JPH0966882A - Power assisted vehicle - Google Patents

Abstract

(57) [Summary] (Correction) [PROBLEMS] To provide a power-assisted vehicle in which the structure of a pedal effort detection portion can be simplified, the cost can be reduced, and the installation space can be reduced. A human power drive system 9a, an electric power drive system 9b,
In the power assisted bicycle including the pedal effort detection device and the controller 11 that controls the output of the electric power drive system 9b, the planetary gear train 41 includes the sun gear 42 and the arm 4.
5 and a planetary gear 44, and the pedal depression force detection device functions as an arm urging means for urging the arm 45 in a direction to prevent the arm 45 from rotating, and a spring of the arm 45. A potentiometer 47 that functions as a rotation amount detecting means, and a controller 11 that functions as a pedal effort calculating means that calculates the pedal effort based on the detected value are provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power-assisted vehicle which is driven by supplying an auxiliary driving force corresponding to a pedaling force of an occupant.

[0002]

2. Description of the Related Art Conventionally, as a power assisted vehicle, for example, a human power drive system for traveling by human power and an electric power drive system using a motor as a power source are provided, and the human power, that is, the pedal effort of an occupant is detected and the detected value is detected. There is a power-assisted bicycle configured to control the motor according to the above to assist the occupant's pedaling force.

In the conventional power assisted bicycle described above, as a torque detecting means for detecting the pedaling force of the occupant, for example, an arm portion is integrally formed with a sun gear rotatably supported by a crankshaft, A structure in which a lever that abuts on the arm portion is rotatably supported, a potentiometer is fixed to the rotation shaft, and the lever is biased in a counter-rotation direction by a spring is adopted.

[0004]

However, the torque detecting means of the conventional power assisted bicycle described above has a problem in that the number of parts is large, the cost is high, and the required installation space is large.

The present invention has been made in view of the above conventional problems, and particularly provides a power assist vehicle in which the structure of the pedal effort detecting means can be simplified, the cost can be reduced, and the installation space can be reduced. Is intended.

[0006]

According to a first aspect of the present invention, there is provided a human power drive system for outputting a pedaling force via a planetary gear train, an electric power drive system provided in parallel with the human power drive system, and the human power drive. In a power assisted vehicle comprising a pedal effort detection means for detecting the pedal effort of the system, and an assist force control means for controlling the output of the electric power drive system according to the detected pedal effort, in the planetary gear train, A sun gear provided on a rotating shaft, an arm rotatably supported on the rotating shaft, and a planetary gear rotatably supported on the arm, wherein the pedal depression force detecting means is the arm. An arm urging means for urging the arm in a direction to prevent rotation of the arm, a rotation amount detecting means for detecting a rotation amount of the arm, and a pedal depression force calculating means for calculating the pedal depression force based on the detected value. prepare for It is characterized in Rukoto.

According to a second aspect of the present invention, in the electric power drive system according to the first aspect, the motor and the reduction shaft are arranged in parallel with the rotation shaft, and the primary small gear of the motor output shaft is a primary large gear at one end of the reduction shaft. It is characterized in that the secondary small gear at the other end of the reduction shaft is meshed with the secondary large gear having the rotation shaft as the center of rotation.

According to a third aspect of the present invention, in the second aspect, the arm urging means and the rotation amount detecting means are arranged between the primary and secondary large gears of the electric power drive system. .

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. 1 to 5 are views for explaining the power-assisted bicycle according to the first embodiment of the present invention. FIG. 1 is a schematic side view, FIG. 2 is a cross-sectional plan view of essential parts, and FIG.
3 is a cross-sectional view taken along the line III-III in FIG. 2, and FIGS. 4 and 5 are a schematic side view and a schematic plan view for explaining the gear ratio.

In the figure, 1 is a power assisted bicycle,
Reference numeral 2 is a frame of the bicycle 1. This frame 2
A head pipe 2a that steerably supports a front fork 4 having front wheels 3 rotatably supported, a down tube 2b extending rearward and downward from the head pipe 2a, and a seat tube erected at a rear portion of the down tube 2b. 2c, a pair of left and right chain stays 2d connected to the rear end of the down tube 2b, and a pair of left and right seat stays connecting the upper part of the seat tube 2c and the rear end of the chain stay 2d. 2e and.

A steering handle 7a is mounted on the upper end of the front fork 4, and a saddle 7b is mounted on the upper end of the seat tube 2c. Further, the rear wheel 8 is rotatably supported at the connecting portion between the chain stay 2d and the seat stay 2e.

