JPH09142369A - Manual driving gear - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify wiring, prevent poise mixing and extend a life of a device, by measuring a change of man power or a change of torque generated by the man power, wirelessly transmitting a measuring result to a control device, and controlling a drive assist means in accordance with the measuring result. SOLUTION: A detection means detects a change amount of man power applied to an input part 20 or a change amount of torque generated by the applied man power. A transmitter 44, connected to the detection means, transmits a detection result by the detection means. A transmitting device 4 constituted by the detection means and the transmitter 44 is provided in a man power drive system 2 of a man power driving gear. A receiving device receiving a signal from the transmitting device 4 is connected to a control device arranged in the man power driving gear.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention mainly relates to a bicycle,
The present invention relates to a human-powered driving device for vehicles such as a three-wheeled vehicle, a wheelchair, and a rowing boat, and more particularly to a device that includes driving assisting means such as an electric motor and drives human power as a main driving force and the driving assisting means as an auxiliary driving force.

[0002]

2. Description of the Related Art An electric motor is connected to a drive system of a bicycle,
Using human power as the main driving force source and electric motor as the auxiliary driving force source,
A so-called "bicycle with an electric motor" that is driven by the resultant force has been put into practical use. In order to maintain a good driving feeling of the bicycle, the auxiliary power from the electric motor is generally applied with a strength proportional to the torque generated by human power. As a method for detecting torque due to human power
As shown in FIG. 18, in Japanese Patent No. 4-321482, a torsion bar is used for a drive shaft (91) connected between pedals of a bicycle with an electric motor through a crank arm, and a twist gauge of a torsion bar is used to measure a twist amount of the torsion bar. 92) discloses a measuring method.

[0003]

The strain gauge (92) is attached to the rotating drive shaft (91). Therefore, it is necessary to take out the measured resistance value from the strain gauge (92) by relaying the slip ring (93) and the brush (94). The slip ring (93) and brush (94) will wear out after prolonged use,
There were cases where noise was included in the measured values and accurate measured values could not be obtained. The wear of the slip ring (93) and the brush (94) may shorten the life of the device.

According to the present invention, a change in human power or a change in torque generated by human power is measured, the measurement result is wirelessly transmitted to a control device, and the drive assisting means is controlled in accordance with the measurement result, whereby the wiring The purpose is to simplify, prevent noise from mixing, and prolong the life of the device.

[0005]

In order to solve the above-mentioned problems, in the present invention, a human-powered driving device for assisting a driving force by a driving assisting means (3) controlled by a control device (5) ( Detecting means (41) for detecting the amount of change in the human power applied to the input unit (20) or the amount of change in the torque generated by the applied human power in the human power drive system (2) of 1), and the detecting means.
A control device (5) provided in the human power drive device (1), comprising a transmitter (4) connected to (41) and comprising a transmitter (44) for transmitting the detection result of the detection means (41). ) Is connected to a receiving device (51) that receives a signal from the transmitting device (4).

Detecting means (41) provided in the human power drive system (2)
Measures the amount of change in the human power applied to the input section (20) or the amount of change in the torque generated by the applied human power, and sends the measurement result wirelessly from the transmitter (44) to the receiving device (51). However, in the control device (5) linked to the receiving device (51),
The drive assisting means (3) is controlled so as to generate the drive assisting force according to the measurement result.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION In the following, the present invention is applied to drive assisting means (3)
An example in which the bicycle (11) equipped with the electric motor (31) is used as the above will be described with reference to the flowchart in FIG. 1. still,
In the following description, “front” means the front wheel (14) side, and “left” means the left side when the bicycle (11) is viewed from the rear. As shown in FIG. 2, a bicycle (11) with an electric motor is provided with a handle (13) and a front wheel (14) at a front portion of a frame (12), so that the frame (1
A saddle (15) is provided at the upper center of 2). The endless chain (1
Sprocket (28) and (17) with 6) stretched are deployed respectively.
The human power drive system (2) includes a front sprocket (hereinafter referred to as "drive sprocket (28)") and a pedal device (21) connected to the drive sprocket (28). Pedal device (2
As shown in FIG. 3, 1) is a drive shaft (22) to which a drive sprocket (28) is attached, a crank arm (23) connected to each end of the drive shaft (22), and a crank arm.
Crank pin (26) protruding outward from the tip of (23),
And a pedal (27) pivotally supported by the crank pin (26). As shown in FIG. 2, the rear sprocket (17) is provided with a rear wheel (18) as an output means (10), and a pedal (27) which is an input section (20) for human power is driven to rotate. The chain (16) runs and the rear wheels (18) rotate.

