JP2008162374A - Driving force control device for electric-assisted bicycle, and electric-assisted bicycle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the sense of incongruity to the vibrations during the travel felt by a rider of a bicycle. <P>SOLUTION: In a driving force control device 9, the vibration of a body frame 3 is detected by a three-axis acceleration sensor 32, and the detected vibration waveform of the body frame 3 is analyzed by a waveform analysis unit 33. The waveform of the opposite phase to that of the vibration waveform of the body frame 3 obtained by the analysis is generated by a waveform generation unit 34, and the waveform of the opposite phase generated by the waveform generation unit 34 is generated by an electric motor 31 for generating an auxiliary driving force. The waveform having the opposite phase to that of the vibration generated in the body frame 3 is generated, and canceled by the interference with the body frame to reduce rider's sense of incongruity to the vibration during the travel felt. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an electrically assisted bicycle that travels in a forward direction by electric power driving in addition to human power driving, and an electrically assisted bicycle driving force control device that rotates a rear wheel of the electrically assisted bicycle.

  Bicycles are affected by road surface irregularities as they travel, causing vibrations in the body frame, but the structure for absorbing this vibration is generally the suspension provided on tires, saddles, etc. Is. In addition, there is no exception in so-called electrically assisted bicycles, which are becoming popular in recent years, in which an electric motor is driven during driving to drive the electric motor in addition to driving manually. Even though the electric assist bicycle reduces the load on the rider by the assist function compared to a normal bicycle, the vibration absorption performance is not high, so it cannot be denied that the rider feels uncomfortable when driving. .

For example, in the field of so-called hybrid vehicles in which an electric motor or a generator is mounted together with an internal combustion engine, a technique has been proposed that cancels out torque vibrations of the engine by outputting reverse-phase torque from the electric motor (for example, Patent Documents). 1, see Patent Document 2).
Japanese Patent No. 3801146 JP 2006-67655 A

  However, in the general bicycle and the electric assist bicycle described above, the vibration absorption capacity is low at the degree of suspension provided on a tire, saddle, etc., and the suspension structure is enhanced as seen in automobiles, motorcycles, etc. Since dealing with this causes an increase in cost, it can be applied only to some high-performance bicycles. In addition, while power-assisted bicycles require only a basic configuration to reduce weight, enriching the structure for absorbing vibration also leads to a significant increase in weight. There was a problem that it was difficult to improve the handling of the bicycle.

  Therefore, the present invention has been proposed in view of the above-described conventional situation, and an electrically assisted bicycle driving force control device and an electrically assisted bicycle capable of reducing a sense of incongruity with respect to vibrations during traveling felt by a bicycle rider. The purpose is to provide a bicycle.

  In order to achieve the above-described object, a driving force control apparatus for an electrically assisted bicycle according to claim 1 of the present invention generates an auxiliary electric power drive in conjunction with a human power drive and travels in a forward direction. In a driving force control device for a motor, an electric motor for generating an auxiliary driving force, a vibration detecting means for detecting vibration of the vehicle body frame, and a waveform analysis for analyzing a vibration waveform of the vehicle body frame detected by the vibration detecting means Means, a waveform generating means for generating a waveform having an opposite phase to the vibration waveform of the vehicle body frame obtained by analysis, and a drive control means for controlling the driving of the electric motor so as to generate the generated waveform. It is characterized by.

  According to a first aspect of the present invention, there is provided a driving force control apparatus for an electrically assisted bicycle that detects vibrations of a vehicle body frame by vibration detection means, and analyzes and analyzes the detected vibration waveforms of the vehicle body frame by waveform analysis means. A waveform having a phase opposite to the vibration waveform of the vehicle body frame is generated by the waveform generation unit, and the waveform having the opposite phase generated by the waveform generation unit is generated by an electric motor that generates an auxiliary driving force.

  Therefore, according to the invention described in claim 1 of the present invention, a waveform having an antiphase of vibration generated in the body frame is generated by the electric motor and is canceled by interference with the body frame, thereby It is possible to reduce a sense of incongruity with respect to vibration during traveling.

  According to a second aspect of the present invention, there is provided an electric assist bicycle driving force control device comprising motor torque detection means for detecting the torque of the electric motor, wherein the drive control means has a torque detected by the motor torque detection means. When 0, the electric motor is driven in the direction opposite to that in the forward direction so as to generate the generated waveform.

