JP3614901B2 - Power assist bicycle - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a power assist bicycle in which an auxiliary driving force corresponding to the pedaling force of a pedal is supplied to a rear wheel by a motor.
[0002]
[Prior art]
For example, when a bicycle runs on an uphill, in a headwind, or with a load loaded, a large pedal effort is required. In order to reduce such a burden at the time of traveling, a power assist bicycle equipped with a power assist unit that provides an auxiliary driving force in accordance with the pedaling force of a pedal has been proposed (see, for example, Japanese Patent Laid-Open No. 6-211179). ). The power assist unit includes a motor that rotationally drives the rear wheels, a battery that supplies power to the motor, and a controller that controls the driving force of the motor in accordance with the torque applied to the pedal and the vehicle speed.
[0003]
The power assist bicycle is provided with a warning display device for displaying a warning about a battery voltage drop and a system abnormality. This warning display device includes one common warning lamp. The warning lamp starts blinking when the battery voltage drops below a predetermined value, and when the battery voltage drops below a predetermined voltage lower than the predetermined value. It is configured to continuously light up, and when an abnormality of the power assist system is detected by the self-diagnosis function of the controller, it is configured to blink with a pattern according to the abnormality content. In the conventional warning display device, when an abnormality occurs in the system when the warning lamp displays the battery voltage drop, it is common to continuously display the voltage drop.
[0004]
[Problems to be solved by the invention]
By the way, the conventional power assist bicycle has a problem that the warning display and the system state do not always coincide with each other because the flashing display of the voltage drop continues when the system abnormality occurs during the battery voltage drop flashing. That is, although the controller is stopped due to system abnormality, the user may misunderstand that it is merely a voltage drop, and there is a problem that the discovery of the failure is delayed accordingly.
[0005]
Some system abnormalities can be found only when the battery voltage is low, but it is difficult to find this kind of abnormality as long as the voltage drop warning display is continued.
[0006]
The present invention has been made in view of the above-described conventional situation, and an object of the present invention is to provide a power assist bicycle that can match a warning display and a system state and can detect an abnormality of the power assist system at an early stage.
[0007]
[Means for Solving the Problems]
The present invention relates to a power assist bicycle including a power assist unit including a motor that rotationally drives a wheel, a battery that supplies power to the motor, and a controller that controls the driving force of the motor according to a pedaling force. Voltage detection means for detecting the voltage, failure diagnosis means for self-diagnosis of the presence or absence of a system abnormality, warning display control means for performing a voltage drop warning display or a fault warning display when a voltage drop signal or a fault signal is input, An abnormality warning priority display means is provided for preferentially displaying a failure warning display when the voltage drop signal and the failure signal are input in duplicate.
[0008]
[Action]
According to the power assist bicycle according to the present invention, if an abnormality occurs in the power assist system while the battery voltage drop is displayed, the system abnormality is preferentially switched and displayed, so that the system state and the warning state are matched. System abnormality can be detected early. In addition, when a system abnormality occurs due to a drop in battery voltage, the system abnormality is displayed with priority, so it is possible to identify components or circuit elements that show an abnormal mode only when the voltage drops. Become.
[0009]
【Example】
Embodiments of the present invention will be described below with reference to the accompanying drawings.
1 to 8 are views for explaining a power assist tricycle according to an embodiment of the present invention. FIGS. 1 and 2 are a side view and a plan view of the power assist tricycle, respectively, and FIG. 3 is a pedal. FIG. 4 is a sectional side view showing the swinging part of the front frame, FIG. 5 is a sectional view taken along the line V-V of FIG. 4, FIGS. 6 and 7 are block configuration diagrams, and FIG. It is a flowchart figure which shows operation | movement.