As a drive assisting means (3) for assisting human power, a DC drive type electric motor (31) is mounted on a bicycle. The electric motor (31) has the speed reduction mechanism (3
2) and the one-way clutch. The electric motor (31) is connected to a power feeding section (7), and the power feeding section (7)
Is connected to a control device (5) described later. Control device
(5), power feeding unit (7), electric motor (31) and reduction mechanism (32)
Are deployed on the frame (12) in the center of the bicycle (11).

Left and right crank arms (2) of the pedal system (21)
Transmitters (4) are respectively provided in 3). Transmitter (4)
Is a piezoelectric element (42) as a detection means (41) and the piezoelectric element
A self-excited oscillator (44) electrically connected to (42) and an oscillator (4
4) A transmitting antenna (46) attached to the self-excited transmitter (44).

The left crank arm (23) will be described below, but the right crank arm (23) has the same structure. As shown in FIGS. 3 and 4, the crank arm (23) is composed of a first arm (24) on the drive shaft (22) side and a second arm (25) on the pedal side. The first arm (24) is
The base end is connected to the drive shaft (22) at a right angle, and a tube portion (24b) having a rectangular cross section is formed from the center to the tip end side, and is open at the tip end. The second arm (25) is fitted into the tubular portion (24b) of the first arm (24) such that the base end thereof has a little margin, and the tubular portion (24b) is
Is pivotally supported by a pin (24a) parallel to the drive shaft (22) at the end of the. Align the crankpin (2
6) are connected. Therefore, when you depress the pedal (27),
The second arm 25 swings around the pin 24a as shown by an arrow A in FIG. 4, and the base end is pressed against the inner surface of the upper portion of the tubular portion 24b. At this time, the contact portion of the inner surface of the tubular portion (24b) with the base end of the second arm (25) will be referred to as a "stopper (29)".
Call.

The transmitter (4) is provided on the crank arm (23). The transmitter (4) is a piezoelectric element as shown in FIG.
(42) and self-excited oscillator (44). Transmitter (4)
As an example of the above circuit, there is an LCR circuit as shown in FIG. The inside of the dotted line frame in the figure is the equivalent circuit of the piezoelectric element (42). The piezoelectric element (42) is arranged at the base end of the second arm (25) so that it can contact the stopper (29). The self-excited oscillator (44) is arranged in a space on the base end side inside the tubular portion (24b).

When the rider depresses the pedal (27) (step 1), the base end of the second arm (25) swings so as to come into contact with the stopper (29). At this time, the piezoelectric element (42) is sandwiched between the stopper (29) and the base end of the second arm (25) by the pressing force correlated with the rotation angle of the crank arm (23) and the pedaling force of the pedal (27). , Voltage is generated (step 2). As shown in Fig. 4, the rotation angle of the crank arm (23) from the vertical position is θ.
Then, if the pedaling force of the pedal (27) is as shown in Fig. 7,
The voltage generated by the piezoelectric element (42) can be shown as in FIG. In addition, "left" in the figure is the left pedal (27), "right"
Means the right pedal. The self-excited oscillator (44) operates by using the voltage generated in the piezoelectric element (42) as a power source, and the LCR circuit self-excitedly vibrates at a frequency peculiar to the circuit and transmits (step 3). The amplitude due to self-excited vibration is proportional to the magnitude of the voltage. That is, the amplitude is proportional to the amount of change in the pressing force applied to the piezoelectric element (42). When the piezoelectric element (42) generates the voltage shown in FIG. 8, the amplitude due to self-excited vibration is, for example, as shown in FIG.
It is as shown in. The voltage generated by the piezoelectric element (42) and the amplitude due to self-excited vibration will be described in detail in Examples.

As shown in FIG. 6, the control device (5) comprises a receiving device (51) and a control section (6) linked to the receiving device (51). The control unit (6) is connected to a power feeding unit (7) described later. The receiving device (51) is composed of a bandpass filter (53) to which a receiving antenna (52) is attached, and an amplitude demodulation circuit (54) connected to the bandpass filter (53). Signal transmitted from the transmitting antenna (46) (Fig. 9)
Is received by the receiving antenna (52) (step 4) and detected by the bandpass filter (53), and the amplitude demodulation circuit (5
It is demodulated in step 4) (step 5, FIG. 10).

