Inductive energy transfer system

• US 6,571,933 B1
• Filed: 11/15/2001
• Issued: 06/03/2003
• Est. Priority Date: 10/20/1998
• Status: Expired due to Term

• Current Assignee: Crisplant a/s (BEUMER Group GmbH & Co. KG)
• Original Assignee: Crisplant a/s (BEUMER Group GmbH & Co. KG)
• Inventors: Lykkegaard, Uffe, Glud, Knud Erik, Kloster, Aksel, Simonsen, Henrik Duch, Gortz, Ole, Larsen, Benny
• Primary Examiner(s): Bidwell, James R.
• Application Number:
  US09/807,936
• Time in Patent Office: 565 Days
• Field of Search: 198/370.06, 198/619
• US Class Current: 198/619
• CPC Class Codes: B65G 17/345 the surfaces being equipped with a conveyor
• CPC Class Codes: B65G 2201/02 Articles
• CPC Class Codes: B65G 2207/18 Crossing conveyors
• CPC Class Codes: B65G 23/00 Driving gear for endless conveyors; Belt- or chain-tensioning arrangements

Abstract

An inductive energy transfer system supplies energy from a stationary primary rail to a number of movable secondary rails each connected to a movable unit. The system is particularly suited for conveyor units of a sorter system, each unit having an article support, the energy provided from the energy transfer system being used primarily for discharging articles from the article-support. The primary rail as well as the secondary rails are provided with legs so that the legs in an operational position are overlapping so as to reduce the losses caused by the air gap between the primary rail and the secondary rails. The movable units are each equipped with an electrical battery for smoothing the load from the movable unit on the primary side of the transfer system.

Claims

1. A sorter for conveying and sorting articles comprising:

a guide rail forming a closed loop,

a U-shaped primary rail made from a magnetic conducting material and having a primary coil connected to a power supply unit for generating an actuating current in the primary coil, the primary rail being positioned along at least a part of the guide rail, and

a plurality of movable units moving along said guide rail, each unit having article-supporting means defining at least one article-supporting surface, means for discharging articles from said surface and a U-shaped secondary rail made from a magnetic conducting material and having a secondary coil, the secondary rail being so positioned during operation that, over a substantial part of the secondary rail in the direction of motion of the unit, the legs of the primary rail and the legs of the secondary rail overlap perpendicularly to the direction of motion, the overlap being of at least twice the distance between the leg in question of the primary rail and the corresponding leg of the secondary rail, the unit having means for using energy inducted in the secondary coil for driving the means for discharging articles.

2. The sorter according to claim 1, wherein the movable units comprise energy storage means for storing energy inducted in the secondary coil.

3. The sorter according to claim 2, wherein the storage means comprises a battery.

4. The sorter according to claim 1, comprising a shield made from a non-ferromagnetic, electrically conducting material, the shield substantially encircles the outer of the primary rail at a distance less than the distance between the leg of the primary rail and the corresponding leg of the secondary rail.

5. The sorter according to claim 4, wherein the shield mainly is made from aluminium.

6. The sorter according to claim 1, wherein the secondary rail is provided with a middle leg carrying the secondary coil, the primary coil being arranged so that a first part of at least one winding of the primary coil passes between a first leg of the secondary rail and the middle leg and a second part of the at least one winding carrying the return current of the first part passes between a second leg of the secondary rail and the middle leg.

7. The sorter according to claim 1, wherein the primary coil is arranged within the primary rail and is carried by holding means made from a non-ferromagnetic material.

8. The sorter according to claim 1, wherein the article-supporting means of the movable units comprises an endless belt defining the article-supporting surface, the belt being movably arranged and having means for moving the belt so as to discharge articles carried by the belt.

9. The sorter according to claim 8, wherein the belt is movably arranged in a direction substantially perpendicular to the direction of motion of the unit.