[0010]
In the figure, reference numeral 1 denotes a power-assisted three-wheel bicycle according to the present embodiment. A body frame 2 of the three-wheel bicycle 1 swings a rear end portion 4a of a front frame 4 extending rearward and downward from a head pipe 3 to a rear frame 5. The seat tube 6 is movably connected and has a structure in which a seat tube 6 on which a saddle 6a on which an occupant is seated is erected at a substantially central portion in the longitudinal direction of the front frame 4.
[0011]
A steering shaft 8a of the front fork 8 is pivotally supported by the head pipe 3, a front wheel 9 is pivotally supported at the lower end of the front fork 8, and a handle 10 is fixed to the upper end. A front basket 11 is attached to the fork 8 via a bracket.
[0012]
The rear frame 5 is formed by connecting a lower frame 15 having a generally U-shape in plan view and an upper frame 16 having a generally rectangular shape in plan view disposed in parallel thereabove by four reinforcing frames 17. The left and right sides of the upper frame 16 are bent downward in a V shape so that the bearing portion 16a is integrally formed. A reinforcing plate 18 extending in the vehicle width direction is bridged and joined to the lower frame 15, and two reinforcing plates 19, 19 extending in the longitudinal direction of the vehicle body are bridged and joined to the upper frame 16. . A rear basket 20 is placed on the upper surface of the upper frame 16, and the rear basket 20 is fixed to the reinforcing frame 19 with bolts.
[0013]
As shown in FIGS. 4 and 5, a swing shaft 22 is fixed to the rear end portion 4 a of the front frame 4 via a pair of brackets 21 and 21. The oscillating shaft 22 has a cylindrical shape at both ends 22a and a square column at the center 22b. The both ends 22a are rotatably supported by the reinforcing plate 18 via bearings 18a. The rocking shaft 22 is fitted with a rectangular tube-shaped bearing pipe 23 fixed on the reinforcing plate 18, and a knight hart rubber 24 is disposed between the bearing pipe 23 and the rocking shaft 22. ing. As a result, the front frame 4 can swing left and right, and is returned to its original vertical position by the elastic force of the Knighthard rubber 24.
[0014]
Rear wheels 30, 30 are disposed on the left and right outer portions of the rear frame 5. The axle 30a of the rear wheel 30 is pivoted by the left and right bearing portions 16a of the upper frame 16 and the bearing portions of the lower frame 15, respectively. It is supported.
[0015]
As shown in FIG. 3, a driven sprocket 32 is coupled to the inner ends of the two axles 30a with a one-way clutch 31 interposed therebetween. An intermediate shaft 33 is disposed in front of both axles 30a in parallel with the axle 30a. The intermediate shaft 33 is rotatably supported by the lower frame 15 via a bearing (not shown). Drive sprockets 34 and 35 are coupled to both ends of the intermediate shaft 33, and the sprockets 34 and 35 are connected to the drive sprockets 32 and 32 via chains 37 and 37, respectively.
[0016]
A support boss 4b is formed at the base of the seat tube 6 of the front frame 4, and a pedal shaft 40 is rotatably attached to the boss 4b. Pedals 42 are attached to both ends of the pedal shaft 40 via cranks 41. The driving force of the pedal shaft 40 is transmitted to the intermediate shaft 33 through the driving sprocket 43, the chain 44, and the driven sprocket 36 from the resultant force shaft 49a of the planetary gear type transmission 49 through the one-way clutch 80. In this embodiment, the power from the pedal 42 is transmitted simultaneously to the left and right rear wheels 30 via the intermediate shaft 33. Therefore, the one-way clutch 31 absorbs the rotational difference between the two wheels during turning. Become.
[0017]
The vehicle body frame 2 is provided with the power assist unit 50 of the present embodiment. The power assist unit 50 includes a motor 51 that rotationally drives both rear wheels 30 via a pedal shaft 40, a battery 52 that supplies power to the motor 51, and a controller 53 that controls the driving force of the motor 51. A torque sensor 54 and a vehicle speed sensor 55 are connected to the controller 53. A warning lamp 56 is attached to the base of the seat tube 6 of the front frame 4, and the display content of the warning lamp 56 is controlled by the controller 53.