The control unit (6) is mainly composed of a CPU (61). The CPU (61) is connected to the amplitude demodulation circuit (54) via an amplification circuit (62), an amplitude measurement circuit (63), a memory (64), a comparison circuit (65) and a drive control circuit (66). ) Is connected. The amplitude measuring circuit (63) measures the amplitude of the signal (FIG. 10) sent from the amplitude demodulating circuit (54) through the amplifying circuit (62) and transmits it to the CPU (61). The drive control circuit (66) is connected to the power feeding unit (7) and controls the current supplied to the electric motor (31) of the power feeding unit (7) according to a command from the CPU (61). The memory (64) stores in advance the amount of current supplied to the electric motor (31) corresponding to the amplitude of the signal as an address. The comparison circuit (65) compares the amplitude of the signal sent to the CPU (61) with the supply current corresponding to the amplitude stored in the memory (64), and supplies the electric current value to the electric motor (31) (Fig. 11) is determined (step 6), and a command is transmitted to the power supply unit (7) via the drive control circuit (66) so as to supply the current value to the electric motor (31). The electric motor (31) is driven by the current value supplied from the power supply section (7) (step 7).

By driving the electric motor (31) based on the torque generated by the pedaling force as described above, the driving of the bicycle (11) can be assisted by the electric motor (31). When the pedal (27) on the opposite side is depressed, the same control as described above is performed and the auxiliary drive force is applied from the electric motor (31).

For example, it is possible to provide a speed detector (not shown) on the rear wheel (18) so as to limit the driving force assist by the electric motor (31) when the speed of the bicycle (11) exceeds a certain speed. .

In the above example, both crank arms (23) (2
Although the piezoelectric element (42) is provided in 3), the piezoelectric element (42) is provided only in one of the crank arms (23), the current value to be supplied is stored, and when the pedaling force is applied to the other, It is also possible to adopt a configuration in which the current is supplied at the stored current value. The attachment position of the piezoelectric element (42) is not limited to the above example, and may be attached to the stopper (29) or may be provided inside the circular frame P of FIG. Further, as shown in FIG. 12, a cylindrical portion (25a) is formed on the second arm (25), and a circular frame Q
The piezoelectric element (42) may be arranged in either one of them.

As a different method for measuring the torque generated by the pedaling force, as shown in FIG. 13, a pedal 27 is a casing type pedal support having an open top and one side pivotally supported by a crank pin 26. (27a) and a pedal plate (27b) slidably arranged on the pedal support (27a), and the downward movement of the pedal plate (27b) inside the pedal support (27a). The stopper (29) that prevents
A piezoelectric element (42) may be provided between the (29) and the pedal plate (27b). The self-excited transmitter (44) is the pedal support (27a).
It can be placed inside. In this case, the force of a person stepping on the pedal (27) is directly applied to the piezoelectric element (42), and the signal transmitted from the self-excited oscillator (44) becomes a signal proportional to the pedaling force. In order to measure the torque, an angle sensor for measuring the rotation angle of the crank arm (23) is provided on the frame (12) and connected to the control device (5), and the amplitude of the input signal and the angle sensor.
The torque may be obtained from the measurement angle (not shown), and the current supplied to the electric motor may be determined in the same manner as above.

When a strain gauge is used as the detection means (41), the strain gauge and the oscillator (44) are electrically connected, and a power supply unit (not shown) such as a battery or a battery is connected. Good.

[0020]

EXAMPLES The voltage generated when a pressing force is applied to the piezoelectric element (42) will be described in detail below with reference to examples of the present invention. As the transmitter (4), the LCR circuit shown in FIG. 5 is used, and the piezoelectric element (42) has a piezoelectric ceramic (zirconate titanate Pb (Zr.
Ti) O ₃ ) was used. Table 1 shows the elements used.
Shows the value.

[0021]

[Table 1]

When the force applied to the piezoelectric element (42) of the circuit having the above construction is F, the generated voltage V is V = F · d ₃₃ / Cd
(However, d ₃₃ : equivalent piezoelectric coefficient 300 × 10 ⁻¹² C / N). Therefore, when a force of F = 980N is applied to the piezoelectric element (42), both generated voltages are considered to be 470V. The voltage and current vibrating in the self-excited oscillator (44) at this time are as shown in FIGS. 14 and 15 for the first embodiment and as shown in FIGS. 16 and 17 for the second embodiment. Since the amplitude of vibration is a value proportional to the amount of change in the applied force, the self-excited oscillator (44)
A change in the force applied to the piezoelectric element (42) can be measured by detecting the amplitude of the signal transmitted from the device and measuring the amplitude.

[0023]

According to the present invention, since the change in torque due to the human power applied to the human power drive unit (1) is measured and wirelessly transmitted to the control unit (5), the slip in the transmission of the change in human power is detected. No ring, brush, etc. are required, and no wiring is required. Therefore, it is possible to prevent the occurrence of wear, the occurrence of noise, and the like, and it is possible to extend the life of the device. or,
When the piezoelectric element (42) is used as the power source of the transmitting device (4), a power source such as a battery and a battery for operating the transmitting device (4) is unnecessary, and the device can be downsized.