10. The sorter according to claim 1, wherein the power supply unit comprises means for impressing a pulsed actuating voltage onto the primary coil which forms part of a tuned resonance circuit comprising a capacitor and the power supply unit further comprises means for measuring the magnitude of the generated current in the primary coil and adjusting the pulse-width of the actuating voltage in order to achieve a predetermined magnitude of the generated current.

11. The sorter according to claim 1, wherein the power supply unit comprises means for impressing a pulsed actuating voltage onto the primary coil which forms part of a tuned resonance circuit comprising a capacitor and the power supply unit further comprises means for successively changing the frequency of the actuating voltage within a predetermined frequency range and means for determining the temporal relation between the pulses of the actuating voltage and the phase of the generated current so as to determine the resonance frequency of the tuned resonance circuit.

12. A system for inductive energy transfer comprising:

a U-shaped primary rail made from a magnetic conducting material and having a primary coil connected to a power supply unit for generating an actuating current in the primary coil, and

a plurality of movable units each having a U-shaped secondary rail made from a magnetic conducting material and having a secondary coil, the secondary rail being so positioned during operation that, over a substantial part of the secondary rail in the direction of motion of the unit, the legs of the primary rail and the legs of the secondary rail overlap perpendicularly to the direction of motion, the overlap being of at least twice the distance between the leg in question of the primary rail and the corresponding leg of the secondary rail.

13. The system according to claim 12, wherein the movable units comprise energy storage means for storing energy inducted in the secondary coil.

14. The system according to claim 13, wherein the storage means comprises a battery.

15. The system according to claim 12, comprising a shield made from a non-ferromagnetic, electrically conducting material, the shield substantially encircles the outer of the primary rail at a distance less than the distance between the leg of the primary rail and the corresponding leg of the secondary rail.

16. The system according to claim 15, wherein the shield mainly is made from aluminium.

17. The system according to claim 12, wherein the secondary rail is provided with a middle leg carrying the secondary coil, the primary coil being arranged so that a first part of at least one winding of the primary coil passes between a first leg of the secondary rail and the middle leg and a second part of the at least one winding carrying the return current of the first part passes between a second leg of the secondary rail and the middle leg.

18. The system according to claim 12, wherein the primary coil is arranged within the primary rail and is carried by holding means made from a non-ferromagnetic material.

19. The system according to claim 12, wherein the power supply unit comprises means for impressing a pulsed actuating voltage onto the primary coil which forms part of a tuned resonance circuit comprising a capacitor and the power supply unit further comprises means for measuring the magnitude of the generated current in the primary coil and adjusting the pulse-width of the actuating voltage in order to achieve a predetermined magnitude of the generated current.

20. The system according to claim 12, wherein the power supply unit comprises means for impressing a pulsed actuating voltage onto the primary coil which forms part of a tuned resonance circuit comprising a capacitor and the power supply unit further comprises means for successively changing the frequency of the actuating voltage within a predetermined frequency range and means for determining the temporal relation between the pulses of the actuating voltage and the phase of the generated current so as to determine the resonance frequency of the tuned resonance circuit.

21. A system for inductive energy transfer comprising:

a primary coil connected to a power supply unit for generating an actuating current in the primary coil, and

a plurality of movable units each having a secondary coil,

wherein the power supply unit comprises means for impressing a pulsed actuating voltage onto the primary coil which forms part of a tuned resonance circuit comprising a capacitor and the power supply unit further comprises means for measuring the magnitude of the generated current in the primary coil and adjusting the pulse-width of the actuating voltage in order to achieve a predetermined magnitude of the generated current.

22. The system according to claim 21, wherein the power supply unit further comprises means for successively changing the frequency of the actuating voltage within a predetermined frequency range and means for determining the temporal relation between the pulses of the actuating voltage and the phase of the generated current so as to determine the resonance frequency of the tuned resonance circuit.

23. The system according to claim 21, wherein the movable units comprise energy storage means for storing energy inducted in the secondary coil.

24. The system according to claim 23, wherein the storage means comprises a battery.