Reference numeral 9 is a drive device for the power-assisted bicycle 1. The drive device 9 includes a human power drive system 9a for driving the rear wheels 8 by an occupant's pedal force, an electric power drive system 9b for outputting an auxiliary drive force by electric power, a pedal force detection device 40 for detecting the pedal force, and A controller (assist force control means) 11 that controls the output of the electric power drive system 9b according to the detection value of the detection device 40 is provided.

The human power drive system 9a includes a pedal 17 and a crank 16 to which the occupant's pedal force is applied, and the crank 1
6 is a crankshaft (rotating shaft) 1 attached to both ends thereof
3 and a pedaling force transmission device 41 that accelerates the rotation of the crankshaft 13 and transmits it to the rear wheel 8. The crankshaft 13 is rotatably supported by bearings 24a and 24b in a left and right two-part split case 23.

The pedaling force transmission device 41 is a one-way clutch 6 that transmits only the forward rotation of the crankshaft 13.
A primary sun gear (input gear) 42 mounted on the crankshaft 13 via an arm 3, an arm 45 rotatably supported by the crankshaft 13, and an arm 45 rotatably supported by the arm 45. Primary planetary gear 4 meshing with sun gear 42
4, a secondary planetary gear 43 that rotates integrally with the primary planetary gear 44 and meshes with a secondary sun gear 32 rotatably mounted on the crankshaft 13, and a boss portion 32a of the secondary sun gear 32. And a fixed crank sprocket 15. The crank sprocket 15 is a chain 20
Is connected to the free wheel sprocket 21 of the rear wheel 8 via. The freewheel sprocket 21 is
It has a one-way clutch that transmits only forward power from the chain 20 to the rear wheels 8.

The electric power drive system 9b is a motor 12 fixed to a rear portion of the crankshaft 13 of the case 23 by a bolt 25, and a reduction mechanism 31 for decelerating rotation of the motor 12 and transmitting the decelerated rotation to the human power drive system 9a. It has and. The amount of power supplied from the battery 10 to the motor 12 is controlled by the controller 11, which allows the human power drive system 9 to operate.
The assisting force to a is controlled.

The rotation shaft 26 of the motor 12 and the reduction shaft 60 of the reduction mechanism 31 are arranged in parallel with the crankshaft 13. At this time, the battery 10 is mounted on the vehicle body, and at the same time, the battery 10 is connected to the motor 12 via the connectors 10a and 10b, so that a power supply harness between the two is unnecessary.

The motor 12 includes a magnet 34 attached to a motor case 33, an armature winding 35 wound around a rotating shaft 26 of the motor 12, and a commutator attached to one end of the rotating shaft 26. 36 and a brush 37 for supplying power to the armature winding 35 via the commutator 36, and the rotary shaft 26 is rotatably supported by the case 33 by bearings 38 and 39. .

The deceleration mechanism 31 transfers the primary small gear 27 mounted on the rotary shaft (output shaft) 26 of the motor 12 to the left end of the deceleration shaft 60 only from the motor 12 in the direction of the deceleration shaft 60. The secondary small gear 29 formed at the right end of the reduction shaft 60 is meshed with the primary large gear 28 mounted via the directional clutch 68, and the secondary sun gear 3
The secondary gear 3 splined to the boss 32a of the second gear 3
It is configured to be meshed with 0. The reduction shaft 60 is rotatably supported by the case 23 via bearings 61 and 62.

Since the secondary large gear 30 has a large diameter, a large empty space is formed in front of the crankshaft 13, and the controller 11 is housed in this empty space. Reference numeral 23a is a lid that covers the opening of the controller storage chamber.

As shown by the broken line in FIG. 3, a pedal effort detecting device 40 is arranged between the primary and secondary large gears 28 and 30 of the electric power drive system. The detection device 40 includes an arm urging mechanism 46 that urges the arm 45 in a direction to prevent the arm 45 from rotating, and a potentiometer (rotation amount) that detects the amount of rotation of the arm 45 that rotates against the urging force. (Detection means) 47 and the controller (assist force control means) 11 that calculates the input pedal force from the detection value of the potentiometer 47.

The arm urging mechanism 46 is provided in the case 2
A rod 48b is slidably inserted into a cylinder 48a fixed to the shaft 3, and a spring 48c is provided between the rod 48b and the cylinder 48a.
b contacts the connecting pin 45a fixed between the left and right arms 45, 45, thereby urging the arm 45 in the clockwise direction in FIG.

The potentiometer 47 has a slider 47b in a casing 47a fixed to the case 23.
The slider 47b is in contact with the lower connecting pin 45b of the arm 45, and the slider 47b moves in and out according to the rotation of the connecting pin 45.

