Measuring force transmitted by force transmission equipment

• US 6,684,713 B2
• Filed: 08/17/2001
• Issued: 02/03/2004
• Est. Priority Date: 08/25/2000
• Status: Expired due to Term

• Current Assignee: Polar Electro Oy
• Original Assignee: Polar Electro Oy
• Inventors: Nissilä, Seppo
• Primary Examiner(s): Williams, Hezron
• Assistant Examiner(s): HANLEY, JOHN C
• Application Number:
  US09/932,470
• Publication Number:
  US 20020023494A1
• Time in Patent Office: 900 Days
• Field of Search: 735/81, 738/624.1, 738/624.73, 738/625.9, 738/626.26, 737/80, 737/81, 737/69, 738/28, 737/75, 737/79
• US Class Current: 73/775
• CPC Class Codes: B62J 45/20 Cycle computers as cycle accessories
• CPC Class Codes: B62J 50/22 electronic, e.g. displays
• CPC Class Codes: G01L 5/042 by measuring vibrational characteristics of the flexible member

Abstract

A bicycle which comprises as force transmission equipment a chain for transmitting the muscular strength of a person pedaling the bicycle from the person to the bicycle for the purpose of moving the bicycle, characterized in that the chain has a vibration transducer which is arranged to vibrate at a resonance frequency proportional to the force transmitted by the chain, and the bicycle comprises a reading device separate from the chain for reading the resonance frequency of the vibration transducer, to which reading device calculation means are connected for calculating the force affecting the chain on the basis of the resonance frequency.

Claims

1. A vibration transducer for use in measuring the tensile stress transmitted by force transmission equipment, wherein the vibration transducer intended to be fastened to the force transmission equipment is arranged to receive an electromagnetic excitation and to vibrate at a resonance frequency proportional to the tensile stress affecting the force transmission equipment, the resonance frequency being wirelessly readable for use in calculating the tensile stress transmitted by the force transmission equipment, the force transmission equipment being a bicycle chain, the chain comprising chain pieces which are connected to each other by axle pins, the vibration transducer being at least one of located in an axle pin and fastened to a side plate of a chain piece, the vibration transducer vibrating at a resonance frequency proportional to the tensile stress transmitted by the chain.

2. A vibration transducer as claimed in claim 1, wherein the vibration transducer is a coil capacitor circuit.

3. A method for measuring the force transmitted by force transmission equipment, in which method the force transmission equipment is arranged to be a closed loop so that it is connected to a first turning means and from the first turning means to a separate second turning means, and the turning of the first turning means by a power source causes force to transmit by means of the force transmission equipment to the second turning means, turning the second turning means in the same direction as the first turning means, comprising the steps of reading with a reading device separate from the force transmission equipment the resonance frequency of a vibration transducer in the force transmission equipment, the resonance frequency being dependent on the level of the force transmitted by the force transmission equipment, and calculating with calculation means connected to the reading device on the basis of the resonance frequency the force transmitted by the force transmission equipment, an electromagnetic excitation being transmitted from the reading device to make the vibration transducer vibrate at a resonance frequency proportional to the force transmitted by the force transmission equipment and the resonance frequency of the vibration transducer being read wirelessly by the reading device for the purpose of using it in calculating the force transmitted by the force transmission equipment, the force transmission equipment being a bicycle chain, the chain comprising chain pieces which are connected to each other in a closed loop by axle pins, the vibration transducer being located in at least one of an axle pin and a side plate of a chain piece of the chain.

4. A method as claimed in claim 3, wherein the vibration transducer is a coil capacitor circuit.

5. A method as claimed in claim 3, wherein a velocity of the vibration transducer is measured in relation to the reading device.

6. A method as claimed in claim 5, wherein the power transmitted by the force transmission equipment is established by means of the velocity and the force transmitted by the force transmission equipment.

7. A method as claimed in claim 3, wherein the force transmitted by a bicycle chain is measured and the reading device is located on a bicycle so that the vibration transducer fastened to the bicycle chain runs past or through the reading device so as to make the resonance frequency of the vibration transducer readable by the reading device.

8. An arrangement for measuring the force transmitted by force transmission equipment, comprising force transmission equipment in a closed loop and a first turning means connected to the force transmission equipment and a second turning means separate from the first turning means and connected to the force transmission equipment, the turning of the first turning means by a power source causing force to transmit by means of the force transmission equipment to the second turning means, turning the second turning means in the same direction as the first turning means, a vibration transducer for establishing a resonance frequency proportional to the force transmitted by the force transmission equipment, and the arrangement comprises a reading device structurally separate from the force transmission equipment for reading the resonance frequency of the vibration transducer, and the arrangement further comprises calculation means connected to the reading device for calculating the force transmitted by the force transmission equipment on the basis of the resonance frequency of the vibration transducer, the reading device in the arrangement being arranged to generate an electromagnetic excitation to make the vibration transducer vibrate at a resonance frequency, the reading device being further arranged to wirelessly receive an electromagnetic response corresponding to the resonance frequency of the vibration transducer, the force transmission equipment being a bicycle chain, the chain comprising chain pieces, extension pieces of the chain being connected by axle pins of the chain, the vibration transducer being located in at least one of an axle pin and a side plate of a chain piece of the chain.

9. An arrangement as claimed in claim 8, wherein the reading device is arranged to measure a velocity of the vibration transducer in relation to the reading device.

10. An arrangement as claimed in claim 9, wherein a calculation unit is arranged to calculate the power transmitted by the force transmission equipment by means of the velocity of the vibration transducer and the force transmitted by the force transmission equipment.

11. An arrangement as claimed in claim 8, wherein the reading device is located on a bicycle being subjected to force measurement so that the vibration transducer fastened to a chain of the bicycle can be read by the reading device when the vibration transducer passes by or through the reading device.

12. An arrangement as claimed in claim 8, wherein the vibration transducer is a coil capacitor circuit.

13. A bicycle which comprises as force transmission equipment a chain for transmitting the muscular strength of a person pedaling the bicycle from the person to the bicycle for the purpose of moving the bicycle, wherein the chain has a vibration transducer which is arranged to vibrate at a resonance frequency proportional to the force transmitted by the chain, and the bicycle comprises a reading device separate from the chain for reading the resonance frequency of the vibration transducer, to which reading device calculation means are connected for calculating the force affecting the chain on the basis of the resonance frequency, the reading device being arranged to generate an electromagnetic excitation to make the vibration transducer vibrate at a resonance frequency proportional to the force transmitted by the force transmission equipment, the reading device being further arranged to wirelessly read the resonance frequency of the vibration transducer, the chain comprising chain pieces which are connected to each other by axle pins, the vibration transducer being located in at least one of an axle pin and a side plate of a chain piece.

14. A bicycle as claimed in claim 13, wherein the vibration transducer is a coil capacitor circuit.

15. A bicycle as claimed in claim 13, wherein the reading device is arranged to measure the velocity of the vibration transducer in relation to the reading device.

16. A bicycle as claimed in claim 15, wherein a calculation unit is arranged to establish the power transmitted by the chain by means of the velocity and the force transmitted by the chain.

17. A bicycle as claimed in claim 13, wherein the reading device is located on the bicycle so that the vibration transducer fastened to the chain can be read by the reading device when the vibration transducer passes by or through the reading device.