtained in this way -
Capacitor Voltage calculation means 102 mode - obtaining the motor drive voltage V _M.
This calculation is performed, for example, as follows.

In a DC motor, the following equation is established among the applied voltage (V _M ), motor current (I), and rotation speed (N) of the motor. V _M = I · R + k · N where R is an amateur equivalent resistance, k is a proportionality constant,
k · N indicates the armature back electromotive voltage.

The motor torque (T _M ) depends on the type of series winding, partial winding, multiple winding, etc., but generally the motor current (I)
It is almost proportional to Therefore, the following equation is obtained using C as a constant. T _M = C · I Therefore, assuming that (R / C) = j, the following equation is obtained. V _M = j · T _M + k · N (1) In the equation (1), the first term (j · T _M ) on the right side is a term relating to torque, and the second term (k · N) is a rotation speed. It is a section about.

The motor - Tatoruku and mode - the relationship between the driving force F _M by data, uniquely determined if such reduction ratio and wheel radius are determined, for example, expressed by the following equation. _{F M = h · T M (} h is a constant) therefore and the (1) driving force in the expression F _M, Mo was determined from the vehicle speed S at this time - mode by entering the motor rotational speed N -
It can be obtained motor drive voltage V _M.

[0030] The thus obtained mode - Capacitor Voltage V _M is Mo - is input to the data output control circuit 92, in the circuit 92 for example motor - pulse width thyristor 104 interposed between the motor 22 and the battery 80 Voltage control is performed by a control (PWM) method.

[0031] The motor - said motor voltage V _M (1) to the voltage V _M which is determined by the formula. As shown by hatching in the Results Figure 7, mode - only example _{F M = a (F L -F} 0) between the driving force F _M by motor F _L> F _0, and the is this pedaling force F _L Will be added. That total driving force of the bicycle is in this period (F _L + F _M) becomes, F _M = 0 in the other periods
Running by only depressing force F _L is made from a.

In the above embodiment, the vehicle speed detecting means 84 is provided so as to face the large bevel gear 54.
A may be provided on the front wheel 86 as shown by A. The present invention is F _L used in the _{calculation, F M, V M, T} , N, F 0 Yade - data, etc. may be varied or increased or decreased within a range in which an effect is obtained of the present invention, the present invention is This case is included. For example,
The motor voltage V _M (1) may be slightly increased or decreased from the value determined by the equation.

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

[0034]

As described above, according to the present invention, the traveling speed (S)
And the actual pedaling force (F ₀ ) is determined.
_L ) generates a motor driving force (F _M ) only when the driving force is larger than this value. Therefore, the vehicle runs while adding a driving force by the motor only when a large driving force is required while utilizing the driving feeling of a bicycle. Will do.

Therefore, the driving time of the motor is shortened, and the traveling distance can be greatly increased without increasing the size of the battery by reducing the energy consumption of the battery. In particular, since the current flows intermittently from the battery, in the case of a lead-acid battery, the battery performance can be restored while the current is reduced, and the battery performance can be maximized and the life can be extended.

[Brief description of the drawings]

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

Fig. 2 Power system diagram

FIG. 3 is a development view of the power system.

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

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

FIG. 6 is a functional block diagram of a controller.

FIG. 7 is a conceptual explanatory view of the present invention.

[Explanation of symbols]

22 electric motor 32 crankshaft 65 the torque detection means 72 a torque detecting means 82 Controller - La 84 vehicle speed detecting means 96 reference value determining means 98 comparison means 102 motor - motor driving force computing unit S ₂ motor - data output control

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-2-74491 (JP, A) JP-A-3-153486 (JP, A) JP-A-1-314685 (JP, A) JP-A-60-1985 252087 (JP, A) JP-A-58-89483 (JP, A) JP-A-56-149277 (JP, A) JP-A-56-17775 (JP, A) JP-A-5-50977 (JP, A) JP-A-5-24575 (JP, A) JP-A 56-76590 (JP, U) JP-A 3-49195 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) B62M 23/02

Claims (1)

(57) [Claims] 1. A bicycle with an electric motor, wherein a human-powered drive system and an electric drive system are provided in parallel, and an output of the electric drive system is controlled in response to a change in a drive force (hereinafter referred to as a "pedal force") due to human power. Treading force detecting means for detecting, vehicle speed detecting means for detecting vehicle speed, treading force reference value determining means for determining a reference value that increases or decreases in response to the increase or decrease in the vehicle speed, and comparing means for comparing the treading force with the reference value, A motor driving force calculating means for setting a driving force to be output by the electric driving system to 0 when the pedaling force is smaller than the reference value.