Here, the principle of pedaling force detection in the present embodiment will be described with reference to FIGS. 4 and 5 which schematically show the pedaling force transmitting device 41. 4 and 5, the number of teeth of the sun gear (input gear) 42 is A, and the primary and secondary planetary gears 4 are
Number of teeth of 4, 43 is C, D, secondary sun gear (output gear) 3
When the number of teeth of 2 is E, the crankshaft 13 and the arm 4 are
5. The rotation speed of the crank sprocket 15 shows the characteristics shown in Table 1.

[0024]

[Table 1]

From the table, when the crankshaft 13 is used as a reference, the speed increasing ratio (iE) of the crank sprocket 15 = A.D /
Speed increase ratio of C / E arm 45 (iB) = 1 / (1-C / E / A /
D) and therefore the torque (TB) required to fix the arm 45 = 1-
C / E / A / D.

For example, if the number of teeth of each gear is A = 21,
When C = 12, D = 14, and E = 19 are set, from the above equations, iE = 1.2895 TB = 0.2245 iB = 4.4545. The fixed torque of the arm 45 (TB =
0.2245) is a manual torque (1.0) to the crank shaft 13 and a transmission torque (1 to the crank gear 15).
/IE=1/1.2895). With the above number of teeth, the force acting on the spring 48c by the fixed torque is about 28 kg when the pedal force is 40 kg, the crank radius is 165 mm, and the arm radius is 52.3 mm. From these, it can be understood that the pedaling force input to the crankshaft 13 can be detected by appropriately setting the spring constant of the spring 48c, the stroke of the potentiometer, and the like.

Next, the operation of the power assisted bicycle 1 according to this embodiment will be described mainly with reference to FIG.

When the pedal effort of the occupant is applied to the pedal 17, the pedal effort is applied to the crankshaft 13 and the one-way clutch 63.
Is transmitted to the primary sun gear (input gear) 42, and the rotation of the primary sun gear 42 is accelerated by the primary and secondary planetary gears 44 and 43 and the secondary sun gear 32, and the rotation of the crank sprocket 15 is increased. It is transmitted to the rear wheel 8 via the freewheel sprocket 21.

In this case, a fixed torque according to the pedaling force acts on the arm 45, and the spring 48c contracts according to the fixed torque, and the arm 45 is contracted by the contraction.
Is detected by the potentiometer 47,
Based on the detected value, the pedal force of the occupant is calculated by the controller (pedal pedal force calculating means) 11, and the output of the motor 12 is controlled based on the calculated pedal force.

The rotation of the motor 12 is transmitted to the boss portion 32a through the primary small gear 27, the primary large gear 28, the secondary small gear 29, and the secondary large gear 30, and the crank sprocket 15 and the rear wheel. 8 will be supplied with auxiliary power.

Thus, in this embodiment, the arm 45
Is supported by the crankshaft 13 and the arm 45
Since the pedal depression force is detected based on the rotation amount of, the number of parts can be reduced and the installation space can be reduced as compared with the conventional one in which the depression force is detected from the rotation angle of the sun gear.

Further, since the urging mechanism 46 and the potentiometer 47 are arranged between the primary and secondary large gears 28 and 30, the pedaling force detecting device 40 can be arranged by utilizing the empty space.

Further, the motor shaft 26 and the reduction shaft 60 are arranged in parallel with the crank shaft 13, the primary large gear 28 and the secondary small gear 29 are arranged at both ends of the reduction shaft 60, and the crank shaft 13 is the secondary large gear. Since 30 is pivotally supported, the entire apparatus can be downsized, and an empty space is created in front of the crankshaft 13, so that the control unit 11 and the like can be easily arranged.

Next, the second aspect of the present invention will be described with reference to FIGS.
A power assisted bicycle according to the embodiment will be described. Figure 6
Is a side view of a main part, and FIG. 7 is a cross-sectional view of the main part. The same reference numerals as those in FIGS. 1 to 3 denote the same or corresponding parts. The present embodiment is an example in which the main part of the above-mentioned drive device is arranged in the hub 21 of the rear wheel 8.

In the figure, reference numeral 64 designates the rear wheel 8 as a bearing 6
The support shaft 64 is rotatably supported via 5, 66. The support shaft 64 is fixedly supported by the connecting portion between the chain stay 2d and the seat stay 2e.

In the manual drive system, the rotation of the crankshaft is transmitted from the crank sprocket fixed to the crankshaft to the sprocket 20 via the chain, and the rotary shaft 32b to which the sprocket 20 is fixed makes the rotation of the primary sun gear 42, the primary sun, the secondary sun. It is transmitted to the next planetary gears 44, 43 and the secondary sun gear 32 via the one-way clutch 63 to the rear wheel 8 fixed to the boss portion 32a.