  According to a second aspect of the present invention, when the torque of the electric motor detected by the motor torque detecting means is zero, the electric assist bicycle driving force control device according to the second aspect of the present invention electrically drives a waveform having a reverse phase of vibration generated in the body frame. By generating by the motor and causing the body frame to interfere and cancel, it is possible to reduce a sense of incongruity with respect to the vibration during traveling that is felt by the rider of the bicycle.

  In order to achieve the above-described object, an electrically assisted bicycle according to claim 3 of the present invention includes an electric motor that generates an auxiliary driving force, vibration detection means that detects vibration of the body frame, vibration A vibration analyzing means for analyzing the vibration of the vehicle body frame detected by the detecting means; a waveform generating means for generating a waveform having an opposite phase to the vibration waveform of the vehicle body frame obtained by the analysis; and generating the generated waveform And a drive control means for controlling the drive of the electric motor.

  In the electrically assisted bicycle according to claim 3 of the present invention, the vibration of the vehicle body frame is detected by the control device, the detected vibration waveform of the vehicle body frame is analyzed, and the vibration waveform of the vehicle body frame obtained by the analysis is opposite in phase. Are generated, and the generated anti-phase waveform is generated by the electric motor.

  Therefore, according to the invention described in claim 3 of the present invention, a waveform having an opposite phase of vibration generated in the vehicle body frame is generated by the electric motor and is canceled by interference with the vehicle body frame. It is possible to reduce a sense of incongruity with respect to vibration during traveling.

  ADVANTAGE OF THE INVENTION According to this invention, the discomfort with respect to the vibration at the time of the driving | running | working which the rider of a bicycle can feel can be reduced.

  Hereinafter, an electrically assisted bicycle and its control device shown as embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 shows a side appearance of the electrically assisted bicycle. In the figure, “F” indicates the forward direction, and “R” indicates the backward direction.

  As shown in FIG. 1, an electrically assisted bicycle 1 shown as an embodiment of the present invention is a bicycle that travels in the forward direction by electric power driving in addition to human power driving, and includes a body frame 3 as a base. . A front wheel 5 is rotatably provided at the front portion of the vehicle body frame 3, and a rear wheel 7 is rotatably provided at the rear portion of the vehicle body frame 3. The hanger portion 3a of the vehicle body frame 3 is provided with a driving force control device 9 for auxiliary rotation of the rear wheel 7.

  The driving force control device 9 is provided with a pedal crankshaft rotatably via a bearing. In addition, the pedal 11 is eccentrically attached to both ends of the pedal crankshaft via the crank 15, respectively. A circular drive plate 17 is concentrically provided on the pedal crankshaft via a one-way clutch (also referred to as a one-way clutch) (not shown). The one-way clutch connects the pedal crankshaft and the drive plate 17 only when the pedal crankshaft rotates in one direction (clockwise direction in FIG. 1, rotation direction when the bicycle travels in the F direction). Is. In addition, a winding portion capable of winding an endless belt (power transmission member) 19 that transmits a rotational force to the rear wheel 7 is formed on the outer edge portion of the drive plate 17. The belt 19 is also wound around a rear wheel pulley 21 provided concentrically on the rear wheel 7. Further, a battery 23 for supplying power to the driving force control device 9 is provided. The battery 23 is detachable from the vehicle body frame 3 and can be charged and used.

  Next, an example of the configuration of the driving force control device 9 will be described with reference to FIG. The driving force control device 9 mainly includes an electric motor 31 for generating auxiliary driving force, a triaxial acceleration sensor 32 as vibration detecting means for detecting vibration of the vehicle body frame 3, and a motor for detecting motor torque. A torque detection sensor 37 and a motor rotation speed detection sensor 38 are provided, and are controlled by a controller 30 that controls driving of the electric motor 31 based on detection results of various sensors.

  The electric motor 31 is a device that generates auxiliary power drive in conjunction with human power drive in which the rider steps on the pedal 11.

  The triaxial acceleration sensor 32 is a sensor that detects lateral (left-right) acceleration and longitudinal acceleration, and is used as vibration detection means that detects vibration of the vehicle body frame 3. The triaxial acceleration sensor 32 is provided at an appropriate position on the vehicle body frame 3.

  The controller 30 is electrically connected to the above-described three-axis acceleration sensor 32, a motor torque detection sensor 37, and a motor rotation speed detection sensor 38. The controller 30 also includes a ROM (not shown) that stores a motor control program for controlling the electric motor 31, and a CPU (not shown) that reads the motor control program stored in the ROM and executes motor control. (Not shown) and a RAM (not shown) for providing a work area for the CPU. The controller 30 also has a function as a waveform analysis unit 33, a function as a waveform generation unit 34, a function as a motor torque command value calculation unit 35, and a function as a motor control unit 36. Details of each function are as follows.