[0018]
The torque sensor 54 detects a reaction force acting on a fixed element in the planetary gear type transmission 49 as a torque, and outputs the detected value to the controller 53. The vehicle speed sensor 55 is configured to detect the peripheral speed of the bevel gear 49 b fixed to the resultant force shaft 49 a of the transmission 49 and output the detected value to the controller 53.
[0019]
The battery 52 is a 12V battery, and is connected in series with each other in the vertical direction, and is housed in a rectangular parallelepiped battery box 60 that is long in the vertical direction. The battery box 60 is vertically disposed on the front frame 4 on the rear side of the seat tube 6, and has a rectangular frame-like support pipe 62 joined to the seat tube 6 and the support pipe 62. It is supported by a support pipe 63 that is bridged and joined to the front frame 4. The rear portion of the support pipe 62 and the front frame 4 are joined together by a reinforcing pipe 64 that extends obliquely rearward. A handle 65 is attached to the upper surface of the battery box 60, and the battery box 60 can be pulled out by removing the saddle 6a. Although not shown, the battery box 60 is provided with a charging outlet.
[0020]
The motor 51 is disposed on the lower surface of the central portion of the front frame 4 and is fixed to the front frame 4 via a mounting bracket (not shown). The output of the motor 51 is input to the drive sprocket 43 from the resultant force shaft 49 a of the transmission mechanism 49 via the one-way clutch 39, and is transmitted to the left and right rear wheels 30 through the intermediate shaft 33.
[0021]
The controller 53 is disposed on the lower surface of the front frame 4 in front of the motor 51, and is fixed to the front frame 4 via a mounting bracket (not shown). Thus, the controller 53, the motor 51, and the speed change mechanism 49 are arranged in series along the lower surface of the front frame 4.
[0022]
The controller 53, the motor 51, and the speed change mechanism 49 are covered with a cover 75. The cover 75 has a two-part structure comprising an upper cover 75a fixed to the front frame 4 and a lower cover 75b removably attached to the lower surface of the upper cover 75a, thereby improving the appearance. At the same time, damage to each component is avoided. Further, a main key switch 75c for operating the power assist system is disposed at the front portion of the lower cover 75b.
[0023]
The controller 53 obtains the magnitude of the torque (depression force) generated in the pedal 42 from the detection value of the torque sensor 54, obtains the vehicle speed from the detection value of the vehicle speed sensor 55, and based on the built-in map, the auxiliary driving force And a current corresponding to the auxiliary driving force is supplied from the battery 52 to the motor 51. This auxiliary driving force is set to be less than 1 with respect to the pedaling force 1 of the occupant and gradually decreases the auxiliary power when the vehicle speed exceeds, for example, 15 km / h, and becomes zero when the vehicle speed reaches 24 km / h. It is set to be.
[0024]
The controller 53 also functions as battery voltage detection means 53a, power assist system failure diagnosis means 53b, warning display control means 53c, and failure warning priority display means 53d.
[0025]
The voltage detection means 53a determines whether the battery voltage is in a normal drop state or an abnormal drop state, and outputs a normal drop signal and an abnormal drop signal, respectively. When the main switch 75c is turned on, the failure diagnosing means 53b self-diagnose whether there is a system abnormality in the controller 53, and outputs a failure signal when the abnormality is found. The warning display control means 53c controls blinking and lighting of the warning lamp 56 in accordance with the contents of each signal. For example, in the case of the normal decrease signal, the warning lamp 56 blinks at regular intervals, and in the case of the abnormal decrease signal, it is continuously lit. In the case of a failure signal, it blinks with a pattern determined for each failure content.
[0026]
The failure warning priority display means 53d switches the voltage drop warning display to the failure warning display and displays it when either the normal or abnormal voltage drop signal and the failure signal are input in duplicate.