In the electric power drive system, the rotation of the motor rotating shaft 26 is performed by rotating the primary small gear 27, the large gear 28, and the secondary small gear 2.
9, transmitted from the secondary gear 30 to the rear wheel 8 via the boss portion 32a.

A biasing mechanism 46 is arranged on the front side of the upper part of the arm 45, and a potentiometer 47 is arranged on the rear side of the upper part.

As described above, also in the second embodiment, the same effect as that of the first embodiment can be obtained. In this case, since the pedal effort detection device 40 is provided on the upper side and the primary and secondary large gears 28, 30 are provided on the same side, a space A is created between the reduction shaft 60 and the support shaft 64, and the space A In-vehicle parts such as a controller can be placed in the.

[0040]

According to the power-assisted vehicle of the first aspect of the present invention, which is a component of the planetary gear train, the arm pivotally supported by the rotating shaft is biased in the counter-rotating direction, and the arm is attached. Since the pedal depression force is detected based on the amount of rotation that rotates against the force, the conventional sun gear is provided with an arm portion dedicated to torque detection, and a lever that abuts against this arm portion is pivotally supported. The number of parts can be reduced and the space for installation can be reduced as compared with the case of the conventional one.

According to the power assisted vehicle of the second aspect of the present invention, the motor of the electric power drive system and the reduction shaft are arranged in parallel with the rotation shaft, and one end of the reduction shaft engages with the primary small gear of the motor output shaft. Since the gear has a structure in which the secondary small gear that meshes with the secondary large gear of the rotary shaft is provided at the other end, the human power drive system and the power drive system can be compactly integrated, and the entire drive device can be made compact. There is an effect that can be converted.
Further, in this case, an empty space is generated in the area of the crankshaft direction projection surface of the secondary large gear, and the control unit or the like can be mounted.

According to the power assisted vehicle of the third aspect of the present invention, the arm urging means and the rotation amount detecting means are arranged between the primary and secondary large gears of the electric power drive system. A pedaling force detecting means can be arranged, and there is an effect that the entire apparatus can be downsized.

[Brief description of drawings]

FIG. 1 is a schematic side view of a power-assisted bicycle according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional plan view of a main part of the bicycle according to the first embodiment.

FIG. 3 is a sectional view taken along line III-III of FIG. 2;

FIG. 4 is a schematic side view for explaining a pedaling force detection principle of the bicycle according to the first embodiment.

FIG. 5 is a schematic plan view for explaining the pedaling force detection principle of the bicycle according to the first embodiment.

FIG. 6 is a side view of a main part of a power assisted bicycle according to a second embodiment of the present invention.

FIG. 7 is a rear development view of a cross section of a main part of the bicycle according to the second embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Power assisted vehicle 11 Controller (assist force control means, pedal depression force calculation means) 12 Motor 13 Crankshaft (rotary shaft) 26 Motor output shaft 27 Primary small gear 28 Primary large gear 29 Secondary small gear 30 Secondary large gear 32b Rotation Axis 40 Pedal pedal force detection device 41 Pedal force transmission device (planetary gear train) 42 Input gear (sun gear) 44 Planetary gear 45 Arm 47 Potentiometer (rotation amount detection means) 48 Spring (arm urging means) 60 Reduction shaft

Claims (3)

[Claims] 1. A human power drive system for outputting pedal power via a planetary gear train, an electric power drive system provided in parallel with the human power drive system, and pedal power detection means for detecting pedal power of the human power drive system. In a power assisted vehicle including: an assist force control unit that controls the output of the electric power drive system according to the detected pedal effort, the planetary gear train includes a sun gear provided on a rotating shaft; An arm rotatably supported on the rotating shaft and a planetary gear rotatably supported on the arm are provided, and the pedal depression force detecting means moves the arm in a direction to prevent the arm from rotating. A power assist, comprising arm urging means for urging, rotation amount detecting means for detecting a rotation amount of the arm, and pedal stepping force calculating means for calculating the pedaling force based on the detected value. vehicle. 2. The electric power drive system according to claim 1,
The motor and the reduction shaft are arranged in parallel with the rotation shaft, the primary small gear of the motor output shaft meshes with the primary large gear at one end of the reduction shaft, and the secondary small gear at the other end of the reduction shaft rotates the rotation shaft. A power-assisted vehicle characterized by being configured to mesh with a secondary large gear serving as a center. 3. The power assist vehicle according to claim 2, wherein the arm urging means and the rotation amount detecting means are arranged between the primary and secondary large gears of the electric power drive system.