  The waveform analysis unit 33 analyzes the vibration waveform of the vehicle body frame 3 detected by the triaxial acceleration sensor 32 as vibration detection means, and supplies the analysis result to the waveform generation unit 34.

  The waveform generation unit 34 generates a waveform having an opposite phase to the vibration waveform of the vehicle body frame 3 supplied from the waveform analysis unit 33, and sends a signal for generating the generated reverse phase waveform to the motor torque command value calculation unit 35. Supply.

  The motor torque command value calculation unit 35 specifies a torque of the electric motor 31 based on a signal generated by the waveform generation unit 34 to generate a waveform having a phase opposite to the vibration waveform of the vehicle body frame 3. The value TP is calculated.

  The motor control unit 36 controls the electric motor 31 based on the motor torque command value TP calculated by the motor torque command value calculation unit 37. More specifically, the motor control unit 36 controls the current value supplied to the electric motor 31.

  The controller 30 is connected to a motor torque detection sensor 37 and a motor rotation speed detection sensor. As more specific control, the motor torque command value calculation unit 35 is opposite to the vibration waveform of the vehicle body frame 3 generated by the waveform generation unit 34 when the motor torque detected by the motor torque detection sensor 37 is zero. A signal for generating the phase waveform by driving the electric motor 31 in a direction opposite to that in the forward driving direction and a motor torque command value TP for designating the torque in the reverse direction at this time are calculated.

  Next, a series of vibration control operations by the CPU in the controller 30 will be described with reference to FIG. It is assumed that a series of motor control processes by the CPU in the controller 30 is executed every predetermined cycle (for example, 4 msec).

  First, the CPU in the controller 30 executes input signal detection processing for various detection sensors (step S1). Specifically, the vibration of the vehicle body frame is detected by the triaxial acceleration sensor 32, the rotational speed of the motor is detected by the motor rotational speed detection sensor 38, and the motor torque is detected by the motor torque detection sensor 37. The vehicle speed of the electrically assisted bicycle can be obtained from the rotation speed of the motor, and the stepping load on the rider's pedal 11 can be obtained from the motor torque.

  Next, the CPU in the controller 30 determines whether or not the motor torque is 0 (step S2). If the motor torque is not 0 (step S2: NO), the process is repeated from step S1. If the motor torque is 0 (step S2: YES), in step S3, based on the detection result from the triaxial acceleration sensor 32, the controller 30 determines whether the vibration of the vehicle body frame 3 is equal to or greater than a predetermined threshold value. Determine. That is, if the detection signal in the triaxial acceleration sensor 32 exceeds a predetermined threshold value, it is repeated from the step S1 on the assumption that the vibration damping operation is not necessary. On the other hand, if the detection signal in the triaxial acceleration sensor 32 does not exceed the threshold value, a vibration damping operation is performed. Therefore, in the present embodiment, the CPU in the controller 30 does not perform the vibration suppression operation for the sudden vibration having the amplitude exceeding the predetermined threshold value, and performs the vibration suppression operation for the continuous vibration. It has become. In this embodiment, it is determined in step S2 whether or not the motor torque is 0, but the motor torque threshold may not be 0. That is, the setting may be such that the vibration control operation is performed at times other than complete no-load.

  The CPU in the controller 30 analyzes the vibration waveform of the vehicle body frame 3 detected by the triaxial acceleration sensor 32 in step S4. Subsequently, in step S <b> 5, the CPU in the controller 30 generates a waveform having an opposite phase to the vibration waveform of the vehicle body frame 3 analyzed by the waveform analysis unit 33. In step S <b> 6, the CPU in the controller 30 supplies a signal for generating the generated reverse phase waveform to the motor torque command value calculation unit 35. The CPU in the controller 30 designates the torque of the electric motor 31 based on the signal generated by the waveform generation unit 34 for generating a waveform having a phase opposite to the vibration waveform of the vehicle body frame 3 in the subsequent step S7. A torque command value TP is calculated and supplied to the motor control unit 36.

  In particular, when the motor torque detected by the motor torque detection sensor 37 is 0, the motor torque command value calculation unit 35 generates a waveform having a phase opposite to the vibration waveform of the vehicle body frame 3 generated by the waveform generation unit 34. A motor torque command value TP that is generated by driving the electric motor 31 in the direction opposite to that when driving in the forward direction is calculated. That is, in the present embodiment, when the load is not applied to the pedal 11 (or when there is no load), the electric motor 31 is driven in the reverse direction to perform the vibration damping operation. When the electric motor 31 is driven based on the motor torque command value TP, vibration having the generated waveform can be generated.