[0027]
Next, the function and effect of this embodiment will be described.
The power assist unit 50 of the present embodiment supplies a larger auxiliary driving force as the pedaling force of the occupant increases when the vehicle speed is a predetermined value (for example, 15 km / h) or less, and the speed increases when the speed exceeds the predetermined value. As the speed increases, the auxiliary driving force is decreased, and when the speed exceeds the maximum value (for example, 24 km / h), the auxiliary driving force is reduced to zero. In this way, labor can be reduced during uphill slopes, headwinds, loading, and starting. In addition, although the rotational force from the pedal shaft / motor shaft side to the rear wheel side is transmitted by each one-way clutch, the rotational force in the reverse direction is not transmitted.
[0028]
Further, as shown in the flowchart of FIG. 8, the controller 53 of this embodiment determines whether or not there is an abnormality in the power assist system. If there is an abnormality, the voltage drop warning process is canceled and the system abnormality display process is performed. Switching (steps S1, S2). When there is no abnormality in the system, the voltage detection value is read, and when the detection value is not more than a predetermined value, a voltage drop warning process is performed (steps S3 and S4).
[0029]
As described above, according to the present embodiment, when the voltage drop signal and the failure signal are input in duplicate, the failure warning is displayed with priority on the failure signal, so that the battery voltage is lowered. When a system abnormality occurs, it is possible to prevent a user from misinterpreting a control stop due to a system abnormality as a control stop due to a mere voltage drop, and a system failure can be detected early.
[0030]
Further, in this embodiment, since the failure warning display is prioritized, it is possible to deal with a case where an abnormality such as a Zener diode failure occurs in a system that can occur only when the battery voltage decreases. In the case of conventional voltage drop display priority, even if the Zener diode becomes abnormal, the battery voltage drop display is continued, so that it is difficult to find a failure of the Zener diode.
[0031]
In the above embodiment, the case where the power assist unit is mounted on the three-wheeled bicycle is taken as an example, but the present invention can also be applied to the two-wheeled bicycle.
[0032]
【The invention's effect】
As described above, the power assist bicycle according to the present invention includes the failure warning priority display means for giving priority to the failure warning display when the voltage drop signal and the failure signal are input in duplicate. And the system failure can be detected at an early stage.
[Brief description of the drawings]
FIG. 1 is a side view for explaining a power-assisted three-wheel bicycle according to an embodiment of the present invention.
FIG. 2 is a partial cross-sectional side view of the above-described three-wheeled bicycle.
FIG. 3 is a schematic configuration diagram showing a rear wheel drive mechanism of the three-wheel bicycle according to the embodiment.
FIG. 4 is a cross-sectional side view showing a swinging part of a front frame of the three-wheeled bicycle according to the embodiment.
5 is a cross-sectional view taken along line VV of FIG. 4 showing the swinging part.
FIG. 6 is a block diagram of the power assist unit of the embodiment.
FIG. 7 is a block diagram of the controller of the embodiment.
FIG. 8 is a flowchart showing the operation of the controller of the embodiment.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Power assist 3 wheel bicycle 2 Body frame 30 Rear wheel 50 Power assist unit 51 Motor 52 Battery 53 Controller 53a Battery voltage detection means 53b Failure diagnosis means 53c Warning lamp display means 54d Failure priority determination means

Claims (1)

A battery voltage is detected in a power assist bicycle having a power assist unit including a motor that rotationally drives a wheel, a battery that supplies power to the motor, and a controller that controls the driving force of the motor according to the pedaling force of the pedal. Voltage detection means, failure diagnosis means for self-diagnosis of system abnormality, warning display control means for displaying voltage drop warning or fault warning when a voltage drop signal or fault signal is input, and the voltage drop signal And an abnormality warning priority display means for preferentially displaying a failure warning display when failure signals are input in duplicate.

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