The description of the above embodiments is for the purpose of illustrating the present invention and should not be construed as limiting the invention described in the appended claims or reducing the scope thereof. Further, the configuration of each part of the present invention is not limited to the above-described embodiment, and it is needless to say that various modifications can be made within the technical scope described in the claims.

[Brief description of the drawings]

FIG. 1 is a flowchart showing a flow of operations of the present invention.

FIG. 2 is an overall view of a bicycle with an electric motor.

FIG. 3 is a plan view of a human power drive system.

FIG. 4 is an enlarged sectional view of a crank arm.

FIG. 5 is a circuit diagram of a transmission device.

FIG. 6 is a block diagram of a transmission device and a control device.

FIG. 7 is a graph showing a relationship between a rotation angle of a crank arm and a pedaling force of a pedal.

FIG. 8 is a graph showing the relationship between the rotation angle of the crank arm and the voltage generated by the piezoelectric element.

FIG. 9 is a graph showing a relationship between a rotation angle of a crank arm and a transmission signal of a self-excited oscillator.

FIG. 10 is a graph showing a relationship between a rotation angle of a crank arm and a demodulated received signal.

FIG. 11 is a graph showing the relationship between the rotation angle of the crank arm and the current supplied to the electric motor.

FIG. 12 is a diagram showing another embodiment of the present invention.

FIG. 13 is a diagram showing another embodiment of the present invention in which a transmission device is provided on a pedal.

FIG. 14 is a graph showing a generated voltage in the self-excited oscillator according to the first embodiment.

FIG. 15 is a graph showing a generated current in the self-excited oscillator according to the first embodiment.

FIG. 16 is a graph showing the voltage generated in the self-excited oscillator according to the second embodiment.

FIG. 17 is a graph showing a generated current in the self-excited oscillator according to the second embodiment.

FIG. 18 is an enlarged view of a drive shaft showing a conventional torque detection method.

[Explanation of symbols]

 (11) Bicycle with electric motor (2) Manual drive system (23) Crank arm (24) First arm (25) Second arm (4) Transmitter (42) Piezoelectric element (44) Self-excited oscillator (5) Control device

Claims (3)

[Claims] 1. A human power drive system (2) having an input section (20) to which human power is applied, and a drive assist means (3) for assisting the drive of the human power drive system (2) are connected to an output means (10). Drive assist means
(3) is a human-powered drive that is controlled by a control device (5) and transmits a desired driving force to an output means (10). In the human-powered drive system (2), an input section (20) is added. Detecting means (41) for detecting the amount of change in human power or torque generated by applied human power, and a transmitter (44) connected to the detecting means (41) and transmitting the detection result by the detecting means (41). The control device (5) is connected to a receiving device (51) that receives a signal from the transmitting device (4), and the receiving device (51) receives the signal. A human power drive device characterized in that the drive assisting means (3) is controlled according to the received signal. 2. The detecting means (41) comprises an input section (20) and an output means.
A piezoelectric element (42) provided between the piezoelectric element (42) and the piezoelectric element (42), which is connected to the self-excited oscillator (44) and measures the input human power or changes in torque due to human power. Generates a voltage in response to a change in human power, and the self-excited oscillator (44) operates by using the voltage generated by the piezoelectric element (42) as a power source and transmits a signal having an amplitude proportional to the voltage. The human-powered drive device according to claim 1, wherein: 3. A human power drive system (2) having an input section (20) to which a pedaling force is applied by a pedal device (21), and a drive assisting means (3) for assisting the drive of the human power drive system (2). In the bicycle (11) provided with, the pedal device (21) projects outward from the crank arms (23) linked to both ends of the drive shaft (22) and the tips of the respective crank arms (23). The crank pin (26) is provided, and the pedal (2
7), and at least one crank arm (23) is attached to the drive shaft (2
2) side arm (24) and pedal side arm (25) .One arm is pivotally supported on the other arm so as to be swingable within the rotation plane. Of (25), one arm is equipped with a stopper (29) that regulates the swing range of the other arm in the turning direction, and the contact portion between the stopper (29) and the mating arm has The pedal device (21) is equipped with a piezoelectric element (42) linked to a self-excited oscillator (44), and the bicycle (11) receives a signal from the self-excited oscillator (44). The control device (5) is connected to the device (51) and controls the drive assisting means (3) according to the received signal, and when human power is applied to the pedal (27), the crank arm (23)
The torque generated in the is applied to the piezoelectric element (42) as a pressing force,
The piezoelectric element (42) generates a voltage proportional to the change in pressing force,
Using the voltage generated by the piezoelectric element (42) as a power source, the self-excited oscillator (44) transmits a signal having an amplitude corresponding to the voltage and controls the drive assisting means (3) according to the transmitted signal. Characteristic bicycle.