Bicycle controller and bicycle control system including bicycle controller

1. A bicycle controller comprising:

an electronic control unit that controls a transmission unit, which is configured to change transmission ratio of a bicycle in a stepped manner, and that controls a motor, which assists propulsion of the bicycle, in accordance with a shift request that changes the transmission ratio,

the electronic control unit being configured to selectively execute one of a first shifting operation and a second shifting operation in a case in which the transmission ratio is changed in multiple steps in accordance with the shift request,

in the first shifting operation, the electronic control unit being configured to limit output of the motor and operates the transmission unit to reach a requested transmission ratio that corresponds to the shift request, and

in the second shifting operation, the electronic control unit being configured to limit the output of the motor and operate the transmission unit to reach an intermediate transmission ratio of the requested transmission ratio, and after the electronic control unit temporarily reduces the limit on the output of the motor, the electronic control unit again limits the output of the motor and operates the transmission unit.

2. The bicycle controller according to claim 1 , wherein

the electronic control unit is further configured to limit the output of the motor and starts to operate the transmission unit upon the electronic control unit receiving the shift request and a rotational angle of a crank of the bicycle reaching a first prescribed angle.

3. The bicycle controller according to claim 2 , wherein

the first prescribed angle is included in a range of 45 degrees from a first rotational angle corresponding to one of a top dead center and a bottom dead center of one of crank arms of the crank to an upstream side of the first rotational angle in a first direction in which the crank is rotated to propel the bicycle.

4. The bicycle controller according to claim 1 , wherein

in the second shifting operation, after the electronic control unit temporarily reduces the limit on the output of the motor, the electronic control unit is further configured to limit the output of the motor and starts to operate the transmission unit upon detecting a rotational angle of a crank of the bicycle reaching a prescribed angle.

5. The bicycle controller according to claim 4 , wherein

the prescribed angle is included in a range of 45 degrees from a second rotational angle corresponding to the other one of a top dead center and a bottom dead center of one of crank arms of the crank to an upstream side of the second rotational angle in a first direction.

6. The bicycle controller according to claim 2 , wherein

in the second shifting operation, after the electronic control unit temporarily reduces the limitation on the output of the motor, the electronic control unit is further configured to limit the output of the motor and starts to operate the transmission unit upon detecting the rotational angle of the crank of the bicycle reaching a second prescribed angle, and

the second prescribed angle is equal to the first prescribed angle.

7. The bicycle controller according to claim 2 , wherein

the electronic control unit is further configured to selectively execute one of the first shifting operation and the second shifting operation in accordance with the shift request that is received before the rotational angle of the crank reaches the first prescribed angle.

8. The bicycle controller according to claim 2 , wherein

the electronic control unit is further configured to limit the output of the motor until a first time elapses from a time that the rotational angle of the crank reaches the first prescribed angle.

9. The bicycle controller according to claim 2 , wherein

the electronic control unit is further configured to limit the output of the motor from a time that the rotational angle of the crank reaches the first prescribed angle until the rotational angle of the crank reaches a second prescribed angle.

10. The bicycle controller according to claim 1 , wherein

the electronic control unit is further configured to execute one of the first shifting operation and the second shifting operation in accordance with at least one of the number of steps in the transmission ratio to reach the requested transmission ratio and a shifting time that is required to move the transmission unit to the requested transmission ratio.

11. The bicycle controller according to claim 8 , wherein

the electronic control unit is further configured to execute one of the first shifting operation and the second shifting operation in accordance with a second time that is required to move the transmission unit to the requested transmission ratio,

in a case in which the first time is greater than or equal to the second time, the electronic control unit is further configured to execute the first shifting operation, and

in a case in which the first time is less than the second time, the electronic control unit is further configured to execute the second shifting operation.