FIG. 4 shows an example of a vibration waveform (f _in : thin solid line) of the vehicle body frame 3 detected by the triaxial acceleration sensor 32 and an anti-phase waveform (f _out : thick solid line) generated after analyzing the waveform. Indicates. Actually, since there is a time lag for calculating the waveform of the antiphase, a predicted waveform pattern is prepared, and when a predetermined detection signal pattern is detected by the triaxial acceleration sensor 32, a waveform prepared in advance is used. The motor torque command value TP to be generated may be supplied to the motor control unit. Alternatively, the controller 30 may always accumulate vibration waveform data in a RAM or the like and calculate a new predicted waveform pattern.

  As described above, in the driving force control device 9 shown as the embodiment of the present invention, the vibration of the vehicle body frame 3 is detected, and the detected vibration waveform of the vehicle body frame 3 is analyzed and analyzed by the waveform analysis unit 33. A waveform having a phase opposite to that of the obtained body frame 3 is generated by the waveform generator 34, and a motor torque command value for causing the electric motor 31 to generate the waveform having the opposite phase generated by the waveform generator 34 is calculated. The vibration generated by the electric motor and the vibration generated in the vehicle body frame can be made to interfere and cancel each other. Thereby, the uncomfortable feeling with respect to the vibration at the time of driving | running | working which the rider of a bicycle can feel can be reduced. Further, the driving force control device 9 detects the torque of the electric motor 31 and, when the torque is zero, drives the electric motor 31 in a direction opposite to that in the forward driving direction and has a phase opposite to that of the vibration of the vehicle body frame 3. By generating this vibration, it is possible to reduce the discomfort of the rider with respect to the vibration especially when the rider does not break the pedal and the bicycle is running.

  Moreover, since the electric assist bicycle 1 provided with the driving force control device 9 does not need to have a substantial structure for absorbing vibration, the weight can be reduced and the handleability of the electric assist bicycle can be improved.

  In addition, this invention is not restricted to description of embodiment mentioned above, In addition, it can implement in a various aspect. Further, the scope of rights encompassed by the present invention is not limited to these embodiments.

It is a side view explaining the electrically assisted bicycle shown as an embodiment of the present invention. It is a block diagram explaining the drive force control apparatus for electrically assisted bicycles shown as an embodiment of the present invention. It is a flowchart explaining the drive control in the said drive assist control apparatus for electric assist bicycles. It is explanatory drawing explaining the waveform of the reverse phase produced | generated in the drive control in the said drive assist control apparatus for electric assist bicycles.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electric assist bicycle 3 Body frame 3a Hanger part 5 Front wheel 7 Rear wheel 9 Driving force control apparatus for electric assist bicycles 11 Pedal 15 Crank 17 Drive plate 19 Belt (power transmission member)
DESCRIPTION OF SYMBOLS 21 Rear wheel pulley 23 Battery 31 Electric motor 32 3-axis acceleration sensor 33 Waveform analysis part 34 Waveform generation part 35 Motor torque command value calculation part 36 Motor control part 37 Motor torque detection sensor 38 Motor rotation speed detection sensor

Claims (3)

In a driving force control device for an electrically assisted bicycle that travels in the forward direction by generating auxiliary power driving in conjunction with human power driving,
An electric motor for generating the auxiliary driving force;
Vibration detecting means for detecting vibration of the body frame;
Waveform analysis means for analyzing the vibration waveform of the vehicle body frame detected by the vibration detection means;
A waveform generating means for generating a waveform having a phase opposite to that of the vibration of the vehicle body frame obtained by the analysis;
And a drive control means for controlling the drive of the electric motor so as to generate the generated waveform. Motor torque detecting means for detecting the torque of the electric motor;
When the torque detected by the motor torque detecting means is 0, the drive control means drives the electric motor in a direction opposite to the forward driving direction so as to generate the generated waveform. The driving force control apparatus for an electrically assisted bicycle according to claim 1, characterized in that: The electric motor for generating the auxiliary driving force; vibration detecting means for detecting vibration of the vehicle body frame; waveform analyzing means for analyzing the vibration waveform of the vehicle body frame detected by the vibration detecting means; Driving force control comprising: waveform generating means for generating a waveform having an opposite phase to the vibration waveform of the vehicle body frame obtained in the above; and drive control means for controlling the drive of the electric motor so as to generate the generated waveform Electric assist bicycle equipped with a device.

Images