Method and device for detecting wear on an electric bicycle

• US 9,514,576 B2
• Filed: 04/23/2012
• Issued: 12/06/2016
• Est. Priority Date: 06/08/2011
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Gerundt, Oliver, Dasbach, Gregor, Immendoerfer, Ingo, Diekmann, Ralf
• Primary Examiner(s): TRAN, KHOI H
• Assistant Examiner(s): Peche, Jorge
• Application Number:
  US14/123,852
• Publication Number:
  US 20140229054A1
• Time in Patent Office: 1,688 Days
• Field of Search: 701/29.1, 701/29.4
• US Class Current: 1/1
• CPC Class Codes: B62J 45/20 Cycle computers as cycle accessories
• CPC Class Codes: B62J 45/40 Sensor arrangements sensors for control of electrically assisted cycles B62M6/50; Mounting thereof
• CPC Class Codes: B62J 50/22 electronic, e.g. displays
• CPC Class Codes: B62M 6/50 characterised by detectors or sensors, or arrangement thereof
• CPC Class Codes: G07C 5/006 Indicating maintenance

Abstract

A method for detecting wear on at least one component of an electric bicycle includes: monitoring the operating condition of the at least one component with the aid of at least one sensor; detecting the stress on the component over the duration of operation; and displaying the need for service on a display unit as soon as a long-term load threshold defined for this component is reached, to inform the cyclist promptly of the need for service.

Claims

1. A method for detecting wear on at least one component of an electric bicycle, comprising:

monitoring an operating condition of the at least one component of the bicycle with the aid of at least one sensor;

detecting a stress on the component based on an operating time of the at least one component;

displaying on a display unit a need for service as soon as a long-term load threshold defined for the at least one component is reached, wherein the component is a drive train component, and wherein the stress relates to a mechanical wearing out of the drive train component, wherein the long-term load threshold represents a threshold that if met or exceeded indicates that the component requires servicing or replacement, wherein the drive train component is driven by an electric motor;

detecting a ripple component of a current of the electric motor;

comparing the detected ripple component to a ripple component of a reference signal; and

indicating that the mechanical wearing of the drive train component is present if a deviation between the detected ripple component and the ripple component of the reference signal exceeds a predefined value.

2. The method as recited in claim 1, wherein vibrations of at least one of a frame and a handlebar of the electric bicycle are detected with the aid of at least one acceleration sensor and displayed as soon as a predefined operational strength limit is reached.

3. The method as recited in claim 1, wherein a number of charging cycles of a battery of the electric bicycle is detected with the aid of at least one sensor and displayed as soon as a predefined number of charging cycles is reached.

4. The method as recited in claim 1, wherein an operating condition of a brake is monitored with the aid of at least one sensor by at least one of (i) detecting a speed characteristic of the vehicle and (ii) detecting the number of braking operations.

5. The method as recited in claim 1, wherein an operating condition of a chain of the electric bicycle is monitored with the aid of at least one sensor which detects the number of shift operations of the chain.

6. The method as recited in claim 1, wherein an operating condition of a chain of the electric bicycle is monitored with the aid of at least one sensor which detects an applied torque.

7. The method as recited in claim 1, wherein an operating condition of a chain of the electric bicycle is monitored with the aid of at least one sensor which detects a distance traveled by the electric bicycle.

8. The method as recited in claim 1, wherein an operating condition of a chain of the electric bicycle is monitored with the aid of at least one sensor which detects an engaged gear.

9. The method as recited in claim 1, wherein a sensor detects when a tire pressure is outside a predefined pressure range.

10. The method as recited in claim 1, wherein:

the drive train component is part of a chain drive of the electric bicycle and the electric motor drives at least one driveshaft having at least one sprocket wheel, at least one output shaft which is also equipped with at least one sprocket wheel, and at least one closed chain which is guided over the sprocket wheel of the driveshaft and the sprocket wheel of the output shaft such that the closed chain transmits a torque acting on the driveshaft to the output shaft;

the reference signal corresponds to a current signal which is detected when the chain drive is equipped with a new chain and new sprocket wheels.

11. The method as recited in claim 10, wherein an amplitude of the ripple component of the detected current signal of the motor current is compared with an amplitude of the ripple component of the reference signal.

12. The method as recited in claim 11, wherein a characteristic variable of the detected current signal is formed from a quotient of the maximum amplitude of the ripple component of the detected current signal and the motor frequency, and wherein the characteristic variable of the detected current signal is compared with a corresponding characteristic variable of the reference signal.

13. The method as recited in claim 12, wherein a wear condition is identified when the characteristic variable of the detected current signal is greater than a defined threshold value.

14. The method as recited in claim 10, wherein the deviation between the ripple component of the detected current signal of the motor current and the ripple component of the reference signal is ascertained only in a steady-state operation of the electric motor, wherein the steady-state operation is defined as when the average motor current is constant over a predefined minimum duration.

15. The method as recited in claim 14, wherein the deviation between the ripple component of the detected current signal of the motor current and the ripple component of the reference signal is ascertained automatically at predefined intervals.

16. The method as recited in claim 10, wherein a wear condition is displayed only when the average of the deviation between the ripple component of the detected current signal of the motor current and the ripple component of the reference signal exceeds a predefined value for a predefined period of time.

17. A device for detecting wear on at least one component of an electric bicycle, comprising:

at least one sensor configured to (i) monitor an operating condition of the at least one component of the bicycle with the aid of at least one sensor and (ii) detect a stress on the component based on an operating time of the at least one component;

an evaluation unit having at least one memory, wherein the evaluation unit is configured to evaluate a sensor signal from the at least one sensor; and

at least one display unit configured to display a need for service as soon as the evaluation unit determines a long-term load threshold defined for the at least one component has been reached, wherein the component is a drive train component, and wherein the stress relates to a mechanical wearing out of the drive train component, wherein the long-term load threshold represents a threshold that if met or exceeded indicates that the component requires servicing or replacement , wherein the drive train component is driven by an electric motor, and wherein the evaluation unit;

detects a ripple component of a current of the electric motor;

compares the detected ripple component to a ripple component of a reference signal, and

indicates that the mechanical wearing out of the drive train component is present if a deviation between the detected ripple component and the ripple component of the reference signal exceeds a predefined value.