12. The bicycle controller according to claim 9 , wherein

the electronic control unit is further configured to execute one of the first shifting operation and the second shifting operation in accordance with a shifting time that is required to move the transmission unit to the requested transmission ratio,

in a case in which an estimated time from a beginning time that the rotational angle of the crank reaches the first prescribed angle to an ending time that the rotational angle of the crank reaches the third prescribed angle is greater than or equal to the shifting time, the electronic control unit is further configured to execute the first shifting operation, and

in a case in which the estimated time is less than the shifting time, the electronic control unit is further configured to execute the second shifting operation.

13. A bicycle controller comprising:

an electronic control unit that operates a transmission unit, which is configured to change transmission ratio of a bicycle in a stepped manner, in accordance with a shift request that changes the transmission ratio,

the electronic control unit being configured to selectively execute one of a first shifting operation and a second shifting operation in a case in which the transmission ratio is changed in multiple steps in accordance with the shift request,

in the first shifting operation, the electronic control unit being configured to start to operate the transmission unit upon detecting a rotational angle of a crank of the bicycle reaching a first prescribed angle and operate the transmission unit until reaching a requested transmission ratio that corresponds to the shift request, and

in the second shifting operation, the electronic control unit being configured to start to operate the transmission unit upon detecting the rotational angle of the crank of the bicycle reaching the first prescribed angle and operate the transmission unit until reaching an intermediate transmission ratio of the requested transmission ratio, and then upon the rotational angle of the crank reaching a second prescribed angle, the electronic control unit being configured to resume operation of the transmission unit to change from the intermediate transmission ratio to the requested transmission ratio.

14. The bicycle controller according to claim 13 , wherein

the first prescribed angle is included in a range of 45 degrees from a first rotational angle corresponding to one of a top dead center and a bottom dead center of one of crank arms of the crank to an upstream side of the first rotational angle in a direction in which the crank is rotated to propel the bicycle.

15. The bicycle controller according to claim 14 , wherein

the second prescribed angle is included in a range of 45 degrees from a second rotational angle corresponding to the other one of the top dead center and the bottom dead center of the one of the crank arms to an upstream side of the second rotational angle in the first direction, or

the second prescribed angle is equal to the first prescribed angle.

16. The bicycle controller according to claim 14 , wherein

the electronic control unit is further configured to execute one of the first shifting operation and the second shifting operation in accordance with at least one of the number of steps in the requested transmission ratio and a shifting time that is required to move the transmission unit to the requested transmission ratio.

17. The bicycle controller according to claim 16 , wherein

the electronic control unit is further configured to execute the first shifting operation in a case in which a predetermined first time is greater than or equal to the shifting time, and

the electronic control unit is further configured to execute the second shifting operation in a case in which the predetermined first time is less than the shifting time.

18. The bicycle controller according to claim 1 , wherein

the electronic control unit is further configured to receive an output signal from an operation unit, which is operable by a rider, as the shift request.

19. The bicycle controller according to claim 18 , wherein

the electronic control unit is further configured to selectively execute one of the first shifting operation and the second shifting operation upon detecting the operation unit being continuously operated for a predetermined first period or the operation unit being operated multiple times within a second predetermined period.

20. A bicycle control system comprising:

the bicycle controller according to claim 18 ;

the transmission unit;

the motor; and

the operation unit.

21. A bicycle controller comprising:

an electronic control unit that controls a transmission unit, which is configured to change transmission ratio of a bicycle in a stepped manner, and that controls a motor, which assists propulsion of the bicycle, in accordance with a shift request that changes the transmission ratio,

upon the electronic control unit receiving the shift request, and a crank of the bicycle reaching a first prescribed angle, which is located at an upstream side of a rotational angle that corresponds to a top dead center or a bottom dead center in a first direction in which the crank is rotated to propel the bicycle, the electronic control unit being configured to limit output of the motor and start to operate the transmission unit, and

the electronic control unit being configured to change the first prescribed angle further to the upstream side in the first direction in a case in which the transmission unit changes the transmission ratio in multiple steps in accordance with the shift request from a case in which the transmission unit changes the transmission ratio in only one step.