Wireless, passive wheel-speed and cadence detection system

• US 20060049822A1
• Filed: 08/19/2005
• Published: 03/09/2006
• Est. Priority Date: 08/19/2004
• Status: Active Grant

• Current Assignee: Saris Cycling Group Incorporated
• Original Assignee: Saris Cycling Group Incorporated
• Inventors: Watson, Edward M.
• Granted Patent: US 7,408,447 B2
• Time in Patent Office: Days
• US Class Current: 324/174
• CPC Class Codes: B62J 43/30 for providing power to equipment other than for propulsion
• CPC Class Codes: B62J 45/412 Speed sensors
• CPC Class Codes: G01C 22/002 for cycles
• CPC Class Codes: G01P 1/08 Arrangements of scales, pointers, lamps or acoustic indicators, e.g. in automobile speedometers
• CPC Class Codes: G01P 3/487 delivered by rotating magnets

Abstract

A wireless, passive wheel-speed and detection system is provided for measuring the rate of rotation of a rotating component of a bicycle. The detection system includes a sensor arrangement having a first portion mounted on the bicycle and a second portion mounted on the rotating component. The sensor arrangement generates an input signal representative of a revolution of the rotating component. A transmitter circuit is operatively connected to the sensor arrangement for converting the input signal to a radio frequency signal and for transmitting the radio frequency signal. A controller receives the radio frequency signal and translates the radio frequency signal to a value indicative of a rate of rotation of the rotating component.

Claims

1. A detection system operable for measuring a cadence of an operator pedaling a bicycle, the bicycle having a frame supporting a pedal assembly, comprising:

a cadence circuit operatively connected to the bicycle for measuring the cadence of the operator pedaling the bicycle and generating a cadence signal corresponding to the measured cadence; and

a transmission circuit for generating a radio frequency signal corresponding to the cadence signal and transmitting the radio frequency signal to a target.

2. The detection system of claim 1 wherein the cadence circuit includes:

a sensing circuit mounted one of the frame and the pedal assembly;

an inducement element mounted to the other of the frame and pedal assembly, the inducement element causing the sensing circuit to generate an electrical signal in response to a revolution of the pedal assembly.

3. The detection system of claim 2 wherein the inducement element is a magnet.

4. The detection system of claim 2 wherein the sensing circuit includes:

a pickup coil generating an induced signal in response to the inducement element passing in proximity thereto; and

a transformer operatively connected to the pickup coil for transforming the induced signal and providing the induced signal to the transmission circuit as the cadence signal.

5. The detection circuit of claim 4 wherein the transformer has a primary coil electrically connected to the pickup coil and a secondary coil operatively connected to the transmission circuit.

6. The detection circuit of claim 5 wherein the transmission circuit includes:

an inductor; and

a capacitor circuit connected in parallel with the inductor.

7. The detection circuit of claim 1 wherein the target includes a controller connectable to the bicycle, the controller receiving the radio frequency signal transmitted by the transmission circuit and converting the radio frequency signaling to a cadence value for visual display.

8. The detection circuit of claim 2 wherein the sensing circuit includes:

a power source for generating electrical power; and

a reed switch operatively connecting the power source to the transmission circuit, the reed switch movable in response to the inducement element passing in proximity thereto between a open configuration and a closed configuration wherein the electrical power generated by the power source is provided to the transmission circuit as the cadence signal.

9. The detection circuit of claim 1 wherein the bicycle includes a fork assembly mounted to the frame and a wheel rotatably supported on the fork assembly, the detection circuit further comprising:

a second cadence circuit operatively connect to the fork assembly for generating a second cadence signal representative of a wheel speed of a wheel; and

a second transmission circuit for generating a second radio frequency signal corresponding to the second cadence signal and transmitting the second radio frequency signal to the target.

10. A detection system operable to measure the rate of rotation of a rotating component of a bicycle, the detection system comprising:

a sensor arrangement having a first portion mounted on the bicycle and a second portion mounted on the rotating component, the sensor arrangement operable to generate an input signal representative of a revolution of the rotating component;

a transmitter circuit operatively connected to the sensor arrangement for converting the input signal to a radio frequency signal and for transmitting the radio frequency signal; and

a controller for receiving the radio frequency signal and for translating the radio frequency signal to a value indicative of a rate of rotation of the rotating component.

11. The detection system of claim 10 wherein the controller includes a receiver configured to receive the radio frequency signal transmitted by the transmitter circuit.

12. The detection system of claim 10 wherein the first portion of the sensor arrangement includes a sensing circuit mounted to the bicycle and wherein the second portion of the sensor arrangement includes an inducement element mounted to the rotating component, the inducement element causing the sensor circuit to generate an electrical signal representative in response to a revolution of the pedal assembly.

13. The detection system of claim 12 wherein the sensing circuit includes:

a pickup coil generating the electrical signal in response to the inducement element passing in proximity thereto; and

a transformer operatively connected to the pickup coil for transforming the electrical 25 signal and providing the transformed electrical signal to the transmitter circuit as the cadence signal.

14. The detection circuit of claim 12 wherein the sensing circuit includes:

a power source for generating electrical power; and

a reed switch operatively connecting the power source to the transmission circuit, the reed switch movable in response to the inducement element passing in proximity thereto between a open configuration and a closed configuration wherein the electrical power generated by the power source is provided to the transmission circuit as the cadence signal.

15. The detection circuit of claim 10 wherein the bicycle includes a fork assembly mounted to the frame and a wheel rotatably supported on the fork assembly, the detection circuit further comprising:

a second cadence circuit operatively connect to the fork assembly for generating a second cadence signal representative of a wheel speed of a wheel; and

a second transmission circuit for generating a second radio frequency signal corresponding to the second cadence signal and transmitting the second radio frequency signal to the target.

16. A method of measuring a rate of rotation of a rotatable component of a bicycle, the bicycle including frame to which the component is rotatably mounted, the method comprising:

detecting a revolution of the rotatable component and generating an electrical signal in response thereto that is representative of the detected revolution of the rotatable component;

converting the electrical signal to a radio frequency signal; and

determining a rate of rotation of the component in response to the radio frequency signal.

17. The method of claim 16 comprising the additional step of wirelessly transmitting the radio frequency signal prior to the step of determining the rate of rotation.

18. The method of claim 16 wherein the rotatable component is a pedal assembly of the bicycle.

19. The method of claim 16 wherein the rotatable component is a wheel rotatably supported by the frame of the bicycle.

20. The method of claim 16 further comprising the additional steps of:

providing a power source for generating the electrical signal;

selectively closing a predetermined switch in response to the revolution of the rotatable component; and

converting the electrical signal in response to closure of the predetermined switch.